Combined Aircraft and Satellite-Derived Storm Electric Current and Lightning Rates Measurements and Implications for the Global Electric Circuit

NASA Technical Reports Server (NTRS)

Mach, Douglas M.; Blakeslee, Richard J.; Bateman, Monte G.

2010-01-01

Using rotating vane electric field mills and Gerdien capacitors, we measured the electric field profile and conductivity during 850 overflights of electrified shower clouds and thunderstorms spanning regions including the Southeastern United States, the Western Atlantic Ocean, the Gulf of Mexico, Central America and adjacent oceans, Central Brazil, and the South Pacific. The overflights include storms over land and ocean, with and without lightning, and with positive and negative fields above the storms. The measurements were made with the NASA ER-2 and the Altus-II high altitude aircrafts. Peak electric fields, with lightning transients removed, ranged from -1.0 kV/m to 16 kV/m, with a mean value of 0.9 kV/m. The median peak field was 0.29 kV/m. Integrating our electric field and conductivity data, we determined total conduction currents and flash rates for each overpass. With knowledge of the storm location (land or ocean) and type (with or without lightning), we determine the mean currents by location and type. The mean current for ocean storms with lightning is 1.6 A while the mean current for land storms with lightning is 1.0 A. The mean current for oceanic storms without lightning (i.e., electrified shower clouds) is 0.39 A and the mean current for land storms without lightning is 0.13 A. Thus, on average, land storms with or without lightning have about half the mean current as their corresponding oceanic storm counterparts. Over three-quarters (78%) of the land storms had detectable lightning, while less than half (43%) of the oceanic storms had lightning. We did not find any significant regional or latitudinal based patterns in our total conduction currents. By combining the aircraft derived storm currents and flash rates with diurnal lightning statistics derived from the Lightning Imaging Sensor (LIS) and Optical Transient Detector (OTD) low Earth orbiting satellites, we reproduce the diurnal variation in the global electric circuit (i.e., the Carnegie curve) to within 4% for all but two short periods of time. This excellent agreement with the Carnegie curve was obtained without any tuning or adjustment of the satellite or aircraft data. Given our data and assumptions, mean contributions to the global electric circuit are 0.7 kA (ocean) and 1.1 kA (land) from lightning-producing storms, and 0.22 kA (ocean) and 0.04 (land) from electrified shower clouds, resulting in a mean total conduction current estimate for the global electric circuit of 2.0 kA. Breaking the results down into mean storm counts reveals 1100 for land storms with lightning, 530 for ocean storms without lightning, 390 for ocean storms with lightning, and 330 for land storms without lightning.

Distribution of E/N and N/e/ in a cross-flow electric discharge laser. [electric field to neutral gas density and electron number density

NASA Technical Reports Server (NTRS)

Dunning, J. W., Jr.; Lancashire, R. B.; Manista, E. J.

1976-01-01

Measurements have been conducted of the effect of the convection of ions and electrons on the discharge characteristics in a large scale laser. The results are presented for one particular distribution of ballast resistance. Values of electric field, current density, input power density, ratio of electric field to neutral gas density (E/N), and electron number density were calculated on the basis of measurements of the discharge properties. In a number of graphs, the E/N ratio, current density, power density, and electron density are plotted as a function of row number (downstream position) with total discharge current and gas velocity as parameters. From the dependence of the current distribution on the total current, it appears that the electron production in the first two rows significantly affects the current flowing in the succeeding rows.

Medical Simulation Practices 2010 Survey Results

NASA Technical Reports Server (NTRS)

McCrindle, Jeffrey J.

2011-01-01

Medical Simulation Centers are an essential component of our learning infrastructure to prepare doctors and nurses for their careers. Unlike the military and aerospace simulation industry, very little has been published regarding the best practices currently in use within medical simulation centers. This survey attempts to provide insight into the current simulation practices at medical schools, hospitals, university nursing programs and community college nursing programs. Students within the MBA program at Saint Joseph's University conducted a survey of medical simulation practices during the summer 2010 semester. A total of 115 institutions responded to the survey. The survey resus discuss overall effectiveness of current simulation centers as well as the tools and techniques used to conduct the simulation activity

Sodium and potassium conductance changes during a membrane action potential.

PubMed

Bezanilla, F; Rojas, E; Taylor, R E

1970-12-01

1. A method for turning a membrane potential control system on and off in less than 10 musec is described. This method was used to record membrane currents in perfused giant axons from Dosidicus gigas and Loligo forbesi after turning on the voltage clamp system at various times during the course of a membrane action potential.2. The membrane current measured just after the capacity charging transient was found to have an almost linear relation to the controlled membrane potential.3. The total membrane conductance taken from these current-voltage curves was found to have a time course during the action potential similar to that found by Cole & Curtis (1939).4. The instantaneous current voltage curves were linear enough to make it possible to obtain a good estimate of the individual sodium and potassium channel conductances, either algebraically or by clamping to the sodium, or potassium, reversal potentials. Good general agreement was obtained with the predictions of the Hodgkin-Huxley equations.5. We consider these results to constitute the first direct experimental demonstration of the conductance changes to sodium and potassium during the course of an action potential.

Temperature-dependent analysis of conduction mechanism of leakage current in thermally grown oxide on 4H-SiC

NASA Astrophysics Data System (ADS)

Sometani, Mitsuru; Okamoto, Dai; Harada, Shinsuke; Ishimori, Hitoshi; Takasu, Shinji; Hatakeyama, Tetsuo; Takei, Manabu; Yonezawa, Yoshiyuki; Fukuda, Kenji; Okumura, Hajime

2015-01-01

The conduction mechanism of the leakage current of a thermally grown oxide on 4H silicon carbide (4H-SiC) was investigated. The dominant carriers of the leakage current were found to be electrons by the carrier-separation current-voltage method. The current-voltage and capacitance-voltage characteristics, which were measured over a wide temperature range, revealed that the leakage current in SiO2/4H-SiC on the Si-face can be explained as the sum of the Fowler-Nordheim (FN) tunneling and Poole-Frenkel (PF) emission leakage currents. A rigorous FN analysis provided the true barrier height for the SiO2/4H-SiC interface. On the basis of Arrhenius plots of the PF current separated from the total leakage current, the existence of carbon-related defects and/or oxygen vacancy defects was suggested in thermally grown SiO2 films on the Si-face of 4H-SiC.

Temperature-dependent analysis of conduction mechanism of leakage current in thermally grown oxide on 4H-SiC

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

Sometani, Mitsuru; Takei, Manabu; Fuji Electric Co. Ltd., 1 Fuji-machi, Hino, 191-8502 Tokyo

The conduction mechanism of the leakage current of a thermally grown oxide on 4H silicon carbide (4H-SiC) was investigated. The dominant carriers of the leakage current were found to be electrons by the carrier-separation current-voltage method. The current-voltage and capacitance-voltage characteristics, which were measured over a wide temperature range, revealed that the leakage current in SiO{sub 2}/4H-SiC on the Si-face can be explained as the sum of the Fowler-Nordheim (FN) tunneling and Poole-Frenkel (PF) emission leakage currents. A rigorous FN analysis provided the true barrier height for the SiO{sub 2}/4H-SiC interface. On the basis of Arrhenius plots of the PFmore » current separated from the total leakage current, the existence of carbon-related defects and/or oxygen vacancy defects was suggested in thermally grown SiO{sub 2} films on the Si-face of 4H-SiC.« less

Global Electric Circuit Implications of Total Current Measurements over Electrified Clouds

NASA Technical Reports Server (NTRS)

Mach, Douglas M.; Blakeslee, Richard J.; Bateman, Monte G.

2009-01-01

We determined total conduction (Wilson) currents and flash rates for 850 overflights of electrified clouds spanning regions including the Southeastern United States, the Western Atlantic Ocean, the Gulf of Mexico, Central America and adjacent oceans, Central Brazil, and the South Pacific. The overflights include storms over land and ocean, with and without lightning, and with positive and negative Wilson currents. We combined these individual storm overflight statistics with global diurnal lightning variation data from the Lightning Imaging Sensor (LIS) and Optical Transient Detector (OTD) to estimate the thunderstorm and electrified shower cloud contributions to the diurnal variation in the global electric circuit. The contributions to the global electric circuit from lightning producing clouds are estimated by taking the mean current per flash derived from the overflight data for land and ocean overflights and combining it with the global lightning rates (for land and ocean) and their diurnal variation derived from the LIS/OTD data. We estimate the contribution of non-lightning producing electrified clouds by assuming several different diurnal variations and total non-electrified storm counts to produce estimates of the total storm currents (lightning and non-lightning producing storms). The storm counts and diurnal variations are constrained so that the resultant total current diurnal variation equals the diurnal variation in the fair weather electric field (+/-15%). These assumptions, combined with the airborne and satellite data, suggest that the total mean current in the global electric circuit ranges from 2.0 to 2.7 kA, which is greater than estimates made by others using other methods.

The tobacco endgame in Hong Kong: public support for a total ban on tobacco sales.

PubMed

Wang, Man Ping; Wang, Xin; Lam, Tai Hing; Viswanath, Kasisomayajula; Chan, Sophia S

2015-03-01

Tobacco endgame policies are increasingly advocated to end tobacco use. This study investigated public support for a total ban on tobacco sales, use and possession in Hong Kong. A telephone survey was conducted among 1537 randomly selected residents in 2012 to assess their support for a total ban on tobacco sales, usage and possession. Information on sociodemographic characteristics, smoking, and second hand smoke exposure were collected. Logistic regression was used to investigate factors associated with support for a total ban. Most of the never smokers (75.3%), ex-smokers (63.9%), and nearly half of current smokers (48.9%) backed some form of a total ban on tobacco. A total ban on tobacco sales was the most popular option among the three groups, with over half (64.8%) of all respondents supporting a ban within 10 years. Current smoking and higher educational attainment were associated with less support for a total ban on tobacco sales. Among current smokers, having quit intentions and attempts to quit were associated with support for a total ban. A total ban on tobacco sales was supported by most respondents. Ex-smokers and current smokers also voiced substantial support, although less than never smokers. A total ban on tobacco sales before 2022 should be the goal as it is supported by most of the respondents. Interim tobacco control measures, such as tax increases, expansion of smoking cessation services and plain packaging should be implemented to help current smokers quit and reduce smoking initiation before implementation of the ban. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Current status of registry of vaccine clinical trials conducted by Korean investigators in ClinicalTrials.gov, database of US National Institutes of Health.

PubMed

Cho, Jahyang; Kim, Bo Bae; Bae, Chong-Woo; Cha, Sung-Ho

2013-01-01

PubMed is not only includes international medical journals but also has a registration site for the ongoing clinical trials, such as ClinicalTrials.gov, under the supervision of US National Institutes of Health. We analyzed current status of vaccine clinical trials conducted by Korean investigators in database of ClinicalTrial.gov. As of October 2012, there are total of 72 trials found on registry of vaccine clinical trials conducted by Korean investigators in database of ClinicalTrial.gov. These trials were analyzed and classified by conditions of vaccine clinical trials, biologicals or drugs used in vaccine clinical trials, status of proceeding research, and list of sponsor and collaborators. Total 72 trials of vaccine clinical trials conducted by Korean investigators are classified by groups of infection (64 trials), cancer (4 trials), and others (4 trials). Infections group shown are as follows: poliomyelitis, pertussis, diphtheria, tetanus, and Haemophilus influenzae type b (10), influenza (9), human papillomavirus infection (8), pneumococcal vaccine (6), herpes zoster (4), smallpox (4), hepatitis B (4), etc. One trial of each in lung cancer, breast cancer, prostate cancer, and colorectal cancer are shown in cancer group. One trial of each in Crohn's disease, ulcerative colitis, renal failure, and rheumatoid arthritis are shown in other group. Vaccine clinical trials conducted by Korean investigators in ClinicalTrial.gov reflects the current status of Korean research on vaccine clinical trials at the international level and can indicate research progress. It is hoped that this aids the development of future vaccine clinical trials in Korea.

Charging in the ac Conductance of a Double Barrier Resonant Tunneling Structure

NASA Technical Reports Server (NTRS)

Anantram, M. P.; Saini, Subhash (Technical Monitor)

1998-01-01

There have been many studies of the linear response ac conductance of a double barrier resonant tunneling structure (DBRTS), both at zero and finite dc biases. While these studies are important, they fail to self consistently include the effect of the time dependent charge density in the well. In this paper, we calculate the ac conductance at both zero and finite do biases by including the effect of the time dependent charge density in the well in a self consistent manner. The charge density in the well contributes to both the flow of displacement currents in the contacts and the time dependent potential in the well. We find that including these effects can make a significant difference to the ac conductance and the total ac current is not equal to the simple average of the non-selfconsistently calculated conduction currents in the two contacts. This is illustrated by comparing the results obtained with and without the effect of the time dependent charge density included correctly. Some possible experimental scenarios to observe these effects are suggested.

Conducting processes in simulated chronic inflammatory demyelinating polyneuropathy at 20°C-42°C.

PubMed

Stephanova, D I; Daskalova, M; Mladenov, M

2015-03-01

Decreased conducting processes leading usually to conduction block and increased weakness of limbs during cold (cold paresis) or warmth (heat paresis) have been reported in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). To explore the mechanisms of these symptoms, the effects of temperature (from 20°C to 42°C) on nodal action potentials and their current kinetics in previously simulated case of 70% CIDP are investigated, using our temperature dependent multi-layered model of the myelinated human motor nerve fiber. The results show that potential amplitudes have a bifid form at 20°C. As in the normal case, for the CIDP case, the nodal action potentials are determined mainly by the nodal sodium currents (I Na ) for the temperature range of 20-39°C, as the contribution of nodal fast and slow potassium currents (I Kf and I Ks ) to the total ionic current (Ii) is negligible. Also, the contribution of I Kf and I Ks to the membrane repolarization is enhanced at temperatures higher than 39°C. However, in the temperature range of 20-42°C, all potential parameters in the CIDP case, except for the conduction block during hyperthermia (≥ 40°C) which is again at 45°C, worsen: (i) conduction velocities and potential amplitudes are decreased; (ii) afterpotentials and threshold stimulus currents for the potential generation are increased; (iii) the current kinetics of action potentials is slowed and (iv) the conduction block during hypothermia (≤ 25°C) is at temperatures lower than 20°C. These potential parameters are more altered during hyperthermia and are most altered during hypothermia. The present results suggest that the conducting processes in patients with CIDP are in higher risk during hypothermia than hyperthermia.

NATIONAL ENVIRONMENTAL/ENERGY WORKFORCE ASSESSMENT. RADIATION PROGRAMS

EPA Science Inventory

The report describes radiation education/training programs which are currently being conducted in 23 states and one territory. In total there are 39 program entries included in this volume. Although the report attempts to concentrate mainly on radiation protection programs, aspec...

Microscopic origin of read current noise in TaOx-based resistive switching memory by ultra-low temperature measurement

NASA Astrophysics Data System (ADS)

Pan, Yue; Cai, Yimao; Liu, Yefan; Fang, Yichen; Yu, Muxi; Tan, Shenghu; Huang, Ru

2016-04-01

TaOx-based resistive random access memory (RRAM) attracts considerable attention for the development of next generation nonvolatile memories. However, read current noise in RRAM is one of the critical concerns for storage application, and its microscopic origin is still under debate. In this work, the read current noise in TaOx-based RRAM was studied thoroughly. Based on a noise power spectral density analysis at room temperature and at ultra-low temperature of 25 K, discrete random telegraph noise (RTN) and continuous average current fluctuation (ACF) are identified and decoupled from the total read current noise in TaOx RRAM devices. A statistical comparison of noise amplitude further reveals that ACF depends strongly on the temperature, whereas RTN is independent of the temperature. Measurement results combined with conduction mechanism analysis show that RTN in TaOx RRAM devices arises from electron trapping/detrapping process in the hopping conduction, and ACF is originated from the thermal activation of conduction centers that form the percolation network. At last, a unified model in the framework of hopping conduction is proposed to explain the underlying mechanism of both RTN and ACF noise, which can provide meaningful guidelines for designing noise-immune RRAM devices.

40 CFR 142.14 - Records kept by States.

Code of Federal Regulations, 2010 CFR

2010-07-01

... alternative filtration technology, in combination with disinfection treatment, consistently achieves 99.9... of viruses, may use such alternative filtration technology, shall be kept until the decision is... history of total coliform contamination in its current configuration and had a sanitary survey conducted...

Current distribution in tissues with conducted electrical weapons operated in drive-stun mode.

PubMed

Panescu, Dorin; Kroll, Mark W; Brave, Michael

2016-08-01

The TASER® conducted electrical weapon (CEW) is best known for delivering electrical pulses that can temporarily incapacitate subjects by overriding normal motor control. The alternative drive-stun mode is less understood and the goal of this paper is to analyze the distribution of currents in tissues when the CEW is operated in this mode. Finite element modeling (FEM) was used to approximate current density in tissues with boundary electrical sources placed 40 mm apart. This separation was equivalent to the distance between drive-stun mode TASER X26™, X26P, X2 CEW electrodes located on the device itself and between those located on the expended CEW cartridge. The FEMs estimated the amount of current flowing through various body tissues located underneath the electrodes. The FEM simulated the attenuating effects of both a thin and of a normal layer of fat. The resulting current density distributions were used to compute the residual amount of current flowing through deeper layers of tissue. Numerical modeling estimated that the skin, fat and skeletal muscle layers passed at least 86% or 91% of total CEW current, assuming a thin or normal fat layer thickness, respectively. The current density and electric field strength only exceeded thresholds which have increased probability for ventricular fibrillation (VFTJ), or for cardiac capture (CCTE), in the skin and the subdermal fat layers. The fat layer provided significant attenuation of drive-stun CEW currents. Beyond the skeletal muscle layer, only fractional amounts of the total CEW current were estimated to flow. The regions presenting risk for VF induction or for cardiac capture were well away from the typical heart depth.

Patriot Advanced Capability-3 Missile Segment Enhancement (PAC-3 MSE)

DTIC Science & Technology

2015-12-01

Threshold Demonstrated Performance Current Estimate System Training Proficiency Level Soldiers (Operators, Maintainers, and Leaders) are able to...constructive training environments by using TADSS to conduct multi- level training for both operators and maintenance personnel. With the addition...0.0 Total 6037.0 6037.0 N/A 6276.9 6722.3 6722.3 6900.3 Current APB Cost Estimate Reference Army Cost Position dated February 28, 2014 Confidence Level

Passive fault current limiting device

DOEpatents

Evans, Daniel J.; Cha, Yung S.

1999-01-01

A passive current limiting device and isolator is particularly adapted for use at high power levels for limiting excessive currents in a circuit in a fault condition such as an electrical short. The current limiting device comprises a magnetic core wound with two magnetically opposed, parallel connected coils of copper, a high temperature superconductor or other electrically conducting material, and a fault element connected in series with one of the coils. Under normal operating conditions, the magnetic flux density produced by the two coils cancel each other. Under a fault condition, the fault element is triggered to cause an imbalance in the magnetic flux density between the two coils which results in an increase in the impedance in the coils. While the fault element may be a separate current limiter, switch, fuse, bimetal strip or the like, it preferably is a superconductor current limiter conducting one-half of the current load compared to the same limiter wired to carry the total current of the circuit. The major voltage during a fault condition is in the coils wound on the common core in a preferred embodiment.

Passive fault current limiting device

DOEpatents

Evans, D.J.; Cha, Y.S.

1999-04-06

A passive current limiting device and isolator is particularly adapted for use at high power levels for limiting excessive currents in a circuit in a fault condition such as an electrical short. The current limiting device comprises a magnetic core wound with two magnetically opposed, parallel connected coils of copper, a high temperature superconductor or other electrically conducting material, and a fault element connected in series with one of the coils. Under normal operating conditions, the magnetic flux density produced by the two coils cancel each other. Under a fault condition, the fault element is triggered to cause an imbalance in the magnetic flux density between the two coils which results in an increase in the impedance in the coils. While the fault element may be a separate current limiter, switch, fuse, bimetal strip or the like, it preferably is a superconductor current limiter conducting one-half of the current load compared to the same limiter wired to carry the total current of the circuit. The major voltage during a fault condition is in the coils wound on the common core in a preferred embodiment. 6 figs.

Additional Sediment/Soil Sampling Conducted at the Little Sioux Bend Shallow Water Habitat Project Site during October 2013

DTIC Science & Technology

2013-11-01

Conditions in the Missouri River and Gulf of Mexico ................................................43 4.3 Comparison of Total Phosphorus Levels...Sediment Management” which assessed nutrient loadings to the Missouri River and Gulf of Mexico (NRC, 2011). The report concluded that potential...concern regarding Gulf of Mexico hypoxia. Currently, the total phosphorus load to the Gulf of Mexico is estimated to be 154,300 metric tons per year

Porous CoO nanostructures grown on three-dimension graphene foams for supercapacitors electrodes

NASA Astrophysics Data System (ADS)

Deng, Wei; Lan, Wei; Sun, Yaru; Su, Qing; Xie, Erqing

2014-06-01

Three-dimensional graphene foams with good conductivity, light weight and chemical stability were produced by chemical vapor deposition. Then porous CoO nanowalls were deposited on graphene foam by a simple hydrothermal process and subsequent thermal treatment. This hybrid structures possessing large surface area in which the CoO nanowalls are separated by graphene foam with robust adhesion can directly serve as supercapacitor electrode including current collector without the need of any other binder materials and conductive agents. Electrochemical tests manifest a high specific capacitance of 231.87 F/g scaled to the mass of CoO (139.47 F/g for total mass of electrodes) at 1 A/g current, good rate capability and excellent cycling performance of >98% capacitance retention over 1000 cycles at 7 A/g current. The high conductivity, light weight and rational architectures, which provide fast electron pathway and the low diffusion resistance of ions, are responsible for the high performance of the electrodes.

Microscopic origin of read current noise in TaO{sub x}-based resistive switching memory by ultra-low temperature measurement

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

Pan, Yue; Cai, Yimao, E-mail: caiyimao@pku.edu.cn; Liu, Yefan

TaO{sub x}-based resistive random access memory (RRAM) attracts considerable attention for the development of next generation nonvolatile memories. However, read current noise in RRAM is one of the critical concerns for storage application, and its microscopic origin is still under debate. In this work, the read current noise in TaO{sub x}-based RRAM was studied thoroughly. Based on a noise power spectral density analysis at room temperature and at ultra-low temperature of 25 K, discrete random telegraph noise (RTN) and continuous average current fluctuation (ACF) are identified and decoupled from the total read current noise in TaO{sub x} RRAM devices. A statisticalmore » comparison of noise amplitude further reveals that ACF depends strongly on the temperature, whereas RTN is independent of the temperature. Measurement results combined with conduction mechanism analysis show that RTN in TaO{sub x} RRAM devices arises from electron trapping/detrapping process in the hopping conduction, and ACF is originated from the thermal activation of conduction centers that form the percolation network. At last, a unified model in the framework of hopping conduction is proposed to explain the underlying mechanism of both RTN and ACF noise, which can provide meaningful guidelines for designing noise-immune RRAM devices.« less

Multidimensional Cyclic Voltammetry Simulations of Pseudocapacitive Electrodes with a Conducting Nanorod Scaffold

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

Mei, Bing-Ang; Li, Bin; Lin, Jie

This paper aims to understand the effect of nanoarchitecture on the performance of pseudocapacitive electrodes consisting of conducting scaffold coated with pseudocapacitive material. To do so, two-dimensional numerical simulations of ordered conducting nanorods coated with a thin film of pseudocapacitive material were performed. The simulations reproduced three-electrode cyclic voltammetry measurements based on a continuum model derived from first principles. Two empirical approaches commonly used experimentally to characterize the contributions of surface-controlled and diffusion-controlled charge storage mechanisms to the total current density with respect to scan rate were theoretically validated for the first time. Moreover, the areal capacitive capacitance, attributed tomore » EDL formation, remained constant and independent of electrode dimensions, at low scan rates. However, at high scan rates, it decreased with decreasing conducting nanorod radius and increasing pseudocapacitive layer thickness due to resistive losses. By contrast, the gravimetric faradaic capacitance, due to reversible faradaic reactions, decreased continuously with increasing scan rate and pseudocapacitive layer thickness but was independent of conducting nanorod radius. Note that the total gravimetric capacitance predicted numerically featured values comparable to experimental measurements. Finally, an optimum pseudocapacitive layer thickness that maximizes total areal capacitance was identified as a function of scan rate and confirmed by scaling analysis.« less

Multidimensional Cyclic Voltammetry Simulations of Pseudocapacitive Electrodes with a Conducting Nanorod Scaffold

DOE PAGES

Mei, Bing-Ang; Li, Bin; Lin, Jie; ...

2017-10-27

This paper aims to understand the effect of nanoarchitecture on the performance of pseudocapacitive electrodes consisting of conducting scaffold coated with pseudocapacitive material. To do so, two-dimensional numerical simulations of ordered conducting nanorods coated with a thin film of pseudocapacitive material were performed. The simulations reproduced three-electrode cyclic voltammetry measurements based on a continuum model derived from first principles. Two empirical approaches commonly used experimentally to characterize the contributions of surface-controlled and diffusion-controlled charge storage mechanisms to the total current density with respect to scan rate were theoretically validated for the first time. Moreover, the areal capacitive capacitance, attributed tomore » EDL formation, remained constant and independent of electrode dimensions, at low scan rates. However, at high scan rates, it decreased with decreasing conducting nanorod radius and increasing pseudocapacitive layer thickness due to resistive losses. By contrast, the gravimetric faradaic capacitance, due to reversible faradaic reactions, decreased continuously with increasing scan rate and pseudocapacitive layer thickness but was independent of conducting nanorod radius. Note that the total gravimetric capacitance predicted numerically featured values comparable to experimental measurements. Finally, an optimum pseudocapacitive layer thickness that maximizes total areal capacitance was identified as a function of scan rate and confirmed by scaling analysis.« less

A Fiber-Optic Aircraft Lightning Current Measurement Sensor

NASA Technical Reports Server (NTRS)

Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.

2013-01-01

A fiber-optic current sensor based on the Faraday Effect is developed for aircraft installations. It can measure total lightning current amplitudes and waveforms, including continuing current. Additional benefits include being small, lightweight, non-conducting, safe from electromagnetic interference, and free of hysteresis and saturation. The Faraday Effect causes light polarization to rotate in presence of magnetic field in the direction of light propagation. Measuring the total induced light polarization change yields the total current enclosed. The system operates at 1310nm laser wavelength and can measure approximately 300 A - 300 kA, a 60 dB range. A reflective polarimetric scheme is used, where the light polarization change is measured after a round-trip propagation through the fiber. A two-detector setup measures the two orthogonal polarizations for noise subtraction and improved dynamic range. The current response curve is non-linear and requires a simple spline-fit correction. Effects of high current were achieved in laboratory using combinations of multiple fiber and wire loops. Good result comparisons against reference sensors were achieved up to 300 kA. Accurate measurements on a simulated aircraft fuselage and an internal structure illustrate capabilities that maybe difficult with traditional sensors. Also tested at a commercial lightning test facility from 20 kA to 200 kA, accuracy within 3-10% was achieved even with non-optimum setups.

Self-Esteem & Academic Performance among University Students

ERIC Educational Resources Information Center

Arshad, Muhammad; Zaidi, Syed Muhammad Imran Haider; Mahmood, Khalid

2015-01-01

The current study was conducted to assess the self-esteem and academic performance among university students after arising of several behavioral and educational problems. A total number of 80 students, 40 male students and 40 female students were selected through purposive sampling from G. C. University Faisalabad. The participants were…

Disease evaluations and agronomic traits of advanced peanut breeding lines in 2017

USDA-ARS?s Scientific Manuscript database

Disease evaluations of advanced peanut breeding lines are conducted annually to compare the agronomic traits (crop value, yield, seed grade and characteristics) and disease resistance in cultivars that are currently available or close to being released for the Southwest. In 2017, a total of 19 comm...

Self-Report Measures of Juvenile Psychopathic Personality Traits: A Comparative Review

ERIC Educational Resources Information Center

Vaughn, Michael G.; Howard, Matthew O.

2005-01-01

The authors evaluated self-report instruments currently being used to assess children and adolescents with psychopathic personality traits with respect to their reliability, validity, and research utility. Comprehensive searches across multiple computerized bibliographic databases were conducted and supplemented with manual searches. A total of 30…

Successful Supervised Agricultural Experience Programs as Defined by American FFA Degree Star Finalists

ERIC Educational Resources Information Center

Rubenstein, Eric D.; Thorn, Andrew C.

2014-01-01

Within school-based agricultural education, supervised agricultural experience (SAE) programs remain an integral component of the total program. However, researchers have reported that SAE programs lack focus and direction. Furthermore, SAE programs lack a current definition of successful SAE programs. This study was conducted utilizing…

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…

Fourier analysis of polar cap electric field and current distributions

NASA Technical Reports Server (NTRS)

Barbosa, D. D.

1984-01-01

A theoretical study of high-latitude electric fields and currents, using analytic Fourier analysis methods, is conducted. A two-dimensional planar model of the ionosphere with an enhanced conductivity auroral belt and field-aligned currents at the edges is employed. Two separate topics are treated. A field-aligned current element near the cusp region of the polar cap is included to investigate the modifications to the convection pattern by the east-west component of the interplanetary magnetic field. It is shown that a sizable one-cell structure is induced near the cusp which diverts equipotential contours to the dawnside or duskside, depending on the sign of the cusp current. This produces characteristic dawn-dusk asymmetries to the electric field that have been previously observed over the polar cap. The second topic is concerned with the electric field configuration obtained in the limit of perfect shielding, where the field is totally excluded equatorward of the auroral oval. When realistic field-aligned current distributions are used, the result is to produce severely distorted, crescent-shaped equipotential contours over the cap. Exact, analytic formulae applicable to this case are also provided.

Laboratory and Field Evaluation of Rapid Setting Cementitious Materials for Large Crater Repair

DTIC Science & Technology

2010-05-01

frame used within which to complete the repair was the current NATO standard of 4 hr. A total of 6 simulated craters were prepared, with each repair...Combat Command 129 Andrews Street Langley Air Force Base, VA 23665 ERDC TR-10-4 ii Abstract: Current practice for expedient runway repair...penalty. Numerous commercial products are available. A full-scale field test was conducted using rapid setting materials to repair simulated bomb craters

[Cost of mother-child care in Morelos State].

PubMed

Cahuana-Hurtado, Lucero; Sosa-Rubí, Sandra; Bertozzi, Stefano

2004-01-01

To compare the cost of maternal and child health care (current model) to that of the WHO Mother-Baby Package if it were implemented. A pilot cross-sectional case study was conducted in September 2001 in Sanitary District No. III, Morelos State, Mexico. Two rural health centers, an urban health center, and a general hospital, all managed by the Ministry of Health, were selected for the study. The Mother-Baby Package Costing Spreadsheet was used to estimate the total cost and cost per intervention for the current model and for the Mother-Baby Package model. The total cost of the Mother-Baby Package was twice the cost of the current model. Of the 18 interventions evaluated, the highest proportion of total costs corresponded to antenatal care and normal delivery. Personnel costs represented more than half of the total costs. The Mother-Baby Package Costing Spreadsheet is a practical tool to estimate and compare costs and is useful to guide the distribution of financial resources allocated to maternal and child healthcare. However, this model has limited application unless it is adapted to the structure of each healthcare system. The English version of this paper is available at: http://www.insp.mx/salud/index.html.

Sodium and potassium conductance changes during a membrane action potential

PubMed Central

Bezanilla, Francisco; Rojas, Eduardo; Taylor, Robert E.

1970-01-01

1. A method for turning a membrane potential control system on and off in less than 10 μsec is described. This method was used to record membrane currents in perfused giant axons from Dosidicus gigas and Loligo forbesi after turning on the voltage clamp system at various times during the course of a membrane action potential. 2. The membrane current measured just after the capacity charging transient was found to have an almost linear relation to the controlled membrane potential. 3. The total membrane conductance taken from these current—voltage curves was found to have a time course during the action potential similar to that found by Cole & Curtis (1939). 4. The instantaneous current voltage curves were linear enough to make it possible to obtain a good estimate of the individual sodium and potassium channel conductances, either algebraically or by clamping to the sodium, or potassium, reversal potentials. Good general agreement was obtained with the predictions of the Hodgkin—Huxley equations. 5. We consider these results to constitute the first direct experimental demonstration of the conductance changes to sodium and potassium during the course of an action potential. PMID:5505231

UCB current detector experiment on Swedish auroral payloads. [ionospheric current and plasma flow measurements

NASA Technical Reports Server (NTRS)

Mozer, F.

1974-01-01

A split Langmuir probe has been developed to make in situ measurements of ionospheric current density and plasma bulk flow. The probe consists of two conducting elements that are separated by a thin insulator that shield each other over a 2 pi solid angle, and that are simultaneously swept from negative to positive with respect to the plasma. By measuring the current to each plate and the difference current between plates, information is obtained on the plasma's current density, bulk flow, electron temperature, and density. The instrument was successfully flown twice on sounding rockets into auroral events. Measurement data indicate that the total auroral current configuration is composed of several alternating east and west electrojets associated with several alternating up and down Birkeland currents.

Influence of anisotropic conductivity in the skull and white matter on transcranial direct current stimulation via an anatomically realistic finite element head model

NASA Astrophysics Data System (ADS)

Suh, Hyun Sang; Lee, Won Hee; Kim, Tae-Seong

2012-11-01

To establish safe and efficient transcranial direct current stimulation (tDCS), it is of particular importance to understand the electrical effects of tDCS in the brain. Since the current density (CD) and electric field (EF) in the brain generated by tDCS depend on various factors including complex head geometries and electrical tissue properties, in this work, we investigated the influence of anisotropic conductivity in the skull and white matter (WM) on tDCS via a 3D anatomically realistic finite element head model. We systematically incorporated various anisotropic conductivity ratios into the skull and WM. The effects of anisotropic tissue conductivity on the CD and EF were subsequently assessed through comparisons to the conventional isotropic solutions. Our results show that the anisotropic skull conductivity significantly affects the CD and EF distribution: there is a significant reduction in the ratio of the target versus non-target total CD and EF on the order of 12-14%. In contrast, the WM anisotropy does not significantly influence the CD and EF on the targeted cortical surface, only on the order of 1-3%. However, the WM anisotropy highly alters the spatial distribution of both the CD and EF inside the brain. This study shows that it is critical to incorporate anisotropic conductivities in planning of tDCS for improved efficacy and safety.

Associations Between Pharmacy Students’ Attitudes Toward Debt, Stress, and Student Loans

PubMed Central

Spivey, Christina A.; Jaeger, Melanie C.; Williams, Jennifer

2017-01-01

Objective. To assess graduating pharmacy students’ attitudes toward debt and determine associations with stress, student loan debt, financial need, current employment, post-graduation plans, and expected length of time to repay loans. Methods. Survey was conducted using an attitudes-toward-debt scale (sub-scales: tolerant attitudes toward debt; contemplation and knowledge about loans; fear of debt), Perceived Stress Scale, and questions concerning current employment, estimated total student loan debt, post-graduation plans, and expected length of time to repay loans. Federal loan data were collected using financial aid records. Independent samples t-test, ANOVA, and Pearson’s r correlations were conducted. Results. There were 147 students (96.7%) who participated. The majority were female (59.2%), white (69.4%), and had federal student loans (90.5%). Mean total loan amount was $153,276 (SD $59,810), which included federal students loans accumulated before and during pharmacy school. No significant differences were noted on attitudes toward debt or stress based on whether respondents had federal student loans. Greater “fear of debt” was correlated with increased stress, estimated total student loan debt, total federal loan debt, and pharmacy school loan debt. Greater “contemplation and knowledge about loans” was correlated with lower estimated total student loan debt, total federal loan amount, and pharmacy school loan amount. Students with higher “contemplation and knowledge” scores expected to repay loans within a shorter time frame than students with lower scores. Conclusion. Increased fear of debt was related to greater perceived stress and higher student loan amounts borrowed, while increased contemplation and knowledge about loans was associated with lower amounts borrowed. Educational programming concerning loans, debt, and personal financial management may help reduce stress and amount borrowed. PMID:29109558

Associations Between Pharmacy Students' Attitudes Toward Debt, Stress, and Student Loans.

PubMed

Chisholm-Burns, Marie A; Spivey, Christina A; Jaeger, Melanie C; Williams, Jennifer

2017-09-01

Objective. To assess graduating pharmacy students' attitudes toward debt and determine associations with stress, student loan debt, financial need, current employment, post-graduation plans, and expected length of time to repay loans. Methods. Survey was conducted using an attitudes-toward-debt scale (sub-scales: tolerant attitudes toward debt; contemplation and knowledge about loans; fear of debt), Perceived Stress Scale, and questions concerning current employment, estimated total student loan debt, post-graduation plans, and expected length of time to repay loans. Federal loan data were collected using financial aid records. Independent samples t -test, ANOVA, and Pearson's r correlations were conducted. Results. There were 147 students (96.7%) who participated. The majority were female (59.2%), white (69.4%), and had federal student loans (90.5%). Mean total loan amount was $153,276 (SD $59,810), which included federal students loans accumulated before and during pharmacy school. No significant differences were noted on attitudes toward debt or stress based on whether respondents had federal student loans. Greater "fear of debt" was correlated with increased stress, estimated total student loan debt, total federal loan debt, and pharmacy school loan debt. Greater "contemplation and knowledge about loans" was correlated with lower estimated total student loan debt, total federal loan amount, and pharmacy school loan amount. Students with higher "contemplation and knowledge" scores expected to repay loans within a shorter time frame than students with lower scores. Conclusion. Increased fear of debt was related to greater perceived stress and higher student loan amounts borrowed, while increased contemplation and knowledge about loans was associated with lower amounts borrowed. Educational programming concerning loans, debt, and personal financial management may help reduce stress and amount borrowed.

Fiber-Optic Sensor for Aircraft Lightning Current Measurement

NASA Technical Reports Server (NTRS)

Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George G.; Mata, Carlos T.; Mata,Angel G.; Snyder, Gary P.

2012-01-01

An electric current sensor based on Faraday rotation effect in optical fiber was developed for measuring aircraft lightning current. Compared to traditional sensors, the design has many advantages including the ability to measure total current and to conform to structure geometries. The sensor is also small, light weight, non-conducting, safe from interference, and free of hysteresis and saturation. Potential applications include characterization of lightning current waveforms, parameters and paths, and providing environmental data for aircraft certifications. In an optical fiber as the sensing medium, light polarization rotates when exposed to a magnetic field in the direction of light propagation. By forming closed fiber loops around a conductor and applying Ampere s law, measuring the total light rotation yields the enclosed current. A reflective polarimetric scheme is used, where polarization change is measured after the polarized light travels round-trip through the sensing fiber. The sensor system was evaluated measuring rocket-triggered lightning over the 2011 summer. Early results compared very well against a reference current shunt resistor, demonstrating the sensor's accuracy and feasibility in a lightning environment. While later comparisons show gradually increasing amplitude deviations for an undetermined cause, the overall waveforms still compared very well.

Fiber-Optic Sensor for Aircraft Lightning Current Measurement

NASA Technical Reports Server (NTRS)

Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George G.; Mata, Carlos T.; Mata, Angel G.; Snyder, Gary P.

2012-01-01

An electric current sensor based on Faraday rotation effect in optical fiber was developed for measuring aircraft lightning current. Compared to traditional sensors, the design has many advantages including the ability to measure total current and to conform to structure geometries. The sensor is also small, light weight, non-conducting, safe from interference, and free of hysteresis and saturation. Potential applications include characterization of lightning current waveforms, parameters and paths, and providing environmental data for aircraft certifications. In an optical fiber as the sensing medium, light polarization rotates when exposed to a magnetic field in the direction of light propagation. By forming closed fiber loops around a conductor and applying Ampere s law, measuring the total light rotation yields the enclosed current. A reflective polarimetric scheme is used, where polarization change is measured after the polarized light travels round-trip through the sensing fiber. The sensor system was evaluated measuring rocket-triggered lightning over the 2011 summer. Early results compared very well against a reference current shunt resistor, demonstrating the sensor s accuracy and feasibility in a lightning environment. While later comparisons show gradually increasing amplitude deviations for an undetermined cause, the overall waveforms still compared very well.

Availability of yellow pine sawtimber in Alabama

Treesearch

William H. McWilliams

1991-01-01

Alabama's timberland supports 76.2 billion board feet of sawtimber (International 1/4-inch Rule), of which 55 percent is contributed by yellow pine species. Currently, yellow pine sawtimber volume totals 41.8 billion board feet. The recent inventory conducted by the USDA-Forest Service, Southern Forest Experiment Station, Forest Inventory and Analysis Unit (SO-...

Negotiating Lesbian Family Identity via Symbols and Rituals

ERIC Educational Resources Information Center

Suter, Elizabeth A.; Daas, Karen L.; Bergen, Karla Mason

2008-01-01

This study reports how lesbian families negotiate their family identities via symbols and rituals. Sixteen couple interviews were conducted with lesbian co-mothers (for a total of 32 participants) who had their children via donor insemination in the contexts of their current same-sex relationships. Interviews were analyzed using grounded theory.…

Lithuanian University Students' Knowledge of Biotechnology and Their Attitudes to the Taught Subject

ERIC Educational Resources Information Center

Lamanauskas, Vincentas; Makarskaite-Petkeviciene, Rita

2008-01-01

The impact of genetic engineering on peoples' everyday life has become present reality. In order to establish the level of the available schoolchildren and university students' knowledge of biotechnology, various investigations have been conducted. However, the current situation in Lithuania remains unclear. A total of 287 students--pre-service…

Inclusive Education in an International School: A Case Study from Hong Kong

ERIC Educational Resources Information Center

Chan, Twiggy; Yuen, Mantak

2015-01-01

This case study provides an overview of current policy, practices and problems concerning inclusion in one international secondary school in Hong Kong. A total of 13 interviews were conducted with the school management team, teachers, students and parents, supplemented by 12 classroom observations and two "student-shadowing" exercises.…

Influence of topological transitions in a quantizing magnetic field and anisotropy of current carrier scattering by acoustic phonons on the longitudinal electrical conductivity of layered crystals with open fermi surfaces

NASA Astrophysics Data System (ADS)

Gorskii, P. V.

2011-03-01

It is demonstrated that the dependence of Fermi's energy on the magnetic field causes a set of the Shubnikov - de Haas (SDH) oscillation frequencies to change, and their relative contribution to the total longitudinal conductivity of layered crystals depends on whether the scattering of current carriers is isotropic or anisotropic. Owing to the topological transition in a strong magnetic field, Fermi's surface (FS) is transformed from open into closed one and is compressed in the magnetic field direction. Therefore, in an ultraquantum limit, disregarding the Dingle factor, the longitudinal electrical conductivity of the layered crystal tends to zero as a reciprocal square of the magnetic field for the isotropic scattering and as a reciprocal cube of the magnetic field for the anisotropic scattering. All calculations are performed in the approximation of relaxation time considered to be constant versus the quantum numbers for the isotropic scattering and proportional to the longitudinal velocity of current carriers for the anisotropic scattering.

Critical Appraisal of the Quality of Evidence Addressing the Diagnosis, Prognosis, and Management of Peripheral Artery Disease in Patients With Diabetic Foot Ulceration.

PubMed

Ali, Stephen R; Ozdemir, Baris A; Hinchliffe, Robert J

2018-06-13

There is a paucity of robust evidence on prevention and management of diabetic foot ulcers (DFUs) to inform treatment. This study appraises the current quality of the evidence addressing diagnosis, prognosis, and management of peripheral artery disease (PAD) in patients with DFUs using a newly devised 21 point scoring (TOPS) disease specific research appraisal tool published by the International Working Group on the Diabetic Foot (IWGDF) and European Wound Management Association. The 2015 IWGDF guidance on diagnosis, prognosis, and management of PAD in patients with DFUs was used to identify studies pertaining to prevention and management. Two reviewers assessed these articles against TOPS, which examines study design, conduct, and outcome reporting. The overall median score was 8 (3-12/21). The median design total score was 2 (0-4/11). The median conduct total score was 2 (1-4/6). The median outcomes total score was 3 (1-4/4). There was improvement with time in overall total (Spearman Rho 0.39, p = .0005), design total (0.35, p = .0023), and outcomes total (0.35, p = .0002), but not conduct total (-0.03, p = .8132) scores. Although this analysis revealed an improvement over time in the overall calibre of studies, the present quality remains poor on which to inform the diagnosis, management, and prognosis of patients with PAD and diabetic foot ulceration. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.

Low resistance, large dimension entrance to the inner cavity of BK channels determined by changing side-chain volume

PubMed Central

Niu, Xiaowei

2011-01-01

Large-conductance Ca2+- and voltage-activated K+ (BK) channels have the largest conductance (250–300 pS) of all K+-selective channels. Yet, the contributions of the various parts of the ion conduction pathway to the conductance are not known. Here, we examine the contribution of the entrance to the inner cavity to the large conductance. Residues at E321/E324 on each of the four α subunits encircle the entrance to the inner cavity. To determine if 321/324 is accessible from the inner conduction pathway, we measured single-channel current amplitudes before and after exposure and wash of thiol reagents to the intracellular side of E321C and E324C channels. MPA− increased currents and MTSET+ decreased currents, with no difference between positions 321 and 324, indicating that side chains at 321/324 are accessible from the inner conduction pathway and have equivalent effects on conductance. For neutral amino acids, decreasing the size of the entrance to the inner cavity by substituting large side-chain amino acids at 321/324 decreased outward single-channel conductance, whereas increasing the size of the entrance with smaller side-chain substitutions had little effect. Reductions in outward conductance were negated by high [K+]i. Substitutions had little effect on inward conductance. Fitting plots of conductance versus side-chain volume with a model consisting of one variable and one fixed resistor in series indicated an effective diameter and length of the entrance to the inner cavity for wild-type channels of 17.7 and 5.6 Å, respectively, with the resistance of the entrance ∼7% of the total resistance of the conduction pathway. The estimated dimensions are consistent with the structure of MthK, an archaeal homologue to BK channels. Our observations suggest that BK channels have a low resistance, large entrance to the inner cavity, with the entrance being as large as necessary to not limit current, but not much larger. PMID:21576375

Current to the ionosphere following a lightning stroke

NASA Technical Reports Server (NTRS)

Hale, L. C.; Baginski, M. E.

1987-01-01

A simple analytical expression for calculating the total current waveform to the ionosphere after a lightning stroke is derived. The validity of this expression is demonstrated by comparison with a more rigorous computer solution of Maxwell's equations. The analytic model demonstrates that the temporal variation of the current induced in the ionosphere and global circuit and the corresponding return current in the earth depends on the conductivity profile at intervening altitudes in the middle atmosphere. A conclusion is that capacitative coupling may provide tighter coupling between the lower atmosphere and the ionosphere than usually considered, in both directions, which may help to explain observations which seem to indicate that magnetospheric phenomena may in some instances trigger lightning.

Environmentally Compliant Coating Remover Evaluation

DTIC Science & Technology

2012-08-30

22 9 Total of 491 products evaluated 7 Background • Many DoD depainting operations currently use environmentally compliant peroxide -assisted... benzyl alcohol strippers • These strippers have acceptable coating removal rates with minimal physical damage to metallic substrates • However, several...Coatings • Environmentally compliant benzyl alcohol product • Passed corrosion testing conducted by SMI in 2011 11 Laboratory Testing Scope

Mental Health among Children and Young Adults with Visual Impairments: A Systematic Review

ERIC Educational Resources Information Center

Augestad, Liv Berit

2017-01-01

Introduction: The purpose of this study was to summarize current scientific knowledge relating to the occurrence of mood disorders among children with visual impairments. Methods: A systematic review was conducted of articles published between January1998 and July 2016, inclusive. A total of 17 publications met the inclusion criteria, of which 15…

A Survey on the Use of Mobile Applications for People Who Are Visually Impaired

ERIC Educational Resources Information Center

Griffin-Shirley, Nora; Banda, Devender R.; Ajuwon, Paul M.; Cheon, Jongpil; Lee, Jaehoon; Park, Hye Ran; Lyngdoh, Sanpalei N.

2017-01-01

Introduction: The literature indicates that few studies have been conducted with persons with visual impairments (that is, those who are blind or have low vision) concerning mobile application or "app" usage. The current study explores the use of mobile apps with this population globally. Methods: A total of 259 participants with visual…

Skills and Knowledge Needs among Recent Bioscience Graduates--How Do Our Courses Measure Up?

ERIC Educational Resources Information Center

Brown, Colin A.; Calvert, Jane; Charman, Paul; Newton, Chris; Wiles, Kathy; Hughes, Ian

2005-01-01

A telephone survey was conducted of 2002 or 2003 graduates (942 in total) from various bioscience degree programmes at 4 universities. A structured and scripted interview determined: title/class of degree; nature of current occupation (unemployed, further degree, job) and if regarded as "career related" post or just "filling in"; if current…

A Multimethod Multitrait Validity Assessment of Self-Construal in Japan, Korea, and the United States

ERIC Educational Resources Information Center

Bresnahan, Mary J.; Levine, Timothy R.; Shearman, Sachiyo Morinaga; Lee, Sun Young; Park, Cheong-Yi; Kiyomiya, Toru

2005-01-01

A large number of previous studies have used self-construal to predict communication outcomes. Recent evidence, however, suggests that validity problems may exist in self-construal measurement. The current study conducted a multimethod multitrait (Campbell & Fiske, 1959) validation study of self-construal measures with data (total N = 578)…

Water quality of the lower Columbia River basin; analysis of current and historical water-quality data through 1994

USGS Publications Warehouse

Fuhrer, Gregory J.; Tanner, Dwight Q.; Morace, Jennifer L.; McKenzie, Stuart W.; Skach, Kenneth A.

1996-01-01

Trend tests showed significant (r < 0.05) downward trends from 1973 to 1994 for three constituents at the Columbia River at Warrendale: phosphorus in unfiltered water, total dissolved solids, and specific conductance. These trends may be a consequence of more conservative agricultural practices in the area upstream from Warrendale.

Enhanced Performance of Streamline-Traced External-Compression Supersonic Inlets

NASA Technical Reports Server (NTRS)

Slater, John W.

2015-01-01

A computational design study was conducted to enhance the aerodynamic performance of streamline-traced, external-compression inlets for Mach 1.6. The current study explored a new parent flowfield for the streamline tracing and several variations of inlet design factors, including the axial displacement and angle of the subsonic cowl lip, the vertical placement of the engine axis, and the use of porous bleed in the subsonic diffuser. The performance was enhanced over that of an earlier streamline-traced inlet such as to increase the total pressure recovery and reduce total pressure distortion

A mathematical model for predicting cyclic voltammograms of electronically conductive polypyrrole

NASA Technical Reports Server (NTRS)

Yeu, Taewhan; Nguyen, Trung V.; White, Ralph E.

1988-01-01

Polypyrrole is an attractive polymer for use as a high-energy-density secondary battery because of its potential as an inexpensive, lightweight, and noncorrosive electrode material. A mathematical model to simulate cyclic voltammograms for polypyrrole is presented. The model is for a conductive porous electrode film on a rotating disk electrode (RDE) and is used to predict the spatial and time dependence of concentration, overpotential, and stored charge profiles within a polypyrrole film. The model includes both faradic and capacitance charge components in the total current density expression.

A mathematical model for predicting cyclic voltammograms of electronically conductive polypyrrole

NASA Technical Reports Server (NTRS)

Yeu, Taewhan; Nguyen, Trung V.; White, Ralph E.

1987-01-01

Polypyrrole is an attractive polymer for use as a high-energy-density secondary battery because of its potential as an inexpensive, lightweight, and noncorrosive electrode material. A mathematical model to simulate cyclic voltammograms for polypyrrole is presented. The model is for a conductive porous electrode film on a rotating disk electrode (RDE) and is used to predict the spatial and time dependence of concentration, overpotential, and stored charge profiles within a polypyrrole film. The model includes both faradic and capacitance charge components in the total current density expression.

Biogas production from pineapple core - A preliminary study

NASA Astrophysics Data System (ADS)

Jehan, O. S.; Sanusi, S. N. A.; Sukor, M. Z.; Noraini, M.; Buddin, M. M. H. S.; Hamid, K. H. K.

2017-09-01

Anaerobic digestion of pineapple waste was investigated by using pineapple core as the sole substrate. Pineapple core was chosen due to its high total sugar content thus, indicating high amount of fermentable sugar. As digestion process requires the involvement of microorganisms, wastewater from the same industry was added in the current study at ratio of 1:1 by weight. Two different sources of wastewater (Point 1 and Point 2) were used in this study to distinguish the performance of microorganism consortia in both samples. The experiment was conducted by using a lab scale batch anaerobic digester made up from 5L container with separate gas collecting system. The biogas produced was collected by using water displacement method. The experiment was conducted for 30 days and the biogas produced was collected and its volume was recorded at 3 days interval. Based on the data available, wastewater from the first point recorded higher volume of biogas with the total accumulated biogas volume is 216.1 mL. Meanwhile, wastewater sample from Point 2 produced a total of 140.5 mL of biogas, by volume. The data shows that the origin and type of microorganism undeniably play significant role in biogas production. In fact, other factors; pH of wastewater and temperature were also known to affect biogas production. The anaerobic digestion is seen as the promising and sustainable alternatives to current disposal method.

Current observations offshore Punta Tuna, Puerto Rico, 21 June-7 December 1980. Part A

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

Frye, D.; Leavitt, K.; Whitney, A.

1981-08-01

An oceanographic measurement program was conducted in the vicinity of a proposed ocean thermal energy conversion (OTEC) site about 20 km offshore of Punta Tuna, Puerto Rico. As part of the program, a mooring consisting of five current meters was maintained between 21 June and 7 December, 1980. The current data collected are summarized according to frequency of occurrence within 5 cm/sec speed and 15/sup 0/ direction intervals. Sums and percentages of total occurrence are given for each speed and direction class, along with mean speed, extreme speeds, mean component speeds, and standard deviations. Hourly averages of current speed, truemore » direction, current vector, temperature, and pressure are plotted as a function of time. On 13 December, 1980, a current meter array was deployed at the Punta Tuna site and recovered on May 16, 1981. The processed current data from this current meter array are described. (LEW)« less

A new approach to the method of source-sink potentials for molecular conduction

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

Pickup, Barry T., E-mail: B.T.Pickup@sheffield.ac.uk, E-mail: P.W.Fowler@sheffield.ac.uk; Fowler, Patrick W., E-mail: B.T.Pickup@sheffield.ac.uk, E-mail: P.W.Fowler@sheffield.ac.uk; Borg, Martha

2015-11-21

We re-derive the tight-binding source-sink potential (SSP) equations for ballistic conduction through conjugated molecular structures in a form that avoids singularities. This enables derivation of new results for families of molecular devices in terms of eigenvectors and eigenvalues of the adjacency matrix of the molecular graph. In particular, we define the transmission of electrons through individual molecular orbitals (MO) and through MO shells. We make explicit the behaviour of the total current and individual MO and shell currents at molecular eigenvalues. A rich variety of behaviour is found. A SSP device has specific insulation or conduction at an eigenvalue ofmore » the molecular graph (a root of the characteristic polynomial) according to the multiplicities of that value in the spectra of four defined device polynomials. Conduction near eigenvalues is dominated by the transmission curves of nearby shells. A shell may be inert or active. An inert shell does not conduct at any energy, not even at its own eigenvalue. Conduction may occur at the eigenvalue of an inert shell, but is then carried entirely by other shells. If a shell is active, it carries all conduction at its own eigenvalue. For bipartite molecular graphs (alternant molecules), orbital conduction properties are governed by a pairing theorem. Inertness of shells for families such as chains and rings is predicted by selection rules based on node counting and degeneracy.« less

Effect of laryngotracheal topical anesthesia on recurrent laryngeal nerve monitoring during thyroid Surgery.

PubMed

Pachuski, Justin; Vaida, Sonia; Donahue, Kathleen; Roberts, John; Kunselman, Allen; Oberman, Benjamin; Patel, Hetal; Goldenberg, David

2016-03-01

Intraoperative neuromonitoring of the recurrent laryngeal nerve (RLN) is often used as an adjunct for RLN identification and preservation during thyroidectomies. Laryngotracheal anesthesia (LTA) with topical lidocaine reduces coughing upon emergence from anesthesia and in the immediate postoperative period; however, its use is prohibited with concerns that it could decrease the sensitivity of the intraoperative neuromonitoring. We hypothesize that there is no difference in measurements of nerve conduction made before and after LTA administration. An observational study in which all patients were subjected to LTA administration was conducted. Recurrent laryngeal nerve threshold currents were measured before and after the intervention. Tertiary medical center operating room. Eighteen patients (total of 25 nerves at risk) with American Society of Anesthesiologists classes 1 to 3 undergoing thyroid surgery. After the thyroid was removed and threshold currents at the RLN were obtained, LTA with endotracheal lidocaine was applied on the left and right side of the in situ endotracheal tube (2 cc of 4% lidocaine per side). Threshold currents were reassessed at 5 and 10 minutes after LTA administration. Threshold currents (minimum stimulus current applied to the RLN required to generate a discernible electromyographic response at the vocal cords) were recorded along the RLN for a baseline at 5 and 10 mm from the insertion point of the RLN into the larynx. Threshold currents were reassessed at the same 2 positions on the RLN at 5 and 10 minutes after LTA administration. Differences in mean values, between threshold currents recorded at the 3 different times, at 2 positions on the RLN, were used to compare effects of LTA on nerve conduction. There were no statistically significant differences when comparing threshold currents before and after LTA administration. Laryngotracheal anesthesia had no significant effect on RLN nerve conduction in the period assessed. Copyright © 2016 Elsevier Inc. All rights reserved.

Enhanced wall-plug efficiency in AlGaN-based deep-ultraviolet light-emitting diodes with uniform current spreading p-electrode structures

NASA Astrophysics Data System (ADS)

Hao, Guo-Dong; Taniguchi, Manabu; Tamari, Naoki; Inoue, Shin-ichiro

2016-06-01

The current crowding is an especially severe issue in AlGaN-based deep-ultraviolet (DUV) light-emitting diodes (LEDs) because of the low conductivity of the n-AlGaN cladding layer that has a high Al fraction. We theoretically investigated the improvement in internal quantum efficiency and total resistances in DUV-LEDs with an emission wavelength of 265 nm by a well-designed p-electrode geometry to produce uniform current spreading. As a result, the wall-plug efficiency was enhanced by a factor of 60% at an injection current of 350 mA in the designed uniform-current-spreading p-electrode LED when compared with an LED with a conventional cross-bar p-electrode pattern.

Current status of managing food allergies in schools in Seoul, Korea.

PubMed

Kim, Soyoung; Yoon, Jihyun; Kwon, Sooyoun; Kim, Jihyun; Han, Youngshin

2012-12-01

Recently the need to manage food allergies in schools has been growing. This study aimed to examine the current status of managing food allergies in schools in Seoul, Korea. A questionnaire survey was conducted in cooperation with the School Dietician Association during April 2009. Among the participating 154 schools, a total of 109 (71%) were determining students' food allergy status through parental surveys based on self-reported food allergies. A total of 72 (47%) had experienced student visits to a school health room due to food allergies within one year before the survey. Over 80 percent of the schools relied on self-care only without any school-wide measures for food allergies in place. Among the 890 menu items most frequently served in school lunch programs, a total of 664 (75%) were found to contain more than one food allergen. It is highly suggested that preventive plans and treatment measures should be established to manage food allergies in schools.

Extra-high voltage transmission lines: mechanisms of biological effects on honeybees. Final report

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

Greenberg, B.; Bindokas, V.

1985-08-01

The authors confirmed that bee exposure to E fields, including 100 kV/m, under the dry conditions cause no detectable effect on colony behavior. If, however, exposure occurs when moisture is present, or if bees are on a conductive surface, they become visibly disturbed, mortality is increased, abnormal propolization occurs, and colony development may be impaired. It seems plausible that bees on conductive surfaces within a hive under a 765-kV/m transmission line can perceive shocks from body currents induced by enhanced intra-hive E fields. Hives exposed under a 765-kV/m transmission line to an ambient E field of 7 kV/m have internalmore » step-potential-induced currents and interchamber chort-circuit currents which range from one-half to several microamperes. Total hive currents can exceed 100 ..mu..A. Thus, induced hive currents exceed the empirical sting threshold by up to a factor of 100 and the E-field-induced body current by up to a factor of 1000. The degree of disturbance which could be produced by these intra-hive currents will eclipse that produced by perception of E-field-induced body currents. The authors therefore attribute the disturbance of colonies under a transmission line primarily to electric shock from induced hive currents. 10 refs., 51 figs., 18 tabs. (DT)« less

Lightning Current Measurement with Fiber-Optic Sensor

NASA Technical Reports Server (NTRS)

Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.; Mata, Carlos T.; Mata, Angel G.; Snyder, Gary P.

2014-01-01

A fiber-optic current sensor is successfully developed with many potential applications for electric current measurement. Originally developed for in-flight lightning measurement, the sensor utilizes Faraday Effect in an optical fiber. The Faraday Effect causes linear light polarization in a fiber to rotate when the fiber is exposed to a magnetic field. The polarization change is detected using a reflective polarimetric scheme. Forming fiber loops and applying Ampere's law, measuring the total light rotation results in the determination of the total current enclosed. The sensor is conformable to complex structure geometry. It is also non-conductive and immune to electromagnetic interference, saturation or hysteresis. Installation is non-intrusive, and the sensor can be safely routed through flammable areas. Two similar sensor systems are described in this paper. The first system operates at 1310nm laser wavelength and is capable of measuring approximately 300 A - 300 kA, a 60 dB range. Laboratory validation results of aircraft lighting direct and in-direct effect current amplitudes are reported for this sensor. The second system operates at 1550nm wavelength and can measure about 400 A - 400 kA. Triggered-lightning measurement data are presented for this system. Good results are achieved in all cases.

Fiber-Optic Current Sensor Validation with Triggered Lightning Measurements

NASA Technical Reports Server (NTRS)

Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.; Mata, Carlos T.; Mata, Angel G.; Snyder, Gary P.

2013-01-01

A fiber optic current sensor based on the Faraday Effect is developed that is highly suitable for aircraft installation and can measure total current enclosed in a fiber loop down to DC. Other attributes include being small, light-weight, non-conducting, safe from electromagnetic interference, and free of hysteresis and saturation. The Faraday Effect causes light polarization to rotate when exposed to a magnetic field in the direction of light propagation. Measuring the induced light polarization rotation in fiber loops yields the total current enclosed. Two sensor systems were constructed and installed at Camp Blanding, Florida, measuring rocket-triggered lightning. The systems were similar in design but with different laser wavelengths, sensitivities and ranges. Results are compared to a shunt resistor as reference. The 850nm wavelength system tested in summer 2011 showed good result comparison early. However, later results showed gradual amplitude increase with time, attributed to corroded connections affecting the 50-ohm output termination. The 1550nm system also yielded good results in the summer 2012. The successful measurements demonstrate the fiber optic sensor's accuracies in capturing real lightning currents, and represent an important step toward future aircraft installation.

Secondary Electron Emission Yields

NASA Technical Reports Server (NTRS)

Krainsky, I.; Lundin, W.; Gordon, W. L.; Hoffman, R. W.

1981-01-01

The secondary electron emission (SEE) characteristics for a variety of spacecraft materials were determined under UHV conditions using a commercial double pass CMA which permits sequential Auger electron electron spectroscopic analysis of the surface. The transparent conductive coating indium tin oxide (ITO) was examined on Kapton and borosilicate glass and indium oxide on FED Teflon. The total SEE coefficient ranges from 2.5 to 2.6 on as-received surfaces and from 1.5 to 1.6 on Ar(+) sputtered surfaces with 5 nm removed. A cylindrical sample carousel provides normal incidence of the primary beam as well as a multiple Faraday cup measurement of the approximately nA beam currents. Total and true secondary yields are obtained from target current measurements with biasing of the carousel. A primary beam pulsed mode to reduce electron beam dosage and minimize charging of insulating coatings was applied to Mg/F2 coated solar cell covers. Electron beam effects on ITO were found quite important at the current densities necessary to do Auger studies.

Does Parental Mediation of Media Influence Child Outcomes? A Meta-Analysis on Media Time, Aggression, Substance Use, and Sexual Behavior

ERIC Educational Resources Information Center

Collier, Kevin M.; Coyne, Sarah M.; Rasmussen, Eric E.; Hawkins, Alan J.; Padilla-Walker, Laura M.; Erickson, Sage E.; Memmott-Elison, Madison K.

2016-01-01

The current study examined how parental mediation of media (restrictive mediation, active mediation, and coviewing) influenced child outcomes. Three meta-analyses, 1 for each type of mediation, were conducted on a total of 57 studies. Each analysis assessed the effectiveness of parental mediation on 4 pertinent child outcomes: media use,…

Development and Validation of a Brief Version of the Dyadic Adjustment Scale With a Nonparametric Item Analysis Model

ERIC Educational Resources Information Center

Sabourin, Stephane; Valois, Pierre; Lussier, Yvan

2005-01-01

The main purpose of the current research was to develop an abbreviated form of the Dyadic Adjustment Scale (DAS) with nonparametric item response theory. The authors conducted 5 studies, with a total participation of 8,256 married or cohabiting individuals. Results showed that the item characteristic curves behaved in a monotonically increasing…

The Views of Student-Teachers Attending a Turkish University on Discrimination Related to the Education of Women

ERIC Educational Resources Information Center

Murat, Mehmet

2013-01-01

The current study aims to highlight how Turkish students perceive important issues such as discrimination against women, violence that surfaced as a result of discrimination, alienation, inequality between men and women and isolation of women from work life. A total of 50 students participated in the study. Individual interviews were conducted.…

Adaptation of General Belongingness Scale into Turkish for Adolescents: Validity and Reliability Studies

ERIC Educational Resources Information Center

Yildiz, Mehmet Ali

2017-01-01

The current research aims to adapt the General Belongingness Scale (GBS), developed by Malone, Pillow, and Osman (2012), into Turkish for adolescents and to conduct the validity and reliability studies for it. Ages of the participants, a total of 567 adolescents including 274 males (48.3%) and 293 females (51.7%) ranged between 14 and 18 (average…

Enhanced Performance of Streamline-Traced External-Compression Supersonic Inlets

NASA Technical Reports Server (NTRS)

Slater, John W.

2015-01-01

A computational design study was conducted to enhance the aerodynamic performance of streamline-traced, external-compression inlets for Mach 1.6. Compared to traditional external-compression, two-dimensional and axisymmetric inlets, streamline-traced inlets promise reduced cowl wave drag and sonic boom, but at the expense of reduced total pressure recovery and increased total pressure distortion. The current study explored a new parent flowfield for the streamline tracing and several variations of inlet design factors, including the axial displacement and angle of the subsonic cowl lip, the vertical placement of the engine axis, and the use of porous bleed in the subsonic diffuser. The performance was enhanced over that of an earlier streamline-traced inlet such as to increase the total pressure recovery and reduce total pressure distortion.

Sheath effects observed on a 10 meter high voltage panel in simulated low earth orbit plasma

NASA Technical Reports Server (NTRS)

Mccox, J. E.; Konradi, A.

1979-01-01

A large (1m x 10m) flat surface of conductive material was biased to high voltage (+ or - 3000 V) to simulate the behavior of a large solar array in low earth orbit. The model array was operated in a plasma environment of 1,000 to 1,000,000/cu cm, with sufficient free space around it for the resulting plasma sheaths to develop unimpeded for 5-10 meters into the surrounding plasma. Measurements of the resulting sheath thickness were obtained. The observed thickness varied approximately as V to the 3/4 power and N to the 1/2 power. This effect appears to limit total current leakage from the test array until sheath dimensions exceed about 1 meter. Total leakage current was also measured with the array.

Helping cancer patients to quit smoking by understanding their risk perception, behavior, and attitudes related to smoking.

PubMed

Li, William H C; Chan, Sophia S C; Lam, T H

2014-08-01

Evidence shows that smoking is a major cause of cancer, and cancer patients who continue smoking are at greater risk for all causes of mortality, cancer recurrence, and second primary cancers. Nevertheless, many cancer patients still smoke and are not willing to quit. This study aimed at understanding the needs and concerns of current and ex-smoking cancer patients, including their risk perceptions, and the behavior and attitudes related to smoking. A qualitative research was conducted in an oncology outpatient clinic. A one-to-one semi-structured interview was conducted with current Chinese smokers and ex-smokers after they had been diagnosed with cancer. Data saturation was achieved after interviewing a total of 20 current smokers and 20 ex-smokers. A total of 241 patients who were smokers prior to their diagnosis of cancer were identified. Of 241 patients, 208 (86.31%) quitted and 33 (13.69%) continued smoking after receiving a cancer diagnosis. In general, patients who refused to quit smoking subsequent to a cancer diagnosis thought that the perceived barriers to quitting outweighed the perceived benefits of quitting. In contrast, most cancer patients who quit after their cancer diagnoses thought that the perceived benefits of quitting greatly outweighed the perceived barriers to quitting. It is vital that healthcare professionals should help cancer patients to quit smoking. Understanding how current smokers and ex-smokers perceive the risks of smoking, and their behavior, attitudes, and experiences related to smoking is an essential prerequisite for the design of an effective smoking cessation intervention. Copyright © 2014 John Wiley & Sons, Ltd.

Contribution of Resting Conductance, GABAA-Receptor Mediated Miniature Synaptic Currents and Neurosteroid to Chloride Homeostasis in Central Neurons.

PubMed

Yelhekar, Tushar D; Druzin, Michael; Johansson, Staffan

2017-01-01

Maintenance of a low intraneuronal Cl - concentration, [Cl - ] i , is critical for inhibition in the CNS. Here, the contribution of passive, conductive Cl - flux to recovery of [Cl - ] i after a high load was analyzed in mature central neurons from rat. A novel method for quantifying the resting Cl - conductance, important for [Cl - ] i recovery, was developed and the possible contribution of GABA A and glycine receptors and of ClC-2 channels to this conductance was analyzed. The hypothesis that spontaneous, action potential-independent release of GABA is important for [Cl - ] i recovery was tested. [Cl - ] i was examined by gramicidin-perforated patch recordings in medial preoptic neurons. Cells were loaded with Cl - by combining GABA or glycine application with a depolarized voltage, and the time course of [Cl - ] i was followed by measurements of the Cl - equilibrium potential , as obtained from the current recorded during voltage ramps combined with GABA or glycine application. The results show that passive Cl - flux contributes significantly, in the same order of magnitude as does K + -Cl - cotransporter 2 (KCC2), to [Cl - ] i recovery and that Cl - conductance accounts for ∼ 6% of the total resting conductance. A major fraction of this resting Cl - conductance is picrotoxin (PTX)-sensitive and likely due to open GABA A receptors, but ClC-2 channels do not contribute. The results also show that when the decay of GABA A receptor-mediated miniature postsynaptic currents (minis) is slowed by the neurosteroid allopregnanolone, such minis may significantly quicken [Cl - ] i recovery, suggesting a possible steroid-regulated role for minis in the control of Cl - homeostasis.

Challenges and opportunities in building health research capacity in Tanzania: a case of the National Institute for Medical Research.

PubMed

Magesa, Stephen M; Mwape, Bonard; Mboera, Leonard E G

2011-12-01

Capacity building is considered a priority for health research institutions in developing countries to achieve the Millennium Development Goals by 2015. However, in many countries including Tanzania, much emphasis has been directed towards human resources for health with the total exclusion of human resources for health research. The objective of this study was to systematically investigate the capacity building process for the Tanzanian National Institute for Medical Research (NIMR) over a 30-year period and identify the challenges and opportunities in creating a critical mass of multi-disciplinary research scientists that is required for achieving the intended health benefits. A desk review of personnel database was conducted for information covering 1980-2009 on academic qualifications, training, research experience and research output. The current staff curriculum vitae (CV) were reviewed to gather information on researchers' employment record, training, training support, area of expertise and scientific output. Interviews were conducted with a cross section of researchers on capacity development aspects using a self-administered questionnaire. In-depth interviews were also conducted with the current and former NIMR Management to seek information on capacity development challenges. A review was also done on staff personal files, annual reports, strategic plans and other occasional documents. A total of 163 CV were assessed; of these, 76.7% (125) were for Research Scientists (RS), 20.9% (34) Laboratory Technologists (LT) and 2.4% (4) for System Analysts. The Institute had 13 research scientists upon its establishment. Since 1980, NIMR has recruited a total of 185 Research Scientists. By 2009, NIMR had a total scientific workforce of 170 staff (RS= 82.4%; LT= 17.6%). Of the 140 RSs, 37 (26.4%), were first degree; 77 (55.5%) second degree while 26 (18.6%) were PhD degree holders. Of the total of 78 researchers interviewed, 55 (70.5%) indicated to have accessed postgraduate training through their personal efforts and 23 through institutional arrangement. Sixty (77%) respondents were satisfied with their tenure at NIMR. Seventy (89%) indicated that they had not at any point considered leaving NIMR. Most (79%) research scientists were recruited while holding a first degree, a few (17%) with second degree while only one (0.7%) holding a PhD degree. NIMR has experienced a research scientist attrition rate of 17.5%. Staff retention factors included availability of training opportunities; passion for conducting research; and good career prospects. Despite having a training programme, the institute has never at any moment been able to hold its own training resources. Being a public research institution, NIMR receives its core funding from the government of the United Republic of Tanzania. The bulk of the funding appears to be spent on personnel emoluments that take up to 85% (mean = 66%) of the allocated budget. In conclusion, the current NIMR's research capacity building is dependent mainly on foreign funding and personal initiatives. There is an urgent need to increase local funding for capacity building and conduct of research. A programme should be put in place to ensure sustainability of the capacity building process.

