Assessment of a field-aligned ICRF antenna

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

Wukitch, S. J.; Brunner, D.; Ennever, P.

Impurity contamination and localized heat loads associated with ion cyclotron range of frequency (ICRF) antenna operation are among the most challenging issues for ICRF utilization.. Another challenge is maintaining maximum coupled power through plasma variations including edge localized modes (ELMs) and confinement transitions. Here, we report on an experimental assessment of a field aligned (FA) antenna with respect to impurity contamination, impurity sources, RF enhanced heat flux and load tolerance. In addition, we compare the modification of the scrape of layer (SOL) plasma potential of the FA antenna to a conventional, toroidally aligned (TA) antenna, in order to explore themore » underlying physics governing impurity contamination linked to ICRF heating. The FA antenna is a 4-strap ICRF antenna where the current straps and antenna enclosure sides are perpendicular to and the Faraday screen rods are parallel to the total magnetic field. In principle, alignment with respect to the total magnetic field minimizes integrated E∥ (electric field along a magnetic field line) via symmetry. Consistent with expectations, we observed that the impurity contamination and impurity source at the FA antenna are reduced compared to the TA antenna. In both L and H-mode discharges, the radiated power is 20–30% lower for a FA-antenna heated discharge than a discharge heated with the TA-antennas. Further we observe that the fraction of RF energy deposited upon the antenna is less than 0.4 % of the total injected RF energy in dipole phasing. The total deposited energy increases significantly when the FA antenna is operated in monopole phasing. The FA antenna also exhibits an unexpected load tolerance for ELMs and confinement transitions compared to the TA antennas. However, inconsistent with expectations, we observe RF induced plasma potentials to be nearly identical for FA and TA antennas when operated in dipole phasing. In monopole phasing, the FA antenna has the highest

Recent Heating and Current Drive results on JET

NASA Astrophysics Data System (ADS)

Tuccillo, A. A.; Baranov, Y.; Barbato, E.; Bibet, Ph.; Castaldo, C.; Cesario, R.; Cocilovo, V.; Crisanti, F.; De Angelis, R.; Ekedahl, A. C.; Figueiredo, A.; Graham, M.; Granucci, G.; Hartmann, D.; Heikkinen, J.; Hellsten, T.; Imbeaux, F.; Jones, T. T. H.; Johnson, T.; Kirov, K. V.; Lamalle, P.; Laxaback, M.; Leuterer, F.; Litaudon, X.; Maget, P.; Mailloux, J.; Mantsinen, M. J.; Mayoral, M. L.; Meo, F.; Monakhov, I.; Nguyen, F.; Noterdaeme, J.-M.; Pericoli-Ridolfini, V.; Podda, S.; Panaccione, L.; Righi, E.; Rimini, F.; Sarazin, Y.; Sibley, A.; Staebler, A.; Tala, T.; Van Eester, D.

2001-10-01

An overview is presented of the results obtained on JET by the Heating and Current Drive Task Force (TF-H) in the period May 2000—March 2001. A strongly improved Lower Hybrid (LH) coupling was achieved by optimizing the plasma shape and by controlling the local edge density via the injection of CD4. Up to 4 MW have been coupled in type III ELMy H-mode and/or on Internal Transport Barrier (ITB) plasmas with reflection coefficients as low as 4%. Long lasting quasi steady-state ITBs have been obtained by adding the LH current to the bootstrap and beam driven components. Furthermore the use of LH in the pre-heat phase results in electron temperature in excess of 10 keV, deep negative magnetic shear and strongly reduced power threshold for ITB formation. Preliminary results on ICRF coupling are reported including the effect of CD4 injection and the commissioning of the wide band matching system on ELMy plasmas. IC CD scenarios have been studied in H and 3He minority and used to modify the stability of the sawtooth to influence the formation of seed islands for the appearance of NTM. Up to 3 MW of IC power was coupled in the high magnetic field fast wave CD scenario. Preliminary MSE measurements indicate differences in the current profiles between -90° and +90° phasing. Careful measurements of the toroidal rotation, in plasmas heated by ICRF only show some dependence on the position of the resonance layer. Finally the use of ICRF minority heating under real-time control, in response to measured plasma parameters to simulate the effect of alpha particles, is presented. ICRF heating results in ITER non-activated scenarios are reported in a companion paper.

Experimental pathways to understand and avoid high-Z impurity contamination from ICRF heating in tokamaks

NASA Astrophysics Data System (ADS)

Reinke, Matthew

2016-10-01

Recent results from Alcator C-Mod and JET demonstrate progress in understanding and mitigating core high-Z impurity contamination linked to ICRF heating in tokamaks with high-Z PFCs. Theory has identified two likely mechanisms: impurity sources due to sputtering enhanced by RF-rectified sheaths and greater cross-field SOL transport due to ExB convective cells. New experiments on Alcator C-Mod and JET demonstrate convective cell transport is likely a sub-dominant effect, despite directly observing ExB flows from rectified RF fields on C-Mod. Trace N2 introduced in the far SOL on field lines connected to and well away from an active ICRF antenna result in similar levels of core nitrogen, indicating local RF-driven transport is weak. This suggests the core high-Z density, nZ,core, is determined by sheath-induced sputtering and RF-independent SOL transport, allowing further reductions through antenna design. ICRF heating on C-Mod uses a unique, field aligned (FAA) and a pair of conventional, toroidally aligned (TAA) antennas. The FAA is designed to reduce rectified voltages relative to the TAA, and the impact of sheath-induced sputtering is explored by observing nZ,core while varying the TAA/FAA heating mix. A reduction of approximately 50% in core high-Z content is seen in L-modes when using the FAA and high-Z sources at the antenna limiter are effectively eliminated, indicating the remaining RF-driven source is away from the limiter. A drop in nZ,core may also be realized by locating the RF antenna on the inboard side where SOL transport aids impurity screening. New C-Mod experiments demonstrate up to a factor of 5 reduction in core nitrogen when N2 is injected on the high-field side as compared to low-field side impurity fueling. Varying the magnetic topology helps to elucidate the SOL transport physics responsible, laying a physics basis for inboard RF antenna placement. This work is supported by U.S. DOE Award DE-FC02-99ER54512, using Alcator C-Mod and carried out

Recent ICRF coupling experiments on EAST

NASA Astrophysics Data System (ADS)

Yuqing, YANG; Xinjun, ZHANG; Yanping, ZHAO; Chengming, QIN; Yan, CHENG; Yuzhou, MAO; Hua, YANG; Jianhua, WANG; Shuai, YUAN; Lei, WANG; Songqing, JU; Gen, CHEN; Xu, DENG; Kai, ZHANG; Baonian, WAN; Jiangang, LI; Yuntao, SONG; Xianzu, GONG; Jinping, QIAN; Tao, ZHANG

2018-04-01

Recent ion cyclotron resonance frequency (ICRF) coupling experiments for optimizing ICRF heating in high power discharge were performed on EAST. The coupling experiments were focus on antenna phasing and gas puffing, which were performed separately on two ports of the ion cyclotron resonance heating (ICRH) system of EAST. The antenna phasing was performed on the I-port antenna, which consists of four toroidally spaced radiating straps operating in multiple phasing cases; the coupling performance was better under low wave number | {k}\\parallel | (ranging from 4.5 to 6.5). By fuelling the plasma from gas injectors, placed as uniformly spaced array from top to bottom at each side limiter of the B-port antenna, which works in dipole phasing, the coupling resistance of the B-port antenna increased obviously. Furthermore, the coupling resistance of the I-port antenna was insensitive to a smaller rate of gas puffing but when the gas injection rate was more than a certain value (>1021s‑1), a sharp increase in the coupling resistance of the I-port antenna occurred, which was mainly caused by the toroidal asymmetric boundary density arising from gas puffing. A more specific analysis is given in the paper.

ICRF-Induced Changes in Floating Potential and Ion Saturation Current in the EAST Divertor

NASA Astrophysics Data System (ADS)

Perkins, Rory; Hosea, Joel; Taylor, Gary; Bertelli, Nicola; Kramer, Gerrit; Qin, Chengming; Wang, Liang; Yang, Jichan; Zhang, Xinjun

2017-10-01

Injection of waves in the ion cyclotron range of frequencies (ICRF) into a tokamak can potentially raise the plasma potential via RF rectification. Probes are affected both by changes in plasma potential and also by RF-averaging of the probe characteristic, with the latter tending to drop the floating potential. We present the effect of ICRF heating on divertor Langmuir probes in the EAST experiment. Over a scan of the outer gap, probes connected to the antennas have increases in floating potential with ICRF, but probes in between the outer-vessel strike point and flux surface tangent to the antenna have decreased floating potential. This behaviour is investigated using field-line mapping. Preliminary results show that mdiplane gas puffing can suppress the strong influence of ICRF on the probes' floating potential.

Effects of ICRF power on SOL density profiles and LH coupling during simultaneous LH and ICRF operation on Alcator C-Mod

NASA Astrophysics Data System (ADS)

Lau, C.; Lin, Y.; Wallace, G.; Wukitch, S. J.; Hanson, G. R.; Labombard, B.; Ochoukov, R.; Shiraiwa, S.; Terry, J.

2013-09-01

A dedicated experiment during simultaneous lower hybrid (LH) and ion cyclotron range-of-frequencies (ICRF) operations is carried out to evaluate and understand the effects of ICRF power on the scrape-off-layer (SOL) density profiles and on the resultant LH coupling for a wide range of plasma parameters on Alcator C-Mod. Operation of the LH launcher with the adjacent ICRF antenna significantly degrades LH coupling while operation with the ICRF antenna that is not magnetically connected to the LH launcher minimally affects LH coupling. An X-mode reflectometer system at three poloidal locations adjacent to the LH launcher and a visible video camera imaging the LH launcher are used to measure local SOL density profile and emissivity modifications with the application of LH and LH + ICRF power. These measurements confirm that the density in front of the LH launcher depends strongly on the magnetic field line mapping of the active ICRF antenna. Reflectometer measurements also observe both ICRF-driven and LH-driven poloidal density profile asymmetries, especially a strong density depletion at certain poloidal locations in front of the LH launcher during operation with a magnetically connected ICRF antenna. The results indicate that understanding both LH-driven flows and ICRF sheath driven flows may be necessary to understand the observed density profile modifications and LH coupling results during simultaneous LH + ICRF operation.

Aspects of ICRF-3

NASA Astrophysics Data System (ADS)

Ma, Chopo; MacMillan, Daniel; Le Bail, Karine; Gordon, David

2016-12-01

The Second Realization of the International Celestial Reference Frame (ICRF2) used dual-frequency VLBI data acquired for geodetic and astrometric purposes from 1979-2009 by organizations coordinated by the IVS and various precursor networks. Since 2009 the data set has been significantly broadened, especially by observations in the southern hemisphere. While the new southern data have ameliorated the north/south imbalance of observations, they appear to produce a systematic zonal declination change in the catalog positions. Over the 35 years of the ICRF data set the effect of galactic aberration may be significant. Geophysical and tropospheric models also may affect the source positions. All these effects need to be addressed in preparation for ICRF-3.

Recent progress on improving ICRF coupling and reducing RF-specific impurities in ASDEX Upgrade

NASA Astrophysics Data System (ADS)

Zhang, Wei; Bobkov, Volodymyr; Noterdaeme, Jean-Marie; Tierens, Wouter; Aguiam, Diogo; Bilato, Roberto; Coster, David; Colas, Laurent; Crombé, Kristel; Fuenfgelder, Helmut; Faugel, Helmut; Feng, Yuhe; Jacquot, Jonathan; Jacquet, Philippe; Kallenbach, Arne; Kostic, Ana; Lunt, Tilmann; Maggiora, Riccardo; Ochoukov, Roman; Silva, Antonio; Suárez, Guillermo; Tuccilo, Angelo A.; Tudisco, Onofrio; Usoltceva, Mariia; Van Eester, Dirk; Wang, Yongsheng; Yang, Qingxi

2017-10-01

The recent scientific research on ASDEX Upgrade (AUG) has greatly advanced solutions to two issues of Radio Frequency (RF) heating in the Ion Cyclotron Range of Frequencies (ICRF): (a) the coupling of ICRF power to the plasma is significantly improved by density tailoring with local gas puffing; (b) the release of RF-specific impurities is significantly reduced by minimizing the RF near field with 3-strap antennas. This paper summarizes the applied methods and reviews the associated achievements.

Estimation of sheath potentials in front of ASDEX upgrade ICRF antenna with SSWICH asymptotic code

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

Křivská, A., E-mail: alena.krivska@rma.ac.be; Bobkov, V.; Jacquot, J.

Multi-megawatt Ion Cyclotron Range of Frequencies (ICRF) heating became problematic in ASDEX Upgrade (AUG) tokamak after coating of ICRF antenna limiters and other plasma facing components by tungsten. Strong impurity influx was indeed produced at levels of injected power markedly lower than in the previous experiments. It is assumed that the impurity production is mainly driven by parallel component of Radio-Frequency (RF) antenna electric near-field E// that is rectified in sheaths. In this contribution we estimate poloidal distribution of sheath Direct Current (DC) potential in front of the ICRF antenna and simulate its relative variations over the parametric scans performedmore » during experiments, trying to reproduce some of the experimental observations. In addition, relative comparison between two types of AUG ICRF antenna configurations, used for experiments in 2014, has been performed. For this purpose we use the Torino Polytechnic Ion Cyclotron Antenna (TOPICA) code and asymptotic version of the Self-consistent Sheaths and Waves for Ion Cyclotron Heating (SSWICH) code. Further, we investigate correlation between amplitudes of the calculated oscillating sheath voltages and the E// fields computed at the lateral side of the antenna box, in relation with a heuristic antenna design strategy at IPP Garching to mitigate RF sheaths.« less

The Role of Combined ICRF and NBI Heating in JET Hybrid Plasmas in Quest for High D-T Fusion Yield

NASA Astrophysics Data System (ADS)

Mantsinen, Mervi; Challis, Clive; Frigione, Domenico; Graves, Jonathan; Hobirk, Joerg; Belonohy, Eva; Czarnecka, Agata; Eriksson, Jacob; Gallart, Dani; Goniche, Marc; Hellesen, Carl; Jacquet, Philippe; Joffrin, Emmanuel; King, Damian; Krawczyk, Natalia; Lennholm, Morten; Lerche, Ernesto; Pawelec, Ewa; Sips, George; Solano, Emilia R.; Tsalas, Maximos; Valisa, Marco

2017-10-01

Combined ICRF and NBI heating played a key role in achieving the world-record fusion yield in the first deuterium-tritium campaign at the JET tokamak in 1997. The current plans for JET include new experiments with deuterium-tritium (D-T) plasmas with more ITER-like conditions given the recently installed ITER-like wall (ILW). In the 2015-2016 campaigns, significant efforts have been devoted to the development of high-performance plasma scenarios compatible with ILW in preparation of the forthcoming D-T campaign. Good progress was made in both the inductive (baseline) and the hybrid scenario: a new record JET ILW fusion yield with a significantly extended duration of the high-performance phase was achieved. This paper reports on the progress with the hybrid scenario which is a candidate for ITER longpulse operation (˜1000 s) thanks to its improved normalized confinement, reduced plasma current and higher plasma beta with respect to the ITER reference baseline scenario. The combined NBI+ICRF power in the hybrid scenario was increased to 33 MW and the record fusion yield, averaged over 100 ms, to 2.9x1016 neutrons/s from the 2014 ILW fusion record of 2.3x1016 neutrons/s. Impurity control with ICRF waves was one of the key means for extending the duration of the high-performance phase. The main results are reviewed covering both key core and edge plasma issues.

Considerations for ICRF-3

NASA Astrophysics Data System (ADS)

Ma, Chopo; MacMillan, Daniel; Gordon, David

2015-08-01

The Second Realization of the International Celestial Reference Frame (ICRF) used dual-frequency VLBI data acquired for geodetic and astrometric purposes from 1979-2009 by organizations now coordinated by the International VLBI Service for Geodesy and Astrometry (IVS) and analyzed according to the Conventions of the International Earth Rotation and Reference Systems Service (IERS). Since 2009 the data set has been significantly broadened, especially by observations in the Southern Hemisphere, and modeling of astronomical, geophysical and tropospheric effects has progressed. The new southern data appear to cause a systematic zonal declination change in the catalog positions. Over the three decades of the ICRF data set the effect of galactic aberration may be significant. Geophysical and tropospheric models also may affect the source positions. All these effects need to be addressed in preparation for ICRF-3.

ICRF fast wave current drive and mode conversion current drive in EAST tokamak

NASA Astrophysics Data System (ADS)

Yin, L.; Yang, C.; Gong, X. Y.; Lu, X. Q.; Du, D.; Chen, Y.

2017-10-01

Fast wave in the ion-cyclotron resonance frequency (ICRF) range is a promising candidate for non-inductive current drive (CD), which is essential for long pulse and high performance operation of tokamaks. A numerical study on the ICRF fast wave current drive (FWCD) and mode-conversion current drive (MCCD) in the Experimental Advanced Superconducting Tokamak (EAST) is carried out by means of the coupled full wave and Ehst-Karney parameterization methods. The results show that FWCD efficiency is notable in two frequency regimes, i.e., f ≥ 85 MHz and f = 50-65 MHz, where ion cyclotron absorption is effectively avoided, and the maximum on-axis driven current per unit power can reach 120 kA/MW. The sensitivity of the CD efficiency to the minority ion concentration is confirmed, owing to fast wave mode conversion, and the peak MCCD efficiency is reached for 22% minority-ion concentration. The effects of the wave-launch position and the toroidal wavenumber on the efficiency of current drive are also investigated.

Towards a Future ICRF Realization

NASA Technical Reports Server (NTRS)

Ma, Chopo; Gordon, D.; MacMillan, D.; Petrov, L.; Smith, David E. (Technical Monitor)

2001-01-01

The data and analysis for the ICRF were completed in 1995 to define a frame to which the Hipparcos optical catalog could be fixed. Additional observations on most of the 608 sources in the overall ICRF catalog have been acquired using a small portion of geodetic observing time as well as astrometric sessions concentrating on the southern hemisphere. Positions of new sources have been determined, including approx.1200 from a VLBA phase calibrator survey. A future ICRF realization will require improved geophysical modeling, sophisticated treatment of position variations and/or source structure, optimized data selection and weighting, and reidentification of defining sources. The motivation for the next realization could be significant improvement in accuracy and density or preparation for optical extragalactic catalogs with microarcsecond precision.

Towards a Future ICRF Realization

NASA Technical Reports Server (NTRS)

Ma, Chopo; Gordon, David; MacMillan, Daniel; Petrov, Leonid

2002-01-01

The data and analysis for the ICRF were completed in 1995 to define a frame to which the Hipparcos optical catalog could be fixed. Additional observations on most of the 608 sources in the overall ICRF catalog have been acquired using a small portion of geodetic observing time as well as astrometric sessions concentrating on the Southern Hemisphere. Positions of new sources have been determined, including approximately 1200 from a VLBA phase calibrator survey. A future ICRF realization will require improved geophysical modeling, sophisticated treatment of position variations and/or source structure, optimized data selection and weighting, and re-identification of defining sources. The motivation for the next realization could be significant improvement in accuracy and density or preparation for optical extragalactic catalogs with microarcsecond precision.

ICRF-187 in clinical oncology.

PubMed

Poster, D S; Penta, J S; Bruno, S; Macdonald, J S

1981-01-01

Although the mechanism of action of ICRF-159 and 187 has not been clearly defined, it is evident from both preclinical and early clinical studies that these compounds are of interest. There are three distinct characteristics of these ICRF compounds that deserve careful clinical evaluation. First, these drugs are apparently alkylating agents with modest, predictable and noncumulative bone marrow toxicity that makes them good potential candidates for combination chemotherapy regimens. The second characteristic that should be investigated is the suggestion that combination of ICRF-187 with an anthracycline may ameliorate the cardiac toxicity of the latter. The third factor in the preclinical evaluation of the bis-diketopiperazines that may have clinical application is the evidence that suggests that these drugs have an antimetastatic effect.

Refinement of the ICRF

NASA Technical Reports Server (NTRS)

Ma, Chopo

2004-01-01

Since the ICRF was generated in 1995, VLBI modeling and estimation, data quality: source position stability analysis, and supporting observational programs have improved markedly. There are developing and potential applications in the areas of space navigation Earth orientation monitoring and optical astrometry from space that would benefit from a refined ICRF with enhanced accuracy, stability and spatial distribution. The convergence of analysis, focused observations, and astrometric needs should drive the production of a new realization in the next few years.

Extending the ICRF to Higher Radio Frequencies

NASA Technical Reports Server (NTRS)

Jacobs, C. S.; Jones, D. L.; Lanyi, G. E.; Lowe, S. T.; Naudet, C. J.; Resch, G. M.; Steppe, J. A.; Zhang, L. D.; Ulvestad, J. S.; Taylor, G. B.

2002-01-01

The ICRF forms the basis for all astrometry including use as the inertial coordinate system for navigating deep space missions. This frame was defined using S/X-band observations over the past 20+ years. In January 2002, the VLBA approved our proposal for observing time to extend the ICRF to K-band (24 GHz) and Q-band (43 GHz). The first step will be observations at K- and Q-bands on a subset of ICRF sources. Eventually, K- and Q-band multi-epoch observations will be used to estimate positions, flux density and source structure for a large fraction of the current S/X-band ICRF source list. This work will benefit the radio astronomy community by extending the VLBA calibrator list at these bands. In the longer term, we would also like to extend the ICRF to Ka-band (32 GHz). A celestial reference frame will be needed at this frequency to support deep space navigation. A navigation demonstration is being considered for NASA's Mars 2005 mission. The initial K- and Q-band work will serve to identify candidate sources at Ka-band for use with that mission.

Toward the ICRF3: Astrometric Comparison of the USNO 2016A VLBI Solution with ICRF2 and Gaia DR1

NASA Astrophysics Data System (ADS)

Frouard, Julien; Johnson, Megan C.; Fey, Alan; Makarov, Valeri V.; Dorland, Bryan N.

2018-06-01

The VLBI USNO 2016A (U16A) solution is part of a work-in-progress effort by USNO toward the preparation of the ICRF3. Most of the astrometric improvement with respect to the ICRF2 is due to the re-observation of the VCS sources. Our objective in this paper is to assess U16A’s astrometry. A comparison with ICRF2 shows statistically significant offsets of size 0.1 mas between the two solutions. While Gaia DR1 positions are not precise enough to resolve these offsets, they are found to be significantly closer to U16A than ICRF2. In particular, the trend for typically larger errors for southern sources in VLBI solutions is decreased in U16A. Overall, the VLBI-Gaia offsets are reduced by 21%. The U16A list includes 718 sources not previously included in ICRF2. Twenty of those new sources have statistically significant radio-optical offsets. In two-thirds of the cases, these offsets can be explained from PanSTARRS images.

Uses of the ICRF and implications for future VLBI

NASA Technical Reports Server (NTRS)

Ma, Chopo

2006-01-01

Since its inception on 1 Jan 1998, the fundamental ICRF has been set by the VLBI positions of 212 "defining" extragalactic radio sources. In all there are approx.3000 sources with usefully accurate (< few mas) positions consistent with the ICRF. The uses of the ICRF include fundamental astrometry, monitoring of Earth orientation, and spacecraft navigation. For fundamental astrometry, stability and accuracy are most important, and realizations at different frequencies must be in proper registration. However, there is no preferred frequency, and the GAIA mission has the potential for an optical ICRF with 500,000 objects at the 50 microarcsec level some time after the planned 2011 launch. The radio ICRF should be properly prepared for a transition to assure long term stability and consistency. Earth orientation monitoring requires objects attached to the solid Earth, and VLBI will continue to be the fundamental technique. For this purpose it is essential that the new VLBI stations contemplated in the VLBI20l0 report be capable of observing a sufficiently large and well-distributed set of stable sources, and identifying these sources is an on-going effort. Spacecraft navigation by differential VLBI is planned using the Ka-band telemetry signal, and work has begun towards an ICRF realization suitable for this purpose. The balancing of different needs related to the VLBI ICRF will be discussed.

International Celestial Reference Frame (ICRF): mantenimiento y extensión

NASA Astrophysics Data System (ADS)

Ma, C.; Arias, E. F.; Eubanks, T.; Fey, A. L.; Gontier, A.-M.; Jacobs, C. S.; Sovers, O. J.; Archinal, B. A.; Charlot, P.

A partir de enero de 1998 el sistema de referencia celeste convencional está representado por el International Celestial Reference System (ICRS) y materializado a través de las coordenadas VLBI del conjunto de radiofuentes extragalácticas que conforman el International Celestial Reference Frame (ICRF). La primera realización del ICRF, fue elaborada en 1995 por un grupo de expertos designado por la IAU, la que encomendó al International Earth Rotation Service el mantenimiento del ICRS, del ICRF y del vínculo con marcos de referencia en otras frecuencias. Una primera extensión del ICRF se realizó entre abril y junio de 1999, con el objetivo primario de proveer posiciones de radiofuentes extragalácticas observadas a partir de julio de 1995 y de mejorar las posiciones de las fuentes ``candidatas" con la inclusión de observaciones adicionales. Objetivos secundarios fueron monitorear a las radiofuentes para verificar que siguen siendo adecuadas para realizar al ICRF y mejorar las técnicas de análisis de datos. Como resultado del nuevo análisis se obtuvo una solución a partir de la cual se construyó la primera extensión del ICRF, denominada ICRF - Ext.1. Ella representa al ICRS, sus fuentes de definición se mantienen con las mismas posiciones y errores que en la primera realización del ICRF; las demás radiofuentes tienen coordenadas mejor determinadas que en ICRF; el marco de referencia se densificó con el agregado de 59 nuevas radiofuentes.

Development of plasma sources for ICRF heating experiment in KMAX mirror device

NASA Astrophysics Data System (ADS)

Sun, Xuan; Liu, Ming; Yi, Hongshen; Lin, Munan; Shi, Peiyun

2016-10-01

KMAX, Keda Mirror with AXisymmeticity, is a tandem mirror machine with a length of 10 meters and diameters of 1.2 meters in the central cell and 0.3 meters in the mirror throat. In the past experiments, the plasma was generated by helicon wave launched from the west end. We obtained the blue core mode in argon discharge, however, it cannot provide sufficient plasma for hydrogen discharge, which is at least 1012 cm-3 required for effective ICRF heating. Several attempts have thus been tried or under design to increase the central cell's plasma density: (1) a washer gun with aperture of 1cm has been successfully tested, and a plasma density of 1013 cm-3 was achieved in the west cell near the gun, however, the plasma is only 1011 cm-3 in the central cell possible due to the mirror trapping and/or neutral quenching effect (2) a larger washer gun with aperture of 2.5 cm and a higher power capacitor bank are being assembled in order to generate more plasmas. In addition, how to mitigate the neutrals is under consideration (3) A hot cathode is been designed and will be tested in combination with plasma gun or alone. Preliminary results from those plasma sources will be presented and discussed.

The Second International Celestial Reference Frame (ICRF2)

NASA Technical Reports Server (NTRS)

Ma, Chopo

2010-01-01

The ICRF2 catalog was constructed by the IERS/IVS Working Group with oversight by the IAU Working Group. Derived using data from August 1979 through March 2009, it is a great improvement over the original ICRF with 3414 extragalactic radio source positions, a noise floor of 40 microarcsec, and axis stability of 10 microarcsec. Significant refinements were made in the selection of defining sources, modeling, and the integration of CRF, TRF, and EOP. The adoption of the ICRF2 was approved by the IAU in Resolution B3 at the XXVII IAU General Assembly and became effective 1 January 2010.

VizieR Online Data Catalog: VLBI ICRF2 (Fey+, 2015)

NASA Astrophysics Data System (ADS)

Fey, A. L.; Gordon, D.; Jacobs, C. S.; Ma, C.; Gaume, R. A.; Arias, E. F.; Bianco, G.; Boboltz, D. A.; Bockmann, S.; Bolotin, S.; Charlot, P.; Collioud, A.; Engelhardt, G.; Gipson, J.; Gontier, A.-M.; Heinkelmann, R.; Kurdubov, S.; Lambert, S.; Lytvyn, S.; MacMillan, D. S.; Malkin, Z.; Nothnagel, A.; Ojha, R.; Skurikhina, E.; Sokolova, J.; Souchay, J.; Sovers, O. J.; Tesmer, V.; Titov, O.; Wang, G.; Zharov, V.

2016-01-01

We present the second realization of the International Celestial Reference Frame (ICRF2) at radio wavelengths using nearly 30 years of Very Long Baseline Interferometry observations. The earliest observations used are from 1979 August and the latest are from 2009 March. ICRF2 consists of accurate positions of 295 new "defining" sources and positions of 3119 additional compact radio sources to densify the frame. ICRF2 has more than 5 times as many sources as ICRF1 (Ma et al. 1997, cat. I/251), is roughly 5-6 times more accurate, and is nearly twice as stable in the orientation of its axes. (3 data files).

Use of /sup 3/He/sup + +/ ICRF minority heating to simulate alpha particle heating

DOEpatents

Post, D.E. Jr.; Hwang, D.Q.; Hovey, J.

1983-11-16

It is an object of the present invention to provide a better understanding of alpha particle behavior in a magnetically confined, energetic plasma. Another object of the present invention is to provide an improved means and method for studying and measuring the energy distribution of heated alpha particles in a confined plasma. Yet another object of the present invention is to permit detailed analysis of energetic alpha particle behavior in a magnetically confined plasma for use in near term fusion reactor experiments. A still further object of the present invention is to simulate energetic alpha particle behavior in a deuterium-tritium plasma confined in a fusion reactor without producing the neutron activation associated with the thus produced alpha particles.

Spectral Calculation of ICRF Wave Propagation and Heating in 2-D Using Massively Parallel Computers

NASA Astrophysics Data System (ADS)

Jaeger, E. F.; D'Azevedo, E.; Berry, L. A.; Carter, M. D.; Batchelor, D. B.

2000-10-01

Spectral calculations of ICRF wave propagation in plasmas have the natural advantage that they require no assumption regarding the smallness of the ion Larmor radius ρ relative to wavelength λ. Results are therefore applicable to all orders in k_bot ρ where k_bot = 2π/λ. But because all modes in the spectral representation are coupled, the solution requires inversion of a large dense matrix. In contrast, finite difference algorithms involve only matrices that are sparse and banded. Thus, spectral calculations of wave propagation and heating in tokamak plasmas have so far been limited to 1-D. In this paper, we extend the spectral method to 2-D by taking advantage of new matrix inversion techniques that utilize massively parallel computers. By spreading the dense matrix over 576 processors on the ORNL IBM RS/6000 SP supercomputer, we are able to solve up to 120,000 coupled complex equations requiring 230 GBytes of memory and achieving over 500 Gflops/sec. Initial results for ASDEX and NSTX will be presented using up to 200 modes in both the radial and vertical dimensions.

Anti-alias filter in AORSA for modeling ICRF heating of DT plasmas in ITER

NASA Astrophysics Data System (ADS)

Berry, L. A.; Batchelor, D. B.; Jaeger, E. F.; RF SciDAC Team

2011-10-01

The spectral wave solver AORSA has been used extensively to model full-field, ICRF heating scenarios for DT plasmas in ITER. In these scenarios, the tritium (T) second harmonic cyclotron resonance is positioned near the magnetic axis, where fast magnetosonic waves are efficiently absorbed by tritium ions. In some cases, a fundamental deuterium (D) cyclotron layer can also be located within the plasma, but close to the high field boundary. In this case, the existence of multiple ion cyclotron resonances presents a serious challenge for numerical simulation because short-wavelength, mode-converted waves can be excited close to the plasma edge at the ion-ion hybrid layer. Although the left hand circularly polarized component of the wave field is partially shielded from the fundamental D resonance, some power penetrates, and a small fraction (typically <10%) can be absorbed by the D ions. We find that an anti-aliasing filter is required in AORSA to calculate this fraction correctly while including up-shift and down-shift in the parallel wave spectrum. Work supported by U.S. DOE under Contract DE-AC05-00OR22725 with UT-Battelle, LLC.

The IAU Division A Working Group on the Third Realization of the ICRF: Background, Goals, Plans

NASA Astrophysics Data System (ADS)

Gaume, Ralph

2015-08-01

The XXVIII General Assembly of the IAU (Beijing, 2012) established the Division A Working Group on the Third Realization of the International Celestial Reference Frame (ICRF). The adopted charter of the ICRF3 Working Group includes a commitment to report on the implementation and execution plans for ICRF3 during the XXIX General Assembly of the IAU along with a targeted completion and presentation of ICRF3 in 2018 to the XXX General Assembly for adoption. This talk will discuss the background, purpose, and overall implementation plan for ICRF3, and motivate the concept, currently under consideration by the ICRF3 Working Group, that future realizations of the ICRF be based on multi-frequency astrometric data, starting with ICRF3.

The Position/Structure Stability of Four ICRF2 Sources

NASA Technical Reports Server (NTRS)

Fomalont, Ed; Johnston, Kenneth; Fey, Alan; Boboltz, Dave; Oyama, Tomoaki; Honma, Mareki

2010-01-01

Four compact radio sources in the International Celestial Reference Frame (ICRF2) catalog were observed using phase referencing with the VLBA at 43, 23, and 8.6-GHz, and with VERA at 23-GHz over a one-year period. The goal was to determine the stability of the radio cores and to assess structure effects associated with positions in the ICRF2. Conclusions are: (1) 43-GHz VLBI high-resolution observations are often needed to determine the location of the radio core. (2) Over the observing period, the relative positions among the four radio cores were constant to 0.02 mas, suggesting that once the true radio core is identified, it remains stationary in the sky to this accuracy. (3) The emission in 0556+238, one of the four sources investigated and one of the 295 ICRF2 defining sources, was dominated by a strong component near the core and moved 0.1 mas during the year. (4) Comparison of the VLBA images at 43, 23, and 8.6-GHz with the ICRF2 positions suggests that the 8-GHz structure is often dominated by a bright non-core component. The measured ICRF2 position can be displaced more than 0.5 mas from the radio core and partake in the motion of the bright jet component.

IShTAR ICRF antenna field characterization in vacuum and plasma by using probe diagnostic

NASA Astrophysics Data System (ADS)

Usoltceva, Mariia; Ochoukov, Roman; D'Inca, Rodolphe; Jacquot, Jonathan; Crombé, Kristel; Kostic, Ana; Heuraux, Stéphane; Faudot, Eric; Noterdaeme, Jean-Marie

2017-10-01

RF sheath physics is one of the key topics relevant for improvements of ICRF heating systems, which are present on nearly all modern magnetic fusion machines. This paper introduces developement and validation of a new approach to understanding general RF sheath physics. The presumed reason of enhanced plasma-antenna interactions, parallel electric field, is not measured directly, but proposed to be obtained from simulations in COMSOL Multiphysics® Modeling Software. Measurements of RF magnetic field components with B-dot probes are done on a linear device IShTAR (Ion cyclotron Sheath Test ARrangement) and then compared to simulations. Good resulting accordance is suggested to be the criterion for trustworthiness of parallel electric field estimation as a component of electromagnetic field in modeling. A comparison between simulation and experiment for one magnetic field component in vacuum has demonstrated a close match. An additional complication to this ICRF antenna field characterization study is imposed by the helicon antenna which is used as a plasma ignition tool in the test arrangement. The plasma case, in contrast to the vacuum case, must be approached carefully, since the overlapping of ICRF antenna and helicon antenna fields occurs. Distinguishing of the two fields is done by an analysis of correlation between measurements with both antennas together and with each one separately.

Potential Refinement of the ICRF

NASA Technical Reports Server (NTRS)

Ma, Chopo

2003-01-01

The analysis and data used for the ICRF represented the state of the art in global, extragalactic, X/S band microwave astrometry in 1995. The same general analysis method was used to extend the ICRF with subsequent VLBI data in a manner consistent with the original catalog. Since 1995 there have been considerable advances in the geodetic/astrometric VLBI data set and in the analysis that would significantly improve the systematic errors, stability, and density of the next realization of the ICRS when the decision is made to take this step. In particular, data acquired since 1990, including extensive use of the VLBA, are of higher quality and astrometric utility because of changes in instrumentation, schedule design, and networks as well as specifically astrometric intent. The IVS (International VLBI Service for Geodesy and Astrometry) continues to devote a portion of its observing capability to systematic extension of the astrometric data set. Sufficient data distribution exists to select a better set of defining sources. Improvements in troposphere modeling will minimize known systematic astrometric errors while accurate modeling and estimation of station effects from loading and nonlinear motions will permit the reintegration of the celestial reference frame, terrestrial reference frame and Earth orientation parameters though a single VLBI solution. The differences between the current ICRF and the potential next realization will be described.

IVS Observation of ICRF2-Gaia Transfer Sources

NASA Astrophysics Data System (ADS)

Le Bail, K.; Gipson, J. M.; Gordon, D.; MacMillan, D. S.; Behrend, D.; Thomas, C. C.; Bolotin, S.; Himwich, W. E.; Baver, K. D.; Corey, B. E.; Titus, M.; Bourda, G.; Charlot, P.; Collioud, A.

2016-03-01

The second realization of the International Celestial Reference Frame (ICRF2), which is the current fundamental celestial reference frame adopted by the International Astronomical Union, is based on Very Long Baseline Interferometry (VLBI) data at radio frequencies in X band and S band. The European Space Agency’s Gaia mission, launched on 2013 December 19, started routine scientific operations in 2014 July. By scanning the whole sky, it is expected to observe ∼500,000 Quasi Stellar Objects in the optical domain an average of 70 times each during the five years of the mission. This means that, in the future, two extragalactic celestial reference frames, at two different frequency domains, will coexist. It will thus be important to align them very accurately. In 2012, the Laboratoire d’Astrophysique de Bordeaux (LAB) selected 195 sources from ICRF2 that will be observed by Gaia and should be suitable for aligning the radio and optical frames: they are called ICRF2-Gaia transfer sources. The LAB submitted a proposal to the International VLBI Service (IVS) to regularly observe these ICRF2-Gaia transfer sources at the same rate as Gaia observes them in the optical realm, e.g., roughly once a month. We describe our successful effort to implement such a program and report on the results. Most observations of the ICRF2-Gaia transfer sources now occur automatically as part of the IVS source monitoring program, while a subset of 37 sources requires special attention. Beginning in 2013, we scheduled 25 VLBI sessions devoted in whole or in part to measuring these 37 sources. Of the 195 sources, all but one have been successfully observed in the 12 months prior to 2015 September 01. Of the sources, 87 met their observing target of 12 successful sessions per year. The position uncertainties of all of the ICRF2-Gaia transfer sources have improved since the start of this observing program. For a subset of 24 sources whose positions were very poorly known, the uncertainty

The International Celestial Reference Frame (ICRF) and the Relationship Between Frames

NASA Technical Reports Server (NTRS)

Ma, Chopo

2000-01-01

The International Celestial Reference Frame (ICRF), a catalog of VLBI source positions, is now the basis for astrometry and geodesy. Its construction and extension/maintenance will be discussed as well as the relationship of the ICRF, ITRF, and EOP/nutation.

THE POSITION/STRUCTURE STABILITY OF FOUR ICRF2 SOURCES

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

Fomalont, Ed; Johnston, Kenneth; Fey, Alan

2011-03-15

Four close radio sources in the International Celestial Reference Frame (ICRF) catalog were observed using phase referencing with the VLBA at 43, 23, and 8.6 GHz, and with VERA at 23 GHz over a one-year period. The goal was to determine the stability of the radio cores and to assess structure effects associated with positions in the ICRF. Although the four sources were compact at 8.6 GHz, the VLBA images at 43 GHz with 0.3 mas resolution showed that all were composed of several components. A component in each source was identified as the radio core using some or allmore » of the following emission properties: compactness, spectral index, location at the end of the extended emission region, and stationary in the sky. Over the observing period, the relative positions between the four radio cores were constant to 0.02 mas, the phase-referencing positional accuracy obtained at 23 and 43 GHz among the sources, suggesting that once a radio core is identified, it remains stationary in the sky to this accuracy. Other radio components in two of the four sources had detectable motion in the radio jet direction. Comparison of the 23 and 43 GHz VLBA images with the VLBA 8.6 GHz images and the ICRF positions suggests that some ICRF positions are dominated by a moving jet component; hence, they can be displaced up to 0.5 mas from the radio core and may also reflect the motion of the jet component. Future astrometric efforts to determine a more accurate quasar reference frame at 23 and 43 GHz and from the VLBI2010 project are discussed, and supporting VLBA or European VLBI Network observations of ICRF sources at 43 GHz are recommended in order to determine the internal structure of the sources. A future collaboration between the radio (ICRF) and the optical frame of GAIA is discussed.« less

Acceleration of Dense Flowing Plasmas using ICRF Power in the VASIMR Experiment

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

Squire, Jared P.

2005-09-26

ICRF power in the Variable Specific Impulse Magnetoplasma Rocket (VASIMR) concept energizes ions (> 100 eV) in a diverging magnetic field to accelerate a dense ({approx} 1019 m-3) flowing plasma to velocities useful for space propulsion ({approx}100 km/s). Theory predicts that an ICRF slow wave launched from the high field side of the resonance will propagate in the magnetic beach to absorb nearly all of the power at the resonance, thus efficiently converting the RF power to ion kinetic energy. The plasma flows through the resonance only once, so the ions are accelerated in a single pass. This process hasmore » proven efficient ({approx} 70%) with an ICRF power level of 1.5 kW at about 3.6 MHz in the VASIMR experiment, VX-30, using deuterium plasma created by a helicon operating in flowing mode. We have measured ICRF plasma loading up to 2 ohms, consistent with computational predictions made using Oak Ridge National Laboratory's EMIR code. Recent helicon power upgrades (20 kW at 13.56 MHz) have enabled a 5 cm diameter target plasma for ICRF with an ion flux of over 3x10 20 s-1 and a high degree of ionization. This paper summarizes our ICRF results and presents the latest helicon developments in VX-30.« less

Modeling of the EAST ICRF antenna with ICANT Code

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

Qin Chengming; Zhao Yanping; Colas, L.

2007-09-28

A Resonant Double Loop (RDL) antenna for ion-cyclotron range of frequencies (ICRF) on Experimental Advanced Superconducting Tokamak (EAST) is under construction. The new antenna is analyzed using the antenna coupling code ICANT which self-consistently determines the surface currents on all antenna parts. In this work, the modeling of the new ICRF antenna using this code is to assess the near-fields in front of the antenna and analysis its coupling capabilities. Moreover, the antenna reactive radiated power computed by ICANT and shows a good agreement with deduced from Transmission Line (TL) theory.

Modeling of the EAST ICRF antenna with ICANT Code

NASA Astrophysics Data System (ADS)

Qin, Chengming; Zhao, Yanping; Colas, L.; Heuraux, S.

2007-09-01

A Resonant Double Loop (RDL) antenna for ion-cyclotron range of frequencies (ICRF) on Experimental Advanced Superconducting Tokamak (EAST) is under construction. The new antenna is analyzed using the antenna coupling code ICANT which self-consistently determines the surface currents on all antenna parts. In this work, the modeling of the new ICRF antenna using this code is to assess the near-fields in front of the antenna and analysis its coupling capabilities. Moreover, the antenna reactive radiated power computed by ICANT and shows a good agreement with deduced from Transmission Line (TL) theory.

Minority heating scenarios in ^4He(H) and ^3He(H) SST-1 plasmas

NASA Astrophysics Data System (ADS)

Chattopadhyay, Asim Kumar

2018-01-01

A numerical analysis of ion cyclotron resonance heating scenarios in two species of low ion temperature plasma has been done to elucidate the physics and possibility to achieve H-mode in tokamak plasma. The analysis is done in the steady-state superconducting tokamak, SST-1, using phase-I plasma parameters which is basically L-mode plasma parameters having low ion temperature and magnetic field with the help of the ion cyclotron heating code TORIC combined with `steady state Fokker-Planck quasilinear' (SSFPQL) solver. As a minority species hydrogen has been used in ^3He and ^4He plasmas to make two species ^3He(H) and ^4He(H) plasmas to study the ion cyclotron wave absorption scenarios. The minority heating is predominant in ^3He(H) and ^4He(H) plasmas as minority resonance layers are not shielded by ion-ion resonance and cut-off layers in both cases, and it is better in ^4He(H) plasma due to the smooth penetration of wave through plasma-vacuum surface. In minority concentration up to 15%, it has been observed that minority ion heating is the principal heating mechanism compared to electron heating and heating due to mode conversion phenomena. Numerical analysis with the help of SSFPQL solver shows that the tail of the distribution function of the minority ion is more energetic than that of the majority ion and therefore, more anisotropic. Due to good coupling of the wave and predominance of the minority heating regime, producing energetic ions in the tail region of the distribution function, the ^4He(H) and ^3He(H) plasmas could be studied in-depth to achieve H-mode in two species of low-temperature plasma.

Progress on ion cyclotron range of frequencies heating physics and technology in support of the International Tokamak Experimental Reactor

NASA Astrophysics Data System (ADS)

Wilson, J. R.; Bonoli, P. T.

2015-02-01

Ion cyclotron range of frequency (ICRF) heating is foreseen as an integral component of the initial ITER operation. The status of ICRF preparations for ITER and supporting research were updated in the 2007 [Gormezano et al., Nucl. Fusion 47, S285 (2007)] report on the ITER physics basis. In this report, we summarize progress made toward the successful application of ICRF power on ITER since that time. Significant advances have been made in support of the technical design by development of new techniques for arc protection, new algorithms for tuning and matching, carrying out experimental tests of more ITER like antennas and demonstration on mockups that the design assumptions are correct. In addition, new applications of the ICRF system, beyond just bulk heating, have been proposed and explored.

Sequential modelling of ICRF wave near RF fields and asymptotic RF sheaths description for AUG ICRF antennas

NASA Astrophysics Data System (ADS)

Jacquot, Jonathan; Tierens, Wouter; Zhang, Wei; Bobkov, Volodymyr; Colas, Laurent; Noterdaeme, Jean-Marie

2017-10-01

A sequence of simulations is performed with RAPLICASOL and SSWICH to compare two AUG ICRF antennas. RAPLICASOL outputs have been used as input to SSWICH-SW for the AUG ICRF antennas. Using parallel electric field maps and the scattering matrix produced by RAPLICASOL, SSWICH-SW, reduced to its asymptotic part, is able to produce a 2D radial/poloidal map of the DC plasma potential accounting for the antenna input settings (total power, power balance, phasing). Two models of antennas are compared: 2-strap antenna vs 3-strap antenna. The 2D DC potential structures are correlated to structures of the parallel electric field map for different phasing and power balance. The overall DC plasma potential on the 3-strap antenna is lower due to better global RF currents compensation. Spatial proximity between regions of high RF electric field and regions where high DC plasma potentials are observed is an important factor for sheath rectification.

ICRF mode conversion in three-ion species heating experiment and in flow drive experiment on the Alcator C-Mod tokamak

NASA Astrophysics Data System (ADS)

Lin, Y.; Wukitch, S. J.; Edlund, E.; Ennever, P.; Hubbard, A. E.; Porkolab, M.; Rice, J.; Wright, J.

2017-10-01

In recent three-ion species (majority D and H plus a trace level of 3He) ICRF heating experiments on Alcator C-Mod, double mode conversion on both sides of the 3He cyclotron resonance has been observed using the phase contrast imaging (PCI) system. The MC locations are used to estimate the species concentrations in the plasma. Simulation using TORIC shows that with the 3He level <1%, most RF power is absorbed by the 3He ions and the process can generate energetic 3He ions. In mode conversion (MC) flow drive experiment in D(3He) plasma at 8 T, MC waves were also monitored by PCI. The MC ion cyclotron wave (ICW) amplitude and wavenumber kR have been found to correlate with the flow drive force. The MC efficiency, wave-number k of the MC ICW and their dependence on plasma parameters like Te0 have been studied. Based on the experimental observation and numerical study of the dispersion solutions, a hypothesis of the flow drive mechanism has been proposed.

Density Convection near Radiating ICRF Antennas and its Effect on the Coupling of Lower Hybrid Waves

NASA Astrophysics Data System (ADS)

Ekedahl, A.; Colas, L.; Mayoral, M.-L.; Beaumont, B.; Bibet, Ph.; Brémond, S.; Kazarian, F.; Mailloux, J.; Noterdaeme, J.-M.; Efda-Jet Contributors

2003-12-01

Combined operation of Lower Hybrid (LH) and Ion Cyclotron Resonance Frequency (ICRF) waves can result in a degradation of the LH wave coupling, as observed both in the Tore Supra and JET tokamaks. The reflection coefficient on the part of the LH launcher magnetically connected to the powered ICRF antenna increases, suggesting a local decrease in the electron density in the connecting flux tubes. This has been confirmed by Langmuir probe measurements on the LH launchers in the latest Tore Supra experiments. Moreover, recent experiments in JET indicate that the LH coupling degradation depends on the ICRF power and its launched k//-spectrum. The 2D density distribution around the Tore Supra ICRF antennas has been modelled with the CELLS-code, balancing parallel losses with diffusive transport and sheath induced E×B convection, obtained from RF field mapping using the ICANT-code. The calculations are in qualitative agreement with the experimental observations, i.e. density depletion is obtained, localised mainly in the antenna shadow, and dependent on ICRF power and antenna spectrum.

High-Performance Computational Modeling of ICRF Physics and Plasma-Surface Interactions in Alcator C-Mod

NASA Astrophysics Data System (ADS)

Jenkins, Thomas; Smithe, David

2016-10-01

Inefficiencies and detrimental physical effects may arise in conjunction with ICRF heating of tokamak plasmas. Large wall potential drops, associated with sheath formation near plasma-facing antenna hardware, give rise to high-Z impurity sputtering from plasma-facing components and subsequent radiative cooling. Linear and nonlinear wave excitations in the plasma edge/SOL also dissipate injected RF power and reduce overall antenna efficiency. Recent advances in finite-difference time-domain (FDTD) modeling techniques allow the physics of localized sheath potentials, and associated sputtering events, to be modeled concurrently with the physics of antenna near- and far-field behavior and RF power flow. The new methods enable time-domain modeling of plasma-surface interactions and ICRF physics in realistic experimental configurations at unprecedented spatial resolution. We present results/animations from high-performance (10k-100k core) FDTD/PIC simulations spanning half of Alcator C-Mod at mm-scale resolution, exploring impurity production due to localized sputtering (in response to self-consistent sheath potentials at antenna surfaces) and the physics of parasitic slow wave excitation near the antenna hardware and SOL. Supported by US DoE (Award DE-SC0009501) and the ALCC program.

ICRF operation with improved antennas in ASDEX Upgrade with W wall

NASA Astrophysics Data System (ADS)

Bobkov, V.; Balden, M.; Bilato, R.; Braun, F.; Dux, R.; Herrmann, A.; Faugel, H.; Fünfgelder, H.; Giannone, L.; Kallenbach, A.; Maier, H.; Müller, H. W.; Neu, R.; Noterdaeme, J.-M.; Pütterich, Th.; Rohde, V.; Tsujii, N.; Zeus, F.; Zohm, H.; the ASDEX Upgrade Team

2013-09-01

Experiments with boron-coated side limiters of two antennas operated together in 2012 showed that the side limiters are responsible for more than half of the increased W content in the plasma. Together with the contribution from the other limiter tiles, not replaced in 2012, the limiters account for at least two thirds of the W content. A modified test two-strap ion cyclotron range of frequency (ICRF) antennas in ASDEX Upgrade with broad limiters and narrow straps has shown an improved operation with full W wall in 2011/2012 campaigns with up to a 40% lower rise of W concentration allowing more stable operation at low deuterium gas injection rate. Limiter spectroscopy measurements indicate up to a 40% reduction of the rise of the W sputtering yield during ICRF power, measured under the assumption of negligible influence of geometry variations and reflections on the measurements. The boron limiters on two antennas together with the improved broad-limiter antenna allowed a successful ICRF operation in 2012. As a part of long-term strategy of antenna design development, two three-strap antennas with phase and power balance control for reduction of E‖ are planned for installation in the future.

