Science.gov

Sample records for line current spectrum

  1. IRIS Spectrum Line Plot

    NASA Video Gallery

    This video shows a line plot of the spectrum. The spectra here are shown for various locations on the Sun. The changes in the movie are caused by differing physical conditions in the locations. Cre...

  2. IRIS Spectrum Line Plot - Numeric Simulation

    NASA Video Gallery

    This video is similar to the IRIS Spectrum Line Plot video at http://www.youtube.com/watch?v=E4V_vF3qMSI, but now as derived from a numerical simulation of the Sun by the University of Oslo. Credit...

  3. Fraunhofer lines in the solar spectrum and immunodeficiency problems

    NASA Astrophysics Data System (ADS)

    Kondratyev, K. Ya.; Fedchenko, P. P.

    2004-05-01

    The importance of the presence of Fraunhofer lines in the solar spectrum for development of immunodeficiency has been demonstrated. In vitro and in vivo tests of illumination within Mg lines have proved the possibility to reduce the level of HIV/AIDS development.

  4. In-line beam current monitor

    NASA Astrophysics Data System (ADS)

    Ekdahl, C. A., Jr.; Frost, C. A.

    1984-11-01

    An intense relativistic electron beam current monitor for a gas neutralized beam transport line includes a first foil for conducting plasma current to the wall where it is measured as it traverses an inductive loop formed by a cavity in the wall. An insulator foil separates the first foil from a second conducting foil which returns the current to the plasma environment.

  5. In-line beam current monitor

    DOEpatents

    Ekdahl, Jr., Carl A.; Frost, Charles A.

    1986-01-01

    An intense relativistic electron beam current monitor for a gas neutralized beam transport line includes a first foil for conducting plasma current to the wall where it is measured as it traverses an inductive loop formed by a cavity in the wall. An insulator foil separates the first foil from a second conducting foil which returns the current to the plasma environment.

  6. In-line beam current monitor

    DOEpatents

    Ekdahl, C.A. Jr.; Frost, C.A.

    1984-11-13

    An intense relativistic electron beam current monitor for a gas neutralized beam transport line includes a first foil for conducting plasma current to the wall where it is measured as it traverses an inductive loop formed by a cavity in the wall. An insulator foil separates the first foil from a second conducting foil which returns the current to the plasma environment.

  7. The optical emission line spectrum of Mark 110

    NASA Astrophysics Data System (ADS)

    Véron-Cetty, M.-P.; Véron, P.; Joly, M.; Kollatschny, W.

    2007-11-01

    Aims:We analyse in detail the rich emission line spectrum of Mark 110 to determine the physical conditions in the nucleus of this object, a peculiar NLS1 without any detectable Fe II emission associated with the broad line region and with a λ5007/Hβ line ratio unusually large for a NLS1. Methods: We use 24 spectra obtained with the Marcario Low Resolution Spectrograph attached at the prime focus of the 9.2 m Hobby-Eberly telescope at the McDonald observatory. We fitted the spectrum by identifying all the emission lines (about 220) detected in the wavelength range 4200-6900 Å (at rest). Results: The narrow emission lines are probably produced in a region with a density gradient in the range 103-106 cm-3 with a rather high column density (5×1021 cm-2). In addition to a narrow line system, three major broad line systems with different line velocity and width are required. We confirm the absence of broad Fe II emission lines. We speculate that Mark 110 is in fact a BLS1 with relatively “narrow” broad lines but with a BH mass large enough compared to its luminosity to have a lower than Eddington luminosity. Based on observations obtained with the Hobby-Eberly Telescope, which is a joint project of the University of Texas at Austin, the Pennsylvania State University, Stanford University, Ludwig-Maximilians-Universität München, and Georg-August-Universität Göttingen. Table A.1 is only available in electronic form at http://www.aanda.org

  8. The interstellar absorption-line spectrum of Mu Ophiuchi

    NASA Technical Reports Server (NTRS)

    Cardelli, J.; Boehm-Vitense, E.

    1982-01-01

    UV interstellar lines have been measured on high-resolution, long- and short-wavelength IUE spectra of the B8 V star Mu Oph. Column densities for the observed atoms and ions have been determined as well as turbulent velocities. The interstellar spectrum of Mu Oph is similar to the ones for Rho Oph and Zeta Oph. The ionization equilibria of several elements give consistent limits for the electron density. The C I line arising from different fine-structure levels are studied to yield estimates on the physical conditions in the cloud. Relative depletion of elements in the cloud seen in the interstellar spectrum of Mu Oph follows the same pattern as seen in the interstellar spectra of Zeta Oph and six other stars in the Rho Oph cloud complex.

  9. H. cap alpha. line in the spectrum of HDE 245770

    SciTech Connect

    Voikhanskaya, N.F.

    1980-09-01

    Constant and variable components are discriminated in the profile of the H..cap alpha.. emission line in the spectrum of the star HDE 245770. The variable component is formed near the degenerate component of the binary system. The constant part of the line has a steady radial velocity of +10 km/sec, while the variable part exhibits a radial-velocity curve having the same period, 104 sec, as the pulsations of the corresponding variable x-ray source A0535+26.

  10. Infrared emission-line spectrum of Gamma Cassiopeiae

    SciTech Connect

    Hamann, F.; Simon, M.

    1987-07-01

    The near-IR spectrum of Gamma Cas contains emission lines of H I, He I, and Mg II. No lines of low-excitation species, such as are found in cool and dense environments, are detected. At the time of the observations,the observed Br-alpha and Br-gamma profiles were double-peaked, with V/R roughly 0.5 and FWHM roughly 260 km/s. The Br-gamma line profile varied significantly over the 4.5 month interval between the observations and those published by Chabaev and Maillard in 1985. The IR hydrogen line fluxes indicate that these lines are formed in a small, dense, optically thick region where the density of ionized gas declines sharply with distance from the star. Both the line profiles and fluxes are shown to be inconsistent with the predictions of standard stellar wind theory, but are in qualitative agreement with a rotating disk model such as was proposed in 1978 by Poeckert and Marlborough. The observations are discussed briefly in terms of their similarities and differences with the IR emission-line spectra of luminous young stellar objects. 40 references.

  11. The infrared emission-line spectrum of Gamma Cassiopeiae

    NASA Astrophysics Data System (ADS)

    Hamann, F.; Simon, M.

    1987-07-01

    The near-IR spectrum of Gamma Cas contains emission lines of H I, He I, and Mg II. No lines of low-excitation species, such as are found in cool and dense environments, are detected. At the time of the observations,the observed Br-alpha and Br-gamma profiles were double-peaked, with V/R roughly 0.5 and FWHM roughly 260 km/s. The Br-gamma line profile varied significantly over the 4.5 month interval between the observations and those published by Chabaev and Maillard in 1985. The IR hydrogen line fluxes indicate that these lines are formed in a small, dense, optically thick region where the density of ionized gas declines sharply with distance from the star. Both the line profiles and fluxes are shown to be inconsistent with the predictions of standard stellar wind theory, but are in qualitative agreement with a rotating disk model such as was proposed in 1978 by Poeckert and Marlborough. The observations are discussed briefly in terms of their similarities and differences with the IR emission-line spectra of luminous young stellar objects.

  12. Emission lines in the optical spectrum of 3 Cen A

    NASA Astrophysics Data System (ADS)

    Wahlgren, G. M.; Hubrig, S.

    2004-05-01

    Previously, weak emission lines had been detected at red wavelengths in the spectra of a limited sample of mid to late B type main sequence stars. A fuller description of the occurrence and origins of these lines has yet to be forwarded, in part due to the lack of observations detailing the spectral transitions involved. To address this deficiency, we present a line list of weak emission features found in the optical and near infrared spectral region of the chemically peculiar He-weak star 3 Cen A (HD 120709). Nearly 350 features, mostly associated with allowed transitions from high-excitation states of first ions, are catalogued along with identifications. Prominent among the emission lines are the spectra P II, Mn II, Fe II, Ni II and Cu II. Emission lines from Ca II, Si II and Hg II are also evident. Abundances are determined for several elements from synthetic spectrum fitting, with anomalies detected for the ions O I/II, P II/III and Si II/III. The LTE synthetic spectrum fitting also revealed that the low excitation 4s-4p transitions of Fe II predict an abundance that is greater than that determined from higher excitation 4d-4f transitions. Several of these latter transitions have upper energy levels that are found to be associated with emission lines. We also present empirical considerations for the excitation processes leading to the weak emission lines. Based on observations obtained at the European Southern Observatory, La Silla, Chile, No. 65.L-0316 and Paranal, Chile No. 266.D-5655. Tables 2 and 3 are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/418/1073

  13. Line Identifications in the Ultraviolet Spectrum of VV Cephei

    NASA Astrophysics Data System (ADS)

    Bauer, W. H.; Bennett, P. D.; Brown, A.

    2005-12-01

    VV Cephei is an eclipsing binary system consisting of an M2 Iab supergiant star with a substantial circumstellar wind, and a hot companion, probably an early B-type main sequence star. We observed the system with the STIS spectrograph on the Hubble Space Telescope during total eclipse, when the hot star's light was scattered by the extensive M supergiant wind. A rich emission-line spectrum was observed, with over two thousand emission features. A weak continuum is present during total eclipse, which strengthens markedly shortward of 1500 Å. Numerous circumstellar and interstellar absorption features are also present. We have used an on-line compilation of spectral lines to identify these features (Hirata and Horaguchi 1995, Vizier On-line Data Catalog, VI/69). We grouped lines with similar upper-level excitation potentials and examined the spectra to see if lines from those levels were observed, and down to what value of oscillator strength the lines were seen. Well over 90% of the emission features have plausible identifications using this procedure. The majority of the lines arise from singly ionized elements in the iron group with upper levels up to 14 eV. There are many blends in the spectra; roughly 5500 lines were selected from the database. Only about 400 features appear to be unblended. We present sample pages from an atlas in which we have annotated the emission lines and the circumstellar and interstellar absorption features with their identifications. This work was based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program GO-7269, and were supported by NASA through a grant from the Space Telescope Science Institute.

  14. Current transducers used in power line measurements

    NASA Astrophysics Data System (ADS)

    Milcarz, Sz.; Gołebiowski, J.

    2014-08-01

    There are many solutions used for current measurements in power lines. The study shows a transducer consisting of a ferromagnetic core, a beam placed in an air-gap and a sensor for optical readout. The beam is made of silicon with a thin 50%Ni50%Fe film. The material of the core is permalloy. A distribution of magnetic field depends on current supplying the power line. The beam is deflected due to magnetic field in the air-gap. A deflection of the beam is measured by the optical fibre sensor. Its advantage is simple design, high precision of processing, non-electric transmission, low costs and ability of a non-contact measurement. Comsol Multiphysics 4.4 and Magnetic Fields Module (mef) were used for modeling. An influence of magnetic circuit's materials and dimensions of the ferromagnetic core and the air-gap were tested in order to determine the most sufficient distribution of magnetic field in the air-gap. The study shows results of the modeling of the transducer compared to practical results for a similar construction scaled down to lower current values.

  15. Autism Spectrum Disorders: Neurobiology and Current Assessment Practices

    ERIC Educational Resources Information Center

    Allen, Ryan A.; Robins, Diana L.; Decker, Scott L.

    2008-01-01

    This study reviews recent research related to the neurobiology of Autism Spectrum Disorders (ASDs) an provides an empirical analysis of current assessment practices. Data were collected through a survey of 117 school psychologists. The Childhood Autism Rating Scale (CARS), Gilliam Autism Rating Scale (GARS), and Gilliam Asperger's Disorder Scale…

  16. Autism Spectrum Disorder: Examining Current Diagnosis Strategies and Assessment Tools

    ERIC Educational Resources Information Center

    Wormald, Amy Marie

    2011-01-01

    Recent literature notes a significant increase in students being diagnosed with Autism Spectrum Disorder (ASD). Yet, no uniform testing protocol exists. It is vital for students and educators that a unified testing process be created and established. This study investigated which ASD testing instruments were currently used in Southern California…

  17. X-Ray Spectrum of a Narrow-Line QSO

    NASA Technical Reports Server (NTRS)

    Halpern, Jules P.

    1998-01-01

    During the reporting period, seven papers using ASCA data, supported in whole or in part by this grant, were published or submitted to refereed journals. Their abstracts are given in this report, and the complete bibliographic references are listed in the Appendix. Titles include (1) A Broad-Band X-ray Study of the Geminga Pulsar; (2) ASCA Observations of PSR 1920+10 and PSR 0950+08; (3) X-ray and Optical Spectroscopy of IRAS 20181-2244: Not a Type 2 QSO, but a I Zw I Object; (4) Models for X-ray Emission from Isolated Pulsars; (5) Optical and X-ray Spectroscopy of 1E 0449.4-1823: Demise of the Original Type 2 QSO; (6) The ASCA Spectrum of the Broad-Line Radio Galaxy Pictor A: A Simple Power Law with No Fe Ka Line; and (7) ASCA Spectra of NGC 4388 and ESO 103-G35: Absorption, Reflection, and Variability in Intermediate Type Seyfert Galaxies.

  18. Detection of an unidentified emission line in the stacked X-ray spectrum of galaxy clusters

    SciTech Connect

    Bulbul, Esra; Foster, Adam; Smith, Randall K.; Randall, Scott W.; Markevitch, Maxim; Loewenstein, Michael

    2014-07-01

    We detect a weak unidentified emission line at E = (3.55-3.57) ± 0.03 keV in a stacked XMM-Newton spectrum of 73 galaxy clusters spanning a redshift range 0.01-0.35. When the full sample is divided into three subsamples (Perseus, Centaurus+Ophiuchus+Coma, and all others), the line is seen at >3σ statistical significance in all three independent MOS spectra and the PN 'all others' spectrum. It is also detected in the Chandra spectra of the Perseus Cluster. However, it is very weak and located within 50-110 eV of several known lines. The detection is at the limit of the current instrument capabilities. We argue that there should be no atomic transitions in thermal plasma at this energy. An intriguing possibility is the decay of sterile neutrino, a long-sought dark matter particle candidate. Assuming that all dark matter is in sterile neutrinos with m{sub s} = 2E = 7.1 keV, our detection corresponds to a neutrino decay rate consistent with previous upper limits. However, based on the cluster masses and distances, the line in Perseus is much brighter than expected in this model, significantly deviating from other subsamples. This appears to be because of an anomalously bright line at E = 3.62 keV in Perseus, which could be an Ar XVII dielectronic recombination line, although its emissivity would have to be 30 times the expected value and physically difficult to understand. Another alternative is the above anomaly in the Ar line combined with the nearby 3.51 keV K line also exceeding expectation by a factor of 10-20. Confirmation with Astro-H will be critical to determine the nature of this new line.

  19. Assessing Spectrum Compatibility for Beyond-Line-of-Sight UAS Control and Non-Payload Communications

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Wilson, Jeffrey D.; Bishop, William D.

    2014-01-01

    In order to provide for the safe integration of unmanned aircraft systems (UAS) into the National Airspace System (NAS), the control and non-payload communications (CNPC) link must be highly reliable. A specific requirement is that it must operate using aviation safety radiofrequency spectrum. Two types of links are required - line-of-sight (LOS) using terrestrial-based communications and beyond-line-of-sight (BLOS) using satellite communications. The 2012 World Radiocommunication Conference (WRC-12) provided a suitable allocation for LOS CNPC spectrum in the 5030 to 5091 MHz band which, when combined with a previously existing allocation fulfills the LOS spectrum requirement. The 5030 to 5091 MHz band is also allocated for BLOS CNPC, but since a significant portion of that band is required for LOS CNPC, additional BLOS spectrum is required. More critically, there are no satellites in operation or in development to provide such services in that band. Hence BLOS CNPC cannot be provided in protected aviation spectrum under current conditions. To fill this gap and enable integration of UAS into the NAS, it has been proposed to allow CNPC to operate over certain Fixed Satellite Service (FSS) bands in which many satellites currently provide commercial services. To enable this, changes in international regulation must be enacted. Agenda Item 1.5 of the 2015 WRC examines the possible regulatory changes needed. As part of the examination process, sharing between potential UAS using satellite communications for BLOS CNPC and other services allocated to the FSS bands being considered must be studied. This paper reviews the technical requirements and approach being undertaken for these sharing studies, with emphasis on study of interference from UAS into digital repeater links operating under the Fixed Service allocation. These studies are being conducted by NASA Glenn Research Center.

  20. Assessing Spectrum Compatibility for Beyond-Line-of-Sight UAS Control and Non-Payload Communications

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Wilson, Jeffrey D.; Bishop, William D.

    2014-01-01

    In order to provide for the safe integration of unmanned aircraft systems (UAS) into the National Airspace System (NAS), the control and non-payload communications (CNPC) link must be highly reliable. A specific requirement is that it must operate using aviation safety radiofrequency spectrum. Two types of links are required - line-of-sight (LOS) using terrestrial-based communications and beyond-line- of-sight (BLOS) using satellite communications. The 2012 World Radiocommunication Conference (WRC-12) provided a suitable allocation for LOS CNPC spectrum in the 5030-5091 MHz band which, when combined with a previously existing allocation fulfills the LOS spectrum requirement. The 5030- 5091 MHz band is also allocated for BLOS CNPC, but since a significant portion of that band is required for LOS CNPC, additional BLOS spectrum is required. More critically, there are no satellites in operation or in development to provide such services in that band. Hence BLOS CNPC cannot be provided in protected aviation spectrum under current conditions. To fill this gap and enable integration of UAS into the NAS, it has been proposed to allow CNPC to operate over certain Fixed Satellite Service (FSS) bands in which many satellites currently provide commercial services. To enable this, changes in international regulation must be enacted. Agenda Item 1.5 of the 2015 WRC examines the possible regulatory changes needed. As part of the examination process, sharing between potential UAS using satellite communications for BLOS CNPC and other services allocated to the FSS bands being considered must be studied. This paper reviews the technical requirements and approach being undertaken for these sharing studies, with emphasis on study of interference from UAS into digital repeater links operating under the Fixed Service allocation. These studies are being conducted by NASA Glenn Research Center.

  1. Correlation spectrum analyzer for direct measurement of device current noise

    NASA Astrophysics Data System (ADS)

    Ferrari, Giorgio; Sampietro, Marco

    2002-07-01

    This article analyzes the realization and the performance of a correlation spectrum analyzer specifically conceived to directly measure the current noise produced by electronic devices with maximum sensitivity. The text describes in detail and gives the design rules of the instrument input amplifiers taking into consideration noise, dynamic range, stability, and bandwidth, together with the effects that a device under test (DUT) having complex impedance introduce. This article shows that the proposed scheme may allow current noise measurements with a sensitivity improved by few orders of magnitude with respect to a standard spectrum analyzer and to a correlation analyzer in voltage scheme whenever the DUT has an impedance larger than few 10 kOmega. Such a sensitivity makes the proposed instrument ideal for the characterization of advanced devices, such as ultrashort channel metal-oxide-semiconductor field effect transistors, mesoscopic junctions, or spin dependent electron transfer devices where it may be necessary to detect noise levels as low as fA/RADICAL:[[RADICAND:[Hz

  2. Interstellar lines in the spectrum of supernova 1987a

    NASA Technical Reports Server (NTRS)

    Jenkins, Edward B.; Joseph, Charles L.

    1988-01-01

    The primary interest was to analyze the interstellar lines produced by gases along the line of sight which resides in the galactic plane and halo, as well as material in the Large Magellanic Cloud or the immediate environment of the supernovae. The ionization and fine-structure excitation of assorted atoms were intrepreted. The goal was to learn more about conditions in various regions of space and identify the probable origins for some velocity components whose locations were uncertain.

  3. Identification of Emission Lines in a Meteor Spectrum Obtained on August 2, 2011

    NASA Astrophysics Data System (ADS)

    Mozgova, A. M.; Borovicka, J.; Spurny, P.; Churyumov, K. I.

    125 emission lines were found in a meteor spectrum obtained on August 2, 2011. The identification of most of the lines is given. The following species were found in the spectrum: CrI, FeI, MgI, SiI, AlI, MnI, CaI, TiI, NaI, FeII, CaII, MgII, SiII, SrII.

  4. Spectrum line intensity as a surrogate for solar irradiance variations.

    PubMed

    Livingston, W C; Wallace, L; White, O R

    1988-06-24

    Active Cavity Radiometer Irradiance Monitor (ACRIM) solar constant measurements from 1980 to 1986 are compared with ground-based, irradiance spectrophotometry of selected Fraunhofer lines. Both data sets were identically sampled and smoothed with an 85-day running mean, and the ACRIM total solar irradiance (S) values were corrected for sunspot blocking (S(c)). The strength of the mid-photospheric manganese 539.4-nanometer line tracks almost perfectly with ACRIM S(e), Other spectral features formed high in the photosphere and chromosphere also track well. These comparisons independently confirm the variability in the ACRIM S(e), signal, indicate that the source of irradiance is faculae, and indicate that ACRIM S(e), follows the 11-year activity cycle. PMID:17842428

  5. Morphology and variability of helium line profiles in the P Cygni spectrum

    NASA Astrophysics Data System (ADS)

    Markova, N.

    1993-03-01

    Results are presented on a three-year study of the morphology and variability of 13 helium lines in the P Cygni optical spectrum. It was found that most lines in the P Cygni spectrum show profiles with a complicated structure: discrete components (with the most probable values for the velocity ranging from -140 to -180 km/s and from -200 to -220 km/s), which are superposed on a broader 'underlying' P Cygni profile. The central velocity of the helium discrete components is nearly the same for all lines in a given spectrum (sigma(v) = +/- 4 km/s). However, this velocity varies with time; the variations are qualitatively similar to those observed in other ions in the spectrum, e.g., HI (Markova, 1986, 1990), O II, Si III, and N II (Markova and Kolka, 1988), and Fe III (Lamers et al., 1985).

  6. Current Status of Research on Autism Spectrum Disorders and Offending

    ERIC Educational Resources Information Center

    Mouridsen, Svend Erik

    2012-01-01

    An emerging literature on autism spectrum disorders (ASD) and offending has highlighted that these disorders are at times associated with criminal behaviour. Ghaziuddin et al. (1991) reviewed the published literature on this topic from 1944 to 1990 and concluded that there was no clear link between Asperger syndrome (AS) and violent crime. They…

  7. Smoothed Temporal Variance Spectrum: weak line profile variations and NRP diagnostics

    NASA Astrophysics Data System (ADS)

    Kholtygin, A. F.; Sudnik, N. P.

    2016-05-01

    We describe the version of the Temporal Variance Spectrum (TVS, Fullerton, Gies & Bolton) method with pre-smoothed line profile (smoothed Temporal Variance Spectrum, smTVS). This method introduced by Kholtygin et al. can be used to detect the ultra weak variations of the line profile even for very noisy stellar spectra. We also describe how to estimate the mode of the non-radial pulsations (NRP) using the TVS and smTVS with different time spans. The influence of the rotational modulation of the line profile on the TVS is considered. The analysis of the contribution of NRP and rotational modulation in the global TVS is studied.

  8. [The current pathogen spectrum--what are we fighting against?].

    PubMed

    Scheithauer, S; Häfner, H; Lemmen, S W

    2012-01-01

    Surgical site infections are mainly caused by bacteria from the patients' skin or gut flora representing endogenous infections. In orthopedic and trauma surgery the skin commensals dominate and as a consequence Gram-positive bacteria are the main pathogens, particularly S. aureus. Additionally and especially in the case of foreign body infections, less virulent pathogens, e.g. coagulase-negative staphylococci play an important role. Due to newer microbiological techniques in detecting pathogens the spectrum of causative organisms is steadily increasing. As known for other nosocomial infections the relevance of multidrug resistant bacteria in surgical site infections is growing and the key player is methicillin-resistant S. aureus (MRSA); however vancomycin-resistant enterococci (VRE), extended spectrum betalactamases and/or carbapenemases producing enterobacteria and recently even panresistant Acinetobacter baumannii isolates have to be considered. PMID:22273700

  9. Field-Line Resonances in the Current Basis

    NASA Astrophysics Data System (ADS)

    Ostaszewski, Katharina; Glassmeier, Karl-Heinz; Nabert, Christian

    2016-04-01

    The MHD theory of the field-line resonance is of great importance for the understanding of ultra low-frequency waves in the magnetosphere. Most theoretical works concerning field-line resonance use the electric field as the basis set. In an ideal MHD plasma the field-aligned component of the electrical field vanishes because of the frozen-in theorem. However, a field-aligned current flows to maintain quasi-neutrality. This field-aligned current can only be carried by the transverse MHD Alfvèn wave and is therefore a characteristic feature of these types of waves. In this study we investigate the field-line resonance phenomenon using a three dimensional current vector space as the basis set. Using the model of the box magnetosphere of Southwood (1974) we derive an equation for the field-aligned current. This equation provides a simpler and more detailed insight into the coupling process between the fast mode and the Alfvèn mode. Furthermore we investigate the effect of the Hall current on the field-aligned current by including the Hall term in Ohm's law. It is shown that in some situations the Hall current can nullify the filed-aligned current and therefore prevent the resonance.

  10. Elimination of inrush current of transformers and distribution lines

    SciTech Connect

    Asghar, M.S.J.

    1995-12-31

    Repeated switching of distribution transformers take place due to poor generation and load shading. The transformer mounted on electric locomotive is also regularly reswitched after crossing each buffer zone between two substations. The steady-state magnetizing current of a transformer is about 5% of the full load current.But the transient inrush current may be as high as ten times the full-load current. The switching instant decides the nature and magnitude of the switching current and it is used here to control the inrush current. Another method is adopted by placing a capacitor at the secondary side of the unloaded transformer connected at the sending or receiving end of the distribution line. Third method is proposed using the distribution line as a low-pass filter. In case of a three-phase transformer, when it is switched, inrush current flows in either one or two phase windings. Instead of a simultaneous switching of all the phases (windings), each winding of transformer is switched at predetermined switching instants sequentially. Thus inrush currents are contained to steady-state level using an instant-controlled switching circuit. Switching of all phases completes within 1/3 or 1/4 of the power-cycle depending upon the mode of transformer configuration and the switching strategy. The switching current is found same as the steady-state no-load current. These schemes are useful for traction transformer as well as for poorly supplied and poorly maintained distribution lines including traction line which are subjected to repeated switching.

  11. X-Ray Spectrum of a Narrow Line Quasi-Stellar Object

    NASA Technical Reports Server (NTRS)

    Halpern, Jules P.

    1996-01-01

    This AO-3 observation of a new narrow-line QSO was motivated by our extensive study of the unclassified X-ray sources from the ROSAT/IRAS survey of Boller et al. IRAS 2018.1-2244 was observed to have Balmer lines and forbidden lines of roughly equal width. There are possibly weak broad wings on the H-alpha line. One of the questions to be addressed by hard X-ray spectroscopy is whether or not these wings are to be interpreted as scattered or weakly transmitted flux from a hidden broad-line region. The optical spectrum of this QSO also has very weak permitted Fe II lines, possibly indicative of a hidden broad line region. A new wrinkle on the concept of the narrow-line QSO is the gradual realization that luminous objects with very strong but narrow Fe II lines are showing up preferentially in soft X-ray surveys. The AO-1 objective was to detect the Geminga Pulsar and to interpret its 2-10 keV spectrum and pulse profile in terms of its X-ray emission spectra. Also, the AO-1 observed the Seyfert galaxy NGC 3516 to obtain a high signal-to-noise ratio spectrum. We expected NGC 3516 to be one of the best candidates for a successful demonstration of the details of the warm-absorber model.

  12. Parent population of flat-spectrum radio-loud narrow-line Seyfert 1 galaxies

    NASA Astrophysics Data System (ADS)

    Berton, M.; Foschini, L.; Ciroi, S.; Cracco, V.; La Mura, G.; Lister, M. L.; Mathur, S.; Peterson, B. M.; Richards, J. L.; Rafanelli, P.

    2015-06-01

    Flat-spectrum radio-loud narrow-line Seyfert 1 galaxies (NLS1s) are a recently discovered class of γ-ray emitting active galactic nuclei (AGN), that exhibit some blazar-like properties which are explained with the presence of a relativistic jet viewed at small angles. When blazars are observed at larger angles they appear as radio-galaxies, and we expect to observe an analogue parent population for beamed NLS1s. However, the number of known NLS1s with the jet viewed at large angles is not enough. Therefore, we tried to understand the origin of this deficit. Current hypotheses about the nature of parent sources are steep-spectrum radio-loud NLS1s, radio-quiet NLS1s and disk-hosted radio-galaxies. To test these hypotheses we built three samples of candidate sources plus a control sample, and calculated their black hole mass and Eddington ratio using their optical spectra. We then performed a Kolmogorov-Smirnov statistical test to investigate the compatibility of our different samples with a beamed population. Our results indicate that, when the inclination angle increases, a beamed source appears as a steep-spectrum radio-loud NLS1, or possibly even as a disk-hosted radio-galaxy with low black hole mass and high Eddington ratio. Further investigations, involving larger complete samples and observations at radio frequency, are needed to understand the incidence of disk-hosted radio-galaxies in the parent population, and to assess whether radio-quiet NLS1s can play a role, as well. Appendix A is available in electronic form at http://www.aanda.org

  13. A Spectrum of Support: Current and Best Practices for Students with Autism Spectrum Disorder (ASD) at Community Colleges

    ERIC Educational Resources Information Center

    Brown, Kirsten R.; Coomes, Michael D.

    2016-01-01

    More than 50% of all college students with a disability enroll in public 2-year institutions. Autism Spectrum Disorder (ASD) is a type of disability that affects a growing number of students in postsecondary education. Currently, over 70% of 2-year public institutions enroll students with ASD. In spite of increased awareness, the vast majority of…

  14. Electromagnetic response of buried cylindrical structures for line current excitation

    NASA Astrophysics Data System (ADS)

    Pajewski, Lara; Ponti, Cristina

    2013-04-01

    The Cylindrical-Wave Approach (CWA) rigorously solves, in the spectral domain, the electromagnetic forward scattering by a finite set of buried two-dimensional perfectly-conducting or dielectric objects [1]-[2]. In this technique, the field scattered by underground objects is represented in terms of a superposition of cylindrical waves. Use is made of the plane-wave spectrum [1] to take into account the interaction of such waves with the planar interface between air and soil, and between different layers eventually present in the ground [3]. Obstacles of general shape can be simulated through the CWA with good results, by using a suitable set of small circular-section cylinders [4]. Recently, we improved the CWA by facing the fundamental problem of losses in the ground [5]: this is of significant importance in remote-sensing applications, since real soils often have complex permittivity and conductivity, and sometimes also a complex permeability. While in previous works concerning the CWA a monochromatic or pulsed plane-wave incident field was considered, in the present work a different source of scattering is present: a cylindrical wave radiated by a line source. Such a source is more suitable to model the practical illumination field used in GPR surveys. The electric field radiated by the line current is expressed by means of a first-kind Hankel function of 0-th order. The theoretical solution to the scattering problem is developed for both dielectric and perfectly-conducting cylinders buried in a dielectric half-space. The approach is implemented in a Fortran code; an accurate numerical evaluation of the involved spectral integrals is performed, the highly-oscillating behavior of the homogeneous waves is correctly followed and evanescent contributions are taken into account. The electromagnetic field scattered in both air and ground can be obtained, in near- and far-field regions, for arbitrary radii and permittivity of the buried cylinders, as well as for

  15. Atomic and ionic spectrum lines below 2000A: hydrogen through argon

    SciTech Connect

    Kelly, R.L.

    1982-10-01

    A critical tabulation of observed spectral lines below 2000 angstroms has been prepared from the published literature up to July 1978. It is intended principally as an aid to those physicists and astronomers who deal with the spectra of highly stripped atoms. This report includes the first 18 elements, from hydrogen (including deuterium) through argon. The tabulation is divided into two main sections: the spectrum lines by spectrum, and a finding list. The entries for each element give the ionization species, ground state term, and ionization potential, as well as the best values of vacuum wavelength, intensity, and classification. A list of the pertinent references is appended at the end.

  16. The optically thick O III spectrum. I - Diagnostic ratios involving the intercombination lines

    NASA Technical Reports Server (NTRS)

    Kastner, S. O.; Bhatia, A. K.

    1989-01-01

    An escape-probability calculation of the optically thick O III spectrum is carried out to obtain the optical depth dependence of the intercombination doublet at 1663 A and of resonance lines between the 2p2, 2s2p3, and 2p4 configurations. The effect of optical depth on diagnostic ratios involving the intercombination lines is quantitatively established. The general question raised is whether such effects may occur in actual sources.

  17. Current Sheet Formation and Reconnection at a Magnetic X Line

    NASA Astrophysics Data System (ADS)

    DeVore, C. Richard; Antiochos, S. K.

    2011-05-01

    Phenomena ranging from the quiescent heating of the ambient plasma to the highly explosive release of energy and acceleration of particles in flares are conjectured to result from magnetic reconnection at electric current sheets in the Sun's corona. We are investigating numerically the formation and eventual reconnection of a current sheet in an initially potential 2D magnetic field containing a null. Subjecting this simple configuration to unequal stresses in the four quadrants bounded by the X-line separatrix distorts the potential null into a double-Y-line current sheet. Although the gas pressure is finite in our simulations, so that the plasma beta is infinite at the null, we find that even small distortions of the magnetic field induce the formation of a tangential discontinuity there. This result is well known to occur in the zero-beta, force-free limit; surprisingly, it persists into the high-beta regime where, in principle, a small plasma pressure inhomogeneity could balance all of the magnetic stress. In addition to working to understand the dynamical details of this ideal process, we are examining the effect of resistive dissipation on the development of the current sheet and are seeking to determine the critical condition for fast-reconnection onset in the sheet. Our progress on understanding these issues, and the implications for the dynamic activity associated with current sheets in the solar corona, will be reported at the conference. We gratefully acknowledge NASA sponsorship of our research.

  18. Surprises from a Deep ASCA Spectrum of the Broad Absorption Line Quasar PHL 5200

    NASA Technical Reports Server (NTRS)

    Mathur, Smita; Matt, G.; Green, P. J.; Elvis, M.; Singh, K. P.

    2002-01-01

    We present a deep (approx. 85 ks) ASCA observation of the prototype broad absorption line quasar (BALQSO) PHL 5200. This is the best X-ray spectrum of a BALQSO yet. We find the following: (1) The source is not intrinsically X-ray weak. (2) The line-of-sight absorption is very strong, with N(sub H) = 5 x 10(exp 23)/sq cm. (3) The absorber does not cover the source completely; the covering fraction is approx. 90%. This is consistent with the large optical polarization observed in this source, implying multiple lines of sight. The most surprising result of this observation is that (4) the spectrum of this BALQSO is not exactly similar to other radio-quiet quasars. The hard X-ray spectrum of PHL 5200 is steep, with the power-law spectral index alpha approx. 1.5. This is similar to the steepest hard X-ray slopes observed so far. At low redshifts, such steep slopes are observed in narrow-line Seyfert 1 (NLS1) galaxies, believed to be accreting at a high Eddington rate. This observation strengthens the analogy between BALQSOs and NLS1 galaxies and supports the hypothesis that BALQSOs represent an early evolutionary state of quasars. It is well accepted that the orientation to the line of sight determines the appearance of a quasar: age seems to play a significant role as well.

  19. Absorption-line profiles in a companion spectrum of a mass-losing cool supergiant

    NASA Technical Reports Server (NTRS)

    Rodrigues, Liliya L.; Boehm-Vitense, Erika

    1992-01-01

    Cool star winds can best be observed in resonance absorption lines seen in the spectrum of a hot companion, due to the wind passing in front of the blue star. We calculated absorption line profiles that would be seen in the ultraviolet part of the blue companion spectrum. Line profiles are derived for different radial dependences of the cool star wind and for different orbital phases of the binary. Bowen and Wilson find theoretically that stellar pulsations drive mass loss. We therefore apply our calculations to the Cepheid binary S Muscae which has a B5V companion. We find an upper limit for the Cepheid mass loss of M less than or equal to 7 x 10 (exp -10) solar mass per year provided that the stellar wind of the companion does not influence the Cepheid wind at large distances.

  20. Absorption line profiles in a companion spectrum of a mass losing cool supergiant

    NASA Technical Reports Server (NTRS)

    Rodrigues, Liliya L.; Boehm-Vitense, Erika

    1990-01-01

    Cool star winds can best be observed in resonance absorption lines seen in the spectrum of a hot companion, due to the wind passing in front of the blue star. We calculated absorption line profiles that would be seen in the ultraviolet part of the blue companion spectrum. Line profiles are derived for different radial dependences of the cool star wind and for different orbital phases of the binary. Bowen and Wilson find theoretically that stellar pulsations drive mass loss. We therefore apply our calculations to the Cepheid binary S Muscae which has a B5V companion. We find an upper limit for the Cepheid mass loss of M less than or equal to 7 x 10(exp -10) solar mass per year provided that the stellar wind of the companion does not influence the Cepheid wind at large distances.

  1. Irreversibility line in superconductor as line of constant shielding current density

    SciTech Connect

    Goemoery, F.; Takacs, S.; Holubar, T.

    1997-06-01

    The irreversibility of magnetic properties of superconductors is due to the existence of macroscopic shielding currents persisting for some period of time. The same currents offer nearly lossless electricity transport. Thus, the extent of magnetic irreversibility is directly proportional to the current-carrying capacity of a superconductor. Because the current-carrying capacity is an intrinsic property of the material, various experimental techniques should give the same irreversibility line corresponding to the same macroscopic shielding current density. Following this approach, the authors compared the irreversibility lines obtained from AC susceptibility measurement with those determined from quasistatic magnetization loops recorded with the help of a SQUID susceptometer. An additional parameter which has to be comparable is the electrical field characterizing the rate of change of the magnetic field. Fulfilling these conditions of equivalency, the authors found that it is possible to explain the irreversibility lines obtained by various techniques and at different conditions by the same physical model. They demonstrate that for the data, taken within two orders of magnitude for the current density and more than seven orders of magnitude for the electrical field, a consistent picture expressing all the observed features by the same model can be found. Measurements are presented from YBCO samples.

  2. A study of the P-Cygni lines in the ultraviolet spectrum of Beta Lyrae

    NASA Technical Reports Server (NTRS)

    Mazzali, Paolo A.

    1986-01-01

    The properties of the mass loss from the nondegenerate interacting binary system of beta Lyrae are investigated by analyzing the P-Cygni line profiles in the UV spectrum and considering these to be emitted in the wind outflow from the B8II primary component. Observed UV lines obtained by IUE are compared with theoretical models obtained using Sobolev's approximation. The models give satisfactory fittings. Simultaneous fitting of the resonance lines of Al II (1670 A) and Al III (1863 A) show that if the lines are emitted in the same region of the outflowing shell, as the line widths indicate, the electron temperature in the region is 23,500 K, and the mass loss is 2 times 10 to the minus 7th power solar masses/yr.

  3. Singularly continuous spectrum of a self-similar Laplacian on the half-line

    NASA Astrophysics Data System (ADS)

    Chen, Joe P.; Teplyaev, Alexander

    2016-05-01

    We investigate the spectrum of the self-similar Laplacian, which generates the so-called "pq random walk" on the integer half-line ℤ+. Using the method of spectral decimation, we prove that the spectral type of the Laplacian is singularly continuous whenever p ≠ /1 2 . This serves as a toy model for generating singularly continuous spectrum, which can be generalized to more complicated settings. We hope it will provide more insight into Fibonacci-type and other weakly self-similar models.

  4. Full wave effects on the lower hybrid wave spectrum and driven current profile in tokamak plasmas

    SciTech Connect

    Shiraiwa, S.; Ko, J.; Meneghini, O.; Parker, R.; Schmidt, A. E.; Greenwald, M.; Hubbard, A. E.; Hughes, J.; Ma, Y.; Podpaly, Y.; Rice, J. E.; Wallace, G.; Wolfe, S. M.; C-Mod Group, Alcator; Scott, S.; Wilson, J. R.

    2011-08-15

    A numerical modeling of current profile modification by lower hybrid current drive (LHCD) using a fullwave/Fokker-Planck simulation code is presented. A MHD stable LHCD discharge on Alcator C-Mod was analyzed, and the current profile from full wave simulations was found to show better agreement with the experiment than a ray-tracing code. Comparison of full wave and ray-tracing simulation shows that, although ray-tracing can reproduce the stochastic wave spectrum broadening, the full wave calculation predicts even wider spectrum broadening, and the wave spectrum fills all of the kinematically allowed domain. This is the first demonstration of LHCD current profile modeling using a full wave simulation code in a multi-pass absorption regime, showing the clear impact of full wave effects on the LHCD driven current profile.

  5. The Far-Infrared Emission Line and Continuum Spectrum of the Seyfert Galaxy NGC 1068

    NASA Technical Reports Server (NTRS)

    Spinoglio, Luigi; Smith, Howard A.; Gonzalez-Alfonso, Eduardo; Fisher, Jacqueline

    2005-01-01

    We report on the analysis of the first complete far-infrared spectrum (43-197 microns) of the Seyfert 2 galaxy NGC 1068 as observed with the Long Wavelength Spectrometer (LWS) onboard the Infrared Space Observatory (ISO). In addition to the 7 expected ionic fine structure emission lines, the OH rotational lines at 79, 119 and 163 microns were all detected in emission, which is unique among galaxies with full LWS spectra, where the 119 micron line, where detected, is always in absorption. The observed line intensities were modelled together with IS0 Short Wavelength Spectrometer (SWS) and optical and ultraviolet line intensities from the literature, considering two independent emission components: the AGN component and the starburst component in the circumnuclear ring of approximately 3kpc in size. Using the UV to mid-IR emission line spectrum to constrain the nuclear ionizing continuum, we have confirmed previous results: a canonical power-law ionizing spectrum is a poorer fit than one with a deep absorption trough, while the presence of a big blue bump is ruled out. Based on the instantaneous starburst age of 5 Myr constrained by the Br gamma equivalent width in the starburst ring, and starburst synthesis models of the mid- and far-infrared fine-structure line emission, a low ionization parameter (U=10(exp -3.5)) and low densities (n=100 cm (exp -3)) are derived. Combining the AGN and starburst components, we succeed in modeling the overall UV to far-IR atomic spectrum of SGC 1068, reproducing the line fluxes to within a factor 2.0 on average with a standard deviation of 1.4. The OH 119 micron emission indicates that the line is collisionally excited, and arises in a warm and dense region. The OH emission has been modeled using spherically symmetric, non-local, non-LTE radiative transfer models. The models indicate that the bulk of the emission arises from the nuclear region, although some extended contribution from the starburst is not ruled out. The OH abundance

  6. Profile, Current, and Halo Monitors of the PROSCAN Beam Lines

    SciTech Connect

    Doelling, Rudolf

    2004-11-10

    PROSCAN, an extended medical facility using proton beams for the treatment of deep-seated tumors and eye melanoma, is under construction at PSI. Ionization chambers and secondary emission monitors will be used as current monitors and in a multi-strip configuration as profile monitors at the PROSCAN beam lines. A thin and a thick version of these detectors are in preparation as well as a 4-segment ionization chamber to detect the beam halo. Electromagnetic and microphonic noise from the signal and high-voltage cables, saturation due to recombination, and the evaluation of the profiles are discussed, as well as measures to detect failures of the detectors during operation.

  7. Field aligned currents and the auroral spectrum below 1 keV

    NASA Technical Reports Server (NTRS)

    Arnoldy, R. L.

    1973-01-01

    Measurements during auroral events were conducted with the aid of detectors flown aboard three Nike-Tomahawk rocket flights. The detectors used to measure the auroral spectrum below 1 keV consisted of electrostatic analyzers positioned in the rocket to measure particles moving up and down the magnetic field lines. The analyzers measured electrons and protons simultaneously during a given sweep.

  8. Absorption lines in the spectrum of Q0248 + 4302 due to a foreground tidal tail

    SciTech Connect

    Sargent, W.L.W.; Steidel, C.C. California Univ., Berkeley )

    1990-08-01

    The strong absorption lines in the spectrum of the quasar Q0248 + 4302 are discussed. The absorption has been shown to be produced in a sinuous tidal tail which emanates from the nearby galaxy pair G0248 + 4302A,B. There is a velocity difference of about 260 km/s between the systemic redshift of the interacting galaxies and the redshift of the tidal tail at a galactocentric distance of about 11/h kpc. The large velocity spread observed in the tail gas is probably responsible for the unusual strength of the interstellar lines. 18 refs.

  9. An analysis of emission lines in the spectrum of P Cygni.

    NASA Astrophysics Data System (ADS)

    Markova, N.; de Groot, M.

    1997-10-01

    Using the coude spectrograph of the NAO 2m telescope at the Rhodope Mountains, Bulgaria, 9 spectra in the blue and 8 spectra in the red photographic region of P Cygni were obtained during 1990. By averaging the spectra in each set a S/N-ratio of about 45 was achieved. Comparing the lists of identifications published by Beals (1950PDAO....9....1B), de Groot (1969BAN....20..225D), Ozemre (1978PIstO.101....1O), Stahl et al. (1993A&AS...99..167S), Markova (1994A&AS..108..561M) and Markova & Zamanov (1995A&AS..114..499M), we conclude that the emission spectrum of P Cygni in our days is probably much richer and intensive than 60 years ago. A number of line parameters of the pure emission lines are measured. An estimate of the electron density and temperature in the region of [NII]-lines formation is obtained. Different velocity laws yielding similar density structures are discussed aiming to account for the results obtained on the basis of the [NII] lines. Possible mechanisms for the formation of the permitted pure emission-line spectrum are proposed.

  10. The FTS atomic spectrum tool (FAST) for rapid analysis of line spectra

    NASA Astrophysics Data System (ADS)

    Ruffoni, M. P.

    2013-07-01

    The FTS Atomic Spectrum Tool (FAST) is an interactive graphical program designed to simplify the analysis of atomic emission line spectra obtained from Fourier transform spectrometers. Calculated, predicted and/or known experimental line parameters are loaded alongside experimentally observed spectral line profiles for easy comparison between new experimental data and existing results. Many such line profiles, which could span numerous spectra, may be viewed simultaneously to help the user detect problems from line blending or self-absorption. Once the user has determined that their experimental line profile fits are good, a key feature of FAST is the ability to calculate atomic branching fractions, transition probabilities, and oscillator strengths-and their uncertainties-which is not provided by existing analysis packages. Program SummaryProgram title: FAST: The FTS Atomic Spectrum Tool Catalogue identifier: AEOW_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEOW_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public License version 3 No. of lines in distributed program, including test data, etc.: 293058 No. of bytes in distributed program, including test data, etc.: 13809509 Distribution format: tar.gz Programming language: C++. Computer: Intel x86-based systems. Operating system: Linux/Unix/Windows. RAM: 8 MB minimum. About 50-200 MB for a typical analysis. Classification: 2.2, 2.3, 21.2. Nature of problem: Visualisation of atomic line spectra including the comparison of theoretical line parameters with experimental atomic line profiles. Accurate intensity calibration of experimental spectra, and the determination of observed relative line intensities that are needed for calculating atomic branching fractions and oscillator strengths. Solution method: FAST is centred around a graphical interface, where a user may view sets of experimental line profiles and compare

  11. The nuclear region of low luminosity flat radio spectrum sources. II. Emission-line spectra

    NASA Astrophysics Data System (ADS)

    Gonçalves, A. C.; Serote Roos, M.

    2004-01-01

    We report on the spectroscopic study of 19 low luminosity Flat Radio Spectrum (LL FRS) sources selected from Marchã's et al. (\\cite{March96}) 200 mJy sample. In the optical, these objects are mainly dominated by the host galaxy starlight. After correcting the data for this effect, we obtain a new set of spectra clearly displaying weak emission lines; such features carry valuable information concerning the excitation mechanisms at work in the nuclear regions of LL FRS sources. We have used a special routine to model the spectra and assess the intensities and velocities of the emission lines; we have analyzed the results in terms of diagnostic diagrams. Our analysis shows that 79% of the studied objects harbour a Low Ionization Nuclear Emission-line Region (or LINER) whose contribution was swamped by the host galaxy starlight. The remaining objects display a higher ionization spectrum, more typical of Seyferts; due to the poor quality of the spectra, it was not possible to identify any possible large Balmer components. The fact that we observe a LINER-type spectrum in LL FRS sources supports the idea that some of these objects could be undergoing an ADAF phase; in addition, such a low ionization emission-line spectrum is in agreement with the black hole mass values and sub-Eddington accretion rates published for some FRS sources. Based on observations collected at the Multiple Mirror Telescope on Mt. Hopkins. Full Fig. 1 is only available in electronic form at http://www.edpsciences.org

  12. MIRO Observation of Comet C/2002 T7 (LINEAR) Water Line Spectrum

    NASA Technical Reports Server (NTRS)

    Lee, Seungwon; Frerking, Margaret; Hofstadter, Mark; Gulkis, Samuel; von Allmen, Paul; Crovisier, Jaques; Biver, Nicholas; Bockelee-Morvan, Dominique

    2011-01-01

    Comet C/2002 T7 (LINEAR) was observed with the Microwave Instrument for Rosetta Orbiter (MIRO) on April 30, 2004, between 5 hr and 16 hr UT. The comet was 0.63AU distance from the Sun and 0.68AU distance from the MIRO telescope at the time of the observations. The water line involving the two lowest rotational levels at 556.936 GHz is observed at 557.070 GHz due to a large Doppler frequency shift. The detected water line spectrum is interpreted using a non local thermal equilibrium (Non-LTE) molecular excitation and radiative transfer model. Several synthetic spectra are calculated with various coma profiles that are plausible for the comet at the time of observations. The coma profile is modeled with three characteristic parameters: outgassing rate, a constant expansion velocity, and a constant gas temperature. The model calculation result shows that for the distant line observation where contributions from a large coma space is averaged, the combination of the outgassing rate and the gas expansion velocity determines the line shape while the gas temperature has a negligible effect. The comparison between the calculated spectra and the MIRO measured spectrum suggests that the outgassing rate of the comet is about 2.0x1029 molecules/second and its gas expansion velocity about 1.2 km/s at the time of the observations.