Specific conductance measurements in central and western New York streams - A retrospective characterization

USGS Publications Warehouse

Kappel, William M.; Sinclair, Gaylen J.; Reddy, James E.; Eckhardt, David A.; deVries, M. Peter; Phillips, Margaret E.

2012-01-01

U.S. Geological Survey (USGS) Data Rescue Program funds were used to recover data from paper records for 139 streamgages across central and western New York State; 6,133 different streamflow measurement forms, collected between 1970-80, contained field water-quality measurements. The water-quality data were entered, reviewed, and uploaded into the USGS National Water Information System. In total, 4,285 unique site visits were added to the database. The new values represent baseline water quality from which to measure change and will lead to a comparison of water-quality change over the last 40 years and into the future. Specific conductance was one of the measured properties and represents a simple way to determine if ambient inorganic water quality has been altered by anthropogenic (road salt runoff, wastewater discharges, or natural gas development) or natural sources. The objective of this report is to describe ambient specific conductance characteristics of surface water across the central and western part of New York. This report presents median specific conductance of stream discharge for the period 1970-80 and a description of the relation between specific conductance and concentrations of total dissolved solids (TDS) retrieved from the USGS National Water Information System (NWIS) database from 1955 to present. The data descriptions provide a baseline of surface-water specific conductance data that can used for comparison to current and future measurements in New York streams.

A Study of Information Content in the U.S. Television Commercials: Has It Become Less Informative but More Creative?

ERIC Educational Resources Information Center

Ng, Daniel; Supaporn, Potibut

A study investigated the trend of current U.S. television commercial informativeness by comparing the results with Alan Resnik and Bruce Stern's previous benchmark study conducted in 1977. A systematic random sampling procedure was used to select viewing dates and times of commercials from the three national networks. Ultimately, a total of 550…

An Assessment of the Attitudes of Three Big Football Teams' Supporters in Turkey towards Fanaticism

ERIC Educational Resources Information Center

Tasmektepligil, Mehmet Yalcin

2016-01-01

The purpose of this study is to evaluate the attitudes of the spectators of the three big football teams in Turkey towards being a supporter. The study was conducted on a total of 429 individuals who were members of the supporters unions of Besiktas, Galatasaray and Fenerbahçe teams, current champions of Turkey's Spor Toto Super League, which have…

The Influence of Age, Sex, Social Class and Religion on Television Viewing Time and Programme Preferences among 11-15 Year Olds.

ERIC Educational Resources Information Center

Francis, Leslie J.; Gibson, Harry M.

1993-01-01

Describes a study that was conducted to investigate the influence of age, sex, social class, and religion on total television viewing time and program preferences among a large sample of Scottish secondary school students. Four main program types are examined, i.e., soap, sport, light entertainment, and current awareness. (50 references) (LRW)

Influence of water conductivity on particular electrospray modes with dc corona discharge — optical visualization approach

NASA Astrophysics Data System (ADS)

Pongrác, Branislav; Kim, Hyun-Ha; Negishi, Nobuaki; Machala, Zdenko

2014-08-01

The effect of water conductivity on electrospraying of water was studied in combination with positive DC corona discharge generated in air. We used a point-to-plane geometry of electrodes with a hollow syringe needle anode opposite to the metal mesh cathode. We employed total average current measurements and high-speed camera fast time-resolved imaging. We visualized the formation of a water jet (filament) and investigated corona discharge behavior for various water conductivities. Depending on the conductivity, various jet properties were observed: pointy, prolonged, and fast spreading water filaments for lower conductivity; in contrast to rounder, broader, and shorter quickly disintegrating filaments for higher conductivity. The large acceleration values (4060 m/s2 and 520 m/s2 for 2 μS/cm and 400 μS/cm, respectively) indicate that the process is mainly governed by the electrostatic force. In addition, with increasing conductivity, the breakdown voltage for corona-to-spark transition was decreasing.

Comparison of predictive estimates of high-latitude electrodynamics with observations of global-scale Birkeland currents

NASA Astrophysics Data System (ADS)

Anderson, Brian J.; Korth, Haje; Welling, Daniel T.; Merkin, Viacheslav G.; Wiltberger, Michael J.; Raeder, Joachim; Barnes, Robin J.; Waters, Colin L.; Pulkkinen, Antti A.; Rastaetter, Lutz

2017-02-01

Two of the geomagnetic storms for the Space Weather Prediction Center Geospace Environment Modeling challenge occurred after data were first acquired by the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE). We compare Birkeland currents from AMPERE with predictions from four models for the 4-5 April 2010 and 5-6 August 2011 storms. The four models are the Weimer (2005b) field-aligned current statistical model, the Lyon-Fedder-Mobarry magnetohydrodynamic (MHD) simulation, the Open Global Geospace Circulation Model MHD simulation, and the Space Weather Modeling Framework MHD simulation. The MHD simulations were run as described in Pulkkinen et al. (2013) and the results obtained from the Community Coordinated Modeling Center. The total radial Birkeland current, ITotal, and the distribution of radial current density, Jr, for all models are compared with AMPERE results. While the total currents are well correlated, the quantitative agreement varies considerably. The Jr distributions reveal discrepancies between the models and observations related to the latitude distribution, morphologies, and lack of nightside current systems in the models. The results motivate enhancing the simulations first by increasing the simulation resolution and then by examining the relative merits of implementing more sophisticated ionospheric conductance models, including ionospheric outflows or other omitted physical processes. Some aspects of the system, including substorm timing and location, may remain challenging to simulate, implying a continuing need for real-time specification.

Increased use of antipsychotic long-acting injections with community treatment orders.

PubMed

Patel, Maxine X; Matonhodze, Jane; Baig, Mirza K; Gilleen, James; Boydell, Jane; Holloway, Frank; Taylor, David; Szmukler, George; Lambert, Tim; David, Anthony S

2011-04-01

Community treatment orders (CTOs) are increasingly being used, despite a weak evidence base, and problems continue regarding Second Opinion Appointed Doctor (SOAD) certification of medication. The aim of the current study was to describe current CTO usage regarding patient characteristics, prescribed medication and CTO conditions. A 1-year prospective cohort study with consecutive sampling was conducted for all patients whose CTO was registered in a large mental health trust. Only the first CTO for each patient was included. Measures included sociodemographic variables, psychiatric diagnosis, CTO date of initiation and conditions, psychotropic medication and date of SOAD certification for medication. This study was conducted in the first year of CTO legislation in England and Wales. A total of195 patients were sampled (mean age 40.6 years, 65% male, 52% black ethnic origin). There was significant geographical variability in rates of CTO use (χ(2) = 11.3, p = 0.012). A total of 53% had their place of residence specified as a condition and 29% were required to allow access into their homes. Of those with schizophrenia, 64% were prescribed an antipsychotic long-acting injection (LAI). Of the total group, 7% received high-dose antipsychotics, 10% were prescribed two antipsychotics and only 15% received SOAD certification in time. There was geographical and ethnic variation in CTO use but higher rates of hospital detention in minority ethnic groups may be contributory. Most patients were prescribed antipsychotic LAIs and CTO conditions may not follow the least restrictive principle.

Dissection of K+ currents in Caenorhabditis elegans muscle cells by genetics and RNA interference

PubMed Central

Santi, C. M.; Yuan, A.; Fawcett, G.; Wang, Z.-W.; Butler, A.; Nonet, M. L.; Wei, A.; Rojas, P.; Salkoff, L.

2003-01-01

GFP-promoter experiments have previously shown that at least nine genes encoding potassium channel subunits are expressed in Caenorhabditis elegans muscle. By using genetic, RNA interference, and physiological techniques we revealed the molecular identity of the major components of the outward K+ currents in body wall muscle cells in culture. We found that under physiological conditions, outward current is dominated by the products of only two genes, Shaker (Kv1) and Shal (Kv4), both expressing voltage-dependent potassium channels. Other channels may be held in reserve to respond to particular circumstances. Because GFP-promoter experiments indicated that slo-2 expression is prominent, we created a deletion mutant to identify the SLO-2 current in vivo. In both whole-cell and single-channel modes, in vivo SLO-2 channels were active only when intracellular Ca2+ and Cl- were raised above normal physiological conditions, as occurs during hypoxia. Under such conditions, SLO-2 is the largest outward current, contributing up to 87% of the total current. Other channels are present in muscle, but our results suggest that they are unlikely to contribute a large outward component under physiological conditions. However, they, too, may contribute currents conditional on other factors. Hence, the picture that emerges is of a complex membrane with a small number of household conductances functioning under normal circumstances, but with additional conductances that are activated during unusual circumstances. PMID:14612577

Macroalgae in a spring stream in Shanxi Province: composition and relation to physical and chemical variables

NASA Astrophysics Data System (ADS)

Hu, Bianfang; Xie, Shulian

2007-07-01

Fourteen stream segments were investigated throughout the Xin’an Spring in Shanxi Province, China in 2004. The variation ranges in stream size, current velocity, discharge, dissolved oxygen, and specific conductance were large. Twenty-two macroalgae species were found in the stream. Major divisions in terms of species numbers were Chlorophyta (59.1%), Cyanophyta (22.8%), Xanthophyta (9.1%), Rhodophyta (4.5%) and Charophyta (4.5%). The most widespread species, Cladophora rivularis (50.0%), also Oedogonium sp. (42.9%) and Spirogyra sp. (42.9%) were well represented throughout the stream, whereas another 10 species were found in only one sampling site. Total percentage cover varied from <1% to 90%. Red algae Batrachospermum acuatum and the charophytes Chara vulgaris have the highest percentage cover. Among the parameters analyzed, the stream width, specific conductance and dissolved oxygen were the ones that more closely related to the species number and percentage cover of macroalgal communities. The species number of each site was negatively correlated with dissolved oxygen content. The total percentage cover of the macroalgae was negatively correlated with the stream width and the specific conductance.

Characterization of mixed-conducting barium cerate-based perovskites for potential fuel cell applications

NASA Astrophysics Data System (ADS)

Mukundan, R.

Chemical modifications of barium cerium gadolinium oxide through the substitution of Bi, Tb, Pr, Nb and Ta were attempted in an effort to increase the p-type or n-type conductivity, and to develop new mixed-conducting electrodes that are chemically compatible with the Ba(Cesb{1-x}Gdsb{x})Osb{3-x/2} electrolyte. The structure, oxygen non-stoichiometry, electronic and ionic-conductivity of several compositions in the doped-barium cerate systems were studied by X-ray diffraction, TGA, DC and AC conductivity, and EMF measurements. The cathodic overpotential of the mixed (electronic/ionic) conducting compositions in this system, on a Ba(Cesb{0.8}Gdsb{0.2})Osb{2.9} electrolyte, were also studied using Current Interruption and AC impedance techniques. The substitution of Bi into Ba(Cesb{0.9}Gdsb{0.1})Osb{2.95} lead to a significant increase in the electronic conductivity, and a total conductivity of about 0.94 S/cm was obtained for Ba(Bisb{0.5}Cesb{0.4}Gdsb{0.1})Osb3 at 800sp°C in air. However, the concentration of oxygen-ion vacancies and hence the ionic conductivity decreased due to the oxidation of Bi to the 5sp{+} state. Compositions in the Ba(Bisb{0.5}Cesb{x}Gdsb{0.5-x})Osb3 system also exhibited significant oxygen non-stoichiometry depending upon the ordering of the B-site cations and the relative concentrations of Ce and Gd. However, the absence of any detectable EMF in the non-stoichiometric compositions implied that the oxygen vacancies are strongly associated with the Bisp{3+} cations. Although highly conductive, chemically stable compositions were prepared in the Ba(Bisb{x}Cesb{y}Gdsb{1-(x+y)})Osb{3-d} system, their ionic conductivities were low. The mixed-conduction properties of Ba(Cesb{1-x}Gdsb{x})Osb{3-d} were enhanced under cathode conditions (600-800sp°C in air) by the substitution of Ce by Tb and Pr. While the substitution of Tb resulted in a decrease in the total conductivity, Pr induced a significant increase in the total conductivity at high Pr levels (≥40 mole%) due to an enhancement of the electronic conductivity. The Ba(Prsb{0.8}Gdsb{0.2})Osb{2.9} sample was found to have the best mixed-conducting properties of all the perovskites evaluated, sigmasb{T}=0.75 S/cm in air at 800sp°C, tsb{H+}=0.15 in a wet argon//dry argon gradient, and tsb{0.2-}≈ 0.05 in a dry air//dry argon gradient. The cathodic overpotentials of the mixed-conducting Pr-doped barium cerates were low, and decreased with increasing ionic and electronic conductivity of the electrode. The lowest overpotential was obtained for the Ba(Prsb{0.8}Gdsb{0.2})Osb{2.9}, cathode, and at low current densities was comparable to that of an optimized porous Pt-electrode. While the substitution of Nb and Ta for Ce lead to an enhancement in the electronic conductivity under reducing conditions associated with the increased reduction of Cesp{4+} to Cesp{3+}, the ionic-conductivity of these perovskites was low. There was no evidence for any protonic conductivity in the 15 mole% Nb and Ta substituted barium cerates. Moreover the anodic overpotential and the anode resistance of these perovskites on a Ba(Cesb{0.8}Gdsb{0.2})Osb{2.9} electrolyte were both high.

5 MeV Proton irradiation effects on 200 GHz silicon-germanium heterojunction bipolar transistors

NASA Astrophysics Data System (ADS)

Gnana Prakash, A. P.; Hegde, Vinayakprasanna N.; Pradeep, T. M.; Pushpa, N.; Bajpai, P. K.; Patel, S. P.; Trivedi, Tarkeshwar; Cressler, J. D.

2017-12-01

The total dose effects of 5 MeV proton and Co-60 gamma irradiation in the dose range from 1 to 100 Mrad on advanced 200 GHz Silicon-Germanium heterojunction bipolar transistors (SiGe HBTs) are investigated. The SRIM simulation study was conducted to understand the energy loss of 5 MeV proton ions in SiGe HBT structure. Pre- and post-radiation DC figure of merits such as forward- and inverse-mode Gummel characteristics, excess base current, DC current gain and output characteristics were used to quantify the radiation tolerance of the devices. The results show that the proton creates a significant amount of damages in the surface and bulk of the transistor when compared with gamma irradiation. The SiGe HBTs shows robust ionizing radiation tolerance even up to a total dose of 100 Mrad for both radiations.

Cholinergically-induced changes in outward currents in hair cells isolated from the semicircular canal of the frog.

PubMed

Housley, G D; Norris, C H; Guth, P S

1990-01-01

Two cholinergically-induced modulations of membrane conductances have been identified in hair cells isolated from the crista ampullaris of the leopard frog (Rana pipiens), using the whole cell recording configuration of the patch clamp technique. Of 56 crista hair cells tested, 28 showed drug-induced changes in membrane current or membrane potential which were repeatable and could be reversed with washout of drug. The predominant effect (observed in 20 hair cells) of acetylcholine (Ach, 100 microM) to 1mM) or carbachol (1 microM to 50 microM) applied to these hair cells was the reduction of an outward current corresponding to a change in conductance of approximately -0.22 nS. This action by Ach on hair cells has been inferred from previous studies of afferent fiber discharge which reported an increase in firing rate with stimulation of efferent fibers or exogenous application of cholinomimetics (Bernard et al., 1985; Valli et al., 1986; Guth et al., 1986; Norris et al., 1988a). The Ach-induced reduction in outward current was associated with a depolarization of the zero-current membrane potential by approximately +2.5 mV. In a total of 8 hair cells, an Ach-induced reversible increase in outward current was recorded. Changes in conductance were approximately +0.13 nS and were associated with a hyperpolarization of the zero-current membrane potential by approximately -2.2 mV. This current increase is likely to be responsible for the inhibitory post-synaptic potentials (IPSPs) which have previously been recorded intracellularly from acoustico-lateralis hair cells during stimulation of the efferent innervation (Flock and Russell, 1976; Ashmore and Russell, 1982; Art et al., 1984, 1985). Of the remaining 28 hair cells, six cells failed to exhibit any change in membrane conductance or membrane potential in the presence of cholinomimetics while an additional 15 cells exhibited decreases, and 7 cells exhibited increases in outward conductance, during application of Ach or carbachol, which were neither reversible with washout nor repeatable. The Ach-induced decrease in outward current could be reversible blocked by removal of Ca2+ from the external solution. The antagonism of the Ach-induced decrease in outward current by atropine (10(-5) M) suggests that this current may correspond to a facilitatory, 'atropine-preferring' Ach receptor mediated response previously identified in the isolated semicircular canal (Norris et al., 1988a).(ABSTRACT TRUNCATED AT 400 WORDS)

Electrical transport properties of thermally evaporated phthalocyanine (H 2Pc) thin films

NASA Astrophysics Data System (ADS)

El-Nahass, M. M.; Farid, A. M.; Attia, A. A.; Ali, H. A. M.

2006-08-01

Thin films of H 2Pc of various thicknesses have been deposited onto glass substrates using thermal evaporation technique at room temperature. The dark electrical resistivity measurements were carried out at different temperatures in the range 298-473 K. An estimation of mean free path ( lo) of charge carriers in H 2Pc thin films was attempted. Measurements of thermoelectric power confirm that H 2Pc thin films behave as a p-type semiconductor. The current density-voltage characteristics of Au/H 2Pc/Au at room temperature showed ohmic conduction mechanism at low voltages. At higher voltages the space-charge-limited conduction (SCLC) accompanied by an exponential trap distribution was dominant. The temperature dependence of current density allows the determination of some essential parameters such as the hole mobility ( μh), the total trap concentration ( Nt), the characteristic temperature ( Tt) and the trap density P( E).

A Literature Review of Health Risks in the Bear Community, a Gay Subculture

PubMed Central

Quidley-Rodriguez, Narciso; De Santis, Joseph P.

2015-01-01

Gay men’s subcultural identifications may help explain why certain groups of gay men are more at risk than other groups. One such subculture is the Bear community, a group that espouses that large-framed, hirsute men are attractive. To understand current health risks among the Bear community, a literature search was conducted using Medline, Psychinfo, CINAHL, and LGBT Life. A total of eight articles were found addressing health risks in the Bear community. There is a dearth of literature that focuses on the Bear community, but the current literature indicates that Bears are more likely to have a higher body mass index, lower self-esteem, and engage in risky sexual behaviors than other gay men. Suggestions for engaging and conducting research with the Bear community are provided. Last, clinical implications offer guidance for health care providers working with the Bear community to ensure that appropriate care is delivered to these men. PMID:26718773

Large-scale disruptions in a current-carrying magnetofluid

NASA Technical Reports Server (NTRS)

Dahlburg, J. P.; Montgomery, D.; Doolen, G. D.; Matthaeus, W. H.

1986-01-01

Internal disruptions in a strongly magnetized electrically conducting fluid contained within a rigid conducting cylinder of square cross section are investigated theoretically, both with and without an externally applied axial electric field, by means of computer simulations using the pseudospectral three-dimensional Strauss-equations code of Dahlburg et al. (1985). Results from undriven inviscid, driven inviscid, and driven viscid simulations are presented graphically, and the significant effects of low-order truncations on the modeling accuracy are considered. A helical current filament about the cylinder axis is observed. The ratio of turbulent kinetic energy to total poloidal magnetic energy is found to undergo cyclic bounces in the undriven inviscid case, to exhibit one large bounce followed by decay to a quasi-steady state with poloidal fluid velocity flow in the driven inviscid case, and to show one large bounce followed by further sawtoothlike bounces in the driven viscid case.

A phenomenological model of solar flares

NASA Technical Reports Server (NTRS)

Colgate, S. A.

1978-01-01

The energy of solar flares is derived from the magnetic energy of fields convected to the sun's surface and subsequently converted to heat and energetic particles within the chromosphere. The circumstances of this conversion in most current models is magnetic flux annihilation at a neutral sheet. An analysis is conducted of the constraints of flux annihilation. It is shown that the present evidence of solar cosmic rays, X-rays, gamma-rays, and total energy suggests a choice of annihilation not at a neutral point, but by an enhanced dissipation of a field-aligned current. The field configuration is related both to its origin and to the extensive theory and laboratory experiments concerned with this configuration in magnetic fusion. The magnetic field model is applied to the August 4 flare. It is shown how the plasma heating in the annihilation region balanced by thermal conduction leads to a plasma temperature of about 20 million deg K.

Family income per capita, age, and smoking status are predictors of low fiber intake in residents of São Paulo, Brazil.

PubMed

Santos, Paula Victória Félix Dos; Sales, Cristiane Hermes; Vieira, Diva Aliete Santos; de Mello Fontanelli, Mariane; Marchioni, Dirce Maria; Fisberg, Regina Mara

2016-05-01

We hypothesized that dietary total fiber intake may be less than recommendations and that the intake of total, soluble, and insoluble fiber may be associated with demographic, lifestyle, and socioeconomic factors. Data were drawn from the Health Survey of São Paulo, a cross-sectional population-based study. Adolescents, adults, and elderly persons living in São Paulo city were included. Demographic, lifestyle, and anthropometric data were collected from households. Dietary intake was measured using two 24-hour dietary recalls. All analyses were conducted based on the sample design of the study. The proportion of individuals who met the adequate intake (AI) for total fiber intake was examined, and foods that contributed to the intake of fiber and fractions were evaluated. The relationship of total, soluble, and insoluble fiber intake with demographic, socioeconomic, and lifestyle characteristics was determined using multiple linear regression models. A low proportion of individuals met the AI for dietary fiber. The foods that most contributed to total fiber intake were beans, French bread, and rice. Total fiber intake was negatively associated with former and current smokers and positively associated with family income per capita and age. Soluble fiber intake was negatively associated with current smokers and positively associated with female sex, age, and family income per capita. Insoluble fiber intake was negatively associated with former or current smokers and positively associated with age. In summary, residents in the city of São Paulo had a low fiber intake, and demographic, socioeconomic, and lifestyle factors were associated with dietary fiber and intake of its fractions. Copyright © 2016 Elsevier Inc. All rights reserved.

Vertebrate rod photoreceptors express both BK and IK calcium-activated potassium channels, but only BK channels are involved in receptor potential regulation.

PubMed

Pelucchi, Bruna; Grimaldi, Annalisa; Moriondo, Andrea

2008-01-01

In salamander rods, Ca(2+)-activated K(+) current (I(KCa)) provides an effective "clamp" of the dark membrane potential to its normal resting level. By a combination of electrophysiological, pharmacological, and immunohistochemical approaches, we show that salamander rods functionally express large-conductance Ca(2+)- and voltage-dependent potassium (BK) channel and intermediate-conductance Ca(2+)-dependent potassium (IK) channel, but not small-conductance Ca(2+)-dependent potassium channel (SK) subtypes. Application of 100 nM iberiotoxin and 100 nM clotrimazole reduced net I(KCa) to 36% and 63%, respectively, whereas the current was unaffected by application of 1 microM apamin. Consistently, anti- SK1, -SK2, and -SK3 antibodies were unable to stain rod photoreceptors, whereas both anti-BK and -SK4/ IK1 antibodies heavily stained the ellipsoid region of the inner segments of the rods. Moreover, by using current-clamp experiments, it was clearly seen that the strong clamping effect of the total I(KCa) was lost when IbTx, but not CLTZ, was applied to the bath. This behavior strongly suggests that of BK and IK channels, only the former are responsible for the clamping effect on the photoreceptor membrane potential.

Changes of hydrogen peroxide and radical-scavenging activity of raspberry during osmotic, convective, and freeze-drying.

PubMed

Novaković, Miroslav M; Stevanović, Snežana M; Gorjanović, Stanislava Ž; Jovanovic, Predrag M; Tešević, Vele V; Janković, Miodrag A; Sužnjević, Desanka Ž

2011-05-01

This study was conducted to investigate the influence of different drying treatments on antioxidant (AO) activity and phenolic content of raspberry (Rubus idaeus), cultivar Willamette. Whole raspberry fruits were dried convectively (air-drying), osmotically, and freeze-dried. Acetone-water extracts of fresh and dried raspberries were assessed for total phenolic content by standard Folin-Ciocalteau method. Two AO assays were applied, a recently developed direct current (DC) polarographic assay based on decrease of anodic oxidation current of hydrogen peroxide and widely used radical scavenge against the 1,1-diphenyl-2-picrylhydrazyl (DPPH). Strong correlation has been obtained between both AO assays and total phenolic content. In addition, some individual phenolic compounds present in raspberry have been assessed using DPPH and DC polarographic assay. Comparison and evaluation of drying methods has been based on preservation of AO activity and total phenolic content. Obtained results confirmed superiority of freeze-drying; convective drying caused slight changes while osmotic dehydration showed a significant decrease of phenolic compounds and AO activity. © 2011 Institute of Food Technologists®

An Intrinsic Fiber-Optic Sensor for Structure Lightning Current Measurement

NASA Technical Reports Server (NTRS)

Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.; Mata, Carlos T.; Mata, Angel. G.; Snyder, Gary P.

2014-01-01

An intrinsic optical-fiber sensor based on Faraday Effect is developed that is highly suitable for measuring lightning current on aircraft, towers and complex structures. Originally developed specifically for aircraft installations, it is light-weight, non-conducting, structure conforming, and is immune to electromagnetic interference, hysteresis and saturation. It can measure total current down to DC. When used on lightning towers, the sensor can help validate other sensors and lightning detection network measurements. Faraday Effect causes light polarization to rotate when the fiber is exposed to a magnetic field in the direction of light propagation. Thus, the magnetic field strength can be determined from the light polarization change. By forming closed fiber loops and applying Ampere's law, measuring the total light rotation yields the total current enclosed. A broadband, dual-detector, reflective polarimetric scheme allows measurement of both DC component and AC waveforms with a 60 dB dynamic range. Two systems were built that are similar in design but with slightly different sensitivities. The 1310nm laser system can measure 300 A - 300 kA, and has a 15m long sensing fiber. It was used in laboratory testing, including measuring current on an aluminum structure simulating an aircraft fuselage or a lightning tower. High current capabilities were demonstrated up to 200 kA at a lightning test facility. The 1550nm laser system can measure 400 A - 400 kA and has a 25m fiber length. Used in field measurements, excellent results were achieved in the summer of 2012 measuring rocket-triggered lightning at the International Center for Lightning Research and Testing (ICLRT), Camp Blanding, Florida. In both systems increased sensitivity can be achieved with multiple fiber loops. The fiber optic sensor provides many unique capabilities not currently possible with traditional sensors. It represents an important new tool for lightning current measurement where low weight, complex shapes, large structure dimension, large current, and low frequency capabilities are important considerations.

Mediating Role of Psychological Resources on the Association Between Childhood Socioeconomic Status and Current Health in the Community Adult Population of Japan.

PubMed

Kan, Chiemi; Kawakami, Norito; Umeda, Maki

2015-12-01

The majority of studies on the role of psychological resources linking childhood socioeconomic status (SES) and adult health have been conducted in Western countries. Empirical evidence for mediation effects of psychological resources is currently lacking in Japan. The purpose of this study was to investigate the mediating effect of psychological resources (mastery and sense of coherence [SOC]) on the association between childhood SES and current health. Analyses were conducted on cross-sectional data (1,497 men and 1,764 women) from the Japanese Study of Stratification, Health, Income, and Neighborhood Study (J-SHINE) in Tokyo. Psychological resources (mastery and SOC), childhood SES (parents' education and perceived childhood SES), and current health of adults (psychological distress measured by K6 and self-rated health) were measured using a self-report questionnaire. Mastery and SOC significantly and independently mediated the association between childhood SES and current health in the total sample after adjusting for age, gender, and respondent education, regardless of type of SES or health outcome indicators. Similar mediation effects were observed for both men and women. A few gender differences were observed; specifically, SOC significantly mediated the association between parents' education and current health only among women, and it mediated the association between perceived childhood SES and current health only among men. Overall, the findings underscore the importance of the mediating role of psychological resources in the association between childhood SES and current health.

Current understanding of chronic total occlusion of the internal carotid artery

PubMed Central

Xu, Baofeng; Li, Chao; Guo, Yunbao; Xu, Kan; Yang, Yi; Yu, Jinlu

2018-01-01

At present, there is limited understanding of chronic total occlusion (CTO) of the internal carotid artery (ICA). Therefore, the present report collected related cases from PubMed and reviewed the literature. Cerebral vessels may form collateral circulation immediately or gradually following CTO of the ICA. The natural history of CTO of the ICA includes a variety of outcomes, all of which are biased toward a non-benign progressive process and are characterized by insufficient cerebral perfusion, embolus detachment and cognitive dysfunction. The majority of cases of CTO of the ICA require treatment. In early studies, the results of external-ICA bypass were unsatisfactory, while recanalization is now considered the only viable option. The current treatment indications mainly depend on the degree of injury to the cerebrovascular reserve and the extent to which the oxygen extraction fraction is increased. The length, height and duration of ICA occlusion are also relevant, though more frequently, the condition depends on multiple factors. Endovascular interventional recanalization, carotid endarterectomy (CEA) and hybrid surgery may be conducted in a select group of patients. As novel materials are developed, the success rate of simple recanalization may gradually increase; however, hybrid surgery may be more representative of the current trend, as advanced CEA can remove carotid atherosclerosis plaques, thus reducing the technological demands of the subsequent interventional recanalization. There are many complications that may result from recanalization following CTO of the ICA, including hyperperfusion and technical errors; therefore, the operation must be conducted carefully. If the recanalization is successful, it typically results in a stable improvement of patient condition in the long term. However, despite these conclusions, more studies are required in the future to further improve current understanding of CTO of the ICA. PMID:29435269

A Study to Document the Effects of Altering Traditional Dental School Recruitment and Admissions Policies for Minority Students. Volume IV: Appendices.

ERIC Educational Resources Information Center

Kell, Diane; And Others

A total of 84 citations is included in this bibliography. In addition, about one third of the articles have been abstracted; the rest are reviewed but not summarized. In general, the abstracted articles are judged to be the most useful in the conduct of this particular study, which evaluates the current position of minority students in dental…

Factors Influence the Digital Media Teaching of Primary School Teachers in a Flipped Class: A Taiwan Case Study

ERIC Educational Resources Information Center

Cheng, Yung-Hsun; Weng, Chia-Wen

2017-01-01

The current study focuses on the key roles that affect the success of a flipped classroom. The research was conducted with a questionnaire survey created from a study of literature review. Out of a total of 441 samples, 424 valid samples (96.14%) from teachers have been received. The study key conclusions are as follows: (1) a principal leadership…

Status of bottomland forests in the Albemarle Sound of North Carolina and Virginia, 1984-2012

Treesearch

Jean H. Lorber; Anita K. Rose

2015-01-01

The Albemarle Sound, a 6-million-acre watershed, contains some of the largest areas of bottomland hardwood habitat in the Eastern United States. Using close to 30 years of data from the Forest Inventory and Analysis Program, a study of the current status and trends in the Albemarle Sound’s bottomland forest system was conducted. In 2012, bottomlands totaled...

The Effect of Talking Drawings on Five-Year-Old Turkish Children's Mental Models of the Water Cycle

ERIC Educational Resources Information Center

Ahi, Berat

2017-01-01

The purpose of the current study is to determine the effect of talking drawings on Turkish preschool children's mental models of the water cycle. The study was conducted in the city of Kastamonu, located in the north-west of Turkey. A total of 40 five-year-old preschool children participated in the study in the spring term of the 2015-2016 school…

Japanese MAGSAT Team

NASA Technical Reports Server (NTRS)

Fukushima, N. (Principal Investigator)

1982-01-01

CHRONINT and investigator B tapes as well as CHRONFIN data are being analyzed using a graphical display to illustrate X.Y,Z components as well as their residuals from the MGST (4/81) model. In addition to surveys of the vicinity of Japan, an aerial magnetic survey was conducted around Syowa Station in the Antarctic. Relative data collected by polar orbiting satellites are also being studied. Techniques used to separate external and internal fields from the vector data along the orbital paths; analysis of the frequency of the toroidal current in the equatorial ionosphere; investigation of the sudden storm commencement observed by MAGSAT; determination of the structure of field aligned currents associated with substorms; and calculation of the total electric current passing through the plane encircled by the MAGSAT orbit are discussed.

Improvement of the grid-connect current quality using novel proportional-integral controller for photovoltaic inverters.

PubMed

Cheng, Yuhua; Chen, Kai; Bai, Libing; Yang, Jing

2014-02-01

Precise control of the grid-connected current is a challenge in photovoltaic inverter research. Traditional Proportional-Integral (PI) control technology cannot eliminate steady-state error when tracking the sinusoidal signal from the grid, which results in a very high total harmonic distortion in the grid-connected current. A novel PI controller has been developed in this paper, in which the sinusoidal wave is discretized into an N-step input signal that is decided by the control frequency to eliminate the steady state error of the system. The effect of periodical error caused by the dead zone of the power switch and conduction voltage drop can be avoided; the current tracking accuracy and current harmonic content can also be improved. Based on the proposed PI controller, a 700 W photovoltaic grid-connected inverter is developed and validated. The improvement has been demonstrated through experimental results.

A Fiber-Optic Current Sensor for Lightning Measurement Applications

NASA Technical Reports Server (NTRS)

Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.

2015-01-01

An optical-fiber sensor based on Faraday Effect is developed for measuring total lightning electric current. It has many unique capabilities not possible with traditional current sensors. Designed for aircraft installation, the sensor is lightweight, non-conducting, structure-conforming, and is immune to electromagnetic interference, hysteresis and saturation. It can also be used on windmills, lightning towers, and can help validate lightning detection network measurements. Faraday Effect causes light polarization to rotate when the fiber is exposed to a magnetic field in the direction of light propagation. Thus, the magnetic field strength can be determined from the light polarization change. By forming closed fiber loops and applying Ampere's law, measuring the total light rotation yields the total current enclosed. The broadband, dual-detector, reflective polarimetric scheme allows measurement of both DC component and AC waveforms with about 60 dB dynamic range. Three sensor systems were built with different sensitivities from different laser wavelengths. Operating at 850nm, the first system uses twisted single-mode fiber and has a 150 A - 150 KA range. The second system operates at 1550nm, uses spun polarization maintaining fiber, and can measure 400 A - 400 KA. Both systems were validated with rocket-triggered lightning measurements and achieved excellent results when compared to a resistive shunt. The third system operates at 1310nm, uses spun polarization maintaining fiber, and can measure approximately 300 A - 300 KA. High current measurements up to 200 KA were demonstrated at a commercial lightning test facility. The system was recently installed on an aircraft and flown near icing weather conditions.

A fiber-optic current sensor for lightning measurement applications

NASA Astrophysics Data System (ADS)

Nguyen, Truong X.; Ely, Jay J.; Szatkowski, George N.

2015-05-01

An optical-fiber sensor based on Faraday Effect is developed for measuring total lightning electric current. It has many unique capabilities not possible with traditional current sensors. Designed for aircraft installation, the sensor is lightweight, non-conducting, structure-conforming, and is immune to electromagnetic interference, hysteresis and saturation. It can also be used on windmills, lightning towers, and can help validate lightning detection network measurements. Faraday Effect causes light polarization to rotate when the fiber is exposed to a magnetic field in the direction of light propagation. Thus, the magnetic field strength can be determined from the light polarization change. By forming closed fiber loops and applying Ampere's law, measuring the total light rotation yields the total current enclosed. The broadband, dual-detector, reflective polarimetric scheme allows measurement of both DC component and AC waveforms with about 60 dB dynamic range. Three sensor systems were built with different sensitivities from different laser wavelengths. Operating at 850nm, the first system uses twisted single-mode fiber and has a 150 A - 150 KA range. The second system operates at 1550nm, uses spun polarization maintaining fiber, and can measure 400 A - 400 KA. Both systems were validated with rocket-triggered lightning measurements and achieved excellent results when compared to a resistive shunt. The third system operates at 1310nm, uses spun polarization maintaining fiber, and can measure approximately 300 A - 300 KA. High current measurements up to 200 KA were demonstrated at a commercial lightning test facility. The system was recently installed on an aircraft and flown near icing weather conditions.

Development of HEATHER for cochlear implant stimulation using a new modeling workflow.

PubMed

Tran, Phillip; Sue, Andrian; Wong, Paul; Li, Qing; Carter, Paul

2015-02-01

The current conduction pathways resulting from monopolar stimulation of the cochlear implant were studied by developing a human electroanatomical total head reconstruction (namely, HEATHER). HEATHER was created from serially sectioned images of the female Visible Human Project dataset to encompass a total of 12 different tissues, and included computer-aided design geometries of the cochlear implant. Since existing methods were unable to generate the required complexity for HEATHER, a new modeling workflow was proposed. The results of the finite-element analysis agree with the literature, showing that the injected current exits the cochlea via the modiolus (14%), the basal end of the cochlea (22%), and through the cochlear walls (64%). It was also found that, once leaving the cochlea, the current travels to the implant body via the cranial cavity or scalp. The modeling workflow proved to be robust and flexible, allowing for meshes to be generated with substantial user control. Furthermore, the workflow could easily be employed to create realistic anatomical models of the human head for different bioelectric applications, such as deep brain stimulation, electroencephalography, and other biophysical phenomena.

The effect of inertia on the Dirac electron, the spin Hall current and the momentum space Berry curvature

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

Chowdhury, Debashree, E-mail: debashreephys@gmail.com; Basu, B., E-mail: sribbasu@gmail.com

2013-02-15

We have studied the spin dependent force and the associated momentum space Berry curvature in an accelerating system. The results are derived by taking into consideration the non-relativistic limit of a generally covariant Dirac equation with an electromagnetic field present, where the methodology of the Foldy-Wouthuysen transformation is applied to achieve the non-relativistic limit. Spin currents appear due to the combined action of the external electric field, the crystal field and the induced inertial electric field via the total effective spin-orbit interaction. In an accelerating frame, the crucial role of momentum space Berry curvature in the spin dynamics has alsomore » been addressed from the perspective of spin Hall conductivity. For time dependent acceleration, the expression for the spin polarization has been derived. - Highlights: Black-Right-Pointing-Pointer We study the effect of acceleration on the Dirac electron in the presence of an electromagnetic field, where the acceleration induces an electric field. Black-Right-Pointing-Pointer Spin currents appear due to the total effective electric field via the total spin-orbit interaction. Black-Right-Pointing-Pointer We derive the expression for the spin dependent force and the spin Hall current, which is zero for a particular acceleration. Black-Right-Pointing-Pointer The role of the momentum space Berry curvature in an accelerating system is discussed. Black-Right-Pointing-Pointer An expression for the spin polarization for time dependent acceleration is derived.« less

Pacemaker Dependency after Cardiac Surgery: A Systematic Review of Current Evidence.

PubMed

Steyers, Curtis M; Khera, Rohan; Bhave, Prashant

2015-01-01

Severe postoperative conduction disturbances requiring permanent pacemaker implantation frequently occur following cardiac surgery. Little is known about the long-term pacing requirements and risk factors for pacemaker dependency in this population. We performed a systematic review of the literature addressing rates and predictors of pacemaker dependency in patients requiring permanent pacemaker implantation after cardiac surgery. Using a comprehensive search of the Medline, Web of Science and EMBASE databases, studies were selected for review based on predetermined inclusion and exclusion criteria. A total of 8 studies addressing the endpoint of pacemaker-dependency were identified, while 3 studies were found that addressed the recovery of atrioventricular (AV) conduction endpoint. There were 10 unique studies with a total of 780 patients. Mean follow-up ranged from 6-72 months. Pacemaker dependency rates ranged from 32%-91% and recovery of AV conduction ranged from 16%-42%. There was significant heterogeneity with respect to the definition of pacemaker dependency. Several patient and procedure-specific variables were found to be independently associated with pacemaker dependency, but these were not consistent between studies. Pacemaker dependency following cardiac surgery occurs with variable frequency. While individual studies have identified various perioperative risk factors for pacemaker dependency and non-resolution of AV conduction disease, results have been inconsistent. Well-conducted studies using a uniform definition of pacemaker dependency might identify patients who will benefit most from early permanent pacemaker implantation after cardiac surgery.

Meta-metallic coils and resonators: Methods for high Q-value resonant geometries

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

Mett, R. R.; Department of Physics and Chemistry, Milwaukee School of Engineering, Milwaukee, Wisconsin 53202; Sidabras, J. W.

A novel method of decreasing ohmic losses and increasing Q-value in metallic resonators at high frequencies is presented. The method overcomes the skin-depth limitation of rf current flow cross section. The method uses layers of conductive foil of thickness less than a skin depth and capacitive gaps between layers. The capacitive gaps can substantially equalize the rf current flowing in each layer, resulting in a total cross-sectional dimension for rf current flow many times larger than a skin depth. Analytic theory and finite-element simulations indicate that, for a variety of structures, the Q-value enhancement over a single thick conductor approachesmore » the ratio of total conductor thickness to skin depth if the total number of layers is greater than one-third the square of the ratio of total conductor thickness to skin depth. The layer number requirement is due to counter-currents in each foil layer caused by the surrounding rf magnetic fields. We call structures that exhibit this type of Q-enhancement “meta-metallic.” In addition, end effects due to rf magnetic fields wrapping around the ends of the foils can substantially reduce the Q-value for some classes of structures. Foil structures with Q-values that are substantially influenced by such end effects are discussed as are five classes of structures that are not. We focus particularly on 400 MHz, which is the resonant frequency of protons at 9.4 T. Simulations at 400 MHz are shown with comparison to measurements on fabricated structures. The methods and geometries described here are general for magnetic resonance and can be used at frequencies much higher than 400 MHz.« less

Meta-metallic coils and resonators: Methods for high Q-value resonant geometries

PubMed Central

Mett, R. R.; Hyde, J. S.

2016-01-01

A novel method of decreasing ohmic losses and increasing Q-value in metallic resonators at high frequencies is presented. The method overcomes the skin-depth limitation of rf current flow cross section. The method uses layers of conductive foil of thickness less than a skin depth and capacitive gaps between layers. The capacitive gaps can substantially equalize the rf current flowing in each layer, resulting in a total cross-sectional dimension for rf current flow many times larger than a skin depth. Analytic theory and finite-element simulations indicate that, for a variety of structures, the Q-value enhancement over a single thick conductor approaches the ratio of total conductor thickness to skin depth if the total number of layers is greater than one-third the square of the ratio of total conductor thickness to skin depth. The layer number requirement is due to counter-currents in each foil layer caused by the surrounding rf magnetic fields. We call structures that exhibit this type of Q-enhancement “meta-metallic.” In addition, end effects due to rf magnetic fields wrapping around the ends of the foils can substantially reduce the Q-value for some classes of structures. Foil structures with Q-values that are substantially influenced by such end effects are discussed as are five classes of structures that are not. We focus particularly on 400 MHz, which is the resonant frequency of protons at 9.4 T. Simulations at 400 MHz are shown with comparison to measurements on fabricated structures. The methods and geometries described here are general for magnetic resonance and can be used at frequencies much higher than 400 MHz. PMID:27587143

19. Randomized Controlled Trial of a Neurosteroid Intervention in Schizophrenia

PubMed Central

Marx, Chris; Naylor, Jennifer; Kilts, Jason; Allan, Trina; Smith, Karen; Szabo, Steven; Wagner, Ryan; Buchanan, Robert; Keefe, Richard; Shampine, Lawrence

2017-01-01

Abstract Background: Neurosteroids are endogenous molecules synthesized de novo in brain, adrenals, and other tissues. They demonstrate pleiotropic actions that are highly relevant to the neurobiology of schizophrenia. Clozapine markedly elevates neurosteroids in rodent hippocampus, potentially contributing to its superior therapeutic efficacy. Clinical evidence from a randomized controlled trial (RCT) conducted in Singapore suggests that pregnenolone significantly enhances functional capacity (as demonstrated by improvements in the UPSA Total Score and UPSA Communication Subscale Score) and that neurosteroid changes posttreatment predict therapeutic response (Marx et al 2014; Psychopharmacology). We thus conducted an RCT investigating adjunctive pregnenolone in schizophrenia. Methods: After a 2-week placebo lead-in, 88 participants with schizophrenia were randomized to pregnenolone (n = 42) or placebo (n = 46) for 8 weeks. Neurosteroids were quantified at baseline and posttreatment by mass spectrometry. Functional end points included the UPSA Total Score and UPSA Communication Subscale. Cognitive end points included the MCCB Composite Score and MCCB Subscales. Modified intent-to-treat analyses were conducted. Results: Participants randomized to the pregnenolone group did not outperform placebo on the UPSA Total Score or MCCB Composite Score. However, the pregnenolone group demonstrated significantly greater improvement in the UPSA Communication Subscale compared to participants randomized to placebo (P = .034), replicating prior RCT findings from Singapore. Elevations in pregnenolone post-treatment also predicted improvements in UPSA Total Score (r = .373; P = .039), again replicating prior efforts. In addition, the pregnenolone group demonstrated significantly greater improvement in the MCCB Verbal Learning Subscale compared to placebo (P = .023). Pregnenolone did not outperform placebo in the BACS Composite Score, SANS Total Score, or PANSS Total Score. Pregnenolone was well tolerated. Conclusion: Treatment with pregnenolone appears to improve functional capacity in a US population with schizophrenia, as assessed by the UPSA Communication Subscale and also supported by a significant positive correlation between pregnenolone changes and UPSA Total Score improvements—thus replicating findings from a prior RCT conducted in Singapore. Pregnenolone may also improve verbal memory. Given the positive correlation between pregnenolone increases posttreatment and UPSA Total Score improvements, it is possible that higher doses of pregnenolone may be clinically efficacious, and that neurosteroid quantification has biomarker potential for the predication of therapeutic response. Additional dose-finding investigations will be required to test these hypotheses. A pregnenolone decanoate formulation is currently in preclinical development.

Electrochemical Approach for Analyzing Electrolyte Transport Properties and Their Effect on Protonic Ceramic Fuel Cell Performance.

PubMed

Danilov, Nikolay; Lyagaeva, Julia; Vdovin, Gennady; Medvedev, Dmitry; Demin, Anatoly; Tsiakaras, Panagiotis

2017-08-16

The design and development of highly conductive materials with wide electrolytic domain boundaries are among the most promising means of enabling solid oxide fuel cells (SOFCs) to demonstrate outstanding performance across low- and intermediate-temperature ranges. While reducing the thickness of the electrolyte is an extensively studied means for diminishing the total resistance of SOFCs, approaches involving an improvement in the transport behavior of the electrolyte membranes have been less-investigated. In the present work, a strategy for analyzing the electrolyte properties and their effect on SOFC output characteristics is proposed. To this purpose, a SOFC based on a recently developed BaCe 0.5 Zr 0.3 Dy 0.2 O 3-δ proton-conducting ceramic material was fabricated and tested. The basis of the strategy consists of the use of traditional SOFC testing techniques combined with the current interruption method and electromotive force measurements with a modified polarization-correction assessment. This allows one to determine simultaneously such important parameters as maximal power density; ohmic and polarization resistances; average ion transport numbers; and total, ionic, and electronic film conductivities and their activation energies. The proposed experimental procedure is expected to expand both fundamental and applied basics that could be further adopted to improve the technology of electrochemical devices based on proton-conducting electrolytes.

Currents between tethered electrodes in a magnetized laboratory plasma

NASA Technical Reports Server (NTRS)

Stenzel, R. L.; Urrutia, J. M.

1989-01-01

Laboratory experiments on important plasma physics issues of electrodynamic tethers were performed. These included current propagation, formation of wave wings, limits of current collection, nonlinear effects and instabilities, charging phenomena, and characteristics of transmission lines in plasmas. The experiments were conducted in a large afterglow plasma. The current system was established with a small electron-emitting hot cathode tethered to an electron-collecting anode, both movable across the magnetic field and energized by potential difference up to V approx.=100 T(sub e). The total current density in space and time was obtained from complete measurements of the perturbed magnetic field. The fast spacecraft motion was reproduced in the laboratory by moving the tethered electrodes in small increments, applying delayed current pulses, and reconstructing the net field by a linear superposition of locally emitted wavelets. With this technique, the small-amplitude dc current pattern is shown to form whistler wings at each electrode instead of the generally accepted Alfven wings. For the beam electrode, the whistler wing separates from the field-aligned beam which carries no net current. Large amplitude return currents to a stationary anode generate current-driven microinstabilities, parallel electric fields, ion depletions, current disruptions and time-varying electrode charging. At appropriately high potentials and neutral densities, excess neutrals are ionized near the anode. The anode sheath emits high-frequency electron transit-time oscillations at the sheath-plasma resonance. The beam generates Langmuir turbulence, ion sound turbulence, electron heating, space charge fields, and Hall currents. An insulated, perfectly conducting transmission line embedded in the plasma becomes lossy due to excitation of whistler waves and magnetic field diffusion effects. The implications of the laboratory observations on electrodynamic tethers in space are discussed.

IVGEN Post Flight Analysis

NASA Technical Reports Server (NTRS)

Mcquillen, John; Brown, Dan; Hussey, Sam; Zoldak, John

2014-01-01

The Intravenous Fluid Generation (IVGEN) Experiment was a technology demonstration experiment that purified ISS potable water, mixed it with salt, and transferred it through a sterilizing filter. On-orbit performance was verified as appropriate and two 1.5 l bags of normal saline solution were returned to earth for post-flight testing by a FDA certified laboratory for compliance with United States Pharmacopiea (USP) standards. Salt concentration deviated from required values and an analysis identified probable causes. Current efforts are focused on Total Organic Content (TOC) testing, and shelf life.The Intravenous Fluid Generation (IVGEN) Experiment demonstrated the purification of ISS potable water, the mixing of the purified water with sodium chloride, and sterilization of the solution via membrane filtration. On-orbit performance was monitored where feasible and two 1.5-liter bags of normal saline solution were returned to earth for post-flight testing by a FDA-registered laboratory for compliance with United States Pharmacopeia (USP)standards [1]. Current efforts have been focused on challenge testing with identified [2] impurities (total organic-carbon), and shelf life testing. The challenge testing flowed known concentrations of contaminants through the IVGEN deionizing cartridge and membrane filters to test their effectiveness. One finding was that the filters and DI-resin themselves contribute to the contaminant load during initial startup, suggesting that the first 100 ml of fluid be discarded. Shelf life testing is ongoing and involves periodic testing of stored DI cartridges and membrane filters that are capped and sealed in hermetic packages. The testing is conducted at six month intervals measuring conductivity and endotoxins in the effluent. Currently, the packaging technique has been successfully demonstrated for one year of storage testing. The USP standards specifies that the TOC be conducted at point of generation as opposed to point of consumption. Samples were generated and shipped to an FDA facility however, testing determined that the samples failed the TOC specification with most likely due to leaching from the sample container. Shelf life testing is examining packaging techniques and periodic testing of samples of DI cartridges that are capped and sealed in hermetic packages. Periodic testing of the purified water output will be conducted at six month intervals.

Vulnerability of Xylem Vessels to Cavitation in Sugar Maple. Scaling from Individual Vessels to Whole Branches1

PubMed Central

Melcher, Peter J.; Zwieniecki, Maciej A.; Holbrook, N. Michele

2003-01-01

The relation between xylem vessel age and vulnerability to cavitation of sugar maple (Acer saccharum Marsh.) was quantified by measuring the pressure required to force air across bordered pit membranes separating individual xylem vessels. We found that the bordered pit membranes of vessels located in current year xylem could withstand greater applied gas pressures (3.8 MPa) compared with bordered pit membranes in vessels located in older annular rings (2.0 MPa). A longitudinal transect along 6-year-old branches indicated that the pressure required to push gas across bordered pit membranes of current year xylem did not vary with distance from the growing tip. To understand the contribution of age-related changes in vulnerability to the overall resistance to cavitation, we combined data on the pressure thresholds of individual xylem vessels with measurements of the relative flow rate through each annual ring. The annual ring of the current year contributed only 16% of the total flow measured on 10-cm-long segments cut from 6-year-old branches, but it contributed more than 70% of the total flow when measured through 6-year-old branches to the point of leaf attachment. The vulnerability curve calculated using relative flow rates measured on branch segments were similar to vulnerability curves measured on 6-year-old branches (pressure that reduces hydraulic conductance by 50% = 1.6–2.4 MPa), whereas the vulnerability curve calculated using relative flow rates measured on 6-year-old branches were similar to ones measured on the extension growth of the current year (pressure that reduces hydraulic conductance by 50% = 3.8 MPa). These data suggest that, in sugar maple, the xylem of the current year can withstand larger xylem tensions than older wood and dominates water delivery to leaves. PMID:12692336

Phasing-out tobacco: proposal to deny access to tobacco for those born from 2000

PubMed Central

Khoo, Deborah; Chiam, Yvonne; Ng, Priscilla; Berrick, A J

2010-01-01

As a contribution to worldwide efforts towards a tobacco-free society, this paper considers the possibility of a long-term phasing-in of a total ban, by proposing that individuals born in or after the year 2000 have their supply of tobacco restricted. In conjunction, a survey that we have conducted in Singapore indicates strong public support (even among current smokers) for the proposal. PMID:20876075

Expert Water Quality Panel Review of Responses to the NASA Request for Information for the International Space Station On-Board Environmental Monitoring System

NASA Technical Reports Server (NTRS)

Fishman, Julianna L.; Mudgett, Paul D.; Packham, Nigel J.; Schultz, John R.; Straub, John E., II

2005-01-01

On August 9, 2003, NASA, with the cooperative support of the Vehicle Office of the International Space Station Program, the Advanced Human Support Technology Program, and the Johnson Space Center Habitability and Environmental Factors Office released a Request for Information, or RFI, to identify next-generation environmental monitoring systems that have demonstrated ability or the potential to meet defined requirements for monitoring air and water quality onboard the International Space Station. This report summarizes the review and analysis of the proposed solutions submitted to meet the water quality monitoring requirements. Proposals were to improve upon the functionality of the existing Space Station Total Organic Carbon Analyzer (TOCA) and monitor additional contaminants in water samples. The TOCA is responsible for in-flight measurement of total organic carbon, total inorganic carbon, total carbon, pH, and conductivity in the Space Station potable water supplies. The current TOCA requires hazardous reagents to accomplish the carbon analyses. NASA is using the request for information process to investigate new technologies that may improve upon existing capabilities, as well as reduce or eliminate the need for hazardous reagents. Ideally, a replacement for the TOCA would be deployed in conjunction with the delivery of the Node 3 water recovery system currently scheduled for November 2007.

An estimate of periodontal treatment needs in the U.S. based on epidemiologic data.

PubMed

Oliver, R C; Brown, L J; Löe, H

1989-07-01

It has generally been assumed, based on previous epidemiologic and utilization studies as well as the increasing elderly population, that there would be an increasing need for periodontal treatment. Analysis of a more recent household epidemiologic survey conducted in 1981 indicates that the need for treatment of periodontitis is less than previous estimates. These epidemiologic data have been translated into treatment needs through a series of conversion rules derived from previous studies and current patterns of treatment, and applied to the 1985 U.S. population. The total periodontal services needed for scaling, surgery, and prophylaxes would require 120 to 133 million hours and $5 to $6 billion annually if the total population were treated for periodontitis over a 4-year period. Only 11% of the total hours needed would be for scaling and surgery whereas 89% would be needed for prophylaxes. Expenditures for periodontal treatment total approximately 10% of the amount being spent on dental care in 1985. On the basis of these data, it seems unlikely that there will be a substantial increase in the need for periodontal treatment in a growing and aging U.S. population. These figures represent the upper limits of treatment need and are reduced by factoring in current utilization of periodontal treatment.

[Monitoring of extra- and intra-cellular compartment through total body impedance (author's transl)].

PubMed

Raggueneau, J L; Gambini, D; Levante, A; Riche, F; de Vernejoul, P; Echter, E

1979-01-01

To evaluate the extra-cellular space, we measure the impedance (or resistance) of the extra-cellular electrolyte compartment with an alternating current at a fixed frequency of 5 kHz that can't pass through the cellular membrane. Total water is measured by the impedance to a current of 1 MHz which is conducted by extra and intra cellular hydro-electrolytic space. There is a good correlation between electrical impedance measurements and distribution of isotopic markers. The extra-cellular compartment was evaluated by diffusion of D.T.P.A. marked with 99mTc or with 111In and the total water by the diffusion of Antipyrin marked with 1,311 or 1,231. The findings indicate that there is not a significant difference between the results of the size of extra-cellular water measured by electrical impedance and D.T.P.A. diffusion (r = 0.75). Comparable results have been obtained in the determination of total water by electrical impedance measure and diffusion of Antipyrin (r = 0.90). We have also studied by method of electric impedance:--The state of hydratation in head injured patients and after pituitary surgery.--The lean body mass and hydro-electrolyte compartments in pregnancy. Electrical impedance measure seems to be a simple and reliable method to assess the hydric state of patients.

Family medicine practice in Saudi Arabia: The current situation and Proposed Strategic Directions Plan 2020

PubMed Central

Al-Khaldi, Yahia M.; Al-Ghamdi, Essam A.; Al-Mogbil, Tariq I.; Al-Khashan, Hesham I.

2017-01-01

OBJECTIVES: The objectives of this study were to assess the current situation of the teaching and training of undergraduate and postgraduate programs in family medicine in KSA, assess the current practice of family medicine, and draw a roadmap to achieve Saudi vision 2020. MATERIALS AND METHODS: This study was conducted with the support and collaboration of the Primary Health Care Department of the Ministry of Health, Saudi Arabia, and World Health Organization (EMRO) in November 2015. Based on the literature review of previous studies conducted for similar purposes, relevant questionnaires were developed. These consisted of four forms, each of which was directed at a different authority to achieve the above-mentioned objectives. Data of all questionnaires were coded, entered, and analyzed using SPSS version 16. RESULTS: There are 2282 primary health-care centers (PHCCs), 60% of which are in rural areas. More than half of the PHCCs have a laboratory and more than one-third have a Radiology Department. Out of the 6107 physicians, 636 are family physicians (10%). All medical colleges have a family medicine department with a total staff of 170 medical teachers. Thirteen departments run family medicine courses of 4–8 weeks' duration for students. Fourteen colleges have internship programs in family medicine and four colleges have postgraduate centers for family medicine (27%). There are 95 training centers for Saudi Board (Saudi Board of Family Medicine [SBFM]) and 68 centers for Saudi Diploma (Saudi Diploma of Family Medicine [SDFM]). The total number of trainers was 241, while the total trainees were 756 in SBFM and 137 in SDFM. CONCLUSIONS: This survey showed that there is a shortage of qualified family physicians in all health sectors in Saudi Arabia as a result of the lack of a strategic plan for the training of family physicians. A national strategic plan with specific objectives and an explicit budget are necessary to deal with this shortage and improve the quality of health-care services at PHCCs. PMID:28932160

Family medicine practice in Saudi Arabia: The current situation and Proposed Strategic Directions Plan 2020.

PubMed

Al-Khaldi, Yahia M; Al-Ghamdi, Essam A; Al-Mogbil, Tariq I; Al-Khashan, Hesham I

2017-01-01

The objectives of this study were to assess the current situation of the teaching and training of undergraduate and postgraduate programs in family medicine in KSA, assess the current practice of family medicine, and draw a roadmap to achieve Saudi vision 2020. This study was conducted with the support and collaboration of the Primary Health Care Department of the Ministry of Health, Saudi Arabia, and World Health Organization (EMRO) in November 2015. Based on the literature review of previous studies conducted for similar purposes, relevant questionnaires were developed. These consisted of four forms, each of which was directed at a different authority to achieve the above-mentioned objectives. Data of all questionnaires were coded, entered, and analyzed using SPSS version 16. There are 2282 primary health-care centers (PHCCs), 60% of which are in rural areas. More than half of the PHCCs have a laboratory and more than one-third have a Radiology Department. Out of the 6107 physicians, 636 are family physicians (10%). All medical colleges have a family medicine department with a total staff of 170 medical teachers. Thirteen departments run family medicine courses of 4-8 weeks' duration for students. Fourteen colleges have internship programs in family medicine and four colleges have postgraduate centers for family medicine (27%). There are 95 training centers for Saudi Board (Saudi Board of Family Medicine [SBFM]) and 68 centers for Saudi Diploma (Saudi Diploma of Family Medicine [SDFM]). The total number of trainers was 241, while the total trainees were 756 in SBFM and 137 in SDFM. This survey showed that there is a shortage of qualified family physicians in all health sectors in Saudi Arabia as a result of the lack of a strategic plan for the training of family physicians. A national strategic plan with specific objectives and an explicit budget are necessary to deal with this shortage and improve the quality of health-care services at PHCCs.

The dynamics of total outputs of Indonesian industrial sectors: A further study

NASA Astrophysics Data System (ADS)

Zuhdi, Ubaidillah

2017-03-01

The purpose of the current study is to extend the previous studies which analyze the impacts of final demands modifications on the total outputs of industrial sectors of a particular country. More specifically, the study conducts the analysis regarding the impacts on the total outputs of Indonesian industrial sectors. The study employs a demand-pull Input-Output (IO) quantity model, one of the calculation instruments in the IO analysis. The study focuses on seventeen industries. There are two scenarios used in this study, namely other final demands and import modifications. The “whole sector change” condition is implemented in the calculations. An initial period in this study is 2010. The results show that the positive impacts on the total outputs of focused sectors are distributed by scenario 1, the change of other final demands. On the contrary, the negative impacts are delivered by scenario 2, the modification of imports. The suggestions for improving the total outputs of discussed industries are based on the results.

Reconstruction of Cell Surface Densities of Ion Pumps, Exchangers, and Channels from mRNA Expression, Conductance Kinetics, Whole-Cell Calcium, and Current-Clamp Voltage Recordings, with an Application to Human Uterine Smooth Muscle Cells

PubMed Central

Atia, Jolene; McCloskey, Conor; Shmygol, Anatoly S.; Rand, David A.; van den Berg, Hugo A.; Blanks, Andrew M.

2016-01-01

Uterine smooth muscle cells remain quiescent throughout most of gestation, only generating spontaneous action potentials immediately prior to, and during, labor. This study presents a method that combines transcriptomics with biophysical recordings to characterise the conductance repertoire of these cells, the ‘conductance repertoire’ being the total complement of ion channels and transporters expressed by an electrically active cell. Transcriptomic analysis provides a set of potential electrogenic entities, of which the conductance repertoire is a subset. Each entity within the conductance repertoire was modeled independently and its gating parameter values were fixed using the available biophysical data. The only remaining free parameters were the surface densities for each entity. We characterise the space of combinations of surface densities (density vectors) consistent with experimentally observed membrane potential and calcium waveforms. This yields insights on the functional redundancy of the system as well as its behavioral versatility. Our approach couples high-throughput transcriptomic data with physiological behaviors in health and disease, and provides a formal method to link genotype to phenotype in excitable systems. We accurately predict current densities and chart functional redundancy. For example, we find that to evoke the observed voltage waveform, the BK channel is functionally redundant whereas hERG is essential. Furthermore, our analysis suggests that activation of calcium-activated chloride conductances by intracellular calcium release is the key factor underlying spontaneous depolarisations. PMID:27105427

Ions in Wine and Their Relation to Electrical Conductivity Under Ultrasound Irradiation.

PubMed

Yan, Yan-Ying; Zhang, Qing-An; Li, Er-Chun; Zhang, Ya-Feng

2017-09-01

Change in electrical conductivity is considered a potential indicator for the on-line monitoring of wine aging accelerated by ultrasound, as determined in our previous study; however, the exact mechanism of change is currently unclear. In this study, the ion content and the total ionic strength were analyzed by ion-exchange chromatography to investigate the change mechanism of the electrical conductivity of wine under ultrasound irradiation. The results indicate that the changes in wine electrical conductivity during ultrasound treatment correlate with the changes in the cations (Na+, K+, Ca2+, Mg2+, and NH4+) and in the anions from the organic acids (malic acid, citric acid, tartaric acid, oxalic acid, and formic acid) and inorganic acids (Cl-, SO42-, and PO43-), especially for the ionic strength of the wine. Overall, electrical conductivity may be used to reflect the chemical reactions related to wine aging to a certain extent because the reactions can be initiated by the conversion of cations and by the degradation or auxiliary function of organic acids.

Controlled Sonar Exposure Experiments on Cetaceans in Norwegian Waters: Overview of the 3S-Project.

PubMed

Lam, Frans-Peter A; Kvadsheim, Petter H; Miller, Patrick J O; Tyack, Peter L; Ainslie, Michael A; Curé, Charlotte; Kleivane, Lars; Sivle, Lise Doksæter; van Ijsselmuide, Sander P; Visser, Fleur; von Benda-Beckmann, Alexander M; Wensveen, Paul J; Dekeling, René P A

2016-01-01

In mitigating the risk of sonar operations, the behavioral response of cetaceans is one of the major knowledge gaps that needs to be addressed. The 3S-Project has conducted a number of controlled exposure experiments with a realistic sonar source in Norwegian waters from 2006 to 2013. In total, the following six target species have been studied: killer, long-finned pilot, sperm, humpback, minke, and northern bottlenose whales. A total of 38 controlled sonar exposures have been conducted on these species. Responses from controlled and repeated exposure runs have been recorded using acoustic and visual observations as well as with electronic tags on the target animal. So far, the first dose-response curves as well as an overview of the scored severity of responses have been revealed. In this paper, an overview is presented of the approach for the study, including the results so far as well as the current status of the ongoing analysis.

The effect of impurities and incident angle on the secondary electron emission of Ni(110)

NASA Astrophysics Data System (ADS)

Lazar, Hadar; Patino, Marlene; Raitses, Yevgeny; Koel, Bruce E.; Gentile, Charles; Feibush, Eliot

2015-11-01

The investigation of secondary electron emission (SEE) of conducting materials used for magnetic fusion devices and plasma thrusters is important for determining device lifetime and performance. Methods to quantify the secondary electron emission from conducting materials and to characterize the effects that impurities and incident angles have on secondary electron emission were developed using 4-grid low energy electron diffraction (LEED) optics. The total secondary electron yield from a Ni(110) surface was continuously measured from the sample current as surface contamination increased from reactions with background gases in the ultrahigh vacuum chamber. Auger electron spectroscopy (AES) and temperature programmed desorption (TPD) were used to examine the composition and impurity levels on the Ni(110) surface. The total secondary electron yield was also measured at different incident angles. Thank you to the Princeton Plasma Physics Laboratory and the Department of Energy for the opportunity to work on this project through the Science Undergraduate Laboratory Internships.

The effects of impurities and incidence angle on the secondary electron emission of Ni(110)

NASA Astrophysics Data System (ADS)

Lazar, Hadar; Patino, Marlene; Raitses, Yevgeny; Koel, Bruce; Gentile, Charles; Feibush, Eliot

The investigation of secondary electron emission (SEE) of conducting materials used for magnetic fusion devices and plasma thrusters is important for determining device lifetime and performance. Methods to quantify the secondary electron emission from conducting materials and to characterize the effects that impurities and incidence angles have on secondary electron emission were developed using 4-grid low energy electron diffraction (LEED) optics. The total secondary electron yield from a Ni(110) surface was continuously measured from the sample current as surface contamination increased from reactions with background gases in the ultrahigh vacuum chamber. Auger electron spectroscopy (AES) and temperature programmed desorption (TPD) were used to examine the composition and impurity levels on the Ni(110) surface. The total secondary electron yield was also measured at different incidence angles. Thank you to the Princeton Plasma Physics Laboratory (PPPL) and the Department of Energy (DOE) for the opportunity to work on this project through the Science Undergraduate Laboratory Internships (SULI).

Nicotinic acetylcholine receptors in porcine hypophyseal intermediate lobe cells.

PubMed Central

Zhang, Z W; Feltz, P

1990-01-01

1. Acetylcholine (ACh) was found to depolarize isolated porcine intermediate lobe cells maintained in primary cells culture. We investigated the ACh-induced responses in both whole-cell and cell-attached configurations of the patch-clamp technique. 2. From noise analysis of ACh-evoked whole-cell currents, we estimated an elementary conductance of 20 pS and a channel open duration of about 1.7 ms at -60 mV. From single-channel recordings, we obtained a slope conductance of 26 pS and a mean open time of 1.8 ms at membrane potentials between -60 and -80 mV. 3. ACh-evoked responses were blocked by d-tubocurarine (d-TC), hexamethonium and mecamylamine, but were insensitive to alpha-bungarotoxin. These characteristics define a neuronal type of nicotinic receptors. 4. The whole-cell current induced by ACh showed a strong inward rectification with no outward current being obtained. This phenomenon was observed when the intracellular ion is either sodium or caesium, and even when Ca2+ and Mg2+ were totally removed from the intracellular medium. 5. ACh-gated channels in intermediate lobe cells were cation selective and were permeable to Na+ and Cs+. In Ca2(+)-free extracellular solution, single-channel conductances were much larger (46 pS) than in the presence of 2 mM-Ca2+ (26 pS). 6. The possibility of an excitatory cholinergic control of intermediate lobe cells is discussed. PMID:1693685

Silicon quantum dots embedded in a SiO2 matrix: From structural study to carrier transport properties

NASA Astrophysics Data System (ADS)

Garcia-Castello, Nuria; Illera, Sergio; Guerra, Roberto; Prades, Joan Daniel; Ossicini, Stefano; Cirera, Albert

2013-08-01

We study the details of electronic transport related to the atomistic structure of silicon quantum dots embedded in a silicon dioxide matrix using ab initio calculations of the density of states. Several structural and composition features of quantum dots (QDs), such as diameter and amorphization level, are studied and correlated with transport under transfer Hamiltonian formalism. The current is strongly dependent on the QD density of states and on the conduction gap, both dependent on the dot diameter. In particular, as size increases, the available states inside the QD increase, while the QD band gap decreases due to relaxation of quantum confinement. Both effects contribute to increasing the current with the dot size. Besides, valence band offset between the band edges of the QD and the silica, and conduction band offset in a minor grade, increases with the QD diameter up to the theoretical value corresponding to planar heterostructures, thus decreasing the tunneling transmission probability and hence the total current. We discuss the influence of these parameters on electron and hole transport, evidencing a correlation between the electron (hole) barrier value and the electron (hole) current, and obtaining a general enhancement of the electron (hole) transport for larger (smaller) QD. Finally, we show that crystalline and amorphous structures exhibit enhanced probability of hole and electron current, respectively.

Electrochemical treatment of cork boiling wastewater with a boron-doped diamond anode.

PubMed

Fernandes, Annabel; Santos, Diana; Pacheco, Maria José; Ciríaco, Lurdes; Simões, Rogério; Gomes, Arlindo C; Lopes, Ana

2015-01-01

Anodic oxidation at a boron-doped diamond anode of cork boiling wastewater was successfully used for mineralization and biodegradability enhancement required for effluent discharge or subsequent biological treatment, respectively. The influence of the applied current density (30-70 mA/cm2) and the background electrolyte concentration (0-1.5 g/L Na2SO4) on the performance of the electrochemical oxidation was investigated. The supporting electrolyte was required to achieve conductivities that enabled anodic oxidation at the highest current intensities applied. The results indicated that pollutant removal increased with the applied current density, and after 8 h, reductions greater than 90% were achieved for COD, dissolved organic carbon, total phenols and colour. The biodegradability enhancement was from 0.13 to 0.59 and from 0.23 to 0.72 for the BOD/COD ratios with BOD of 5 and 20 days' incubation period, respectively. The tests without added electrolyte were performed at lower applied electrical charges (15 mA/cm2 or 30 V) with good organic load removal (up to 80%). For an applied current density of 30 mA/cm2, there was a minimum of electric conductivity of 1.9 mS/cm (corresponding to 0.75 g/L of Na2SO4), which minimized the specific energy consumption.

Total particle, sulfate, and acidic aerosol emissions from kerosene space heaters

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

Leaderer, B.P.; Boone, P.M.; Hammond, S.K.