VizieR Online Data Catalog: Radio fluxes of 195 ICRF2-Gaia transfer sources (Le Bail+, 2016)

NASA Astrophysics Data System (ADS)

Le Bail, K.; Gipson, J. M.; Gordon, D.; MacMillan, D. S.; Behrend, D.; Thomas, C. C.; Bolotin, S.; Himwich, W. E.; Baver, K. D.; Corey, B. E.; Titus, M.; Bourda, G.; Charlot, P.; Collioud, A.

2016-07-01

The second realization of the International Celestial Reference Frame (ICRF2) is based on Very Long Baseline Interferometry (VLBI) data at radio frequencies in X band and S band. The European Space Agency's Gaia mission, launched on 2013 December 19, started routine scientific operations in 2014 July. By scanning the whole sky, it is expected to observe ~500000 Quasi Stellar Objects in the optical domain. This means that, in the future, two extragalactic celestial reference frames, at two different frequency domains, will coexist. It will thus be important to align them very accurately. In 2012, the Laboratoire d'Astrophysique de Bordeaux (LAB) selected 195 sources from ICRF2 that will be observed by Gaia and should be suitable for aligning the radio and optical frames: they are called ICRF2-Gaia transfer sources. The LAB submitted a proposal to the International VLBI Service (IVS) to regularly observe these ICRF2-Gaia transfer sources at the same rate as Gaia observes them in the optical realm, e.g., roughly once a month. Of the 195 sources, all but one have been successfully observed in the 12 months prior to 2015 September 01. Table1 lists the 195 ICRF2-Gaia transfer sources. Beginning in 2003 June, the Goddard VLBI group developed a program to purposefully monitor when sources were observed and to increase the observations of "under-observed" sources. In 2013 March, we added all 195 ICRF2-Gaia transfer sources to the IVS source monitoring program with an observation target of 12 successful sessions per year. (1 data file).

Operation of ICRF antennas in a full tungsten environment in ASDEX Upgrade

NASA Astrophysics Data System (ADS)

Bobkov, Vl.; Braun, F.; Dux, R.; Giannone, L.; Herrmann, A.; Kallenbach, A.; Müller, H. W.; Neu, R.; Noterdaeme, J.-M.; Pütterich, Th.; Rohde, V.; ASDEX Upgrade Team

2009-06-01

In the 2007 and early part of 2008 experimental campaigns, ASDEX Upgrade operated with full tungsten (W) wall without boronization. Use of ICRF power results in a significant increase of W source. Low temperature conditions at the plasma facing components, achieved by a large clearance between the separatrix and the antenna (>6 cm) and by elevated gas puff rates (>5×1021 s) help to lower W sputtering yield during ICRF. Operation of neighboring ICRF antennas at the phase difference close to -90° can lead to a reduction in the W source. However, a reduction of parallel near-fields by antenna design is needed to further minimize the W source. A relation has been established between the HFSS code calculations predicting a dominant role of box currents in the formation of parallel antenna near-fields and the experiment. The shapes of the measured vertical profile of effective sputtering yields and the calculated sheath driving voltages show a qualitative agreement. This confirms that the existing tools are a good basis to design an improved antenna.

Long-Term Variations of the EOP and ICRF2

NASA Technical Reports Server (NTRS)

Zharov, Vladimir; Sazhin, Mikhail; Sementsov, Valerian; Sazhina, Olga

2010-01-01

We analyzed the time series of the coordinates of the ICRF radio sources. We show that part of the radio sources, including the defining sources, shows a significant apparent motion. The stability of the celestial reference frame is provided by a no-net-rotation condition applied to the defining sources. In our case this condition leads to a rotation of the frame axes with time. We calculated the effect of this rotation on the Earth orientation parameters (EOP). In order to improve the stability of the celestial reference frame we suggest a new method for the selection of the defining sources. The method consists of two criteria: the first one we call cosmological and the second one kinematical. It is shown that a subset of the ICRF sources selected according to cosmological criteria provides the most stable reference frame for the next decade.

Effect on the tritium breeding ratio for a distributed ICRF antenna in a DEMO reactor

NASA Astrophysics Data System (ADS)

Garcia, A.; Noterdaeme, J.-M.; Fischer, U.; Dies, J.

2015-12-01

The paper reports results of MCNP-5 calculations to assess the effect on the Tritium Breeding Ratio (TBR) when integrating a distributed Ion Cyclotron Range of Frequencies (ICRF) antenna in the blanket of DEMO fusion power reactor. The calculations consider different parameters such as the ICRF covering ratio and the type of breeding blanket including the Helium Cooled Pebble Bed (HCPB) and the Helium Cooled Lithium Lead (HCLL) concepts. For an antenna with a full toroidal circumference of 360°, located poloidally at 40° with a poloidal extension of 1 m, the reduction of the TBR is -0.349% for the HCPB blanket and -0.532% for the HCLL blanket. The distributed ICRF antenna is thus shown to have only a marginal effect on the TBR of the DEMO reactor.

Arc detection for the ICRF system on ITER

NASA Astrophysics Data System (ADS)

D'Inca, R.

2011-12-01

The ICRF system for ITER is designed to respect the high voltage breakdown limits. However arcs can still statistically happen and must be quickly detected and suppressed by shutting the RF power down. For the conception of a reliable and efficient detector, the analysis of the mechanism of arcs is necessary to find their unique signature. Numerous systems have been conceived to address the issues of arc detection. VSWR-based detectors, RF noise detectors, sound detectors, optical detectors, S-matrix based detectors. Until now, none of them has succeeded in demonstrating the fulfillment of all requirements and the studies for ITER now follow three directions: improvement of the existing concepts to fix their flaws, development of new theoretically fully compliant detectors (like the GUIDAR) and combination of several detectors to benefit from the advantages of each of them. Together with the physical and engineering challenges, the development of an arc detection system for ITER raises methodological concerns to extrapolate the results from basic experiments and present machines to the ITER scale ICRF system and to conduct a relevant risk analysis.

Effect on the tritium breeding ratio for a distributed ICRF antenna in a DEMO reactor

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

Garcia, A., E-mail: albert.garcia.hp@gmail.com; Karlsruhe Institute of Technology; Polytechnic University of Catalonia

The paper reports results of MCNP-5 calculations to assess the effect on the Tritium Breeding Ratio (TBR) when integrating a distributed Ion Cyclotron Range of Frequencies (ICRF) antenna in the blanket of DEMO fusion power reactor. The calculations consider different parameters such as the ICRF covering ratio and the type of breeding blanket including the Helium Cooled Pebble Bed (HCPB) and the Helium Cooled Lithium Lead (HCLL) concepts. For an antenna with a full toroidal circumference of 360°, located poloidally at 40° with a poloidal extension of 1 m, the reduction of the TBR is −0.349% for the HCPB blanket andmore » −0.532% for the HCLL blanket. The distributed ICRF antenna is thus shown to have only a marginal effect on the TBR of the DEMO reactor.« less

Northern Hemisphere observations of ICRF sources on the USNO stellar catalogue frame

NASA Astrophysics Data System (ADS)

Fienga, A.; Andrei, A. H.

2004-06-01

The most recent USNO stellar catalogue, the USNO B1.0 (Monet et al. \\cite{Monet03}), provides positions for 1 042 618 261 objects, with a published astrometric accuracy of 200 mas and five-band magnitudes with a 0.3 mag accuracy. Its completeness is believed to be up to magnitude 21th in V-band. Such a catalogue would be a very good tool for astrometric reduction. This work investigates the accuracy of the USNO B1.0 link to ICRF and give an estimation of its internal and external accuracies by comparison with different catalogues, and by computation of ICRF sources using USNO B1.0 star positions.

Implementation of the new multichannel X-mode edge density profile reflectometer for the ICRF antenna on ASDEX Upgrade

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

Aguiam, D. E., E-mail: daguiam@ipfn.tecnico.ulisboa.pt; Silva, A.; Carvalho, P. J.

A new multichannel frequency modulated continuous-wave reflectometry diagnostic has been successfully installed and commissioned on ASDEX Upgrade to measure the plasma edge electron density profile evolution in front of the Ion Cyclotron Range of Frequencies (ICRF) antenna. The design of the new three-strap ICRF antenna integrates ten pairs (sending and receiving) of microwave reflectometry antennas. The multichannel reflectometer can use three of these to measure the edge electron density profiles up to 2 × 10{sup 19} m{sup −3}, at different poloidal locations, allowing the direct study of the local plasma layers in front of the ICRF antenna. ICRF power coupling,more » operational effects, and poloidal variations of the plasma density profile can be consistently studied for the first time. In this work the diagnostic hardware architecture is described and the obtained density profile measurements were used to track outer radial plasma position and plasma shape.« less

The ITER ICRF Antenna Design with TOPICA

NASA Astrophysics Data System (ADS)

Milanesio, Daniele; Maggiora, Riccardo; Meneghini, Orso; Vecchi, Giuseppe

2007-11-01

TOPICA (Torino Polytechnic Ion Cyclotron Antenna) code is an innovative tool for the 3D/1D simulation of Ion Cyclotron Radio Frequency (ICRF), i.e. accounting for antennas in a realistic 3D geometry and with an accurate 1D plasma model [1]. The TOPICA code has been deeply parallelized and has been already proved to be a reliable tool for antennas design and performance prediction. A detailed analysis of the 24 straps ITER ICRF antenna geometry has been carried out, underlining the strong dependence and asymmetries of the antenna input parameters due to the ITER plasma response. We optimized the antenna array geometry dimensions to maximize loading, lower mutual couplings and mitigate sheath effects. The calculated antenna input impedance matrices are TOPICA results of a paramount importance for the tuning and matching system design. Electric field distributions have been also calculated and they are used as the main input for the power flux estimation tool. The designed optimized antenna is capable of coupling 20 MW of power to plasma in the 40 -- 55 MHz frequency range with a maximum voltage of 45 kV in the feeding coaxial cables. [1] V. Lancellotti et al., Nuclear Fusion, 46 (2006) S476-S499

Linking Deep Astrometric Standards to the ICRF

NASA Astrophysics Data System (ADS)

Frey, S.; Platais, I.; Fey, A. L.

2007-07-01

The next-generation large aperature and large field-of-view telescopes will address fundamantal questions of astrophysica and cosmology such as the nature of dark matter and dark energy. For a variety of applications, the CCD mosaic detectors in the focal plane arrays require astronomic calibrationat the milli-arcsecond (mas) level. The existing optical reference frames are insufficient to support such calibrations. To address this problem, deep optical astronomic fields are being established near the Galactic plane. In order to achiev a 5-10-mas or better positional accuracyfor the Deepp Astrometric Standards (DAS), and to obtain bsolute stellar proper motions for the study of Galactic structure, it is crucial to link these fields to the International Celestial Reference Frame (ICRF). To this end, we selected 15 candidate compact extragalactic radio sources in the Gemini-Orion-Taurus (GOT) field. These sources were observed with the European VLBI Network (EVN) at 5 GHz in phase-reference mode. The bright compact calibrator source J0603+2159 and seven other sources were detected and imaged at the angular resolution of -1.5-8 mas. Relative astrometric positions were derived for these sources at a milli-arcsecond accuracy level. The detection of the optical counterparts of these extragalactic radio sources will allow us to establish a direct link to the ICRF locally in the GOT field.

Extreme heat and cultural and linguistic minorities in Australia: perceptions of stakeholders.

PubMed

Hansen, Alana; Nitschke, Monika; Saniotis, Arthur; Benson, Jill; Tan, Yan; Smyth, Val; Wilson, Leigh; Han, Gil-Soo; Mwanri, Lillian; Bi, Peng

2014-06-03

Despite acclimatisation to hot weather, many individuals in Australia are adversely affected by extreme heat each summer, placing added pressure on the health sector. In terms of public health, it is therefore important to identify vulnerable groups, particularly in the face of a warming climate. International evidence points to a disparity in heat-susceptibility in certain minority groups, although it is unknown if this occurs in Australia. With cultural diversity increasing, the aim of this study was to explore how migrants from different cultural backgrounds and climate experiences manage periods of extreme heat in Australia. A qualitative study was undertaken across three Australian cities, involving interviews and focus groups with key informants including stakeholders involved in multicultural service provision and community members. Thematic analysis and a framework approach were used to analyse the data. Whilst migrants and refugees generally adapt well upon resettlement, there are sociocultural barriers encountered by some that hinder environmental adaptation to periods of extreme heat in Australia. These barriers include socioeconomic disadvantage and poor housing, language barriers to the access of information, isolation, health issues, cultural factors and lack of acclimatisation. Most often mentioned as being at risk were new arrivals, people in new and emerging communities, and older migrants. With increasing diversity within populations, it is important that the health sector is aware that during periods of extreme heat there may be disparities in the adaptive capacity of minority groups, underpinned by sociocultural and language-based vulnerabilities in migrants and refugees. These factors need to be considered by policymakers when formulating and disseminating heat health strategies.

Mode conversion in ICRF experiments on Alcator C-Mod

NASA Astrophysics Data System (ADS)

Lin, Y.; Wukitch, S. J.; Edlund, E.; Ennever, P.; Hubbard, A. E.; Porkolab, M.; Rice, J.; Wright, J.

2017-10-01

In recent three-ion species (majority D and H plus a trace level of 3He) ICRF heating experiment on Alcator C-Mod, double mode conversion on both sides of the 3He cyclotron resonance has been observed using the phase contrast imaging (PCI) system. The MC locations are used to estimate the species concentrations in the plasma. Simulation using TORIC shows that with the 3He level <1%, most RF power is absorbed by the 3He ions and the process can generate energetic 3He ions. In recent mode conversion flow drive experiment in D(3He) plasma at 8 T, MC waves were also monitored by PCI. The MC ion cyclotron wave (ICW) amplitude and wavenumber kR have been found to correlate with the flow drive force. The MC efficiency, wave-number k of the MC ICW and their dependence on plasma parameters like Te0 are shown to play important roles. Based on the experimental observation and numerical study of the dispersion solutions, a hypothesis of the flow drive mechanism has been proposed. Supported by USDoE awards DE-FC02-99ER54512.

Optical Spectra of Candidate International Celestial Reference Frame (ICRF) Flat-spectrum Radio Sources. III.

NASA Astrophysics Data System (ADS)

Titov, O.; Pursimo, T.; Johnston, Helen M.; Stanford, Laura M.; Hunstead, Richard W.; Jauncey, David L.; Zenere, Katrina A.

2017-04-01

In extending our spectroscopic program, which targets sources drawn from the International Celestial Reference Frame (ICRF) Catalog, we have obtained spectra for ˜160 compact, flat-spectrum radio sources and determined redshifts for 112 quasars and radio galaxies. A further 14 sources with featureless spectra have been classified as BL Lac objects. Spectra were obtained at three telescopes: the 3.58 m European Southern Observatory New Technology Telescope, and the two 8.2 m Gemini telescopes in Hawaii and Chile. While most of the sources are powerful quasars, a significant fraction of radio galaxies is also included from the list of non-defining ICRF radio sources.

Optical Spectra of Candidate International Celestial Reference Frame (ICRF) Flat-spectrum Radio Sources. III

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

Titov, O.; Stanford, Laura M.; Pursimo, T.

In extending our spectroscopic program, which targets sources drawn from the International Celestial Reference Frame (ICRF) Catalog, we have obtained spectra for ∼160 compact, flat-spectrum radio sources and determined redshifts for 112 quasars and radio galaxies. A further 14 sources with featureless spectra have been classified as BL Lac objects. Spectra were obtained at three telescopes: the 3.58 m European Southern Observatory New Technology Telescope, and the two 8.2 m Gemini telescopes in Hawaii and Chile. While most of the sources are powerful quasars, a significant fraction of radio galaxies is also included from the list of non-defining ICRF radiomore » sources.« less

Transport and Stability in C-Mod ITBs in Diverse Regimes

NASA Astrophysics Data System (ADS)

Fiore, C. L.; Ernst, D. R.; Howard, N. T.; Kasten, C. P.; Mikkelsen, D.; Reinke, M. L.; Rice, J. E.; White, A. E.; Rowan, W. L.; Bespamyatnov, I.

2012-10-01

Internal Transport Barriers (ITBs) in C-Mod feature highly peaked density and pressure profiles and are typically induced by the introduction of radio frequency power in the ion cyclotron range of frequencies (ICRF) with the second harmonic of the resonance for minority hydrogen ions positioned off-axis at the plasma half radius on either the low or high field side of the plasma. These ITBs are formed in the absence of particle or momentum injection, and with monotonic q profiles with qmin< 1. Thus they allow exploration of ITB dynamics in a reactor relevant regime. Recently, linear and non-linear gyrokinetic simulations have demonstrated that changes in the ion temperature and plasma rotation profiles, coincident with the application of off-axis ICRF heating, contribute to greater stability to ion temperature gradient driven fluctuation in the plasma. This results in reduced turbulent driven outgoing heat flux. To date, ITB formation in C-Mod has only been observed in EDA H-mode plasmas with moderate (2-3 MW) ICRF power. Experiments to explore the formation of ITBs in other operating regimes such as I-mode and also with high ICRF power are being undertaken to understand further the process of ITB formation and sustainment, especially with regard to turbulent driven transport.

Extreme heat and cultural and linguistic minorities in Australia: perceptions of stakeholders

PubMed Central

2014-01-01

Background Despite acclimatisation to hot weather, many individuals in Australia are adversely affected by extreme heat each summer, placing added pressure on the health sector. In terms of public health, it is therefore important to identify vulnerable groups, particularly in the face of a warming climate. International evidence points to a disparity in heat-susceptibility in certain minority groups, although it is unknown if this occurs in Australia. With cultural diversity increasing, the aim of this study was to explore how migrants from different cultural backgrounds and climate experiences manage periods of extreme heat in Australia. Methods A qualitative study was undertaken across three Australian cities, involving interviews and focus groups with key informants including stakeholders involved in multicultural service provision and community members. Thematic analysis and a framework approach were used to analyse the data. Results Whilst migrants and refugees generally adapt well upon resettlement, there are sociocultural barriers encountered by some that hinder environmental adaptation to periods of extreme heat in Australia. These barriers include socioeconomic disadvantage and poor housing, language barriers to the access of information, isolation, health issues, cultural factors and lack of acclimatisation. Most often mentioned as being at risk were new arrivals, people in new and emerging communities, and older migrants. Conclusions With increasing diversity within populations, it is important that the health sector is aware that during periods of extreme heat there may be disparities in the adaptive capacity of minority groups, underpinned by sociocultural and language-based vulnerabilities in migrants and refugees. These factors need to be considered by policymakers when formulating and disseminating heat health strategies. PMID:24889099

ICRF wall conditioning at TEXTOR-94 in the presence of a 2.25 T magnetic field

NASA Astrophysics Data System (ADS)

Esser, H. G.; Lyssoivan, A.; Freisinger, M.; Koch, R.; van Oost, G.; Weschenfelder, F.; Winter, J.; Textor-Icrh-Team

1997-02-01

To investigate alternative conditioning concepts for future fusion devices with permanent magnetic fields, plasmas produced by the coupling of ICRF power to He and gas mixtures of Helium + silane, have been analyzed in the presence of a 2.25 T toroidal magnetic field at TEXTOR-94. Their qualification for wall conditioning has been investigated for different He-pressures, PHe (1 × 10 -3 < PHe ( Pa) < 1 × 10 -1) and ICRF power, PICRF (100 < PICRF ( kW) < 800). Electron densities n e averaged along different radial lines of sight across the vacuum vessel from the top to the bottom have been obtained in the range 5 × 10 10 < ne ( cm-3) < 3 × 10 12. To study quantitatively the efficiency of hydrogen desorption from the first wall at different ICRF plasma conditions in a reproducible way, the first wall was presaturated by RG-glow discharges in H 2. The amount and the evolution of the H 2 desorption from rf discharge to rf discharge was determined by ion gauge measurements combined with mass spectrometry. To demonstrate the capability of the new method for plasma assisted thin film deposition, different amounts of silane (<50%) were added to the He gas. During the ICRF pulses, the silane molecules were dissociated in the plasma and the Si atoms stick to the wall. A good balance of the amount of Si disappearing from the gas phase and that measured by post mortem surface analyses of collector probes at the wall position was found.

Electron critical gradient scale length measurements of ICRF heated L-mode plasmas at Alcator C-Mod tokamak

NASA Astrophysics Data System (ADS)

Houshmandyar, S.; Hatch, D. R.; Horton, C. W.; Liao, K. T.; Phillips, P. E.; Rowan, W. L.; Zhao, B.; Cao, N. M.; Ernst, D. R.; Greenwald, M.; Howard, N. T.; Hubbard, A. E.; Hughes, J. W.; Rice, J. E.

2018-04-01

A profile for the critical gradient scale length (Lc) has been measured in L-mode discharges at the Alcator C-Mod tokamak, where electrons were heated by an ion cyclotron range of frequency through minority heating with the intention of simultaneously varying the heat flux and changing the local gradient. The electron temperature gradient scale length (LTe-1 = |∇Te|/Te) profile was measured via the BT-jog technique [Houshmandyar et al., Rev. Sci. Instrum. 87, 11E101 (2016)] and it was compared with electron heat flux from power balance (TRANSP) analysis. The Te profiles were found to be very stiff and already above the critical values, however, the stiffness was found to be reduced near the q = 3/2 surface. The measured Lc profile is in agreement with electron temperature gradient (ETG) models which predict the dependence of Lc-1 on local Zeff, Te/Ti, and the ratio of the magnetic shear to the safety factor. The results from linear Gene gyrokinetic simulations suggest ETG to be the dominant mode of turbulence in the electron scale (k⊥ρs > 1), and ion temperature gradient/trapped electron mode modes in the ion scale (k⊥ρs < 1). The measured Lc profile is in agreement with the profile of ETG critical gradients deduced from Gene simulations.

Characterization and Mitigation of ICRF Antenna - Plasma Edge Interaction

NASA Astrophysics Data System (ADS)

Hong, Rongjie; Tynan, George; Wukitch, Steve; Lin, Yijun; Terry, Jim; Chilenski, M.; Golfinopoulos, T.; Hubbard, A.; Mumgaard, R. T.; Perkins, R.; Reinke, M. L.; Alcator C-Mod Team

2017-10-01

Recent experiments reveal that RF-induced potentials (VRF) in the SOL and impurity source at the antenna can be reduced to background levels via optimizing the power ratio between the inner and outer current straps, Pcent /Pout . Experiments indicate the antenna impurity source reduction for the field aligned antenna is due to geometrical alignment rather than electrical symmetry. Additional experiments performed without an optimized Pcent /Pout showed that VRF and the associated convection cells do not influence the impurity penetration or core impurity confinement. These results suggest the core impurity contamination associated with ICRF heating is dominated by an increased impurity source rather than a change in impurity transport. Further, the convective cell strength was expected to scale inversely with B-field. The observed poloidal velocity (measure of convective cell strength), however, decreased less than expected. In addition, the measured maximum VRF increased and penetrated farther into the SOL at higher B-field and plasma current. Results also suggest VRF is strongly influenced by the SOL plasma parameters rather than by RF parameters. Work supported by the U.S. DoE, Office of Science, Office of Fusion Energy Sciences, User Facility Alcator C-Mod under DE-FC02-99ER54512 and DE-SC 0010720.

Assessment of compatibility of ICRF antenna operation with full W wall in ASDEX Upgrade

NASA Astrophysics Data System (ADS)

Bobkov, Vl. V.; Braun, F.; Dux, R.; Herrmann, A.; Giannone, L.; Kallenbach, A.; Krivska, A.; Müller, H. W.; Neu, R.; Noterdaeme, J.-M.; Pütterich, T.; Rohde, V.; Schweinzer, J.; Sips, A.; Zammuto, I.; ASDEX Upgrade Team

2010-03-01

The compatibility of ICRF (ion cyclotron range of frequencies) antenna operation with high-Z plasma facing components is assessed in ASDEX Upgrade (AUG) with its tungsten (W) first wall. The mechanism of ICRF-related W sputtering was studied by various diagnostics including the local spectroscopic measurements of W sputtering yield YW on antenna limiters. Modification of one antenna with triangular shields, which cover the locations where long magnetic field lines pass only one out of two (0π)-phased antenna straps, did not influence the locally measured YW values markedly. In the experiments with antennas powered individually, poloidal profiles of YW on limiters of powered antennas show high YW close to the equatorial plane and at the very edge of the antenna top. The YW-profile on an unpowered antenna limiter peaks at the location projecting to the top of the powered antenna. An interpretation of the YW measurements is presented, assuming a direct link between the W sputtering and the sheath driving RF voltages deduced from parallel electric near-field (E||) calculations and this suggests a strong E|| at the antenna limiters. However, uncertainties are too large to describe the YW poloidal profiles. In order to reduce ICRF-related rise in W concentration CW, an operational approach and an approach based on calculations of parallel electric fields with new antenna designs are considered. In the operation, a noticeable reduction in YW and CW in the plasma during ICRF operation with W wall can be achieved by (a) increasing plasma-antenna clearance; (b) strong gas puffing; (c) decreasing the intrinsic light impurity content (mainly oxygen and carbon in AUG). In calculations, which take into account a realistic antenna geometry, the high E|| fields at the antenna limiters are reduced in several ways: (a) by extending the antenna box and the surrounding structures parallel to the magnetic field; (b) by increasing the average strap-box distance, e.g. by increasing the

LETTER: Study of combined NBI and ICRF enhancement of the D-3He fusion yield with a Fokker-Planck code

NASA Astrophysics Data System (ADS)

Azoulay, M.; George, M. A.; Burger, A.; Collins, W. E.; Silberman, E.

A two-dimensional bounce averaged Fokker-Planck code is used to study the fusion yield and the wave absorption by residual hydrogen ions in higher harmonic ICRF heating of D (120 keV) and 3He (80 keV) beams in the JT-60U tokamak. Both for the fourth harmonic resonance of 3He (ω = 4ωc3He(0), which is accompanied by the third harmonic resonance of hydrogen (ω = 3ωcH) at the low field side, and for the third harmonic resonance of 3He (ω = 4ωcD(0) = 3ωc3He(0)) = 2ωcH(0)), a few per cent of hydrogen ions are found to absorb a large fraction of the ICRF power and to degrade the fusion output power. In the latter case, D beam acceleration due to the fourth harmonic resonance in the 3He(D) regime can enhance the fusion yield more effectively. A discussion is given of the effect of D beam acceleration due to the fifth harmonic resonance (ω = 5ωcD) at the high field side in the case of ω = 4ωc3He(0) and of the optimization of the fusion yield in the case of lower electron density and higher electron temperature

Measurement of ICRF wave propagation using a microwave reflectometer with fast antenna switching on GAMMA 10

NASA Astrophysics Data System (ADS)

Ikezoe, R.; Ichimura, M.; Itagaki, J.; Hirata, M.; Sumida, S.; Jang, S.; Izumi, K.; Tanaka, A.; Sekine, R.; Kubota, Y.; Shima, Y.; Kohagura, J.; Yoshikawa, M.; Sakamoto, M.; Nakashima, Y.

2017-12-01

Slow Alfvén wave in ion cyclotron range of frequency (ICRF) is a powerful tool to heat ions confined in a mirror field. In spite of its efficient heating effect that has been attained in the central cell of GAMMA 10, there are still unknown characteristics concerning boundary condition, transient variation of heating effect, exact picture of cyclotron damping, and so on. To study these characteristics in detail, a multi-point measurement of the waves inside the hot plasma has been recently developed by using a microwave reflectometer. In addition to a radial profile measurement that is available by a usual reflectometer, an axial measurement has been achieved by arraying transmitting and receiving horn antennas in the axial direction, which are repeatedly switched in time during a discharge with PIN diode switches. Another transmitting and receiving horn antenna pair was newly added to the system and probing at five cross sections was achieved in a single discharge with time resolution of about 1 ms at each antenna pair position. With the upgraded reflectometer system, axial and radial distributions of wave-induced fluctuations and those temporal behavior were clearly observed, offering valuable data on wave physics in a hot mirror plasma.

Novel Reactor Relevant RF Actuator Schemes for the Lower Hybrid and the Ion Cyclotron Range of Frequencies

NASA Astrophysics Data System (ADS)

Bonoli, Paul

2014-10-01

This paper presents a fresh physics perspective on the onerous problem of coupling and successfully utilizing ion cyclotron range of frequencies (ICRF) and lower hybrid range of frequencies (LHRF) actuators in the harsh environment of a nuclear fusion reactor. The ICRF and LH launchers are essentially first wall components in a fusion reactor and as such will be subjected to high heat fluxes. The high field side (HFS) of the plasma offers a region of reduced heat flux together with a quiescent scrape off layer (SOL). Placement of the ICRF and LHRF launchers on the tokamak HFS also offers distinct physics advantages: The higher toroidal magnetic field makes it possible to couple faster phase velocity LH waves that can penetrate farther into the plasma core and be absorbed by higher energy electrons, thereby increasing the current drive efficiency. In addition, re-location of the LH launcher off the mid-plane (i.e., poloidal ``steering'') allows further control of the deposition location. Also ICRF waves coupled from the HFS couple strongly to mode converted ion Bernstein waves and ion cyclotron waves waves as the minority density is increased, thus opening the possibility of using this scheme for flow drive and pressure control. Finally the quiescent nature of the HFS scrape off layer should minimize the effects of RF wave scattering from density fluctuations. Ray tracing / Fokker Planck simulations will be presented for LHRF applications in devices such as the proposed Advanced Divertor Experiment (ADX) and extending to ITER and beyond. Full-wave simulations will also be presented which demonstrate the possible combinations of electron and ion heating via ICRF mode conversion. Work supported by the US DoE under Contract Numbers DE-FC02-01ER54648 and DE-FC02-99ER54512.

Multi-frequency ICRF diagnostic of Tokamak plasmas

NASA Astrophysics Data System (ADS)

Lafonteese, David James

This thesis explores the diagnostic possibilities of a fast wave-based method for measuring the ion density and temperature profiles of tokamak plasmas. In these studies fast waves are coupled to the plasma at frequencies at the second harmonic of the ion gyrofrequency, at which wave energy is absorbed by the finite-temperature ions. As the ion gyrofrequency is dependent upon the local magnetic field, which varies as l/R in a tokamak, this power absorption is radially localized. The simultaneous launching of multiple frequencies, all resonating at different plasma positions, allows local measurements of the ion density and temperature. To investigate the profile applications of wave damping measurements in a simulated tokamak, an inhouse slab-model ICRF code is developed. A variety of analysis methods are presented, and ion density and temperature profiles are reconstructed for hydrogen plasmas for the Electric Tokamak (ET) and ITER parameter spaces. These methods achieve promising results in simulated plasmas featuring bulk ion heating, off-axis RF heating, and density ramps. The experimental results of similar studies on the Electric Tokamak, a high aspect ratio (R/a = 5), low toroidal field (2.2 kG) device are then presented. In these studies, six fast wave frequencies were coupled using a single-strap, low-field-side antenna to ET plasmas. The frequencies were variable, and could be tuned to resonate at different radii for different experiments. Four magnetic pickup loops were used to measure of the toroidal component of the wave magnetic field. The expected greater eigenmode damping of center-resonant frequencies versus edge-resonant frequencies is consistently observed. Comparison of measured aspects of fast wave behavior in ET is made with the slab code predictions, which validate the code simulations under weakly-damped conditions. A density profile is measured for an ET discharge through analysis of the fast wave measurements, and is compared to an

Full-wave simulations of ICRF heating regimes in toroidal plasma with non-Maxwellian distribution functions

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

Bertelli, N.; Valeo, E. J.; Green, D. L.

At the power levels required for significant heating and current drive in magnetically-confined toroidal plasma, modification of the particle distribution function from a Maxwellian shape is likely (Stix 1975 Nucl. Fusion 15 737), with consequent changes in wave propagation and in the location and amount of absorption. In order to study these effects computationally, both the finite-Larmor-radius and the high-harmonic fast wave (HHFW), versions of the full-wave, hot-plasma toroidal simulation code TORIC (Brambilla 1999 Plasma Phys. Control. Fusion 41 1 and Brambilla 2002 Plasma Phys. Control. Fusion 44 2423), have been extended to allow the prescription of arbitrary velocity distributionsmore » of the form f(v(parallel to), v(perpendicular to) , psi, theta). For hydrogen (H) minority heating of a deuterium (D) plasma with anisotropic Maxwellian H distributions, the fractional H absorption varies significantly with changes in parallel temperature but is essentially independent of perpendicular temperature. On the other hand, for HHFW regime with anisotropic Maxwellian fast ion distribution, the fractional beam ion absorption varies mainly with changes in the perpendicular temperature. The evaluation of the wave-field and power absorption, through the full wave solver, with the ion distribution function provided by either a Monte-Carlo particle and Fokker-Planck codes is also examined for Alcator C-Mod and NSTX plasmas. Non-Maxwellian effects generally tend to increase the absorption with respect to the equivalent Maxwellian distribution.« less

Full-wave simulations of ICRF heating regimes in toroidal plasmas with non-Maxwellian distribution functions

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

Bertelli, N.; Valeo, E.J.; Green, D.L.

At the power levels required for significant heating and current drive in magnetically-confined toroidal plasma, modification of the particle distribution function from a Maxwellian shape is likely [T. H. Stix, Nucl. Fusion, 15 737 (1975)], with consequent changes in wave propagation and in the location and amount of absorption. In order to study these effects computationally, both the finite-Larmor-radius and the high-harmonic fast wave (HHFW), versions of the full-wave, hot-plasma toroidal simulation code TORIC [M. Brambilla, Plasma Phys. Control. Fusion 41, 1 (1999) and M. Brambilla, Plasma Phys. Control. Fusion 44, 2423 (2002)], have been extended to allow the prescriptionmore » of arbitrary velocity distributions of the form f(v||, v_perp, psi , theta). For hydrogen (H) minority heating of a deuterium (D) plasma with anisotropic Maxwellian H distributions, the fractional H absorption varies significantly with changes in parallel temperature but is essentially independent of perpendicular temperature. On the other hand, for HHFW regime with anisotropic Maxwellian fast ion distribution, the fractional beam ion absorption varies mainly with changes in the perpendicular temperature. The evaluation of the wave-field and power absorption, through the full wave solver, with the ion distribution function provided by either aMonte-Carlo particle and Fokker-Planck codes is also examined for Alcator C-Mod and NSTX plasmas. Non-Maxwellian effects generally tends to increase the absorption with respect to the equivalent Maxwellian distribution.« less

Full-wave simulations of ICRF heating regimes in toroidal plasma with non-Maxwellian distribution functions

NASA Astrophysics Data System (ADS)

Bertelli, N.; Valeo, E. J.; Green, D. L.; Gorelenkova, M.; Phillips, C. K.; Podestà, M.; Lee, J. P.; Wright, J. C.; Jaeger, E. F.

2017-05-01

At the power levels required for significant heating and current drive in magnetically-confined toroidal plasma, modification of the particle distribution function from a Maxwellian shape is likely (Stix 1975 Nucl. Fusion 15 737), with consequent changes in wave propagation and in the location and amount of absorption. In order to study these effects computationally, both the finite-Larmor-radius and the high-harmonic fast wave (HHFW), versions of the full-wave, hot-plasma toroidal simulation code TORIC (Brambilla 1999 Plasma Phys. Control. Fusion 41 1 and Brambilla 2002 Plasma Phys. Control. Fusion 44 2423), have been extended to allow the prescription of arbitrary velocity distributions of the form f≤ft({{v}\\parallel},{{v}\\bot},\\psi,θ \\right) . For hydrogen (H) minority heating of a deuterium (D) plasma with anisotropic Maxwellian H distributions, the fractional H absorption varies significantly with changes in parallel temperature but is essentially independent of perpendicular temperature. On the other hand, for HHFW regime with anisotropic Maxwellian fast ion distribution, the fractional beam ion absorption varies mainly with changes in the perpendicular temperature. The evaluation of the wave-field and power absorption, through the full wave solver, with the ion distribution function provided by either a Monte-Carlo particle and Fokker-Planck codes is also examined for Alcator C-Mod and NSTX plasmas. Non-Maxwellian effects generally tend to increase the absorption with respect to the equivalent Maxwellian distribution.

Full-wave simulations of ICRF heating regimes in toroidal plasma with non-Maxwellian distribution functions

DOE PAGES

Bertelli, N.; Valeo, E. J.; Green, D. L.; ...

2017-04-03

At the power levels required for significant heating and current drive in magnetically-confined toroidal plasma, modification of the particle distribution function from a Maxwellian shape is likely (Stix 1975 Nucl. Fusion 15 737), with consequent changes in wave propagation and in the location and amount of absorption. In order to study these effects computationally, both the finite-Larmor-radius and the high-harmonic fast wave (HHFW), versions of the full-wave, hot-plasma toroidal simulation code TORIC (Brambilla 1999 Plasma Phys. Control. Fusion 41 1 and Brambilla 2002 Plasma Phys. Control. Fusion 44 2423), have been extended to allow the prescription of arbitrary velocity distributionsmore » of the form f(v(parallel to), v(perpendicular to) , psi, theta). For hydrogen (H) minority heating of a deuterium (D) plasma with anisotropic Maxwellian H distributions, the fractional H absorption varies significantly with changes in parallel temperature but is essentially independent of perpendicular temperature. On the other hand, for HHFW regime with anisotropic Maxwellian fast ion distribution, the fractional beam ion absorption varies mainly with changes in the perpendicular temperature. The evaluation of the wave-field and power absorption, through the full wave solver, with the ion distribution function provided by either a Monte-Carlo particle and Fokker-Planck codes is also examined for Alcator C-Mod and NSTX plasmas. Non-Maxwellian effects generally tend to increase the absorption with respect to the equivalent Maxwellian distribution.« less

Study of ICRF wave propagation and plasma coupling efficiency in a linear magnetic mirror device

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

Peng, S.Y.

1991-07-01

Ion Cyclotron Range of Frequency (ICRF) wave propagation in an inhomogeneous axial magnetic field in a cylindrical plasma-vacuum system has historically been inadequately modelled. Previous works either sacrifice the cylindrical geometry in favor of a simpler slab geometry, concentrate on the resonance region, use a single mode to represent the entire field structure, or examine only radial propagation. This thesis performs both analytical and computational studies to model the ICRF wave-plasma coupling and propagation problem. Experimental analysis is also conducted to compare experimental results with theoretical predictions. Both theoretical as well as experimental analysis are undertaken as part of themore » thesis. The theoretical studies simulate the propagation of ICRF waves in an axially inhomogeneous magnetic field and in cylindrical geometry. Two theoretical analysis are undertaken - an analytical study and a computational study. The analytical study treats the inhomogeneous magnetic field by transforming the (r,z) coordinate into another coordinate system ({rho},{xi}) that allows the solution of the fields with much simpler boundaries. The plasma fields are then Fourier transformed into two coupled convolution-integral equations which are then differenced and solved for both the perpendicular mode number {alpha} as well as the complete EM fields. The computational study involves a multiple eigenmode computational analysis of the fields that exist within the plasma-vacuum system. The inhomogeneous axial field is treated by dividing the geometry into a series of transverse axial slices and using a constant dielectric tensor in each individual slice. The slices are then connected by longitudinal boundary conditions.« less

A Complete Bank of Optical Images of the ICRF QSOs

NASA Astrophysics Data System (ADS)

Humberto Andrei, Alexandre; Taris, Francois; Anton, Sonia; Bourda, Geraldine; Damljanovic, Goran; Souchay, Jean; Vieira Martins, Roberto; Pursimo, Tapio; Barache, Christophe; Nepomuceno da Silva Neto, Dario; Fernandes Coelho, Bruno David

2015-08-01

We have been developing a systematic effort to collect good quality images of the optical counterpart of ICRF sources, in particular for those that have been regularly radio surveyed either for future implementation at high frequencies and/or those that will be the link sources between the ICRF and the Gaia CRF. Observations have been taken at the LNA/Brazil, CASLEO/Argentina, NOT/Spain, LFOA/Austria, Rozhen/Bulgária, and ASV/Serbia. In complement images were collected from the SDSS. As a step to implement such image data bank and make it publicly available through the IERS service we present its description, that comprises for each source the number of measurements, filter, pixel scale, size of field, and seeing at each observation. The photometry analysis is centered on the morphology, since there remain still cases in which the host galaxy is overwhelming, and many cases in which the host asks for a non-stellar PSF modeling. On basis of the neighbor stars we assign magnitudes and variability whenever possible. Finally, assisted by previous literature, the redshift and luminosity are used to derive astrophysical quantities, in special the absolute magnitude, SED and spectral index. Moreover, since Gaia will not obtain direct images of the observed sources, the morphology and magnitude becomes useful as templates onto which assembling and interpreting the one-dimensional and uncontinuous line spread function samplings that will be delivered by Gaia for each QSO.

A folded waveguide ICRF antenna for PBX-M and TFTR

NASA Astrophysics Data System (ADS)

Bigelow, T. S.; Carter, M. D.; Fogelman, C. H.; Yugo, J. J.; Baity, F. W.; Bell, G. L.; Gardner, W. L.; Goulding, R. H.; Hoffman, D. J.; Ryan, P. M.; Swain, D. W.; Taylor, D. J.; Wilson, R.; Bernabei, S.; Kugel, H.; Ono, M.

1996-02-01

The folded waveguide (FWG) antenna is an advanced ICRF launcher under development at ORNL that offers many significant advantages over current-strap type antennas. These features are particularly beneficial for reactor-relevant applications such as ITER and TPX. Previous tests of a development folded waveguide with a low density plasma load have shown a factor of 5 increase in power capability over loop antennas into similar plasma conditions. The performance and reliability of a FWG with an actual tokamak plasma load must now be verified for further acceptance of this concept. A 58 MHz, 4 MW folded waveguide is being designed and built for the PBX-M and TFTR tokamaks at Princeton Plasma Physics Laboratory. This design has a square cross-section that can be installed as either a fast wave (FW) or ion-Bernstein wave (IBW) launcher by 90° rotation. Two new features of the design are: a shorter quarter-wavelength resonator configuration and a rear-feed input power coupling loop. Loading calculations with a standard shorting plate indicate that a launched power level of 4 MW is possible on either machine. Mechanical and disruption force analysis indicates that bolted construction will withstand the disruption loads. An experimental program is planned to characterize the plasma loading, heating effectiveness, power capability, impurity generation and other factors for both FW and IBW cases. High power tests of the new configuration are being performed with a development FWG unit on RFTF at ORNL.

Anisotropic distribution function of minority tail ions generated by strong ion-cyclotron resonance heating

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

Chang, C.S.; Colestock, P.

1989-05-01

The highly anisotropic particle distribution function of minority tail ions driven by ion-cyclotron resonance heating at the fundamental harmonic is calculated in a two-dimensional velocity space. It is assumed that the heating is strong enough to drive most of the resonant ions above the in-electron critical slowing-down energy. Simple analytic expressions for the tail distribution are obtained fro the case when the Doppler effect is sufficiently large to flatten the sharp pitch angle dependence in the bounce averaged qualilinear heating coefficient, D/sub b/, and for the case when D/sub b/ is assumed to be constant in pitch angle and energy.more » It is found that a simple constant-D/sub b/ solution can be used instead of the more complicated sharp-D/sub b/ solution for many analytic purposes. 4 refs., 4 figs.« less

A PIC-MCC code RFdinity1d for simulation of discharge initiation by ICRF antenna

NASA Astrophysics Data System (ADS)

Tripský, M.; Wauters, T.; Lyssoivan, A.; Bobkov, V.; Schneider, P. A.; Stepanov, I.; Douai, D.; Van Eester, D.; Noterdaeme, J.-M.; Van Schoor, M.; ASDEX Upgrade Team; EUROfusion MST1 Team

2017-12-01

Discharges produced and sustained by ion cyclotron range of frequency (ICRF) waves in absence of plasma current will be used on ITER for (ion cyclotron-) wall conditioning (ICWC, Te = 3{-}5 eV, ne < 1018 m-3 ). In this paper, we present the 1D particle-in-cell Monte Carlo collision (PIC-MCC) RFdinity1d for the study the breakdown phase of ICRF discharges, and its dependency on the RF discharge parameters (i) antenna input power P i , (ii) RF frequency f, (iii) shape of the electric field and (iv) the neutral gas pressure pH_2 . The code traces the motion of both electrons and ions in a narrow bundle of magnetic field lines close to the antenna straps. The charged particles are accelerated in the parallel direction with respect to the magnetic field B T by two electric fields: (i) the vacuum RF field of the ICRF antenna E_z^RF and (ii) the electrostatic field E_zP determined by the solution of Poisson’s equation. The electron density evolution in simulations follows exponential increase, {\\dot{n_e} ∼ ν_ion t } . The ionization rate varies with increasing electron density as different mechanisms become important. The charged particles are affected solely by the antenna RF field E_z^RF at low electron density ({ne < 1011} m-3 , {≤ft \\vert E_z^RF \\right \\vert \\gg ≤ft \\vert E_zP \\right \\vert } ). At higher densities, when the electrostatic field E_zP is comparable to the antenna RF field E_z^RF , the ionization frequency reaches the maximum. Plasma oscillations propagating toroidally away from the antenna are observed. The simulated energy distributions of ions and electrons at {ne ∼ 1015} m-3 correspond a power-law Kappa energy distribution. This energy distribution was also observed in NPA measurements at ASDEX Upgrade in ICWC experiments.

Reinstated JET ICRF ILA: Overview and Results

NASA Astrophysics Data System (ADS)

Dumortier, Pierre; Durodié, Frédéric; Blackman, Trevor; Helou, Walid; Jacquet, Philippe; Lerche, Ernesto; Monakhov, Igor; Noble, Craig; Bobkov, Volodymyr; Goulding, Richard; Kaufman, Michael; Van Eester, Dirk

2017-10-01

The works undertaken to reinstate the JET ICRF ILA are reviewed. The vacuum matching capacitors were replaced, an extensive calibration of all the measurements in the RF circuit was carried out, new simulation tools were created and new control algorithms were implemented for the - toroidal and poloidal - phase control of the array as well as for the matching of the second stage. A review of the contribution of the reinstated ILA to the JET programme during the last campaigns is given showing namely that the new controls allowed extending the range of the operation to lower (29MHz) and higher (51MHz) frequencies than previously achieved and allowed more flexible and reliable operation. Operation with coupled power levels up to 2.8MW and voltages up to 40kV was achieved. ILA results on plasma are discussed and emphasis is given to the features of interest for ITER.

Feedback control impedance matching system using liquid stub tuner for ion cyclotron heating

NASA Astrophysics Data System (ADS)

Nomura, G.; Yokota, M.; Kumazawa, R.; Takahashi, C.; Torii, Y.; Saito, K.; Yamamoto, T.; Takeuchi, N.; Shimpo, F.; Kato, A.; Seki, T.; Mutoh, T.; Watari, T.; Zhao, Y.

2001-10-01

A long pulse discharge more than 2 minutes was achieved using Ion Cyclotron Range of Frequency (ICRF) heating only on the Large Helical Device (LHD). The final goal is a steady state operation (30 minutes) at MW level. A liquid stub tuner was newly invented to cope with the long pulse discharge. The liquid surface level was shifted under a high RF voltage operation without breakdown. In the long pulse discharge the reflected power was observed to gradually increase. The shift of the liquid surface was thought to be inevitably required at the further longer discharge. An ICRF heating system consisting of a liquid stub tuner was fabricated to demonstrate a feedback control impedance matching. The required shift of the liquid surface was predicted using a forward and a reflected RF powers as well as the phase difference between them. A liquid stub tuner was controlled by the multiprocessing computer system with CINOS (CHS Integration No Operating System) methods. The prime objective was to improve the performance of data processing and controlling a signal response. By employing this method a number of the program steps was remarkably reduced. A real time feedback control was demonstrated in the system using a temporally changed electric resistance.

ICRF antenna-plasma interactions and its influence on W sputtering in ASDEX upgrade

NASA Astrophysics Data System (ADS)

ASDEX Upgrade Team Bobkov, Vl.; Braun, F.; Colas, L.; Dux, R.; Faugel, H.; Giannone, L.; Herrmann, A.; Kallenbach, A.; Müller, H. W.; Neu, R.; Noterdaeme, J.-M.; Pütterich, Th.; Siegl, G.; Wolfrum, E.

2011-08-01

Analysis of the W concentration during ICRF over AUG experimental campaigns confirms the critical role of W antenna limiters for the W content in plasma, though other structures connected to antennas along magnetic field lines cannot be neglected as W sources.Abrupt changes of spectroscopically measured W sputtering patterns are observed which correlate with step-wise changes of connection lengths at antenna limiters. Analysis of discharges with the reversed direction of toroidal magnetic field shows less W release compared to identical discharges with the normal direction. The lower W release is accompanied by lower intensity of fluctuations of reflected ICRF power in the 1-60 kHz range. The observations suggest that local magnetic geometry and density convection at the antennas are at least as important for the W sputtering as the distribution of RF near-fields at the antenna.Measurements of DC currents flowing through the antenna limiters show that the limiters at the active antenna collect predominantly negative DC currents whereas those distant from the active antenna collect predominantly positive DC currents. The latter decrease and become more negative when the intensity of the RF pickup measured at the limiters increases. The mutual compensation between the positive and negative currents can lead to lower values of the DC current than those expected from simplified theoretical models of the RF/DC circuit.

ICRF antenna-plasma interactions and its influence on W sputtering in ASDEX upgrade

NASA Astrophysics Data System (ADS)

Bobkov, Vl.; Braun, F.; Colas, L.; Dux, R.; Faugel, H.; Giannone, L.; Herrmann, A.; Kallenbach, A.; Müller, H. W.; Neu, R.; Noterdaeme, J.-M.; Pütterich, Th.; Siegl, G.; Wolfrum, E.; ASDEX Upgrade Team

2011-08-01

Analysis of the W concentration during ICRF over AUG experimental campaigns confirms the critical role of W antenna limiters for the W content in plasma, though other structures connected to antennas along magnetic field lines cannot be neglected as W sources. Abrupt changes of spectroscopically measured W sputtering patterns are observed which correlate with step-wise changes of connection lengths at antenna limiters. Analysis of discharges with the reversed direction of toroidal magnetic field shows less W release compared to identical discharges with the normal direction. The lower W release is accompanied by lower intensity of fluctuations of reflected ICRF power in the 1-60 kHz range. The observations suggest that local magnetic geometry and density convection at the antennas are at least as important for the W sputtering as the distribution of RF near-fields at the antenna. Measurements of DC currents flowing through the antenna limiters show that the limiters at the active antenna collect predominantly negative DC currents whereas those distant from the active antenna collect predominantly positive DC currents. The latter decrease and become more negative when the intensity of the RF pickup measured at the limiters increases. The mutual compensation between the positive and negative currents can lead to lower values of the DC current than those expected from simplified theoretical models of the RF/DC circuit.