  13. VizieR Online Data Catalog: 12C16O lines in Arcturus IR spectrum

    NASA Astrophysics Data System (ADS)

    Tsuji T.

    2009-06-01

    Based on the Infrared Atlas of the Arcturus Spectrum by Hinkle, Wallace, and Livingston (1995, Cat. ), we measured line-depth, full-width at half-maximum (FWHM), and equivalent width (EW) of 12C16O lines including fundamental, first and second overtone bands, and the results are given in table2. We used the electronic version of the ratioed spectra in our measurement and the tabulated results are measured raw data without any correction yet. The resulting data are used to investigate the nature of the infrared spectrum of Arcturus. It is found that only the weak lines (log(W/nu)<-4.75) can be analyzed consistently on the basis of the classical line-formation theory and hence can be used to extract the nature of the photosphere: We found logAC=7.97 (on the scale of log AH=12.00), micro and macro turbulent velocities to be 1.87 and 3.47km/s, respectively, for the photosphere. The nature of CO lines, however, shows abrupt change at about log(W/nu)=-4.75: The EWs of the lines larger than this limit can no longer be accounted for by the photospheric parameters determined from the weaker lines. A more simple demonstration of this fact is that the curves-of-growth of overtone as well as of fundamental CO lines show unpredictable upturn at about log(W/nu)=-4.75. Similar unusual behaviors of empirical curves-of-growth are found in other red giant and supergiant stars, and it looks as if the curves-of-growth are composite of at least two components of different origins. We think it difficult to understand such empirical data as due to the classical photosphere alone, and infrared spectra of cool luminous stars including Arcturus should be hybrid in nature. Although strong lines of the CO fundamentals show strengthening, the weaker lines show slight weakening, and we consider a possibility that these results are due to absorption/emission by the molecular clouds formed in the extended atmosphere. In cooler giant and supergiant stars in which CO lines show

  14. A search for the H2 /3, 0/ S1 line in the spectrum of Titan

    NASA Technical Reports Server (NTRS)

    Muench, G.; Trauger, J. T.; Roesler, F. L.

    1977-01-01

    Results are reported for measurements of the quadrupole S1 line of the (3, 0) absorption band of H2 in spectra of Titan, which were performed at an effective resolution of 0.09 A by scanning with a PEPSIOS spectrometer over a range of 0.85 A centered at the expected position of the investigated line and sampling in 80 contiguous channels. No statistically significant H2 (3, 0) S1 feature is found in the spectra, but a three-sigma upper limit of 3 mA is set for the equivalent width of the S1 line that might be present in a co-added spectrum. It is concluded that these measurements do not provide any evidence for the presence of H2 in the atmosphere of Titan.

  15. Status of Line identifications in the ChandraLETG Spectrum of Procyon

    SciTech Connect

    Desai, P; Beiersdorfer, P; Brickhouse, N S; Gu, M F; Lepson, J K

    2008-10-02

    We report on our ongoing efforts to produce a relatively complete set of X-ray emission lines present in the Low Energy Transmission Grating (LETG) spectra of Procyon. In addition to using recently reprocessed HRC-S/LETG spectra of Procyon, we use LETG spectra of Capella, along with recent Electron Bean Ion Trap (EBIT) laboratory data and new Flexible Atomic Code (FAC) calculations to identify the wealth of weaker lines present in the spectrum. Experimental measurements at the EBIT-I and EBIT-II facilities at Livermore of astrophysically abundant elements (Fe VII-Fe X, Lepson et al. 2002, Ar IX-Ar XVI, Lepson et al 2003, S VII, S XIV, Lepson et al 2004) and new FAC calculations of Mg and Ne (Gu, 2008 in press) provide an opportunity to identify many of the previously unassigned lines in Procyon (Raassen et al, 2002).

  16. LETTER TO THE EDITOR: Line sharpening by PCI in the Auger decay spectrum of CO

    NASA Astrophysics Data System (ADS)

    Sundin, S.; Ausmees, A.; Sorensen, S. L.; Björneholm, O.; Hjelte, I.; Svensson, S.

    1997-12-01

    The Auger decay from the C 0953-4075/30/23/004/img9 core-ionized state of CO has been studied with photon energies close to and far above threshold. Close to the threshold post-collision interaction (PCI) redistributes intensity from the low kinetic energy side to the high kinetic energy side of the Auger lines. Taking advantage of this a previously unresolved vibrational level of the B final state has now been observed and we have extracted a vibrational splitting of 0.27(3) eV. This shows how the PCI effect not only broadens the Auger line, but that the associated asymmetric line sharpening can be used to reveal the finer details of the Auger spectrum.

  17. An absorption line in the ultraviolet spectrum of 40 Eridani B

    NASA Technical Reports Server (NTRS)

    Greenstein, J. L.

    1980-01-01

    Two excellent low-resolution spectra show an absorption line of equivalent width 3 A, near 1391 A, in the typical DA (hydrogen atmosphere) white dwarf 40 Eri B. The line is confirmed by a high-resolution spectrum and is the first seen in any DA star. Ultraviolet fluxes and the profile of Lyman-alpha confirm an effective temperature near 17,000 K. If the line is Si IV, it requires a temperature near 40,000 K. Unattractive possibilities are a hot circumstellar absorbing envelope dependent on accretion from companions, or formation at large optical depth in a transparent atmosphere with high Si/H. A suggestion that H2 should be considered leads to the possible interpretation as the (0, 5) transition of the Lyman band, formed at small optical depth. The band should be stronger in cooler DAs.

  18. Tailoring of electron flow current in magnetically insulated transmission lines

    NASA Astrophysics Data System (ADS)

    Martin, J. P.; Savage, M. E.; Pointon, T. D.; Gilmore, M. A.

    2009-03-01

    It is desirable to optimize (minimizing both the inductance and electron flow) the magnetically insulated vacuum sections of low impedance pulsed-power drivers. The goal of low inductance is understandable from basic efficiency arguments. The goal of low electron flow results from two observations: (1) flowing electrons generally do not deliver energy to (or even reach) most loads, and thus constitute a loss mechanism; (2) energetic electrons deposited in a small area can cause anode damage and anode plasma formation. Low inductance and low electron flow are competing goals; an optimized system requires a balance of the two. While magnetically insulated systems are generally forgiving, there are times when optimization is crucial. For example, in large pulsed-power drivers used to energize high energy density physics loads, the electron flow as a fraction of total current is small, but that flow often reaches the anode in relatively small regions. If the anode temperature becomes high enough to desorb gas, the resulting plasma initiates a gap closure process that can impact system performance. Magnetic-pressure driven (z pinches and material equation of state) loads behave like a fixed inductor for much of the drive pulse. It is clear that neither fixed gap nor constant-impedance transmission lines are optimal for driving inductive loads. This work shows a technique for developing the optimal impedance profile for the magnetically insulated section of a high-current driver. Particle-in-cell calculations are used to validate the impedance profiles developed in a radial disk magnetically insulated transmission line geometry. The input parameters are the spacing and location of the minimum gap, the effective load inductance, and the desired electron flow profile. The radial electron flow profiles from these simulations are in good agreement with theoretical predictions when driven at relatively high voltage (i.e., V≥2MV).

  19. Fermi spin current contribution in spin wave spectrum of spin-1/2 fermions

    NASA Astrophysics Data System (ADS)

    Andreev, Pavel; Kuzmenkov, Leonid

    2016-05-01

    General theory predicts the presence of the thermal part of the spin current in the spin evolution equation for bosons and fermions. For bosons in Bose-Einstein condensate state, it is equal to zero. However, for degenerate fermions it is non zero and it can give a considerable contribution since it describes the Pauli blocking. In this work, we consider spin-1/2 partially polarized fermions. We derive an equation of state for the thermal part of the spin current of degenerate fermions and call it Fermi spin current. We present the spin evolution equation with the Fermi spin current as a part of applied hydrodynamic model. We consider spectrum of collective excitation and describe contribution of the Fermi spin current in the spin wave spectrum. The work of P.A. was supported by the Russian Foundation for Basic Research (Grant No. 16-32-00886) and the Dynasty foundation.

  20. Determination of Spectral Line Parameters in Selected Portions of the Infrared Spectrum of Water Vapor

    NASA Technical Reports Server (NTRS)

    Albert, Karen Keppler

    1999-01-01

    Pressure broadening and pressure-induced shift coefficients due to water and nitrogen have been determined for water vapor transitions in the CO2 region of interest to Project HALOE. The temperature dependences of the widths and shifts have also been determined for selected transitions in this region. Results have been compared with values available in the literature. The line parameters have been obtained from the analysis of room temperature recordings of the spectrum of pure water and recordings of the spectra of heated water/nitrogen mixtures. The recordings of the water vapor spectrum were obtained with Fourier Transform Spectrometers at Kitt Peak and at the Justus-Liebig-Universitat Giessen. Up to eighteen spectra have been fitted simultaneously with a multispectrum nonlinear least-squares fitting technique developed by Dr. D. Chris Benner and colleagues.

  1. Prediction of induction motor line current spectra from design data

    NASA Astrophysics Data System (ADS)

    Guldemir, Hanifi

    The thesis concentrates on the estimation of the magnitude and frequency of the spectral components of line current that may be used for sensorless speed detection. The prediction method uses a mixture of permeance-mmf, finite element and reluctance mesh techniques to establish the air gap magnetic field. This traditional type of approach is chosen to maintain a visible link between cause and effect so enhancing understanding. The approach is enhanced by the use of slot permanence effects calculated by finite element techniques where saturation due to the current carrying conductors in the slots is incorporated. This is essential for closed slots. Further enhancements include examining slot permeance effects over one or more poles so that the influence of the spatial distribution of slot currents, and slot top saturation can be incorporated. The harmonic chain equivalent circuit is extensively modified to provide a vehicle for predicting the correct saturation conditions in a skewed machine and the correct winding currents for the field solutions. Rotor pole aliasing is introduced to explain the large number of independent speed harmonic terms found experimentally. Special equivalent circuits are introduced to enable these current harmonic to be predicted. A thorough experimental validation is then conducted of the model using a 30 kW experimental machine with adjustable eccentricity with rotors of different slotting form, slot number and skew to determine their effect on the speed dependent harmonic components. Very good agreement is demonstrated. Finally, the improved prediction model is used to provide information on the significance of saturation, skew, slot number and rotor eccentricity on the level of speed dependent harmonic signals. All of this information helps formulate important rules to assist in the choice of motors for satisfactory operation with sensorless speed control of drives using RSH. This in itself is an important extension to the knowledge

  2. Current Status of Evidence-Based Practice for Students with Intellectual Disability and Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    West, Elizabeth A.; McCollow, Meaghan; Umbarger, Gardner; Kidwell, James; Cote, Debra L.

    2013-01-01

    The purpose of this paper is to provide a current look at the status of evidence-based practice (EBP) for students with intellectual disability and autism spectrum disorders. Specifically, this paper will (1) provide an introduction to the history and evolution of the use of levels of evidence, (2) discuss the importance of EBPs, (3) identify…

  3. Current Status of Differential Diagnosis for Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Matson, Johnny L.

    2007-01-01

    Early intervention for autism spectrum disorder (ASD) has proven to be a successful strategy for remediating many difficulties experienced by these children. As a result, accurate diagnoses of children with this range of disorders has become more critical. Additionally, while current training programs are for 3-4 year olds, in efforts to start…

  4. Line identifications in the ultraviolet (2590-3230 A) spectrum of the hydrogen-deficient carbon star HD 182040

    NASA Technical Reports Server (NTRS)

    Johnson, H. R.; Ameen, M. M.; Eaton, J. A.

    1984-01-01

    Identifications for absorption features detected in the ultraviolet spectrum of the hydrogen-deficient supergiant carbon star HD 182040 observed at high resolution with the IUE satellite are presented. The spectrum in this range is filled with blended lines of the iron-peak elements, with Fe I and Cr II dominating the spectrum. Spectra definitely and probably detected are given, as well as those searched for and not detected. In the investigated range, the spectrum resembles that of a middle-G supergiant. The absorption-line spectrum is similar to the spectra of the sun and other late-type stars, but neutral metal lines are weaker than in K and M giants. The level of ionization is significantly higher than in the sun, Zeta Cap, and Epsilon Gem.

  5. Predicting narrow states in the spectrum of a nucleus beyond the proton drip line.

    PubMed

    Canton, L; Pisent, G; Svenne, J P; Amos, K; Karataglidis, S

    2006-02-24

    Properties of particle-unstable nuclei lying beyond the proton drip line can be ascertained by considering the (usually known) properties of its mirror neutron-rich system. We have used a multichannel algebraic scattering theory to map the known properties of the neutron-14C system to those of the proton-14O one from which we deduce that the particle-unstable 15F will have a spectrum of two low-lying broad resonances of positive parity and, at higher excitation, three narrow negative-parity ones. A key feature is to use coupling to Pauli-hindered states in the target. PMID:16606079

  6. Current and Future Regulation of the RF Spectrum in the US and Abroad

    NASA Astrophysics Data System (ADS)

    Gergely, T. E.

    2004-05-01

    In the US, regulation of the radio spectrum proceeds on two tracks. Spectrum use by the federal government is regulated by the National Telecommunications and Information Administration (NTIA), a Bureau of the Department of Commerce; the Federal Communications Commission (FCC) regulates spectrum use by the private sector. There is continuous coordination between these two agencies, as most portions of the spectrum are used jointly by the government and the private sector. Radio astronomers provide input to NTIA through the NSF Spectrum Management office, and to the FCC through filings of the Committee on Radio Frequencies (CORF) of the National Academy of Sciences. This basic structure, that has been in place for over two decades, is under great strain due to the demands posed by the introduction of a variety of new services, e.g. a wireless services, UWB, etc., many of which do not fit easily under the traditional block allocation system. One attempt to deal with these issues, currently underway at the FCC, proposes to quantify and manage interference in terms of an "interference temperature". Astronomers must pay attention to these developments, as they may have a profound impact in their ability to access portions of the radio spectrum. Internationally, spectrum regulation is the domain of the International Telecommunication Union (ITU). Radio astronomy is one of the radio services, and issues of importance to astronomers are discussed in several of the ITU Study Groups (SGs), in particular, SG 7, dedicated to the Science Services. The status of some of the issues of importance to astronomers currently discussed at the ITU, e.g. satellite allocations in the vicinity of bands allocated to radio astronomy and control of adjacent band emissions will be discussed.

  7. Locally Optimally Emitting Clouds and the Variable Broad Emission Line Spectrum of NGC 5548

    NASA Astrophysics Data System (ADS)

    Korista, Kirk T.; Goad, Michael R.

    2000-06-01

    In recent work Baldwin et al. proposed that in the geometrically extended broad-line regions (BLRs) of quasars and active galactic nuclei, a range in line-emitting gas properties (e.g., density, column density) might exist at each radius and showed that under these conditions the broad emission line spectra of these objects may be dominated by selection effects introduced by the atomic physics and general radiative transfer within the large pool of line-emitting entities. In this picture, the light we see originates in a vast amalgam of emitters but is dominated by those emitters best able to reprocess the incident continuum into a particular emission line. We test this ``locally optimally emitting clouds'' (LOC) model against the extensive spectroscopic database of the Seyfert 1 galaxy NGC 5548. The time-averaged, integrated-light UV broad emission line spectrum from the 1993 Hubble Space Telescope (HST) monitoring campaign is reproduced via the optimization of three global geometric parameters: the outer radius, the index controlling the radial cloud covering fraction of the continuum source, and the integrated cloud covering fraction. We make an ad hoc selection from the range of successful models, and for a simple spherical BLR geometry we simulate the emission-line light curves for the 1989 IUE and 1993 HST campaigns, using the respective observed UV continuum light curves as drivers. We find good agreement between the predicted and observed light curves and lags-a demonstration of the LOC picture's viability as a means to understanding the BLR environment. Finally, we discuss the next step in developing the LOC picture, which involves the marriage of echo-mapping techniques with spectral simulation grids such as those presented here, using the constraints provided by a high-quality, temporally well-sampled spectroscopic data set.

  8. Variability of Hell and hydrogen line profiles in the spectrum of HD 93521

    NASA Astrophysics Data System (ADS)

    Rzaev, A. Kh.; Panchuk, V. E.

    2008-03-01

    We have studied the variability of the Hell λλ 4686 and 5411 Å H β, and H α lines in the spectrum of the pulsating star HD 93521. All these line profiles display the same variability pattern relative to the average profiles: a sinusoidal wave that moves systematically from the short-to the long-wavelength wing of the profile. This variability is due to non-radial pulsations. To study the pulsation movements and stratification of the radial velocity in the atmosphere of HD 93521, we analyzed the variability of the radial velocities measured individually for the blue and red halves of the absorption profile at the half-level of the line intensity. The periods and amplitudes of this radial-velocity variability are different for different lines and are well correlated with their central depths. In the transition from weak to strong lines (i.e., from lower to upper layers of the atmosphere), the period of the radial-velocity variations measured using both halves of the absorption profile increases, while its amplitude decreases. When the morphology and variability of photospheric and wind-driven lines are compared, it is clear that the variability of their absorption components is due to the same process—non-radial pulsations. In this way, the non-radial pulsations partly affect the variability of the stellar wind. The effect of the stellar wind on the profiles of strong lines is observed as a variable absorption feature that moves along the profiles synchronous with the axial rotation of the star.

  9. The neutral oxygen spectrum. 1: Collisionally excited level populations and line intensities under optically thin conditions

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Kastner, S. O.

    1995-01-01

    This is the first paper in a projected program to produce quantitative information on the spectrum of the neutral oxygen atom under a variety of excitation conditions. Radiative rates and effective collision strengths are assembled from the recent literature where available, or are calculated for as yet untreated transitions using the University College superstructure/distorted-wave computer package, to produce a complete set of atomic data for a 13 hybrid level model of neutral oxygen. Level populations and relative intensities for 28 allowed, inter-combination, and forbidden oxygen lines are computed, under optically thin conditions, for the electron density range 4.0 less than log N(sub e) less than 12.0 and the electron temperature values T(sub e) = 5000, 10,000, 20,000, 50,000, and 100,000 K. Preliminary applications to observed intercombination/allowed and forbidden/allowed line ratios are discussed.

  10. The Remarkable X-ray Spectrum of the Broad-Line Radio Galaxy 3C 445

    NASA Technical Reports Server (NTRS)

    Sambruna, R. M.; Reeves, J. N.; Braito, V.

    2007-01-01

    The nearby (z=0.057) radio-loud source 3C 445, optically classified as a Broad-Line Radio Galaxy, exhibits an X-ray spectrum strongly reminiscent of an obscured AGN, suggesting we are seeing this source at a relatively large angle from the radio jet. Here we present an archival 15 ks XMM-Newton observation of 3C 445 which confirms the remarkable complexity of its X-ray emission. The X-ray emission is described by a power law continuum with GAMMA approximately equal to 1.4, absorbed by several layers of cold gas, plus strong cold reflection. A narrow, unresolved Fe Kalpha emission line is detected, confirming previous findings, with EW approximately equal to 400 eV. A soft excess is present below 2 keV over the extrapolation of the hard X-ray power law, which we model with a power law with the same photon index and absorbed by a column density N(sub H)5 approximately equal to 10(sup 20) cm(sup -2) in excess to Galactic. Remarkably, a host of emission lines are present below 2 keV, confirming previous indications from ASCA, due to H- and He-like O, Mg, and Si. The detection of two features at 0.74 and 0.87 keV, identified with OVII and OVIII Radiative Recombination Continuum features, suggest an origin of the lines from a photoionized gas, with properties very similar to radio-quiet obscured AGN. Two different ionized media, or a single stratified medium, are required to fit the soft X-ray data satisfactorily. The similarity of the X-ray spectrum of 3C 445 to Seyferts underscores that the central engines of radio-loud and radio-quiet AGN similarly host both cold and warm gas.

  11. Diagnosis lost: Differences between children who had and who currently have an autism spectrum disorder diagnosis.

    PubMed

    Blumberg, Stephen J; Zablotsky, Benjamin; Avila, Rosa M; Colpe, Lisa J; Pringle, Beverly A; Kogan, Michael D

    2016-10-01

    Autism spectrum disorder diagnoses sometimes change due to misdiagnosis, maturation, or treatment. This study uses a probability-based national survey-the Survey of Pathways to Diagnosis and Services-to compare currently diagnosed (n = 1420) and previously diagnosed (n = 187) children aged 6-17 years based on retrospective parental reports of early concerns about their children's development, responses to those concerns by doctors and other healthcare providers, the type of provider who made the first autism spectrum disorder diagnosis, and the autism spectrum disorder subtype diagnoses received (if any). Propensity score matching was used to control for differences between the groups on children's current level of functioning and other current characteristics that may have been related to diagnosis loss. Approximately 13% of the children ever diagnosed with autism spectrum disorder were estimated to have lost the diagnosis, and parents of 74% of them believed it was changed due to new information. Previously diagnosed children were less likely to have parents with early concerns about verbal skills, nonverbal communication, learning, and unusual gestures or movements. They were also less likely to have been referred to and diagnosed by a specialist. Previously diagnosed children were less likely to have ever received a diagnosis of Asperger's disorder or autistic disorder. PMID:26489772

  12. The Deepest Spectrum in the Universe? Line Emission from Lyman-alpha Clouds at z 3

    NASA Astrophysics Data System (ADS)

    Bunker, Andrew J.; Rauch, M.; Haehnelt, M.; Becker, G.; Marleau, F.; Graham, J.; Research, European; Inter-Galactic Medium, Training Network on the

    2007-12-01

    We present the results of an extremely deep long-slit optical spectroscopic search for low-luminosity Lyman-alpha emitters. Over several years we have accumulated 150-hours integration on a single field with 8-10m telescopes (VLT/FORS2, Gemini/GMOS and Keck/LRIS) at a spectral resolution of 300km/s. This is the deepest spectrum ever obtained - our 1 sigma sensitivity to line emission in a 1 arcsec2 aperture is 1019erg/cm2/s. We have significant detections of 30 emission line objects, which are most likely Lyman-alpha emitters at 2.7line emission may be powered by star formation in conditions of low metallicity and low dust, or alternatively may arise from cooling radiation or perhaps external photoionzation by the metagalactic Lyman continuum background. Many of the line emitters are significantly spatially extended (with median size 4arcsec, 30kpc) and could plausibly be the host population of the high column density Lyman-alpha absorption clouds seen in QSO spectra (the Damped Lyman-alpha Systems and the Lyman-Limit Systems).

  13. Spectral Interferences Manganese (Mn) - Europium (Eu) Lines in X-Ray Fluorescence Spectrometry Spectrum

    NASA Astrophysics Data System (ADS)

    Tanc, Beril; Kaya, Mustafa; Gumus, Lokman; Kumral, Mustafa

    2016-04-01

    X-ray fluorescence (XRF) spectrometry is widely used for quantitative and semi quantitative analysis of many major, minor and trace elements in geological samples. Some advantages of the XRF method are; non-destructive sample preparation, applicability for powder, solid, paste and liquid samples and simple spectrum that are independent from chemical state. On the other hand, there are some disadvantages of the XRF methods such as poor sensitivity for low atomic number elements, matrix effect (physical matrix effects, such as fine versus course grain materials, may impact XRF performance) and interference effect (the spectral lines of elements may overlap distorting results for one or more elements). Especially, spectral interferences are very significant factors for accurate results. In this study, semi-quantitative analyzed manganese (II) oxide (MnO, 99.99%) was examined. Samples were pelleted and analyzed with XRF spectrometry (Bruker S8 Tiger). Unexpected peaks were obtained at the side of the major Mn peaks. Although sample does not contain Eu element, in results 0,3% Eu2O3 was observed. These result can occur high concentration of MnO and proximity of Mn and Eu lines. It can be eliminated by using correction equation or Mn concentration can confirm with other methods (such as Atomic absorption spectroscopy). Keywords: Spectral Interferences; Manganese (Mn); Europium (Eu); X-Ray Fluorescence Spectrometry Spectrum.

  14. Line Identifications in the Far Ultraviolet Spectrum of the Eclipsing Binary System 31 Cygni

    NASA Astrophysics Data System (ADS)

    Hagen Bauer, Wendy; Bennett, P. D.

    2011-05-01

    The eclipsing binary system 31 Cygni (K4 Ib + B3 V) was observed at several phases with the Far Ultraviolet Spectrosocopic Explorer (FUSE) satellite. During total eclipse, a rich emission spectrum was observed, produced by scattering of hot star photons in the extended wind of the K supergiant. The system was observed during deep chromospheric eclipse, and 2.5 months after total eclipse ended. We present an atlas of line identifications in these spectra. During total eclipse, emission features from C II , C III, N I, N II, N III, O I, Si II, P II, P III, S II, S III, Ar I, Cr III, Fe II, Fe III, and Ni II were detected. The strongest emission features arise from N II. These lines appear strongly in absorption during chromospheric eclipse, and even 2.5 months after total eclipse, the absorption bottoms out on the underlying emission seen during total eclipse. The second strongest features in the emission spectrum arise from Fe III. Any chromospheric Fe III absorption is buried within strong chromospheric absorption from other species, mainly Fe II. The emission profiles of most of the doubly-ionized species are red-shifted relative to the systemic velocity, with asymmetric profiles with a steeper long-wavelength edge. Emission profiles from singly-ionized species tend to be more symmetric and centered near the systemic velocity. In deep chromospheric eclipse, absorption features are seen from neutral and singly-ionized species, arising from lower levels up to 3 eV. Many strong chromospheric features are doubled in the observation obtained during egress from eclipse. The 31 Cygni spectrum taken 2.5 months after total eclipse ended ws compared to single-star B spectra from the FUSE archives. There was still some additional chromospheric absorption from strong low-excitation Fe II, O I and Ar I.

  15. TURBULENCE SPECTRA FROM DOPPLER-BROADENED SPECTRAL LINES: TESTS OF THE VELOCITY CHANNEL ANALYSIS AND VELOCITY COORDINATE SPECTRUM TECHNIQUES

    SciTech Connect

    Chepurnov, A.; Lazarian, A.

    2009-03-10

    Turbulent motions induce Doppler shifts of observable emission and absorption lines motivating studies of turbulence using precision spectroscopy. We provide numerical testing of the two most promising techniques, velocity channel analysis and velocity coordinate spectrum (VCS). We obtain an expression for the shot noise that the discretization of the numerical data entails and successfully test it. We show that the numerical resolution required for recovering the underlying turbulent spectrum from observations depend on the spectral index of velocity fluctuations, which makes low-resolution testing misleading. We demonstrate numerically that, when dealing with absorption lines, sampling of turbulence along just a dozen directions provides a high quality spectrum with the VCS technique.

  16. Line Intensities in the Far-Infrared Spectrum of H 2O 2

    NASA Astrophysics Data System (ADS)

    Perrin, A.; Flaud, J.-M.; Camy-Peyret, C.; Schermaul, R.; Winnewisser, M.; Mandin, J.-Y.; Dana, V.; Badaoui, M.; Koput, J.

    1996-04-01

    Using high resolution Fourier transform spectra (resolution 0.002 cm -1) recorded at the Instituto Ricerca Onde Electromagnetiche Firenze and at the Justus Liebig University Giessen, it has been possible to measure the relative intensities of lines in the far-infrared spectrum of H 2O 2in the 25-400 cm -1spectral region. These intensities were used as input data in a least-squares fit calculation in order to obtain the expansion parameters of the transition moment operator of the pure torsional-rotational transitions of H 2O 2. For these intensity calculations, the theoretical model takes into account the cos γ-type dependence of the dipole moment due to the large amplitude motion of the H atoms relative to the O-O bond, where 2γ is the torsion angle. The value of the dipole moment obtained from the fit of the observed intensities was then scaled to the value obtained from Stark effect measurements. Finally, a synthetic spectrum of the far infrared band of H 2O 2was generated, using the dipole moment expansion determined in this work for the line intensities and the parameters and the Hamiltonian matrix given in a previous analysis (C. Camy-Peyret, J.-M. Flaud, J. W. C. Johns, and M. Noel, J. Mol. Spectrosc.155,84-104 (1992)) for the line positions. In addition to the (Δ n= ±1, Δ Ka= ∓2) torsional-rotational resonances within the ground vibrational state, which are usually observed for H 2O 2, the Hamiltonian model takes explicitly into account both the vibration-rotation resonances involving the ground state and the v3= 1 vibrational state and the "staggering" effect which is due to the cispotential barrier.

  17. Discovery of iron line emission in the Hercules X-1 low-state spectrum with HEAO 1

    NASA Technical Reports Server (NTRS)

    Pravdo, S. H.; Boldt, E. A.; Holt, S. S.; Rothschild, R. E.; Serlemitsos, P. J.

    1978-01-01

    Results are reported for HEAO 1 observations of Her X-1 which confirm the existence of the iron line-emission feature discovered with OSO 8 in the high-state spectrum and also reveal an iron emission feature in the low-state spectrum. The iron line-emission feature in the low-state spectrum was detected at a significance level greater than 5 sigmas and is characterized by a line energy of 6.4 keV, an equivalent width larger than that of the high-state line, a binary phase dependence of the line intensity, and a line width that is intrinsically narrow in contrast to the broad high-state line. The observed line energy and narrow line width are shown to be consistent with an interpretation in terms of fluorescence emission due to X-ray heating. It is suggested that HZ Her contributes no more than about 10% of the predicted line flux, that this emission is reflected from a highly ionized plasma, and that a hot coronal gas is an important source of the low-state X-rays.

  18. The solar O III spectrum. II - Longer wavelengths, line widths, and the He II Lyman alpha radiation field

    NASA Technical Reports Server (NTRS)

    Kastner, S. O.; Behring, W. E.; Bhatia, A. K.

    1983-01-01

    The solar O III spectrum above 900 A is analyzed, including several visible and infrared lines which are important in nebular studies. The dependence of the line intensities on the rate of photoexcitation by He Ly-alpha is determined, and the observability of these lines in the solar spectrum is studied. The impact approximation is employed to calculate the expected line widths of the stronger solar O III lines. The photoexciting field at 304 A calculated from the observed intensities of the O III lines below 900 A (Bhatia et al., 1982) is compared with the field predicted by a recent model (Avrett et al., 1976). It is shown that additional radiation trapping must be present beyond that given by this model.

  19. A near infrared line list for NH3: Analysis of a Kitt Peak spectrum after 35 years

    NASA Astrophysics Data System (ADS)

    Barton, Emma J.; Yurchenko, Sergei N.; Tennyson, Jonathan; Béguier, Serge; Campargue, Alain

    2016-07-01

    A Fourier Transform (FT) absorption spectrum of room temperature NH3 in the region 7400-8640 cm-1 is analysed using a variational line list and ground state energies determined using the MARVEL procedure. The spectrum was measured by Dr. Catherine de Bergh in 1980 and is available from the Kitt Peak data center. The centers and intensities of 8468 ammonia lines were retrieved using a multiline fitting procedure. 2474 lines are assigned to 21 bands providing 1692 experimental energies in the range 7500-9200 cm-1. The spectrum was assigned by the joint use of the BYTe variational line list and combination differences. The assignments and experimental energies presented in this work are the first for ammonia in the region 7400-8640 cm-1, considerably extending the range of known vibrational-excited states.

  20. Genetics of Autism Spectrum Disorder: Current Status and Possible Clinical Applications

    PubMed Central

    2015-01-01

    Autism spectrum disorder (ASD) is one of the most complex behavioral disorders with a strong genetic influence. The objectives of this article are to review the current status of genetic research in ASD, and to provide information regarding the potential candidate genes, mutations, and genetic loci possibly related to pathogenesis in ASD. Investigations on monogenic causes of ASD, candidate genes among common variants, rare de novo mutations, and copy number variations are reviewed. The current possible clinical applications of the genetic knowledge and their future possibilities are highlighted. PMID:26713075

  1. Ultraviolet interstellar lines in the spectrum of Pi Scorpii recorded at 2 kilometers per second resolution

    NASA Technical Reports Server (NTRS)

    Joseph, Charles L.; Jenkins, Edward B.

    1991-01-01

    A spectrum of Pi Scorpii has been recorded from 1003 to 1172 A with a maximum SNR of about 20 and a velocity resolution of 2.4 km/s. Three types of H I as well as two discrete H II regions are distinguished in velocity space, allowing independent analyses of physical conditions and abundances for the individual gas components. A direct evaluation of optical depths and column densities across the absorption features is applied for the first time to the dominant ionization stage of Fe, Si, and P. Based on an analysis of the spectrum, it is concluded that all of the Ti II absorption seen toward Pi Sco arises in the warm, neutral intercloud medium while the other elements have their maximum absorption associated with cold clouds. A conservative value of log delta less than -3.4 is inferred for the Ti depletion in the cold clouds, a value more extreme than any integrated, line-of-sight measurement made to date.

  2. ExoMol line lists XVIII. The high temperature spectrum of VO.

    NASA Astrophysics Data System (ADS)

    McKemmish, Laura K.; Yurchenko, Sergei N.; Tennyson, Jonathan

    2016-08-01

    An accurate line list, VOMYT, of spectroscopic transitions is presented for hot VO. The 13 lowest electronic states are considered. Curves and couplings are based on initial ab initio electronic structure calculations and then tuned using available experimental data. Dipole moment curves, used to obtain transition intensities, are computed using high levels of theory (e.g. MRCI/aug-cc-pVQZ using state-specific or minimal-state CAS for dipole moments). This line list contains over 277 million transitions between almost 640,000 energy levels. It covers the wavelengths longer than 0.29 μm and includes all transitions from energy levels within the lowest nine electronic states which have energies less than 20,000 cm-1 to upper states within the lowest 13 electronic states which have energies below 50,000 cm-1. The line lists give significantly increased absorption at infrared wavelengths compared to currently available VO line lists. The full line lists is made available in electronic form via the CDS database and at www.exomol.com.

  3. The Near-infrared Coronal Line Spectrum of 54 nearby Active Galactic Nuclei

    NASA Astrophysics Data System (ADS)

    Rodríguez-Ardila, A.; Prieto, M. A.; Portilla, J. G.; Tejeiro, J. M.

    2011-12-01

    The relationship between the emission of coronal lines (CLs) and nuclear activity in 36 Type 1 and 18 Type 2 active galactic nuclei (AGNs) is analyzed, for the first time, based on near-infrared (0.8-2.4 μm) spectra. The eight CLs studied, of Si, S, Fe, Al, and Ca elements and corresponding to ionization potentials (IPs) in the range 125-450 eV, are detected (3σ) in 67% (36 AGNs) of the sample. Our analysis shows that the four most frequent CLs [Si VI] 1.963 μm, [S VIII] 0.9913 μm, [S IX] 1.252 μm, and [Si X] 1.430 μm display a narrow range in luminosity, with most lines located in the interval log L 39-40 erg s-1. We found that the non-detection is largely associated with either loss of spatial resolution or increasing object distance: CLs are essentially nuclear and easily lose contrast in the continuum stellar light for nearby sources or get diluted by the strong AGN continuum as the redshift increases. Yet, there are AGNs where the lack of coronal emission, i.e., lines with IP >= 100 eV, may be genuine. The absence of these lines reflects a non-standard AGN ionizing continuum, namely, a very hard spectrum lacking photons below a few Kev. The analysis of the line profiles points out a trend of increasing FWHM with increasing IPs up to energies around 300 eV, where a maximum in the FWHM is reached. For higher IP lines, the FWHM remains nearly constant or decreases with increasing IPs. We ascribe this effect to an increasing density environment as we approach the innermost regions of these AGNs, where densities above the critical density of the CLs with IPs larger than 300 eV are reached. This sets a strict range limit for the density in the boundary region between the narrow and the broad region of 108-109 cm-3. A relationship between the luminosity of the CLs and that of the soft and hard X-ray emission and the soft X-ray photon index is observed: the coronal emission becomes stronger with both increasing X-ray emission (soft and hard) and steeper X

  4. A power line data communication interface using spread spectrum technology in home automation

    SciTech Connect

    Shwehdi, M.H.; Khan, A.Z.

    1996-07-01

    Building automation technology is rapidly developing towards more reliable communication systems, devices that control electronic equipments. These equipment if controlled leads to efficient energy management, and savings on the monthly electricity bill. Power Line communication (PLC) has been one of the dreams of the electronics industry for decades, especially for building automation. It is the purpose of this paper to demonstrate communication methods among electronic control devices through an AC power line carrier within the buildings for more efficient energy control. The paper outlines methods of communication over a powerline, namely the X-10 and CE bus. It also introduces the spread spectrum technology as to increase speed to 100--150 times faster than the X-10 system. The powerline carrier has tremendous applications in the field of building automation. The paper presents an attempt to realize a smart house concept, so called, in which all home electronic devices from a coffee maker to a water heater microwave to chaos robots will be utilized by an intelligent network whenever one wishes to do so. The designed system may be applied very profitably to help in energy management for both customer and utility.

  5. Electric currents and voltage drops along auroral field lines

    NASA Technical Reports Server (NTRS)

    Stern, D. P.

    1983-01-01

    An assessment is presented of the current state of knowledge concerning Birkeland currents and the parallel electric field, with discussions focusing on the Birkeland primary region 1 sheets, the region 2 sheets which parallel them and appear to close in the partial ring current, the cusp currents (which may be correlated with the interplanetary B(y) component), and the Harang filament. The energy required by the parallel electric field and the associated particle acceleration processes appears to be derived from the Birkeland currents, for which evidence is adduced from particles, inverted V spectra, rising ion beams and expanded loss cones. Conics may on the other hand signify acceleration by electrostatic ion cyclotron waves associated with beams accelerated by the parallel electric field.

  6. Ultraviolet and Optical Line Profile Variations in the Spectrum of {epsilon} Persei

    SciTech Connect

    Gies, D. R.; Kambe, E.; Josephs, T. S.; Bagnuolo, W. G. Jr.; Choi, Y. J.; Gudehus, D.; Guyton, K. M.; Hartkopf, W. I.; Hildebrand, J. L.; Kaye, A. B.

    1999-11-01

    The rapid variable star, {epsilon} Per (B0.5 IV-III), displays the largest amplitude profile fluctuations known among the growing number of massive, spectrum-variable stars. Here we present an analysis of a continuous 5 day run of IUE UV spectroscopy, and we show for the first time that the systematic, blue-to-red moving patterns observed in high-quality optical spectra are also present in the UV photospheric lines. We present cross-correlation functions of the individual spectra with that of a narrow-lined standard that produce a high signal-to-noise ratio representation of the blue-to-red moving bump patterns found in individual lines. We then use time series analysis methods to determine the periodic components of the profile variations (after reregistering the spectra to correct for binary motion). There are at least six periods present (ranging from 8.46 to 2.27 hr), and most of these signals are also found in optical line variations observed in 1986 (although the relative amplitudes have changed significantly). Furthermore, analysis of a shorter time series of IUE spectra from 1984 shows that similar periods were present then. We also present H{alpha} and He i {lambda}6678 profiles obtained with the Georgia State University Multi-Telescope Telescope, which were made simultaneously with IUE, and we show that the profile variations are essentially identical in the UV and optical ranges. We rule out rotational modulation and circumstellar gas obscuration as possible causes, and we suggest instead that the variations are the result of photospheric nonradial pulsations of relatively low degree (l=3-5). There were significant changes ({approx}10%) in the equivalent widths of the UV stellar wind lines during the IUE run, and we suggest that wind strengthening events are related to episodes of large-amplitude, constructive interference between the NRP modes. Thus, intermode beating may play an important role in promoting wind loss from massive stars. (c) (c) 1999

  7. [An On-Line Monitoring System for Nitrate in Seawater Based on UV Spectrum].

    PubMed

    Li, Dan; Feng, Wei-wei; Chen, Ling-xin; Zhang, Jun

    2016-02-01

    Nitrate is one of the evaluation indicators of water quality, which is particularly important for water quality monitoring. A real-time on-line monitoring system of nitrate in water is introduced in this paper. And the ultraviolet absorption technology (190-370 nm) with partial least squares method is used to detect nitrate concentration. The automated online system based on ultraviolet absorption spectrum is capable of analyzing samples without any sample preservation and without contamination problems. This system is fast, reliable, and sensitive enough for continuous use on monitoring stations and nitrate concentration can also be determined directly via its ultraviolet absorption spectrum. This system uses flow sample cell with 1cm optical path length, and a reference light is used to eliminate system error. The correlation coefficient for a linear function of the nitrate concentrations is 0.999 98. So the results of the system model test are in good correlation with the laboratory ones. Data collected has been analyzed statistically to determine how system model behave throughout the test, with special attention being paid to error analysis. As the average relative error is 0.65%, this system has greater stability and higher accuracy. The results of nitrate measurements by the field seawater tests in Yantai coast are obtained, which nitrate concentrations are about 0.2 mg · L⁻¹ in seawater, and the recoveries of samples for standard recovery tests are in 95%~110%, it shows that this system is accurate, reliability and practicability and could be developed for detected nitrate concentration in natural water. PMID:27209746

  8. THE NEAR-INFRARED CORONAL LINE SPECTRUM OF 54 NEARBY ACTIVE GALACTIC NUCLEI

    SciTech Connect

    Rodriguez-Ardila, A.

    2011-12-20

    The relationship between the emission of coronal lines (CLs) and nuclear activity in 36 Type 1 and 18 Type 2 active galactic nuclei (AGNs) is analyzed, for the first time, based on near-infrared (0.8-2.4 {mu}m) spectra. The eight CLs studied, of Si, S, Fe, Al, and Ca elements and corresponding to ionization potentials (IPs) in the range 125-450 eV, are detected (3{sigma}) in 67% (36 AGNs) of the sample. Our analysis shows that the four most frequent CLs [Si VI] 1.963 {mu}m, [S VIII] 0.9913 {mu}m, [S IX] 1.252 {mu}m, and [Si X] 1.430 {mu}m display a narrow range in luminosity, with most lines located in the interval log L 39-40 erg s{sup -1}. We found that the non-detection is largely associated with either loss of spatial resolution or increasing object distance: CLs are essentially nuclear and easily lose contrast in the continuum stellar light for nearby sources or get diluted by the strong AGN continuum as the redshift increases. Yet, there are AGNs where the lack of coronal emission, i.e., lines with IP {>=} 100 eV, may be genuine. The absence of these lines reflects a non-standard AGN ionizing continuum, namely, a very hard spectrum lacking photons below a few Kev. The analysis of the line profiles points out a trend of increasing FWHM with increasing IPs up to energies around 300 eV, where a maximum in the FWHM is reached. For higher IP lines, the FWHM remains nearly constant or decreases with increasing IPs. We ascribe this effect to an increasing density environment as we approach the innermost regions of these AGNs, where densities above the critical density of the CLs with IPs larger than 300 eV are reached. This sets a strict range limit for the density in the boundary region between the narrow and the broad region of 10{sup 8}-10{sup 9} cm{sup -3}. A relationship between the luminosity of the CLs and that of the soft and hard X-ray emission and the soft X-ray photon index is observed: the coronal emission becomes stronger with both increasing X

  9. Angular power spectrum of sterile neutrino decay lines: the role of eROSITA

    NASA Astrophysics Data System (ADS)

    Zandanel, Fabio; Weniger, Christoph; Ando, Shin’ichiro

    2016-05-01

    We study the potential of the angular auto and cross-correlation power spectrum of the cosmic X-ray background in identifying sterile neutrino dark matter taking as reference the performances of the soon-to-be-launched eROSITA satellite. The main astrophysical background sources in this case are active galactic nuclei, galaxies powered by X-ray binaries, and clusters of galaxies. We show that while sterile neutrino decays are always subdominant in the autocorrelation power spectra, they can be efficiently enhanced when cross-correlating with tracers of the dark matter distribution. We estimate that the four-years eROSITA all-sky survey will potentially provide very stringent constraints on the sterile neutrino decay lifetime by cross-correlating the cosmic X-ray background with the 2MASS galaxy catalogue. This will allow to firmly test the recently claimed 3.56-keV X-ray line found towards several clusters and galaxies and its decaying dark matter interpretation. We finally stress that the main limitation of this approach is due to the shot noise of the galaxy catalogues used as tracers for the dark matter distribution, a limitation that we need to overcome to fully exploit the potential of the eROSITA satellite in this context.

  10. Near-field coupling model between PCB and grounded transmission line based on plane wave spectrum

    NASA Astrophysics Data System (ADS)

    Leseigneur, Christelle; Baudry, David; Ravelo, Blaise; Louis, Anne

    2013-10-01

    This article presents an explicit model of electromagnetic (EM) coupling between electronic circuits and metallic wire placed above the ground plane. The model is based on the interaction between the EM near-field (NF) that has been treated with plane wave spectrum (PWS) and the Taylor model. The routine process illustrating the methodology is addressed is this article. The practicability of the model developed was upheld with different analytical and real demonstrators. First, the NF coupling between a straight transmission line (TL) and 1 GHz Wilkinson power divider (PWD) designed and implemented in planar technology was provided. Subsequently, simulations with a powerful commercial tool and measurements from 0.2 GHz to 2 GHz revealed a good agreement between the coupling voltages from the proposed model. As a second proof of concept, a printed circuit board incorporating a 40 MHz RF oscillator was placed 5 mm above the grounded TL. Once again, coupling voltages matched measurements were observed with magnitude relative difference lower than 5 dB. The hereby model presents huge benefits not only in terms of flexibility in the design process but it can also be run with very less computation time compared to the existing standard simulators. The model can be potentially a good candidate for investigating complex systems EMC engineering.

  11. Transmittance of MCF-7 breast tumor cell line through visible and near infrared spectrum

    NASA Astrophysics Data System (ADS)

    Tabakoǧlu, H. Ã.-zgür

    2016-03-01

    In this study, light transmittance of MCF-7 tumor cells from 450 nm to 1100 nm has been measured in their growing medium and evaluated. Transmittance differences have been tried to be put forward in cancer cell line on visible (VIS) and near infrared (NIR) spectrum as well as in between different numbers of cells in medium. An absorption-reflection spectrophotometer was used in the experiments. System has a tungsten light source, optical chopper, a monochromator, sample chamber, silicon detectors, lock-in amplifier and computer. System was controlled by software in order to adjust scan range, scan steps and grating configuration. Cells were grown in medium, and measurements were taken from cells while they were in 5 ml medium. According to our findings, there are significant differences between VIS and NIR regions for the same number of cells. There were found no statistical difference among different numbers of cells. Increasing number of cells has not affected the transmittance. Transmittance of medium is not significantly different from different concentration of cells.

  12. Doppler shift measurement of Balmer-alpha line spectrum emission from a plasma in a negative hydrogen ion source

    SciTech Connect

    Wada, M. Doi, K.; Kisaki, M.; Nakano, H.; Tsumori, K.; Nishiura, M.

    2015-04-08

    Balmer-α light emission from the extraction region of the LHD one-third ion source has shown a characteristic Doppler broadening in the wavelength spectrum detected by a high resolution spectrometer. The spectrum resembles Gaussian distribution near the wavelength of the intensity peak, while it has an additional component of a broader foot. The measured broadening near the wavelength of the intensity peak corresponds to 0.6 eV hydrogen atom temperature. The spectrum exhibits a larger expansion in the blue wing which becomes smaller when the line of sight is tilted toward the driver region from the original observation axis parallel to the plasma grid. A surface collision simulation model predicts the possibility of hydrogen reflection at the plasma grid surface to form a broad Balmer-α light emission spectrum.

  13. Current approaches to treatments for schizophrenia spectrum disorders, part I: an overview and medical treatments.

    PubMed

    Chien, Wai Tong; Yip, Annie Lk

    2013-01-01

    During the last three decades, an increasing understanding of the etiology, psychopathology, and clinical manifestations of schizophrenia spectrum disorders, in addition to the introduction of second-generation antipsychotics, has optimized the potential for recovery from the illness. Continued development of various models of psychosocial intervention promotes the goal of schizophrenia treatment from one of symptom control and social adaptation to an optimal restoration of functioning and/or recovery. However, it is still questionable whether these new treatment approaches can address the patients' needs for treatment and services and contribute to better patient outcomes. This article provides an overview of different treatment approaches currently used in schizophrenia spectrum disorders to address complex health problems and a wide range of abnormalities and impairments resulting from the illness. There are different treatment strategies and targets for patients at different stages of the illness, ranging from prophylactic antipsychotics and cognitive-behavioral therapy in the premorbid stage to various psychosocial interventions in addition to antipsychotics for relapse prevention and rehabilitation in the later stages of the illness. The use of antipsychotics alone as the main treatment modality may be limited not only in being unable to tackle the frequently occurring negative symptoms and cognitive impairments but also in producing a wide variety of adverse effects to the body or organ functioning. Because of varied pharmacokinetics and treatment responsiveness across agents, the medication regimen should be determined on an individual basis to ensure an optimal effect in its long-term use. This review also highlights that the recent practice guidelines and standards have recommended that a combination of treatment modalities be adopted to meet the complex health needs of people with schizophrenia spectrum disorders. In view of the heterogeneity of the risk

  14. Current approaches to treatments for schizophrenia spectrum disorders, part I: an overview and medical treatments

    PubMed Central

    Chien, Wai Tong; Yip, Annie LK

    2013-01-01

    During the last three decades, an increasing understanding of the etiology, psychopathology, and clinical manifestations of schizophrenia spectrum disorders, in addition to the introduction of second-generation antipsychotics, has optimized the potential for recovery from the illness. Continued development of various models of psychosocial intervention promotes the goal of schizophrenia treatment from one of symptom control and social adaptation to an optimal restoration of functioning and/or recovery. However, it is still questionable whether these new treatment approaches can address the patients’ needs for treatment and services and contribute to better patient outcomes. This article provides an overview of different treatment approaches currently used in schizophrenia spectrum disorders to address complex health problems and a wide range of abnormalities and impairments resulting from the illness. There are different treatment strategies and targets for patients at different stages of the illness, ranging from prophylactic antipsychotics and cognitive–behavioral therapy in the premorbid stage to various psychosocial interventions in addition to antipsychotics for relapse prevention and rehabilitation in the later stages of the illness. The use of antipsychotics alone as the main treatment modality may be limited not only in being unable to tackle the frequently occurring negative symptoms and cognitive impairments but also in producing a wide variety of adverse effects to the body or organ functioning. Because of varied pharmacokinetics and treatment responsiveness across agents, the medication regimen should be determined on an individual basis to ensure an optimal effect in its long-term use. This review also highlights that the recent practice guidelines and standards have recommended that a combination of treatment modalities be adopted to meet the complex health needs of people with schizophrenia spectrum disorders. In view of the heterogeneity of the

  15. Lyman-alpha line as a solar activity index for calculations of solar spectrum in the EUV region

    NASA Astrophysics Data System (ADS)

    Nusinov, Anatoliy; Kazachevskaya, Tamara; Katyushina, Valeria; Woods, Thomas

    It is investigated a possibility of retrieval of solar spectrum data using intensity observational data of the only solar spectral line L (Hydrogen Lyman-alpha, 121.6 nm).Using as an example spectra obtained by SEE instruments on TIMED satellite, it was shown, that both for lines and for continuum in the spectral range 27-105 nm, which is essential for ionization processes in the ionosphere, a correlation between their intensities and L was high. Therefore it becomes possible to use L measurements data as a natural solar activity index for calculations of EUV solar emission spectrum for solving aeronomical problems. It is noticed, that EUV model, obtained with using SEE data, does not allow to calculate correctly critical frequencies of ionospheric E-layer owing to low intensities of lines 97.7 and 102.6 nm, which produce the main part of ionization in ionospheric E-region.