1990-06-01

Chamber studies were conducted on four unvented kerosene space heaters to assess emissions of total particle, sulfate, and acidic aerosol. The heaters tested represented four burner designs currently in use by the public. Kerosene space heaters are a potential source of fine particles ({<=} 2.5-{mu}m diameter), sulfate, and acidic aerosol indoors. Fine particle concentrations in homes in which the heaters are used may be increased in excess of 20 {mu}g/m{sup 3} over background levels. Sulfate and acidic aerosol levels in such homes could exceed average and peak outdoor concentrations. Maltuned heaters could produce exceptionally high levels of all air contaminantsmore » measured.« less

Geophysical monitoring of solute transport in dual-domain environments through laboratory experiments, field-scale solute tracer tests, and numerical simulation

NASA Astrophysics Data System (ADS)

Swanson, Ryan David

The advection-dispersion equation (ADE) fails to describe non-Fickian solute transport breakthrough curves (BTCs) in saturated porous media in both laboratory and field experiments, necessitating the use of other models. The dual-domain mass transfer (DDMT) model partitions the total porosity into mobile and less-mobile domains with an exchange of mass between the two domains, and this model can reproduce better fits to BTCs in many systems than ADE-based models. However, direct experimental estimation of DDMT model parameters remains elusive and model parameters are often calculated a posteriori by an optimization procedure. Here, we investigate the use of geophysical tools (direct-current resistivity, nuclear magnetic resonance, and complex conductivity) to estimate these model parameters directly. We use two different samples of the zeolite clinoptilolite, a material shown to demonstrate solute mass transfer due to a significant internal porosity, and provide the first evidence that direct-current electrical methods can track solute movement into and out of a less-mobile pore space in controlled laboratory experiments. We quantify the effects of assuming single-rate DDMT for multirate mass transfer systems. We analyze pore structures using material characterization methods (mercury porosimetry, scanning electron microscopy, and X-ray computer tomography), and compare these observations to geophysical measurements. Nuclear magnetic resonance in conjunction with direct-current resistivity measurements can constrain mobile and less-mobile porosities, but complex conductivity may have little value in relation to mass transfer despite the hypothesis that mass transfer and complex conductivity lengths scales are related. Finally, we conduct a geoelectrical monitored tracer test at the Macrodispersion Experiment (MADE) site in Columbus, MS. We relate hydraulic and electrical conductivity measurements to generate a 3D hydraulic conductivity field, and compare to hydraulic conductivity fields estimated through ordinary kriging and sequential Gaussian simulation. Time-lapse electrical measurements are used to verify or dismiss aspects of breakthrough curves for different hydraulic conductivity fields. Our results quantify the potential for geophysical measurements to infer on single-rate DDMT parameters, show site-specific relations between hydraulic and electrical conductivity, and track solute exchange into and out of less-mobile domains.

An assessment of tailoring of lightning protection design requirements for a composite wing structure on a metallic aircraft

NASA Technical Reports Server (NTRS)

Harwood, T. L.

1991-01-01

The Navy A-6E aircraft is presently being modified with a new wing which uses graphite/epoxy structures and substructures around a titanium load-bearing structure. The ability of composites to conduct electricity is less than that of aluminum. This is cause for concern when the wing may be required to conduct large lightning currents. The manufacturer attempted to solve lightning protection issues by performing a risk assessment based on a statistical approach which allows relaxation of the wing lightning protection design levels over certain locations of the composite wing. A sensitivity study is presented designed to define the total risk of relaxation of the design levels.

Electrocoagulation of wastewater from almond industry.

PubMed

Valero, David; Ortiz, Juan M; García, Vicente; Expósito, Eduardo; Montiel, Vicente; Aldaz, Antonio

2011-08-01

This work was carried out to study the treatment of almond industry wastewater by the electrocoagulation process. First of all, laboratory scale experiments were conducted in order to determine the effects of relevant wastewater characteristics such as conductivity and pH, as well as the process variables such as anode material, current density and operating time on the removal efficiencies of the total organic carbon (TOC) and the most representative analytical parameters. Next, the wastewater treatment process was scaled up to pre-industrial size using the best experimental conditions and parameters obtained at laboratory scale. Finally, economic parameters such as chemicals, energy consumption and sludge generation have been discussed. Copyright © 2011 Elsevier Ltd. All rights reserved.

Prescribing patterns for upper respiratory tract infections: a prescription-review of primary care practice in Kedah, Malaysia, and the implications.

PubMed

Rezal, Rabiatul Salmi; Hassali, Mohamed Azmi; Alrasheedy, Alian A; Saleem, Fahad; Yusof, Faridah Aryani Md; Kamal, Mardhiyah; Mohd Din, Rosminah; Godman, Brian

2015-01-01

It is necessary to ascertain current prescribing of antibiotics for upper respiratory tract infections (URTIs) to address potential overuse. A retrospective analysis was conducted of all prescriptions for URTIs among 10 public primary healthcare centers in Kedah, Malaysia, from 1 January to 31 March 2014. A total of 123,524 prescriptions were screened and analyzed. Of these, 7129 prescriptions were for URTI, with 31.8% (n = 2269) containing antibiotics. Macrolides were the most commonly prescribed antibiotic, constituting 61% (n = 1403) of total antibiotics prescribed. There was a statistically significant association between different prescribers and diagnoses (p = 0.001) and a weak positive trend suggesting family medicine specialists are more competent in antibiotic prescribing, followed by medical officers and assistant medical officers (τ = 0.122). Prescribing practices of some prescribers were inconsistent with current guidelines encouraging resistance development. National antimicrobial stewardship programs and further educational initiatives are ongoing in Malaysia to improve antibiotic use.

Effect of abalone farming on seawater movement and benthic foraminiferal assemblage of Zostera marina in the inner bay of Wando, South Korea.

PubMed

Lee, Yeon Gyu; Choi, Yang Ho; Jeong, Da Un; Lee, Jung Sick; Kim, Yong Wan; Park, Jung Jun; Choi, Jae Ung

2016-08-15

Tidal current survey as well as geochemical and benthic foraminiferal analyses of sediment cores were conducted in an abalone farm and a Zostera bed to understand the degree to which the abalone farm facilities installed along a channel in a shallow sea affect the benthic environment and ecology. In the abalone farm, Ammonia beccarii-Pseudoparrella naraensis-Elphidium somaense-Rosalina globularis-Trochammina hadai and P. naraensis-E. somaense-A. beccarii-T. hadai assemblages appeared owing to an increase in the total nitrogen content from the biodeposits. The Zostera bed consisted of A. beccarii-P. naraensis-Buccella frigida-T. hadai assemblage owing to the gradual expansion of a brackish shallow-water environment by the rapidly decreasing current speed, and it may have flourished. Moreover, the total sulfur, Zn, Cr, and Cu contents in the sediments decreased remarkably more than those of the pre-abalone farming did, caused by the vigorous activity of Zostera marina physiology. Copyright © 2016 Elsevier Ltd. All rights reserved.

Nanoscale Surface Modifications of Orthopaedic Implants: State of the Art and Perspectives

PubMed Central

Staruch, RMT; Griffin, MF; Butler, PEM

2016-01-01

Background: Orthopaedic implants such as the total hip or total knee replacement are examples of surgical interventions with postoperative success rates of over 90% at 10 years. Implant failure is associated with wear particles and pain that requires surgical revision. Improving the implant - bone surface interface is a key area for biomaterial research for future clinical applications. Current implants utilise mechanical, chemical or physical methods for surface modification. Methods: A review of all literature concerning the nanoscale surface modification of orthopaedic implant technology was conducted. Results: The techniques and fabrication methods of nanoscale surface modifications are discussed in detail, including benefits and potential pitfalls. Future directions for nanoscale surface technology are explored. Conclusion: Future understanding of the role of mechanical cues and protein adsorption will enable greater flexibility in surface control. The aim of this review is to investigate and summarise the current concepts and future directions for controlling the implant nanosurface to improve interactions. PMID:28217214

Axial and radial water flow in the trunks of oak trees: a quantitative and qualitative analysis.

PubMed

Granier, A; Anfodillo, T; Sabatti, M; Cochard, H; Dreyer, E; Tomasi, M; Valentini, R; Bréda, N

1994-12-01

Axial water flow in the trunks of mature oak trees (Quercus petraea (Matt.) Liebl. and Q. robur L.) was studied by four independent techniques: water absorption from a cut trunk, sap flowmeters, heat pulse velocity (HPV) and thermoimaging. Estimation of the total water flow with sap flowmeters, HPV and water absorption yielded comparable results. We concluded from dye colorations, thermograms and axial profiles of sap flow and heat pulse velocity that, in intact trunks, most of the flow occurred in the current-year ring, where early-wood vessels in the outermost ring were still functional. Nevertheless, there was significant flow in the older rings of the xylem. Total water flow through the trunk was only slightly reduced when air embolisms were artificially induced in early-wood vessels, probably because there was little change in hydraulic conductance in the root-leaf sap pathway. Embolization of the current-year vessels reactivated transport in the older rings.

Improving Access to Care for Warfighters: Virtual Worlds Technology to Enhance Primary Care Training in Post-Traumatic Stress and Motivational Interviewing

DTIC Science & Technology

2016-10-01

creating content, then, build off the BIM (P9) 9. Keep the training relevant with current events in the medical world (zika, infectious disease , etc... training ; curriculum development; motivational interviewing Veterans present to primary care providers (PCPs) with posttraumatic stress (PTS) symptoms...can inform the training curriculum. In total, 11 interviews were conducted with primary care providers and healthcare leadership. The data was

How an antenna launches its input power into radiation: thepattern of the Poynting vector at and near an antenna

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

Jackson, J.D.

2005-05-18

In this paper I first address the question of whether theseat of the power radiated by an antenna made of conducting members isdistributed over the "arms" of the antenna according tomore » $$ - \\bf J \\cdotE$$, where $$\\bf J$$ is the specified current density and $$\\bf E$$ is theelectric field produced by that source. Poynting's theorem permits only aglobal identification of the total input power, usually from a localizedgenerator, with the total power radiated to infinity, not a localcorrespondence of $$- \\bf J \\cdot E\\ d^3x $$ with some specific radiatedpower, $$r^2 \\bf S \\cdot \\hat r\\ d\\Omega $$. I then describe a modelantenna consisting of two perfectly conducting hemispheres of radius\\emph a separated by a small equatorial gap across which occurs thedriving oscillatory electric field. The fields and surface current aredetermined by solution of the boundary value problem. In contrast to thefirst approach (not a boundary value problem), the tangential electricfield vanishes on the metallic surface. There is no radial Poyntingvector at the surface. Numerical examples are shown to illustrate how theenergy flows from the input region of the gap and is guided near theantenna by its "arms" until it is launched at larger \\emph r/a into theradiation pattern determined by the value of \\emph ka.« less

Improved Ionospheric Electrodynamic Models and Application to Calculating Joule Heating Rates

NASA Technical Reports Server (NTRS)

Weimer, D. R.

2004-01-01

Improved techniques have been developed for empirical modeling of the high-latitude electric potentials and magnetic field aligned currents (FAC) as a function of the solar wind parameters. The FAC model is constructed using scalar magnetic Euler potentials, and functions as a twin to the electric potential model. The improved models have more accurate field values as well as more accurate boundary locations. Non-linear saturation effects in the solar wind-magnetosphere coupling are also better reproduced. The models are constructed using a hybrid technique, which has spherical harmonic functions only within a small area at the pole. At lower latitudes the potentials are constructed from multiple Fourier series functions of longitude, at discrete latitudinal steps. It is shown that the two models can be used together in order to calculate the total Poynting flux and Joule heating in the ionosphere. An additional model of the ionospheric conductivity is not required in order to obtain the ionospheric currents and Joule heating, as the conductivity variations as a function of the solar inclination are implicitly contained within the FAC model's data. The models outputs are shown for various input conditions, as well as compared with satellite measurements. The calculations of the total Joule heating are compared with results obtained by the inversion of ground-based magnetometer measurements. Like their predecessors, these empirical models should continue to be a useful research and forecast tools.

The Quality of Educational Services from Students' Viewpoint in Iran: A Systematic Review and Meta-analysis.

PubMed

Moosavi, Ahmad; Mohseni, Mohammad; Ziaiifar, Hajar; Azami-Aghdash, Saber; Gharasi Manshadi, Mahdi; Rezapour, Aziz

2017-04-01

Students' view is an important factor in assessing the quality of universities. Servqual pattern is regarded as the most prominent for services quality measurement. This study aimed to review systematically studies that investigated the quality of educational services. A systematic review and meta-analysis of studies evaluating students' viewpoint about quality of educational services were conducted. Required data were collected from PubMed, Embase, Scopus, Science Direct, Google Scholar, SID, Magiran, and Iranmedex, without time restriction. Computer software CMA, ver. 2 was applied to estimate the total mean score of students' perception and expectation of services quality and the gap between them. The 18 eligible studies were entered into study. The studies were conducted between 2004 and 2014. Based on the random effect model, the total mean score of students' perception, students' expectation and the gap between them were estimated 2.92 (95% CI, 2.75 - 3.09), 4.18 (95% CI, 3.98 - 4.38), respectively and -1.30 (95% CI= -1.56, -1.04). The studied students' expectation level is higher than the current quality of educational services. There is a tangible difference between their expectations and the current quality, which requires officials' efforts to improve quality in all dimensions and effective steps can be taken towards improving the quality of educational services through appropriate training planning and training for empowering employees in colleges and universities.

Predicting the vertical structure of tidal current and salinity in San Francisco Bay, California

USGS Publications Warehouse

Ford, Michael; Wang, Jia; Cheng, Ralph T.

1990-01-01

A two-dimensional laterally averaged numerical estuarine model is developed to study the vertical variations of tidal hydrodynamic properties in the central/north part of San Francisco Bay, California. Tidal stage data, current meter measurements, and conductivity, temperature, and depth profiling data in San Francisco Bay are used for comparison with model predictions. An extensive review of the literature is conducted to assess the success and failure of previous similar investigations and to establish a strategy for development of the present model. A σ plane transformation is used in the vertical dimension to alleviate problems associated with fixed grid model applications in the bay, where the tidal range can be as much as 20–25% of the total water depth. Model predictions of tidal stage and velocity compare favorably with the available field data, and prototype salinity stratification is qualitatively reproduced. Conclusions from this study as well as future model applications and research needs are discussed.

Feasibility study for long lifetime helium dewar

NASA Technical Reports Server (NTRS)

Parmley, R. T.

1981-01-01

A feasible concept for a launchable three year lifetime helium dewar was investigted. Current helium dewar designs were examined to see where the largest potential reductions in parasitic heat loads can be made. The study was also devoted to examining support concepts. The support concept chosen, a passive orbital disconnect strut (PODS), has an orbital support conductance that is lower by more than an order of magnitude over current tension band supports. This lower support conductance cuts the total dewar weight in half for the same three year life time requirements. Effort was also concentrated on efficient wire feed through designs and vapor cooling of the multilayer insulation, supports, wire feed throughs and plumbing penetrations. A single stage helium dewar vs. dual stage dewars with a guard cryogen of nitrogen or neon was examined. The single stage dewar concept was selected. Different support concepts were analyzed from which the PODS support concepts was chosen. A preliminary design of the dewar was thermally and structurally analyzed and laid out including system weights, thermal performance and performance sensitivities.

Quantitative evaluation of spatial scale of carrier trapping at grain boundary by GHz-microwave dielectric loss spectroscopy

NASA Astrophysics Data System (ADS)

Choi, W.; Tsutsui, Y.; Miyakai, T.; Sakurai, T.; Seki, S.

2017-11-01

Charge carrier mobility is an important primary parameter for the electronic conductive materials, and the intrinsic limit of the mobility has been hardly access by conventional direct-current evaluation methods. In the present study, intra-grain hole mobility of pentacene thin films was estimated quantitatively using microwave-based dielectric loss spectroscopy (time-resolved microwave conductivity measurement) in alternating current mode of charge carrier local motion. Metal-insulator-semiconductor devices were prepared with different insulating polymers or substrate temperature upon vacuum deposition of the pentacene layer, which afforded totally four different grain-size conditions of pentacene layers. Under the condition where the local motion was determined by interfacial traps at the pentacene grain boundaries (grain-grain interfaces), the observed hole mobilities were plotted against the grain sizes, giving an excellent correlation fit successfully by a parabolic function representative of the boarder length. Consequently, the intra-grain mobility and trap-release time of holes were estimated as 15 cm2 V-1 s-1 and 9.4 ps.

Conductive diamond sono-electrochemical disinfection (CDSED) for municipal wastewater reclamation.

PubMed

Llanos, Javier; Cotillas, Salvador; Cañizares, Pablo; Rodrigo, Manuel A

2015-01-01

In the present work, the disinfection of actual effluents from a municipal wastewater treatment plant (WWTP) by a conductive diamond sono-electrochemical process was assessed. First, efficiency of single electrodisinfection process with diamond anodes (without the contribution of ultrasounds) was studied, finding that the total disinfection can be attained at current charges applied below 0.02kAhm(-3). It was also found that the main disinfection mechanism is the attack of Escherichia coli (E. coli) by the disinfectants produced in the electrochemical cell and that the production of chlorates is avoided when working at current densities not higher than 1.27Am(-2). Next, a marked synergistic effect was found when coupling ultrasound (US) irradiation to the electrochemical system (sono-electrochemical disinfection). This increase in the disinfection rate was found to be related to the suppression of the agglomeration of E. coli cells and the enhancement in the production of disinfectant species. Copyright © 2014 Elsevier B.V. All rights reserved.

Tranexamic acid for the management of uterine fibroid tumors: A systematic review of the current evidence

PubMed Central

Peitsidis, Panagiotis; Koukoulomati, Anna

2014-01-01

AIM: To conduct a detailed systematic review of the current evidence on the administration and efficacy of tranexamic acid in patients with menorrhagia due to uterine fibroids. METHODS: We conducted an electronic search on the following databases PubMed and Medline (1950-2013); (1980-2013); Cochrane library (1993-2013). RESULTS: A total of 36 articles were retrieved after the initial electronic search. Careful assessment of the retrieved studies led to the final selection of 5 articles for inclusion in the review. CONCLUSION: Tranexamic acid may reduce blood loss perioperatively in myomectomies. It may reduce the menorrhagia in patients with fibroids, however a stratification of fibroids by size and location is required to define the responses. It is safe in general, with mild adverse effects observed in some cases. More studies with a double-blind randomized design and larger numbers of participants are necessary to reach more precise and safe conclusions. PMID:25516866

[Relationship between occupational stress and mental health in offshore oil platform workers].

PubMed

Wu, Hongtao; Xiao, Taiqin; Zou, Jianfang; Shan, Yongle; Li, Zijian

2014-02-01

To investigate the relationship between occupational stress and mental health in offshore oil platform workers and to provide a scientific basis for protection of their mental health. A total of 768 workers on offshore oil platform were surveyed with the Occupational Stress Inventory Revised Edition and Symptom Check List-90 (SCL-90). The total score of Occupational Role Questionnaire (ORQ) for the workers (160.27±24.63) was significantly lower than the national norm (166.52±27.01) (P < 0.01); the total score of Personal Strain Questionnaire (PSQ) (101.96±19.8) was significantly higher than the national norm (92.45±17.33) (P < 0.01). The total score of Personal Resource Questionnaire (PRQ) for the workers was not significantly different from the national norm (P > 0.05), but the items of recreation, social support, and rational/cognitive found significant difference (P < 0.05). The total score of SCL-90 was positively correlated with all items of ORQ and PSQ (P < 0.01) and negatively correlated with all items of PRQ (P < 0.01). The multiple stepwise regression analysis showed that current work seniority, education background, drinking, role overload, role insufficiency, role ambiguity, responsibility, physical environment, and rational/cognitive conduct impacted the score of SCL-90 (P < 0.05). The mental health of workers on offshore oil platform is related to occupational stress, and role overload, role ambiguity, physical environment, and rational/cognitive conduct, etc, are closely associated with the workers' mental health.

Very-high thermal and electrical conductivity in overpressure-processed Bi2Sr2CaCu2O8+x wires

NASA Astrophysics Data System (ADS)

Bonura, M.; Avitabile, F.; Barth, C.; Jiang, J.; Larbalestier, D.; Fête, A.; Leo, A.; Bottura, L.; Senatore, C.

2018-05-01

The residual-resistivity ratio (RRR) of the normal-metal matrix is a key parameter for the electrical and thermal stability of technical superconductors. In Bi2Sr2CaCu2 {{{O}}}8+x (Bi-2212) round wires, the precursor powders are embedded in a Ag matrix without any diffusion barrier, and elemental diffusion from the superconducting filaments into the Ag might be expected to contaminate the matrix during the melt processing required for high critical current density development. This work shows that the overpressure processing, which is adopted to enhance the critical current performance, improves the thermal and electrical conductivities of the conductor, too. In the case of wires reacted with a standard processing performed in 1 bar O2, the RRR of the Ag matrix is about 90, in spite of the simple conductor design that does not include diffusion barriers. Increasing the total reaction pressure to 100 bar improves the RRR to about 200. The differences in RRR reflect on the thermal conductivity of the whole conductor, which has been investigated in magnetic fields up to 19 T.

Effects of fullerene coalescence on the thermal conductivity of carbon nanopeapods

NASA Astrophysics Data System (ADS)

Li, Jiaqian; Shen, Haijun

2018-05-01

The heat conduction and its dependence on fullerene coalescence in carbon nanopeapods (CNPs) have been investigated by equilibrium molecular dynamics simulations. The effects of fullerene coalescence on the thermal conductivity of CNPs were discussed under different temperatures. It is shown that the thermal conductivity of the CNPs decreases with the coalescence of encapsulated fullerene molecules. The thermal transmission mechanism of the effect of fullerene coalescence was analysed by the mass transfer contribution, the relative contributions of phonon oscillation frequencies to total heat current and the phonon vibrational density of states (VDOS). The mass transfer in CNPs is mainly attributed to the motion of encapsulated fullerene molecule and it gets more restricted with the coalescence of the fullerene. It shows that the low-frequency phonon modes below 20 THz contribute mostly to thermal conductivity in CNPs. The analysis of VDOS demonstrates that the dominating contribution to heat transfer is from the inner fullerene chain. With the coalescence of fullerene, the interfacial heat transfer between the CNT and fullerene chain is strengthened; however, the heat conduction of the fullerene chain decreases more rapidly at the same time.

Pacemaker Dependency after Cardiac Surgery: A Systematic Review of Current Evidence

PubMed Central

2015-01-01

Background Severe postoperative conduction disturbances requiring permanent pacemaker implantation frequently occur following cardiac surgery. Little is known about the long-term pacing requirements and risk factors for pacemaker dependency in this population. Methods We performed a systematic review of the literature addressing rates and predictors of pacemaker dependency in patients requiring permanent pacemaker implantation after cardiac surgery. Using a comprehensive search of the Medline, Web of Science and EMBASE databases, studies were selected for review based on predetermined inclusion and exclusion criteria. Results A total of 8 studies addressing the endpoint of pacemaker-dependency were identified, while 3 studies were found that addressed the recovery of atrioventricular (AV) conduction endpoint. There were 10 unique studies with a total of 780 patients. Mean follow-up ranged from 6–72 months. Pacemaker dependency rates ranged from 32%-91% and recovery of AV conduction ranged from 16%-42%. There was significant heterogeneity with respect to the definition of pacemaker dependency. Several patient and procedure-specific variables were found to be independently associated with pacemaker dependency, but these were not consistent between studies. Conclusions Pacemaker dependency following cardiac surgery occurs with variable frequency. While individual studies have identified various perioperative risk factors for pacemaker dependency and non-resolution of AV conduction disease, results have been inconsistent. Well-conducted studies using a uniform definition of pacemaker dependency might identify patients who will benefit most from early permanent pacemaker implantation after cardiac surgery. PMID:26470027

Assessment of Using 99Mo and 99mTc Isotopes in Kuwait Medical Sector.

PubMed

Ali, Naser

2016-04-01

The Ministry of Health (MOH) in the state of Kuwait currently depends on importing the radioisotope molybdenum (Mo) in its isotopic form (Mo) to fulfill its demands. The present study was conducted on all nuclear medicine departments in the state of Kuwait. Daily, weekly, and monthly data were analyzed to statistically determine the current and future demands for the isotope Tc. This analysis was performed by collecting and analyzing data on MOH consumption of Tc for different diagnostic applications. The overall results indicate a partial decrease of 1.012% in the overall total demand for Tc up to the year 2018 for the state of Kuwait.

Diagnosed, identified, current and complete depression among patients attending primary care in southern Catalonia: different aspects of the same concept.

PubMed

Montesó-Curto, Pilar; Ferré-Grau, Carme; Lleixà-Fortuño, Mar; Albacar-Riobóo, Nuria; Lejeune, Marylene

2014-02-01

The aims of this study were to explore the prevalence and the conceptualizations of depression detected by the healthcare system, identified by the patient or classified/identified in the validated Goldberg's questionnaire in a community. We conducted a cross-sectional evaluation of 317 patients. The different types of depression diagnosed, identified, current or total were stratified by age and gender groups. The difference in the conceptualization of depression from the medical or ordinary people point of view indicate that depression care requires the understanding of the lifestyle, beliefs, attitudes, family and social networks of the people the physicians and nurses care for. © 2014.

Comparison of current map data with data from STS-99 SRTM

NASA Image and Video Library

2000-02-04

JSC2000E01552 (January 2000) --- This chart compares currently available global map data with the data which will be provided by SRTM during STS-99. The area depicted is the California coast. The SRTM mission will have approximately 1,000 scheduled data takes (every time Endeavour is over land). Data acquisition will be conducted in excess of 80 hours. The recording rate for data will be 180 Mbits/sec for C-band, 90 Mbits/sec for X-band. Total raw radar data will be approximately 9.8 terabytes (15,000 CDs). The mission will utilize some 300 high-density tapes (each tape records 30 min. of C-band, or 60 min. of X-band data).

Characterization of SiO2/SiC interface states and channel mobility from MOSFET characteristics including variable-range hopping at cryogenic temperature

NASA Astrophysics Data System (ADS)

Yoshioka, Hironori; Hirata, Kazuto

2018-04-01

The characteristics of SiC MOSFETs (drain current vs. gate voltage) were measured at 0.14-350 K and analyzed considering variable-range hopping conduction through interface states. The total interface state density was determined to be 5.4×1012 cm-2 from the additional shift in the threshold gate voltage with a temperature change. The wave-function size of interface states was determined from the temperature dependence of the measured hopping current and was comparable to the theoretical value. The channel mobility was approximately 100 cm2V-1s-1 and was almost independent of temperature.

Comparative Analyses of Multi-Pulse Phase Controlled Rectifiers in Continuous Conduction Mode with a Two-Pole LC Output Filter for Surface Ship DC Applications

DTIC Science & Technology

2013-03-01

for this sub-mode, the minimum inductor current occurs at an angle 3 3t  (where 3 60    referenced to  ), as shown in Figure 13. 24...can be rewritten as    sin cos cosb b b ApA B      . (73) Grouping similar terms, yields  sin cosb b ApA B         , (74...where the fundamental frequency and each harmonic component are displayed graphically in a bar chart format as shown in Figure 25. The total current

Longitudinal gradient coil optimization in the presence of transient eddy currents.

PubMed

Trakic, A; Liu, F; Lopez, H Sanchez; Wang, H; Crozier, S

2007-06-01

The switching of magnetic field gradient coils in magnetic resonance imaging (MRI) inevitably induces transient eddy currents in conducting system components, such as the cryostat vessel. These secondary currents degrade the spatial and temporal performance of the gradient coils, and compensation methods are commonly employed to correct for these distortions. This theoretical study shows that by incorporating the eddy currents into the coil optimization process, it is possible to modify a gradient coil design so that the fields created by the coil and the eddy currents combine together to generate a spatially homogeneous gradient that follows the input pulse. Shielded and unshielded longitudinal gradient coils are used to exemplify this novel approach. To assist in the evaluation of transient eddy currents induced within a realistic cryostat vessel, a low-frequency finite-difference time-domain (FDTD) method using the total-field scattered-field (TFSF) scheme was performed. The simulations demonstrate the effectiveness of the proposed method for optimizing longitudinal gradient fields while taking into account the spatial and temporal behavior of the eddy currents.

Kinetic interpretation of resonance phenomena in low pressure capacitively coupled radio frequency plasmas

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

Wilczek, Sebastian; Trieschmann, Jan; Eremin, Denis

Low pressure capacitive radio frequency (RF) plasmas are often described by equivalent circuit models based on fluid approaches that predict the self-excitation of resonances, e.g., high frequency oscillations of the total current in asymmetric discharges, but do not provide a kinetic interpretation of these effects. In fact, they leave important questions open: How is current continuity ensured in the presence of energetic electron beams generated by the expanding sheaths that lead to a local enhancement of the conduction current propagating through the bulk? How do the beam electrons interact with cold bulk electrons? What is the kinetic origin of resonancemore » phenomena? Based on kinetic simulations, we find that the energetic beam electrons interact with cold bulk electrons (modulated on a timescale of the inverse local electron plasma frequency) via a time dependent electric field outside the sheaths. This electric field is caused by the electron beam itself, which leaves behind a positive space charge, that attracts cold bulk electrons towards the expanding sheath. The resulting displacement current ensures current continuity by locally compensating the enhancement of the conduction current. The backflow of cold electrons and their interaction with the nonlinear plasma sheath cause the generation of multiple electron beams during one phase of sheath expansion and contribute to a strongly non-sinusoidal RF current. These kinetic mechanisms are the basis for a fundamental understanding of the electron power absorption dynamics and resonance phenomena in such plasmas, which are found to occur in discharges of different symmetries including perfectly symmetric plasmas.« less

Biological Assessment to Support Ecological Recovery of a Degraded Headwater System

NASA Astrophysics Data System (ADS)

Longing, Scott D.; Haggard, Brian E.

2010-09-01

An assessment of the benthic macroinvertebrate community was conducted to characterize the ecological recovery of a channelized main stem and two small tributaries at the Watershed Research and Education Center (WREC, Arkansas, USA). Three other headwater streams in the same basin were also sampled as controls and for biological reference information. A principal components analysis produced stream groupings along an overall gradient of physical habitat integrity, with degraded reaches showing lower RBP habitat scores, reduced flow velocities, smaller substrate sizes, greater conductivity, and higher percentages of sand and silt substrate. The benthic macroinvertebrate assemblage at WREC was dominated by fast-reproducing dipteran larvae (midge and mosquito larvae) and physid snails, which comprised 71.3% of the total macroinvertebrate abundance over three sampling periods. Several macroinvertebrate assemblage metrics should provide effective targets for monitoring overall improvements in the invertebrate assemblage including recovery towards a more complex food web (e.g., total number of taxa, number of EPT taxa, percent 2 dominant taxa). However, current habitat conditions and the extent of existing degradation, system isolation and surrounding urban or agricultural land-uses might affect the level of positive change to the system. We therefore suggest a preliminary restoration strategy involving the addition of pool habitats in the system. At one pool we collected a total of 29 taxa (dominated by water beetle predators), which was 59% of total number of taxa collected at WREC. Maintaining water-retentive pools to collect flows and maintain water permanence focuses on enhancing known biology and habitat, thus reducing the effects of abiotic filters on macroinvertebrate assemblage recovery. Furthermore, biological assessment prior to restoration supports a strategy primarily focused on improving the existing macroinvertebrate community in the current context of the system, thereby reducing costs associated with active channel restoration. Monitoring future biological recovery and determining the contribution of changing assemblages to specific ecological processes would provide a critical underpinning for adaptive management and ecologically-effective restoration.

Corrigendum to "Characteristics of equatorial electrojet derived from Swarm satellites" [Adv. Space Res. 59 (2017) 1526-1538

NASA Astrophysics Data System (ADS)

Thomas, Neethal; Vichare, Geeta; Sinha, A. K.

2018-02-01

The authors regret that a typographical error in Abstract and Section 5 should be corrected. Figure 7b of Thomas et al. [2017] presents the variation of total westward return current (y-axis) with total eastward forward current (x-axis). The slopes vary between 1 and 0.1. This indicates that ratio of total westward return currents to total eastward forward current vary between 0.1 to 1. However in Abstract and Section 5, the authors have erroneously written the ratio as between "total eastward forward current to total westward return current".

Activity Patterns in Response to Symptoms in Patients Being Treated for Chronic Fatigue Syndrome: An Experience Sampling Methodology Study

PubMed Central

2016-01-01

Objective: Cognitive–behavioral models of chronic fatigue syndrome (CFS) propose that patients respond to symptoms with 2 predominant activity patterns—activity limitation and all-or-nothing behaviors—both of which may contribute to illness persistence. The current study investigated whether activity patterns occurred at the same time as, or followed on from, patient symptom experience and affect. Method: Twenty-three adults with CFS were recruited from U.K. CFS services. Experience sampling methodology (ESM) was used to assess fluctuations in patient symptom experience, affect, and activity management patterns over 10 assessments per day for a total of 6 days. Assessments were conducted within patients’ daily life and were delivered through an app on touchscreen Android mobile phones. Multilevel model analyses were conducted to examine the role of self-reported patient fatigue, pain, and affect as predictors of change in activity patterns at the same and subsequent assessment. Results: Current experience of fatigue-related symptoms and pain predicted higher patient activity limitation at the current and subsequent assessments whereas subjective wellness predicted higher all-or-nothing behavior at both times. Current pain predicted less all-or-nothing behavior at the subsequent assessment. In contrast to hypotheses, current positive affect was predictive of current activity limitation whereas current negative affect was predictive of current all-or-nothing behavior. Both activity patterns varied at the momentary level. Conclusions: Patient symptom experiences appear to be driving patient activity management patterns in line with the cognitive–behavioral model of CFS. ESM offers a useful method for examining multiple interacting variables within the context of patients’ daily life. PMID:27819461

Battery Cell Thermal Runaway Calorimeter

NASA Technical Reports Server (NTRS)

Darcy, Eric

2017-01-01

We currently have several methods for determining total energy output of an 18650 lithium ion cell. We do not, however, have a good method for determining the fraction of energy that dissipates via conduction through the cell can vs. the energy that is released in the form of ejecta. Knowledge of this fraction informs the design of our models, battery packs, and storage devices; (a) No longer need to assume cell stays together in modeling (b) Increase efficiency of TR mitigation (c) Shave off excess protection.

Cooperative Program Initiatives Survey. Results of a Nation-Wide Survey to Identify Existing and Planned Collaborative Training Programs for Allied Health and Education Professionals Serving Children with Handicapping Conditions (A Component of the Project "Training Alliances in Health and Education," 1983-1986).

ERIC Educational Resources Information Center

American Society of Allied Health Professions, Washington, DC.

In 1984, the American Society of Allied Health Professionals (ASAHP) conducted a mail survey of "Cooperative Program Initiatives"--seeking to identify current interdisciplinary training programs established to prepare both health and education professionals to meet the needs of youngsters with handicapping conditions and their families. A total of…

On optimal current patterns for electrical impedance tomography.

PubMed

Demidenko, Eugene; Hartov, Alex; Soni, Nirmal; Paulsen, Keith D

2005-02-01

We develop a statistical criterion for optimal patterns in planar circular electrical impedance tomography. These patterns minimize the total variance of the estimation for the resistance or conductance matrix. It is shown that trigonometric patterns (Isaacson, 1986), originally derived from the concept of distinguishability, are a special case of our optimal statistical patterns. New optimal random patterns are introduced. Recovering the electrical properties of the measured body is greatly simplified when optimal patterns are used. The Neumann-to-Dirichlet map and the optimal patterns are derived for a homogeneous medium with an arbitrary distribution of the electrodes on the periphery. As a special case, optimal patterns are developed for a practical EIT system with a finite number of electrodes. For a general nonhomogeneous medium, with no a priori restriction, the optimal patterns for the resistance and conductance matrix are the same. However, for a homogeneous medium, the best current pattern is the worst voltage pattern and vice versa. We study the effect of the number and the width of the electrodes on the estimate of resistivity and conductivity in a homogeneous medium. We confirm experimentally that the optimal patterns produce minimum conductivity variance in a homogeneous medium. Our statistical model is able to discriminate between a homogenous agar phantom and one with a 2 mm air hole with error probability (p-value) 1/1000.

Water Velocities and the Potential for the Movement of Bed Sediments in Sinclair Inlet of Puget Sound, Washington

USGS Publications Warehouse

Gartner, Jeffrey W.; Prych, E.A.; Tate, G.B.; Cacchione, D.A.; Cheng, R.T.; Bidlake, W.R.; Ferreira, J.T.

1998-01-01

Sinclair Inlet is a small embayment of Puget Sound in the State of Washington. The inlet, about 6.5 kilometers long and 1.5 kilometers wide, is the site of Puget Sound Naval Shipyard. There are concerns that bed sediments in the inlet may have been contaminated as a result of activities at the shipyard, and that these sediments could be resuspended by tide- and wind-driven currents and transported within the inlet or out of the inlet to other parts of Puget Sound. This study was conducted to provide information concerning the potential for sediment resuspension in the inlet. To obtain the necessary data, vertical profiles of water current from about 2 meters above the bed to 2 meters below the water surface were monitored with acoustic Doppler current profilers (ADCPs) at three locations during a 6.5-week winter period and a 4.5-week summer period in 1994. In addition, during the winter period, water velocites between 0.19 and 1.20 meters above the bed were measured with current meters using an instrument package called Geoprobe, which was deployed near one of the ADCPs. Other instruments on the Geoprobe measured light transmissivity, and a camera periodically took photographs of the bottom. Instruments on the Geoprobe and on the ADCPs also measured conductivity (for determining salinity), temperature, and pressure (for determinining tide). Samples of bed sediment and water samples for determining suspended-sediment concentration were collected at each of the current-measurement stations. Wind speed and direction were measured at three stations during a 12-month period, and tide was measured at one of these stations. Water currents measured at the three locations in Sinclair Inlet were relatively weak. Typical speeds were 5 to 10 centimeters per second, and the RMS (root-mean-square) speeds were less than 8 centimeters per second. Tidal and residual currents were of similar magnitude. Residual currents near the bottom typically were flowing in the opposite direction of the prevailing wind, while surface currents were in the same direction as the prevailing wind. During most of the year, the prevailing wind was from the soutwest quadrant; however, during July and August, the prevailing wind was usually from the northeast quadrant. The RMS of the total shear velocity for each ADCP station and measurement period, which was estimated from observed profiles of current velocity, ranged from 0.31 centimeters per second to 0.44 centimeters per second. The skin-friction component of the shear velocity was estimated to be no more than half the total. Critical shear velocity, estimated from particle sizes and density of the bed material, was 0.39 centimeters per second or larger. Comparisons of the skin-friction components of total bottom shear velocities with estimates of the critical shear velocity necessary for resuspension of the bed sediments indicate that resuspension occurs only infrequently, usually at times of maximum current during the tidal cycle. This conclusion is supported by measurements near the bed of light transmissivity, which is related to suspended-sediment concentration.

Phytochemical screening, total phenolic, total flavonoids contents and antioxidant activity of cinchona ledgeriana leaves ethanol extract

NASA Astrophysics Data System (ADS)

Sundowo, Andini; Artanti, Nina; Hanafi, M.; Minarti, Primahana, Gian

2017-11-01

C ledgeriana is a medicinal plant that contains alkaloids, especially on the barks for commercial production of quinine as antimalarial. The main alkaloids in this plant are cinchonine, cinchonidine, quinine and quinidine. Besides for antiamalarial this plant is also commonly used to treat whooping cough, influenza and dysentery. Compare to other medicinal plants, nowadays only very few studies were conducted in Cinchona species. Our current study aims to determine the content of phytochemical, total phenol and total flavonoids from C. ledgeriana leaves 70% ethanol extract. The extraction was performed by maceration method using 70% ethanol solvent and then fractionated into hexane, ethylacetate and butanol. Phytochemical screening was performed to determine the content of alkaloids, flavonoids, terpenoids, tannins and saponins. Total phenol and flavonoid contents of the extract were determined by Folin-Ciocalteu and alumunium chloride colorimetric methods using gallic acid and quercetin as standards. The antioxidant activity was determined by using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. The results of phytochemical screening showed that the 70% ethanol extract of C. ledgeriana leaves contained alkaloids, flavonoids, terpenoids, tannins and saponins. The total phenol and total flavonoids analysis showed that ethyl acetate fraction had the highest total phenol (40.23%) and total flavonoids (65.34%).

Pb, Hg, Cd, As, Sb and Al levels in foodstuffs from the 2nd French total diet study.

PubMed

Millour, Sandrine; Noël, Laurent; Kadar, Ali; Chekri, Rachida; Vastel, Christelle; Sirot, Véronique; Leblanc, Jean-Charles; Guérin, Thierry

2011-06-15

In 2006, the French Food Safety Agency (AFSSA) conducted the second French total diet study (TDS) to estimate dietary exposures of main minerals and trace elements from 1319 samples of foods habitually consumed by the French population. The foodstuffs were analysed by ICP-MS after microwave-assisted digestion. Contamination data for lead, mercury, cadmium, arsenic, antimony and aluminium were reported and compared with results from the previous French total diet study. The results are comparable with those from the rest of Europe. "Fish and fish products" and "sweeteners, honey and confectionery" were the food groups showing the highest cumulated contents in Pb, Hg, Cd, As, Al and Sb. However, observed levels remained low and were generally well below the maximum levels set by the current European regulation for lead, cadmium and mercury. Copyright © 2010 Elsevier Ltd. All rights reserved.

Software Toolbox for Low-Frequency Conductivity and Current Density Imaging Using MRI.

PubMed

Sajib, Saurav Z K; Katoch, Nitish; Kim, Hyung Joong; Kwon, Oh In; Woo, Eung Je

2017-11-01

Low-frequency conductivity and current density imaging using MRI includes magnetic resonance electrical impedance tomography (MREIT), diffusion tensor MREIT (DT-MREIT), conductivity tensor imaging (CTI), and magnetic resonance current density imaging (MRCDI). MRCDI and MREIT provide current density and isotropic conductivity images, respectively, using current-injection phase MRI techniques. DT-MREIT produces anisotropic conductivity tensor images by incorporating diffusion weighted MRI into MREIT. These current-injection techniques are finding clinical applications in diagnostic imaging and also in transcranial direct current stimulation (tDCS), deep brain stimulation (DBS), and electroporation where treatment currents can function as imaging currents. To avoid adverse effects of nerve and muscle stimulations due to injected currents, conductivity tensor imaging (CTI) utilizes B1 mapping and multi-b diffusion weighted MRI to produce low-frequency anisotropic conductivity tensor images without injecting current. This paper describes numerical implementations of several key mathematical functions for conductivity and current density image reconstructions in MRCDI, MREIT, DT-MREIT, and CTI. To facilitate experimental studies of clinical applications, we developed a software toolbox for these low-frequency conductivity and current density imaging methods. This MR-based conductivity imaging (MRCI) toolbox includes 11 toolbox functions which can be used in the MATLAB environment. The MRCI toolbox is available at http://iirc.khu.ac.kr/software.html . Its functions were tested by using several experimental datasets, which are provided together with the toolbox. Users of the toolbox can focus on experimental designs and interpretations of reconstructed images instead of developing their own image reconstruction softwares. We expect more toolbox functions to be added from future research outcomes. Low-frequency conductivity and current density imaging using MRI includes magnetic resonance electrical impedance tomography (MREIT), diffusion tensor MREIT (DT-MREIT), conductivity tensor imaging (CTI), and magnetic resonance current density imaging (MRCDI). MRCDI and MREIT provide current density and isotropic conductivity images, respectively, using current-injection phase MRI techniques. DT-MREIT produces anisotropic conductivity tensor images by incorporating diffusion weighted MRI into MREIT. These current-injection techniques are finding clinical applications in diagnostic imaging and also in transcranial direct current stimulation (tDCS), deep brain stimulation (DBS), and electroporation where treatment currents can function as imaging currents. To avoid adverse effects of nerve and muscle stimulations due to injected currents, conductivity tensor imaging (CTI) utilizes B1 mapping and multi-b diffusion weighted MRI to produce low-frequency anisotropic conductivity tensor images without injecting current. This paper describes numerical implementations of several key mathematical functions for conductivity and current density image reconstructions in MRCDI, MREIT, DT-MREIT, and CTI. To facilitate experimental studies of clinical applications, we developed a software toolbox for these low-frequency conductivity and current density imaging methods. This MR-based conductivity imaging (MRCI) toolbox includes 11 toolbox functions which can be used in the MATLAB environment. The MRCI toolbox is available at http://iirc.khu.ac.kr/software.html . Its functions were tested by using several experimental datasets, which are provided together with the toolbox. Users of the toolbox can focus on experimental designs and interpretations of reconstructed images instead of developing their own image reconstruction softwares. We expect more toolbox functions to be added from future research outcomes.

Gen 2.0 Mixer/Ejector Nozzle Test at LSAF June 1995 to July 1996

NASA Technical Reports Server (NTRS)

Arney, L. D.; Sandquist, D. L.; Forsyth, D. W.; Lidstone, G. L.; Long-Davis, Mary Jo (Technical Monitor)

2005-01-01

Testing of the HSCT Generation 2.0 nozzle model hardware was conducted at the Boeing Low Speed Aeroacoustic Facility, LSAF. Concurrent measurements of noise and thrust were made at critical takeoff design conditions for a variety of mixer/ejector model hardware. Design variables such as suppressor area ratio, mixer area ratio, liner type and thickness, ejector length, lobe penetration, and mixer chute shape were tested. Parallel testing was conducted at G.E.'s Cell 41 acoustic free jet facility to augment the LSAF test. The results from the Gen 2.0 testing are being used to help shape the current nozzle baseline configuration and guide the efforts in the upcoming Generation 2.5 and 3.0 nozzle tests. The Gen 2.0 results have been included in the total airplane system studies conducted at MDC and Boeing to provide updated noise and thrust performance estimates.

Grain-scale supercharging and breakdown on airless regoliths

NASA Astrophysics Data System (ADS)

Zimmerman, M. I.; Farrell, W. M.; Hartzell, C. M.; Wang, X.; Horanyi, M.; Hurley, D. M.; Hibbitts, K.

2016-10-01

Interactions of the solar wind and emitted photoelectrons with airless bodies have been studied extensively. However, the details of how charged particles interact with the regolith at the scale of a single grain have remained largely uncharacterized. Recent efforts have focused upon determining total surface charge under photoemission and solar wind bombardment and the associated electric field and potential. In this work, theory and simulations are used to show that grain-grain charge differences can exceed classical sheath predictions by several orders of magnitude, sometimes reaching dielectric breakdown levels. Temperature-dependent electrical conductivity works against supercharging by allowing current to leak through individual grains; the balance between internal conduction and surface charging controls the maximum possible grain-to-grain electric field. Understanding the finer details of regolith grain charging, conductive equilibrium, and dielectric breakdown will improve future numerical studies of space weathering and dust levitation on airless bodies.

Magnetic modulation of inverse spin Hall effect in lateral spin-valves

NASA Astrophysics Data System (ADS)

Andrianov, T.; Vedyaev, A.; Dieny, B.

2018-05-01

We analytically investigated the spin-dependent transport properties in a lateral spin-valve device comprising pinned ferromagnetic electrodes allowing the injection of a spin current in a spin conducting channel where spin orbit scattering takes place. This produces an inverse spin Hall (ISHE) voltage across the thickness of the spin conducting channel. It is shown that by adding an extra soft ferromagnetic electrode with rotatable magnetization along the spin conducting channel, the ISHE generated voltage can be magnetically modulated by changing the magnetization orientation of this additional electrode. The dependence of the ISHE voltage on the direction of magnetization of the ferromagnetic electrode with rotatable magnetization was calculated in various configurations. Our results suggest that such structures could be considered as magnetic field sensors in situations where the total thickness of the sensor is constrained such as in hard disk drive readers.

Grain-Scale Supercharging and Breakdown on Airless Regoliths

NASA Technical Reports Server (NTRS)

Zimmerman, M. I.; Farrell, W. M.; Hartzell, C.M.; Wang, X.; Horanyi, M.; Hurley, D. M.; Hibbitts, K.

2016-01-01

Interactions of the solar wind and emitted photoelectrons with airless bodies have been studied extensively. However, the details of how charged particles interact with the regolith at the scale of a single grain have remained largely uncharacterized. Recent efforts have focused upon determining total surface charge under photoemission and solar wind bombardment and the associated electric field and potential. In this work, theory and simulations are used to show that grain-grain charge differences can exceed classical sheath predictions by several orders of magnitude, sometimes reaching dielectric breakdown levels. Temperature-dependent electrical conductivity works against supercharging by allowing current to leak through individual grains; the balance between internal conduction and surface charging controls the maximum possible grain-to-grain electric field. Understanding the finer details of regolith grain charging, conductive equilibrium, and dielectric breakdown will improve future numerical studies of space weathering and dust levitation on airless bodies.

Historic and current use of Lower Cook Inlet, Alaska, by Belugas, Delphinapterus leucas

USGS Publications Warehouse

Speckman, Suzann G.; Piatt, John F.

2000-01-01

Dedicated at-sea surveys for marine birds and mammals conducted in lower Cook Inlet in late July and early August from 1995–99 failed to locate any belugas, Delphinapterus leucas. Surveys covered a total of 6,249 linear km and were conducted in both nearshore and offshore habitats. Sightings included 791 individual marine mammals of 10 species. Both historical data and local knowledge indicate that belugas were regularly seen in summer in nearshore and offshore areas of lower Cook Inlet up until the early 1990’s. Diminished presence of belugas in lower Cook Inlet may be a direct function of reduced numbers but may also indicate changes in habitat quality that may inhibit recovery.

Development of Tissue to Total Mass Correction Factor for Porites divaricata in Calcification Rate Studies

NASA Astrophysics Data System (ADS)

Cannone, T. C.; Kelly, S. K.; Foster, K.

2013-05-01

One anticipated result of ocean acidification is lower calcification rates of corals. Many studies currently use the buoyant weights of coral nubbins as a means of estimating skeletal weight during non-destructive experiments. The objectives of this study, conducted at the Little Cayman Research Centre, were twofold: (1) to determine whether the purple and yellow color variations of Porites divaricata had similar tissue mass to total mass ratios; and (2) to determine a correction factor for tissue mass based on the total coral mass. T-test comparisons indicated that the tissue to total mass ratios were statistically similar for purple and yellow cohorts, thus allowing them to be grouped together within a given sample population. Linear regression analysis provided a correction factor (r2 = 0.69) to estimate the tissue mass from the total mass, which may eliminate the need to remove tissue during studies and allow subsequent testing on the same nubbins or their return to the natural environment. Additional work is needed in the development of a correction factor for P. divaricata with a higher prediction accuracy.

Method and apparatus for casting conductive and semi-conductive materials

DOEpatents

Ciszek, T.F.

1984-08-13

A method and apparatus is disclosed for casting conductive and semi-conductive materials. The apparatus includes a plurality of conductive members arranged to define a container-like area having a desired cross-sectional shape. A portion or all of the conductive or semi-conductive material which is to be cast is introduced into the container-like area. A means is provided for inducing the flow of an electrical current in each of the conductive members, which currents act collectively to induce a current flow in the material. The induced current flow through the conductive members is in a direction substantially opposite to the induced current flow in the material so that the material is repelled from the conductive members during the casting process.

Transient Response in a Dendritic Neuron Model for Current Injected at One Branch

PubMed Central

Rinzel, John; Rall, Wilfrid

1974-01-01

Mathematical expressions are obtained for the response function corresponding to an instantaneous pulse of current injected to a single dendritic branch in a branched dendritic neuron model. The theoretical model assumes passive membrane properties and the equivalent cylinder constraint on branch diameters. The response function when used in a convolution formula enables one to compute the voltage transient at any specified point in the dendritic tree for an arbitrary current injection at a given input location. A particular numerical example, for a brief current injection at a branch terminal, illustrates the attenuation and delay characteristics of the depolarization peak as it spreads throughout the neuron model. In contrast to the severe attenuation of voltage transients from branch input sites to the soma, the fraction of total input charge actually delivered to the soma and other trees is calculated to be about one-half. This fraction is independent of the input time course. Other numerical examples, which compare a branch terminal input site with a soma input site, demonstrate that, for a given transient current injection, the peak depolarization is not proportional to the input resistance at the injection site and, for a given synaptic conductance transient, the effective synaptic driving potential can be significantly reduced, resulting in less synaptic current flow and charge, for a branch input site. Also, for the synaptic case, the two inputs are compared on the basis of the excitatory post-synaptic potential (EPSP) seen at the soma and the total charge delivered to the soma. PMID:4424185

Electron-induced electron yields of uncharged insulating materials

NASA Astrophysics Data System (ADS)

Hoffmann, Ryan Carl

Presented here are electron-induced electron yield measurements from high-resistivity, high-yield materials to support a model for the yield of uncharged insulators. These measurements are made using a low-fluence, pulsed electron beam and charge neutralization to minimize charge accumulation. They show charging induced changes in the total yield, as much as 75%, even for incident electron fluences of <3 fC/mm2, when compared to an uncharged yield. The evolution of the yield as charge accumulates in the material is described in terms of electron recapture, based on the extended Chung and Everhart model of the electron emission spectrum and the dual dynamic layer model for internal charge distribution. This model is used to explain charge-induced total yield modification measured in high-yield ceramics, and to provide a method for determining electron yield of uncharged, highly insulating, high-yield materials. A sequence of materials with progressively greater charge susceptibility is presented. This series starts with low-yield Kapton derivative called CP1, then considers a moderate-yield material, Kapton HN, and ends with a high-yield ceramic, polycrystalline aluminum oxide. Applicability of conductivity (both radiation induced conductivity (RIC) and dark current conductivity) to the yield is addressed. Relevance of these results to spacecraft charging is also discussed.

Incidence of First Time Stroke: A Saudi Experience.

PubMed

Al-Shenqiti, Abdullah M; Ibrahim, Sameh R; Khaled, Osama A; Ali, Abdul Rahman H; Ahmed, Mostafa S

2017-01-01

Stroke is one of the major causes of morbidity and mortality throughout the world. A number of studies were conducted in Saudi Arabia. However, there were no studies conducted in Al-Madinah Al-Munawarah city. The aim of this study was to ascertain the incidence rate of first time stroke and the age-specific incidence in both genders in Al-Madinah Al-Munawarah city. A prospective hospital based study was conducted over a 1-year period (2014). The cases were included in the study when they were admitted with a diagnosis of cerebrovascular accident. A total 164 patients (91 men and 73 women) who had first time stroke were found in this study with no significant difference between them (p = 0.565). The crude incidence rate of stroke was 13.89 per 100,000 persons. The age-specific incidence rate increased with age in the current study, where the peak was in the age group of more than 75 years old for men and women. Total crude and the age-specific rates for first time stroke patients revealed in this study were markedly lower than the range reported from the developed countries. However, they were within the range that showed previously in Saudi Arabia and Arabian Peninsula countries. © 2017 S. Karger AG, Basel.

Dendritic excitability modulates dendritic information processing in a purkinje cell model.

PubMed

Coop, Allan D; Cornelis, Hugo; Santamaria, Fidel

2010-01-01

Using an electrophysiological compartmental model of a Purkinje cell we quantified the contribution of individual active dendritic currents to processing of synaptic activity from granule cells. We used mutual information as a measure to quantify the information from the total excitatory input current (I(Glu)) encoded in each dendritic current. In this context, each active current was considered an information channel. Our analyses showed that most of the information was encoded by the calcium (I(CaP)) and calcium activated potassium (I(Kc)) currents. Mutual information between I(Glu) and I(CaP) and I(Kc) was sensitive to different levels of excitatory and inhibitory synaptic activity that, at the same time, resulted in the same firing rate at the soma. Since dendritic excitability could be a mechanism to regulate information processing in neurons we quantified the changes in mutual information between I(Glu) and all Purkinje cell currents as a function of the density of dendritic Ca (g(CaP)) and Kca (g(Kc)) conductances. We extended our analysis to determine the window of temporal integration of I(Glu) by I(CaP) and I(Kc) as a function of channel density and synaptic activity. The window of information integration has a stronger dependence on increasing values of g(Kc) than on g(CaP), but at high levels of synaptic stimulation information integration is reduced to a few milliseconds. Overall, our results show that different dendritic conductances differentially encode synaptic activity and that dendritic excitability and the level of synaptic activity regulate the flow of information in dendrites.

An analytic current-voltage model for quasi-ballistic III-nitride high electron mobility transistors

NASA Astrophysics Data System (ADS)

Li, Kexin; Rakheja, Shaloo

2018-05-01

We present an analytic model to describe the DC current-voltage (I-V) relationship in scaled III-nitride high electron mobility transistors (HEMTs) in which transport within the channel is quasi-ballistic in nature. Following Landauer's transport theory and charge calculation based on two-dimensional electrostatics that incorporates negative momenta states from the drain terminal, an analytic expression for current as a function of terminal voltages is developed. The model interprets the non-linearity of access regions in non-self-aligned HEMTs. Effects of Joule heating with temperature-dependent thermal conductivity are incorporated in the model in a self-consistent manner. With a total of 26 input parameters, the analytic model offers reduced empiricism compared to existing GaN HEMT models. To verify the model, experimental I-V data of InAlN/GaN with InGaN back-barrier HEMTs with channel lengths of 42 and 105 nm are considered. Additionally, the model is validated against numerical I-V data obtained from DC hydrodynamic simulations of an unintentionally doped AlGaN-on-GaN HEMT with 50-nm gate length. The model is also verified against pulsed I-V measurements of a 150-nm T-gate GaN HEMT. Excellent agreement between the model and experimental and numerical results for output current, transconductance, and output conductance is demonstrated over a broad range of bias and temperature conditions.

Treatment and toxicity reduction of textile dyeing wastewater using the electrocoagulation-electroflotation process.

PubMed

Kim, Han-Lae; Cho, Jong-Bok; Park, Yong-Jin; Cho, Il-Hyoung

2016-07-02

A pilot-scale study was conducted using the electrocoagulation-electroflotation (EC-EF) process to treat textile dyeing raw wastewater to evaluate treatment performance. The effects of some key factors, such as current density, hydraulic retention time (HRT), and removal of conductivity, total suspended solids (TSS), chemical oxygen demand (COD), and color were investigated. The operating variables were current density of 0-300 A m(-2), HRT of 0-30 min, and a coagulant (anionic polyacrylamide (A-PAM)) dosage of 0-30 mg L(-1). Daphnia magna was used to test acute toxicity in raw and treated wastewater. Under the operating conditions without added coagulant, maxima of 51%, 88%, 84%, and 99% of conductivity, TSS, COD, and color were removed, respectively, with a HRT of 30 min. The coagulant enhanced removal of all wastewater parameters. Removal maxima of 59%, 92%, 94%, and 98% for conductivity, TSS, COD, and color were observed, respectively, with an optimal dosage of 30 mg L(-1) and a shortened HRT of 20 min. The 48 h-LC50 D. magna test showed that the raw wastewater was highly toxic. However, the EC-EF process decreased toxicity of the treated samples significantly, and >70% toxicity reduction was achieved by the EC-EF process with the addition of 15-30 mg L(-1) coagulant, HRT of 20 min, and current density of 150-300 A m(-2). The pilot scale test (0.3 m(3 )h(-1)) shows that the EC-EF process with added coagulant effectively treated textile dyeing wastewater.

Ambient iron-mediated aeration (IMA) for water reuse.

PubMed

Deng, Yang; Englehardt, James D; Abdul-Aziz, Samer; Bataille, Tristan; Cueto, Josenrique; De Leon, Omar; Wright, Mary E; Gardinali, Piero; Narayanan, Aarthi; Polar, Jose; Tomoyuki, Shibata

2013-02-01

Global water shortages caused by rapidly expanding population, escalating water consumption, and dwindling water reserves have rendered water reuse a strategically significant approach to meet current and future water demand. This study is the first to our knowledge to evaluate the technical feasibility of iron-mediated aeration (IMA), an innovative, potentially economical, holistic, oxidizing co-precipitation process operating at room temperature, atmospheric pressure, and neutral pH, for water reuse. In the IMA process, dissolved oxygen (O₂) was continuously activated by zero-valent iron (Fe⁰) to produce reactive oxygen species (ROS) at ambient pH, temperature, and pressure. Concurrently, iron sludge was generated as a result of iron corrosion. Bench-scale tests were conducted to study the performance of IMA for treatment of secondary effluent, natural surface water, and simulated contaminated water. The following removal efficiencies were achieved: 82.2% glyoxylic acid, ~100% formaldehyde as an oxidation product of glyoxylic acid, 94% of Ca²⁺ and associated alkalinity, 44% of chemical oxygen demand (COD), 26% of electrical conductivity (EC), 98% of di-n-butyl phthalate (DBP), 80% of 17β-estradiol (E2), 45% of total nitrogen (TN), 96% of total phosphorus (TP), 99.8% of total Cr, >90% of total Ni, 99% of color, 3.2 log removal of total coliform, and 2.4 log removal of E. Coli. Removal was attributed principally to chemical oxidation, precipitation, co-precipitation, coagulation, adsorption, and air stripping concurrently occurring during the IMA treatment. Results suggest that IMA is a promising treatment technology for water reuse. Copyright © 2012 Elsevier Ltd. All rights reserved.

Performance Characteristics of the NEXT Long-Duration Test After 16,550 h and 337 kg of Xenon Processed

NASA Technical Reports Server (NTRS)

Soulas, George C.; Patterson, Michael J.; Herman, Daniel A.

2009-01-01

The NASA s Evolutionary Xenon Thruster (NEXT) program is developing the next-generation ion propulsion system with significant enhancements beyond the state-of-the-art in ion propulsion to provide future NASA science missions with enhanced mission capabilities at a low total development cost. As part of a comprehensive thruster service life assessment utilizing both testing and analyses, a Long-Duration Test (LDT) was initiated to verify the NEXT propellant throughput capability to a qualification-level of 450 kg, 1.5 times the anticipated throughput requirement of 300 kg from mission analyses conducted utilizing the NEXT propulsion system. The LDT is being conducted with a modified, flight-representative NEXT engineering model ion thruster, designated EM3. As of June 25, 2008, the thruster has accumulated 16,550 h of operation: the first 13,042 h at the thruster full-input-power of 6.9 kW with 3.52 A beam current and 1800 V beam power supply voltage. Operation since 13,042 h, i.e., the most recent 3,508 h, has been at an input power of 4.7 kW with 3.52 A beam current and 1180 V beam power supply voltage. The thruster has processed 337 kg of xenon (Xe) surpassing the NSTAR propellant throughput demonstrated during the extended life testing of the Deep Space 1 flight spare ion thruster. The NEXT LDT has demonstrated a total impulse of 13.3 106 N s; the highest total impulse ever demonstrated by an ion thruster. Thruster performance tests are conducted periodically over the entire NEXT throttle table with input power ranging 0.5 to 6.9 kW. Thruster performance parameters including thrust, input power, specific impulse, and thruster efficiency have been nominal with little variation to date. This paper presents the performance of the NEXT LDT to date with emphasis on performance variations following throttling of the thruster to the new operating condition and comparison of performance to the NSTAR extended life test.

Novel CLCNKB mutations causing Bartter syndrome affect channel surface expression.

PubMed

Keck, Mathilde; Andrini, Olga; Lahuna, Olivier; Burgos, Johanna; Cid, L Pablo; Sepúlveda, Francisco V; L'hoste, Sébastien; Blanchard, Anne; Vargas-Poussou, Rosa; Lourdel, Stéphane; Teulon, Jacques

2013-09-01

Mutations in the CLCNKB gene encoding the ClC-Kb Cl(-) channel cause Bartter syndrome, which is a salt-losing renal tubulopathy. Here, we investigate the functional consequences of seven mutations. When expressed in Xenopus laevis oocytes, four mutants carried no current (c.736G>C, p.Gly246Arg; c.1271G>A, p.Gly424Glu; c.1313G>A, p.Arg438His; c.1316T>C, p.Leu439Pro), whereas others displayed a 30%-60% reduction in conductance as compared with wild-type ClC-Kb (c.242T>C, p.Leu81Pro; c.274C>T, p.Arg92Trp; c.1052G>C, p.Arg351Pro). Anion selectivity and sensitivity to external Ca(2+) and H(+), typical of the ClC-Kb channel, were not modified in the partially active mutants. In oocytes, we found that all the mutations reduced surface expression with a profile similar to that observed for currents. In HEK293 cells, the currents in the mutants had similar profiles to those obtained in oocytes, except for p.Leu81Pro, which produced no current. Furthermore, p.Arg92Trp and p.Arg351Pro mutations did not modify the unit-conductance of closely related ClC-K1. Western blot analysis in HEK293 cells showed that ClC-Kb protein abundance was lower for the nonconducting mutants but similar to wild-type for other mutants. Overall, two classes of mutants can be distinguished: nonconducting mutants associated with low total protein expression, and partially conducting mutants with unaltered channel properties and ClC-Kb protein abundance. © 2013 WILEY PERIODICALS, INC.

A QR accelerated volume-to-surface boundary condition for finite element solution of eddy current problems

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

White, D; Fasenfest, B; Rieben, R

2006-09-08

We are concerned with the solution of time-dependent electromagnetic eddy current problems using a finite element formulation on three-dimensional unstructured meshes. We allow for multiple conducting regions, and our goal is to develop an efficient computational method that does not require a computational mesh of the air/vacuum regions. This requires a sophisticated global boundary condition specifying the total fields on the conductor boundaries. We propose a Biot-Savart law based volume-to-surface boundary condition to meet this requirement. This Biot-Savart approach is demonstrated to be very accurate. In addition, this approach can be accelerated via a low-rank QR approximation of the discretizedmore » Biot-Savart law.« less

Performance Evaluation of 40 cm Ion Optics for the NEXT Ion Engine

NASA Technical Reports Server (NTRS)

Soulas, George C.; Haag, Thomas W.; Patterson, Michael J.

2002-01-01

The results of performance tests with two 40 cm ion optics sets are presented and compared to those of 30 cm ion optics with similar aperture geometries. The 40 cm ion optics utilized both NSTAR and TAG (Thick-Accelerator-Grid) aperture geometries. All 40 cm ion optics tests were conducted on a NEXT (NASA's Evolutionary Xenon Thruster) laboratory model ion engine. Ion optics performance tests were conducted over a beam current range of 1.20 to 3.52 A and an engine input power range of 1.1 to 6.9 kW. Measured ion optics' performance parameters included near-field radial beam current density profiles, impingement-limited total voltages, electron backstreaming limits, screen grid ion transparencies, beam divergence angles, and start-up transients. Impingement-limited total voltages for 40 cm ion optics with the NSTAR aperture geometry were 60 to 90 V lower than those with the TAG aperture geometry. This difference was speculated to be due to an incomplete burn-in of the TAG ion optics. Electron backstreaming limits for the 40 cm ion optics with the TAG aperture geometry were 8 to 19 V higher than those with the NSTAR aperture geometry due to the thicker accelerator grid of the TAG geometry. Because the NEXT ion engine provided beam flatness parameters that were 40 to 63 percent higher than those of the NSTAR ion engine, the 40 cm ion optics outperformed the 30 cm ion optics.

Style preference survey: a report on the psychometric properties and a cross-validation experiment.

PubMed

Smith, Sherri L; Ricketts, Todd; McArdle, Rachel A; Chisolm, Theresa H; Alexander, Genevieve; Bratt, Gene

2013-02-01

Several self-report measures exist that target different aspects of outcomes for hearing aid use. Currently, no comprehensive questionnaire specifically assesses factors that may be important for differentiating outcomes pertaining to hearing aid style. The goal of this work was to develop the Style Preference Survey (SPS), a questionnaire aimed at outcomes associated with hearing aid style differences. Two experiments were conducted. After initial item development, Experiment 1 was conducted to refine the items and to determine its psychometric properties. Experiment 2 was designed to cross-validate the findings from the initial experiment. An observational design was used in both experiments. Participants who wore traditional, custom-fitted (TC) or open-canal (OC) style hearing aids from 3 mo to 3 yr completed the initial experiment. One-hundred and eighty-four binaural hearing aid users (120 of whom wore TC hearing aids and 64 of whom wore OC hearing aids) participated. A new sample of TC and OC users (n = 185) participated in the cross-validation experiment. Currently available self-report measures were reviewed to identify items that might differentiate between hearing aid styles, particularly preference for OC versus TC hearing aid styles. A total of 15 items were selected and modified from available self-report measures. An additional 55 items were developed through consensus of six audiologists for the initial version of the SPS. In the first experiment, the initial SPS version was mailed to 550 veterans who met the inclusion criteria. A total of 184 completed the SPS. Approximately three weeks later, a subset of participants (n = 83) completed the SPS a second time. Basic analyses were conducted to evaluate the psychometric properties of the SPS including subscale structure, internal consistency, test-retest reliability, and responsiveness. Based on the results of Experiment 1, the SPS was revised. A cross-validation experiment was then conducted using the revised version of the SPS to confirm the subscale structure, internal consistency, and responsiveness of the questionnaire in a new sample of participants. The final factor analysis led to the ultimate version of the SPS, which had a total of 35 items encompassing five subscales: (1) Feedback, (2) Occlusion/Own Voice Effects, (3) Localization, (4) Fit, Comfort, and Cosmetics, and (5) Ease of Use. The internal consistency of the total SPS (Cronbach's α = .92) and of the subscales (each Cronbach's α > .75) was high. Intraclass correlations (ICCs) showed that the test-retest reliability of the total SPS (ICC = .93) and of the subscales (each ICC > .80) also was high. TC hearing aid users had significantly poorer outcomes than OC hearing aid users on 4 of the 5 subscales, suggesting that the SPS largely is responsive to factors related to style-specific differences. The results suggest that the SPS has good psychometric properties and is a valid and reliable measure of outcomes related to style-specific, hearing aid preference. American Academy of Audiology.

Diabetes and Cognitive Deficits in Chronic Schizophrenia: A Case-Control Study

PubMed Central

Han, Mei; Huang, Xu-Feng; Chen, Da Chun; Xiu, Meihong; Kosten, Thomas R.; Zhang, Xiang Yang

2013-01-01

Cognitive impairment occurs in both schizophrenia and diabetes. There is currently limited understanding whether schizophrenia with diabetes has more serious cognitive deficits than schizophrenia without diabetes or diabetes only. This study assessed cognitive performance in 190 healthy controls, 106 diabetes only, 127 schizophrenia without diabetes and 55 schizophrenia with diabetes. This study was conducted from January 2008 to December 2010. Compared to healthy controls, all patient groups had significantly decreased total and five index RBANS scores (all p<0.01–p<0.001), except for the visuospatial/constructional index. Schizophrenia with diabetes performed worse than schizophrenia without diabetes in immediate memory (p<0.01) and total RBANS scores (<0.05), and showed a trend for decreased attention (p = 0.052) and visuospatial/constructional capacity (p = 0.063). Schizophrenia with diabetes performed worse than diabetes only in immediate memory (p<0.001) and attention (p<0.05), and showed a trend for decreased total RBANS scores (p = 0.069). Regression analysis showed that the RBANS had modest correlations with schizophrenia’ PANSS scores, their duration of current antipsychotic treatment, and diagnosis of diabetes. Schizophrenia with co-morbid diabetes showed more cognitive impairment than schizophrenia without diabetes and diabetes only, especially in immediate memory and attention. PMID:23840437

Refined beam measurements on the SNS H- injector

NASA Astrophysics Data System (ADS)

Han, B. X.; Welton, R. F.; Murray, S. N.; Pennisi, T. R.; Santana, M.; Stinson, C. M.; Stockli, M. P.

2017-08-01

The H- injector for the SNS RFQ accelerator consists of an RF-driven, Cs-enhanced H- ion source and a compact, two-lens electrostatic LEBT. The LEBT output and the RFQ input beam current are measured by deflecting the beam on to an annular plate at the RFQ entrance. Our method and procedure have recently been refined to improve the measurement reliability and accuracy. The new measurements suggest that earlier measurements tended to underestimate the currents by 0-2 mA, but essentially confirm H- beam currents of 50-60 mA being injected into the RFQ. Emittance measurements conducted on a test stand featuring essentially the same H- injector setup show that the normalized rms emittance with 0.5% threshold (99% inclusion of the total beam) is in a range of 0.25-0.4 mm.mrad for a 50-60 mA beam. The RFQ output current is monitored with a BCM toroid. Measurements as well as simulations with the PARMTEQ code indicate an underperforming transmission of the RFQ since around 2012.

Wide-band current preamplifier for conductance measurements with large input capacitance.

PubMed

Kretinin, Andrey V; Chung, Yunchul

2012-08-01

A wide-band current preamplifier based on a composite operational amplifier is proposed. It has been shown that the bandwidth of the preamplifier can be significantly increased by enhancing the effective open-loop gain. The described 10(7) V/A current gain preamplifier had the bandwidth of about 100 kHz with the 1 nF input shunt capacitance. The measured preamplifier current noise was 46 fA/√Hz at 1 kHz, close to the design noise minimum. The voltage noise was found to be about 2.9 nV/√Hz at 1 kHz, which is in a good agreement with the value expected for the particular operational amplifier used in the input stage. By analysing the total produced noise we found that the optimal frequency range suitable for the fast lock-in measurements is from 1 kHz to 2 kHz. To obtain the same signal-to-noise ratio, the reported preamplifier requires ~10% of the integration time needed in measurements made with a conventional preamplifier.

The Evolution of a Long-Lived Mesoscale Convective System Observed by GLM

NASA Astrophysics Data System (ADS)

Peterson, M. J.; Rudlosky, S. D.; Antunes, L.

2017-12-01

Continuous Geostationary Lightning Mapper (GLM) observations are used to document total lightning activity over the life cycle of a long-lived Mesoscale Convective System (MCS). MCS's may be few in number, but they are important for the Global Electric Circuit (GEC) because they sustain high lightning flash rates and quasi steady state conduction currents (Wilson currents) over longer time periods than ordinary isolated convection. The optical characteristics of the flashes produced by MCS's change over time, providing additional insights into the precipitation structure, convective mode, and evolution of the storm system. These insights are particularly useful in areas void of radar observations. Intercalibrated passive microwave radiometer data from the Global Precipitation Measurement (GPM) constellation also are used to estimate changes in Wilson current generation as the system evolves. These results highlight the role of MCS's in the GEC, and showcase how optical flash descriptors relate to thunderstorm organization, maturity, and structure.

Scanning gate imaging of two coupled quantum dots in single-walled carbon nanotubes.