Theory and Practice in ICRF Antennas for Long Pulse Operation

NASA Astrophysics Data System (ADS)

Colas, L.; Faudot, E.; Brémond, S.; Heuraux, S.; Mitteau, R.; Chantant, M.; Goniche, M.; Basiuk, V.; Bosia, G.; Tore Supra Team

2005-09-01

Long plasma discharges on the Tore Supra (TS) tokamak were extended in 2004 towards higher powers and plasma densities by combined Lower Hybrid (LH) and Ion Cyclotron Range of Frequencies (ICRF) waves. RF pulses of 20s×8MW and 60s×4MW were produced. TS is equipped with 3 ICRF antennas, whose front faces are ready for CW operation. This paper reports on their behaviour over high power long pulses, as observed with infrared (IR) thermography and calorimetric measurements. Edge parasitic losses, although modest, are concentrated on a small surface and can raise surface temperatures close to operational limits. A complex hot spot pattern was revealed with at least 3 physical processes involved : convected power, electron acceleration in the LH near field, and a RF-specific phenomenon compatible with RF sheaths. LH coupling was also perturbed in the antenna shadow. This was attributed to RF-induced DC E×B0 convection. This motivated sheath modelling in two directions. First, the 2D topology of RF potentials was investigated in relation with the RF current distribution over the antenna, via a Green's function formalism and full-wave calculation using the ICANT code. In front of phased arrays of straps, convective cells were interpreted using the RF current profiles of strip line theory. Another class of convective cells, specific to antenna box corners, was evidenced for the first time. Within 1D sheath models assuming independent flux tubes, RF and rectified DC potentials are proportional. 2D fluid models couple nearby flux tubes via transverse polarisation currents. Unexpectedly this does not necessarily smooth RF potential maps. Peak DC potentials can even be enhanced. The experience gained on TS and the numerical tools are valuable for designing steady state high power antennas for next step devices. General rules to reduce RF potentials as well as concrete design options are discussed.

Extending the ICRF into the Infrared: 2MASS - UCAC Astrometry

NASA Technical Reports Server (NTRS)

Zacharias, Norbert; McCallon, Howard L.; Kopan, Eugene; Cutri, Roc M.

2000-01-01

An external comparison between the infrared 2MASS and the optical UCAC positions was performed, both being on the same system, the ICRS. About 48 million sources in common were identified. Random errors of the 2MASS catalog positions are about 60 to 70 mas per coordinate for the Ks = 4 to 14 range, increasing to about 100 to 150 mas for saturated and very faint stars. Systematic position differences between the 2 catalogs are very small, about 5 to 10 mas as a function of magnitude and color, with somewhat larger errors as a function of right ascension and declination. The extension of the ICRF into the infrared has become a reality.

Production of Internal Transport Barriers via self-generated flows in Alcator C-Mod

NASA Astrophysics Data System (ADS)

Fiore, Catherine L.

2011-10-01

New results suggest that changes observed in the intrinsic toroidal rotation influence ITB formation in Alcator C-Mod that arise when the resonance for ICRF minority heating is positioned off-axis at or outside of the plasma half-radius. These ITBs form in a reactor relevant regime, without particle or momentum injection, with Ti ~Te, and with monotonic q profiles (qmin < 1). C-Mod H-mode plasmas exhibit strong intrinsic co-current rotation that increases with increasing stored energy without external drive. With the resonance position off-axis, the rotation decreases in the center of the plasma resulting in a radial rotation profile with a central well which deepens and moves farther off-axis when the ICRF resonance is at the plasma half-radius. This profile results in strong ExB shear (>1.5x105 Rad/sec) in the region where the ITB foot is observed. The self generated ExB shearing increases rapidly after the H-mode transition in off-axis ICRF heated discharges, before other profile changes are observed. Gyrokinetic analyses indicate that this spontaneous shearing rate is comparable to the linear ITG growth rate at the ITB location and may be responsible for stabilizing the underlying turbulence. Detailed measurement of the ion temperature demonstrates that the radial profile also flattens as the ICRF resonance position moves off axis. This decreases R/LTi in the barrier region, lessening the drive for the ITG turbulence and the resulting particle transport. The reduction in particle transport resulting from increase in core stability allows the neoclassical pinch to peak the density and pressure on axis. This suggests that spontaneous rotation is a potential tool for plasma profile control in reactor plasmas. The experimental results and corresponding gyrokinetic study will be presented. US-DoE DE-FC02-99ER54512 and DE-FG03-96ER54373.

SIDON: A simulator of radio-frequency networks. Application to WEST ICRF launchers

NASA Astrophysics Data System (ADS)

Helou, Walid; Dumortier, Pierre; Durodié, Frédéric; Goniche, Marc; Hillairet, Julien; Mollard, Patrick; Berger-By, Gilles; Bernard, Jean-Michel; Colas, Laurent; Lombard, Gilles; Maggiora, Riccardo; Magne, Roland; Milanesio, Daniele; Moreau, Didier

2015-12-01

SIDON (SImulator of raDiO-frequency Networks) is an in-house developed Radio-Frequency (RF) network solver that has been implemented to cross-validate the design of WEST ICRF launchers and simulate their impedance matching algorithm while considering all mutual couplings and asymmetries. In this paper, the authors illustrate the theory of SIDON as well as results of its calculations. The authors have built time-varying plasma scenarios (a sequence of launchers front-faces L-mode and H-mode Z-matrices), where at each time step (1 millisecond here), SIDON solves the RF network. At the same time, when activated, the impedance matching algorithm controls the matching elements (vacuum capacitors) and thus their corresponding S-matrices. Typically a 1-second pulse requires around 10 seconds of computational time on a desktop computer. These tasks can be hardly handled by commercial RF software. This innovative work allows identifying strategies for the launchers future operation while insuring the limitations on the currents, voltages and electric fields, matching and Load-Resilience, as well as the required straps voltage amplitude/phase balance. In this paper, a particular attention is paid to the simulation of the launchers behavior when arcs appear at several locations of their circuits using SIDON calculator. This latter work shall confirm or identify strategies for the arc detection using various RF electrical signals. One shall note that the use of such solvers in not limited to ICRF launchers simulations but can be employed, in principle, to any linear or linearized RF problem.

RF current distribution and topology of RF sheath potentials in front of ICRF antennae

NASA Astrophysics Data System (ADS)

Colas, L.; Heuraux, S.; Brémond, S.; Bosia, G.

2005-08-01

The 2D (radial/poloidal) spatial topology of RF-induced convective cells developing radially in front of ion cyclotron range of frequency (ICRF) antennae is investigated, in relation to the spatial distribution of RF currents over the metallic structure of the antenna. This is done via a Green's function, determined from the ICRF wave coupling equations, and well-suited to open field lines extending toroidally far away on both sides of the antenna. Using such formalism, combined with a full-wave calculation using the 3D antenna code ICANT (Pécoul S. et al 2000 Comput. Phys. Commun. 146 166-87), two classes of convective cells are analysed. The first one appears in front of phased arrays of straps, and depending on the strap phasing, its topology is interpreted using the poloidal profiles of either the RF current or the RF voltage of the strip line theory. The other class of convective cells is specific to antenna box corners and is evidenced for the first time. Based on such analysis, general design rules are worked out in order to reduce the RF-sheath potentials, which generalize those proposed in the earlier literature, and concrete antenna design options are tested numerically. The merits of aligning all strap centres on the same (tilted) flux tube, and of reducing the antenna box toroidal conductivity in its lower and upper parts, are discussed.

Heating performances of a IC in-blanket ring array

NASA Astrophysics Data System (ADS)

Bosia, G.; Ragona, R.

2015-12-01

An important limiting factor to the use of ICRF as candidate heating method in a commercial reactor is due to the evanescence of the fast wave in vacuum and in most of the SOL layer, imposing proximity of the launching structure to the plasma boundary and causing, at the highest power level, high RF standing and DC rectified voltages at the plasma periphery, with frequent voltage breakdowns and enhanced local wall loading. In a previous work [1] the concept for an Ion Cyclotron Heating & Current Drive array (and using a different wave guide technology, a Lower Hybrid array) based on the use of periodic ring structure, integrated in the reactor blanket first wall and operating at high input power and low power density, was introduced. Based on the above concept, the heating performance of such array operating on a commercial fusion reactor is estimated.

Heating performances of a IC in-blanket ring array

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

Bosia, G., E-mail: gbosia@to.infn.it; Ragona, R.

2015-12-10

An important limiting factor to the use of ICRF as candidate heating method in a commercial reactor is due to the evanescence of the fast wave in vacuum and in most of the SOL layer, imposing proximity of the launching structure to the plasma boundary and causing, at the highest power level, high RF standing and DC rectified voltages at the plasma periphery, with frequent voltage breakdowns and enhanced local wall loading. In a previous work [1] the concept for an Ion Cyclotron Heating & Current Drive array (and using a different wave guide technology, a Lower Hybrid array) basedmore » on the use of periodic ring structure, integrated in the reactor blanket first wall and operating at high input power and low power density, was introduced. Based on the above concept, the heating performance of such array operating on a commercial fusion reactor is estimated.« less

Theory and Practice in ICRF Antennas for Long Pulse Operation

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

Colas, L.; Bremond, S.; Mitteau, R.

2005-09-26

Long plasma discharges on the Tore Supra (TS) tokamak were extended in 2004 towards higher powers and plasma densities by combined Lower Hybrid (LH) and Ion Cyclotron Range of Frequencies (ICRF) waves. RF pulses of 20sx8MW and 60sx4MW were produced. TS is equipped with 3 ICRF antennas, whose front faces are ready for CW operation. This paper reports on their behaviour over high power long pulses, as observed with infrared (IR) thermography and calorimetric measurements. Edge parasitic losses, although modest, are concentrated on a small surface and can raise surface temperatures close to operational limits. A complex hot spot patternmore » was revealed with at least 3 physical processes involved : convected power, electron acceleration in the LH near field, and a RF-specific phenomenon compatible with RF sheaths. LH coupling was also perturbed in the antenna shadow. This was attributed to RF-induced DC ExB0 convection. This motivated sheath modelling in two directions. First, the 2D topology of RF potentials was investigated in relation with the RF current distribution over the antenna, via a Green's function formalism and full-wave calculation using the ICANT code. In front of phased arrays of straps, convective cells were interpreted using the RF current profiles of strip line theory. Another class of convective cells, specific to antenna box corners, was evidenced for the first time. Within 1D sheath models assuming independent flux tubes, RF and rectified DC potentials are proportional. 2D fluid models couple nearby flux tubes via transverse polarisation currents. Unexpectedly this does not necessarily smooth RF potential maps. Peak DC potentials can even be enhanced. The experience gained on TS and the numerical tools are valuable for designing steady state high power antennas for next step devices. General rules to reduce RF potentials as well as concrete design options are discussed.« less

OPTICAL SPECTRA OF CANDIDATE INTERNATIONAL CELESTIAL REFERENCE FRAME (ICRF) FLAT-SPECTRUM RADIO SOURCES

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

Titov, O.; Stanford, Laura M.; Johnston, Helen M.

2013-07-01

Continuing our program of spectroscopic observations of International Celestial Reference Frame (ICRF) sources, we present redshifts for 120 quasars and radio galaxies. Data were obtained with five telescopes: the 3.58 m European Southern Observatory New Technology Telescope, the two 8.2 m Gemini telescopes, the 2.5 m Nordic Optical Telescope (NOT), and the 6.0 m Big Azimuthal Telescope of the Special Astrophysical Observatory in Russia. The targets were selected from the International VLBI Service for Geodesy and Astrometry candidate International Celestial Reference Catalog which forms part of an observational very long baseline interferometry (VLBI) program to strengthen the celestial reference frame.more » We obtained spectra of the potential optical counterparts of more than 150 compact flat-spectrum radio sources, and measured redshifts of 120 emission-line objects, together with 19 BL Lac objects. These identifications add significantly to the precise radio-optical frame tie to be undertaken by Gaia, due to be launched in 2013, and to the existing data available for analyzing source proper motions over the celestial sphere. We show that the distribution of redshifts for ICRF sources is consistent with the much larger sample drawn from Faint Images of the Radio Sky at Twenty cm (FIRST) and Sloan Digital Sky Survey, implying that the ultra-compact VLBI sources are not distinguished from the overall radio-loud quasar population. In addition, we obtained NOT spectra for five radio sources from the FIRST and NRAO VLA Sky Survey catalogs, selected on the basis of their red colors, which yielded three quasars with z > 4.« less

RF current profile control studies in the alcator C-mod tokamak

NASA Astrophysics Data System (ADS)

Bonoli, P. T.; Porkolab, M.; Wukitch, S. J.; Bernabei, S.; Kaita, R.; Mikkelsen, D.; Phillips, C. K.; Schilling, G.

1999-09-01

Time dependent calculations of lower hybrid (LH) current profile control in Alcator C-Mod have been done using the TRANSP [1], FPPRF [2], and LSC [3] codes. Up to 3 MW of LH current drive power was applied in plasmas with high power ICRF minority heating (PICH=1.8-3 MW) and fast current ramp up. Using the experimentally measured temperature profiles, off-axis current generation resulted in nonmonotonic q-profiles with qmin~=1.6. Self-consistent effects of off-axis electron heating by the LH power were also included in the analysis and significant broadening of the electron temperature profile was found with qmin>~2 and a larger shear reversal radius.

Ohmic ITBs in Alcator C-Mod

NASA Astrophysics Data System (ADS)

Rowan, William L.; Bespamyatnov, Igor O.; Fiore, C. L.; Dominguez, A.; Hubbard, A. E.; Ince-Cushman, A.; Greenwald, M. J.; Lin, L.; Marmar, E. S.; Reinke, M.; Rice, J. E.; Zhurovich, K.

2007-11-01

Internal transport barrier (ITB) plasmas can arise spontaneously in Ohmic Alcator C-Mod plasmas. The operational prescription for the ITB include formation of an EDA H-mode in a toroidal magnetic field that is ramping down and a subsequent increase in the toroidal magnetic field. Like ITBs generated with off-axis ICRF heating, these have peaked pressure profiles which can be suppressed by on-axis ICRF heating. Recent work on onset conditions for the ICRF generated ITB (K. Zhurovich, et al., To be published in Nuclear Fusion) demonstrates that the broadening of the ion temperature profile due to off-axis ICRF reduces the ion temperature gradient and suppreses the ITG instability driven particle flux as the primary mechanism for ITB formation. The object of this study is to examine the characteristics of Ohmic ITBs to find whether this model for onset is supported.

Effect of the scrape-off layer in AORSA full wave simulations of fast wave minority, mid/high harmonic, and helicon heating regimes

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

Bertelli, N., E-mail: nbertell@pppl.gov; Gerhardt, S.; Hosea, J. C.

2015-12-10

Several experiments on different machines and in different fast wave (FW) heating regimes, such as hydrogen minority heating and high harmonic fast waves, have found strong interactions between radio-frequency (RF) waves and the scrape-off layer (SOL) region. This paper examines the propagation and the power loss in the SOL by using the full wave code AORSA, in which the edge plasma beyond the last closed flux surface (LCFS) is included in the solution domain and a collisional damping parameter is used as a proxy to represent the real, and most likely nonlinear, damping processes. 3D AORSA results for the Nationalmore » Spherical Torus eXperiment (NSTX), where a full antenna spectrum is reconstructed, are shown, confirming the same behavior found for a single toroidal mode results in Bertelli et al, Nucl. Fusion, 54 083004, 2014, namely, a strong transition to higher SOL power losses (driven by the RF field) when the FW cut-off is moved away from in front of the antenna by increasing the edge density. Additionally, full wave simulations have been extended to “conventional” tokamaks with higher aspect ratios, such as the DIII-D, Alcator C-Mod, and EAST devices. DIII-D results show similar behavior found in NSTX and NSTX-U, consistent with previous DIII-D experimental observations. In contrast, a different behavior has been found for Alcator C-Mod and EAST, which operate in the minority heating regime unlike NSTX/NSTX-U and DIII-D, which operate in the mid/high harmonic regime. A substantial discussion of some of the main aspects, such as (i) the pitch angle of the magnetic field; (ii) minority heating vs. mid/high harmonic regimes is presented showing the different behavior of the RF field in the SOL region for NSTX-U scenarios with different plasma current. Finally, the preliminary results of the impact of the SOL region on the evaluation of the helicon current drive efficiency in DIII-D is presented for the first time and briefly compared with the different

Effect of the scrape-off layer in AORSA full wave simulations of fast wave minority, mid/high harmonic, and helicon heating regimes

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

Bertelli, Nicola; Jaeger, E. F.; Lau, Cornwall H

2015-01-01

Several experiments on different machines and in different fast wave (FW) heating regimes, such as hydrogen minority heating and high harmonic fast waves, have found strong interactions between radio-frequency (RF) waves and the scrape-off layer (SOL) region. This paper examines the propagation and the power loss in the SOL by using the full wave code AORSA, in which the edge plasma beyond the last closed flux surface (LCFS) is included in the solution domain and a collisional damping parameter is used as a proxy to represent the real, and most likely nonlinear, damping processes. 3D AORSA results for the Nationalmore » Spherical Torus eXperiment (NSTX), where a full antenna spectrum is reconstructed, are shown, confirming the same behavior found for a single toroidal mode results in Bertelli et al, Nucl. Fusion, 54 083004, 2014, namely, a strong transition to higher SOL power losses (driven by the RF field) when the FW cut-off is moved away from in front of the antenna by increasing the edge density. Additionally, full wave simulations have been extended to "conventional" tokamaks with higher aspect ratios, such as the DIII-D, Alcator C-Mod, and EAST devices. DIII-D results show similar behavior found in NSTX and NSTX-U, consistent with previous DIII-D experimental observations. In contrast, a different behavior has been found for Alcator C-Mod and EAST, which operate in the minority heating regime unlike NSTX/NSTX-U and DIII-D, which operate in the mid/high harmonic regime. A substantial discussion of some of the main aspects, such as (i) the pitch angle of the magnetic field; (ii) minority heating vs. mid/high harmonic regimes is presented showing the different behavior of the RF field in the SOL region for NSTX-U scenarios with different plasma current. Finally, the preliminary results of the impact of the SOL region on the evaluation of the helicon current drive efficiency in DIII-D is presented for the first time and briefly compared with the different

Prospects for Alpha Particle Heating in JET in the Hot Ion Regime

NASA Astrophysics Data System (ADS)

Cordey, J. G.; Keilhacker, M.; Watkins, M. L.

1987-01-01

The prospects for alpha particle heating in JET are discussed. A computational model is developed to represent adequately the neutron yield from JET plasmas heated by neutral beam injection. This neutral beam model, augmented by a simple plasma model, is then used to determine the neutron yields and fusion Q-values anticipated for different heating schemes in future operation of JET with tritium. The relative importance of beam-thermal and thermal-thermal reactions is pointed out and the dependence of the results on, for example, plasma density, temperature, energy confinement and purity is shown. Full 1½-D transport code calculations, based on models developed for ohmic, ICRF and NBI heated JET discharges, are used also to provide a power scan for JET operation in tritium in the low density, high ion temperature regime. The results are shown to be in good agreement with the estimates made using the simple plasma model and indicate that, based on present knowledge, a fusion Q-value in the plasma centre above unity should be achieved in JET.

First observations of minority ion (H+) structuring in stimulated radiation during second electron gyroharmonic heating experiments

NASA Astrophysics Data System (ADS)

Bordikar, M. R.; Scales, W. A.; Samimi, A. R.; Bernhardt, P. A.; Brizcinski, S.; McCarrick, M. J.

2013-04-01

This work presents the first observations of unique narrowband emissions ordered near the hydrogen ion (H+) gyrofrequency (fcH) in the stimulated electromagnetic emission spectrum when the transmitter is tuned near the second electron gyroharmonic frequency (2fce) during ionospheric modification experiments. The frequency structuring of these newly discovered emission lines is quite unexpected since H+ is known to be a minor constituent in the interaction region which is near 160 km altitude. The spectral lines are typically shifted from the pump wave frequency by harmonics of a frequency about 10% less than fcH (≈ 800 Hz) and have a bandwidth of less than 50 Hz which is near the O+ gyrofrequency fcO. A theory is proposed to explain these emissions in terms of a parametric decay instability in a multi-ion species plasma due to possible proton precipitation associated with the disturbed conditions during the heating experiment. The observations can be explained by including several percent H+ ions into the background plasma. The implications are new possibilities for characterizing proton precipitation events during ionospheric heating experiments.

An optimization methodology for heterogeneous minor actinides transmutation

NASA Astrophysics Data System (ADS)

Kooyman, Timothée; Buiron, Laurent; Rimpault, Gérald

2018-04-01

In the case of a closed fuel cycle, minor actinides transmutation can lead to a strong reduction in spent fuel radiotoxicity and decay heat. In the heterogeneous approach, minor actinides are loaded in dedicated targets located at the core periphery so that long-lived minor actinides undergo fission and are turned in shorter-lived fission products. However, such targets require a specific design process due to high helium production in the fuel, high flux gradient at the core periphery and low power production. Additionally, the targets are generally manufactured with a high content in minor actinides in order to compensate for the low flux level at the core periphery. This leads to negative impacts on the fuel cycle in terms of neutron source and decay heat of the irradiated targets, which penalize their handling and reprocessing. In this paper, a simplified methodology for the design of targets is coupled with a method for the optimization of transmutation which takes into account both transmutation performances and fuel cycle impacts. The uncertainties and performances of this methodology are evaluated and shown to be sufficient to carry out scoping studies. An illustration is then made by considering the use of moderating material in the targets, which has a positive impact on the minor actinides consumption but a negative impact both on fuel cycle constraints (higher decay heat and neutron) and on assembly design (higher helium production and lower fuel volume fraction). It is shown that the use of moderating material is an optimal solution of the transmutation problem with regards to consumption and fuel cycle impacts, even when taking geometrical design considerations into account.

Characterization and Computational Modeling of Minor Phases in Alloy LSHR

NASA Technical Reports Server (NTRS)

Jou, Herng-Jeng; Olson, Gregory; Gabb, Timothy; Garg, Anita; Miller, Derek

2012-01-01

The minor phases of powder metallurgy disk superalloy LSHR were studied. Samples were consistently heat treated at three different temperatures for long times to approach equilibrium. Additional heat treatments were also performed for shorter times, to assess minor phase kinetics in non-equilibrium conditions. Minor phases including MC carbides, M23C6 carbides, M3B2 borides, and sigma were identified. Their average sizes and total area fractions were determined. CALPHAD thermodynamics databases and PrecipiCalc(TradeMark), a computational precipitation modeling tool, were employed with Ni-base thermodynamics and diffusion databases to model and simulate the phase microstructural evolution observed in the experiments with an objective to identify the model limitations and the directions of model enhancement.

TOPICA: an accurate and efficient numerical tool for analysis and design of ICRF antennas

NASA Astrophysics Data System (ADS)

Lancellotti, V.; Milanesio, D.; Maggiora, R.; Vecchi, G.; Kyrytsya, V.

2006-07-01

The demand for a predictive tool to help in designing ion-cyclotron radio frequency (ICRF) antenna systems for today's fusion experiments has driven the development of codes such as ICANT, RANT3D, and the early development of TOPICA (TOrino Polytechnic Ion Cyclotron Antenna) code. This paper describes the substantive evolution of TOPICA formulation and implementation that presently allow it to handle the actual geometry of ICRF antennas (with curved, solid straps, a general-shape housing, Faraday screen, etc) as well as an accurate plasma description, accounting for density and temperature profiles and finite Larmor radius effects. The antenna is assumed to be housed in a recess-like enclosure. Both goals have been attained by formally separating the problem into two parts: the vacuum region around the antenna and the plasma region inside the toroidal chamber. Field continuity and boundary conditions allow formulating of a set of two coupled integral equations for the unknown equivalent (current) sources; then the equations are reduced to a linear system by a method of moments solution scheme employing 2D finite elements defined over a 3D non-planar surface triangular-cell mesh. In the vacuum region calculations are done in the spatial (configuration) domain, whereas in the plasma region a spectral (wavenumber) representation of fields and currents is adopted, thus permitting a description of the plasma by a surface impedance matrix. Owing to this approach, any plasma model can be used in principle, and at present the FELICE code has been employed. The natural outcomes of TOPICA are the induced currents on the conductors (antenna, housing, etc) and the electric field in front of the plasma, whence the antenna circuit parameters (impedance/scattering matrices), the radiated power and the fields (at locations other than the chamber aperture) are then obtained. An accurate model of the feeding coaxial lines is also included. The theoretical model and its TOPICA

Production of internal transport barriers via self-generated mean flows in Alcator C-Moda)

NASA Astrophysics Data System (ADS)

Fiore, C. L.; Ernst, D. R.; Podpaly, Y. A.; Mikkelsen, D.; Howard, N. T.; Lee, Jungpyo; Reinke, M. L.; Rice, J. E.; Hughes, J. W.; Ma, Y.; Rowan, W. L.; Bespamyatnov, I.

2012-05-01

New results suggest that changes observed in the intrinsic toroidal rotation influence the internal transport barrier (ITB) formation in the Alcator C-Mod tokamak [E. S. Marmar and Alcator C-Mod group, Fusion Sci. Technol. 51, 261 (2007)]. These arise when the resonance for ion cyclotron range of frequencies (ICRF) minority heating is positioned off-axis at or outside of the plasma half-radius. These ITBs form in a reactor relevant regime, without particle or momentum injection, with Ti ≈ Te, and with monotonic q profiles (qmin < 1). C-Mod H-mode plasmas exhibit strong intrinsic co-current rotation that increases with increasing stored energy without external drive. When the resonance position is moved off-axis, the rotation decreases in the center of the plasma resulting in a radial toroidal rotation profile with a central well which deepens and moves farther off-axis when the ICRF resonance location reaches the plasma half-radius. This profile results in strong E × B shear (>1.5 × 105 rad/s) in the region where the ITB foot is observed. Gyrokinetic analyses indicate that this spontaneous shearing rate is comparable to the linear ion temperature gradient (ITG) growth rate at the ITB location and is sufficient to reduce the turbulent particle and energy transport. New and detailed measurement of the ion temperature demonstrates that the radial profile flattens as the ICRF resonance position moves off axis, decreasing the drive for the ITG the instability as well. These results are the first evidence that intrinsic rotation can affect confinement in ITB plasmas.

ORNL diagnostic and modeling development for LAPD ICRF experiments

NASA Astrophysics Data System (ADS)

Isler, R. C.; Caughman, J. B. O.; Lau, C.; Martin, E. H.; Perkins, R. J.; Compernolle, B. Van; Vincena, S.; Tripathi, S. K. P.; Gekelman, W.

2017-10-01

PPPL, UCLA, and ORNL scientists have recently collaborated on a three week ICRF campaign at the upgraded LAPD device to study near field-plasma interactions associated with a single strap antenna driven at 2.38 MHz with 100 kW of RF power. This poster highlights ORNL involvement through implementation of the following diagnostics: an optical emission probe to measure neutral density, a retarding field energy analyzer to measure fast ions, phase locked imaging to measure line integrated RF-driven optical emission fluctuations, and an RF compensated triple Langmuir probe to measure density and temperature. To interpret the results of the experimental campaign a 3D cold plasma finite element model with realistic antenna and vacuum vessel geometry was developed in COMSOL. A summary of these results will be discussed. Highlights include a proof of principle localized and spatially resolved measurement of the neutral density, a strong increase in RF-driven optical emission fluctuations directly in front of the RF antenna strap, a shift in fast ion energies near the plasma edge, and qualitative agreement between the COMSOL cold plasma model with the various diagnostics. Funded by the DOE OFES (DE-AC05-00OR22725, DE-AC02-09CH11466, and DE-FC02-07ER54918) and the Univ. of California (12-LR-237124).

Formation of Minor Phases in a Nickel-Based Disk Superalloy

NASA Technical Reports Server (NTRS)

Gabb, T. P.; Garg, A.; Miller, D. R.; Sudbrack, C. K.; Hull, D. R.; Johnson, D.; Rogers, R. B.; Gayda, J.; Semiatin, S. L.

2012-01-01

The minor phases of powder metallurgy disk superalloy LSHR were studied. Samples were consistently heat treated at three different temperatures for long times to approximate equilibrium. Additional heat treatments were also performed for shorter times, to then assess non-equilibrium conditions. Minor phases including MC carbides, M23C6 carbides, M3B2 borides, and sigma were identified. Their transformation temperatures, lattice parameters, compositions, average sizes and total area fractions were determined, and compared to estimates of an existing phase prediction software package. Parameters measured at equilibrium sometimes agreed reasonably well with software model estimates, with potential for further improvements. Results for shorter times representing non-equilibrium indicated significant potential for further extension of the software to such conditions, which are more commonly observed during heat treatments and service at high temperatures for disk applications.

Radio structure effects on the optical and radio representations of the ICRF

NASA Astrophysics Data System (ADS)

Andrei, A. H.; da Silva Neto, D. N.; Assafin, M.; Vieira Martins, R.

Silva Neto et al. (2002) show that comparing the ICRF Ext.1 sources standard radio position (Ma et al. 1998) against their optical counterpart position (Zacharias et al. 1999, Monet et al., 1998), a systematic pattern appears, which depends on the radio structure index (Fey and Charlot, 2000). The optical to radio offsets produce a distribution suggestive of a coincidence of the optical and radio centroids worse for the radio extended than for the radio compact sources. On average, the coincidence between the optical and radio centroids is found 7.9±1.1 mas smaller for the compact than for the extended sources. Such an effect is reasonably large, and certainly much too large to be due to errors on the VLBI radio position. On the other hand, it is too small to be accounted to the errors on the optical position, which moreover should be independent from the radio stucture. Thus, other than a true pattern of centroids non-coincidence, the remaining explanation is of a hazard result. This paper summarizes the several statistical tests used to discard the hazard explanation.

Full wave simulations of fast wave efficiency and power losses in the scrape-off layer of tokamak plasmas in mid/high harmonic and minority heating regimes

DOE PAGES

Bertelli, N.; Jaeger, E. F.; Hosea, J. C.; ...

2015-12-17

Here, several experiments on different machines and in different fast wave (FW) heating regimes, such as hydrogen minority heating and high harmonic fast waves (HHFW), have found strong interaction between radio-frequency (RF) waves and the scrape-off layer (SOL) region. This paper examines the propagation and the power loss in the SOL by using the full wave code AORSA, in which the edge plasma beyond the last closed flux surface (LCFS) is included in the solution domain and a collisional damping parameter is used as a proxy to represent the real, and most likely nonlinear, damping processes. 2D and 3D AORSAmore » results for the National Spherical Torus eXperiment (NSTX) have shown a strong transition to higher SOL power losses (driven by the RF field) when the FW cut-off is removed from in front of the antenna by increasing the edge density. Here, full wave simulations have been extended for 'conventional' tokamaks with higher aspect ratios, such as the DIII-D, Alcator C-Mod, and EAST devices. DIII-D results in HHFW regime show similar behavior found in NSTX and NSTX-U, consistent with previous DIII-D experimental observations. In contrast, a different behavior has been found for C-Mod and EAST, which operate in the minority heating regime.« less

Characterization and performance of a field aligned ion cyclotron range of frequency antenna in Alcator C-Mod

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

Wukitch, S. J.; Garrett, M. L.; Ochoukov, R.

Ion cyclotron range of frequency (ICRF) heating is expected to provide auxiliary heating for ITER and future fusion reactors where high Z metallic plasma facing components (PFCs) are being considered. Impurity contamination linked to ICRF antenna operation remains a major challenge particularly for devices with high Z metallic PFCs. Here, we report on an experimental investigation to test whether a field aligned (FA) antenna can reduce impurity contamination and impurity sources. We compare the modification of the scrape of layer (SOL) plasma potential of the FA antenna to a conventional, toroidally aligned (TA) antenna, in order to explore the underlyingmore » physics governing impurity contamination linked to ICRF heating. The FA antenna is a 4-strap ICRF antenna where the current straps and antenna enclosure sides are perpendicular to the total magnetic field while the Faraday screen rods are parallel to the total magnetic field. In principle, alignment with respect to the total magnetic field minimizes integrated E|| (electric field along a magnetic field line) via symmetry. A finite element method RF antenna model coupled to a cold plasma model verifies that the integrated E|| should be reduced for all antenna phases. Monopole phasing in particular is expected to have the lowest integrated E||. Consistent with expectations, we observed that the impurity contamination and impurity source at the FA antenna are reduced compared to the TA antenna. In both L and H-mode discharges, the radiated power is 20%–30% lower for a FA-antenna heated discharge than a discharge heated with the TA-antennas. However, inconsistent with expectations, we observe RF induced plasma potentials (via gas-puff imaging and emissive probes to be nearly identical for FA and TA antennas when operated in dipole phasing). Moreover, the highest levels of RF-induced plasma potentials are observed using monopole phasing with the FA antenna. Thus, while impurity contamination and sources are

Characterization of the mutual influence of Ion Cyclotron and Lower Hybrid Range of frequencies systems on EAST

NASA Astrophysics Data System (ADS)

Urbanczyk, Guillaume; Zhang, Xinjun; Qin, Chengming; Zhao, Yanping; Zhang, Tao; Zhang, Ling; Li, Jiangang; Yuan, Shuai; Chen, Liang; Zhang, Heng; Zhang, Jiahui; Wang, Jianhua; Yang, Xiuda; Qian, Jinping

2017-10-01

Waves in the Ion Cyclotron (ICRF) and Lower Hybrid (LH) Range of Frequencies are efficient techniques respectively to heat the plasma and drive current. Main difficulties come from a trade-off between good RF coupling and acceptable level of impurities release. The mutual influence of both systems makes such equilibrium often hard to reach [1]. In order to investigate those interactions based on Scrape-Off Layer (SOL) plasma parameters, a new reciprocating probe was designed allying a three tips Langmuir probe with an emissive wire. The emissive filament provides a precise measure of plasma potential [2], which can be used to calibrate Langmuir probe's results. This paper reports on experimental results obtained on EAST, where there are two ICRF antennas and two LH launchers. Among others diagnostics, the new reciprocating probe enabled to evidence the deleterious influence of ICRF power on LHWs coupling in L-mode plasmas. In areas connected with an active ICRF antenna, SOL potentials increase while densities tend to decrease, respectively enhancing impurities release and deteriorating LHWs coupling. This phenomenon has mostly been attributed to RF sheath; the one that forms on top of Plasma Facing Components (PFCs) and causes ExB density convections [3]. From those experiments it seems ICRF has a strong influence on magnetically connected areas, both in the near field - influencing ICRF waves coupling - and in farther locations such as in front of LH grills. Moreover, influence of ICRF on LH system was observed both in L and H modes. Those results are consistent with RF sheath rectification process. Concerning the influence of LHWs on ICRF coupling, nothing was observed in L-mode. Besides during H-mode experiments, LHWs have been identified as having a mitigating effect on ELMs [4], which on average lowers the pedestal, increasing edge densities to the profit of ICRF waves coupling.

Initial applications of the non-Maxwellian extension of the full-wave TORIC v.5 code in the mid/high harmonic and minority heating regimes

NASA Astrophysics Data System (ADS)

Bertelli, N.; Valeo, E. J.; Phillips, C. K.

2015-11-01

A non Maxwellian extension of the full wave TORIC v.5 code in the mid/high harmonic and minority heating regimes has been revisited. In both regimes the treatment of the non-Maxwellian ions is needed in order to improve the analysis of combined fast wave (FW) and neutral beam injection (NBI) heated discharges in the current fusion devices. Additionally, this extension is also needed in time-dependent analysis where the combined heating experiments are generally considered. Initial numerical cases with thermal ions and with a non-Maxwellian ions are presented for both regimes. The simulations are then compared with results from the AORSA code, which has already been extended to include non-Maxwellian ions. First attempts to apply this extension in a self-consistent way with the NUBEAM module, which is included in the TRANSP code, are also discussed. Work supported by US DOE Contracts # DE-FC02-01ER54648 and DE-AC02-09CH11466.

Evidence of Non-Coincidence between Radio and Optical Positions of ICRF Sources.

NASA Astrophysics Data System (ADS)

Andrei, A. H.; da Silva, D. N.; Assafin, M.; Vieira Martins, R.

2003-11-01

Silva Neto et al. (SNAAVM: 2002) show that comparing the ICRF Ext1 sources standard radio position (Ma et al., 1998) against their optical counterpart position(ZZHJVW: Zacharias et al., 1999; USNO A2.0: Monet et al., 1998), a systematic pattern appears, which depends on the radio structure index (Fey and Charlot, 2000). The optical to radio offsets produce a distribution suggestive of a coincidence of the optical and radio centroids worse for the radio extended than for the radio compact sources. On average, the coincidence between the optical and radio centroids is found 7.9 +/- 1.1 mas smaller for the compact than for the extended sources. Such an effect is reasonably large, and certainly much too large to be due to errors on the VLBI radio position. On the other hand, it is too small to be accounted to the errors on the optical position, which moreover should be independent from the radio structure. Thus, other than a true pattern of centroids non-coincidence, the remaining explanation is of a hazard result. This paper summarizes the several statistical tests used to discard the hazard explanation.

System and method for generating current by selective minority species heating

DOEpatents

Fisch, Nathaniel J.

1983-01-01

A system for the generation of toroidal current in a plasma which is prepared in a toroidal magnetic field. The system utilizes the injection of low-frequency waves into the plasma by means of phased antenna arrays or phased waveguide arrays. The plasma is prepared with a minority ion species of different charge state and different gyrofrequency from the majority ion species. The wave frequency and wave phasing are chosen such that the wave energy is absorbed preferentially by minority species ions traveling in one toroidal direction. The absorption of energy in this manner produces a toroidal electric current even when the injected waves themselves do not have substantial toroidal momentum. This current can be continuously maintained at modest cost in power and may be used to confine the plasma. The system can operate efficiently on fusion grade tokamak plasmas.

Suitability of miniature inductively coupled RF coils as MR-visible markers for clinical purposes.

PubMed

Garnov, Nikita; Thormer, Gregor; Trampel, Robert; Grunder, Wilfried; Kahn, Thomas; Moche, Michael; Busse, Harald

2011-11-01

MR-visible markers have already been used for various purposes such as image registration, motion detection, and device tracking. Inductively coupled RF (ICRF) coils, in particular, provide a high contrast and do not require connecting wires to the scanner, which makes their application highly flexible and safe. This work aims to thoroughly characterize the MR signals of such ICRF markers under various conditions with a special emphasis on fully automatic detection. The small markers consisted of a solenoid coil that was wound around a glass tube containing the MR signal source and tuned to the resonance frequency of a 1.5 T MRI. Marker imaging was performed with a spoiled gradient echo sequence (FLASH) and a balanced steady-state free precession (SSFP) sequence (TrueFISP) in three standard projections. The signal intensities of the markers were recorded for both pulse sequences, three source materials (tap water, distilled water, and contrast agent solution), different flip angles and coil alignments with respect to the B(0) direction as well as for different marker positions in the entire imaging volume (field of view, FOV). Heating of the ICRF coils was measured during 10-min RF expositions to three conventional pulse sequences. Clinical utility of the markers was assessed from their performance in computer-aided detection and in defining double oblique scan planes. For almost the entire FOV (±215 mm) and an estimated 82% of all possible RF coil alignments with respect to B(0), the ICRF markers generated clearly visible MR signals and could be reliably localized over a large range of flip angles, in particular with the TrueFISP sequence (0.3°-4.0°). Generally, TrueFISP provided a higher marker contrast than FLASH. RF exposition caused a moderate heating (≤5 °C) of the ICRF coils only. Small ICRF coils, imaged at low flip angles with a balanced SSFP sequence showed an excellent performance under a variety of experimental conditions and therefore make for a

Recent experimental results of KSTAR RF heating and current drive

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

Wang, S. J., E-mail: sjwang@nfri.re.kr; Kim, J.; Jeong, J. H.

2015-12-10

The overview of KSTAR activities on ICRH, LHCD and ECH/CD including the last experimental results and future plan aiming for long-pulse high-beta plasma will be presented. Recently we achieved reasonable coupling of ICRF power to H-mode plasma through several efforts to increase system reliability. Power balance will be discussed on this experiment. LHCD is still struggling in the low power regime. Review of antenna spectrum for the higher coupling in H-mode plasma will be tried. ECH/CD provides 41 sec, 0.8 MW of heating power to support high-performance long-pulse discharge. Also, 170 GHz ECH system is integrated with the Plasma Control Systemmore » (PCS) for the feedback controlling of NTM. Status and plan of ECH/CD will be discussed. Finally, helicon current drive is being prepared for the next stage of KSTAR operation. The hardware preparation and the calculation results of helicon current drive in KSTAR plasma will be discussed.« less

Recent experimental results of KSTAR RF heating and current drive

NASA Astrophysics Data System (ADS)

Wang, S. J.; Kim, J.; Jeong, J. H.; Kim, H. J.; Joung, M.; Bae, Y. S.; Kwak, J. G.

2015-12-01

The overview of KSTAR activities on ICRH, LHCD and ECH/CD including the last experimental results and future plan aiming for long-pulse high-beta plasma will be presented. Recently we achieved reasonable coupling of ICRF power to H-mode plasma through several efforts to increase system reliability. Power balance will be discussed on this experiment. LHCD is still struggling in the low power regime. Review of antenna spectrum for the higher coupling in H-mode plasma will be tried. ECH/CD provides 41 sec, 0.8 MW of heating power to support high-performance long-pulse discharge. Also, 170 GHz ECH system is integrated with the Plasma Control System (PCS) for the feedback controlling of NTM. Status and plan of ECH/CD will be discussed. Finally, helicon current drive is being prepared for the next stage of KSTAR operation. The hardware preparation and the calculation results of helicon current drive in KSTAR plasma will be discussed.

The role of turbulent suppression in the triggering ITBs on C-Mod

NASA Astrophysics Data System (ADS)

Zhurovich, K.; Fiore, C. L.; Ernst, D. R.; Bonoli, P. T.; Greenwald, M. J.; Hubbard, A. E.; Hughes, J. W.; Marmar, E. S.; Mikkelsen, D. R.; Phillips, P.; Rice, J. E.

2007-11-01

Internal transport barriers can be routinely produced in C-Mod steady EDA H-mode plasmas by applying ICRF at |r/a|>= 0.5. Access to the off-axis ICRF heated ITBs may be understood within the paradigm of marginal stability. Analysis of the Te profiles shows a decrease of R/LTe in the ITB region as the RF resonance is moved off axis. Ti profiles broaden as the ICRF power deposition changes from on-axis to off-axis. TRANSP calculations of the Ti profiles support this trend. Linear GS2 calculations do not reveal any difference in ETG growth rate profiles for ITB vs. non-ITB discharges. However, they do show that the region of stability to ITG modes widens as the ICRF resonance is moved outward. Non-linear simulations show that the outward turbulent particle flux exceeds the Ware pinch by factor of 2 in the outer plasma region. Reducing the temperature gradient significantly decreases the diffusive flux and allows the Ware pinch to peak the density profile. Details of these experiments and simulations will be presented.

The study of heat flux for disruption on experimental advanced superconducting tokamak

NASA Astrophysics Data System (ADS)

Yang, Zhendong; Fang, Jianan; Gong, Xianzu; Gan, Kaifu; Luo, Jiarong; Zhao, Hailin; Cui, Zhixue; Zhang, Bin; Chen, Meiwen

2016-05-01

Disruption of the plasma is one of the most dangerous instabilities in tokamak. During the disruption, most of the plasma thermal energy is lost, which causes damages to the plasma facing components. Infrared (IR) camera is an effective tool to detect the temperature distribution on the first wall, and the energy deposited on the first wall can be calculated from the surface temperature profile measured by the IR camera. This paper concentrates on the characteristics of heat flux distribution onto the first wall under different disruptions, including the minor disruption and the vertical displacement events (VDE) disruption. Several minor disruptions have been observed before the major disruption under the high plasma density in experimental advanced superconducting tokamak. During the minor disruption, the heat fluxes are mainly deposited on the upper/lower divertors. The magnetic configuration prior to the minor disruption is a lower single null with the radial distance between the two separatrices in the outer midplane dRsep = -2 cm, while it changes to upper single null (dRsep = 1.4 cm) during the minor disruption. As for the VDE disruption, the spatial distribution of heat flux exhibits strong toroidal and radial nonuniformity, and the maximum heat flux received on the dome plate can be up to 11 MW/m2.

Influence of Magnetic Field Ripple on the Intrinsic Rotation of Tokamak Plasmas

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

Nave, M. F. F.; Johnson, T.; Eriksson, L.-G.

Using the unique capability of JET to monotonically change the amplitude of the magnetic field ripple, without modifying other relevant equilibrium conditions, the effect of the ripple on the angular rotation frequency of the plasma column was investigated under the conditions of no external momentum input. The ripple amplitude was varied from 0.08% to 1.5% in Ohmic and ion-cyclotron radio-frequency (ICRF) heated plasmas. In both cases the ripple causes counterrotation, indicating a strong torque due to nonambipolar transport of thermal ions and in the case of ICRF also fast ions.

ICRF-edge and surface interactions

NASA Astrophysics Data System (ADS)

D'Ippolito, D. A.; Myra, J. R.

2011-08-01

This paper describes a number of deleterious interactions between radio-frequency (rf) waves and the boundary plasma in fusion experiments. These effects can lead to parasitic power dissipation, reduced heating efficiency, formation of hot spots at material boundaries, sputtering and self-sputtering, and arcing in the antenna structure. Minimizing these interactions is important to the success of rf heating, especially in future experiments with long-pulse or steady-state operation, higher power density, and high-Z divertor and walls. These interactions will be discussed with experimental examples. Finally, the present state of modeling and future plans will be summarized.

A Study of Electron Modes in Off-axis Heated Alcator C-Mod Plasmas

NASA Astrophysics Data System (ADS)

Fiore, C. L.; Ernst, D. R.; Mikkelsen, D.; Ennever, P. C.; Howard, N. T.; Gao, C.; Reinke, M. L.; Rice, J. E.; Hughes, J. W.; Walk, J. R.

2013-10-01

Understanding the underlying physics and stability of the peaked density internal transport barriers (ITB) that have been observed during off-axis ICRF heating of Alcator C-Mod plasmas is the goal of recent gyro-kinetic simulations. Two scenarios are examined: an ITB plasma formed with maximal (4.5 MW) off-axis heating power; also the use of off-axis heating in an I-mode plasma as a target in the hopes of establishing an ITB. In the former, it is expected that evidence of trapped electron mode instabilities could be found if a sufficiently high electron temperature is achieved in the core. Linear simulations show unstable modes are present across the plasma core from r/a = 0.2 and greater. In the latter case, despite establishing similar conditions to those in which ITBS were formed, none developed in the I-mode plasmas. Linear gyrokinetic analyses show no unstable ion modes at r/a < 0.55 in these I-mode plasmas, with both ITG and ETG modes present beyond r/a = 0.65. The details of the experimental results will be presented. Linear and non-linear simulations of both of these cases will attempt to explore the underlying role of electron and ion gradient driven instabilities to explain the observations. This work was supported by US-DoE DE-FC02-99ER54512 and DE-AC02-09CH11466.

Minor actinide transmutation in thorium and uranium matrices in heavy water moderated reactors

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

Bhatti, Zaki; Hyland, B.; Edwards, G.W.R.

2013-07-01

The irradiation of Th{sup 232} breeds fewer of the problematic minor actinides (Np, Am, Cm) than the irradiation of U{sup 238}. This characteristic makes thorium an attractive potential matrix for the transmutation of these minor actinides, as these species can be transmuted without the creation of new actinides as is the case with a uranium fuel matrix. Minor actinides are the main contributors to long term decay heat and radiotoxicity of spent fuel, so reducing their concentration can greatly increase the capacity of a long term deep geological repository. Mixing minor actinides with thorium, three times more common in themore » Earth's crust than natural uranium, has the additional advantage of improving the sustainability of the fuel cycle. In this work, lattice cell calculations have been performed to determine the results of transmuting minor actinides from light water reactor spent fuel in a thorium matrix. 15-year-cooled group-extracted transuranic elements (Np, Pu, Am, Cm) from light water reactor (LWR) spent fuel were used as the fissile component in a thorium-based fuel in a heavy water moderated reactor (HWR). The minor actinide (MA) transmutation rates, spent fuel activity, decay heat and radiotoxicity, are compared with those obtained when the MA were mixed instead with natural uranium and taken to the same burnup. Each bundle contained a central pin containing a burnable neutron absorber whose initial concentration was adjusted to have the same reactivity response (in units of the delayed neutron fraction β) for coolant voiding as standard NU fuel. (authors)« less

A new B-dot probe-based diagnostic for amplitude, polarization, and wavenumber measurements of ion cyclotron range-of frequency fields on ASDEX Upgrade

NASA Astrophysics Data System (ADS)

Ochoukov, R.; Bobkov, V.; Faugel, H.; Fünfgelder, H.; Noterdaeme, J.-M.

2015-11-01

A new B-dot probe-based diagnostic has been installed on an ASDEX Upgrade tokamak to characterize ion cyclotron range-of frequency (ICRF) wave generation and interaction with magnetized plasma. The diagnostic consists of a field-aligned array of B-dot probes, oriented to measure fast and slow ICRF wave fields and their field-aligned wavenumber (k//) spectrum on the low field side of ASDEX Upgrade. A thorough description of the diagnostic and the supporting electronics is provided. In order to compare the measured dominant wavenumber of the local ICRF fields with the expected spectrum of the launched ICRF waves, in-air near-field measurements were performed on the newly installed 3-strap ICRF antenna to reconstruct the dominant launched toroidal wavenumbers (ktor). Measurements during a strap current phasing scan in tokamak discharges reveal an upshift in k// as strap phasing is moved away from the dipole configuration. This result is the opposite of the ktor trend expected from in-air near-field measurements; however, the near-field based reconstruction routine does not account for the effect of induced radiofrequency (RF) currents in the passive antenna structures. The measured exponential increase in the local ICRF wave field amplitude is in agreement with the upshifted k//, as strap phasing moves away from the dipole configuration. An examination of discharges heated with two ICRF antennas simultaneously reveals the existence of beat waves at 1 kHz, as expected from the difference of the two antennas' operating frequencies. Beats are observed on both the fast and the slow wave probes suggesting that the two waves are coupled outside the active antennas. Although the new diagnostic shows consistent trends between the amplitude and the phase measurements in response to changes applied by the ICRF antennas, the disagreement with the in-air near-field measurements remains. An electromagnetic model is currently under development to address this issue.

A new B-dot probe-based diagnostic for amplitude, polarization, and wavenumber measurements of ion cyclotron range-of frequency fields on ASDEX Upgrade.