  16. The choice of the concept of magnetic field lines or of electric current lines: Alfvén medal lecture

    NASA Astrophysics Data System (ADS)

    Akasofu, S.-I.

    2011-07-01

    In 1967, at the Birkeland Symposium in Sandefjord, Norway, Professor Hannes Alfvén stated that the second approach (in solving unsolved problems by the standard MHD theory) to cosmic electrodynamics is to "thaw" the "frozen-in" magnetic field lines. "We can illustrate essential properties of the electromagnetic state of space either by depicting the magnetic field lines or by depicting electric current lines," he said. There has been much progress in space physics since the Birkeland Symposium more than 40 years ago, but unfortunately our scientific community has not really succeeded in thawing the frozen-in field lines. Instead, it has pursued magnetic reconnection, a concept that Alfvén had been critical of. It is shown here that we have to study many unsolved problems and problems thought to be solved in terms of both the magnetic field line concept and the current system concept. In taking Alfvén's approach, we must consider the whole system, including the power supply (dynamo process) and its transmission and distribution (electric currents) and observed phenomena (power dissipation processes). Such a consideration can provide physical insight into many of our unsolved problems and problems thought to be solved. In this paper, we consider substorm onset processes, the substorm current system, sunspots, solar flares, coronal mass ejections, the interplanetary current sheet, and the magnetic field configuration of the heliosphere in terms of the current system concept. In particular, it is shown that a study of the current system is essential in substorm studies, more than changes of the magnetic field configuration in the magnetotail.

  17. Postural Control Impairments in Individuals With Autism Spectrum Disorder: A Critical Review of Current Literature

    PubMed Central

    Memari, Amir Hossein; Ghanouni, Parisa; Shayestehfar, Monir; Ghaheri, Banafsheh

    2014-01-01

    Context: Motor impairments in individuals with autism spectrum disorder (ASD) have been frequently reported. In this review, we narrow our focus on postural control impairments to summarize current literature for patterns, underlying mechanisms, and determinants of posture in this population. Evidence Acquisition: A literature search was conducted through Medline, ISI web of Knowledge, Scopus and Google Scholar to include studies between 1992 and February 2013. Results: Individuals with ASD have problems in maintaining postural control in infancy that well persists into later years. However, the patterns and underlying mechanisms are still unclear. Conclusions: Examining postural control as an endophenotype or early diagnostic marker of autism is a conceptual premise which should be considered in future investigations. At the end of the review, methodological recommendations on the assessment of postural control have also been provided. PMID:25520765

  18. A Comprehensive Survey of Current and Former College Students with Autism Spectrum Disorders

    PubMed Central

    Gelbar, Nicholas W.; Shefcyk, Allison; Reichow, Brian

    2015-01-01

    Background: There is a paucity of research concerning individuals with autism spectrum disorders (ASD) pursuing higher education. Method: This study sought to augment this gap in the literature by surveying individuals with ASD who are currently college students or who have previously attended college. Results: Thirty-five individuals completed an online survey. These individuals reported receiving extensive academic supports that enabled their academic success. Their reported difficulties in the social and emotional domains received less support. In addition, not all areas of campus life were supportive, as study abroad and career service offices were reported to not understand individuals with ASD. Conclusions: Overall, the results of this survey indicate the importance of self-advocacy and the need for institutions of higher education to provide comprehensive supports for individuals with ASD in the academic, social, and emotional domains in order to effectively integrate this group into the campus environment. PMID:25745374

  19. Properties of flat-spectrum radio-loud narrow-line Seyfert 1 galaxies

    NASA Astrophysics Data System (ADS)

    Foschini, L.; Berton, M.; Caccianiga, A.; Ciroi, S.; Cracco, V.; Peterson, B. M.; Angelakis, E.; Braito, V.; Fuhrmann, L.; Gallo, L.; Grupe, D.; Järvelä, E.; Kaufmann, S.; Komossa, S.; Kovalev, Y. Y.; Lähteenmäki, A.; Lisakov, M. M.; Lister, M. L.; Mathur, S.; Richards, J. L.; Romano, P.; Sievers, A.; Tagliaferri, G.; Tammi, J.; Tibolla, O.; Tornikoski, M.; Vercellone, S.; La Mura, G.; Maraschi, L.; Rafanelli, P.

    2015-03-01

    We have conducted a multiwavelength survey of 42 radio loud narrow-1ine Seyfert 1 galaxies (RLNLS1s), selected by searching among all the known sources of this type and omitting those with steep radio spectra. We analyse data from radio frequencies to X-rays, and supplement these with information available from online catalogues and the literature in order to cover the full electromagnetic spectrum. This is the largest known multiwavelength survey for this type of source. We detected 90% of the sources in X-rays and found 17% at γ rays. Extreme variability at high energies was also found, down to timescales as short as hours. In some sources, dramatic spectral and flux changes suggest interplay between a relativistic jet and the accretion disk. The estimated masses of the central black holes are in the range ~106-8 M⊙, lower than those of blazars, while the accretion luminosities span a range from ~0.01 to ~0.49 times the Eddington limit, with an outlier at 0.003, similar to those of quasars. The distribution of the calculated jet power spans a range from ~1042.6 to ~1045.6 erg s-1, generally lower than quasars and BL Lac objects, but partially overlapping with the latter. Once normalised by the mass of the central black holes, the jet power of the three types of active galactic nuclei are consistent with each other, indicating that the jets are similar and the observational differences are due to scaling factors. Despite the observational differences, the central engine of RLNLS1s is apparently quite similar to that of blazars. The historical difficulties in finding radio-loud narrow-line Seyfert 1 galaxies might be due to their low power and to intermittent jetactivity. Tables 4-9 and Figs. 8-13 are available in electronic form at http://www.aanda.org

  20. Line position and line intensity analyses of the high-resolution spectrum of H218O up to the First Triad and J = 17

    NASA Astrophysics Data System (ADS)

    Coudert, L. H.; Chelin, P.

    2016-08-01

    Line position and line intensity analyses of the high-resolution spectrum of the H218O isotopic species of the water molecule are performed with the Bending-Rotation approach up to J = 17 and the First Triad of interacting states, (0 2 0), (1 0 0), and (0 0 1). The line position analysis involves microwave and terahertz transitions, ground state combination differences, far infrared and infrared lines, and experimental energy levels which were reproduced with a 1.2 unitless standard deviation. The data set considered in the line intensity analysis consists of 3707 infrared transitions recorded using absorption spectroscopy at room temperature which were fitted with a 1.4 unitless standard deviation. The results of both analyses are compared with previous investigations and are used to build a line position and line intensity database to update the HITRAN and GEISA databases. A comparison with the HITRAN 2012 database reveals that the new database yields intensity values closer to the experimental ones.

  1. A non-local thermodynamic equilibrium, line-blanketed synthetic spectrum of Iota Herculis - C, Al, and Si lines

    NASA Technical Reports Server (NTRS)

    Grigsby, James A.

    1991-01-01

    A non-LTE line-blanketed model stellar atmosphere is used to compute a model of I Herculis (B3 IV) with a Teff of 17,500 K and a log g of 3.75, following the conclusions of Peters and Polidan (1985). Detailed profiles of a number of lines of C, Al, and Si in the 1200-2000-A region are computed, including the resonance lines of C II, Al II, and Al III. These profiles are compared to observations obtained from the coaddition of eight IUE SWP images, using a technique developed by Leckrone and Adelman (1989). Comparison of carbon lines with a model that is underabundant in carbon by a factor of 2 relative to the sun indicates that the C abundance of Iota Her is at most one-half solar. Non-LTE effects are examined by comparing an LTE model possessing identical atmospheric parameters with the non-LTE model. Substantial differences in the populations of the model atomic states are found, but differences in the temperature structure of the two models often mask the non-LTE effects in the synthetic spectra.

  2. Highly Ionized Iron Absorption Lines from Outflowing Gases in the X-ray Spectrum of NGC 1365

    NASA Technical Reports Server (NTRS)

    Risaliti, G.; Bianchi, S.; Matt, G.; Baldi, A.; Elvis, M.; Fabbiano, G.; Zezas, A.

    2006-01-01

    We present the discovery of four absorption lines in the X-ray spectrum of the Seyfert galaxy NGC 1365, at energies between 6.7 and 8.3 keV. The lines are detected with high statistical confidence (from >20 sigma for the strongest to -4 sigma for the weakest) in two XMM-Newton observations 60 ks long. We also detect the same lines, with a lower signal-to-noise ratio (but still >2 sigma for each line), in two previous shorter (-10 ks) XMM-Newton observations. The spectral analysis identifies these features as Fe XXV and Fe XXVI Kalpha and Kbeta lines, outflowing with velocities varying between -1000 and -5000 km/s among the observations. These are the highest quality detections of such lines so far. The high equivalent widths [EW (Kalpha) approximately 100 eV] and the Kalpha/Kbeta ratios imply that the lines are due to absorption of the AGN continuum by a highly ionized gas with column density NH-5?1023 cm(exp -2) at a distance of -(50-100)RS from the continuum source.

  3. On current induced in-line oscillation of pipelines in free spans

    SciTech Connect

    Toerum, A.; Moe, G.; Johansen, J.V.; Katla, E.

    1996-12-01

    A review is given on some results from different investigations on current induced in-line vibrations (viv) of circular cylinders. Results of recent laboratory experiments are presented. An attempt has been made to explain why the laboratory experiments and field tests give different results. It is recommended that the results of the field measurements of HSE (1993) on in-line oscillations is used in engineering work to predict in-lines oscillation amplitudes until more results are available and further insight into the mechanisms of in-line oscillations is obtained.

  4. Hydrogen Balmer line formation in solar flares affected by return currents

    NASA Astrophysics Data System (ADS)

    Štepán, J. Å.; Kašparová, J.; Karlický, M.; Heinzel, P.

    2007-09-01

    Aims:We investigate the effect of the electric return currents in solar flares on the profiles of hydrogen Balmer lines. We consider the monoenergetic approximation for the primary beam and runaway model of the neutralizing return current. Methods: Propagation of the 10 keV electron beam from a coronal reconnection site is considered for the semiempirical chromosphere model F1. We estimate the local number density of return current using two approximations for beam energy fluxes between 4 × 1011 and 1 × 1012 erg cm-2 s-1. Inelastic collisions of beam and return-current electrons with hydrogen are included according to their energy distributions, and the hydrogen Balmer line intensities are computed using an NLTE radiative transfer approach. Results: In comparison to traditional NLTE models of solar flares that neglect the return-current effects, we found a significant increase emission in the Balmer line cores due to nonthermal excitation by return current. Contrary to the model without return current, the line shapes are sensitive to a beam flux. It is the result of variation in the return-current energy that is close to the hydrogen excitation thresholds and the density of return-current electrons.

  5. Current Perspectives on Physical Activity and Exercise Recommendations for Children and Adolescents With Autism Spectrum Disorders

    PubMed Central

    Srinivasan, Sudha M.; Pescatello, Linda S.

    2014-01-01

    Recent evidence suggests that childhood obesity is increasing in children who are developing typically as well as in children with developmental disabilities such as autism spectrum disorders (ASDs). Impairments specific to autism as well as general environmental factors could lead to an imbalance between the intake and expenditure of energy, leading to obesity. In this article, we describe the mechanisms by which autism-specific impairments contribute to obesity. The evidence on exercise interventions to improve physical fitness, address obesity, and reduce autism-specific impairments in children and adolescents with ASDs is discussed. Limited evidence is currently available for exercise interventions in individuals with ASDs. Therefore, literature on other pediatric developmental disabilities and children who are developing typically was reviewed to provide recommendations for clinicians to assess physical activity levels, to promote physical fitness, and to reduce obesity in children and adolescents with ASDs. There is a clear need for further systematic research to develop sensitive assessment tools and holistic multisystem and multifactorial obesity interventions that accommodate the social communication, motor, and behavioral impairments of individuals with ASDs. PMID:24525861

  6. Prevention of Fetal Alcohol Spectrum Disorder: Current Canadian Efforts and Analysis of Gaps.

    PubMed

    Poole, Nancy; Schmidt, Rose A; Green, Courtney; Hemsing, Natalie

    2016-01-01

    Effective prevention of risky alcohol use in pregnancy involves much more than providing information about the risk of potential birth defects and developmental disabilities in children. To categorize the breadth of possible initiatives, Canadian experts have identified a four-part framework for fetal alcohol spectrum disorder (FASD) prevention: Level 1, public awareness and broad health promotion; Level 2, conversations about alcohol with women of childbearing age and their partners; Level 3, specialized support for pregnant women; and Level 4, postpartum support for new mothers. In order to describe the level of services across Canada, 50 Canadian service providers, civil servants, and researchers working in the area of FASD prevention were involved in an online Delphi survey process to create a snapshot of current FASD prevention efforts, identify gaps, and provide ideas on how to close these gaps to improve FASD prevention. Promising Canadian practices and key areas for future action are described. Overall, Canadian FASD prevention programming reflects evidence-based practices; however, there are many opportunities to improve scope and availability of these initiatives. PMID:27199560

  7. Prevention of Fetal Alcohol Spectrum Disorder: Current Canadian Efforts and Analysis of Gaps

    PubMed Central

    Poole, Nancy; Schmidt, Rose A.; Green, Courtney; Hemsing, Natalie

    2016-01-01

    Effective prevention of risky alcohol use in pregnancy involves much more than providing information about the risk of potential birth defects and developmental disabilities in children. To categorize the breadth of possible initiatives, Canadian experts have identified a four-part framework for fetal alcohol spectrum disorder (FASD) prevention: Level 1, public awareness and broad health promotion; Level 2, conversations about alcohol with women of childbearing age and their partners; Level 3, specialized support for pregnant women; and Level 4, postpartum support for new mothers. In order to describe the level of services across Canada, 50 Canadian service providers, civil servants, and researchers working in the area of FASD prevention were involved in an online Delphi survey process to create a snapshot of current FASD prevention efforts, identify gaps, and provide ideas on how to close these gaps to improve FASD prevention. Promising Canadian practices and key areas for future action are described. Overall, Canadian FASD prevention programming reflects evidence-based practices; however, there are many opportunities to improve scope and availability of these initiatives. PMID:27199560

  8. The Hubble Space Telescope Quasar Absorption Line Key Project: The Unusual Absorption-Line System in the Spectrum of PG 2302+029--Ejected or Intervening?

    NASA Technical Reports Server (NTRS)

    Jannuzi, B. T.; Hartig, G. F.; Kirhakos, S.; Sargent, W. L. W.; Turnshek, D. A.; Weymann, R. J.; Bahcall, J. N.; Bergeron, J.; Boksenberg, A.; Savage, B. D.; Schneider, D. P.; Wolfe, A. M.

    1996-01-01

    We report the discovery of a high-ionization broad absorption line system at a redshift of z(sub abs) = 0.695 in the spectrum of the z(sub em) = 1.052 radio-quiet quasar PG 2302+029. Broad absorption with FWHM from 3000 to 5000 km/s is detected from C iv, N v, and O vi in Hubble Space Telescope (HST) Faint Object Spectrograph spectra of the quasar. A narrow-line system (FWHM approx. 250 km/s) at z(sub abs) = 0.7016 is resolved from the broad blend and includes absorption by Ly alpha and the C iv, N v, and O vi doublets. No absorption by low-ionization metal species (e.g., Si II and Mg II) is detected in the HST or ground-based spectra for either the broad or the narrow system. The centroids of the broad system lines are displaced by approx. 56,000 km/s to the blue of the quasar's broad emission lines. The reddest extent of the broad-line absorption is more than 50,000 km/s from the quasar. The properties of this system are unprecedented, whether it is an intervening or an ejected system.

  9. Scalar currents in 0(+) going to 0(+) beta decay and the boron-8 neutrino spectrum

    NASA Astrophysics Data System (ADS)

    Ortiz, Chris Eduardo

    2000-07-01

    Two experiments to understand the standard electro-weak model are presented. In one experiment scalar contributions to the weak interaction were searched for by determining with accuracy the e - ν correlation coefficient in a 0+ --> 0+ decay. The correlation coefficient for the 0+ --> 0+ β-decay of 32Ar was measured to be a = 0.9989 +/- 0.0052 +/- 0.0036, for vanishing Fierz interference. This was used to put unprecedented limits on scalar contributions to the weak interaction. In the second experiment the β-delayed α spectrum from 8B was measured. The experiment was designed to overcome systematic uncertainties that plagued previous measurements. This spectrum differs significantly from previous measurements. The measured α spectrum was used to deduce the ν spectrum. This will be used as a benchmark by experiments trying to detect distortions of the solar-ν spectrum in the search for physics beyond the standard model.

  10. The Milky Way's Hot Gas Kinematics: Signatures in Current and Future OVII Absorption Line Observations

    NASA Astrophysics Data System (ADS)

    Miller, Matthew J.; Hodges-Kluck, Edmund J.; Bregman, Joel N.

    2016-02-01

    Detections of z ≈ 0 oxygen absorption and emission lines indicate the Milky Way hosts a hot (˜ {10}6 K), low-density plasma extending ≳ 50 {{kpc}} into the Mily Way’s halo. Current X-ray telescopes cannot resolve the line profiles, but the variation of their strengths on the sky constrains the radial gas distribution. Interpreting the O vii Kα absorption line strengths has several complications, including optical depth and line of sight velocity effects. Here, we present model absorption line profiles accounting for both of these effects to show the lines can exhibit asymmetric structures and be broader than the intrinsic Doppler width. The line profiles encode the hot gas rotation curve, the net inflow or outflow of hot gas, and the hot gas angular momentum profile. We show how line of sight velocity effects impact the conversion between equivalent width and the column density, and provide modified curves of growth accounting for these effects. As an example, we analyze the LMC sight line pulsar dispersion measure and O vii equivalent width to show the average gas metallicity is ≳ 0.6{Z}⊙ and b ≳ 100 km s-1. Determining these properties offers valuable insights into the dynamical state of the Milky Way’s hot gas, and improves the line strength interpretation. We discuss future strategies to observe these effects with an instrument that has a spectral resolution of about 3000, a goal that is technically possible today.

  11. On the variations of O III forbidden line intensities in the spectrum of the planetary nebula IC 4997

    NASA Astrophysics Data System (ADS)

    Egikyan, A. G.

    1997-10-01

    The causes of asynchronous variations in the intensities of forbidden O III lines in the spectrum of the planetary nebula IC 4997 are considered. It is shown that the strengthening of the 4363-A line with a simultaneous weakening of the N1 and N2 lines can be explained by a severalfold increase of the mass-loss rate from the nucleus, up to 1-2 x 10 exp -7 solar mass/yr, over several years. The ionization model of the nebula under the combined effect of nucleus emission and the emission from a variable hot stellar wind with electron temperature of 500,000 K is used to calculate the theoretical line intensities. The calculations included 12 levels of O III. In the region of O III line formation, the electron density of 10 exp 6/cu cm and Te, which varies from 12,000 to 15,000 K, yield theoretical line intensities that are in best agreement with observations. The X-ray luminosity of the stellar wind from the nucleus at energies not less than 0.2 keV is on the order of 10 exp 35 erg/s, but the interstellar extinction rules out the possibility of observing this object.

  12. Compact steep-spectrum sources as the parent population of flat-spectrum radio-loud narrow-line Seyfert 1 galaxies

    NASA Astrophysics Data System (ADS)

    Berton, M.; Caccianiga, A.; Foschini, L.; Peterson, B. M.; Mathur, S.; Terreran, G.; Ciroi, S.; Congiu, E.; Cracco, V.; Frezzato, M.; La Mura, G.; Rafanelli, P.

    2016-06-01

    Narrow-line Seyfert 1 galaxies (NLS1s) are an interesting subclass of active galactic nuclei (AGN), which tipically does not exhibit any strong radio emission. Seven percent of them, though, are radio-loud and often show a flat radio-spectrum (F-NLS1s). This, along to the detection of γ-ray emission coming from them, is usually interpreted as a sign of a relativistic beamed jet oriented along the line of sight. An important aspect of these AGN that must be understood is the nature of their parent population, in other words how do they appear when observed under different angles. In the recent literature it has been proposed that a specific class of radio-galaxies, compact-steep sources (CSS) classified as high excitation radio galaxies (HERG), can represent the parent population of F-NLS1s. To test this hypothesis in a quantitative way,in this paper we analyzed the only two statistically complete samples of CSS/HERGs and F-NLS1s available in the literature. We derived the black hole mass and Eddington ratio distributions, and we built for the first time the radio luminosity function of F-NLS1s. Finally, we applied a relativistic beaming model to the luminosity function of CSS/HERGs, and compared the result with the observed function of F-NLS1s. We found that compact steep-spectrum sources are valid parent candidates and that F-NLS1s, when observed with a different inclination, might actually appear as CSS/HERGs.

  13. Discovery of iron line emission in the Hercules X-1 low state spectrum with HEAO-1

    NASA Technical Reports Server (NTRS)

    Pravdo, S. H.; Boldt, E. A.; Holt, S. S.; Rothschild, R. E.; Serlemitsos, P. J.

    1978-01-01

    The line energy, equivalent width, binary phase dependence, and intrinsic width of the iron line emission feature observed in the low state sepctrum of Hercules X-1 are examined. Deductions are made concerning secondary X-ray emission from this binary system.

  14. Current singularities in line-tied three-dimensional magnetic fields

    SciTech Connect

    Craig, I. J. D.; Pontin, D. I. E-mail: dpontin@maths.dundee.ac.uk

    2014-06-20

    This paper considers the current distributions that derive from finite amplitude perturbations of line-tied magnetic fields comprising hyperbolic field structures. The initial equilibrium on which we principally focus is a planar magnetic X-point threaded by a uniform axial field. This field is line-tied on all surfaces but subject to three-dimensional (3D) disturbances that alter the initial topology. Results of ideal relaxation simulations are presented which illustrate how intense current structures form that can be related, through the influence of line-tying, to the quasi-separatrix layers (QSLs) of the initial configuration. It is demonstrated that the location within the QSL that attracts the current, and its scaling properties, are strongly dependent on the relative dimensions of the QSL with respect to the line-tied boundaries. These results are contrasted with the behavior of a line-tied 3D field containing an isolated null point. In this case, it is found that the dominant current always forms at the null, but that the collapse is inhibited when the null is closer to a line-tied boundary.

  15. First identification of pure rotation lines of NH in the infrared solar spectrum

    NASA Technical Reports Server (NTRS)

    Geller, M.; Farmer, C. B.; Norton, R. H.; Sauval, A. J.; Grevesse, N.

    1991-01-01

    Pure rotation lines of NH of the v = 0 level and v = 1 level are detected in high-resolution solar spectra obtained from the Atmospheric Trace Molecule Spectroscopy (ATMOS) experimental observations. It is pointed out that the identification of the lines is favored by the typical appearance of the triplet lines of nearly equal intensities. The observed equivalent widths of these triplet lines are compared with predicted intensities, and it is observed that these widths are systematically larger than the predicted values. It is noted that because these very faint lines are observed in a region where the signal is very low, a systematic error in the measurements of the equivalent widths cannot be ruled out; therefore, the disagreement between the observed and predicted intensities is not considered to be real.

  16. Fast thermonuclear ignition with two nested high current lower voltage - high voltage lower current magnetically insulated transmission lines

    NASA Astrophysics Data System (ADS)

    Winterberg, F.

    2003-11-01

    Fast thermonuclear ignition with a high gain seems possible with two Marx generators feeding two nested magnetically insulated transmission lines, one delivering a high current lower voltage pulse for compression and confinement, and one delivering a high voltage lower current pulse for fast ignition. With an input energy conceivably as small as 100 kJ the gain can be as large as 10 3. The concept not only would be by orders of magnitude less expensive than laser compression and fast ignition schemes, but because of the large gain with a small yield also be more suitable for a thermonuclear reactor.

  17. Development of Fault Point Locating System for Underground Transmission Lines using Optical Fiber Current Sensors

    NASA Astrophysics Data System (ADS)

    Kurosawa, Kiyoshi; Kondo, Reishi; Nasukawa, Shinsuke; Yamaguchi, Tatsushi; Amano, Kazuo

    Fault point locating systems based on surge current detection have recently been used for fast recovery of underground transmission line from the fault. Electromagnetic induction type sensors have mainly been used for detection of the surge current. However they are susceptible to electromagnetic noise which causes unstable system operation. To solve this problem, Tokyo Electric Power Co., Toko Electric Corporation and Fujikura Ltd., by a joint research, have developed a new system that applies optical fiber current sensors.

  18. A search for TiO in the optical high-resolution transmission spectrum of HD 209458b: Hindrance due to inaccuracies in the line database

    NASA Astrophysics Data System (ADS)

    Hoeijmakers, H. J.; de Kok, R. J.; Snellen, I. A. G.; Brogi, M.; Birkby, J. L.; Schwarz, H.

    2015-03-01

    Context. The spectral signature of an exoplanet can be separated from the spectrum of its host star using high-resolution spectroscopy. During these observations, the radial component of the planet's orbital velocity changes, resulting in a significant Doppler shift that allows its spectral features to be extracted. Aims: In this work, we aim to detect TiO in the optical transmission spectrum of HD 209458b. Gaseous TiO has been suggested as the cause of the thermal inversion layer invoked to explain the dayside spectrum of this planet. Methods: We used archival data from the 8.2 m Subaru telescope taken with the High Dispersion Spectrograph of a transit of HD 209458b in 2002. We created model transmission spectra that include absorption by TiO, and cross-correlated them with the residual spectral data after removal of the dominating stellar absorption features. We subsequently co-added the correlation signal in time, taking the change in Doppler shift due to the orbit of the planet into account. Results: We detect no significant cross-correlation signal due to TiO, though artificial injection of our template spectra into the data indicates a sensitivity down to a volume-mixing ratio of ~10-10. However, cross-correlating the template spectra with a HARPS spectrum of Barnard's star yields only a weak wavelength-dependent correlation, even though Barnard's star is an M4V dwarf that exhibits clear TiO absorption. We infer that the TiO line list poorly matches the real positions of TiO lines at spectral resolutions of ~100 000. Similar line lists are also used in the PHOENIX and Kurucz stellar atmosphere suites and we show that their synthetic M-dwarf spectra also correlate poorly with the HARPS spectra of Barnard's star and five other M dwarfs. We conclude that the lack of an accurate TiO line list is currently critically hampering this high-resolution retrieval technique.

  19. Spectral analysis of R-lines and vibronic sidebands in the emission spectrum of ruby using genetic algorithms.

    PubMed

    Raghavan, Seetha; Imbrie, P K; Crossley, William A

    2008-07-01

    The advancement in spectral analysis methods for the emission spectrum of ruby has been driven by the characterization of R-line peak shifts with stress in order to establish piezospectroscopic relationships. These relationships form the basis for the development of photo-stimulated luminescence spectroscopy (PSLS) as a nondestructive method to determine the integrity of the thermally grown oxide (TGO) layer on jet engine turbine blades. Besides the measurement technique, the accuracy of PSLS in stress measurements is influenced by the spectral analysis methodology, which is the focus of this paper. Gradient-based algorithms have been used widely in the methods developed thus far. The approach of using genetic algorithms in the spectral analysis of R-lines and vibronic bands is presented here for the first time and validated with the wellknown piezospectroscopic coefficients of the R-lines. The implementation of this method has led to significant new results in the quantification of peak shifts with uniaxial stress in the vibronic bands of the spectrum. The use of genetic algorithms is instrumental in the deconvolution and fitting of the numerous peaks in these bands. Fitting statistics, such as the fitness function and number of function evaluations, were used to assess the effectiveness of the procedures used in this method. PMID:18935825

  20. Far-infrared line observations of planetary nebulae. 1: The O 3 spectrum

    NASA Technical Reports Server (NTRS)

    Dinerstein, H. L.; Lester, D. F.; Werner, M. W.

    1985-01-01

    Observations of the far-infrared fine structure lines of O III have been obtained for six planetary nebulae. The infrared measurements are combined with optical O III line fluxes to probe physical conditions in the gas. From the observed line intensity ratios, a simultaneous solution was obtained for electron temperature and density, as well as means of evaluating the importance of inhomogeneities. Densities determined from the far-infrared O III lines agree well density diagnostics from other ions, indicating a fairly homogeneous density in the emitting gas. Temperatures are determined separately from the O III 4363/5007 A and 5007 A/52 micron intensity ratios and compared. Systematically higher values are derived from the former ratio, which is expected from a nebula which is not isothermal. Allowance for the presence of temperature variations within these nebulae raises their derived oxygen abundances, determinations to be reconciled with the solar value.

  1. Far-infrared line observations of planetary nebulae. I - The forbidden O III spectrum

    NASA Astrophysics Data System (ADS)

    Dinerstein, H. L.; Lester, D. F.; Werner, M. W.

    1985-04-01

    Observations of the far-infrared fine structure lines of O III have been obtained for six planetary nebulae. The infrared measurements are combined with optical O III line fluxes to probe physical conditions in the gas. From the observed line intensity ratios, a simultaneous solution was obtained for electron temperature and density, as well as means of evaluating the importance of inhomogeneities. Densities determined from the far-infrared O III lines agree well with density diagnostics from other ions, indicating a fairly homogeneous density in the emitting gas. Temperatures are determined separately from the O III 4363/5007 A and 5007 A/52 micron intensity ratios and compared. Systematically higher values are derived from the former ratio, which is expected from a nebula which is not isothermal. Allowance for the presence of temperature variations within these nebulae raises their derived oxygen abundances, determinations to be reconciled with the solar value.

  2. Second-line treatment of metastatic gastric cancer: Current options and future directions

    PubMed Central

    Kanagavel, Dheepak; Fedyanin, Mikhail; Tryakin, Alexey; Tjulandin, Sergei

    2015-01-01

    Gastric cancer remains one among the leading causes of cancer-related deaths, regardless of its decreasing incidence and newly available treatment options. Most patients present at an advanced stage and are treated with upfront systemic chemotherapy. Those patients receiving first-line therapy may initially respond to treatment, but many of them relapse over time. In such condition, second-line treatment for disease progression remains the only available option. Although there exists no standard approach in the second-line setting, several phase III trials have shown modest survival benefit in patients receiving irinotecan, taxane and ramucirumab over the best supportive care or active agents. This review analyzes the currently available treatment regimens and future directions of research in the second-line setting for metastatic gastric cancer with the best available evidence. Additionally, the prognostic factors that influence patient survival in those receiving second-line therapy are discussed. PMID:26556991

  3. A new calculation of the cosmic-ray antiproton spectrum in the Galaxy and heliospheric modulation effects on this spectrum using a drift plus wavy current sheet model

    NASA Technical Reports Server (NTRS)

    Webber, W. R.; Potgieter, M. S.

    1989-01-01

    The expected interstellar antiproton spectrum arising from cosmic-ray interactions in the Galaxy is recalculated, and the modulation of both antiprotons and protons is calculated using a two-dimensional modulation model incorporating gradient and curvature drifts and a wavy current sheet as well as the usual diffusion, convection, and energy-loss effects. Significant differences in the antiproton/proton ratio for different solar magnetic field polarities are predicted as well as a 'low-energy' component for antiprotons below about 1 GeV.

  4. Behavioural methods used in rodent models of autism spectrum disorders: current standards and new developments.

    PubMed

    Wöhr, Markus; Scattoni, Maria Luisa

    2013-08-15

    Autism is a behaviourally defined disorder including attenuated or abnormal social interaction and communication, as well as aberrant repetitive behaviour, with symptoms emerging early in childhood. Although the cause of autism has not been discovered, several data strongly support the role of genetic factors in autism aetiology. For this reason, preclinical research is now focusing on generating transgenic and knockout mice, and more recently also rats, with mutations in genes identified in autistic children, with the main aim of understanding the role of those genes in autism aetiology, discovering the biological mechanisms underlying autistic behaviours detected in these mutant lines and evaluating potential treatments. Over the last years, a huge number of behavioural phenotyping assays for rodent models of autism and related disorders have been designed. In the first part of our review, we focus on current standards, i.e. state-of-the-art behavioural phenotyping tasks to assess autism core symptoms in rodent models. The second part is devoted to some few, in our view, very promising examples of new developments, namely an autism severity score, scent marking behaviour as an additional, ethologically valid measure for communication, plus a number of new developments in the behavioural domains of social facilitation, observational learning, and empathy. Finally, we will highlight the huge potential impact of newly generated rat knockout models of autism. PMID:23769995

  5. Suppression of parasitic currents on feed lines of colinear dual antenna systems

    SciTech Connect

    Campbell, D.V.; Fich, S.; Schwering, F.K.

    1980-09-01

    Investigations are reported of an antenna system consisting of a pair of colinear dipoles with a feed line isolator section which provides independent operation ofl the dipoles over an octave frequency range. The isolator section acts as a band elimination filter for the parasitic currents induced on the outer surface of the transmission line of the upper dipole. Suppression of these currents elimiates distortion of the antenna radiation patterns and significantly reduces coupling between the dipoles. Over the 200 to 400 MHz range, an interdipole isolation greater than 35 dB has been achieved between the colinear dipoles separated by 1.5 m.

  6. Study of spread spectrum multiple access systems for satellite communications with overlay on current services

    NASA Technical Reports Server (NTRS)

    Ha, Tri T.; Pratt, Timothy

    1989-01-01

    The feasibility of using spread spectrum techniques to provide a low-cost multiple access system for a very large number of low data terminals was investigated. Two applications of spread spectrum technology to very small aperture terminal (VSAT) satellite communication networks are presented. Two spread spectrum multiple access systems which use a form of noncoherent M-ary FSK (MFSK) as the primary modulation are described and the throughput analyzed. The analysis considers such factors as satellite power constraints and adjacent satellite interference. Also considered is the effect of on-board processing on the multiple access efficiency and the feasibility of overlaying low data rate spread spectrum signals on existing satellite traffic as a form of frequency reuse is investigated. The use of chirp is examined for spread spectrum communications. In a chirp communication system, each data bit is converted into one or more up or down sweeps of frequency, which spread the RF energy across a broad range of frequencies. Several different forms of chirp communication systems are considered, and a multiple-chirp coded system is proposed for overlay service. The mutual interference problem is examined in detail and a performance analysis undertaken for the case of a chirp data channel overlaid on a video channel.

  7. ExoMol molecular line lists - XIV: The rotation-vibration spectrum of hot SO2

    NASA Astrophysics Data System (ADS)

    Underwood, Daniel S.; Tennyson, Jonathan; Yurchenko, Sergei N.; Huang, Xinchuan; Schwenke, David W.; Lee, Timothy J.; Clausen, Sønnik; Fateev, Alexander

    2016-04-01

    Sulphur dioxide is well-known in the atmospheres of planets and satellites, where its presence is often associated with volcanism, and in circumstellar envelopes of young and evolved stars as well as the interstellar medium. This work presents a line list of 1.3 billion 32S16O2 vibration-rotation transitions computed using an empirically-adjusted potential energy surface and an ab initio dipole moment surface. The list gives complete coverage up to 8000 cm-1 (wavelengths longer than 1.25 μm) for temperatures below 2000 K. Infrared absorption cross sections are recorded at 300 and 500 C are used to validated the resulting ExoAmes line list. The line list is made available in electronic form as supplementary data to this article and at www.exomol.com.

  8. The second spectrum of niobium: III. Evaluation of line isotope shifts

    NASA Astrophysics Data System (ADS)

    Bouazza, Safa

    2013-03-01

    Using isotope shift values of only one Nb II line, we propose for the first time to predict isotope shifts of all spectral lines for this ion for any pair of isotopes. For this purpose, we had recourse to ab intio calculations to determine specific mass and field shifts of all relevant Nb II configuration averages, which are respectively proportional to the Vinti integral k-factor and the charge density at the nucleus, 4л|Ψ(o)|2. With the help of very accurate level eigenvectors of these configurations and using the sharing rule, we computed specific mass and field shifts of each level. Since a transition wavenumber is the difference between two energy levels, we then deduced line isotope shifts.

  9. ExoMol molecular line lists - XIV. The rotation-vibration spectrum of hot SO2

    NASA Astrophysics Data System (ADS)

    Underwood, Daniel S.; Tennyson, Jonathan; Yurchenko, Sergei N.; Huang, Xinchuan; Schwenke, David W.; Lee, Timothy J.; Clausen, Sønnik; Fateev, Alexander

    2016-07-01

    Sulphur dioxide is well-known in the atmospheres of planets and satellites, where its presence is often associated with volcanism, and in circumstellar envelopes of young and evolved stars as well as the interstellar medium. This work presents a line list of 1.3 billion 32S16O2 vibration-rotation transitions computed using an empirically adjusted potential energy surface and an ab initio dipole moment surface. The list gives complete coverage up to 8000 cm-1 (wavelengths longer than 1.25 μm) for temperatures below 2000 K. Infrared absorption cross-sections are recorded at 300 and 500 C are used to validated the resulting ExoAmes line list. The line list is made available in electronic form as supplementary data to this article and at www.exomol.com.

  10. Observations of plasma line splitting in the ionospheric incoherent scatter spectrum.

    PubMed

    Bhatt, Asti N; Nicolls, Michael J; Sulzer, Michael P; Kelley, Michael C

    2008-02-01

    Wide-bandwidth ionospheric incoherent scatter (IS) spectra obtained using the Arecibo IS radar show the occurrence of a split in the plasma line (i.e., two plasma lines) when the plasma frequency is close to the second harmonic of the electron gyrofrequency. This split is predicted in the IS theory for a magnetized plasma, but observations have never been reported. Here we present the experimental results and theoretical calculations supporting the observations. These results may assist in understanding the behavior of Langmuir waves in the magnetized plasma and are a validation of what historically was a somewhat controversial aspect of the IS theory. PMID:18352291

  11. Ultraviolet carbon lines in the spectrum of the white dwarf BPM 11668

    NASA Technical Reports Server (NTRS)

    Wegner, G.

    1983-01-01

    The southern hemisphere DC white dwarf BPM 11668 has been found to show strong ultraviolet lines of neutral carbon using observations from the IUE satellite. This star seems typical of the growing number of DC white dwarfs found to be of this type and appears to have a carbon abundance near C:He = 0.0001, with an effective temperature of 8500 K.

  12. A new interpretation of the meaning of the center of line slope from a two-dimensional infrared spectrum

    NASA Astrophysics Data System (ADS)

    Falvo, Cyril

    2016-06-01

    This article presents a new approximation to understand the connection between the center of line slope from a single peak of a two-dimensional (2D) infrared spectrum and the frequency-frequency correlation function. This approximation which goes beyond the short-time approximation includes explicitly pure dephasing mechanisms by introducing a time parameter that separates the fast fluctuations and slow fluctuations. While in the short-time approximation, the center of line slope is given by the normalized frequency fluctuations auto-correlation function, I show using this new approximation that the center of line slope measures on long time scales a shifted and scaled correlation function. The results present a new interpretation of the meaning of the center of line slope that allows for a better understanding of what 2D experiments can measure. To illustrate these findings, I compare this approximation with the short-time approximation for several examples of frequency-frequency correlation functions. I also give an estimate of the value of the time separation parameter for a correlation function with a simple exponential decay.

  13. A new interpretation of the meaning of the center of line slope from a two-dimensional infrared spectrum.

    PubMed

    Falvo, Cyril

    2016-06-21

    This article presents a new approximation to understand the connection between the center of line slope from a single peak of a two-dimensional (2D) infrared spectrum and the frequency-frequency correlation function. This approximation which goes beyond the short-time approximation includes explicitly pure dephasing mechanisms by introducing a time parameter that separates the fast fluctuations and slow fluctuations. While in the short-time approximation, the center of line slope is given by the normalized frequency fluctuations auto-correlation function, I show using this new approximation that the center of line slope measures on long time scales a shifted and scaled correlation function. The results present a new interpretation of the meaning of the center of line slope that allows for a better understanding of what 2D experiments can measure. To illustrate these findings, I compare this approximation with the short-time approximation for several examples of frequency-frequency correlation functions. I also give an estimate of the value of the time separation parameter for a correlation function with a simple exponential decay. PMID:27334150

  14. Simulation of the behavior of superconducting YBCO lines at high current densities

    NASA Astrophysics Data System (ADS)

    Antognazza, L.; Decroux, M.; Reymond, S.; de Chambrier, E.; Triscone, J.-M.; Paul, W.; Chen, M.; Fischer, Ø.

    2002-08-01

    We report on the behavior of YBCO lines at high current densities. The experiments are performed, with short constant current pulses, on Au/YBCO/CeO 2 structures grown on 2″ sapphire wafers. We found that a quasi spontaneous highly dissipative state (HDS) appears at a critical current J*, which is also temperature dependent. The initial propagation velocity of the HDS can reach values as high as 150 m/s for a current of 3 Jc. We show experimental evidences that this HDS is driven by the current and does not originate from a thermal runaway of the superconducting line. To confirm these results, we have simulated the thermal behavior of the line, using a calculation based on a finite element method, including the dissipation coming from the flux flow. This model reproduces very well the propagation velocity, and its current dependence, observed experimentally if we include the temperature dependence of J*, whereas the calculated velocities in the case of a purely thermal runaway are one order of magnitude lower.

  15. Temperature and strain measurements using the power, line-width, shape, and frequency shift of the Brillouin loss spectrum

    NASA Astrophysics Data System (ADS)

    Bao, Xiaoyi; Smith, Jeffrey; Brown, Anthony W.

    2002-09-01

    A Brillouin scattering based fiber sensor system has been developed by our Fiber Optics Group for the structural monitoring and civil engineering related applications. In this paper, the Brillouin loss spectrum has been characterized in terms of its center frequency, peak power, line-width and shape. These parameters have been considered as a function of the input pump and probe laser powers, the pump pulse duration, strain and temperature. The measurement accuracy has been studied at different Brillouin frequency steps to study the uncertainty of the Brillouin frequency, line-width, peak power and shape factor vs. signal to noise ratio, so that we can optimize the system performance. Characterization of the Brillouin loss spectrum led to the development of an innovative technique to measure the strain and temperature simultaneously using the strain and temperature dependence on the peak power in conjunction with the Brillouin frequency for the single mode fiber with 3m spatial resolution, 3°C temperature resolution and 200 me (mm/m) strain accuracy.

  16. Current densities and total contact currents during forest clearing tasks under 400 kV power lines.

    PubMed

    Korpinen, Leena; Kuisti, Harri; Elovaara, Jarmo

    2016-09-01

    The aim of the study was to analyze all values of electric currents from measured periods while performing tasks in forest clearing. The objective was also to choose and analyze measurement cases, where current measurements successfully lasted the entire work period (about 30 min). Two forestry workers volunteered to perform four forest clearing tasks under 400 kV power lines. The sampling frequency of the current measurements was 1 sample/s. The maximum values of the current densities were 1.0-1.2 mA/m(2) (calculated internal EFs 5.0-12.0 mV/m), and the average values were 0.2-0.4 mA/m(2) . The highest contact current was 167.4 μA. All measured values during forest clearing tasks were lower than basic restrictions (0.1 V/m and 0.8 V/m) of the International Commission on Non-Ionizing Radiation Protection. Bioelectromagnetics. 37:423-428, 2016. © 2016 The Authors. Bioelectromagnetics published by Wiley Periodicals, Inc. PMID:27192179

  17. Field line twist and field-aligned currents in an axially symmetric equilibrium magnetosphere. [of Uranus

    NASA Technical Reports Server (NTRS)

    Voigt, Gerd-Hannes

    1986-01-01

    Field-aligned Birkeland currents and the angle of the magnetic line twist were calculated for an axially symmetric pole-on magnetosphere (assumed to be in MHD equilibrium). The angle of the field line twist was shown to have a strong radial dependence on the axisymmetric magnetotail as well as on the ionospheric conductivity and the amount of thermal plasma contained in closed magnetotail flux tubes. The field line twist results from the planetary rotation, which leads to the development of a toroidal magnetic B-sub-phi component and to differentially rotating magnetic field lines. It was shown that the time development of the toroidal magnetic B-sub-phi component and the rotation frequency are related through an induction equation.

  18. Informing Children about Their Sibling's Diagnosis of Autism Spectrum Disorder: An Initial Investigation into Current Practices

    ERIC Educational Resources Information Center

    Tanaka, Kyoko; Uchiyama, Tokio; Endo, Fumio

    2011-01-01

    The manner in which typically developing (TD) children were informed about their sibling's diagnosis of autism spectrum disorders (ASDs) was examined in Japan. Seventy-seven parents, each with a child with ASD and a TD child, participated in a questionnaire survey. From the data obtained, it was revealed that parents informed 66.7% (72/108) TD…

  19. Current Practice in Psychopharmacology for Children and Adolescents with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Floyd, Elizabeth Freeman; McIntosh, David E.

    2009-01-01

    Autism spectrum disorders (ASDs) are a complex group of neurodevelopmental conditions that develop in early childhood and involve a range of impairments in core areas of social interaction, communication, and restricted behavior and interests. Associated behavioral problems such as tantrums, aggression, and self-injury frequently compound the core…

  20. Magnetic field line reconnection experiments. V - Current disruptions and double layers

    NASA Technical Reports Server (NTRS)

    Stenzel, R. L.; Gekelman, W.; Wild, N.

    1983-01-01

    An investigation is conducted of the stability of a large laboratory plasma current sheet, which has been generated in the process of magnetic field line reconnection, with respect to local current increases. Magnetic flux variations in regions remote from the current sheet generate an inductive voltage in the current loop that drops off inside the plasma in the form of a potential double layer, leading to particle acceleration with velocities much larger than those expected from the steady state electric fields in the plasma. A model for the mechanism of the current disruptions is formulated in which the potential structure leads to ion expulsion, creating a localized density drop. The associated current drop in an inductive circuit drives the potential structure, providing feedback for the disruptive instability. Similarities to, and differences from, magnetospheric substorm phenomena are noted.

  1. SUBMILLIMETER LINE SPECTRUM OF THE SEYFERT GALAXY NGC 1068 FROM THE HERSCHEL-SPIRE FOURIER TRANSFORM SPECTROMETER

    SciTech Connect

    Spinoglio, Luigi; Pereira-Santaella, Miguel; Busquet, Gemma; Schirm, Maximilien R. P.; Wilson, Christine D.; Parkin, Tara J.; Glenn, Jason; Kamenetzky, Julia; Rangwala, Naseem; Maloney, Philip R.; Bendo, George J.; Madden, Suzanne C.; Boselli, Alessandro; Cooray, Asantha; Page, Mathew J.

    2012-10-20

    The first complete submillimeter spectrum (190-670 {mu}m) of the Seyfert 2 galaxy NGC 1068 has been observed with the SPIRE Fourier transform spectrometer on board the Herschel Space Observatory. The sequence of CO lines (J {sub up} = 4-13), lines from H{sub 2}O, the fundamental rotational transition of hydrogen fluoride, two o-H{sub 2}O{sup +} lines, and one line each from CH{sup +} and OH{sup +} have been detected, together with the two [C I] lines and the [N II] 205 {mu}m line. The observations in both single pointing mode with sparse image sampling and in mapping mode with full image sampling allow us to disentangle two molecular emission components, one due to the compact circumnuclear disk (CND) and one from the extended region encompassing the star-forming ring (SF-ring). Radiative transfer models show that the two CO components are characterized by densities of n(H{sub 2}) = 10{sup 4.5} and 10{sup 2.9} cm{sup -3} and temperatures of T {sub kin} = 100 K and 127 K, respectively. A comparison of the CO line intensities with the photodissociation region (PDR) and X-ray-dominated region (XDR) models, together with the other observational constraints, such as the observed CO surface brightness and the radiation field, indicates that the best explanation for the CO excitation of the CND is an XDR with a density of n(H{sub 2}) {approx} 10{sup 4} cm{sup -3} and an X-ray flux of 9 erg s{sup -1} cm{sup -2}, consistent with illumination by the active galactic nucleus, while the CO lines in the SF-ring are better modeled by a PDR. The detected water transitions, together with those observed with the Herschel PACS spectrometer, can be modeled by a large velocity gradient model with low temperature (T {sub kin} {approx} 40 K) and high density (n(H{sub 2}) in the range 10{sup 6.7}-10{sup 7.9} cm{sup -3}). The emission of H{sub 2}O{sup +} and OH{sup +} are in agreement with PDR models with cosmic-ray ionization. The diffuse ionized atomic component observed through the [N

  2. Spectrum of hot methane in astronomical objects using a comprehensive computed line list

    PubMed Central

    Yurchenko, Sergei N.; Tennyson, Jonathan; Bailey, Jeremy; Hollis, Morgan D. J.; Tinetti, Giovanna

    2014-01-01

    Hot methane spectra are important in environments ranging from flames to the atmospheres of cool stars and exoplanets. A new spectroscopic line list, 10to10, for 12CH4 containing almost 10 billion transitions is presented. This comprehensive line list covers a broad spectroscopic range and is applicable for temperatures up to 1,500 K. Previous methane data are incomplete, leading to underestimated opacities at short wavelengths and elevated temperatures. Use of 10to10 in models of the bright T4.5 brown dwarf 2MASS 0559-14 leads to significantly better agreement with observations and in studies of the hot Jupiter exoplanet HD 189733b leads to up to a 20-fold increase in methane abundance. It is demonstrated that proper inclusion of the huge increase in hot transitions which are important at elevated temperatures is crucial for accurate characterizations of atmospheres of brown dwarfs and exoplanets, especially when observed in the near-infrared. PMID:24979770

  3. Cas A X-ray spectrum: Evidence for iron line emission

    NASA Technical Reports Server (NTRS)

    Serlemitsos, P. J.; Boldt, E. A.; Holt, S. S.; Ramaty, R.; Brisken, A. F.