PubMed

Zhou, Xin; Hedberg, James; Miyahara, Yoichi; Grutter, Peter; Ishibashi, Koji

2014-12-12

Two coupled single wall carbon nanotube quantum dots in a multiple quantum dot system were characterized by using a low temperature scanning gate microscopy (SGM) technique, at a temperature of 170 mK. The locations of single wall carbon nanotube quantum dots were identified by taking the conductance images of a single wall carbon nanotube contacted by two metallic electrodes. The single electron transport through single wall carbon nanotube multiple quantum dots has been observed by varying either the position or voltage bias of a conductive atomic force microscopy tip. Clear hexagonal patterns were observed in the region of the conductance images where only two sets of overlapping conductance rings are visible. The values of coupling capacitance over the total capacitance of the two dots, C(m)/C(1(2)) have been extracted to be 0.21 ∼ 0.27 and 0.23 ∼ 0.28, respectively. In addition, the interdot coupling (conductance peak splitting) has also been confirmed in both conductance image measurement and current-voltage curves. The results show that a SGM technique enables spectroscopic investigation of coupled quantum dots even in the presence of unexpected multiple quantum dots.

Conductivity enhancement of carbon aerogel by modified gelation using self additive

NASA Astrophysics Data System (ADS)

Singh, Ashish; Kohli, D. K.; Bhartiya, Sushmita; Singh, Rashmi; Rajak, Gaurav; Singh, M. K.; Karnal, A. K.

2018-04-01

Carbon aerogels having high surface area and open pore structure are being studied for many electrochemical applications such as fuel cells and super capacitors. Moderate electrical conductivity of resorcinol - formaldehyde (R-F) derived carbon aerogel limits its utility in these applications. The current manuscript briefs about the synthesis of composite carbon aerogel using carbon aerogel itself as additive during gelation of water based carbon aerogel and study the effect on its conductivity and surface properties. The additive carbon aerogel was synthesized and pre-treated at higher temperature to achieve enhancement in conductivity. The composite carbon aerogel (CCA) samples were characterized for surface area properties, morphology, electrical conductivity and specific capacitance. The surface area properties of CCA showed improvement and specific surface area of ˜1798 m2/g with total pore volume of 1.7 cm3/g. was obtained. The electrical conductivity of the composite carbon aerogel with 5 wt % additive showed improvement over the plain carbon aerogel with respective values of 144 S/m and 128 S/m. The specific capacitance evaluated for CA and CCA are 102 and 118 F/g at scan rate of 10mV/s with improvement of ˜16%.

Methodological approaches in conducting overviews: current state in HTA agencies.

PubMed

Pieper, Dawid; Antoine, Sunya-Lee; Morfeld, Jana-Carina; Mathes, Tim; Eikermann, Michaela

2014-09-01

Overviews search for reviews rather than for primary studies. They might have the potential to support decision making within a shorter time frame by reducing production time. We aimed to summarize available instructions for authors intending to conduct overviews as well as the currently applied methodology of overviews in international Health Technology Assessment (HTA) agencies. We identified 127 HTA agencies and scanned their websites for methodological handbooks as well as published overviews as HTA reports. Additionally, we contacted HTA agencies by e-mail to retrieve possible unidentified handbooks or other related sources. In total, eight HTA agencies providing methodological support were found. Thirteen HTA agencies were found to have produced overviews since 2007, but only six of them published more than four overviews. Overviews were mostly employed in HTA products related to rapid assessment. Additional searches for primary studies published after the last review are often mentioned in order to update results. Although the interest in overviews is rising, little methodological guidance for the conduct of overviews is provided by HTA agencies. Overviews are of special interest in the context of rapid assessments to support policy-making within a short time frame. Therefore, empirical work on overviews needs to be extended. National strategies and experience should be disclosed and discussed. Copyright © 2013 John Wiley & Sons, Ltd.

Current collectors for improved safety

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

Abdelmalak, Michael Naguib; Allu, Srikanth; Dudney, Nancy J.

A battery electrode assembly includes a current collector with conduction barrier regions having a conductive state in which electrical conductivity through the conduction barrier region is permitted, and a safety state in which electrical conductivity through the conduction barrier regions is reduced. The conduction barrier regions change from the conductive state to the safety state when the current collector receives a short-threatening event. An electrode material can be connected to the current collector. The conduction barrier regions can define electrical isolation subregions. A battery is also disclosed, and methods for making the electrode assembly, methods for making a battery, andmore » methods for operating a battery.« less

Decremental Response to High-Frequency Trains of Acetylcholine Pulses but Unaltered Fractional Ca2+ Currents in a Panel of “Slow-Channel Syndrome” Nicotinic Receptor Mutants

PubMed Central

Elenes, Sergio; Decker, Michael; Cymes, Gisela D.

2009-01-01

The slow-channel congenital myasthenic syndrome (SCCMS) is a disorder of the neuromuscular junction caused by gain-of-function mutations to the muscle nicotinic acetylcholine (ACh) receptor (AChR). Although it is clear that the slower deactivation time course of the ACh-elicited currents plays a central role in the etiology of this disease, it has been suggested that other abnormal properties of these mutant receptors may also be critical in this respect. We characterized the kinetics of a panel of five SCCMS AChRs (αS269I, βV266M, εL221F, εT264P, and εL269F) at the ensemble level in rapidly perfused outside-out patches. We found that, for all of these mutants, the peak-current amplitude decreases along trains of nearly saturating ACh pulses delivered at physiologically relevant frequencies in a manner that is consistent with enhanced entry into desensitization during the prolonged deactivation phase. This suggests that the increasingly reduced availability of activatable AChRs upon repetitive stimulation may well contribute to the fatigability and weakness of skeletal muscle that characterize this disease. Also, these results emphasize the importance of explicitly accounting for entry into desensitization as one of the pathways for burst termination, if meaningful mechanistic insight is to be inferred from the study of the effect of these naturally occurring mutations on channel function. Applying a novel single-channel–based approach to estimate the contribution of Ca2+ to the total cation currents, we also found that none of these mutants affects the Ca2+-conduction properties of the AChR to an extent that seems to be of physiological importance. Our estimate of the Ca2+-carried component of the total (inward) conductance of wild-type and SCCMS AChRs in the presence of 150 mM Na+, 1.8 mM Ca2+, and 1.7 mM Mg2+ on the extracellular side of cell-attached patches turned out be in the 5.0–9.4 pS range, representing a fractional Ca2+ current of ∼14%, on average. Remarkably, these values are nearly identical to those we estimated for the NR1-NR2A N-methyl-d-aspartate receptor (NMDAR), which has generally been considered to be the main neurotransmitter-gated pathway of Ca2+ entry into the cell. Our estimate of the rat NMDAR Ca2+ conductance (using the same single-channel approach as for the AChR but in the nominal absence of extracellular Mg2+) was 7.9 pS, corresponding to a fractional Ca2+ current of 13%. PMID:19171769

Electrochemical immobilization of Fluorescent labelled probe molecules on a FTO surface for affinity detection based on photo-excited current

NASA Astrophysics Data System (ADS)

Haruyama, Tetsuya; Wakabayashi, Ryo; Cho, Takeshi; Matsuyama, Sho-taro

2011-10-01

Photo-excited current can be generated at a molecular interface between a photo-excited molecules and a semi-conductive material in appropriate condition. The system has been recognized for promoting photo-energy devices such as an organic dye sensitized solar-cell. The photo-current generated reactions are totally dependent on the interfacial energy reactions, which are in a highly fluctuated interfacial environment. The authors investigated the photo-excited current reaction to develop a smart affinity detection method. However, in order to perform both an affinity reaction and a photo-excited current reaction at a molecular interface, ordered fabrications of the functional (affinity, photo-excitation, etc.) molecules layer on a semi-conductive surface is required. In the present research, we would like to present the fabrication and functional performance of photo-excited current-based affinity assay device and its application for detection of endocrine disrupting chemicals. On the FTO surface, fluorescent pigment labelled affinity peptide was immobilized through the EC tag (electrochemical-tag) method. The modified FTO produced a current when it was irradiated with diode laser light. However, the photo current decreased drastically when estrogen (ES) coexisted in the reaction solution. In this case, immobilized affinity probe molecules formed a complex with ES and estrogen receptor (ER). The result strongly suggests that the photo-excited current transduction between probe molecule-labelled cyanine pigment and the FTO surface was partly inhibited by a complex that formed at the affinity oligo-peptide region in a probe molecule on the FTO electrode. The bound bulky complex may act as an impediment to perform smooth transduction of photo-excited current in the molecular interface. The present system is new type of photo-reaction-based analysis. This system can be used to perform simple high-sensitive homogeneous assays.

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

DOEpatents

Vail, III, William Banning

2001-01-01

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

Response of Nuclear Power Plant Instrumentation Cables Exposed to Fire Conditions.

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

Muna, Alice Baca; LaFleur, Chris Bensdotter; Brooks, Dusty Marie

This report presents the results of instrumentation cable tests sponsored by the US Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research and performed at Sandia National Laboratories (SNL). The goal of the tests was to assess thermal and electrical response behavior under fire-exposure conditions for instrumentation cables and circuits. The test objective was to assess how severe radiant heating conditions surrounding an instrumentation cable affect current or voltage signals in an instrumentation circuit. A total of thirty-nine small-scale tests were conducted. Ten different instrumentation cables were tested, ranging from one conductor to eight-twisted pairs. Because the focus of themore » tests was thermoset (TS) cables, only two of the ten cables had thermoplastic (TP) insulation and jacket material and the remaining eight cables were one of three different TS insulation and jacket material. Two instrumentation cables from previous cable fire testing were included, one TS and one TP. Three test circuits were used to simulate instrumentation circuits present in nuclear power plants: a 4–20 mA current loop, a 10–50 mA current loop and a 1–5 VDC voltage loop. A regression analysis was conducted to determine key variables affecting signal leakage time.« less

Exploring use of the ICF in health education.

PubMed

Bornbaum, Catherine C; Day, Adam M B; Izaryk, Kristen; Morrison, Stephanie J; Ravenek, Michael J; Sleeth, Lindsay E; Skarakis-Doyle, Elizabeth

2015-01-01

Currently, little is known regarding use of the International Classification of Functioning, Disability and Health (ICF) in health education applications. Therefore, this review sought to examine the scope of work that has been conducted regarding the application of the ICF in health education. A review of the current literature related to use of the ICF in health education programs was conducted. Twelve electronic databases were searched in accordance with a search protocol developed by a health sciences librarian. In total, 17,878 records were reviewed, and 18 articles met the criteria for inclusion in this review. Current evidence regarding use of the ICF in healthcare education revealed that program and participant properties can be essential facilitators or barriers to successful education programs. In addition, gaps in comprehensive outcome measurement were revealed as areas for future attention. Educational applications of the ICF are very much a work in progress as might be expected given the ICF's existence for only a little over a decade. To advance use of the ICF in education, it is important to incorporate the measurement of both knowledge acquisition and behavior change related to ICF-based programs. Ultimately, widespread implementation of the ICF represents not only a substantial opportunity but also poses a significant challenge.

Survey of university programs in remote sensing funded under grants from the NASA University-Space Applications program

NASA Technical Reports Server (NTRS)

Madigan, J. A.; Earhart, R. W.

1978-01-01

NASA's Office of Space and Terrestrial Applications (OSTA) is currently assessing approaches to transferring NASA technology to both the public and private sectors. As part of this assessment, NASA is evaluating the effectiveness of an ongoing program in remote sensing technology transfer conducted by 20 university contractors/grantees, each supported totally or partially by NASA funds. The University-Space Applications program has as its objective the demonstration of practical benefits from the use of remote sensing technology to a broad spectrum of new users, principally in state and local governments. To evaluate the University-Space Applications program, NASA has a near-term requirement for data on each university effort including total funding, funding sources, length of program, program description, and effectiveness measures.

Phase III integrated water recovery testing at MSFC - Partially closed hygiene loop and open potable loop results and lessons learned

NASA Technical Reports Server (NTRS)

Bagdigian, R. M.; Traweek, M. S.; Griffith, G. K.; Griffin, M. R.

1991-01-01

A series of tests has been conducted at the NASA Marshall Space Flight Center (MSFC) to evaluate the performance of a predevelopment water recovery system. Potable, hygiene, and urine reclamation subsystems were integrated with end-use equipment items and successfully operated in open and partially closed-loop modes, with man-in-the-loop, for a total of 28 days. Several significant subsystem physical anomalies were encountered during testing. Reclaimed potable and hygiene water generally met the current Space Station Freedom (SSF) water quality specifications for inorganic and microbiological constituents, but exceeded the maximum allowable concentrations for Total Organic Carbon (TOC). This paper summarizes the test objectives, system design, test activities/protocols, significant results/anomalies, and major lessons learned.

U-Th-Pb systematics on lunar rocks and inferences about lunar evolution and the age of the moon

NASA Technical Reports Server (NTRS)

Tera, F.; Wasserburg, G. J.

1974-01-01

The investigation reported continues a study conducted by Tera et al. (1974). An attempt is made to summarize all of the data currently available in the literature on terra materials and to discuss the implications of the upper intersection with the concordia curve. Data on total rocks and some plagioclase separates are presented in a graph. The data appear to give further support to a model of a terminal lunar cataclysm associated with intense global bombardment at about 3.9 aeons.

Method and apparatus for casting conductive and semiconductive materials

DOEpatents

Ciszek, Theodore F.

1986-01-01

A method and apparatus is disclosed for casting conductive and semiconduce materials. The apparatus includes a plurality of conductive members arranged to define a container-like area having a desired cross-sectional shape. A portion or all of the conductive or semiconductive material which is to be cast is introduced into the container-like area. A means is provided for inducing the flow of an electrical current in each of the conductive members, which currents act collectively to induce a current flow in the material. The induced current flow through the conductive members is in a direction substantially opposite to the induced current flow in the material so that the material is repelled from the conductive members during the casting process.

76 FR 39981 - Agency Information Collection Activities; Submission for OMB Review; Joint Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-07

... for the first year to convert systems and conduct training. Estimated Total Annual Burden: National... 124,832 burden hours for the first year to convert systems and conduct training. Total: 571,302 burden... 188 burden hours for the first year to convert systems and conduct training. Estimated Total Annual...

Financial Impact of Cancer Drug Wastage and Potential Cost Savings From Mitigation Strategies.

PubMed

Leung, Caitlyn Y W; Cheung, Matthew C; Charbonneau, Lauren F; Prica, Anca; Ng, Pamela; Chan, Kelvin K W

2017-07-01

Cancer drug wastage occurs when a parenteral drug within a fixed vial is not administered fully to a patient. This study investigated the extent of drug wastage, the financial impact on the hospital budget, and the cost savings associated with current mitigation strategies. We conducted a cross-sectional study in three University of Toronto-affiliated hospitals of various sizes. We recorded the actual amount of drug wasted over a 2-week period while using current mitigation strategies. Single-dose vial cancer drugs with the highest wastage potentials were identified (14 drugs). To calculate the hypothetical drug wastage with no mitigation strategies, we determined how many vials of drugs would be needed to fill a single prescription. The total drug costs over the 2 weeks ranged from $50,257 to $716,983 in the three institutions. With existing mitigation strategies, the actual drug wastage over the 2 weeks ranged from $928 to $5,472, which was approximately 1% to 2% of the total drug costs. In the hypothetical model with no mitigation strategies implemented, the projected drug cost wastage would have been $11,232 to $149,131, which accounted for 16% to 18% of the total drug costs. As a result, the potential annual savings while using current mitigation strategies range from 15% to 17%. The financial impact of drug wastage is substantial. Mitigation strategies lead to substantial cost savings, with the opportunity to reinvest those savings. More research is needed to determine the appropriate methods to minimize risk to patients while using the cost-saving mitigation strategies.

STAKEHOLDERS' PERCEPTIONS OF HEALTH TECHNOLOGY ASSESSMENT IN TURKEY.

PubMed

Ozturk, Kirstin; Karadayı, Bilgehan; Şener, Olgun

2018-01-01

In April of 2014, the Turkish Ministry of Health held the First Annual Health Technology Assessment (HTA) Meeting in Antalya. The objectives were to understand the perceptions of stakeholders regarding the current status of HTA and document their recommendations and strategies for promoting systematic use of HTA in Turkey. The study was conducted using a qualitative written survey assessing current compliance with the fifteen HTA principles suggested by Drummond et al. (Key principles for the improved conduct of health technology assessments for resource allocation decision. Int J Technol Assess Health Care. 2008;24:244-258) and a qualitative method referred to as the Collective Intelligence Platform®. A total of 216 stakeholders representing academic, public, and the private health sector attended the annual meeting; 178 completed the survey and 183 participated in the Platform. Quantitative Results: Survey participants reported that, although Turkey does not currently fully comply with any of the fifteen HTA principles, there is some compliance with all of them. The overall average score for all fifteen principles was 3.04. Quantitivate Results: Participants recommended a more transparent, independent, and evidence-based policy decision-making system through better coordination of HTA activities, data aggregation, capacity development, and a national HTA core model and framework. Platform participants described the current HTA environment as disjointed and lacking in resources and support from policy-making leaders. Despite the persisting challenges, awareness of the strengths and weaknesses of the current system combined with increasing interaction among Turkish stakeholders and the international HTA community can meaningfully contribute to the continued development and promotion of HTA in Turkey.

Origin of temperature dependent conduction of current from n-4H-SiC into silicon dioxide films at high electric fields

NASA Astrophysics Data System (ADS)

Xiang, An; Xu, Xingliang; Zhang, Lin; Li, Zhiqiang; Li, Juntao; Dai, Gang

2018-02-01

The conduction of current from n-4H-SiC into pyrogenic and dry oxidized films is studied. Anomalous current conduction was observed at a high electric field above 8 MV/cm for dry oxidized metal-oxide-semiconductor (MOS) capacitors, which cannot be interpreted in the framework of pure Fowler-Nordheim tunneling. The temperature-dependent current measurement and density of interface trap estimated from the hi-lo method for the SiO2/4H-SiC interface revealed that the combined current conduction of Fowler-Nordheim and Poole-Frenkel emission is responsible for the current conduction in both pyrogenic and dry oxidized MOS capacitors. Furthermore, the origin of temperature dependent current conduction is the Poole-Frenkel emission via the carbon pair defect trap level at 1.3 eV below the conduction band edge of SiO2. In addition, with the dry oxidized capacitors, the enhanced temperature dependent current above 8 MV/cm is attributed to the PF emission via a trap level at 1.47 eV below the conduction band edge of SiO2, which corresponds to another configuration of a carbon pair defect in SiO2 films.

Income, income inequality and youth smoking in low- and middle-income countries.

PubMed

Li, David X; Guindon, G Emmanuel

2013-04-01

To examine the relationships between income, income inequality and current smoking among youth in low- and middle-income countries. Pooled cross-sectional data from the Global Youth Tobacco Surveys, conducted in low- and middle-income countries, were used to conduct multi-level logistic analyses that accounted for the nesting of students in schools and of schools in countries. A total of 169 283 students aged 13-15 from 63 low- and middle-income countries. Current smoking was defined as having smoked at least one cigarette in the past 30 days. Gross domestic product (GDP) per capita was our measure of absolute income. Contemporaneous and lagged (10-year) Gini coefficients, as well as the income share ratio of the top decile of incomes to the bottom decile, were our measures of income inequality. Our analyses reveal a significant positive association between levels of income and youth smoking. We find that a 10% increase in GDP per capita increases the odds of being a current smoker by at least 2.5%, and potentially considerably more. Our analyses also suggest a relationship between the distribution of incomes and youth smoking: youth from countries with more unequal distributions of income tend to have higher odds of currently smoking. There is a positive association between gross domestic product and the odds of a young person in a low- and middle-income country being a current smoker. Given the causal links between smoking and a wide range of youth morbidities, the association between smoking and income inequality may underlie a substantial portion of the health disparities observed that are currently experiencing rapid economic growth. © 2012 The Authors, Addiction © 2012 Society for the Study of Addiction.

Initial surgical management of ulcerative colitis in the biologic era.

PubMed

Geltzeiler, Cristina B; Lu, Kim C; Diggs, Brian S; Deveney, Karen E; Keyashian, Kian; Herzig, Daniel O; Tsikitis, Vassiliki L

2014-12-01

The initial minimum operation for ulcerative colitis is a total abdominal colectomy. Healthy patients may undergo proctectomy at the same time; however, for ill patients, proctectomy is delayed. Since the introduction of biologic medications in 2005, ulcerative colitis medical management has changed dramatically. We examined how operative management for ulcerative colitis has changed from the prebiologic to biologic eras. We conducted a retrospective review of data on patients with ulcerative colitis who were included in the Nationwide Inpatient Sample database. This study was conducted at a single university. A total of 1,547,852 patients with ulcerative colitis who were admitted to a US hospital from 1991 to 2011 were included in the study. We examined patients whose initial operation consisted of total abdominal colectomy without proctectomy versus a total proctocolectomy with or without a pouch. We also examined which operation was done at the time of the construction of an ileoanal pouch. Patients who underwent colectomy and pouch construction in the same hospitalization were compared with those who received pouch formation at a subsequent hospitalization. Ulcerative colitis-related admissions rose by 170% during the years examined, and the number of patients who required total abdominal colectomy increased by 44%. Total abdominal colectomy increased by 15%, as opposed to total proctocolectomy (p < 0.001). Pouch construction at a subsequent operation increased by 16% (p = 0.002). Since 2008, total abdominal colectomy has surpassed total proctocolectomy as the most common initial surgical intervention for ulcerative colitis. The Nationwide Inpatient Sample is a retrospective database, and we were limited to examining the variables within it. Total abdominal colectomy is currently the most common initial operation for patients with ulcerative colitis, and an ileoanal pouch is more frequently constructed at a subsequent hospitalization. These trends coincide with the initiation of biologic treatments and may imply that patients are acutely ill at the time of initial operation. Alternately, there may be surgeon-perceived bias of increased surgical risk or a shift in care to specialized surgeons for pouch construction.

Mechanism and kinetics of electrochemical degradation of uric acid using conductive-diamond anodes.

PubMed

Dbira, Sondos; Bensalah, Nasr; Bedoui, Ahmed

2016-12-01

Uric acid (UA) is one of the principal effluents of urine wastewaters, widely used in agriculture as fertilizer, which is potentially dangerous and biorefractory. Hence, the degradation of UA (2,6,8-trihydroxy purine) in aqueous solution of pH 3.0 has been studied by conductive-diamond electrochemical oxidation. Hydroxyl radicals formed from water oxidation at the surface of boron-doped diamond anodes were the main oxidizing agents. Effects of current density and supporting electrolyte on the degradation rate and process efficiency are assessed. Results show that the increase of current density from 20 to 60 mA cm(-2) leads to a decrease in the efficiency of the electrochemical process. In addition, the best degradation occurred in the presence of NaCl as conductive electrolyte. Interestingly, an almost total mineralization of 50 ppm UA was obtained when anodic oxidation was performed at low current densities (20 mA cm(-2)) and in the presence of NaCl. This result confirmed that the electrolysis using diamond anodes is a very interesting technology for the treatment of UA. The identification of UA transformation products was performed by high-performance liquid chromatography (HPLC). HPLC analysis of treated solutions revealed that oxalic acid and urea were the two intermediates found. Oxalic acid was the most persistent product. Based on detected intermediates and bibliographic research, a mechanism of UA mineralization by anodic oxidation has been proposed. Ionic chromatography analysis confirmed the release of [Formula: see text] and [Formula: see text] ions during UA mineralization.

Pressure Effects on Oxygen Concentration Flammability Thresholds of Materials for Aerospace Applications

NASA Technical Reports Server (NTRS)

Hirsch, David; Williams, Jim; Beeson, Harold

2006-01-01

Spacecraft materials selection is based on an upward flammability test conducted in a quiescent environment in the highest-expected oxygen-concentration environment. However, NASA s advanced space exploration program is anticipating using various habitable environments. Because limited data is available to support current program requirements, a different test logic is suggested to address these expanded atmospheric environments through the determination of materials self-extinguishment limits. This paper provides additional pressure effects data on oxygen concentration and partial pressure self-extinguishment limits under quiescent conditions. For the range of total pressures tested, the oxygen concentration and oxygen partial pressure flammability thresholds show a near linear function of total pressure. The oxygen concentration/oxygen partial pressure flammability thresholds depend on the total pressure and appear to increase with increasing oxygen concentration (and oxygen partial pressure). For the Constellation Program, the flammability threshold information will allow NASA to identify materials with increased flammability risk because of oxygen concentration and total pressure changes, minimize potential impacts, and allow for development of sound requirements for new spacecraft and extraterrestrial landers and habitats.

The Noise Level Optimization for Induction Magnetometer of SEP System

NASA Astrophysics Data System (ADS)

Zhu, W.; Fang, G.

2011-12-01

The Surface Electromagnetic Penetration (SEP) System, subsidized by the SinoProbe Plan in China, is designed for 3D conductivity imaging in geophysical mineral exploration, underground water distribution exploration, oil and gas reservoir exploration. Both the Controlled Source Audio Magnetotellurics (CSAMT) method and Magnetotellurics (MT) method can be surveyed by SEP system. In this article, an optimization design is introduced, which can minimize the noise level of the induction magnetometer for SEP system magnetic field's acquisition. The induction magnetometer transfers the rate of the magnetic field's change to voltage signal by induction coil, and amplified it by Low Noise Amplifier The noise parts contributed to the magnetometer are: the coil's thermal noise, the equivalent input voltage and current noise of the pre-amplifier. The coil's thermal noise is decided by coil's DC resistance. The equivalent input voltage and current noise of the pre-amplifier depend on the amplifier's type and DC operation condition. The design here optimized the DC operation point of pre-amplifier, adjusted the DC current source, and realized the minimum of total noise level of magnetometer. The calculation and test results show that: the total noise is about 1pT/√Hz, the thermal noise of coils is 1.7nV/√Hz, the preamplifier equivalent input voltage and current noise is 3nV/ √Hz and 0.1pA/√Hz, the weight of the magnetometer is 4.5kg and meet the requirement of SEP system.

Transmission of electric fields due to distributed cloud charges in the atmosphere-ionosphere system

NASA Astrophysics Data System (ADS)

Paul, Suman; De, S. S.; Haldar, D. K.; Guha, G.

2017-10-01

The transmission of electric fields in the lower atmosphere by thunder clouds with a suitable charge distribution profile has been modeled. The electromagnetic responses of the atmosphere are presented through Maxwell's equations together with a time-varying source charge distribution. The conductivities are taken to be exponentially graded function of altitude. The radial and vertical electric field components are derived for isotropic, anisotropic and thundercloud regions. The analytical solutions for the total Maxwell's current which flows from the cloud into the ionosphere under DC and quasi-static conditions are obtained for isotropic region. We found that the effect of charge distribution in thunderclouds produced by lightning discharges diminishes rapidly with increasing altitudes. Also, it is found that time to reach Maxwell's currents a maximum is higher for higher altitudes.

[Breast augmentation by implants: a review of surgical practices. A study among French plastic surgeons].

PubMed

Chekaroua, K; Delay, E

2005-10-01

In the framework of the 2005 report on mammary implants prepared by the Société française de chirurgie plastique reconstructrice et esthétique (SOF.CPRE), we conducted a survey among french plastic surgeons involved in the field. We elaborated a questionnaire that we distributed twice to the 600 members of the society; a total of 261 responded. Analysis of the data collected provides information on the socioprofessional characteristics of the responding surgeons, and on the devices, products and techniques they use. Finally, the survey has permitted to identify their qualitative perception of breast implant products currently available. Ranking these items by order of frequency provides a snapshot of the current procedures and practices in use for breast augmentation surgery in France.

A 5.9 tesla conduction-cooled coil composed of a stack of four single pancakes wound with YBCO wide tapes

NASA Astrophysics Data System (ADS)

Iwai, Sadanori; Miyazaki, Hiroshi; Tosaka, Taizo; Tasaki, Kenji; Urata, Masami; Ioka, Shigeru; Ishii, Yusuke

2013-11-01

We have been developing a conduction-cooled coil wound with YBCO-coated conductors for HTS applications. Previously, we have fabricated a coil composed of a stack of 12 single pancakes wound with 4 mm-wide YBCO tapes. This coil had a central magnetic field as high as 5.1 T at 10 K under conduction-cooled conditions. In the present study, we fabricated and tested a coil composed of a stack of four single pancakes wound with 12 mm-wide YBCO tapes. The total size of the coil and the Jc value of the tapes were almost the same as those of the former coil. At 77 K, the voltage-current characteristics showed a high n-value of 24, confirming that the coil had no degradation. Furthermore, in a conduction-cooled configuration at 20 K to 60 K, the coil showed a high n-value of over 20. At 20 K, the central magnetic field reached 5.9 T at 903 A, which is 1.3-times higher than that of the former coil.

Serum calcium and incident diabetes: an observational study and meta-analysis.

PubMed

Sing, C W; Cheng, V K F; Ho, D K C; Kung, A W C; Cheung, B M Y; Wong, I C K; Tan, K C B; Salas-Salvadó, J; Becerra-Tomas, N; Cheung, C L

2016-05-01

The study aimed to prospectively evaluate if serum calcium is related to diabetes incidence in Hong Kong Chinese. The results showed that serum calcium has a significant association with increased risk of diabetes. The result of meta-analysis reinforced our findings. This study aimed to evaluate the association of serum calcium, including serum total calcium and albumin-corrected calcium, with incident diabetes in Hong Kong Chinese. We conducted a retrospective cohort study in 6096 participants aged 20 or above and free of diabetes at baseline. Serum calcium was measured at baseline. Incident diabetes was determined from several electronic databases. We also searched relevant databases for studies on serum calcium and incident diabetes and conducted a meta-analysis using fixed-effect modeling. During 59,130.9 person-years of follow-up, 631 participants developed diabetes. Serum total calcium and albumin-corrected calcium were associated with incident diabetes in the unadjusted model. After adjusting for demographic and clinical variables, the association remained significant only for serum total calcium (hazard ratio (HR), 1.32 (95 % confidence interval (CI), 1.02-1.70), highest vs. lowest quartile). In a meta-analysis of four studies including the current study, both serum total calcium (pooled risk ratio (RR), 1.38 (95 % CI, 1.15-1.65); I (2) = 5 %, comparing extreme quantiles) and albumin-corrected calcium (pooled RR, 1.29 (95 % CI, 1.03-1.61); I (2) = 0 %, comparing extreme quantiles) were associated with incident diabetes. Penalized regression splines showed that the association of incident diabetes with serum total calcium and albumin-correlated calcium was non-linear and linear, respectively. Elevated serum calcium concentration is associated with incident diabetes. The mechanism underlying this association warrants further investigation.

The epidemiology of cigarette smoking in Hong Kong Chinese women.

PubMed

Lau, E M C; Lee, P; Lynn, H; Sham, A; Woo, J

2003-11-01

Smoking in women is a well-recognized public health problem. In many developed countries, cigarette smoking is now the single most important preventable cause of premature death in women. There are relatively few data on the epidemiology of cigarette smoking in Asian women, and this study examined the prevalence of and factors predisposing Chinese women to smoke cigarettes in Hong Kong. A territory-wide random telephone survey of 26,716 households in Hong Kong was conducted. A total of 1064 current smokers and 291 ex-smokers were identified in these household, and in-depth interviews of 791 current smokers, 221 ex-smokers, and 1012 controls were conducted. The prevalence of cigarette smoking was 4.5% in women who were 25 years or younger, 2.6% in women aged 46-65 years, and 2.2% in women aged 65 years or older. Sixty-four percent of current smokers started when they were 19 years or younger. The main reasons for the initiation of cigarette smoking were the influence of friends, curiosity, feeling bored, or being idle. Current smokers and ex-smokers tended to have positive images of women who smoked. The following risk factors were found to be significant for cigarette smoking: less than university education, unemployment, being divorced, having a husband who smoked, and a low score on the perceived harms of cigarette smoking. Cigarette smoking is more prevalent in younger women in Hong Kong; and psychosocial issues should be addressed to prevent future epidemics.

Evaluation of mechanical deformation and distributive magnetic loads with different mechanical constraints in two parallel conducting bars

NASA Astrophysics Data System (ADS)

Lee, Ho-Young; Lee, Se-Hee

2017-08-01

Mechanical deformation, bending deformation, and distributive magnetic loads were evaluated numerically and experimentally for conducting materials excited with high current. Until now, many research works have extensively studied the area of magnetic force and mechanical deformation by using coupled approaches such as multiphysics solvers. In coupled analysis for magnetoelastic problems, some articles and commercial software have presented the resultant mechanical deformation and stress on the body. To evaluate the mechanical deformation, the Lorentz force density method (LZ) and the Maxwell stress tensor method (MX) have been widely used for conducting materials. However, it is difficult to find any experimental verification regarding mechanical deformation or bending deformation due to magnetic force density. Therefore, we compared our numerical results to those from experiments with two parallel conducting bars to verify our numerical setup for bending deformation. Before showing this, the basic and interesting coupled simulation was conducted to test the mechanical deformations by the LZ (body force density) and the MX (surface force density) methods. This resulted in MX gave the same total force as LZ, but the local force distribution in MX introduced an incorrect mechanical deformation in the simulation of a solid conductor.

Indicators: Conductivity

EPA Pesticide Factsheets

Conductivity is a measure of the ability of water to pass an electrical current. Because dissolved salts and other inorganic chemicals conduct electrical current, conductivity increases as salinity increases.

Physicochemical characterization of Lavandula spp. honey with FT-Raman spectroscopy.

PubMed

Anjos, Ofélia; Santos, António J A; Paixão, Vasco; Estevinho, Letícia M

2018-02-01

This study aimed to evaluate the potential of FT-Raman spectroscopy in the prediction of the chemical composition of Lavandula spp. monofloral honey. Partial Least Squares (PLS) regression models were performed for the quantitative estimation and the results were correlated with those obtained using reference methods. Good calibration models were obtained for electrical conductivity, ash, total acidity, pH, reducing sugars, hydroxymethylfurfural (HMF), proline, diastase index, apparent sucrose, total flavonoids content and total phenol content. On the other hand, the model was less accurate for pH determination. The calibration models had high r 2 (ranging between 92.8% and 99.9%), high residual prediction deviation - RPD (ranging between 4.2 and 26.8) and low root mean square errors. These results confirm the hypothesis that FT-Raman is a useful technique for the quality control and chemical properties' evaluation of Lavandula spp honey. Its application may allow improving the efficiency, speed and cost of the current laboratory analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

Is photobiomodulation (PBM) effective for the treatment of dentin hypersensitivity? A systematic review.

PubMed

Machado, Alana Cristina; Viana, Ítallo Emídio Lira; Farias-Neto, Aloisio Melo; Braga, Mariana Minatel; de Paula Eduardo, Carlos; de Freitas, Patricia Moreira; Aranha, Ana Cecilia Corrêa

2018-05-01

The present study aims to evaluate the current scientific data regarding the effectiveness of photobiomodulation (PBM) in the treatment of dentin hypersensitivity (DH) as an alternative method for pain control. A systematic review was conducted to assess the effectiveness of PBM as treatment for DH. A complete literature search was performed up to October 2016. Searches were conducted using Boolean operators and MeSH terms. References of all selected full-text articles and related reviews were scanned. A total of 280 articles were identified (241 articles were excluded by the title and abstract). Of the 39 articles selected for analysis, 36 were excluded because they presented one or more exclusion criteria. Therefore, three articles were qualified for inclusion in this systematic review. PBM may not lead to adverse effects provided that adequately controlled parameters are followed when treating DH. More consistent studies should be conducted in order to adequately observe the advantageous therapeutic effect of PBM.

Experimental Comparison of Piezoelectric and Magnetostrictive Shunt Dampers

NASA Technical Reports Server (NTRS)

Asnani, Vivake M.; Deng, Zhangxian; Dapino, Marcelo J.; Scheidler, Justin J.

2016-01-01

A novel mechanism called the vibration ring is being developed to enable energy conversion elements to be incorporated into the driveline of a helicopter or other rotating machines. Unwanted vibration is transduced into electrical energy, which provides a damping effect on the driveline. The generated electrical energy may also be used to power other devices (e.g., health monitoring sensors). PZT (piezoceramic) and PMN-30PT (single crystal) stacks, as well as a Tb_0.3 Dy_0.7 Fe_1.92 (Terfenol-D) rod with a bias magnet array and a pickup coil, were tested as alternative energy conversion elements to use within the vibration ring. They were tuned for broadband damping using shunt resistors, and dynamic compression testing was conducted in a high-speed load frame. Energy conversion was experimentally optimized at 750Hz by tuning the applied bias stress and resistance values. Dynamic testing was conducted up to 1000Hz to determine the effective compressive modulus, shunt loss factor, internal loss factor, and total loss factor. Some of the trends of modulus and internal loss factor versus frequency were unexplained. The single crystal device exhibited the greatest shunt loss factor whereas the Terfenol-D device had the highest internal and total loss factors. Simulations revealed that internal losses in the Terfenol-D device were elevated by eddy current effects, and an improved magnetic circuit could enhance its shunt damping capabilities. Alternatively, the Terfenol-D device may be simplified to utilize only the eddy current dissipation mechanism (no pickup coil or shunt) to create broadband damping.

Experimental Comparison of Piezoelectric and Magnetostrictive Shunt Dampers

NASA Technical Reports Server (NTRS)

Asnani, Vivake M.; Deng, Zhangxian; Scheidler, Justin J.; Dapino, Marcelo J.

2016-01-01

A novel mechanism called the vibration ring is being developed to enable energy conversion elements to be incorporated into the driveline of a helicopter or other rotating machines. Unwanted vibration is transduced into electrical energy, which provides a damping effect on the driveline. The generated electrical energy may also be used to power other devices (e.g., health monitoring sensors). PZT (piezoceramic) and PMN-30%PT (single crystal) stacks, as well as a Tb_0.3 Dy_0.7 Fe_1.92 (Terfenol-D) rod with a bias magnet array and a pickup coil, were tested as alternative energy conversion elements to use within the vibration ring. They were tuned for broadband damping using shunt resistors, and dynamic compression testing was conducted in a high-speed load frame. Energy conversion was experimentally optimized at 750Hz by tuning the applied bias stress and resistance values. Dynamic testing was conducted up to 1000Hz to determine the effective compressive modulus, shunt loss factor, internal loss factor, and total loss factor. Some of the trends of modulus and internal loss factor versus frequency were unexplained. The single crystal device exhibited the greatest shunt loss factor whereas the Terfenol-D device had the highest internal and total loss factors. Simulations revealed that internal losses in the Terfenol-D device were elevated by eddy current effects, and an improved magnetic circuit could enhance its shunt damping capabilities. Alternatively, the Terfenol-D device may be simplified to utilize only the eddy current dissipation mechanism (no pickup coil or shunt) to create broadband damping.

Experimental comparison of piezoelectric and magnetostrictive shunt dampers

NASA Astrophysics Data System (ADS)

Asnani, Vivake M.; Deng, Zhangxian; Scheidler, Justin J.; Dapino, Marcelo J.

2016-04-01

A novel mechanism called the vibration ring is being developed to enable energy conversion elements to be incorporated into the driveline of a helicopter or other rotating machines. Unwanted vibration is transduced into electrical energy, which provides a damping effect on the driveline. The generated electrical energy may also be used to power other devices (e.g., health monitoring sensors). PZT (`piezoceramic') and PMN-30%PT (`single crystal') stacks, as well as a Tb0.3Dy0.7Fe1.92 (`Terfenol-D') rod with a bias magnet array and a pickup coil, were tested as alternative energy conversion elements to use within the vibration ring. They were tuned for broadband damping using shunt resistors, and dynamic compression testing was conducted in a high-speed load frame. Energy conversion was experimentally optimized at 750Hz by tuning the applied bias stress and resistance values. Dynamic testing was conducted up to 1000Hz to determine the effective compressive modulus, shunt loss factor, internal loss factor, and total loss factor. Some of the trends of modulus and internal loss factor versus frequency were unexplained. The single crystal device exhibited the greatest shunt loss factor whereas the Terfenol-D device had the highest internal and total loss factors. Simulations revealed that internal losses in the Terfenol-D device were elevated by eddy current effects, and an improved magnetic circuit could enhance its shunt damping capabilities. Alternatively, the Terfenol-D device may be simplified to utilize only the eddy current dissipation mechanism (no pickup coil or shunt) to create broadband damping.

Status of the NEXT Ion Thruster Long-Duration Test After 10,100 hr and 207 kg Demonstrated

NASA Technical Reports Server (NTRS)

Herman, Daniel A.; Soulas, George C.; Patterson, Michael J.

2008-01-01

The NASA s Evolutionary Xenon Thruster (NEXT) program is developing the next-generation ion propulsion system with significant enhancements beyond the state-of-the-art in ion propulsion to provide future NASA science missions with enhanced mission capabilities at a low total development cost. As part of a comprehensive thruster service life assessment utilizing both testing and analyses, a Long-Duration Test (LDT) was initiated to validate and qualify the NEXT propellant throughput capability to a qualification-level of 450 kg, 1.5 times the mission-derived throughput requirement of 300 kg. This wear test is being conducted with a modified, flight-representative NEXT engineering model ion thruster, designated EM3. As of June 21, 2007, the thruster has accumulated 10,100 hr of operation at the thruster full-input-power of 6.9 kW with 3.52 A beam current and 1800 V beam power supply voltage. The thruster has processed 207 kg of xenon and demonstrated a total impulse of 8.5 106 N-s; the highest total impulse ever demonstrated by an ion thruster in the history of space propulsion. Thruster performance tests are conducted periodically over the entire NEXT throttle table with input power ranging 0.5 to 6.9 kW. Overall ion thruster performance parameters including thrust, input power, specific impulse, and thruster efficiency have been nominal with little variation to date. Lifetime-limiting component erosion rates have been consistent with the NEXT service life assessment, which predicts the earliest failure sometime after 750 kg of xenon propellant throughput; well beyond the mission-derived lifetime requirement. The NEXT wear test data confirm that the erosion of the discharge keeper orifice, enlarging of nominal-current-density accelerator grid aperture cusps, and the decrease in cold grid-gap observed during the NSTAR Extended Life Test have been mitigated. This paper presents the status of the NEXT LDT to date.

Estimation of Rain Intensity Spectra over the Continental US Using Ground Radar-Gauge Measurements

NASA Technical Reports Server (NTRS)

Lin, Xin; Hou, Arthur Y.

2013-01-01

A high-resolution surface rainfall product is used to estimate rain characteristics over the continental US as a function of rain intensity. By defining each data at 4-km horizontal resolutions and 1-h temporal resolutions as an individual precipitating/nonprecipitating sample, statistics of rain occurrence and rain volume including their geographical and seasonal variations are documented. Quantitative estimations are also conducted to evaluate the impact of missing light rain events due to satellite sensors' detection capabilities. It is found that statistics of rain characteristics have large seasonal and geographical variations across the continental US. Although heavy rain events (> 10 mm/hr.) only occupy 2.6% of total rain occurrence, they may contribute to 27% of total rain volume. Light rain events (< 1.0 mm/hr.), occurring much more frequently (65%) than heavy rain events, can also make important contributions (15%) to the total rain volume. For minimum detectable rain rates setting at 0.5 and 0.2 mm/hr which are close to sensitivities of the current and future space-borne precipitation radars, there are about 43% and 11% of total rain occurrence below these thresholds, and they respectively represent 7% and 0.8% of total rain volume. For passive microwave sensors with their rain pixel sizes ranging from 14 to 16 km and the minimum detectable rain rates around 1 mm/hr., the missed light rain events may account for 70% of train occurrence and 16% of rain volume. Statistics of rain characteristics are also examined on domains with different temporal and spatial resolutions. Current issues in estimates of rain characteristics from satellite measurements and model outputs are discussed.

Alternating steady state free precession for estimation of current-induced magnetic flux density: A feasibility study.

PubMed

Lee, Hyunyeol; Jeong, Woo Chul; Kim, Hyung Joong; Woo, Eung Je; Park, Jaeseok

2016-05-01

To develop a novel, current-controlled alternating steady-state free precession (SSFP)-based conductivity imaging method and corresponding MR signal models to estimate current-induced magnetic flux density (Bz ) and conductivity distribution. In the proposed method, an SSFP pulse sequence, which is in sync with alternating current pulses, produces dual oscillating steady states while yielding nonlinear relation between signal phase and Bz . A ratiometric signal model between the states was analytically derived using the Bloch equation, wherein Bz was estimated by solving a nonlinear inverse problem for conductivity estimation. A theoretical analysis on the signal-to-noise ratio of Bz was given. Numerical and experimental studies were performed using SSFP-FID and SSFP-ECHO with current pulses positioned either before or after signal encoding to investigate the feasibility of the proposed method in conductivity estimation. Given all SSFP variants herein, SSFP-FID with alternating current pulses applied before signal encoding exhibits the highest Bz signal-to-noise ratio and conductivity contrast. Additionally, compared with conventional conductivity imaging, the proposed method benefits from rapid SSFP acquisition without apparent loss of conductivity contrast. We successfully demonstrated the feasibility of the proposed method in estimating current-induced Bz and conductivity distribution. It can be a promising, rapid imaging strategy for quantitative conductivity imaging. © 2015 Wiley Periodicals, Inc.

Total Dissolved Gas Effects on Fishes of the Lower Columbia River

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

McGrath, Kathy E.; Dawley, Earl; Geist, David R.

2006-03-31

Gas supersaturation problems generated by spill from dams on the Columbia River were first identified in the 1960s. Since that time, considerable research has been conducted on effects of gas supersaturation on aquatic life, primarily juvenile salmonids. Also since that time, modifications to dam structures and operations have reduced supersaturated gas levels produced by the dams. The limit for total dissolved gas saturation (TDGS) as mandated by current Environmental Protection Agency water quality standards is 110%. State management agencies issue limited waivers to water quality, allowing production of levels of up to 120% TDGS to facilitate the downstream migration ofmore » juvenile salmonids. Recently, gas supersaturation as a water quality issue has resurfaced as concerns have grown regarding chronic effects of spill-related total dissolved gas on salmonids, including incubating embryos and larvae, resident fish species, and other aquatic organisms. Because of current concerns, and because the last comprehensive review of research on supersaturation effects on fishes was conducted in 1997, we reviewed recent supersaturation literature to identify new or ongoing issues that may not be adequately addressed by the current 110% TDGS limit and the 120% TDGS water quality waiver. We found that recent work supports older research indicating that short-term exposure to levels up to 120% TDGS does not produce acute effects on migratory juvenile or adult salmonids when compensating depths are available. Monitoring programs at Snake and Columbia river dams from 1995 to the early 2000s documented a low incidence of significant gas bubble disease or mortality in Columbia River salmonids, resident fishes, or other taxa. We did, however, identify five areas of concern in which total dissolved gas levels lower than water quality limits may produce sublethal effects on fishes of the Columbia River. These areas of concern are 1) sensitive and vulnerable species or life stages, 2) long-term chronic or multiple exposure, 3) vulnerable habitats and reaches, 4) effects on incubating fish in hyporheic habitats, and 5) community and ecosystem effects. Although some of these areas of concern may have been identified previously in earlier works, we suggest that consideration of the issues is warranted to avoid detrimental impacts on aquatic resources of the Columbia River system. We discuss these issues and provide recommendations to regulatory and management agencies based on our review of recent literature. In general, we recommend that additional attention be directed toward resolving the uncertainties within these five areas.« less

Coherent radar estimates of high latitude field-aligned currents: the importance of conductance gradients

NASA Astrophysics Data System (ADS)

Kosch, M.; Nielsen, E.

Two bi-static VHF radar systems STARE and SABRE have been employed to estimate ionospheric electric field distributions in the geomagnetic latitude range 61 1 - 69 3 degrees over Scandinavia corresponding to the global Region 2 current system 173 days of data from all four radars have been analysed during the period 1982 to 1986 The average magnetic field-aligned currents have been computed as a function of the Kp and Ae indices using an empirical model of ionospheric Pedersen and Hall conductance taking into account conductance gradients The divergence of horizontal Pedersen currents and Hall conductance gradients have approximately the same importance for generating the Region 2 field-aligned currents Pedersen conductance gradients have a significant modifying effect A case study of field-aligned currents has been performed using the STARE radar system to obtain the instantaneous ionospheric electric field distribution in the vicinity of an auroral arc The instantaneous Hall conductance was estimated from the Scandinavian Magnetometer Array This study clearly shows that even for quiet steady state geomagnetic conditions conductance gradients are important modifiers of magnetic field-aligned currents

Sweet bee venom pharmacopuncture for chemotherapy-induced peripheral neuropathy.

PubMed

Yoon, Jeungwon; Jeon, Ju-Hyun; Lee, Yeon-Weol; Cho, Chong-Kwan; Kwon, Ki-Rok; Shin, Ji-Eun; Sagar, Stephen; Wong, Raimond; Yoo, Hwa-Seung

2012-08-01

Chemotherapy-induced peripheral neuropathy (CIPN) is sensory and motor nerve damage to the peripheral nervous system caused by chemotherapeutic agents. It often causes pain and other varying degrees of neuropathic symptoms accompanied by functional limitations and reduced quality of life. Currently, there is no standard treatment protocol for the treatment of CIPN. In need of more research to develop new therapeutic options focusing on their safety, efficacy, and long-term sustained clinical effects, a pilot study of sweet bee venom pharmacopuncture (SBVP) for CIPN was conducted to build up preliminary efficacy data in the process of preparing for a future larger scale randomized controlled SBVP trial for CIPN. We conducted a prospective case series by analyzing the clinical observations made of CIPN patients treated with SBVP. A total of 11 eligible consecutive CIPN patients who visited East-West Cancer Center from June 1, 2010, to February 28, 2011, were treated with total of six SBVP treatments given within the 3-week period. The outcomes were measured using World Health Organization Common Toxicity Criteria for Peripheral neuropathy (WHO grading system), Patient Neurotoxicity Questionnaire (PNQ), Visual Analogue System (VAS), and Health-Related Quality of Life (HRQOL) collected at the baseline, post-second, fourth, and the final treatment. Patients were followed 3 weeks into no intervention to determine the sustained effects of pharmacopuncture. Both of the WHO CIPN grade and PNQ scores have shown a decrease in the level of neuropathy. VAS pain level has also shown a great decrease and improvement in patients' quality of life have also been detected though modest. Changes in WHO grade, VAS and Total HRQOL scores between the baseline and after the last treatment session were significant. Changes in WHO grade, Total PNQ, PNQ-sensory, VAS, Total HRQOL, and HRQOL-functional scores between the baseline and the 3-week follow-up were significant. The positive result of the study supports the potential value of conducting a fully powered trial to explore further efficacy of SBVP for CIPN. However a single positive result within this pilot study must be interpreted with caution. Copyright © 2012. Published by Elsevier B.V.

Comparison of approaches to Total Quality Management. Including an examination of the Department of Energy`s position on quality management

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

Bennett, C.T.

1994-03-01

This paper presents a comparison of several qualitatively different approaches to Total Quality Management (TQM). The continuum ranges from management approaches that are primarily standards -- with specific guidelines, but few theoretical concepts -- to approaches that are primarily philosophical, with few specific guidelines. The approaches to TQM discussed in this paper include the International Organization for Standardization (ISO) 9000 Standard, the Malcolm Baldrige National Quality Award, Senge`s the Learning Organization, Watkins and Marsick`s approach to organizational learning, Covey`s Seven Habits of Highly Successful People, and Deming`s Fourteen Points for Management. Some of these approaches (Deming and ISO 9000) aremore » then compared to the DOE`s official position on quality management and conduct of operations (DOE Orders 5700.6C and 5480.19). Using a tabular format, it is shown that while 5700.6C (Quality Assurance) maps well to many of the current approaches to TQM, DOE`s principle guide to management Order 5419.80 (Conduct of Operations) has many significant conflicts with some of the modern approaches to continuous quality improvement.« less

Aerial Radiological Survey of Abandoned Uranium Mines (AUM) Map Service, Navajo Nation, 1994-1999, US EPA Region 9

EPA Pesticide Factsheets

This map service contains data from aerial radiological surveys of 41 potential uranium mining areas (1,144 square miles) within the Navajo Nation that were conducted during the period from October 1994 through October 1999. The US Environmental Protection Agency (USEPA) Region 9 funded the surveys and the US Department of Energy (USDOE) Remote Sensing Laboratory (RSL) in Las Vegas, Nevada conducted the aerial surveys. The aerial survey data were used to characterize the overall radioactivity and excess Bismuth 214 levels within the surveyed areas.This US EPA Region 9 web service contains the following map layers: Total Terrestrial Gamma Activity Polygons, Total Terrestrial Gamma Activity Contours, Excess Bismuth 214 Contours, Excess Bismuth 214 Polygons, Flight AreasFull FGDC metadata records for each layer can be found by clicking the layer name at the web service endpoint and viewing the layer description.Security Classification: Public. Access Constraints: None. Use Constraints: None. Please check sources, scale, accuracy, currentness and other available information. Please confirm that you are using the most recent copy of both data and metadata. Acknowledgement of the EPA would be appreciated.

Mixed Messages: Ambiguous Penalty Information in Modified Restaurant Menu Items

PubMed Central

Lawless, Harry T.; Patel, Anjali A.; Lopez, Nanette V.

2016-01-01

Restaurant menu items from six national or regional brands were modified to reduce fat, saturated fat, sodium and total calories. Twenty-four items were tested with a current recipe, and two modifications (small and moderate reductions) for 72 total products. Approximately 100 consumers tested each product for acceptability as well as for desired levels of tastes/flavor, amounts of key ingredients and texture/consistency using just-about-right (JAR) scales. Penalty analysis was conducted to assess the effects of non-JAR ratings on acceptability scores. Situations arose where JAR ratings and penalty analyses could yield different recommendations, including large groups with low penalties and small groups with high penalties. Opposing groups with moderate to high penalties on opposite sides of the same JAR scale were also seen. Strategies for dealing with these observances are discussed. PMID:27833254

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

Menon, R.; Grames, L.M.

Pilot Carrousel testing was conducted for about three months on wastewaters generated at a major potato processing facility in 1993. The testing focused toward removal of BOD, NH{sub 3} and NO{sub 3}, and Total-P. After five-six weeks that it took for the system to reach steady state operation, the pilot plant was able to treat the wastewaters quite well. Effluent BOD{sub 5} and TKN values were less than 8 and 4 mg/L, respectively, during the second half of testing. Total-P in the effluent was less than 10 mg/L, although this step was not optimized. Based on the pilot testing, amore » full-scale Carrousel activated sludge plant was designed and commissioned in 1994. This plant is currently treating all the wastewaters from the facility and performing contaminant removals at a very high level.« less

Measuring skin conductance over clothes.

PubMed

Hong, Ki Hwan; Lee, Seung Min; Lim, Yong Gyu; Park, Kwang Suk

2012-11-01

We propose a new method that measures skin conductance over clothes to nonintrusively monitor the changes in physiological conditions affecting skin conductance during daily activities. We selected the thigh-to-thigh current path and used an indirectly coupled 5-kHz AC current for the measurement. While varying the skin conductance by the Valsalva maneuver method, the results were compared with the traditional galvanic skin response (GSR) measured directly from the fingers. Skin conductance measured using a 5-kHz current displayed a highly negative correlation with the traditional GSR and the current measured over clothes reflected the rate of change of the conductance of the skin beneath.

Electronic tunneling through a fullerene-like molecular bridge

NASA Astrophysics Data System (ADS)

Vanaie, H.; Yaghobi, M.

2018-04-01

This study was conducted to consider the electronic transport properties of the N_{36} B_{36} molecule, using the Green's function method based on the GW model. The number, width, height and position of density of state peaks are dramatically dependent on the correlation effect, the contact type and symmetric properties of the molecule. Also, negative differential resistance behavior was observed for all modes in voltages 4.4 V (- 4.5 V) to 4.7 V (- 4.7 V). The N_{36} B_{36} molecule behaves as an insulator where the total current becomes zero for the same values of the gate voltages but acts as a metal at other values. Therefore, the physical picture of electron conduction may change in N_{36} B_{36}—based molecular devices and it could behave as a semiconductor.

Common Coding Variants in SCN10A Are Associated With the Nav1.8 Late Current and Cardiac Conduction.

PubMed

Macri, Vincenzo; Brody, Jennifer A; Arking, Dan E; Hucker, William J; Yin, Xiaoyan; Lin, Honghuang; Mills, Robert W; Sinner, Moritz F; Lubitz, Steven A; Liu, Ching-Ti; Morrison, Alanna C; Alonso, Alvaro; Li, Ning; Fedorov, Vadim V; Janssen, Paul M; Bis, Joshua C; Heckbert, Susan R; Dolmatova, Elena V; Lumley, Thomas; Sitlani, Colleen M; Cupples, L Adrienne; Pulit, Sara L; Newton-Cheh, Christopher; Barnard, John; Smith, Jonathan D; Van Wagoner, David R; Chung, Mina K; Vlahakes, Gus J; O'Donnell, Christopher J; Rotter, Jerome I; Margulies, Kenneth B; Morley, Michael P; Cappola, Thomas P; Benjamin, Emelia J; Muzny, Donna; Gibbs, Richard A; Jackson, Rebecca D; Magnani, Jared W; Herndon, Caroline N; Rich, Stephen S; Psaty, Bruce M; Milan, David J; Boerwinkle, Eric; Mohler, Peter J; Sotoodehnia, Nona; Ellinor, Patrick T

2018-05-01

Genetic variants at the SCN5A / SCN10A locus are strongly associated with electrocardiographic PR and QRS intervals. While SCN5A is the canonical cardiac sodium channel gene, the role of SCN10A in cardiac conduction is less well characterized. We sequenced the SCN10A locus in 3699 European-ancestry individuals to identify variants associated with cardiac conduction, and replicated our findings in 21,000 individuals of European ancestry. We examined association with expression in human atrial tissue. We explored the biophysical effect of variation on channel function using cellular electrophysiology. We identified 2 intronic single nucleotide polymorphisms in high linkage disequilibrium ( r   2 =0.86) with each other to be the strongest signals for PR (rs10428132, β=-4.74, P =1.52×10 -14 ) and QRS intervals (rs6599251, QRS β=-0.73; P =1.2×10 -4 ), respectively. Although these variants were not associated with SCN5A or SCN10A expression in human atrial tissue (n=490), they were in high linkage disequilibrium ( r   2 ≥0.72) with a common SCN10A missense variant, rs6795970 (V1073A). In total, we identified 7 missense variants, 4 of which (I962V, P1045T, V1073A, and L1092P) were associated with cardiac conduction. These 4 missense variants cluster in the cytoplasmic linker of the second and third domains of the SCN10A protein and together form 6 common haplotypes. Using cellular electrophysiology, we found that haplotypes associated with shorter PR intervals had a significantly larger percentage of late current compared with wild-type (I962V+V1073A+L1092P, 20.2±3.3%, P =0.03, and I962V+V1073A, 22.4±0.8%, P =0.0004 versus wild-type 11.7±1.6%), and the haplotype associated with the longest PR interval had a significantly smaller late current percentage (P1045T, 6.4±1.2%, P =0.03). Our findings suggest an association between genetic variation in SCN10A , the late sodium current, and alterations in cardiac conduction. © 2018 American Heart Association, Inc.

Performance Evaluation of Titanium Ion Optics for the NASA 30 cm Ion Thruster

NASA Technical Reports Server (NTRS)

Soulas, George C.

2001-01-01

The results of performance tests with titanium ion optics were presented and compared to those of molybdenum ion optics. Both titanium and molybdenum ion optics were initially operated until ion optics performance parameters achieved steady state values. Afterwards, performance characterizations were conducted. This permitted proper performance comparisons of titanium and molybdenum ion optics. Ion optics' performance A,as characterized over a broad thruster input power range of 0.5 to 3.0 kW. All performance parameters for titanium ion optics of achieved steady state values after processing 1200 gm of propellant. Molybdenum ion optics exhibited no burn-in. Impingement-limited total voltages for titanium ion optics where up to 55 V greater than those for molybdenum ion optics. Comparisons of electron backstreaming limits as a function of peak beam current density for molybdenum and titanium ion optics demonstrated that titanium ion optics operated with a higher electron backstreaming limit than molybdenum ion optics for a given peak beam current density. Screen grid ion transparencies for titanium ion optics were as much as 3.8 percent lower than those for molybdenum ion optics. Beam divergence half-angles that enclosed 95 percent of the total beam current for titanium ion optics were within 1 to 3 deg. of those for molybdenum ion optics. All beam divergence thrust correction factors for titanium ion optics were within 1 percent of those with molybdenum ion optics.

Electric thruster research

NASA Technical Reports Server (NTRS)

Kaufman, H. R.; Robinson, R. S.

1982-01-01

It has been customary to assume that ions flow nearly equally in all directions from the ion production region within an electron-bombardment discharge chamber. In general, the electron current through a magnetic field can alter the electron density, and hence the ion density, in such a way that ions tend to be directed away from the region bounded by the magnetic field. When this mechanism is understood, it becomes evident that many past discharge chamber designs have operated with a preferentially directed flow of ions. Thermal losses were calculated for an oxide-free hollow cathode. At low electron emissions, the total of the radiation and conduction losses agreed with the total discharge power. At higher emissions, though, the plasma collisions external to the cathode constituted an increasingly greater fraction of the discharge power. Experimental performance of a Hall-current thruster was adversely affected by nonuniformities in the magnetic field, produced by the cathode heating current. The technology of closed-drift thrusters was reviewed. The experimental electron diffusion in the acceleration channel was found to be within about a factor of 3 of the Bohm value for the better thruster designs at most operating conditions. Thruster efficiencies of about 0.5 appear practical for the 1000 to 2000 s range of specific impulse. Lifetime information is limited, but values of several thousands of hours should be possible with anode layer thrusters operated or = to 2000 s.

Development of eddy current microscopy for high resolution electrical conductivity imaging using atomic force microscopy.

PubMed

Nalladega, V; Sathish, S; Jata, K V; Blodgett, M P

2008-07-01

We present a high resolution electrical conductivity imaging technique based on the principles of eddy current and atomic force microscopy (AFM). An electromagnetic coil is used to generate eddy currents in an electrically conducting material. The eddy currents generated in the conducting sample are detected and measured with a magnetic tip attached to a flexible cantilever of an AFM. The eddy current generation and its interaction with the magnetic tip cantilever are theoretically modeled using monopole approximation. The model is used to estimate the eddy current force between the magnetic tip and the electrically conducting sample. The theoretical model is also used to choose a magnetic tip-cantilever system with appropriate magnetic field and spring constant to facilitate the design of a high resolution electrical conductivity imaging system. The force between the tip and the sample due to eddy currents is measured as a function of the separation distance and compared to the model in a single crystal copper. Images of electrical conductivity variations in a polycrystalline dual phase titanium alloy (Ti-6Al-4V) sample are obtained by scanning the magnetic tip-cantilever held at a standoff distance from the sample surface. The contrast in the image is explained based on the electrical conductivity and eddy current force between the magnetic tip and the sample. The spatial resolution of the eddy current imaging system is determined by imaging carbon nanofibers in a polymer matrix. The advantages, limitations, and applications of the technique are discussed.

Mortality After Total Knee and Total Hip Arthroplasty in a Large Integrated Health Care System.

PubMed

Inacio, Maria C S; Dillon, Mark T; Miric, Alex; Navarro, Ronald A; Paxton, Elizabeth W

2017-01-01

The number of excess deaths associated with elective total joint arthroplasty in the US is not well understood. To evaluate one-year postoperative mortality among patients with elective primary and revision arthroplasty procedures of the hip and knee. A retrospective analysis was conducted of hip and knee arthroplasties performed in 2010. Procedure type, procedure volume, patient age and sex, and mortality were obtained from an institutional total joint replacement registry. An integrated health care system population was the sampling frame for the study subjects and was the reference group for the study. Standardized 1-year mortality ratios (SMRs) and 95% confidence intervals (CIs) were calculated. A total of 10,163 primary total knee arthroplasties (TKAs), 4963 primary total hip arthroplasties (THAs), 606 revision TKAs, and 496 revision THAs were evaluated. Patients undergoing primary THA (SMR = 0.6, 95% CI = 0.4-0.7) and TKA (SMR = 0.4, 95% CI = 0.3-0.5) had lower odds of mortality than expected. Patients with revision TKA had higher-than-expected mortality odds (SMR = 1.8, 95% CI = 1.1-2.5), whereas patients with revision THA (SMR = 0.9, 95% CI = 0.4-1.5) did not have higher-than-expected odds of mortality. Understanding excess mortality after joint surgery allows clinicians to evaluate current practices and to determine whether certain groups are at higher-than-expected mortality risk after surgery.

Worksite adjustments and work ability among employed cancer survivors.

PubMed

Torp, Steffen; Nielsen, Roy A; Gudbergsson, Sævar B; Dahl, Alv A

2012-09-01

This study was conducted to determine how many cancer survivors (CSs) make worksite adjustments and what kinds of adjustments they make. Changes in work ability among employed CSs were explored, and clinical, sociodemographic, and work-related factors associated with the current total work ability were studied. CSs of the ten most common invasive types of cancer for men and women in Norway completed a mailed questionnaire 15-39 months after being diagnosed with cancer. Included in the analyses were all participants who worked both at the time of diagnosis and at the time of the survey and who had not changed their labor force status since diagnosis (n = 563). The current total work ability was compared to the lifetime best (0-10 score). Twenty-six percent of the employed CSs had made adjustments at work, and the most common adjustment was changing the number of work hours per week. Despite the fact that 31% and 23% reported reduced physical and mental work abilities, respectively, more than 90% of the CSs reported that they coped well with their work demands. The mean total work ability score was high (8.6) among both men and women. Being self-employed and working part-time at the time of diagnosis showed significant negative correlations with total work ability, while a favorable psychosocial work environment showed a significant positive correlation. CSs with low work ability were more often in contact with the occupational health service and also made more worksite adjustments than others. The prospects of future work life seem optimistic for Norwegian employed CSs who return to work relatively soon after primary treatment.

Contaminants in fishes from great lakes-influenced sections and above dams of three Michigan Rivers: III. Implications for health of bald eagles

USGS Publications Warehouse

Giesy, J.P.; Bowerman, W.W.; Mora, M.A.; Verbrugge, D.A.; Othoudt, R. A.; Newsted, J.L.; Summer, C. L.; Aulerich, R.J.; Bursian, S.J.; Ludwig, J. P.; Dawson, G. A.; Kubiak, T.J.; Best, D. A.; Tillitt, D. E.

1995-01-01

Recently, there have been discussions of the relative merits of passage of fishes around hydroelectric dams on three rivers (Au Sable, Manistee, and Muskegon) in Michigan. A hazard assessment was conducted to determine the potential for adverse effects on bald eagles that could consume such fishes from above and below dams on the three primary rivers. The hazard assessments were verified by comparing the reproductive productivities of eagles nesting in areas where they ate primarily fish from either above or below dams on the three primary rivers, as well as on two additional rivers in Michigan, the Menominee and Thunder Bay. Concentrations of organochlorine insecticides (OCI), polychlorinated biphenyls (total PCBs), 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TCDD-EQ), and total mercury (Hg) were measured in composite samples of fishes from above and below hydroelectric dams on the Manistee and Muskegon Rivers, which flow into Lake Michigan, and the Au Sable River, which flows into Lake Huron. Mean concentrations of OCI, total PCBs, and TCDD-EQ were all greater in fishes from below the dams than in those from above. The hazard assessment indicated that current concentrations of Hg and OCI other than DDT (DDT + DDE + DDD) in fish from neither above nor below dams would present a significant hazard to bald eagles (Haliaeetus leucocephalus). Both total PCBs and TCDD-EQ in fishes from below the dams currently present a significant hazard to bald eagles, since their mean hazard quotients (HQ) were all greater than one.

Expenditure and resource utilisation for cervical screening in Australia

PubMed Central

2012-01-01

Background The National Cervical Screening Program in Australia currently recommends that women aged 18–69 years are screened with conventional cytology every 2 years. Publicly funded HPV vaccination was introduced in 2007, and partly as a consequence, a renewal of the screening program that includes a review of screening recommendations has recently been announced. This study aimed to provide a baseline for such a review by quantifying screening program resource utilisation and costs in 2010. Methods A detailed model of current cervical screening practice in Australia was constructed and we used data from the Victorian Cervical Cytology Registry to model age-specific compliance with screening and follow-up. We applied model-derived rate estimates to the 2010 Australian female population to calculate costs and numbers of colposcopies, biopsies, treatments for precancer and cervical cancers in that year, assuming that the numbers of these procedures were not yet substantially impacted by vaccination. Results The total cost of the screening program in 2010 (excluding administrative program overheads) was estimated to be A$194.8M. We estimated that a total of 1.7 million primary screening smears costing $96.7M were conducted, a further 188,900 smears costing $10.9M were conducted to follow-up low grade abnormalities, 70,900 colposcopy and 34,100 histological evaluations together costing $21.2M were conducted, and about 18,900 treatments for precancerous lesions were performed (including retreatments), associated with a cost of $45.5M for treatment and post-treatment follow-up. We also estimated that $20.5M was spent on work-up and treatment for approximately 761 women diagnosed with invasive cervical cancer. Overall, an estimated $23 was spent in 2010 for each adult woman in Australia on cervical screening program-related activities. Conclusions Approximately half of the total cost of the screening program is spent on delivery of primary screening tests; but the introduction of HPV vaccination, new technologies, increasing the interval and changing the age range of screening is expected to have a substantial impact on this expenditure, as well as having some impact on follow-up and management costs. These estimates provide a benchmark for future assessment of the impact of changes to screening program recommendations to the costs of cervical screening in Australia. PMID:23216968

A novel eco-friendly technique for efficient control of lime water softening process.

PubMed

Ostovar, Mohamad; Amiri, Mohamad

2013-12-01

Lime softening is an established type of water treatment used for water softening. The performance of this process is highly dependent on lime dosage. Currently, lime dosage is adjusted manually based on chemical tests, aimed at maintaining the phenolphthalein (P) and total (M) alkalinities within a certain range (2 P - M > or = 5). In this paper, a critical study of the softening process has been presented. It has been shown that the current method is frequently incorrect. Furthermore, electrical conductivity (EC) has been introduced as a novel indicator for effectively characterizing the lime softening process.This novel technique has several advantages over the current alkalinities method. Because no chemical reagents are needed for titration, which is a simple test, there is a considerable reduction in test costs. Additionally, there is a reduction in the treated water hardness and generated sludge during the lime softening process. Therefore, it is highly eco-friendly, and is a very cost effective alternative technique for efficient control of the lime softening process.

Electrical Current Leakage and Open-Core Threading Dislocations in AlGaN-Based Deep Ultraviolet Light-Emitting Diodes.

DOE PAGES

Moseley, Michael William; Allerman, Andrew A.; Crawford, Mary H.; ...

2014-08-04

Electrical current transport through leakage paths in AlGaN-based deep ultraviolet (DUV) lightemitting diodes (LEDs) and their effect on LED performance are investigated. Open-core threading dislocations, or nanopipes, are found to conduct current through nominally insulating Al0.7Ga0.3N layers and limit the performance of DUV-LEDs. A defect-sensitive phosphoric acid etch reveals these opencore threading dislocations in the form of large, micron-scale hexagonal etch pits visible with optical microscopy, while closed-core screw-, edge-, and mixed-type threading dislocations are represented by smaller and more numerous nanometer-scale pits visible by atomic-force microscopy. The electrical and optical performances of DUV-LEDs fabricated on similar Si-doped Al0.7Ga0.3N templatesmore » are found to have a strong correlation to the density of these nanopipes, despite their small fraction (<0.1% in this study) of the total density of threading dislocations.« less

Single-stage three-phase boost power factor correction circuit for AC-DC converter

NASA Astrophysics Data System (ADS)

Azazi, Haitham Z.; Ahmed, Sayed M.; Lashine, Azza E.

2018-01-01

This article presents a single-stage three-phase power factor correction (PFC) circuit for AC-to-DC converter using a single-switch boost regulator, leading to improve the input power factor (PF), reducing the input current harmonics and decreasing the number of required active switches. A novel PFC control strategy which is characterised as a simple and low-cost control circuit was adopted, for achieving a good dynamic performance, unity input PF, and minimising the harmonic contents of the input current, at which it can be applied to low/medium power converters. A detailed analytical, simulation and experimental studies were therefore conducted. The effectiveness of the proposed controller algorithm is validated by the simulation results, which were carried out using MATLAB/SIMULINK environment. The proposed system is built and tested in the laboratory using DSP-DS1104 digital control board for an inductive load. The results revealed that the total harmonic distortion in the supply current was very low. Finally, a good agreement between simulation and experimental results was achieved.