PubMed

Ochoukov, R; Bobkov, V; Faugel, H; Fünfgelder, H; Noterdaeme, J-M

2015-11-01

A new B-dot probe-based diagnostic has been installed on an ASDEX Upgrade tokamak to characterize ion cyclotron range-of frequency (ICRF) wave generation and interaction with magnetized plasma. The diagnostic consists of a field-aligned array of B-dot probes, oriented to measure fast and slow ICRF wave fields and their field-aligned wavenumber (k(//)) spectrum on the low field side of ASDEX Upgrade. A thorough description of the diagnostic and the supporting electronics is provided. In order to compare the measured dominant wavenumber of the local ICRF fields with the expected spectrum of the launched ICRF waves, in-air near-field measurements were performed on the newly installed 3-strap ICRF antenna to reconstruct the dominant launched toroidal wavenumbers (k(tor)). Measurements during a strap current phasing scan in tokamak discharges reveal an upshift in k(//) as strap phasing is moved away from the dipole configuration. This result is the opposite of the k(tor) trend expected from in-air near-field measurements; however, the near-field based reconstruction routine does not account for the effect of induced radiofrequency (RF) currents in the passive antenna structures. The measured exponential increase in the local ICRF wave field amplitude is in agreement with the upshifted k(//), as strap phasing moves away from the dipole configuration. An examination of discharges heated with two ICRF antennas simultaneously reveals the existence of beat waves at 1 kHz, as expected from the difference of the two antennas' operating frequencies. Beats are observed on both the fast and the slow wave probes suggesting that the two waves are coupled outside the active antennas. Although the new diagnostic shows consistent trends between the amplitude and the phase measurements in response to changes applied by the ICRF antennas, the disagreement with the in-air near-field measurements remains. An electromagnetic model is currently under development to address this issue.

A new B-dot probe-based diagnostic for amplitude, polarization, and wavenumber measurements of ion cyclotron range-of frequency fields on ASDEX Upgrade

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

Ochoukov, R.; Bobkov, V.; Faugel, H.

2015-11-15

A new B-dot probe-based diagnostic has been installed on an ASDEX Upgrade tokamak to characterize ion cyclotron range-of frequency (ICRF) wave generation and interaction with magnetized plasma. The diagnostic consists of a field-aligned array of B-dot probes, oriented to measure fast and slow ICRF wave fields and their field-aligned wavenumber (k{sub //}) spectrum on the low field side of ASDEX Upgrade. A thorough description of the diagnostic and the supporting electronics is provided. In order to compare the measured dominant wavenumber of the local ICRF fields with the expected spectrum of the launched ICRF waves, in-air near-field measurements were performedmore » on the newly installed 3-strap ICRF antenna to reconstruct the dominant launched toroidal wavenumbers (k{sub tor}). Measurements during a strap current phasing scan in tokamak discharges reveal an upshift in k{sub //} as strap phasing is moved away from the dipole configuration. This result is the opposite of the k{sub tor} trend expected from in-air near-field measurements; however, the near-field based reconstruction routine does not account for the effect of induced radiofrequency (RF) currents in the passive antenna structures. The measured exponential increase in the local ICRF wave field amplitude is in agreement with the upshifted k{sub //}, as strap phasing moves away from the dipole configuration. An examination of discharges heated with two ICRF antennas simultaneously reveals the existence of beat waves at 1 kHz, as expected from the difference of the two antennas’ operating frequencies. Beats are observed on both the fast and the slow wave probes suggesting that the two waves are coupled outside the active antennas. Although the new diagnostic shows consistent trends between the amplitude and the phase measurements in response to changes applied by the ICRF antennas, the disagreement with the in-air near-field measurements remains. An electromagnetic model is currently under

The study of heat flux for disruption on experimental advanced superconducting tokamak

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

Yang, Zhendong, E-mail: dongyz@ipp.ac.cn, E-mail: jafang@dhu.edu.cn; Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031; Fang, Jianan, E-mail: dongyz@ipp.ac.cn, E-mail: jafang@dhu.edu.cn

Disruption of the plasma is one of the most dangerous instabilities in tokamak. During the disruption, most of the plasma thermal energy is lost, which causes damages to the plasma facing components. Infrared (IR) camera is an effective tool to detect the temperature distribution on the first wall, and the energy deposited on the first wall can be calculated from the surface temperature profile measured by the IR camera. This paper concentrates on the characteristics of heat flux distribution onto the first wall under different disruptions, including the minor disruption and the vertical displacement events (VDE) disruption. Several minor disruptionsmore » have been observed before the major disruption under the high plasma density in experimental advanced superconducting tokamak. During the minor disruption, the heat fluxes are mainly deposited on the upper/lower divertors. The magnetic configuration prior to the minor disruption is a lower single null with the radial distance between the two separatrices in the outer midplane dR{sub sep} = −2 cm, while it changes to upper single null (dR{sub sep} = 1.4 cm) during the minor disruption. As for the VDE disruption, the spatial distribution of heat flux exhibits strong toroidal and radial nonuniformity, and the maximum heat flux received on the dome plate can be up to 11 MW/m{sup 2}.« less

Electron Profile Stiffness and Critical Gradient Length Studies in the Alcator C-Mod Tokamak

NASA Astrophysics Data System (ADS)

Houshmandyar, Saeid; Hatch, David R.; Liao, Kenneth T.; Zhao, Bingzhe; Phillips, Perry E.; Rowan, William L.; Cao, Norman; Ernst, Darin R.; Rice, John E.

2017-10-01

Electron temperature profile stiffness was investigated at Alcator C-Mod L-mode discharges. Electrons were heated by ion cyclotron range of frequencies (ICRF) through minority heating. The intent of the heating mechanism was to vary the heat flux and simultaneously, gradually change the local gradient. The electron temperature gradient scale length (LTe- 1 = | ∇Te |/Te) was accurately measured through a novel technique, using the high-resolution radiometer ECE diagnostic. The TRANSP power balance analysis (Q/QGB) and the measured scale length (a/LTe) result in critical scale length measurements at all major radius locations. These measurements suggest that the profiles are already at the critical values. Furthermore, the dependence of the stiffness on plasma rotation and magnetic shear will be discussed. In order to understand the underlying mechanism of turbulence for these discharges, simulations using the gyrokinetic code, GENE, were carried out. For linear runs at electron scales, it was found that the largest growth rates are very sensitive to a/LTe variation, which suggests the presence of ETG modes, while the sensitivity studies in the ion scales indicate ITG/TEM modes. Supported by USDoE awards DE-FG03-96ER54373 and DE-FC02-99ER54512.

Production of haemolysins by strains of the Actinobacillus minor/"porcitonsillarum" complex.

PubMed

Arya, Gitanjali; Niven, Donald F

2010-03-24

Actinobacillus minor and "Actinobacillus porcitonsillarum" are distinguished by their haemolytic activities, the latter organism being haemolytic and the former, non-haemolytic. Analysis of a whole genome shotgun sequence, however, revealed that A. minor strain 202, like "A. porcitonsillarum", possesses a haemolysin-encoding apxII operon. The purpose of this study was therefore to investigate haemolysin production by this organism and also by three additional members of the A. minor/"porcitonsillarum" complex, strains 33PN and 7ATS and A. minor strain NM305(T). Primers based on sequences within the apxII genes of strain 202 allowed the amplification of appropriately sized fragments from DNA from strain 33PN suggesting that this organism also possesses an apxII operon. Analysis of a whole genome shotgun sequence failed to reveal any trace of an apxII operon in strain NM305(T) and attempts to amplify apxII genes from DNA from strain 7ATS also failed. Strains 202 and 33PN, and surprisingly, the type strain of A. minor and strain 7ATS, were all found to be haemolysin-positive as growth media from cultures of these organisms could promote the lysis of erythrocytes in suspension. The erythrocyte specificities of the haemolysins produced by strains 202 and 33PN indicated that the haemolytic activities exhibited by these organisms were due to ApxII. In keeping with the apparent lack of apxII genes in strains NM305(T) and 7ATS, the haemolysins produced by these organisms were not erythrocyte-specific and with both organisms, haemolytic activity appeared to be due to a combination of heat-stable and heat-labile components. The identities of these components, however, remain unknown. Copyright 2009 Elsevier B.V. All rights reserved.

Experiments and Simulations of ITER-like Plasmas in Alcator C-Mod

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

.R. Wilson, C.E. Kessel, S. Wolfe, I.H. Hutchinson, P. Bonoli, C. Fiore, A.E. Hubbard, J. Hughes, Y. Lin, Y. Ma, D. Mikkelsen, M. Reinke, S. Scott, A.C.C. Sips, S. Wukitch and the C-Mod Team

Alcator C-Mod is performing ITER-like experiments to benchmark and verify projections to 15 MA ELMy H-mode Inductive ITER discharges. The main focus has been on the transient ramp phases. The plasma current in C-Mod is 1.3 MA and toroidal field is 5.4 T. Both Ohmic and ion cyclotron (ICRF) heated discharges are examined. Plasma current rampup experiments have demonstrated that (ICRF and LH) heating in the rise phase can save voltseconds (V-s), as was predicted for ITER by simulations, but showed that the ICRF had no effect on the current profile versus Ohmic discharges. Rampdown experiments show an overcurrent inmore » the Ohmic coil (OH) at the H to L transition, which can be mitigated by remaining in H-mode into the rampdown. Experiments have shown that when the EDA H-mode is preserved well into the rampdown phase, the density and temperature pedestal heights decrease during the plasma current rampdown. Simulations of the full C-Mod discharges have been done with the Tokamak Simulation Code (TSC) and the Coppi-Tang energy transport model is used with modified settings to provide the best fit to the experimental electron temperature profile. Other transport models have been examined also. __________________________________________________« less

Measurement of the ratio of hydrogen to deuterium at the KSTAR 2009 experimental campaign

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

Kwak, Jong-Gu; Wang, Son Jong; Kim, Sun Ho

The control of the ratio of hydrogen to the deuterium is one of the very important issues for ion cyclotron range of frequency (ICRF) minority heating as well as the plasma wall interaction in the tokamak. The ratio of hydrogen to deuterium during the tokamak shot was deduced from the emission spectroscopy measurements during the KSTAR 2009 experimental campaign. Graphite tiles were used for the plasma facing components (PFCs) at KSTAR and its surface area exposed to the plasma was about 11 m{sup 2}. The data showed that it remained as high as around 50% during the campaign period becausemore » graphite tiles were exposed to the air for about two months and the hydrogen contents at the tiles are not fully pumped out due to the lack of baking on the PFC in the 2009 campaign. The validation of the spectroscopy method was checked by using the Zeeman effects and the ratio of hydrogen to the deuterium is compared with results from the residual gas analysis. During the tokamak shot, the ratio is low below 10% initially and saturated after around 1 s. When there is a hydrogen injection to the vessel via ion cyclotron wall conditioning and the boronization process where the carbone is used, the ratio of the hydrogen to the deuterium is increased by up to 100% and it recovers to around 50% after one day of operation. However it does not decrease below 50% at the end of the experimental campaign. It was found that the full baking on the PFC (with a high temperature and sufficient vacuum pumping) is required for the ratio control which guarantees the efficient ICRF heating at the KSTAR 2010 experimental campaign.« less

Minority Language Rights.

ERIC Educational Resources Information Center

O Riagain, Padraig; Shuibhne, Niamh Nic

1997-01-01

A survey of literature since 1990 on minority languages and language rights focuses on five issues: definition of minorities; individual vs. collective rights; legal bases for minority linguistic rights; applications and interpretations of minority language rights; and assessments of the impact of minority rights legislation. A nine-item annotated…

Multiple Minority Stress and LGBT Community Resilience among Sexual Minority Men.

PubMed

McConnell, Elizabeth A; Janulis, Patrick; Phillips, Gregory; Truong, Roky; Birkett, Michelle

2018-03-01

Minority stress theory has widespread research support in explaining health disparities experienced by sexual and gender minorities. However, less is known about how minority stress impacts multiply marginalized groups, such as lesbian, gay, bisexual, and transgender people of color (LGBT POC). Also, although research has documented resilience in the face of minority stress at the individual level, research is needed that examines macro-level processes such as community resilience (Meyer, 2015). In the current study, we integrate minority stress theory and intersectionality theory to examine multiple minority stress (i.e., racial/ethnic stigma in LGBT spaces and LGBT stigma in one's neighborhood) and community resilience (i.e., connection to LGBT community) among sexual minority men of different racial/ethnic groups who use a geosocial networking application for meeting sexual partners. Results showed that Black sexual minority men reported the highest levels of racial/ethnic stigma in LGBT spaces and White sexual minority men reported the lowest levels, with Asian and Hispanic/Latino men falling in between. Consistent with minority stress theory, racial/ethnic stigma in LGBT spaces and LGBT stigma in one's neighborhood were associated with greater stress for sexual minority men of all racial/ethnic groups. However, connection to LGBT community played more central role in mediating the relationship between stigma and stress for White than POC sexual minority men. Results suggest that minority stress and community resilience processes may differ for White and POC sexual minority men. Potential processes driving these differences and implications for minority stress theory are discussed.

Interaction of minor ions with fast and slow shocks

NASA Technical Reports Server (NTRS)

Whang, Y. C.

1990-01-01

The coronal slow shock was predicted to exist embedded in large coronal holes at 4 to 10 solar radii. A three-fluid model was used to study the jumps in minor ions propertes across the coronal slow shock. The jump conditions were formulated in the de Hoffmann-Teller frame of reference. The Rankine-Hugoniot solution determines the MHD flow and the magnetic field across the shocks. For each minor ion species, the fluid equations for the conservation of mass, momentum, and energy can be solved to determine the velocity and the temperature of the ions across the shock. A simularity solution was also obtained for heavy ions. The results show that on the downstream side of the coronal slow shock the ion temperatures are nearly proportional to the ion masses for He, O, Si, and Fe in agreement with observed ion temperatures in the inner solar wind. This indicates that the possibly existing coronal slow shock can be responsible for the observed heating of minor ions in the solar wind.

Study and design of the ion cyclotron resonance heating system for the stellarator Wendelstein 7-X

NASA Astrophysics Data System (ADS)

Ongena, J.; Messiaen, A.; Van Eester, D.; Schweer, B.; Dumortier, P.; Durodie, F.; Kazakov, Ye. O.; Louche, F.; Vervier, M.; Koch, R.; Krivska, A.; Lyssoivan, A.; Van Schoor, M.; Wauters, T.; Borsuk, V.; Neubauer, O.; Schmitz, O.; Offermans, G.; Altenburg, Y.; Baylard, C.; Birus, D.; Bozhenkov, S.; Hartmann, D. A.; Kallmeyer, J. P.; Renard, S.; Wolf, R. C.; Fülöp, T.

2014-06-01

The current status of the mechanical and electromagnetic design for the ICRF antenna system for W7-X is presented. Two antenna plugins are discussed: one consisting of a pair of straps with pre-matching to cover the first frequency band, 25-38 MHz, and a second one consisting of two short strap triplets to cover a frequency band around 76 MHz. This paper focusses on the two strap antenna for the lower frequency band. Power coupling of the antenna to a reference plasma profile is studied with the help of the codes TOPICA and Microwave Studio that deliver the scattering matrix needed for the optimization of the geometric parameters of the straps and antenna box. Radiation power spectra for different phasings of the two straps are obtained using the code ANTITER II and different heating scenario are discussed. The potential for heating, fast particle generation, and current drive is discussed. The problem of RF coupling through the plasma edge and of edge power deposition is summarized. Important elements of the complete ion cyclotron resonance heating system are discussed: a resonator circuit with tap feed to limit the maximum voltage in the system, and a decoupler to counterbalance the large mutual coupling between the 2 straps. The mechanical design highlights the challenges encountered with this antenna: adaptation to a large variety of plasma configurations, the limited space within the port to accommodate the necessary matching components and the watercooling needed for long pulse operation.

Plasma Heating Simulation in the VASIMR System

NASA Technical Reports Server (NTRS)

Ilin, Andrew V.; ChangDiaz, Franklin R.; Squire, Jared P.; Carter, Mark D.

2005-01-01

The paper describes the recent development in the simulation of the ion-cyclotron acceleration of the plasma in the VASIMR experiment. The modeling is done using an improved EMIR code for RF field calculation together with particle trajectory code for plasma transport calculat ion. The simulation results correlate with experimental data on the p lasma loading and predict higher ICRH performance for a higher density plasma target. These simulations assist in optimizing the ICRF anten na so as to achieve higher VASIMR efficiency.

What is a good death? Minority and non-minority perspectives.

PubMed

Tong, Elizabeth; McGraw, Sarah A; Dobihal, Edward; Baggish, Rosemary; Cherlin, Emily; Bradley, Elizabeth H

2003-01-01

While much attention has been directed at improving the quality of care at the end of life, few studies have examined what determines a good death in different individuals. We sought to identify common domains that characterize a good death in a diverse range of community-dwelling individuals, and to describe differences that might exist between minority and non-minority community-dwelling individuals' views. Using data from 13 focus groups, we identified 10 domains that characterize the quality of the death experience: 1) physical comfort, 2) burdens on family, 3) location and environment, 4) presence of others, 5) concerns regarding prolongation of life, 6) communication, 7) completion and emotional health, 8) spiritual care, 9) cultural concerns, 10) individualization. Differences in minority compared to non-minority views were apparent within the domains of spiritual concerns, cultural concerns, and individualization. The findings may help in efforts to encourage more culturally sensitive and humane end-of-life care for both minority and non-minority individuals.

78 FR 9651 - Approval and Promulgation of Implementation Plans; Oregon: Heat Smart Program and Enforcement...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-11

... Promulgation of Implementation Plans; Oregon: Heat Smart Program and Enforcement Procedures AGENCY... submission contains revisions to the Heat Smart program and to the enforcement procedures and civil penalties... submission contains additional revisions to the Heat Smart program, along with minor revisions and...

On the Hipparcos Link to the ICRF derived from VLA and MERLIN radio astrometry

NASA Astrophysics Data System (ADS)

Hering, R.; Walter, H. G.

2007-06-01

Positions and proper motions obtained from observations by the very large array (VLA) and the multi-element radio-linked interferometer network (MERLIN) are used to establish the link of the Hipparcos Celestial Reference Frame (HCRF) to the International Celestial Reference Frame (ICRF). The VLA and MERLIN data are apparently the latest ones published in the literature. Their mean epoch at around 2001 is about 10 years after the epoch of the Hipparcos catalogue and, therefore, the data are considered suitable to check the Hipparcos link established at epoch 1991.25. The parameters of the link, i.e., the angles of frame orientation and the angular rates of frame rotation, are estimated by fitting these parameters to the differences of the optical and radio positions and proper motions of stars common to the Hipparcos catalogue and the VLA and MERLIN data. Both the estimates of the angles of orientation and the angular rates of rotation show nearly consistent but insignificant results for all samples of stars treated. We conclude that not only the size of the samples of 9 15 stars is too small, but also that the accuracy of the radio positions and, above all, of the radio proper motions is insufficient, the latter being based on early-epoch star positions of low accuracy. The present observational data at epoch 2001 suggest that maintenance of the Hipparcos frame is not feasible at this stage.

Excitation of slow waves in front of an ICRF antenna in a basic plasma experiment

NASA Astrophysics Data System (ADS)

Soni, Kunal; van Compernolle, Bart; Crombe, Kristel; van Eester, Dirk

2017-10-01

Recent results of ICRF experiments at the Large Plasma Device (LAPD) indicate parasitic coupling to the slow wave by the fast wave antenna. Plasma parameters in LAPD are similar to the scrape-off layer of current fusion devices. The machine has a 17 m long, 60 cm diameter magnetized plasma column with typical plasma parameters ne 1012 -1013 cm-3, Te 1 - 10 eV and B0 1000 G. It was found that coupling to the slow mode occurs when the plasma density in front of the antenna is low enough such that the lower hybrid resonance is present in the plasma. The radial density profile is tailored to allow for fast mode propagation in the high density core and slow mode propagation in the low density edge region. Measurements of the wave fields clearly show two distinct modes, one long wavelength m=1 fast wave mode in the core and a short wavelength backward propagating mode in the edge. Perpendicular wave numbers compare favorably to the predicted values. The experiment was done for varying frequencies, ω /Ωi = 25 , 6 and 1.5. Future experiments will investigate the dependence on antenna tilt angle with respect to the magnetic field, with and without Faraday screen. This work is performed at the Basic Plasma Science Facility, sponsored jointly by DOE and NSF.

A developmentally informed adaptation of minority stress for sexual minority adolescents

PubMed Central

Goldbach, Jeremy T.; Gibbs, Jeremy J.

2017-01-01

Sexual minority adolescents (lesbian, gay, bisexual) experience disparities in behavioral health outcomes compared to their heterosexual peers, generally attributed to minority stress. Although evidence of the applicability of the minority stress model among adolescents exists, it is based on a primarily adult literature. Developmental and generational differences demand further examination of minority stress to confirm its applicability. Forty-eight life history interviews with sexual minority adolescents in California (age 14–19; M=19.27 SD = 1.38; 39.6% cismale, 35.4% cisfemale, 25% other gender) were completed, recorded, transcribed, and analyzed using thematic analysis in QSR NVivo. Following a consensus model, all transcripts were double coded. Results suggest that minority stress is appropriate for use with adolescents; however, further emphasis should be placed on social context, coping resources, and developmental processes regarding identity development. A conceptual model is provided, as are implications for research and practice. PMID:28033502

Minority stress is longitudinally associated with alcohol-related problems among sexual minority women.

PubMed

Wilson, Sarah M; Gilmore, Amanda K; Rhew, Isaac C; Hodge, Kimberley A; Kaysen, Debra L

2016-10-01

Compared to sexual minority men and heterosexual women, sexual minority women report elevated alcohol use in young adulthood. Heavy alcohol use and alcohol use disorders disproportionately affect sexual minority women across the lifespan, yet there is limited research investigating reasons for such associations. The present study investigates longitudinal associations between minority stress and both alcohol use as well as self-rated drinking consequences. Participants (N=1057) were self-identified lesbian (40.5%) and bisexual (59.5%) women between the ages of 18 to 25 recruited from across the U.S. using online advertisements. Participants completed four annual surveys. Hurdle mixed effects models were used to assess associations between minority stress and typical weekly drinking and drinking consequences one year later. Minority stress was not significantly associated with subsequent typical drinking. However, minority stress was significantly associated with having any alcohol consequences as well as the count of alcohol consequences one year later after controlling for covariates. Consistent with extant literature, this study provides evidence for a prospective association between minority stress experienced by sexual minority women and drinking consequences. This study also provides support for the potential impact of efforts to reduce minority stress faced by sexual minority women. Published by Elsevier Ltd.

Impact of minor actinide recycling on sustainable fuel cycle options

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

Heidet, F.; Kim, T. K.; Taiwo, T. A.

improve the repository performance. On the other hand, recycling minor actinides also results in an increase of the recycled fuel characteristics and therefore of the charged fuel. The radioactivity is slightly increased while the decay heat and radiotoxicities are very significantly increased. Despite these differences, the characteristics of the fuel at time of discharge remain similar whether minor actinides are recycled or not, with the exception of the inhalation radiotoxicity which is significantly larger with minor actinide recycling. After some cooling the characteristics of the discharged fuel become larger when minor actinides are recycled, potentially affecting the reprocessing plant requirements. Recycling minor actinides has a negative impact on the characteristics of the fresh fuel and will make it more challenging to fabricate fuel containing minor actinides.« less

Experimental Study of RF Sheaths due to Shear Alfv'en Waves in the LAPD

NASA Astrophysics Data System (ADS)

Martin, Michael; van Compernolle, Bart; Carter, Troy; Gekelman, Walter; Pribyl, Patrick; D'Ippolito, Daniel A.; Myra, James R.

2012-10-01

Ion cyclotron resonance frequency (ICRF) heating is an important tool in current fusion experiments and will be an essential part of the heating power in ITER. A current limitation of ICRF heating is impurity generation through the formation of radiofrequency (RF) sheaths, both near-field (at the antenna) and far-field (e.g. in the divertor region). Far-field sheaths are thought to be generated through the direct launch of or mode conversion to shear Alfv'en waves. Shear Alfv'en waves have an electric field component parallel to the background magnetic field near the wall that drives an RF sheath.footnotetextD. A. D'Ippolito and J. R. Myra, Phys. Plasmas 19, 034504 (2012) In this study we directly launch the shear Alfv'en wave and measure the plasma potential oscillations and DC potential in the bulk plasma of the LAPD using emissive and Langmuir probes. Measured changes in the DC plasma potential can serve as an indirect measurement of the formation of an RF sheath because of rectification. These measurements will be useful in guiding future experiments to measure the plasma potential profile inside RF sheaths as part of an ongoing campaign.

Vulnerability to extreme heat and climate change: is ethnicity a factor?

PubMed Central

Hansen, Alana; Bi, Linda; Saniotis, Arthur; Nitschke, Monika

2013-01-01

Background With a warming climate, it is important to identify sub-populations at risk of harm during extreme heat. Several international studies have reported that individuals from ethnic minorities are at increased risk of heat-related illness, for reasons that are not often discussed. Objective The aim of this article is to investigate the underpinning reasons as to why ethnicity may be associated with susceptibility to extreme heat, and how this may be relevant to Australia’s population. Design Drawing upon literary sources, the authors provide commentary on this important, yet poorly understood area of heat research. Results Social and economic disparities, living conditions, language barriers, and occupational exposure are among the many factors contributing to heat-susceptibility among minority ethnic groups in the United States. However, there is a knowledge gap about socio-cultural influences on vulnerability in other countries. Conclusion More research needs to be undertaken to determine the effects of heat on tourists, migrants, and refugees who are confronted with a different climatic environment. Thorough epidemiological investigations of the association between ethnicity and heat-related health outcomes are required, and this could be assisted with better reporting of nationality data in health statistics. Climate change adaptation strategies in Australia and elsewhere need to be ethnically inclusive and cognisant of an upward trend in the proportion of the population who are migrants and refugees. PMID:23899408

Vulnerability to extreme heat and climate change: is ethnicity a factor?

PubMed

Hansen, Alana; Bi, Linda; Saniotis, Arthur; Nitschke, Monika

2013-07-29

With a warming climate, it is important to identify sub-populations at risk of harm during extreme heat. Several international studies have reported that individuals from ethnic minorities are at increased risk of heat-related illness, for reasons that are not often discussed. The aim of this article is to investigate the underpinning reasons as to why ethnicity may be associated with susceptibility to extreme heat, and how this may be relevant to Australia's population. Drawing upon literary sources, the authors provide commentary on this important, yet poorly understood area of heat research. Social and economic disparities, living conditions, language barriers, and occupational exposure are among the many factors contributing to heat-susceptibility among minority ethnic groups in the United States. However, there is a knowledge gap about socio-cultural influences on vulnerability in other countries. More research needs to be undertaken to determine the effects of heat on tourists, migrants, and refugees who are confronted with a different climatic environment. Thorough epidemiological investigations of the association between ethnicity and heat-related health outcomes are required, and this could be assisted with better reporting of nationality data in health statistics. Climate change adaptation strategies in Australia and elsewhere need to be ethnically inclusive and cognisant of an upward trend in the proportion of the population who are migrants and refugees.

Do Double Minority Students Face Double Jeopardy? Testing Minority Stress Theory

ERIC Educational Resources Information Center

Hayes, Jeffrey A.; Chun-Kennedy, Caitlin; Edens, Astrid; Locke, Benjamin D.

2011-01-01

Data from 2 studies revealed that ethnic and sexual minority clients experienced greater psychological distress on multiple dimensions than did European American or heterosexual clients, respectively, as did ethnic and sexual minority students who were not clients. Among sexual minority students, ethnicity was not an added source of distress.…

Vaccines for minor use and minor species (MUMS)--industry's views.

PubMed

Bönisch, B

2004-01-01

Over the past 30 years the importance of vaccines for minor use and minor species has changed for multinational animal health companies. The major reasons for this are being reviewed, with a particular focus on technical, financial and business aspects. Key regulatory obstacles to the development of new products for minor uses and minor species are identified, and examples of vaccines falling into the various categories are provided. A number of proposals are offered with the intention of resolving the medicines availability problem between all the stakeholders involved. Finally, based on the presented scientific and regulatory considerations, ideas are shared as to where the legal and economical framework would need to change to reach a viable solution.

Minority stress, psychosocial resources, and psychological distress among sexual minority breast cancer survivors

PubMed Central

Kamen, Charles; Jabson, Jennifer M.; Mustian, Karen M.; Boehmer, Ulrike

2017-01-01

Objective Few studies have examined unique factors predicting psychological distress among sexual minority (i.e., lesbian and bisexual) women post breast cancer diagnosis. The present study assessed the association of minority stress and psychosocial resource factors with depression and anxiety symptoms among sexual minority breast cancer survivors. Methods 201 sexual minority women who had ductal carcinoma in situ (DCIS) or stage I-IV breast cancer participated in this study through the Love/Avon Army of Women (AOW). Self-report questionnaires were used to assess demographic and clinical factors, minority stress factors (discrimination, minority identity development, outness), psychosocial resources (resilience, social support), and psychological distress (anxiety and depression). These factors were included in a structural equation model, testing psychosocial resources as mediators between minority stress and psychological distress. Results There were no significant differences noted between lesbian and bisexual women. The final structural equation model demonstrated acceptable fit across all sexual minority women, χ2 = 27.83, p > 0.05; confirmatory fit index = 0.97, root-mean-square error of approximation = 0.04, Tucker-Lewis Index = 0.93. The model accounted for significant variance in psychological distress (56%). Examination of indirect effects confirmed that exposure to discrimination was associated with distress via association with resilience. Conclusions Factors unique to sexual minority populations, such as minority stress, may be associated with higher rates of psychological distress among sexual minority breast cancer survivors. However, presence of psychosocial resources may mediate relationships with distress in this population; enhancement of resilience, in particular, could be an aim of psychological intervention. PMID:28165265

Minority stress, psychosocial resources, and psychological distress among sexual minority breast cancer survivors.

PubMed

Kamen, Charles; Jabson, Jennifer M; Mustian, Karen M; Boehmer, Ulrike

2017-06-01

Few studies have examined unique factors predicting psychological distress among sexual minority (i.e., lesbian and bisexual) women postbreast cancer diagnosis. The present study assessed the association of minority stress and psychosocial resource factors with depression and anxiety symptoms among sexual minority breast cancer survivors. Two hundred one sexual minority women who had ductal carcinoma in situ or Stage I-IV breast cancer participated in this study through the Love/Avon Army of Women. Self-report questionnaires were used to assess demographic and clinical factors, minority stress factors (discrimination, minority identity development, outness), psychosocial resources (resilience, social support), and psychological distress (anxiety and depression). These factors were included in a structural equation model, testing psychosocial resources as mediators between minority stress and psychological distress. There were no significant differences noted between lesbian and bisexual women. The final structural equation model demonstrated acceptable fit across all sexual minority women, χ2 = 27.83, p > .05; confirmatory fit index = 0.97, root-mean-square error of approximation = 0.04, Tucker-Lewis index = 0.93. The model accounted for significant variance in psychological distress (56%). Examination of indirect effects confirmed that exposure to discrimination was associated with distress via association with resilience. Factors unique to sexual minority populations, such as minority stress, may be associated with higher rates of psychological distress among sexual minority breast cancer survivors. However, presence of psychosocial resources may mediate relationships with distress in this population; enhancement of resilience, in particular, could be an aim of psychological intervention. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Loosely coupled coaxial TEM applicators for deep-heating.

PubMed

Harrison, W H; Storm, F K

1989-01-01

The development of a coaxial TEM (transverse electromagnetic) deep-heating, non-contacting applicator employing two axially spaced concentric sleeves is described which has electrostatic characteristics and has been named the ESA. Thermal data obtained with the FDA/CDRH elliptic-shaped human torso phantom (with fat overlay) showed nearly uniform heating (+/- 10%) throughout the inner cross-section. Saline tank measurements on a torso cross-section confirmed similar SAR uniformity. Animal experiments with a pig, both with and without blood flow, verified deep-heating and suggested that some preferential central heating occurred. The absence of excessive surface heating indicated that the major portion of the E-field excitation is axially aligned. The non-contacting applicator does not require a water bolus, and experiments showed that moderate patient movement had minor effect on performance.

High field side launch of RF waves: A new approach to reactor actuators

NASA Astrophysics Data System (ADS)

Wallace, G. M.; Baek, S. G.; Bonoli, P. T.; Faust, I. C.; LaBombard, B. L.; Lin, Y.; Mumgaard, R. T.; Parker, R. R.; Shiraiwa, S.; Vieira, R.; Whyte, D. G.; Wukitch, S. J.

2015-12-01

Launching radio frequency (RF) waves from the high field side (HFS) of a tokamak offers significant advantages over low field side (LFS) launch with respect to both wave physics and plasma material interactions (PMI). For lower hybrid (LH) waves, the higher magnetic field opens the window between wave accessibility (n∥≡c k∥/ω >√{1 -ωpi 2/ω2+ωpe 2/ωce 2 }+ωp e/|ωc e| ) and the condition for strong electron Landau damping (n∥˜√{30 /Te } with Te in keV), allowing LH waves from the HFS to penetrate into the core of a burning plasma, while waves launched from the LFS are restricted to the periphery of the plasma. The lower n∥ of waves absorbed at higher Te yields a higher current drive efficiency as well. In the ion cyclotron range of frequencies (ICRF), HFS launch allows for direct access to the mode conversion layer where mode converted waves absorb strongly on thermal electrons and ions, thus avoiding the generation of energetic minority ion tails. The absence of turbulent heat and particle fluxes on the HFS, particularly in double null configuration, makes it the ideal location to minimize PMI damage to the antenna structure. The quiescent SOL also eliminates the need to couple LH waves across a long distance to the separatrix, as the antenna can be located close to plasma without risking damage to the structure. Improved impurity screening on the HFS will help eliminate the long-standing issues of high Z impurity accumulation with ICRF. Looking toward a fusion reactor, the HFS is the only possible location for a plasma-facing RF antenna that will survive long-term. By integrating the antenna into the blanket module it is possible to improve the tritium breeding ratio compared with an antenna occupying an equatorial port plug. Blanket modules will require remote handling of numerous cooling pipes and electrical connections, and the addition of transmission lines will not substantially increase the level of complexity. The obvious engineering

Investigation and optimization of the depth of flue gas heat recovery in surface heat exchangers

NASA Astrophysics Data System (ADS)

Bespalov, V. V.; Bespalov, V. I.; Melnikov, D. V.

2017-09-01

Economic issues associated with designing deep flue gas heat recovery units for natural gas-fired boilers are examined. The governing parameter affecting the performance and cost of surface-type condensing heat recovery heat exchangers is the heat transfer surface area. When firing natural gas, the heat recovery depth depends on the flue gas temperature at the condenser outlet and determines the amount of condensed water vapor. The effect of the outlet flue gas temperature in a heat recovery heat exchanger on the additionally recovered heat power is studied. A correlation has been derived enabling one to determine the best heat recovery depth (or the final cooling temperature) maximizing the anticipated reduced annual profit of a power enterprise from implementation of energy-saving measures. Results of optimization are presented for a surface-type condensing gas-air plate heat recovery heat exchanger for the climatic conditions and the economic situation in Tomsk. The predictions demonstrate that it is economically feasible to design similar heat recovery heat exchangers for a flue gas outlet temperature of 10°C. In this case, the payback period for the investment in the heat recovery heat exchanger will be 1.5 years. The effect of various factors on the optimal outlet flue gas temperature was analyzed. Most climatic, economical, or technological factors have a minor effect on the best outlet temperature, which remains between 5 and 20°C when varying the affecting factors. The derived correlation enables us to preliminary estimate the outlet (final) flue gas temperature that should be used in designing the heat transfer surface of a heat recovery heat exchanger for a gas-fired boiler as applied to the specific climatic conditions.

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

Vdovin V.L.

In this report we describe theory and 3D full wave code description for the wave excitation, propagation and absorption in 3-dimensional (3D) stellarator equilibrium high beta plasma in ion cyclotron frequency range (ICRF). This theory forms a basis for a 3D code creation, urgently needed for the ICRF heating scenarios development for the operated LHD, constructed W7-X, NCSX and projected CSX3 stellarators, as well for re evaluation of ICRF scenarios in operated tokamaks and in the ITER . The theory solves the 3D Maxwell-Vlasov antenna-plasma-conducting shell boundary value problem in the non-orthogonal flux coordinates ({Psi}, {theta}, {var_phi}), {Psi} being magneticmore » flux function, {theta} and {var_phi} being the poloidal and toroidal angles, respectively. All basic physics, like wave refraction, reflection and diffraction are self consistently included, along with the fundamental ion and ion minority cyclotron resonances, two ion hybrid resonance, electron Landau and TTMP absorption. Antenna reactive impedance and loading resistance are also calculated and urgently needed for an antenna -generator matching. This is accomplished in a real confining magnetic field being varying in a plasma major radius direction, in toroidal and poloidal directions, through making use of the hot dense plasma wave induced currents with account to the finite Larmor radius effects. We expand the solution in Fourier series over the toroidal ({var_phi}) and poloidal ({theta}) angles and solve resulting ordinary differential equations in a radial like {Psi}-coordinate by finite difference method. The constructed discretization scheme is divergent-free one, thus retaining the basic properties of original equations. The Fourier expansion over the angle coordinates has given to us the possibility to correctly construct the ''parallel'' wave number k{sub //}, and thereby to correctly describe the ICRF waves absorption by a hot plasma. The toroidal harmonics are tightly coupled with

Minority engineering scholarships, 2012.

DOT National Transportation Integrated Search

2014-02-01

Scholarships for Minority Students Studying Engineering and Science: Support will make scholarships available to minority students : interested in engineering and science and will increase significantly the number of minority students that Missouri S...

Plasma Confinement in the UCLA Electric Tokamak.

NASA Astrophysics Data System (ADS)

Taylor, Robert J.

2001-10-01

The main goal of the newly constructed large Electric Tokamak (R = 5 m, a = 1 m, BT < 0.25 T) is to access an omnigeneous, unity beta(S.C. Cowley, P.K. Kaw, R.S. Kelly, R.M. Kulsrud, Phys. fluids B 3 (1991) 2066.) plasma regime. The design goal was to achieve good confinement at low magnetic fields, consistent with the high beta goal. To keep the program cost down, we adopted the use of ICRF as the primary heating source. Consequently, antenna surfaces covering 1/2 of the surface of the tokamak has been prepared for heating and current drive. Very clean hydrogenic plasmas have been achieved with loop voltage below 0.7 volt and densities 3 times above the Murakami limit, n(0) > 8 x 10^12 cm-3 when there is no MHD activity. The electron temperature, derived from the plasma conductivity is > 250 eV with a central electron energy confinement time > 350 msec in ohmic conditions. The sawteeth period is 50 msec. Edge plasma rotation is induced by plasma biasing via electron injection in an analogous manner to that seen in CCT(R.J. Taylor, M.L. Brown, B.D. Fried, H. Grote, J.R. Liberati, G.J. Morales, P. Pribyl, D. Darrow, and M. Ono. Phys. Rev Lett. 63 2365 1989.) and the neoclassical bifurcation is close to that described by Shaing et al(K.C. Shaing and E.C. Crume, Phys. Rev. Lett. 63 2369 (1989).). In the ohmic phase the confinement tends to be MHD limited. The ICRF heating eliminates the MHD disturbances. Under second harmonic heating conditions, we observe an internal confinement peaking characterized by doubling of the core density and a corresponding increase in the central electron temperature. Charge exchange data, Doppler data in visible H-alpha light, and EC radiation all indicate that ICRF heating works much better than expected. The major effort is focused on increasing the power input and controlling the resulting equilibrium. This task appears to be easy since our current pulses are approaching the 3 second mark without RF heating or current drive. Our

VizieR Online Data Catalog: The orbits of Jupiter's irregular satellites (Brozovic+, 2017)

NASA Astrophysics Data System (ADS)

Brozovic, M.; Jacobson, R. A.

2018-05-01

The large majority of astrometric observations originate from Earth-based telescopes, although there are a handful of observations of Himalia and Callirrhoe from the New Horizons spacecraft flyby of Jupiter. The modern Hipparcos Catalog (Perryman et al. 1997A&A...323L..49P) based astrometry is reported as positions in the ICRF. We convert the older measurements to the ICRF positions. The references to optical observations up to the year 2000 are documented in Jacobson (2000AJ....120.2679J). We continued to use the Jacobson (2000AJ....120.2679J) observational biases for the early measurements. We have since extended the data set with observations published in the Minor Planet Electronic Circulars (MPEC), the International Astronomical Union Circulars (IAUC), the Natural Satellites Data Center (NSDC) database (Arlot & Emelyanov 2009A&A...503..631A), the United States Naval Observatory Flagstaff Station catalog, and the Pulkovo Observatory database. (5 data files).

A theory of heating of quiet solar corona

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

Wu, C. S., E-mail: cszcwu@msn.com; Institute of Space Science, National Central University, Zhongli 32001, Taiwan; Insitute for Physical Sciences and Technology, University of Maryland, College Park, Maryland 20742

A theory is proposed to discuss the creation of hot solar corona. We pay special attention to the transition region and the low corona, and consider that the sun is quiet. The proposed scenario suggests that the protons are heated by intrinsic Alfvénic turbulence, while the ambient electrons are heated by the hot protons via collisions. The theory contains two prime components: the generation of the Alfvénic fluctuations by the heavy minor ions in the transition region and second, the explanation of the temperature profile in the low solar atmosphere. The proposed heating process operates continuously in time and globallymore » in space.« less

The Second Realization of the International Celestial Reference Frame by Very Long Baseline Interferometry

NASA Astrophysics Data System (ADS)

Fey, A. L.; Gordon, D.; Jacobs, C. S.; Ma, C.; Gaume, R. A.; Arias, E. F.; Bianco, G.; Boboltz, D. A.; Böckmann, S.; Bolotin, S.; Charlot, P.; Collioud, A.; Engelhardt, G.; Gipson, J.; Gontier, A.-M.; Heinkelmann, R.; Kurdubov, S.; Lambert, S.; Lytvyn, S.; MacMillan, D. S.; Malkin, Z.; Nothnagel, A.; Ojha, R.; Skurikhina, E.; Sokolova, J.; Souchay, J.; Sovers, O. J.; Tesmer, V.; Titov, O.; Wang, G.; Zharov, V.

2015-08-01

We present the second realization of the International Celestial Reference Frame (ICRF2) at radio wavelengths using nearly 30 years of Very Long Baseline Interferometry observations. ICRF2 contains precise positions of 3414 compact radio astronomical objects and has a positional noise floor of ∼40 μas and a directional stability of the frame axes of ∼10 μas. A set of 295 new “defining” sources was selected on the basis of positional stability and the lack of extensive intrinsic source structure. The positional stability of these 295 defining sources and their more uniform sky distribution eliminates the two greatest weaknesses of the first realization of the International Celestial Reference Frame (ICRF1). Alignment of ICRF2 with the International Celestial Reference System was made using 138 positionally stable sources common to both ICRF2 and ICRF1. The resulting ICRF2 was adopted by the International Astronomical Union as the new fundamental celestial reference frame, replacing ICRF1 as of 2010 January 1.

Radiant heat loss, an unexploited path for heat stress reduction in shaded cattle.

PubMed

Berman, A; Horovitz, T

2012-06-01

Reducing thermal radiation on shaded animals reduces heat stress independently of other means of stress relief. Radiant heat exchange was estimated as a function of climate, shade structure, and animal density. Body surface portion exposed to radiant sources in shaded environments was determined by geometrical relations to determine angles of view of radiation sources (roof underside, sky, sun-exposed ground, shaded ground) on the animal's surface. The relative representation of environment radiation sources on the body surface was determined. Animal thermal radiation balance was derived from radiant heat gained from radiation sources (including surrounding animals) and that lost from the animal surface. The animal environment was assumed to have different shade dimensions and temperatures. These were summed to the radiant heat balance of the cow. The data formed served to estimate the effect of changes in intensity of radiation sources, roof and shaded surface dimensions, and animal density on radiant heat balance (Rbal) of cattle. Roof height effect was expressed by effect of roof temperature on Rbal. Roof underside temperature (35 to 75°C) effect on Rbal was reduced by roof height. If roof height were 4m, an increase in its underside temperature from 35 to 75°C would increase mean Rbal from -63 to -2 W·m⁻², whereas if roof height were 10 m, Rbal would only increase from -99 to -88 W·m⁻². A hot ground temperature increase from 35 to 65°C reduced mean Rbal heat loss from -45 to 3 W·m⁻². Increasing the surface of the shaded area had only a minor effect on Rbal and on the effect of hot ground on Rbal. Increasing shade roof height reduced the effect of roof temperature on Rbal to minor levels when height was > 8m. Increasing the roof height from 4 to 10 m decreased Rbal from -32 to -94 W·m⁻². Increasing indirect radiation from 100 to 500 W·m⁻² was associated with an increase in Rbal from -135 to +23 W·m⁻². Their combined effects were lower

A successful Minority Retention Project.

PubMed

Gardner, Janelle D

2005-12-01

Racial and ethnic minorities are underrepresented in the nursing profession. The high attrition rate of minority students from nursing schools contributes to this problem. Academic leaders are calling for change in nursing education and asking educators to work diligently to retain minority students. This article describes a Minority Retention Project that included interventions designed to enhance the integration of minority students into a supportive learning environment, assist them in using the available resources, and help them feel connected and supported by their peers and faculty. At the end of the first year of the project, the nursing school experienced 100% retention of minority nursing students. Increasing the retention and graduation of minority nursing students supports the continued effort to provide culturally competent health care.

Interaction Between the Celestial and the Terrestrial Reference Frames

NASA Technical Reports Server (NTRS)

Gordon, David; MacMillan, Dan; Bolotin, Sergei; Le Bail, Karine; Gipson, John; Ma, Chopo

2010-01-01

Effects of International Celestial Reference Frame (ICRF2) on the Terrestrial Reference Frames (TRF), CRF and EOP's, The ICRF2 became official on Jan. 1, 2010. It includes positions of 3414 compact radio astronomical sources observed with VLBI, a fivefold increase from the first ICRF. Numerous new VLBI models were used and the most unstable sources were treated as arc parameters to avoid distortions of the frame. The ICRF2 has a noise floor of 40 micro-arc-seconds and an axis stability of 10 micro-arc-seconds. It was aligned with the ICRS using 138 stable sources common to ICRF2 and ICRF-Ext2. Maintenance of ICRF2 is to be made using 295 defining sources chosen for their historical positional stability, minimal source structure, and sky distribution. Their stability and their more uniform sky distribution eliminate the two largest weaknesses of ICRF I. The switchover to ICRF2 has some small effects on the TRF, CRF and Earth Orientation Parameters (EOP). A CRF based on ICRF2 shows a relative rotation of 40 micro-arc-seconds, mostly about the Y-axis. Small shifts are also seen in the EOP's, the largest being 11 micro-arc-seconds in X-pole. Some small but insignificant differences are also seen in the TRF. These results will be presented and discussed.

Recruitment of underrepresented minority students to medical school: minority medical student organizations, an untapped resource.

PubMed

Rumala, Bernice B; Cason, Frederick D

2007-09-01

Recruitment of more underrepresented minority students (black, Hispanic and native American) to increase racial diversity in the physician workforce is on the agenda for medical schools around the nation. The benefits of having a racially diverse class are indisputable. Minority physicians are more likely to provide care to minority, underserved, disadvantaged and low-income populations. Therefore, medical schools would benefit from diversity through utilizing strategies for recruitment of underrepresented minority (URM) students. Numerous recruitment strategies have been employed to increase the number of underrepresented minority students. However, formal collaboration with minority medical student organizations is an underutilized tool in the recruitment process. Many medical schools have informally used minority medical students and members of various minority organizations on campus in the recruitment process, but a formal collaboration which entails a strategic approach on using minority medical student organizations has yet to be included in the literature. This paper discusses the innovative collaboration between the University of Toledo College of Medicine (UTCOM) chapter of the Student National Medical Association (SNMA) and the college of medicine's admissions office to strategize a recruitment plan to increase the number of underrepresented minority students at the UTCOM. This paper suggests that minority medical student organizations, particularly the SNMA, can be used as a recruiting tool; hence, admissions offices cannot negate the usefulness of having formal involvement of minority medical student organizations as a recruiting tool. This approach may also be applicable to residency programs and other graduate professional fields with a severe shortage of URM students.

Minority and minority-deaf professionals. How many and where are they?

PubMed

Andrews, J F; Jordan, D L

1993-12-01

A survey of 6,043 professionals in 349 deaf education programs showed that 10.4% are from nonwhite or minority ethnic/cultural backgrounds. Of these minority professionals, 11.7% are deaf. Only 8 minority deaf administrators were found. Chi-square analyses showed that ethnic/cultural background and hearing loss were strongly associated with the type of program where the professionals were employed. More than half of the minority professionals worked in public schools. The District of Columbia, New York, and Maryland lead the country in the number of deaf professionals employed. More than half of all black deaf professionals work in either D.C. or New York. Texas leads the country in numbers of Hispanic professionals employed, and New Mexico has more Hispanic professionals than does California, New York, or Florida.

The Trojan minor planets

NASA Astrophysics Data System (ADS)

Spratt, Christopher E.

1988-08-01

There are (March, 1988) 3774 minor planets which have received a permanent number. Of these, there are some whose mean distance to the sun is very nearly equal to that of Jupiter, and whose heliocentric longitudes from that planet are about 60°, so that the three bodies concerned (sun, Jupiter, minor planet) make an approximate equilateral triangle. These minor planets, which occur in two distinct groups, one preceding Jupiter and one following, have received the names of the heroes of the Trojan war. This paper concerns the 49 numbered minor planets of this group.

Disproportionate Minority Contact.

PubMed

Fix, Rebecca L; Cyperski, Melissa A; Burkhart, Barry R

2017-04-01

The overrepresentation of racial/ethnic minorities within the criminal justice system relative to their population percentage, a phenomenon termed disproportionate minority contact, has been examined within general adult and adolescent offender populations; yet few studies have tested whether this phenomenon extends to juvenile sexual offenders (JSOs). In addition, few studies have examined whether offender race/ethnicity influences registration and notification requirements, which JSOs are subject to in some U.S. states. The present study assessed for disproportionate minority contact among general delinquent offenders and JSOs, meaning it aimed to test whether the criminal justice system treats those accused of sexual and non-sexual offenses differently by racial/ethnic group. Furthermore, racial/ethnic group differences in risk, legal classification, and sexual offending were examined for JSOs. Results indicated disproportionate minority contact was present among juveniles with non-sexual offenses and JSOs in Alabama. In addition, offense category and risk scores differed between African American and European American JSOs. Finally, registration classifications were predicted by offending characteristics, but not race/ethnicity. Implications and future directions regarding disproportionate minority contact among JSOs and social and legal policy affecting JSOs are discussed.

Minorities and Career Education.

ERIC Educational Resources Information Center

Davenport, Lawrence; Petty, Reginald

This publication explores needed changes in the career preparation and education for minorities and examines the implications of career education emphases for minorities in the U.S. Contents include: (1) "An Overview of Minorities and Career Education" by L. Davenport and R. Petty, (2) "Public Schools, Public Policy, and Public Problems: Some…

22 CFR 51.28 - Minors.

Code of Federal Regulations, 2014 CFR

2014-04-01

... DEPARTMENT OF STATE NATIONALITY AND PASSPORTS PASSPORTS Application § 51.28 Minors. (a) Minors under age 16—(1) Personal appearance. Minors under 16 years of age applying for a passport must appear in person, unless the personal appearance of the minor is specifically excused by a senior passport authorizing...