    1973-01-01

    A sensitive measurement by rocket borne detectors of the X-ray flux from Cas A has revealed a steep continuum and a broad spectral feature in the region where line radiation from iron nuclei would be expected. The flux in this feature is .0122 plus or minus .0017 photons/sq cm/s: the total energy flux from 2 to 10 KeV is 1.02 x 10 to the minus 9th power ergs/sq cm/s. The presence of broad iron lines is consistent with a model in which approximately 13 MeV/nucleon iron nuclei charge exchange with surrounding interstellar oxygen and other heavy atoms. The model suggests that a substantial fraction of the energy from the outburst has gone into low energy cosmic rays which produce the observed HII region surrounding the remnant.

  4. Atmospheric 60-GHz oxygen spectrum - New laboratory measurements and line parameters

    NASA Astrophysics Data System (ADS)

    Liebe, H. J.; Rosenkranz, P. W.; Hufford, G. A.

    1992-12-01

    Over 5000 absolute absorption values for pressure-broadened O2 lines in dry air were measured at frequencies from 49 to 67 GHz in 0.1-GHz-increments. The controlled laboratory studies were carried out at three temperatures (6, 30, and 54 C) for 11 pressure values ranging between 1.3 and 101 kPa. The spectrometer consisted of a Fabry-Perot resonator combined with an automatic network analyzer. The detection sensitivity was better than +/- 0.02 dB/km, and measurement uncertainties were estimated to be typically better than +/- 0.05 dB/km for attenuation rates below 3 dB/km, or better than +/- 2 percent for higher rates. The extensive data set was compared with predictions by an established model (MPM89). Systematic discrepancies were recognized and reduced by means of a readjustment of line parameters. The new model (MPM92) is given here.

  5. Spectrum of hot methane in astronomical objects using a comprehensive computed line list.

    PubMed

    Yurchenko, Sergei N; Tennyson, Jonathan; Bailey, Jeremy; Hollis, Morgan D J; Tinetti, Giovanna

    2014-07-01

    Hot methane spectra are important in environments ranging from flames to the atmospheres of cool stars and exoplanets. A new spectroscopic line list, 10to10, for (12)CH4 containing almost 10 billion transitions is presented. This comprehensive line list covers a broad spectroscopic range and is applicable for temperatures up to 1,500 K. Previous methane data are incomplete, leading to underestimated opacities at short wavelengths and elevated temperatures. Use of 10to10 in models of the bright T4.5 brown dwarf 2MASS 0559-14 leads to significantly better agreement with observations and in studies of the hot Jupiter exoplanet HD 189733b leads to up to a 20-fold increase in methane abundance. It is demonstrated that proper inclusion of the huge increase in hot transitions which are important at elevated temperatures is crucial for accurate characterizations of atmospheres of brown dwarfs and exoplanets, especially when observed in the near-infrared. PMID:24979770

  6. The X-ray spectrum and time variability of narrow emission line galaxies

    NASA Technical Reports Server (NTRS)

    Mushotzky, R.

    1981-01-01

    X-ray spectral and temporal observations are reported for six narrow emission line galaxies (NELGs), all of which are fitted by power-law X-ray spectra of energy slope 0.8 and have column densities in the line of sight greater than 1 x 10 to the 22nd atoms/sq cm. Three of the objects, NGC 526a, NGC 2110 and MCG-5-23-16 are variable in their X-ray flux, and the latter two, along with NGC 5506 and NGC 7582, showed detectable variability in at least one observation. The measured X-ray properties of these NELGs, which also included NGC 2992, strongly resemble those of previously-measured type 1 Seyferts of the same X-ray luminosity and lead to the conclusion of great similarity between the NELGs and low-luminosity type 1 Seyferts. The implications of these observations for the optical line-emitting region structure of these galaxies are discussed.

  7. Wolf-Rayet Stellar Wind Instability: Very Rapid Variability of the Line Spectrum of HD 90657

    NASA Astrophysics Data System (ADS)

    Auer, Lawrence

    In our IUE observation of the WN+O6 binary system, HD 90657, changes in the spectrum were detected with a time scale shorter than 90 minutes (Koenigsberger and Auer 1987). The variation requires the existence of significant changes in the small scale structure of the wind. We propose to augment this result by observation of the system at four distinct orbital phases, using absorption of the O-star flux as a direct probe of the small scale wind structure. The data obtained will both give general information on the growth of wind instabilities and determine if they are periodio-an important constraint on their origin. We will also inspect the IUE archives for other evidence of short time scale variations in WR targets.

  8. Transmission line component testing for the ITER Ion Cyclotron Heating and Current Drive System

    NASA Astrophysics Data System (ADS)

    Goulding, Richard; Bell, G. L.; Deibele, C. E.; McCarthy, M. P.; Rasmussen, D. A.; Swain, D. W.; Barber, G. C.; Barbier, C. N.; Cambell, I. H.; Moon, R. L.; Pesavento, P. V.; Fredd, E.; Greenough, N.; Kung, C.

    2014-10-01

    High power RF testing is underway to evaluate transmission line components for the ITER Ion Cyclotron Heating and Current Drive System. The transmission line has a characteristic impedance Z0 = 50 Ω and a nominal outer diameter of 305 mm. It is specified to carry up to 6 MW at VSWR = 1.5 for 3600 s pulses, with transient voltages up to 40 kV. The transmission line is actively cooled, with turbulent gas flow (N2) used to transfer heat from the inner to outer conductor, which is water cooled. High voltage and high current testing of components has been performed using resonant lines generating steady state voltages of 35 kV and transient voltages up to 60 kV. A resonant ring, which has operated with circulating power of 6 MW for 1 hr pulses, is being used to test high power, low VSWR operation. Components tested to date include gas barriers, straight sections of various lengths, and 90 degree elbows. Designs tested include gas barriers fabricated from quartz and aluminum nitride, and transmission lines with quartz and alumina inner conductor supports. The latest results will be presented. This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy.

  9. Evaluation of wet-line depth-correction methods for cable-suspended current meters

    USGS Publications Warehouse

    Coon, W.F.; Futrell, James C.

    1986-01-01

    Wet-line depth corrections for cable-suspended current meter and weight not perpendicular to the water surface have been evaluated using cable-suspended weights towed by a boat in still water. A fathometer was used to track a Columbus sounding weight and to record its actual depth for several apparent depths, weight sizes, and towed velocities. Cable strumming, tension, and weight veer are noted. Results of this study suggest possible differences between observed depth corrections and corrections obtained from the wet-line correction table currently in use. These differences may have resulted from test conditions which deviated from the inherent assumptions of the wet-line table: (1) drag on the weight in the sounding position at the bottom of a stream can be neglected; and (2) the distribution of horizontal drag on the sounding line is in accordance with the variation of velocity with depth. Observed depth corrections were compared to wet-line table values used for determining the 0.8-depth position of the sounding weight under these conditions; the results indicate that questionable differences exist. (Lantz-PTT)

  10. A Novel Transient Fault Current Sensor Based on the PCB Rogowski Coil for Overhead Transmission Lines.

    PubMed

    Liu, Yadong; Xie, Xiaolei; Hu, Yue; Qian, Yong; Sheng, Gehao; Jiang, Xiuchen

    2016-01-01

    The accurate detection of high-frequency transient fault currents in overhead transmission lines is the basis of malfunction detection and diagnosis. This paper proposes a novel differential winding printed circuit board (PCB) Rogowski coil for the detection of transient fault currents in overhead transmission lines. The interference mechanism of the sensor surrounding the overhead transmission line is analyzed and the guideline for the interference elimination is obtained, and then a differential winding printed circuit board (PCB) Rogowski coil is proposed, where the branch and return line of the PCB coil were designed to be strictly symmetrical by using a joining structure of two semi-rings and collinear twisted pair differential windings in each semi-ring. A serial test is conducted, including the frequency response, linearity, and anti-interference performance as well as a comparison with commercial sensors. Results show that a PCB Rogowski coil has good linearity and resistance to various external magnetic field interferences, thus enabling it to be widely applied in fault-current-collecting devices. PMID:27213402

  11. A Novel Transient Fault Current Sensor Based on the PCB Rogowski Coil for Overhead Transmission Lines

    PubMed Central

    Liu, Yadong; Xie, Xiaolei; Hu, Yue; Qian, Yong; Sheng, Gehao; Jiang, Xiuchen

    2016-01-01

    The accurate detection of high-frequency transient fault currents in overhead transmission lines is the basis of malfunction detection and diagnosis. This paper proposes a novel differential winding printed circuit board (PCB) Rogowski coil for the detection of transient fault currents in overhead transmission lines. The interference mechanism of the sensor surrounding the overhead transmission line is analyzed and the guideline for the interference elimination is obtained, and then a differential winding printed circuit board (PCB) Rogowski coil is proposed, where the branch and return line of the PCB coil were designed to be strictly symmetrical by using a joining structure of two semi-rings and collinear twisted pair differential windings in each semi-ring. A serial test is conducted, including the frequency response, linearity, and anti-interference performance as well as a comparison with commercial sensors. Results show that a PCB Rogowski coil has good linearity and resistance to various external magnetic field interferences, thus enabling it to be widely applied in fault-current-collecting devices. PMID:27213402

  12. ExoMol molecular line lists - XIII. The spectrum of CaO

    NASA Astrophysics Data System (ADS)

    Yurchenko, Sergei N.; Blissett, Audra; Asari, Usama; Vasilios, Marcus; Hill, Christian; Tennyson, Jonathan

    2016-03-01

    An accurate line list for calcium oxide is presented covering transitions between all bound ro-vibronic levels from the five lowest electronic states X 1Σ+, A' 1Π, A 1Σ+, a 3Π, and b 3Σ+. The ro-vibronic energies and corresponding wavefunctions were obtained by solving the fully coupled Schrödinger equation. Ab initio potential energy, spin-orbit, and electronic angular momentum curves were refined by fitting to the experimental frequencies and experimentally derived energies available in the literature. Using our refined model we could (1) reassign the vibronic states for a large portion of the experimentally derived energies (van Groenendael A., Tudorie M., Focsa C., Pinchemel B., Bernath P. F., 2005, J. Mol. Spectrosc., 234, 255), (2) extended this list of energies to J = 61-118 and (3) suggest a new description of the resonances from the A 1Σ+-X 1Σ+ system. We used high level ab initio electric dipole moments reported previously (Khalil H., Brites V., Le Quere F., Leonard C., 2011, Chem. Phys., 386, 50) to compute the Einstein A coefficients. Our work is the first fully coupled description of this system. Our line list is the most complete catalogue of spectroscopic transitions available for 40Ca16O and is applicable for temperatures up to at least 5000 K. CaO has yet to be observed astronomically but its transitions are characterized by being particularly strong which should facilitate its detection. The CaO line list is made available in an electronic form as supplementary data to this article and at www.exomol.com.

  13. The quantum interference effects in the SC II 4247 Å line of the second solar spectrum

    SciTech Connect

    Smitha, H. N.; Nagendra, K. N.; Stenflo, J. O.; Bianda, M.; Ramelli, R. E-mail: knn@iiap.res.in E-mail: mbianda@irsol.ch

    2014-10-10

    The Sc II 4247 Å line formed in the chromosphere is one of the lines well known, like the Na I D{sub 2} and Ba II D{sub 2}, for its prominent triple-peak structure in Q/I and the underlying quantum interference effects governing it. In this paper, we try to study the nature of this triple-peak structure using the theory of F-state interference including the effects of partial frequency redistribution (PRD) and radiative transfer (RT). We compare our results with the observations taken in a quiet region near the solar limb. In spite of accounting for PRD and RT effects, it has not been possible to reproduce the observed triple-peak structure in Q/I. While the two wing PRD peaks (on either side of central peak) and the near wing continuum can be reproduced, the central peak is completely suppressed by the enhanced depolarization resulting from the hyperfine structure splitting. This suppression remains for all the tested widely different one-dimensional model atmospheres or for any multi-component combinations of them. While multidimensional RT effects may improve the fit to the intensity profiles, they do not appear capable of explaining the enigmatic central Q/I peak. This leads us to suspect that some aspect of quantum physics is missing.

  14. Wavelet transform-based fault diagnosis and line selection method of small current grounding system

    NASA Astrophysics Data System (ADS)

    Yang, Ni; Zhang, Shuqing; Zhang, Liguo; Zhang, Kexin; Sun, Lingyun

    2008-12-01

    Small current grounding system is the system that the neutral point doesn't ground or grounds across the arc suppressing coils, which has been applied commonly in distribution system of many countries. As the grounding fault occurs, current is the one caused by capacity of circuit to ground only and it is rather small. The status of fault is complexity, e.g., the electromagnet interferes together with the amplified impact of zero-order loops to high-order singularity waves and various temporary variables. All these result in the lower ratio of the fault element signal to noise caused by zero-order current. In this paper, the position of signal singularity and the magnitude of the singularity degree are analyzed based on the variable focus character of wavelet, and the time fault occurs is then determined. The series db wavelet with close sustain is adopted, and the line selection is according to the zero-order voltage of the generatrix and the current of various outlet line. It is proved by the experiment that the fault circuit diagnosis method based on wavelet analysis to the character of temporary status of single-phase grounding fault plays an important role to a finer line selection.

  15. Spectroscopic Observations of Steep Spectrum Narrow-Line Seyfert 1 Galaxies

    NASA Technical Reports Server (NTRS)

    Leighly, Karen

    1999-01-01

    ROSAT observations of narrow-line Seyfert 1s found consistently steep spectra and rapid variability, but ASCA observations show more diversity, very different to classical Seyfert 1s. However, in 3 NLS1s, ASCA finds common characteristics of these exciting new class of AGN (active galactic nuclei): a very strong high temperature soft excess, weak hard tail, a possible blue shifted ionized oxygen edge, and rapid large amplitude variability characterized by flares and quiescent periods. It is necessary to observe many more such objects in order to understand the physical processes underlying the different phenomenology in ASCA. ASCA observations of two NLS1s discovered by ROSAT's all sky survey were proposed and an observation of one of these objects, RX J0439-45, was awarded. The results of spectral and variability analysis are included in Leighly 1999ab, and preliminary results are found in Leighly 1998ab.

  16. Alternating current line-filter based on electrochemical capacitor utilizing template-patterned graphene.

    PubMed

    Wu, Zhenkun; Li, Liyi; Lin, Ziyin; Song, Bo; Li, Zhuo; Moon, Kyoung-Sik; Wong, Ching-Ping; Bai, Shu-Lin

    2015-01-01

    Aluminum electrolytic capacitors (AECs) are widely used for alternating current (ac) line-filtering. However, their bulky size is becoming more and more incompatible with the rapid development of portable electronics. Here we report a scalable process to fabricate miniaturized graphene-based ac line-filters on flexible substrates at room temperature. In this work, graphene oxide (GO) is reduced by patterned metal interdigits at room temperature and used directly as the electrode material. The as-fabricated device shows a phase angle of -75.4° at 120 Hz with a specific capacitance of 316 µF/cm(2) and a RC time constant of 0.35 ms. In addition, it retains 97.2% of the initial capacitance after 10000 charge/discharge cycles. These outstanding performance characteristics of our device demonstrate its promising to replace the conventional AECs for ac line filtering. PMID:26084051

  17. Alternating current line-filter based on electrochemical capacitor utilizing template-patterned graphene

    PubMed Central

    Wu, Zhenkun; Li, Liyi; Lin, Ziyin; Song, Bo; Li, Zhuo; Moon, Kyoung-Sik; Wong, Ching-Ping; Bai, Shu-Lin

    2015-01-01

    Aluminum electrolytic capacitors (AECs) are widely used for alternating current (ac) line-filtering. However, their bulky size is becoming more and more incompatible with the rapid development of portable electronics. Here we report a scalable process to fabricate miniaturized graphene-based ac line-filters on flexible substrates at room temperature. In this work, graphene oxide (GO) is reduced by patterned metal interdigits at room temperature and used directly as the electrode material. The as-fabricated device shows a phase angle of −75.4° at 120 Hz with a specific capacitance of 316 µF/cm2 and a RC time constant of 0.35 ms. In addition, it retains 97.2% of the initial capacitance after 10000 charge/discharge cycles. These outstanding performance characteristics of our device demonstrate its promising to replace the conventional AECs for ac line filtering. PMID:26084051

  18. Measurements of the Downward Longwave Radiation Spectrum over the Antarctic Plateau and Comparisons with a Line-by-Line Radiative Transfer Model for Clear Skies

    NASA Technical Reports Server (NTRS)

    Walden, Von P.; Warren, Stephen G.; Murcray, Frank J.

    1998-01-01

    A 1-year field program was conducted at South Pole Station in 1992 to measure the downward infrared radiance spectrum at a resolution of 1/ cm over the spectral range 550-1667 cm-'. The atmosphere over the Antarctic Plateau is the coldest and driest on Earth, where in winter, surface temperatures average about -60 C, the total column water vapor is as low as 300 pm of precipitable water, and the clear-sky downward longwave flux is usually less than 80 W/sq m. Three clear-sky test cases are selected, one each for summer, winter, and spring, for which high- quality radiance data are available.as well as ancillary data to construct model atmospheres from radiosondes, ozonesondes, and other measurements. The model atmospheres are used in conjunction with the line-by-line radiative transfer model (LBLRTM) to compare model calculations with the spectral radiance measurements. The high-resolution calculations of LBLRTM (approx. = 0.001/ cm) are matched to the lower-resolution measurements (1/ cm) by adjusting their spectral resolution and by applying a correction for the finite field of view of the interferometer. In summer the uncertainties in temperature and water vapor profiles dominate the radiance error in the LBLRTM calculations. In winter the uncertainty in viewing zenith angle becomes important as well as the choice of atmospheric levels in the strong near-surface temperature inversion. The spectral radiance calculated for each of the three test cases generally agrees with that measured, to within twice the total estimated radiance error, thus validating LBLRTM to this level of accuracy for Antarctic conditions. However, the discrepancy exceeds twice the estimated error in the gaps between spectral lines in the region 1250-1500/ cm, where emission is dominated by the foreign-broadened water vapor continuum.

  19. Determination of High-Frequency Current Distribution Using EMTP-Based Transmission Line Models with Resulting Radiated Electromagnetic Fields

    SciTech Connect

    Mork, B; Nelson, R; Kirkendall, B; Stenvig, N

    2009-11-30

    Application of BPL technologies to existing overhead high-voltage power lines would benefit greatly from improved simulation tools capable of predicting performance - such as the electromagnetic fields radiated from such lines. Existing EMTP-based frequency-dependent line models are attractive since their parameters are derived from physical design dimensions which are easily obtained. However, to calculate the radiated electromagnetic fields, detailed current distributions need to be determined. This paper presents a method of using EMTP line models to determine the current distribution on the lines, as well as a technique for using these current distributions to determine the radiated electromagnetic fields.

  20. Shearless bifurcation on symplectic maps of magnetic field lines in tokamaks with reversed current

    NASA Astrophysics Data System (ADS)

    Bartoloni, B.; Schelin, A. B.; Caldas, I. L.

    2016-07-01

    We introduce two-dimensional symplectic maps to describe the Poincaré maps of magnetic field lines in large aspect ratio tokamak equilibria with reversed non-monotonic plasma current density profiles. For these maps, we investigate the effect of the symmetry breaking due to the toroidal correction with a peculiar invariant, namely, a magnetic surface with a null rotation number, enclosing a vanishing current. We find that this rotationless invariant surface is surrounded by many small island chains. Furthermore, near such invariant, the symmetry breaking gives rise to two magnetic shearless invariants surrounded by twin island chains. We also find chaotic lines adjacent to all the observed islands created by the considered structurally unstable equilibria.

  1. Particle Dynamics Discrimination Between Current Sheet Magnetic Field Reversal and Magnetic Neutral Line Fields

    NASA Astrophysics Data System (ADS)

    Martin, R. F., Jr.; Holland, D. L.; Svetich, J.

    2014-12-01

    We consider dynamical signatures of ion motion that discriminate between a current sheet magnetic field reversal and a magnetic neutral line field. These two related dynamical systems have been studied previously as chaotic scattering systems with application to the Earth's magnetotail. Both systems exhibit chaotic scattering over a wide range of parameter values. The structure and properties of their respective phase spaces have been used to elucidate potential dynamical signatures that affect spacecraft measured ion distributions. In this work we consider the problem of discrimination between these two magnetic structures using charged particle dynamics. For example we show that signatures based on the well known energy resonance in the current sheet field provide good discrimination since the resonance is not present in the neutral line case. While both fields can lead to fractal exit region structuring, their characteristics are different and also may provide some field discrimination. Application to magnetotail field and particle parameters will be presented

  2. Flux line non-equilibrium relaxation kinetics following current quenches in disordered type-II superconductors

    NASA Astrophysics Data System (ADS)

    Chaturvedi, Harshwardhan; Assi, Hiba; Dobramysl, Ulrich; Pleimling, Michel; Täuber, Uwe

    We investigate the relaxation dynamics of magnetic vortex lines in disordered type-II superconductors following rapid changes in the external driving current by means of Langevin molecular dynamics simulations for an elastic line model. A system of driven interacting flux lines in a sample with randomly distributed point pinning centers is initially relaxed to a moving non-equilibrium steady state. The current is then instantaneously decreased, such that the final stationary state resides either still in the moving regime, or in the pinned Bragg glass phase. The ensuing non-equilibrium relaxation kinetics of the vortices is studied in detail by measuring the mean flux line gyration radius and the two-time transverse height autocorrelation function. The latter allows us to investigate the physical aging properties for quenches from the moving into the glassy phase, and to compare with non-equilibrium relaxation features obtained with different initial configurations. Research supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Award DE-FG02-09ER46613.

  3. T(sub lambda) Depression by a Heat Current Along the lambda-Line

    NASA Technical Reports Server (NTRS)

    Liu, Yuanming; Larson, Melora; Iraelsson, Ulf E.

    1999-01-01

    We report measurements of the depression of the superfluid transition temperature by a heat current (1 less than or = Q less than or = 100 microW/sq cm) along the lambda-line (SVP less than or = P less than or = 21.6 bar). At P = 21.6 bar, measurements were also performed in a reduced gravity (0.2g). Experimental results show that the pressure dependence of the depression and the gravity effect on the measurements are small, in qualitative agreement with theoretical predictions. Keywords: superfluid helium; Lambda transition; heat current

  4. Magnetohydrodynamic Simulations of Current-Sheet Formation and Reconnection at a Magnetic X Line

    NASA Astrophysics Data System (ADS)

    DeVore, C. R.; Antiochos, S. K.; Karpen, J. T.; Black, C.

    2011-12-01

    Phenomena ranging from the quiescent heating of the ambient plasma to the highly explosive release of energy and acceleration of particles in flares are conjectured to result from magnetic reconnection at electric current sheets in the Sun's corona. We are investigating numerically, using a macroscopic magnetohydrodynamic (MHD) model with adaptive mesh refinement, the formation and reconnection of a current sheet in an initially potential 2D magnetic field containing a null. Subjecting this simple configuration to unequal stresses in the four quadrants bounded by the X-line separatrix distorts the potential null into a double-Y-line current sheet. We find that even small distortions of the magnetic field induce the formation of a tangential discontinuity in the high-beta region around the null. A continuously applied stress eventually leads to the onset of fast magnetic reconnection across the sheet, with copious production, merging, and ejection of magnetic islands. We compare the current-sheet development and evolution for three cases: quasi-ideal MHD with numerical resistivity only; uniformly resistive MHD; and MHD with an embedded kinetic reconnection model. Analogous kinetic simulations using particle-in-cell (PIC) methods to investigate the small-scale dynamics of the system also are being pursued (C. Black et al., this meeting). Our progress toward understanding this simple system will be reported, as will the implications of our results for the dynamic activity associated with coronal current sheets and for general multiscale modeling of magnetized plasmas in the Heliosphere. Our research was supported by NASA.

  5. High beam current shut-off systems in the APS linac and low energy transfer line

    SciTech Connect

    Wang, X.; Knott, M.; Lumpkin, A.

    1994-11-01

    Two independent high beam current shut-off current monitoring systems (BESOCM) have been installed in the APS linac and the low energy transport line to provide personnel safety protection in the event of acceleration of excessive beam currents. Beam current is monitored by a fast current transformer (FCT) and fully redundant supervisory circuits connected to the Access Control Interlock System (ACIS) for beam intensity related shutdowns of the linac. One FCT is located at the end of the positron linac and the other in the low energy transport line, which directs beam to the positron accumulator ring (PAR). To ensure a high degree of reliability, both systems employ a continuous self-checking function, which injects a test pulse to a single-turn test winding after each ``real`` beam pulse to verify that the system is fully functional. The system is designed to be fail-safe for all possible system faults, such as loss of power, open or shorted signal or test cables, loss of external trigger, malfunction of gated integrator, etc. The system has been successfully commissioned and is now a reliable part of the total ACIS.

  6. Practical hybrid fiber optic current sensor on a high-voltage power line

    NASA Astrophysics Data System (ADS)

    Zheng, Zhe; Chen, Zhan; Liu, Feng; Lu, Xin; Guo, Yanhui; Zheng, Shengxuan

    2000-10-01

    In this paper, the disadvantages of the traditional Current Transformer (CT) on high voltage power line are described. A new method to measure the high-voltage current is studied. A Practical Hybrid Fiber Optic Sensor for High-Voltage Current is developed and the result of the experiment and the errors are analyzed. This design consists of two parts. One is in the air attached with the high voltage power line and the other one is on the ground. In the upper part, a Rogowaski Loop is used to transform the current signal into voltage one, then a V/F converter is applied to change this voltage signal into frequency. After processed, the resulted frequency signal is fed to the LED, which turns the electrical signal into light one. Then, the light signal is lead along the optic fiber down to the ground. Here, the optic fiber is used for insulation purpose. On the ground the light signal is converted back into electrical signal with a photoelectric cell. After amplified and regulated, the electrical signal is fed to a F/V converter, which changes the frequency signal back into the original current signal.

  7. High-Resolution Chromosome Ideogram Representation of Currently Recognized Genes for Autism Spectrum Disorders

    PubMed Central

    Butler, Merlin G.; Rafi, Syed K.; Manzardo, Ann M.

    2015-01-01

    Recently, autism-related research has focused on the identification of various genes and disturbed pathways causing the genetically heterogeneous group of autism spectrum disorders (ASD). The list of autism-related genes has significantly increased due to better awareness with advances in genetic technology and expanding searchable genomic databases. We compiled a master list of known and clinically relevant autism spectrum disorder genes identified with supporting evidence from peer-reviewed medical literature sources by searching key words related to autism and genetics and from authoritative autism-related public access websites, such as the Simons Foundation Autism Research Institute autism genomic database dedicated to gene discovery and characterization. Our list consists of 792 genes arranged in alphabetical order in tabular form with gene symbols placed on high-resolution human chromosome ideograms, thereby enabling clinical and laboratory geneticists and genetic counsellors to access convenient visual images of the location and distribution of ASD genes. Meaningful correlations of the observed phenotype in patients with suspected/confirmed ASD gene(s) at the chromosome region or breakpoint band site can be made to inform diagnosis and gene-based personalized care and provide genetic counselling for families. PMID:25803107

  8. Excessive magnetic field flux density distribution from overhead isolated powerline conductors due to neutral line current.

    PubMed

    Netzer, Moshe

    2013-06-01

    Overhead isolated powerline conductors (hereinafter: "OIPLC") are the most compact form for distributing low voltage currents. From the known physics of magnetic field emission from 3-phase power lines, it is expected that excellent symmetry of the 120° shifted phase currents and where compact configuration of the 3-phase+neutral line exist, the phase current vectorial summation of the magnetic field flux density (MFFD) is expected to be extremely low. However, despite this estimation, an unexpectedly very high MFFD was found in at least three towns in Israel. This paper explains the reasons leading to high MFFD emissions from compact OIPLC and the proper technique to fix it. Analysis and measurement results had led to the failure hypothsis of neutral line poor connection design and poor grounding design of the HV-LV utility transformers. The paper elaborates on the low MFFD exposure level setup by the Israeli Environmental Protection Office which adopted a rather conservative precaution principal exposure level (2 mG averaged over 24 h). PMID:23675630

  9. Interstellar absorption lines in the spectrum of sigma Sco using Copernicus observations

    NASA Technical Reports Server (NTRS)

    Allen, M. M.; Snow, T. P.

    1986-01-01

    Since the launch of Copernicus in 1972, studies have been made of the depletion of gas-phase elements onto dust grains. A few stars have been studied in detail, resulting in a standard depletion pattern which has since been used for comparison. Recent developments, however, have suggested that this standard pattern may need to be re-examined. Some weak, semi-forbidden lines were detected recently which may be able to resolve some of the ambiguities. Studies of single elements have shown that depletion of carbon and oxgyen are much smaller than previously determined. The high resolution ultraviolet spectral scans of sigma Sco were originally made in 1973, but have only recently been analyzed. All these stars are bright and moderately reddened. All four stars will be analyzed in detail, but sigma Sco is the first one completed. The data has broad coverage of ions, making these stars excellent candidates for determination of accurate depletions. A profile-fitting analysis was used rather than curves-of-growth in order to determine separate abundances and depletions in components separated by several km/sec.

  10. Line-of-sight magnetic flux imbalances caused by electric currents

    NASA Technical Reports Server (NTRS)

    Gary, G. Allen; Rabin, Douglas

    1995-01-01

    Several physical and observational effects contribute to the significant imbalances of magnetic flux that are often observed in active regions. We consider an effect not previously treated: the influence of electric currents in the photosphere. Electric currents can cause a line-of-sight flux imbalance because of the directionality of the magnetic field they produce. Currents associated with magnetic flux tubes produce larger imbalances than do smoothly-varying distributions of flux and current. We estimate the magnitude of this effect for current densities, total currents, and magnetic geometry consistent with observations. The expected imbalances lie approximately in the range 0-15%, depending on the character of the current-carying fields and the angle from which they are viewed. Observationally, current-induced flux imbalances could be indicated by a statistical dependence of the imbalance on angular distance from disk center. A general study of magnetic flux balance in active regions is needed to determine the relative importance of other- probably larger- effects such as dilute flux (too weak to measure or rendered invisible by radiative transfer effects), merging with weak background fields, and long-range connections between active regions.

  11. The Power Spectrum of Ionic Nanopore Currents: The Role of Ion Correlations.

    PubMed

    Zorkot, Mira; Golestanian, Ramin; Bonthuis, Douwe Jan

    2016-04-13

    We calculate the power spectrum of electric-field-driven ion transport through nanometer-scale membrane pores using both linearized mean-field theory and Langevin dynamics simulations. Remarkably, the linearized mean-field theory predicts a plateau in the power spectral density at low frequency ω, which is confirmed by the simulations at low ion concentration. At high ion concentration, however, the power spectral density follows a power law that is reminiscent of the 1/ω(α) dependence found experimentally at low frequency. On the basis of simulations with and without ion-ion interactions, we attribute the low-frequency power-law dependence to ion-ion correlations. We show that neither a static surface charge density, nor an increased pore length, nor an increased ion valency have a significant effect on the shape of the power spectral density at low frequency. PMID:26977905

  12. World line dependence of current sheet normals inferred by minimum variance techniques

    NASA Astrophysics Data System (ADS)

    Scudder, J. D.; Ma, Z.-W.; Omidi, N.; Puhl-Quinn, P.

    2005-08-01

    The reconstruction of current sheet geometry is investigated as a function of paths through an oblique two-dimensional (2-D) hybrid supercritical shock and two fluid simulations of the magnetopause with no, small, and large guide fields, respectively. For world lines near the separator or 2-D structures in shocks, systematic errors swamp statistical ones tenfold. The systematic angular errors of the magnetopause surface normal determined by minimum variance analysis (MVA) using >100,000 world lines are contrasted with recommended statistical error cones. The systematic errors range as high as 90° but typically more than 20°. Errors do not have a most probable value at the magnetopause when using MVA on the magnetic data, MnVA(B), and remain substantial when the Faraday residue, MnVA(FR), is minimized. The 68% confidence error on MnVA(FR) normals is 0-15°. "Skimming" world lines oblique to the current sheet normal are the most susceptible to the MnVA(B) and MnVA(FR) systematic errors discussed here, whether or not the world line pierces the separator. MnVA(B) almost always erroneously insists that a guide field is present when none is present in the simulation. MnVA(FR) does a better job at guide field recovery, although it too can be error prone. Similar issues are demonstrated for oblique world lines through a 2-D hybrid simulation of an oblique supercritical shock. Shock normal systematic errors are 35° and 20° at the 68% confidence for MnVA(B) and MnVA(FR), respectively. The eigenvalue ratios that accompany the least error prone MnVA(FR) reconstructions usually satisfy λ2/λ1 > 10. Eigenvalue ratios for MVA(B) are rarely this large, and the errors reported here reflect this circumstance.

  13. Designing spectrum-splitting dichroic filters to optimize current-matched photovoltaics.

    PubMed

    Miles, Alexander; Cocilovo, Byron; Wheelwright, Brian; Pan, Wei; Tweet, Doug; Norwood, Robert A

    2016-03-10

    We have developed an approach for designing a dichroic coating to optimize performance of current-matched multijunction photovoltaic cells while diverting unused light. By matching the spectral responses of the photovoltaic cells and current matching them, substantial improvement to system efficiencies is shown to be possible. A design for use in a concentrating hybrid solar collector was produced by this approach, and is presented. Materials selection, design methodology, and tilt behavior on a curved substrate are discussed. PMID:26974772

  14. Nonuniformity in amorphous ribbon delay lines after stress and current annealing

    NASA Astrophysics Data System (ADS)

    Hristoforou, E.; Reilly, R. E.

    1991-04-01

    Experimental results concerning the reduction of the amplitude nonuniformity of a Metglas 2605SC magnetostrictive delay line (MDL) after stress relief and current annealing under stress are reported. Nonuniformity is defined here as the fluctuation of the peak voltage V0 received by a coil around the MDL at a fixed position versus the distance between the coil and the point of excitation by a pulsed magnetic field, under uniform conditions of bias field and geometry along the length of the MDL. Stress-relieved delay lines were subjected to stress and current annealing. The results show that the fluctuation function was improved for a stress-relieved MDL, subjected to 200 N/mm2 stress and 300 m amps dc longitudinal annealing current. It was also observed that the normalized relationship for V0 versus the exciting pulsed current is the same for any point of excitation under uniform conditions of dc bias field. This could be used to simplify a computational correction of the nonuniformity function.

  15. Effects of energy distribution of interface traps on recombination dc current-voltage line shape

    NASA Astrophysics Data System (ADS)

    Chen, Zuhui; Jie, Bin B.; Sah, Chih-Tang

    2006-12-01

    The effects of energy distributions of Si /SiO2 interface traps in the energy gap of oxidized silicon on the current versus voltage line shape of the electron-hole recombination current are analyzed using the steady-state Shockley-Read-Hall kinetics. Slater's [Insulators, Semiconductors and Metals; Quantum Theory of Molecules and Solids (McGraw-Hill, New York, 1967)] localized bulk perturbation theory applied by us to the interface anticipates U-shaped energy distributions of the density of neutral electron and hole interface traps from random variations of the Si:Si and Si:O bond angles and lengths. Conservation in dissipative transition energy anticipates the rate of electron capture into neutral electron trap to be faster for electron trap energy levels nearer the conduction band edge, and similarly, the rate of hole capture into neutral hole trap to be faster for hole trap energy levels nearer the valence band edge. Line shape broadening is analyzed for discrete and U-shaped energy distributions of interface trap energy levels. The broadened line shapes observed in past experiments, previously attributed to spatial variations of surface dopant impurity concentrations, could also arise from energy distributions of interface trap energy levels.

  16. Numerical Calculation of the Spectrum of the Severe (1%) Lighting Current and Its First Derivative

    SciTech Connect

    Brown, C G; Ong, M M; Perkins, M P; Speer, R D

    2010-02-12

    Recently, the direct-strike lighting environment for the stockpile-to-target sequence was updated [1]. In [1], the severe (1%) lightning current waveforms for first and subsequent return strokes are defined based on Heidler's waveform. This report presents numerical calculations of the spectra of those 1% lightning current waveforms and their first derivatives. First, the 1% lightning current models are repeated here for convenience. Then, the numerical method for calculating the spectra is presented and tested. The test uses a double-exponential waveform and its first derivative, which we fit to the previous 1% direct-strike lighting environment from [2]. Finally, the resulting spectra are given and are compared with those of the double-exponential waveform and its first derivative.

  17. Clinical and Neurobiological Relevance of Current Animal Models of Autism Spectrum Disorders.

    PubMed

    Kim, Ki Chan; Gonzales, Edson Luck; Lázaro, María T; Choi, Chang Soon; Bahn, Geon Ho; Yoo, Hee Jeong; Shin, Chan Young

    2016-05-01

    Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social and communication impairments, as well as repetitive and restrictive behaviors. The phenotypic heterogeneity of ASD has made it overwhelmingly difficult to determine the exact etiology and pathophysiology underlying the core symptoms, which are often accompanied by comorbidities such as hyperactivity, seizures, and sensorimotor abnormalities. To our benefit, the advent of animal models has allowed us to assess and test diverse risk factors of ASD, both genetic and environmental, and measure their contribution to the manifestation of autistic symptoms. At a broader scale, rodent models have helped consolidate molecular pathways and unify the neurophysiological mechanisms underlying each one of the various etiologies. This approach will potentially enable the stratification of ASD into clinical, molecular, and neurophenotypic subgroups, further proving their translational utility. It is henceforth paramount to establish a common ground of mechanistic theories from complementing results in preclinical research. In this review, we cluster the ASD animal models into lesion and genetic models and further classify them based on the corresponding environmental, epigenetic and genetic factors. Finally, we summarize the symptoms and neuropathological highlights for each model and make critical comparisons that elucidate their clinical and neurobiological relevance. PMID:27133257

  18. Clinical and Neurobiological Relevance of Current Animal Models of Autism Spectrum Disorders

    PubMed Central

    Kim, Ki Chan; Gonzales, Edson Luck; Lázaro, María T.; Choi, Chang Soon; Bahn, Geon Ho; Yoo, Hee Jeong; Shin, Chan Young

    2016-01-01

    Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social and communication impairments, as well as repetitive and restrictive behaviors. The phenotypic heterogeneity of ASD has made it overwhelmingly difficult to determine the exact etiology and pathophysiology underlying the core symptoms, which are often accompanied by comorbidities such as hyperactivity, seizures, and sensorimotor abnormalities. To our benefit, the advent of animal models has allowed us to assess and test diverse risk factors of ASD, both genetic and environmental, and measure their contribution to the manifestation of autistic symptoms. At a broader scale, rodent models have helped consolidate molecular pathways and unify the neurophysiological mechanisms underlying each one of the various etiologies. This approach will potentially enable the stratification of ASD into clinical, molecular, and neurophenotypic subgroups, further proving their translational utility. It is henceforth paramount to establish a common ground of mechanistic theories from complementing results in preclinical research. In this review, we cluster the ASD animal models into lesion and genetic models and further classify them based on the corresponding environmental, epigenetic and genetic factors. Finally, we summarize the symptoms and neuropathological highlights for each model and make critical comparisons that elucidate their clinical and neurobiological relevance. PMID:27133257

  19. Measurement of Bacterial Bioluminescence Intensity and Spectrum: Current Physical Techniques and Principles.

    PubMed

    Jia, Kun; Ionescu, Rodica Elena

    2016-01-01

    : Bioluminescence is light production by living organisms, which can be observed in numerous marine creatures and some terrestrial invertebrates. More specifically, bacterial bioluminescence is the "cold light" produced and emitted by bacterial cells, including both wild-type luminescent and genetically engineered bacteria. Because of the lively interplay of synthetic biology, microbiology, toxicology, and biophysics, different configurations of whole-cell biosensors based on bacterial bioluminescence have been designed and are widely used in different fields, such as ecotoxicology, food toxicity, and environmental pollution. This chapter first discusses the background of the bioluminescence phenomenon in terms of optical spectrum. Platforms for bacterial bioluminescence detection using various techniques are then introduced, such as a photomultiplier tube, charge-coupled device (CCD) camera, micro-electro-mechanical systems (MEMS), and complementary metal-oxide-semiconductor (CMOS) based integrated circuit. Furthermore, some typical biochemical methods to optimize the analytical performances of bacterial bioluminescent biosensors/assays are reviewed, followed by a presentation of author's recent work concerning the improved sensitivity of a bioluminescent assay for pesticides. Finally, bacterial bioluminescence as implemented in eukaryotic cells, bioluminescent imaging, and cancer cell therapies is discussed. PMID:25981856

  20. Development of an electrical current sensor prototype for applications in high-power lines

    NASA Astrophysics Data System (ADS)

    Nascimento, I. M.; Brígida, A. C. S.; Baptista, J. M.; Costa, J. C. W. A.; Martinez, M. A. G.; Jorge, P. A. S.

    2013-11-01

    A magneto-optical current sensor, based on a low birefringence SF57 glass prism, using a dual quadrature polarimetric configuration was implemented and tested aiming its application in high voltage power lines. Sensor operation is characterized and compared using distinct Super Luminescent Diodes as optical sources, with emission at 650 nm, 830 nm and 1550 nm. Calibration and resolution are obtained in the different operating conditions using a DAQ board and full digital control for signal acquisition and processing. In particular, the sensor was tested in the range from 0 to 1 kA at 50 Hz. Also, operation at different frequencies from 50 Hz to 400 Hz was compared. A robust casing was fabricated in Nylon material enabling the portability of the sensor and its application in different types of conductors. Preliminary results indicate the feasibility of using the sensor both for metering and protection applications in high-power lines with interrogation via the OPGW cable.

  1. Sharp edges in solar microwave spectra - Neutral current sheets or cyclotron lines?

    NASA Technical Reports Server (NTRS)

    Schmahl, E. J.; Kundu, M. R.; Shevgaonkar, R. K.; Mcconnell, D.

    1984-01-01

    Two solar active regions have been mapped using the VLA at three closely spaced frequencies (4496, 4716, and 4996 MHz) in an attempt to determine the origin of the steep spectra (index gamma equal to about -5 to -8) sometimes observed with large single telescopes. One of the regions observed indeed shows an anomalously large slope (gamma equal to about -6) compared to the usual (gamma equal to about -2 to -2.5). The other region shows a similar slope (gamma equal to about -5) but with a larger range of statistical error. Two possible explanations for such steep edges in solar spectra are (1) transmission effects of neutral current sheets, and (2) the appearance of cyclotron lines. The internal evidence of the microwave maps and simultaneous optical observations favor an explanation in terms of cyclotron lines.

  2. Modelling the VUV emission spectrum of N2: preliminary results on the effects of rotational interactions on line intensities.

    PubMed

    Edwards, S A; Tchang-Brillet, W U; Roncin, J Y; Launay, F; Rostas, F

    1995-01-01

    A theoretical model of the excited singlet ungerade electronic states of the nitrogen molecule is presented. This work is an extension of a previous study (D. Stahel, M. Leoni and K. Dressler, J. Chem. Phys. 79, 2541-2558, 1983) with the addition of rotational interactions between states of different symmetry. These rotational interactions together with the homogeneous couplings frequently lead to extreme mixing of the states. This model is being used to analyse the high resolution vacuum ultraviolet emission spectrum which is currently being recorded photoelectrically. The ultimate goal of this work is the reliable interpretation of the low resolution emission spectra observed from planetary atmospheres, notably that of Titan, and the transitions assigned as being important in the Voyager 1 spectra of Titan are discussed in detail. PMID:11538439

  3. A Short Review on the Current Understanding of Autism Spectrum Disorders.

    PubMed

    Park, Hye Ran; Lee, Jae Meen; Moon, Hyo Eun; Lee, Dong Soo; Kim, Bung-Nyun; Kim, Jinhyun; Kim, Dong Gyu; Paek, Sun Ha

    2016-02-01

    Autism spectrum disorder (ASD) is a set of neurodevelopmental disorders characterized by a deficit in social behaviors and nonverbal interactions such as reduced eye contact, facial expression, and body gestures in the first 3 years of life. It is not a single disorder, and it is broadly considered to be a multi-factorial disorder resulting from genetic and non-genetic risk factors and their interaction. Genetic studies of ASD have identified mutations that interfere with typical neurodevelopment in utero through childhood. These complexes of genes have been involved in synaptogenesis and axon motility. Recent developments in neuroimaging studies have provided many important insights into the pathological changes that occur in the brain of patients with ASD in vivo. Especially, the role of amygdala, a major component of the limbic system and the affective loop of the cortico-striatothalamo-cortical circuit, in cognition and ASD has been proved in numerous neuropathological and neuroimaging studies. Besides the amygdala, the nucleus accumbens is also considered as the key structure which is related with the social reward response in ASD. Although educational and behavioral treatments have been the mainstay of the management of ASD, pharmacological and interventional treatments have also shown some benefit in subjects with ASD. Also, there have been reports about few patients who experienced improvement after deep brain stimulation, one of the interventional treatments. The key architecture of ASD development which could be a target for treatment is still an uncharted territory. Further work is needed to broaden the horizons on the understanding of ASD. PMID:26924928

  4. A Short Review on the Current Understanding of Autism Spectrum Disorders

    PubMed Central

    Park, Hye Ran; Lee, Jae Meen; Moon, Hyo Eun; Lee, Dong Soo; Kim, Bung-Nyun; Kim, Jinhyun; Kim, Dong Gyu

    2016-01-01

    Autism spectrum disorder (ASD) is a set of neurodevelopmental disorders characterized by a deficit in social behaviors and nonverbal interactions such as reduced eye contact, facial expression, and body gestures in the first 3 years of life. It is not a single disorder, and it is broadly considered to be a multi-factorial disorder resulting from genetic and non-genetic risk factors and their interaction. Genetic studies of ASD have identified mutations that interfere with typical neurodevelopment in utero through childhood. These complexes of genes have been involved in synaptogenesis and axon motility. Recent developments in neuroimaging studies have provided many important insights into the pathological changes that occur in the brain of patients with ASD in vivo. Especially, the role of amygdala, a major component of the limbic system and the affective loop of the cortico-striatothalamo-cortical circuit, in cognition and ASD has been proved in numerous neuropathological and neuroimaging studies. Besides the amygdala, the nucleus accumbens is also considered as the key structure which is related with the social reward response in ASD. Although educational and behavioral treatments have been the mainstay of the management of ASD, pharmacological and interventional treatments have also shown some benefit in subjects with ASD. Also, there have been reports about few patients who experienced improvement after deep brain stimulation, one of the interventional treatments. The key architecture of ASD development which could be a target for treatment is still an uncharted territory. Further work is needed to broaden the horizons on the understanding of ASD. PMID:26924928

  5. Analytic Aharonov-Bohm rings — Currents readout from Zeeman spectrum

    NASA Astrophysics Data System (ADS)

    Xiao, Mufei; Reyes-Serrato, Armando

    2016-06-01

    This paper reports the work on the development and analysis of a model for quantum rings in which persistent currents are induced by Aharonov-Bohm (AB) or other similar effects. The model is based on a centric and annual potential profile. The time-independent Schrödinger equation including an external magnetic field and an AB flux is analytically solved. The outputs, namely energy dispersion and wavefunctions, are analyzed in detail. It is shown that the rotation quantum number m is limited to small numbers, especially in weak confinement, and a conceptual proposal is put forward for acquiring the flux and eventually estimating the persistent currents in a Zeeman spectroscopy. The wavefunctions and electron distributions are numerically studied and compared to one-dimensional (1D) quantum well. It is predicated that the model and its solutions, eigen energy structure and analytic wavefunctions, would be a powerful tool for studying various electric and optical properties of quantum rings.

  6. Current noise spectrum and capacitance due to the membrane motor of the outer hair cell: theory.

    PubMed Central

    Iwasa, K H

    1997-01-01

    The voltage-dependent motility of the outer hair cell is based on a membrane motor densely distributed in the lateral membrane. The gating charge of the membrane motor is manifested as a bell-shaped membrane potential dependence of the membrane capacitance. In this paper it is shown that movements of the gating charge should produce a high-pass current noise described by an inverse Lorentzian similar to the one shown by Kolb and Läuger for ion carriers. The frequency dependence of the voltage-dependent capacitance is also derived. These derivations are based on membrane motor models with two or three states. These two models lead to similar predictions on the capacitance and current noise. It is expected that the examination of the spectral properties of these quantities would be a useful means of determining the relaxation time for conformational transitions of the membrane motor. PMID:9414211

  7. Biased impurity tunneling current emission spectrum in the presence of quasi-particle interaction

    NASA Astrophysics Data System (ADS)

    Maslova, N. S.; Arseyev, P. I.; Mantsevich, V. N.

    2016-09-01

    We performed theoretical investigations of the tunneling current noise spectra through single-level impurity in the presence of quasi-particle (electron-phonon) interaction by means of the non-equilibrium Green function formalism. We demonstrated a fundamental link between quantum noise in tunneling contact and light emission processes. We calculated tunneling current noise spectra through a single level impurity atom both in the presence and in the absence of quasi-particle interaction for a finite bias voltage and identified it as a source of experimentally observed light emission from bias STM contacts. The results turn out to be sensitive to the tunneling contact parameters. Our findings provide important insight into the nature of non-equilibrium electronic transport in tunneling junctions with quasi-particle interaction.