80 MeV C{sup 6+} ion irradiation effects on the DC electrical characteristics of silicon NPN power transistors

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

Bharathi, M. N.; Vinayakprasanna, N. H.; Prakash, A. P. Gnana, E-mail: gnanaprakash@physics.uni-mysore.ac.in

The total dose effects of 80 MeV C{sup 6+} ions on the DC electrical characteristics of Silicon NPN rf power transistors have been studied in the dose range of 100 krad to 100 Mrad. The SRIM simulation was used to understand the energy loss and range of the ions in the transistor structure. The different electrical parameters such as Gummel characteristics, excess base current (ΔI{sub B} = I{sub Bpost} - I{sub Bpre}), dc forward current gain (h{sub FE}), transconductance (g{sub m}), displacement damage factor (K) and output characteristics (V{sub CE}-I{sub C}) were studied systematically before and after irradiation. The significantmore » degradation in base current (I{sub B}) and h{sub FE} was observed after irradiation. Isochronal annealing study was conducted on the irradiated transistors to analyze the recovery in different electrical parameters. These results were compared with {sup 60}C0 gamma irradiation results in the same dose range.« less

First-principles study on leakage current caused by oxygen vacancies at HfO2/SiO2/Si interface

NASA Astrophysics Data System (ADS)

Takagi, Kensuke; Ono, Tomoya

2018-06-01

The relationship between the position of oxygen vacancies in HfO2/SiO2/Si gate stacks and the leakage current is studied by first-principles electronic-structure and electron-conduction calculations. We find that the increase in the leakage current due to the creation of oxygen vacancies in the HfO2 layer is much larger than that in the SiO2 interlayer. According to previous first-principles total energy calculations, the formation energy of oxygen vacancies is smaller in the SiO2 interlayer than that in the HfO2 layer under the same conditions. Therefore, oxygen vacancies will be attracted from the SiO2 interlayer to minimize the energy, thermodynamically justifying the scavenging technique. Thus, the scavenging process efficiently improves the dielectric constant of HfO2-based gate stacks without increasing the number of oxygen vacancies, which cause the dielectric breakdown.

Rocket observations at the northern edge of the eastward electrojet

NASA Technical Reports Server (NTRS)

Cahill, L. J., Jr.; Arnoldy, R. L.; Taylor, W. W. L.

1980-01-01

The paper discusses a Nike-Tomahawk rocket launched north over quiet, late evening auroral arcs in March 1975. A northward magnetic disturbance was observed on the ground under the rocket trajectory; south of the arcs the northward electric field was 60 mV/m, indicating strong westward plasma flow. An eastward electrojet current layer was penetrated in the upward flight, and precipitating electrons were observed over each arc. Using the observed electron flux and a model of the ionosphere, the Hall and Pedersen conductivities were calculated which were used to compute the eastward and northward components of the horizontal ionospheric currents. The joule power decreased abruptly in the auroral arcs, as the precipitating electron power increased; the total dissipated power was the same inside the arcs, between them and southward. North of the aurora the electric field and dissipated power remained low; field-aligned currents carried by the observed electrons were about a factor of 3 lower than those inferred from the magnetic field measurements.

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.

Evaluation of current operating standards for chlorine dioxide in disinfection of dump tank and flume for fresh tomatoes.

PubMed

Tomás-Callejas, Alejandro; López-Velasco, Gabriela; Valadez, Angela M; Sbodio, Adrian; Artés-Hernández, Francisco; Danyluk, Michelle D; Suslow, Trevor V

2012-02-01

Standard postharvest unit operations that rely on copious water contact, such as fruit unloading and washing, approach the criteria for a true critical control point in fresh tomato production. Performance data for approved sanitizers that reflect commercial systems are needed to set standards for audit compliance. This study was conducted to evaluate the efficacy of chlorine dioxide (ClO(2)) for water disinfection as an objective assessment of recent industry-adopted standards for dump tank and flume management in fresh tomato packing operations. On-site assessments were conducted during eight temporally distinct shifts in two Florida packinghouses and one California packinghouse. Microbiological analyses of incoming and washed fruit and dump and flume system water were evaluated. Water temperature, pH, turbidity, conductivity, and oxidation-reduction potential (ORP) were monitored. Reduction in populations of mesophilic and coliform bacteria on fruit was not significant, and populations were significantly higher (P < 0.05) after washing. Escherichia coli was near the limit of detection in dump tanks but consistently below the detection limit in flumes. Turbidity and conductivity increased with loads of incoming tomatoes. Water temperature varied during daily operations, but pH and ORP mostly remained constant. The industry standard positive temperature differential of 5.5°C between water and fruit pulp was not maintained in tanks during the full daily operation. ORP values were significantly higher in the flume than in the dump tank. A positive correlation was found between ORP and temperature, and negative correlations were found between ORP and turbidity, total mesophilic bacteria, and coliforms. This study provides in-plant data indicating that ClO(2) can be an effective sanitizer in flume and spray-wash systems, but current operational limitations restrict its performance in dump tanks. Under current conditions, ClO(2) alone is unlikely to allow the fresh tomato industry to meet its microbiological quality goals under typical commercial conditions.

Bariatric manipulation of gastric arteries: A systematic review on the potential concept for treatment of obesity.

PubMed

Shoar, Saeed; Saber, Alan A; Aladdin, Mohammaed; Bashah, Moataz M; AlKuwari, Mohammed J; Rizwan, Mohamed; Rosenthal, Raul J

2016-12-01

Gastric artery embolization (GAE) has recently received attention as a minimally invasive intervention in bariatric setting. The current systematic review aimed to gather and categorizes the existing data in the literature regarding bariatric gastric artery manipulation. This will highlight the importance of this potential concept as a therapeutic modality. A PubMed/Medline search was conducted to identify animal and human studies investigating the effect of gastric artery manipulation on weight, ghrelin, obesity, and tissue adiposity. A total of 9 studies including 6 animal experiments with 71 subjects and 3 human studies with a total of 25 patients were retrieved. Animal subjects underwent chemical embolization while particle embolization was only used in human subjects. Five animal studies and 1 human study reported decreased ghrelin concentration. Three animal experiments and 2 human studies showed a significant weight change following GAE. There was no report regarding a serious adverse event requiring surgical or interventional management. Currently, data regarding the potential role of gastric artery manipulation in decreasing the ghrelin and potential weight loss is scarce. Copyright © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Improving Evidence Dissemination and Accessibility through a Mobile-based Resource Platform.

PubMed

Zhu, Zheng; Xing, Weijie; Hu, Yan; Zhou, Yingfeng; Gu, Ying

2018-05-28

Current mobile information technologies fundamentally influence evidence dissemination from the perspective of both evidence seekers and evidence providers. However, there is no related study which tried using a mobile-based platform to disseminate evidence in China. The main object of this study is to develop a mobile-based evidence resource platform and to evaluate its effects of improving nurses' access to evidence-based practice resources and meeting users' demands. The mobile-based evidence resource platform was developed in 2014. A cross-sectional study was conducted over a period of 2 months between December 2015 and January 2016 to evaluate user experiences of and preferences regarding the platform. Descriptive analysis was adopted to analyze information and its communication effects from December 2014 to March 2017. A total of 472 participants met the inclusion criteria and responded to the survey. High scores were received for the overall rating (4.34 ± 0.67), evidence section (4.30 ± 0.63), learning materials section (4.26 ± 0.65), news section (4.27 ± 0.66), readability (4.38 ± 0.63), design and structure (4.38 ± 0.63), and interactivity (3.58 ± 0.84). As of March 31, 2017, the total number of followers was 28,954. The total number of readings was 584,834. The most current WCI value was 388.72. Our study demonstrated that the mobile-based platform for evidence transfer can promote the accessibility of evidence and meet users' demands. This mobile-based platform is currently available in the WeChat application environment. It will be a wise option for healthcare professionals for the purposes of learning about EBP and disseminating evidence in China.

3D near-to-surface conductivity reconstruction by inversion of VETEM data using the distorted Born iterative method

USGS Publications Warehouse

Wang, G.L.; Chew, W.C.; Cui, T.J.; Aydiner, A.A.; Wright, D.L.; Smith, D.V.

2004-01-01

Three-dimensional (3D) subsurface imaging by using inversion of data obtained from the very early time electromagnetic system (VETEM) was discussed. The study was carried out by using the distorted Born iterative method to match the internal nonlinear property of the 3D inversion problem. The forward solver was based on the total-current formulation bi-conjugate gradient-fast Fourier transform (BCCG-FFT). It was found that the selection of regularization parameter follow a heuristic rule as used in the Levenberg-Marquardt algorithm so that the iteration is stable.

Current distribution and status of Himalayan ibex in upper Neelum Valley, District Neelum Azad Jammu and Kashmir, Pakistan.

PubMed

Ali, Usman; Ahmed, Khawaja Bashrat; Awan, Muhammad Siddique; Asraf, Shaid; Basher, Mohammad; Awan, Mohammad Naeem

2007-09-15

Nine months field survey was conducted from July 2004 to August 2005 to take the data on the distribution and population status of Himalayan ibex (Capra ibex sibirica) in the upper Neelum valley of Azad Kashmir. Survey was carried out using direct (senses) as well as indirect (sampling) methods. 122 animals of different categories were recorded in the study area. Total average population was composed of 31.79% male, 32.79% female, 25.41% young and 9.84% yearling animals. Various threats to the population of ibex in the area were also studied.

Telecommunication service markets through the year 2000 in relation to millimeter wave satellite systems

NASA Technical Reports Server (NTRS)

Stevenson, S. M.

1979-01-01

NASA is currently conducting a series of millimeter wave satellite system market studies to develop 30/20 GHz satellite system concepts that have commercial potential. Four contractual efforts were undertaken: two parallel and independent system studies and two parallel and independent market studies. The marketing efforts are focused on forecasting the total domestic demand for long haul telecommunications services for the 1980-2000 period. Work completed to date and reported in this paper include projections of: geographical distribution of traffic; traffic volume as a function of urban area size; and user identification and forecasted demand.

Arc Jet Flow Properties Determined from Laser-Induced Fluorescence of Atomic Nitrogen

NASA Technical Reports Server (NTRS)

Fletcher, Douglas; Wercinski, Paul F. (Technical Monitor)

1998-01-01

An laser-spectroscopic investigation of the thermocheMical state of arcjet flows is currently being conducted in the Aerodynamic Heating Facility (AHF) Circlet at NASA Ames Research Center. Downstream of the nozzle exit, but upstream of the test article, Laser-Induced Fluorescence (LIF) of atomic nitrogen is used to assess the nonequilibriuM distribution of flow enthalpy in the free stream. The two-photon LIF technique provides simultaneous measurements of free stream velocity, translational temperature, and nitrogen number density on the flow centerline. Along with information from facility instrumentation, these measurements allow a determination of the free stream total enthalpy, and its apportionment in to thermal, kinetic, and chemical mode contributions. Experimental results are presented and discussed for two different niti-ogen/argon test gas flow runs during which the current is varied while the pressure remains constant .

Separate Cl^- Conductances Activated by cAMP and Ca2+ in Cl^--Secreting Epithelial Cells

NASA Astrophysics Data System (ADS)

Cliff, William H.; Frizzell, Raymond A.

1990-07-01

We studied the cAMP- and Ca2+-activated secretory Cl^- conductances in the Cl^--secreting colonic epithelial cell line T84 using the whole-cell patch-clamp technique. Cl^- and K^+ currents were measured under voltage clamp. Forskolin or cAMP increased Cl^- current 2-15 times with no change in K^+ current. The current-voltage relation for cAMP-activated Cl^- current was linear from -100 to +100 mV and showed no time-dependent changes in current during voltage pulses. Ca2+ ionophores or increased pipette Ca2+ increased both Cl^- and K^+ currents 2-30 times. The Ca2+-activated Cl^- current was outwardly rectified, activated during depolarizing voltage pulses, and inactivated during hyperpolarizing voltage pulses. Addition of ionophore after forskolin further increased Cl^- conductance 1.5-5 times, and the current took on the time-dependent characteristics of that stimulated by Ca2+. Thus, cAMP and Ca2+ activate Cl^- conductances with different properties, implying that these second messengers activate different Cl^- channels or that they induce different conductive and kinetic states in the same Cl^- channel.

COMPARISON OF METHODS FOR ESTIMATING CONTEMPORARY COSTS: AN APPLICATION TO LIVER TRANSPLANTATION IN THE UNITED KINGDOM.

PubMed

Singh, Jeshika; Longworth, Louise

2017-01-01

Our study addresses the important issue of estimating treatment costs from historical data. It is a problem frequently faced by health technology assessment analysts. We compared four approaches used to estimate current costs when good quality contemporary data are not available using liver transplantation as an example. First, the total cost estimates extracted for patients from a cohort study, conducted in the 1990s, were inflated using a published inflation multiplier. Second, resource use estimates from the cohort study were extracted for hepatitis C patients and updated using current unit costs. Third, expert elicitation was carried out to identify changes in clinical practice over time and quantify current resource use. Fourth, routine data on resource use were obtained from National Health Service Blood and Transplant (NHSBT). The first two methods did not account for changes in clinical practice. Also the first was not specific to hepatitis patients. The use of experts confirmed significant changes in clinical practice. However, the quantification of resource use using experts is challenging as clinical specialists may not have a complete overview of clinical pathway. The NHSBT data are the most accurate reflection of transplantation and posttransplantation phase; however, data were not available for the whole pathway of care. The best estimate of total cost, combining NHSBT data and expert elicitation, is £121,211. Observational data from routine care are potentially the most reliable reflection of current resource use. Efforts should be made to make such data readily available and accessible to researchers. Expert elicitation provided reasonable estimates.

75 FR 49930 - Stakeholder Meeting Regarding Re-Evaluation of Currently Approved Total Coliform Analytical Methods

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-16

... Currently Approved Total Coliform Analytical Methods AGENCY: Environmental Protection Agency (EPA). ACTION... of currently approved Total Coliform Rule (TCR) analytical methods. At these meetings, stakeholders will be given an opportunity to discuss potential elements of a method re-evaluation study, such as...

Tranexamic acid versus aminocaproic acid for blood management after total knee and total hip arthroplasty: A systematic review and meta-analysis.

PubMed

Liu, Qiuliang; Geng, Peishuo; Shi, Longyan; Wang, Qi; Wang, Pengliang

2018-06-01

To compare the efficacy and safety of tranexamic acid and aminocaproic acid for reducing blood loss and transfusion requirements after total knee and total hip arthroplasty. We conduct electronic searches of Medline (1966-2017.11), PubMed (1966-2017.11), Embase (1980-2017.11), ScienceDirect (1985-2017.11) and the Cochrane Library (1900-2017.11). The primary outcomes, including total blood loss, hemoglobin decline and transfusion requirements. Secondary outcomes include length of hospital stay and postoperative complications such as the incidence of deep vein thrombosis and pulmonary embolism. Each outcome is combined and calculated using the statistical software STATA 12.0. Fixed/random effect model is adopted based on the heterogeneity tested by I 2 statistic. A total of 1714 patients are analyzed across three randomized controlled trials (RCTs) and one non-RCT. The present meta-analysis reveals that TXA is associated with a significantly reduction of total blood loss and postoperative hemoglobin drop compared with EACA. No significant differences are identified in terms of transfusion rates, length of hospital stay, and the incidence of postoperative complications. Although total blood loss and postoperative hemoglobin drop are significant greater in EACA groups, there is no significant difference between TXA and EACA groups in terms of transfusion rates. Based on the current evidence available, higher quality RCTs are still required for further research. Copyright © 2018 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Nanoscale Electronic Conditioning for Improvement of Nanowire Light-Emitting-Diode Efficiency.

PubMed

May, Brelon J; Belz, Matthew R; Ahamed, Arshad; Sarwar, A T M G; Selcu, Camelia M; Myers, Roberto C

2018-04-24

Commercial III-Nitride LEDs and lasers spanning visible and ultraviolet wavelengths are based on epitaxial films. Alternatively, nanowire-based III-Nitride optoelectronics offer the advantage of strain compliance and high crystalline quality growth on a variety of inexpensive substrates. However, nanowire LEDs exhibit an inherent property distribution, resulting in uneven current spreading through macroscopic devices that consist of millions of individual nanowire diodes connected in parallel. Despite being electrically connected, only a small fraction of nanowires, sometimes <1%, contribute to the electroluminescence (EL). Here, we show that a population of electrical shorts exists in the devices, consisting of a subset of low-resistance nanowires that pass a large portion of the total current in the ensemble devices. Burn-in electronic conditioning is performed by applying a short-term overload voltage; the nanoshorts experience very high current density, sufficient to render them open circuits, thereby forcing a new current path through more nanowire LEDs in an ensemble device. Current-voltage measurements of individual nanowires are acquired using conductive atomic force microscopy to observe the removal of nanoshorts using burn-in. In macroscopic devices, this results in a 33× increase in peak EL and reduced leakage current. Burn-in conditioning of nanowire ensembles therefore provides a straightforward method to mitigate nonuniformities inherent to nanowire devices.

Novel Quantification of Sediment Concentration in Turbidity Currents Through in-situ Measurements of Conductivity and Temperature

NASA Astrophysics Data System (ADS)

Xu, J.; Wang, Z.; Gwiazda, R.; Paull, C. K.; Talling, P.; Parsons, D. R.; Maier, K. L.; Simmons, S.; Cartigny, M.

2017-12-01

During a large turbidity current event observed by seven moorings placed along Monterey Canyon, offshore central California, in the axial channel between 300 and 1900 meters water depth, a conductivity/temperature sensor placed 11 meters above canyon floor on the mooring at 1500 meters water depth recorded a rapid decrease of conductivity and increase of temperature during the passage of a large turbidity current. The conductivity decline is unlikely caused by fresh water input owing to lack of precipitation in the region prior to the event. We investigated the mechanisms of turbidity currents' high sediment concentration reducing the measured conductivity. By conducting a series of laboratory experiments with a range of different concentrations, grain size, and water temperature combinations, we quantified a relationship between reduced conductivity and the elevated sediment concentration. This relationship can be used for estimating the very high sediment concentrations in a turbidity current with a condition of assuming constant salinity of the ambient seawater. The empirical relationship was then applied to the in-situ time-series of temperature and conductivity measured during this turbidity current. The highest sediment concentration, in the head of the flow, reached nearly 400 g/L (volume concentration 17%). Such a high value, which has yet been reported in literature for an oceanic turbidity current, will have significant implications for the dynamics and deposits of such flows.

Interventions addressing risk factors of ischaemic heart disease in sub-Saharan Africa: a systematic review

PubMed Central

Ebireri, Jennifer; Aderemi, Adewale V; Omoregbe, Nicholas; Adeloye, Davies

2016-01-01

Background Ischaemic heart disease (IHD) is currently ranked eighth among the leading causes of deaths in sub-Saharan Africa (sSA). Yet, effective population-wide preventive measures targeting risks in the region are still largely unavailable. We aimed to review population-wide and individual-level interventions addressing risk factors of IHD among adults in sSA. Methods A systematic search of MEDLINE, EMBASE, Global Health and AJOL was conducted to identify studies focusing on population-wide and individual-level interventions targeting risks of IHD among adults in sSA. We conducted a detailed synthesis of basic findings of selected studies. Results A total of 2311 studies were identified, with only 9 studies meeting our selection criteria. 3 broad interventions were identified: dietary modifications, physical activity and community-based health promotion measures on tobacco and alcohol cessation. 3 studies reported significant reduction in blood pressure (BP), and another study reported statistically significant reduction in mean total cholesterol. Other outcome measures observed ranged from mild to no reduction in BP, blood glucose, body mass index and total cholesterol, respectively. Conclusions We cannot specify with all certainty contextually feasible interventions that can be effective in modifying IHD risk factors in population groups across sSA. We recommend more research on IHD, particularly on the understanding of the burden, geared towards developing and/or strengthening preventive and treatment interventions for the disease in sSA. PMID:27381212

GLM Post Launch Testing and Airborne Science Field Campaign

NASA Astrophysics Data System (ADS)

Goodman, S. J.; Padula, F.; Koshak, W. J.; Blakeslee, R. J.

2017-12-01

The Geostationary Operational Environmental Satellite (GOES-R) series provides the continuity for the existing GOES system currently operating over the Western Hemisphere. The Geostationary Lightning Mapper (GLM) is a wholly new instrument that provides a capability for total lightning detection (cloud and cloud-to-ground flashes). The first satellite in the GOES-R series, now GOES-16, was launched in November 2016 followed by in-orbit post launch testing for approximately 12 months before being placed into operations replacing the GOES-E satellite in December. The GLM will map total lightning continuously throughout day and night with near-uniform spatial resolution of 8 km with a product latency of less than 20 sec over the Americas and adjacent oceanic regions. The total lightning is very useful for identifying hazardous and severe thunderstorms, monitoring storm intensification and tracking evolution. Used in tandem with radar, satellite imagery, and surface observations, total lightning data has great potential to increase lead time for severe storm warnings, improve aviation safety and efficiency, and increase public safety. In this paper we present initial results from the post-launch in-orbit performance testing, airborne science field campaign conducted March-May, 2017 and assessments of the GLM instrument and science products.

Quasi-ballistic Electronic Thermal Conduction in Metal Inverse Opals.

PubMed

Barako, Michael T; Sood, Aditya; Zhang, Chi; Wang, Junjie; Kodama, Takashi; Asheghi, Mehdi; Zheng, Xiaolin; Braun, Paul V; Goodson, Kenneth E

2016-04-13

Porous metals are used in interfacial transport applications that leverage the combination of electrical and/or thermal conductivity and the large available surface area. As nanomaterials push toward smaller pore sizes to increase the total surface area and reduce diffusion length scales, electron conduction within the metal scaffold becomes suppressed due to increased surface scattering. Here we observe the transition from diffusive to quasi-ballistic thermal conduction using metal inverse opals (IOs), which are metal films that contain a periodic arrangement of interconnected spherical pores. As the material dimensions are reduced from ∼230 nm to ∼23 nm, the thermal conductivity of copper IOs is reduced by more than 57% due to the increase in surface scattering. In contrast, nickel IOs exhibit diffusive-like conduction and have a constant thermal conductivity over this size regime. The quasi-ballistic nature of electron transport at these length scales is modeled considering the inverse opal geometry, surface scattering, and grain boundaries. Understanding the characteristics of electron conduction at the nanoscale is essential to minimizing the total resistance of porous metals for interfacial transport applications, such as the total electrical resistance of battery electrodes and the total thermal resistance of microscale heat exchangers.

Quantifying plant age and available water effects on soybean leaf conductance

USDA-ARS?s Scientific Manuscript database

In this study, we present data characterizing the effects of soil moisture levels on total leaf conductance for two distinct determinate soybean (Glycine max (L.) Merr.) genotypes and subsequently use these data to formulate and validate a model that characterizes total leaf conductance. Conductanc...

Continuous water-quality monitoring and regression analysis to estimate constituent concentrations and loads in the Red River of the North, Fargo, North Dakota, 2003-05

USGS Publications Warehouse

Ryberg, Karen R.

2006-01-01

This report presents the results of a study by the U.S. Geological Survey, done in cooperation with the Bureau of Reclamation, U.S. Department of the Interior, to estimate water-quality constituent concentrations in the Red River of the North at Fargo, North Dakota. Regression analysis of water-quality data collected in 2003-05 was used to estimate concentrations and loads for alkalinity, dissolved solids, sulfate, chloride, total nitrite plus nitrate, total nitrogen, total phosphorus, and suspended sediment. The explanatory variables examined for regression relation were continuously monitored physical properties of water-streamflow, specific conductance, pH, water temperature, turbidity, and dissolved oxygen. For the conditions observed in 2003-05, streamflow was a significant explanatory variable for all estimated constituents except dissolved solids. pH, water temperature, and dissolved oxygen were not statistically significant explanatory variables for any of the constituents in this study. Specific conductance was a significant explanatory variable for alkalinity, dissolved solids, sulfate, and chloride. Turbidity was a significant explanatory variable for total phosphorus and suspended sediment. For the nutrients, total nitrite plus nitrate, total nitrogen, and total phosphorus, cosine and sine functions of time also were used to explain the seasonality in constituent concentrations. The regression equations were evaluated using common measures of variability, including R2, or the proportion of variability in the estimated constituent explained by the regression equation. R2 values ranged from 0.703 for total nitrogen concentration to 0.990 for dissolved-solids concentration. The regression equations also were evaluated by calculating the median relative percentage difference (RPD) between measured constituent concentration and the constituent concentration estimated by the regression equations. Median RPDs ranged from 1.1 for dissolved solids to 35.2 for total nitrite plus nitrate. Regression equations also were used to estimate daily constituent loads. Load estimates can be used by water-quality managers for comparison of current water-quality conditions to water-quality standards expressed as total maximum daily loads (TMDLs). TMDLs are a measure of the maximum amount of chemical constituents that a water body can receive and still meet established water-quality standards. The peak loads generally occurred in June and July when streamflow also peaked.

Electrical Properties of Bismuth/Lithium-Cosubstituted Strontium Titanate Ceramics

NASA Astrophysics Data System (ADS)

Alkathy, Mahmoud. S.; James Raju, K. C.

2018-03-01

Sr(1-x)(Bi,Li) x TiO3 compound was prepared via a solid-state reaction route with microwave heating of the starting materials. X-ray diffraction analysis revealed pure perovskite phase without formation of any secondary phases. The electrical conductivity was studied as a function of temperature and frequency. The experimental results indicate that the alternating-current (AC) conductivity increased with frequency, following the Jonscher power law. To interpret the possible mechanism for electrical conduction, the correlated barrier hopping model was applied. The effect of temperature and the Bi/Li concentration on the electrical resistivity was studied. The results showed that the electrical resistivity decreased with increasing temperature, which could be due to increased thermal energy of electrons. Also, the electrical resistivity decreased with increase in the amount of Bi and Li, which could be due to increased concentration of structural defects, which could increase the number of either electrons or holes available for conduction. A single semicircular arc corresponding to a single relaxation process was observed for all the investigated ceramics, suggesting a grain contribution to the total resistance in these materials. Arrhenius plots were used to obtain the activation energy for the samples.

Electrical Properties of Bismuth/Lithium-Cosubstituted Strontium Titanate Ceramics

NASA Astrophysics Data System (ADS)

Alkathy, Mahmoud. S.; James Raju, K. C.

2018-07-01

Sr(1- x)(Bi,Li) x TiO3 compound was prepared via a solid-state reaction route with microwave heating of the starting materials. X-ray diffraction analysis revealed pure perovskite phase without formation of any secondary phases. The electrical conductivity was studied as a function of temperature and frequency. The experimental results indicate that the alternating-current (AC) conductivity increased with frequency, following the Jonscher power law. To interpret the possible mechanism for electrical conduction, the correlated barrier hopping model was applied. The effect of temperature and the Bi/Li concentration on the electrical resistivity was studied. The results showed that the electrical resistivity decreased with increasing temperature, which could be due to increased thermal energy of electrons. Also, the electrical resistivity decreased with increase in the amount of Bi and Li, which could be due to increased concentration of structural defects, which could increase the number of either electrons or holes available for conduction. A single semicircular arc corresponding to a single relaxation process was observed for all the investigated ceramics, suggesting a grain contribution to the total resistance in these materials. Arrhenius plots were used to obtain the activation energy for the samples.

Associating ground magnetometer observations with current or voltage generators

NASA Astrophysics Data System (ADS)

Hartinger, M. D.; Xu, Z.; Clauer, C. R.; Yu, Y.; Weimer, D. R.; Kim, H.; Pilipenko, V.; Welling, D. T.; Behlke, R.; Willer, A. N.

2017-07-01

A circuit analogy for magnetosphere-ionosphere current systems has two extremes for drivers of ionospheric currents: ionospheric electric fields/voltages constant while current/conductivity vary—the "voltage generator"—and current constant while electric field/conductivity vary—the "current generator." Statistical studies of ground magnetometer observations associated with dayside Transient High Latitude Current Systems (THLCS) driven by similar mechanisms find contradictory results using this paradigm: some studies associate THLCS with voltage generators, others with current generators. We argue that most of this contradiction arises from two assumptions used to interpret ground magnetometer observations: (1) measurements made at fixed position relative to the THLCS field-aligned current and (2) negligible auroral precipitation contributions to ionospheric conductivity. We use observations and simulations to illustrate how these two assumptions substantially alter expectations for magnetic perturbations associated with either a current or a voltage generator. Our results demonstrate that before interpreting ground magnetometer observations of THLCS in the context of current/voltage generators, the location of a ground magnetometer station relative to the THLCS field-aligned current and the location of any auroral zone conductivity enhancements need to be taken into account.

Short-term outcomes of extracorporeal shock wave therapy for the treatment of chronic non-calcific tendinopathy of the supraspinatus: a double-blind, randomized, placebo-controlled trial

PubMed Central

2012-01-01

Background There is evidence supporting the use of extracorporeal shock wave therapy (ESWT) in calcific tendinopathy of the rotator cuff, but the best current evidence does not support its use in non-calcifying tendinopathy. We conducted a randomized placebo-controlled trial to investigate the efficacy and safety of low energy ESWT for non-calcifying tendinopathy of the rotator cuff. Methods 20 patients with non-calcifying supraspinatus tendinopathy (NCST) were randomized to an active or a sham treatment group. Physical, blood, roentgenographic, and MRI examinations of the shoulder were conducted to verify that patients met the inclusion and exclusion criteria. These examinations were repeated six and twelve weeks after treatments. Effectiveness was determined by comparison of the mean improvement in the Constant and Murley score (CMS) between the treatment and the placebo groups at three months. Safety was assessed by analyzing the number and severity of adverse events. Results All the patients completed the investigation protocol. At the final follow-up, significant improvement in the total CMS score and most of the CMS subscales was observed in the ESWT group when compared to the baseline values. Significantly higher total CMS, and significantly higher scores for CMS pain and ROM were observed in the ESWT group when compared to the placebo. No serious adverse events were noted after ESWT. Conclusions Patients suffering from NCST may benefit from low energy ESWT, at least in short-term. The application protocol of ESWT is likely to play a key-role in a successful treatment. Future investigations should be undertaken on the long-term effects of this technique for the treatment of NCST. Trial registration Current Controlled Trials ISRCTN41236511 PMID:22672772

Tribology and total hip joint replacement: current concepts in mechanical simulation.

PubMed

Affatato, S; Spinelli, M; Zavalloni, M; Mazzega-Fabbro, C; Viceconti, M

2008-12-01

Interest in the rheology and effects of interacting surfaces is as ancient as man. This subject can be represented by a recently coined word: tribology. This term is derived from the Greek word "tribos" and means the "science of rubbing". Friction, lubrication, and wear mechanism in the common English language means the precise field of interest of tribology. Wear of total hip prosthesis is a significant clinical problem that involves, nowadays, a too high a number of patients. In order to acquire further knowledge on the tribological phenomena that involve hip prosthesis wear tests are conducted on employed materials to extend lifetime of orthopaedic implants. The most basic type of test device is the material wear machine, however, a more advanced one may more accurately reproduce some of the in vivo conditions. Typically, these apparatus are called simulators, and, while there is no absolute definition of a joint simulator, its description as a mechanical rig used to test a joint replacement, under conditions approximating those occurring in the human body, is acceptable. Simulator tests, moreover, can be used to conduct accelerated protocols that replicate/simulate particularly extreme conditions, thus establishing the limits of performance for the material. Simulators vary in their level of sophistication and the international literature reveals many interpretations of the design of machines used for joint replacement testing. This paper aims to review the current state of the art of the hip joint simulators worldwide. This is specified through a schematic overview by describing, in particular, constructive solutions adopted to reproduce in vivo conditions. An exhaustive commentary on the evolution and actually existing simulation standards is proposed by the authors. The need of a shared protocol among research laboratories all over the world could lead to a consensus conference.

Short-term outcomes of extracorporeal shock wave therapy for the treatment of chronic non-calcific tendinopathy of the supraspinatus: a double-blind, randomized, placebo-controlled trial.

PubMed

Galasso, Olimpio; Amelio, Ernesto; Riccelli, Daria Anna; Gasparini, Giorgio

2012-06-06

There is evidence supporting the use of extracorporeal shock wave therapy (ESWT) in calcific tendinopathy of the rotator cuff, but the best current evidence does not support its use in non-calcifying tendinopathy. We conducted a randomized placebo-controlled trial to investigate the efficacy and safety of low energy ESWT for non-calcifying tendinopathy of the rotator cuff. 20 patients with non-calcifying supraspinatus tendinopathy (NCST) were randomized to an active or a sham treatment group. Physical, blood, roentgenographic, and MRI examinations of the shoulder were conducted to verify that patients met the inclusion and exclusion criteria. These examinations were repeated six and twelve weeks after treatments. Effectiveness was determined by comparison of the mean improvement in the Constant and Murley score (CMS) between the treatment and the placebo groups at three months. Safety was assessed by analyzing the number and severity of adverse events. All the patients completed the investigation protocol. At the final follow-up, significant improvement in the total CMS score and most of the CMS subscales was observed in the ESWT group when compared to the baseline values. Significantly higher total CMS, and significantly higher scores for CMS pain and ROM were observed in the ESWT group when compared to the placebo. No serious adverse events were noted after ESWT. Patients suffering from NCST may benefit from low energy ESWT, at least in short-term. The application protocol of ESWT is likely to play a key-role in a successful treatment. Future investigations should be undertaken on the long-term effects of this technique for the treatment of NCST. Current Controlled Trials ISRCTN41236511.

Systems design and comparative analysis of large antenna concepts

NASA Technical Reports Server (NTRS)

Garrett, L. B.; Ferebee, M. J., Jr.

1983-01-01

Conceptual designs are evaluated and comparative analyses conducted for several large antenna spacecraft for Land Mobile Satellite System (LMSS) communications missions. Structural configurations include trusses, hoop and column and radial rib. The study was conducted using the Interactive Design and Evaluation of Advanced Spacecraft (IDEAS) system. The current capabilities, development status, and near-term plans for the IDEAS system are reviewed. Overall capabilities are highlighted. IDEAS is an integrated system of computer-aided design and analysis software used to rapidly evaluate system concepts and technology needs for future advanced spacecraft such as large antennas, platforms, and space stations. The system was developed at Langley to meet a need for rapid, cost-effective, labor-saving approaches to the design and analysis of numerous missions and total spacecraft system options under consideration. IDEAS consists of about 40 technical modules efficient executive, data-base and file management software, and interactive graphics display capabilities.

Occupational health and safety issues in Ontario sawmills and veneer/plywood plants: a pilot study.

PubMed

Verma, Dave K; Demers, Cecil; Shaw, Don; Verma, Paul; Kurtz, Lawrence; Finkelstein, Murray; des Tombe, Karen; Welton, Tom

2010-01-01

A pilot study was conducted within the Ontario sawmill and veneer/plywood manufacturing industry. Information was collected by postal questionnaire and observational walk-through surveys. Industrial hygiene walk-through surveys were conducted at 22 work sites, and measurements for wood dust, noise, and bioaerosol were taken. The aim of the study was to obtain data on the current status regarding health and safety characteristics and an estimate of wood dust, noise, and bioaerosol exposures. The occupational exposure to wood dust and noise are similar to what has been reported in this industry in Canada and elsewhere. Airborne wood dust concentration ranged between 0.001 mg/m³ and 4.87 mg/m³ as total dust and noise exposure ranged between 55 and 117 dB(A). The study indicates the need for a more comprehensive industry-wide study of wood dust, noise, and bioaersols.

Lightweight, High-Temperature Radiator for Space Propulsion

NASA Technical Reports Server (NTRS)

Hyers, R. W.; Tomboulian, B. N.; Crave, Paul D.; Rogers, J. R.

2012-01-01

For high-power nuclear-electric spacecraft, the radiator can account for 40% or more of the power system mass and a large fraction of the total vehicle mass. Improvements in the heat rejection per unit mass rely on lower-density and higher-thermal conductivity materials. Current radiators achieve near-ideal surface radiation through high-emissivity coatings, so improvements in heat rejection per unit area can be accomplished only by raising the temperature at which heat is rejected. We have been investigating materials that have the potential to deliver significant reductions in mass density and significant improvements in thermal conductivity, while expanding the feasible range of temperature for heat rejection up to 1000 K and higher. The presentation will discuss the experimental results and models of the heat transfer in matrix-free carbon fiber fins. Thermal testing of other carbon-based fin materials including carbon nanotube cloth and a carbon nanotube composite will also be presented.

Occupational Health and Safety Issues in Ontario Sawmills and Veneer/Plywood Plants: A Pilot Study

PubMed Central

Verma, Dave K.; Demers, Cecil; Shaw, Don; Verma, Paul; Kurtz, Lawrence; Finkelstein, Murray; des Tombe, Karen; Welton, Tom

2010-01-01

A pilot study was conducted within the Ontario sawmill and veneer/plywood manufacturing industry. Information was collected by postal questionnaire and observational walk-through surveys. Industrial hygiene walk-through surveys were conducted at 22 work sites, and measurements for wood dust, noise, and bioaerosol were taken. The aim of the study was to obtain data on the current status regarding health and safety characteristics and an estimate of wood dust, noise, and bioaerosol exposures. The occupational exposure to wood dust and noise are similar to what has been reported in this industry in Canada and elsewhere. Airborne wood dust concentration ranged between 0.001 mg/m3 and 4.87 mg/m3 as total dust and noise exposure ranged between 55 and 117 dB(A). The study indicates the need for a more comprehensive industry-wide study of wood dust, noise, and bioaersols. PMID:21253473

The Efficiency of Reproduction Health Education Given to Adolescents during the Postpartum Period.

PubMed

Topatan, Serap; Demirci, Nurdan

2015-10-01

Our research, partly experimental and partly prospective, was conducted for the purpose of evaluating the efficiency of reproductive health education given to adolescents during the postpartum period. The study comprised with 120 adolescents aged 15 to 19 (60 experimental group, 60 control group). Follow-up was conducted every 3 months for a total of 12 months, and the study concluded with 55 individuals from the experimental group and 46 individuals from the control group having participated fully, for the full 12 months. At the end of the research, it was found that the reproductive health knowledge of the experimental (103.10 ± 11.43) and control (99.15 ± 9.53) groups were similar before education. A statistically significant difference was also found between the total points for the scale determining the reproductive health of the experimental and control groups before and after education (P < .001). The socio-demographic variables affecting the total points for the scale determining the reproductive health-protective behavior of women were evaluated by multiple regression analysis; the most effective variables were found to be age and educational status. A statistically significant difference was also found between the total points for the family planning behavior scale of the experimental and control groups before and after education (P < .001). From this, it was understood that reproductive health education given during the postpartum and follow-up periods has a positive effect on adolescents' developing reproductive health behaviors and on creating knowledge and awareness related to family planning behavior. But there needs to be follow-up and supporting specific for adolescents in the current health system. Copyright © 2015 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Thermally Conductive Tape Based on Carbon Nanotube Arrays

NASA Technical Reports Server (NTRS)

Kashani, Ali

2011-01-01

To increase contact conductance between two mating surfaces, a conductive tape has been developed by growing dense arrays of carbon nanotubes (CNTs, graphite layers folded into cylinders) on both sides of a thermally conductive metallic foil. When the two mating surfaces are brought into contact with the conductive tape in between, the CNT arrays will adhere to the mating surface. The van der Waals force between the contacting tubes and the mating surface provides adhesion between the two mating surfaces. Even though the thermal contact conductance of a single tube-to-tube contact is small, the tremendous amount of CNTs on the surface leads to a very large overall contact conductance. Interface contact thermal resistance rises from the microroughness and the macroscopic non-planar quality of mating surfaces. When two surfaces come into contact with each other, the actual contact area may be much less than the total area of the surfaces. The real area of contact depends on the load, the surface roughness, and the elastic and inelastic properties of the surface. This issue is even more important at cryogenic temperatures, where materials become hard and brittle and vacuum is used, which prevents any gas conduction through the interstitial region. A typical approach to increase thermal contact conductance is to use thermally conducting epoxies or greases, which are not always compatible with vacuum conditions. In addition, the thermal conductivities of these compounds are often relatively low. The CNTs used in this approach can be metallic or semiconducting, depending on the folding angle and diameter. The electrical resistivity of multiwalled carbon nanotubes (MWCNTs) has been reported. MWCNTs can pass a current density and remain stable at high temperatures in air. The thermal conductivity of a MWCNT at room temperature is measured to be approximately 3,000 W/m-K, which is much larger than that of diamond. At room temperature, the thermal conductance of a 0.3 sq cm array of CNTs was measured to be as high as 10 W/K. The high thermal conductivity and the nanoscale size make CNTs ideal as thermal interface materials. The CNT-based thermal tape can be used for the thermal management of microelectronic packages and electronic systems. It also can be integrated with current device technology and packaging. The material would allow for an efficient method to manage excess heat generation without requiring any additional power. Lastly, the CNT tape can be used to enhance thermal contact conductance across two mating surfaces on some NASA missions.

Costs of occupational injury and illness across industries.

PubMed

Leigh, J Paul; Waehrer, Geetha; Miller, Ted R; Keenan, Craig

2004-06-01

This study has ranked industries using estimated total costs and costs per worker. This incidence study of nationwide data was carried out in 1993. The main outcome measure was total cost for medical care, lost productivity, and pain and suffering for the entire United States (US). The analysis was conducted using fatal and nonfatal injury and illness data recorded in large data sets from the US Bureau of Labor Statistics. Cost data were derived from workers' compensation records, estimates of lost wages, and jury awards. Current-value calculations were used to express all costs in 1993 in US dollars. The following industries were at the top of the list for average cost (cost per worker): taxicabs, bituminous coal and lignite mining, logging, crushed stone, oil field services, water transportation services, sand and gravel, and trucking. Industries high on the total-cost list were trucking, eating and drinking places, hospitals, grocery stores, nursing homes, motor vehicles, and department stores. Industries at the bottom of the cost-per-worker list included legal services, security brokers, mortgage bankers, security exchanges, and labor union offices. Detailed methodology was developed for ranking industries by total cost and cost per worker. Ranking by total costs provided information on total burden of hazards, and ranking by cost per worker provided information on risk. Industries that ranked high on both lists deserve increased research and regulatory attention.

Numerical and experimental study of the effect of the induced electric potential in Lorentz force velocimetry

NASA Astrophysics Data System (ADS)

Hernández, Daniel; Boeck, Thomas; Karcher, Christian; Wondrak, Thomas

2018-01-01

Lorentz force velocimetry (LFV) is a contactless velocity measurement technique for electrically conducting fluids. When a liquid metal or a molten glass flows through an externally applied magnetic field, eddy currents and a flow-braking force are generated inside the liquid. This force is proportional to the velocity or flow rate of the fluid and, due to Newton’s third law, a force of the same magnitude but in opposite direction acts on the source of the applied magnetic field which in our case are permanent magnets. According to Ohm’s law for moving conductors at low magnetic Reynolds numbers, an electric potential is induced which ensures charge conservation. In this paper, we analyze the contribution of the induced electric potential to the total Lorentz force by considering two different scenarios: conducting walls of finite thickness and aspect ratio variation of the cross-section of the flow. In both the cases, the force component generated by the electric potential is always in the opposite direction to the total Lorentz force. This force component is sensitive to the electric boundary conditions of the flow of which insulating and perfectly conducting walls are the two limiting cases. In the latter case, the overall electric resistance of the system is minimized, resulting in a considerable increase in the measured Lorentz force. Additionally, this force originating from the electric potential also decays when the aspect ratio of the cross-section of the flow is changed. Hence, the sensitivity of the measurement technique is enhanced by either increasing wall conductivity or optimizing the aspect ratio of the cross-section of the flow.

Field-Aligned Currents in Saturn's Nightside Magnetosphere: Subcorotation and Planetary Period Oscillation Components During Northern Spring

NASA Astrophysics Data System (ADS)

Bradley, T. J.; Cowley, S. W. H.; Provan, G.; Hunt, G. J.; Bunce, E. J.; Wharton, S. J.; Alexeev, I. I.; Belenkaya, E. S.; Kalegaev, V. V.; Dougherty, M. K.

2018-05-01

We newly analyze Cassini magnetic field data from the 2012/2013 Saturn northern spring interval of highly inclined orbits and compare them with similar data from late southern summer in 2008, thus providing unique information on the seasonality of the currents that couple momentum between Saturn's ionosphere and magnetosphere. Inferred meridional ionospheric currents in both cases consist of a steady component related to plasma subcorotation, together with the rotating current systems of the northern and southern planetary period oscillations (PPOs). Subcorotation currents during the two intervals show opposite north-south polar region asymmetries, with strong equatorward currents flowing in the summer hemispheres but only weak currents flowing to within a few degrees of the open-closed boundary (OCB) in the winter hemispheres, inferred due to weak polar ionospheric conductivities. Currents peak at 1 MA rad-1 in both hemispheres just equatorward of the open-closed boundary, associated with total downward polar currents 6 MA, then fall across the narrow auroral upward current region to small values at subauroral latitudes. PPO-related currents have a similar form in both summer and winter with principal upward and downward field-aligned currents peaking at 1.25 MA rad-1 being essentially collocated with the auroral upward current and approximately equal in strength. Though northern and southern PPO currents were approximately equal during both intervals, the currents in both hemispheres were dual modulated by both systems during 2012/2013, with approximately half the main current closing in the opposite ionosphere and half cross field in the magnetosphere, while only the northern hemisphere currents were similarly dual modulated in 2008.

Polio immunization policy in Mexico: economic assessment of current practice and future alternatives.

PubMed

Mascareñas, A; Salinas, J; Tasset-Tisseau, A; Mascareñas, C; Khan, M M

2005-06-01

The World Health Organization recommends that all children aged less than 5 years should be vaccinated against polio through intensive immunization programmes as well as routine immunization. A national immunization week (NIW) was held in February 2002 in the Monterrey district of Mexico. A prospective micro-costing study was conducted to measure the total cost to the state of the NIW, the cost profile, and the ratio of cost per immunization contact to cost per dose of oral polio vaccine (OPV), and to compare OPV and inactive polio vaccine (IPV) in economic terms. Two scenarios were used as the basis for calculation. The cost of volunteers was excluded from the "lower-cost scenario" and included in the "upper-cost scenario". The total cost of the NIW was USD 100,454 for the lower-cost scenario and USD 156,614 for the upper-cost scenario. The major part of the costs was personnel costs (67.30 and 77.53% of the total costs in the lower- and upper-cost scenario, respectively). The ratio of cost per immunization contact to cost per dose of OPV was 6.45 for the lower-cost scenario and 10.05 for the upper-cost scenario. Changing from the current OPV-based intensive and routine schedule to a sequential IPV-OPV routine schedule would save USD 14.52 per vaccinated child, and changing to a full IPV routine schedule would save USD 9.41 per vaccinated child.

A Qualitative Evaluation of Engagement and Attrition in a Nurse Home Visiting Program: From the Participant and Provider Perspective.

PubMed

Beasley, Lana O; Ridings, Leigh E; Smith, Tyler J; Shields, Jennifer D; Silovsky, Jane F; Beasley, William; Bard, David

2018-05-01

Beginning parenting programs in the prenatal and early postnatal periods have a large potential for impact on later child and maternal outcomes. Home-based parenting programs, such as the Nurse Family Partnership (NFP), have been established to help address this need. Program reach and impact is dependent on successful engagement of expecting mothers with significant risks; however, NFP attrition rates remain high. The current study qualitatively examined engagement and attrition from the perspectives of NFP nurses and mothers in order to identify mechanisms that enhance service engagement. Semi-structured interviews were conducted in focus groups composed of either engaged (27 total mothers) or unengaged (15 total mothers) mothers from the NFP program. NFP nurses (25 total nurses) were recruited for individual semi-structured interviews. Results suggest that understanding engagement in the NFP program requires addressing both initial and sustained engagement. Themes associated with enhanced initial engagement include nurse characteristics (e.g., flexible, supportive, caring) and establishment of a solid nurse-family relationship founded on these characteristics. Factors impacting sustained engagement include nurse characteristics, provision of educational materials on child development, individualized services for families, and available family support. Identified barriers to completing services include competing demands and lack of support. Findings of this study have direct relevance for workforce planning, including hiring and training through integrating results regarding effective nurse characteristics. Additional program supports to enhance parent engagement may be implemented across home-based parenting programs in light of the current study's findings.

Inclusion of children with developmental disabilities in Arab countries: A review of the research literature from 1990 to 2014.

PubMed

Alkhateeb, Jamal M; Hadidi, Muna S; Alkhateeb, Amal J

2016-01-01

In this study, a literature review was conducted to analyze studies published from 1990 to 2014 in English-written literature on inclusion of children with developmental disabilities in Arab countries. This study sought to review and analyze research conducted on Inclusive Education (IE) in Arab countries. The following electronic databases were used in searching the relevant literature: ScienceDirect, SpringerLink, PsychINFO, EBSCOhost Databases, ProQuest Dissertations and Theses Database, ERIC, and Google Scholar. After the publications to be included in this study were retrieved, each study was reviewed and analyzed. Each study was examined for details such as authors, title of research, publication year, country, purpose, methods, and key findings. The results showed that a total of 42 empirical studies related to inclusion of children with developmental disabilities in Arab countries have been published. More than two-thirds of these studies came from United Arab Emirates (UAE), Jordan, and Saudi Arabia. The majority of the studies were published in the last 6 years. The main parameters in these studies were: attitudes toward inclusion, barriers to inclusion, and evaluating inclusion. The results of the current study revealed that relatively little IE research has been conducted in Arab countries. More research is warranted to test the generalizability of the results of the current study. Further research is also needed to analyze IE practices and demonstrate strategies for the effective implementation of IE in these countries. Copyright © 2015 Elsevier Ltd. All rights reserved.

Validation of a Chichewa version of the self-reporting questionnaire (SRQ) as a brief screening measure for maternal depressive disorder in Malawi, Africa.

PubMed

Stewart, Robert C; Kauye, Felix; Umar, Eric; Vokhiwa, Maclean; Bunn, James; Fitzgerald, Margaret; Tomenson, Barbara; Rahman, Atif; Creed, Francis

2009-01-01

Depressive disorder affecting women during the perinatal period is common in low-income countries. The detection and study of maternal depression in a resource-poor setting requires a brief screening tool that is both accurate and practical to administer. A Chichewa version of the Self Reporting Questionnaire (SRQ) was developed through a rigorous process of forward and back translation, focus-group discussion and piloting. Criterion validation was conducted as part of a larger study in a sample of women who had brought their infants to a child health clinic in rural Malawi, using DSM-IV major and minor depressive episode as the gold standard diagnoses. The criterion validation was conducted on 114 subjects who did not differ on health and sociodemographic characteristics from the total study sample (n=501). Test characteristics for each possible SRQ cut-off were calculated and Receiver Operator Characteristic (ROC) curves derived. Area under the ROC curve (AUROC) for detection of current major depressive disorder was 0.856 (95% CI 0.813 to 0.900), and for current major or minor depressive disorder was 0.826 (95% CI 0.783 to 0.869). Internal consistency of the SRQ was high (Cronbach's alpha 0.85). Inter-rater reliability testing was not conducted. This Chichewa version of the SRQ shows utility as a brief screening measure for detection of probable maternal depression in rural Malawi.

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

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

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

2016-08-15

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

10 CFR Appendix D to Part 30 - Criteria Relating to Use of Financial Tests and Self-Guarantee for Providing Reasonable Assurance...

Code of Federal Regulations, 2012 CFR

2012-01-01

... will be available for decommissioning costs and on a demonstration that the company passes the... total current decommissioning cost estimate (or the current amount required if certification is used... percent of total assets or at least 10 times the total current decommissioning cost estimate (or the...

Caffeine intake and its sources: A review of national representative studies.

PubMed

Verster, Joris C; Koenig, Juergen

2018-05-24

Aim of this review is to summarize current daily caffeine intake of children, adolescents, and adults, and trends in caffeine intake over the past decade. A literature search was conducted (1997-2015) which yielded 18 reports on nationally representative studies, describing caffeine consumption of over 275,000 children, adolescents and adults. The data revealed that mean total daily caffeine intake in children, adolescents, and adults is below caffeine intake recommendations such as those stated by Health Canada (2.5 mg/kg bw/day for children and adolescents, and 400 mg/day for adults) and the European Food Safety Authority, EFSA (3 mg/kg bw/day for children and adolescents, and 400 mg/day for adults). Total daily caffeine intake has remained stable in the last 10-15 years, and coffee, tea and soft drinks are the most important caffeine sources. Across all age groups, energy drinks contribute little to total caffeine intake. The highest potential for reducing daily caffeine intake is by limiting coffee consumption, and in some countries and age groups, by reducing tea and soft drink consumption.

Sustainability of Welding Process through Bobbin Friction Stir Welding

NASA Astrophysics Data System (ADS)

Sued, M. K.; Samsuri, S. S. M.; Kassim, M. K. A. M.; Nasir, S. N. N. M.

2018-03-01

Welding process is in high demand, which required a competitive technology to be adopted. This is important for sustaining the needs of the joining industries without ignoring the impact of the process to the environment. Friction stir welding (FSW) is stated to be benefitting the environment through low energy consumption, which cannot be achieved through traditional arc welding. However, this is not well documented, especially for bobbin friction stir welding (BFSW). Therefore, an investigation is conducted by measuring current consumption of the machine during the BFSW process. From the measurement, different phases of BFSW welding process and its electrical demand are presented. It is found that in general total energy in BFSW is about 130kW inclusive of all identified process phases. The phase that utilise for joint formation is in weld phase that used the highest total energy of 120kWs. The recorded total energy is still far below the traditional welding technology and the conventional friction stir welding (CFSW) energy demand. This indicates that BFSW technology with its vast benefit able to sustain the joining technology in near future.

Physicochemical parameters and microbiological status of honey produced in an urban environment in Serbia.

PubMed

Matović, Kazimir; Ćirić, Jelena; Kaljević, Vesna; Nedić, Nebojša; Jevtić, Goran; Vasković, Nikola; Baltić, Milan Ž

2018-05-01

Honey is a natural substance produced by honey bees (the genus Apis) enjoyed by people due to its unique nutritional and medicinal properties. The aim of this study was to determine the physicochemical parameters (moisture, ash, water-insoluble content, reducing sugars, sucrose, free acidity, diastase activity, hydroxymethylfurfural, and electrical conductivity) and microbiological status (total number of aerobic mesophilic bacteria, total number of sulfite-reducing clostridia, the presence of Salmonella spp., total numbers of fungi and yeasts and the presence of Clostridium botulinum) in honey (honeydew, blossom, sunflower, acacia, and linden) produced in an urban environment in Serbia. We analyzed 19 apiary samples of honey, collected during the 2011 harvesting season, by using recommendation methods. Physicochemical parameters of the examined honey produced in the urban environment indicated the honeys were of acceptable quality. Bacillus spp. were detected in four honeys, yeasts were detected in three honeys, and Clostridium botulinum type E was detected in one honey using PCR. The current study also showed the presence of diverse honey varieties in Serbia.

Portable Intravenous Fluid Production Device for Ground Use

NASA Technical Reports Server (NTRS)

Scarpa, Philip J.; Scheuer, Wolfgang K.

2012-01-01

There are several medical conditions that require intravenous (IV) fluids. Limitations of mass, volume, storage space, shelf-life, transportation, and local resources can restrict the availability of such important fluids. These limitations are expected in long-duration space exploration missions and in remote or austere environments on Earth. Current IV fluid production requires large factory-based processes. Easy, portable, on-site production of IV fluids can eliminate these limitations. Based on experience gained in developing a device for spaceflight, a ground-use device was developed. This design uses regular drinking water that is pumped through two filters to produce, in minutes, sterile, ultrapure water that meets the stringent quality standards of the United States Pharmacopeia for Water for Injection (Total Bacteria, Conductivity, Endotoxins, Total Organic Carbon). The device weighs 2.2 lb (1 kg) and is 10 in. long, 5 in. wide, and 3 in. high (.25, 13, and 7.5 cm, respectively) in its storage configuration. This handheld device produces one liter of medical-grade water in 21 minutes. Total production capacity for this innovation is expected to be in the hundreds of liters.

Mental health interventions for children exposed to disasters and terrorism.

PubMed

Pfefferbaum, Betty; Newman, Elana; Nelson, Summer D

2014-02-01

The purpose of this review is to describe interventions used with children who are exposed to disasters and terrorism and to present information about the potential benefits of these interventions. A literature search conducted in January 2013 using relevant databases and literature known to the authors that was not generated by the search yielded a total of 85 studies appropriate for review. Intervention approaches used with children exposed to disasters and terrorism included preparedness interventions, psychological first aid, psychological debriefing, psychoeducation, cognitive behavioral techniques, exposure and narrative techniques, eye movement desensitization and reprocessing, and traumatic grief interventions. The investigation of these interventions is complex, and studies varied in methodological rigor (e.g., sample size, the use of control groups, outcomes measured). Given the limitations in the currently available empirical information, this review integrates the literature, draws tentative conclusions about the current state of knowledge, and suggests future directions for study.

Adoption of Evidence-Based Practices Among Substance Abuse Treatment Providers*

PubMed Central

Haug, Nancy A.; Shopshire, Michael; Tajima, Barbara; Gruber, Valerie; Guydish, Joseph

2009-01-01

This research was conducted at a Substance Abuse Forum designed to address local community needs by focusing on Evidence-Based Practices (EBPs) in addiction treatment. The purpose of the study was to assess substance abuse treatment professionals’ readiness to adopt EBPs, experience with EBPs, and attitudes toward EBPs, as well as agency support for EBPs. A total of 119 addiction treatment providers completed pre-test measures, and 82% completed a post-test. Eighty-three percent of participants reported using some EBPs in the past year, and 75% reported currently using EBPs. Participants who were currently licensed or certified in addictions had less negative attitudes toward EBPs than those without credentials. While respondents reported agency support for EBPs, most expressed interest in further training. This study underscores the movement toward EBPs in addiction treatment and the need for effective dissemination and training in this area. PMID:18724657

Electronic Nicotine Delivery Systems (ENDS): What Nurses Need to Know.

PubMed

Essenmacher, Carol; Naegle, Madeline; Baird, Carolyn; Vest, Bridgette; Spielmann, Rene; Smith-East, Marie; Powers, Leigh

Efforts to decrease adverse effects of tobacco use are affected by emergence of new nicotine delivery products. Advertising, product promotion, and social media promote use of these products, yet a lack of evidence regarding safety leaves nurses unprepared to counsel patients. To critically evaluate current research, reviews of literature, expert opinion, and stakeholder policy proposals on use and safety of electronic nicotine delivery systems (ENDS). A targeted examination of literature generated by key stakeholders and subject matter experts was conducted using key words, modified by risk factors, and limited to the past 8 years. Current knowledge gaps in research literature and practice implications of the literature are discussed. The safety of ENDS is questionable and unclear. There are clear health risks of nicotine exposure to developing brains. Potential health risks of ENDS secondhand emissions exposure exist. Using ENDS to facilitate total tobacco cessation is not proven.

Thermal investigation of an electrical high-current arc with porous gas-cooled anode

NASA Technical Reports Server (NTRS)

Eckert, E. R. G.; Schoeck, P. A.; Winter, E. R. F.

1984-01-01

The following guantities were measured on a high-intensity electric arc with tungsten cathode and transpiration-cooled graphite anode burning in argon: electric current and voltage, cooling gas flow rate (argon), surface temperature of the anode and of the anode holder, and temperature profile in three cross-sections of the arc are column. The last mentioned values were obtained from spectroscopic photographs. From the measured quantities, the following values were calculated: the heat flux into the anode surface, the heat loss of the anode by radiation and conduction, and the heat which was regeneratively transported by the cooling gas back into the arc space. Heat balances for the anode were also obtained. The anode losses (which are approximately 80% of the total arc power for free burning arcs) were reduced by transpiration cooling to 20%. The physical processes of the energy transfer from the arc to the anode are discussed qualitatively.

Study of Federal technology transfer activities in areas of interest to NASA Office of Space and Terrestrial Applications

NASA Technical Reports Server (NTRS)

Madigan, J. A.; Earhart, R. W.

1978-01-01

Forty-three ongoing technology transfer programs in Federal agencies other than NASA were selected from over 200 current Federal technology transfer activities. Selection was made and specific technology transfer mechanisms utilized. Detailed information was obtained on the selected programs by reviewing published literature, and conducting telephone interviews with each program manager. Specific information collected on each program includes technology areas; user groups, mechanisms employed, duration of program, and level of effort. Twenty-four distinct mechanisms are currently employed in Federal technology transfer activities totaling $260 million per year. Typical applications of each mechanism were reviewed, and caveats on evaluating program effectiveness were discussed. A review of recent federally funded research in technology transfer to state and local governments was made utilizing the Smithsonian Science Information Exchange, and abstracts of interest to NASA were selected for further reference.

Characteristics of future air cargo demand and impact on aircraft development - A report on the Cargo/Logistic Airlift Systems Study /CLASS/ project

NASA Technical Reports Server (NTRS)

Whitehead, A. H., Jr.

1978-01-01

The considered study has been conducted to evaluate the future potential for an advanced air cargo transport. A current operations analysis is discussed, taking into account the traffic structure, modal cost comparisons, terminal operations, containerization, and institutional factors. Attention is also given to case studies, a demand forecast, and an advanced air cargo systems analysis. The effects of potential improvements on reducing costs are shown. Improvement to the current infrastructure can occur from 1978 to 1985 with off-the-shelf technology, which when combined with higher load factors for aircraft and containers, can provide up to a 16 percent reduction in total operating costs and a 15 percent rate reduction. The results of the analysis indicate that the proposed changes in the infrastructure and improved cargo loading efficiencies are as important to improving the airlines' financial posture as is the anticipated large dedicated cargo aircraft.

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

Shi, Zhemin; Department of Physical Electronics, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8552; Taguchi, Dai

The details of turnover process of spontaneous polarization and associated carrier motions in indium-tin oxide/poly-(vinylidene-trifluoroethylene)/pentacene/Au capacitor were analyzed by coupling displacement current measurement (DCM) and electric-field-induced optical second-harmonic generation (EFISHG) measurement. A model was set up from DCM results to depict the relationship between electric field in semiconductor layer and applied external voltage, proving that photo illumination effect on the spontaneous polarization process lied in variation of semiconductor conductivity. The EFISHG measurement directly and selectively probed the electric field distribution in semiconductor layer, modifying the model and revealing detailed carrier behaviors involving photo illumination effect, dipole reversal, and interfacial chargingmore » in the device. A further decrease of DCM current in the low voltage region under illumination was found as the result of illumination effect, and the result was argued based on the changing of the total capacitance of the double-layer capacitors.« less

Retarding potential analyzer for the Pioneer-Venus Orbiter Mission

NASA Technical Reports Server (NTRS)

Knudsen, W. C.; Bakke, J.; Spenner, K.; Novak, V.

1979-01-01

The retarding potential analyzer on the Pioneer-Venus Orbiter Mission has been designed to measure most of the thermal plasma parameters within and near the Venusian ionosphere. Parameters include total ion concentration, concentrations of the more abundant ions, ion temperatures, ion drift velocity, electron temperature, and low-energy (0-50 eV) electron distribution function. To accomplish these measurements on a spinning vehicle with a small telemetry bit rate, several functions, including decision functions not previously used in RPA's, have been developed and incorporated into this instrument. The more significant functions include automatic electrometer ranging with background current compensation; digital, quadratic retarding potential step generation for the ion and low-energy electron scans; a current sampling interval of 2 ms throughout all scans; digital logic inflection point detection and data selection; and automatic ram direction detection. Extensive numerical simulation and plasma chamber tests have been conducted to verify adequacy of the design for the Pioneer Mission.

Assistive technology for ultrasound-guided central venous catheter placement.

PubMed

Ikhsan, Mohammad; Tan, Kok Kiong; Putra, Andi Sudjana

2018-01-01

This study evaluated the existing technology used to improve the safety and ease of ultrasound-guided central venous catheterization. Electronic database searches were conducted in Scopus, IEEE, Google Patents, and relevant conference databases (SPIE, MICCAI, and IEEE conferences) for related articles on assistive technology for ultrasound-guided central venous catheterization. A total of 89 articles were examined and pointed to several fields that are currently the focus of improvements to ultrasound-guided procedures. These include improving needle visualization, needle guides and localization technology, image processing algorithms to enhance and segment important features within the ultrasound image, robotic assistance using probe-mounted manipulators, and improving procedure ergonomics through in situ projections of important information. Probe-mounted robotic manipulators provide a promising avenue for assistive technology developed for freehand ultrasound-guided percutaneous procedures. However, there is currently a lack of clinical trials to validate the effectiveness of these devices.

Analog and RF performance of a multigate FinFET at nano scale

NASA Astrophysics Data System (ADS)

Kumar, Abhishek

2016-12-01

In this paper, analog and RF performance of the Fin field effect transistor (FET) at Nano scale is observed through 3D simulation. FinFET devices like rectangular gate all around (RE-GAA) FinFET, cylindrical gate all around (CY-GAA) FinFET and triple gate (TG) FinFET are observed. The figure of merit (FOMs) such as input-output characteristics, trans-conductance (gm), output-conductance (gd), intrinsic gain (gm/gd), gate capacitance (gate to source and total gate capacitance), unity gain cut-off frequency (ft), trans-conductance generation factor (TGF), gain frequency product (GFP), gain bandwidth product (GBP) and gain transconductance frequency product (GTFP) are observed. The analog performance of a FinFETs are observed by realising source follower circuit with NMOS transistor as a current source. The source follower circuit gain is observed. It has been observed that maximum capacitance is observed in case gate all around condition. Rectangular gate all around has the highest transconductance. In the source follower circuit, the gain curve (Vout/Vin) is sharper for TG-FinFET.

Evaluation of a novel chemical sensor system to detect clinical mastitis in bovine milk.

PubMed

Mottram, Toby; Rudnitskaya, Alisa; Legin, Andrey; Fitzpatrick, Julie L; Eckersall, P David

2007-05-15

Automatic detection of clinical mastitis is an essential part of high performance and robotic milking. Currently available technology (conductivity monitoring) is unable to achieve acceptable specificity or sensitivity of detection of clinical mastitis or other clinical diseases. Arrays of sensors with high cross-sensitivity have been successfully applied for recognition and quantitative analysis of other multicomponent liquids. An experiment was conducted to determine whether a multisensor system ("electronic tongue") based on an array of chemical sensors and suitable data processing could be used to discriminate between milk secretions from infected and healthy glands. Measurements were made with a multisensor system of milk samples from two different farms in two experiments. A total of 67 samples of milk from both mastitic and healthy glands were in two sets. It was demonstrated that the multisensor system could distinguish between control and clinically mastitic milk samples (p=0.05). The sensitivity and specificity of the sensor system (93 and 96% correspondingly) showed an improvement over conductivity (56 and 82% correspondingly). The multisensor system offers a novel method of improving mastitis detection.

An estimate of the percentage of non-predatory dead variability in coastal zooplankton of the southern Humboldt Current System.

PubMed

Krautz, M C; Hernández-Miranda, E; Veas, R; Bocaz, P; Riquelme, P; Quiñones, R A

2017-12-01

Non-predatory dead variability in zooplankton remains poorly quantified worldwide. Here, we make the first estimation of the percentage of dead organisms in coastal zooplankton communities in the Humboldt Current System (HCS) under in situ conditions. The study was conducted in four coastal sites of the southern HCS (between 36 and 37°S) over a period of one year. Percentages of dead organisms were based on the classification as live or dead of 158,220 holoplankton and 17,591 meroplankton individuals using neutral red staining technique. The percentage of dead organisms in total-zooplankton was between 4.3% in Coronel Bay (summer) and 76.9% in Llico (autumn). The percentage of dead total-holoplankton varied from 4.2% (Itata River Mouth; autumn) to 77.6% (Llico; autumn), while the percentage of dead total-meroplankton ranged from 1.5% to 56.8% in Coronel Bay and Coliumo Bay, respectively. The most abundant taxa analyzed were the copepods Acartia sp., Paracalanus sp., Calanoides sp., Cladocera, Polychaeta, and the eggs of anchoveta Engraulis ringens. Among these taxa, there was a high degree of interspecific variability in the estimation of the dead organisms. The Pearson correlation shows significant relationships between maximum temperature, and minimum salinity, with the percentage of dead individuals of Acartia sp. and Paracalanus sp. Environmental factors explaining those relationships were: the El Niño 2015-2016 event, and freshwater river runoff. The use of vital staining to estimate non-predatory death for total-zooplankton and selected sentinel species is a promising tool to establish baselines to evaluate natural perturbations (e.g. ENSO), and anthropogenic alterations in coastal pelagic ecosystems. Copyright © 2017 Elsevier Ltd. All rights reserved.

Investigating Cortisol Production and Pattern as Mediators in the Relationship Between Shift Work and Cardiometabolic Risk.

PubMed

Ritonja, Jennifer; Aronson, Kristan J; Day, Andrew G; Korsiak, Jill; Tranmer, Joan

2018-05-01

Shift work is a risk factor for many diseases, including cardiovascular disease. Although the biological pathways are still unclear, it is hypothesized that cortisol disruption during night work is an intermediate. The objective of this study is to determine whether total cortisol production and cortisol pattern mediate the relationship between current shift work and cardiometabolic risk (CMR) among female hospital employees. A cross-sectional study was conducted among 326 female employees (166 rotating shift workers, 160 day workers), recruited from a hospital in Southeastern Ontario, Canada, during 2011 to 2014. Participants completed a baseline interview, questionnaire, and clinical exam. Urine samples were collected over two 24-hour periods and used to analyze creatinine-adjusted cortisol, which was then used to calculate total cortisol production (AUC G ), and pattern (AUC I ). Mediation analysis was performed to test the mediating effect of cortisol in the relationship between shift work and a continuous CMR score. Current shift work is associated with a 0.52 higher CMR score (95% CI: 0.15, 0.89), a lower cortisol output (AUC G ), and a flatter pattern (AUC I ) over a 2-day period. AUC G is a partial mediator in the relationship between shift work and CMR, whereas AUC I is not. AUC G is also associated with CMR while controlling for shift work, suggesting that lower total cortisol production is also linked to CMR in non-shift workers. Total cortisol production is a partial mediator in the relationship between rotating shift work and CMR among female hospital employees, whereas cortisol pattern is not a mediator. Copyright © 2018 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Quantitative image reconstruction for total-body PET imaging using the 2-meter long EXPLORER scanner

NASA Astrophysics Data System (ADS)

Zhang, Xuezhu; Zhou, Jian; Cherry, Simon R.; Badawi, Ramsey D.; Qi, Jinyi

2017-03-01

The EXPLORER project aims to build a 2 meter long total-body PET scanner, which will provide extremely high sensitivity for imaging the entire human body. It will possess a range of capabilities currently unavailable to state-of-the-art clinical PET scanners with a limited axial field-of-view. The huge number of lines-of-response (LORs) of the EXPLORER poses a challenge to the data handling and image reconstruction. The objective of this study is to develop a quantitative image reconstruction method for the EXPLORER and compare its performance with current whole-body scanners. Fully 3D image reconstruction was performed using time-of-flight list-mode data with parallel computation. To recover the resolution loss caused by the parallax error between crystal pairs at a large axial ring difference or transaxial radial offset, we applied an image domain resolution model estimated from point source data. To evaluate the image quality, we conducted computer simulations using the SimSET Monte-Carlo toolkit and XCAT 2.0 anthropomorphic phantom to mimic a 20 min whole-body PET scan with an injection of 25 MBq 18F-FDG. We compare the performance of the EXPLORER with a current clinical scanner that has an axial FOV of 22 cm. The comparison results demonstrated superior image quality from the EXPLORER with a 6.9-fold reduction in noise standard deviation comparing with multi-bed imaging using the clinical scanner.

Quantitative Image Reconstruction for Total-Body PET Imaging Using the 2-meter Long EXPLORER Scanner

PubMed Central

Zhang, Xuezhu; Zhou, Jian; Cherry, Simon R.; Badawi, Ramsey D.

2017-01-01

The EXPLORER project aims to build a 2-meter long total-body PET scanner, which will provide extremely high sensitivity for imaging the entire human body. It will possess a range of capabilities currently unavailable to state-of-the-art clinical PET scanners with a limited axial field-of-view. The huge number of lines-of-response (LORs) of the EXPLORER poses a challenge to the data handling and image reconstruction. The objective of this study is to develop a quantitative image reconstruction method for the EXPLORER and compare its performance with current whole-body scanners. Fully 3D image reconstruction was performed using time-of-flight list-mode data with parallel computation. To recover the resolution loss caused by the parallax error between crystal pairs at a large axial ring difference or transaxial radial offset, we applied an image domain resolution model estimated from point source data. To evaluate the image quality, we conducted computer simulations using the SimSET Monte-Carlo toolkit and XCAT 2.0 anthropomorphic phantom to mimic a 20-minute whole-body PET scan with an injection of 25 MBq 18F-FDG. We compare the performance of the EXPLORER with a current clinical scanner that has an axial FOV of 22 cm. The comparison results demonstrated superior image quality from the EXPLORER with a 6.9-fold reduction in noise standard deviation comparing with multi-bed imaging using the clinical scanner. PMID:28240215

Evaluation of Total Dissolved Solids and Specific Conductance Water Quality Targets with Paired Single-Species and Mesocosm Community Exposures

EPA Science Inventory

Isolated single-species exposures were conducted in parallel with 42 d mesocosm dosing studies that measured in-situ and whole community responses to different recipes of excess total dissolved solids (TDS). The studies were conducted with cultured species and native taxa from mo...

Field-aligned current associated with a distorted two-cell convection pattern during northward interplanetary magnetic field

NASA Technical Reports Server (NTRS)

Zhu, L.; Schunk, R. W.; Sojka, J. J.