22 CFR 51.28 - Minors.

Code of Federal Regulations, 2013 CFR

2013-04-01

... DEPARTMENT OF STATE NATIONALITY AND PASSPORTS PASSPORTS Application § 51.28 Minors. (a) Minors under age 16—(1) Personal appearance. Minors under 16 years of age applying for a passport must appear in person, unless the personal appearance of the minor is specifically excused by a senior passport authorizing...

22 CFR 51.28 - Minors.

Code of Federal Regulations, 2011 CFR

2011-04-01

... DEPARTMENT OF STATE NATIONALITY AND PASSPORTS PASSPORTS Application § 51.28 Minors. (a) Minors under age 16—(1) Personal appearance. Minors under 16 years of age applying for a passport must appear in person, unless the personal appearance of the minor is specifically excused by a senior passport authorizing...

22 CFR 51.28 - Minors.

Code of Federal Regulations, 2010 CFR

2010-04-01

... DEPARTMENT OF STATE NATIONALITY AND PASSPORTS PASSPORTS Application § 51.28 Minors. (a) Minors under age 16—(1) Personal appearance. Minors under 16 years of age applying for a passport must appear in person, unless the personal appearance of the minor is specifically excused by a senior passport authorizing...

22 CFR 51.28 - Minors.

Code of Federal Regulations, 2012 CFR

2012-04-01

... DEPARTMENT OF STATE NATIONALITY AND PASSPORTS PASSPORTS Application § 51.28 Minors. (a) Minors under age 16—(1) Personal appearance. Minors under 16 years of age applying for a passport must appear in person, unless the personal appearance of the minor is specifically excused by a senior passport authorizing...

7 CFR 760.114 - Minors.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 7 2011-01-01 2011-01-01 false Minors. 760.114 Section 760.114 Agriculture... Assistance Programs § 760.114 Minors. A minor child is eligible to apply for program benefits under ELAP, LFP, LIP, SURE, or TAP if all the eligibility requirements are met and the provision for minor children in...

7 CFR 760.114 - Minors.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false Minors. 760.114 Section 760.114 Agriculture... Assistance Programs § 760.114 Minors. A minor child is eligible to apply for program benefits under ELAP, LFP, LIP, SURE, or TAP if all the eligibility requirements are met and the provision for minor children in...

Future goal setting, task motivation and learning of minority and non-minority students in Dutch schools.

PubMed

Andriessen, Iris; Phalet, Karen; Lens, Willy

2006-12-01

Cross-cultural research on minority school achievement yields mixed findings on the motivational impact of future goal setting for students from disadvantaged minority groups. Relevant and recent motivational research, integrating Future Time Perspective Theory with Self-Determination Theory, has not yet been validated among minority students. To replicate across cultures the known motivational benefits of perceived instrumentality and internal regulation by distant future goals; to clarify when and how the future motivates minority students' educational performance. Participants in this study were 279 minority students (100 of Turkish and 179 of Moroccan origin) and 229 native Dutch students in Dutch secondary schools. Participants rated the importance of future goals, their perceptions of instrumentality, their task motivation and learning strategies. Dependent measures and their functional relations with future goal setting were simultaneously validated across minority and non-minority students, using structural equation modelling in multiple groups. As expected, Positive Perceived Instrumentality for the future increases task motivation and (indirectly) adaptive learning of both minority and non-minority students. But especially internally regulating future goals are strongly related to more task motivation and indirectly to more adaptive learning strategies. Our findings throw new light on the role of future goal setting in minority school careers: distant future goals enhance minority and non-minority students' motivation and learning, if students perceive positive instrumentality and if their schoolwork is internally regulated by future goals.

Eddy Covariance Measurements Over a Maize Field: The Contribution of Minor Flux Terms to the Energy Balance Gap

NASA Astrophysics Data System (ADS)

Smidt, J.; Ingwersen, J.; Streck, T.

2015-12-01

The lack of energy balance closure is a long-standing problem in eddy covariance (EC) measurements. The energy balance equation is defined as Rn - G = H + λE, where Rn is net radiation, G is the ground heat flux, H is the sensible heat flux and λE is the latent heat flux. In most cases of energy imbalance, either Rn is overestimated or the ground heat and turbulent fluxes are underestimated. Multiple studies have shown that calculations, incorrect instrument installation/calibration and measurement errors alone do not entirely account for this imbalance. Rather, research is now focused on previously neglected sources of heat storage in the soil, biomass and air beneath the EC station. This project examined the potential of five "minor flux terms" - soil heat storage, biomass heat storage, energy consumption by photosynthesis, air heat storage and atmospheric moisture change, to further close the energy balance gap. Eddy covariance measurements were conducted at a maize (Zea mays) field in southwest Germany during summer 2014. Soil heat storage was measured for six weeks at 11 sites around the field footprint. Biomass and air heat storage were measured for six subsequent weeks at seven sites around the field footprint. Energy consumption by photosynthesis was calculated using the CO2 flux data. Evapotranspiration was calculated using the water balance method and then compared to the flux data processed with three post-closure methods: the sensible heat flux, the latent heat flux and the Bowen ratio post-closure methods. An energy balance closure of 66% was achieved by the EC station measurements over the entire investigation period. During the soil heat flux campaign, EC station closure was 74.1%, and the field footprint soil heat storage contributed 3.3% additional closure. During the second minor flux term measurement period, closure with the EC station data was 91%. Biomass heat storage resulted in 1.1% additional closure, the photosynthesis flux closed the gap

Sexual Minority Stressors, Internalizing Symptoms, and Unhealthy Eating Behaviors in Sexual Minority Youth

PubMed Central

Katz-Wise, Sabra L.; Calzo, Jerel P.; Scherer, Emily A.; Sarda, Vishnudas; Jackson, Benita; Haines, Jess; Austin, S. Bryn

2015-01-01

Background Sexual minorities are more likely than heterosexuals to engage in unhealthy eating behaviors. Purpose To examine sexual minority stressors and internalizing symptoms as predictors of unhealthy eating behaviors among sexual minority youth. Methods We used longitudinal data from 1461 sexual minority youth in the Growing Up Today Study, across ages 14-28 years. We hypothesized that sexual minority stressors would predict unhealthy eating behaviors, in part due to internalizing symptoms. Linear regression models fit via generalized estimating equations were stratified by gender and sexual orientation. Results Significant positive and inverse associations between stressors and eating behaviors were detected among females and males, with more significant associations among females. Associations were attenuated by up to 71% for females and 12% for males when internalizing symptoms were added to the models. Conclusions Sexual minority stressors predicted unhealthy eating behaviors overall and more so for some sexual orientation and gender groups; associations were partially explained by internalizing symptoms. The conceptual model appears to best describe the experiences of bisexual females. Findings have clinical implications for adolescent health. PMID:26156678

Testing a Model of Minority Identity Achievement, Identity Affirmation and Psychological Well-Being among Ethnic Minority and Sexual Minority Individuals

PubMed Central

2011-01-01

How is social identity related to psychological well-being among minority individuals? Drawing on developmental models of identity formation (e.g., Erikson, 1968) and on Social Identity Theory (Tajfel & Turner, 1979), we tested a conceptual model examining links between two key aspects of social identity and psychological well-being. We proposed that the association between identity achievement (exploring and understanding the meaning of one’s identity) and psychological well-being is mediated by identity affirmation (developing positive feelings and a sense of belonging to one’s social group). Across three studies, including ethnic minority high school students (Study 1), ethnic minority college students (Study 2) and lesbian and gay male adults (Study 3), we found strong support for the model. Results suggest that the process of exploring and understanding one’s minority identity can serve as an important basis for developing positive feelings toward and an enhanced sense of attachment to the group which can in turn confer psychological benefits for minority individuals. Implications and directions for future research are discussed. PMID:21341900

Minority workers or minority human beings? A European dilemma

NASA Astrophysics Data System (ADS)

Skutnabb-Kangas, Tove; Phillipson, Robert

1996-07-01

"European" identities may be politonymic, toponymic, ethnomyic or linguonymic (Bromley 1984). Each dimension may affect whether migrant minorities are treated as "European", and influence their schooling, integration and rights. Treatment and terminology vary in different states and periods of migration. However, the position for immigrated minorities is that they are still largely seen as workers rather than human beings with equal rights. Lack of success in schools is blamed on the migrants themselves rather than the educational system. This construction of migrants as being deficient is parallel to educational practice which falls within a UN definition of linguistic genocide, and contributes to mis-education. If current efforts in international bodies to codify educational linguistic human rights were to lead to greater support for minorities, this could assist in a redefinition of national identities and a reduction of racism and conflict.

Minority Record Reported

ERIC Educational Resources Information Center

Hobbs, Louise; Pakiser, L. C.

1978-01-01

Forty-two minority students receiving American Geological Institute (AGI) scholarships are discussed in this article. The value of the AGI scholarship program is examined with regard to student academic success, future professional success, and minority representation. Most faculty members and employers involved in the program were favorably…

Minorities and Malnutrition.

ERIC Educational Resources Information Center

Kornegay, Francis A.

Various aspects of the relationship between minorities and malnutrition are discussed in this brief paper. Malnutrition, one of the byproducts of low economic status, is creating a crisis-proportion health problem affecting minority citizens. Malnutrition seriously affects children, older people in poverty, and chronically unemployed or…

Minority engineering scholarships renewal, 2011.

DOT National Transportation Integrated Search

2012-08-01

Scholarships for Minority Students Studying Engineering and Science : Support will make scholarships available to minority students : interested in engineering and science and will increase significantly the number of minority students that Missouri ...

Crustal heat production and estimate of terrestrial heat flow in central East Antarctica, with implications for thermal input to the East Antarctic ice sheet

NASA Astrophysics Data System (ADS)

Goodge, John W.

2018-02-01

East Antarctica resembles that in the Proterozoic Arunta and Tennant Creek inliers of Australia but is dissimilar to other areas like the Central Australian Heat Flow Province that are characterized by anomalously high heat flow. Age variation within the sample suite indicates that central East Antarctic lithosphere is heterogeneous, yet the average heat production and heat flow of four age subgroups cluster around the group mean, indicating minor variation in the thermal contribution to the overlying ice sheet from upper crustal heat production. Despite these minor differences, ice-sheet models may favor a geologically realistic input of crustal heat flow represented by the distribution of ages and geothermal characteristics found in these glacial clasts.

Heat illnesses: a hot topic in the setting of global climate change.

PubMed

Sankoff, Jeffrey

2015-01-01

Heat illnesses affect a large number of people every year and are becoming an increasing cause of pathology as climate change results in increasing global temperatures. This article will review the physiological responses to heat, as well as the pathophysiological processes that result in heat illnesses. The emphasis will be on providing general practitioners (GPs) with an understanding of how to prevent heat illness in their patients and how to predict who is most at risk. Heat illnesses may be thought of as minor or major illnesses, any of which may present to the GP. Consideration must be given to identifying those who need more critical intervention and on when to transfer for higher-level of care.

40 CFR 161.60 - Minor uses.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Minor uses. 161.60 Section 161.60... FOR REGISTRATION OF ANTIMICROBIAL PESTICIDES General Provisions § 161.60 Minor uses. (a) Minor use policy. A minor use of a pesticide is a use on a “minor crop” (a crop which is planted on a small total...

[Medical confidentiality for minors].

PubMed

Peyrebrune, Cécile; Génot-Pok, Isabelle

2009-12-20

The new statutory provisions on the care of minors have given a legal framework for primary healthcare professionals. They clarify the rights of minors and their general application to improve the quality of the healthcare system. They are valuable and relevant tools for general practitioners in their day to day practice, and they help improve the medical care of minors, currently considered as a real public health problem.

Minority Stress and Psychological Distress among Asian American Sexual Minority Persons

ERIC Educational Resources Information Center

Szymanski, Dawn M.; Sung, Mi Ra

2010-01-01

The purpose of this study was to examine multiple minority stressors (i.e., heterosexist events, racist events, heterosexism in communities of color, racism in sexual minority communities, race-related dating and relationship problems, internalized heterosexism or homophobia, outness to family, and outness to world) as they relate to the…

Exploring Discrimination and Mental Health Disparities Faced By Black Sexual Minority Women Using a Minority Stress Framework.

PubMed

Calabrese, Sarah K; Meyer, Ilan H; Overstreet, Nicole M; Haile, Rahwa; Hansen, Nathan B

2015-09-01

Black sexual minority women are triply marginalized due to their race, gender, and sexual orientation. We compared three dimensions of discrimination-frequency (regularity of occurrences), scope (number of types of discriminatory acts experienced), and number of bases (number of social statuses to which discrimination was attributed)-and self-reported mental health (depressive symptoms, psychological well-being, and social well-being) between 64 Black sexual minority women and each of two groups sharing two of three marginalized statuses: (a) 67 White sexual minority women and (b) 67 Black sexual minority men. Black sexual minority women reported greater discrimination frequency, scope, and number of bases and poorer psychological and social well-being than White sexual minority women and more discrimination bases, a higher level of depressive symptoms, and poorer social well-being than Black sexual minority men. We then tested and contrasted dimensions of discrimination as mediators between social status (race or gender) and mental health outcomes. Discrimination frequency and scope mediated the association between race and mental health, with a stronger effect via frequency among sexual minority women. Number of discrimination bases mediated the association between gender and mental health among Black sexual minorities. Future research and clinical practice would benefit from considering Black sexual minority women's mental health in a multidimensional minority stress context.

Sexual minority-related victimization as a mediator of mental health disparities in sexual minority youth: a longitudinal analysis.

PubMed

Burton, Chad M; Marshal, Michael P; Chisolm, Deena J; Sucato, Gina S; Friedman, Mark S

2013-03-01

Sexual minority youth (youth who are attracted to the same sex or endorse a gay/lesbian/bisexual identity) report significantly higher rates of depression and suicidality than heterosexual youth. The minority stress hypothesis contends that the stigma and discrimination experienced by sexual minority youth create a hostile social environment that can lead to chronic stress and mental health problems. The present study used longitudinal mediation models to directly test sexual minority-specific victimization as a potential explanatory mechanism of the mental health disparities of sexual minority youth. One hundred ninety-seven adolescents (14-19 years old; 70 % female; 29 % sexual minority) completed measures of sexual minority-specific victimization, depressive symptoms, and suicidality at two time points 6 months apart. Compared to heterosexual youth, sexual minority youth reported higher levels of sexual minority-specific victimization, depressive symptoms, and suicidality. Sexual minority-specific victimization significantly mediated the effect of sexual minority status on depressive symptoms and suicidality. The results support the minority stress hypothesis that targeted harassment and victimization are partly responsible for the higher levels of depressive symptoms and suicidality found in sexual minority youth. This research lends support to public policy initiatives that reduce bullying and hate crimes because reducing victimization can have a significant impact on the health and well-being of sexual minority youth.

Sexual Minority-Related Victimization as a Mediator of Mental Health Disparities in Sexual Minority Youth: A Longitudinal Analysis

PubMed Central

Burton, Chad M.; Marshal, Michael P.; Chisolm, Deena J.; Sucato, Gina S.; Friedman, Mark S.

2013-01-01

Sexual minority youth (youth who are attracted to the same sex or endorse a gay/lesbian/bisexual identity) report significantly higher rates of depression and suicidality than heterosexual youth. The minority stress hypothesis contends that the stigma and discrimination experienced by sexual minority youth create a hostile social environment that can lead to chronic stress and mental health problems. The present study used longitudinal mediation models to directly test sexual minority-specific victimization as a potential explanatory mechanism of the mental health disparities of sexual minority youth. One hundred ninety seven adolescents (14–19 years old; 70% female; 29% sexual minority) completed measures of sexual minority-specific victimization, depressive symptoms, and suicidality at two time points six months apart. Compared to heterosexual youth, sexual minority youth reported higher levels of sexual minority-specific victimization, depressive symptoms, and suicidality. Sexual minority-specific victimization significantly mediated the effect of sexual minority status on depressive symptoms and suicidality. The results support the minority stress hypothesis that targeted harassment and victimization are partly responsible for the higher levels of depressive symptoms and suicidality found in sexual minority youth. This research lends support to public policy initiatives that reduce bullying and hate crimes because reducing victimization can have a significant impact on the health and well-being of sexual minority youth. PMID:23292751

76 FR 11331 - New Animal Drugs for Minor Use and Minor Species; Confirmation of Effective Date

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-02

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration 21 CFR Part 516 [Docket No. FDA-2010-N-0534] RIN 0910-AG58 New Animal Drugs for Minor Use and Minor Species; Confirmation of... direct final rule amends the regulations regarding new animal drugs for minor use and minor species (MUMS...

Socioeconomic status and parenting in ethnic minority families: testing a minority family stress model.

PubMed

Emmen, Rosanneke A G; Malda, Maike; Mesman, Judi; van Ijzendoorn, Marinus H; Prevoo, Mariëlle J L; Yeniad, Nihal

2013-12-01

According to the family stress model (Conger & Donnellan, 2007), low socioeconomic status (SES) predicts less-than-optimal parenting through family stress. Minority families generally come from lower SES backgrounds than majority families, and may experience additional stressors associated with their minority status, such as acculturation stress. The primary goal of this study was to test a minority family stress model with a general family stress pathway, as well as a pathway specific to ethnic minority families. The sample consisted of 107 Turkish-Dutch mothers and their 5- to 6-year-old children, and positive parenting was observed during a 7-min problem-solving task. In addition, mothers reported their daily hassles, psychological distress, and acculturation stress. The relation between SES and positive parenting was partially mediated by both general maternal psychological stress and maternal acculturation stress. Our study contributes to the argument that stressors specific to minority status should be considered in addition to more general demographic and family stressors in understanding parenting behavior in ethnic minority families.

The Role of Plasma Rotation in C-Mod Internal Transport Barriers

NASA Astrophysics Data System (ADS)

Fiore, C. L.; Ernst, D. R.; Rice, J. E.; Podpaly, Y.; Reinke, M. L.; Greenwald, M. J.; Hughes, J. W.; Ma, Y.; Bespamyatnov, I. O.; Rowan, W. L.

2010-11-01

ITBs in Alcator C-Mod featuring highly peaked density and pressure profiles are induced by injecting ICRF power with the second harmonic of the resonant frequency for minority hydrogen off-axis at the plasma half radius. These ITBs are formed in the absence of particle or momentum injection, and with monotonic q profiles with qmin < 1. In C-Mod a strong co-current toroidal rotation, peaked on axis, develops after the transition to H-mode. If an ITB forms, this rotation decreases in the center of the plasma and forms a well, and often reverses direction in the core. This indicates that there is a strong EXB shearing rate in the region where the foot in the ITB density profile is observed. Preliminary gyrokinetic analyses indicate that this shearing rate is comparable to the ion temperature gradient mode (ITG) growth rate at this location and may be responsible for stabilizing the turbulence. Gyrokinetic analyses of recent experimental data obtained from a complete scan of the ICRF resonance position across the entire C-Mod plasma will be presented.

Exploring Discrimination and Mental Health Disparities Faced By Black Sexual Minority Women Using a Minority Stress Framework

PubMed Central

Calabrese, Sarah K.; Meyer, Ilan H.; Overstreet, Nicole M.; Haile, Rahwa; Hansen, Nathan B.

2015-01-01

Black sexual minority women are triply marginalized due to their race, gender, and sexual orientation. We compared three dimensions of discrimination—frequency (regularity of occurrences), scope (number of types of discriminatory acts experienced), and number of bases (number of social statuses to which discrimination was attributed)—and self-reported mental health (depressive symptoms, psychological well-being, and social well-being) between 64 Black sexual minority women and each of two groups sharing two of three marginalized statuses: (a) 67 White sexual minority women and (b) 67 Black sexual minority men. Black sexual minority women reported greater discrimination frequency, scope, and number of bases and poorer psychological and social well-being than White sexual minority women and more discrimination bases, a higher level of depressive symptoms, and poorer social well-being than Black sexual minority men. We then tested and contrasted dimensions of discrimination as mediators between social status (race or gender) and mental health outcomes. Discrimination frequency and scope mediated the association between race and mental health, with a stronger effect via frequency among sexual minority women. Number of discrimination bases mediated the association between gender and mental health among Black sexual minorities. Future research and clinical practice would benefit from considering Black sexual minority women's mental health in a multidimensional minority stress context. PMID:26424904

Development of long-pulse heating & current drive actuators & operational techniques compatible with a high-Z divertor & first wall

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

Tynan, George

This was a collaboration between UCSD and MIT to study the effective application of ion-cyclotron heating (ICRH) on the EAST tokamak, located in China. The original goal was for UCSD to develop a diagnostic that would allow measurement of the steady state, or DC, convection pattern that develops on magnetic field lines that attach or connect to the ICRH antenna. This diagnostic would then be used to develop techniques and approaches that minimize or even eliminate such DC convection during application of strong ICRH heating. This was thought to then indicate reduction or elimination of parasitic losses of heating power,more » and thus be an indicator of effective RF heating. The original plan to use high speed digital gas-puff imaging (GPI) of the antenna-edge plasma region in EAST was ultimately unsuccessful due to limitations in machine and camera operations. We then decided to attempt the same experiment on the ALCATOR C-MOD tokamak at MIT which had a similar instrument already installed. This effort was ultimately successful, and demonstrated that the underlying idea of using GPI as a diagnostic for ICRH antenna physics would, in fact, work. The two-dimensional velocity fields of the turbulent structures, which are advected by RF-induced E x B flows, are obtained via the time-delay estimation (TDE) techniques. Both the magnitude and radial extension of the radial electric field E-r were observed to increase with the toroidal magnetic field strength B and the ICRF power. The TDE estimations of RF-induced plasma potentials are consistent with previous results based on the probe measurements of poloidal phase velocity. The results suggest that effective ICRH heating with reduced impurity production is possible when the antenna/box system is designed so as to reduce the RF-induced image currents that flow in the grounded conducting antenna frame elements that surround the RF antenna current straps.« less

MINORITY STRESS, POSITIVE IDENTITY DEVELOPMENT, AND DEPRESSIVE SYMPTOMS: IMPLICATIONS FOR RESILIENCE AMONG SEXUAL MINORITY MALE YOUTH.

PubMed

Bruce, Douglas; Harper, Gary W; Bauermeister, Jose A

2015-09-01

Minority stress processes have been shown to have significant associations with negative mental health outcomes among sexual minority populations. Given that adversity may be experienced growing up as a sexual minority in heteronormative, if not heterosexist, environments, our research on resilience among sexual minority male youth proposes that positive identity development may buffer the effects of a range of minority stress processes. An ethnically diverse sample of 200 sexual minority males ages 16-24 (mean age, 20.9 years) was recruited using mixed recruitment methods. We developed and tested two new measures: concealment stress during adolescence and sexual minority-related positive identity development. We then tested a path model that assessed the effects of minority stressors, positive identity development, and social support on major depressive symptoms. Experience of stigma was associated with internalized homophobia (β=.138, p<.05) and major depressive symptoms (β=1.076, OR=2.933, p<.001), and internalized homophobia partially mediated experience's effects on major depression (β=.773, OR=2.167, p<.001). Concealment stress was associated with positive identity development (β=.155, p<.05) and internalized homophobia (β=.418, p<.001), and positive identity development partially mediated concealment stress's effects on internalized homophobia (β=-.527, p<.001). Concealment stress demonstrated a direct effect on major depression (β=1.400, OR=4.056, p<.001), and indirect paths to social support through positive identity development. With these results, we offer an exploratory model that empirically identifies significant paths among minority stress dimensions, positive identity development, and major depressive symptoms. This study helps further our understanding of minority stress, identity development, and resources of resilience among sexual minority male youth.

The Impact of Minority Stress on Mental Health and Substance Use Among Sexual Minority Women

PubMed Central

Lehavot, Keren; Simoni, Jane M.

2014-01-01

Objective We examined the direct and indirect impact of minority stress on mental health and substance use among sexual minority women. Method A combination of snowball and targeted sampling strategies was used to recruit lesbian and bisexual women (N = 1,381) for a cross-sectional, online survey. Participants (M age = 33.54 years; 74% White) completed a questionnaire assessing gender expression, minority stressors (i.e., victimization, internalized homophobia, and concealment), social–psychological resources (i.e., social support, spirituality), and health-related outcomes. We used structural equation modeling to test associations among these factors, with gender expression as an antecedent and social–psychological resources as a mediator between minority stress and health. Results The final model demonstrated acceptable fit, χ2(79) = 414.00, p < .05, confirmatory fit index = .93, Tucker–Lewis index = .91, standardized root-mean-square residual = .05, root-mean-square error of approximation = .06, accounting for significant portions of the variance in mental health problems (56%) and substance use (14%), as well as the mediator social–psychological resources (24%). Beyond indirect effects of minority stress on health outcomes, direct links emerged between victimization and substance use and between internalized homophobia and substance use. Conclusions Findings indicate a significant impact of minority stressors and social–psychological resources on mental health and substance use among sexual minority women. The results improve understanding of the distinct role of various minority stressors and their mechanisms on health outcomes. Health care professionals should assess for minority stress and coping resources and refer for evidence-based psychosocial treatments. PMID:21341888

The impact of minority stress on mental health and substance use among sexual minority women.

PubMed

Lehavot, Keren; Simoni, Jane M

2011-04-01

We examined the direct and indirect impact of minority stress on mental health and substance use among sexual minority women. A combination of snowball and targeted sampling strategies was used to recruit lesbian and bisexual women (N = 1,381) for a cross-sectional, online survey. Participants (M age = 33.54 years; 74% White) completed a questionnaire assessing gender expression, minority stressors (i.e., victimization, internalized homophobia, and concealment), social-psychological resources (i.e., social support, spirituality), and health-related outcomes. We used structural equation modeling to test associations among these factors, with gender expression as an antecedent and social-psychological resources as a mediator between minority stress and health. The final model demonstrated acceptable fit, χ²(79) = 414.00, p < .05, confirmatory fit index = .93, Tucker-Lewis index = .91, standardized root-mean-square residual = .05, root-mean-square error of approximation = .06, accounting for significant portions of the variance in mental health problems (56%) and substance use (14%), as well as the mediator social-psychological resources (24%). Beyond indirect effects of minority stress on health outcomes, direct links emerged between victimization and substance use and between internalized homophobia and substance use. Findings indicate a significant impact of minority stressors and social-psychological resources on mental health and substance use among sexual minority women. The results improve understanding of the distinct role of various minority stressors and their mechanisms on health outcomes. Health care professionals should assess for minority stress and coping resources and refer for evidence-based psychosocial treatments. (c) 2011 APA, all rights reserved.

The Economics of Minorities

ERIC Educational Resources Information Center

Coles, Flournoy A., Jr.

1973-01-01

This article discusses some of the more important economic problems of minorities in the United States, identifying the economics of minorities with the economics of poverty, discrimination, exploitation, urban life, and alienation. (JM)

Penetrators for delivering Scientific equipment to minor bodies by flying-pass missions.

NASA Astrophysics Data System (ADS)

Bagrov, Alexander; Martynov, Maxim; Pichkhadze, Konstantin M.; Dolgopolov, Vladimir; Sysoev, Valentin

Many space missions are planned to have close encounters with Solar system minor bodies as a pass-fly. Short time of such close encounters were effectively used for photographing of these bodies, i.e. for distant investigations only because of large velocities of the encounter. We propose to use high-velocity penetrators to provide contact investigations of the minor bodies in situ. These devices were designed by Lavochkin Association for lunar missions. They were designed for long lived scientific equipment to be placed under surface up to depth 2...3 m. Penetrators could survive under 500 g shock, so the contact velocity was from 90 to 250 m/s, so each of them had booster engine to decelerate orbital velocity. As flying-pass velocity near minor body can be more then 10 km/s, penetrators would hit target at speed above 1 km/s and successfully bear 1500 g. To do so we propose to fulfill whole internal space inside penetrator with distilled water and froze it to temperature - 80°C or lower. At this temperature water ice is as hard as steel, so penetrator will plunge into target like armour-piercing shell. After landing protective ice will be evaporated (particularly due to heating from collision) and all sensitive mechanics will be set free.

Alleviation of cadmium toxicity in Lemna minor by exogenous salicylic acid.

PubMed

Lu, Qianqian; Zhang, Tingting; Zhang, Wei; Su, Chunlei; Yang, Yaru; Hu, Dan; Xu, Qinsong

2018-01-01

Cadmium (Cd) is a significant environmental pollutant in the aquatic environment. Salicylic acid (SA) is a ubiquitous phenolic compound. The goal of this study was to assess the morphological, physiological and biochemical changes in duckweed (L. minor) upon exposure to 10μM CdCl 2 , 10μM CdCl 2 plus 50μM SA, or 50μM SA for 7 days. Reversing the effects of Cd, SA decreased Cd accumulation in plants, improved accumulation of minerals (Ca, Mg, Fe, B, Mo) absorption, increased endogenous SA concentration, and phenylalanine ammonialyase (PAL) activity. Chlorosis-associated symptoms, the reduction in chlorophyll content, and the overproduction of reactive oxygen species induced by Cd exposure were largely reversed by SA. SA significantly decreased the toxic effects of Cd on the activities of the superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, and glutathione reductase in the fronds of L. minor. Furthermore, SA reversed the detrimental effects of Cd on total ascorbate, glutathione, the ascorbic acid/oxidized dehydroascorbate and glutathione/glutathione disulphide ratios, lipid peroxidation, malondialdehyde concentration, lipoxygenase activity, and the accumulation of proline. SA induced the up-regulation of heat shock proteins (Hsp70) and attenuated the adverse effects of Cd on cell viability. These results suggest that SA confers tolerance to Cd stress in L. minor through different mechanisms. Copyright © 2017 Elsevier Inc. All rights reserved.

Counseling Minors: Ethical and Legal Issues.

ERIC Educational Resources Information Center

Ledyard, Pat

1998-01-01

Discusses the ethical and legal dilemmas facing counselors who work with minors in the school system. From an ethical perspective, minors should be able to expect confidentiality; however, parents and guardians have certain legal rights that limit the rights of minors. Uses a hypothetical case. Offers interventions for empowering minors in…

75 FR 1289 - Minority and Women Inclusion

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-11

... ensure the inclusion of minorities, women, and individuals with disabilities, and businesses owned by... inclusion and utilization of minorities, women, individuals with disabilities, and minority-, women-, and... the inclusion and utilization of minorities, women, individuals with disabilities, and minority...

MINORITY STRESS, POSITIVE IDENTITY DEVELOPMENT, AND DEPRESSIVE SYMPTOMS: IMPLICATIONS FOR RESILIENCE AMONG SEXUAL MINORITY MALE YOUTH

PubMed Central

Bruce, Douglas; Harper, Gary W.; Bauermeister, Jose A.

2015-01-01

Introduction Minority stress processes have been shown to have significant associations with negative mental health outcomes among sexual minority populations. Given that adversity may be experienced growing up as a sexual minority in heteronormative, if not heterosexist, environments, our research on resilience among sexual minority male youth proposes that positive identity development may buffer the effects of a range of minority stress processes. Methods An ethnically diverse sample of 200 sexual minority males ages 16–24 (mean age, 20.9 years) was recruited using mixed recruitment methods. We developed and tested two new measures: concealment stress during adolescence and sexual minority-related positive identity development. We then tested a path model that assessed the effects of minority stressors, positive identity development, and social support on major depressive symptoms. Results Experience of stigma was associated with internalized homophobia (β=.138, p<.05) and major depressive symptoms (β=1.076, OR=2.933, p<.001), and internalized homophobia partially mediated experience’s effects on major depression (β=.773, OR=2.167, p<.001). Concealment stress was associated with positive identity development (β=.155, p<.05) and internalized homophobia (β=.418, p<.001), and positive identity development partially mediated concealment stress’s effects on internalized homophobia (β=−.527, p<.001). Concealment stress demonstrated a direct effect on major depression (β=1.400, OR=4.056, p<.001), and indirect paths to social support through positive identity development. Conclusions With these results, we offer an exploratory model that empirically identifies significant paths among minority stress dimensions, positive identity development, and major depressive symptoms. This study helps further our understanding of minority stress, identity development, and resources of resilience among sexual minority male youth. PMID:26478901

Tribal Minor NSR Synthetic Minor Limit Application Form in EPA's South Central Region

EPA Pesticide Factsheets

This Tribal Minor NSR application form should be used to notify the EPA Region 6 Tribal NSR Permitting Program of requested synthetic minor emission limits associated with a new source general application form.

Sweating responses during heat acclimation and moderate conditioning

NASA Technical Reports Server (NTRS)

Shvartz, E.; Bhattacharya, A.; Sperinde, S. J.; Brock, P. J.; Sciaraffa, D.; Van Beaumont, W.

1979-01-01

Experiments were conducted on ten young male subjects to determine sweating onset, distribution, and patterns as well as the relationships of these responses to body temperature during heat acclimation and moderate conditioning performed in temperate (24 C) conditions. The subjects are randomly assigned to two groups of five subjects each. The experimental period consisted of eight successive days of either graded exercise to exhaustion on a bicycle ergometer in heat (acclimation group) or in a temperate environment (control group). Major conclusions are that (1) acclimation and conditioning result in relatively more sweat rate on the limbs than on the torso, but that these changes are less related to body temperature than torso sweat rate; and (2) sweating sensitivity increases during acclimation and conditioning, but its contribution to heat acclimation is minor.

Disadvantages of Minority Group Membership: The Perspective of a "Nondeprived" Minority Group

ERIC Educational Resources Information Center

Lavender, Abraham D.

1975-01-01

Utilizing a sample of Jewish undergraduate students, evidence is presented to indicate that a minority group which is not deprived materially can nonetheless perceive itself as receiving disadvantages from its minority group status. The most frequently perceived disadvantages (as well as advantages) are enumerated and discussed. (EH)

Heat treatment of bulk gallium arsenide using a phosphosilicate glass cap

NASA Technical Reports Server (NTRS)

Mathur, G.; Wheaton, M. L.; Borrego, J. M.; Ghandhi, S. K.

1985-01-01

n-type bulk GaAs crystals, capped with chemically vapor-deposited phosphosilicate glass, were heat treated at temperatures in the range of 600 to 950 C. Measurements on Schottky diodes and solar cells fabricated on the heat-treated material, after removal of a damaged surface layer, show an increase in free-carrier concentration, in minority-carrier-diffusion length, and in solar-cell short-circuit current. The observed changes are attributed to a removal of lifetime-reducing acceptorlike impurities, defects, or their complexes.

The Importance of Minority Teachers: Student Perceptions of Minority versus White Teachers

ERIC Educational Resources Information Center

Cherng, Hua-Yu Sebastian; Halpin, Peter F.

2016-01-01

The demographic divide between teachers and students is of growing public concern. However, few studies have explicitly addressed the common argument that students, and particularly minority students, have more favorable perceptions of minority versus White teachers. Using data from the Measure of Effective Teaching study, we find that students…

43 CFR 3102.3 - Minors.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Minors. 3102.3 Section 3102.3 Public Lands... INTERIOR MINERALS MANAGEMENT (3000) OIL AND GAS LEASING Qualifications of Lessees § 3102.3 Minors. Leases shall not be acquired or held by one considered a minor under the laws of the State in which the lands...

Reducing heat stress under thermal insulation in protective clothing: microclimate cooling by a 'physiological' method.

PubMed

Glitz, K J; Seibel, U; Rohde, U; Gorges, W; Witzki, A; Piekarski, C; Leyk, D

2015-01-01

Heat stress caused by protective clothing limits work time. Performance improvement of a microclimate cooling method that enhances evaporative and to a minor extent convective heat loss was tested. Ten male volunteers in protective overalls completed a work-rest schedule (130 min; treadmill: 3 × 30 min, 3 km/h, 5% incline) with or without an additional air-diffusing garment (climatic chamber: 25°C, 50% RH, 0.2 m/s wind). Heat loss was supported by ventilating the garment with dry air (600 l/min, ≪5% RH, 25°C). Ventilation leads (M ± SD, n = 10, ventilated vs. non-ventilated) to substantial strain reduction (max. HR: 123 ± 12 b/min vs. 149 ± 24 b/min) by thermal relief (max. core temperature: 37.8 ± 0.3°C vs. 38.4 ± 0.4°C, max. mean skin temperature: 34.7 ± 0.8°C vs. 37.1 ± 0.3°C) and offers essential extensions in performance and work time under thermal insulation. Heat stress caused by protective clothing limits work time. Performance can be improved by a microclimate cooling method that supports evaporative and to a minor extent convective heat loss. Sweat evaporation is the most effective thermoregulatory mechanism for heat dissipation and can be enhanced by insufflating dry air into clothing.

The BCLA Minor: Business, Communication, and Liberal Arts Minor at Towson University

ERIC Educational Resources Information Center

Mahin, Linda

2008-01-01

In this article, the author describes a cross-disciplinary minor that combines elements of business, communication, and the liberal arts. The BCLA Minor enhances employment opportunities and cultural awareness for students with majors in the Colleges of Business and Economics, Fine Arts and Communication, and Liberal Arts by integrating the…

Self-Esteem Comparisons among Intellectually Gifted Minority/Non-Minority Junior High Students.

ERIC Educational Resources Information Center

Legin-Bucell, Cynthia; And Others

Differences in self-esteem between 48 minority and 62 non-minority intellectually gifted and 75 intellectually average junior-high students were assessed using the Coopersmith Self-Esteem Inventory. Results indicated a higher level of self-esteem for the gifted students than for the control group. Significant differences were also found to exist…

Minority stressors, rumination, and psychological distress in monozygotic twins discordant for sexual minority status.

PubMed

Timmins, Liam; Rimes, Katharine A; Rahman, Qazi

2017-11-07

Lesbian, gay, and bisexual (LGB) individuals report higher levels of depression and anxiety than heterosexual people. Genetic factors may be a 'common cause' of sexual minority status and psychological distress. Alternatively, these may be correlated because of non-genetic environmental factors (e.g. minority stressors). This study investigated minority stressors and distress in monozygotic twins discordant for sexual minority status. This design provides a test of the role of non-shared environmental factors while minimizing differences due to genetics. Thirty-eight twin pairs in which one was heterosexual and the other was LGB completed a survey. Differences between twin pairs in minority stressors, rumination, psychological distress, and gender non-conformity were examined. Associations between these variables were also tested. Although there were no significant group differences for distress, LGB twins had higher rumination, a vulnerability factor for distress, than heterosexual co-twins. LGB twins also had higher scores than heterosexual co-twins on expectations of rejection, active concealment, self-stigma, prejudice events, childhood gender non-conformity, and lower scores on sexual orientation disclosure. Differences between twin pairs in rumination were positively associated with differences in acceptance concerns and self-stigma. Finally, self-stigma was positively associated with rumination in the full sample of heterosexual co-twins and microaggressions were positively associated with rumination when looking at exclusively heterosexual co-twins. These results support environmental factors as a causal explanation for disparities in rumination between LGB and heterosexual individuals. These factors likely include minority stressors. Rumination may also be associated with minority stressors in heterosexual MZ co-twins of LGB individuals.

Characterisation of case depth in induction-hardened medium carbon steels based on magnetic minor hysteresis loop measurement technique

NASA Astrophysics Data System (ADS)

He, Cunfu; Yang, Meng; Liu, Xiucheng; Wang, Xueqian; Wu, Bin

2017-11-01

The magnetic hysteresis behaviours of ferromagnetic materials vary with the heat treatment-induced micro-structural changes. In the study, the minor hysteresis loop measurement technique was used to quantitatively characterise the case depth in two types of medium carbon steels. Firstly, high-frequency induction quenching was applied in rod samples to increase the volume fraction of hard martensite to the soft ferrite/pearlite (or sorbite) in the sample surface. In order to determine the effective and total case depth, a complementary error function was employed to fit the measured hardness-depth profiles of induction-hardened samples. The cluster of minor hysteresis loops together with the tangential magnetic field (TMF) were recorded from all the samples and the comparative study was conducted among three kinds of magnetic parameters, which were sensitive to the variation of case depth. Compared to the parameters extracted from an individual minor loop and the distortion factor of the TMF, the magnitude of three-order harmonic of TMF was more suitable to indicate the variation in case depth. Two new minor-loop coefficients were introduced by combining two magnetic parameters with cumulative statistics of the cluster of minor-loops. The experimental results showed that the two coefficients monotonically linearly varied with the case depth within the carefully selected magnetisation region.

Women and Minority Scientists

ERIC Educational Resources Information Center

Vetter, Betty M.

1975-01-01

Offers statistics on the numbers of women and members of minority groups in the sciences. Suggests if women and members of minority groups are to be encouraged to prepare for scientific careers, they must be given the same incentives as offered to men. (CP)

Preferential Heating of Oxygen 5+ Ions by Finite-Amplitude Oblique Alfven Waves

NASA Technical Reports Server (NTRS)

Maneva, Yana G.; Vinas, Adolfo; Araneda, Jamie; Poedts, Stefaan

2016-01-01

Minor ions in the fast solar wind are known to have higher temperatures and to flow faster than protons in the interplanetary space. In this study we combine previous research on parametric instability theory and 2.5D hybrid simulations to study the onset of preferential heating of Oxygen 5+ ions by large-scale finite-amplitude Alfven waves in the collisionless fast solar wind. We consider initially non-drifting isotropic multi-species plasma, consisting of isothermal massless fluid electrons, kinetic protons and kinetic Oxygen 5+ ions. The external energy source for the plasma heating and energization are oblique monochromatic Alfven-cyclotron waves. The waves have been created by rotating the direction of initial parallel pump, which is a solution of the multi-fluid plasma dispersion relation. We consider propagation angles theta less than or equal to 30 deg. The obliquely propagating Alfven pump waves lead to strong diffusion in the ion phase space, resulting in highly anisotropic heavy ion velocity distribution functions and proton beams. We discuss the application of the model to the problems of preferential heating of minor ions in the solar corona and the fast solar wind.

Defining minors' abortion rights.

PubMed

Rhodes, A M

1988-01-01

The right to abortion is confirmed in the Roe versus Wade case, by the US Supreme Court. It is a fundamental right of privacy but not an absolute right, and must consider state interests. During the first trimester of pregnancy abortion is a decision of the woman and her doctor. During the second trimester of pregnancy the state may control the abortion practice to protect the mothers health, and in the last trimester, it may prohibit abortion, except in cases where the mother's life or health are in danger. The states enacted laws, including one that required parents to give written consent for a unmarried minor's abortion. This law was struck down by the US Court, but laws on notification were upheld as long as there was alternative procedures where the minor's interests are upheld. Many of these law have been challenged successfully, where the minor was judged mature and where it served her best interests. The state must enact laws on parental notification that take into consideration basic rights of the minor woman. Health professionals and workers should be aware of these laws and should encourage the minor to let parents in on the decision making process where possible.

11 CFR 110.19 - Contributions by minors.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 11 Federal Elections 1 2010-01-01 2010-01-01 false Contributions by minors. 110.19 Section 110.19... PROHIBITIONS § 110.19 Contributions by minors. An individual who is 17 years old or younger (a Minor) may make... the Minor; (b) The funds, goods, or services contributed are owned or controlled by the Minor, such as...

11 CFR 110.19 - Contributions by minors.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 11 Federal Elections 1 2011-01-01 2011-01-01 false Contributions by minors. 110.19 Section 110.19... PROHIBITIONS § 110.19 Contributions by minors. An individual who is 17 years old or younger (a Minor) may make... the Minor; (b) The funds, goods, or services contributed are owned or controlled by the Minor, such as...

77 FR 18685 - New Animal Drugs for Minor Use and Minor Species

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-28

... HEALTH AND HUMAN SERVICES DEPARTMENT Food and Drug Administration 21 CFR Part 516 New Animal Drugs for Minor Use and Minor Species CFR Correction In Title 21 of the Code of Federal Regulations, Parts 500 to 599, revised as of April 1, 2011, on page 96, in Sec. 516.20, (b)(2) is revised to read as...

FIESTA; Minority Television Programming.

ERIC Educational Resources Information Center

Marshall, Wes; And Others

The suggestions for planning, running, and evaluating minority television programing presented in this handbook are based on the experience and example of the FIESTA project (Tucson, Arizona). After initiating the reader into the topic of minority programing, the document disucsses the following topics: broadcast research, origins of the FIESTA…

Multichoice minority game.

PubMed

Ein-Dor, L; Metzler, R; Kanter, I; Kinzel, W

2001-06-01

The generalization of the problem of adaptive competition, known as the minority game, to the case of K possible choices for each player, is addressed, and applied to a system of interacting perceptrons with input and output units of a type of K-state Potts spins. An optimal solution of this minority game, as well as the dynamic evolution of the adaptive strategies of the players, are solved analytically for a general K and compared with numerical simulations.

Minority Health and Health Disparities

MedlinePlus

... Populations & Co-occurring Disorders » Minority Health and Health Disparities In this Section Underage Drinking College Drinking Women Older Adults Minority Health & Health Disparities Other Psychiatric ...

Mental Health and Minorities.

ERIC Educational Resources Information Center

Meadows, Michelle, Ed.

1997-01-01

This newsletter includes 12 brief articles or news items concerning mental health among minority groups. These address: (1) cultural considerations in treating Asians (reasons why Asians tend not to use mental health services); (2) coping with racial stress (responses to a questionnaire on dealing with racial stress); (3) minority health…

Faster Parameterized Algorithms for Minor Containment

NASA Astrophysics Data System (ADS)

Adler, Isolde; Dorn, Frederic; Fomin, Fedor V.; Sau, Ignasi; Thilikos, Dimitrios M.

The theory of Graph Minors by Robertson and Seymour is one of the deepest and significant theories in modern Combinatorics. This theory has also a strong impact on the recent development of Algorithms, and several areas, like Parameterized Complexity, have roots in Graph Minors. Until very recently it was a common belief that Graph Minors Theory is mainly of theoretical importance. However, it appears that many deep results from Robertson and Seymour's theory can be also used in the design of practical algorithms. Minor containment testing is one of algorithmically most important and technical parts of the theory, and minor containment in graphs of bounded branchwidth is a basic ingredient of this algorithm. In order to implement minor containment testing on graphs of bounded branchwidth, Hicks [NETWORKS 04] described an algorithm, that in time O(3^{k^2}\\cdot (h+k-1)!\\cdot m) decides if a graph G with m edges and branchwidth k, contains a fixed graph H on h vertices as a minor. That algorithm follows the ideas introduced by Robertson and Seymour in [J'CTSB 95]. In this work we improve the dependence on k of Hicks' result by showing that checking if H is a minor of G can be done in time O(2^{(2k +1 )\\cdot log k} \\cdot h^{2k} \\cdot 2^{2h^2} \\cdot m). Our approach is based on a combinatorial object called rooted packing, which captures the properties of the potential models of subgraphs of H that we seek in our dynamic programming algorithm. This formulation with rooted packings allows us to speed up the algorithm when G is embedded in a fixed surface, obtaining the first single-exponential algorithm for minor containment testing. Namely, it runs in time 2^{O(k)} \\cdot h^{2k} \\cdot 2^{O(h)} \\cdot n, with n = |V(G)|. Finally, we show that slight modifications of our algorithm permit to solve some related problems within the same time bounds, like induced minor or contraction minor containment.

Design and development of ultra-wideband 3 dB hybrid coupler for Ion cyclotron resonance frequency heating in tokamak.

PubMed

Yadav, Rana Pratap; Kumar, Sunil; Kulkarni, S V

2014-04-01

Design and development of a high power ultra-wideband, 3 dB tandem hybrid coupler is presented and its application in ICRF heating of the tokamak is discussed. In order to achieve the desired frequency band of 38-112 MHz and 200 kW power handling capability, the 3 dB hybrid coupler is developed using two 3-element 8.34 ± 0.2 dB coupled lines sections in tandem. In multi-element coupled lines, junctions are employed for the joining of coupled elements that produce the undesirable reactance called junction discontinuity effect. The effect becomes prominent in the high power multi-element coupled lines for high frequency (HF) and very high frequency(VHF) applications because of larger structural dimensions. Junction discontinuity effect significantly deteriorates coupling and output performance from the theoretical predictions. For the analysis of junction discontinuity effect and its compensation, a theoretical approach has been developed and generalized for n-element coupled lines section. The theory has been applied in the development of the 3 dB hybrid coupler. The fabricated hybrid coupler has been experimentally characterized using vector network analyzer and obtained results are found in good agreement with developed theory.

Minor elements in Keweenawan lavas, Michigan

USGS Publications Warehouse

Cornwall, H.R.; Rose, H.J.

1957-01-01

The distribution of minor elements in three basaltic flows of the Keweenawan series, of Michigan, is related to differentiation in the flows. Thus, nickel is most abundant in the early differentiates; nickel, chromium, and barium are generally deficient in the pegmatites, which formed late; whereas copper, vanadium, yttrium, and other minor elements are concentrated in the pegmatites. The minor-element content of individual minerals in the Greenstone flow varies markedly from one mineral to another and seems to depend primarily on the presence or absence in the minerals of major elements for which the minor elements can substitute. Minor elements have substituted most readily for those major elements with similar ionic radii. Valence and electronegativity also seem to influence the ease of substitution. The distribution of other minor elements in copper-bearing lodes of the Michigan copper district shows no apparent relation to copper mineralization. ?? 1957.

Demonstrating the Physics Basis for the ITER 15 MA Inductive Discharge on Alcator C-Mod

NASA Astrophysics Data System (ADS)

Kessel, C. E.; Wolfe, S. M.; Hutchinson, I. H.; Hughes, J. W.; Lin, Y.; Ma, Y.; Mikkelsen, D. R.; Poli, F.; Reinke, M. L.; Wukitch, S. J.

2012-10-01

Rampup discharges in C-Mod, matching ITE's current diffusion times show ICRF heating can save V-s but results in only weak effects on the current profile, despite strong modifications of the central electron temperature. Simulation of these discharges with TSC, and TORIC for ICRF, using multiple transport models, do not reproduce the temperature profile evolution, or the experimental internal self-inductance li, by sufficiently large amounts to be unacceptable for projections to ITER operation. For the flattop phase experiments EDA H-modes approach the ITER parameter targets of q95=3, H98=1, n/nGr=0.85, betaN=1.7, and k=1.8, and sustain them similar to a normalized ITER flattop time. The discharges show a degradation of energy confinement at higher densities, but increasing H98 with increasing net power to the plasma. For these discharges intrinsic impurities (B, Mo) provided radiated power fractions of 25-37%. Experiments show the plasma can remain in H-mode in rampdown with ICRF injection, the density will decrease with Ip while in the H-mode, and the back transition occurs when the net power reaches about half the L-H transition power. C-Mod indicates that faster rampdowns are preferable. Work supported by US Dept of Energy under DE-AC02-CH0911466 and DE-FC02-99ER54512.

7 CFR 1753.80 - Minor construction procedure.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 11 2011-01-01 2011-01-01 false Minor construction procedure. 1753.80 Section 1753.80... AGRICULTURE TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Minor Construction § 1753.80 Minor construction procedure. (a) If the borrower performs minor construction financed with loan funds, the borrower...

7 CFR 1753.82 - Minor construction closeout.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 11 2011-01-01 2011-01-01 false Minor construction closeout. 1753.82 Section 1753.82... AGRICULTURE TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Minor Construction § 1753.82 Minor construction closeout. (a) For minor construction inspected by the borrower's engineer, an original and two...

7 CFR 1753.82 - Minor construction closeout.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 11 2010-01-01 2010-01-01 false Minor construction closeout. 1753.82 Section 1753.82... AGRICULTURE TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Minor Construction § 1753.82 Minor construction closeout. (a) For minor construction inspected by the borrower's engineer, an original and two...