  8. Remarks on the discrete Alfvén wave spectrum induced by the Hall current

    NASA Astrophysics Data System (ADS)

    Ito, Atsushi; Hirose, Akira; Mahajan, Swadesh M.; Ohsaki, Shuichi

    2004-12-01

    It is shown that the discrete Alfvén wave induced by the Hall current [S. Ohsaki and S. M. Mahajan, Phys. Plasmas 11, 898 (2004)] is equivalent to the kinetic Alfvén wave (KAW). The KAW is, thus, accessible in a fluid description. It is further shown that the dispersion relation for the Hall magnetohydrodynamic waves can be reproduced from kinetic theory only if the ion temperature is negligible compared with the electron temperature.

  9. Temperature-dependence of Threshold Current Density-Length Product in Metallization Lines: A Revisit

    NASA Astrophysics Data System (ADS)

    Saptono Duryat, Rahmat; Kim, Choong-Un

    2016-04-01

    One of the important phenomena in Electromigration (EM) is Blech Effect. The existence of Threshold Current Density-Length Product or EM Threshold has such fundamental and technological consequences in the design, manufacture, and testing of electronics. Temperature-dependence of Blech Product had been thermodynamically established and the real behavior of such interconnect materials have been extensively studied. The present paper reviewed the temperature-dependence of EM threshold in metallization lines of different materials and structure as found in relevant published articles. It is expected that the reader can see a big picture from the compiled data, which might be overlooked when it was examined in pieces.

  10. Peroxisome biogenesis disorders in the Zellweger spectrum: An overview of current diagnosis, clinical manifestations, and treatment guidelines.

    PubMed

    Braverman, Nancy E; Raymond, Gerald V; Rizzo, William B; Moser, Ann B; Wilkinson, Mark E; Stone, Edwin M; Steinberg, Steven J; Wangler, Michael F; Rush, Eric T; Hacia, Joseph G; Bose, Mousumi

    2016-03-01

    Peroxisome biogenesis disorders in the Zellweger spectrum (PBD-ZSD) are a heterogeneous group of genetic disorders caused by mutations in PEX genes responsible for normal peroxisome assembly and functions. As a result of impaired peroxisomal activities, individuals with PBD-ZSD can manifest a complex spectrum of clinical phenotypes that typically result in shortened life spans. The extreme variability in disease manifestation ranging from onset of profound neurologic symptoms in newborns to progressive degenerative disease in adults presents practical challenges in disease diagnosis and medical management. Recent advances in biochemical methods for newborn screening and genetic testing have provided unprecedented opportunities for identifying patients at the earliest possible time and defining the molecular bases for their diseases. Here, we provide an overview of current clinical approaches for the diagnosis of PBD-ZSD and provide broad guidelines for the treatment of disease in its wide variety of forms. Although we anticipate future progress in the development of more effective targeted interventions, the current guidelines are meant to provide a starting point for the management of these complex conditions in the context of personalized health care. PMID:26750748

  11. Driving toroidally asymmetric current through the tokamak scrape-off layer, Part II: Magnetic field structure and spectrum

    SciTech Connect

    Joseph, I

    2009-04-08

    The structure of the magnetic field perturbations due to non-axisymmetric field-aligned currents in the tokamak scrape-off layer (SOL) are analytically calculated near the X-point. Part I [I. Joseph, et al., submitted to Phys. Plasmas (2008)] demonstrated that biasing divertor target plates in a toroidally asymmetric fashion can generate an appreciable toroidally asymmetric parallel current density in the SOL along the separatrix. Here, the magnetic field perturbation caused by a SOL current channel of finite width and step-wise constant amplitude at the target plate is derived. Flux expansion amplifies the magnetic perturbation near the X-point, while phase interference causes the SOL amplitude to be reduced at large toroidal mode number. Far enough from the current channel, the magnetic field can be approximated as arising from a surface current near the separatrix with differing amplitudes in the SOL and the divertor leg. The perturbation spectrum and resonant components of this field are computed analytically asymptotically close to the separatrix in magnetic flux coordinates. The size of the stochastic layer due to the applied perturbation that would result without self-consistent plasma shielding is also estimated. If enough resonant field is generated, control of the edge pressure gradient may allow stabilization of edge localized modes.

  12. Resting State Functional Connectivity MRI among Spectral MEG Current Sources in Children on the Autism Spectrum.

    PubMed

    Datko, Michael; Gougelet, Robert; Huang, Ming-Xiong; Pineda, Jaime A

    2016-01-01

    Social and communicative impairments are among the core symptoms of autism spectrum disorders (ASD), and a great deal of evidence supports the notion that these impairments are associated with aberrant functioning and connectivity of various cortical networks. The present study explored the links between sources of MEG amplitude in various frequency bands and functional connectivity MRI in the resting state. The goal of combining these modalities was to use sources of neural oscillatory activity, measured with MEG, as functionally relevant seed regions for a more traditional pairwise fMRI connectivity analysis. We performed a seed-based connectivity analysis on resting state fMRI data, using seed regions derived from frequency-specific amplitude sources in resting state MEG data in the same nine subjects with ASD (10-17 years of age). We then compared fMRI connectivity among these MEG-source-derived regions between participants with autism and typically developing, age-matched controls. We used a source modeling technique designed for MEG data to detect significant amplitude sources in six frequency bands: delta (2-4 Hz), theta (4-8 Hz), alpha (8-12 Hz), beta (12-30 Hz), low gamma (30-60 Hz), and high gamma (60-120 Hz). MEG-derived source maps for each participant were co-registered in standard MNI space, and group-level source maps were obtained for each frequency. For each frequency band, the 10 largest clusters resulting from these t-tests were used as regions of interest (ROIs) for the fMRI functional connectivity analysis. Pairwise BOLD signal correlations were obtained between each pair of these ROIs for each frequency band. Each pairwise correlation was compared between the ASD and TD groups using t-tests. We also constrained these pairwise correlations to known network structures, resulting in a follow-up set of correlation matrices specific to each network we considered. Frequency-specific MEG sources had distinct patterns of fMRI resting state functional

  13. Resting State Functional Connectivity MRI among Spectral MEG Current Sources in Children on the Autism Spectrum

    PubMed Central

    Datko, Michael; Gougelet, Robert; Huang, Ming-Xiong; Pineda, Jaime A.

    2016-01-01

    Social and communicative impairments are among the core symptoms of autism spectrum disorders (ASD), and a great deal of evidence supports the notion that these impairments are associated with aberrant functioning and connectivity of various cortical networks. The present study explored the links between sources of MEG amplitude in various frequency bands and functional connectivity MRI in the resting state. The goal of combining these modalities was to use sources of neural oscillatory activity, measured with MEG, as functionally relevant seed regions for a more traditional pairwise fMRI connectivity analysis. We performed a seed-based connectivity analysis on resting state fMRI data, using seed regions derived from frequency-specific amplitude sources in resting state MEG data in the same nine subjects with ASD (10–17 years of age). We then compared fMRI connectivity among these MEG-source-derived regions between participants with autism and typically developing, age-matched controls. We used a source modeling technique designed for MEG data to detect significant amplitude sources in six frequency bands: delta (2–4 Hz), theta (4–8 Hz), alpha (8–12 Hz), beta (12–30 Hz), low gamma (30–60 Hz), and high gamma (60–120 Hz). MEG-derived source maps for each participant were co-registered in standard MNI space, and group-level source maps were obtained for each frequency. For each frequency band, the 10 largest clusters resulting from these t-tests were used as regions of interest (ROIs) for the fMRI functional connectivity analysis. Pairwise BOLD signal correlations were obtained between each pair of these ROIs for each frequency band. Each pairwise correlation was compared between the ASD and TD groups using t-tests. We also constrained these pairwise correlations to known network structures, resulting in a follow-up set of correlation matrices specific to each network we considered. Frequency-specific MEG sources had distinct patterns of fMRI resting

  14. A current filamentation mechanism for breaking magnetic field lines during reconnection.

    PubMed

    Che, H; Drake, J F; Swisdak, M

    2011-06-01

    During magnetic reconnection, the field lines must break and reconnect to release the energy that drives solar and stellar flares and other explosive events in space and in the laboratory. Exactly how this happens has been unclear, because dissipation is needed to break magnetic field lines and classical collisions are typically weak. Ion-electron drag arising from turbulence, dubbed 'anomalous resistivity', and thermal momentum transport are two mechanisms that have been widely invoked. Measurements of enhanced turbulence near reconnection sites in space and in the laboratory support the anomalous resistivity idea but there has been no demonstration from measurements that this turbulence produces the necessary enhanced drag. Here we report computer simulations that show that neither of the two previously favoured mechanisms controls how magnetic field lines reconnect in the plasmas of greatest interest, those in which the magnetic field dominates the energy budget. Rather, we find that when the current layers that form during magnetic reconnection become too intense, they disintegrate and spread into a complex web of filaments that causes the rate of reconnection to increase abruptly. This filamentary web can be explored in the laboratory or in space with satellites that can measure the resulting electromagnetic turbulence. PMID:21633355

  15. Accurate modeling of fluorescence line narrowing difference spectra: Direct measurement of the single-site fluorescence spectrum

    NASA Astrophysics Data System (ADS)

    Reppert, Mike; Naibo, Virginia; Jankowiak, Ryszard

    2010-07-01

    Accurate lineshape functions for modeling fluorescence line narrowing (FLN) difference spectra (ΔFLN spectra) in the low-fluence limit are derived and examined in terms of the physical interpretation of various contributions, including photoproduct absorption and emission. While in agreement with the earlier results of Jaaniso [Proc. Est. Acad. Sci., Phys., Math. 34, 277 (1985)] and Fünfschilling et al. [J. Lumin. 36, 85 (1986)], the derived formulas differ substantially from functions used recently [e.g., M. Rätsep et al., Chem. Phys. Lett. 479, 140 (2009)] to model ΔFLN spectra. In contrast to traditional FLN spectra, it is demonstrated that for most physically reasonable parameters, the ΔFLN spectrum reduces simply to the single-site fluorescence lineshape function. These results imply that direct measurement of a bulk-averaged single-site fluorescence lineshape function can be accomplished with no complicated extraction process or knowledge of any additional parameters such as site distribution function shape and width. We argue that previous analysis of ΔFLN spectra obtained for many photosynthetic complexes led to strong artificial lowering of apparent electron-phonon coupling strength, especially on the high-energy side of the pigment site distribution function.

  16. A new approach to detect broken rotor bars in induction machines by current spectrum analysis

    NASA Astrophysics Data System (ADS)

    Didier, G.; Ternisien, E.; Caspary, O.; Razik, H.

    2007-02-01

    This paper deals with a new technique to detect broken rotor bars in polyphase induction machines. Like most techniques, we employ the Fourier Transform of the stator current to make detection. But where the other methods use the Fourier Transform modulus, this alternative approach proposes to analyse its phase. As shown by results, the Fourier Transform phase allows to detect one broken rotor bar when the motor operates under a low load but the method robustness decreases for a half-broken rotor bar. So, in order to improve the diagnosis and to permit the detection of incipient broken rotor bar, the analysis is completed with the Hilbert Transform. This transform provides good results and a partially broken rotor bar can be detected when the load torque is equal or greater than 25%. The main advantage of these methods is that the final decision on the rotor cage state is took without the healthy motor reference.

  17. The discrete Alfvén wave spectrum induced by the Hall current

    NASA Astrophysics Data System (ADS)

    Ito, Atsushi; Hirose, Akira; Mahajan, Swadesh; Ohsaki, Shuichi

    2004-11-01

    It is shown that the discrete Alfvén wave induced by the Hall current [S. Ohsaki and S. M. Mahajan, Phys. Plasmas 11, 898 (2004)] is equivalent to the kinetic Alfvén wave (KAW). The Hall magnetohydrodynamic (MHD) dispersion relation can be fully recovered from the electromagnetic kinetic dispersion relation provided the ion temperature is negligible and the magnetosonic perturbation is retained. Effects of a finite ion temperature on the Hall MHD have been identified in the first order of ion FLR parameter and β_i. As expected, the MHD mode equation becomes anisotropic because of the double adiabaticity in ion dynamics even when the ion temperature is isotropic.

  18. Identification of the Double Lines in the Photographic-Infrared Spectrum of the Mira-Type Carbon Star U Cygni near Maximum Light

    NASA Astrophysics Data System (ADS)

    Hirai, M.

    The author reports the results of further spectroscopic analysis of the double lines which were suggested by Hirai and Nagasawa (1980) in the photographic-infrared spectrum of U Cygni near maximum light. Each line has two components, and the excitation temperatures derived from the short- and long-wavelength components are about 3,000K and 2,520K, respectively. The turbulent velocity of the s-component is 1.26 times larger than of the 1-component. Other physical parameters related to the cool atmosphere are obtained using both the synthetic-spectrum and curve-of-growth methods. Possible models to explain the double-line phenomena in the Mira-type carbon star U Cygni are discussed.

  19. Multiple calcium currents in a thyroid C-cell line: biophysical properties and pharmacology.

    PubMed

    Biagi, B A; Enyeart, J J

    1991-06-01

    The whole cell version of the patch-clamp technique was used to characterize voltage-gated Ca2+ channels in the calcitonin-secreting rat thyroid C-cell line 6-23 (clone 6). Three types of Ca2+ channels could be distinguished based on differences in voltage dependence, kinetics, and pharmacological sensitivity. T-type current was half-maximal at -31 mV, showed steady-state voltage-dependent inactivation that was half-maximal at -57 mV, inactivated with a voltage-dependent time constant that reached a minimum of 20 ms at potentials positive to -20 mV, and deactivated with a single time constant of approximately 2 ms at -80 mV. Reactivation of inactivated channels occurred with a time constant of 1.26 s at -90 mV. T current was selectively blocked by Ni2+ at concentrations between 5 and 50 microM. La3+ and Y3+ blocked the T current at 10- to 20-fold lower concentrations. Dihydropyridine-sensitive L-type current was half-maximal at a test potential of -3 mV and was approximately doubled in size when Ba2+ replaced Ca2+ as the charge carrier. Unlike L-type Ca2+ current in many cells, this current in C-cells displayed little Ca(2+)-dependent inactivation. N-type current was composed of inactivating and sustained components that were inhibited by omega-conotoxin. The inactivating component was half-maximal at +9 mV and could be fitted by two exponentials with time constants of 22 and 142 ms. A slow inactivation of N current with a time constant of 24.9 s was observed upon switching the holding potential from -80 to -40 mV. These results demonstrate that, similar to other neural crest derived cells, thyroid C-cells express multiple Ca2+ channels, including one previously observed only in neurons. PMID:1647663

  20. Traditional and non-traditional treatments for autism spectrum disorder with seizures: an on-line survey

    PubMed Central

    2011-01-01

    Background Despite the high prevalence of seizure, epilepsy and abnormal electroencephalograms in individuals with autism spectrum disorder (ASD), there is little information regarding the relative effectiveness of treatments for seizures in the ASD population. In order to determine the effectiveness of traditional and non-traditional treatments for improving seizures and influencing other clinical factor relevant to ASD, we developed a comprehensive on-line seizure survey. Methods Announcements (by email and websites) by ASD support groups asked parents of children with ASD to complete the on-line surveys. Survey responders choose one of two surveys to complete: a survey about treatments for individuals with ASD and clinical or subclinical seizures or abnormal electroencephalograms, or a control survey for individuals with ASD without clinical or subclinical seizures or abnormal electroencephalograms. Survey responders rated the perceived effect of traditional antiepileptic drug (AED), non-AED seizure treatments and non-traditional ASD treatments on seizures and other clinical factors (sleep, communication, behavior, attention and mood), and listed up to three treatment side effects. Results Responses were obtained concerning 733 children with seizures and 290 controls. In general, AEDs were perceived to improve seizures but worsened other clinical factors for children with clinical seizure. Valproic acid, lamotrigine, levetiracetam and ethosuximide were perceived to improve seizures the most and worsen other clinical factors the least out of all AEDs in children with clinical seizures. Traditional non-AED seizure and non-traditional treatments, as a group, were perceived to improve other clinical factors and seizures but the perceived improvement in seizures was significantly less than that reported for AEDs. Certain traditional non-AED treatments, particularly the ketogenic diet, were perceived to improve both seizures and other clinical factors. For ASD

  1. Application of Caco-2 Cell Line in Herb-Drug Interaction Studies: Current Approaches and Challenges

    PubMed Central

    Awortwe, C.; Fasinu, P.S.; Rosenkranz, B.

    2015-01-01

    The Caco-2 model is employed in pre-clinical investigations to predict the likely gastrointestinal permeability of drugs because it expresses cytochrome P450 enzymes, transporters, microvilli and enterocytes of identical characteristics to the human small intestine. The FDA recommends this model as integral component of the Biopharmaceutics Classification System (BCS). Most dedicated laboratories use the Caco-2 cell line to screen new chemical entities through prediction of its solubility, bioavailability and the possibility of drug-drug or herb-drug interactions in the gut lumen. However, challenges in the inherent characteristics of Caco-2 cell and inter-laboratory protocol variations have resulted to generation of irreproducible data. These limitations affect the extrapolation of data from pre-clinical research to clinical studies involving drug-drug and herb-drug interactions. This review addresses some of these caveats and enumerates the plausible current and future approaches to reduce the anomalies associated with Caco-2 cell line investigations focusing on its application in herb-drug interactions. PMID:24735758

  2. The change features of the west boundary bifurcation line of the North Equatorial Current in the Pacific

    NASA Astrophysics Data System (ADS)

    Guo, Junru; Liu, Yulong; Song, Jun; Bao, Xianwen; Li, Yan; Chen, Shaoyang; Yang, Jinkun

    2015-12-01

    The equatorial Current in the North Pacific (NEC) is an upper layer westward ocean current, which flows to the west boundary of the ocean, east of the Philippines, and bifurcates into the northerly Kuroshio and the main body of the southerly Mindanao current. Thus, NEC is both the south branch of the Subtropical Circulation and the north branch of the Tropical Circulation. The junction of the two branches extends to the west boundary to connect the bifurcation points forming the bifurcation line. The position of the North Pacific Equatorial Current bifurcation line of the surface determines the exchange between and the distribution of subtropical and tropical circulations, thus affecting the local or global climate. A new identification method to track the line and the bifurcation channel was used in this study, focusing on the climatological characteristics of the western boundary of the North Equatorial Current bifurcation line. The long-term average NEC west boundary bifurcation line shifts northwards with depth. In terms of seasonal variation, the average position of the western boundary of the bifurcation line is southernmost in June and northernmost in December, while in terms of interannual variation, from spring to winter in the years when ENSO is developing, the position of the west boundary bifurcation line of NEC is relatively to the north (south) in EI Niño (La Niña) years as compared to normal years.

  3. A numerical simulation of magnetic reconnection and radiative cooling in line-tied current sheets

    NASA Technical Reports Server (NTRS)

    Forbes, T. G.; Malherbe, J. M.

    1991-01-01

    Radiative MHD equations are used for an optically thin plasma to carry out a numerical experiment related to the formation of 'postflare' loops. The numerical experiment starts with a current sheet that is in mechanical and thermal equilibrium but is unstable to both tearing-mode and thermal-condensation instabilities. The current sheet is line-tied at one end to a photospheric-like boundary and evolves asymmetrically. The effects of thermal conduction, resistivity variation, and gravity are ignored. In general, reconnection in the nonlinear stage of the tearing-mode instability can strongly affect the onset of condensations unless the radiative-cooling time scale is much smaller than the tearing-mode time scale. When the ambient plasma is less than 0.2, the reconnection enters a regime where the outflow from the reconnection region is supermagnetosonic with respect to the fast-mode wave speed. In the supermagnetosonic regime the most rapidly condensing regions occur downstream of a fast-mode shock that forms where the outflow impinges on closed loops attached to the photospheric-like boundary. A similar shock-induced condensation might occur during the formation of 'postflare' loops.

  4. New Identifications of Fe IX, Fe X, Fe XI, Fe XII, and Fe XIII Lines in the Spectrum of Procyon Observed with the Chandra X-Ray Observatory

    NASA Astrophysics Data System (ADS)

    Beiersdorfer, P.; Lepson, J. K.; Desai, P.; Díaz, F.; Ishikawa, Y.

    2014-02-01

    We have analyzed 280 ks of co-added observations performed with Chandra's Low Energy Transmission Grating Spectrometer using theoretical spectra of Fe VIII through Fe XVII. The model spectral data were produced by combining collisional excitation data generated with the Flexible Atomic Code and transition energies generated with a relativistic code based on the multi-reference Møller-Plesset perturbation theory. The spectroscopic accuracy of the theoretical Fe IX wavelengths was ascertained in a comparison with existing laboratory measurements. We find several new Fe IX lines in the 100-140 Å region and confirm two previous identifications. We also have identified a new line from Fe X near 111 Å several weak features near 102 Å may also be ascribed to Fe X. A line near 100.5 Å is identified as originating from Fe XI; a neighboring feature near 101 Å may also be from Fe XI. A cluster of three weak lines between 117 and 118 Å may be ascribed to Fe XII. Two lines near 104 and 106 Å, respectively, have been assigned to Fe XIII. In addition, we confirmed the presence of two out of four Fe VIII lines that were thought to exist in the spectrum. These two lines are located near 131 Å. The Fe IX emission is weakly sensitive to the assumed electron density, while the Fe XIII is strongly dependent on density. We find that a density between 109 and 1010 cm-3 provides the best fit to the Procyon spectrum. We note that several of the new identifications have come at the expense of prior assignments to magnesium or calcium lines, removing evidence for the presence of these elements in this spectral region. No evidence for Fe XVIII, Fe XIX, or Fe XX was found.

  5. Current and Potential Tree Locations in Tree Line Ecotone of Changbai Mountains, Northeast China: The Controlling Effects of Topography

    PubMed Central

    Zong, Shengwei; Wu, Zhengfang; Xu, Jiawei; Li, Ming; Gao, Xiaofeng; He, Hongshi; Du, Haibo; Wang, Lei

    2014-01-01

    Tree line ecotone in the Changbai Mountains has undergone large changes in the past decades. Tree locations show variations on the four sides of the mountains, especially on the northern and western sides, which has not been fully explained. Previous studies attributed such variations to the variations in temperature. However, in this study, we hypothesized that topographic controls were responsible for causing the variations in the tree locations in tree line ecotone of the Changbai Mountains. To test the hypothesis, we used IKONOS images and WorldView-1 image to identify the tree locations and developed a logistic regression model using topographical variables to identify the dominant controls of the tree locations. The results showed that aspect, wetness, and slope were dominant controls for tree locations on western side of the mountains, whereas altitude, SPI, and aspect were the dominant factors on northern side. The upmost altitude a tree can currently reach was 2140 m asl on the northern side and 2060 m asl on western side. The model predicted results showed that habitats above the current tree line on the both sides were available for trees. Tree recruitments under the current tree line may take advantage of the available habitats at higher elevations based on the current tree location. Our research confirmed the controlling effects of topography on the tree locations in the tree line ecotone of Changbai Mountains and suggested that it was essential to assess the tree response to topography in the research of tree line ecotone. PMID:25170918

  6. An Intrinsic Baldwin Effect in the H Beta Broad Emission Line in the Spectrum of NGC 5548

    NASA Technical Reports Server (NTRS)

    Gilbert, Karoline M.; Peterson, Bradley M.

    2003-01-01

    We investigate the possibility of an intrinsic Baldwin effect (i.e., nonlinear emission-line response to continuum variations) in the broad HP emission line of the active galaxy NGC 5548 using crosscorrelation techniques to remove light-travel time effects from the data. We find a nonlinear relationship between the HP emission line and continuum fluxes that is in good agreement with theoretical predictions. We suggest that similar analysis of multiple lines might provide a useful diagnostic of physical conditions in the broad-line region.

  7. Autism Spectrum Disorders and Epigenetics

    ERIC Educational Resources Information Center

    Grafodatskaya, Daria; Chung, Brian; Szatmari, Peter; Weksberg, Rosanna

    2010-01-01

    Objective: Current research suggests that the causes of autism spectrum disorders (ASD) are multifactorial and include both genetic and environmental factors. Several lines of evidence suggest that epigenetics also plays an important role in ASD etiology and that it might, in fact, integrate genetic and environmental influences to dysregulate…

  8. The effect of gradients at stagnation on K-shell x-ray line emission in high-current Ar gas-puff implosions

    SciTech Connect

    Jones, B. Harvey-Thompson, A. J.; Ampleford, D. J.; Jennings, C. A.; Hansen, S. B.; Moore, N. W.; Lamppa, D. C.; Johnson, D.; Jones, M. C.; Waisman, E. M.; Coverdale, C. A.; Cuneo, M. E.; Rochau, G. A.; Apruzese, J. P.; Giuliani, J. L.; Thornhill, J. W.; Ouart, N. D.; Chong, Y. K.; Velikovich, A. L.; Dasgupta, A.; and others

    2015-02-15

    Argon gas puffs have produced 330 kJ ± 9% of x-ray radiation above 3 keV photon energy in fast z-pinch implosions, with remarkably reproducible K-shell spectra and power pulses. This reproducibility in x-ray production is particularly significant in light of the variations in instability evolution observed between experiments. Soft x-ray power measurements and K-shell line ratios from a time-resolved spectrum at peak x-ray power suggest that plasma gradients in these high-mass pinches may limit the K-shell radiating mass, K-shell power, and K-shell yield from high-current gas puffs.

  9. Discovery of a cyclotron absorption line in the spectrum of the binary X-ray pulsar 4U 1538 - 52 observed by Ginga

    NASA Technical Reports Server (NTRS)

    Clark, George W.; Woo, Jonathan W.; Nagase, Fumiaki; Makishima, Kazuo; Sakao, Taro

    1990-01-01

    A cyclotron absorption line near 20 keV has been found in the spectrum of the massive eclipsing binary X-ray pulsar 4U 1538 - 52 in observations with the Ginga observatory. The line is detected throughout the 529 s pulse cycle with a variable equivalent width that has its maximum value during the smaller peak of the two-peak pulse profile. It is found that the profile of the pulse and the phase-dependence of the cyclotron line can be explained qualitatively by a pulsar model based on recent theoretical results on the properties of pencil beams emitted by accretion-heated slabs of magnetized plasma at the magnetic poles of a neutron star. The indicated field at the surface of the neutron star is 1.7 (1 + z) x 10 to the 12th G, where z is the gravitational redshift.

  10. Space and Architecture's Current Line of Research? A Lunar Architecture Workshop With An Architectural Agenda.

    NASA Astrophysics Data System (ADS)

    Solomon, D.; van Dijk, A.

    The "2002 ESA Lunar Architecture Workshop" (June 3-16) ESTEC, Noordwijk, NL and V2_Lab, Rotterdam, NL) is the first-of-its-kind workshop for exploring the design of extra-terrestrial (infra) structures for human exploration of the Moon and Earth-like planets introducing 'architecture's current line of research', and adopting an architec- tural criteria. The workshop intends to inspire, engage and challenge 30-40 European masters students from the fields of aerospace engineering, civil engineering, archi- tecture, and art to design, validate and build models of (infra) structures for Lunar exploration. The workshop also aims to open up new physical and conceptual terrain for an architectural agenda within the field of space exploration. A sound introduc- tion to the issues, conditions, resources, technologies, and architectural strategies will initiate the workshop participants into the context of lunar architecture scenarios. In my paper and presentation about the development of the ideology behind this work- shop, I will comment on the following questions: * Can the contemporary architectural agenda offer solutions that affect the scope of space exploration? It certainly has had an impression on urbanization and colonization of previously sparsely populated parts of Earth. * Does the current line of research in architecture offer any useful strategies for com- bining scientific interests, commercial opportunity, and public space? What can be learned from 'state of the art' architecture that blends commercial and public pro- grammes within one location? * Should commercial 'colonisation' projects in space be required to provide public space in a location where all humans present are likely to be there in a commercial context? Is the wave in Koolhaas' new Prada flagship store just a gesture to public space, or does this new concept in architecture and shopping evolve the public space? * What can we learn about designing (infra-) structures on the Moon or any other

  11. Lines

    ERIC Educational Resources Information Center

    Mires, Peter B.

    2006-01-01

    National Geography Standards for the middle school years generally stress the teaching of latitude and longitude. There are many creative ways to explain the great grid that encircles our planet, but the author has found that students in his college-level geography courses especially enjoy human-interest stories associated with lines of latitude…

  12. Some features of the radial-velocity variations of lines of different intensity in the spectrum of HD 93521. Variability of the stellar wind

    NASA Astrophysics Data System (ADS)

    Rzaev, A. Kh.

    2007-12-01

    CCD spectra taken with the PFES echelle spectrograph of the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences are used to perform a detailed study of the variability of the profiles of Hell, H β, and H α lines in the spectrum of HD 93521. The pattern and nature of the variability of the Hell lines are similar to those of weak HeI lines and are due to nonradial pulsations. The period and amplitude of the radial-velocity variations are the same for the blue and red halves of the absorption profile but their phases are opposite. The behavior of the variations of H β and H α hydrogen lines relative to their mean profiles is the same as that of strong HeI line and is due to nonradial pulsations. The period and phase of the radial-velocity oscillations are the same for the blue and red halves of the absorption profile but their amplitude are different. The behavior of the radial-velocity variations of the absorption and emission components of the H α line indicates that the latter also are caused by nonradial pulsations. All this is indicative of the complex structure of the stellar wind in the region of its origin. The behavior of variability and wind kinematics differ in different directions and for different regions of the atmosphere and/or envelope.

  13. A Relativistic Fe Kα Emission Line in the Intermediate-Luminosity BeppoSAX Spectrum of the Galactic Microquasar V4641 Sgr

    NASA Astrophysics Data System (ADS)

    Miller, J. M.; Fabian, A. C.; in't Zand, J. J. M.; Reynolds, C. S.; Wijnands, R.; Nowak, M. A.; Lewin, W. H. G.

    2002-09-01

    Broad Fe Kα emission lines have recently been reported in a number of Galactic black holes. Such lines are useful accretion flow diagnostics because they may be produced at the inner accretion disk and shaped by relativistic effects, but in general they have been observed only at luminosities of LX~1037-1038 ergs s-1 in soft X-rays. The Galactic microquasar V4641 Sgr-widely known for its 12.2 Crab (1.5-12 keV) outburst in 1999 September-displayed low-level activity in 1999 March. BeppoSAX observed the source in this state, and Fe Kα line emission was found by in 't Zand et al. In reanalyzing these data, we find strong evidence that the Fe Kα line profile is broadened. For the most likely values of the source distance and black hole mass measured by Orosz et al., our fits to the total spectrum indicate that the source was observed at a luminosity of LX=1.9+1.0-0.8×1036 ergs s-1 (2-10 keV), or LX/LEdd=1.8+0.9- 0.8×10-3. Advection-dominated accretion flow models predict a radially recessed disk in this regime. In contrast, fits to the observed Fe Kα emission-line profile with a relativistic line model constrain the inner disk to be consistent with the marginally stable circular orbit of a Schwarzschild black hole.

  14. Elucidating the cancer-specific genetic alteration spectrum of glioblastoma derived cell lines from whole exome and RNA sequencing

    PubMed Central

    Somasundaram, Kumaravel

    2015-01-01

    Cell lines derived from tumor tissues have been used as a valuable system to study gene regulation and cancer development. Comprehensive characterization of the genetic background of cell lines could provide clues on novel genes responsible for carcinogenesis and help in choosing cell lines for particular studies. Here, we have carried out whole exome and RNA sequencing of commonly used glioblastoma (GBM) cell lines (U87, T98G, LN229, U343, U373 and LN18) to unearth single nucleotide variations (SNVs), indels, differential gene expression, gene fusions and RNA editing events. We obtained an average of 41,071 SNVs out of which 1,594 (3.88%) were potentially cancer-specific. The cell lines showed frequent SNVs and indels in some of the genes that are known to be altered in GBM- EGFR, TP53, PTEN, SPTA1 and NF1. Chromatin modifying genes- ATRX, MLL3, MLL4, SETD2 and SRCAP also showed alterations. While no cell line carried IDH1 mutations, five cell lines showed hTERT promoter activating mutations with a concomitant increase in hTERT transcript levels. Five significant gene fusions were found of which NUP93-CYB5B was validated. An average of 18,949 RNA editing events was also obtained. Thus we have generated a comprehensive catalogue of genetic alterations for six GBM cell lines. PMID:26496030

  15. Comparing Symptoms of Autism Spectrum Disorders Using the Current "DSM-IV-TR" Diagnostic Criteria and the Proposed "DSM-V" Diagnostic Criteria

    ERIC Educational Resources Information Center

    Worley, Julie A.; Matson, Johnny L.

    2012-01-01

    The American Psychiatric Association has proposed major revisions for the diagnostic category encompassing Autism Spectrum Disorders (ASD), which will reportedly increase the specificity and maintain the sensitivity of diagnoses. As a result, the aim of the current study was to compare symptoms of ASD in children and adolescents (N = 208) who met…

  16. Utility of the "Social Communication Questionnaire-Current" and "Social Responsiveness Scale" as Teacher-Report Screening Tools for Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Schanding, G. Thomas, Jr.; Nowell, Kerri P.; Goin-Kochel, Robin P.

    2012-01-01

    Limited research exists regarding the role of teachers in screening for Autism Spectrum Disorders (ASD). The current study examined the use of the "Social Communication Questionnaire" (SCQ) and "Social Responsiveness Scale" (SRS) as completed by parents and teachers about school-age children from the Simons Simplex Collection. Using the…

  17. Study of spread spectrum multiple access systems for satellite communications with overlay on current services: Executive summary

    NASA Technical Reports Server (NTRS)

    Ha, Tri T.; Pratt, Timothy

    1987-01-01

    Two different methods of generating spread spectrum signals for an overlay service are discussed, and the data rate and efficiency which can be achieved while maintaining low interference with existing traffic are examined.

  18. Cathodoluminescence Spectrum Imaging Software

    Energy Science and Technology Software Center (ESTSC)

    2011-04-07

    The software developed for spectrum imaging is applied to the analysis of the spectrum series generated by our cathodoluminescence instrumentation. This software provides advanced processing capabilities s such: reconstruction of photon intensity (resolved in energy) and photon energy maps, extraction of the spectrum from selected areas, quantitative imaging mode, pixel-to-pixel correlation spectrum line scans, ASCII, output, filling routines, drift correction, etc.

  19. Absolute integrated intensity and individual line parameters for the 6.2-micron band of NO2. [in solar spectrum

    NASA Technical Reports Server (NTRS)

    Goldman, A.; Bonomo, F. S.; Williams, W. J.; Murcray, D. G.; Snider, D. E.

    1975-01-01

    The absolute integrated intensity of the 6.2-micron band of NO2 at 40 C was determined from quantitative spectra at about 10 per cm resolution by the spectral band model technique. A value of 1430 plus or minus 300 per sq cm per atm was obtained. Individual line parameters, positions, intensities, and ground-state energies were derived, and line-by-line calculations were compared with the band model results and with the quantitative spectra obtained at about 0.5 per cm resolution.

  20. MMS observations of electron-scale filamentary currents in the reconnection exhaust and near the X line

    NASA Astrophysics Data System (ADS)

    Phan, T. D.; Eastwood, J. P.; Cassak, P. A.; Øieroset, M.; Gosling, J. T.; Gershman, D. J.; Mozer, F. S.; Shay, M. A.; Fujimoto, M.; Daughton, W.; Drake, J. F.; Burch, J. L.; Torbert, R. B.; Ergun, R. E.; Chen, L. J.; Wang, S.; Pollock, C.; Dorelli, J. C.; Lavraud, B.; Giles, B. L.; Moore, T. E.; Saito, Y.; Avanov, L. A.; Paterson, W.; Strangeway, R. J.; Russell, C. T.; Khotyaintsev, Y.; Lindqvist, P. A.; Oka, M.; Wilder, F. D.

    2016-06-01

    We report Magnetospheric Multiscale observations of macroscopic and electron-scale current layers in asymmetric reconnection. By intercomparing plasma, magnetic, and electric field data at multiple crossings of a reconnecting magnetopause on 22 October 2015, when the average interspacecraft separation was ~10 km, we demonstrate that the ion and electron moments are sufficiently accurate to provide reliable current density measurements at 30 ms cadence. These measurements, which resolve current layers narrower than the interspacecraft separation, reveal electron-scale filamentary Hall currents and electron vorticity within the reconnection exhaust far downstream of the X line and even in the magnetosheath. Slightly downstream of the X line, intense (up to 3 μA/m2) electron currents, a super-Alfvénic outflowing electron jet, and nongyrotropic crescent shape electron distributions were observed deep inside the ion-scale magnetopause current sheet and embedded in the ion diffusion region. These characteristics are similar to those attributed to the electron dissipation/diffusion region around the X line.

  1. High-voltage overhead power lines in epidemiology: patterns of time variations in current load and magnetic fields.

    PubMed

    Reitan, J B; Tynes, T; Kvamshagen, K A; Vistnes, A I

    1996-01-01

    In epidemiological studies of electromagnetic fields and health effects, exposure classification is crucial. There is no generally accepted biophysical interaction mechanism, but many studies are based on the hypothesis of a causal relationship with the strength of magnetic field. Some definition of the magnitude of exposure must be used, e.g., mean magnetic flux density, the integral of magnetic flux and time, or a peak value. Magnetic fields around a particular power line depend on the current load. The aim of the present study was to follow variations in line current load in the power supply system of the largest Norwegian city on a yearly, monthly, daily and diurnal basis. Fairly large variations in load were found, but increases in consumption were not necessarily reflected in current load on high voltage lines. The correlation between outdoor temperature and current load varied widely, depending on the type of power station feeding the line in question. The registered time variations are large enough to interfere with epidemiological classification of residences and testing of epidemiological hypotheses. PMID:8809360

  2. The 13CH4 absorption spectrum in the Icosad range (6600-7692 cm-1) at 80 K and 296 K: Empirical line lists and temperature dependence

    NASA Astrophysics Data System (ADS)

    Campargue, A.; Béguier, S.; Zbiri, Y.; Mondelain, D.; Kassi, S.; Karlovets, E. V.; Nikitin, A. V.; Rey, M.; Starikova, E. N.; Tyuterev, Vl. G.

    2016-08-01

    The 13CH4 absorption spectrum has been recorded at 296 K and 80 K in the Icosad range between 6600 and 7700 cm-1. The achieved noise equivalent absorption of the spectra recorded by differential absorption spectroscopy (DAS) is about αmin ≈ 1.5 × 10-7 cm-1. Two empirical line lists were constructed including 17,792 and 24,139 lines at 80 K and 296 K, respectively. For comparison, the HITRAN database provides only 1040 13CH4 lines in the region determined from methane spectra with natural isotopic abundance. Empirical values of the lower state energy level, Eemp, were systematically derived from the intensity ratios of the lines measured at 80 K and 296 K. Overall 10,792 Eemp values were determined providing accurate temperature dependence for most of the 13CH4 absorption in the region (93% and 82% at 80 K and 296 K, respectively). The quality of the derived empirical values of the lower state rotational quantum number, Jemp, is illustrated by their clear propensity to be close to an integer. A good agreement is achieved between our small Jemp values, with previous accurate determinations obtained by applying the 2T method to jet and 80 K spectra. The line lists at 296 K and 80 K which are provided as Supplementary material will be used for future rovibrational assignments based on accurate variational calculations.

  3. Instability, Turbulence, and 3D Magnetic Reconnection in a Line-Tied, Zero Net Current Screw Pinch

    NASA Astrophysics Data System (ADS)

    Brookhart, Matthew I.; Stemo, Aaron; Zuberbier, Amanda; Zweibel, Ellen; Forest, Cary B.

    2015-04-01

    This Letter reports the first experimental investigation into a line-tied plasma with a reversed current profile. Discrete current sources create a cylindrical plasma equilibrium with an axial field and zero net current. Detailed magnetic measurements show that an internal m =1 mode with no external character grows exponentially. The nonlinear evolution of the mode drives 3D reconnection events that reorganize the plasma equilibrium. The plasma is turbulent and exhibits reconnection events on a range of scales. These data are consistent with recent simulations of coronal loops and the nanoflare coronal heating mechanism.

  4. ExoMol line lists - IV. The rotation-vibration spectrum of methane up to 1500 K

    NASA Astrophysics Data System (ADS)

    Yurchenko, Sergei N.; Tennyson, Jonathan

    2014-05-01

    A new hot line list is calculated for 12CH4 in its ground electronic state. This line list, called 10to10, contains 9.8 billion transitions and should be complete for temperatures up to 1500 K. It covers the wavelengths longer than 1 μm and includes all transitions to upper states with energies below hc · 18 000 cm-1 and rotational excitation up to J = 39. The line list is computed using the eigenvalues and eigenfunctions of CH4 obtained by variational solution of the Schrödinger equation for the rotation-vibration motion of nuclei employing program TROVE and a new `spectroscopic' potential energy surface (PES) obtained by refining an ab initio PES (CCSD(T)-F12c/aug-cc-pVQZ) through least-squares fitting to the experimentally derived energies with J = 0-4 and a previously reported ab initio dipole moment surface (CCSD(T)-F12c/aug-cc-pVTZ). Detailed comparisons with other available sources of methane transitions including HITRAN, experimental compilations and other theoretical line lists show that these sources lack transitions both higher temperatures and near-infrared wavelengths. The 10to10 line list is suitable for modelling atmospheres of cool stars and exoplanets. It is available from the CDS data base as well as at www.exomol.com.

  5. Discovery of the double Doppler-shifted emission-line systems in the X-ray spectrum of SS 433

    NASA Technical Reports Server (NTRS)

    Kotani, Taro; Kawai, Nobuyuki; Aoki, Takashi; Doty, John; Matsuoka, Masaru; Mitsuda, Kazuhisa; Nagase, Fumiaki; Ricker, George; White, Nick E.

    1994-01-01

    We have used the CCD X-ray spectrometers on ASCA and resolved the X-ray emission line from the jet of SS 433 both into Doppler-shifted components with two distinct velocities, and into emission from different ionization states of iron, i.e., Fe XXV and Fe XXVI. This is the first direct detection of the two Doppler shifted beams in the X-ray spectra of SS 433 and allows the radial velocity of the jet along the line of sight to be determined with an accuracy comparable to the optical spectroscopy. We also found pairs of emission lines from other atomic species, such as ionized silicon and sulfur, with the Doppler shifts consistent with each other. This confirms the origin of the X-ray emission in the high temperature plasma in the jets.

  6. Numerical simulation of current experimental 100 Gbit s{sup -1} DWDM communication lines

    SciTech Connect

    Yushko, O V; Redyuk, A A; Fedoruk, M P; Nanii, O E; Treshchikov, V N

    2015-01-31

    We report the results of experimental and numerical studies of the maximum length of multi-span DP-QPSK DWDM communication lines (channel rate of 100 Gbit s{sup -1}) with 100-kmlong uniform and combined spans. The use of the combined spans (50 km of SSMF fibre and 50 km of NZDSF fibre) has allowed the maximum line length to be increased up to 6700 km, which is 60% higher than in the case of homogeneous SSMF- and NZDSF-based spans. (optical transmission of information)

  7. ExoMol molecular line lists - XVI. The rotation-vibration spectrum of hot H2S

    NASA Astrophysics Data System (ADS)

    Azzam, Ala'a. A. A.; Tennyson, Jonathan; Yurchenko, Sergei N.; Naumenko, Olga V.

    2016-08-01

    This work presents the AYT2 line list: a comprehensive list of 114 million $^{1}$H$_2$$^{32}$S vibration-rotation transitions computed using an empirically-adjusted potential energy surface and an {\\it ab initio} dipole moment surface. The line list gives complete coverage up to 11000 \\cm\\ (wavelengths longer than 0.91 $\\mu$m) for temperatures up to 2000 K. Room temperature spectra can be simulated up to 20000 \\cm\\ (0.5 $\\mu$m) but the predictions at visible wavelengths are less reliable. AYT2 is made available in electronic form as supplementary data to this article and at \\url{www.exomol.com}.

  8. ExoMol molecular line lists - XVI. The rotation-vibration spectrum of hot H2S

    NASA Astrophysics Data System (ADS)

    Azzam, Ala'a. A. A.; Tennyson, Jonathan; Yurchenko, Sergei N.; Naumenko, Olga V.

    2016-08-01

    This work presents the AYT2 line list: a comprehensive list of 115 million 1H232S vibration-rotation transitions computed using an empirically adjusted potential energy surface and an ab initio dipole moment surface. The line list gives complete coverage up to 11 000 cm-1 (wavelengths longer than 0.91 μm) for temperatures up to 2000 K. Room temperature spectra can be simulated up to 20 000 cm-1 (0.5 μm) but the predictions at visible wavelengths are less reliable. AYT2 is made available in electronic form as supplementary data to this paper at www.exomol.com.

  9. Transient analysis and control of bias magnetic state in the transformer of on-line pulse-width-modulation switching full bridge direct current-direct current converter

    NASA Astrophysics Data System (ADS)

    Chen, Jiaxin; Guo, Youguang; Zhu, Jianguo; Wei Lin, Zhi

    2012-04-01

    This paper presents a finite element analysis (FEA) based method for analyzing and controlling the bias magnetic state of the transformer of a pulse-width-modulation (PWM) switching full bridge dc-dc converter. A field-circuit indirect coupling method for predicting the transient bias magnetic state is introduced first. To increase flexibility of the proposed method, a novel transformer model which can address not only its basic input-output characteristic, but also the nonlinear magnetizing inductance, is proposed. Both the asymmetric characteristic and the variable laws of the current flowing through the two secondary windings during the period of PWM switching-off state are highlighted. Finally, the peak magnetizing current controlled method based on the on-line magnetizing current computation is introduced. Analysis results show that this method can address the magnetic saturation at winding ends, and hence many previous difficulties, such as the start-up process and asymmetry of power electronics, can be easily controlled.

  10. Measurement of ion current density at ground level in the vicinity of high voltage DC transmission lines

    NASA Astrophysics Data System (ADS)

    McKnight, R. H.; Kotter, F. R.; Misakian, M.

    1981-12-01

    Sensors for measuring vertical current density at ground level near high voltage dc (HVDC) transmission lines are subject to error when the sensor is not in the ground plane. The magnitude of this error, for guarded and unguarded sensors, was investigated using both dc electric fields with space charge and ac electric fields in a parallel plate facility. For conditions like those expected under HVDC transmission lines, the results obtained using ac and dc methods agreed to within experimental uncertainty. The measured errors are as large as 25 percent for guarded sensors and significantly larger for unguarded sensors. Graphs of data for various sensor elevations and guarding are presented.

  11. Screening and Early Identification of Autism Spectrum Disorders. Updated. Queries: An Occasional Paper Compiling States' Approaches to Current Topics

    ERIC Educational Resources Information Center

    Shaw, Evelyn, Comp.; Hatton, Deborah, Comp.

    2009-01-01

    In response to interest from the National Professional Development Center on Autism Spectrum Disorders (NPDC-ASD), National Early Childhood Technical Assistance Center (NECTAC) queried state Part C and Section 619 coordinators regarding screening measures, diagnostic instruments and procedures, and trends in identifying young children with ASD…

  12. Screening and Early Identification of Autism Spectrum Disorders. Queries: An Occasional Paper Compiling States' Approaches to Current Topics

    ERIC Educational Resources Information Center

    Shaw, Evelyn, Comp.; Hatton, Deborah, Comp.

    2009-01-01

    In response to interest from the National Professional Development Center on Autism Spectrum Disorders (NPDC-ASD), NECTAC (National Early Childhood Technical Assistance Center) queried Part C and Section 619 Coordinators regarding screening measures, diagnostic instruments and procedures, and trends in identifying young children with ASD under the…

  13. Variations of the high-level Balmer line spectrum of the helium-strong star σ Orionis E

    NASA Astrophysics Data System (ADS)

    Smith, M. A.; Bohlender, D. A.

    2007-12-01

    Using the high-level Balmer lines and continuum, we trace the density structure of two magnetospheric disk segments of the prototypical Bp star σ Orionis E (B2p) as these segments occult portions of the star during the rotational cycle. High-resolution spectra of the Balmer lines ≥H9 and Balmer edge were obtained on seven nights in January-February 2007 at an average sampling of 0.01 cycles. We measured equivalent width variations due to the star occultations by two disk segments 0.4 cycles apart and constructed differential spectra of the migrations of the corresponding absorptions across the Balmer line profiles. We first estimated the rotational and magnetic obliquity angles. We then simulated the observed Balmer jump variation using the model atmosphere codes synspec/circus and evaluated the disk geometry and gas thermodynamics. We find that the two occultations are caused by two disk segments. The first of these transits quickly, indicating that the segment resides in a range of distances, perhaps 2.5-6 R*, from the star. The second consists of a more slowly moving segment situated closer to the surface and causing two semi-resolved absorbing maxima. During its transit this segment brushes across the star's “lower” limb. Judging from the line visibility up to H23-H24 during the occultations, both disk segments have mean densities near 1012 cm-3 and are opaque in the lines and continuum. They have semiheights less than 1/2 R*, and their temperatures are near 10 500 K and 12 000 K, respectively. In all, the disks of Bp stars have a much more complicated geometry than has been anticipated, as evidenced by their (sometimes) non-coplanarity, de-centerness, and from star to star, differences in disk height. Based on observations obtained at the the Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, National Research Council of Canada.

  14. Spectrum and density of neutron flux in the irradiation beam line no. 3 of the IBR-2 reactor

    NASA Astrophysics Data System (ADS)

    Shabalin, E. P.; Verkhoglyadov, A. E.; Bulavin, M. V.; Rogov, A. D.; Kulagin, E. N.; Kulikov, S. A.

    2015-03-01

    Methodology and results of measuring the differential density of the neutron flux in irradiation beam line no. 3 of the IBR-2 reactor using neutron activation analysis (NAA) are presented in the paper. The results are compared to the calculation performed on the basis of the 3D MCNP model. The data that are obtained are required to determine the integrated radiation dose of the studied samples at various distances from the reactor.