1991-01-01

The influence of the ionospheric conductance on the field-aligned current associated with a distorted two-cell convection pattern during northward IMF was investigated using the Heppner-Maynard (1987) convection model and the Utah State University conductivity model described by Rasmussen and Schunk (1987). Results show that the variation of the ionospheric conductivity distribution can significantly affect the features of the field-aligned current for northward IMF, where matching or mismatching between the conductance gradient and the convection electric field plays a key role. It was found that the increase of the field-aligned current in the polar cap observed during summer is mainly due to the increasing contribution from the Pedersen current, and that the increase of the field-aligned current in both the oval region and the evening-midnight sector during the active aurora period is mainly due to the increasing contribution from the Hall current.

Experimental and numerical study of a dual configuration for a flapping tidal current generator.

PubMed

Kim, Jihoon; Quang Le, Tuyen; Hwan Ko, Jin; Ebenezer Sitorus, Patar; Hartarto Tambunan, Indra; Kang, Taesam

2015-07-30

In this study, we conduct experimental and consecutive numerical analyses of a flapping tidal current generator with a mirror-type dual configuration with front-swing and rear-swing flappers. An experimental analysis of a small-scale prototype is conducted in a towing tank, and a numerical analysis is conducted by means of two-dimensional computational fluid dynamics simulations with an in-house code. An experimental study with a controller to determine the target arm angle shows that the resultant arm angle is dependent on the input arm angle, the frequency, and the applied load, while a high pitch is obtained simply with a high input arm angle. Through a parametric analysis conducted while varying these factors, a high applied load and a high input arm angle were found to be advantageous. Moreover, the optimal reduced frequency was found to be 0.125 in terms of the power extraction. In consecutive numerical investigations with the kinematics selected from the experiments, it was found that a rear-swing flapper contributes to the total amount of power more than a front-swing flapper with a distance of two times the chord length and with a 90° phase difference between the two. The high contribution stems from the high power generated by the rear-swing flapper, which mimics the tail fin movement of a dolphin along a flow, compared to a plunge system or a front-swing system, which mimics the tail fin movement of a dolphin against a flow. It is also due to the fact that the shed vorticities of the front-swing flapper slightly affect negatively or even positively the power performance of the rear-swing system at a given distance and phase angle.

Landslide Susceptibility Assessment Using Spatial Multi-Criteria Evaluation Model in Rwanda.

PubMed

Nsengiyumva, Jean Baptiste; Luo, Geping; Nahayo, Lamek; Huang, Xiaotao; Cai, Peng

2018-01-31

Landslides susceptibility assessment has to be conducted to identify prone areas and guide risk management. Landslides in Rwanda are very deadly disasters. The current research aimed to conduct landslide susceptibility assessment by applying Spatial Multi-Criteria Evaluation Model with eight layers of causal factors including: slope, distance to roads, lithology, precipitation, soil texture, soil depth, altitude and land cover. In total, 980 past landslide locations were mapped. The relationship between landslide factors and inventory map was calculated using the Spatial Multi-Criteria Evaluation. The results revealed that susceptibility is spatially distributed countrywide with 42.3% of the region classified from moderate to very high susceptibility, and this is inhabited by 49.3% of the total population. In addition, Provinces with high to very high susceptibility are West, North and South (40.4%, 22.8% and 21.5%, respectively). Subsequently, the Eastern Province becomes the peak under low susceptibility category (87.8%) with no very high susceptibility (0%). Based on these findings, the employed model produced accurate and reliable outcome in terms of susceptibility, since 49.5% of past landslides fell within the very high susceptibility category, which confirms the model's performance. The outcomes of this study will be useful for future initiatives related to landslide risk reduction and management.

Deep electrical investigations in the Long Valley geothermal area, California

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

Stanley, W.D.; Jackson, D.B.; Zohdy, A.A.R.

1976-02-10

Direct current resistivity and time domain electromagnetic techniques were used to study the electrical structure of the Long Valley geothermal area. A resistivity map was compiled from 375 total field resistivity measurements. Two significant zones of low resistivity were detected, one near Casa Diablo Hot Springs and one surrounding the Cashbaugh Ranch-Whitmore Hot Springs area. These anomalies and other parts of the caldera were investigated in detail with 49 Schlumberger dc soundings and 13 transient electromagnetic soundings. An extensive conductive zone of 1- to 10-..cap omega..m resistivity was found to be the cause of the total field resistivity lows. Drillmore » hole information indicates that the shallow parts of the conductive zone in the eastern part of the caldera contain water of only 73/sup 0/C and consist of highly zeolitized tuffs and ashes in the places that were tested. A deeper zone near Whitmore Hot Springs is somewhat more promising in potential for hot water, but owing to the extensive alteration prevalent in the caldera the presence of hot water cannot be definitely assumed. The resistivity results indicate that most of the past hydrothermal activity, and probably most of the present activity, is controlled by fracture systems related to regional Sierran faulting.« less

Prevalence of migraine and co-morbid psychiatric disorders among students of Cumhuriyet University.

PubMed

Semiz, Murat; Şentürk, Ilteriş Ahmet; Balaban, Hatice; Yağız, Ayşegül Kartal; Kavakçı, Önder

2013-04-11

The aim of this study was to investigate the prevalence of migraine and associated psychiatric disorders among university students at Cumhuriyet University of Sivas in Turkey. A total of 1601 university students participated in this study and answered the questionnaires. The study was conducted in three stages: the self-questionnaire, the neurological evaluation, and the psychiatric evaluation. In the first stage, the subjects completed a questionnaire to assess migraine symptoms. In the second stage, the subjects who reported having migraines underwent a detailed neurological evaluation conducted by a neurologist to confirm the diagnosis. In the final stage, the subjects with migraines completed a psychiatric examination using the structured clinical interview for DSM IV-R Axis I. The self-reported migraine prevalence rate was 13.7%, and the actual prevalence rate of migraine among the university students was calculated to be 10.6% (n=169). When the results obtained with the SCID-I were examined, a current SCID-I psychiatric diagnosis was found in 39 (23.1%) of the 169 subjects with migraines. A total of 73 (43.2%) students with migraines had a lifetime SCID-I psychiatric diagnosis. The results of this study indicate that migraines were highly prevalent among university students in Turkey with comorbid psychiatric disorders. Treatment strategies must be developed to manage these comorbidities.

The U.S. Geological Survey Federal-State Cooperative Water- Resources Program: Fiscal Year 1988

USGS Publications Warehouse

Gilbert, Bruce K.; Mann, William B.

1989-01-01

The Federal-State Cooperative Program is a partnership between the U.S. Geological Survey and State and local agencies. It provides a balanced approach to the study and resolution of water-related problems and to acquiring hydrologic data. The principal program objectives are to: (1) collect, on a systematic basis, data needed for the continuing determination and evaluation of the quantity, quality, and use of the Nation's water resources, and (2) appraise the availability and the physical, chemical, and biological characteristics of surface and ground water through analytical and interpretive investigations. During fiscal year 1988, hydrologic data collection, interpretive investigations, and research were conducted by Geological Survey personnel in offices in every State, Puerto Rico, and several territories in cooperation with more than 1,000 local, State, and regional agencies. In fiscal year 1988, Federal funding of almost $60 million was matched by cooperating agencies, who also provided approximately $6 million unmatched for a total program of about $126 million. This amounted to more than 40 percent of the total funds for Geological Survey water-resources activities. This report presents examples of current (1988) investigations. It also lists about 250 water-resources investigations related to agricultural activities that the Geological Survey conducted from 1970 to 1988.

Landslide Susceptibility Assessment Using Spatial Multi-Criteria Evaluation Model in Rwanda

PubMed Central

Nsengiyumva, Jean Baptiste; Luo, Geping; Nahayo, Lamek; Huang, Xiaotao; Cai, Peng

2018-01-01

Landslides susceptibility assessment has to be conducted to identify prone areas and guide risk management. Landslides in Rwanda are very deadly disasters. The current research aimed to conduct landslide susceptibility assessment by applying Spatial Multi-Criteria Evaluation Model with eight layers of causal factors including: slope, distance to roads, lithology, precipitation, soil texture, soil depth, altitude and land cover. In total, 980 past landslide locations were mapped. The relationship between landslide factors and inventory map was calculated using the Spatial Multi-Criteria Evaluation. The results revealed that susceptibility is spatially distributed countrywide with 42.3% of the region classified from moderate to very high susceptibility, and this is inhabited by 49.3% of the total population. In addition, Provinces with high to very high susceptibility are West, North and South (40.4%, 22.8% and 21.5%, respectively). Subsequently, the Eastern Province becomes the peak under low susceptibility category (87.8%) with no very high susceptibility (0%). Based on these findings, the employed model produced accurate and reliable outcome in terms of susceptibility, since 49.5% of past landslides fell within the very high susceptibility category, which confirms the model’s performance. The outcomes of this study will be useful for future initiatives related to landslide risk reduction and management. PMID:29385096

Comparative analysis of discharges into Lake Michigan, Phase I - Southern Lake Michigan.

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

Veil, J. A.; Elcock, D.; Gasper, J. R.

2008-06-30

BP Products North America Inc. (BP) owns and operates a petroleum refinery located on approximately 1,700 acres in Whiting, East Chicago, and Hammond, Indiana, near the southern tip of Lake Michigan. BP provided funding to Purdue University-Calumet Water Institute (Purdue) and Argonne National Laboratory (Argonne) to conduct studies related to wastewater treatment and discharges. Purdue and Argonne are working jointly to identify and characterize technologies that BP could use to meet the previous discharge permit limits for total suspended solids (TSS) and ammonia after refinery modernization. In addition to the technology characterization work, Argonne conducted a separate project task, whichmore » is the subject of this report. In Phase I of a two-part study, Argonne estimated the current levels of discharge to southern Lake Michigan from significant point and nonpoint sources in Illinois, Indiana, and portions of Michigan. The study does not consider all of the chemicals that are discharged. Rather, it is narrowly focused on a selected group of pollutants, referred to as the 'target pollutants'. These include: TSS, ammonia, total and hexavalent chromium, mercury, vanadium, and selenium. In Phase II of the study, Argonne will expand the analysis to cover the entire Lake Michigan drainage basin.« less

Thermal imaging diagnostics of high-current electron beams.

PubMed

Pushkarev, A; Kholodnaya, G; Sazonov, R; Ponomarev, D

2012-10-01

The thermal imaging diagnostics of measuring pulsed electron beam energy density is presented. It provides control of the electron energy spectrum and a measure of the density distribution of the electron beam cross section, the spatial distribution of electrons with energies in the selected range, and the total energy of the electron beam. The diagnostics is based on the thermal imager registration of the imaging electron beam thermal print in a material with low bulk density and low thermal conductivity. Testing of the thermal imaging diagnostics has been conducted on a pulsed electron accelerator TEU-500. The energy of the electrons was 300-500 keV, the density of the electron current was 0.1-0.4 kA/cm(2), the duration of the pulse (at half-height) was 60 ns, and the energy in the pulse was up to 100 J. To register the thermal print, a thermal imager Fluke-Ti10 was used. Testing showed that the sensitivity of a typical thermal imager provides the registration of a pulsed electron beam heat pattern within one pulse with energy density over 0.1 J/cm(2) (or with current density over 10 A/cm(2), pulse duration of 60 ns and electron energy of 400 keV) with the spatial resolution of 0.9-1 mm. In contrast to the method of using radiosensitive (dosimetric) materials, thermal imaging diagnostics does not require either expensive consumables, or plenty of processing time.

Effects of pipette modulation and imaging distances on ion currents measured with scanning ion conductance microscopy (SICM).

PubMed

Chen, Chiao-Chen; Baker, Lane A

2011-01-07

Local conductance variations can be estimated by measuring ion current magnitudes with scanning ion conductance microscopy (SICM). Factors which influence image quality and quantitation of ion currents measured with SICM have been evaluated. Specifically, effects of probe-sample separation and pipette modulation have been systematically studied for the case of imaging conductance variations at pores in a polymer membrane under transmembrane concentration gradients. The influence of probe-sample separation on ion current images was evaluated using distance-modulated (ac) feedback. Approach curves obtained using non-modulated (dc) feedback were also recorded to determine the relative influence of pipette-generated convection by comparison of ion currents measured with both ac and dc feedback modes. To better interpret results obtained, comparison to a model based on a disk-shaped geometry for nanopores in the membrane, as well as relevant position-dependent parameters of the experiment is described. These results advance our current understanding of conductance measurements with SICM.

Multi-objective optimization design and experimental investigation of centrifugal fan performance

NASA Astrophysics Data System (ADS)

Zhang, Lei; Wang, Songling; Hu, Chenxing; Zhang, Qian

2013-11-01

Current studies of fan performance optimization mainly focus on two aspects: one is to improve the blade profile, and another is only to consider the influence of single impeller structural parameter on fan performance. However, there are few studies on the comprehensive effect of the key parameters such as blade number, exit stagger angle of blade and the impeller outlet width on the fan performance. The G4-73 backward centrifugal fan widely used in power plants is selected as the research object. Based on orthogonal design and BP neural network, a model for predicting the centrifugal fan performance parameters is established, and the maximum relative errors of the total pressure and efficiency are 0.974% and 0.333%, respectively. Multi-objective optimization of total pressure and efficiency of the fan is conducted with genetic algorithm, and the optimum combination of impeller structural parameters is proposed. The optimized parameters of blade number, exit stagger angle of blade and the impeller outlet width are seperately 14, 43.9°, and 21 cm. The experiments on centrifugal fan performance and noise are conducted before and after the installation of the new impeller. The experimental results show that with the new impeller, the total pressure of fan increases significantly in total range of the flow rate, and the fan efficiency is improved when the relative flow is above 75%, also the high efficiency area is broadened. Additionally, in 65% -100% relative flow, the fan noise is reduced. Under the design operating condition, total pressure and efficiency of the fan are improved by 6.91% and 0.5%, respectively. This research sheds light on the considering of comprehensive effect of impeller structrual parameters on fan performance, and a new impeller can be designed to satisfy the engineering demand such as energy-saving, noise reduction or solving air pressure insufficiency for power plants.

Anxiety, Depression and Quality of Life in Breast Cancer Patients in the Levant

PubMed Central

Akel, Reem; El Darsa, Haidar; Anouti, Bilal; Mukherji, Deborah; Temraz, Sally; Raslan, Rasha; Tfayli, Arafat; Assi, Hazem

2017-01-01

Background: Limited data are currently available regarding the psychological well-being and quality of life of breast cancer patients after active treatment in Lebanon and the Arab region in general. The objective of this study was to determine the prevalence of anxiety and depression among Arab breast cancer patients and assess the quality of life with reference to socio-demographic and clinical characteristics. Methods: This cross-sectional study was conducted among female breast cancer patients diagnosed between January 2009 and March 2014, who were recruited from the outpatient clinics of Naef K. Basile Cancer Institute at the American University of Beirut Medical Center (AUBMC) from November 2015 till December 2016. An interview was conducted utilizing two validated questionnaires: the Hospital Anxiety and Depression Scale (HADS) and the Functional Assessment of Cancer Therapy-Breast (FACT-B). Socio-demographic and clinical characteristics that might predict patient quality of life were collected and summarized. Results: A total of 150 patients were interviewed (median age 53.5±10.4 years). Most were assessed 3 to 5 years (68.7%) after initial diagnosis and had undergone surgery, chemotherapy, radiation, or hormonal therapy (97.3%, 79.3%, 80.7% and 86.0%, respectively). The median total HADS score was 10.0 ± 8.0, with approximately 41.3% of study participants having abnormal scores on the anxiety subscale and 24.7% on the depression subscale. Significant predictors of total HADS score were nationality and level of education (p=0.001, p=0.001 respectively; R2=0.181). Participants who were Iraqi, had stage IV disease, had a household monthly income below 1000 USD, or had received chemotherapy exhibited significantly lower total FACT-B scores, these being highly negatively correlated with total HADS scores (rs= -0.73, p=0.001). Conclusion: There is a vital need for the development of individualized interventions and psychosocial support programs tailored to the physical and psychological well-being of breast cancer patients in the Levant region. PMID:29072421

Performance, Facility Pressure Effects, and Stability Characterization Tests of NASA's Hall Effect Rocket with Magnetic Shielding Thruster

NASA Technical Reports Server (NTRS)

Kamhawi, Hani; Huang, Wensheng; Haag, Thomas; Yim, John; Herman, Daniel; Peterson, Peter Y.; Williams, George J.; Gilland, James; Hofer, Richard; Mikellides, Ioannis

2016-01-01

NASA's Hall Effect Rocket with Magnetic Shielding (HERMeS) 12.5 kW Technology Demonstration Unit-1 (TDU-1) has been the subject of extensive technology maturation in preparation for flight system development. Part of the technology maturation effort included experimental evaluation of the TDU-1 thruster with conducting and dielectric front pole cover materials in two different electrical configurations. A graphite front magnetic pole cover thruster configuration with the thruster body electrically tied to cathode, and an alumina front pole cover thruster configuration with the thruster body floating were evaluated. Both configurations were also evaluated at different facility background pressure conditions to evaluate background pressure effects on thruster operation. Performance characterization tests found that higher thruster performance was attained with the graphite front pole cover configuration with the thruster electrically tied to cathode. A total thrust efficiency of 68% and a total specific impulse of 2,820 s was demonstrated at a discharge voltage of 600 V and a discharge power of 12.5 kW. Thruster stability regimes were characterized with respect to the thruster discharge current oscillations and with maps of the discharge current-voltage-magnetic field (IVB). Analysis of TDU-1 discharge current waveforms found that lower normalized discharge current peak-to-peak and root mean square magnitudes were attained when the thruster was electrically floated with alumina front pole covers. Background pressure effects characterization tests indicated that the thruster performance and stability were mostly invariant to changes in the facility background pressure for vacuum chamber pressure below 1×10-5 Torr-Xe (for thruster flow rates of 20.5 mg/s). Power spectral density analysis of the discharge current waveforms showed that increasing the vacuum chamber background pressure resulted in a higher discharge current dominant breathing mode frequency. Finally, IVB maps of the TDU-1 thruster indicated that the discharge current became more oscillatory with higher discharge current peak-to-peak and RMS values with increased facility background pressure at lower thruster mass flow rates; thruster operation at higher flow rates resulted in less change to the thruster's IVB characteristics with elevated background pressure.

Conductivity Variation Observed by Polarization and Depolarization Current Measurements of High-Voltage Equipment Insulation System

NASA Astrophysics Data System (ADS)

Jamail, Nor Akmal Mohd; Piah, Mohamed Afendi Mohamed; Muhamad, Nor Asiah

2012-09-01

Nondestructive and time domain dielectric measurement techniques such as polarization and depolarization current (PDC) measurements have recently been widely used as a potential tool for determining high-voltage insulation conditions by analyzing the insulation conductivity. The variation in the conductivity of an insulator was found to depend on several parameters: the difference between the polarization and depolarization currents, geometric capacitance, and the relative permittivity of the insulation material. In this paper the conductivities of different types of oil-paper insulation material are presented. The insulation conductivities of several types of electrical apparatus were simulated using MATLAB. Conductivity insulation was found to be high at high polarizations and at the lowest depolarization current. It was also found to increase with increasing relative permittivity as well as with decreasing geometric capacitance of the insulating material.

Electric rail gun projectile acceleration to high velocity

NASA Technical Reports Server (NTRS)

Bauer, D. P.; Mccormick, T. J.; Barber, J. P.

1982-01-01

Electric rail accelerators are being investigated for application in electric propulsion systems. Several electric propulsion applications require that the rail accelerator be capable of launching projectiles at velocities above 10 km/s. An experimental program was conducted to develop rail accelerator technology for high velocity projectile launch. Several 6 mm bore, 3 m long rail accelerators were fabricated. Projectiles with a mass of 0.2 g were accelerated by plasmas, carrying currents up to 150 kA. Experimental design and results are described. Results indicate that the accelerator performed as predicted for a fraction of the total projectile acceleration. The disparity between predicted and measured results are discussed.

Energy from wood waste - A case study

NASA Technical Reports Server (NTRS)

Scola, R.; Daughtrey, K.

1980-01-01

A joint study has been conducted by NASA and Army installations collocated in a dense forest in southwestern Mississippi in order to determine the technical and economic feasibility of using wood waste as a renewable energy source. The study has shown that, with proper forest management, the timber on government lands could eventually support the total energy requirements of 832 billion Btu/yr. Analysis of the current conversion technologies indicates that the direct combustion spreader stoker approach is the best demonstrated technology for this specific application. The economics of the individual powerplants reveal them as attractive alternatives to fossil fueled plants. Environmental aspects are also discussed.

Entrainment of viruses from septic tank leach fields through a shallow, sandy soil aquifer.

PubMed

Vaughn, J M; Landry, E F; Thomas, M Z

1983-05-01

A study was conducted which focused on movement of naturally occurring human enteroviruses from a subsurface wastewater disposal system through a shallow aquifer. The potential for significant entrainment of virus particles was evidenced by their recovery at down-gradient distances of 67.05 m and from aquifer depths of 18 m. A significant negative correlation was observed between virus occurrence and the distance from the "septage" (leaching pool) source. Virus occurrence could not be statistically correlated with either total or fecal coliforms, indicating the limitations of current microbial water quality indicators for predicting the virological quality of groundwater.

Persistent optimizing: how mothers make food choices for their preschool children.

PubMed

Walsh, Audrey; Meagher-Stewart, Donna; Macdonald, Marilyn

2015-04-01

Mothers' ability to provide healthy food choices for their children has become more complex in our current obesogenic environment. We conducted a total of 35 interviews with 18 mothers of preschool children. Using constructivist grounded theory methods, we developed a substantive theory of how mothers make food choices for their preschoolers. Our substantive theory, persistent optimizing, consists of three main integrated conceptual categories: (a) acknowledging contextual constraints, (b) stretching boundaries, and (c) strategic positioning. Implications to improve mothers' ability to make healthy food choices that reduce their children's risk of becoming overweight or obese are discussed. © The Author(s) 2014.

Development of optimum process for electron beam cross-linking of high density polyethylene thermal energy storage pellets, process scale-up and production of application qualities of material

NASA Technical Reports Server (NTRS)

Salyer, I. O.

1980-01-01

The electron irradiation conditions required to prepare thermally from stable high density polyethylene (HDPE) were defined. The conditions were defined by evaluating the heat of fusion and the melting temperature of several HDPE specimens. The performance tests conducted on the specimens, including the thermal cycling tests in the thermal energy storage unit are described. The electron beam irradiation tests performed on the specimens, in which the total radiation dose received by the pellets, the electron beam current, the accelerating potential, and the atmospheres were varied, are discussed.

Environmental characteristics of anopheline mosquito larval habitats in a malaria endemic area in Iran.

PubMed

Soleimani-Ahmadi, Moussa; Vatandoost, Hassan; Hanafi-Bojd, Ahmad-Ali; Zare, Mehdi; Safari, Reza; Mojahedi, Abdolrasul; Poorahmad-Garbandi, Fatemeh

2013-07-01

To determine the effects of environmental parameters of larval habitats on distribution and abundance of anopheline mosquitoes in Rudan county of Iran. This cross-sectional study was conducted during the mosquito breeding season from February 2010 to October 2011. The anopheline larvae were collected using the standard dipping method. The specimens were identified using a morphological-based key. Simultaneously with larval collection, environmental parameters of the larval habitats including water current and turbidity, sunlight situation, and substrate type of habitats were recorded. Water samples were taken from breeding sites during larval collection. Before collection of samples, the water temperature was measured. The water samples were analysed for turbidity, conductivity, total alkalinity, total dissolved solid, pH and ions including chloride, sulphate, calcium, and magnesium. Statistical correlation analysis and ANOVA test were used to analyze the association between environmental parameters and larval mosquito abundance. In total 2 973 larvae of the genus Anopheles were collected from 25 larval habitats and identified using morphological characters. They comprised of six species: An. dthali (53.21%), An. stephensi (24.22%), An. culicifacies (14.06%), An. superpictus (4.07%), An. turkhudi (3.30%), and An. apoci (1.14%). The most abundant species was An. dthali which were collected from all of the study areas. Larvae of two malaria vectors, An. dthali and An. stephensi, co-existed and collected in a wide range of habitats with different physico-chemical parameters. The most common larval habitats were man-made sites such as sand mining pools with clean and still water. The anopheline mosquitoes also preferred permanent habitats in sunlight with sandy substrates. The results indicated that there was a significant relationship between mean physico-chemical parameters such as water temperature, conductivity, total alkalinity, sulphate, chloride, and mosquito distribution and abundance. The results of this study showed a correlation between certain environmental parameters and mosquito larvae abundance, and these parameters should be considered in planning and implementing larval control programs. Copyright © 2013 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Iberiotoxin-sensitive and -insensitive BK currents in Purkinje neuron somata

PubMed Central

Benton, Mark D.; Lewis, Amanda H.; Bant, Jason S.

2013-01-01

Purkinje cells have specialized intrinsic ionic conductances that generate high-frequency action potentials. Disruptions of their Ca or Ca-activated K (KCa) currents correlate with altered firing patterns in vitro and impaired motor behavior in vivo. To examine the properties of somatic KCa currents, we recorded voltage-clamped KCa currents in Purkinje cell bodies isolated from postnatal day 17–21 mouse cerebellum. Currents were evoked by endogenous Ca influx with approximately physiological Ca buffering. Purkinje somata expressed voltage-activated, Cd-sensitive KCa currents with iberiotoxin (IBTX)-sensitive (>100 nS) and IBTX-insensitive (>75 nS) components. IBTX-sensitive currents activated and partially inactivated within milliseconds. Rapid, incomplete macroscopic inactivation was also evident during 50- or 100-Hz trains of 1-ms depolarizations. In contrast, IBTX-insensitive currents activated more slowly and did not inactivate. These currents were insensitive to the small- and intermediate-conductance KCa channel blockers apamin, scyllatoxin, UCL1684, bicuculline methiodide, and TRAM-34, but were largely blocked by 1 mM tetraethylammonium. The underlying channels had single-channel conductances of ∼150 pS, suggesting that the currents are carried by IBTX-resistant (β4-containing) large-conductance KCa (BK) channels. IBTX-insensitive currents were nevertheless increased by small-conductance KCa channel agonists EBIO, chlorzoxazone, and CyPPA. During trains of brief depolarizations, IBTX-insensitive currents flowed during interstep intervals, and the accumulation of interstep outward current was enhanced by EBIO. In current clamp, EBIO slowed spiking, especially during depolarizing current injections. The two components of BK current in Purkinje somata likely contribute differently to spike repolarization and firing rate. Moreover, augmentation of BK current may partially underlie the action of EBIO and chlorzoxazone to alleviate disrupted Purkinje cell firing associated with genetic ataxias. PMID:23446695

Properties of Air Traffic Conflicts for Free and Structured Routing

NASA Technical Reports Server (NTRS)

Bilimoria, Karl D.; Lee, Hilda Q.

2001-01-01

This paper analyzes the properties of air traffic conflicts in a future free routing system against those in the current structured routing system. Simulation of en route air traffic operations (above 18,000 ft) over the contiguous United States for a 24-hour period, constructed with initial conditions from actual air traffic data, were conducted using the Future ATM Concepts Evaluation Tool (FACET). Free routes were modeled as great circle (direct) routes from origin to destination, and structured routes were derived from actual flight plans along the current system of air routes. The conflict properties analyzed in this study include: (1) Total number of conflicts; (2) Distributions of key conflict parameters; and, (3) Categorization of conflicts into independent conflicts and two types of interacting conflicts. Preliminary results (for Denver Center traffic) indicate that conflict properties in a free routing system are different from those in the current structured routing system. In particular, a free routing system has significantly fewer conflicts, involving a correspondingly smaller number of aircraft, compared to the current structured routing system. Additionally, the conflict parameter distributions indicate that free routing conflicts are less intrusive than structured routing conflicts, and would therefore require small trajectory deviations for resolution.

Investigation of Passive Filter for LED Lamp

NASA Astrophysics Data System (ADS)

Sarwono, Edi; Facta, Mochammad; Handoko, Susatyo

2017-04-01

Light Emitting Diode lamp or LED lamp is one of the energy saving lamps nowadays widely used by consumers. However, LED lamp has contained harmonics caused by the rectifier circuit inside the lamp. Harmonics cause a quality problem in power system. As the harmonics present in current or voltage, the waveforms are distorted. Harmonics can lead to overheating in magnetic core of electrical equipments. In this paper, several tests are carried out to investigate the harmonic content of voltage and currents, and also the level of light intensity of the two brands of LED lamps. Measurements in this study are conducted by using HIOKI Power Quality Analyzer 3197. The test results show that the total harmonic distortion or THD of voltage on various brands of LED lamps did not exceed 5% as in compliance to the limit of IEEE standard 519-1992. The largest harmonic voltage is 2.9%, while maximum harmonic current for tested brands of LED lamp is 170.6%. The use of low pass filter in the form of LC filter was proposed. Based on experimental results, the application of LC filter at input side of LED lamp has successfully reduced THD current in the range of 85%-88%.

Performance-Enhanced Activated Carbon Electrodes for Supercapacitors Combining Both Graphene-Modified Current Collectors and Graphene Conductive Additive.

PubMed

Wang, Rubing; Qian, Yuting; Li, Weiwei; Zhu, Shoupu; Liu, Fengkui; Guo, Yufen; Chen, Mingliang; Li, Qi; Liu, Liwei

2018-05-15

Graphene has been widely used in the active material, conductive agent, binder or current collector for supercapacitors, due to its large specific surface area, high conductivity, and electron mobility. However, works simultaneously employing graphene as conductive agent and current collector were rarely reported. Here, we report improved activated carbon (AC) electrodes (AC@G@NiF/G) simultaneously combining chemical vapor deposition (CVD) graphene-modified nickel foams (NiF/Gs) current collectors and high quality few-layer graphene conductive additive instead of carbon black (CB). The synergistic effect of NiF/Gs and graphene additive makes the performances of AC@G@NiF/G electrodes superior to those of electrodes with CB or with nickel foam current collectors. The performances of AC@G@NiF/G electrodes show that for the few-layer graphene addition exists an optimum value around 5 wt %, rather than a larger addition of graphene, works out better. A symmetric supercapacitor assembled by AC@G@NiF/G electrodes exhibits excellent cycling stability. We attribute improved performances to graphene-enhanced conductivity of electrode materials and NiF/Gs with 3D graphene conductive network and lower oxidation, largely improving the electrical contact between active materials and current collectors.

Performance-Enhanced Activated Carbon Electrodes for Supercapacitors Combining Both Graphene-Modified Current Collectors and Graphene Conductive Additive

PubMed Central

Wang, Rubing; Qian, Yuting; Li, Weiwei; Zhu, Shoupu; Liu, Fengkui; Guo, Yufen; Chen, Mingliang; Li, Qi; Liu, Liwei

2018-01-01

Graphene has been widely used in the active material, conductive agent, binder or current collector for supercapacitors, due to its large specific surface area, high conductivity, and electron mobility. However, works simultaneously employing graphene as conductive agent and current collector were rarely reported. Here, we report improved activated carbon (AC) electrodes (AC@G@NiF/G) simultaneously combining chemical vapor deposition (CVD) graphene-modified nickel foams (NiF/Gs) current collectors and high quality few-layer graphene conductive additive instead of carbon black (CB). The synergistic effect of NiF/Gs and graphene additive makes the performances of AC@G@NiF/G electrodes superior to those of electrodes with CB or with nickel foam current collectors. The performances of AC@G@NiF/G electrodes show that for the few-layer graphene addition exists an optimum value around 5 wt %, rather than a larger addition of graphene, works out better. A symmetric supercapacitor assembled by AC@G@NiF/G electrodes exhibits excellent cycling stability. We attribute improved performances to graphene-enhanced conductivity of electrode materials and NiF/Gs with 3D graphene conductive network and lower oxidation, largely improving the electrical contact between active materials and current collectors. PMID:29762528

High electric field conduction in low-alkali boroaluminosilicate glass

NASA Astrophysics Data System (ADS)

Dash, Priyanka; Yuan, Mengxue; Gao, Jun; Furman, Eugene; Lanagan, Michael T.

2018-02-01

Electrical conduction in silica-based glasses under a low electric field is dominated by high mobility ions such as sodium, and there is a transition from ionic transport to electronic transport as the electric field exceeds 108 V/m at low temperatures. Electrical conduction under a high electric field was investigated in thin low-alkali boroaluminosilicate glass samples, showing nonlinear conduction with the current density scaling approximately with E1/2, where E is the electric field. In addition, thermally stimulated depolarization current (TSDC) characterization was carried out on room-temperature electrically poled glass samples, and an anomalous discharging current flowing in the same direction as the charging current was observed. High electric field conduction and TSDC results led to the conclusion that Poole-Frenkel based electronic transport occurs in the mobile-cation-depleted region adjacent to the anode, and accounts for the observed anomalous current.

The influence of the breakdown electric field in the configuration of lightning corona sheath on charge distribution in the channel

NASA Astrophysics Data System (ADS)

Ignjatovic, Milan; Cvetic, Jovan; Heidler, Fridolin; Markovic, Slavoljub; Djuric, Radivoje

2014-11-01

A model of corona sheath that surrounds the thin core of the lightning channel has been investigated by using a generalized traveling current source return stroke model. The lightning channel is modeled by a charged corona sheath that stretches around a highly conductive central core through which the main current flows. The channel core with the negatively charged outer channel sheath forms a strong electric field, with an overall radial orientation. The return stroke process is modeled as the negative leader charge in the corona sheath being discharged by the positive charge coming from the channel core. Expressions that describe how the corona sheath radius evolves during the return stroke are obtained from the corona sheath model, which predicts charge motion within the sheath. The corona sheath model, set forth by Maslowski and Rakov (2006), Tausanovic et al. (2010), Marjanovic and Cvetic (2009), Cvetic et al. (2011) and Cvetic et al. (2012), divides the sheath onto three zones: zone 1 (surrounding the channel core with net positive charge), zone 2 (surrounding zone 1 with negative charge) and zone 3 (the outer zone, representing uncharged virgin air). In the present study, we have assumed a constant electric field inside zone 1, as suggested by experimental research of corona discharges in coaxial geometry conducted by Cooray (2000). The present investigation builds upon previous studies by Tausanovic et al. (2010) and Cvetic et al. (2012) in several ways. The value of the breakdown electric field has been varied for probing its effect on channel charge distribution prior and during the return stroke. With the aim of investigating initial space charge distribution along the channel, total electric field at the outer surface of the channel corona sheath, just before the return stroke, is calculated and compared for various return stroke models. A self-consistent algorithm is applied to the generalized traveling current source return stroke model, so that the boundary condition for total electric field is fulfilled. The new density of space charge and the new radius of channel corona envelope, immediately before the return stroke stage, are calculated. The obtained results indicate a strong dependence of channel charge distribution on the breakdown electric field value. Among the compared return stroke models, transmission-line-type models have exhibited a good agreement with the predictions of the Gauss' law regarding total breakdown electric field on the corona sheath's outer surface. The generalized lightning traveling current source return stroke model gives similar results if the adjustment of the space charge density inside the corona sheath is performed.

Perspectives on marijuana use and effectiveness: A survey of NARCOMS participants.

PubMed

Cofield, Stacey S; Salter, Amber; Tyry, Tuula; Crowe, Christina; Cutter, Gary R; Fox, Robert J; Marrie, Ruth Ann

2017-08-01

Interest in and use of marijuana by persons with multiple sclerosis (MS) has increased. While potential benefits have been reported, so have concerns about potential risks. Few large studies have been conducted about the perceptions and current usage of marijuana and medical cannabinoids in persons with MS. Participants in the North American Research Committee on Multiple Sclerosis (NARCOMS) registry were surveyed in 2014 regarding legality and history of marijuana usage, both before and after diagnosis with MS. A total of 5,481 participants responded, with 78.2% female, 90% relapsing disease at onset, and a current mean age of 55.5 (10.2) years. Sixty-four percent had tried marijuana prior to their MS diagnosis, 47% have considered using for their MS, 26% have used for their MS, 20% have spoken with their physician about use, and 16% are currently using marijuana. Ninety-one percent think marijuana should be legal in some form. Men, those with higher disability, current and past nicotine smokers, and younger age were associated with a higher likelihood of current use. The majority of responders favor legalization and report high interest in the use of marijuana for treatment of MS symptoms, but may be reluctant to discuss this with health care providers. Health care providers should systematically inquire about use of marijuana.

Combined KHFAC+DC nerve block without onset or reduced nerve conductivity after block

PubMed Central

Franke, Manfred; Vrabec, Tina; Wainright, Jesse; Bhadra, Niloy; Bhadra, Narendra; Kilgore, Kevin

2017-01-01

Background Kilohertz Frequency Alternating Current waveforms (KHFAC) have been shown to provide peripheral nerve conductivity block in many acute and chronic animal models. KHFAC nerve block could be used to address multiple disorders caused by neural over-activity, including blocking pain and spasticity. However, one drawback of KHFAC block is a transient activation of nerve fibers during the initiation of the nerve block, called the onset response. The objective of this study is to evaluate the feasibility of using charge balanced direct current (CBDC) waveforms to temporarily block motor nerve conductivity distally to the KHFAC electrodes to mitigate the block onset-response. Methods A total of eight animals were used in this study. A set of four animals were used to assess feasibility and reproducibility of a combined KHFAC+CBDC block. A following randomized study, conducted on a second set of four animals, compared the onset response resulting from KHFAC alone and combined KHFAC+CBDC waveforms. To quantify the onset, peak forces and the force-time integral were measured during KHFAC block initiation. Nerve conductivity was monitored throughout the study by comparing muscle twitch forces evoked by supra-maximal stimulation proximal and distal to the block electrodes. Each animal of the randomized study received at least 300 seconds (range: 318 to 1563s) of cumulative DC to investigate the impact of combined KHFAC+CBDC on nerve viability. Results The peak onset force was reduced significantly from 20.73 N (range: 18.6–26.5 N) with KHFAC alone to 0.45 N (range: 0.2–0.7 N) with the combined CBDC and KHFAC block waveform (p<0.001). The area under the force curve was reduced from 6.8 Ns (range: 3.5–21.9 Ns) to 0.54 Ns (range: 0.18–0.86Ns) (p<0.01). No change in nerve conductivity was observed after application of the combined KHFAC+CBDC block relative to KHFAC waveforms. Conclusion The distal application of CBDC can significantly reduce or even completely prevent the KHFAC onset response without a change in nerve conductivity. PMID:25115572

Combined KHFAC + DC nerve block without onset or reduced nerve conductivity after block

NASA Astrophysics Data System (ADS)

Franke, Manfred; Vrabec, Tina; Wainright, Jesse; Bhadra, Niloy; Bhadra, Narendra; Kilgore, Kevin

2014-10-01

Objective. Kilohertz frequency alternating current (KHFAC) waveforms have been shown to provide peripheral nerve conductivity block in many acute and chronic animal models. KHFAC nerve block could be used to address multiple disorders caused by neural over-activity, including blocking pain and spasticity. However, one drawback of KHFAC block is a transient activation of nerve fibers during the initiation of the nerve block, called the onset response. The objective of this study is to evaluate the feasibility of using charge balanced direct current (CBDC) waveforms to temporarily block motor nerve conductivity distally to the KHFAC electrodes to mitigate the block onset-response. Approach. A total of eight animals were used in this study. A set of four animals were used to assess feasibility and reproducibility of a combined KHFAC + CBDC block. A following randomized study, conducted on a second set of four animals, compared the onset response resulting from KHFAC alone and combined KHFAC + CBDC waveforms. To quantify the onset, peak forces and the force-time integral were measured during KHFAC block initiation. Nerve conductivity was monitored throughout the study by comparing muscle twitch forces evoked by supra-maximal stimulation proximal and distal to the block electrodes. Each animal of the randomized study received at least 300 s (range: 318-1563 s) of cumulative dc to investigate the impact of combined KHFAC + CBDC on nerve viability. Main results. The peak onset force was reduced significantly from 20.73 N (range: 18.6-26.5 N) with KHFAC alone to 0.45 N (range: 0.2-0.7 N) with the combined CBDC and KHFAC block waveform (p < 0.001). The area under the force curve was reduced from 6.8 Ns (range: 3.5-21.9 Ns) to 0.54 Ns (range: 0.18-0.86 Ns) (p < 0.01). No change in nerve conductivity was observed after application of the combined KHFAC + CBDC block relative to KHFAC waveforms. Significance. The distal application of CBDC can significantly reduce or even completely prevent the KHFAC onset response without a change in nerve conductivity.

Analysis of recoverable current from one component of magnetic flux density in MREIT and MRCDI.

PubMed

Park, Chunjae; Lee, Byung Il; Kwon, Oh In

2007-06-07

Magnetic resonance current density imaging (MRCDI) provides a current density image by measuring the induced magnetic flux density within the subject with a magnetic resonance imaging (MRI) scanner. Magnetic resonance electrical impedance tomography (MREIT) has been focused on extracting some useful information of the current density and conductivity distribution in the subject Omega using measured B(z), one component of the magnetic flux density B. In this paper, we analyze the map Tau from current density vector field J to one component of magnetic flux density B(z) without any assumption on the conductivity. The map Tau provides an orthogonal decomposition J = J(P) + J(N) of the current J where J(N) belongs to the null space of the map Tau. We explicitly describe the projected current density J(P) from measured B(z). Based on the decomposition, we prove that B(z) data due to one injection current guarantee a unique determination of the isotropic conductivity under assumptions that the current is two-dimensional and the conductivity value on the surface is known. For a two-dimensional dominating current case, the projected current density J(P) provides a good approximation of the true current J without accumulating noise effects. Numerical simulations show that J(P) from measured B(z) is quite similar to the target J. Biological tissue phantom experiments compare J(P) with the reconstructed J via the reconstructed isotropic conductivity using the harmonic B(z) algorithm.

Current conducting end plate of fuel cell assembly

DOEpatents

Walsh, Michael M.

1999-01-01

A fuel cell assembly has a current conducting end plate with a conductive body formed integrally with isolating material. The conductive body has a first surface, a second surface opposite the first surface, and an electrical connector. The first surface has an exposed portion for conducting current between a working section of the fuel cell assembly and the electrical connector. The isolating material is positioned on at least a portion of the second surface. The conductive body can have support passage(s) extending therethrough for receiving structural member(s) of the fuel cell assembly. Isolating material can electrically isolate the conductive body from the structural member(s). The conductive body can have service passage(s) extending therethrough for servicing one or more fluids for the fuel cell assembly. Isolating material can chemically isolate the one or more fluids from the conductive body. The isolating material can also electrically isolate the conductive body from the one or more fluids.

Shared Decision-Making in Oncology - A Qualitative Analysis of Healthcare Providers' Views on Current Practice.

PubMed

Frerichs, Wiebke; Hahlweg, Pola; Müller, Evamaria; Adis, Christine; Scholl, Isabelle

2016-01-01

Despite an increased awareness of shared decision-making (SDM) and its prominent position on the health policy agenda, its implementation in routine care remains a challenge in Germany. In order to overcome this challenge, it is important to understand healthcare providers' views regarding SDM and to take their perspectives and opinions into account in the development of an implementation program. The present study aimed at exploring a) the attitudes of different healthcare providers regarding SDM in oncology and b) their experiences with treatment decisions in daily practice. A qualitative study was conducted using focus groups and individual interviews with different healthcare providers at the University Cancer Center Hamburg, Germany. Focus groups and interviews were audio-recorded, transcribed and analyzed using conventional content analysis and descriptive statistics. N = 4 focus groups with a total of N = 25 participants and N = 17 individual interviews were conducted. Attitudes regarding SDM varied greatly between the different participants, especially concerning the definition of SDM, the attitude towards the degree of patient involvement in decision-making and assumptions about when SDM should take place. Experiences on how treatment decisions are currently made varied. Negative experiences included time and structural constraints, and a lack of (multidisciplinary) communication. Positive experiences comprised informed patients, involvement of relatives and a good physician-patient relationship. The results show that German healthcare providers in oncology have a range of attitudes that currently function as barriers towards the implementation of SDM. Also, their experiences on how decision-making is currently done reveal difficulties in actively involving patients in decision-making processes. It will be crucial to take these attitudes and experiences seriously and to subsequently disentangle existing misconceptions in future implementation programs.

Novel Devices and Components for THz Systems

DTIC Science & Technology

2014-04-25

sources that have a higher THz-power-to-cost ratio than the current state of the art. Photoconductive antennas are mostly used to conduct ...a higher THz-power-to-cost ratio than the current state of the art. Photoconductive antennas are mostly used to conduct spectroscopy measurements...when incoming photons switch the semiconductor to a conducting state current can flow through the antenna

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.

A Survey of Speech-Language-Hearing Therapists' Career Situation and Challenges in Mainland China.

PubMed

Lin, Qiang; Lu, Jianliang; Chen, Zhuoming; Yan, Jiajian; Wang, Hong; Ouyang, Hui; Mou, Zhiwei; Huang, Dongfeng; O'Young, Bryan

2016-01-01

The aim of this survey was to investigate the background of speech-language pathologists and their training needs to provide a profile of the current state of the profession in Mainland China. A survey was conducted of 293 speech-language therapists. The questionnaire used asked questions related to their career background and had a 24-item ranking scale covering almost all of the common speech-language-hearing disorders. A summary of the raw data was constructed by calculating the average ranking score for each answer choice in order to determine the academic training needs with the highest preference among the respondents. The majority of respondents were female, <35 years old and with a total service time of <5 years. More than three quarters of the training needs with the highest preference among the 24 items involved basic-level knowledge of common speech-language-hearing disorders, such as diagnosis, assessment and conventional treatment, but seldom specific advanced technology or current progress. The results revealed that speech-language therapists in Mainland China tend to be young, with little total working experience and at the first stage of their career. This may be due to the lack of systematic educational programs and national certification systems for speech-language therapists. © 2016 S. Karger AG, Basel.

Marijuana use and mortality.

PubMed Central

Sidney, S; Beck, J E; Tekawa, I S; Quesenberry, C P; Friedman, G D

1997-01-01

OBJECTIVES: The purpose of this study was to examine the relationship of marijuana use to mortality. METHODS: The study population comprised 65171 Kaiser Permanente Medical Care Program enrollees, aged 15 through 49 years, who completed questionnaires about smoking habits, including marijuana use, between 1979 and 1985. Mortality follow-up was conducted through 1991. RESULTS: Compared with nonuse or experimentation (lifetime use six or fewer times), current marijuana use was not associated with a significantly increased risk of non-acquired immunodeficiency syndrome (AIDS) mortality in men (relative risk [RR] = 1.12, 95% confidence interval [CI] = 0.89, 1.39) or of total mortality in women (RR = 1.09, 95% CI = 0.80, 1.48). Current marijuana use was associated with increased risk of AIDS mortality in men (RR = 1.90, 95% CI = 1.33, 2.73), an association that probably was not causal but most likely represented uncontrolled confounding by male homosexual behavior. This interpretation was supported by the lack of association of marijuana use with AIDS mortality in men from a Kaiser Permanente AIDS database. Relative risks for ever use of marijuana were similar. CONCLUSIONS: Marijuana use in a prepaid health care-based study cohort had little effect on non-AIDS mortality in men and on total mortality in women. PMID:9146436

Treatment of oily bilge water by electrocoagulation process using aluminum electrodes

NASA Astrophysics Data System (ADS)

Soeprijanto, Perdani, Adela Dea; Nury, Dennis Farina; Pudjiastuti, Lily

2017-05-01

Electrocoagulation is electrochemical water and wastewater treatment technology which is the simplest technology using an electrochemical cell where the supply of DC power is applied to the electrodes, made of aluminum metals, and the electrolyte is oily bilge water. The electrocoagulation of oily bilge water was experimentally conducted in a batch system. Aluminum plates with dimensions of 20 cm ×8 cm × 0.2 cm were used for electrodes and mounted vertically with a distance of 4 cm. These electrodes were then connected to the direct current power supply of 10 V and 10 A. The total area of the effective working plate was 160 cm2 when immersed at a depth of 10 cm to the solutions. The results showed that total dissolved Solids (TDS) decreased from 31.2 to 7.54 mg/l and formation of sludge increased up to 12.54 g/l with oil concentration of 50 g/l for 15 min. The largest oil removal of 99.5% was obtained using the initial oil concentration of 55 g/l and the lowest of 96.25% was obtained with the initial oil concentration of 146.04 g/l. A current density of 62.3 mA/cm2 was achieved for a maximum oil removal.

Some psychometric properties of the Pediatric Quality of Life Inventory™ Version 4.0 Generic Core Scales (PedsQL™) in the general Serbian population.

PubMed

Stevanović, Dejan; Lakić, Aneta; Damnjanović, Maja

2011-08-01

The aim of this study was to evaluate the general measurement properties of the Serbian version of the Pediatric Quality of Life Inventory™ Version 4.0 Generic Core Scales (PedsQL™) self-report versions for children and adolescents (8-18 years). The PedsQL™ was completed by 238 children and adolescents. The version was descriptively analyzed first. Afterward, internal consistency and construct and convergent validity were analyzed using the classic test theory psychometrical procedures. The PedsQL™ scale score means ranged 70.65-88.34, with the total score was 80.74. Scale internal consistency reliability determined by Cronbach's coefficient was above 0.7 for all except the School, 0.65, and Emotional Functioning Scale, 0.69. The statistics assessing the adequacy of the model in confirmatory factor analysis revealed poor model fit for the current structure of the PedsQL™. Finally, the PedsQL™ total and psychosocial health showed convincing negative correlations with emotional and conduct problems, hyperactivity/inattention, and peer relationship problems. The Serbian PedsQL™ scales have appropriate internal consistency reliability, sufficient for group evaluations, and good convergent validity against psychological constructs. However, there are problems regarding its current construct validity (factorial validity).

Monitoring subterraneous water regime at the new Ain Shams university campus in Al-Obour city (northeast of Cairo-Egypt) using both azimuthal very low frequency-electromagnetic and DC-resistivity sounding techniques

NASA Astrophysics Data System (ADS)

Farag, Karam S. I.; Abd El-Aal, Mohamed H.; Garamoon, Hassan K. F.

2018-07-01

A joint azimuthal very low frequency-electromagnetic (VLF-EM) and DC-resistivity sounding survey was conducted at the new Ain Shams university campus in Al-Obour city, northwest of Cairo, Egypt. The main objective of the survey was to highlight the applicability and reliability of such non-invasive surface techniques in mapping and monitoring both the vertical and lateral electrical conductivity structures of waterlogged areas, by subterraneous water accumulations, at the campus site. Consequently, a total of 743 azimuthal VLF-EM and 4 DC-resistivity soundings were carried out in June, 2011, 2012 and 2013. The data were interpreted extensively and consistently in terms of two-dimensional (2D) transformed EM equivalent current-density and stitched inverted electrical resistivity models, without using any geological a-priori information. They could be used effectively to image the local anomalous lower electrical resistivity (higher EM equivalent current-density) structures and their near-surface spreading with time, due to the excessive accumulations of subterraneous water at the campus site. The study demonstrated that a regional azimuthal VLF-EM and DC-resistivity sounding survey could help design an optimal dewatering program for the whole city, at greatly reduced execution time.

The effective resistance between twisted superconducting filaments in tapes

NASA Astrophysics Data System (ADS)

Takács, S.; Iwakuma, M.; Funaki, K.

2001-05-01

We consider two mechanisms, which influence the effective resistance between crossing strands on flat cables or filaments in twisted tapes. The one-layer classical Rutherford-type cable and the tapes with twisted BSCCO filaments in silver matrix are taken as analogous cases. The amount of the matrix between strands or filaments increases the effective conductance compared with the direct current paths (determined by the touching area of the filaments). The increase factor is about two and can easily be suppressed by other effects, like the contact resistance between the superconductor and the matrix. The second mechanism is due to the existence of induced voltage between any points of crossing filaments. This leads to an additional effective conductance, proportional to the square of the total number of filaments. Both effects are not very important for isotropic superconductors, but due to the strong anisotropy of critical parameters they can dominate for high temperature superconductors. The first one may partially compensate the influence of the usually weaker critical current density perpendicular to the tape. The contribution due to the second effect can explain the higher resistivity of the matrix in BSCCO tapes compared with pure silver. It seems that to obtain low AC coupling losses in BSCCO tapes, structures with small filament number are required.

NDE detectability of fatigue-type cracks in high-strength alloys: NDI reliability assessments

NASA Technical Reports Server (NTRS)

Christner, Brent K.; Long, Donald L.; Rummel, Ward D.

1988-01-01

This program was conducted to generate quantitative flaw detection capability data for the nondestructive evaluation (NDE) techniques typically practiced by aerospace contractors. Inconel 718 and Haynes 188 alloy test specimens containing fatigue flaws with a wide distribution of sizes were used to assess the flaw detection capabilities at a number of contractor and government facilities. During this program 85 inspection sequences were completed presenting a total of 20,994 fatigue cracks to 53 different inspectors. The inspection sequences completed included 78 liquid penetrant, 4 eddy current, and 3 ultrasonic evaluations. The results of the assessment inspections are presented and discussed. In generating the flaw detection capability data base, procedures for data collection, data analysis, and specimen care and maintenance were developed, demonstrated, and validated. The data collection procedures and methods that evolved during this program for the measurement of flaw detection capabilities and the effects of inspection variables on performance are discussed. The Inconel 718 and Haynes 188 test specimens that were used in conducting this program and the NDE assessment procedures that were demonstrated, provide NASA with the capability to accurately assess the flaw detection capabilities of specific inspection procedures being applied or proposed for use on current and future fracture control hardware program.

Changes in social interaction over 20 years and the effects of community resources use among community-dwelling elderly persons.

PubMed

Watanabe, Kumi; Tanaka, Emiko; Wu, Bailiang; Kobayashi, Zyunko; Mochizuki, Yukiko; Kim, Yeon; Watanabe, Taeko; Okumura, Rika; Ito, Sumio; Anme, Tokie

2017-01-01

Objectives　Recently, social isolation has been reported to be a critical problem among Japanese elderly persons. However, few studies have compared social interaction in the past and the present or investigated its predictive factors. This study aimed to clarify the transitional changes in social interaction over 20 years and explore the factors related to social interaction focusing on the use of community resources.Methods　The participants were community-dwelling elderly persons aged 65 years and over. A survey was conducted 8 times from 1994 to 2014 in the suburban area of Tobishima, Japan. The Index of Social Interaction Scale was used and each subscale and the total score were calculated. Subsequently, the 2014 scores were compared with the 1994 scores using the Wilcoxon rank sum test. Logistic regression analysis was conducted to clarify the factors related to social interaction, focusing on the association between the use of community resources (local elderly management center, health care center, health promotion facility, library) in 2011 and social interaction 3 years later. Age, gender, disease, and mobility were also entered into the model as control variables.Results　Comparing social interaction in 1994 and 2014, total scores were found to have significantly increased in all age groups. Independence scores significantly increased in the overall group and in females aged 75-84. Curiosity scores also increased in both males and females. These results show that social interaction has increased over 2 decades. In addition, the use of local elderly management and health care centers, and health promotion facilities was associated with total social interaction scores 3 years later.Conclusion　The current study clarified changes in social interaction, both comprehensively and for each of its aspects, among community-dwelling elderly adults. Increasing social isolation has been reported in recent years; however, the current study showed that social interaction, including social curiosity and independence, has increased over 20 years. The effect of preventive intervention in local elderly management centers, health care centers, and health promotion facilities may be one of the causes for this increase.

Hen genetic strain and extended cold storage influence on physical egg quality from cage-free aviary housing system.

PubMed

Jones, D R; Karcher, D M; Regmi, P; Robison, C O; Gast, R K

2018-04-02

In the United States, there is an increase in need for cage-free eggs in retail and food manufacturing sectors. Understanding the impact of cage-free systems and the corresponding management on egg quality is pertinent as the U.S. industry adapts existing housing and builds new cage-free housing structures. A study was conducted comparing 2 brown shell and 2 white shell hen strains housed in a cage-free aviary system. Each set of eggs were placed in cold storage and assessed at 0, 2, 4, 8, and 12 wk. Eggs were collected at 21, 31, 42, and 60 wk of hen age. A full profile of physical quality measurements was conducted on up to 18 intact eggs for each hen strain/egg storage/hen age combination. Egg weight increased approximately 10 g for brown shell and 14 g for white shell eggs as hens aged. Many of the properties monitored were significantly impacted by all 3 main effects (hen strain, egg storage, and hen age) resulting in 3-way interactions. A brown and a white shell strain had stronger shells (44 N; P < 0.0001) than the remaining brown and white shell strains (42 N and 39 N, respectively). The current study also determined volume of shell, total length, maximum width, and percent length at maximum width to more accurately indicate egg shape than shape index. One brown shell strain produced eggs with the most consistent shape characteristics over the hen ages monitored. White shell eggs from the cage-free aviary housing produced the highest whole-egg total solids between 31 to 60 wk of hen age, whereas brown shell eggs resulted in the most consistent level of whole-egg total solids (22-23.5%). The brown and white shell strains in the current study produce cage-free aviary eggs with distinctive physical quality attributes. The outcomes from this study can be utilized by the U.S. egg industry in planning management strategies and market placement of cage-free eggs.

Effect of water treatment additives on lime softening residual trace chemical composition--implications for disposal and reuse.

PubMed

Cheng, Weizhi; Roessler, Justin; Blaisi, Nawaf I; Townsend, Timothy G

2014-12-01

Drinking water treatment residues (WTR) offer potential benefits when recycled through land application. The current guidance in Florida, US allows for unrestricted land application of lime softening WTR; alum and ferric WTR require additional evaluation of total and leachable concentrations of select trace metals prior to land application. In some cases a mixed WTR is produced when lime softening is accompanied by the addition of a coagulant or other treatment chemical; applicability of the current guidance is unclear. The objective of this research was to characterize the total and leachable chemical content of WTR from Florida facilities that utilize multiple treatment chemicals. Lime and mixed lime WTR samples were collected from 18 water treatment facilities in Florida. Total and leachable concentrations of the WTR were measured. To assess the potential for disposal of mixed WTR as clean fill below the water table, leaching tests were conducted at multiple liquid to solid ratios and under reducing conditions. The results were compared to risk-based soil and groundwater contamination thresholds. Total metal concentrations of WTR were found to be below Florida soil contaminant thresholds with Fe found in the highest abundance at a concentration of 3600 mg/kg-dry. Aluminum was the only element that exceeded the Florida groundwater contaminant thresholds using SPLP (95% UCL = 0.23 mg/L; risk threshold = 0.2 mg/L). Tests under reducing conditions showed elevated concentrations of Fe and Mn, ranging from 1 to 3 orders of magnitude higher than SPLP leachates. Mixed lime WTR concentrations (total and leachable) were lower than the ferric and alum WTR concentrations, supporting that mixed WTR are appropriately represented as lime WTR. Testing of WTR under reducing conditions demonstrated the potential for release of certain trace metals (Fe, Al, Mn) above applicable regulatory thresholds; additional evaluation is needed to assess management options where reducing conditions may develop. Copyright © 2014 Elsevier Ltd. All rights reserved.

Performance comparison between p–i–n and p–n junction tunneling field-effect transistors

NASA Astrophysics Data System (ADS)

Yoon, Young Jun; Seo, Jae Hwa; Kang, In Man

2018-06-01

In this study, we investigated the direct-current (DC) and radio-frequency (RF) performances of p–i–n and p–n junction tunneling field-effect transistors (TFETs). Compared to the p–i–n junction TFET, the p–n junction TFET exhibited higher on-state current (I on) because the channel formation mechanism of the p–n junction TFET resulted in a narrower tunneling barrier and an expanded tunneling area. Further, the reduction of I on of the p–n junction TFET by the interface trap was smaller. Moreover, the p–n junction TFET exhibited lower gate-to-drain capacitance (C gd) because a depletion capacitance (C gd,dep) was formed by the depletion region under gate dielectric. Consequently, the p–n junction TFET achieved an improvement of cut-off frequency (f T) and intrinsic delay time (τ), which are related to the current performance and total gate capacitance (C gg). We confirmed the enhancement of device performances in terms of I on, f T, and τ by the conduction mechanism of the p–n junction TFET.

Air core poloidal magnetic field system for a toroidal plasma producing device

DOEpatents

Marcus, Frederick B.

1978-01-01

A poloidal magnetics system for a plasma producing device of toroidal configuration is provided that reduces both the total volt-seconds requirement and the magnitude of the field change at the toroidal field coils. The system utilizes an air core transformer wound between the toroidal field (TF) coils and the major axis outside the TF coils. Electric current in the primary windings of this transformer is distributed and the magnetic flux returned by air core windings wrapped outside the toroidal field coils. A shield winding that is closely coupled to the plasma carries a current equal and opposite to the plasma current. This winding provides the shielding function and in addition serves in a fashion similar to a driven conducting shell to provide the equilibrium vertical field for the plasma. The shield winding is in series with a power supply and a decoupling coil located outside the TF coil at the primary winding locations. The present invention requires much less energy than the usual air core transformer and is capable of substantially shielding the toroidal field coils from poloidal field flux.

Global Electric Circuit Diurnal Variation Derived from Storm Overflight and Satellite Optical Lightning Datasets

NASA Technical Reports Server (NTRS)

Mach, Douglas M.; Blakeslee, R. J.; Bateman, M. J.; Bailey, J. C.

2011-01-01

We have combined analyses of over 1000 high altitude aircraft observations of electrified clouds with diurnal lightning statistics from the Lightning Imaging Sensor (LIS) and Optical Transient Detector (OTD) to produce an estimate of the diurnal variation in the global electric circuit. Using basic assumptions about the mean storm currents as a function of flash rate and location, and the global electric circuit, our estimate of the current in the global electric circuit matches the Carnegie curve diurnal variation to within 4% for all but two short periods of time. The agreement with the Carnegie curve was obtained without any tuning or adjustment of the satellite or aircraft data. Mean contributions to the global electric circuit from land and ocean thunderstorms are 1.1 kA (land) and 0.7 kA (ocean). Contributions to the global electric circuit from ESCs are 0.22 kA for ocean storms and 0.04 kA for land storms. Using our analysis, the mean total conduction current for the global electric circuit is 2.0 kA.

Effects of tetraethylammonium on potassium currents in a molluscan neurons

PubMed Central

1981-01-01

The effects of tetraethylammonium (TEA) on the delayed K+ current and on the Ca2+-activated K+ current of the Aplysia pacemaker neurons R-15 and L-6 were studied. The delayed outward K+ current was measured in Ca2+-free ASW containing tetrodotoxin (TTX), using brief depolarizing clamp pulses. External TEA blocks the delayed K+ current reversibly in a dose-dependent manner. The experimental results are well fitted with a Michaelis-Menten expression, assuming a one-to-one reaction between TEA and a receptor site, with an apparent dissociation constant of 6.0 mM. The block depends on membrane voltage and is reduced at positive membrane potentials. The Ca2+-activated K+ current was measured in Ca2+- free artificial seawater (ASW) containing TTX, using internal Ca2+ ion injection to directly activate the K+ conductance. External TEA and a number of other quaternary ammonium ions block the Ca2+-activated K+ current reversibly in a dose-dependent manner. TEA is the most effective blocker, with an apparent dissociation constant, for a one-to- one reaction with a receptor site, of 0.4 mM. The block decreases with depolarization. The Ca2+-activated K+ current was also measured after intracellular iontophoretic TEA injection. Internal TEA blocks the Ca2+- activated K+ current (but the block is only apparent at positive membrane potentials), is increased by depolarization, and is irreversible. The effects of external and internal TEA can be seen in measurements of the total outward K+ current at different membrane potentials in normal ASW. PMID:6265594

Japanese Magsat Team. A: Crustal structure near Japan and its Antarctic Station. B: Electric currents and hydromagnetic waves in the ionosphere and the magnetosphere

NASA Technical Reports Server (NTRS)

Fukushima, N.; Maeda, H.; Yukutake, T.; Tanaka, M.; Oshima, S.; Ogawa, K.; Kawamura, M.; Miyzaki, Y.; Uyeda, S.; Kobayashi, K. (Principal Investigator)

1981-01-01

Efforts continue in compiling tapes which contain vector and scalar data decimated at an interval of 0.5 sec, together with time and position data. A map of the total force field anomaly around Japan was developed which shows a negative magnetic anomaly in the Okhotsk Sea. Examination of vector residuals from the MGST model shows that the total force perturbation is almost ascribable to the perturbation parallel to the main geomagnetic field and that the contribution from the perturbation transverse to the main field to the total force perturbation is negligibly small. The influences of ionospheric current with equatorial electroject and of the magnetospheric field aligned current on the dawn-dusk asymmetry of daily geomagnetic variations are being considered. The total amount of electric current flowing through the plane of the Magsat orbit loop was calculated by direct application of Maxwell's equation. Results show that the total electric current is 1 to 5 ampheres, and the current direction is either sunward or antisunward.

Timber production assessment of a plantation forest: An integrated framework with field-based inventory, multi-source remote sensing data and forest management history

NASA Astrophysics Data System (ADS)

Gao, Tian; Zhu, Jiaojun; Deng, Songqiu; Zheng, Xiao; Zhang, Jinxin; Shang, Guiduo; Huang, Liyan

2016-10-01

Timber production is the purpose for managing plantation forests, and its spatial and quantitative information is critical for advising management strategies. Previous studies have focused on growing stock volume (GSV), which represents the current potential of timber production, yet few studies have investigated historical process-harvested timber. This resulted in a gap in a synthetical ecosystem service assessment of timber production. In this paper, we established a Management Process-based Timber production (MPT) framework to integrate the current GSV and the harvested timber derived from historical logging regimes, trying to synthetically assess timber production for a historical period. In the MPT framework, age-class and current GSV determine the times of historical thinning and the corresponding harvested timber, by using a ;space-for-time; substitution. The total timber production can be estimated by the historical harvested timber in each thinning and the current GSV. To test this MPT framework, an empirical study on a larch plantation (LP) with area of 43,946 ha was conducted in North China for a period from 1962 to 2010. Field-based inventory data was integrated with ALOS PALSAR (Advanced Land-Observing Satellite Phased Array L-band Synthetic Aperture Radar) and Landsat-8 OLI (Operational Land Imager) data for estimating the age-class and current GSV of LP. The random forest model with PALSAR backscatter intensity channels and OLI bands as input predictive variables yielded an accuracy of 67.9% with a Kappa coefficient of 0.59 for age-class classification. The regression model using PALSAR data produced a root mean square error (RMSE) of 36.5 m3 ha-1. The total timber production of LP was estimated to be 7.27 × 106 m3, with 4.87 × 106 m3 in current GSV and 2.40 × 106 m3 in harvested timber through historical thinning. The historical process-harvested timber accounts to 33.0% of the total timber production, which component has been neglected in the assessments for current status of plantation forests. Synthetically considering the RMSE for predictive GSV and misclassification of age-class, the error in timber production were supposed to range from -55.2 to 56.3 m3 ha-1. The MPT framework can be used to assess timber production of other tree species at a larger spatial scale, providing crucial information for a better understanding of forest ecosystem service.

Method for measuring and controlling beam current in ion beam processing

DOEpatents

Kearney, Patrick A.; Burkhart, Scott C.

2003-04-29

A method for producing film thickness control of ion beam sputter deposition films. Great improvements in film thickness control is accomplished by keeping the total current supplied to both the beam and suppressor grids of a radio frequency (RF) in beam source constant, rather than just the current supplied to the beam grid. By controlling both currents, using this method, deposition rates are more stable, and this allows the deposition of layers with extremely well controlled thicknesses to about 0.1%. The method is carried out by calculating deposition rates based on the total of the suppressor and beam currents and maintaining the total current constant by adjusting RF power which gives more consistent values.

Microscopic Analysis of Current and Mechanical Properties of Nafion® Studied by Atomic Force Microscopy

PubMed Central

Hiesgen, Renate; Helmly, Stefan; Galm, Ines; Morawietz, Tobias; Handl, Michael; Friedrich, K. Andreas

2012-01-01

The conductivity of fuel cell membranes as well as their mechanical properties at the nanometer scale were characterized using advanced tapping mode atomic force microscopy (AFM) techniques. AFM produces high-resolution images under continuous current flow of the conductive structure at the membrane surface and provides some insight into the bulk conducting network in Nafion membranes. The correlation of conductivity with other mechanical properties, such as adhesion force, deformation and stiffness, were simultaneously measured with the current and provided an indication of subsurface phase separations and phase distribution at the surface of the membrane. The distribution of conductive pores at the surface was identified by the formation of water droplets. A comparison of nanostructure models with high-resolution current images is discussed in detail. PMID:24958429

Reconstruction of apparent orthotropic conductivity tensor image using magnetic resonance electrical impedance tomography

NASA Astrophysics Data System (ADS)

Sajib, Saurav Z. K.; Kim, Ji Eun; Jeong, Woo Chul; Kim, Hyung Joong; Kwon, Oh In; Woo, Eung Je

2015-03-01

Magnetic resonance electrical impedance tomography visualizes current density and/or conductivity distributions inside an electrically conductive object. Injecting currents into the imaging object along at least two different directions, induced magnetic flux density data can be measured using a magnetic resonance imaging scanner. Without rotating the object inside the scanner, we can measure only one component of the magnetic flux density denoted as Bz. Since the biological tissues such as skeletal muscle and brain white matter show strong anisotropic properties, the reconstruction of anisotropic conductivity tensor is indispensable for the accurate observations in the biological systems. In this paper, we propose a direct method to reconstruct an axial apparent orthotropic conductivity tensor by using multiple Bz data subject to multiple injection currents. To investigate the anisotropic conductivity properties, we first recover the internal current density from the measured Bz data. From the recovered internal current density and the curl-free condition of the electric field, we derive an over-determined matrix system for determining the internal absolute orthotropic conductivity tensor. The over-determined matrix system is designed to use a combination of two loops around each pixel. Numerical simulations and phantom experimental results demonstrate that the proposed algorithm stably determines the orthotropic conductivity tensor.

Reaction formulation for radiation and scattering from plates, corner reflectors and dielectric-coated cylinders

NASA Technical Reports Server (NTRS)

Wang, N. N.

1974-01-01

The reaction concept is employed to formulate an integral equation for radiation and scattering from plates, corner reflectors, and dielectric-coated conducting cylinders. The surface-current density on the conducting surface is expanded with subsectional bases. The dielectric layer is modeled with polarization currents radiating in free space. Maxwell's equation and the boundary conditions are employed to express the polarization-current distribution in terms of the surface-current density on the conducting surface. By enforcing reaction tests with an array of electric test sources, the moment method is employed to reduce the integral equation to a matrix equation. Inversion of the matrix equation yields the current distribution, and the scattered field is then obtained by integrating the current distribution. The theory, computer program and numerical results are presented for radiation and scattering from plates, corner reflectors, and dielectric-coated conducting cylinders.

What Are the Real Procedural Costs of Bariatric Surgery? A Systematic Literature Review of Published Cost Analyses.

PubMed

Doble, Brett; Wordsworth, Sarah; Rogers, Chris A; Welbourn, Richard; Byrne, James; Blazeby, Jane M

2017-08-01

This review aims to evaluate the current literature on the procedural costs of bariatric surgery for the treatment of severe obesity. Using a published framework for the conduct of micro-costing studies for surgical interventions, existing cost estimates from the literature are assessed for their accuracy, reliability and comprehensiveness based on their consideration of seven 'important' cost components. MEDLINE, PubMed, key journals and reference lists of included studies were searched up to January 2017. Eligible studies had to report per-case, total procedural costs for any type of bariatric surgery broken down into two or more individual cost components. A total of 998 citations were screened, of which 13 studies were included for analysis. Included studies were mainly conducted from a US hospital perspective, assessed either gastric bypass or adjustable gastric banding procedures and considered a range of different cost components. The mean total procedural costs for all included studies was US$14,389 (range, US$7423 to US$33,541). No study considered all of the recommended 'important' cost components and estimation methods were poorly reported. The accuracy, reliability and comprehensiveness of the existing cost estimates are, therefore, questionable. There is a need for a comparative cost analysis of the different approaches to bariatric surgery, with the most appropriate costing approach identified to be micro-costing methods. Such an analysis will not only be useful in estimating the relative cost-effectiveness of different surgeries but will also ensure appropriate reimbursement and budgeting by healthcare payers to ensure barriers to access this effective treatment by severely obese patients are minimised.

Interventions addressing risk factors of ischaemic heart disease in sub-Saharan Africa: a systematic review.

PubMed

Ebireri, Jennifer; Aderemi, Adewale V; Omoregbe, Nicholas; Adeloye, Davies

2016-07-05

Ischaemic heart disease (IHD) is currently ranked eighth among the leading causes of deaths in sub-Saharan Africa (sSA). Yet, effective population-wide preventive measures targeting risks in the region are still largely unavailable. We aimed to review population-wide and individual-level interventions addressing risk factors of IHD among adults in sSA. A systematic search of MEDLINE, EMBASE, Global Health and AJOL was conducted to identify studies focusing on population-wide and individual-level interventions targeting risks of IHD among adults in sSA. We conducted a detailed synthesis of basic findings of selected studies. A total of 2311 studies were identified, with only 9 studies meeting our selection criteria. 3 broad interventions were identified: dietary modifications, physical activity and community-based health promotion measures on tobacco and alcohol cessation. 3 studies reported significant reduction in blood pressure (BP), and another study reported statistically significant reduction in mean total cholesterol. Other outcome measures observed ranged from mild to no reduction in BP, blood glucose, body mass index and total cholesterol, respectively. We cannot specify with all certainty contextually feasible interventions that can be effective in modifying IHD risk factors in population groups across sSA. We recommend more research on IHD, particularly on the understanding of the burden, geared towards developing and/or strengthening preventive and treatment interventions for the disease in sSA. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Volume-dependent ATP-conductive large-conductance anion channel as a pathway for swelling-induced ATP release.