The genetic origin of minor histocompatibility antigens.

PubMed

Roopenian, D C; Christianson, G J; Davis, A P; Zuberi, A R; Mobraaten, L E

1993-01-01

The purpose of this study was to elucidate the genetic origin of minor histocompatibility (H) antigens. Toward this end common inbred mouse strains, distinct subspecies, and species of the subgenus Mus were examined for expression of various minor H antigens. These antigens were encoded by the classical minor H loci H-3 and H-4 or by newly identified minor H antigens detected as a consequence of mutation. Both minor H antigens that stimulate MHC class I-restricted cytotoxic T cells (Tc) and antigens that stimulate MHC class II-restricted helper T cells (Th) were monitored. The results suggested that strains of distinct ancestry commonly express identical or cross-reactive antigens. Moreover, a correlation between the lack of expression of minor H antigens and ancestral heritage was observed. To address whether the antigens found on unrelated strains were allelic with the sensitizing minor H antigens or a consequence of antigen cross-reactivity, classical genetic segregation analysis was carried out. Even in distinct subspecies and species, the minor H antigens always mapped to the site of the appropriate minor H locus. Together the results suggest: 1) minor H antigen sequences are evolutionarily stable in that their pace of antigenic change is slow enough to predate subspeciation and speciation; 2) the minor H antigens originated in the inbred strains as a consequence of a rare polymorphism or loss mutation carried in a founder mouse stock that caused the mouse to perceive the wild-type protein as foreign; 3) there is a remarkable lack of antigenic cross-reactivity between the defined minor H antigens and other gene products.

Language, Ethnicity and Education: Case Studies on Immigrant Minority Groups and Immigrant Minority Languages. Multilingual Matters 111.

ERIC Educational Resources Information Center

Broeder, Peter; Extra, Guus

Immigrant minority groups and immigrant minority languages in Europe are viewed from three perspectives (demographic, sociolinguistic, and educational) through case studies. The first part, using a demographic approach, includes research on immigrant minority groups in population statistics of both European Union and English-dominant countries…

How minority members' perceptions of majority members' acculturation preferences shape minority members' own acculturation preferences: evidence from Chile.

PubMed

Zagefka, Hanna; González, Roberto; Brown, Rupert

2011-06-01

Two survey studies were conducted in Chile with members of the indigenous minority group Mapuche (Ns = 566; 394). The aim was to find predictors of minority members' acculturation preferences, especially integration. It was hypothesized that minority members' preferences would depend on their perceptions of what majority members want. Specifically, it was predicted that a perception that majority members want minority members to maintain their original culture would be associated with a greater desire for culture maintenance among minority participants. Further, it was predicted that a perception that majority members want intergroup contact would be associated with a greater desire for contact among minority participants. Finally, it was predicted that a perception that majority members are in favour of both culture maintenance and contact (i.e., integration) would be associated with more support for integration among minority participants. Results bore out these predictions. Theoretical and policy implications are discussed. ©2010 The British Psychological Society.

11 CFR 9002.7 - Minor party.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 11 Federal Elections 1 2011-01-01 2011-01-01 false Minor party. 9002.7 Section 9002.7 Federal Elections FEDERAL ELECTION COMMISSION PRESIDENTIAL ELECTION CAMPAIGN FUND: GENERAL ELECTION FINANCING DEFINITIONS § 9002.7 Minor party. Minor party means a political party whose candidate for the office of...

11 CFR 9002.7 - Minor party.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 11 Federal Elections 1 2010-01-01 2010-01-01 false Minor party. 9002.7 Section 9002.7 Federal Elections FEDERAL ELECTION COMMISSION PRESIDENTIAL ELECTION CAMPAIGN FUND: GENERAL ELECTION FINANCING DEFINITIONS § 9002.7 Minor party. Minor party means a political party whose candidate for the office of...

Assessing Cigarette Sales Rates to Minors.

ERIC Educational Resources Information Center

Jason, Leonard A.; And Others

1992-01-01

Interviews with 24 adolescents, observation of minors using cigarette vending machines, and studies of the attempts of 20 minors to purchase cigarettes over the counter all confirm that it is easy for minors to gain access to cigarettes in Chicago (Illinois). Implications for tobacco purchase laws are discussed. (SLD)

The Vocational Rehabilitation of Minorities [and] Reactions.

ERIC Educational Resources Information Center

Giles, Frank L.; And Others

This paper addresses problems encountered by minorities in accessing the state/federal vocational rehabilitation (VR) system, how minorities have fared in the system, the lack of trained minorities in the VR counseling profession, and a comparison of private-for-profit and state/federal VR programs. Minorities considered include Blacks, Hispanic…

Experimental study of the minority-carrier transport at the polysilicon-monosilicon interface

NASA Astrophysics Data System (ADS)

Neugroschel, A.; Arienzo, M.; Isaac, R. D.; Komem, Y.

1985-04-01

This paper presents the results of an experimental study designed to explore both qualitatively and quantitatively the mechanism of the improved current gain in bipolar transistors with polysilicon emitter contacts. Polysilicon contacts were deposited and heat treated at different conditions. The electrical properties were measured using p-n junction test structures that are much more sensitive to the contact properties than are bipolar transistors. A simple phenomenological model was used to correlate the structural properties with electrical measurements. Possible transport mechanisms are examined and estimates are made about upper bounds on transport parameters in the principal regions of the devices. The main conclusion of this study is that the minority-carrier transport in the polycrystalline silicon is dominated by a highly disordered layer at the polysilicon-monosilicon interface characterized by very low minority-carrier mobility. The effective recombination velocity at the n(+) polysilicon-n(+) monosilicon interface was found to be a strong function of fabrication conditions. The results indicate that the recombination velocity can be much smaller than 10,000 cm/s.

14 CFR 152.419 - Minority business.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Minority business. 152.419 Section 152.419... AIRPORT AID PROGRAM Nondiscrimination in Airport Aid Program § 152.419 Minority business. Each person subject to this subpart is required to comply with the Minority Business Enterprise Regulations of the...

14 CFR 152.419 - Minority business.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Minority business. 152.419 Section 152.419... AIRPORT AID PROGRAM Nondiscrimination in Airport Aid Program § 152.419 Minority business. Each person subject to this subpart is required to comply with the Minority Business Enterprise Regulations of the...

14 CFR 152.419 - Minority business.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Minority business. 152.419 Section 152.419... AIRPORT AID PROGRAM Nondiscrimination in Airport Aid Program § 152.419 Minority business. Each person subject to this subpart is required to comply with the Minority Business Enterprise Regulations of the...

14 CFR 152.419 - Minority business.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Minority business. 152.419 Section 152.419... AIRPORT AID PROGRAM Nondiscrimination in Airport Aid Program § 152.419 Minority business. Each person subject to this subpart is required to comply with the Minority Business Enterprise Regulations of the...

14 CFR 152.419 - Minority business.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Minority business. 152.419 Section 152.419... AIRPORT AID PROGRAM Nondiscrimination in Airport Aid Program § 152.419 Minority business. Each person subject to this subpart is required to comply with the Minority Business Enterprise Regulations of the...

12 CFR 217.21 - Minority interest.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 12 Banks and Banking 2 2014-01-01 2014-01-01 false Minority interest. 217.21 Section 217.21 Banks... OF BOARD-REGULATED INSTITUTIONS Definition of Capital § 217.21 Minority interest. (a) Applicability. For purposes of § 217.20, a Board-regulated institution is subject to the minority interest...

12 CFR 324.21 - Minority interest.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 12 Banks and Banking 5 2014-01-01 2014-01-01 false Minority interest. 324.21 Section 324.21 Banks... ADEQUACY OF FDIC-SUPERVISED INSTITUTIONS Definition of Capital § 324.21 Minority interest. (a) Applicability. For purposes of § 324.20, an FDIC-supervised institution is subject to the minority interest...

Minor burn - first aid - slideshow

MedlinePlus

... page: //medlineplus.gov/ency/presentations/100213.htm Minor burn - first aid - series—Procedure, part 1 To use ... out of 2 Overview To treat a minor burn, run cool water over the area of the ...

Gleanings: The Minority Student Success Project.

ERIC Educational Resources Information Center

Smith, Barbara Leigh; MacGregor, Jean

The Minority Student Success Project (MSSP) initiated in 1989 was designed to improve the recruitment and retention of minority students on campuses in the state of Washington. The results of a questionnaire on minority students administered to all of Washington's community colleges, and data from follow-up interviews, were used to design working…

7 CFR 795.12 - Minor children.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 7 2014-01-01 2014-01-01 false Minor children. 795.12 Section 795.12 Agriculture... PROVISIONS COMMON TO MORE THAN ONE PROGRAM PAYMENT LIMITATION General § 795.12 Minor children. (a) A minor child and his parents or guardian (or other person responsible for him) shall be considered as one...

7 CFR 795.12 - Minor children.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false Minor children. 795.12 Section 795.12 Agriculture... PROVISIONS COMMON TO MORE THAN ONE PROGRAM PAYMENT LIMITATION General § 795.12 Minor children. (a) A minor child and his parents or guardian (or other person responsible for him) shall be considered as one...

7 CFR 795.12 - Minor children.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 7 2013-01-01 2013-01-01 false Minor children. 795.12 Section 795.12 Agriculture... PROVISIONS COMMON TO MORE THAN ONE PROGRAM PAYMENT LIMITATION General § 795.12 Minor children. (a) A minor child and his parents or guardian (or other person responsible for him) shall be considered as one...

7 CFR 795.12 - Minor children.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 7 2011-01-01 2011-01-01 false Minor children. 795.12 Section 795.12 Agriculture... PROVISIONS COMMON TO MORE THAN ONE PROGRAM PAYMENT LIMITATION General § 795.12 Minor children. (a) A minor child and his parents or guardian (or other person responsible for him) shall be considered as one...

7 CFR 795.12 - Minor children.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 7 2012-01-01 2012-01-01 false Minor children. 795.12 Section 795.12 Agriculture... PROVISIONS COMMON TO MORE THAN ONE PROGRAM PAYMENT LIMITATION General § 795.12 Minor children. (a) A minor child and his parents or guardian (or other person responsible for him) shall be considered as one...

31 CFR 360.62 - Payment to minor.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Payment to minor. 360.62 Section 360... BONDS, SERIES I Minors, Incompetents, Aged Persons, Absentees, et al. § 360.62 Payment to minor. If the owner of a savings bond is a minor and the form of registration does not indicate that there is a...

31 CFR 360.62 - Payment to minor.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false Payment to minor. 360.62 Section 360... BONDS, SERIES I Minors, Incompetents, Aged Persons, Absentees, et al. § 360.62 Payment to minor. If the owner of a savings bond is a minor and the form of registration does not indicate that there is a...

31 CFR 353.62 - Payment to minors.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false Payment to minors. 353.62 Section 353... BONDS, SERIES EE AND HH Minors, Incompetents, Aged Persons, Absentees, et al. § 353.62 Payment to minors. If the owner of a savings bond is a minor and the form of registration does not indicate that there...

31 CFR 353.62 - Payment to minors.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Payment to minors. 353.62 Section 353... BONDS, SERIES EE AND HH Minors, Incompetents, Aged Persons, Absentees, et al. § 353.62 Payment to minors. If the owner of a savings bond is a minor and the form of registration does not indicate that there...

Minorities in the Labor Market. Volume III: Metropolitan and Regional Inequalities Among Minorities in the Labor Market.

ERIC Educational Resources Information Center

Wilber, George L.; Hagan, Robert J.

Data are presented on the employment inequalities among color-ethnic minorities in major regions and metropolitan areas in the U.S. Achievements of minorities are summarized in brief profiles of each of eight ethnic minorities. Emphasis is placed on their labor force participation, employment, occupational achievement, mobility, weeks worked, and…

25 CFR 213.11 - Minor lessors.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 25 Indians 1 2011-04-01 2011-04-01 false Minor lessors. 213.11 Section 213.11 Indians BUREAU OF... FIVE CIVILIZED TRIBES, OKLAHOMA, FOR MINING How to Acquire Leases § 213.11 Minor lessors. Where the lessor is a minor, certified copies of letters of guardianship and court orders approving leases must be...

25 CFR 213.11 - Minor lessors.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Minor lessors. 213.11 Section 213.11 Indians BUREAU OF... FIVE CIVILIZED TRIBES, OKLAHOMA, FOR MINING How to Acquire Leases § 213.11 Minor lessors. Where the lessor is a minor, certified copies of letters of guardianship and court orders approving leases must be...

29 CFR 780.320 - Nonlocal minors.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 29 Labor 3 2011-07-01 2011-07-01 false Nonlocal minors. 780.320 Section 780.320 Labor Regulations... Provisions § 780.320 Nonlocal minors. The exemption applies only to migrant or other than local hand harvest... specified minors who work for short periods of several days or weeks without returning daily to their homes...

Investigation of bubbles in arterial heat pipes

NASA Technical Reports Server (NTRS)

Saaski, E. W.

1972-01-01

The behavior of gas occlusions in arterial heat pipes has been studied experimentally and theoretically. Specifically, the gas-liquid system properties, solubility and diffusivity, have been measured from -50 to 100 C for helium and argon in ammonia, Freon-21 (CHC12F), and methanol. Properties values obtained were then used to experimentally test models for gas venting from a heat pipe artery under isothermal conditions (i.e., no-heat flow), although the models, as developed, are also applicable to heat pipes operated at power, with some minor modifications. Preliminary calculations indicated arterial bubbles in a stagnant pipe require from minutes to days to collapse and vent. It has been found experimentally that a gas bubble entrapped within an artery structure has a very long lifetime in many credible situations. This lifetime has an approximately inverse exponential dependence on temperature, and is generally considerably longer for helium than for argon. The models postulated for venting under static conditions were in general quantitative agreement with experimental data. Factors of primary importance in governing bubble stability are artery diameter, artery wall thickness, noncondensible gas partial pressure, and the property group (the Ostwald solubility coefficient multiplied by the gas/liquid diffusivity).

America's Minorities--The Demographics of Diversity.

ERIC Educational Resources Information Center

O'Hare, William P.

1992-01-01

The four largest racial and ethnic minorities--African Americans, Hispanics, Asians/Pacific Islanders, and American Indians--accounted for 25 percent of the U.S. population in 1992. By 2050, these minorities may account for 47 percent of the U.S. population. The U.S. minority population is also becoming more diverse because of high rates of…

12 CFR 3.21 - Minority interest.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 12 Banks and Banking 1 2014-01-01 2014-01-01 false Minority interest. 3.21 Section 3.21 Banks and... Capital § 3.21 Minority interest. (a) Applicability. For purposes of § 3.20, a national bank or Federal savings association is subject to the minority interest limitations in this section if: (1) A consolidated...

40 CFR 49.158 - Synthetic minor source permits.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Synthetic minor source permits. 49.158... Federal Minor New Source Review Program in Indian Country § 49.158 Synthetic minor source permits. You may obtain a synthetic minor source permit under this program to establish a synthetic minor source for...

31 CFR 315.62 - Payment to minors.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Payment to minors. 315.62 Section 315..., D, E, F, G, H, J, AND K, AND U.S. SAVINGS NOTES Minors, Incompetents, Aged Persons, Absentees, et al. § 315.62 Payment to minors. If the owner of a savings bond is a minor and the form of registration does...

31 CFR 315.62 - Payment to minors.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false Payment to minors. 315.62 Section 315..., D, E, F, G, H, J, AND K, AND U.S. SAVINGS NOTES Minors, Incompetents, Aged Persons, Absentees, et al. § 315.62 Payment to minors. If the owner of a savings bond is a minor and the form of registration does...

Counseling Minors Without Parental Consent.

ERIC Educational Resources Information Center

Croxton, Tom A.; And Others

1988-01-01

Examines from legal and psychological perspectives counseling services that are provided to minors without parental knowledge or consent. Explores current mental health agency policies and practices, and makes recommendations regarding the counseling needs and rights of minors. (SKC)

Electromagnetic heating of minor planets in the early solar system

NASA Technical Reports Server (NTRS)

Herbert, F.; Sonett, C. P.

1979-01-01

Electromagnetic processes occurring in the primordial solar system are likely to have significantly affected planetary evolution. In particular, electrical coupling of the kinetic energy of a dense T-Tauri-like solar wind into the interior of the smaller planets could have been a major driver of thermal metamorphism. Accordingly a grid of asteroid models of various sizes and solar distances was constructed using dc transverse magnetic induction theory. Plausible parameterizations with no requirement for a high environmental temperature led to complete melting for Vesta with no melting for Pallas and Ceres. High temperatures were reached in the Pallas model, perhaps implying nonmelting thermal metamorphosis as a cause of its anomalous spectrum. A reversal of this temperature sequence seems implausible, suggesting that the Ceres-Pallas-Vesta dichotomy is a natural outcome of the induction mechanism. Highly localized heating is expected to arise due to an instability in the temperature-controlled current distribution. Localized metamorphosis resulting from this effect may be relevant to the production and evolution of pallasites, the large presumed metal component of S object spectra, and the formation of the lunar magma ocean.

2D modeling of DC potential structures induced by RF sheaths with transverse currents in front of ICRF antenna

NASA Astrophysics Data System (ADS)

Faudot, E.; Heuraux, S.; Colas, L.

2005-09-01

Understanding DC potential generation in front of ICRF antennas is crucial for long pulse high RF power systems. DC potentials are produced by sheath rectification of these RF potentials. To reach this goal, near RF parallel electric fields have to be computed in 3D and integrated along open magnetic field lines to yield a 2D RF potential map in a transverse plane. DC potentials are produced by sheath rectification of these RF potentials. As RF potentials are spatially inhomogeneous, transverse polarization currents are created, modifying RF and DC maps. Such modifications are quantified on a `test map' having initially a Gaussian shape and assuming that the map remains Gaussian near its summit,the time behavior of the peak can be estimated analytically in presence of polarization current as a function of its width r0 and amplitude φ0 (normalized to a characteristic length for transverse transport and to the local temperature). A `peaking factor' is built from the DC peak potential normalized to φ0, and validated with a 2D fluid code and a 2D PIC code (XOOPIC). In an unexpected way transverse currents can increase this factor. Realistic situations of a Tore Supra antenna are also studied, with self-consistent near fields provided by ICANT code. Basic processes will be detailed and an evaluation of the `peaking factor' for ITER will be presented for a given configuration.

2D modeling of DC potential structures induced by RF sheaths with transverse currents in front of ICRF antenna

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

Faudot, E.; Heuraux, S.; Colas, L.

2005-09-26

Understanding DC potential generation in front of ICRF antennas is crucial for long pulse high RF power systems. DC potentials are produced by sheath rectification of these RF potentials. To reach this goal, near RF parallel electric fields have to be computed in 3D and integrated along open magnetic field lines to yield a 2D RF potential map in a transverse plane. DC potentials are produced by sheath rectification of these RF potentials. As RF potentials are spatially inhomogeneous, transverse polarization currents are created, modifying RF and DC maps. Such modifications are quantified on a 'test map' having initially amore » Gaussian shape and assuming that the map remains Gaussian near its summit,the time behavior of the peak can be estimated analytically in presence of polarization current as a function of its width r0 and amplitude {phi}0 (normalized to a characteristic length for transverse transport and to the local temperature). A 'peaking factor' is built from the DC peak potential normalized to {phi}0, and validated with a 2D fluid code and a 2D PIC code (XOOPIC). In an unexpected way transverse currents can increase this factor. Realistic situations of a Tore Supra antenna are also studied, with self-consistent near fields provided by ICANT code. Basic processes will be detailed and an evaluation of the 'peaking factor' for ITER will be presented for a given configuration.« less

Workplace harassment: double jeopardy for minority women.

PubMed

Berdahl, Jennifer L; Moore, Celia

2006-03-01

To date there have been no studies of how both sex and ethnicity might affect the incidence of both sexual and ethnic harassment at work. This article represents an effort to fill this gap. Data from employees at 5 organizations were used to test whether minority women are subject to double jeopardy at work, experiencing the most harassment because they are both women and members of a minority group. The results supported this prediction. Women experienced more sexual harassment than men, minorities experienced more ethnic harassment than Whites, and minority women experienced more harassment overall than majority men, minority men, and majority women.

Recruiting minorities into the profession of epidemiology. Surveying the applicants' mail. American College of Epidemiology Committee on Minority Affairs.

PubMed

Morssink, C B; Kumanyika, S; Tell, G S; Schoenbach, V J

1996-01-01

The underrepresentation in epidemiology of members of racial/ethnic minority groups is greater than in medicine and health fields in general. Using printed recruitment materials, we evaluated the impression that epidemiology programs might make on prospective minority students. Mainstream recruitment materials were solicited from all identifiable U.S. epidemiology programs (n = 70) by requesting copies of typical mailings to prospective students. Of 51 respondents, 46 sent materials that could be analyzed by tabulating and evaluating minority-related content in text and pictures. Materials reflected a generally low-key approach to epidemiology student recruitment. Most minority-related text referred to affirmative action or financial aid and was at the school level rather than specific to the epidemiology programs. Few minority-related epidemiology course titles or research interests were identified. We recommend including more information about epidemiology and its relevance to minority health in mainstream recruitment materials as one possible strategy for increasing the number of minority applicants.

Minority Capital Resource Handbook. A Guide to Raising Capital for Minority Entrepreneurs. Second Edition.

ERIC Educational Resources Information Center

Ewing, Samuel D., Jr.; Maloney, Clifton H. W.

This minority capital resource handbook consists of a guide to raising capital for minority entrepreneurs and a listing of sources that provide such capital. The first section deals with the process of raising capital. The realities of raising capital, intermediaries and financial advisors, and assessing needs are outlined. Factors considered in…

Women and Minorities in Psychology.

ERIC Educational Resources Information Center

Russo, Nancy Felipe; And Others

1981-01-01

Presents data on women and minorities in the field of psychology in terms of representation, subfields, degree level, experience, licensure/certification, employment status, employment setting, income, and membership in graduate psychology faculty. Discusses continuing underrepresentation of minorities and pervasive subfield segregation and pay…

Recruitment of minority students to U.S. epidemiology degree programs. The American College of Epidemiology Committee on Minority Affairs.

PubMed

St George, D M; Schoenbach, V J; Reynolds, G H; Nwangwu, J; Adams-Campbell, L

1997-05-01

African-, Hispanic-, and Native Americans are underrepresented in the field of epidemiology including degree programs. As part of the assessment component of its mandate, the American College of Epidemiology Committee on Minority Affairs conducted a survey of minority recruitment activities of U.S. epidemiology degree programs. The survey, containing questions related to marketing activities, institution infrastructure, financial support, academic offerings, and receptive/supportive environment, was mailed to all programs identified in Episource as offering epidemiology degrees. Separate responses were requested concerning activities at the department and school levels. Fifty-two completed questionnaires were received (response rate of 79%). All but two institutions had at least one activity conducted by either the department or the school. However, all activities were more common at the school- than at the department-level. Indeed, some activities [a written minority student recruitment plan (6% of departments and 52% of schools), personnel with minority recruitment responsibilities (4% of departments and 73% of schools)] were almost exclusively school-sponsored. Although marketing-type activities were the most common minority recruitment tool used by departments, only 21% made visits to minority schools, 17% visited other colleges specifically to recruit minorities, and 12% produced materials targeted to ethnic/racial minorities. Six percent of the departments and 19% of the schools offered financial support (grants, fellowships, scholarships) to almost all underrepresented minority students. Even though individual epidemiology degree programs may not see a need for general recruitment activities in order to maintain the size of their applicant pool, minority-specific recruitment activities should be undertaken to enhance and diversify that pool. We recommend that epidemiology departments develop, adopt, and implement comprehensive written plans for the

Happiness and Sexual Minority Status

PubMed Central

Thomeer, Mieke Beth; Reczek, Corinne

2017-01-01

We used logistic regression on nationally representative data (General Social Survey, N = 10,668 and N = 6,680) to examine how sexual minority status related to happiness. We considered two central dimensions of sexual minority status—sexual behavior and sexual identity. We distinguished between same-sex, both-sex, and different-sex oriented participants. Because individuals transition between sexual behavior categories over the life course (e.g., from both-sex partners to only same-sex partners) and changes in sexual minority status have theoretical associations with well-being, we also tested the effects of transitions on happiness. Results showed that identifying as bisexual, gay, or lesbian, having both male and female partners since age 18, or transitioning to only different-sex partners was negatively related to happiness. Those with only same-sex partners since age 18 or in the past five years had similar levels of happiness as those with only different-sex partners since age 18. Additional tests showed that the majority of these happiness differences became non-significant when economic and social resources were included, indicating that the lower happiness was a product of structural and societal forces. Our findings clearly and robustly underscored the importance of taking a multi-faceted approach to understanding sexuality and well-being, demonstrating that not all sexual minority groups experience disadvantaged happiness. Our study calls for more attention to positive aspects of well-being such as happiness in examinations of sexual minorities and suggests that positive psychology and other happiness subfields should consider the role of sexual minority status in shaping happiness. PMID:27102605

Happiness and Sexual Minority Status.

PubMed

Thomeer, Mieke Beth; Reczek, Corinne

2016-10-01

We used logistic regression on nationally representative data (General Social Survey, N = 10,668 and N = 6680) to examine how sexual minority status related to happiness. We considered two central dimensions of sexual minority status-sexual behavior and sexual identity. We distinguished between same-sex, both-sex, and different-sex-oriented participants. Because individuals transition between sexual behavior categories over the life course (e.g., from both-sex partners to only same-sex partners) and changes in sexual minority status have theoretical associations with well-being, we also tested the associations of transitions with happiness. Results showed that identifying as bisexual, gay, or lesbian, having both male and female partners since age 18, or transitioning to only different-sex partners was negatively related to happiness. Those with only same-sex partners since age 18 or in the past 5 years had similar levels of happiness as those with only different-sex partners since age 18. Additional tests showed that the majority of these happiness differences became non-significant when economic and social resources were included, indicating that the lower happiness was a product of structural and societal forces. Our findings clearly and robustly underscored the importance of taking a multi-faceted approach to understanding sexuality and well-being, demonstrating that not all sexual minority groups experience disadvantaged happiness. Our study calls for more attention to positive aspects of well-being such as happiness in examinations of sexual minorities and suggests that positive psychology and other happiness subfields should consider the role of sexual minority status in shaping happiness.

Mercury induced oxidative stress, DNA damage, and activation of antioxidative system and Hsp70 induction in duckweed (Lemna minor).

PubMed

Zhang, Tingting; Lu, Qianqian; Su, Chunlei; Yang, Yaru; Hu, Dan; Xu, Qinsong

2017-09-01

Mercury uptake and its effects on physiology, biochemistry and genomic stability were investigated in Lemna minor after 2 and 6d of exposure to 0-30μM Hg. The accumulation of Hg increased in a concentration- and duration-dependent manner, and was positively correlated with the leaf damage. Oxidative stress after Hg exposure was evidenced in L. minor by a significant decrease in photosynthetic pigments, an increase in malondialdehyde and lipoxygenase activities (total enzyme activity and isoenzymes activity). Fronds of L. minor exposed to Hg showed an induction of peroxidase, catalase, and ascorbate peroxidase activities (total enzyme activity and some isoenzymes activities). Exposure of L. minor to Hg reduced the activity (total enzyme activity and some isoenzymes activities) of glutathione reductase, and superoxide dismutase. Exposure to Hg produced a transient increase in the content of glutathione and ascorbic acid. The content of dehydroascorbate and oxidized glutathione in L. minor were high during the entire exposure period. Exposure of L. minor to Hg also caused the accumulation of proline and soluble sugars. The amplification of new bands and the absence of normal DNA amplicons in treated plants in the random amplified polymorphic DNA (RAPD) profile indicated that genomic template stability (GTS) was affected by Hg treatment. The accumulation of Hsp70 indicated the occurrence of a heat shock response at all Hg concentrations. These results suggest that L. minor plants were able to cope with Hg toxicity through the activation of various mechanisms involving enzymatic and non-enzymatic antioxidants, up-regulation of proline, and induction of Hsp70. Copyright © 2017 Elsevier Inc. All rights reserved.

Vaporisation of candidate nuclear fuels and targets for transmutation of minor actinides

NASA Astrophysics Data System (ADS)

Gotcu-Freis, P.; Hiernaut, J.-P.; Colle, J.-Y.; Nästrén, C.; Carretero, A. Fernandez; Konings, R. J. M.

2011-04-01

The thermal stability and high temperature behaviour of candidate fuels and targets for transmutation of minor actinides has been investigated. Zirconia-based solid solution, MgO-based CERCER and molybdenum-based CERMET fuels containing Am and/or Pu in various concentrations were heated up to 2700 K in a Knudsen cell coupled with a quadrupole mass spectrometer, to measure their vapour pressure and vapour composition. The results reveal that the vaporisation of the actinides from the samples is not only determined by the thermodynamics of the system but is also related to the dynamic evolution of multi-component mixtures with complex composition or microstructure.

Modelling and simulation of heat pipes with TAIThermIR (Conference Presentation)

NASA Astrophysics Data System (ADS)

Winkelmann, Max E.

2016-10-01

Regarding thermal camouflage usually one has to reduce the surface temperature of an object. All vehicles and installations having a combustion engine usually produce a lot of heat with results on hot spots on the surface which are highly conspicuous. Using heat pipes to transfer this heat to another place on the surface more efficiently might be a way to reduce those hotspots and the overall conspicuity. In a first approach, a model for the Software TAIThermIR was developed to test which parameters of the heat pipes are relevant and what effects can be achieved. It will be shown, that the thermal resistivity of contact zones are quite relevant and the thermal coupling of the engine (source of heat) defines if the alteration of the thermal signature is large or not. Furthermore the impact of the use of heat pipes in relation to surface material is discussed. The influence of different weather scenarios on the change of signatures due to the use of heat pipes is of minor relevance and depends on the choice of the surface material. Finally application issues for real systems are discussed.

Assessment Strategies for Minority Groups.

ERIC Educational Resources Information Center

Sharma, Sarla

1986-01-01

Far-reaching ramifications for minority children of psychological assessment warrants that it be accurate, fair, and valid. This article addresses: (1) problems inherent in standardized testing; (2) a moratorium on intelligence testing; (3) alternate approaches to testing; and (4) guidelines for assessing ethnic minority groups. (LHW)

Sexual Minority-Related Victimization as a Mediator of Mental Health Disparities in Sexual Minority Youth: A Longitudinal Analysis

ERIC Educational Resources Information Center

Burton, Chad M.; Marshal, Michael P.; Chisolm, Deena J.; Sucato, Gina S.; Friedman, Mark S.

2013-01-01

Sexual minority youth (youth who are attracted to the same sex or endorse a gay/lesbian/bisexual identity) report significantly higher rates of depression and suicidality than heterosexual youth. The minority stress hypothesis contends that the stigma and discrimination experienced by sexual minority youth create a hostile social environment that…

Rotation and transport in Alcator C-Mod ITB plasmas

NASA Astrophysics Data System (ADS)

Fiore, C. L.; Rice, J. E.; Podpaly, Y.; Bespamyatnov, I. O.; Rowan, W. L.; Hughes, J. W.; Reinke, M.

2010-06-01

Internal transport barriers (ITBs) are seen under a number of conditions in Alcator C-Mod plasmas. Most typically, radio frequency power in the ion cyclotron range of frequencies (ICRFs) is injected with the second harmonic of the resonant frequency for minority hydrogen ions positioned off-axis at r/a > 0.5 to initiate the ITBs. They can also arise spontaneously in ohmic H-mode plasmas. These ITBs typically persist tens of energy confinement times until the plasma terminates in radiative collapse or a disruption occurs. All C-Mod core barriers exhibit strongly peaked density and pressure profiles, static or peaking temperature profiles, peaking impurity density profiles and thermal transport coefficients that approach neoclassical values in the core. The strongly co-current intrinsic central plasma rotation that is observed following the H-mode transition has a profile that is peaked in the centre of the plasma and decreases towards the edge if the ICRF power deposition is in the plasma centre. When the ICRF resonance is placed off-axis, the rotation develops a well in the core region. The central rotation continues to decrease as long as the central density peaks when an ITB develops. This rotation profile is flat in the centre (0 < r/a < 0.4) but rises steeply in the region where the foot in the ITB density profile is observed (0.5 < r/a < 0.7). A correspondingly strong E × B shear is seen at the location of the ITB foot that is sufficiently large to stabilize ion temperature gradient instabilities that dominate transport in C-Mod high density plasmas.

7 CFR 1753.77 - Methods of minor construction.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 11 2011-01-01 2011-01-01 false Methods of minor construction. 1753.77 Section 1753..., DEPARTMENT OF AGRICULTURE TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Minor Construction § 1753.77 Methods of minor construction. Minor construction may be performed by contract using RUS...

Utilization of Minor Actinides as a Fuel Component for Ultra-Long Life Bhr Configurations: Designs, Advantages and Limitations

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

Dr. Pavel V. Tsvetkov

2009-05-20

This project assessed the advantages and limitations of using minor actinides as a fuel component to achieve ultra-long life Very High Temperature Reactor (VHTR) configurations. Researchers considered and compared the capabilities of pebble-bed and prismatic core designs with advanced actinide fuels to achieve ultra-long operation without refueling. Since both core designs permit flexibility in component configuration, fuel utilization, and fuel management, it is possible to improve fissile properties of minor actinides by neutron spectrum shifting through configuration adjustments. The project studied advanced actinide fuels, which could reduce the long-term radio-toxicity and heat load of high-level waste sent to a geologicmore » repository and enable recovery of the energy contained in spent fuel. The ultra-long core life autonomous approach may reduce the technical need for additional repositories and is capable to improve marketability of the Generation IV VHTR by allowing worldwide deployment, including remote regions and regions with limited industrial resources. Utilization of minor actinides in nuclear reactors facilitates developments of new fuel cycles towards sustainable nuclear energy scenarios.« less

Tobacco Product Use Among Sexual Minority Adults

PubMed Central

Johnson, Sarah E.; Holder-Hayes, Enver; Tessman, Greta K.; King, Brian A.; Alexander, Tesfa; Zhao, Xiaoquan

2016-01-01

Introduction A growing body of evidence reveals higher rates of tobacco use among sexual minority populations relative to non-minority (“straight”) populations. This study seeks to more fully characterize this disparity by examining tobacco use by distinct sexual identities and gender to better understand patterns of: (1) cigarette smoking and smoking history; and (2) use of other tobacco products including cigars, pipes, hookah, e-cigarettes, and smokeless tobacco. Methods Data from the 2012–2013 National Adult Tobacco Survey, a random-digit dialed landline and cellular telephone survey of U.S. adults aged ≥18 years, were analyzed in 2014. A sexual minority category was created by combining gay, lesbian, and bisexual responses, along with those who selected an option for other non-heterosexual identities. Results Smoking prevalence was higher among sexual minority adults (27.4%) than straight adults (17.3%). Cigarette smoking was particularly high among bisexual women (36.0%). Sexual minority women started smoking and transitioned to daily smoking earlier than their straight peers. Use of other tobacco products was higher among sexual minority women: prevalence of e-cigarette (12.4%), hookah (10.3%), and cigar use (7.2%) was more than triple that of their straight female peers (3.4%, 2.5%, and 1.3%, respectively). Likewise, prevalence of sexual minority men’s e-cigarette (7.9%) and hookah (12.8%) use exceeded that of straight men (4.7% and 4.5%, respectively). Conclusions Tobacco use is significantly higher among sexual minority than straight adults, particularly among sexual minority women. These findings underscore the importance of tobacco control efforts designed to reach sexual minorities and highlight the heterogeneity of tobacco use within this population. PMID:26526162

What Minority Employees Really Want.

ERIC Educational Resources Information Center

Mehta, Stephanie N.

2000-01-01

Selections for this list of the nation's best companies for minorities were made based on the company's commitment to diversity at every level, paying particular attention to the upper ranks of the companies. In these companies, ethnic minorities make up 22 percent of the officials and managers. (JOW)

Finding Respondents from Minority Groups

ERIC Educational Resources Information Center

Mier, Nelda; Medina, Alvaro A.; Bocanegra-Alonso, Anabel; Castillo-Ruiz, Octelina; Acosta-Gonzalez, Rosa I.; Ramirez, Jose A.

2006-01-01

The recruitment of respondents belonging to ethnic minorities poses important challenges in social and health research. This paper reflects on the enablers and barriers to recruitment that we encountered in our research work with persons belonging to ethnic minorities. Additionally, we applied the Matching Model of Recruitment, a theoretical…

Performance of thermal barrier coatings in high heat flux environments

NASA Technical Reports Server (NTRS)

Miller, R. A.; Berndt, C. C.

1984-01-01

Thermal barrier coatings were exposed to the high temperature and high heat flux produced by a 30 kW plasma torch. Analysis of the specimen heating rates indicates that the temperature drop across the thickness of the 0.038 cm ceramic layer was about 1100 C after 0.5 sec in the flame. An as-sprayed ZrO2-8%Y2O3 specimens survived 3000 of the 0.5 sec cycles with failing. Surface spalling was observed when 2.5 sec cycles were employed but this was attributed to uneven heating caused by surface roughness. This surface spalling was prevented by smoothing the surface with silicon carbide paper or by laser glazing. A coated specimen with no surface modification but which was heat treated in argon also did not surface spall. Heat treatment in air led to spalling in as early as 2 cycle from heating stresses. Failures at edges were investigated and shown to be a minor source of concern. Ceramic coatings formed from ZrO2-12%Y2O3 or ZrO2-20%Y2O3 were shown to be unsuited for use under the high heat flux conditions of this study.

77 FR 72679 - Minority Enterprise Development Week, 2012

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-05

... Minority Enterprise Development Week, 2012 By the President of the United States of America A Proclamation... of Minority Enterprise Development Week, let us honor the role America's minority-owned businesses... through December 8, 2012, as Minority Enterprise Development Week. I call upon all Americans to celebrate...

It is not just a Minor Thing - A Phenomenological-Hermeneutic Study of Patients' Experiences when afflicted by a Minor Heart Attack and Participating in Cardiac Rehabilitation.

PubMed

Simonÿ, Charlotte P; Dreyer, Pia; Pedersen, Birthe D; Birkelund, Regner

2017-06-01

To improve cardiac care, especially cardiac rehabilitation, patients' perspectives should be better addressed. In Denmark, patients afflicted by a minor heart attack in terms of unstable angina pectoris or non-ST-elevation myocardial infarction are treated in fast-track programmes with subacute treatment in hospital, early discharge and follow-up specialised outpatient cardiac rehabilitation. Knowledge of these patients' experiences of their life situation is essential to develop sufficient care protocols. To gain in-depth understanding of how patients afflicted by a minor heart attack experience their life situation when following cardiac rehabilitation. Focus group interviews and individual interviews were conducted with 11 patients enrolled in the cardiac rehabilitation programme. Data consisted of text in the form of transcribed interviews. A three-phased interpretation inspired by Paul Ricoeur's theory of interpretation was applied. As an overall concept, the patients experienced being forced into a demanding life shaking journey. Three themes emerged: Difficulty accepting the disease: facing the disease is a difficult challenge for the patients, leading to vulnerability and helplessness; Understanding that life has become frail: patients feel shaken as they realise that the disease is chronic and life-threatening; and An altered life: patients must adjust to new limitations in their everyday lives. Patients experience an overall demanding transition when they are afflicted by a minor heat attack, whereby their lives are sweepingly changed. Supporting patients' integrity, which becomes vulnerable during the various stages of transitions, is essential to ensure a healthy outcome. Being together with fellow patients during cardiac rehabilitation is a facilitating factor in the course of transition. © 2016 Nordic College of Caring Science.

Microbial communities involved in biogas production exhibit high resilience to heat shocks.

PubMed

Abendroth, Christian; Hahnke, Sarah; Simeonov, Claudia; Klocke, Michael; Casani-Miravalls, Sonia; Ramm, Patrice; Bürger, Christoph; Luschnig, Olaf; Porcar, Manuel

2018-02-01

We report here the impact of heat-shock treatments (55 and 70 °C) on the biogas production within the acidification stage of a two-stage reactor system for anaerobic digestion and biomethanation of grass. The microbiome proved both taxonomically and functionally very robust, since heat shocks caused minor community shifts compared to the controls, and biogas yield was not decreased. The strongest impact on the microbial profile was observed with a combination of heat shock and low pH. Since no transient reduction of microbial diversity occured after the shock, biogas keyplayers, but also potential pathogens, survived the treatment. All along the experiment, the heat-resistant bacterial profile consisted mainly of Firmicutes, Bacteroidetes and Proteobacteria. Bacteroides and Acholeplasma were reduced after heat shocks. An increase was observed for Aminobacterium. Our results prove the stability to thermal stresses of the microbial communities involved in acidification, and the resilience in biogas production irrespectively of the thermal treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Tobacco sales to minors in Italy.

PubMed

Gallus, Silvano; Tramacere, Irene; Zuccaro, Piergiorgio; Colombo, Paolo; La Vecchia, Carlo

2009-01-01

One of the strategies to control tobacco is to limit purchase of cigarettes to minors. To understand the attitudes of Italian adults towards regulations to prevent minors from purchasing tobacco products, we added specific questions to the annual survey on smoking in Italy. During March-April 2007, we conducted a survey on smoking on 3,057 subjects representative of the Italian population aged > or = 15 years. Two specific questions were included, one investigating the attitudes towards the proposed legislation prohibiting purchase of tobacco to individuals under 18 years of age (instead of 16 years) as a policy to reduce smoking prevalence and consumption. The second question asked whether the current tobacco sales-to-minors law was observed. Overall, 78% of Italians believed that a restriction of the current tobacco sales-to-minors law could be moderately to extremely effective as a strategy to decrease smoking prevalence and consumption. More than 90% of Italians reported that they had never seen in their lifetime a retailer refusing to sell cigarettes to an adolescent or requesting the minor's identification or age. A restriction of the legislation, increasing to 18 years the minimum age for purchasing tobacco, would limit access to tobacco products by minors, only if adopted together with systematic and effective enforcement measures.

Minority Stress across the Career-Lifespan Trajectory

ERIC Educational Resources Information Center

Dispenza, Franco; Brown, Colton; Chastain, Taylor E.

2016-01-01

Sexual minority persons (e.g., lesbian, gay, bisexual, and queer) are likely to encounter "minority stress", such as discrimination, concealment, expectation of rejection, and internalized heterosexism. Minority stress occurs alongside one's lifespan and has considerable implications in the context of the career lifespan trajectory.…

The application of minority stress theory to marijuana use among sexual minority adolescents.

PubMed

Goldbach, Jeremy T; Schrager, Sheree M; Dunlap, Shannon L; Holloway, Ian W

2015-02-01

Previous research indicates that lesbian, gay, and bisexual (LGB) adolescents are at increased risk for substance use, including heightened rates of marijuana use. Minority stress theory suggests that difficult social situations create a state of chronic stress that leads to poor health outcomes for LGB adults; however, the applicability of this model has not been well explored in relation to substance use among LGB adolescents. The current study is a secondary analysis of the OutProud survey, conducted in 2000. The original study used purposive sampling to collect data from 1,911 LGB adolescents (age 12-17) across the United States, and represents the largest known study to explore experiences specific to identifying as LGB, such as homophobia and gay-related victimization. We used structural equation modeling (SEM) to explore the feasibility of applying a minority stress framework to understand marijuana use in this population. The final structural model for marijuana use in the LGB adolescent sample displayed excellent fit and modest explanatory power for marijuana use. Two of the five factors, community connectedness and internalized homophobia, were significantly (p < .05) associated with marijuana use. Findings suggest that minority stress theory may be appropriately applied to marijuana use in this population; however, better measurement of minority stress concepts for LGB adolescents is needed.

Minority Engineering Program Pipeline: A Proposal to Increase Minority Student Enrollment and Retention in Engineering

NASA Technical Reports Server (NTRS)

Charity, Pamela C.; Klein, Paul B.; Wadhwa, Bhushan

1995-01-01

The Cleveland State University Minority Engineering Program Pipeline consist of programs which foster engineering career awareness, academic enrichment, and professional development for historically underrepresented minority studies. The programs involved are the Access to Careers in Engineering (ACE) Program for high school pre-engineering students: the LINK Program for undergraduate students pursuing degree which include engineering; and the PEP (Pre-calculus Enrichment Program) and EPIC (Enrichment Program in Calculus) mathematics programs for undergraduate academic enrichment. The pipeline is such that high school graduates from the ACE Program who enroll at Cleveland State University in pursuit of engineering degrees are admitted to the LINK Program for undergraduate level support. LINK Program students are among the minority participants who receive mathematics enrichment through the PEP and EPIC Programs for successful completion of their engineering required math courses. THese programs are interdependent and share the goal of preparing minority students for engineering careers by enabling them to achieve academically and obtain college degree and career related experience.

18 CFR 16.21 - Operation of projects with a minor or minor part license not subject to sections 14 and 15 of the...

Code of Federal Regulations, 2010 CFR

2010-04-01

... with a minor or minor part license not subject to sections 14 and 15 of the Federal Power Act after... TAKEOVER AND RELICENSING OF LICENSED PROJECTS Projects With Minor and Minor Part Licenses Not Subject to Sections 14 and 15 of the Federal Power Act § 16.21 Operation of projects with a minor or minor part...

18 CFR 16.21 - Operation of projects with a minor or minor part license not subject to sections 14 and 15 of the...

Code of Federal Regulations, 2011 CFR

2011-04-01

... with a minor or minor part license not subject to sections 14 and 15 of the Federal Power Act after... TAKEOVER AND RELICENSING OF LICENSED PROJECTS Projects With Minor and Minor Part Licenses Not Subject to Sections 14 and 15 of the Federal Power Act § 16.21 Operation of projects with a minor or minor part...

75 FR 81395 - Minority and Women Inclusion

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-28

... 2590-AA28 Minority and Women Inclusion AGENCIES: Federal Housing Finance Board; Federal Housing Finance... and the inclusion of women and minorities in all activities. The final rule implements the provisions.... It also requires each regulated entity to establish an Office of Minority and Women Inclusion, or...

75 FR 10446 - Minority and Women Inclusion

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-08

... 2590-AA28 Minority and Women Inclusion AGENCIES: Federal Housing Finance Board; Federal Housing Finance... minority and women inclusion. Section 1116 of the Housing and Economic Recovery Act of 2008 amended section... Loan Banks to promote diversity and the inclusion of women and minorities in all activities...

Analysis and optimization of minor actinides transmutation blankets with regards to neutron and gamma sources

NASA Astrophysics Data System (ADS)

Kooymana, Timothée; Buiron, Laurent; Rimpault, Gérald

2017-09-01

Heterogeneous loading of minor actinides in radial blankets is a potential solution to implement minor actinides transmutation in fast reactors. However, to compensate for the lower flux level experienced by the blankets, the fraction of minor actinides to be loaded in the blankets must be increased to maintain acceptable performances. This severely increases the decay heat and neutron source of the blanket assemblies, both before and after irradiation, by more than an order of magnitude in the case of neutron source for instance. We propose here to implement an optimization methodology of the blankets design with regards to various parameters such as the local spectrum or the mass to be loaded, with the objective of minimizing the final neutron source of the spent assembly while maximizing the transmutation performances of the blankets. In a first stage, an analysis of the various contributors to long and short term neutron and gamma source is carried out while in a second stage, relevant estimators are designed for use in the effective optimization process, which is done in the last step. A comparison with core calculations is finally done for completeness and validation purposes. It is found that the use of a moderated spectrum in the blankets can be beneficial in terms of final neutron and gamma source without impacting minor actinides transmutation performances compared to more energetic spectrum that could be achieved using metallic fuel for instance. It is also confirmed that, if possible, the use of hydrides as moderating material in the blankets is a promising option to limit the total minor actinides inventory in the fuel cycle. If not, it appears that focus should be put upon an increased residence time for the blankets rather than an increase in the acceptable neutron source for handling and reprocessing.

Minors and Sexting: Legal Implications.

PubMed

Lorang, Melissa R; McNiel, Dale E; Binder, Renée L

2016-03-01

Sexting is the sending or forwarding of sexually explicit photographs or videos of the sender or someone known to the sender via cell phone. It has become common practice among young people, as cell phones are being given to adolescents at ever younger ages. Youths often send messages without giving appropriate thought to the content of the images. In studies on the subject, rates of minors who have sent sexual images range from 4 to 25 percent, depending on the age of the youths surveyed, the content of the messages and other factors. Because transferring and viewing sexually explicit material when the subject is a minor can be considered child pornography, there can be serious legal consequences. Several states have enacted legislation to help differentiate between child pornography and sexting by minors. The trend reflected in statutes has been that minors involved in sexting without other exacerbating circumstances should be charged with a less serious offense. There is no clear national consensus on how sexting by minors is adjudicated, and therefore we compared several statutes. Case examples are used to illustrate the range of legal outcomes, from felony charges to no charges. Two sexting episodes that were followed by suicide are described. We also address the role of the forensic mental health professional. © 2016 American Academy of Psychiatry and the Law.

78 FR 1759 - Notice of Approval of Clean Air Act Outer Continental Shelf Minor Source/Title V Minor Permit...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-09

... Outer Continental Shelf Minor Source/Title V Minor Permit Modification Issued to Shell Offshore, Inc. for the Kulluk Conical Drilling Unit AGENCY: United States Environmental Protection Agency (EPA... decision granting Shell Offshore Inc.'s (``Shell'') request for minor modifications of Clean Air Act Outer...

Minority Affairs Department Resource Guide.

ERIC Educational Resources Information Center

American Chemical Society, Washington, DC.

The American Chemical Society (ACS), founded in 1876, is a not-for-profit organization that is recognized as a world leader in fostering scientific education and research and promoting public understanding of science. The ACS Committee on Minority Affairs has a mission to develop and implement programs to support minority involvement in the…

Growing Your Own: Minority Teachers

ERIC Educational Resources Information Center

Singh, Delar K.; Stoloff, David L.

2007-01-01

In the USA, the number of school age children who represent minority backgrounds is rapidly growing. However, despite several efforts, the teaching force remains primarily White. The purpose of this paper is to describe a residential future teachers program in Connecticut which recruits minority rising juniors and seniors from high schools across…

Ethnic Minority Dropout in Economics

ERIC Educational Resources Information Center

Arnold, Ivo J. M.

2013-01-01

This paper investigates the first-year study success of minority students in the bachelor program in economics at Erasmus University Rotterdam. We find that the gap in study success between minority and majority students can be attributed to differences in high school education. Students from similar high school tracks show no significant…

Protecting Minors from Free Speech.

ERIC Educational Resources Information Center

Taylor, Joan Kennedy

1997-01-01

Because the Supreme Court has put severe limits on the use of the concepts of national security and protection of women to justify censorship, the predominant strategy has become censorship to protect minors. This article examines the legal concepts of obscenity and material harmful to minors, restrictions on broadcasting, and challenges raised by…

Evaluation of dispersion strengthened nickel-base alloy heat shields for space shuttle application

NASA Technical Reports Server (NTRS)

Johnson, R., Jr.; Killpatrick, D. H.