  15. TESTING THE NO-HAIR THEOREM WITH OBSERVATIONS IN THE ELECTROMAGNETIC SPECTRUM. IV. RELATIVISTICALLY BROADENED IRON LINES

    SciTech Connect

    Johannsen, Tim; Psaltis, Dimitrios

    2013-08-10

    According to the no-hair theorem, astrophysical black holes are fully characterized by their masses and spins and are described by the Kerr metric. This theorem can be tested observationally by measuring (at least) three different multipole moments of the spacetimes of black holes. In this paper, we calculate the profiles of fluorescent iron lines emitted from the accretion flows around black hole candidates within a framework that allows us to perform the calculation as a function of its mass and spin as well as of a free parameter that measures potential deviations from the Kerr metric. We show that such deviations lead to line profiles that are significantly altered and may exhibit a modified flux ratio of the two peaks in their characteristic double-peaked shape. We also show that the disk inclination can be measured independently of the spin and the deviation parameter at low to intermediate inclination angles, as in the case of Kerr black holes. We estimate the precision that near-future X-ray missions such as Astro-H and ATHENA+ are required to achieve in order to resolve deviations from the Kerr metric in iron line profiles and show that constraints on such deviations will be strongest for rapidly spinning black holes. More generally, we show that measuring the line profile with a precision of {approx}5% at disk inclinations of 30 Degree-Sign or 60 Degree-Sign constrains the deviation parameter to order unity for values of the spin a {approx}> 0.5M.

  16. ExoMol line lists - VII. The rotation-vibration spectrum of phosphine up to 1500 K

    NASA Astrophysics Data System (ADS)

    Sousa-Silva, Clara; Al-Refaie, Ahmed F.; Tennyson, Jonathan; Yurchenko, Sergei N.

    2015-01-01

    A comprehensive hot line list is calculated for 31PH3 in its ground electronic state. This line list, called SAlTY, contains almost 16.8 billion transitions between 7.5 million energy levels and it is suitable for simulating spectra up to temperatures of 1500 K. It covers wavelengths longer than 1 μm and includes all transitions to upper states with energies below hc × 18 000 cm-1 and rotational excitation up to J = 46. The line list is computed by variational solution of the Schrödinger equation for the rotation-vibration motion employing the nuclear-motion program TROVE. A previously reported ab initio dipole moment surface is used as well as an updated `spectroscopic' potential energy surface, obtained by refining an existing ab initio surface through least-squares fitting to the experimentally derived energies. Detailed comparisons with other available sources of phosphine transitions confirms SAlTY's accuracy and illustrates the incompleteness of previous experimental and theoretical compilations for temperatures above 300 K. Atmospheric models are expected to severely underestimate the abundance of phosphine in disequilibrium environments, and it is predicted that phosphine will be detectable in the upper troposphere of many substellar objects. This list is suitable for modelling atmospheres of many astrophysical environments, namely carbon stars, Y dwarfs, T dwarfs, hot Jupiters and Solar system gas giant planets. It is available in full from the Strasbourg data centre, CDS, and at www.exomol.com.

  17. The Mg II h and k interstellar lines in the spectrum of the G-type giant HD 156854

    NASA Technical Reports Server (NTRS)

    Gurzadian, G. A.; Cholakian, V. G.; Kondo, Y.; Shore, Steven N.; Terzian, Yervant

    1990-01-01

    The results of the measurements and analysis of the IUE observations of the 2800 Mg II doublet in the spectrum of HD 156854, a G9 III star, are presented. The relative power of the magnesium chromosphere, R(Mg) = 0.00001, is in agreement with the known data for giants of the same class. The emission profiles of this doublet present absorption cores, which are of interstellar origin. Taking into account the interstellar depletion of Mg, the derived density of interstellar hydrogen is n(H) = 0.001/cu cm, which agrees with the conclusion (Paresce 1984) about the possibility of large hydrogen concentrations in some directions of the Galaxy far from the sun.

  18. A Method of Producing High-Quality Linear Field Gradient for Magnetic Resonance Imaging Using Straight Current Lines

    NASA Astrophysics Data System (ADS)

    Furusawa, Masahiro; Ikeya, Motoji

    1991-09-01

    A new method for generating a highly linear field gradient in a large space is described. The coil system consists of N equispaced parallel current lines placed on a cylinder perpendicular to the static magnetic field. The wires generate a gradient of any accuracy depending on N and in any direction in a plane perpendicular to the cylinder axis by controlling the current of each wire independently. The accuracy of the gradient using 16 infinite-length wires is less than 0.3% in the 60% region in diameter of the cylinder. An ESR-CT image of a DPPH test sample was obtained using this system of 16 wires.

  19. The onset of shear modes in the high frequency spectrum of simple disordered systems: Current knowledge and perspectives

    DOE PAGESBeta

    Cunsolo, Alessandro; Suvorov, Alexey; Cai, Yong Q.

    2015-10-20

    In this study, nearly two decades of thorough Inelastic X Ray Scattering (IXS) studies of transverse-like excitation in the spectrum simple amorphous materials are reviewed. A particular attention is given to the case of liquid water and other prototypical samples, through a discussion of both solved and still open issues. Finally, the perspectives opened up by the development of next generation IXS instruments with unprecedented contrast and resolution bandwidth are briefly illustrated.

  20. A search variability in the UV spectrum of Pi Aquarii and Fe 3 shell lines of Be stars

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Several short U1 and U2 observations of Be stars are obtained with the Copernicus satellite. Pi Aquarii (B1 IV-Ve) is observed with the U1 and U2 spectrometers. These scans are compared with earlier observations. Variations in the strengths and profiles of selected shell and photospheric features are examined. In order to study possible changes in the temperature of the circumstellar envelope, features covering a wide range in ionization are observed. Included in the observing program are lines of O VI, N V, Si IV, Si III, S III, Fe III, and N I.

  1. Ultraviolet polarimeter to record resonance-line polarization in the solar spectrum around 130-150 nm.

    PubMed

    Stenflo, J O; Biverot, H; Stenmark, L

    1976-05-01

    A Swedish-built uv spectropolarimeter to be launched on a Soviet satellite in the Intercosmos series is described. The scientific objective is to record linear polarization across monochromatic solar images formed in resonance lines in the 130-150-nm wavelength region. This polarization arises by coherent scattering in the chromosphere-corona transition region of the sun. The instrument uses two parallel optical channels with highly different polarizing properties. The polarization analysis is done by reflection at gold-coated mirrors. The uv calibrations of the two flight models are described. PMID:20165149

  2. Manipulation of superparamagnetic beads using on-chip current lines placed on a ferrite magnet

    NASA Astrophysics Data System (ADS)

    Wang, Z. H.; Lew, W. S.; Bland, J. A. C.

    2006-04-01

    Manipulation of superparamagnetic beads in a static solution is demonstrated using on-chip current striplines placed on a ferrite magnet. The ferrite magnet fits the requirement to enhance the bead's magnetic moment while still keeping beads randomly dispersed in the liquid, so allowing easy and selective manipulation of single beads. By applying currents up to hundreds of milliampere, the tapered stripline first attracts the beads to its edge, then the magnetic force along the edge drives the trapped beads moving continuously towards the chip center. On arriving into the chip central area (a square zone which acts as a site to collect the arriving beads), fine manipulation of selected single beads is further performed by switching on/off and/or tuning the current passing through the nearby quadruple striplines. We suggest that the present system may provide a simple but effective platform for handling magnetic tags for biological and biomedical applications.

  3. The discovery of an O VII emission line in the ASCA spectrum of the Seyfert galaxy NGC 3783

    NASA Technical Reports Server (NTRS)

    George, I. M.; Turner, T. J.; Netzer, H.

    1995-01-01

    We report the first observation of an O VII 0.57 keV emission line in a Seyfert 1 galaxy. NGC 3783 was observed by ASCA twice over a period of 4 days in 1993 December. The source exhibited a approximately 30% change in intensity between the two observations, with most of the variability taking place as a result of steepening of the continuum less than or approximately equal to 1 keV. Spectra from both observations show intense absorption features in the 0.5-1.5 keV band, which can be well fitted by an ionized absorber model of solar composition, column density of 10(exp 22.2)/sq cm and ionization parameter of approximately 7-8; the strongest absorption features being due to O VII and O VIII. Two emission features are also seen in the spectra which we identify as O VII 0.57 keV (equivalent width approximately equals 36 eV) and O VIII 0.65 keV (equivalent width approximately equals 11 eV). We also show that the 3-6 keV continuum of the source is well fitted by a Gamma = 1.3-1.4 power-law continuum, a narrow neutral iron K-shell fluorescence line and a strong iron K-shell absorption edge, possibly corresponding to highly ionized iron.

  4. A study of the continuum flux and the line structure in the IUE spectrum of Beta Lyrae

    NASA Astrophysics Data System (ADS)

    Aydin, C.; Brandi, E.; Engin, S.; Ferrer, O. E.; Hack, M.; Sahade, J.; Solivella, G.; Yilmaz, N.

    1988-03-01

    A study of the available archival IUE images of Beta Lyrae has led to the following results: (1) for lambda in the range of 1250 - 1500 A, the eclipse depth at second conjunction is slightly larger than the eclipse depth at primary conjunction; they are equal at about 1670 A; (2) the profiles of the resonance lines of SiIV (and the same seems to be true for NV and CIV) can be described as composite, formed by the superposition of a stationary P Cygni profile that suggests a velocity of approach of -170 km/s and a broad, less strong, emission that seems to yield a velocity distribution in antiphase with the velocity curve of the B8 II component of the system; and (3) the emission lines of the intercombination doublet of semiforbidden N II at about 2140 A suggest a velocity of about -130 km/s. The interpretation of the latter composite profile appears similar to the one suggested by Sahade (1966) to describe H-alpha and He I 5876 and He I 6678, and by Batten and Sahade (1973) to describe H-alpha.

  5. A study of the continuum flux and the line structure in the IUE spectrum of Beta Lyrae

    NASA Technical Reports Server (NTRS)

    Aydin, C.; Engin, S.; Brandi, E.; Ferrer, O. E.; Hack, M.

    1988-01-01

    A study of the available archival IUE images of Beta Lyrae has led to the following results: (1) for lambda in the range of 1250 - 1500 A, the eclipse depth at second conjunction is slightly larger than the eclipse depth at primary conjunction; they are equal at about 1670 A; (2) the profiles of the resonance lines of SiIV (and the same seems to be true for NV and CIV) can be described as composite, formed by the superposition of a stationary P Cygni profile that suggests a velocity of approach of -170 km/s and a broad, less strong, emission that seems to yield a velocity distribution in antiphase with the velocity curve of the B8 II component of the system; and (3) the emission lines of the intercombination doublet of semiforbidden N II at about 2140 A suggest a velocity of about -130 km/s. The interpretation of the latter composite profile appears similar to the one suggested by Sahade (1966) to describe H-alpha and He I 5876 and He I 6678, and by Batten and Sahade (1973) to describe H-alpha.

  6. Improvement in operational characteristics of KEPCO’s line-commutation-type superconducting hybrid fault current limiter

    NASA Astrophysics Data System (ADS)

    Yim, S.-W.; Park, B.-C.; Jeong, Y.-T.; Kim, Y.-J.; Yang, S.-E.; Kim, W.-S.; Kim, H.-R.; Du, H.-I.

    2013-01-01

    A 22.9 kV class hybrid fault current limiter (FCL) developed by Korea Electric Power Corporation and LS Industrial Systems in 2006 operates using the line commutation mechanism and begins to limit the fault current after the first half-cycle. The first peak of the fault current is available for protective coordination in the power system. However, it also produces a large electromagnetic force and imposes a huge stress on power facilities such as the main transformer and gas-insulated switchgear. In this study, we improved the operational characteristics of the hybrid FCL in order to reduce the first peak of the fault current. While maintaining the structure of the hybrid FCL system, we developed a superconducting module that detects and limits the fault current during the first half-cycle. To maintain the protective coordination capacity, the hybrid FCL was designed to reduce the first peak value of the fault current by up to approximately 30%. The superconducting module was also designed to produce a minimum AC loss, generating a small, uniform magnetic field distribution during normal operation. Performance tests confirmed that when applied to the hybrid FCL, the superconducting module showed successful current limiting operation without any damage.

  7. Effect of Current Sheets on the Solar Wind Magnetic Field Power Spectrum from the Ulysses Observation: From Kraichnan to Kolmogorov Scaling

    SciTech Connect

    Li, G.; Miao, B.; Hu, Q.; Qin, G.

    2011-03-25

    The MHD turbulence theory developed by Iroshnikov and Kraichnan predicts a k{sup -1.5} power spectrum. Solar wind observations, however, often show a k{sup -5/3} Kolmogorov scaling. Based on 3 years worth of Ulysses magnetic field data where over 28 000 current sheets are identified, we propose that the current sheet is the cause of the Kolmogorov scaling. We show that for 5 longest current-sheet-free periods the magnetic field power spectra are all described by the Iroshnikov-Kraichnan scaling. In comparison, for 5 periods that have the most number of current sheets, the power spectra all exhibit Kolmogorov scaling. The implication of our results is discussed.

  8. Effect of current sheets on the solar wind magnetic field power spectrum from the Ulysses observation: from Kraichnan to Kolmogorov scaling.

    PubMed

    Li, G; Miao, B; Hu, Q; Qin, G

    2011-03-25

    The MHD turbulence theory developed by Iroshnikov and Kraichnan predicts a k(-1.5) power spectrum. Solar wind observations, however, often show a k(-5/3) Kolmogorov scaling. Based on 3 years worth of Ulysses magnetic field data where over 28,000 current sheets are identified, we propose that the current sheet is the cause of the Kolmogorov scaling. We show that for 5 longest current-sheet-free periods the magnetic field power spectra are all described by the Iroshnikov-Kraichnan scaling. In comparison, for 5 periods that have the most number of current sheets, the power spectra all exhibit Kolmogorov scaling. The implication of our results is discussed. PMID:21517318

  9. A summary of current understanding regarding children with autism spectrum disorder who are deaf or hard of hearing.

    PubMed

    Szarkowski, Amy; Mood, Deborah; Shield, Aaron; Wiley, Susan; Yoshinaga-Itano, Christine

    2014-11-01

    This article provides a consensus perspective based on the authors' expertise and the limited available literature regarding our understanding of children with an autism spectrum disorder (ASD) who are deaf or hard of hearing (D/HH). The challenges in the accurate identification of an ASD in children who are D/HH, including red flags for a potential ASD and screening and assessment for ASD, are described in this article. Additionally, strategies to guide professionals in their communication about a possible ASD with families and to frame the need for expanding aspects of communication important for this group of children are suggested. PMID:25321849

  10. The Influence of the Photoionizing Radiation Spectrum on Metal-Line Ratios in Ly(alpha) Forest Clouds

    NASA Technical Reports Server (NTRS)

    Giroux, Mark L.; Shull, J. Michael

    1997-01-01

    Recent measurements of Si IV/C IV ratios in the high-redshift Ly(alpha) forest (Songaila & Cowie, AJ, 112, 335 (1996a); Savaglio et at., A&A (in press) (1997)) have opened a new window on chemical enrichment and the first generations of stars. However, the derivation of accurate Si/C abundances requires reliable ionization corrections, which are strongly dependent on the spectral shape of the metagalactic ionizing background and on the 'local effects' of hot stars in nearby galaxies. Recent models have assumed power-law quasar ionizing backgrounds plus a decrement at 4 Ryd to account for He II attenuation in intervening clouds. However, we show that realistic ionizing backgrounds based on cosmological radiative transfer models produce more complex ionizing spectra between 1-5 Ryd that are critical to interpreting ions of Si and C. We also make a preliminary investigation of the effects of He II ionization front nonoverlap. Because the attenuation and reemission by intervening clouds enhance Si IV relative to C the observed high Si IV/C IV ratios do not require an unrealistic Si overproduction (Si/C greater than or equal to 3 (Si/C)(solar mass)). If the ionizing spectrum is dominated by 'local effects' from massive stars, even larger Si IV/C IV ratios are possible. However, unless stellar radiation dominates quasars by more than a factor of 10, we confirm the evidence for some Si overproduction by massive stars; values Si/C approx. 2(Si/C)(solar mass) fit the measurements better than solar abundances. Ultimately, an adequate interpretation of the ratios of C IV, Si IV, and C II may require hot, collisionally ionized gas in a multiphase medium.

  11. Detection of a cyclotron line with RXTE in the current outburst of EXO2030+375

    NASA Astrophysics Data System (ADS)

    Wilson, Colleen A.; Finger, Mark H.

    2006-08-01

    We have regularly monitored the transient Be/X-ray pulsar EXO 2030+375 with pointed RXTE observations since the beginning of its current giant (type II) outburst. As reported by Corbet & Levine (Atel#843) this outburst began in mid June. The flux rose (see Atel#861 and #868) until the end of July to a count rate of 1600 counts/s per PCU (2-60 keV) and during August it varied substantially around this constant level.

  12. Advances in first-line treatment of chronic lymphocytic leukemia: current recommendations on management and first-line treatment by the German CLL Study Group (GCLLSG).

    PubMed

    Cramer, Paula; Langerbeins, Petra; Eichhorst, Barbara; Hallek, Michael

    2016-01-01

    The management of patients with CLL is undergoing significant changes; during the last decade, the outcome of first-line therapies has been markedly improved with the addition of anti-CD20 antibodies to chemotherapy. Today, chemoimmunotherapy for physically fit patients ≤ 65 years should consist of fludarabine, cyclophosphamide, and rituximab (FCR). The combination of bendamustine and rituximab (BR) should be considered in physically fit patients > 65 years and in patients with a higher risk of infections. Patients with reduced fitness and/or relevant comorbidity should receive chlorambucil with a CD20 antibody, preferably obinutuzumab. Regardless of their fitness, patients with CLL carrying genetic aberrations such as del(17p) and/or TP53 mutation poorly respond to chemoimmunotherapy and therefore require different therapeutic approaches. An increasing understanding of the disease biology has led to the development of targeted drugs for the treatment of CLL, such as the BTK inhibitor ibrutinib and PI3K inhibitor idelalisib. These agents have shown efficacy in high-risk and relapsed/refractory patients and are currently being evaluated in clinical trials for first-line therapy. It is anticipated that these compounds and further other novel agents will profoundly change the therapy of CLL. PMID:26332019

  13. Discovery of a broad spectrum antiproliferative agent with selectivity for DDR1 kinase: cell line-based assay, kinase panel, molecular docking, and toxicity studies.

    PubMed

    Elkamhawy, Ahmed; Park, Jung-Eun; Cho, Nam-Chul; Sim, Taebo; Pae, Ae Nim; Roh, Eun Joo

    2016-01-01

    Herein, we report compound KST9046, a new agent possessing quinazoline-urea scaffold. Preliminary biological evaluation done by the National Cancer Institute (NCI), USA, showed a great inhibitory effect of KST9046 over the 60 cell-line tumor panel. Accordingly, it was selected for a dose-response assay; a broad spectrum antiproliferative activity with GI(50) ranging from 1.3 to 3.9 µM was exerted. To explore a potential kinase inhibitory effect, KST9046 was applied at a single dose of 10 µM against a kinase panel of 347 different enzymes representing >50% of the predicted human protein kinome. Interestingly, selective inhibition of 76% was observed on DDR1 kinase. Further, KST9046 showed an IC(50) value of 4.38 µM for DDR1. A molecular docking model presented KST9046 as a potential type III inhibitor for DDR1 kinase with an allosteric mode of interaction, which may offer an explanation for its selectivity. As further investigation, CYP450 assay was carried out for KST9046, it showed a promising toxicity profile against four different isoforms. Based on these findings, KST9046 can be further evaluated as a promising safe new hit for the development of broad spectrum anticancer agents with a selectivity for DDR1 kinase. PMID:25807298

  14. The field line topology of a uniform magnetic field superposed on the field of a distributed ring current

    SciTech Connect

    Chance, M.S. . Plasma Physics Lab.); Greene, J.M.; Jensen, T.H. )

    1991-07-01

    A magnetic field line topology with nulls, generated by superimposing a uniform magnetic field onto the field from a distributed ring current, is analyzed. This simple model is amenable to substantial analytical progress and also facilitates the visualization of the three dimensional field geometry. Four nulls are seen to exist and representative field lines and tubes of flux found by numerical integration are presented. An infinite number of topologically distinct flux bundles is found. A convenient mapping is defined which proves very useful in distinguishing between and following the paths of the different tubes of flux as they traverse through the null system. The complexities already present in this simple but nontrivial configuration serve to emphasize the difficulties in analyzing more complicated geometries, but the intuition gained from this study proves beneficial in those cases. One such example is the application to a model of plasmoid formations in the earth's magnetotail. 7 refs., 19 figs.

  15. Modified in-line Sagnac interferometer with passive demodulation technique for environmental immunity of a fiber-optic current sensor.

    PubMed

    Lin, H; Lin, W W; Chen, M H

    1999-05-01

    A modified in-line Sagnac interferometer (MISI) with passive demodulation Technique (PDT) was proposed to immunize the fiber-optic current sensor (FOCS) from environmental perturbations. A large vibration to simulate the environmental perturbations with acceleration up to 12 g was applied to the lead fiber of the FOCS. The noise floor could be significantly suppressed (20 dB) by the MISI better than by a conventional interferometer. In the same dynamic environments, the PDT could make the FOCS achieve a good linear demodulation with average distortion rates always lower than 0.9%. In addition, all the sensitivities measured in both static and dynamic environments are all approximately 4.5 microrad/(A(rms) turns), which is close to the literatural data measured in static environments. These considerable achievements of high sensitivity, environmental immunity, and free electric shock concerns may lead FOCS's to field-monitoring applications of power delivery lines. PMID:18319852

  16. MODELING THE QUANTUM INTERFERENCE SIGNATURES OF THE Ba II D{sub 2} 4554 A LINE IN THE SECOND SOLAR SPECTRUM

    SciTech Connect

    Smitha, H. N.; Nagendra, K. N.; Sampoorna, M.; Stenflo, J. O. E-mail: knn@iiap.res.in E-mail: stenflo@astro.phys.ethz.ch

    2013-05-10

    Quantum interference effects play a vital role in shaping the linear polarization profiles of solar spectral lines. The Ba II D{sub 2} line at 4554 A is a prominent example, where the F-state interference effects due to the odd isotopes produce polarization profiles, which are very different from those of the even isotopes that have no F-state interference. It is therefore necessary to account for the contributions from the different isotopes to understand the observed linear polarization profiles of this line. Here we do radiative transfer modeling with partial frequency redistribution (PRD) of such observations while accounting for the interference effects and isotope composition. The Ba II D{sub 2} polarization profile is found to be strongly governed by the PRD mechanism. We show how a full PRD treatment succeeds in reproducing the observations, while complete frequency redistribution alone fails to produce polarization profiles that have any resemblance to the observed ones. However, we also find that the line center polarization is sensitive to the temperature structure of the model atmosphere. To obtain a good fit to the line center peak of the observed Stokes Q/I profile, a small modification of the FALX model atmosphere is needed, by lowering the temperature in the line-forming layers. Because of the pronounced temperature sensitivity of the Ba II D{sub 2} line it may not be a suitable tool for Hanle magnetic-field diagnostics of the solar chromosphere, because there is currently no straightforward way to separate the temperature and magnetic-field effects from each other.

  17. Enhanced lines and box-shaped features in the gamma-ray spectrum from annihilating dark matter in the NMSSM

    NASA Astrophysics Data System (ADS)

    Cerdeño, D. G.; Peiró, M.; Robles, S.

    2016-04-01

    We study spectral features in the gamma-ray emission from dark matter (DM) annihilation in the Next-to-Minimal Supersymmetric Standard Model (NMSSM), with either neutralino or right-handed (RH) sneutrino DM . We perform a series of scans over the NMSSM parameter space, compute the DM annihilation cross section into two photons and the contribution of box-shaped features, and compare them with the limits derived from the Fermi-LAT search for gamma-ray lines using the latest Pass 8 data. We implement the LHC bounds on the Higgs sector and on the masses of supersymmetric particles as well as the constraints on low-energy observables. We also consider the recent upper limits from the Fermi-LAT satellite on the continuum gamma-ray emission from dwarf spheroidal galaxies (dSphs). We show that in the case of the RH sneutrino the constraint on gamma-ray spectral features can be more stringent than the dSph bounds. This is due to the Breit-Wigner enhancement near the ubiquitous resonances with a CP even Higgs and the contribution of scalar and pseudoscalar Higgs final states to box-shaped features. By contrast, for neutralino DM, the di-photon final state is only enhanced in the resonance with a Z boson and box-shaped features are even more suppressed. Therefore, the observation of spectral features could constitute a discriminating factor between both models. In addition, we compare our results with direct DM searches, including the SuperCDMS and LUX limits on the elastic DM-nucleus scattering cross section and show that some of these scenarios would be accessible to next generation experiments. Thus, our findings strengthen the idea of complementarity among distinct DM search strategies.

  18. Experimental study on magnetically insulated transmission line electrode surface evolution process under MA/cm current density

    NASA Astrophysics Data System (ADS)

    Zhang, PengFei; Hu, Yang; Yang, HaiLiang; Sun, Jiang; Wang, Liangping; Cong, Peitian; Qiu, Aici

    2016-03-01

    The design of high-current density magnetically insulated transmission line (MITL) is a difficult problem of current large-scale Z-pinch device. In particular, a thorough understanding of the MITL electrode surface evolution process under high current density is lacking. On the "QiangGuang-I" accelerator, the load area possesses a low inductance short-circuit structure with a diameter of 2.85 mm at the cathode, and three reflux columns with a diameter of 3 mm and uniformly distributed circumference at the anode. The length of the high density MITL area is 20 mm. A laser interferometer is used to assess and analyze the state of the MITL cathode and anode gap, and their evolution process under high current density. Experimental results indicate that evident current loss is not observed in the current density area at pulse leading edge, and peak when the surface current density reaches MA/cm. Analysis on electrode surface working conditions indicates that when the current leading edge is at 71.5% of the peak, the total evaporation of MITL cathode structure can be realized by energy deposition caused by ohmic heating. The electrode state changes, and diffusion conditions are reflected in the laser interferometer image. The MITL cathode area mainly exists in metal vapor form. The metal vapor density in the cathode central region is higher than the upper limit of laser penetration density (˜4 × 1021/cm3), with an expansion velocity of ˜0.96 km/s. The metal vapor density in the electrode outer area may lead to evident distortion of fringes, and its expansion velocity is faster than that in the center area (1.53 km/s).

  19. The Spectrum of VY Canis Majoris in 2000 February

    NASA Astrophysics Data System (ADS)

    Wallerstein, George; Gonzalez, Guillermo

    2001-08-01

    We present the current (2000 February) status of the optical spectrum of the irregularly variable M supergiant VY CMa, based on high-resolution CCD spectra. The emission spectrum is largely unchanged over the past 43 yr, with low-lying atomic lines as well as the molecules TiO and ScO in emission. Tables of observed wavelengths for both identified and unidentified lines are presented.

  20. Is the X-ray spectrum of the narrow emission line QSO PG1211+143 defined by its energetic outflow?

    NASA Astrophysics Data System (ADS)

    Pounds, K. A.; Reeves, J. N.

    2007-01-01

    An XMM-Newton observation of the bright QSO PG1211+143 in 2001 revealed a blueshifted absorption line spectrum indicative of a high-velocity radial outflow of highly ionized gas. Unless highly collimated, the outflow mass rate was shown to be comparable to the accretion rate, with mechanical energy a significant fraction of the bolometric luminosity. Analysis of the full XMM-Newton data set now allows the wider effects of that energetic outflow to be explored. We find that absorption and re-emission of the primary continuum flux in the ionized outflow, together with a second, less strongly absorbed, continuum component can explain the strong `soft excess' in PG1211+143 without the extreme velocity `smearing' in conflict with observed absorption line widths. Previously unpublished data from a second XMM-Newton observation of PG1211+143 is shown to be consistent with the new spectral model, finding that the additional continuum component dominates the spectral variability. We speculate that this variable continuum component is powered by the high-velocity outflow.

  1. AN Fe XXIV ABSORPTION LINE IN THE PERSISTENT SPECTRUM OF THE DIPPING LOW-MASS X-RAY BINARY 1A 1744-361

    SciTech Connect

    Gavriil, Fotis P.; Strohmayer, Tod E.; Bhattacharyya, Sudip

    2012-07-01

    We report on Chandra X-ray Observatory (Chandra) High Energy Transmission Grating spectra of the dipping low-mass X-ray binary 1A 1744-361 during its 2008 July outburst. We find that its persistent emission is well modeled by a blackbody (kT {approx} 1.0 keV) plus power law ({Gamma} {approx} 1.7) with an absorption edge. In the residuals of the combined spectrum, we find a significant absorption line at 6.961 {+-} 0.002 keV, consistent with the Fe XXVI (hydrogen-like Fe) 2-1 transition. We place an upper limit on the velocity of a redshifted flow of v < 221 km s{sup -1}. We find an equivalent width for the line of 27{sup +2}{sub -3} eV, from which we determine a column density of (7 {+-} 1) Multiplication-Sign 10{sup 17} cm{sup -2} via a curve-of-growth analysis. Using XSTAR simulations, we place a lower limit on the ionization parameter of >10{sup 3.6} erg cm s{sup -1}. We discuss what implications the feature has on the system and its geometry. We also present Rossi X-ray Timing Explorer data accumulated during this latest outburst and, via an updated color-color diagram, clearly show that 1A 1744-361 is an 'atoll' source.

  2. THE CM-, MM-, AND SUB-MM-WAVE SPECTRUM OF ALLYL ISOCYANIDE AND RADIOASTRONOMICAL OBSERVATIONS IN ORION KL AND THE SgrB2 LINE SURVEYS

    SciTech Connect

    Haykal, I.; Margulès, L.; Huet, T. R.; Motyienko, R. A.; Écija, P.; Cocinero, E. J.; Basterretxea, F.; Fernández, J. A.; Castaño, F.; Guillemin, J. C.; Tercero, B.; Cernicharo, J.

    2013-11-10

    Organic isocyanides have an interesting astrochemistry and some of these molecules have been detected in the interstellar medium (ISM). However, rotational spectral data for this class of compounds are still scarce. We provide laboratory spectra of the four-carbon allyl isocyanide covering the full microwave region, thus allowing a potential astrophysical identification in the ISM. We assigned the rotational spectrum of the two cis (synperiplanar) and gauche (anticlinal) conformations of allyl isocyanide in the centimeter-wave region (4-18 GHz), resolved its {sup 14}N nuclear quadrupole coupling (NQC) hyperfine structure, and extended the measurements into the millimeter and submillimeter-wave (150-900 GHz) ranges for the title compound. Rotational constants for all the monosubstituted {sup 13}C and {sup 15}N isotopologues are additionally provided. Laboratory observations are supplemented with initial radioastronomical observations. Following analysis of an extensive dataset (>11000 rotational transitions), accurate ground-state molecular parameters are reported for the cis and gauche conformations of the molecule, including rotational constants, NQC parameters, and centrifugal distortion terms up to octic contributions. Molecular parameters have also been obtained for the two first excited states of the cis conformation, with a dataset of more than 3300 lines. The isotopic data allowed determining substitution and effective structures for the title compound. We did not detect allyl isocyanide either in the IRAM 30 m line survey of Orion KL or in the PRIMOS survey toward SgrB2. Nevertheless, we provided an upper limit to its column density in Orion KL.

  3. An Fe XXIV Absorption Line in the Persistent Spectrum of the Dipping Low-Mass X-Ray Binary 1A 1744-361

    NASA Technical Reports Server (NTRS)

    Gavriil, Fotis P.; Strohmayer, Tod E.; Bhattacharyya, Sudip

    2012-01-01

    We report on Chandra X-ray Observatory (Chandra) High Energy Transmission Grating spectra of the dipping low-mass X-ray binary 1A 1744-361 during its 2008 July outburst. We find that its persistent emission is well modeled by a blackbody (kT approx. 1.0 keV) plus power law (Gamma approx. 1.7) with an absorption edge. In the residuals of the combined spectrum, we find a significant absorption line at 6.961 +/- 0.002 keV, consistent with the Fe xxvi (hydrogen-like Fe) 2-1 transition.We place an upper limit on the velocity of a redshifted flow of nu < 221 km/s. We find an equivalent width for the line of 27+2/-3 eV, from which we determine a column density of (7 +/- 1)×10(exp 17) /sq. cm via a curve-of-growth analysis. Using XSTAR simulations, we place a lower limit on the ionization parameter of >103.6 erg cm/s. We discuss what implications the feature has on the system and its geometry. We also present Rossi X-ray Timing Explorer data accumulated during this latest outburst and, via an updated color-color diagram, clearly show that 1A 1744-361 is an "atoll" source

  4. An Fe XXVI Absorption Line in the Persistent Spectrum of the Dipping Low Mass X-ray Binary 1A 1744-361

    NASA Technical Reports Server (NTRS)

    Gavriil, Fotis P.; Strohmayer, Tod E.; Bhattacharyya, Sudip

    2009-01-01

    We report on Chandra X-ray Observatory (CXO) High-Energy Transmission Grating (HETG) spectra of the dipping Low Mass X-ray Binary (LMXB) 1A 1744-361 during its July 2008 outburst. We find that its persistent emission is well modeled by a blackbody (kT approx. 1.0 keV) plus power-law (Gamma approx. 1.7) with an absorption edge at 7.6 keV. In the residuals of the combined spectrum we find a significant absorption line at 6.961+/-0.002 keV, consistent with the Fe XXVI (hydrogen-like Fe) 2 - 1 transition. We place an upper limit on the velocity of a redshifted flow of v < 221 km/s. We find an equivalent width for the line of 27+2/-3 eV, from which we determine a column density of 7+/-1 x 10(exp 17)/sq cm via a curve-of-growth analysis. Using XSTAR simulations, we place a lower limit on the ionization parameter of > 10(exp 3.6) erg cm/s. The properties of this line are consistent with those observed in other dipping LMXBs. Using Rossi X-ray Timing Explorer (RXTE) data accumulated during this latest outburst we present an updated color-color diagram which clearly shows that IA 1744-361 is an "atoll" source. Finally, using additional dips found in the RXTE and CXO data we provide an updated orbital period estimate of 52+/-5 minutes.

  5. Ion and electron dynamics generating the Hall current in the exhaust far downstream of the reconnection x-line

    NASA Astrophysics Data System (ADS)

    Fujimoto, Keizo; Takamoto, Makoto

    2016-01-01

    We have investigated the ion and electron dynamics generating the Hall current in the reconnection exhaust far downstream of the x-line where the exhaust width is much larger than the ion gyro-radius. A large-scale particle-in-cell simulation shows that most ions are accelerated through the Speiser-type motion in the current sheet formed at the center of the exhaust. The transition layers formed at the exhaust boundary are not identified as slow mode shocks. (The layers satisfy mostly the Rankine-Hugoniot conditions for a slow mode shock, but the energy conversion hardly occurs there.) We find that the ion drift velocity is modified around the layer due to a finite Larmor radius effect. As a result, the ions are accumulated in the downstream side of the layer, so that collimated ion jets are generated. The electrons experience two steps of acceleration in the exhaust. The first is a parallel acceleration due to the out-of-plane electric field Ey which has a parallel component in most area of the exhaust. The second is a perpendicular acceleration due to Ey at the center of the current sheet and the motion is converted to the parallel direction. Because of the second acceleration, the electron outflow velocity becomes almost uniform over the exhaust. The difference in the outflow profile between the ions and electrons results in the Hall current in large area of the exhaust. The present study demonstrates the importance of the kinetic treatments for collisionless magnetic reconnection even far downstream from the x-line.

  6. Spectrum analysis of the power line flicker induced by the electrical test of the prototype Booster dipole

    SciTech Connect

    Meth, M.

    1992-07-17

    Testing of the prototype Booster dipole magnet at full current produced measurable disturbances of the beam position at the National Synchrotron Light Source. Power for the magnet and the NSLS are distributed from three substation transformers at Temple Place. Normally the substation configuration is for two independent 13.8 KV buses, derived from the 69 KV LILCO distribution. The buses are connected through a circuit breaker that is normally open circuited. Power for the magnet test is derived from one of the 13.8 KV buses and power for the NSLS is derived from the second bus. Coupling of the pulsating magnet load and the NSLS is at the 69 KV level. However, on the days that the interference was first observed at the NSLS only one-half of the substation transformers at Temple Place were in service. The 13.8 KV tie breaker was closed and the full substation load was supplied from this common bus. Thus the coupling between the pulsating magnet load and the NSLS was at the 13.8 KV level. Establishing the normal two bus configurations at Temple Place appeared to reduce the disturbance. These events suggested a controlled experiment to measure the magnet power swing and the induced powerline flicker; and from these measurements project the flicker on the lab site generated by the Booster operating at full energy. This experiment could corroborate the validity of the electrical models used in analyzing the power flow from the LILCO power grid and its distribution on the Lab site described in Accelerator Division Technical Note 220.

  7. Stimulus Overselectivity Four Decades Later: A Review of the Literature and Its Implications for Current Research in Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Ploog, Bertram O.

    2010-01-01

    This review of several topics related to "stimulus overselectivity" (Lovaas et al., J Abnormal Psychol 77:211-222, 1971) has three main purposes: (1) To outline the factors that may contribute to overselectivity; (2) to link the behavior-analytical notion of overselectivity to current nonbehavior-analytical research and theory; and (3) to suggest…

  8. Current-oscillator correlation and Fano factor spectrum of quantum shuttle with finite bias voltage and temperature.

    PubMed

    Lai, Wenxi; Cao, Yunshan; Ma, Zhongshui

    2012-05-01

    A general master equation is derived to describe an electromechanical single-dot transistor in the Coulomb blockade regime. In the equation, Fermi distribution functions in the two leads are taken into account, which allows one to study the system as a function of bias voltage and temperature of the leads. Furthermore, we treat the coherent interaction mechanism between electron tunneling events and the dynamics of excited vibrational modes. Stationary solutions of the equation are numerically calculated. We show that current through the oscillating island at low temperature appears to have step-like characteristics as a function of the bias voltage and the steps depend on the mean phonon number of the oscillator. At higher temperatures the current steps would disappear and this event is accompanied by the emergence of thermal noise of the charge transfer. When the system is mainly in the ground state, the zero frequency Fano factor of current manifests sub-Poissonian noise and when the system is partially driven into its excited states it exhibits super-Poissonian noise. The difference in the current noise would almost be removed for the situation in which the dissipation rate of the oscillator is much larger than the bare tunneling rates of electrons. PMID:22469613

  9. Current Status and Potential Impacts Regarding the Proposed Development of a Rail Line to the Yucca Mountain Nuclear Waste Repository

    SciTech Connect

    Lanthrum, G.; Gunnerson, J.

    2008-07-01

    This paper provides a description of the current status regarding the proposed development of a rail line to the Yucca Mountain Nuclear Waste Repository in Nye County, Southern Nevada, which includes potential impacts analyzed during the National Environmental Policy Act (NEPA) process, and the subsequent creation of an Environmental Impact Statement (EIS) for the rail line. Potential impacts are addressed within the context of impacts to natural and human environmental resources found within the geographic area of the proposed federal project. Potential impacts to these resources have been fully analyzed in the Rail Alignment Draft EIS (DEIS). This paper includes a summary of the potential impacts analyzed in the DEIS. Examples of potential impacts include land use conflicts, air quality, water use, and impacts to biological and cultural resources, among others. In conclusion: Based on its obligations under the NWPA and its decision to select the mostly rail scenario for the transportation of spent nuclear fuel and high-level radioactive waste, DOE needs to ship these materials by rail in Nevada to a repository at Yucca Mountain. DOE prepared the Rail Alignment EIS to provide the background, data, information, and analyses to help decision makers and the public understand the potential environmental impacts that could result from constructing and operating a railroad for shipment of spent nuclear fuel, high-level radioactive waste, and other materials from an existing rail line in Nevada to a repository at Yucca Mountain. This railroad would consist of a rail line, railroad operations support facilities, and other related infrastructure. DOE will use the Rail Alignment EIS to decide whether to construct and operate the proposed railroad, and if so, to: - Select a rail alignment (Caliente rail alignment or Mina rail alignment) in which to construct the railroad; - Select the common segments and alternative segments within either a Caliente rail alignment or a Mina

  10. Current status of extended spectrum β-lactamase-producing Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis in Okinawa prefecture, Japan.

    PubMed

    Nakama, Rika; Shingaki, Aoi; Miyazato, Hiroko; Higa, Rikako; Nagamoto, Chota; Hamamoto, Kouta; Ueda, Shuhei; Hachiman, Teruyuki; Touma, Yuki; Miyagi, Kazufumi; Kawahara, Ryuji; Toyosato, Takehiko; Hirai, Itaru

    2016-05-01

    Enterobacteriaceae producing extended spectrum β-lactamase (ESBL) are distributed worldwide. In this study, 114 ESBL-producing Enterobacteriaceae were isolated by analyzing 1672 clinical isolates of Enterobacteriaceae collected from an Okinawa prefectural hospital in Japan between June 2013 and July 2014. The overall prevalence of ESBL-producing Enterobacteriaceae was 6.8%; the prevalence of different bacterial species among the ESBL-producing isolates was as follows: 11.5% Escherichia coli (90 of 783 isolates), 6.2% Klebsiella pneumoniae (19 of 307 isolates), and 11.1% Proteus mirabilis (5 of 45 isolates). The ESBL types blaCTX-M-1, -3, -15, -2, -14, -27, and mutants of blaSHV-1 were detected. Among them, blaCTX-M-15 (33.3%), blaCTX-M-14 (27.8%) and blaCTX-M-27 (33.3%) were dominant in the E. coli isolates, whereas a blaSHV mutant which possessed four mutations (Tyr7Phe, Leu35Gln, Gly238Ser and Glu240Lys) in the amino acid sequence of SHV-1 dominated in the K. pneumoniae isolates (11 of 19, 57.9%). The pandemic E. coli ST131 clone was found to constitute 3.3% of the overall examined isolates and 62.2% of the ESBL-producing E. coli isolates. Our results suggest that the genetic combination of blaCTX-M, and blaSHV and antibiotics-resistant profile were different from that in other regions such as other areas of Japan, Asia, Europe, and North America, especially in the ESBL-producing K. pneumoniae isolates and in the E. coli B2-O25b-ST131 isolates possessing blaCTX-M-15 (40.7% of the E. coli B2-O25b-ST131 isolates). Taken together, our results indicate that the ESBL-producing Enterobacteriaceae in Okinawa, Japan, might be of a unique nature. PMID:26898665

  11. Evaluation of the Fourier Frequency Spectrum Peaks of Milk Electrical Conductivity Signals as Indexes to Monitor the Dairy Goats' Health Status by On-Line Sensors.

    PubMed

    Zaninelli, Mauro; Agazzi, Alessandro; Costa, Annamaria; Tangorra, Francesco Maria; Rossi, Luciana; Savoini, Giovanni

    2015-01-01

    The aim of this study is a further characterization of the electrical conductivity (EC) signal of goat milk, acquired on-line by EC sensors, to identify new indexes representative of the EC variations that can be observed during milking, when considering not healthy (NH) glands. Two foremilk gland samples from 42 Saanen goats, were collected for three consecutive weeks and for three different lactation stages (LS: 0-60 Days In Milking (DIM); 61-120 DIM; 121-180 DIM), for a total amount of 1512 samples. Bacteriological analyses and somatic cells counts (SCC) were used to define the health status of the glands. With negative bacteriological analyses and SCC < 1,000,000 cells/mL, glands were classified as healthy. When bacteriological analyses were positive or showed a SCC > 1,000,000 cells/mL, glands were classified as NH. For each milk EC signal, acquired on-line and for each gland considered, the Fourier frequency spectrum of the signal was calculated and three representative frequency peaks were identified. To evaluate data acquired a MIXED procedure was used considering the HS, LS and LS × HS as explanatory variables in the statistical model.Results showed that the studied frequency peaks had a significant relationship with the gland's health status. Results also explained how the milk EC signals' pattern change in case of NH glands. In fact, it is characterized by slower fluctuations (due to the lower frequencies of the peaks) and by an irregular trend (due to the higher amplitudes of all the main frequency peaks). Therefore, these frequency peaks could be used as new indexes to improve the performances of algorithms based on multivariate models which evaluate the health status of dairy goats through the use of gland milk EC sensors. PMID:26307993

  12. Evaluation of the Fourier Frequency Spectrum Peaks of Milk Electrical Conductivity Signals as Indexes to Monitor the Dairy Goats’ Health Status by On-Line Sensors

    PubMed Central

    Zaninelli, Mauro; Agazzi, Alessandro; Costa, Annamaria; Tangorra, Francesco Maria; Rossi, Luciana; Savoini, Giovanni

    2015-01-01

    The aim of this study is a further characterization of the electrical conductivity (EC) signal of goat milk, acquired on-line by EC sensors, to identify new indexes representative of the EC variations that can be observed during milking, when considering not healthy (NH) glands. Two foremilk gland samples from 42 Saanen goats, were collected for three consecutive weeks and for three different lactation stages (LS: 0–60 Days In Milking (DIM); 61–120 DIM; 121–180 DIM), for a total amount of 1512 samples. Bacteriological analyses and somatic cells counts (SCC) were used to define the health status of the glands. With negative bacteriological analyses and SCC < 1,000,000 cells/mL, glands were classified as healthy. When bacteriological analyses were positive or showed a SCC > 1,000,000 cells/mL, glands were classified as NH. For each milk EC signal, acquired on-line and for each gland considered, the Fourier frequency spectrum of the signal was calculated and three representative frequency peaks were identified. To evaluate data acquired a MIXED procedure was used considering the HS, LS and LS × HS as explanatory variables in the statistical model.Results showed that the studied frequency peaks had a significant relationship with the gland’s health status. Results also explained how the milk EC signals’ pattern change in case of NH glands. In fact, it is characterized by slower fluctuations (due to the lower frequencies of the peaks) and by an irregular trend (due to the higher amplitudes of all the main frequency peaks). Therefore, these frequency peaks could be used as new indexes to improve the performances of algorithms based on multivariate models which evaluate the health status of dairy goats through the use of gland milk EC sensors. PMID:26307993

  13. Inertial solvent dynamics and the analysis of spectral line shapes: Temperature-dependent absorption spectrum of beta-carotene in nonpolar solvent.

    PubMed

    Burt, Jim A; Zhao, Xihua; McHale, Jeanne L

    2004-03-01

    The influence of solvent dynamics on optical spectra is often described by a stochastic model which assumes exponential relaxation of the time-correlation function for solvent-induced frequency fluctuations. In contrast, theory and experiment suggest that the initial (subpicosecond) phase of solvent relaxation, resulting from inertial motion of the solvent, is a Gaussian function of time. In this work, we employ numerical and analytical calculations to compare the predicted absorption line shapes and the derived solvent reorganization energies obtained from exponential (Brownian oscillator) versus Gaussian (inertial) solvent dynamics. Both models predict motional narrowing as the ratio kappa = Lambda/Delta is increased, where Lambda and Delta are the frequency and variance, respectively, of the solvent-induced frequency fluctuations. However, the motional narrowing limit is achieved at lower values of kappa for the Brownian oscillator model compared to the inertial model. For a given line shape, the derived value of the solvent reorganization energy lambdasolv is only weakly dependent on the solvent relaxation model employed, though different solvent parameters Lambda and Delta are obtained. The two models are applied to the analysis of the temperature-dependent absorption spectrum of beta-carotene in isopentane and CS2. The derived values of lambdasolv using the Gaussian model are found to be in better agreement with the high temperature limit of Delta2/2kBT than are the values obtained using the Brownian oscillator model. In either approach, the solvent reorganization energy is found to increase slightly with temperature as a result of an increase in the variance Delta of the solvent-induced frequency fluctuations. PMID:15268604

  14. Inertial solvent dynamics and the analysis of spectral line shapes: Temperature-dependent absorption spectrum of β-carotene in nonpolar solvent

    NASA Astrophysics Data System (ADS)

    Burt, Jim A.; Zhao, Xihua; McHale, Jeanne L.

    2004-03-01

    The influence of solvent dynamics on optical spectra is often described by a stochastic model which assumes exponential relaxation of the time-correlation function for solvent-induced frequency fluctuations. In contrast, theory and experiment suggest that the initial (subpicosecond) phase of solvent relaxation, resulting from inertial motion of the solvent, is a Gaussian function of time. In this work, we employ numerical and analytical calculations to compare the predicted absorption line shapes and the derived solvent reorganization energies obtained from exponential (Brownian oscillator) versus Gaussian (inertial) solvent dynamics. Both models predict motional narrowing as the ratio κ=Λ/Δ is increased, where Λ and Δ are the frequency and variance, respectively, of the solvent-induced frequency fluctuations. However, the motional narrowing limit is achieved at lower values of κ for the Brownian oscillator model compared to the inertial model. For a given line shape, the derived value of the solvent reorganization energy λsolv is only weakly dependent on the solvent relaxation model employed, though different solvent parameters Λ and Δ are obtained. The two models are applied to the analysis of the temperature-dependent absorption spectrum of β-carotene in isopentane and CS2. The derived values of λsolv using the Gaussian model are found to be in better agreement with the high temperature limit of Δ2/2kBT than are the values obtained using the Brownian oscillator model. In either approach, the solvent reorganization energy is found to increase slightly with temperature as a result of an increase in the variance Δ of the solvent-induced frequency fluctuations.