PubMed

Sabirov, R Z; Dutta, A K; Okada, Y

2001-09-01

In mouse mammary C127i cells, during whole-cell clamp, osmotic cell swelling activated an anion channel current, when the phloretin-sensitive, volume-activated outwardly rectifying Cl(-) channel was eliminated. This current exhibited time-dependent inactivation at positive and negative voltages greater than around +/-25 mV. The whole-cell current was selective for anions and sensitive to Gd(3)+. In on-cell patches, single-channel events appeared with a lag period of approximately 15 min after a hypotonic challenge. Under isotonic conditions, cell-attached patches were silent, but patch excision led to activation of currents that consisted of multiple large-conductance unitary steps. The current displayed voltage- and time-dependent inactivation similar to that of whole-cell current. Voltage-dependent activation profile was bell-shaped with the maximum open probability at -20 to 0 mV. The channel in inside-out patches had the unitary conductance of approximately 400 pS, a linear current-voltage relationship, and anion selectivity. The outward (but not inward) single-channel conductance was suppressed by extracellular ATP with an IC(50) of 12.3 mM and an electric distance (delta) of 0.47, whereas the inward (but not outward) conductance was inhibited by intracellular ATP with an IC(50) of 12.9 mM and delta of 0.40. Despite the open channel block by ATP, the channel was ATP-conductive with P(ATP)/P(Cl) of 0.09. The single-channel activity was sensitive to Gd(3)+, SITS, and NPPB, but insensitive to phloretin, niflumic acid, and glibenclamide. The same pharmacological pattern was found in swelling-induced ATP release. Thus, it is concluded that the volume- and voltage-dependent ATP-conductive large-conductance anion channel serves as a conductive pathway for the swelling-induced ATP release in C127i cells.

Evidence of lifestyle modification in the management of hypercholesterolemia.

PubMed

Mannu, G S; Zaman, M J S; Gupta, A; Rehman, H U; Myint, P K

2013-02-01

Coronary heart disease (CHD) is the leading cause of morbidity and mortality worldwide. The growth of ageing populations in developing countries with progressively urbanized lifestyles are major contributors. The key risk factors for CHD such as hypercholesterolemia, diabetes mellitus, and obesity are likely to increase in the future. These risk factors are modifiable through lifestyle. To review current literature on the potential benefit of cholesterol lowering in CHD risk reduction with a particular focus on the evidence of non-pharmacological/lifestyle management of hypercholesterolemia. Medline/PubMed systematic search was conducted using a two-tier approach limited to all recent English language papers. Primary search was conducted using key words and phrases and all abstracts were subsequently screened and relevant papers were selected. The next tier of searching was conducted by (1) reviewing the citation lists of the selected papers and (2) by using PubMed weblink for related papers. Over 3600 reports were reviewed. Target cholesterol levels set out in various guidelines could be achieved by lifestyle changes, including diet, weight reduction, and increased physical activity with the goal of reducing total cholesterol to <200 mg/dL and LDL-C<100 mg/dL. Various dietary constituents such as green tea, plant sterols, soy protein have important influences on total cholesterol. Medical intervention should be reserved for those patients who have not reached this goal after 3 months of non-pharmacological approach. CHD remains as a leading cause of death worldwide and hypercholesterolemia is an important cause of CHD. Non-pharmacological methods provide initial as well as long-term measures to address this issue.

Smoking-Cessation Interventions for Urban Hospital Patients: A Randomized Comparative Effectiveness Trial.

PubMed

Sherman, Scott E; Link, Alissa R; Rogers, Erin S; Krebs, Paul; Ladapo, Joseph A; Shelley, Donna R; Fang, Yixin; Wang, Binhuan; Grossman, Ellie

2016-10-01

Hospitalization is a unique opportunity for smoking cessation, but prior interventions have measured efficacy with narrowly defined populations. The objective of this study was to enroll smokers admitted to two "safety net" hospitals and compare the effectiveness of two post-discharge cessation interventions. A randomized comparative effectiveness trial was conducted. At two New York City public hospitals, every hospitalized patient identified as a smoker (based on admission records) was approached. Inclusion criteria were: smoked cigarettes in the past 30 days; spoke English, Spanish, or Mandarin; had a U.S. phone number; not discharged to an institution where follow-up or smoking was limited; and not pregnant/breastfeeding. Of 18,797 patients identified as current smokers between July 2011 and April 2014, a total of 3,047 (16%) were discharged before being approached, 3,273 (17%) were not current smokers, 4,026 (21%) had no U.S. phone number, 2,831 (15%) were ineligible for other reasons, and 3,983 (21%) refused participation. In total, 1,618 (9%) participants enrolled in the study. During follow-up, 69% of participants were reached at 2 months and 68% at 6 months. At discharge, participants were randomized to multisession telephone counseling from study staff (n=804) or referral to the state quitline for proactive outreach and counseling (n=814). Self-reported abstinence at 6 months was measured. Analyses were conducted in late 2015. One quarter of participants were homeless or in unstable housing, 60% had a history of substance abuse, 43% reported current hazardous drinking, and half had a psychiatric diagnosis other than substance abuse. At follow-up, the rate of abstinence (30-day point prevalence) was higher in the intensive counseling arm than the quitline arm at 2 months (29.0% vs 20.7%; relative risk=1.40; 95% CI=1.13, 1.73) and 6 months (37.4% vs 31.5%; relative risk=1.19; 95% CI=1.01, 1.40). Intensive counseling was more effective than referral to the state quitline. Long-term abstinence was excellent in both groups. Many patients were not eligible for enrollment despite minimal exclusion criteria. This study is registered at www.clinicaltrials.gov NCT01363245. Published by Elsevier Inc.

The financial impact of increasing home-based high dose haemodialysis and peritoneal dialysis.

PubMed

Liu, Frank Xiaoqing; Treharne, Catrin; Culleton, Bruce; Crowe, Lydia; Arici, Murat

2014-10-02

Evidence suggests that high dose haemodialysis (HD) may be associated with better health outcomes and even cost savings (if conducted at home) versus conventional in-centre HD (ICHD). Home-based regimens such as peritoneal dialysis (PD) are also associated with significant cost reductions and are more convenient for patients. However, the financial impact of increasing the use of high dose HD at home with an increased tariff is uncertain. A budget impact analysis was performed to investigate the financial impact of increasing the proportion of patients receiving home-based dialysis modalities from the perspective of the England National Health Service (NHS) payer. A Markov model was constructed to investigate the 5 year budget impact of increasing the proportion of dialysis patients receiving home-based dialysis, including both high dose HD at home and PD, under the current reimbursement tariff and a hypothetically increased tariff for home HD (£575/week). Five scenarios were compared with the current England dialysis modality distribution (prevalent patients, 14.1% PD, 82.0% ICHD, 3.9% conventional home HD; incident patients, 22.9% PD, 77.1% ICHD) with all increases coming from the ICHD population. Under the current tariff of £456/week, increasing the proportion of dialysis patients receiving high dose HD at home resulted in a saving of £19.6 million. Conducting high dose HD at home under a hypothetical tariff of £575/week was associated with a budget increase (£19.9 million). The costs of high dose HD at home were totally offset by increasing the usage of PD to 20-25%, generating savings of £40.0 million - £94.5 million over 5 years under the increased tariff. Conversely, having all patients treated in-centre resulted in a £172.6 million increase in dialysis costs over 5 years. This analysis shows that performing high dose HD at home could allow the UK healthcare system to capture the clinical and humanistic benefits associated with this therapy while limiting the impact on the dialysis budget. Increasing the usage of PD to 20-25%, the levels observed in 2005-2008, will totally offset the additional costs and generate further savings.

Conduction mechanism of leakage current due to the traps in ZrO2 thin film

NASA Astrophysics Data System (ADS)

Seo, Yohan; Lee, Sangyouk; An, Ilsin; Song, Chulgi; Jeong, Heejun

2009-11-01

In this work, a metal-oxide-semiconductor capacitor with zirconium oxide (ZrO2) gate dielectric was fabricated by an atomic layer deposition (ALD) technique and the leakage current characteristics under negative bias were studied. From the result of current-voltage curves there are two possible conduction mechanisms to explain the leakage current in the ZrO2 thin film. The dominant mechanism is the space charge limited conduction in the high-electric field region (1.5-5.0 MV cm-1) while the trap-assisted tunneling due to the existence of traps is prevailed in the low-electric field region (0.8-1.5 MV cm-1). Conduction caused by the trap-assisted tunneling is found from the experimental results of a weak temperature dependence of current, and the trap barrier height is obtained. The space charge limited conduction is evidenced, for different temperatures, by Child's law dependence of current density versus voltage. Child's law dependence can be explained by considering a single discrete trapping level and we can obtain the activation energy of 0.22 eV.

Do health-related labour costs weaken the competitiveness of the economy?

PubMed

Häussler, Bertram; Ecker, Thomas; Schneider, Markus

2006-12-01

At least in Germany, it is widely assumed that healthcare-related labour costs weaken the competitiveness of national industries. However, there is a lack of knowledge about the amount of employers' financial burden in Germany and in other competing countries, as well as the impact on market prices of German goods. To quantify the health-related labour costs for employers in seven countries and different industries, and identify the effects of current reforms in Germany on the financial burden of employers. We calculated the spending on health in Germany and the burden on German employers (by branch of production). We then compared the total burden with that of six other countries. A univariate analysis was then conducted to examine the connection between health-related labour costs and employment. In 2000, employers paid 41.2% of the total of 283.3 billion spent on health matters in Germany. These total costs account for 3.2% of the gross output (UK: 1.8%, Switzerland: 1.9%, Poland: 2.1%, US: 3.2%, France: 3.6%, The Netherlands: 3.7%). Health-related labour costs account for 10.6% of the total labour costs. The health-related labour costs per employee are on average 3013 (from 2752 to 4793 in healthcare and the chemical industry, respectively). In the UK and the US there are corresponding labour costs of 1836 and 4256 per employee, respectively. The current health reform (2003) would reduce the labour costs by only 0.7% after 4 years (based on 2000, with all factors remaining constant). Employment increased by 3.7% from 1995 to 2000 (textile industry: -26.8%, vehicle manufacture: +18.3%). There is no empirical connection between employment and health-related labour costs. Labour costs increased by a higher amount than the health-related labour costs. The burden on German employers is moderate when compared internationally. The current reform of the German health system is not expected to improve companies' financial situation or German competitiveness. Restrictions on the range of medical services would provide a relatively small amount of relief for employers.

Combined anaerobic-aerobic treatment of landfill leachates under mesophilic, submesophilic and psychrophilic conditions.

PubMed

Kalyuzhnyi, S; Gladchenko, M; Epov, A

2003-01-01

As a first step of treatment of landfill leachates (total COD--1,430-3,810 mg/l, total nitrogen 90-162 mg/l), a performance of laboratory UASB reactors has been investigated under mesophilic (30 degrees C), sub-mesophilic (20 degrees C) and psychrophilic (10 degrees C) conditions. Under hydraulic retention times (HRT) of around 7 h, when the average organic loading rates (OLR) were around 5 g COD/l/day, the total COD removal accounted for 81% (on the average) with the effluent concentrations close to anaerobic biodegradability limit (0.25 g COD/l) for mesophilic and sub-mesophilic regimes. The psychrophilic treatment conducted under the average HRT of 8 h and the average OLR of 4.22 g COD/l/day showed a total COD removal of 47% producing the effluents (0.75 g COD/l) more suitable for subsequent biological nitrogen removal. All three anaerobic regimes used for leachate treatment were quite efficient for elimination of heavy metals (Fe, Zn, Cu, Pb, Cd) by concomitant precipitation in the form of insoluble sulphides inside the sludge bed. The application of aerobic/anoxic biofilter as a sole polishing step for psychrophilic anaerobic effluents was acceptable for elimination of biodegradable COD and nitrogen approaching the current standards for direct discharge of treated wastewater.

Pharmacological Conversion of a Cardiac Inward Rectifier into an Outward Rectifier Potassium Channel.

PubMed

Moreno-Galindo, Eloy G; Sanchez-Chapula, Jose A; Tristani-Firouzi, Martin; Navarro-Polanco, Ricardo A

2016-09-01

Potassium (K(+)) channels are crucial for determining the shape, duration, and frequency of action-potential firing in excitable cells. Broadly speaking, K(+) channels can be classified based on whether their macroscopic current outwardly or inwardly rectifies, whereby rectification refers to a change in conductance with voltage. Outwardly rectifying K(+) channels conduct greater current at depolarized membrane potentials, whereas inward rectifier channels conduct greater current at hyperpolarized membrane potentials. Under most circumstances, outward currents through inwardly rectifying K(+) channels are reduced at more depolarized potentials. However, the acetylcholine-gated K(+) channel (KACh) conducts current that inwardly rectifies when activated by some ligands (such as acetylcholine), and yet conducts current that outwardly rectifies when activated by other ligands (for example, pilocarpine and choline). The perplexing and paradoxical behavior of KACh channels is due to the intrinsic voltage sensitivity of the receptor that activates KACh channels, the M2 muscarinic receptor (M2R). Emerging evidence reveals that the affinity of M2R for distinct ligands varies in a voltage-dependent and ligand-specific manner. These intrinsic receptor properties determine whether current conducted by KACh channels inwardly or outwardly rectifies. This review summarizes the most recent concepts regarding the intrinsic voltage sensitivity of muscarinic receptors and the consequences of this intriguing behavior on cardiac physiology and pharmacology of KACh channels. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

Inert gas clearance from tissue by co-currently and counter-currently arranged microvessels

PubMed Central

Lu, Y.; Michel, C. C.

2012-01-01

To elucidate the clearance of dissolved inert gas from tissues, we have developed numerical models of gas transport in a cylindrical block of tissue supplied by one or two capillaries. With two capillaries, attention is given to the effects of co-current and counter-current flow on tissue gas clearance. Clearance by counter-current flow is compared with clearance by a single capillary or by two co-currently arranged capillaries. Effects of the blood velocity, solubility, and diffusivity of the gas in the tissue are investigated using parameters with physiological values. It is found that under the conditions investigated, almost identical clearances are achieved by a single capillary as by a co-current pair when the total flow per tissue volume in each unit is the same (i.e., flow velocity in the single capillary is twice that in each co-current vessel). For both co-current and counter-current arrangements, approximate linear relations exist between the tissue gas clearance rate and tissue blood perfusion rate. However, the counter-current arrangement of capillaries results in less-efficient clearance of the inert gas from tissues. Furthermore, this difference in efficiency increases at higher blood flow rates. At a given blood flow, the simple conduction-capacitance model, which has been used to estimate tissue blood perfusion rate from inert gas clearance, underestimates gas clearance rates predicted by the numerical models for single vessel or for two vessels with co-current flow. This difference is accounted for in discussion, which also considers the choice of parameters and possible effects of microvascular architecture on the interpretation of tissue inert gas clearance. PMID:22604885

Effect of Localizer Radiography Projection on Organ Dose at Chest CT with Automatic Tube Current Modulation.

PubMed

Saltybaeva, Natalia; Krauss, Andreas; Alkadhi, Hatem

2017-03-01

Purpose To calculate the effect of localizer radiography projections to the total radiation dose, including both the dose from localizer radiography and that from subsequent chest computed tomography (CT) with tube current modulation (TCM). Materials and Methods An anthropomorphic phantom was scanned with 192-section CT without and with differently sized breast attachments. Chest CT with TCM was performed after one localizer radiographic examination with anteroposterior (AP) or posteroanterior (PA) projections. Dose distributions were obtained by means of Monte Carlo simulations based on acquired CT data. For Monte Carlo simulations of localizer radiography, the tube position was fixed at 0° and 180°; for chest CT, a spiral trajectory with TCM was used. The effect of tube start angles on dose distribution was investigated with Monte Carlo simulations by using TCM curves with fixed start angles (0°, 90°, and 180°). Total doses for lungs, heart, and breast were calculated as the sum of the dose from localizer radiography and CT. Image noise was defined as the standard deviation of attenuation measured in 14 circular regions of interest. The Wilcoxon signed rank test, paired t test, and Friedman analysis of variance were conducted to evaluate differences in noise, TCM curves, and organ doses, respectively. Results Organ doses from localizer radiography were lower when using a PA instead of an AP projection (P = .005). The use of a PA projection resulted in higher TCM values for chest CT (P < .001) owing to the higher attenuation (P < .001) and thus resulted in higher total organ doses for all investigated phantoms and protocols (P < .001). Noise in CT images was lower with PA localizer radiography than with AP localizer radiography (P = .03). The use of an AP projection allowed for total dose reductions of 16%, 15%, and 12% for lungs, breast, and heart, respectively. Differences in organ doses were not related to tube start angles (P = .17). Conclusion The total organ doses are higher when using PA projection localizer radiography owing to higher TCM values, whereas the organ doses from PA localizer radiography alone are lower. Thus, PA localizer radiography should be used in combination with reduced reference tube current at subsequent chest CT. © RSNA, 2016 Online supplemental material is available for this article.

Performance, Facility Pressure Effects, and Stability Characterization Tests of NASA's Hall Effect Rocket with Magnetic Shielding Thruster

NASA Technical Reports Server (NTRS)

Kamhawi, Hani; Huang, Wensheng; Haag, Thomas; Yim, John; Herman, Daniel; Williams, George; Gilland, James; Peterson, Peter; Hofer, Richard; Mikellides, Ioannis

2016-01-01

NASAs Hall Effect Rocket with Magnetic Shielding (HERMeS) 12.5 kW Technology Demonstration Unit-1 (TDU-1) Hall thruster has been the subject of extensive technology maturation in preparation for flight system development. Part of the technology maturation effort included experimental evaluation of the TDU-1 thruster with conducting and dielectric front pole cover materials in two different electrical configurations. A graphite front pole cover thruster configuration with the thruster body electrically tied to cathode and an alumina front pole cover thruster configuration with the thruster body floating were evaluated. Both configurations were also evaluated at different facility background pressure conditions to evaluate background pressure effects on thruster operation. Performance characterization tests found that higher thruster performance was attained with the graphite front pole cover configuration with the thruster electrically tied to cathode. A total thrust efficiency of 68 and a total specific impulse of 2,820 s was demonstrated at a discharge voltage of 600 V and a discharge power of 12.5 kW. Thruster stability regimes were characterized with respect to the thruster discharge current oscillations and with maps of the current-voltage-magnetic field (IVB). Analysis of TDU-1 discharge current waveforms found that lower normalized discharge current peak-to-peak and root mean square magnitudes were attained when the thruster was electrically floated with alumina front pole covers. Background pressure effects characterization tests indicated that the thruster performance and stability was mostly invariant to changes in the facility background pressure for vacuum chamber pressure below 110-5 Torr-Xe (for thruster flow rate above 8 mgs). Power spectral density analysis of the discharge current waveform showed that increasing the vacuum chamber background pressure resulted in a higher discharge current dominant frequency. Finally the IVB maps of the TDU-1 thruster taken at elevated magnetic fields indicated that the discharge current became more oscillatory with increased facility background pressure at lower thruster mass flow rates, where thruster operation at higher flow rates resulted in less change to the thrusters IVB characteristics.

[Electrophysiological study on rat conduit pulmonary artery smooth muscle cells under normoxia and acute hypoxia].

PubMed

Hu, Ying; Zou, Fei; Cai, Chun-Qing; Wu, Hang-Yu; Yun, Hai-Xia; Chen, Yun-Tian; Jin, Guo-En; Ge, Ri-Li

2006-10-25

The present study was designed to investigate the electrophysiological characteristics of rat conduit pulmonary artery smooth muscle cells (PASMCs) and the response to acute hypoxia. PASMCs of the 1st to 2nd order branches in the conduit pulmonary arteries were obtained by enzymatic isolation. The PASMCs were divided into acute hypoxia preconditioned group and normoxia group. Hypoxia solutions were achieved by bubbling with 5% CO2 plus 95% N2 for at least 30 min before cell perfusion. Potassium currents were compared between these two groups using whole-cell patch clamp technique. The total outward current of PASMCs was measured under normoxia condition when iBTX [specific blocking agent of large conductance Ca-activated K(+) (BK(Ca)) channel] and 4-AP [specific blocking agent of delayed rectifier K(+) (K(DR)) channel] were added consequently into bath solution. PASMCs were classified into three types according to their size, shape and electrophysiological characteristics. Type I cells are the smallest with spindle shape, smooth surface and discrete perinuclear bulge. Type II cells show the biggest size with banana-like appearance. Type III cells have the similar size with type I, and present intermediary shape between type I and type II. iBTX had little effect on the total outward current in type I cells, while 4-AP almost completely blocked it. Most of the total outward current in type II cells was inhibited by iBTX, and the remaining was sensitive to 4-AP. In type III cells, the total outward current was sensitive to both iBTX and 4-AP. Acute hypoxia reduced the current in all three types of cells: (1614.8+/-62.5) pA to (892.4+/-33.6) pA for type I cells (P<0.01); (438.3+/-42.8) pA to (277.5+/-44.7) pA for type II cells (P<0.01); (1 042.0+/-37.2) pA to (613.6+/-23.8) pA for type III (P<0.01), and raised the resting membrane potentials (E(m)) in all these three types of cells: (-41.6+/-1.6) mV to (-18.6+/-1.5) mV (P<0.01), (-42.3+/-3.8) mV to (-30.6+/-3.0) mV (P<0.01), (-43.3+/-1.6) mV to (-28.4+/-1.4) mV (P<0.01), for type I, II, III cells, respectively. These results suggest that acute hypoxia suppresses the potassium current and improves the E(m) in PASMCs. These effects may be involved in the modulation of constriction/relaxation of conduit artery under acute hypoxia. Different distribution of K(DR) and BK(Ca) channels in these three types of PASMCs might account for their different constriction/relaxation response to acute hypoxia.

Investigating aquifer contamination and groundwater quality in eastern Terai region of Nepal.

PubMed

Mahato, Sanjay; Mahato, Asmita; Karna, Pankaj Kumar; Balmiki, Nisha

2018-05-21

This study aims at assessing the groundwater quality of the three districts of Eastern Terai region of Nepal viz. Morang, Jhapa, Sunsari using physicochemical characteristics and statistical approach so that possible contamination of water reservoir can be understood. pH, temperature, conductivity, turbidity, color, total dissolved solids, fluorides, ammonia, nitrates, chloride, total hardness, calcium hardness, calcium, magnesium, total alkalinity, iron, manganese, arsenic have to be analyzed to know the present status of groundwater quality. Results revealed that the value of analyzed parameters were within the acceptable limits for drinking water recommended by World Health Organization except for pH, turbidity, ammonia and iron. As per Nepal Drinking Water Quality Standards, fluoride and manganese too were not complying with the permissible limit. Electrical conductivity, total dissolved solids, chloride, total hardness, calcium hardness, manganese, and total alkalinity show good positive correlation with major water quality parameters. Calcium, magnesium, total hardness, calcium hardness and total alkalinity greatly influences total dissolved solids and electrical conductivity. ANOVA, Tukey, and clustering highlight the significance of three districts. Groundwater can be considered safe, but there is always a chance of contamination through chemical wastes in the heavily industrialized area of Morang and Sunsari Industrial corridor.

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.

The Effects of Elevated Specific Conductivity on the Chronic Toxicity of Mining Influenced Streams Using Ceriodaphnia dubia

PubMed Central

Armstead, Mindy Yeager; Bitzer-Creathers, Leah; Wilson, Mandee

2016-01-01

Salinization of freshwater ecosystems as a result of human activities has markedly increased in recent years. Much attention is currently directed at evaluating the effects of increased salinity on freshwater biota. In the Central Appalachian region of the eastern United States, specific conductance from alkaline discharges associated with mountain top mining practices has been implicated in macroinvertebrate community declines in streams receiving coal mining discharges. Whole effluent toxicity testing of receiving stream water was used to test the hypothesis that mine discharges are toxic to laboratory test organisms and further, that toxicity is related to ionic concentrations as indicated by conductivity. Chronic toxicity testing using Ceriodaphnia dubia was conducted by contract laboratories at 72 sites with a total of 129 tests over a 3.5 year period. The database was evaluated to determine the ionic composition of mine effluent dominated streams and whether discharge constituents were related to toxicity in C. dubia. As expected, sulfate was found to be the dominant anion in streams receiving mining discharges with bicarbonate variable and sometimes a substantial component of the dissolved solids. Overall, the temporal variability in conductance was low at each site which would indicate fairly stable water quality conditions. Results of the toxicity tests show no relationship between conductance and survival of C. dubia in the mining influenced streams with the traditional toxicity test endpoints. However, consideration of the entire dataset revealed a significant inverse relationship between conductivity and neonate production. While conductivity explained very little of the high variability in the offspring production (r2 = 0.1304), the average numbers of offspring were consistently less than 20 neonates at the highest conductivities. PMID:27814378

A Low Salinity Mystery in a Turbidity Current Measured During the Monterey Coordinated Canyon Experiment

NASA Astrophysics Data System (ADS)

Xu, J.; Wang, Z.; Wang, C.; Li, J.; Gwiazda, R.; Paull, C. K.; Maier, K. L.

2016-12-01

Conductivity-Temperature (CT) sensors are one of the most common instruments in oceanographic research that record water conductivity and temperature, two most important parameters of ocean waters from which salinity is computed. When used in super-high turbid water or flows (e.g. turbidity currents or slurries), however, the working principle of CT sensors suggests possibility of bias in conductivity measurements. In this study, a series of lab experiments were conducted to investigate how the presence of high-concentrated sediment particles influences the conductivity readings from an inductive CT sensor. The results provided evidence to challenge a long-held notion that the reduced conductivity often seen inside turbidity currents is an indication of fresh water presence.

Atmospheric Electricity and Tethered Aerostats, Volume 2

DTIC Science & Technology

1976-05-11

vs Altitude (Non- conducting or Conducting Tethers...Effect of Corona Charge Plume 15 3.1 Tether Current vs Balloon Altitude , BJ+3 - 25 Sep 73 20 3.2 Tether Current vs Balloon Altitude , Baldy - 17 Oct 73 21...3.3 Tether Current vs Balloon Altitude , Baldy - 31 Oct 73 22 3.4 Tether Current vs Balloon Altitude , Baldy - 2 Nov 73 23 3.5 Tether Current vs

Possibility of Ionospheric Cause of FACs and Convection Field in the Magnetosphere-Ionosphere System: The Harang Reversal, Premidnight Upward-FAC, and the Ionospheric Hall Polarization Field

NASA Astrophysics Data System (ADS)

Nakamizo, A.; Yoshikawa, A.

2016-12-01

Whereas it is generally thought that Birkeland Currents (FACs) are generated in the magnetosphere and that the ionospheric convection reflects the magnetospheric convection, we present a possibility that the ionosphere drives FACs and the convection field in the M-I system. We apply this idea to the Harang Reversal (HR) for demonstration. By using an ionospheric potential solver we calculate the electrostatic field for given distributions of FACs and conductance. The result shows that a conspicuous structure resembling HR is generated even for a symmetric distribution of the R1-type FACs and that the Hall polarization field is produced at the equatorward boundary of the auroral region as the primary currents diverge/converge at the conductance gradient there, which causes the potential deformation (HR). Conventionally HR has been considered to be of the magnetospheric origin, and a ring current model actually produces the corresponding structure in the magnetosphere [e.g., Erickson et al., 1991]. Observationally the divE equivalent to HR is consistent with the premidnight upward-FAC seen in Iijima and Potemra's diagram. A recent theoretical study [Ohtani et al., 2016] proposes that HR is a required structure for the interchange stability of the magnetotail in the presence of the R1 and R2-FAC systems including a premidnight upward-FAC. Returning to our result, the important point is that HR is reproduced at the conductance edge by the ionospheric polarization field, for which the primary field originates from the R1-FACs distributed far from that region. We also suggest: (i) In a more realistic finite ΣA, the total ionospheric polarization is partly released by a FAC, which may be a part of the premidnight upward-FAC. (ii) However, existing simulation models do not allow this type of current closure, and accordingly they may enhance the HR structure in the magnetosphere. This discussion should hold generally and would promote the global M-I coupling studies to the next step.

Post-stroke care after medical rehabilitation in Germany: a systematic literature review of the current provision of stroke patients.

PubMed

Hempler, Isabelle; Woitha, Kathrin; Thielhorn, Ulrike; Farin, Erik

2018-06-19

Although Germany's acute care for stroke patients already has a good reputation, continuous follow-up care is still not widely available, a problem originating in the strict separation of inpatient and outpatient care. This gap in the German health care system does not just lead to patients' potential readmission to inpatient care and compromise the sustainability of what they have accomplished during medical rehabilitation; it also places a burden on caregivers. To illustrate the current procedures on follow-up care of stroke patients in Germany, a systematic literature search was conducted to gather all available evidence. Research articles in the English or German language were searched between 2007 and 2017. Different study designs ranging from non-experimental descriptive studies, expert reports and opinions were included and categorised by two independent researchers. Relevant data was electronically searched through international and national databases and incorporated in a summary grid to investigate research outcomes and realise a narrative synthesis. A literature search was conducted to identify all relevant information on how current follow-up care is carried out and evaluated in Germany. We identified no systematic reviews on this topic, but included a total of 18 publications of various original studies, reviews and expert opinions. Included study populations also differed in either: experts, caregivers or stroke patients, including their viewpoints on the outpatient care situation of stroke patients; to capture their need for assistance or to investigate caregivers need and use for assistance. So far there is no standardised follow-up care in Germany, but this review reveals that multidisciplinary cooperation within occupational groups in outpatient rehabilitation is a key item that can influence and improve the follow-up care of stroke patients. This review was conducted to provide a broadly based overview of the current follow-up care of stroke patients in Germany. Both the new implementation of a standardised, discharge service that supports early support, to be initiated this year and numerous approaches are promising steps into the right direction to close the follow-up gap in German health care provision.

A combined quality-control methodology in Ebro Delta (NE Spain) high frequency radar system

NASA Astrophysics Data System (ADS)

Lorente, P.; Piedracoba, S.; Soto-Navarro, J.; Alvarez-Fanjul, E.

2015-08-01

Ebro River Delta is a relevant marine protected area in the western Mediterranean. In order to promote the conservation of its ecosystem and support operational decision making in this sensitive area, a three site standard-range (13.5 MHz) CODAR SeaSonde High Frequency (HF) radar was deployed in 2013. Since there is a growing demand for reliable HF radar surface current measurements, the main goal of this work is to present a combined quality control methodology. Firstly, one year-long (2014) real-time web monitoring of nonvelocity-based diagnostic parameters is conducted in order to infer both radar site status and HF radar system performance. Signal-to-noise ratio at the monopole exhibited a consistent monthly evolution although some abrupt decreases (below 10 dB), occasionally detected in June for one of the radar sites, impacted negatively on the spatiotemporal coverage of total current vectors. It seemed to be a sporadic episode since radar site overall performance was found to be robust during 2014. Secondly, a validation of HF radar data with independent in situ observations from a moored current meter was attempted for May-October 2014. The accuracy assessment of radial and total vectors revealed a consistently high agreement. The directional accuracy of the HF radar was rated at better than 8°. The correlation coefficient and RMSE values emerged in the ranges 0.58-0.83 and 4.02-18.31 cm s-1, respectively. The analysis of the monthly averaged current maps for 2014 showed that the HF radar properly represented basic oceanographic features previously reported, namely: the predominant southwestward flow, the coastal clockwise eddy confined south of Ebro Delta mouth or the Ebro River impulsive-type freshwater discharge. Future works should include the use of verified HF radar data for the rigorous skill assessment of operational ocean circulation systems currently running in Ebro estuarine region like MyOcean IBI.

Dietary administration of the commercially available probiotics enhanced the survival, growth, and innate immune responses in Mori (Cirrhinus mrigala) in a natural earthen polyculture system.

PubMed

Ullah, Amin; Zuberi, Amina; Ahmad, Muhammad; Bashir Shah, Aqsa; Younus, Naima; Ullah, Sami; Khattak, Muhammad Nasir Khan

2018-01-01

The use of probiotics is considered effective for survival, growth and enhanced immune response in aquaculture. In the current study, effects of commercially available probiotic (Magic Plus) was investigated on survival, growth and immune response of Mori (Cirrhinus mrigala) in a polyculture system. The experiment was conducted for 90 days on 1200 fingerlings in two groups i.e. control and probiotic supplemented groups each having 600 fingerlings. Control group was fed with 35% protein basal diet without any supplements and the other group was supplemented with commercially available probiotic at the rate of (10 12  CFU kg -1 diet). After 90 days, probiotic supplemented group was characterized with significant increase (p < 0.05) in growth parameters like, total weight, total length, %weight gain, specific growth rate and survival growth rate. Immunological indices like, lysozyme activity, white blood cells, total plasma protein level and immunoglobulin (IgM) of supplemented group were also significantly (p < 0.05) enhanced. Moreover, digestive enzymes i.e. cellulase, protease and amylase were also found to be significantly (p < 0.05) hyper-active in probiotic supplemented groups. Haematological parameters like, RBCs, Hb, Hct, MCH and MCHC were also significantly (p < 0.05) increased. Thus, the current study strongly suggests that a commercially available probiotic Magic plus may serve as a healthy and immunostimulating feed additive in C. mrigala culture. Copyright © 2017 Elsevier Ltd. All rights reserved.

Toward Developing a New Occupational Exposure Metric Approach for Characterization of Diesel Aerosols

PubMed Central

Cauda, Emanuele G.; Ku, Bon Ki; Miller, Arthur L.; Barone, Teresa L.

2015-01-01

The extensive use of diesel-powered equipment in mines makes the exposure to diesel aerosols a serious occupational issue. The exposure metric currently used in U.S. underground noncoal mines is based on the measurement of total carbon (TC) and elemental carbon (EC) mass concentration in the air. Recent toxicological evidence suggests that the measurement of mass concentration is not sufficient to correlate ultrafine aerosol exposure with health effects. This urges the evaluation of alternative measurements. In this study, the current exposure metric and two additional metrics, the surface area and the total number concentration, were evaluated by conducting simultaneous measurements of diesel ultrafine aerosols in a laboratory setting. The results showed that the surface area and total number concentration of the particles per unit of mass varied substantially with the engine operating condition. The specific surface area (SSA) and specific number concentration (SNC) normalized with TC varied two and five times, respectively. This implies that miners, whose exposure is measured only as TC, might be exposed to an unknown variable number concentration of diesel particles and commensurate particle surface area. Taken separately, mass, surface area, and number concentration did not completely characterize the aerosols. A comprehensive assessment of diesel aerosol exposure should include all of these elements, but the use of laboratory instruments in underground mines is generally impracticable. The article proposes a new approach to solve this problem. Using SSA and SNC calculated from field-type measurements, the evaluation of additional physical properties can be obtained by using the proposed approach. PMID:26361400

The effectiveness of police custody assessments in identifying suspects with intellectual disabilities and attention deficit hyperactivity disorder

PubMed Central

2013-01-01

Background Intellectual Disabilities (ID) and Attention Deficit Hyperactivity Disorder (ADHD) are recognized psychological vulnerabilities in police interviews and court proceedings in England and Wales. The aims of this study were to investigate: (a) the prevalence of ID and/or ADHD among suspects detained at a large London metropolitan police station and their relationship with conduct disorder (CD), (b) the impact of their condition on police staff resources, (c) the effectiveness of current custody assessment tools in identifying psychological vulnerabilities, and (d) the use of ‘Appropriate Adults’ in interviews. Method A total of 200 individuals in a police custody suite were interviewed and screened for ID, ADHD (current symptoms) and CD. Results The screening rates for these three disorders were 6.7%, 23.5% and 76.3%, respectively. ADHD contributed significantly to increased requests being made of staff after controlling for CD and duration of time in custody. This is a novel finding. Reading and writing difficulties and mental health problems were often identified from the custody risk assessment tools, but they were not used effectively to inform on the need for the use of an Appropriate Adult. The frequency with which Appropriate Adults were provided to support detainees in police interviews (4.2%) remains almost identical to that found in a similar study conducted 20 years previously. Conclusions The current findings suggest that in spite of reforms recently made in custodial settings, procedures may not have had the anticipated impact of improving safeguards for vulnerable suspects. Detainees with ID and ADHD require an Appropriate Adult during police interviews and other formal custody procedures, which they commonly do not currently receive. The findings of the current study suggest this may be due, in large part, to the ineffective use of risk-assessment tools and healthcare professionals, which represent missed opportunities to identify such vulnerabilities. PMID:24261542

The current total economic burden of diabetes mellitus in the Netherlands.

PubMed

Peters, M L; Huisman, E L; Schoonen, M; Wolffenbuttel, B H R

2017-09-01

Insight into the total economic burden of diabetes mellitus (DM) is essential for decision makers and payers. Currently available estimates for the Netherlands only include part of the total burden or are no longer up-to-date. Therefore, this study aimed to determine the current total economic burden of DM and its complications in the Netherlands, by including all the relevant cost components. The study combined a systematic literature review to identify all relevant published information and a targeted review to identify relevant information in the grey literature. The identified evidence was then combined to estimate the current total economic burden. In 2016, there were an estimated 1.1 million DM patients in the Netherlands, of whom approximately 10% had type 1 and 90% had type 2 DM. The estimated current total economic burden of DM was € 6.8 billion in 2016. Healthcare costs (excluding costs of complications) were € 1.6 billion, direct costs of complications were € 1.3 billion and indirect costs due to productivity losses, welfare payments and complications were € 4.0 billion. DM and its complications pose a substantial economic burden to the Netherlands, which is expected to rise due to changing demographics and lifestyle. Indirect costs, such as welfare payments, accounted for a large portion of the current total economic burden of DM, while these cost components are often not included in cost estimations. Publicly available data for key cost drivers such as complications were scarce.

Uncertainty analysis of the simulations of effects of discharging treated wastewater to the Red River of the North at Fargo, North Dakota, and Moorhead, Minnesota

USGS Publications Warehouse

Wesolowski, Edwin A.

1996-01-01

Two separate studies to simulate the effects of discharging treated wastewater to the Red River of the North at Fargo, North Dakota, and Moorhead, Minnesota, have been completed. In the first study, the Red River at Fargo Water-Quality Model was calibrated and verified for icefree conditions. In the second study, the Red River at Fargo Ice-Cover Water-Quality Model was verified for ice-cover conditions.To better understand and apply the Red River at Fargo Water-Quality Model and the Red River at Fargo Ice-Cover Water-Quality Model, the uncertainty associated with simulated constituent concentrations and property values was analyzed and quantified using the Enhanced Stream Water Quality Model-Uncertainty Analysis. The Monte Carlo simulation and first-order error analysis methods were used to analyze the uncertainty in simulated values for six constituents and properties at sites 5, 10, and 14 (upstream to downstream order). The constituents and properties analyzed for uncertainty are specific conductance, total organic nitrogen (reported as nitrogen), total ammonia (reported as nitrogen), total nitrite plus nitrate (reported as nitrogen), 5-day carbonaceous biochemical oxygen demand for ice-cover conditions and ultimate carbonaceous biochemical oxygen demand for ice-free conditions, and dissolved oxygen. Results are given in detail for both the ice-cover and ice-free conditions for specific conductance, total ammonia, and dissolved oxygen.The sensitivity and uncertainty of the simulated constituent concentrations and property values to input variables differ substantially between ice-cover and ice-free conditions. During ice-cover conditions, simulated specific-conductance values are most sensitive to the headwatersource specific-conductance values upstream of site 10 and the point-source specific-conductance values downstream of site 10. These headwater-source and point-source specific-conductance values also are the key sources of uncertainty. Simulated total ammonia concentrations are most sensitive to the point-source total ammonia concentrations at all three sites. Other input variables that contribute substantially to the variability of simulated total ammonia concentrations are the headwater-source total ammonia and the instream reaction coefficient for biological decay of total ammonia to total nitrite. Simulated dissolved-oxygen concentrations at all three sites are most sensitive to headwater-source dissolved-oxygen concentration. This input variable is the key source of variability for simulated dissolved-oxygen concentrations at sites 5 and 10. Headwatersource and point-source dissolved-oxygen concentrations are the key sources of variability for simulated dissolved-oxygen concentrations at site 14.During ice-free conditions, simulated specific-conductance values at all three sites are most sensitive to the headwater-source specific-conductance values. Headwater-source specificconductance values also are the key source of uncertainty. The input variables to which total ammonia and dissolved oxygen are most sensitive vary from site to site and may or may not correspond to the input variables that contribute the most to the variability. The input variables that contribute the most to the variability of simulated total ammonia concentrations are pointsource total ammonia, instream reaction coefficient for biological decay of total ammonia to total nitrite, and Manning's roughness coefficient. The input variables that contribute the most to the variability of simulated dissolved-oxygen concentrations are reaeration rate, sediment oxygen demand rate, and headwater-source algae as chlorophyll a.

Age and choice in health insurance: evidence from a discrete choice experiment.

PubMed

Becker, Karolin; Zweifel, Peter

2008-01-01

A uniform package of benefits and uniform cost sharing are elements of regulation inherent in most social health insurance systems. Both elements risk burdening the population with a welfare loss if preferences for risk and insurance attributes differ. This suggests the introduction of more choice in social health insurance packages may be advantageous; however, it is widely believed that this would not benefit the elderly.A representative telephone survey of 1000 people aged >24 years living in the German- and French-speaking parts of Switzerland was conducted. Participants were asked to compare the status quo (i.e. their current insurance contract) with ten hypothetical alternatives. In addition, participants were asked questions concerning utilization of healthcare services; overall satisfaction with the healthcare system, insurer and insurance policy; and a general preference for new elements in the insurance package. Socioeconomic variables surveyed were age, sex, total household income, education (seven categories ranging from primary school to university degree), place of residence, occupation, and marital status. To examine the relationship between age and willingness to pay (WTP) for additional options in Swiss social health insurance.A representative telephone survey of 1000 people aged >24 years living in the German- and French-speaking parts of Switzerland was conducted. Participants were asked to compare the status quo (i.e. their current insurance contract) with ten hypothetical alternatives. In addition, participants were asked questions concerning utilization of healthcare services; overall satisfaction with the healthcare system, insurer and insurance policy; and a general preference for new elements in the insurance package. Socioeconomic variables surveyed were age, sex, total household income, education (seven categories ranging from primary school to university degree), place of residence, occupation, and marital status. A discrete choice experiment was developed using six attributes (deductibles, co-payment, access to alternative medicines, medication choice, access to innovation, and monthly premium) that are currently in debate within the context of Swiss health insurance. These attributes have been shown to be important in the choice of insurance contract. Using statistical design optimization procedures, the number of choice sets was reduced to 27 and randomly split into three groups. One choice was included twice to test for consistency. Two random effects probit models were developed: a simple model where marginal utilities and WTP values were not allowed to vary according to socioeconomic characteristics, and a more complex model where the values were permitted to depend on socioeconomic variables.A representative telephone survey of 1000 people aged >24 years living in the German- and French-speaking parts of Switzerland was conducted. Participants were asked to compare the status quo (i.e. their current insurance contract) with ten hypothetical alternatives. In addition, participants were asked questions concerning utilization of healthcare services; overall satisfaction with the healthcare system, insurer and insurance policy; and a general preference for new elements in the insurance package. Socioeconomic variables surveyed were age, sex, total household income, education (seven categories ranging from primary school to university degree), place of residence, occupation, and marital status. All chosen elements proved relevant for choice in the simple model. Accounting for socioeconomic characteristics in the comprehensive model reveals preference heterogeneity for contract attributes, but also for the propensity to consider deviating from the status quo and choosing an alternative health insurance contract. The findings suggest that while the elderly do exhibit a stronger status quo bias than younger age groups, they require less rather than more specific compensation for selected cutbacks, indicating a potential for contracts that induce self-rationing in return for lower premiums.

In-line beam current monitor

DOEpatents

Ekdahl, Jr., Carl A.; Frost, Charles A.

1986-01-01

An intense relativistic electron beam current monitor for a gas neutralized beam transport line includes a first foil for conducting plasma current to the wall where it is measured as it traverses an inductive loop formed by a cavity in the wall. An insulator foil separates the first foil from a second conducting foil which returns the current to the plasma environment.

In-line beam current monitor

DOEpatents

Ekdahl, C.A. Jr.; Frost, C.A.

1984-11-13

An intense relativistic electron beam current monitor for a gas neutralized beam transport line includes a first foil for conducting plasma current to the wall where it is measured as it traverses an inductive loop formed by a cavity in the wall. An insulator foil separates the first foil from a second conducting foil which returns the current to the plasma environment.

A uniquely adaptable pore is consistent with NALCN being an ion sensor

PubMed Central

Senatore, Adriano; Spafford, J. David

2013-01-01

NALCN is an intriguing, orphan ion channel among the 4x6TM family of related voltage-gated cation channels, sharing a common architecture of four homologous domains consisting of six transmembrane helices, separated by three cytoplasmic linkers and delimited by N and C-terminal ends. NALCN is one of the shortest 4x6TM family members, lacking much of the variation that provides the diverse palate of gating features, and tissue specific adaptations of sodium and calcium channels. NALCN’s most distinctive feature is that that it possesses a highly adaptable pore with a calcium-like EEEE selectivity filter in radially symmetrical animals and a more sodium-like EEKE or EKEE selectivity filter in bilaterally symmetrical animals including vertebrates. Two lineages of animals evolved alternative calcium-like EEEE and sodium-like EEKE / EKEE pores, spliced to regulate NALCN functions in differing cellular environments, such as muscle (heart and skeletal) and secretory tissue (brain and glands), respectively. A highly adaptable pore in an otherwise conserved ion channel in the 4x6TM channel family is not consistent with a role for NALCN in directly gating a significant ion conductance that can be either sodium ions or calcium ions. NALCN was proposed to be an expressible Gd3+-sensitive, NMDG+-impermeant, non-selective and ohmic leak conductance in HEK-293T cells, but we were unable to distinguish these reported currents from leaky patch currents (ILP) in control HEK-293T cells. We suggest that NALCN functions as a sensor for the much larger UNC80/UNC79 complex, in a manner consistent with the coupling mechanism known for other weakly or non-conducting 4x6TM channel sensor proteins such as Nax or Cav1.1. We propose that NALCN serves as a variable sensor that responds to calcium or sodium ion flux, depending on whether the total cellular current density is generated more from calcium-selective or sodium-selective channels. PMID:23442378

A uniquely adaptable pore is consistent with NALCN being an ion sensor.

PubMed

Senatore, Adriano; Spafford, J David

2013-01-01

NALCN is an intriguing, orphan ion channel among the 4x6TM family of related voltage-gated cation channels, sharing a common architecture of four homologous domains consisting of six transmembrane helices, separated by three cytoplasmic linkers and delimited by N and C-terminal ends. NALCN is one of the shortest 4x6TM family members, lacking much of the variation that provides the diverse palate of gating features, and tissue specific adaptations of sodium and calcium channels. NALCN's most distinctive feature is that that it possesses a highly adaptable pore with a calcium-like EEEE selectivity filter in radially symmetrical animals and a more sodium-like EEKE or EKEE selectivity filter in bilaterally symmetrical animals including vertebrates. Two lineages of animals evolved alternative calcium-like EEEE and sodium-like EEKE / EKEE pores, spliced to regulate NALCN functions in differing cellular environments, such as muscle (heart and skeletal) and secretory tissue (brain and glands), respectively. A highly adaptable pore in an otherwise conserved ion channel in the 4x6TM channel family is not consistent with a role for NALCN in directly gating a significant ion conductance that can be either sodium ions or calcium ions. NALCN was proposed to be an expressible Gd ( 3+) -sensitive, NMDG (+) -impermeant, non-selective and ohmic leak conductance in HEK-293T cells, but we were unable to distinguish these reported currents from leaky patch currents (ILP) in control HEK-293T cells. We suggest that NALCN functions as a sensor for the much larger UNC80/UNC79 complex, in a manner consistent with the coupling mechanism known for other weakly or non-conducting 4x6TM channel sensor proteins such as Nax or Cav 1.1. We propose that NALCN serves as a variable sensor that responds to calcium or sodium ion flux, depending on whether the total cellular current density is generated more from calcium-selective or sodium-selective channels.

Cross-cultural adaptation and validation of the Behcet's Disease Current Activity Form in Korea.

PubMed

Choi, Hyo Jin; Seo, Mi Ryoung; Ryu, Hee Jung; Baek, Han Joo

2015-09-01

This study was undertaken to perform a cross-cultural adaptation of the Behcet's Disease Current Activity Form (BDCAF, version 2006) questionnaire to the Korean language and to evaluate its reliability and validity in a population of Korean patients with Behcet's disease (BD). A cross-cultural study was conducted among patients with BD who attended our rheumatology clinic between November 2012 and March 2013. There were 11 males and 35 females in the group. The mean age of the participants was 48.5 years and the mean disease duration was 6.4 years. The first BDCAF questionnaire was completed on arrival and the second assessment was performed 20 minutes later by a different physician. The test-retest reliability was analyzed by computing κ statistics. Kappa scores of > 0.6 indicated a good agreement. To assess the validity, we compared the total BDCAF score with the patient's/clinician's perception of disease activity and the Korean version of the Behcet's Disease Quality of Life (BDQOL). For the test-retest reliability, good agreements were achieved on items such as headache, oral/genital ulceration, erythema, skin pustules, arthralgia, nausea/vomiting/abdominal pain, and diarrhea with altered/frank blood per rectum. Moderate agreement was observed for eye and nervous system involvement. We achieved a fair agreement for arthritis and major vessel involvement. Significant correlations were obtained between the total BDCAF score with the BDQOL and the patient's/clinician's perception of disease activity p < 0.05). The Korean version of the BDCAF is a reliable and valid instrument for measuring current disease activity in Korean BD patients.

The Influence of Current Density and Magnetic Field Topography in Optimizing the Performance, Divergence, and Plasma Oscillations of High Specific Impulse Hall Thrusters

NASA Technical Reports Server (NTRS)

Hofer, Richard R.; Jankovsky, Robert S.

2003-01-01

Recent studies of xenon Hall thrusters have shown peak efficiencies at specific impulses of less than 3000 s. This was a consequence of modern Hall thruster magnetic field topographies, which have been optimized for 300 V discharges. On-going research at the NASA Glenn Research Center is investigating this behavior and methods to enhance thruster performance. To conduct these studies, a laboratory model Hall thruster that uses a pair of trim coils to tailor the magnetic field topography for high specific impulse operation has been developed. The thruster-the NASA-173Mv2 was tested to determine how current density and magnetic field topography affect performance, divergence, and plasma oscillations at voltages up to 1000 V. Test results showed there was a minimum current density and optimum magnetic field topography at which efficiency monotonically increased with voltage. At 1000 V, 10 milligrams per second the total specific impulse was 3390 s and the total efficiency was 60.8%. Plume divergence decreased at 400-1000 V, but increased at 300-400 V as the result of plasma oscillations. The dominant oscillation frequency steadily increased with voltage, from 14.5 kHz at 300 V, to 22 kHz at 1000 V. An additional oscillatory mode in the 80-90 kHz frequency range began to appear above 500 V. The use of trim coils to modify the magnetic field improved performance while decreasing plume divergence and the frequency and magnitude of plasma oscillations.

L-type calcium channels refine the neural population code of sound level

PubMed Central

Grimsley, Calum Alex; Green, David Brian

2016-01-01

The coding of sound level by ensembles of neurons improves the accuracy with which listeners identify how loud a sound is. In the auditory system, the rate at which neurons fire in response to changes in sound level is shaped by local networks. Voltage-gated conductances alter local output by regulating neuronal firing, but their role in modulating responses to sound level is unclear. We tested the effects of L-type calcium channels (CaL: CaV1.1–1.4) on sound-level coding in the central nucleus of the inferior colliculus (ICC) in the auditory midbrain. We characterized the contribution of CaL to the total calcium current in brain slices and then examined its effects on rate-level functions (RLFs) in vivo using single-unit recordings in awake mice. CaL is a high-threshold current and comprises ∼50% of the total calcium current in ICC neurons. In vivo, CaL activates at sound levels that evoke high firing rates. In RLFs that increase monotonically with sound level, CaL boosts spike rates at high sound levels and increases the maximum firing rate achieved. In different populations of RLFs that change nonmonotonically with sound level, CaL either suppresses or enhances firing at sound levels that evoke maximum firing. CaL multiplies the gain of monotonic RLFs with dynamic range and divides the gain of nonmonotonic RLFs with the width of the RLF. These results suggest that a single broad class of calcium channels activates enhancing and suppressing local circuits to regulate the sensitivity of neuronal populations to sound level. PMID:27605536

Supply of human allograft tissue in Canada.

PubMed

Lakey, Jonathan R T; Mirbolooki, Mohammadreza; Rogers, Christina; Mohr, Jim

2007-01-01

There is relatively little known about the supply for allograft tissues in Canada. The major aim of this study is to quantify the current or "Known Supply" of human allograft tissue (bone, tendons, soft tissue, cardiovascular, ocular and skin) from known tissue banks in Canada, to estimate the "Unknown Supply" of human allograft tissue available to Canadian users from other sources, and to investigate the nature and source of these tissue products. Two surveys were developed; one for tissue banks processing one or more tissue types and the other specific to eye banks. Thirty nine sites were initially identified as potential tissue bank respondent sites. Of the 39 sites, 29 sites indicated that they were interested in participating or would consider completing the survey. A survey package and a self-addressed courier envelope were couriered to each of 29 sites. A three week response time was indicated. The project consultants conducted telephone and email follow-up for incomplete data. Unknown supply was estimated by 5 methods. Twenty-eight of 29 sites (97%) completed and returned surveys. Over the past year, respondents reported a total of 5,691 donors (1,550 living and 4,141 cadaveric donors). Including cancellous ground bone, there were 10,729 tissue products produced by the respondent banks. Of these, 71% were produced by accredited banks and 32% were ocular tissues. Total predicted shortfall of allograft tissues was 31,860-66,481 grafts. Through estimating Current supply, and compiling additional qualitative information, this study has provided a snapshot of the current Canadian supply and shortfall of allograft tissue grafts.

Two modes of polyamine block regulating the cardiac inward rectifier K+ current IK1 as revealed by a study of the Kir2.1 channel expressed in a human cell line.

PubMed

Ishihara, Keiko; Ehara, Tsuguhisa

2004-04-01

The strong inward rectifier K(+) current, I(K1), shows significant outward current amplitude in the voltage range near the reversal potential and thereby causes rapid repolarization at the final phase of cardiac action potentials. However, the mechanism that generates the outward I(K1) is not well understood. We recorded currents from the inside-out patches of HEK 293T cells that express the strong inward rectifier K(+) channel Kir2.1 and studied the blockage of the currents caused by cytoplasmic polyamines, namely, spermine and spermidine. The outward current-voltage (I-V) relationships of Kir2.1, obtained with 5-10 microm spermine or 10-100 microm spermidine, were similar to the steady-state outward I-V relationship of I(K1), showing a peak at a level that is approximately 20 mV more positive than the reversal potential, with a negative slope at more positive voltages. The relationships exhibited a plateau or a double-hump shape with 1 microm spermine/spermidine or 0.1 microm spermine, respectively. In the chord conductance-voltage relationships, there were extra conductances in the positive voltage range, which could not be described by the Boltzmann relations fitting the major part of the relationships. The extra conductances, which generated most of the outward currents in the presence of 5-10 microm spermine or 10-100 microm spermidine, were quantitatively explained by a model that considered two populations of Kir2.1 channels, which were blocked by polyamines in either a high-affinity mode (Mode 1 channel) or a low-affinity mode (Mode 2 channel). Analysis of the inward tail currents following test pulses indicated that the relief from the spermine block of Kir2.1 consisted of an exponential component and a virtually instantaneous component. The fractions of the two components nearly agreed with the fractions of the blockages in Mode 1 and Mode 2 calculated by the model. The estimated proportion of Mode 1 channels to total channels was 0.9 with 0.1-10 microm spermine, 0.75 with 1-100 microm spermidine, and between 0.75 and 0.9 when spermine and spermidine coexisted. An interaction of spermine/spermidine with the channel at an intracellular site appeared to modify the equilibrium of the two conformational channel states that allow different modes of blockage. Our results suggest that the outward I(K1) is primarily generated by channels with lower affinities for polyamines. Polyamines may regulate the amplitude of the outward I(K1), not only by blocking the channels but also by modifying the proportion of channels that show different sensitivities to the polyamine block.

The transport systems of Ventricaria ventricosa: hypotonic and hypertonic turgor regulation.

PubMed

Bisson, M A; Beilby, M J

2002-11-01

The time course of hypertonic and hypotonic turgor regulation was studied in Ventricaria (Valonia) using pressure probe and I/V(current-voltage) analysis. Of 11 cells, 9 exhibited hypertonic turgor regulation, ranging from 100% regulation in 150 min to 14% regulation (14% recovery of the decrease in turgor) in 314 min. Some cells began regulating immediately, others took up to 90 min to begin. The resting PD (potential difference) became more positive in most cells. The I/V characteristics became more nonlinear with high resistance between -150 and -20 mV and negative conductance region near -70 mV. Prolonged (16 sec) voltage clamps to negative levels (-100 to -150 mV) showed progressively more rapid current turn-off, but subsequent I/V characteristics were not affected. Clamping to +150 mV, however, abolished the high conductance between -50 and +100 mV to yield a uniform high resistance I/V characteristic, similar to that in high [K+]o. Decreasing illumination from 2.02 micromol sec(-1) m(-2) to 0.5 micromol sec(-1)1 m(-2) had a similar effect. Two out of a total of three cells exhibited hypotonic turgor regulation. Both cells started regulating within minutes and achieved near 50% regulation within 50 min. The PD became more negative. The I/V curves exhibited high resistance between +50 and +150 mV. The characteristics were similar to those in cells exposed to low [K+]o. Prolonged voltage clamps to both negative and positive levels showed slow current increase. Decreased illumination increased the membrane resistance.

Performance Evaluation of Individual Aircraft Based Advisory Concept for Surface Management

NASA Technical Reports Server (NTRS)

Gupta, Gautam; Malik, Waqar; Tobias, Leonard; Jung, Yoon; Hong, Ty; Hayashi, Miwa

2013-01-01

Surface operations at airports in the US are based on tactical operations, where departure aircraft primarily queue up and wait at the departure runways. NASA's Spot And Runway Departure Advisor (SARDA) tool was developed to address these inefficiencies through Air Traffic Control Tower advisories. The SARDA system is being updated to include collaborative gate hold, either tactically or strategically. This paper presents the results of the human-in-the-loop evaluation of the tactical gate hold version of SARDA in a 360 degree simulated tower setting. The simulations were conducted for the east side of the Dallas/Fort Worth airport. The new system provides gate hold, ground controller and local controller advisories based on a single scheduler. Simulations were conducted with SARDA on and off, the off case reflecting current day operations with no gate hold. Scenarios based on medium (1.2x current levels) and heavy (1.5x current levels) traffic were explored. Data collected from the simulation was analyzed for runway usage, delay for departures and arrivals, and fuel consumption. Further, Traffic Management Initiatives were introduced for a subset of the aircraft. Results indicated that runway usage did not change with the use of SARDA, i.e., there was no loss in runway throughput as compared to baseline. Taxiing delay was significantly reduced with the use of advisory by 45% in medium scenarios and 60% in heavy. Arrival delay was unaffected by the use of advisory. Total fuel consumption was also reduced by 23% in medium traffic and 33% in heavy. TMI compliance appeared unaffected by the advisory

Electrical properties of the 8-12th September, 2015 massive dust outbreak over the Levant

NASA Astrophysics Data System (ADS)

Katz, Shai; Yair, Yoav; Price, Colin; Yaniv, Roy; Silber, Israel; Lynn, Barry; Ziv, Baruch

2018-03-01

We report new electrical measurements conducted during the massive dust outbreak that occurred over the Levant in September 08-12, 2015. That event was one of the strongest dust storms on record and engulfed the entire region for 5 consecutive days, over Iraq through Syria, Jordan, Israel, Lebanon, Cyprus and Egypt. At its peak, Aerosol Optical Thickness of 4.0 was measured in southern Israel. Ground-based measurements of the electrical field (Ez) and current density (J) were conducted at the Wise Observatory (WO) in Mizpe-Ramon (30°35‧N, 34°45‧E) and near the top of Mt. Hermon (30°24‧N, 35°51‧E). During the dust outbreak very large fluctuations in the electrical parameters were measured at both stations, with remarkable differences between the two locations. While at the Mt. Hermon station we registered positive values of the electric field and total current density, the values registered at the Wise Observatory were significantly smaller and more negative. The Mt. Hermon site showed Ez and J values fluctuating between - 460 and + 570 V m- 1 and - 14.5 and + 18 pA m- 2 respectively. In contrast, the Ez values registered at WO varied between - 430 and + 10 V m- 1, and the current density fluctuated between - 6 and + 3 pA m- 2. We show that the unique generation and evolution of this dust outbreak gave rise to a significantly different charge structure compared with that observed in short lived convective events, and suggest a tentative explanation for the obtained results.

Performance Evaluation of SARDA: An Individual Aircraft-Based Advisory Concept for Surface Management

NASA Technical Reports Server (NTRS)

Jung, Yoon; Malik, Waqar; Tobias, Leonard; Gupta, Gautam; Hoang, Ty; Hayashi, Miwa

2015-01-01

Surface operations at airports in the US are based on tactical operations, where departure aircraft primarily queue up and wait at the departure runways. NASAs Spot And Runway Departure Advisor (SARDA) tool was developed to address these inefficiencies through Air Traffic Control Tower advisories. The SARDA system is being updated to include collaborative gate hold, either tactically or strategically. This paper presents the results of the human-in-the-loop evaluation of the tactical gate hold version of SARDA in a 360 degree simulated tower setting. The simulations were conducted for the east side of the Dallas-Fort Worth airport. The new system provides gate hold, ground controller and local controller advisories based on a single scheduler. Simulations were conducted with SARDA on and off, the off case reflecting current day operations with no gate hold. Scenarios based on medium (1.2x current levels) and heavy (1.5x current levels) traffic were explored. Data collected from the simulation was analyzed for runway usage, delay for departures and arrivals, and fuel consumption. Further, Traffic Management Initiatives were introduced for a subset of the aircraft. Results indicated that runway usage did not change with the use of SARDA, i.e., there was no loss in runway throughput as compared to baseline. Taxiing delay was significantly reduced with the use of advisory by 45 in medium scenarios and 60 in heavy. Arrival delay was unaffected by the use of advisory. Total fuel consumption was also reduced by 23 in medium traffic and 33 in heavy. TMI compliance appeared unaffected by the advisory.

System and method for evaluating a wire conductor

DOEpatents

Panozzo, Edward; Parish, Harold

2013-10-22

A method of evaluating an electrically conductive wire segment having an insulated intermediate portion and non-insulated ends includes passing the insulated portion of the wire segment through an electrically conductive brush. According to the method, an electrical potential is established on the brush by a power source. The method also includes determining a value of electrical current that is conducted through the wire segment by the brush when the potential is established on the brush. The method additionally includes comparing the value of electrical current conducted through the wire segment with a predetermined current value to thereby evaluate the wire segment. A system for evaluating an electrically conductive wire segment is also disclosed.

Analysis of the Diurnal Variation of the Global Electric Circuit Obtained From Different Numerical Models

NASA Astrophysics Data System (ADS)

Jánský, Jaroslav; Lucas, Greg M.; Kalb, Christina; Bayona, Victor; Peterson, Michael J.; Deierling, Wiebke; Flyer, Natasha; Pasko, Victor P.

2017-12-01

This work analyzes different current source and conductivity parameterizations and their influence on the diurnal variation of the global electric circuit (GEC). The diurnal variations of the current source parameterizations obtained using electric field and conductivity measurements from plane overflights combined with global Tropical Rainfall Measuring Mission satellite data give generally good agreement with measured diurnal variation of the electric field at Vostok, Antarctica, where reference experimental measurements are performed. An approach employing 85 GHz passive microwave observations to infer currents within the GEC is compared and shows the best agreement in amplitude and phase with experimental measurements. To study the conductivity influence, GEC models solving the continuity equation in 3-D are used to calculate atmospheric resistance using yearly averaged conductivity obtained from the global circulation model Community Earth System Model (CESM). Then, using current source parameterization combining mean currents and global counts of electrified clouds, if the exponential conductivity is substituted by the conductivity from CESM, the peak to peak diurnal variation of the ionospheric potential of the GEC decreases from 24% to 20%. The main reason for the change is the presence of clouds while effects of 222Rn ionization, aerosols, and topography are less pronounced. The simulated peak to peak diurnal variation of the electric field at Vostok is increased from 15% to 18% from the diurnal variation of the global current in the GEC if conductivity from CESM is used.

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

NASA Astrophysics Data System (ADS)

Babauta, Jerome T.; Beyenal, Haluk

2017-07-01

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

An evaluation of airborne nickel, zinc, and lead exposure at hot dip galvanizing plants.

PubMed

Verma, D K; Shaw, D S

1991-12-01

Industrial hygiene surveys were conducted at three hot dip galvanizing plants to determine occupational exposure to nickel, zinc, and lead. All three plants employed the "dry process" and used 2% nickel, by weight, in their zinc baths. A total of 32 personal and area air samples were taken. The air samples were analyzed for nickel, zinc, and lead. Some samples were also analyzed for various species of nickel (i.e., metallic, soluble, and oxidic). The airborne concentrations observed for nickel and its three species, zinc, and lead at the three plants were all well below the current and proposed threshold limit values recommended by the American Conference of Governmental Industrial Hygienists (ACGIH).

Anomaly Detection in Power Quality at Data Centers

NASA Technical Reports Server (NTRS)

Grichine, Art; Solano, Wanda M.

2015-01-01

The goal during my internship at the National Center for Critical Information Processing and Storage (NCCIPS) is to implement an anomaly detection method through the StruxureWare SCADA Power Monitoring system. The benefit of the anomaly detection mechanism is to provide the capability to detect and anticipate equipment degradation by monitoring power quality prior to equipment failure. First, a study is conducted that examines the existing techniques of power quality management. Based on these findings, and the capabilities of the existing SCADA resources, recommendations are presented for implementing effective anomaly detection. Since voltage, current, and total harmonic distortion demonstrate Gaussian distributions, effective set-points are computed using this model, while maintaining a low false positive count.

Study on Spacelab software development and integration concepts

NASA Technical Reports Server (NTRS)

1974-01-01

A study was conducted to define the complexity and magnitude of the Spacelab software challenge. The study was based on current Spacelab program concepts, anticipated flight schedules, and ground operation plans. The study was primarily directed toward identifying and solving problems related to the experiment flight application and tests and checkout software executing in the Spacelab onboard command and data management subsystem (CDMS) computers and electrical ground support equipment (EGSE). The study provides a conceptual base from which it is possible to proceed into the development phase of the Software Test and Integration Laboratory (STIL) and establishes guidelines for the definition of standards which will ensure that the total Spacelab software is understood prior to entering development.

Head shop compound abuse amongst attendees of the Drug Treatment Centre Board.

PubMed

McNamara, S; Stokes, S; Coleman, N

2010-05-01

The use of "Head Shop" compounds has received much media attention lately. There is very little research in the current literature with regard to the extent of the usage of these substances amongst the drug using population in Ireland. We conducted a study to examine the extent of the usage of Mephedrone, Methylone and BZP amongst attendees of Methadone maintenance programs at the DTCB. Two hundred and nine samples in total were tested. The results showed significant usage of these compounds amongst this cohort of drug users, with 29 (13.9%) of samples tested being positive for Mephedrone, 7 (3.3%) positive for Methylone and 1 (0.5%) positive for BZP.

Phase III Integrated Water Recovery Testing at MSFC - Closed hygiene and potable loop test results and lesson learned

NASA Technical Reports Server (NTRS)

Holder, Donald W., Jr.; Bagdigian, Robert M.

1992-01-01

A series of tests has been conducted at the NASA Marshall Space Flight Center (MSFC) to evaluate the performance of a Space Station Freedom (SSF) pre-development water recovery system. Potable, hygiene, and urine reclamation subsystems were integrated with end-use equipment items and successfully operated for a total of 35 days, including 23 days in closed-loop mode with man-in-the-loop. Although several significant subsystem physical anomalies were encountered, reclaimed potable and hygiene water routinely met current SSF water quality specifications. This paper summarizes the test objectives, system design, test activities/protocols, significant results/anomalies, and major lessons learned.

Utilization of artificial intelligence techniques for the Space Station power system

NASA Technical Reports Server (NTRS)

Evatt, Thomas C.; Gholdston, Edward W.

1988-01-01

Due to the complexity of the Space Station Electrical Power System (EPS) as currently envisioned, artificial intelligence/expert system techniques are being investigated to automate operations, maintenance, and diagnostic functions. A study was conducted to investigate this technology as it applies to failure detection, isolation, and reconfiguration (FDIR) and health monitoring of power system components and of the total system. Control system utilization of expert systems for load scheduling and shedding operations was also researched. A discussion of the utilization of artificial intelligence/expert systems for Initial Operating Capability (IOC) for the Space Station effort is presented along with future plans at Rocketdyne for the utilization of this technology for enhanced Space Station power capability.

Numerical simulation of three-component multiphase flows at high density and viscosity ratios using lattice Boltzmann methods

NASA Astrophysics Data System (ADS)

Haghani Hassan Abadi, Reza; Fakhari, Abbas; Rahimian, Mohammad Hassan

2018-03-01

In this paper, we propose a multiphase lattice Boltzmann model for numerical simulation of ternary flows at high density and viscosity ratios free from spurious velocities. The proposed scheme, which is based on the phase-field modeling, employs the Cahn-Hilliard theory to track the interfaces among three different fluid components. Several benchmarks, such as the spreading of a liquid lens, binary droplets, and head-on collision of two droplets in binary- and ternary-fluid systems, are conducted to assess the reliability and accuracy of the model. The proposed model can successfully simulate both partial and total spreadings while reducing the parasitic currents to the machine precision.

A reaction cell with sample laser heating for in situ soft X-ray absorption spectroscopy studies under environmental conditions.

PubMed

Escudero, Carlos; Jiang, Peng; Pach, Elzbieta; Borondics, Ferenc; West, Mark W; Tuxen, Anders; Chintapalli, Mahati; Carenco, Sophie; Guo, Jinghua; Salmeron, Miquel

2013-05-01

A miniature (1 ml volume) reaction cell with transparent X-ray windows and laser heating of the sample has been designed to conduct X-ray absorption spectroscopy studies of materials in the presence of gases at atmospheric pressures. Heating by laser solves the problems associated with the presence of reactive gases interacting with hot filaments used in resistive heating methods. It also facilitates collection of a small total electron yield signal by eliminating interference with heating current leakage and ground loops. The excellent operation of the cell is demonstrated with examples of CO and H2 Fischer-Tropsch reactions on Co nanoparticles.

Eddy current spectroscopy for near-surface residual stress profiling in surface treated nonmagnetic engine alloys

NASA Astrophysics Data System (ADS)

Abu-Nabah, Bassam A.

Recent research results indicated that eddy current conductivity measurements can be exploited for nondestructive evaluation of near-surface residual stresses in surface-treated nickel-base superalloy components. Most of the previous experimental studies were conducted on highly peened (Almen 10-16A) specimens that exhibit harmful cold work in excess of 30% plastic strain. Such high level of cold work causes thermo-mechanical relaxation at relatively modest operational temperatures; therefore the obtained results were not directly relevant to engine manufacturers and end users. The main reason for choosing peening intensities in excess of recommended normal levels was that in low-conductivity engine alloys the eddy current penetration depth could not be forced below 0.2 mm without expanding the measurements above 10 MHz which is beyond the operational range of most commercial eddy current instruments. As for shot-peened components, it was initially felt that the residual stress effect was more difficult to separate from cold work, texture, and inhomogeneity effects in titanium alloys than in nickel-base superalloys. In addition, titanium alloys have almost 50% lower electric conductivity than nickel-base superalloys; therefore require proportionally higher inspection frequencies, which was not feasible until our recent breakthrough in instrument development. Our work has been focused on six main aspects of this continuing research, namely, (i) the development of an iterative inversion technique to better retrieve the depth-dependent conductivity profile from the measured frequency-dependent apparent eddy current conductivity (AECC), (ii) the extension of the frequency range up to 80 MHz to better capture the peak compressive residual stress in nickel-base superalloys using a new eddy current conductivity measuring system, which offers better reproducibility, accuracy and measurement speed than the previously used conventional systems, (iii) the lift-off effect on high frequency eddy current spectroscopy, (iv) the development of custom-made spiral coils to allow eddy current conductivity characterization over the whole frequency range of interest with reduced coil sensitivity to lift off, (v) the benefits of implementing a semi-quadratic system calibration in reducing the coil sensitivity to lift-off, and (vi) the feasibility of adapting high-frequency eddy current residual stress characterization for shot-peened titanium alloys.

Evaluation of Total Nitrite Pattern Visualization as an Improved Method for Gunshot Residue Detection and its Application to Casework Samples.