1975-01-01

The design, fabrication, and testing of a full-size, full-scale TD Ni-20Cr heat shield test array in simulated mission environments is described along with the design and fabrication of two additional full-size, full-scale test arrays to be tested in flowing gas test facilities at the NASA Langley Research Center. Cost and reusability evaluations of TD Ni-20Cr heat shield systems are presented, and weight estimates of a TD Ni-20Cr heat shield system for use on a shuttle orbiter vehicle are made. Safe-line expectancy of a TD Ni-20Cr heat shield system is assessed. Non-destructive test techniques are evaluated to determine their effectiveness in quality assurance checks of TD Ni-20Cr components such as heat shields, heat shield supports, close-out panels, formed cover strips, and edge seals. Results of tests on a braze reinforced full-scale, subsize panel are included. Results show only minor structural degradation in the main TD Ni-20Cr heat shields of the test array during simulated mission test cycles.

Minority Dropouts: Do Rural, Urban, and Suburban Administrators Perceive Causes Affecting Minorities as Priority Items?

ERIC Educational Resources Information Center

Bull, Kay S.; And Others

This study compared the perceptions of a national sample of urban, suburban, and rural administrators (N=891, a 72% response) about minority dropout indicators to what current research literature identifies as highly-ranked causal variables related to minority dropout rates. The literature review identified the following causes of dropping out,…

PETOM: Preservice Education for Teachers of Minorities.

ERIC Educational Resources Information Center

Kamehameha Journal of Education, 1993

1993-01-01

The paper presents an overview of a two-year program called PETOM (Preservice Education for Teachers of Minorities), which receives funding from the Kamehameha Schools and the University of Hawaii to prepare teachers of underachieving minority children. The program educates teachers who can make school successful for Hawaii's minority students.…

Supporting Women and Minority Faculty

ERIC Educational Resources Information Center

Moody, JoAnn

2004-01-01

Good departmental practices can help women and minority faculty thrive and make the greatest possible contribution to the academic enterprise. Several recent books have explored what is wrong with the current way of doing business. In this article, the author outlines steps to bring U.S. minority and European American women faculty--at both the…

25 CFR 17.5 - Minors represented at hearings.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 25 Indians 1 2011-04-01 2011-04-01 false Minors represented at hearings. 17.5 Section 17.5 Indians... Minors represented at hearings. Minor heirs at law, who by the terms of the will are devised a lesser... approval of the special attorney, be represented at the hearing by guardians ad litem. Such minors 14 years...

25 CFR 17.5 - Minors represented at hearings.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Minors represented at hearings. 17.5 Section 17.5 Indians... Minors represented at hearings. Minor heirs at law, who by the terms of the will are devised a lesser... approval of the special attorney, be represented at the hearing by guardians ad litem. Such minors 14 years...

April Spotlight: National Minority Health Month

Cancer.gov

Each April, we recognize National Minority Health Month and National Minority Cancer Awareness Week. Dr. Peter Ogunbiyi shares how CRCHD’s work is related to the 2017 theme: Bridging Health Equity Across Communities.

Report on Minor Uses of Pesticides

EPA Pesticide Factsheets

This report on minor uses of pesticides was required by Section 31 of the Federal Insecticide, Fungicide and Rodenticide Act. It describes EPA's minor use activities and our partnerships with other federal agencies.

On the influence of the americium isotopic vector on the cooling time of minor actinides bearing blankets in fast reactors

NASA Astrophysics Data System (ADS)

Kooyman, Timothée; Buiron, Laurent; Rimpault, Gerald

2018-05-01

In the heterogeneous minor actinides transmutation approach, the nuclei to be transmuted are loaded in dedicated targets often located at the core periphery, so that long-lived heavy nuclides are turned into shorter-lived fission products by fission. To compensate for low flux level at the core periphery, the minor actinides content in the targets is set relatively high (around 20 at.%), which has a negative impact on the reprocessing of the targets due to their important decay heat level. After a complete analysis of the main contributors to the heat load of the irradiated targets, it is shown here that the choice of the reprocessing order of the various feeds of americium from the fuel cycle depends on the actual limit for fuel reprocessing. If reprocessing of hot targets is possible, it is more interesting to reprocess first the americium feed with a high 243Am content in order to limit the total cooling time of the targets, while if reprocessing of targets is limited by their decay heat, it is more interesting to wait for an increase in the 241Am content before loading the americium in the core. An optimization of the reprocessing order appears to lead to a decrease of the total cooling time by 15 years compared to a situation where all the americium feeds are mixed together when two feeds from SFR are considered with a high reprocessing limit.

JET (3He)-D scenarios relying on RF heating: survey of selected recent experiments

NASA Astrophysics Data System (ADS)

Van Eester, D.; Lerche, E.; Andrew, Y.; Biewer, T. M.; Casati, A.; Crombé, K.; de la Luna, E.; Ericsson, G.; Felton, R.; Giacomelli, L.; Giroud, C.; Hawkes, N.; Hellesen, C.; Hjalmarsson, A.; Joffrin, E.; Källne, J.; Kiptily, V.; Lomas, P.; Mantica, P.; Marinoni, A.; Mayoral, M.-L.; Ongena, J.; Puiatti, M.-E.; Santala, M.; Sharapov, S.; Valisa, M.; JET EFDA contributors

2009-04-01

Recent JET experiments have been devoted to the study of (3He)-D plasmas involving radio frequency (RF) heating. This paper starts by discussing the RF heating efficiency theoretically expected in such plasmas, covering both relevant aspects of wave and of particle dynamics. Then it gives a concise summary of the main conclusions drawn from recent experiments that were either focusing on studying RF heating physics aspects or that were adopting RF heating as a tool to study plasma behavior. Depending on the minority concentration chosen, different physical phenomena are observed. At very low concentration (X[3He] < 1%), energetic tails are formed which trigger MHD activity and result in loss of fast particles. Alfvén cascades were observed and gamma ray tomography indirectly shows the impact of sawtooth crashes on the fast particle orbits. Low concentration (X[3He] < 10%) favors minority heating while for X[3He] Gt 10% electron mode conversion damping becomes dominant. Evidence for the Fuchs et al standing wave effect (Fuchs et al 1995 Phys. Plasmas 2 1637-47) on the absorption is presented. RF induced deuterium tails were observed in mode conversion experiments with large X[3He] (≈18%). As tentative modeling shows, the formation of these tails can be explained as a consequence of wave power absorption by neutral beam particles that efficiently interact with the waves well away from the cold D cyclotron resonance position as a result of their substantial Doppler shift. As both ion and electron RF power deposition profiles in (3He)-D plasmas are fairly narrow—giving rise to localized heat sources—the RF heating method is an ideal tool for performing transport studies. Various of the experiments discussed here were done in plasmas with internal transport barriers (ITBs). ITBs are identified as regions with locally reduced diffusivity, where poloidal spinning up of the plasma is observed. The present know-how on the role of RF heating for impurity transport is

18 CFR 16.19 - Procedures for an existing licensee of a minor hydroelectric power project or of a minor part of...

Code of Federal Regulations, 2010 CFR

2010-04-01

... existing licensee of a minor hydroelectric power project or of a minor part of a hydroelectric power....19 Procedures for an existing licensee of a minor hydroelectric power project or of a minor part of a hydroelectric power project with a license not subject to sections 14 and 15 of the Federal Power Act. (a...

18 CFR 16.19 - Procedures for an existing licensee of a minor hydroelectric power project or of a minor part of...

Code of Federal Regulations, 2014 CFR

2014-04-01

... existing licensee of a minor hydroelectric power project or of a minor part of a hydroelectric power....19 Procedures for an existing licensee of a minor hydroelectric power project or of a minor part of a hydroelectric power project with a license not subject to sections 14 and 15 of the Federal Power Act. (a...

18 CFR 16.19 - Procedures for an existing licensee of a minor hydroelectric power project or of a minor part of...

Code of Federal Regulations, 2013 CFR

2013-04-01

... existing licensee of a minor hydroelectric power project or of a minor part of a hydroelectric power....19 Procedures for an existing licensee of a minor hydroelectric power project or of a minor part of a hydroelectric power project with a license not subject to sections 14 and 15 of the Federal Power Act. (a...

18 CFR 16.19 - Procedures for an existing licensee of a minor hydroelectric power project or of a minor part of...

Code of Federal Regulations, 2012 CFR

2012-04-01

... existing licensee of a minor hydroelectric power project or of a minor part of a hydroelectric power....19 Procedures for an existing licensee of a minor hydroelectric power project or of a minor part of a hydroelectric power project with a license not subject to sections 14 and 15 of the Federal Power Act. (a...

18 CFR 16.19 - Procedures for an existing licensee of a minor hydroelectric power project or of a minor part of...

Code of Federal Regulations, 2011 CFR

2011-04-01

... existing licensee of a minor hydroelectric power project or of a minor part of a hydroelectric power....19 Procedures for an existing licensee of a minor hydroelectric power project or of a minor part of a hydroelectric power project with a license not subject to sections 14 and 15 of the Federal Power Act. (a...

25 CFR 117.6 - Allowance for minors.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 25 Indians 1 2011-04-01 2011-04-01 false Allowance for minors. 117.6 Section 117.6 Indians BUREAU... Allowance for minors. The superintendent may disburse from the surplus funds of an Indian under 21 years of age not to exceed $300 quarterly for the support and maintenance of the minor. Disbursement may be...

Interaction of ICRF Fields with the Plasma Boundary in AUG and JET and Guidelines for Antenna Optimization

NASA Astrophysics Data System (ADS)

Bobkov, V.; Bilato, R.; Braun, F.; Colas, L.; Dux, R.; Van Eester, D.; Giannone, L.; Goniche, M.; Herrmann, A.; Jacquet, P.; Kallenbach, A.; Krivska, A.; Lerche, E.; Mayoral, M.-L.; Milanesio, D.; Monakhov, I.; Müller, H. W.; Neu, R.; Noterdaeme, J.-M.; Pütterich, Th.; Rohde, V.

2009-11-01

W sputtering during ICRF on ASDEX Upgrade (AUG) and temperature rise on JET A2 antenna septa are considered in connection with plasma conditions at the antenna plasma facing components and E‖ near-fields. Large antenna-plasma clearance, high gas puff and low light impurity content are favorable to reduce W sputtering in AUG. The spatial distribution of spectroscopically measured effective W sputtering yields clearly points to the existence of strong E‖ fields at the antenna box ("feeder fields") which dominate over the fields in front of the antenna straps. The picture of E‖ fields, obtained by HFSS code, corroborates the dominant role of E‖ at the antenna box on the formation of sheath-driving RF voltages for AUG. Large antenna-plasma clearance and low gas puff are favorable to reduce septum temperature of JET A2 antennas. Assuming a linear relation between the septum temperature and the sheath driving RF voltage calculated by HFSS, the changes of the temperature with dipole phasing (00ππ, 0ππ0 or 0π0π) are well described by the related changes of the RF voltages. Similarly to the AUG antenna, the strongest E‖ are found at the limiters of the JET A2 antenna for all used dipole phasings and at the septum for the phasings different from 0π0π. A simple general rule can be used to minimize E‖ at the antenna: image currents can be allowed only at the surfaces which do not intersect magnetic field lines at large angles of incidence. Possible antenna modifications generally rely either on a reduction of the image currents, on their short-circuiting by introducing additional conducting surfaces or on imposing the E‖ = 0 boundary condition. On the example of AUG antenna, possible options to minimize the sheath driving voltages are presented.

In-situ crystal structure determination of seifertite SiO 2 at 129 GPa: Studying a minor phase near Earth’s core–mantle boundary

DOE PAGES

Zhang, Li; Popov, Dmitry; Meng, Yue; ...

2016-01-01

Seifertite SiO₂ likely exists as a minor phase near the core–mantle boundary. By simulating the pressure and temperature conditions near the core–mantle boundary, seifertite was synthesized as a minor phase in a coarse-grained, polycrystalline sample coexisting with the (Mg,Fe)SiO₃ post-perovskite (pPv) phase at 129 GPa and 2500 K. Here we report the first in situ single-crystal structure determination and refinement of seifertite at high pressure and after a temperature quench from laser heating. We improved the data coverage of a minor phase from a diamond-anvil cell (DAC) by merging single-crystal data of seifertite from six selected grains that had differentmore » orientations. Observed systematic absences of reflections from the six individual grains allowed only one space group: Pbcn. The refined results of seifertite are in good agreement with the predictions from previous first-principles calculations at high pressure. This approach provides a method for structure determination of a minor phase in a mineral assemblage synthesized under P-T conditions representative of the deep Earth.« less

In-situ crystal structure determination of seifertite SiO 2 at 129 GPa: Studying a minor phase near Earth’s core–mantle boundary

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

Zhang, Li; Popov, Dmitry; Meng, Yue

Seifertite SiO₂ likely exists as a minor phase near the core–mantle boundary. By simulating the pressure and temperature conditions near the core–mantle boundary, seifertite was synthesized as a minor phase in a coarse-grained, polycrystalline sample coexisting with the (Mg,Fe)SiO₃ post-perovskite (pPv) phase at 129 GPa and 2500 K. Here we report the first in situ single-crystal structure determination and refinement of seifertite at high pressure and after a temperature quench from laser heating. We improved the data coverage of a minor phase from a diamond-anvil cell (DAC) by merging single-crystal data of seifertite from six selected grains that had differentmore » orientations. Observed systematic absences of reflections from the six individual grains allowed only one space group: Pbcn. The refined results of seifertite are in good agreement with the predictions from previous first-principles calculations at high pressure. This approach provides a method for structure determination of a minor phase in a mineral assemblage synthesized under P-T conditions representative of the deep Earth.« less

Disproportionate minority contact.

PubMed

Piquero, Alex R

2008-01-01

For many years, notes Alex Piquero, youth of color have been overrepresented at every stage of the U.S. juvenile justice system. As with racial disparities in a wide variety of social indicators, the causes of these disparities are not immediately apparent. Some analysts attribute the disparities to "differential involvement"--that is, to differences in offending by minorities and whites. Others attribute them to "differential selection"--that is, to the fact that the justice system treats minority and white offenders in different ways. Still others believe the explanation lies in a combination of the two. Differential involvement may be important earlier in the judicial process, especially in youths' contacts with police, and may influence differential selection later as individuals make their way through the juvenile justice system. Adjudicating between these options, says Piquero, is difficult and may even be impossible. Asking how much minority overrepresentation is due to differences in offending and how much to differences in processing no longer seems a helpful way to frame the discussion. Piquero urges future research to move beyond the debate over "which one matters more" and seek to understand how each of the two hypotheses can explain both the fact of minority overrepresentation in the juvenile justice system and how best to address it. Piquero cites many sizable gaps in the research and policy-relevant literature. Work is needed especially, he says, in analyzing the first stage of the justice system that juveniles confront: police contacts. The police are a critical part of the juvenile justice decision-making system and are afforded far more discretion than any other formal agent of social control, but researchers have paid surprisingly little attention to contacts between police and citizens, especially juveniles. Piquero notes that some states and localities are undertaking initiatives to reduce racial and ethnic disparities. He urges researchers and

Sexual Minority Stress, Coping, and Physical Health Indicators.

PubMed

Flenar, Delphia J; Tucker, Carolyn M; Williams, Jaime L

2017-12-01

Sexual minorities experience higher rates of several physical health problems compared to their heterosexual counterparts. The present study uses Meyer's Minority Stress Model (Psychological Bulletin, 129(5): 674-697, 2003) to examine physical health indicators among 250 adults who identified as sexual minorities. Study hypotheses include that sexual minority stress is predictive of two physical health indicators (i.e., engagement in a health-promoting lifestyle and number of physical health problems) and that planning (i.e., problem-focused) and social support coping will partially mediate the relationship between sexual minority stress and each physical health indicator. Results showed that as level of sexual minority stress increased, engagement in a health-promoting lifestyle decreased and the number of physical health problems increased. Planning and social support coping did not mediate these relationships; however, as levels of coping increased, engagement in a health-promoting lifestyle increased. These findings have implications for researchers and healthcare professionals in their efforts to promote the physical health of sexual minorities.

[Informed consent of minors--emphasizing the terminally ill].

PubMed

Niv-Yagoda, Adi

2007-06-01

The article deals with the capacity of a minor about to undergo medical treatment to give informed consent, or the right to refuse and withhold such treatment. The paper discusses the applicability of the principles of The Patient's Rights Law to minors, in view of the provisions of the Legal Capacity and Guardianship Law, which categorically denies all minors the option to be involved in or participate in legal decisions, including those concerning their medical treatment. In view of the mental capacity of present day minors, and the principle on which informed consent is based, it seems that the "modern" minor's developing skills surpass those that were attributed to the minor in the 1960s, at the time when the Legal Capacity Law was enacted. It is suggested that it is our legal and moral obligation to modify the current legal state, as minors do not possess the right to participate in decisions concerning their own medical procedures, but for rare specific exceptions. This article was written in line with the practice adopted worldwide concerning the rights available to minors within the medical system, the United Nations Convention on the Rights of the Child, the Report of Judge Rotlevy's Commission and the Terminally Ill Patient Law. The paper attempts to generate a conceptual and cultural change in the attitude of the medical system towards the care of minors and their families.

The Impact of Minority Stress on Mental Health and Substance Use among Sexual Minority Women

ERIC Educational Resources Information Center

Lehavot, Keren; Simoni, Jane M.

2011-01-01

Objective: We examined the direct and indirect impact of minority stress on mental health and substance use among sexual minority women. Method: A combination of snowball and targeted sampling strategies was used to recruit lesbian and bisexual women (N = 1,381) for a cross-sectional, online survey. Participants (M age = 33.54 years; 74% White)…

Persistence among Minority STEM Majors: A Phenomenological Study

NASA Astrophysics Data System (ADS)

Williams-Watson, Stacey

The United States needs to increase the number of science, technology, engineering, and math (STEM) graduates to remain competitive in the global market and maintain national security. Minority students, specifically African-American and Hispanic, are underrepresented in STEM fields. As the minority population continues to grow it is essential that higher education institutions improve minority students' persistence in STEM education. This study examined the problem of minority students' lack of persistence in STEM programs. The purpose of this qualitative transcendental phenomenological study was to describe the lived experiences that minority students perceived as contributing to their persistence in STEM. The central research question was: What are the lived experiences of minority STEM students that have contributed to their persistence in a STEM program? The sub-questions were: a) What led participants to majors in STEM?; b) What contributed to students' success and persistence in STEM?; and c) What advice do students have to offer? The researcher interviewed 12 minority STEM students and uncovered 10 themes that described the lived experiences of minority students' persistence in STEM programs. The themes were 1) Childhood experiences and interests; 2) Positive educational experiences in secondary school; 3) Self- motivation; 4) Positive experiences with professors; 5) Family encouragement and values; 6) Lack of minorities; 7) Lack of educational preparation; 8) The need for financial assistance; 9) Clubs and organizations; and 10) Friends within the major. The significance of these findings is the potential to produce changes in curricula, programs, and retention methods that may improve the persistence of minority students in STEM programs.

Legal protection of informed consent of minors.

PubMed

Osuna, Eduardo

2010-06-01

One of the pillars of healthcare provision is respect for the autonomy of the patient's wishes, which is given substance by the process of obtaining informed consent. Minors deserve special protection, entitled to basic rights and increasingly autonomous as they develop. In certain situations, minors are deemed matures and able to consent to treatment without the involvement of a parent or guardian. The assessment of competence would be based on the child's functional ability, not on age or outcome of the decision. This manuscript includes a brief analysis of legal perspectives on informed consent of minors, and minors' capacities to make medical decisions. Remaining questions of how to evaluate capacity and balance parental and minor autonomy are explored. Considerations on informed consent in different situations as refusing treatment and termination of pregnancy by female children are analyzed.

Minority stress and physical health among sexual minority individuals

PubMed Central

Lehavot, Keren; Meyer, Ilan H.

2013-01-01

This study examined the effects of minority stress on the physical health of lesbians, gay men, and bisexuals (LGBs). Participants (N = 396) completed baseline and one year follow-up interviews. Exposure to stress and health outcomes were assessed with two methods: a subjective self-appraisal method and a method whereby two independent judges externally rated event narratives using standardized criteria. The odds of experiencing a physical health problem at follow-up were significantly higher among LGBs who experienced an externally rated prejudice event during the follow-up period compared to those who did not. This association persisted after adjusting for experiences of general stressful life events that were not related to prejudice. Self-appraised minority stress exposures were not associated with poorer physical health at 1-year follow-up. Prejudice-related stressful life events have a unique deleterious impact on health that persists above and beyond the effect of stressful life events unrelated to prejudice. PMID:23864353

An Examination of the Impact of Minority Status Stress and Impostor Feelings on the Mental Health of Diverse Ethnic Minority College Students

ERIC Educational Resources Information Center

Cokley, Kevin; McClain, Shannon; Enciso, Alicia; Martinez, Mercedes

2013-01-01

This study examined differences in minority status stress, impostor feelings, and mental health in a sample of 240 ethnic minority college students. African Americans reported higher minority status stress than Asian Americans and Latino/a Americans, whereas Asian Americans reported higher impostor feelings. Minority status stress and impostor…

A feasibility study of heat-pipe-cooled leading edges for hypersonic cruise aircraft

NASA Technical Reports Server (NTRS)

Silverstein, C. C.

1971-01-01

A theoretical study of the use of heat pipe structures for cooling the leading edges of hypersonic cruise aircraft was carried out over a Mach number range of 6 to 12. Preliminary design studies showed that a heat pipe cooling structure with a 33-in. chordwise length could maintain the maximum temperature of a 65 deg sweepback wing with a 0.5-in. leading edge radius below 1600 F during cruise at Mach 8. A few relatively minor changes in the steady-state design of the structure were found necessary to insure satisfactory cooling during the climb to cruise speed and altitude. It was concluded that heat pipe cooling is an attractive, feasible technique for limiting leading edge temperatures of hypersonic cruise aircraft.

Minorities and Women and Honors Education.

ERIC Educational Resources Information Center

Harvey, Maria Luisa Alvarez

1986-01-01

Although honors education can be a key to the liberation of women and minorities, both groups continue to be underrepresented, perhaps because bright women and minority students are uncomfortable displaying their talents and adding pressure in an already stressful situation. (MSE)

Designing Educational Programs for Minority Entrepreneurs.

ERIC Educational Resources Information Center

Pride, Michelle L.; Stoffel, Bruce; van Es, J. C.

1997-01-01

When Urbana (Illinois) city government had difficulty recruiting minority contractors, extension educators interviewed 22 minority entrepreneurs, finding they had difficulty meeting requirements and learning about opportunities. Solutions included training for banking, legal, and insurance representatives; workshops to develop bidding skills; and…

Key Issues in Minority Education. Research Directions and Practical Implications.

ERIC Educational Resources Information Center

Ward, Wanda E., Ed.; Cross, Mary M., Ed.

A collection of 10 papers on minority education is presented, with sections on legal aspects of access for minorities, minority faculty and staff, minority graduate education, and standardized testing in the admission of minority students. Papers are as follows: "The Legal Obligation to Secure Access for Minority Students in Higher Education"…

Wave excitation by nonlinear coupling among shear Alfvén waves in a mirror-confined plasma

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

Ikezoe, R., E-mail: ikezoe@prc.tsukuba.ac.jp; Ichimura, M.; Okada, T.

2015-09-15

A shear Alfvén wave at slightly below the ion-cyclotron frequency overcomes the ion-cyclotron damping and grows because of the strong anisotropy of the ion temperature in the magnetic mirror configuration, and is called the Alfvén ion-cyclotron (AIC) wave. Density fluctuations caused by the AIC waves and the ion-cyclotron range of frequencies (ICRF) waves used for ion heating have been detected using a reflectometer in a wide radial region of the GAMMA 10 tandem mirror plasma. Various wave-wave couplings are clearly observed in the density fluctuations in the interior of the plasma, but these couplings are not so clear in themore » magnetic fluctuations at the plasma edge when measured using a pick-up coil. A radial dependence of the nonlinearity is found, particularly in waves with the difference frequencies of the AIC waves; bispectral analysis shows that such wave-wave coupling is significant near the core, but is not so evident at the periphery. In contrast, nonlinear coupling with the low-frequency background turbulence is quite distinct at the periphery. Nonlinear coupling associated with the AIC waves may play a significant role in the beta- and anisotropy-limits of a mirror-confined plasma through decay of the ICRF heating power and degradation of the plasma confinement by nonlinearly generated waves.« less

Effect of minor chemistry elements on GTA weld fusion zone characteristics of a commercial grade titanium

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

Marya, S.K.

1996-06-01

Gas Tungsten Arc Welding (GTAW) is the most common technique employed in the fabrication of rolled thin tubes. One of the major manufacturing problems concerns the stability of weld fusion zone on materials from different casts, notwithstanding stringent monitoring of the process parameters -- current, voltage and travel speed. These parameters determine the theoretical weld heat and are expected to control the instantaneous mass of melt. According to the data compiled by Sahoo et al., oxygen is known to reduce the surface tension of most of the metals. However, investigations on the role of minor changes in concentrations of elementsmore » like sulphur, oxygen, selenium, bismuth, aluminium, and titanium in steels have very often attributed the cast to cast variations to different temperature gradients of surface tension over the weldpool. To the author`s knowledge, no reported work so far has revealed changing weld profiles in autogeneous mechanized GTA welds on titanium due to minor composition changes.« less

Stagnation Region Heat Transfer: The Influence of Turbulence Parameters, Reynolds Number and Body Shape

NASA Technical Reports Server (NTRS)

Vanfossen, G. James; Simoneau, Robert J.

1994-01-01

The effect of velocity gradient on stagnation region heat transfer augmentation by free stream turbulence was investigated. Heat transfer was measured in the stagnation region of four models with elliptical leading edges with ratios of major to minor axes of 1:1, 1.5:1, 2.25:1, and 3:1. Four geometrically similar, square bar, square mesh, biplane grids were used to generate free stream turbulence with different intensities and length. Heat transfer measurements were made for the following ranges of parameters: Reynolds number, based on leading edge diameter, 37,000 to 228,000; dimensionless leading edge velocity gradient, 1.20 to 1.80; turbulence intensity, 1.1 to 15.9%; and length scale to leading edge diameter ratio, 0.05 to 0.30. Stagnation point heat transfer augmentation by free stream turbulence can be predicted using a modified version of a previously developed correlation for a circular leading edge. Heat transfer augmentation was independent of body shape at the stagnation point. The heat transfer distribution down-stream from the stagnation point can be predicted using the normalized laminar heat transfer distribution.

Minor Consent and Delivery of Adolescent Vaccines

PubMed Central

Ford, Carol A.; Skiles, Martha P.; English, Abigail; Cai, Jianwen; Agans, Robert P.; Stokley, Shannon; Markowitz, Lauri; Koumans, Emilia H.

2016-01-01

Purpose To explore whether, and to what extent, minor consent influences adolescent vaccine delivery in the United States. Methods A telephone survey was completed by 263 professionals with responsibilities for adolescent health care and/or vaccination in 43 states. Measures included perceived frequency of unaccompanied minor visits and perceived likelihood of vaccine delivery to unaccompanied minors in hypothetical scenarios that varied by adolescent age, vaccine type, visit type, and clinical setting. Results Among the 76 respondents most familiar with private primary care clinics, 47.1% reported perceptions that 17-year-old patients often present without a parent/legal guardian. Among the 104 respondents most familiar with public primary care clinics, 56.7% reported that 17-year-old patients often present alone. In response to hypothetical scenarios, approximately 30% of respondents familiar with private clinics and 50% of respondents familiar with public clinics reported perceptions that unaccompanied 17-year-old adolescents would not receive influenza, Tdap, or human papillomavirus vaccines during routine check-ups because they could not provide consent. Perceived likelihood of unaccompanied minors receiving vaccines when seen for confidential services in primary care, sexually transmitted disease, and Title X/family planning clinics varied significantly by vaccine type and clinical setting. On average, respondents reported that they would support minors having the ability to self-consent for vaccines at age 14. Conclusions The inability of minors to consent for vaccines is likely one barrier to vaccination. Interventions to increase adolescent vaccination should consider strategies that increase the ability of unaccompanied minors, particularly older minors, to receive vaccines within the context of legal, ethical, and professional guidelines. PMID:24074605

Sexual minority reflections on their psychotherapy experiences.

PubMed

Quiñones, Timothy J; Woodward, Eva N; Pantalone, David W

2017-03-01

Sexual minority (lesbian, gay, bisexual, queer) individuals are regular consumers of psychotherapy, and are more likely to utilize psychotherapy than heterosexually identified individuals. However, there is scant research on sexual minority clients examining their perceptions of therapists' efforts to work successfully with them. We examined the experiences reported by sexual minority individuals in psychotherapy (N = 77), utilizing an Internet-based survey that asked open-ended questions such as, "How did your therapist address your sexual orientation?" Using directed content analysis, we derived 19 repeating ideas, which we categorized into five major themes and two overarching concepts, including: (a) participants reported appreciating general person-centered psychotherapy competencies (e.g., active listening, validation, Socratic questioning) and (b) participants reported that various aspects of sexual orientation (e.g., therapist sexual identity, therapist knowledge about sexual minority populations) are relevant to their experiences in therapy and should be addressed directly by therapists. Results indicated that clients want generally competent therapists who understand that a sexual minority identity is only one part of a client's overall identity and not a defining characteristic or psychopathological. We explicate themes and representative quotes, and provide preliminary recommendations for therapists working with sexual minority clients.

Alcohol-Related Problems among Sexual Minority Women

PubMed Central

Hughes, Tonda

2012-01-01

In this article I describe the historical context for research on sexual minority women’s drinking, including the age-old tendency to link homosexuality and alcoholism; I summarize gaps and limitations that characterized much of the research on sexual minority women’s drinking over the past several decades; and I review recent literature to highlight progress in the field—with a particular focus on my own research related to risk and protective factors for heavy drinking and drinking-related problems among sexual minority women. I conclude with a discussion of barriers to treatment for sexual minority women and recommendations for substance abuse treatment providers. PMID:22470226

Linguistic Minorities in Canada and Health

PubMed Central

Bouchard, Louise; Desmeules, Martin

2013-01-01

Official language minorities (Francophones outside of Quebec and Anglophones in Quebec) make up about 6.4% of the Canadian population. Even though the Canadian constitution gives legal equality status to French and English, there is still room to ask if this equality is maintained in the health sector. In other words, do Francophone and Anglophone communities of Canada have the same health profiles regardless of their minority or majority status? Do they have access to the same health services and in the same conditions? The objective of this paper is to identify the health issues associated with belonging to a linguistic minority. Our research allows us to highlight the social and health disparities that can be attributed to belonging to a minority. In the Canadian context, which has two official languages, an equitable health policy will have to take into consideration language as a determinant of health. PMID:24289938

Gamma-ray spectrometry in the field: Radioactive heat production in the Central Slovakian Volcanic Zone

NASA Astrophysics Data System (ADS)

Harley, Thomas L.; Westaway, Rob; McCay, Alistair T.

2017-05-01

We report 62 sets of measurements from central-southern Slovakia, obtained using a modern portable gamma-ray spectrometer, which reveal the radioactive heat production in intrusive and extrusive igneous rocks of the Late Cenozoic Central Slovakian Volcanic Zone. Sites in granodiorite of the Štiavnica pluton are thus shown to have heat production in the range 2.2-4.9 μW m- 3, this variability being primarily a reflection of variations in content of the trace element uranium. Sites in dioritic parts of this pluton have a lower, but overlapping, range of values, 2.1-4.4 μW m- 3. Sites that have been interpreted in adjoining minor dioritic intrusions of similar age have heat production in the range 1.4-3.3 μW m- 3. The main Štiavnica pluton has zoned composition, with potassium and uranium content and radioactive heat production typically increasing inward from its margins, reflecting variations observed in other granodioritic plutons elsewhere. It is indeed possible that the adjoining dioritic rocks, hitherto assigned to other minor intrusions of similar age, located around the periphery of the Štiavnica pluton, in reality provide further evidence for zonation of the same pluton. The vicinity of this pluton is associated with surface heat flow 40 mW m- 2 above the regional background. On the basis of our heat production measurements, we thus infer that the pluton has a substantial vertical extent, our preferred estimate for the scale depth for its downward decrease in radioactive heat production being 8 km. Nonetheless, this pluton lacks any significant negative Bouguer gravity anomaly. We attribute this to the effect of the surrounding volcanic caldera, filled with relatively low-density lavas, 'masking' the pluton's own gravity anomaly. We envisage that emplacement occurred when the pluton was much hotter, and thus of lower density, than at present, its continued uplift, evident from the local geomorphology, being the isostatic consequence of localized erosion

Short Duration Heat Acclimation in Australian Football Players

PubMed Central

Kelly, Monica; Gastin, Paul B.; Dwyer, Daniel B; Sostaric, Simon; Snow, Rodney J.

2016-01-01

This study examined if five sessions of short duration (27 min), high intensity, interval training (HIIT) in the heat over a nine day period would induce heat acclimation in Australian football (AF) players. Fourteen professional AF players were matched for VO2peak (mL·kg-1·min-1) and randomly allocated into either a heat acclimation (Acc) (n = 7) or Control (Con) group (n = 7). The Acc completed five cycle ergometer HIIT sessions within a nine day period on a cycle ergometer in the heat (38.7 ± 0.5 °C; 34.4 ± 1.3 % RH), whereas Con trained in thermo-neutral conditions (22.3 ± 0.2 °C; 35.8 ± 0. % RH). Four days prior and two days post HIIT participants undertook a 30 min constant load cycling test at 60% V̇O2peak in the heat (37.9 ± 0.1 °C; 28.5 ± 0.7 % RH) during which VO2, blood lactate concentration ([Lac-]), heart rate (HR), rating of perceived exertion (RPE), thermal comfort, core and skin temperatures were measured. Heat acclimation resulted in reduced RPE, thermal comfort and [Lac-] (all p < 0.05) during the submaximal exercise test in the heat. Heart rate was lower (p = 0.007) after HIIT, in both groups. Heat acclimation did not influence any other measured variables. In conclusion, five short duration HIIT sessions in hot dry conditions induced limited heat acclimation responses in AF players during the in-season competition phase. In practice, the heat acclimation protocol can be implemented in a professional team environment; however the physiological adaptations resulting from such a protocol were limited. Key points Some minor heat acclimation adaptations can be induced in professional AF players with five 27 min non-consecutive, short duration HIIT sessions in the heat. The heat acclimation protocol employed in this study was able to be implemented in a professional team sport environment during an actual competitive season. Elevating and maintaining a high core temperature sufficient for heat acclimation likely requires a longer heat

Short Duration Heat Acclimation in Australian Football Players.

PubMed

Kelly, Monica; Gastin, Paul B; Dwyer, Daniel B; Sostaric, Simon; Snow, Rodney J

2016-03-01

This study examined if five sessions of short duration (27 min), high intensity, interval training (HIIT) in the heat over a nine day period would induce heat acclimation in Australian football (AF) players. Fourteen professional AF players were matched for VO2peak (mL·kg(-1)·min(-1)) and randomly allocated into either a heat acclimation (Acc) (n = 7) or Control (Con) group (n = 7). The Acc completed five cycle ergometer HIIT sessions within a nine day period on a cycle ergometer in the heat (38.7 ± 0.5 °C; 34.4 ± 1.3 % RH), whereas Con trained in thermo-neutral conditions (22.3 ± 0.2 °C; 35.8 ± 0. % RH). Four days prior and two days post HIIT participants undertook a 30 min constant load cycling test at 60% V̇O2peak in the heat (37.9 ± 0.1 °C; 28.5 ± 0.7 % RH) during which VO2, blood lactate concentration ([Lac(-)]), heart rate (HR), rating of perceived exertion (RPE), thermal comfort, core and skin temperatures were measured. Heat acclimation resulted in reduced RPE, thermal comfort and [Lac(-)] (all p < 0.05) during the submaximal exercise test in the heat. Heart rate was lower (p = 0.007) after HIIT, in both groups. Heat acclimation did not influence any other measured variables. In conclusion, five short duration HIIT sessions in hot dry conditions induced limited heat acclimation responses in AF players during the in-season competition phase. In practice, the heat acclimation protocol can be implemented in a professional team environment; however the physiological adaptations resulting from such a protocol were limited. Key pointsSome minor heat acclimation adaptations can be induced in professional AF players with five 27 min non-consecutive, short duration HIIT sessions in the heat.The heat acclimation protocol employed in this study was able to be implemented in a professional team sport environment during an actual competitive season.Elevating and maintaining a high core temperature sufficient for heat acclimation likely requires a longer heat

Sexual Minority Disparities in Substance Use Willingness Among Youth.

PubMed

Gamarel, Kristi E; Mereish, Ethan H; Colby, Suzanne M; Barnett, Nancy P; Hayes, Kerri; Jackson, Kristina M

2018-01-02

Disparities in substance use have been observed in sexual minority youth, but less is known about willingness to use substances, an important precursor to actual use. The goal of this study was to examine willingness to use cigarettes, alcohol, and marijuana among sexual minority youth compared to their non-sexual minority counterparts using both cross-sectional and longitudinal data. The present study drew on two waves (Times 1 and 2; 6 months apart) of data collected during high school as part of a prospective study of substance use initiation and progression in Rhode Island. At Time 1, participants (N = 443) ranged in age from 15 to 20 years (M age = 16.7 years, 26.6% sexual minority, 59.5% female, 72.0% White). Participants self-reported their sexual identity and attraction, lifetime use of alcohol, cigarettes and marijuana, and cigarette, alcohol, and marijuana use willingness (i.e., if offered by a best friend or group of friends). In cross-sectional multivariate regression models, sexual minority youth were more likely to report willingness to use cigarettes (p <.05) and marijuana (p <.01) compared to their non-sexual minority counterparts. Longitudinal multivariate regression models revealed that sexual minorities were only significantly more likely to report cigarette willingness at Time 2 compared to their non-sexual minority counterparts (p <.01). There were no significant differences in alcohol use willingness in multivariable cross-sectional or longitudinal models by sexual minority status. Sexual minority youth reported more willingness than non-sexual minority youth to use substances offered by peers; however, longitudinal analyses revealed that peers appear to play a role only in willingness to smoke cigarettes for these youth, and thus peer influence may be a contributing factor in explaining tobacco-related disparities among sexual minority youth. Given that stigma and peer groups may a particular risk factor for tobacco among sexual minority

Glancing angle RF sheaths

NASA Astrophysics Data System (ADS)

D'Ippolito, D. A.; Myra, J. R.

2013-10-01

RF sheaths occur in tokamaks when ICRF waves encounter conducting boundaries. The sheath plays an important role in determining the efficiency of ICRF heating, the impurity influxes from the edge plasma, and the plasma-facing component damage. An important parameter in sheath theory is the angle θ between the equilibrium B field and the wall. Recent work with 1D and 2D sheath models has shown that the rapid variation of θ around a typical limiter can lead to enhanced sheath potentials and localized power deposition (hot spots) when the B field is near glancing incidence. The physics model used to obtain these results does not include some glancing-angle effects, e.g. possible modification of the angular dependence of the Child-Langmuir law and the role of the magnetic pre-sheath. Here, we report on calculations which explore these effects, with the goal of improving the fidelity of the rf sheath BC used in analytical and numerical calculations. Work supported by US DOE grants DE-FC02-05ER54823 and DE-FG02-97ER54392.

RF sheaths for arbitrary B field angles

NASA Astrophysics Data System (ADS)

D'Ippolito, Daniel; Myra, James

2014-10-01

RF sheaths occur in tokamaks when ICRF waves encounter conducting boundaries and accelerate electrons out of the plasma. Sheath effects reduce the efficiency of ICRF heating, cause RF-specific impurity influxes from the edge plasma, and increase the plasma-facing component damage. The rf sheath potential is sensitive to the angle between the B field and the wall, the ion mobility and the ion magnetization. Here, we obtain a numerical solution of the non-neutral rf sheath and magnetic pre-sheath equations (for arbitrary values of these parameters) and attempt to infer the parametric dependences of the Child-Langmuir law. This extends previous work on the magnetized, immobile ion regime. An important question is how the rf sheath voltage distributes itself between sheath and pre-sheath for various B field angles. This will show how generally previous estimates of the rf sheath voltage and capacitance were reasonable, and to improve the RF sheath BC. Work supported by US DOE grants DE-FC02-05ER54823 and DE-FG02-97ER54392.

Minority Population Concentration and Earnings: Evidence from Fixed-Effects Models

ERIC Educational Resources Information Center

Johnson, Kecia; Pais, Jeremy; South, Scott J.

2012-01-01

Consistent with the hypothesis that heightened visibility and competition lead to greater economic discrimination against minorities, countless studies have observed a negative association between minority population concentration and minority socioeconomic attainment. But minorities who reside in areas with high minority concentration are likely…

PAHs molecules and heating of the interstellar gas

NASA Technical Reports Server (NTRS)

Verstraete, Laurent; Leger, Alain; Dhendecourt, Louis B.; Dutuit, O.; Defourneau, D.

1989-01-01

Until now it has remained difficult to account for the rather high temperatures seen in many diffuse interstellar clouds. Various heating mechanisms have been considered: photoionization of minor species, ionization of H by cosmic rays, and photoelectric effect on small grains. Yet all these processes are either too weak or efficient under too restricting conditions to balance the observed cooling rates. A major heat source is thus still missing in the thermal balance of the diffuse gas. Using photoionization cross sections measured in the lab, it was shown that in order to balance the observed cooling rates in cold diffuse clouds (T approx. 80 K) the PAHs would have to contain 15 percent of the cosmic abundance of carbon. This value does not contradict the former estimation of 6 percent deduced from the IR emission bands since this latter is to be taken as a lower limit. Further, it was estimated that the contribution to the heating rate due to PAH's in a warm HI cloud, assuming the same PAH abundance as for a cold HI cloud, would represent a significant fraction of the value required to keep the medium in thermal balance. Thus, photoionization of PAHs might well be a major heat source for the cold and warm HI media.

Disparities in health system input between minority and non-minority counties and their effects on maternal mortality in Sichuan province of western China.

PubMed

Ren, Yan; Qian, Ping; Duan, Zhanqi; Zhao, Ziling; Pan, Jay; Yang, Min

2017-09-29

The maternal mortality rate (MMR) markedly decreased in China, but there has been a significant imbalance among different geographic regions (east, central and west regions), and the mortality in the western region remains high. This study aims to examine how much disparity in the health system and MMR between ethnic minority and non-minority counties exists in Sichuan province of western China and measures conceivable commitments of the health system determinants of the disparity in MMR. The MMR and health system data of 67 minority and 116 non-minority counties were taken from Sichuan provincial official sources. The 2-level Poisson regression model was used to identify health system determinants. A series of nested models with different health system factors were fitted to decide contribution of each factor to the disparity in MMR. The MMR decreased over the last decade, with the fastest declining rate from 2006 to 2010. The minority counties experienced higher raw MMR in 2002 than non-minority counties (94.4 VS. 58.2), which still remained higher in 2014 (35.7 VS. 14.3), but the disparity of raw MMR between minority and non-minority counties decreased from 36.2 to 21.4. The better socio-economic condition, more health human resources and higher maternal health care services rate were associated with lower MMR. Hospital delivery rate alone explained 74.5% of the difference in MMR between minority and non-minority counties. All health system indicators together explained 97.6% of the ethnic difference in MMR, 59.8% in the change trend, and 66.3% county level variation respectively. Hospital delivery rate mainly determined disparity in MMR between minority and non-minority counties in Sichuan province. Increasing hospital birth rates among ethnic minority counties may narrow the disparity in MMR by more than two-thirds of the current level.

Healthcare law in France: towards healthcare emancipation for minors.

PubMed

Rougé-Maillart, C; Jousset, N; Penneau, M

2007-01-01

In France, since 1974 the rights of minors have been gaining ground. The first provisions to this end concerned medical acts in relation to the minor's sexuality (contraceptives and pregnancy termination). The law dated March 4, 2002, relating to patients' rights, gave more scope to this movement, by widening minors' rights so that they could demand confidentiality with regard to their parents. The minor's exercising of these rights can pose a lot of problems. In French law, parental authority is the main representation of the minor. The medical doctor treating a minor must obtain parental authorization. However, the public healthcare code provides that the doctor can override parental wishes during some situations (emergency; parents refuse). But these situations are exceptional. Since 2002, the legislator has gone further, by allowing the doctor to grant requests for care by the minor without parental authorization. However, parental authority remains the normal framework for the protection of a minor. The doctor will have to judge the reasoning and motives of a minor requesting confidentiality regarding their parents in order to decide whether he should grant or refuse care in such conditions.

Minority Women and Advocacy for Women's Health

PubMed Central

Kumanyika, Shiriki K.; Morssink, Christiaan B.; Nestle, Marion

2001-01-01

US minority health issues involve racial/ethnic disparities that affect both women and men. However, women's health advocacy in the United States does not consistently address problems specific to minority women. The underlying evolution and political strength of the women's health and minority health movements differ profoundly. Women of color comprise only one quarter of women's health movement constituents and are, on average, socioeconomically disadvantaged. Potential alliances may be inhibited by vestiges of historical racial and social divisions that detract from feelings of commonality and mutual support. Nevertheless, insufficient attention to minority women's issues undermines the legitimacy of the women's health movement and may prevent important advances that can be achieved only when diversity is fully considered. PMID:11527764

Resume Writing and the Minority Student.

ERIC Educational Resources Information Center

Davis, Barbara D.; Muir, Clive

2003-01-01

Discusses personal observations of how minority students grapple with the resume writing challenge. Examines the parts of the resume that could prove problematic to minority students. Describes perceptions of two human resource managers when given a prototype resume that removed ethnic identifiers. Discusses how business communication educators…

14 CFR 1214.106 - Minor delays.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Space Shuttle Flights of Payloads for Non-U.S. Government, Reimbursable Customers § 1214.106 Minor delays. NASA will attempt to accommodate customer requested minor launch delays. Such delays will... will require NASA's approval and will result in an additional charge as established in the launch...

14 CFR 1214.106 - Minor delays.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Space Shuttle Flights of Payloads for Non-U.S. Government, Reimbursable Customers § 1214.106 Minor delays. NASA will attempt to accommodate customer requested minor launch delays. Such delays will... will require NASA's approval and will result in an additional charge as established in the launch...

14 CFR 1214.106 - Minor delays.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Space Shuttle Flights of Payloads for Non-U.S. Government, Reimbursable Customers § 1214.106 Minor delays. NASA will attempt to accommodate customer requested minor launch delays. Such delays will... will require NASA's approval and will result in an additional charge as established in the launch...

14 CFR 1214.106 - Minor delays.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Space Shuttle Flights of Payloads for Non-U.S. Government, Reimbursable Customers § 1214.106 Minor delays. NASA will attempt to accommodate customer requested minor launch delays. Such delays will... will require NASA's approval and will result in an additional charge as established in the launch...

42 CFR 2.14 - Minor patients.

Code of Federal Regulations, 2012 CFR

2012-10-01

... ALCOHOL AND DRUG ABUSE PATIENT RECORDS General Provisions § 2.14 Minor patients. (a) Definition of minor... or drug abuse treatment, any written consent for disclosure authorized under subpart C of these... drug abuse treatment, any written consent for disclosure authorized under subpart C of these...

42 CFR 2.14 - Minor patients.

Code of Federal Regulations, 2011 CFR

2011-10-01

... ALCOHOL AND DRUG ABUSE PATIENT RECORDS General Provisions § 2.14 Minor patients. (a) Definition of minor... or drug abuse treatment, any written consent for disclosure authorized under subpart C of these... drug abuse treatment, any written consent for disclosure authorized under subpart C of these...

42 CFR 2.14 - Minor patients.

Code of Federal Regulations, 2010 CFR

2010-10-01

... ALCOHOL AND DRUG ABUSE PATIENT RECORDS General Provisions § 2.14 Minor patients. (a) Definition of minor... or drug abuse treatment, any written consent for disclosure authorized under subpart C of these... drug abuse treatment, any written consent for disclosure authorized under subpart C of these...

42 CFR 2.14 - Minor patients.

Code of Federal Regulations, 2013 CFR

2013-10-01

... ALCOHOL AND DRUG ABUSE PATIENT RECORDS General Provisions § 2.14 Minor patients. (a) Definition of minor... or drug abuse treatment, any written consent for disclosure authorized under subpart C of these... drug abuse treatment, any written consent for disclosure authorized under subpart C of these...

42 CFR 2.14 - Minor patients.

Code of Federal Regulations, 2014 CFR

2014-10-01

... ALCOHOL AND DRUG ABUSE PATIENT RECORDS General Provisions § 2.14 Minor patients. (a) Definition of minor... or drug abuse treatment, any written consent for disclosure authorized under subpart C of these... drug abuse treatment, any written consent for disclosure authorized under subpart C of these...

[Linguistic minorities in Canada and health].

PubMed

Bouchard, Louise; Desmeules, Martin

2013-10-01

Official language minorities (Francophones outside of Quebec and Anglophones in Quebec) make up about 6.4% of the Canadian population. Even though the Canadian constitution gives legal equality status to French and English, there is still room to ask if this equality is maintained in the health sector. In other words, do Francophone and Anglophone communities of Canada have the same health profiles regardless of their minority or majority status? Do they have access to the same health services and in the same conditions? The objective of this paper is to identify the health issues associated with belonging to a linguistic minority. Our research allows us to highlight the social and health disparities that can be attributed to belonging to a minority. In the Canadian context, which has two official languages, an equitable health policy will have to take into consideration language as a determinant of health. Copyright © 2013 Longwoods Publishing.

7 CFR 1753.4 - Major and minor construction.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 11 2011-01-01 2011-01-01 false Major and minor construction. 1753.4 Section 1753.4... AGRICULTURE TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES General § 1753.4 Major and minor... H (OMB control number 0572-0062). The requirements and procedures for minor construction are...

7 CFR 1753.4 - Major and minor construction.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 11 2010-01-01 2010-01-01 false Major and minor construction. 1753.4 Section 1753.4... AGRICULTURE TELECOMMUNICATIONS SYSTEM CONSTRUCTION POLICIES AND PROCEDURES General § 1753.4 Major and minor... H (OMB control number 0572-0062). The requirements and procedures for minor construction are...

Office management of minor wounds.

PubMed Central

Gouin, S.; Patel, H.

2001-01-01

OBJECTIVE: To review office interventions for minor wounds not requiring sutures, such as abrasions, bites, and lacerations. QUALITY OF EVIDENCE: Most information on minor wound management comes from descriptive studies. Few comparative studies examine the effectiveness of topical antisepsis for minor wounds. Several clinical trials have demonstrated that tissue adhesives produce short- and long-term cosmetic results equivalent to those achieved with suture materials. MAIN MESSAGE: Sterile saline is the least toxic solution for wound irrigation. Chlorhexidine (2%) and povidone iodine (10%) have been the most investigated antiseptic solutions. Systemic antibiotics are unnecessary for wounds unlikely to be infected. All bite wounds require special attention. Primary closure of bite wounds is indicated in certain circumstances: less than 12-hour-old nonpuncture wounds, uninfected wounds, and low-risk lesions (such as on the face). In spite of their many advantages, skin tapes should be used for low-tension wounds only. The popularity of tissue adhesives has greatly increased. Since the advent of newer products (with increased bonding strength and flexibility), adhesives are used to manage most lacerations except those in areas of high tension (e.g., joints) and on mucosal surfaces. CONCLUSION: Minor wounds not requiring sutures can be managed easily in the office. PMID:11340758

The Ethnic Minority Educator: Near Extinction?

ERIC Educational Resources Information Center

Chinn, Philip C.