  15. Measurement of the 1s2l3l’ Dielectronic Recombination Emission Line in Li-Like Ar and Its Contribution to the Faint X-Ray Feature Found in the Stacked Spectrum of Galaxy Clusters

    NASA Astrophysics Data System (ADS)

    Gall, Amy Christina; Silwal, Roshani; Dreiling, Joan; Borovik, Alexander; Ajello, Marco; Gillaspy, John; Kilgore, Ethan; Ralchenko, Yuri; Takacs, Endre

    2016-06-01

    Driven by the recent detection of an unidentified emission line previously reported at 3.55-3.57 keV in a stacked spectrum of galaxy clusters, we investigated the resonant DR process in Li-like Ar as a possible source of, or contributor to, the emission line. The Li-like transition 1s22l-1s2l3l’ was suggested to produce a 3.62 keV photon [1] near the unidentified line at 3.57 keV and was the primary focus of our investigation. Apart from the mentioned transitions, we have found other features that can be possible contributors to the emission in this region. The Electron Beam Ion Trap at NIST was used to produce and trap the highly-charged ions of argon. The energy of the quasi-monoenergetic electron beam was incremented in steps of 15 eV to scan over all of the Li-like Ar DR resonances. A Johann-type crystal spectrometer and a solid-state germanium detector were used to take x-ray measurements perpendicular to the electron beam. The DR cross sections were measured and normalized to the well-known photoionization cross sections using radiative recombination peaks in the measured spectra. Corrections for different instrument and method related effects such as charge state balance, electron beam space charge, and charge exchange have been considered. Our high-resolution crystal spectra allowed the experimental separation of features that are less than 2 eV apart. We have used a collisional radiative model NOMAD [2] aided by atomic data calculations by FAC [3] to interpret our observations and account for the corrections and uncertainties. Experimental results were compared to the AtomDB theoretical emission lines used to fit the galaxy cluster spectra containing the unidentified 3.57 keV line. These data points can be added benchmarks in the database and used to accurately interpret spectra from current x-ray satellites, including Hitomi, Chandra, and XMM-Newton x-ray observatories.[1] Bulbul E. et al., 2014, ApJ, 789, 13[2] Ralchenko Yu. et al., 2014, JQSRT, 71

  16. High I on/I off current ratio graphene field effect transistor: the role of line defect

    PubMed Central

    Tajarrod, Mohammad Hadi

    2015-01-01

    Summary The present paper casts light upon the performance of an armchair graphene nanoribbon (AGNR) field effect transistor in the presence of one-dimensional topological defects. The defects containing 5–8–5 sp2-hybridized carbon rings were placed in a perfect graphene sheet. The atomic scale behavior of the transistor was investigated in the non-equilibrium Green's function (NEGF) and tight-binding Hamiltonian frameworks. AGNRFET basic terms such as the on/off current, transconductance and subthreshold swing were investigated along with the extended line defect (ELD). The results indicated that the presence of ELDs had a significant effect on the parameters of the GNRFET. Compared to conventional transistors, the increase of the I on/I off ratio in graphene transistors with ELDs enhances their applicability in digital devices. PMID:26665077

  17. Current trends in the application of non-ceramic insulators for transmission & distribution lines subject to contamination

    SciTech Connect

    Riordan, K.C.

    1994-12-31

    Non-Ceramic Insulators (NCI) have been in application for more than 25 years. During this time, manufacturers have worked diligently to improve product designs and polymer materials. Today, the use of Non-Ceramic Polymer insulators is proliferating as Utilities become more confident in this advanced technology. The application advantages of NCI technology are more widely recognized and understood and credibility is growing in the long term service performance of these insulators. Current estimates place the NCI market share as high as 50% of the total US transmission insulator market. Indeed, Reliable Power Products is proud to advise that their insulators have been selected for the first 500 KV-DC transmission line in the USA to use 100% composite polymer insulators. With the combination of Los Angeles Department of Water and Power (Los Angeles to Las Vegas) and Salt River Project (Las Vegas to Phoenix), a total of almost 1,000 Kms. of transmission line will be insulated with Silicone Rubber Polymer Insulators. The total project will include almost 15,000 insulator strings. User confidence is not confined to the USA market. The application of NCI`s by International Utilities has also experienced significant growth. This may be evidenced by EHV installations in South America, Middle East, South Africa, Australia and South East Asia.

  18. On-line measurements of proton beam current from a PET cyclotron using a thin aluminum foil

    NASA Astrophysics Data System (ADS)

    Ghithan, S.; do Carmo, S. J. C.; Ferreira Marques, R.; Fraga, F. A. F.; Simões, H.; Alves, F.; Crespo, P.

    2013-07-01

    The number of cyclotrons capable of accelerating protons to about 20 MeV is increasing throughout the world. Originally aiming at the production of positron emission tomography (PET) radionuclides, some of these facilities are equipped with several beam lines suitable for scientific research. Radiobiology, radiophysiology, and other dosimetric studies can be performed using these beam lines. In this work, we measured the Bragg peak of the protons from a PET cyclotron using a stacked target consisting of several aluminum foils interleaved with polyethylene sheets, readout by in-house made transimpedance electronics. The measured Bragg peak is consistent with simulations performed using the SRIM/TRIM simulation toolkit. Furthermore, we report on experimental results aiming at measuring proton beam currents down to 10 pA using a thin aluminum foil (20-μm-thick). The aluminum was chosen for this task because it is radiation hard, it has low density and low radiation activity, and finally because it is easily available at negligible cost. This method allows for calculating the dose delivered to a target during an irradiation with high efficiency, and with minimal proton energy loss and scattering.

  19. Relationship between the spectral line based weighted-sum-of-gray-gases model and the full spectrum k-distribution model

    NASA Astrophysics Data System (ADS)

    Chu, Huaqiang; Liu, Fengshan; Consalvi, Jean-Louis

    2014-08-01

    The relationship between the spectral line based weighted-sum-of-gray-gases (SLW) model and the full-spectrum k-distribution (FSK) model in isothermal and homogeneous media is investigated in this paper. The SLW transfer equation can be derived from the FSK transfer equation expressed in the k-distribution function without approximation. It confirms that the SLW model is equivalent to the FSK model in the k-distribution function form. The numerical implementation of the SLW relies on a somewhat arbitrary discretization of the absorption cross section whereas the FSK model finds the spectrally integrated intensity by integration over the smoothly varying cumulative-k distribution function using a Gaussian quadrature scheme. The latter is therefore in general more efficient as a fewer number of gray gases is required to achieve a prescribed accuracy. Sample numerical calculations were conducted to demonstrate the different efficiency of these two methods. The FSK model is found more accurate than the SLW model in radiation transfer in H2O; however, the SLW model is more accurate in media containing CO2 as the only radiating gas due to its explicit treatment of ‘clear gas.’

  20. Current approaches to treatments for schizophrenia spectrum disorders, part II: psychosocial interventions and patient-focused perspectives in psychiatric care

    PubMed Central

    Chien, Wai Tong; Leung, Sau Fong; Yeung, Frederick KK; Wong, Wai Kit

    2013-01-01

    exception of patient relapse, the longer-term (eg, >2 years) effects of these approaches on most psychosocial outcomes are not well-established among these patients. Despite the fact that patients’ perspectives on treatment and care have been increasingly concerned, not many studies have evaluated the effect of interventions on this perspective, and where they did, the findings were inconclusive. To conclude, current approaches to psychosocial interventions for schizophrenia have their strengths and weaknesses, particularly indicating limited evidence on long-term effects. To improve the longer-term outcomes of people with schizophrenia, future treatment strategies should focus on risk identification, early intervention, person-focused therapy, partnership with family caregivers, and the integration of evidence-based psychosocial interventions into existing services. PMID:24109184

  1. [Spectrum diagnostic of arcjet].

    PubMed

    Zhao, Wen-Hua; Shen, Yan; Chen, Li-Ming

    2004-08-01

    Arcjet is a kind of propulsion device for mechanical operation and control of spacecraft. As its specific impulse is far greater than classical device using chemical propellant, arcjet is playing an increasing role in spacecraft propulsion. To improve our understanding of its working mechanics, the diagnostic method of arcjet is discussed and a set of spectrum diagnostic system is established in this paper. With this system, spectrum diagnostic was executed for Ar propellant at a setting value of flow rate and input current in a vacuum chamber. The result shows that the system has a high signal-to-noise ratio and the data collected can reflect the physical process objectively. Through transaction and analysis of these data, radial distribution of emission coefficient was obtained for different spectral lines, and radial distribution of temperature was also obtained through farther analysis of the emission coefficient. The result shows that under the experiment conditions of this paper, arcjet is in thermodynamic non-equilibrium state, therefore the temperatures obtained by different spectral lines are different. PMID:15766102

  2. The spatial evolution of t he directional wave spectrum in the Southern Ocean: Its relation to extreme waves in Agulhas Current

    NASA Technical Reports Server (NTRS)

    Beal, R. C.; Goldfinger, A.; Irvine, D.; Monaldo, F.; Tilley, D.; Shuchman, R.; Lyzenga, D.; Lyden, J.; Deleonibus, P.; Rufenach, C.

    1984-01-01

    An experiment using the Shuttle Imaging Radar-B (SIR-B) to monitor certain properties of the ocean wave directional spectrum and to track the long swell systems as they propagate northward to encounter the Agulhas near the southeastern coast of Africa is discussed. The experiment is designed around the unique capability of SIR-B to overcome key limitations of the Seasat synthetic aperture radar data set, and to extend the existing Seasat results into new areas. Ocean wave systems will be tracked. The variable-incidence-angle capability to examine wave imaging quality will be utilized. Doppler current measurements will be attempted. An effort will be made to verify that the lower range-to-velocity ratio of SIR-B will lead to the improved response of azimuth-traveling wave systems.

  3. Utility of the social communication questionnaire-current and social responsiveness scale as teacher-report screening tools for autism spectrum disorders.

    PubMed

    Schanding, G Thomas; Nowell, Kerri P; Goin-Kochel, Robin P

    2012-08-01

    Limited research exists regarding the role of teachers in screening for Autism Spectrum Disorders (ASD). The current study examined the use of the Social Communication Questionnaire (SCQ) and Social Responsiveness Scale (SRS) as completed by parents and teachers about school-age children from the Simons Simplex Collection. Using the recommended cutoff scores in the manuals and extant literature, the teacher-completed SCQ and SRS yielded lower sensitivity and specificity values than would be desirable; however, lowering the cutoff scores on both instruments improved sensitivity and specificity to more adequate levels for screening purposes. Using the adjusted cutoff scores, the SRS teacher form appears to be a slightly better screener than the SCQ. Implications and limitations are discussed, as well as areas for future research. PMID:22143742

  4. The application of new methane line absorption data to Gemini-N/NIFS and KPNO/FTS observations of Uranus' near-infrared spectrum

    NASA Astrophysics Data System (ADS)

    Irwin, P. G. J.; de Bergh, C.; Courtin, R.; Bézard, B.; Teanby, N. A.; Davis, G. R.; Fletcher, L. N.; Orton, G. S.; Calcutt, S. B.; Tice, D.; Hurley, J.

    2012-08-01

    New line data describing the absorption of CH4 and CH3D from 1.26 to 1.71 μm (Campargue, A., Wang, L., Mondelain, D., Kassi, S., Bézard, B., Lellouch, E., Coustenis, A., de Bergh, C., Hirtzig, M., Drossart, P. [2012]. Icarus 219, 110-128), building upon previous papers by Campargue et al. (Campargue, A., Wang, L., Kassi, S., Masat, M., Votava, O. [2010]. J. Quant. Spectrosc. Radiat. Transfer 111, 1141-1151; Wang, L., Kassi, S., Campargue, A. [2010]. J. Quant. Spectrosc. Radiat. Transfer 111, 1130-1140; Wang, L., Kassi, S., Liu, A.W., Hu, S.M., Campargue, A. [2011]. J. Quant. Spectrosc. Radiat. Transfer 112, 937-951)) have been applied to the analysis of Gemini-N/NIFS observations of Uranus made in 2010 and compared with earlier disc-averaged observations made by KPNO/FTS in 1982. The new line data are found to improve greatly the fit to the observed spectra and present a huge advance over previous methane absorption tables by allowing us to determine the CH3D/CH4 ratio and also start to break the degeneracy between methane abundance and cloud top height. The best fits are obtained if the cloud particles in the main cloud deck at the 2-3 bar level become less scattering with wavelength across the 1.4-1.6 μm region and we have modelled this variation here by varying the extinction cross-section and single-scattering albedo of the particles. Applying the new line data to the NIFS spectra of Uranus, we determine a new estimate of the CH3D/CH4 ratio of 2.9-0.5+0.9×10-4, which is consistent with the estimate of de Bergh et al. (de Bergh, C., Lutz, B.L., Owen, T., Brault, J., Chauville, J. [1986]. Astrophys. J. 311, 501-510) of 3.6-2.8+3.6×10-4, made by fitting a disc-averaged KPNO/FTS spectrum measured in 1982, but much better constrained. The NIFS observations made in 2010 have been disc-averaged and compared with the 1982 KPNO/FTS spectrum and found to be in excellent agreement. Using k-tables fitted to the new line data, the central meridian observations of

  5. Physical processes in an electron current layer causing intense plasma heating and formation of x-lines

    SciTech Connect

    Singh, Nagendra; Wells, B. E.; Khazanov, Igor

    2015-05-15

    We study the evolution of an electron current layer (ECL) through its several stages by means of three-dimensional particle-in-cell (PIC) simulations with ion to electron mass ratio M/m{sub e} = 400. An ECL evolves through the following stages: (i) Electrostatic (ES) current-driven instability (CDI) soon after its formation with half width w about 2 electron skin depth (d{sub e}), (ii) current disruption in the central part of the ECL by trapping of electrons and generation of anomalous resistivity, (iii) electron tearing instability (ETI) with significantly large growth rates in the lower end of the whistler frequency range, (iv) widening of the ECL and modulation of its width by the ETI, (v) gradual heating of electrons by the CDI-driven ES ion modes create the condition that the electrons become hotter than the ions, (vi) despite the reduced electron drift associated with the current disruption by the CDI, the enhanced electron temperature continues to favor a slow growth of the ion waves reaching nonlinear amplitudes, (vii) the nonlinear ion waves undergo modulation and collapse into localized density cavities containing spiky electric fields like in double layers (DLs), (viii) such spiky electric fields are very effective in further rapid heating of both electrons and ions. As predicted by the electron magnetohydrodynamic (EMHD) theories, the ETI growth rate maximizes at wave numbers in the range 0.4 < k{sub x}W < 0.8 where k{sub x} is the wave number parallel to the ECL magnetic field and w is the evolving half width of the ECL. The developing ETI generates in-plane currents that support out-of-plane magnetic fields around the emerging x-lines. The ETI and the spiky electrostatic structures are accompanied by fluctuations in the magnetic fields near and above the lower-hybrid (ion plasma) frequency, including the whistler frequency range. We compare our results with experimental results and satellite observation.

  6. Measuring the spectrum of mutation induced by nitrogen ions and protons in the human-hamster hybrid cell line A(L)C

    NASA Technical Reports Server (NTRS)

    Kraemer, S. M.; Kronenberg, A.; Ueno, A.; Waldren, C. A.; Chatterjee, A. (Principal Investigator)

    2000-01-01

    Astronauts can be exposed to charged particles, including protons, alpha particles and heavier ions, during space flights. Therefore, studying the biological effectiveness of these sparsely and densely ionizing radiations is important to understanding the potential health effects for astronauts. We evaluated the mutagenic effectiveness of sparsely ionizing 55 MeV protons and densely ionizing 32 MeV/nucleon nitrogen ions using cells of two human-hamster cell lines, A(L) and A(L)C. We have previously characterized a spectrum of mutations, including megabase deletions, in human chromosome 11, the sole human chromosome in the human-hamster hybrid cell lines A(L)C and A(L). CD59(-) mutants have lost expression of a human cell surface antigen encoded by the CD59 gene located at 11p13. Deletion of genes located on the tip of the short arm of 11 (11p15.5) is lethal to the A(L) hybrid, so that CD59 mutants that lose the entire chromosome 11 die and escape detection. In contrast, deletion of the 11p15.5 region is not lethal in the hybrid A(L)C, allowing for the detection of chromosome loss or other chromosomal mutations involving 11p15.5. The 55 MeV protons and 32 MeV/nucleon nitrogen ions were each about 10 times more mutagenic per unit dose at the CD59 locus in A(L)C cells than in A(L) cells. In the case of nitrogen ions, the mutations observed in A(L)C cells were predominantly due to chromosome loss events or 11p deletions, often containing a breakpoint in the pericentromeric region. The increase in the CD59(-) mutant fraction for A(L)C cells exposed to protons was associated with either translocation of portions of 11q onto a hamster chromosome, or discontinuous or "skipping" mutations. We demonstrate here that A(L)C cells are a powerful tool that will aid in the understanding of the mutagenic effects of different types of ionizing radiation.

  7. Discriminating autism spectrum disorders from schizophrenia by investigation of mental state attribution on an on-line mentalizing task: A review and meta-analysis.

    PubMed

    Bliksted, Vibeke; Ubukata, Shiho; Koelkebeck, Katja

    2016-03-01

    In recent years, theories of how humans form a "theory of mind" of others ("mentalizing") have increasingly been called upon to explain impairments in social interaction in mental disorders, such as autism spectrum disorders (ASD) and schizophrenia. However, it remains unclear whether tasks that assess impairments in mentalizing can also contribute to determining differential deficits across disorders, which may be important for early identification and treatment. Paradigms that challenge mentalizing abilities in an on-line, real-life fashion have been considered helpful in detecting disease-specific deficits. In this review, we are therefore summarizing results of studies that assess the attribution of mental states using an animated triangles task. Behavioral as well as brain imaging studies in ASD and schizophrenia have been taken into account. While for neuroimaging methods, data are sparse and investigation methods inconsistent, we performed a meta-analysis of behavioral data to directly investigate performance deficits across disorders. Here, more impaired abilities in the appropriate description of interactions were found in ASD patients than in patients with schizophrenia. Moreover, an analysis of first-episode (FES) versus longer lasting (LLS) schizophrenia showed that usage of mental state terms was reduced in the LLS group. In our review and meta-analysis, we identified performance differences between ASD and schizophrenia that seem helpful in targeting differential deficits, taking into account different stages of schizophrenia. However, to tackle the deficits in more detail, studies are needed that directly compare patients with ASD and schizophrenia using behavioral or neuroimaging methods with more standardized task versions. PMID:26817402

  8. Infrared spectrum involving forbidden transitions & coriolis interaction and identification of optically pumped far infrared laser lines in asymmetrically mono-deuterated methanol (Methanol-D1)

    NASA Astrophysics Data System (ADS)

    Mukhopadhyay, Indra

    2016-05-01

    In this paper new type of ΔK = 2 and 0 transitions have been identified in the Fourier Transform spectrum of Methanol-D1 (CH2DOH). These transitions are normally forbidden but a "Coriolis" type interaction with nearby states is believed to be contributing sufficient transition strength through intensity borrowing effect. This is the first time such forbidden transitions are reported to be identified in the excited states, in this molecule. The present conjecture is supported by observation of a many strong allowed transitions to upper terminating levels which are seen to be highly perturbed. This conclusion has been reached by comparing calculated energy levels using known molecular parameters (Pearson et al., 2012; Coudert et al., 2014; El Hilali et al., 2011; Quade et al., 1998; Richard Quade, 1998, 1999; Mukhopadhyay, 1997) and the actually observed FIR lines. The upper levels are seen to be upshifted from expected position. A closer look at the calculated energy values seems to indicate a possible interaction between the above states and other proximate torsional-rotational states could occur. The possible candidates for the interacting level manifolds are narrowed down through the presence of the forbidden transition. We also take the opportunity to propose alternate rotational quantum numbers for some of the assignments recently reported in the literature (El Hilali et al., 2011). Some ambiguities are pointed out on the data and the reported analysis. There remain too many such irregularities and we propose to gather a large body assigned transitions in a future catalog. Assignments and relevant comments on optically pumped FIR laser radiation are also made.

  9. Distribution of leakage currents in the cylindrical and conical sections of the magnetically insulated transmission line of the Angara-5-1 facility in experiments with wire arrays

    NASA Astrophysics Data System (ADS)

    Grabovski, E. V.; Gribov, A. N.; Samokhin, A. A.; Shishlov, A. O.

    2016-08-01

    Current leakages in the magnetically insulated transmission lines (MITL) impose restrictions on the transmission of electromagnetic pulses to the load in high-power electrophysical facilities. The multimodule Angara-5-1 facility with an output electric power of up to 6 TW is considered. In this work, the experimental and calculated profiles of leakage currents in two sections of the line are compared when the eight-module facility is loaded by a wire array. The azimuthal distribution of the current in the cylindrical section of the MITL is also considered.

  10. Master equation theory applied to the redistribution of polarized radiation in the weak radiation field limit. IV. Application to the second solar spectrum of the Na i D1 and D2 lines

    NASA Astrophysics Data System (ADS)

    Bommier, Véronique

    2016-06-01

    Context. The spectrum of the linear polarization, which is formed by scattering and observed on the solar disk close to the limb, is very different from the intensity spectrum and thus able to provide new information, in particular about anisotropies in the solar surface plasma and magnetic fields. In addition, a large number of lines show far wing polarization structures assigned to partial redistribution (PRD), which we prefer to denote as Rayleigh/Raman scattering. The two-level or two-term atom approximation without any lower level polarization is insufficient for many lines. Aims: In the previous paper of this series, we presented our theory generalized to the multilevel and multiline atom and comprised of statistical equilibrium equations for the atomic density matrix elements and radiative transfer equation for the polarized radiation. The present paper is devoted to applying this theory to model the second solar spectrum of the Na i D1 and D2 lines. Methods: The solution method is iterative, of the lambda-iteration type. The usual acceleration techniques were considered or even applied, but we found these to be unsuccessful, in particular because of nonlinearity or large number of quantities determining the radiation at each depth. Results: The observed spectrum is qualitatively reproduced in line center, but the convergence is yet to be reached in the far wings and the observed spectrum is not totally reproduced there. Conclusions: We need to investigate noniterative resolution methods. The other limitation lies in the one-dimensional (1D) atmosphere model, which is unable to reproduce the intermittent matter structure formed of small loops or spicules in the chromosphere. This modeling is rough, but the computing time in the presence of hyperfine structure and PRD prevents us from envisaging a three-dimensional (3D) model at this instant.

  11. Direct electric current treatment modifies mitochondrial function and lipid body content in the A549 cancer cell line.

    PubMed

    Holandino, Carla; Teixeira, Cesar Augusto Antunes; de Oliveira, Felipe Alves Gomes; Barbosa, Gleyce Moreno; Siqueira, Camila Monteiro; Messeder, Douglas Jardim; de Aguiar, Fernanda Silva; da Veiga, Venicio Feo; Girard-Dias, Wendell; Miranda, Kildare; Galina, Antonio; Capella, Marcia Alves Marques; Morales, Marcelo Marcos

    2016-10-01

    Electrochemical therapy (EChT) entails treatment of solid tumors with direct electric current (DC). This work evaluated the specific effects of anodic flow generated by DC on biochemical and metabolic features of the A549 human lung cancer cell line. Apoptosis was evaluated on the basis of caspase-3 activity and mitochondrial transmembrane potential dissipation. Cell morphology was analyzed using transmission electron microscopy, and lipid droplets were studied through morphometric analysis and X-ray qualitative elemental microanalysis. High-resolution respirometry was used to assess mitochondrial respiratory parameters. Results indicated A549 viability decreased in a dose-dependent manner with a prominent drop between 18 and 24h after treatment (p<0.001), together with a two-fold increase in caspase-3 activity. AF-treatment induced a significantly increase (p<0.01) in the cell number with disrupted mitochondrial transmembrane potential. Furthermore, treated cells demonstrated important ultrastructural mitochondria damage and a three-fold increase in the cytoplasmic lipid bodies' number, quantified by morphometrical analyses. Conversely, 24h after treatment, the cells presented a two-fold increase of residual oxygen consumption, accounting for 45.3% of basal oxygen consumption. These results show remarkable alterations promoted by anodic flow on human lung cancer cells which are possibly involved with the antitumoral effects of EChT. PMID:27243447

  12. Separation of four flavonoids from Rhodiola rosea by on-line combination of sample preparation and counter-current chromatography.

    PubMed

    Ma, Chaoyang; Hu, Liming; Fu, Qianyun; Gu, Xiaohong; Tao, Guanjun; Wang, Hongxin

    2013-09-01

    Purification of four flavonoids from Rhodiola rosea was developed by on-line combination of sample preparation and counter-current chromatography (CCC). Flavonoid sample was prepared by dynamic ultrasonic-assisted and solid-phase extraction using ion liquids as extractant. The preparation conditions were optimized by D-optimal design as follows: 2mol/L of 1-ethyl-3-methylimidazolium bromide concentration, 360W of ultrasonic power, 1.5mL/min of flow rate, 35min of extraction time and 0.5mL (absorbent) per g (material) of absorbent amount. The prepared sample solution (20mL) was loaded and injected directly into CCC column for final separation. As a result, four flavonoids, herbacetin-3-O-β-d-glucopyranosyl-7-O-α-l-rhamnopyranoside 1 (40.1mg), kaempferol-3-O-β-d-glucopyranosyl-7-O-α-l-rhamn-opyranoside 2 (4.6mg), kaempferol 3-O-β-d-glucopyranoside-(2→1)-β-d-xylopyranoside 3 (20.2mg) and herbacetin-8-O-β-d-glucopyranoside 4 (22.5mg), were obtained from 20g of R. rosea material using ethyl acetate-n-butanol-H2O as solvent system at a ratio of 4:1:5 by CCC. Their structures were identified by ESI-MS/MS, NMR methods. Their purities determined by UPLC were 98.5%, 95.4%, 98.1% and 97.5%, respectively. Kaempferol-3-O-β-d-glucopyranosyl-7-O-α-l-rhamnopyranoside 2 and herbacetin-8-O-β-d-glucopyrano-side 4 were isolated for first time from R. rosea. The purification method was simple, efficient and evaded tedious sample preparation process. PMID:23890556

  13. The evaluation of surface recombination velocity from normal-collector geometry electron-beam-induced current line scans

    NASA Astrophysics Data System (ADS)

    Luke, Keung L.

    1994-02-01

    There are two well-known point source-based methods for the evaluation of the surface recombination velocity s from normal-collector geometry electron-beam-induced current (EBIC) line scans. The first was proposed by Jastrzebski, Lagowski, and Gatos [Appl. Phys. Lett. 27, 537 (1975)], the second was by Watanabe, Actor, and Gatos (WAG) [IEEE Trans. Electron Dev. ED-24, 1172 (1977)]. Scheer, Wilhelm, and Lewerenz [J. Appl. Phys. 66, 5412 (1989)] were unsuccessful in using the first method to extract s from their EBIC data. Hakimzadeh, Möller, and Bailey [J. Appl. Phys. 72, 2919 (1992)] applied the second method to evaluate s from their EBIC data without accounting for the mismatch between the theoretical requirement and the experimental condition relating to source size and electron penetration depth at which the WAG expression is to be evaluated. In this article these two methods are evaluated and their applicability to both point and extended-source data is examined quantitatively. Their limitations and shortcomings led us to suggest a way to extend the applicability of the WAG expression to include extended sources and to formulate two new Gaussian source-based methods to evaluate the surface recombination velocity. A number of computed curves are provided to facilitate the application of these proposed new methods to GaAs and other semiconductors with diffusion lengths in the range of 0.5-3.0 μm and (surface recombination velocity/diffusion coefficient) values in the range of 103-106 cm-1.

  14. 77 FR 61330 - Policies Regarding Mobile Spectrum Holdings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-09

    ...In this document, the Commission seeks comment on whether to retain or modify the current case-by-case analysis used to evaluate mobile spectrum holdings in the context of transactions and auctions, as well as whether to adopt bright-line limits advocated by some providers and public interest groups. In addition, the Commission seeks comment on updating the spectrum bands that should be......

  15. Pediatric provider's perspectives on the transition to adult health care for youth with autism spectrum disorder: current strategies and promising new directions.

    PubMed

    Kuhlthau, Karen A; Warfield, Marji E; Hurson, Jill; Delahaye, Jennifer; Crossman, Morgan K

    2015-04-01

    Few youth with autism spectrum disorder (ASD) nationally report receiving services to help them transition from the pediatric health care system to the adult health care system. For example, only one-fifth (21.1%) of youth with ASD receive any transition planning services. To better understand why the transition from pediatric to adult health care is so difficult, we interviewed pediatric health care providers with extensive experience serving youth with ASD. We gathered information about the strategies and interventions they use to transition their patients with ASD to an adult provider. Five interventions or strategies are currently being used. These include providing families with written medical summaries to give to adult providers, compiling lists of available adult providers or community resources, coordinating care and communication between individual pediatric and adult providers, making transition-specific appointments, and using checklists to track transition progress. Other interventions or strategies were identified as needed but not currently in practice, and these focused on education and training. For example, informational workshops were suggested to train families and youth about transition. Training adult providers and medical students was also seen as important. Several respondents additionally identified the need for a transition center where all services could be coordinated in one place. With large numbers of youth with ASD becoming young adults, it seems that pediatric practices might want to consider some of the activities described here. Some of these activities, such as family educational seminars and written medical summaries, are likely relatively easy for a practice to implement. PMID:24497626

  16. Review of the current role of targeted therapies as maintenance therapies in first and second line treatment of epithelial ovarian cancer; In the light of completed trials.

    PubMed

    Korkmaz, Taner; Seber, Selcuk; Basaran, Gul

    2016-02-01

    Late and recurrent stage ovarian cancer has a high mortality and low response rate to therapy beyond first line treatment. Although first line platinum/taxane based regimens have a satisfactory response rate eventually in most cases disease recurrence is common and second-line treatments are not curative. Delaying progression or recurrence is the main goal of current ongoing clinical studies by means of establishing an effective maintenance regimen with acceptable toxicity profile. Clearly, the persistence of dormant and drug-resistant cells after front-line treatments results in the inability to cure the disease. Over the past several years, the idea of prolongation of therapy for ovarian cancer has garnered clinical attention and academic debate. As a result of a greater understanding of the molecular pathways involved in carcinogenesis and tumor growth, a large number of potential therapeutic targets have been identified and drugs to block receptors, ligands or pathways are being developed. Currently, numerous clinical trials with targeted agents have just been completed or are ongoing involving patients achieving a complete or durable response after first-line and beyond the first line chemotherapy in order to evaluate the efficacy of different therapeutic approaches in terms of progression-free survival and overall survival. PMID:26603345

  17. XMM-Newton/Reflection Grating Spectrometer detection of the missing interstellar O VII Kα absorption line in the spectrum of Cyg X-2

    NASA Astrophysics Data System (ADS)

    Cabot, Samuel H. C.; Wang, Q. Daniel; Yao, Yangsen

    2013-05-01

    The hot interstellar medium is an important part of the Galactic ecosystem and can be effectively characterized through X-ray absorption line spectroscopy. However, in a study of the hot medium using the accreting neutron star X-ray binary, Cyg X-2, as a background light source, a mystery came about when the putatively strong O VII Kα line was not detected in Chandra grating observations, while other normally weaker lines such as O VII Kβ as well as O VI and O VIII Kα are clearly present. We have investigated the grating spectra of Cyg X-2 from 10 XMM-Newton observations, in search of the missing line. We detect it consistently in nine of these observations, but the line is absent in the remaining one observation or is inconsistent with the detection in others at a ˜4σ confidence level. This absence of the line resembles that seen in the Chandra observations. Similarly, the O VI Kα line is found to disappear occasionally, but not in concert with the variation of the O VII Kα line. All these variations are most likely due to the presence of changing O VII and O VI Kα emission lines of Cyg X-2, which are blurred together with the absorption ones in the X-ray spectra. A re-examination of the Chandra grating data indeed shows evidence for a narrow emission line slightly off the O VI Kα absorption line. We further show that narrow N V emission lines with varying centroids and fluxes are present in far-ultraviolet spectra from the Cosmic Origins Spectrograph aboard the Hubble Space Telescope. These results provide new constraints on the accretion around the neutron star and on the X-ray-heating of the stellar companion. The understanding of these physical processes is also important to the fidelity of using such local X-ray binaries for interstellar absorption line spectroscopy.

  18. The Infrared Spectrum of Uranium Hollow Cathode Lamps from 850 nm to 4000 nm: Wavenumbers and Line Identifications from Fourier Transform Spectra

    NASA Astrophysics Data System (ADS)

    Redman, Stephen L.; Lawler, James E.; Nave, Gillian; Ramsey, Lawrence W.; Mahadevan, Suvrath

    2011-08-01

    We provide new measurements of wavenumbers and line identifications of 10, 100 U I and U II near-infrared (NIR) emission lines between 2500 cm-1 and 12, 000 cm-1 (4000-850 nm) using archival Fourier transform spectrometer spectra from the National Solar Observatory. This line list includes isolated uranium lines in the Y, J, H, K, and L bands (0.9-1.1 μm, 1.2-1.35 μm, 1.5-1.65 μm, 2.0-2.4 μm, and 3.0-4.0 μm, respectively), and provides six times as many calibration lines as thorium in the NIR spectral range. The line lists we provide enable inexpensive, commercially available uranium hollow cathode lamps to be used for high-precision wavelength calibration of existing and future high-resolution NIR spectrographs.

  19. THE INFRARED SPECTRUM OF URANIUM HOLLOW CATHODE LAMPS FROM 850 nm to 4000 nm: WAVENUMBERS AND LINE IDENTIFICATIONS FROM FOURIER TRANSFORM SPECTRA

    SciTech Connect

    Redman, Stephen L.; Ramsey, Lawrence W.; Mahadevan, Suvrath; Lawler, James E.; Nave, Gillian

    2011-08-01

    We provide new measurements of wavenumbers and line identifications of 10, 100 U I and U II near-infrared (NIR) emission lines between 2500 cm{sup -1} and 12, 000 cm{sup -1} (4000-850 nm) using archival Fourier transform spectrometer spectra from the National Solar Observatory. This line list includes isolated uranium lines in the Y, J, H, K, and L bands (0.9-1.1 {mu}m, 1.2-1.35 {mu}m, 1.5-1.65 {mu}m, 2.0-2.4 {mu}m, and 3.0-4.0 {mu}m, respectively), and provides six times as many calibration lines as thorium in the NIR spectral range. The line lists we provide enable inexpensive, commercially available uranium hollow cathode lamps to be used for high-precision wavelength calibration of existing and future high-resolution NIR spectrographs.

  20. Fission Spectrum

    DOE R&D Accomplishments Database

    Bloch, F.; Staub, H.

    1943-08-18

    Measurements of the spectrum of the fission neutrons of 25 are described, in which the energy of the neutrons is determined from the ionization produced by individual hydrogen recoils. The slow neutrons producing fission are obtained by slowing down the fast neutrons from the Be-D reaction of the Stanford cyclotron. In order to distinguish between fission neutrons and the remaining fast cyclotron neutrons both the cyclotron current and the pusle amplifier are modulated. A hollow neutron container, in which slow neutrons have a lifetime of about 2 milliseconds, avoids the use of large distances. This method results in much higher intensities than the usual modulation arrangement. The results show a continuous distribution of neutrons with a rather wide maximum at about 0.8 MV falling off to half of its maximum value at 2.0 MV. The total number of netrons is determined by comparison with the number of fission fragments. The result seems to indicate that only about 30% of the neutrons have energies below .8 MV. Various tests are described which were performed in order to rule out modification of the spectrum by inelastic scattering. Decl. May 4, 1951

  1. Design of a high-current low-energy beam transport line for an intense D-T/D-D neutron generator

    NASA Astrophysics Data System (ADS)

    Lu, Xiaolong; Wang, Junrun; Zhang, Yu; Li, Jianyi; Xia, Li; Zhang, Jie; Ding, Yanyan; Jiang, Bing; Huang, Zhiwu; Ma, Zhanwen; Wei, Zheng; Qian, Xiangping; Xu, Dapeng; Lan, Changlin; Yao, Zeen

    2016-03-01

    An intense D-T/D-D neutron generator is currently being developed at the Lanzhou University. The Cockcroft-Walton accelerator, as a part of the neutron generator, will be used to accelerate and transport the high-current low-energy beam from the duoplasmatron ion source to the rotating target. The design of a high-current low-energy beam transport (LEBT) line and the dynamics simulations of the mixed beam were carried out using the TRACK code. The results illustrate that the designed beam line facilitates smooth transportation of a deuteron beam of 40 mA, and the number of undesired ions can be reduced effectively using two apertures.

  2. Energy Spectrum of La3Lu2Ga3O12:Cr3+ and Its Pressure-Induced R-Line-Shift Reversal

    NASA Astrophysics Data System (ADS)

    Ma, Dong-Ping; Chen, Ju-Rong

    2005-12-01

    By means of both the theory for pressure-induced shifts (PS) of energy spectra and the theory for shifts of energy spectra due to electron-phonon interaction (EPI), the normal-pressure energy spectra of α and β centers of Cr3+ ions for LLGG:Cr3+ and the PS's of R1 lines and U band of these centers have been calculated at 10 K, respectively. The total calculated results are in very good agreement with the experimental data. For LLGG:Cr3+, the pressure-induced low-high crystal-field transition and the reversal of R1-line PS take place. The pressure-dependent variation of Rmixel (2E-4T2) [mixing-degree of |t22(3T1)e4T2 rangle and |t23 2Erangle base-wavefunctions in the wavefunction of R1 state without EPI] plays a key role for the reversal of R1-line PS. The behavior of the pure electronic PS of R1 line is quite different from that of the PS of R1 line due to EPI. It is the combined effect of them that gives rise to the total PS of R1 line. The comparison between R1-line PS's of GSGG:Cr3+ and LLGG:Cr3+ has been made. It is found that a peak of R1-line PS appears at Rmixel (2E-4T2) ≈ 0.08.

  3. On the equivalent widths determination of some lines arising from thea5D term of neutral iron in the solar spectrum.

    NASA Astrophysics Data System (ADS)

    Gasanalizade, A. G.

    Using the absolute oscillator strengths for Fe I lines by the Oxford scale and the absolute curve of growth of iron for two atmospheric models the author determines the equivalent widths of 21 solar lines of Fe I arising from the term a5D.

  4. The Use of Video Prompting on the Acquisition, Maintenance, and Generalization of a Line Dance by Adolescents with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Gies, Maria Louise

    2012-01-01

    Educators are in need of appropriate interventions for teaching individuals with autism spectrum disorders (ASD). A widely used (Bellini & Akullian, 2007; Delano, 2007) and evidence-based (Horner et al., 2005) instructional intervention for individuals with ASD is video modeling. Video modeling involves the learner viewing a video…

  5. Current lineages of the epithelioma papulosum cyprini (EPC) cell line are contaminated with fathead minnow, Pimephales promelas, cells

    USGS Publications Warehouse

    Winton, J.; Batts, W.; deKinkelin, P.; LeBerre, M.; Bremont, M.; Fijan, N.

    2010-01-01

    Initially established from proliferative skin lesions of the common carp, Cyprinus carpio L., the epithelioma papulosum cyprini (EPC) cell line (Fijan, Sulimanovic, Bearzotti, Muzinic, Zwillenberg, Chilmonczyk, Vautherot & de Kinkelin 1983) has become one of the most widely used tools for research on fish viruses and the diagnosis of fish viral diseases.

  6. THE SPECTRUM OF Fe II

    SciTech Connect

    Nave, Gillian; Johansson, Sveneric

    2013-01-15

    The spectrum of singly ionized iron (Fe II) has been recorded using high-resolution Fourier transform (FT) and grating spectroscopy over the wavelength range 900 A to 5.5 {mu}m. The spectra were observed in high-current continuous and pulsed hollow cathode discharges using FT spectrometers at the Kitt Peak National Observatory, Tucson, AZ and Imperial College, London and with the 10.7 m Normal Incidence Spectrograph at the National Institute of Standards and Technology. Roughly 12,900 lines were classified using 1027 energy levels of Fe II that were optimized to measured wavenumbers. The wavenumber uncertainties of lines in the FT spectra range from 10{sup -4} cm{sup -1} for strong lines around 4 {mu}m to 0.05 cm{sup -1} for weaker lines around 1500 A. The wavelength uncertainty of lines in the grating spectra is 0.005 A. The ionization energy of (130,655.4 {+-} 0.4) cm{sup -1} was estimated from the 3d{sup 6}({sup 5}D)5g and 3d{sup 6}({sup 5}D)6h levels.

  7. Zellweger Spectrum

    MedlinePlus

    ... the Zellweger spectrum result from defects in the assembly of a cellular structure called the peroxisome, and ... Zellweger spectrum are caused by defects in the assembly of the peroxisome. There are at least 12 ...

  8. Method for On-line Estimation of Electrical Motor Parameter Variation and Current Sensor Offset for SPM Motor

    NASA Astrophysics Data System (ADS)

    Uenaka, Yutaro; Sazawa, Masaki; Ohishi, Kiyoshi; Kenji, Takahashi

    The servo system of a permanent magnet (PM) motor should always maintain fine torque and fine speed responses. Accurate motor parameter identification is necessary for the PM motor servo system because the current control system is designed by considering the electric parameters of the PM motor. However, the motor parameters vary with the age of the motor and temperature. Moreover, current sensors have offset values. When the current sensor has offset values, the PM motor servo system produces torque ripple. In order to overcome these problems, this paper proposes a new real-time estimation method for both current sensor offsets and electrical parameters (resistance Ra, inductance La, and magnetic flux φfa) of the surface permanent magnet (SPM) motor. The proposed method involves the use of a real-time algorithm and a current simulator, which is operated using a DSP software system. In order to accurately estimate the motor parametera, the proposed method is using estimate currents, DC terms of sensor currents, and nominal motor parameter value. The experimental results of this study confirm that the proposed method satisfactorily estimates the current sensor offset of the U phase and V phase, as well as the electrical motor parametersRa, La, and φfa accurately.

  9. The Role of Velocity Redistribution in Enhancing the Intensity of the He II 304 A Line in the Quiet Sun Spectrum

    NASA Technical Reports Server (NTRS)

    Andretta, Vincenzo; Jordan, Stuart D.; Brosius, Jeffrey W.; Davila, Joseph M.; Thomas, Roger J.; Behring, William E.; Thompson, William T.; Garcia, Adriana

    1999-01-01

    We present observational evidence of the effect of small scale ("microturbulent") velocities in enhancing the intensity of the He II lambda304 line with respect to other transition region emission lines, a process we call "velocity redistribution". We first show results from the 1991 and 1993 flights of SERTS (Solar EUV Rocket Telescope and Spectrograph). The spectral resolution of the SERTS instrument was sufficient to infer that, at the spatial resolution of 5", the line profile is nearly gaussian both in the quiet Sun and in active regions. We were then able to determine, for the quiet Sun, a lower limit for the amplitude of non-thermal motions in the region of formation of the 304 A line of the order of 10 km/s. We estimated that, in the presence of the steep temperature gradients of the solar Transition Region (TR), velocities of this magnitude can significantly enhance the intensity of that line, thus at least helping to bridge the gap between calculated and observed values. We also estimated the functional dependence of such an enhancement on the relevant parameters (non-thermal velocities, temperature gradient, and pressure). We then present results from a coordinated campaign, using SOHO/CDS and H-alpha spectroheliograms from Coimbra Observatory, aimed at determining the relationship between regions of enhanced helium emission and chromospheric velocity fields and transition region emission in the quiescent atmosphere. Using these data, we examined the behavior of the He II lambda304 line in the quiet Sun supergranular network and compared it with other TR lines, in particular with O III lambda600. We also examined the association of 304 A emission with the so-called "coarse dark mottle", chromospheric structures seen in H-alpha red wing images and associated with spicules. We found that all these observations are consistent with the velocity redistribution picture.

  10. How the macroscopic current correlates with the microscopic flux-line distribution in a type-II superconductor: an experimental study

    NASA Astrophysics Data System (ADS)

    Hecher, Johannes; Zehetmayer, Martin; Weber, Harald W.

    2014-07-01

    We present a study of the real-space flux-line lattice (FLL) of pristine and neutron irradiated conventional type-II superconductors using scanning tunnelling microscopy. Our work is focused on the magnetic field range, where the critical current density shows a second peak as a result of neutron irradiation. Scanning tunnelling microscopy images, including more than 2000 flux lines, are used to evaluate various microscopic parameters describing the disorder of the FLL, such as the defect density, the nearest neighbour distances and correlation functions. These parameters are compared with the macroscopic critical current density of the samples. The results show a direct correlation of the micro- and macroscopic properties. We observe a clear transition from an ordered to a disordered lattice at the onset of the second peak. Moreover, we discuss the defects of the FLL and their accumulation to large clusters in the second peak region.

  11. Determination of energy release zones arising due to current losses in the convolution region of the magnetically insulated transmission lines of the ANGARA-5-1 facility

    SciTech Connect

    Grabovski, E. V.; Gribov, A. N.; Laukhin, Ya. N.; Shishlov, A. O.

    2015-05-15

    Among the factors limiting electromagnetic pulse transmission to the load in high-power electro-physical facilities, current losses in magnetically insulated transmission lines (MITLs) are of significant importance. One of such facilities is ANGARA-5-1—a multimodule facility with an output electric power of up to 6 TW. A fairly complicated configuration of the magnetic field in the convolution region of several MITLs makes it difficult to fix the places of current losses there. In this work, these places were determined by detecting the positions of IR sources in the convolution region of the MITLs of the ANGARA-5-1 facility.

  12. Emission spectrum of a sporadic fireball afterglow

    NASA Astrophysics Data System (ADS)

    Madiedo, J.; Trigo-Rodríguez, J.

    2014-07-01

    A mag. -11 fireball was imaged over southern Spain on April 14, 2013 at 22:35:49.8 ± 0.1s UTC. Its emission spectrum was also obtained. This event was assigned the SPMN code 140413 after the recording date. By the end of its atmospheric path, it exhibited a very bright flare which resulted in a persistent train whose spectrum was recorded. Here we present a preliminary analysis of this event and focus special attention on the evolution of the main emission lines in the spectrum of the afterglow. An array of low-lux CCD video devices (models 902H and 902H Ultimate from Watec Co.) operating from our stations at Sevilla and El Arenosillo was employed to record the SPMN140413 fireball. The operation of these systems is explained in [1,2]. Some of these are configured as spectrographs by attaching holographic diffraction gratings (1000 lines/mm) to the objective lens [3]. To calculate the atmospheric trajectory, radiant, and orbit we have employed our AMALTHEA software, which follows the planes intersection method [4]. The spectrum was analyzed with our CHIMET application [5]. The parent meteoroid impacted the atmosphere with an initial velocity of 28.9 ± 0.3 km/s and the fireball began at a height of 104.4 ± 0.5 km. The event ended at 80.7 ± 0.5 km above the ground level, with the main flare taking place at 83 ± 0.5 km. The calculated radiant and orbital parameters confirm the sporadic nature of the bolide. The calibrated emission spectrum shows that the most important contributions correspond to the Na I-1 (588.9 nm) and Mg I-2 (517.2 nm) multiplets. In the ultraviolet, the contribution from the H and K lines from Ca was also identified. As usual in meteor spectra, most of the lines correspond to Fe I. The train spectrum was recorded during about 0.12 seconds. This provided the evolution with time of the intensity of the emission lines in this signal. The contributions from Mg I, Na I, Ca I, Fe I, Ca II, and O I were identified in the afterglow, with the Na I-1

  13. Flux-lines lattice order and critical current studied by time-of-flight small-angle neutron scattering

    NASA Astrophysics Data System (ADS)

    Pautrat, Alain; Brulet, Annie; Simon, Charles; Mathieu, Patrice

    2012-05-01

    Small-angle neutron scattering is a historical technique to study the flux-lines lattice (FLL) in a superconductor. Structural characteristics of the FLL can be revealed, providing fundamental information for the physics of a vortex lattice. However, the spatial resolution is limited and all of the correlation lengths of order are difficult to extract with precision. We show here that a time-of-flight technique reveals the Bragg peak of the FLL, and also its translational order with a better resolution. We discuss the implication of these results for pinning mechanisms in a niobium sample.

  14. "Why Are We an Ignored Group?" Mainstream Educational Experiences and Current Life Satisfaction of Adults on the Autism Spectrum from an Online Survey

    ERIC Educational Resources Information Center

    Parsons, Sarah

    2015-01-01

    Adults on the autism spectrum are significantly under-represented in research on educational interventions and support, such that little is known about their views and experiences of schooling and how this prepared them for adult life. In addition, "good outcomes" in adult life are often judged according to normative assumptions and tend…

  15. "What Do You Like/Dislike about the Treatments You're Currently Using?": A Qualitative Study of Parents of Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Mackintosh, Virginia H.; Goin-Kochel, Robin P.; Myers, Barbara J.

    2012-01-01

    Children with autism spectrum disorders (ASD) often participate in many treatments, requiring parents' dedication of time, money, and energy, and necessitating dealing with multiple service providers. To learn about parents' experience in seeking and using treatments for their child with ASD, the authors asked them, "What do you like/dislike about…

  16. A Study of Current Interventions and Professional Development Interests of Teachers of Early Childhood Special Education for Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Balbo, Maria L.

    2010-01-01

    Although research-based interventions for young students with Autism Spectrum Disorders exist and are supported in the literature, early intervention teachers in public schools often lack knowledge and training in the adoption and proper use of these effective-intervention interventions. The purpose of this study was to investigate current…

  17. Pediatric Provider's Perspectives on the Transition to Adult Health Care for Youth with Autism Spectrum Disorder: Current Strategies and Promising New Directions

    ERIC Educational Resources Information Center

    Kuhlthau, Karen A.; Warfield, Marji E.; Hurson, Jill; Delahaye, Jennifer; Crossman, Morgan K.

    2015-01-01

    Few youth with autism spectrum disorder (ASD) nationally report receiving services to help them transition from the pediatric health care system to the adult health care system. For example, only one-fifth (21.1%) of youth with ASD receive any transition planning services. To better understand why the transition from pediatric to adult health care…

  18. The center-to-limb variation across the Fraunhofer lines of HD 189733. Sampling the stellar spectrum using a transiting planet

    NASA Astrophysics Data System (ADS)

    Czesla, S.; Klocová, T.; Khalafinejad, S.; Wolter, U.; Schmitt, J. H. M. M.