PubMed

Berger, Jason; Upton, Colin; Springer, Elyah

2018-04-23

Visualization of nitrite residues is essential in gunshot distance determination. Current protocols for the detection of nitrites include, among other tests, the Modified Griess Test (MGT). This method is limited as nitrite residues are unstable in the environment and limited to partially burned gunpowder. Previous research demonstrated the ability of alkaline hydrolysis to convert nitrates to nitrites, allowing visualization of unburned gunpowder particles using the MGT. This is referred to as Total Nitrite Pattern Visualization (TNV). TNV techniques were modified and a study conducted to streamline the procedure outlined in the literature to maximize the efficacy of the TNV in casework, while reducing the required time from 1 h to 5 min, and enhancing effectiveness on blood-soiled samples. The TNV method was found to provide significant improvement in the ability to detect significant nitrite residues, without sacrificing efficiency, that would allow for the determination of the muzzle-to-target distance. © 2018 American Academy of Forensic Sciences.

Assessment of the Fishery Improvement Opportunities on the Pend Oreille River, 1989 Annual Report.

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

Barber, Michael R.; Renberg, Becky L.; Vella, John J.

1990-09-01

The purpose of this study was to assess the fishery improvement opportunities on the Box Canyon portion of the Pend Oreille River. This three year study was initiated as part of the Northwest Power Planning Council's 1987 Columbia River Basin Fish and Wildlife Program. This report contains the findings of the second year of the study. Currently, yellow perch (Perca flavescens (Mitchill)) are the predominant fish species in the river and largemouth bass (Micropterus salmoides (Lacepede)) are the predominant sport fish. The objectives of the second year of the study were to determine: the relative abundance of each species inmore » the river and sloughs; the population levels in five selected tributaries and, if possible, for fish in the river and sloughs; fish growth rates; the feeding habits and abundance of preferred prey; migration patterns; and the total fishing pressure, catch-per-unit-effort, and total harvest by conducting a year-round creel survey. 55 refs., 7 figs., 154 tabs.« less

The effect of urea on refractometric total protein measurement in dogs and cats with azotemia.

PubMed

Legendre, Kelsey P; Leissinger, Mary; Le Donne, Viviana; Grasperge, Britton J; Gaunt, Stephen D

2017-03-01

While protein is the predominant solute measured in plasma or serum by a refractometer, nonprotein substances also contribute to the angle of refraction. There is debate in the current literature regarding which nonprotein substances cause factitiously high refractometric total protein measurements, as compared to the biuret assay. The purpose of the study was to determine if the blood of azotemic animals, specifically with increased blood urea concentration, will have significantly higher refractometric total protein concentrations compared to the total protein concentrations measured by biuret assay. A prospective case series was conducted by collecting data from azotemic (n = 26) and nonazotemic (n = 34) dogs and cats. In addition, an in vitro study was performed where urea was added to an enhanced electrolyte solution at increasing concentrations, and total protein was assessed by both the refractometer and spectrophotometer. Statistical analysis was performed to determine the effect of urea. The refractometric total protein measurement showed a positive bias when compared to the biuret protein measurement in both groups, but the bias was higher in the azotemic group vs the nonazotemic group. The mean difference in total protein measurements of the nonazotemic group (0.59 g/dL) was significantly less (P < .01) than the mean difference of the azotemic group (0.95 g/dL). The in vitro experiment revealed a positive bias with a proportional error. This study demonstrated that increasing concentrations of urea significantly increased the total protein concentration measured by the refractometer as compared to the biuret assay, both in vivo and in vitro. © 2017 American Society for Veterinary Clinical Pathology.

Modelling the Effect of Fruit Growth on Surface Conductance to Water Vapour Diffusion

PubMed Central

GIBERT, CAROLINE; LESCOURRET, FRANÇOISE; GÉNARD, MICHEL; VERCAMBRE, GILLES; PÉREZ PASTOR, ALEJANDRO

2005-01-01

• Background and Aims A model of fruit surface conductance to water vapour diffusion driven by fruit growth is proposed. It computes the total fruit conductance by integrating each of its components: stomata, cuticle and cracks. • Methods The stomatal conductance is computed from the stomatal density per fruit and the specific stomatal conductance. The cuticular component is equal to the proportion of cuticle per fruit multiplied by its specific conductance. Cracks are assumed to be generated when pulp expansion rate exceeds cuticle expansion rate. A constant percentage of cracks is assumed to heal each day. The proportion of cracks to total fruit surface area multiplied by the specific crack conductance accounts for the crack component. The model was applied to peach fruit (Prunus persica) and its parameters were estimated from field experiments with various crop load and irrigation regimes. • Key Results The predictions were in good agreement with the experimental measurements and for the different conditions (irrigation and crop load). Total fruit surface conductance decreased during early growth as stomatal density, and hence the contribution of the stomatal conductance, decreased from 80 to 20 % with fruit expansion. Cracks were generated for fruits exhibiting high growth rates during late growth and the crack component could account for up to 60 % of the total conductance during the rapid fruit growth. The cuticular contribution was slightly variable (around 20 %). Sensitivity analysis revealed that simulated conductance was highly affected by stomatal parameters during the early period of growth and by both crack and stomatal parameters during the late period. Large fruit growth rate leads to earlier and greater increase of conductance due to higher crack occurrence. Conversely, low fruit growth rate accounts for a delayed and lower increase of conductance. • Conclusions By predicting crack occurrence during fruit growth, this model could be helpful in managing cropping practices for integrated plant protection. PMID:15655107

Effect of lifestyle, education and socioeconomic status on periodontal health

PubMed Central

Gundala, Rupasree; Chava, Vijay K.

2010-01-01

Background: The health model which forms the basis is knowledge, attitude, temporary, and permanent behaviors. Currently, more emphasis has been directed towards the combined influence of lifestyle, education, levels and socioeconomic factors, instead of regular risk factors in dealing with chronic illnesses. The present study is conducted to correlate the periodontal health of people with reference to lifestyle, education level, and socioeconomic status. Materials and Methods: A cross-sectional study was conducted in the Department of Periodontics, Narayana Dental College and Hospital, Nellore. A total of 1350 subjects were examined and 948 patients were randomly selected from out patient department. Information about their lifestyle, education level, and socioeconomic status were recorded using a questionnaire and correlated with the periodontal status. Results: The statistical analysis showed significant decrease in periodontitis when income and education levels increased. Also the prevalence of periodontitis associated with a healthy lifestyle is significantly lower when compared to an unhealthy lifestyle. Conclusions: There is a strong association of lifestyle, education level, and socioeconomic status with periodontal health. PMID:22114373

Non-Heat Treatable Alloy Sheet Products

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

Hayden, H.W.; Barthold, G.W.; Das, S.K.

ALCAR is an innovative approach for conducting multi-company, pre-competitive research and development programs. ALCAR has been formed to crate a partnership of aluminum producers, the American Society of Mechanical Engineers Center for Research and Technology Development (ASME/CRTD), the United States Department of Energy (USDOE), three USDOE National Laboratories, and a Technical Advisory Committee for conducting cooperative, pre-competitive research on the development of flower-cost, non-heat treated (NHT) aluminum alloys for automotive sheet applications with strength, formability and surface appearance similar to current heat treated (HT) aluminum alloys under consideration. The effort has been supported by the USDOE, Office of Transportation Technologymore » (OTT) through a three-year program with 50/50 cost share at a total program cost of $3 million. The program has led to the development of new and modified 5000 series aluminum ally compositions. Pilot production-size ingots have bee n melted, cast, hot rolled and cold rolled. Stamping trials on samples of rolled product for demonstrating production of typical automotive components have been successful.« less

Cytotopographical specialization of enzymatically isolated rabbit retinal Müller (glial) cells: K+ conductivity of the cell membrane.

PubMed

Reichenbach, A; Eberhardt, W

1988-01-01

Müller (radial glial) cells were isolated from rabbit retinae by means of papaine and mechanical dissociation. Regional membrane properties of these cells were studied by intracellular microelectrode recordings of potential responses to local application of high K+ solutions. When different parts of the cell membrane were exposed to high K+, the amplitude of the depolarizing responses varied greatly, indicating a strong regional specialization of the membrane properties. Using morphometrical data of isolated rabbit Müller cells, and a simple circuit model, we calculated the endfoot membrane to constitute more than 80% of the total K+ conductance of the cell; the specific resistivity of the endfoot membrane was about 400 omega cm2, i.e., more than 40 times less than that of the membrane of the vitread process, which is immediately adjacent. This kind of regional membrane specialization seems to be optimized in respect to the Müller cells' ability to carry spatial buffering K+ currents.

Recompressed exfoliated graphite articles

DOEpatents

Zhamu, Aruna; Shi, Jinjun; Guo, Jiusheng; Jang, Bor Z

2013-08-06

This invention provides an electrically conductive, less anisotropic, recompressed exfoliated graphite article comprising a mixture of (a) expanded or exfoliated graphite flakes; and (b) particles of non-expandable graphite or carbon, wherein the non-expandable graphite or carbon particles are in the amount of between about 3% and about 70% by weight based on the total weight of the particles and the expanded graphite flakes combined; wherein the mixture is compressed to form the article having an apparent bulk density of from about 0.1 g/cm.sup.3 to about 2.0 g/cm.sup.3. The article exhibits a thickness-direction conductivity typically greater than 50 S/cm, more typically greater than 100 S/cm, and most typically greater than 200 S/cm. The article, when used in a thin foil or sheet form, can be a useful component in a sheet molding compound plate used as a fuel cell separator or flow field plate. The article may also be used as a current collector for a battery, supercapacitor, or any other electrochemical cell.

Development of an integrative algorithm for the treatment of various stages of full-thickness burns of the first commissure of the hand.

PubMed

Yuste, Valentin; Delgado, Julio; Agullo, Alberto; Sampietro, Jose Mauel

2017-06-01

Burns of the first commissure of the hand can evolve into an adduction contracture of the thumb. We decided to conduct a review of the existing literature on the treatment of full-thickness burns of the first commissure in order to develop a treatment algorithm that integrates the various currently available procedures. A search of the existing literature was conducted, focusing on the treatment of a burn of the first commissure in its chronic and acute phases. A total of 29 relevant articles were selected; 24 focused exclusively on the chronic contracture stage, while 3 focused exclusively on the acute burn stage, and 2 articles studied both stages. A therapeutic algorithm for full-thickness burns of the first commissure of the hand was developed. With this algorithm we sought to relate each degree and stage of the burn with a treatment. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

Changing rates of suicide ideation and attempts among Inuit youth: a gender-based analysis of risk and protective factors.

PubMed

Fraser, Sarah L; Geoffroy, Dominique; Chachamovich, Eduardo; Kirmayer, Laurence J

2015-04-01

Inuit in Canada currently suffer from one of the highest rates of suicide in the world. The objective of this study was to explore the prevalence of suicide ideations and attempts among 15-24 year olds living in Nunavik, Québec, and to explore risk and protective factors of suicide attempts as a function of gender. A cross-sectional survey was conducted in 2004 across Nunavik. Univariate and multivariate logistic regressions were conducted. A total of 22% of young males and 39% of females adults reported past suicidal attempts. Gender differences were observed in relation to associated risk and protective factors as well as degree of exposure to risk factors. Suicide prevention must include alcohol and drug prevention programs and rehabilitation services, interventions to reduce physical and sexual violence and their long-term impacts on Inuit youth, as well as exposure to culturally meaningful activities. © 2014 The American Association of Suicidology.

Evaluating the effectiveness of student assistance programs in Pennsylvania.

PubMed

Fertman, C I; Fichter, C; Schlesinger, J; Tarasevich, S; Wald, H; Zhang, X

2001-01-01

This article presents data from an evaluation of the Pennsylvania Student Assistance Program (SAP). Focusing on both program process and effectiveness, the evaluation was conducted to determine the overall efficacy of SAPs in Pennsylvania and, more specifically, how SAP is currently being implemented. Five data collection strategies were employed: statewide surveys of SAP team members and county administrators, focus groups, site visits, and the Pennsylvania Department of Education SAP Database. A total of 1204 individual team members from 154 school buildings completed the team member survey. Fifty-three county administrators completed the county administrator survey. Focus groups were comprised of SAP coordinators, school board personnel and community agency staff. Site visits were conducted at five schools. The findings of the evaluation indicate that SAP in Pennsylvania is being implemented as designed. Recommended is the development of benchmarks and indicators that focus on the best SAP practices and the extent to which various indicators of the effectiveness of SAP are occurring at appropriate levels.

Measurement of the para-hydrogen concentration in the ISIS moderators using neutron transmission and thermal conductivity

NASA Astrophysics Data System (ADS)

Romanelli, Giovanni; Rudić, Svemir; Zanetti, Matteo; Andreani, Carla; Fernandez-Alonso, Felix; Gorini, Giuseppe; Krzystyniak, Maciej; Škoro, Goran

2018-04-01

We present an experimental study to determine the para-hydrogen concentration in the hydrogen moderators at the ISIS pulsed neutron and muon source. The experimental characterisation is based on neutron transmission experiments performed on the VESUVIO spectrometer, and thermal conductivity measurements using the TOSCA para-hydrogen rig. A reliable estimation of the level of para-hydrogen concentration in the hydrogen moderators is of crucial importance in the framework of a current project to completely refurbish the first target station at ISIS. Moreover, we report a new measurement of the total neutron cross section for normal hydrogen at 15 K on the broad energy range 3 meV -10 eV suggesting a revision of the most recent nuclear libraries for incident neutron energies lower than 10 meV. Finally, we characterise systematic errors affecting the para-hydrogen level estimation due to conversion from para to ortho hydrogen, as a function of the time a batch of gas spends in every component of our gas panel and apparatus.

Tampa Bay environmental atlas

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

Kunneke, J.T.; Palik, T.F.

1984-12-01

Biological and water resource data for Tampa Bay were compiled and mapped at a scale of 1:24,000. This atlas consists of (1) composited information overlain on 18 biological and 20 water resource base maps and (2) an accompanying map narrative. Subjects mapped on the water resource maps are contours of the mean middepth specific conductivity which can be converted to salinity; bathymetry, sediments, tidal currents, the freshwater/saltwater interface, dredge spoil disposal sites; locations of industrial and municipal point source discharges, tide stations, and water quality sampling stations. The point source discharge locations show permitted capacity and the water quality samplingmore » stations show 5-year averages for chlorophyll, conductivity, turbidity, temperature, and total nitrogen. The subjects shown on the biological resource maps are clam and oyster beds, shellfish harvest areas, colonial bird nesting sites, manatee habitat, seagrass beds and artificial reefs. Spawning seasons, nursery habitats, and adult habitats are identified for major fish species. The atlas will provide useful information for coastal planning and management in Tampa Bay.« less

Impact of Soil Composition and Electrochemistry on Corrosion of Rock-cut Slope Nets along Railway Lines in China.

PubMed

Chen, Jiao; Chen, Zhaoqiong; Ai, Yingwei; Xiao, Jingyao; Pan, Dandan; Li, Wei; Huang, Zhiyu; Wang, Yumei

2015-10-09

Taking the slope of Suiyu Railway to study, the research separately studied soil resistivity, soil electrochemistry (corrosion potential, oxidization reduction potential, electric potential gradient and pH), soil anions (total soluble salt, Cl(-), SO4(2-) and ), and soil nutrition (moisture content, organic matter, total nitrogen, alkali-hydrolysable nitrogen, available phosphorus, and available potassium) at different slope levels, and conducted corrosion grade evaluation on artificial soil according to its single index and comprehensive indexes. Compared with other factors, water has the biggest impact on the corrosion of slope protection net, followed by anion content. Total soluble salt has the moderate impact on the corrosion of slope protection net, and stray current has the moderate impact on the corrosion of mid-slope protection net. Comprehensive evaluation on the corrosive degree of soil samples indicates that the corrosion of upper slope is moderate, and the corrosion of mid-slope and lower slope is strong. Organic matter in soil is remarkably relevant to electric potential gradient. Available nitrogen, available potassium and available phosphorus are remarkably relevant to anions. The distribution of soil nutrient is indirectly relevant to slope type.

Impact of Soil Composition and Electrochemistry on Corrosion of Rock-cut Slope Nets along Railway Lines in China

PubMed Central

Chen, Jiao; Chen, Zhaoqiong; Ai, Yingwei; Xiao, Jingyao; Pan, Dandan; Li, Wei; Huang, Zhiyu; Wang, Yumei

2015-01-01

Taking the slope of Suiyu Railway to study, the research separately studied soil resistivity, soil electrochemistry (corrosion potential, oxidization reduction potential, electric potential gradient and pH), soil anions (total soluble salt, Cl−, SO42− and ), and soil nutrition (moisture content, organic matter, total nitrogen, alkali-hydrolysable nitrogen, available phosphorus, and available potassium) at different slope levels, and conducted corrosion grade evaluation on artificial soil according to its single index and comprehensive indexes. Compared with other factors, water has the biggest impact on the corrosion of slope protection net, followed by anion content. Total soluble salt has the moderate impact on the corrosion of slope protection net, and stray current has the moderate impact on the corrosion of mid-slope protection net. Comprehensive evaluation on the corrosive degree of soil samples indicates that the corrosion of upper slope is moderate, and the corrosion of mid-slope and lower slope is strong. Organic matter in soil is remarkably relevant to electric potential gradient. Available nitrogen, available potassium and available phosphorus are remarkably relevant to anions. The distribution of soil nutrient is indirectly relevant to slope type. PMID:26450811

Elimination of current spikes in buck power converters

NASA Technical Reports Server (NTRS)

Mclyman, W. T. (Inventor)

1981-01-01

Current spikes in a buck power converter due to commutating diode turn-off time are eliminated by using a tapped inductor in the converter with the tap connected to the switching transistor. The commutating diode is not in the usual place, but is instead connected to conduct current from one end of the tapped inductor remote from the load during the interval in which the transistor is not conducting. In the case of a converter having a center-tapped (primary and secondary) transformer between two switching power transistors operated in a push-pull mode and two rectifying diodes in the secondary circuit, current spikes due to transformer saturation are also eliminated by using a tapped inductor in the converter with the tap connected to the rectifying diodes and a diode connected to conduct current from one end of the tapped inductor remote from the load during the interval in which the transistors are not conducting.

Effect of Ground Layer Patterns with Slits on Conducted Noise Currents from Printed Circuit Board

NASA Astrophysics Data System (ADS)

Maeno, Tsuyoshi; Unou, Takanori; Ichikawa, Kouji; Fujiwara, Osamu

Electromagnetic disturbances for vehicle-mounted radios can be caused by conducted noise currents that flows out from electronic equipment for vehicles to wire-harnesses. In this paper, for reducing the conducted noise currents from electronic equipment for vehicles, we made a simulation and experiment on how ground patterns affect the noise currents from three-layer printed circuit boards (PCBs) with slit-types and plane-type ground patterns. As a result, we could confirm that slits on a ground pattern allow conducted noise currents to flow out from PCBs to wire-harnesses. For the PCBs with plane-type ground and one of three slit-type patterns, on the other hand, both the simulation and examination showed that resonance phenomena occur at unexpected low-frequencies. A circuit analysis revealed that the above phenomena can be caused by the imbalance of a bridge circuit consisting of the trace circuits on the PCB.

The Association between Tobacco Smoke and Serum Immunoglobulin E Levels in Korean Adults.

PubMed

Kim, Young Soo; Kim, Hee Yeon; Ahn, Hyo-Suk; Sohn, Tae Seo; Song, Jae Yen; Lee, Young Bok; Lee, Dong-Hee; Lee, Jae-Im; Jeong, Seong Cheol; Chae, Hiun Suk; Han, Kyungdo; Yeo, Chang Dong

2017-10-01

Objective Smoking is common in patients with allergic diseases. The aim of this study was to evaluate the cross-sectional association between the current smoking status and total and specific Immunoglobulin E (IgE) levels in Korean adults. Methods Data were obtained from the 2010 Korean National Health and Nutrition Examination Survey, a national cross-sectional study. We analyzed the data of subjects whose smoking status and serum IgE levels were of acceptable quality. Results A total of 1,963 subjects (1,118 never smokers, 340 ex-smokers, and 505 current smokers) were included. The total IgE levels and specific IgE levels to house dust mite Dermatophagoides farinae (Df), cockroach, and dog allergens in never smokers were significantly (p<0.0001) lower than in ex-smokers or current smokers. After adjusting for other variables, current smokers independently had significantly higher levels of total IgE and cockroach-specific IgE than ex-smokers or never smokers. The proportions of subjects with total IgE ≥150 kU/L and specific IgE ≥0.35 kU/L to Df-specific IgE were significantly (p value for trend <0.05) increased in ex-smokers and current smokers. The total IgE levels and IgE levels specific to Df, cockroaches, and dogs significantly (p value for trend <0.05) and proportionally increased with increasing numbers of cigarettes smoked daily. Conclusion Smoking was associated with elevated total IgE levels and IgE levels specific to Df, cockroach, and dog allergens in a cumulative, dose-dependent manner. Furthermore, current smoking status was an independent risk factor for elevated total IgE levels and IgE levels specific to cockroach allergen.

COMMUNITY SCALE STREAM TAXA SENSITIVITIES TO DIFFERENT COMPOSITIONS OF EXCESS TOTAL DISSOLVED SOLIDS

EPA Science Inventory

Model stream chronic dosing studies (42 d) were conducted with three total dissolved solids (TDS) recipes. The recipes differed in composition of major ions. Community scale emergence was compared with single-species responses conducted simultaneously using the whole effluent tox...

The influence of the footplate-perilymph interface on postoperative bone conduction.

PubMed

Arnold, Wolfgang; Ferekidis, Elefterios; Hamann, Karl-Friedrich

2007-01-01

In a prospective study, 165 total stapedectomies and 152 small fenestra stapedotomies were performed by three experienced surgeons between 2001 and 2003. In total stapedectomy, a self-made Schuknecht steel wire connective tissue prosthesis, and in stapedotomy, a 0.6-mm platinum wire Teflon piston was used. The pre- and postoperative bone conduction thresholds were compared at the frequencies 250 Hz, 500 Hz, 1 kHz, 1.5 kHz, 2 kHz, 3 kHz and 4 kHz. The postoperative bone conduction between 250 Hz and 3 kHz was significantly better in the total stapedectomy group than in the stapedotomy group. At 4 kHz, both groups showed a slight decrease in bone conduction but the difference was not statistically significant. Therefore, especially in cases with preoperative moderate sensorineural hearing loss, we recommend total stapedectomy using a Schuknecht steel wire connective tissue prosthesis, which offers a stapes-perilymph interface similar to the normal stapes.

The branching of the Gulf Stream southeast of the Grand Banks

NASA Astrophysics Data System (ADS)

Krauss, W.; KäSe, R. H.; Hinrichsen, H.-H.

1990-08-01

During March-April 1987, 101 hydrographic stations were occupied on three sections spanning a triangle between the Azores (Faial), the southern tip of the Grand Banks of Newfoundland, and Bermuda. Information on the near-surface processes in the interior of the triangle were obtained from 32 satellite-tracked buoys deployed during the cruise and a composite infrared image based on cloud-free NOAA 9 data during April 1987. The data were combined to analyze the eddy field and the branching of the Gulf Stream into the North Atlantic Current and the Azores Current. Calculations of mass transports through the legs of the triangle gave a total of 46 Sv supplied by the Gulf Stream, 31 Sv of which left the area as the North Atlantic Current and westwind drift north of the Azores. The remaining 14 Sv continued towards east-southeast as the Azores Current and southern recirculation. Additional conductivity-temperature-depth stations from a cruise in April 1986 into the same area allowed also study of the large-scale circulation within that triangle in deeper layers. The Azores Current appears as a baroclinic stream which reaches down to approximately 1000 m. Intensive mixing was observed at the continental slope of Newfoundland between water of the Labrador Current and the Gulf Stream (mixed water). Owing to cabbeling and consecutive convective mixing, this water penetrates down to 2000 m depth and creates horizontal density gradients to the surrounding Gulf Stream water, which intensifies the North Atlantic Current. This process is considered to be an important energy source for this current.

Active and passive smoking impacts on asthma with quantitative and temporal relations: A Korean Community Health Survey.

PubMed

Kim, So Young; Sim, Songyong; Choi, Hyo Geun

2018-06-05

This study aimed to evaluate the relations of smoking with asthma and asthma-related symptoms, considering quantitative and temporal influences. The 820,710 Korean adults in the Korean Community Health Survey in 2009, 2010, 2011, and 2013 were included and classified as non-smoker, past smoker or current smoker. Total smoking years, total pack-years, and age at smoking onset were assessed. Information on wheezing, exercise wheezing, and aggravation of asthma in the past 12 months and asthma diagnosis history and current treatment was collected. Multiple logistic regression analysis with complex sampling was used. Current and former smokers showed significant positive relations with wheezing, exercise wheezing, asthma ever, current asthma, and asthma aggravation. Current smokers demonstrated higher adjusted odd ratios (AORs) for wheezing, exercise wheezing, and asthma aggravation than former smokers. Former smokers showed higher AORs than current smokers for current asthma treatment. Longer passive smoking was related to wheezing and exercise wheezing. Greater age at smoking onset and duration since cessation were negatively related to wheezing, exercise wheezing, and current asthma; total pack-years demonstrated proportional associations with these symptoms. Former, current, and passive smoking was positively correlated with wheezing and exercise wheezing. Total pack-years and early initiation were increasingly related to asthma.

Survey of Medical Oncology Status in Korea (SOMOS-K): A National Survey of Medical Oncologists in the Korean Association for Clinical Oncology (KACO).

PubMed

Kim, Do Yeun; Lee, Yun Gyoo; Kim, Bong-Seog

2017-07-01

This study was conducted to investigate the current role of medical oncologists in cancer care with a focus on increasing the recognition of medical oncology as an independent specialty. Questionnaires modified from the Medical Oncology Status in Europe Survey dealing with oncology structure, resources, research, and patterns of care given by medical oncologists were selected. Several modifications were made to the questionnaire after feedback from the insurance and policy committee of the Korean Association for Clinical Oncology (KACO). The online survey was then sent to KACO members. A total of 214 medical oncologists (45.8% of the total inquiries), including 71 directors of medical oncology institutions, took the survey. Most institutions had various resources, including a medical oncology department (94.1%) and a department of radiation oncology (82.4%). There was an average of four medical oncologists at each institution. Medical oncologists were involved in various treatments from diagnosis to end-of-life care. They were also chemotherapy providers from a wide range of institutions that treated many types of solid cancers. In addition, 86.2% of the institutions conducted research. This is the first national survey in Korea to show that medical oncologists are involved in a wide range of cancer treatments and care. This survey emphasizes the contributions and proper roles of medical oncologists in the evolving health care environment in Korea.

Assessment of the St. Louis River AOC fish tumors and other ...

EPA Pesticide Factsheets

The Fish Tumors and Other Deformities Beneficial Use Impairment (BUI) was listed as one of nine BUIs at the time the St. Louis River AOC was designated in 1987. At the time, no formal studies had been conducted to estimate the prevalence of either fish tumors or deformities. To assess the current status of fish tumors and deformities in the AOC, adult white suckers (Catostomus commersonii) were sampled during the spawning period in May during 2011, 2013 and 2015. We measured each fish, determined its sex and age (sagittal otolith), sampled dorsal muscle tissue for carbon and nitrogen stable isotope ratios to determine river versus lake residency, and conducted a necropsy-based assessment to document grossly visible abnormalities. Pieces of any observable abnormalities were preserved for subsequent histological analyses. A total of 622 white sucker were surveyed from 2011 through 2015. Of these, 27 (4.3%) white suckers had skin neoplasms, all of which were papillomas. A total of 29 (4.7%) of the white suckers had liver neoplasms. Sex and age were significantly associated with skin neoplasia incidence, whereas only age was significantly associated with liver neoplasia incidence. Neither neoplasia type was significantly associated with habitat use, indicating that neoplasia incidence did not change with increasing feeding in the AOC relative to Lake Superior. Further, there was not a significant difference in skin or liver neoplasia incidence between migratory whit

Prevalence of migraine and co-morbid psychiatric disorders among students of Cumhuriyet University

PubMed Central

2013-01-01

Backround The aim of this study was to investigate the prevalence of migraine and associated psychiatric disorders among university students at Cumhuriyet University of Sivas in Turkey. Methods A total of 1601 university students participated in this study and answered the questionnaires. The study was conducted in three stages: the self-questionnaire, the neurological evaluation, and the psychiatric evaluation. In the first stage, the subjects completed a questionnaire to assess migraine symptoms. In the second stage, the subjects who reported having migraines underwent a detailed neurological evaluation conducted by a neurologist to confirm the diagnosis. In the final stage, the subjects with migraines completed a psychiatric examination using the structured clinical interview for DSM IV-R Axis I. Results The self-reported migraine prevalence rate was 13.7%, and the actual prevalence rate of migraine among the university students was calculated to be 10.6% (n = 169). When the results obtained with the SCID-I were examined, a current SCID-I psychiatric diagnosis was found in 39 (23.1%) of the 169 subjects with migraines. A total of 73 (43.2%) students with migraines had a lifetime SCID-I psychiatric diagnosis. Conclusions The results of this study indicate that migraines were highly prevalent among university students in Turkey with comorbid psychiatric disorders. Treatment strategies must be developed to manage these comorbidities. PMID:23578213

A systematic review of multivitamin-multimineral use and cardiovascular disease and cancer incidence and total mortality.

PubMed

Alexander, Dominik D; Weed, Douglas L; Chang, Ellen T; Miller, Paige E; Mohamed, Muhima A; Elkayam, Laura

2013-01-01

Multivitamin-multimineral (MVM) supplements are the most frequently used dietary supplements in the United States, with one third or more of the population using at least one daily. However, the health-related implications of MVM use are unclear. Thus, we systematically reviewed and summarized the prospective studies of MVM supplementation and all-cause and cause-specific mortality, as well as cardiovascular disease (CVD) and cancer incidence, to critically evaluate the current evidence on this topic. We included studies of generally healthy adult populations that evaluated multivitamin (the most commonly used dietary supplement) and/or multimineral supplement use or simultaneous use of 3 or more vitamins and minerals. We did not evaluate individual supplements. A total of 12 cohort studies and 3 primary prevention randomized controlled trials met our inclusion criteria. The majority of the studies were conducted in the United States (n = 11), and the remaining were conducted in European countries (n = 3) and Japan (n = 1). Although between-study methodological variation was present, most relative risks hovered closely around or slightly below the null value. No clear patterns of associations by study country, gender, smoking status, or frequency of use were observed. Based upon the available scientific evidence to date, supplementation with MVMs does not appear to increase all-cause mortality, cancer incidence or mortality, or CVD incidence or mortality and may provide a modest protective benefit.

[Financial impact of introducing filmless CRT diagnosis].

PubMed

Kusakabe, Yukihiro

2002-09-01

There has been a great deal of discussion as to the cost and benefit of introducing filmless CRT diagnosis for radiological exams. Although the various advantages of the filmless system tend to be highlighted, very few studies have attempted to provide a quantitative estimate of the degree of impact. We analyzed the potential financial impact on the cost of film management (film development, maintenance, and transportation) if CRT diagnosis were to be introduced in Seirei Hamamatsu Hospital. In conducting this analysis, we assumed that CRT diagnosis initially would be limited to CT and MR. The analysis demonstrated that the actual yearly cost of managing films amounts to about 240 million yen. As individual items, the cost of film materials, labor, and depreciation of assets were the three largest cost sectors, with the cost of film accounting for more than 30% of the total. The expense attributable to CT and MR exams was roughly half of the total cost. Against this level of expense, the expected savings in the first year after shifting to the filmless system would be 100 million yen, or a 36% reduction in current expenses. This savings reflects various effects of system change, including lack of need for related materials, reduction in staff workload, elimination of unnecessary equipment, etc. Under the simulation we conducted, 70% of savings occurred in the area of variable costs and 30% in the area of fixed costs.

Identification of regional soil quality factors and indicators: a case study on an alluvial plain (central Turkey)

NASA Astrophysics Data System (ADS)

Şeker, Cevdet; Hüseyin Özaytekin, Hasan; Negiş, Hamza; Gümüş, İlknur; Dedeoğlu, Mert; Atmaca, Emel; Karaca, Ümmühan

2017-05-01

Sustainable agriculture largely depends on soil quality. The evaluation of agricultural soil quality is essential for economic success and environmental stability in rapidly developing regions. In this context, a wide variety of methods using vastly different indicators are currently used to evaluate soil quality. This study was conducted in one of the most important irrigated agriculture areas of Konya in central Anatolia, Turkey, to analyze the soil quality indicators of Çumra County in combination with an indicator selection method, with the minimum data set using a total of 38 soil parameters. We therefore determined a minimum data set with principle component analysis to assess soil quality in the study area and soil quality was evaluated on the basis of a scoring function. From the broad range of soil properties analyzed, the following parameters were chosen: field capacity, bulk density, aggregate stability, and permanent wilting point (from physical soil properties); electrical conductivity, Mn, total nitrogen, available phosphorus, pH, and NO3-N (from chemical soil properties); and urease enzyme activity, root health value, organic carbon, respiration, and potentially mineralized nitrogen (from biological properties). According to the results, the chosen properties were found as the most sensitive indicators of soil quality and they can be used as indicators for evaluating and monitoring soil quality at a regional scale.

Establishing Sprinkling Requirements on Trailers Transporting Market Weight Pigs in Warm and Hot Weather.

PubMed

Kephart, Rebecca; Johnson, Anna; Sapkota, Avi; Stalder, Kenneth; McGlone, John

2014-04-11

This study was conducted July of 2012 in Iowa, in WARM (<26.7 °C) and HOT (≥26.7 °C) weather. Four sprinkling methods were compared, with one treatment being randomly assigned to each load: control- no sprinkling (not applied in HOT weather), pigs only, bedding only, or pigs and bedding. Experiment 1 used 51 loads in WARM- and 86 loads in HOT weather to determine sprinkling effects on pig measures (surface temperature, vocalizations, slips and falls, and stress signs). Experiment 2 used 82 loads in WARM- and 54 loads in HOT weather to determine the sprinkling effects on transport losses (non-ambulatory, dead, and total transport losses). Experiment 1 found that, in WARM weather, there were no differences between sprinkling treatments for surface temperature, vocalizations, or slips and falls (p ≥ 0.18). However, stress signs were 2% greater when sprinkling pigs- or bedding only- compared to control (p = 0.03). Experiment 2 found that, in WARM and HOT weather, sprinkling did not affect non-ambulatory, dead, or total transport losses (p ≥ 0.18). Although the current study did not find any observed sprinkling effects for pig measures or transport losses it is extremely important to note that the inference space of this study is relatively small, so further studies should be conducted to see if these results are applicable to other geographical regions and seasons.

Transparent conductive oxide films embedded with plasmonic nanostructure for light-emitting diode applications.

PubMed

Chuang, Shih-Hao; Tsung, Cheng-Sheng; Chen, Ching-Ho; Ou, Sin-Liang; Horng, Ray-Hua; Lin, Cheng-Yi; Wuu, Dong-Sing

2015-02-04

In this study, a spin coating process in which the grating structure comprises an Ag nanoparticle layer coated on a p-GaN top layer of InGaN/GaN light-emitting diode (LED) was developed. Various sizes of plasmonic nanoparticles embedded in a transparent conductive layer were clearly observed after the deposition of indium tin oxide (ITO). The plasmonic nanostructure enhanced the light extraction efficiency of blue LED. Output power was 1.8 times the magnitude of that of conventional LEDs operating at 350 mA, but retained nearly the same current-voltage characteristic. Unlike in previous research on surface-plasmon-enhanced LEDs, the metallic nanoparticles were consistently deposited over the surface area. However, according to microstructural observation, ITO layer mixed with Ag-based nanoparticles was distributed at a distance of approximately 150 nm from the interface of ITO/p-GaN. Device performance can be improved substantially by using the three-dimensional distribution of Ag-based nanoparticles in the transparent conductive layer, which scatters the propagating light randomly and is coupled between the localized surface plasmon and incident light internally trapped in the LED structure through total internal reflection.

Influence of traditional tobacco use on smoking cessation among American Indians.

PubMed

Daley, Christine M; Faseru, Babalola; Nazir, Niaman; Solomon, Cheree; Greiner, K Allen; Ahluwalia, Jasjit S; Choi, Won S

2011-05-01

To examine the influence of traditional tobacco use on smoking cessation among American Indian adult smokers. A cross-sectional survey of self-identified American Indians was conducted from 2008 to 2009. A total of 998 American Indian adults (18 years and older) from the Midwest participated in the study. Traditional tobacco use and method of traditional use were both assessed. Commercial tobacco use (current smoking) was obtained through self-reported information as well as the length of their most recent quit attempt. We also assessed knowledge and awareness of pharmacotherapy for current smokers. Among participants in our study, 33.3% were current smokers and they reported smoking an average of 10 cigarettes per day. American Indian current smokers who used traditional tobacco reported a greater number of days abstinent during their last quit attempt compared to those who do not use traditional tobacco (P = 0.01). However, it appears that this protective effect of traditional tobacco use is diminished if the person smokes traditional tobacco. Finally, very few (fewer than 20% of current smokers) were aware of more recent forms of pharmacotherapy such as Chantix or bupropion. American Indians appear to show low levels of awareness of effective pharmacotherapies to aid smoking cessation, but those who use 'traditional tobacco' report somewhat longer periods of abstinence from past quit attempts. © 2011 The Authors, Addiction © 2011 Society for the Study of Addiction.

A Qualitative Assessment of the Parenting Challenges and Treatment Needs of Mothers with Borderline Personality Disorder

PubMed Central

Zalewski, Maureen; Stepp, Stephanie D.; Whalen, Diana J.; Scott, Lori N.

2014-01-01

There are currently no empirically supported interventions to target parenting among mothers who have Borderline Personality Disorder (BPD). The current study uses Consensus Qualitative Research (CQR) methodology to: I) learn about mothers’ experiences of parenting with BPD, and II) identify treatment modifications to Dialectical Behavior Therapy (DBT) as suggested by mothers with BPD who are currently engaged in DBT skills training. Twenty-three mothers were recruited from intensive outpatient and partial hospitalization programs that teach DBT skills. A total of 9 focus groups that met one time were conducted asking women a series of questions regarding their experiences of parenting with BPD and how they would modify DBT to address parenting issues. Using the CQR approach, we coded domains and categories that were discussed by mothers in the focus groups. Coding revealed that mothers with BPD wished parenting was integrated more in their current DBT skills groups. In addition, one of the most prominent themes to emerge was that parenting is particularly stressful to mothers with BPD and is associated with guilt, uncertainty, and worry. Finally, mothers offered many ideas for how to integrate parenting-focused interventions into DBT. The CQR method revealed gaps in current treatment for mothers with BPD and provided useful ideas for how to modify DBT to target parenting and integrate these modifications into other approaches for treating mothers with BPD. PMID:26257507

Analysis of microscopic parameters of surface charging in polymer caused by defocused electron beam irradiation.

PubMed

Liu, Jing; Zhang, Hai-Bo

2014-12-01

The relationship between microscopic parameters and polymer charging caused by defocused electron beam irradiation is investigated using a dynamic scattering-transport model. The dynamic charging process of an irradiated polymer using a defocused 30 keV electron beam is conducted. In this study, the space charge distribution with a 30 keV non-penetrating e-beam is negative and supported by some existing experimental data. The internal potential is negative, but relatively high near the surface, and it decreases to a maximum negative value at z=6 μm and finally tend to 0 at the bottom of film. The leakage current and the surface potential behave similarly, and the secondary electron and leakage currents follow the charging equilibrium condition. The surface potential decreases with increasing beam current density, trap concentration, capture cross section, film thickness and electron-hole recombination rate, but with decreasing electron mobility and electron energy. The total charge density increases with increasing beam current density, trap concentration, capture cross section, film thickness and electron-hole recombination rate, but with decreasing electron mobility and electron energy. This study shows a comprehensive analysis of microscopic factors of surface charging characteristics in an electron-based surface microscopy and analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antepartum Care of Women Who Are Obese During Pregnancy: Systematic Review of the Current Evidence.

PubMed

Carlson, Nicole S; Leslie, Sharon Lynn; Dunn, Alexis

2018-05-14

Nearly 40% of US women of childbearing age are obese. Obesity during pregnancy is associated with multiple risks for both the woman and fetus, yet clinicians often feel unprepared to provide optimal antepartum care for this group of women. We collected and reviewed current evidence concerning antepartum care of women who are obese during pregnancy. We conducted a systematic review using PRISMA guidelines. Current evidence relating to the pregnancy care of women with a prepregnancy body mass index of 30kg/m 2 or higher was identified using MEDLINE databases via PubMed, Embase, and Web of Science Core Collection between January 2012 and February 2018. A total of 354 records were located after database searches, of which 63 met inclusion criteria. Topic areas for of included studies were: pregnancy risk and outcomes related to obesity, communication between women and health care providers, gestational weight gain and activity/diet, diabetic disorders, hypertensive disorders, obstructive sleep apnea, mental health, pregnancy imaging and measurement, late antepartum care, and preparation for labor and birth. Midwives and other health care providers can provide better antepartum care to women who are obese during pregnancy by incorporating evidence from the most current clinical investigations. © 2018 by the American College of Nurse-Midwives.

Electromagnetic pulse-driven spin-dependent currents in semiconductor quantum rings.

PubMed

Zhu, Zhen-Gang; Berakdar, Jamal

2009-04-08

We investigate the non-equilibrium charge and spin-dependent currents in a quantum ring with a Rashba spin-orbit interaction (SOI) driven by two asymmetric picosecond electromagnetic pulses. The equilibrium persistent charge and persistent spin-dependent currents are investigated as well. It is shown that the dynamical charge and the dynamical spin-dependent currents vary smoothly with a static external magnetic flux and the SOI provides a SU(2) effective flux that changes the phases of the dynamic charge and the dynamic spin-dependent currents. The period of the oscillation of the total charge current with the delay time between the pulses is larger in a quantum ring with a larger radius. The parameters of the pulse fields control to a certain extent the total charge and the total spin-dependent currents. The calculations are applicable to nanometre rings fabricated in heterojunctions of III-V and II-VI semiconductors containing several hundreds of electrons.

THE RELATIONSHIP OF TOTAL DISSOLVED SOLIDS MEASUREMENTS TO BULK ELECTRICAL CONDUCTIVITY IN AN AQUIFER CONTAMINATED WITH HYDROCARBON

EPA Science Inventory

A recent conceptual model links high bulk electrical conductivities at hydrocarbon impacted sites to higher total dissolved solids (TDS) resulting from enhanced mineral weathering due to acids produced during biodegradation. In this study, we investigated the vertical distributio...

48 CFR 52.209-7 - Information Regarding Responsibility Matters.

Code of Federal Regulations, 2010 CFR

2010-10-01

... connection with performance of a Federal contract or grant. It does not include agency actions such as... with total value greater than $10,000,000 means— (1) The total value of all current, active contracts and grants, including all priced options; and (2) The total value of all current, active orders...

48 CFR 52.209-7 - Information Regarding Responsibility Matters.

Code of Federal Regulations, 2011 CFR

2011-10-01

... connection with performance of a Federal contract or grant. It does not include agency actions such as... with total value greater than $10,000,000 means— (1) The total value of all current, active contracts and grants, including all priced options; and (2) The total value of all current, active orders...

An analysis of collegiate band directors' exposure to sound pressure levels

NASA Astrophysics Data System (ADS)

Roebuck, Nikole Moore

Noise-induced hearing loss (NIHL) is a significant but unfortunate common occupational hazard. The purpose of the current study was to measure the magnitude of sound pressure levels generated within a collegiate band room and determine if those sound pressure levels are of a magnitude that exceeds the policy standards and recommendations of the Occupational Safety and Health Administration (OSHA), and the National Institute of Occupational Safety and Health (NIOSH). In addition, reverberation times were measured and analyzed in order to determine the appropriateness of acoustical conditions for the band rehearsal environment. Sound pressure measurements were taken from the rehearsal of seven collegiate marching bands. Single sample t test were conducted to compare the sound pressure levels of all bands to the noise exposure standards of OSHA and NIOSH. Multiple regression analysis were conducted and analyzed in order to determine the effect of the band room's conditions on the sound pressure levels and reverberation times. Time weighted averages (TWA), noise percentage doses, and peak levels were also collected. The mean Leq for all band directors was 90.5 dBA. The total accumulated noise percentage dose for all band directors was 77.6% of the maximum allowable daily noise dose under the OSHA standard. The total calculated TWA for all band directors was 88.2% of the maximum allowable daily noise dose under the OSHA standard. The total accumulated noise percentage dose for all band directors was 152.1% of the maximum allowable daily noise dose under the NIOSH standards, and the total calculated TWA for all band directors was 93dBA of the maximum allowable daily noise dose under the NIOSH standard. Multiple regression analysis revealed that the room volume, the level of acoustical treatment and the mean room reverberation time predicted 80% of the variance in sound pressure levels in this study.

MEMBRANE POTENTIAL OF THE SQUID GIANT AXON DURING CURRENT FLOW

PubMed Central

Cole, Kenneth S.; Curtis, Howard J.

1941-01-01

The squid giant axon was placed in a shallow narrow trough and current was sent in at two electrodes in opposite sides of the trough and out at a third electrode several centimeters away. The potential difference across the membrane was measured between an inside fine capillary electrode with its tip in the axoplasm between the pair of polarizing electrodes, and an outside capillary electrode with its tip flush with the surface of one polarizing electrode. The initial transient was roughly exponential at the anode make and damped oscillatory at the sub-threshold cathode make with the action potential arising from the first maximum when threshold was reached. The constant change of membrane potential, after the initial transient, was measured as a function of the total polarizing current and from these data the membrane potential is obtained as a function of the membrane current density. The absolute value of the resting membrane resistance approached at low polarizing currents is about 23 ohm cm.2. This low value is considered to be a result of the puncture of the axon. The membrane was found to be an excellent rectifier with a ratio of about one hundred between the high resistance at the anode and the low resistance at the cathode for the current range investigated. On the assumption that the membrane conductance is a measure of its ion permeability, these experiments show an increase of ion permeability under a cathode and a decrease under an anode. PMID:19873234

[Opinion of administrative personnel about smoke-free regulations].

PubMed

Wojtysiak, Piotr; Polańska, Kinga; Bak-Romaniszyn, Leokadia; Czarnecka, Karolina; Kaleta, Dorota

2010-01-01

The aim of the study was to analyze the opinion of administrative personnel in school on smoke-free regulations. The study population consisted of 320 subjects. Among the study population questionnaire was conducted including socio-demographic characteristic, smoking and SHS profile. Detail information was collected about opinion on smoke-free public places such as offices, other workplaces, health and educational buildings, restaurants and bars. About 22% of study population declared current tobacco smoking. More current everyday smoking was observed among men comparing to women (17.8% vs. 9.1%; p < 0.05). The study indicated that high percentage support total ban of smoking in public offices (84%), health care buildings (89%), and educational buildings (86%). 60% of the study subject were in favor of smoke-fee restaurants and 38% sypport smoke-free burs, pubs and clubs. The strong approval for ban on tobacco product advertising was indicated by 41% of respondents and 38% of them expect pictorial warnings on tobacco packs.

High-Potential Metalless Nanocarbon Foam Supercapacitors Operating in Aqueous Electrolyte.

PubMed

Liu, Chueh; Li, Changling; Ahmed, Kazi; Mutlu, Zafer; Lee, Ilkeun; Zaera, Francisco; Ozkan, Cengiz S; Ozkan, Mihrimah

2018-04-01

Light-weight graphite foam decorated with carbon nanotubes (dia. 20-50 nm) is utilized as an effective electrode without binders, conductive additives, or metallic current collectors for supercapacitors in aqueous electrolyte. Facile nitric acid treatment renders wide operating potentials, high specific capacitances and energy densities, and long lifespan over 10 000 cycles manifested as 164.5 and 111.8 F g -1 , 22.85 and 12.58 Wh kg -1 , 74.6% and 95.6% capacitance retention for 2 and 1.8 V, respectively. Overcharge protection is demonstrated by repetitive cycling between 2 and 2.5 V for 2000 cycles without catastrophic structural demolition or severe capacity fading. Graphite foam without metallic strut possessing low density (≈0.4-0.45 g cm -3 ) further reduces the total weight of the electrode. The thorough investigation of the specific capacitances and coulombic efficiencies versus potential windows and current densities provides insights into the selection of operation conditions for future practical devices. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Observation of turnover of spontaneous polarization in ferroelectric layer of pentacene/poly-(vinylidene-trifluoroethylene) double-layer capacitor under photo illumination by optical second-harmonic generation measurement

NASA Astrophysics Data System (ADS)

Shi, Zhemin; Taguchi, Dai; Manaka, Takaaki; Iwamoto, Mitsumasa

2016-04-01

The details of turnover process of spontaneous polarization and associated carrier motions in indium-tin oxide/poly-(vinylidene-trifluoroethylene)/pentacene/Au capacitor were analyzed by coupling displacement current measurement (DCM) and electric-field-induced optical second-harmonic generation (EFISHG) measurement. A model was set up from DCM results to depict the relationship between electric field in semiconductor layer and applied external voltage, proving that photo illumination effect on the spontaneous polarization process lied in variation of semiconductor conductivity. The EFISHG measurement directly and selectively probed the electric field distribution in semiconductor layer, modifying the model and revealing detailed carrier behaviors involving photo illumination effect, dipole reversal, and interfacial charging in the device. A further decrease of DCM current in the low voltage region under illumination was found as the result of illumination effect, and the result was argued based on the changing of the total capacitance of the double-layer capacitors.

Aerial Surveys Give New Estimates for Orangutans in Sabah, Malaysia

PubMed Central

Gimenez, Olivier; Ambu, Laurentius; Ancrenaz, Karine; Andau, Patrick; Goossens, Benoît; Payne, John; Sawang, Azri; Tuuga, Augustine; Lackman-Ancrenaz, Isabelle

2005-01-01

Great apes are threatened with extinction, but precise information about the distribution and size of most populations is currently lacking. We conducted orangutan nest counts in the Malaysian state of Sabah (North Borneo), using a combination of ground and helicopter surveys, and provided a way to estimate the current distribution and size of the populations living throughout the entire state. We show that the number of nests detected during aerial surveys is directly related to the estimated true animal density and that a helicopter is an efficient tool to provide robust estimates of orangutan numbers. Our results reveal that with a total estimated population size of about 11,000 individuals, Sabah is one of the main strongholds for orangutans in North Borneo. More than 60% of orangutans living in the state occur outside protected areas, in production forests that have been through several rounds of logging extraction and are still exploited for timber. The role of exploited forests clearly merits further investigation for orangutan conservation in Sabah. PMID:15630475

Insights into Chronic Functional Movement Disorders: The Value of Qualitative Psychiatric Interviews.

PubMed

Epstein, Steven A; Maurer, Carine W; LaFaver, Kathrin; Ameli, Rezvan; Sinclair, Stephen; Hallett, Mark

Patients with functional movement disorders (FMDs) are commonly seen by neurologists and psychosomatic medicine psychiatrists. Research literature provides scant information about the subjective experiences of individuals with this often chronic problem. To enhance our understanding of psychologic aspects of FMDs by conducting qualitative interviews of research subjects. In total, 36 patients with FMDs were recruited from the Human Motor Control clinic at the National Institutes of Health. Each subject participated in a qualitative psychiatric interview and a structured diagnostic psychiatric interview. Of our 36 subjects, 28 had current or lifetime psychiatric disorders in addition to conversion disorder and 22 had current disorders. Qualitative interviews provided rich information on patients' understanding of their illnesses and impaired cognitive processing of emotions. Our study supports the addition of open-ended qualitative interviews to delineate emotional dynamics and conceptual frameworks among such patients. Exploratory interviews generate enhanced understanding of such complex patients, above and beyond that gained by assessing DSM diagnostic comorbidities. Copyright © 2016 The Academy of Psychosomatic Medicine. All rights reserved.

Distribution of Leptospira serogroups in cattle herds and dogs in France.

PubMed

Ayral, Florence C; Bicout, Dominique J; Pereira, Helena; Artois, Marc; Kodjo, Angeli

2014-10-01

A retrospective study was conducted to identify and describe the distribution pattern of Leptospira serogroups in domestic animals in France. The population consisted of cattle herds and dogs with clinically suspected leptospirosis that were tested at the "Laboratoire des Leptospires" between 2008 and 2011. The laboratory database was queried for records of cattle and dogs in which seroreactivity in Leptospira microagglutination tests was consistent with a recent or current infection, excluding vaccine serogroups in dogs. A total of 394 cattle herds and 232 dogs were diagnosed with clinical leptospirosis, and the results suggested infection by the Leptospira serogroup Australis in 43% and 63%, respectively; by the Leptospira serogroup Grippotyphosa in 17% and 9%, respectively; and by the Leptospira serogroup Sejroe in 33% and 6%, respectively. This inventory of infecting Leptospira serogroups revealed that current vaccines in France are not fully capable of preventing the clinical form of the disease. © The American Society of Tropical Medicine and Hygiene.

Pharmaceutical patent applications in freeze-drying.

PubMed

Ekenlebie, Edmond; Einfalt, Tomaž; Karytinos, Arianna Irò; Ingham, Andrew

2016-09-01

Injectable products are often the formulation of choice for new therapeutics; however, formulation in liquids often enhances degradation through hydrolysis. Thus, freeze-drying (lyophilization) is regularly used in pharmaceutical manufacture to reduce water activity. Here we examine its contribution to 'state of the art' and look at its future potential uses. A comprehensive search of patent databases was conducted to characterize the international patent landscape and trends in the use of freeze-drying. A total of 914 disclosures related to freeze-drying, lyophilization or drying of solid systems in pressures and temperatures equivalent to those of freeze-drying were considered over the period of 1992-2014. Current applications of sublimation technology were contrasted across two periods those with patents due to expire (1992-1993) and those currently filed. The number of freeze-drying technology patents has stabilized after initial activity across the biotechnology sector in 2011 and 2012. Alongside an increasing trend for patent submissions, freeze-drying submissions have slowed since 2002 and is indicative of a level of maturity.

Pulsed electromagnetic gas acceleration

NASA Technical Reports Server (NTRS)

Jahn, R. G.; Vonjaskowsky, W. F.; Clark, K. E.

1974-01-01

Detailed measurements of the axial velocity profile and electromagnetic structure of a high power, quasi-steady MPD discharge are used to formulate a gasdynamic model of the acceleration process. Conceptually dividing the accelerated plasma into an inner flow and an outer flow, it is found that more than two-thirds of the total power in the plasma is deposited in the inner flow, accelerating it to an exhaust velocity of 12.5 km/sec. The outer flow, which is accelerated to a velocity of only 6.2 km/sec, appears to provide a current conduction path between the inner flow and the anode. Related cathode studies have shown that the critical current for the onset of terminal voltage fluctuations, which was recently shown to be a function of the cathode area, appears to reach an asymptote for cathodes of very large surface area. Detailed floating potential measurements show that the fluctuations are confined to the vicinity of the cathode and hence reflect a cathode emission process rather than a fundamental limit on MPD performance.

Characterization of a novel 132-bp exon of the human maxi-K channel.

PubMed

Korovkina, V P; Fergus, D J; Holdiman, A J; England, S K

2001-07-01

The large-conductance Ca2+-activated voltage-dependent K+ channel (maxi-K channel) induces a significant repolarizing current that buffers cell excitability. This channel can derive its diversity by alternative splicing of its transcript-producing isoforms that differ in their sensitivity to voltage and intracellular Ca2+. We have identified a novel 132-bp exon of the maxi-K channel from human myometrial cells that encodes 44 amino acids within the first intracellular loop of the channel protein. Distribution analysis reveals that this exon is expressed predominantly in human smooth muscle tissues with the highest abundance in the uterus and aorta and resembles the previously reported distribution of the total maxi-K channel transcript. Single-channel K+ current measurements in fibroblasts transfected with the maxi-K channel containing this novel 132-bp exon demonstrate that the presence of this insert attenuates the sensitivity to voltage and intracellular Ca2+. Alternative splicing to introduce this 132-bp exon into the maxi-K channel may elicit another mode to modulate cell excitability.

PKA-induced internalization of slack KNa channels produces dorsal root ganglion neuron hyperexcitability.

PubMed

Nuwer, Megan O; Picchione, Kelly E; Bhattacharjee, Arin

2010-10-20

Inflammatory mediators through the activation of the protein kinase A (PKA) pathway sensitize primary afferent nociceptors to mechanical, thermal, and osmotic stimuli. However, it is unclear which ion conductances are responsible for PKA-induced nociceptor hyperexcitability. We have previously shown the abundant expression of Slack sodium-activated potassium (K(Na)) channels in nociceptive dorsal root ganglion (DRG) neurons. Here we show using cultured DRG neurons, that of the total potassium current, I(K), the K(Na) current is predominantly inhibited by PKA. We demonstrate that PKA modulation of K(Na) channels does not happen at the level of channel gating but arises from the internal trafficking of Slack channels from DRG membranes. Furthermore, we found that knocking down the Slack subunit by RNA interference causes a loss of firing accommodation analogous to that observed during PKA activation. Our data suggest that the change in nociceptive firing occurring during inflammation is the result of PKA-induced Slack channel trafficking.

Asthma, Airway Symptoms and Rhinitis in Office Workers in Malaysia: Associations with House Dust Mite (HDM) Allergy, Cat Allergy and Levels of House Dust Mite Allergens in Office Dust.

PubMed

Lim, Fang Lee; Hashim, Zailina; Than, Leslie Thian Lung; Md Said, Salmiah; Hisham Hashim, Jamal; Norbäck, Dan

2015-01-01

A prevalence study was conducted among office workers in Malaysia (N= 695). The aim of this study was to examine associations between asthma, airway symptoms, rhinitis and house dust mites (HDM) and cat allergy and HDM levels in office dust. Medical data was collected by a questionnaire. Skin prick tests were performed for HDM allergens (Dermatophagoides pteronyssinus, Dermatophagoides farinae) and cat allergen Felis domesticus. Indoor temperature and relative air humidity (RH) were measured in the offices and vacuumed dust samples were analyzed for HDM allergens. The prevalence of D. pteronyssinus, D. farinae and cat allergy were 50.3%, 49.0% and 25.5% respectively. Totally 9.6% had doctor-diagnosed asthma, 15.5% had current wheeze and 53.0% had current rhinitis. The Der p 1 (from D. pteronyssinus) and Der f 1 (from D. farinae) allergens levels in dust were 556 ng/g and 658 ng/g respectively. Statistical analysis was conducted by multilevel logistic regression, adjusting for age, gender, current smoking, HDM or cat allergy, home dampness and recent indoor painting at home. Office workers with HDM allergy had more wheeze (p= 0.035), any airway symptoms (p= 0.032), doctor-diagnosed asthma (p= 0.005), current asthma (p= 0.007), current rhinitis (p= 0.021) and rhinoconjuctivitis (p< 0.001). Cat allergy was associated with wheeze (p= 0.021), wheeze when not having a cold (p= 0.033), any airway symptoms (p= 0.034), doctor-diagnosed asthma (p= 0.010), current asthma (p= 0.020) and nasal allergy medication (p= 0.042). Der f 1 level in dust was associated with daytime breathlessness (p= 0.033) especially among those with HDM allergy. Der f 1 levels were correlated with indoor temperature (p< 0.001) and inversely correlated with RH (p< 0.001). In conclusion, HDM and cat allergies were common and independently associated with asthma, airway symptoms and rhinitis. Der f 1 allergen can be a risk factor for daytime breathlessness.

Asthma, Airway Symptoms and Rhinitis in Office Workers in Malaysia: Associations with House Dust Mite (HDM) Allergy, Cat Allergy and Levels of House Dust Mite Allergens in Office Dust

PubMed Central

Lim, Fang Lee; Hashim, Zailina; Than, Leslie Thian Lung; Md Said, Salmiah; Hisham Hashim, Jamal; Norbäck, Dan

2015-01-01

A prevalence study was conducted among office workers in Malaysia (N= 695). The aim of this study was to examine associations between asthma, airway symptoms, rhinitis and house dust mites (HDM) and cat allergy and HDM levels in office dust. Medical data was collected by a questionnaire. Skin prick tests were performed for HDM allergens (Dermatophagoides pteronyssinus, Dermatophagoides farinae) and cat allergen Felis domesticus. Indoor temperature and relative air humidity (RH) were measured in the offices and vacuumed dust samples were analyzed for HDM allergens. The prevalence of D. pteronyssinus, D. farinae and cat allergy were 50.3%, 49.0% and 25.5% respectively. Totally 9.6% had doctor-diagnosed asthma, 15.5% had current wheeze and 53.0% had current rhinitis. The Der p 1 (from D. pteronyssinus) and Der f 1 (from D. farinae) allergens levels in dust were 556 ng/g and 658 ng/g respectively. Statistical analysis was conducted by multilevel logistic regression, adjusting for age, gender, current smoking, HDM or cat allergy, home dampness and recent indoor painting at home. Office workers with HDM allergy had more wheeze (p= 0.035), any airway symptoms (p= 0.032), doctor-diagnosed asthma (p= 0.005), current asthma (p= 0.007), current rhinitis (p= 0.021) and rhinoconjuctivitis (p< 0.001). Cat allergy was associated with wheeze (p= 0.021), wheeze when not having a cold (p= 0.033), any airway symptoms (p= 0.034), doctor-diagnosed asthma (p= 0.010), current asthma (p= 0.020) and nasal allergy medication (p= 0.042). Der f 1 level in dust was associated with daytime breathlessness (p= 0.033) especially among those with HDM allergy. Der f 1 levels were correlated with indoor temperature (p< 0.001) and inversely correlated with RH (p< 0.001). In conclusion, HDM and cat allergies were common and independently associated with asthma, airway symptoms and rhinitis. Der f 1 allergen can be a risk factor for daytime breathlessness. PMID:25923543

Reverse leakage current characteristics of InGaN/GaN multiple quantum well ultraviolet/blue/green light-emitting diodes

NASA Astrophysics Data System (ADS)

Zhou, Shengjun; Lv, Jiajiang; Wu, Yini; Zhang, Yuan; Zheng, Chenju; Liu, Sheng

2018-05-01

We investigated the reverse leakage current characteristics of InGaN/GaN multiple quantum well (MQW) near-ultraviolet (NUV)/blue/green light-emitting diodes (LEDs). Experimental results showed that the NUV LED has the smallest reverse leakage current whereas the green LED has the largest. The reason is that the number of defects increases with increasing nominal indium content in InGaN/GaN MQWs. The mechanism of the reverse leakage current was analyzed by temperature-dependent current–voltage measurement and capacitance–voltage measurement. The reverse leakage currents of NUV/blue/green LEDs show similar conduction mechanisms: at low temperatures, the reverse leakage current of these LEDs is attributed to variable-range hopping (VRH) conduction; at high temperatures, the reverse leakage current of these LEDs is attributed to nearest-neighbor hopping (NNH) conduction, which is enhanced by the Poole–Frenkel effect.

Correlation analysis between the current fluctuation characteristics and the conductive filament morphology of HfO2-based memristor

NASA Astrophysics Data System (ADS)

Li, Yi; Yin, Kang-Sheng; Zhang, Mei-Yun; Cheng, Long; Lu, Ke; Long, Shi-Bing; Zhou, Yaxiong; Wang, Zhuorui; Xue, Kan-Hao; Liu, Ming; Miao, Xiang-Shui

2017-11-01

Memristors are attracting considerable interest for their prospective applications in nonvolatile memory, neuromorphic computing, and in-memory computing. However, the nature of resistance switching is still under debate, and current fluctuation in memristors is one of the critical concerns for stable performance. In this work, random telegraph noise (RTN) as the indication of current instabilities in distinct resistance states of the Pt/Ti/HfO2/W memristor is thoroughly investigated. Standard two-level digital-like RTN, multilevel current instabilities with non-correlation/correlation defects, and irreversible current transitions are observed and analyzed. The dependence of RTN on the resistance and read bias reveals that the current fluctuation depends strongly on the morphology and evolution of the conductive filament composed of oxygen vacancies. Our results link the current fluctuation behaviors to the evolution of the conductive filament and will guide continuous optimization of memristive devices.

Severity of eczema and mental health problems in Japanese schoolchildren: The ToMMo Child Health Study.

PubMed

Kuniyoshi, Yasutaka; Kikuya, Masahiro; Miyashita, Masako; Yamanaka, Chizuru; Ishikuro, Mami; Obara, Taku; Metoki, Hirohito; Nakaya, Naoki; Nagami, Fuji; Tomita, Hiroaki; Hozawa, Atsushi; Tsuji, Ichiro; Kure, Shigeo; Yaegashi, Nobuo; Yamamoto, Masayuki; Kuriyama, Shinichi

2018-04-13

The association between eczema and mental health problems in schoolchildren has been underexplored. We aimed to investigate this association with the validated questionnaires. Of 46,648 invited children, we analyzed 9954 (21.3%) in the 2nd to the 8th grades from the ToMMo Child Health Study conducted in 2014 and 2015, a cross-sectional survey in Miyagi Prefecture, Japan. We defined eczema status as "normal," "mild/moderate," or "severe," based on the presence of persistent flexural eczema and sleep disturbance, according to the International Study of Asthma and Allergies in Childhood (ISAAC) Eczema Symptom Questionnaire. Clinical ranges of Strengths and Difficulties Questionnaire (SDQ) total difficulties scores and four SDQ subcategories of emotional symptoms, conduct problems, hyperactivity/inattention, and peer problems were defined as scores ≥16, ≥5, ≥5, ≥7, and ≥5, respectively. The mean SDQ total difficulties score significantly increased as eczema status worsened (all P ≤ 0.004 for trend). The OR of scores in the clinical range for SDQ total difficulties were 1.51 (95% CI, 1.31-1.74) for mild/moderate eczema and 2.63 (95% CI, 1.91-3.63) for severe eczema (P < 0.001 for trend), adjusted for sex, school grade, current wheeze, and disaster-related factors, using normal eczema as a reference. The association between severity of eczema and four SDQ subcategories showed a similar trend (all P ≤ 0.017 for trend). We found a significant association between severity of eczema and mental health problems. The presence of eczema was associated with four SDQ subcategories. Copyright © 2018 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.

Reducing Potentially Avoidable Complications in Patients with Chronic Diseases: The Prometheus Payment Approach

PubMed Central

de Brantes, Francois; Rastogi, Amita; Painter, Michael

2010-01-01

Objective (or Study Question) To determine whether a new payment model can reduce current incidence of potentially avoidable complications (PACs) in patients with a chronic illness. Data Sources/Study Setting A claims database of 3.5 million commercially insured members under age 65. Study Design We analyzed the database using the Prometheus Payment model's analytical software for six chronic conditions to quantify total costs, proportion spent on PACs, and their variability across the United States. We conducted a literature review to determine the feasibility of reducing PACs. We estimated the financial impact on a prototypical practice if that practice received payments based on the Prometheus Payment model. Principal Findings We find that (1) PACs consume an average of 28.6 percent of costs for the six chronic conditions studied and vary significantly; (2) reducing PACs to the second decile level would save U.S.$116.7 million in this population; (3) current literature suggests that practices in certain settings could decrease PACs; and (4) using the Prometheus model could create a large potential incentive for a prototypical practice to reduce PACs. Conclusions By extrapolating these findings we conclude that costs might be reduced through payment reform efforts. A full extrapolation of these results, while speculative, suggests that total costs associated to the six chronic conditions studied could decrease by 3.8 percent. PMID:20662949

National workshop on core competencies for success in the veterinary profession.

PubMed

Lloyd, James W; King, Lonnie J; Klausner, Jeffrey S; Harris, Donna

2003-01-01

A workshop was designed to (1) present results of the Core Competencies for Veterinary Medicine project conducted by Personnel Decisions International (PDI); (2) discuss and analyze the implications of the PDI study results for academia, private practice, and industry; (3) identify actionable items-discuss opportunities and barriers; and (4) develop appropriate recommendations-devise specific actions for implementation as next steps. In total, 25 veterinary colleges were represented at the workshop and a total of 110 attendees participated, a broad cross-section of the veterinary profession (both academic and non-academic). Through an orchestrated combination of general sessions and facilitated, small group discussions, prioritized recommendations for implementation and initial action plans for next steps were developed. Recommendations included publicizing results of the PDI study, reconsidering current admissions policies and processes, evaluating the applicant pool and current recruitment programs, developing structured mentoring programs, enhancing DVM/VMD training programs, coordinating the development of continuing education programs, and overcoming existing barriers to change. Next steps should involve collaborative efforts across all sectors of the veterinary profession to develop plans for implementing the workshop's recommendations. Leadership for follow-up might reasonably come from the Association of American Veterinary Medical Colleges (AAVMC), the American Veterinary Medical Association (AVMA), and the American Animal Hospital Association (AAHA), either individually or collectively, through the National Commission on Veterinary Economic Issues (NCVEI). Partnerships with industry are also possible and should be strongly considered.

Lipid content and fatty acid composition of Porosira glacialis and Attheya longicornis in response to carbon dioxide (CO2) aeration.

PubMed

Artamonova, E Y; Vasskog, T; Eilertsen, H C

2017-01-01

In the current study two novel psychrophilic diatoms Porosira glacialis and Attheya longicornis were tested for suitability to CO2 mitigation coupled with production of the physiologically requisite omega- 3 fatty acids. This study is in line with the worldwide conducted research aimed at applying biorefinery concept to heavy polluting industries. Since the production of algal high value compounds, i.e. essential fatty acids, relies on utilization of residual CO2 emissions coming from industry, the costs of such production maybe substantially reduced. Besides, the ecological benefits of the biorefinery concept being implemented are obvious, since CO2 is one of the major greenhouse gases. The current research has shown that one of the tested microalgal species, the diatom P. glacialis showed good tolerance to high (20-25%) levels of CO2 and maintained growth rates comparable to controls. The total lipid content in the CO2 aerated culture increased from 8.91 to 10.57% in cell dry mass. Additionally, the content of docosahexaenoic acid (DHA) increased from 3.90 to 5.75%, while the concentration of eicosapentaenoic acid (EPA) decreased from 26.59 to 23.66%. In contrast, A. longicornis did not demonstrate any significant increase in total lipid content. Besides, its growth was hampered by high levels of CO2 aeration.

Electrolytic treatment of Standard Malaysian Rubber process wastewater.

PubMed

Vijayaraghavan, Krishnan; Ahmad, Desa; Yazid, Ahmad Yuzri Ahmad

2008-01-31

A new method of Standard Malaysian Rubber (SMR) process wastewater treatment was developed based on in situ hypochlorous acid generation. The hypochlorous acid was generated in an undivided electrolytic cell consisting of two sets of graphite as anode and stainless sheets as cathode. The generated hypochlorous acid served as an oxidizing agent to destroy the organic matter present in the SMR wastewater. For an influent COD concentration of 2960 mg/L at an initial pH 4.5+/-0.1, current density 74.5 mA/cm(2), sodium chloride content 3% and electrolysis period of 75 min, resulted in the following residual values pH 7.5, COD 87 mg/L, BOD(5) 60 mg/L, TOC 65 mg/L, total chlorine 146 mg/L, turbidity 7 NTU and temperature 48 degrees C, respectively. In the case of 2% sodium chloride as an electrolyte for the above said operating condition resulted in the following values namely: pH 7.2, COD 165 mg/L, BOD(5) 105 mg/L, TOC 120 mg/L, total chlorine 120 mg/L, turbidity 27 NTU and temperature 53 degrees C, respectively. The energy requirement were found to be 30 and 46 Wh/L, while treating 24 L of SMR wastewater at 2 and 3% sodium chloride concentration at a current density 74.5 mA/cm(2). The observed energy difference was due to the improved conductivity at high sodium chloride content.

Which primary total knee replacement? A review of currently available TKR in the United Kingdom.

PubMed Central

Liow, R. Y.; Murray, D. W.

1997-01-01

Comparative information on total knee replacements (TKRs) is not readily available. With the help of implant manufacturers and distributors, we have compiled a list of TKRs on the market in the UK and summarised the information about these implants in a table. There are 37 different TKRs, marketed by 14 companies; 54% have been introduced since 1990. The number of different implants is increasing. At least eight designs have undergone major modifications, while many have had minor alterations. Of the TKRs on the market, 60% are modular. Some 54% of TKRs have no published results in peer-reviewed journals; only one of the four most widely used prostheses has published survival figures. New and modified implants are introduced without clinical evidence of their superiority over other available designs. Published results in peer-reviewed journals are currently the best evidence available on the reliability of an implant. When selecting an implant, surgeons should be aware if the prosthesis has any such results, the length of the follow-up, and the survival rates that are achieved. More detailed interpretation is difficult because of the different combinations used in modular implants and because of the frequent modification of existing designs. Properly conducted long-term clinical trials should be encouraged as they are the only means of evaluating new designs. PMID:9326124

77 FR 64709 - Airworthiness Directives; MD Helicopters, Inc.

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-23

... visual inspection, and if necessary, an eddy current inspection of the main rotor lower hub assembly... specifies an initial 100-hour and recurring 300-hour visual and eddy current inspections of the lower hub... a total cost per helicopter of $85 and a total cost of $1,020 for the fleet. Eddy current inspecting...