1988-01-01

This article briefly describes the decline of the number of minority teachers at a time when the numbers of minority students are increasing and are projected to increase through the end of this century. The article reports a variety of studies and statistics which reflect this trend. (JL)

Minority Teacher Recruitment and Retention Strategies

ERIC Educational Resources Information Center

Kearney-Gissendaner, Janet E.

2010-01-01

The tools and resources in this book help school leaders seamlessly incorporate minority teacher recruitment and retention programs into current human-resources activities. With details about exemplary minority teacher recruitment and retention programs, this book also showcases strategies for how to replicate such programs in your own school or…

7 CFR 772.7 - Leasing minor program loan security.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false Leasing minor program loan security. 772.7 Section 772..., DEPARTMENT OF AGRICULTURE SPECIAL PROGRAMS SERVICING MINOR PROGRAM LOANS § 772.7 Leasing minor program loan... property for Minor Program loans to a third party when: (1) Leasing is the only feasible way to continue to...

7 CFR 772.7 - Leasing minor program loan security.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 7 2011-01-01 2011-01-01 false Leasing minor program loan security. 772.7 Section 772..., DEPARTMENT OF AGRICULTURE SPECIAL PROGRAMS SERVICING MINOR PROGRAM LOANS § 772.7 Leasing minor program loan... property for Minor Program loans to a third party when: (1) Leasing is the only feasible way to continue to...

40 CFR 144.41 - Minor modifications of permits.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Minor modifications of permits. 144.41... (CONTINUED) UNDERGROUND INJECTION CONTROL PROGRAM Authorization by Permit § 144.41 Minor modifications of... part 124. Any permit modification not processed as a minor modification under this section must be made...

Influence of elliptical structure on impinging-jet-array heat transfer performances

NASA Astrophysics Data System (ADS)

Arjocu, Simona C.; Liburdy, James A.

1997-11-01

A three-by-three square array of submerged, elliptic, impinging jets in water was used to study the heat transfer distribution in the cooling process of a constant heat flux surface. Tow jet aspect ratios were used, 2 and 3, both with the same hydraulic diameter. The array was tested at Reynolds numbers from 300 to 1500 and impinging distances of 1 to 5 hydraulic diameters. Thermochromic liquid crystals wee used to map the local heat transfer coefficient using a transient method, while the jet temperature was kept constant. The liquid crystal images were recorded through an optical fiber coupled with a CCD camera and a frame grabber and analyzed based on an RGB-temperature calibration technique. The results are reported relative to the unit cell that is used to delimitate the central jet. The heat transfer variation is shown to depend on the impingement distance and Reynolds number. The elliptic jets exhibit axis switching, jet column instability and jet swaying. All of these mechanisms affect the enhancement of the heat transfer rate and its distribution. The results are compared in terms of average and local heat transfer coefficients, for both major and minor planes for the two jet aspect ratios.

Celestial Reference Frames at Multiple Radio Wavelengths

NASA Technical Reports Server (NTRS)

Jacobs, Christopher S.

2012-01-01

In 1997 the IAU adopted the International Celestial Reference Frame (ICRF) built from S/X VLBI data. In response to IAU resolutions encouraging the extension of the ICRF to additional frequency bands, VLBI frames have been made at 24, 32, and 43 gigahertz. Meanwhile, the 8.4 gigahertz work has been greatly improved with the 2009 release of the ICRF-2. This paper discusses the motivations for extending the ICRF to these higher radio bands. Results to date will be summarized including evidence that the high frequency frames are rapidly approaching the accuracy of the 8.4 gigahertz ICRF-2. We discuss current limiting errors and prospects for the future accuracy of radio reference frames. We note that comparison of multiple radio frames is characterizing the frequency dependent systematic noise floor from extended source morphology and core shift. Finally, given Gaia's potential for high accuracy optical astrometry, we have simulated the precision of a radio-optical frame tie to be approximately10-15 microarcseconds ((1-sigma) (1-standard deviation), per component).

The effect of heat sinks in GTA microwelding

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

Knorovsky, G.A.; Burchett, S.N.

1989-01-01

When miniature devices containing glass-to-metal seals are closure welded it is accepted practice to incorporate thermal heat sinks into the fixturing. This is intended to assure that the heat from gas tungsten arc (GTA) welding will not cause thermal stress-induced cracking of the seals and loss of hermeticity. The design of these heat sinks has never been systematically studied; instead only ''engineering horse sense'' has been applied. This practice has been successful in the past; however, the component being GTA welded have become smaller and more complex (i.e., more pins) and glass cracking problems are being encountered. The technology ofmore » producing glass seal-containing lids (called ''headers'') has benefited from finite element analyses in deciding how to optimally dimension pin-to-glass seal diameter ratios and glass-to-metal thickness ratios in order to minimize thermal stresses locked in during manufacture. It appeared likely that an analysts of the stresses generated by welding would also be beneficial. Recently, computer speed and code capabilities have increased to the point where finite element analysis of a close simulation of real hardware can be made, including the effect of external heat sinks. The work reported here involves an analysis (with some supporting experimental data) of a miniature thermal battery which encountered glass cracking problems. In the course of the analysis various heat sink practices were examined. Among other findings, through-thickness thermal gradients in a header with a heat sink were found to equal in-plane thermal gradients in a header without any heat sinking at the glass seal positions. Also noted were significant variations due to relatively minor changes in the weld preparation geometry. A summary of good practice for heat sinking will be presented. 4 refs., 6 figs., 2 tabs.« less

The magnetic-nanofluid heat pipe with superior thermal properties through magnetic enhancement

PubMed Central

2012-01-01

This study developed a magnetic-nanofluid (MNF) heat pipe (MNFHP) with magnetically enhanced thermal properties. Its main characteristic was additional porous iron nozzle in the evaporator and the condenser to form a unique flowing pattern of MNF slug and vapor, and to magnetically shield the magnet attraction on MNF flowing. The results showed that an optimal thermal conductivity exists in the applied field of 200 Oe. Furthermore, the minor thermal performance of MNF at the condenser limited the thermal conductivity of the entire MNFHP, which was 1.6 times greater than that filled with water for the input power of 60 W. The feasibilities of an MNFHP with the magnetically enhanced heat transfer and the ability of vertical operation were proved for both a promising heat-dissipation device and the energy architecture integrated with an additional energy system. PMID:22716909

40 CFR 158.60 - Minor use data policies.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Minor use data policies. 158.60... DATA REQUIREMENTS FOR PESTICIDES General Provisions § 158.60 Minor use data policies. FIFRA sec. 2(ll... addition, EPA has established policies with respect to minor uses of pesticides, including, but not limited...

Counseling Approaches for Enhancing Self-Esteem of Minorities.

ERIC Educational Resources Information Center

Singleton, Dorothy Kim

This monograph suggests various counseling techniques for enhancing the self-esteem of minorities. A frame of reference is presented for considering minority group self-esteem. Themes related to minority group perspectives and their existence in the writings of psychotherapists are reviewed. A section on cultural diversity discusses the family,…

7 CFR 784.10 - Estates, trusts, and minors.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 7 2011-01-01 2011-01-01 false Estates, trusts, and minors. 784.10 Section 784.10..., and minors. (a) Program documents executed by persons legally authorized to represent estates or.... (b) A minor who is otherwise eligible for assistance under this part must, also: (1) Establish that...

40 CFR 122.63 - Minor modifications of permits.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 22 2011-07-01 2011-07-01 false Minor modifications of permits. 122.63..., Revocation and Reissuance, and Termination of Permits § 122.63 Minor modifications of permits. Upon the.... Any permit modification not processed as a minor modification under this section must be made for...

7 CFR 1430.221 - Estates, trusts, and minors.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 10 2011-01-01 2011-01-01 false Estates, trusts, and minors. 1430.221 Section 1430... Program § 1430.221 Estates, trusts, and minors. (a) Program documents executed by producers legally... authority to execute such documents. (b) A minor who is otherwise eligible for assistance under this part...

The Impact of Financial Aid on Ethnic Minorities.

ERIC Educational Resources Information Center

Stampen, Jacob O.; Fenske, Robert H.

1988-01-01

"Great society" financial aid programs successfully raised the curve of minority participation, but in the late 1970s, the curve flattened and is descending as college costs outpace financial aid. The most promising strategy for overcoming declining minority participation is to improve academic performance among low-income and minority students.…

38 CFR 10.51 - Payments to minor child.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Payments to minor child. 10.51 Section 10.51 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUSTED COMPENSATION Payments § 10.51 Payments to minor child. Payments to minor child through legal guardian, natural...

38 CFR 10.51 - Payments to minor child.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Payments to minor child. 10.51 Section 10.51 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUSTED COMPENSATION Payments § 10.51 Payments to minor child. Payments to minor child through legal guardian, natural...

38 CFR 10.51 - Payments to minor child.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Payments to minor child. 10.51 Section 10.51 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUSTED COMPENSATION Payments § 10.51 Payments to minor child. Payments to minor child through legal guardian, natural...

38 CFR 10.51 - Payments to minor child.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Payments to minor child. 10.51 Section 10.51 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUSTED COMPENSATION Payments § 10.51 Payments to minor child. Payments to minor child through legal guardian, natural...

38 CFR 10.51 - Payments to minor child.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Payments to minor child. 10.51 Section 10.51 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUSTED COMPENSATION Payments § 10.51 Payments to minor child. Payments to minor child through legal guardian, natural...

Teaching minority children hygiene: investigating hygiene education in kindergartens and homes of ethnic minority children in northern Vietnam.

PubMed

Rheinländer, Thilde; Samuelsen, Helle; Dalsgaard, Anders; Konradsen, Flemming

2015-01-01

Ethnic minority children in Vietnam experience high levels of hygiene- and sanitation-related diseases. Improving hygiene for minority children is therefore vital for improving child health. The study objective was to investigate how kindergarten and home environments influence the learning of hygiene of pre-school ethnic minority children in rural Vietnam. Eight months of ethnographic field studies were conducted among four ethnic minority groups living in highland and lowland communities in northern Vietnam. Data included participant observation in four kindergartens and 20 homes of pre-school children, together with 67 semi-structured interviews with caregivers and five kindergarten staff. Thematic analysis was applied and concepts of social learning provided inputs to the analysis. This study showed that poor living conditions with lack of basic sanitation infrastructures were important barriers for the implementation of safe home child hygiene. Furthermore, the everyday life of highland villages, with parents working away from the households resulted in little daily adult supervision of safe child hygiene practices. While kindergartens were identified as potentially important institutions for improving child hygiene education, essential and well-functioning hygiene infrastructures were lacking. Also, hygiene teaching relied on theoretical and non-practice-based learning styles, which did not facilitate hygiene behaviour change in small children. Minority children were further disadvantaged as teaching was only provided in non-minority language. Kindergartens can be important institutions for the promotion of safe hygiene practices among children, but they must invest in the maintenance of hygiene and sanitation infrastructures and adopt a strong practice-based teaching approach in daily work and in teacher's education. To support highland minority children in particular, teaching styles must take local living conditions and caregiver structures into account

Minority Outlook: Opening the Door in Biomedicine.

ERIC Educational Resources Information Center

Freiherr, Gregory

1979-01-01

The national Minority Biomedical Support (MBS) Program, established in 1972 with National Institutes of Health funds, is described with emphasis on its role in increasing minority representation in biomedical research. (LBH)

25 CFR 213.12 - Leases executed by guardians of minors.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 25 Indians 1 2011-04-01 2011-04-01 false Leases executed by guardians of minors. 213.12 Section... Leases executed by guardians of minors. Leases executed by guardians of minors under order of court for a period extending beyond the minority of the minor will be approved unless it appears that such action...

25 CFR 213.12 - Leases executed by guardians of minors.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Leases executed by guardians of minors. 213.12 Section... Leases executed by guardians of minors. Leases executed by guardians of minors under order of court for a period extending beyond the minority of the minor will be approved unless it appears that such action...

Minors and informed consent: a comparative approach.

PubMed

Stultiëns, Loes; Goffin, Tom; Borry, Pascal; Dierickx, Kris; Nys, Herman

2007-04-01

The European Convention on Human Rights and Biomedicine of the Council of Europe provides in article 6 for special protection of persons who are not able to give free and informed consent to an intervention in the health field, e.g. minors. According to the second paragraph of this article it is up to domestic law to decide whether and under which conditions a minor is capable of taking autonomous decisions in the health field. In the present article an overview is given of the legal regulations in place regarding the position of minors in a health care setting in the EU Member States that have ratified the European Convention on Human Rights and Biomedicine namely Cyprus, Czech Republic, Denmark, Estonia, Greece, Hungary, Lithuania, Portugal, Slovakia, Slovenia and Spain. As the overview will show, the legal position of minor patients in a health care setting varies from country to country. This in view of the system they have opted for as well as the age and circumstances under which minors are allowed to take health care decisions autonomously.

Psychiatrists' views of compulsory psychiatric care of minors.

PubMed

Turunen, Suvi; Välimäki, Maritta; Kaltiala-Heino, Riittakerttu

2010-01-01

Commitment to psychiatric care is in Finland allowed for minors in broader terms than for adults. Minors can be committed to and detained in involuntary psychiatric treatment if they suffer from severe mental disorder and fulfil the additional commitment criteria defined in the Mental Health Act. Adults can be committed to involuntary psychiatric care only if they are mentally ill (=psychotic), and fulfil the additional criteria. Involuntary treatment of minors has been increasing steadily since the Mental Health Act was passed in 1991. This study was set up to find out whether the Finnish child and adolescent psychiatrists agree with the need for defining broader commitment criteria for minors, and why. Semi-structured, reflexive dyadic interviews were carried out with 44 psychiatrists working with children and adolescents. The data was analysed using qualitative and quantitative content analysis. The analysis showed that broader commitment criteria for minors were favoured referring to developmental needs related to childhood and adolescence, prevention of mental illnesses and inadequacy of descriptive diagnosis in childhood and adolescence. The commitment criteria were rather seen as too narrow for adults than as too broad for minors, and the medical rights of minors were preferred over self-determination. Copyright 2009 Elsevier Ltd. All rights reserved.

[Judicial framework for medical decision-making concerning minors].

PubMed

Sirvent, N; Bérard, E

2010-02-01

One aim of the law promulgated in France on March 4, 2002 concerning patients' rights and the quality of the health care system was to reconsider the bases of the physician-patient relationship. The new legal framework recommends establishment of a true dialogue between the two protagonists, and it assigns decisional priority to the patient rather than to the physician or third parties. In the case of minors, the principle of parental authority requires that the physician consults the holders of this authority before making any medical decision. However, the law of March 4, 2002 also reinforced the participation of minors in medical decisions concerning them. The lawmaker explicitly envisaged the possibility of overruling the principle of parental authority. This new "balance of power" obliges the physician to inform the minor of his or her medical condition in a manner appropriate to the child's degree of maturity. The minor may even put forward the principle of medical secrecy to prevent the sharing of information with his or her parents. This new "autonomy" of minors gives rise to at least two reservations: i) the difficulty involved in assessment of a minor's degree of discernment; ii) the minor's vulnerability with respect to his or her entourage. Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.

40 CFR 158.60 - Minor use data policies.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Minor use data policies. 158.60... DATA REQUIREMENTS FOR PESTICIDES General Provisions § 158.60 Minor use data policies. FIFRA sec. 2(ll... to, the following: (a) A new data requirement pertinent to both an unregistered minor use and a...

Learning Potential Tests for Ethnic Minorities.

ERIC Educational Resources Information Center

Hamers, J. H. M.; Pennings, A. H.

1995-01-01

This article presents the results of three studies in the learning-potential testing of children from minority groups: (1) Test of Children's Learning Ability; (2) Learning Efficiency Battery; and (3) Learning Potential Test for Ethnic Minorities. It concludes that, although the development of culture-free tests is impossible, it is possible to…

New Minority Teachers' Perceptions of Teaching.

ERIC Educational Resources Information Center

Stallworth, B. Joyce

This study was a follow-up investigation of five minority first-year teachers who were 1992 graduates of the Peabody Internship/Induction Teaching Program. The study was designed to examine the socialization of new minority group teachers. Structured interview protocols for the teachers and their principals were the primary means of data…

Minority Politics and Group-Differentiated Curricula at Minority-Serving Colleges

ERIC Educational Resources Information Center

Cole, Wade M.

2011-01-01

This paper analyzes whether ethnocentric curricula, defined as courses that focus exclusively on particular racial/ethnic groups, are more prevalent at minority-serving colleges than at mainstream institutions. Using original curricular data for a sample of tribal, Black, Hispanic, and mainstream colleges, the author found that ethnocentric…

Measurements of 100 'Critical' Minor Planets from NEAT Archive

NASA Astrophysics Data System (ADS)

Deshmukh, Shishir

2017-07-01

Uncertainties associated with the orbits of minor planets can be reduced by analyzing archival imagery as attempted in the current investigation. Archival images from NEAT and NASA’s Skymorph database were analyzed using standard software to identify the minor planets listed in the critical list. Findings of each minor planet were submitted to Minor Planet Center (MPC) to offer better orbital solutions.

[Surgical management of minor salivary gland tumors].

PubMed

Zhou, Liang; Chen, Xiaoling; Huang, Weiting; Li, Kelan; Zhang, Xiaotong; Wang, Wei

2007-11-01

To study the clinical features of minor salivary gland tumors and to discuss the treatment modalities for these tumors. Retrospective analysis of 54 cases with minor salivary gland tumor operated in our hospital from 1997 to 2004. Among 54 cases with minor salivary gland tumors in this series, 16 patients lost of follow up. Among the remaining 38 patients, 2 patients with nasal cavity adenoid cystic carcinoma died of tumor recurrence 2 and 3 years after the surgery respectively, one patient with laryngeal myoepithelial carcinoma died of tumor recurrence 3 years after the surgery and one patient with paranasal sinus mucoepidermoid carcinoma died of recurrence 17 months after the surgery. Two patients with paranasal sinus adenoid cystic carcinoma recurred after the primary surgery and were survived without tumor after salvage surgery. The other patients survived with no tumor recurrence. While different histopathology of minor salivary gland tumors were found in this group, malignant tumors were predominant, accounting for 81.4%. The choice of treatment for minor salivary gland tumors depends upon the location and the histopathology of the tumors. The treatment policy for benign tumors is simple tumor excision, while that for malignant tumors is surgery combined with pre- or post-operative radiation therapy. Complete surgical resection of tumor masses and tumor free margin is essential for successful treatment of malignant minor salivary gland tumors.

Sex Trafficking of Minors.

PubMed

Moore, Jessica L; Kaplan, Dana M; Barron, Christine E

2017-04-01

Sex trafficking is an increasingly recognized global health crisis affecting every country and region in the world. Domestic minor sex trafficking is a subset of commercial sexual exploitation of children, defined as engagement of minors (<18 years of age) in sexual acts for items of value (eg, food, shelter, drugs, money) involving children victimized within US borders. These involved youth are at risk for serious immediate and long-term physical and mental health consequences. Continued efforts are needed to improve preventive efforts, identification, screening, appropriate interventions, and subsequent resource provision for victimized and high-risk youth. Copyright © 2016 Elsevier Inc. All rights reserved.

Limited rights of minors in the Dutch healthcare.

PubMed

Brands, Wolter; Brands, Marieke; Brands-Bottema, Gea

2014-11-30

In many countries, if not all, the autonomy of minors is limited. Especially in countries with comprehensive legislation in the field of health law the (lack of) autonomy of minors may create challenges. These problems become more complex if the costs of treatment are not paid by the government or covered by insurance. Some challenges are: At what age is a minor able to decide about his health? As not every treatment is the same, how should the system take this into account? The Netherlands has a long history of very comprehensive health care legislation. This legislation includes a section about the treatment of minors that addresses the questions of the conditions in which the autonomy of minors is limited. Though this legislation is limited to the Netherlands other countries face the same challenges.

We Can Recruit Minorities Into The Geosciences

NASA Astrophysics Data System (ADS)

O'Connell, S.

2011-12-01

Despite the dismal numbers, efforts to recruit minorities into the geosciences are improving, thanks in part to NSF's "Opportunities for Enhancing Diversity in the Geosciences" (OEDG) initiative. At Wesleyan University, a small liberal arts college in Connecticut, we have significantly increased our recruitment of minority students. Twenty percent (four students) of the class of 2013 are African American. Most of the recruitment is done on an individual basis and working in conjunction with the "Dean for Diversity and Student Engagement" and courting minority students in introductory classes. The Dean for Diversity and Student Engagement is aware of our interest in increasing diversity and that we are able to hire minority students during the academic year and through the summer with OEDG funds. When she identifies minority students who might be interested in the geosciences, she refers them to faculty in the Earth and Environmental Sciences Department. Our faculty can provide employment, mentoring and a variety of geo-related experiences. Courting students in introductory courses can include inviting them to lunch or other activity, and attending sports, theater or dance events in which they are participating. Not all efforts result in new majors. Courses in ancillary sciences may be stumbling blocks and higher grades in less demanding courses have lured some students into other majors. Nevertheless, we now have a large enough cohort of minority students so that minority students from other majors visit their friends in our labs. A critical mass? Even a student, who chooses another major, may continue an interest in geoscience and through outreach efforts and discussions with younger family members, may provide a bridge that becomes a conduit for future students.

Minority Students and Faculty in Higher Music Education

ERIC Educational Resources Information Center

Clements, Allen

2009-01-01

This article offers a brief summary of the current minority situation in university and college music programs in the United States. Research in this area has concentrated to varying degrees on specific subsets of the minority population (e.g., African Americans, Hispanics, Native Americans, Asians) as well as on minorities in a more general…

NIH Minority Programs.

ERIC Educational Resources Information Center

National Institutes of Health (DHHS), Bethesda, MD.

This publication contains brief descriptions of National Institutes of Health programs for underrepresented minorities, including fellowships, programs for high school students, graduate research assistantships, postdoctoral training, and programs for college students. The publication provides a description of each program, eligibility…

At Risk--Language Minority Preschool Children.

ERIC Educational Resources Information Center

Stowe, Carol Ann

Language minority children (those whose primary language is other than English) are significantly more likely than their non-minority peers to live in poverty, thereby qualifying for federal Head Start and bilingual education programs. An examination of the policies in these programs focuses on their area of overlap. It begins with an overview of…

7 CFR 1400.101 - Minor children.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 10 2011-01-01 2011-01-01 false Minor children. 1400.101 Section 1400.101 Agriculture... SUBSEQUENT CROP, PROGRAM, OR FISCAL YEARS Payment Limitation § 1400.101 Minor children. (a) Except as provided in paragraph (b) of this section, payments received by a child under 18 years of age as of June 1...

7 CFR 1400.101 - Minor children.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 10 2012-01-01 2012-01-01 false Minor children. 1400.101 Section 1400.101 Agriculture... SUBSEQUENT CROP, PROGRAM, OR FISCAL YEARS Payment Limitation § 1400.101 Minor children. (a) Except as provided in paragraph (b) of this section, payments received by a child under 18 years of age as of June 1...

7 CFR 1400.101 - Minor children.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 10 2014-01-01 2014-01-01 false Minor children. 1400.101 Section 1400.101 Agriculture... SUBSEQUENT CROP, PROGRAM, OR FISCAL YEARS Payment Limitation § 1400.101 Minor children. (a) Except as provided in paragraph (b) of this section, payments received by a child under 18 years of age as of June 1...

7 CFR 1400.101 - Minor children.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 10 2010-01-01 2010-01-01 false Minor children. 1400.101 Section 1400.101 Agriculture... SUBSEQUENT CROP, PROGRAM, OR FISCAL YEARS Payment Limitation § 1400.101 Minor children. (a) Except as provided in paragraph (b) of this section, payments received by a child under 18 years of age as of April 1...

7 CFR 1400.101 - Minor children.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 10 2013-01-01 2013-01-01 false Minor children. 1400.101 Section 1400.101 Agriculture... SUBSEQUENT CROP, PROGRAM, OR FISCAL YEARS Payment Limitation § 1400.101 Minor children. (a) Except as provided in paragraph (b) of this section, payments received by a child under 18 years of age as of June 1...

Strategies employed by sexual minority adolescents to cope with minority stress.

PubMed

Goldbach, J T; Gibbs, J J

2015-09-01

Sexual minority adolescents (SMA) experience disparities in health and behavioral health outcomes, including high rates of depression, anxiety, self-harm, substance use, HIV risk behavior, suicidal ideation, and suicide attempts. These outcomes are commonly attributed to minority stress. Stress experiences are different for SMA than their adult counterparts. For example, disclosing their sexual orientation may be more likely to result in homelessness because these youth more often live with parents or other family members. Although stress in this population has been explored in previous research, very little is known about how SMA cope. Relying upon an adolescent coping model, this study examined the coping strategies, responses, and resources of SMA related to stress. Forty-eight racially and ethnically diverse SMA (age 14-19) were recruited for 90-minute tape-recorded interviews. The semi-structured interviews were guided by a life history calendar. Recordings were transcribed verbatim and entered into QSR NVivo. All transcripts were coded by two members of the research team and went through a consensus process. Forty-three unique coping statements emerged that fit with the Compas model of adolescent coping. SMA cope with minority stress in similar ways to heterosexual youth coping with general stress, but findings suggest that SMA may also use different kinds of coping resources. Although further research is needed, the present study identified a variety of ways SMA cope with stress and can inform future research on the development interventions.

Possible systematics in the VLBI catalogs as seen from Gaia

NASA Astrophysics Data System (ADS)

Liu, N.; Zhu, Z.; Liu, J.-C.

2018-01-01

Aims: In order to investigate the systematic errors in the very long baseline interferometry (VLBI) positions of extragalactic sources (quasars) and the global differences between Gaia and VLBI catalogs, we use the first data release of Gaia (Gaia DR1) quasar positions as the reference and study the positional offsets of the second realization of the International Celestial Reference Frame (ICRF2) and the Goddard VLBI solution 2016a (gsf2016a) catalogs. Methods: We select a sample of 1032 common sources among three catalogs and adopt two methods to represent the systematics: considering the differential orientation (offset) and declination bias; analyzing with the vector spherical harmonics (VSH) functions. Results: Between two VLBI catalogs and Gaia DR1, we find that: i) the estimated orientation is consistent with the alignment accuracy of Gaia DR1 to ICRF, of 0.1 mas, but the southern and northern hemispheres show opposite orientations; ii) the declination bias in the southern hemisphere between Gaia DR1 and ICRF2 is estimated to be +152 μas, much larger than that between Gaia DR1 and gsf2016a which is +34 μas. Between two VLBI catalogs, we find that: i) the rotation component shows that ICRF2 and gsf2016a are generally consistent within 30 μas; ii) the glide component and quadrupole component report two declination-dependent offsets: dipolar deformation of +50 μas along the Z-axis, and quadrupolar deformation of -50 μas that would induce a pattern of sin2δ. Conclusions: The significant declination bias between Gaia DR1 and ICRF2 catalogs reported in previous studies is possibly attributed to the systematic errors of ICRF2 in the southern hemisphere. The global differences between ICRF2 and gsf2016a catalogs imply that possible, mainly declination-dependent systematics exit in the VLBI positions and need further investigations in the future Gaia data release and the next generation of ICRF.

Language choice in a minority school

NASA Astrophysics Data System (ADS)

Byram, M. S.

1985-12-01

This article arises from fieldwork in a school of the German minority in South Jutland, Denmark. The minority exists as a result of frontier changes between Germany and Denmark, most recently in 1920. A referendum held in that year as a result of the Treaty of Versailles left a cultural and linguistic minority which, by today, has its own school system, politial party and cultural rights. The research was carried out using qualitative, ethnographic methods and the article focuses on one aspect, namely the issue of language use by bilingual pupils in one of the minority's schools. Pupils' choice of Danish or German in different situations within and outside schools was analyzed through the use of language diaries, informal interviews, and participant observation. The diary entries are analyzed and commented on in the light of interviews and observations. Pupils' awareness of their language use is not static but becomes dynamic as a consequence of being involved in research. The implications of this for educational policy are considered in the context of current developments in language education in British schools.

Ethnic minority psychology: struggles and triumphs.

PubMed

Sue, Stanley

2009-10-01

This article focuses on my interpretation of the history of ethnic minority psychology, using as a base the presentations of the contributing authors to this special issue of Cultural Diversity and Ethnic Minority Psychology. Because each contributing author has focused on a particular ethnic group or a particular aspect of history, my goal is to focus on 3 common issues and problems. First, what are the themes and issues that confronted African Americans, American Indians and Alaska Natives, Asian Americans, and Latinos? Second, what were characteristics of the ethnic leaders on whose shoulders we now stand? Third, what kinds of relationships existed between members of different ethnic minority groups? Copyright 2009 APA, all rights reserved.

Prevalence of dating violence among sexual minority youth: variation across gender, sexual minority identity and gender of sexual partners.

PubMed

Martin-Storey, Alexa

2015-01-01

Dating violence during adolescence negatively influences concurrent psychosocial functioning, and has been linked with an increased likelihood of later intimate partner violence. Identifying who is most vulnerable for this negative outcome can inform the development of intervention practices addressing this problem. The two goals of this study were to assess variations in the prevalence of dating violence across different measures of sexual minority status (e.g., sexual minority identity or same-sex sexual behavior), and to assess whether this association was mediated by bullying, the number of sexual partners, binge drinking or aggressive behaviors. These goals were assessed by employing the Massachusetts Youth Risk Behavior Survey (N = 12,984), a regionally representative sample of youth ages 14-18. In this sample, a total of 540 girls and 323 boys reported a non-heterosexual identity, and 429 girls and 230 boys reported having had one or more same-sex sexual partners. The results generally supported a higher prevalence of dating violence among sexual minority youth. This vulnerability varied considerably across gender, sexual minority identity and the gender of sexual partners, but generally persisted when accounting for the mediating variables. The findings support investigating dating violence as a mechanism in the disparities between sexual minority and heterosexual youth, and the importance of addressing sexual minority youth specifically in interventions targeting dating violence.

29 CFR 1911.5 - Minor changes in standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 7 2010-07-01 2010-07-01 false Minor changes in standards. 1911.5 Section 1911.5 Labor... STANDARDS § 1911.5 Minor changes in standards. Section 6(b), when construed in light of the rulemaking provisions of the Administrative Procedure Act (5 U.S.C. 553), is read as permitting the making of minor...

7 CFR 760.25 - Estates and trusts; minors.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 7 2011-01-01 2011-01-01 false Estates and trusts; minors. 760.25 Section 760.25... § 760.25 Estates and trusts; minors. (a) A receiver of an insolvent debtor's estate and the trustee of a... who is a minor shall be eligible for indemnity payments only if he meets one of the following...

29 CFR 1911.5 - Minor changes in standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 29 Labor 7 2011-07-01 2011-07-01 false Minor changes in standards. 1911.5 Section 1911.5 Labor... STANDARDS § 1911.5 Minor changes in standards. Section 6(b), when construed in light of the rulemaking provisions of the Administrative Procedure Act (5 U.S.C. 553), is read as permitting the making of minor...

7 CFR 400.306 - Spouses and minor children.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 6 2011-01-01 2011-01-01 false Spouses and minor children. 400.306 Section 400.306... Regulations for the 1991 and Succeeding Crop Years § 400.306 Spouses and minor children. (a) The spouse and minor children of an individual are considered to be the same as the individual for purposes of this...

7 CFR 400.306 - Spouses and minor children.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 6 2012-01-01 2012-01-01 false Spouses and minor children. 400.306 Section 400.306... Regulations for the 1991 and Succeeding Crop Years § 400.306 Spouses and minor children. (a) The spouse and minor children of an individual are considered to be the same as the individual for purposes of this...

7 CFR 400.306 - Spouses and minor children.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 6 2013-01-01 2013-01-01 false Spouses and minor children. 400.306 Section 400.306... Regulations for the 1991 and Succeeding Crop Years § 400.306 Spouses and minor children. (a) The spouse and minor children of an individual are considered to be the same as the individual for purposes of this...

7 CFR 400.306 - Spouses and minor children.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 6 2010-01-01 2010-01-01 false Spouses and minor children. 400.306 Section 400.306... Regulations for the 1991 and Succeeding Crop Years § 400.306 Spouses and minor children. (a) The spouse and minor children of an individual are considered to be the same as the individual for purposes of this...

7 CFR 400.306 - Spouses and minor children.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 6 2014-01-01 2014-01-01 false Spouses and minor children. 400.306 Section 400.306... Regulations for the 1991 and Succeeding Crop Years § 400.306 Spouses and minor children. (a) The spouse and minor children of an individual are considered to be the same as the individual for purposes of this...

Sexual Orientation Identity in Relation to Minority Stress and Mental Health in Sexual Minority Women.

PubMed

Puckett, Jae A; Surace, Francisco I; Levitt, Heidi M; Horne, Sharon G

2016-10-01

Research often erases the distinct experiences of bisexual and queer women through collapsing participants with lesbian or gay women. In addition, queer is often not included as a sexual orientation identity in research, therefore limiting the available information about how this group experiences minority stress. Given these limitations, we sought to compare groups, based on their sexual orientation identity, on experiences of minority stress and mental health to further understand between group differences that often go unaccounted for in research. Participants (N = 249; age range 19-77; M = 38.43, SD = 12.98) completed an online survey exploring experiences of minority stress and mental health. We found that the group most at risk for encountering minority stressors depended on the specific stressor being examined. Queer and gay or lesbian women encountered greater victimization, discrimination, and expectations of discrimination than bisexual women. However, bisexual women had higher levels of identity concealment and internalized heterosexism than gay, lesbian, or queer women. While queer women tended to have fewer proximal stressors, they were similar to bisexual women in terms of psychological distress, with both groups scoring higher than gay or lesbian women. These results highlight the need to examine between group differences in future research. The experiences of minority stress appear to complexly relate to psychological distress in varying ways for different groups of women, with bisexual and queer women having the highest rates of psychological distress although they vary in the types of stressors that they encounter. In addition, the experiences of queer women were divergent from those of gay, lesbian, or bisexual women across many of the stressors, indicating that there is a need to further recognize this distinct group of women in future research.

Role and Function of the Minority Administrator

ERIC Educational Resources Information Center

Clark, Joyce H.

1977-01-01

Examines the history of administrator selection in urban areas and delineates the role of the minority administrator today. Presented at the First Annual Conference on The Minorities' Right to Post-Secondary Education, October 18, 1974. (HMV)

Integrated software package STAMP for minor planets

NASA Technical Reports Server (NTRS)

Kochetova, O. M.; Shor, Viktor A.

1992-01-01

The integrated software package STAMP allowed for rapid and exact reproduction of the tables of the year-book 'Ephemerides of Minor Planets.' Additionally, STAMP solved the typical problems connected with the use of the year-book. STAMP is described. The year-book 'Ephemerides of Minor Planets' (EMP) is a publication used in many astronomical institutions around the world. It contains all the necessary information on the orbits of the numbered minor planets. Also, the astronomical coordinates are provided for each planet during its suitable observation period.

Associations of Timing of Sexual Orientation Developmental Milestones and Other Sexual Minority Stressors with Internalizing Mental Health Symptoms Among Sexual Minority Young Adults.

PubMed

Katz-Wise, Sabra L; Rosario, Margaret; Calzo, Jerel P; Scherer, Emily A; Sarda, Vishnudas; Austin, S Bryn

2017-07-01

Sexual minorities (mostly heterosexual, bisexual, lesbian/gay) are more likely than heterosexuals to have adverse mental health, which may be related to minority stress. We used longitudinal data from 1461 sexual minority women and men, aged 22-30 years, from Wave 2010 of the Growing Up Today Study, to examine associations between sexual minority stressors and mental health. We hypothesized that sexual minority stressors (earlier timing of sexual orientation developmental milestones categorized into early adolescence, middle adolescence, late adolescence/young adulthood; greater sexual orientation mobility; more bullying victimization) would be positively associated with mental health outcomes (depressive and anxious symptoms). Linear regression models stratified by gender and sexual orientation were fit via generalized estimating equations and controlled for age and race/ethnicity. Models were fit for each stressor predicting each mental health outcome. Reaching sexual minority milestones in early versus middle adolescence was associated with greater depressive and anxious symptoms among lesbians and gay men. Reaching sexual minority milestones in late adolescence/young adulthood versus middle adolescence was associated with greater depressive symptoms among lesbians, but fewer depressive and anxious symptoms among gay men. Greater sexual orientation mobility was associated with greater depressive symptoms among mostly heterosexual women. More bullying victimization was associated with greater depressive symptoms among bisexual women and with greater anxious symptoms among mostly heterosexual women. Sexual minority stressors are associated with adverse mental health among some sexual minority young adults. More research is needed to understand what may be protecting some subgroups from the mental health effects of sexual minority stressors.

Developing and Implementing a Data Base and Microcomputer Tracking System To Track and Serve Minority Students To Enhance Minority Recruitment and Retention.

ERIC Educational Resources Information Center

Mendoza, Jose

Brief descriptions are provided of several components of Glendale Community College's (GCC's) programs to ensure adequate links with the minority community and stimulate enrollments to achieve parity in enrollment proportions. Introductory sections offer a rationale for minority emphasis programs, define "minority," enumerate reasons for attending…

29 CFR 780.318 - Exemption for nonlocal minors.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 29 Labor 3 2011-07-01 2011-07-01 false Exemption for nonlocal minors. 780.318 Section 780.318... 13(a)(6) Statutory Provisions § 780.318 Exemption for nonlocal minors. (a) Section 13(a)(6)(D) of the..., only to minors 16 years of age or under who are not “local” in the sense that they are away from their...

Early adolescent music preferences and minor delinquency.

PubMed

Ter Bogt, Tom F M; Keijsers, Loes; Meeus, Wim H J

2013-02-01

To test Music Marker Theory (MMT) positing that early adolescents' preferences for nonmainstream types of popular music indicate concurrent and later minor delinquency. MMT was tested in a 4-year longitudinal study (n = 309). The results showed that early fans of different types of rock (eg, rock, heavy metal, gothic, punk), African American music (rhythm and blues, hip-hop), and electronic dance music (trance, techno/hardhouse) showed elevated minor delinquency concurrently and longitudinally. Preferring conventional pop (chart pop) or highbrow music (classic music, jazz), in contrast, was not related to or was negatively related to minor delinquency. Early music preferences emerged as more powerful indicators of later delinquency rather than early delinquency, indicating that music choice is a strong marker of later problem behavior. The mechanisms through which music preferences are linked to minor delinquency are discussed within the framework of MMT.

Multiple Ions Resonant Heating and Acceleration by Alfven/cyclotron Fluctuations in the Solar Wind

NASA Astrophysics Data System (ADS)

Xie, H.; Ofman, L.

2003-12-01

We study the interaction between protons, and multiple minor ions (O5+, He++) and a given cyclotron resonant spectra in coronal hole plasma. One-dimensional hybrid simulations are performed in initially homogeneous, collisionless, magnetized plasma with waves propagating parallel to the background magnetic field. The self-consistent hybrid simulations are used to study how multiple minor species may affect the resonance interaction between a spectrum of waves and the solar wind protons. The results of the simulations provide a clear picture of wave-particle interaction under various coronal conditions, which can explain 1) how multiple minor ions affect the resonant heating and the temperature anisotropy of the solar wind protons by a given wave spectrum; 2) how energy is distributed and transferred among waves and different ion species; 3) the growth and damping of different beam microinstability modes, including both inward and outward waves; 4) the formation of proton double-peak distribution in the solar wind.

Minor burns - aftercare

MedlinePlus

... Larger than 2 inches (5 cm) On the hand, foot, face, groin, buttocks, hip, knee, ankle, shoulder, elbow, or wrist First aid for Minor Burns First, calm and reassure the person who is burned. If clothing is not stuck to the burn, remove it. ...

The challenge of asthma in minority populations.

PubMed

Leong, Albin B; Ramsey, Clare D; Celedón, Juan C

2012-08-01

The burden and disparity of asthma in race/ethnic minorities present a significant challenge. In this review, we will evaluate data on asthma epidemiology in minorities, examine potential reasons for asthma disparities, and discuss strategies of intervention and culturally sensitive care.

48 CFR 14.405 - Minor informalities or irregularities in bids.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Minor informalities or... Minor informalities or irregularities in bids. A minor informality or irregularity is one that is merely... cure any deficiency resulting from a minor informality or irregularity in a bid or waive the deficiency...

48 CFR 14.405 - Minor informalities or irregularities in bids.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Minor informalities or... Minor informalities or irregularities in bids. A minor informality or irregularity is one that is merely... cure any deficiency resulting from a minor informality or irregularity in a bid or waive the deficiency...

The Research Administrator's Responsibility for Buying from Minority-Owned Companies.

ERIC Educational Resources Information Center

Shaffer, Lyle E.

1979-01-01

The author, the president of Amoco Venture Capital Company, a subsidiary of Standard Oil Company of Indiana designed to promote minority purchasing and finance minority enterprise, describes his program and the national program to promote minority enterprise. Ways that research administrators can develop minority sources for laboratory needs are…

Minority Student Retention.

ERIC Educational Resources Information Center

Henderson, James C.

1991-01-01

Discusses the community college's role in Native American education. Describes recruitment, counseling, assessment, remedial, and outreach programs developed by San Juan College to help minority students succeed, and specifically help Native Americans bridge the worlds of public school, reservation, and university. Identifies keys to the programs'…

Minor Illnesses, Temperament, and Toddler Social Functioning

ERIC Educational Resources Information Center

Kolak, Amy M.; Frey, Tara J.; Brown, Chloe A.; Vernon-Feagans, Lynne

2013-01-01

Research Findings: Minor illnesses, such as upper respiratory infections, stomachaches, and fevers, have been associated with children's decreased activity and increased irritability. This multi-method investigation of 110 day care-attending children examined whether experience with recurrent, minor illnesses and negative emotionality worked…

12 CFR 1207.20 - Office of Minority and Women Inclusion.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 12 Banks and Banking 10 2014-01-01 2014-01-01 false Office of Minority and Women Inclusion. 1207... MINORITY AND WOMEN INCLUSION Minority and Women Inclusion and Diversity at Regulated Entities and the Office of Finance § 1207.20 Office of Minority and Women Inclusion. (a) Establishment. Each regulated...

40 CFR 52.2184 - Operating permits for minor sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Operating permits for minor sources. 52.2184 Section 52.2184 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... permits for minor sources. Emission limitations and related provisions established in South Dakota minor...

40 CFR 52.2184 - Operating permits for minor sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Operating permits for minor sources. 52.2184 Section 52.2184 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... permits for minor sources. Emission limitations and related provisions established in South Dakota minor...

41 CFR 109-40.110-2 - Minority business enterprises.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Minority business enterprises. 109-40.110-2 Section 109-40.110-2 Public Contracts and Property Management Federal Property... Minority business enterprises. Minority business enterprises shall have the maximum practical opportunity...

41 CFR 109-40.110-2 - Minority business enterprises.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Minority business enterprises. 109-40.110-2 Section 109-40.110-2 Public Contracts and Property Management Federal Property... Minority business enterprises. Minority business enterprises shall have the maximum practical opportunity...

40 CFR 52.2184 - Operating permits for minor sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Operating permits for minor sources. 52.2184 Section 52.2184 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... permits for minor sources. Emission limitations and related provisions established in South Dakota minor...

40 CFR 52.2184 - Operating permits for minor sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Operating permits for minor sources. 52.2184 Section 52.2184 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... permits for minor sources. Emission limitations and related provisions established in South Dakota minor...

40 CFR 52.2184 - Operating permits for minor sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Operating permits for minor sources. 52.2184 Section 52.2184 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... permits for minor sources. Emission limitations and related provisions established in South Dakota minor...

41 CFR 109-40.110-2 - Minority business enterprises.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Minority business enterprises. 109-40.110-2 Section 109-40.110-2 Public Contracts and Property Management Federal Property... Minority business enterprises. Minority business enterprises shall have the maximum practical opportunity...

Variation in Subjective Aging by Sexual Minority Status.

PubMed

Barrett, Anne; Barbee, Harry

2017-06-01

The past few decades have seen increased scholarly attention to gay and lesbian individuals' aging experiences; however, few studies examine differences in subjective aging by sexual minority status. We identify four perspectives on the association between sexual minority status and subjective aging-double jeopardy, crisis competence, gender interactive, and limited salience perspectives. We examine each perspective's predictions using data from the first wave of Midlife in the United States (1995-1996; MIDUS). Ordinary least square regression models reveal strongest support for the limited salience perspective, suggesting that sexual minority status has weaker effects on subjective aging than do other social factors, such as age, health, and gender. However, some results provide support for the gender interactive perspective, positing that the effect of sexual minority status on subjective aging varies by gender. Our study provides an organizational framework of theoretical perspectives that can guide further examinations of variation in aging experiences by sexual minority status.

Numerical simulation of turbulent flow and heat transfer though sinusoidal ducts

NASA Astrophysics Data System (ADS)

Abroshan, Hamid

2018-02-01

Turbulent forced convection heat transfer in corrugated plate surfaces was studied by means of CFD. Flow through corrugated plates, which are sets of sinusoidal ducts, was analyzed for different inlet flow angles (0° to 50°), aspect ratios (0.1 to 10), Reynolds numbers (2000 to 40,000) and Prantdel numbers (0.7 to 5). Heat transfer is affected significantly by variation of aspect ratio. A maximum heat transfer coefficient is observed at a particular aspect ratio although the aspect ratio has a minor effect on friction factor. Enlarging inlet flow angle also leads to a higher heat transfer coefficient and pressure loss in aspect ratios close to unity. Dependency of Nusselt and friction factor on the angle and aspect ratio was interpreted by means of appearance of secondary motions and coexistence of laminar and turbulent flow in a cross section. Comparing the results with experimental data shows a maximum 12.8% difference. By evaluating the results, some correlations were proposed to calculate Nusselt number and friction factor for entrance and fully developed regions. A corrugated plate with an aspect ratio equal to 1.125 and an inlet flow angle equal to 50° gives the best heat transfer and pressure drop characteristics.

25 CFR 115.401 - What is a minor's supervised account?

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false What is a minor's supervised account? 115.401 Section 115... TRIBES AND INDIVIDUAL INDIANS IIM Accounts: Minors § 115.401 What is a minor's supervised account? A minor's supervised account is a restricted IIM account from which all disbursements must be made...

25 CFR 115.419 - Who develops a minor's distribution plan?

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Who develops a minor's distribution plan? 115.419 Section... FOR TRIBES AND INDIVIDUAL INDIANS IIM Accounts: Minors § 115.419 Who develops a minor's distribution plan? A social service provider will develop a minor's distribution plan for approval by the BIA after...

25 CFR 115.419 - Who develops a minor's distribution plan?

Code of Federal Regulations, 2011 CFR

2011-04-01

... 25 Indians 1 2011-04-01 2011-04-01 false Who develops a minor's distribution plan? 115.419 Section... FOR TRIBES AND INDIVIDUAL INDIANS IIM Accounts: Minors § 115.419 Who develops a minor's distribution plan? A social service provider will develop a minor's distribution plan for approval by the BIA after...

25 CFR 115.401 - What is a minor's supervised account?

Code of Federal Regulations, 2011 CFR

2011-04-01

... 25 Indians 1 2011-04-01 2011-04-01 false What is a minor's supervised account? 115.401 Section 115... TRIBES AND INDIVIDUAL INDIANS IIM Accounts: Minors § 115.401 What is a minor's supervised account? A minor's supervised account is a restricted IIM account from which all disbursements must be made...

Recruitment of minority physicians into careers in internal medicine.

PubMed

Potts, J T

1992-06-15

Despite some initial success in the early 1970s, the important goal of increasing the numbers of underrepresented minorities in medical school and on medical faculties has stalled short of proportionate representation. To further the current efforts of the Association of Professors in Medicine (APM) and other national medical groups that are devoted to improving the numbers of minorities in medicine, ideas and program information must be shared among institutions. In this spirit, we review our experience at Massachusetts General Hospital. We found that the first step toward this goal must be an institutional commitment based on increased awareness and on special effort focused on housestaff recruitment. Once the numbers of minorities increase, the department chairperson, training program directors, and other involved faculty can work with younger minority physicians; the cooperative relationship thus created can guide the development of a strong minority recruitment program without requiring an undue time commitment from minority trainees and faculty. The APM has a combined goal: to achieve early practical results in individual departments, to play a catalytic role with the community and other national medical organizations, and to increase the number of minorities entering medical school and careers in medicine generally.

Retention of minority participants in clinical research studies.

PubMed

Keller, Colleen S; Gonzales, Adelita; Fleuriet, K Jill

2005-04-01

Recruitment of minority participants for clinical research studies has been the topic of several analytical works. Yet retention of participants, most notably minority and underserved populations, is less reported and understood, even though these populations have elevated health risks. This article describes two related, intervention-based formative research projects in which researchers used treatment theory to address issues of recruitment and retention of minority women participants in an exercise program to reduce obesity. Treatment theory incorporates a model of health promotion that allows investigators to identify and control sources of extraneous variables. The authors' research demonstrates that treatment theory can improve retention of minority women participants by considering critical inputs, mediating processes, and substantive participant characteristics in intervention design.

Britain's Ethnic Minorities.

ERIC Educational Resources Information Center

Central Office of Information, London (England).

This pamphlet discusses the situation of ethnic minorities--particularly those of Caribbean, Asian, or African origin--in the United Kingdom. Following introductory material, the background to immigration in Britain is described and the numbers and geographic distribution of the different ethnic groups are discussed. Next comes a general…

Minors' rights in medical decision making.

PubMed

Hickey, Kathryn

2007-01-01

In the past, minors were not considered legally capable of making medical decisions and were viewed as incompetent because of their age. The authority to consent or refuse treatment for a minor remained with a parent or guardian. This parental authority was derived from the constitutional right to privacy regarding family matters, common law rule, and a general presumption that parents or guardians will act in the best interest of their incompetent child. However, over the years, the courts have gradually recognized that children younger than 18 years who show maturity and competence deserve a voice in determining their course of medical treatment. This article will explore the rights and interests of minors, parents, and the state in medical decision making and will address implications for nursing administrators and leaders.

Acoustic streaming related to minor loss phenomenon in differentially heated elements of thermoacoustic devices

NASA Astrophysics Data System (ADS)

Mironov, Mikhail; Gusev, Vitalyi; Auregan, Yves; Lotton, Pierrick; Bruneau, Michel; Piatakov, Pavel

2002-08-01

It is demonstrated that the differentially heated stack, the heart of all thermoacoustic devices, provides a source of streaming additional to those associated with Reynolds stresses in quasi-unidirectional gas flow. This source of streaming is related to temperature-induced asymmetry in the generation of vortices and turbulence near the stack ends. The asymmetry of the hydrodynamic effects in an otherwise geometrically symmetric stack is due to the temperature difference between stack ends. The proposed mechanism of streaming excitation in annular thermoacoustic devices operates even in the absence of thermo-viscous interaction of sound waves with resonator walls. copyright 2002 Acoustical Society of America.

78 FR 72527 - Minority Enterprise Development Week, 2013

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-02

... fundamental promise. America's minority enterprises include everything from Main Street cornerstones that... to recover, our investments in minority owned and operated firms will help create jobs, strengthen...

Minority Student Success in College: What Works. Minority Student Success Project.

ERIC Educational Resources Information Center

Brewer, Carolyn

The Washington State Board for Community College Education and the Washington Center for Undergraduate Education undertook a national review of minority student success programs in 1990. Information was solicited from program directors, deans of instruction and student services, national organizations, state higher education boards, students,…