    2015-10-01

    The center-to-limb variation (CLV) describes the brightness of the stellar disk as a function of the limb angle. Across strong absorption lines, the CLV can vary quite significantly. We obtained a densely sampled time series of high-resolution transit spectra of the active planet host star HD 189733 with UVES. Using the passing planetary disk of the hot Jupiter HD 189733 b as a probe, we study the CLV in the wings of the Ca ii H and K and Na i D1 and D2 Fraunhofer lines, which are not strongly affected by activity-induced variability. In agreement with model predictions, our analysis shows that the wings of the studied Fraunhofer lines are limb brightened with respect to the (quasi-)continuum. The strength of the CLV-induced effect can be on the same order as signals found for hot Jupiter atmospheres. Therefore, a careful treatment of the wavelength dependence of the stellar CLV in strong absorption lines is highly relevant in the interpretation of planetary transit spectroscopy. Based on observations made with UVES at the ESO VLT Kueyen telescope under program 089.D-0701(A).

  19. A quantitative study of magnetospheric magnetic field line deformation by a two-loop substorm current wedge

    NASA Astrophysics Data System (ADS)

    Nikolaev, A. V.; Sergeev, V. A.; Tsyganenko, N. A.; Kubyshkina, M. V.; Opgenoorth, H.; Singer, H.; Angelopoulos, V.

    2015-04-01

    Substorm current wedge (SCW) formation is associated with global magnetic field reconfiguration during substorm expansion. We combine a two-loop model SCW (SCW2L) with a background magnetic field model to investigate distortion of the ionospheric footpoint pattern in response to changes of different SCW2L parameters. The SCW-related plasma sheet footprint shift results in formation of a pattern resembling an auroral bulge, the poleward expansion of which is controlled primarily by the total current in the region 1 sense current loop (I1). The magnitude of the footprint latitudinal shift may reach ∼ 10° corrected geomagnetic latitude (CGLat) during strong substorms (I1= 2 MA). A strong helical magnetic field around the field-aligned current generates a surge-like region with embedded spiral structures, associated with a westward traveling surge (WTS) at the western end of the SCW. The helical field may also contribute to rotation of the ionospheric projection of narrow plasma streams (auroral streamers). Other parameters, including the total current in the second (region 2 sense) loop, were found to be of secondary importance. Analyzing two consecutive dipolarizations on 17 March 2010, we used magnetic variation data obtained from a dense midlatitude ground network and several magnetospheric spacecraft, as well as the adaptive AM03 model, to specify SCW2L parameters, which allowed us to predict the magnitude of poleward auroral expansion. Auroral observations made during the two substorm activations demonstrate that the SCW2L combined with the AM03 model nicely describes the azimuthal progression and the observed magnitude of the auroral expansion. This finding indicates that the SCW-related distortions are responsible for much of the observed global development of bright auroras.

  20. Separation and purification of four compounds from Desmodium styracifolium using off-line two-dimensional high-speed counter-current chromatography.

    PubMed

    Su, Wen; Liu, Qi; Yang, Qing; Yu, Jingang; Chen, Xiaoqing

    2013-10-01

    An off-line 2D high-speed counter-current chromatography technique in preparative scale has been successfully applied to separate and purify the main compounds from the ethyl acetate extract of Desmodium styracifolium. A two-phase solvent system composed of n-hexane/ethyl acetate/methanol/water at an optimized volume ratio of 1:2:1:2 v/v/v/v was used. Conventional high-speed counter-current chromatography was used as the first dimension, and the upper phase of the solvent system was used as the stationary phase in the head-to-tail elution mode at a flow rate of 2.0 mL/min and a rotation speed of 900 rpm. Recycling high-speed counter-current chromatography served as the second dimension to separate an impure fraction of the first dimension. A total of four well-separated substances including vanillic acid (1), β-sitosterol (2), formononetin (3), and aromadendrin (4) were obtained, and their purities and structures were identified by HPLC-MS and (1) H NMR spectroscopy. The results illustrated that off-line 2D high-speed counter-current chromatography is an effective way to isolate compounds in complex samples. PMID:23939907

  1. Current approaches and challenges for chemical characterization of inhibitory effect against cancer cell line isolated from Gokshur extract.

    PubMed

    Bouabdallah, Salwa; Sghaier, Rabiaa-M; Selmi, Sawssen; Khlifi, Daycem; Laouini, Dhafer; Ben-Attia, Mossadok

    2016-07-15

    In the present study, the potential effect anti tumor and the chemical composition of different fractions of Gokshur was evaluated. Commonly known as puncture vine, it has been used for a long time in both the Indian and traditional Chinese medicine. It is popularly used as a remedy for fertility disorder in Ayurveda. Samples were collected during June-September 2014 in the Cap Bon (north east of the northern Tunisia). Different organs were separated and extracted by sequential process to compare and investigate their potential anti-tumor effect. For the first time, we report the antiproliferatif effect of leaves n-butannolic fraction against cancer cell lines. The better anti-tumor fraction (94.76±1.52%) has been detected and performed by RP-HPLC has shown a great peak area (5578.21Mau). Novel designed natural derivatives from Gokshur, a cyclotrisiloxane, major compound identified by GC-MS. PMID:26711680

  2. Comparison of the measured and calculated time profiles of the leakage current in the magnetically insulated transmission line of the angara-5-1 facility

    SciTech Connect

    Grabovski, E. V.; Gribov, A. N.; Samokhin, A. A.; Shishlov, A. O.

    2013-10-15

    One of the factors limiting the transmission of the electromagnetic pulse to the load in high-power electrophysical facilities is the current leakage in magnetically insulated transmission lines (MITLs). In this paper, the Angara-5-1 eight-module facility with an output power up to 6 TW is considered. The experimental and calculated time profiles of the leakage current for eight-module shots with a dynamic load (cylindrical arrays made of 40 tungsten wires) and single-module shots with a solid cylindrical metal load are compared. When interpreting the results, the contribution of vacuum electrons to the leakage current at the transition from the cylindrical to the conical section of the MITL is taken into account.

  3. Dynamical K Edge and Line Variations in the X-ray Spectrum of the Ultra-compact Binary 4U 0614+091

    NASA Astrophysics Data System (ADS)

    Schulz, N. S.; Nowak, M. A.; Chakrabarty, D.; Canizares, C. R.

    2010-12-01

    We observed the ultra-compact binary candidate 4U 0614+091 for a total of 200 ks with the high-energy transmission gratings on board the Chandra X-ray Observatory. The source is found at various intensity levels with spectral variations present. X-ray luminosities vary between 2.0 × 1036 erg s-1 and 3.5 × 1036 erg s-1. Continuum variations are present at all times and spectra can be fit well with a power-law component, a high kT blackbody component, and a broad line component near oxygen. The spectra require adjustments to the Ne K edge and in some occasions also to the Mg K edge. Once further resolved, the Ne K edge region appears variable in terms of optical depths and morphology. The edge vicinity reveals an average velocity smear of ~3500 km s-1 implying a characteristic radius of the order of <109 cm consistent with an ultra-compact binary nature. The variability proves that the excess is intrinsic to the source. The data seem to indicate excess column densities of up to several 1018 cm-2. However, there are some serious problems with an Ne I interpretation in ultra-compact disks and we need to consider alternative interpretations, which include a variable O VIII ionization edge, as likely candidates. We test such possibilities with existing observations. The prominent soft emission line complex near the O VIII Lyα position appears extremely broad and relativistic effects from near the innermost disk have to be included. Gravitationally broadened line fits also provide nearly edge-on angles of inclination consistent with the observed high dynamics near the Ne K edge. The emissions appear consistent with an ionized disk with ionization parameters of the order of 104 at radii of a few 107 cm. The line wavelengths with respect to O VIII Lyα are found variably blueshifted indicating more complex inner disk dynamics.

  4. Comparison between observed and theoretical O IV line ratios in the UV/EUV solar spectrum as derived by SUMER, CDS and EIS

    NASA Astrophysics Data System (ADS)

    Giunta, A. S.; Fludra, A.; O'Mullane, M. G.; Summers, H. P.

    2012-02-01

    Aims: The joint use of SoHO Solar Ultraviolet Measurement of Emitted Radiation (SUMER), Coronal Diagnostic Spectrometer (CDS) and Hinode Extreme-ultraviolet Imaging Spectrometer (EIS) allow observation of several O iv line ratios, useful for temperature plasma diagnostics. Accurate atomic data are required to avoid interpretation errors in deriving the electron temperature from these ratios. Muglach et al. (2010) found that the measured ratio I(787.72 Å)/I(279.93 Å) is lower than the predicted value by a factor 2-5. Here the predicted value for this ratio is revised using updated atomic data. A comparison with other observed O iv line ratios is shown and the electron temperature is derived. Methods: The analysis is based on new observations made during the observational campaign of April 2009 and including three O iv multiplets. The theoretical ratios have been derived using the Atomic Data and Analysis Structure (ADAS) database and include comparison with the most recent calculations available in the literature. Results: The discrepancy for the O iv I(787.72 Å)/I(279.93 Å) ratio has been solved by adding transitions involving higher excited levels, which have been omitted in previous atomic models. This results in a decrease of the theoretical line ratio, providing electron temperatures in the range of log T = 5.17-5.39, close to the temperature expected from a plasma in ionisation equilibrium.

  5. Separation of five flavonoids from tartary buckwheat (Fagopyrum tataricum (L.) Gaertn) grains via off-line two dimensional high-speed counter-current chromatography.

    PubMed

    Jiang, Shujing; Liu, Qi; Xie, Yixi; Zeng, Hualiang; Zhang, Li; Jiang, Xinyu; Chen, Xiaoqing

    2015-11-01

    An off-line two dimensional (2D) high-speed counter-current chromatography (HSCCC) strategy was successfully used for preparative separation of five flavonoids from tartary buckwheat (Fagopyrum tataricum (L.) Gaertn) grains with different solvent systems for the first time in this paper. n-Hexane-ethyl acetate-methanol-water 3:5:3:5 (v/v) was selected as the first dimension solvent system to purify quercetin (4) and kaempferol (5). The second dimension solvent system, ethyl acetate-n-butanol-water 7:3:10 (v/v), was used to isolate quercetin 3-O-rutinoside-3'-O-β-glucopyranoside (1), rutin (2) and kaempferol 3-rutinoside (3). The purities of these compounds were all above 96.0% and their structures were identified through UV, MS and (1)H NMR. The results indicated that the off-line 2D HSCCC is an efficient technique to isolate flavonoids compounds from grains. PMID:25976805

  6. Spectrum Recombination.

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    1984-01-01

    Describes several methods of executing lecture demonstrations involving the recombination of the spectrum. Groups the techniques into two general classes: bringing selected portions of the spectrum together using lenses or mirrors and blurring the colors by rapid movement or foreshortening. (JM)

  7. On the theory of critical currents and flux flow in superconductors by the mechanism of plastic deformation of the flux-line lattice

    SciTech Connect

    Welch, D.O.

    1999-07-01

    In this paper the author will discuss how the nature of the stress state in the flux-line lattice (FLL) of superconductors arises from the distribution, density, geometry, and strength of pinning centers. Under certain conditions this stress causes the onset of plastic deformation in the FLL for values of the current density below that required for flux-flow by general depinning. He will describe an analytic framework, based on a theory of plasticity of the FLL, which describes the flux-flow characteristics, including the possibility of thermally-activated flow and flux creep.

  8. ON THE THEORY OF CRITICAL CURRENTS AND FLUX FLOW IN SUPERCONDUCTORS BY THE MECHANISM OF PLASTIC DEFORMATION OF THE FLUX-LINE LATTICE.

    SciTech Connect

    WELCH,D.O.

    1999-07-07

    In this paper I will discuss how the nature of the stress state in the flux-line lattice (FLL) of superconductors arises from the distribution, density, geometry, and strength of pinning centers. Under certain conditions this stress causes the onset of plastic deformation in the FLL for values of the current density below that required for flux-flow by general depinning. I will describe an analytic framework, based on a theory of plasticity of the FLL, which describes the flux-flow characteristics, including the possibility of thermally-activated flow and flux creep.

  9. A Passive EMI Filter with Access to the Ungrounded Motor Neutral Line-Its Effect on Eliminating Leakage Current from the Inverter Heat Sink-

    NASA Astrophysics Data System (ADS)

    Doumoto, Takafumi; Akagi, Hirofumi

    This paper deals with a leakage current flowing out of the heat sink of a voltage-source PWM inverter. The heat-sink leakage current is caused by a steep change in the common-mode voltage produced by the inverter. It flows through parasitic capacitors between the heat sink and power semiconductor devices when no EMI filter is connected. Experimental results reveal that the heat-sink leakage current flows not into the supply side, but into the motor side. These understandings succeed in describing an equivalent common-mode circuit taking the parasitic capacitors into account. The authors have proposed a passive EMI filter that is unique in access to the ungrounded motor neutral line. It is discussed from this equivalent circuit that the passive EMI filter is effective in preventing the leakage current from flowing. Moreover, installation of another small-sized common-mode inductor at the ac side of the diode rectifier prevents the leakage current from flowing into the supply side. Experimental results obtained from a 200-V, 3.7-kW laboratory system confirm the effectiveness and viability of the EMI filter.

  10. Fast-Mixed Spectrum Reactor progress report. Results of the FMSR Benchmark calculations and an assessment of current fission product libraries

    SciTech Connect

    Ludewig, H.; Durston, C.; Atefi, B.; Cerbone, R.J.

    1980-06-01

    As part of the Initial Feasibility Study of the Fast Mixed Spectrum Reactor, a series of benchmark calculations were made to determine the sensitivity of the physics analysis to differences in methods and data. Argonne National Laboratory (ANL), the Massachusetts Institute of Technology (MIT), and Oak Ridge National Laboratory (ORNL) were invited to participate with Brookhaven National Laboratory in the analysis of a FMSR model prescribed by BNL. Detailed comparisons are made including a comprehensive study on the adequacy of the fission product treatments.

  11. Altered Actions of Memantine and NMDA-Induced Currents in a New Grid2-Deleted Mouse Line

    PubMed Central

    Kumagai, Ayako; Fujita, Akira; Yokoyama, Tomoki; Nonobe, Yuki; Hasaba, Yasuhiro; Sasaki, Tsutomu; Itoh, Yumi; Koura, Minako; Suzuki, Osamu; Adachi, Shigeki; Ryo, Haruko; Kohara, Arihiro; Tripathi, Lokesh P.; Sanosaka, Masato; Fukushima, Toshiki; Takahashi, Hiroyuki; Kitagawa, Kazuo; Nagaoka, Yasuo; Kawahara, Hidehisa; Mizuguchi, Kenji; Nomura, Taisei; Matsuda, Junichiro; Tabata, Toshihide; Takemori, Hiroshi

    2014-01-01

    Memantine is a non-competitive antagonist of the N-methyl-d-aspartate (NMDA) receptor, and is an approved drug for the treatment of moderate-to-severe Alzheimer’s disease. We identified a mouse strain with a naturally occurring mutation and an ataxic phenotype that presents with severe leg cramps. To investigate the phenotypes of these mutant mice, we screened several phenotype-modulating drugs and found that memantine (10 mg/kg) disrupted the sense of balance in the mutants. Moreover, the mutant mice showed an attenuated optokinetic response (OKR) and impaired OKR learning, which was also observed in wild-type mice treated with memantine. Microsatellite analyses indicated that the Grid2 gene-deletion is responsible for these phenotypes. Patch-clamp analysis showed a relatively small change in NMDA-dependent current in cultured granule cells from Grid2 gene-deleted mice, suggesting that GRID2 is important for correct NMDA receptor function. In general, NMDA receptors are activated after the activation of non-NMDA receptors, such as AMPA receptors, and AMPA receptor dysregulation also occurs in Grid2 mutant mice. Indeed, the AMPA treatment enhanced memantine susceptibility in wild-type mice, which was indicated by balance sense and OKR impairments. The present study explores a new role for GRID2 and highlights the adverse effects of memantine in different genetic backgrounds. PMID:25513882

  12. The ultraviolet lines of carbon, nitrogen, and oxygen in the IUE spectrum of the field horizontal-branch A star HD 109995

    NASA Technical Reports Server (NTRS)

    Leckrone, David S.; Adelman, Saul J.

    1986-01-01

    Photospheric abundances of C, N and O of an evolved halo Population 2 star, the field horizontal-branch star HD 109995, based on observations of ultraviolet resonance or low excitation lines are presented. The logarithmic abundance ratio with respect to the Sun O/Fe = +1.5 is substantially higher than previously determined values for Pop. 2 red giants or RR Lyrae stars, but agrees well with a derived value from the OI infrared triplet. This may be direct evidence of Tinsley's (1979) scenario of localized sharply rising interstellar oxygen abundances immediately following bursts of massive star formation. Star HD 109995 may have formed from such highly oxygen-enriched material prior to its dilution by gas with the pre-burst composition. The ratio C/N = -1.3 may reflect the composition of material from which the star formed or CN processing within the star during its evolution.

  13. An investigation of the ammonia absorption line near 6450 A in the spectrum of Saturn. II - A quantitative analysis of observations

    NASA Astrophysics Data System (ADS)

    Avramchuk, V. V.; Karmeliuk, A. I.

    Results of investigation of the Saturn spectra published earlier are analyzed. The rotation temperature (Trot = 129±8K) has been determined from the comparison of the intensities of ammonia lines λλ6444.6 Å (J = 3, K = 1), 6445.6 Å (J = 3, K = 2) and 6452.6 Å (J = 2, K = 1) in terms of the homogeneous half-infinite atmosphere model. The pressure is equal to 1.7±0.1 atm at the level of the ammonia band λ6450 Å formation. The volume concentration of gaseous ammonia in the cloud layer of Saturn is (6.7±1.2)×1012cm-3. The ratio of the volume concentration of ammonia and methane is (0.76±0.13)×10-2.

  14. Recurrent patterns of DNA methylation in the ZNF154, CASP8, and VHL promoters across a wide spectrum of human solid epithelial tumors and cancer cell lines

    PubMed Central

    Sánchez-Vega, Francisco; Gotea, Valer; Petrykowska, Hanna M; Margolin, Gennady; Krivak, Thomas C; DeLoia, Julie A; Bell, Daphne W; Elnitski, Laura

    2013-01-01

    The study of aberrant DNA methylation in cancer holds the key to the discovery of novel biological markers for diagnostics and can help to delineate important mechanisms of disease. We have identified 12 loci that are differentially methylated in serous ovarian cancers and endometrioid ovarian and endometrial cancers with respect to normal control samples. The strongest signal showed hypermethylation in tumors at a CpG island within the ZNF154 promoter. We show that hypermethylation of this locus is recurrent across solid human epithelial tumor samples for 15 of 16 distinct cancer types from TCGA. Furthermore, ZNF154 hypermethylation is strikingly present across a diverse panel of ENCODE cell lines, but only in those derived from tumor cells. By extending our analysis from the Illumina 27K Infinium platform to the 450K platform, to sequencing of PCR amplicons from bisulfite treated DNA, we demonstrate that hypermethylation extends across the breadth of the ZNF154 CpG island. We have also identified recurrent hypomethylation in two genomic regions associated with CASP8 and VHL. These three genes exhibit significant negative correlation between methylation and gene expression across many cancer types, as well as patterns of DNaseI hypersensitivity and histone marks that reflect different chromatin accessibility in cancer vs. normal cell lines. Our findings emphasize hypermethylation of ZNF154 as a biological marker of relevance for tumor identification. Epigenetic modifications affecting the promoters of ZNF154, CASP8, and VHL are shared across a vast array of tumor types and may therefore be important for understanding the genomic landscape of cancer. PMID:24149212

  15. Measurements of Tc (Q,P): Depression of the Superfluid Transition Temperature by a Heat Current Along the Lambda Line

    NASA Technical Reports Server (NTRS)

    Liu, Yuan-Ming; Larson, Melora; Israelsson, Ulf

    1999-01-01

    We report experimental measurements of Tc (Q,P) for heat currents (Q) between I1and 100 micro W/sq cm and pressure (P) between SVP and 15 bar. The measurements were performed in a normal gravity environment, using the low-gravity simulator facility at JPL without the magnet being energized. The sample pressure was controlled to 0.1 micro bar using a hot volume, and a Straty-Adams capacitive pressure gauge. The total volume of helium in the sample cell and the hot volume was held constant using a pneumatic low temperature valve. A melting curve thermometer (MCT) measured the transition temperature (Tc) with a resolution of about 10 nK through a sidewall probe of the thermal conductivity sample cell. We employed the same measurement technique and procedure described by DAS. Preliminary results indicate that Tc (Q,P) depends very little on the pressure in the pressure range between SVP and 15 bar with a variation in the amplitude of Tc(Q,P) of less than about 5% observable in this pressure range. According to the Renormalization-group theory calculation by Haussmann and Dohm, the amplitude of Tc (Q,P) has a leading pressure-dependence term proportional to xi(sub 0) (sup (1/nu)), where xi(sub 0) is the correlation-length amplitude and nu is the correlation-length exponent. Thus, a small pressure dependence of the amplitude of Tc (Q,P) is expected since xi(sub 0) is very weakly dependent on pressure between SVP and 15 bar, consistent with our measurements.

  16. Transmission of HIV Drug Resistance and the Predicted Effect on Current First-line Regimens in Europe

    PubMed Central

    Hofstra, L. Marije; Sauvageot, Nicolas; Albert, Jan; Alexiev, Ivailo; Garcia, Federico; Struck, Daniel; Van de Vijver, David A. M. C.; Åsjö, Birgitta; Beshkov, Danail; Coughlan, Suzie; Descamps, Diane; Griskevicius, Algirdas; Hamouda, Osamah; Horban, Andrzej; Van Kasteren, Marjo; Kolupajeva, Tatjana; Kostrikis, Leondios G.; Liitsola, Kirsi; Linka, Marek; Mor, Orna; Nielsen, Claus; Otelea, Dan; Paraskevis, Dimitrios; Paredes, Roger; Poljak, Mario; Puchhammer-Stöckl, Elisabeth; Sönnerborg, Anders; Staneková, Danica; Stanojevic, Maja; Van Laethem, Kristel; Zazzi, Maurizio; Zidovec Lepej, Snjezana; Boucher, Charles A. B.; Schmit, Jean-Claude; Wensing, Annemarie M. J.

    2016-01-01

    Background. Numerous studies have shown that baseline drug resistance patterns may influence the outcome of antiretroviral therapy. Therefore, guidelines recommend drug resistance testing to guide the choice of initial regimen. In addition to optimizing individual patient management, these baseline resistance data enable transmitted drug resistance (TDR) to be surveyed for public health purposes. The SPREAD program systematically collects data to gain insight into TDR occurring in Europe since 2001. Methods. Demographic, clinical, and virological data from 4140 antiretroviral-naive human immunodeficiency virus (HIV)–infected individuals from 26 countries who were newly diagnosed between 2008 and 2010 were analyzed. Evidence of TDR was defined using the WHO list for surveillance of drug resistance mutations. Prevalence of TDR was assessed over time by comparing the results to SPREAD data from 2002 to 2007. Baseline susceptibility to antiretroviral drugs was predicted using the Stanford HIVdb program version 7.0. Results. The overall prevalence of TDR did not change significantly over time and was 8.3% (95% confidence interval, 7.2%–9.5%) in 2008–2010. The most frequent indicators of TDR were nucleoside reverse transcriptase inhibitor (NRTI) mutations (4.5%), followed by nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations (2.9%) and protease inhibitor mutations (2.0%). Baseline mutations were most predictive of reduced susceptibility to initial NNRTI-based regimens: 4.5% and 6.5% of patient isolates were predicted to have resistance to regimens containing efavirenz or rilpivirine, respectively, independent of current NRTI backbones. Conclusions. Although TDR was highest for NRTIs, the impact of baseline drug resistance patterns on susceptibility was largest for NNRTIs. The prevalence of TDR assessed by epidemiological surveys does not clearly indicate to what degree susceptibility to different drug classes is affected. PMID:26620652

  17. Angular on-line tube current modulation in multidetector CT examinations of children and adults: The influence of different scanning parameters on dose reduction

    SciTech Connect

    Papadakis, Antonios E.; Perisinakis, Kostas; Damilakis, John

    2007-07-15

    The purpose of this study was to assess the potential of angular on-line tube current modulation on dose reduction in pediatric and adult patients undergoing multidetector computed tomography (MDCT) examinations. Five physical anthropomorphic phantoms that simulate the average individual as neonate, 1-year-old, 5-year-old, 10-year-old, and adult were employed in the current study. Phantoms were scanned with the use of on-line tube current modulation (TCM). Percent dose reduction (%DR) factors achieved by applying TCM, were determined for standard protocols used for head and neck, shoulder, thorax, thorax and abdomen, abdomen, abdomen and pelvis, pelvis, and whole body examinations. A preliminary study on the application of TCM in MDCT examinations of adult patients was performed to validate the results obtained in anthropomorphic phantoms. Dose reduction was estimated as the percentage difference of the modulated milliamperes for each scan and the preset milliamperes prescribed by the scan protocol. The dose reduction in children was found to be much lower than the corresponding reduction achieved for adults. For helical scans the %DR factors, ranged between 1.6% and 7.4% for the neonate, 2.9% and 8.7% for the 1-year old, 2% and 6% for the 5-year-old, 5% and 10.9% for the 10-year-old, and 10.4% and 20.7% for the adult individual. For sequential scans the corresponding %DR factors ranged between 1.3% and 6.7%, 4.5% and 11%, 4.2% and 6.6%, 6.4% and 12.3%, and 8.9% and 23.3%, respectively. Broader beam collimations are associated with decreased %DR factors, when other scanning parameters are held constant. TCM did not impair image noise. In adult patients, the %DR values were found to be in good agreement with the corresponding results obtained in the anthropomorphic adult phantom. In conclusion, on-line TCM may be considered as a valuable tool for reducing dose in routine CT examinations of pediatric and adult patients. However, the dose reduction achieved with TCM

  18. On-line coupling of counter-current chromatography and macroporous resin chromatography for continuous isolation of arctiin from the fruit of Arctium lappa L.

    PubMed

    Guo, Mengzhe; Liang, Junling; Wu, Shihua

    2010-08-13

    In this work, we have developed a novel hybrid two-dimensional counter-current chromatography and liquid chromatography (2D CCC x LC) system for the continuous purification of arctiin from crude extract of Arctium lappa. The first dimensional CCC column has been designed to fractionalize crude complex extract into pure arctiin effluent using a one-component organic/salt-containing system, and the second dimensional LC column has been packed with macroporous resin for on-line adsorption, desalination and desorption of arctiin which was effluent purified from the first CCC dimension. Thus, the crude arctiin mixture has been purified efficiently and conveniently by on-line CCC x LC in spite of the use of a salt-containing solvent system in CCC separation. As a result, high purity (more than 97%) of arctiin has been isolated by repeated injections both using the ethyl acetate-8% sodium chloride aqueous solution and butanol-1% sodium chloride aqueous solution. By contrast with the traditional CCC processes using multi-component organic/aqueous solvent systems, the present on-line CCC x LC process only used a one-component organic solvent and thus the solvent is easier to recover and regenerate. All of used solvents such as ethyl acetate, n-butanol and NaCl aqueous solution are low toxicity and environment-friendly. Moreover, the lower phase of salt-containing aqueous solution used as mobile phase, only contained minor organic solvent, which will save much organic solvent in continuous separation. In summary, our results indicated that the on-line hybrid 2D CCC x LC system using one-component organic/salt-containing aqueous solution is very promising and powerful tool for high-throughput purification of arctiin from fruits of A. lappa. PMID:20619844

  19. ELF magnetic fields tuned to ion parametric resonance conditions do not affect TEA-sensitive voltage-dependent outward K(+) currents in a human neural cell line.

    PubMed

    Gavoçi, Entelë; Zironi, Isabella; Remondini, Daniel; Virelli, Angela; Castellani, Gastone; Del Re, Brunella; Giorgi, Gianfranco; Aicardi, Giorgio; Bersani, Ferdinando

    2013-12-01

    Despite the experimental evidence of significant biological effects of extremely low frequency (ELF) magnetic fields (MFs), the underlying mechanisms are still unclear. Among the few mechanisms proposed, of particular interest is the so called "ion parametric resonance (IPR)" hypothesis, frequently referred to as theoretical support for medical applications. We studied the effect of different combinations of static (DC) and alternating (AC) ELF MFs tuned on resonance conditions for potassium (K(+)) on TEA-sensitive voltage-dependent outward K(+) currents in the human neuroblastoma BE(2)C cell line. Currents through the cell membrane were measured by whole-cell patch clamp before, during, and after exposure to MF. No significant changes in K(+) current density were found. This study does not confirm the IPR hypothesis at the level of TEA-sensitive voltage-dependent outward K(+) currents in our experimental conditions. However, this is not a direct disprove of the hypothesis, which should be investigated on other ion channels and at single channel levels also. PMID:23900932

  20. The Rotational Spectrum of CHF 3 in the Submillimeter-Wave and Far-Infrared Region: Observation of the K = 3 Line Splitting

    NASA Astrophysics Data System (ADS)

    Cazzoli, G.; Cludi, L.; Cotti, G.; Dore, L.; Esposti, C. D.; Bellini, M.; Denatale, P.

    1994-02-01

    The milimeter-wave, submillimeter-wave. and FIR spectra of the ground state of CHF 3 have been observed and analyzed up to J = 78. The resulting spectroscopic constants are: B0/MHz = 10 348.8706(2), D J/kHz= 11.34482(13), D JK/kHz = -18.11765(50), H JJJ/Hz= 0.020069(24), H JJK/Hz = -0.08598(10), H KKJ/Hz 0.11372(27), L J/mHz = -0.669(16) × 10 -4, L JJK/mHz = 0.4953(80) × 10 -3, L JK/mHz = -0.1189(17) × 10 -2, and L JKK/mHz = -0.1115(31) × 10 -2. The splitting of the K = 3 ground state lines has been observed starting from the J = 29 ← 28 transition and the determined values of the splitting constants are h3/Hz = 0.29689(45) ×10 -2 and δ h3/Hz = -0.2054(52) × 10 -7.

  1. Phosphine spectrum at 4-5 μm: Analysis and line-by-line simulation of 2ν2, ν2 + ν4, 2ν4, ν1, and ν3 bands

    NASA Astrophysics Data System (ADS)

    Tarrago, G.; Lacome, N.; Lévy, A.; Guelachvili, G.; Bézard, B.; Drossart, P.

    1992-07-01

    The five absorption bands of PH3 at 4-5 μm, i.e., 2ν2, ν2 + ν4, 2ν4, ν1, ν3, were simultaneously analyzed from FT spectra recorded with an apodized resolution of 0.0054 cm-1. A theoretical model suited to the strong vibro-rotational couplings among the five bands was used. More than 4400 transitions (J <= 16) pertaining to the five bands were assigned in the range 1885-2445 cm-1, but only 3766 relatively unblended transitions were finally retained for the adjustment of the upper state energy parameters. A set of 57 energy parameters was required to reproduce the experimental wavenumbers with an overall standard deviation of 0.009 cm-1, consistent with the estimated upper limit of uncertainty when taking into account all factors of experimental errors. Absolute intensities of about 1600 lines were also measured, mainly in 2ν2, ν2 + ν4, and 2ν4 bands. The fitting of these data was achieved by using a restricted set of 53 energy parameters which yields the best compromise for both spectral position and intensity analyses. An estimate was then obtained for the four dipole moment derivatives involved in 2ν2, ν2 + ν4, and 2ν4, allowing us to reproduce the intensity measurements with an overall standard deviation of 10.9%, consistent with the experimental uncertainties. Absolute bandstrengths relative to 2ν2, ν2 + ν4, and 2ν4 were thus derived for the first time. Last, a line-by-line simulation of the five bands (J <= 16) was carried out in a form suitable for planetary applications. PH3, which is observed in Jupiter and Saturn, is an important molecule for studies of their atmospheric structures. The 5-μm bands are of special importance because the atmospheres are sounded deep at these wavelengths. Laboratoire Associé aux Universités Paris-Sud et P. et M. Curie.

  2. Micro acoustic spectrum analyzer

    DOEpatents

    Schubert, W. Kent; Butler, Michael A.; Adkins, Douglas R.; Anderson, Larry F.

    2004-11-23

    A micro acoustic spectrum analyzer for determining the frequency components of a fluctuating sound signal comprises a microphone to pick up the fluctuating sound signal and produce an alternating current electrical signal; at least one microfabricated resonator, each resonator having a different resonant frequency, that vibrate in response to the alternating current electrical signal; and at least one detector to detect the vibration of the microfabricated resonators. The micro acoustic spectrum analyzer can further comprise a mixer to mix a reference signal with the alternating current electrical signal from the microphone to shift the frequency spectrum to a frequency range that is a better matched to the resonant frequencies of the microfabricated resonators. The micro acoustic spectrum analyzer can be designed specifically for portability, size, cost, accuracy, speed, power requirements, and use in a harsh environment. The micro acoustic spectrum analyzer is particularly suited for applications where size, accessibility, and power requirements are limited, such as the monitoring of industrial equipment and processes, detection of security intrusions, or evaluation of military threats.

  3. Blood lines conduct leakage current during haemodialysis: a potential safety risk during first failure, especially for patients with central dialysis catheter as access.

    PubMed

    Jonsson, P; Eliasson, G; Stegmayr, B G

    2005-11-01

    Haemodialysis (HD) machines are IEC-classified as I type B. When central dialysis catheters (CDCs) are used for access, there will be close electrical contact with the heart. To investigate the risk for HD patients, the leakage of current through the tubing set was measured during in vitro dialysis performed according to the IEC 60601-1 standard for class I cardiac floating (CF) devices. A series of eight measurements were made with Gambro GFS + 12 dialysers, first with saline and then with blood in the blood lines. The leakage current exceeded the CF limit (50 microA) at the top of the CDC using the test 'mains on applied part' for saline (median 1008 microA, range 720-1241 microA), for blood (median 610 microA, range 449-772 microA) and also for a 'single fault condition' using saline (median 68 microA, range 35-118 microA) or blood (47 microA, range 4-128 microA). In the single fault condition, the highest leakage current at the CDC (128 microA) almost exceeded the earth leakage current in normal conditions. A safety risk can appear if a single fault arises in the dialysis machine or another device connected to the same patient, or during 'mains contact to the patient'. Then the current flow may be high enough to induce arrhythmias in the patient, especially when a CDC is used. These data and the use of CDCs as access for dialysis indicate that HD machines should be classified as cardiac floating rather than body (B) devices. PMID:16594299

  4. Current Concepts in Antimicrobial Therapy Against Resistant Gram-Negative Organisms: Extended-Spectrum β-Lactamase–Producing Enterobacteriaceae, Carbapenem-Resistant Enterobacteriaceae, and Multidrug-Resistant Pseudomonas aeruginosa

    PubMed Central

    Kanj, Souha S.; Kanafani, Zeina A.

    2011-01-01

    The development of antimicrobial resistance among gram-negative pathogens has been progressive and relentless. Pathogens of particular concern include extended-spectrum β-lactamase–producing Enterobacteriaceae, carbapenem-resistant Enterobacteriaceae, and multidrug-resistant Pseudomonas aeruginosa. Classic agents used to treat these pathogens have become outdated. Of the few new drugs available, many have already become targets for bacterial mechanisms of resistance. This review describes the current approach to infections due to these resistant organisms and elaborates on the available treatment options. PMID:21364117

  5. Separation of polyphenols from leaves of Malus hupehensis (Pamp.) Rehder by off-line two-dimensional High Speed Counter-Current Chromatography combined with recycling elution mode.

    PubMed

    Liu, Qi; Zeng, Hualiang; Jiang, Shujing; Zhang, Li; Yang, Fuzhu; Chen, Xiaoqing; Yang, Hua

    2015-11-01

    In this study, off-line two-dimensional High Speed Counter-Current Chromatography (2D HSCCC) strategy combined with recycling elution mode was developed to isolate compounds from the ethyl acetate extract of a common green tea--leaves of Malus hupehensis (Pamp.) Rehder. In the orthogonal separation system, a conventional HSCCC was employed for the first dimension and two recycling HSCCCs were used for the second in parallel. Using a solvent system consisting of n-hexane-ethyl acetate-methanol-water (1:4:0.6:4.4, v/v) in the first and second dimension, four compounds including 3-hydroxy-phlorizin (1), phloretin (2), avicularin (3) and kaempferol 3-O-β-D-glucoside (4) were obtained. The purities of these four compounds were all over 95.0% as determined by HPLC. And their structures were all identified through UV, MS and (1)H NMR. It has been demonstrated that the combination of off-line 2D HSCCC with recycling elution mode is an efficient technique to isolate compounds with similar polarities in natural products. PMID:25976803

  6. Tokamak halo currents

    SciTech Connect

    Boozer, Allen H.

    2013-08-15

    A halo current flows for part of its path through the plasma edge and for part through the chamber walls and can be as large as tenths of the plasma current. The primary interest in halo currents is the large force that they can exert on machine components. Two discordant constraints are central to the theory: (1) Halo currents must produce the magnetic field distribution required to maintain plasma force balance—a distribution that depends on the two angular coordinates of a torus. (2) Halo currents must flow along the magnetic field lines in the plasma, which implies a dependence on a linear combination of the two angular coordinates—only one angular coordinate is free. The physics basis of these two constraints is explained as is their application to the calculation of the properties of halo currents, such as their broad toroidal spectrum. Existing codes could be used to (1) provide detailed comparisons with experiments to validate that the critical elements of physics are adequately included, (2) allow more complete predictions for future machines such as ITER, and (3) design shunts and resistive elements to ensure halo currents follow paths that are the least damaging to the machine. The physics of halo currents implies that it may be possible to feedback stabilize resistive wall modes beyond the ideal-wall limit.

  7. Cerebral palsy: A reconceptualization of the spectrum.

    PubMed

    Shapiro, Bruce K

    2004-08-01

    Approximately 50 years ago, interest in cerebral palsy increased, and the current definitions and classification were developed. The interplay among the dimensions of significant impairment, nonprogressive lesions, and persistence defines a group of children who were of interest to the researchers who developed the definition. Cerebral palsy as a definition does not attend to the broader issues of neurodevelopmental dysfunction. It isolates a portion of the spectrum of motor dysfunction and creates a category whose bounds are defined by a range of motor capability. The classifications of cerebral palsy that require revision are discussed. Some classifications should be discarded. Others should be brought in line with current knowledge and approaches. Still others should be modified to encompass the broader views of function and therapy that reflect the current expectations for persons with disabilities. PMID:15292880

  8. Improving VHF Spectrum Utilization

    NASA Technical Reports Server (NTRS)

    Andro, Monty; Orr, Richard; Foore, Larry; Sheehe, Charles; Freeman, Mark; Nguyen, Thanh; Bretmersky, Steven; Laberge, Chuck; Buchanan, David

    2004-01-01

    Limited VHF communications system capacity and increasing air traffic results in congestion of the aviation VHF spectrum. The voice communications errors and delayed channel access create system congestion and air traffic delays. Regulatory subdivision of bands for specific functions limits flexibility in the frequency usage. The objective of this viewgraph presentation is to identify near/mid/far term technologies to improve the performance and spectrum efficiency of current and emerging VHF communications systems. Select technologies with the highest potential, perform research and development to bring them to implementation stage.

  9. Energy distribution in the quantum spectrum

    NASA Astrophysics Data System (ADS)

    Bi, Siwen

    2015-11-01

    At first this paper summarizes the current situation and historical development of the spectrum research, the difficulties and demand background. Then it introduces the research status of quantum spectrum and research ideas of energy distribution in quantum spectrum. We explain the concept of quantum spectrum, the difference between quantum spectrum and spectrum. We elaborate energy distribution in quantum spectrum from three aspects, which are representation, feature and mechanism of quantum spectrum energy distribution. Finally we describe the application of monochrome quantum spectrum about imaging and detection aspects and give an overview of the quantum spectrum. Based on above research results we continue to study and achieve the detection of multi-spectral imaging, which provide the technical basis for the application. We try access to an advanced stage of quantum spectrum study as soon as possible.

  10. An approach to on-line electrospray mass spectrometric detection of polypeptide antibiotics of enramycin for high-speed counter-current chromatographic separation.

    PubMed

    Inoue, Koichi; Hattori, Yasuko; Hino, Tomoaki; Oka, Hisao

    2010-04-01

    In the field of pharmaceutical and biomedical analysis of peptides, a rapid on-line detection and identification for a methodology have been required for the discovery of new biological active products. In this study, a high-speed counter-current chromatography with electrospray mass spectrometry (HSCCC/ESI-MS) was developed for the on-line detection and purification of polypeptide antibiotics of enramycin-A and -B. The analytes were purified on HSCCC model CCC-1000 (multi-layer coil planet centrifuge) with a volatile solvent of two-phase system composed of n-butanol/hexane/0.05% aqueous trifluoroacetic acid solution (43/7/50, V/V/V), and detected on an LCMS-2010EV quadrupole mass spectrometer fitted with an ESI source system in positive ionization following scan mode (m/z 100-2000). The HSCCC/ESI-MS peaks indicated that enramycin-A (major m/z 786 [M+3H](3+) and minor m/z 1179 [M+2H](2+)) and enramycin-B (major m/z 791 [M+3H](3+) and minor m/z 1185 [M+2H](2+)) have the peak resolution value of 2.9 from 15mg of loaded enramycin powder. The HSCCC collected amounts of the peak fractions were additionally 4.3mg (enramycin-A), and 5.9mg (enramycin-B), respectively. These purified substances were analyzed by LC/ESI-MS with scan positive mode. Based on the LC/ESI-MS chromatograms and spectra of the fractions, enramycin-A and -B were estimated to be over 95% purity. The overall results indicate that this approach of HSCCC/ESI-MS is a powerful technique for the purification and identification of bioactive peptides. PMID:20004073

  11. Cyclotron Line Measurements with INTEGRAL

    NASA Technical Reports Server (NTRS)

    Pottschmidt, K.; Kreykenbohm, I.; Caballero, I.; Fritz, S.; Schoenherr, G.; Kretschmar, P.; Wilms, J.; McBride, V. A.; Suchy, S.; Rothschild, R. E.

    2008-01-01

    Due to its broadband energy coverage, INTEGRAL has made important contributions to observing and interpreting cyclotron lines, which are present in the 10-100 keV range of a sample of accreting pulsars. In these systems photons with energies fulfilling the resonance condition inelastically Compton scatter off electrons quantized in the accretion column above the neutron star's magnetic pole(s). This process gives rise to the broad, absorption-like lines or 'cyclotron resonant scattering features' (CRSF). The observed lines allow to directly measure the B-fields of these sources, resulting in values of a few times 1E12G. In this overview I will present recent highlights regarding CRSF observations as well as discuss current ideas and models for the physical conditions in the accretion column. Among the former are the stability of the spectrum of Vela X-1 during giant flares in 2003, the observation of three cyclotron lines during the 2004 outburst of V0332+53, the confirmation of the fundamental line at approximately 45 keV during a 2005 normal outburst of A0535-26, and the simultaneous detection of the two lines in the dipping source 4U 1907+09 (for which also a torque reversal was detected for the first time). Through these and other observations it has become increasingly apparent that two types of observations can potentially be used to constrain the accretion column geometry: the determination of energy ratios for multiple harmonic lines (only two sources with greater than 2 lines are known), was well as the evolution of the fundamental line centroid, which, for different sources, may or may not be correlated with flux. Furthermore, first steps have been taken away from the usual phenomenological description of the lines, towards a physical approach based on self-consistent CRSF modeling. Initial applications are presented.

  12. Observation of an Anomalous Line Shape of the η^{'}π^{+}π^{-} Mass Spectrum near the pp[over ¯] Mass Threshold in J/ψ→γη^{'}π^{+}π^{-}.

    PubMed

    Ablikim, M; Achasov, M N; Ahmed, S; Ai, X C; Albayrak, O; Albrecht, M; Ambrose, D J; Amoroso, A; An, F F; An, Q; Bai, J Z; Baldini Ferroli, R; Ban, Y; Bennett, D W; Bennett, J V; Berger, N; Bertani, M; Bettoni, D; Bian, J M; Bianchi, F; Boger, E; Boyko, I; Briere, R A; Cai, H; Cai, X; Cakir, O; Calcaterra, A; Cao, G F; Cetin, S A; Chang, J F; Chelkov, G; Chen, G; Chen, H S; Chen, H Y; Chen, J C; Chen, M L; Chen, S; Chen, S J; Chen, X; Chen, X R; Chen, Y B; Cheng, H P; Chu, X K; Cibinetto, G; Dai, H L; Dai, J P; Dbeyssi, A; Dedovich, D; Deng, Z Y; Denig, A; Denysenko, I; Destefanis, M; De Mori, F; Ding, Y; Dong, C; Dong, J; Dong, L Y; Dong, M Y; Dou, Z L; Du, S X; Duan, P F; Fan, J Z; Fang, J; Fang, S S; Fang, X; Fang, Y; Farinelli, R; Fava, L; Fedorov, O; Feldbauer, F; Felici, G; Feng, C Q; Fioravanti, E; Fritsch, M; Fu, C D; Gao, Q; Gao, X L; Gao, X Y; Gao, Y; Gao, Z; Garzia, I; Goetzen, K; Gong, L; Gong, W X; Gradl, W; Greco, M; Gu, M H; Gu, Y T; Guan, Y H; Guo, A Q; Guo, L B; Guo, R P; Guo, Y; Guo, Y P; Haddadi, Z; Hafner, A; Han, S; Hao, X Q; Harris, F A; He, K L; Heinsius, F H; Held, T; Heng, Y K; Holtmann, T; Hou, Z L; Hu, C; Hu, H M; Hu, J F; Hu, T; Hu, Y; Huang, G S; Huang, Y P; Huang, J S; Huang, X T; Huang, X Z; Huang, Y; Huang, Z L; Hussain, T; Ji, Q; Ji, Q P; Ji, X B; Ji, X L; Jiang, L W; Jiang, X S; Jiang, X Y; Jiao, J B; Jiao, Z; Jin, D P; Jin, S; Johansson, T; Julin, A; Kalantar-Nayestanaki, N; Kang, X L; Kang, X S; Kavatsyuk, M; Ke, B C; Kiese, P; Kliemt, R; Kloss, B; Kolcu, O B; Kopf, B; Kornicer, M; Kupsc, A; Kühn, W; Lange, J S; Lara, M; Larin, P; Leithoff, H; Leng, C; Li, C; Li, Cheng; Li, D M; Li, F; Li, F Y; Li, G; Li, H B; Li, H J; Li, J C; Li, Jin; Li, K; Li, K; Li, Lei; Li, P R; Li, Q Y; Li, T; Li, W D; Li, W G; Li, X L; Li, X N; Li, X Q; Li, Y B; Li, Z B; Liang, H; Liang, Y F; Liang, Y T; Liao, G R; Lin, D X; Liu, B; Liu, B J; Liu, C X; Liu, D; Liu, F H; Liu, Fang; Liu, Feng; Liu, H B; Liu, H H; Liu, H H; Liu, H M; Liu, J; Liu, J B; Liu, J P; Liu, J Y; Liu, K; Liu, K Y; Liu, L D; Liu, P L; Liu, Q; Liu, S B; Liu, X; Liu, Y B; Liu, Y Y; Liu, Z A; Liu, Zhiqing; Loehner, H; Lou, X C; Lu, H J; Lu, J G; Lu, Y; Lu, Y P; Luo, C L; Luo, M X; Luo, T; Luo, X L; Lyu, X R; Ma, F C; Ma, H L; Ma, L L; Ma, M M; Ma, Q M; Ma, T; Ma, X N; Ma, X Y; Ma, Y M; Maas, F E; Maggiora, M; Malik, Q A; Mao, Y J; Mao, Z P; Marcello, S; Messchendorp, J G; Mezzadri, G; Min, J; Min, T J; Mitchell, R E; Mo, X H; Mo, Y J; Morales Morales, C; Muchnoi, N Yu; Muramatsu, H; Musiol, P; Nefedov, Y; Nerling, F; Nikolaev, I B; Ning, Z; Nisar, S; Niu, S L; Niu, X Y; Olsen, S L; Ouyang, Q; Pacetti, S; Pan, Y; Patteri, P; Pelizaeus, M; Peng, H P; Peters, K; Pettersson, J; Ping, J L; Ping, R G; Poling, R; Prasad, V; Qi, H R; Qi, M; Qian, S; Qiao, C F; Qin, L Q; Qin, N; Qin, X S; Qin, Z H; Qiu, J F; Rashid, K H; Redmer, C F; Ripka, M; Rong, G; Rosner, Ch; Ruan, X D; Sarantsev, A; Savrié, M; Schnier, C; Schoenning, K; Schumann, S; Shan, W; Shao, M; Shen, C P; Shen, P X; Shen, X Y; Sheng, H Y; Shi, M; Song, W M; Song, X Y; Sosio, S; Spataro, S; Sun, G X; Sun, J F; Sun, S S; Sun, X H; Sun, Y J; Sun, Y Z; Sun, Z J; Sun, Z T; Tang, C J; Tang, X; Tapan, I; Thorndike, E H; Tiemens, M; Uman, I; Varner, G S; Wang, B; Wang, B L; Wang, D; Wang, D Y; Wang, K; Wang, L L; Wang, L S; Wang, M; Wang, P; Wang, P L; Wang, S G; Wang, W; Wang, W P; Wang, X F; Wang, Y; Wang, Y D; Wang, Y F; Wang, Y Q; Wang, Z; Wang, Z G; Wang, Z H; Wang, Z Y; Wang, Z Y; Weber, T; Wei, D H; Wei, J B; Weidenkaff, P; Wen, S P; Wiedner, U; Wolke, M; Wu, L H; Wu, L J; Wu, Z; Xia, L; Xia, L G; Xia, Y; Xiao, D; Xiao, H; Xiao, Z J; Xie, Y G; Xiu, Q L; Xu, G F; Xu, J J; Xu, L; Xu, Q J; Xu, Q N; Xu, X P; Yan, L; Yan, W B; Yan, W C; Yan, Y H; Yang, H J; Yang, H X; Yang, L; Yang, Y X; Ye, M; Ye, M H; Yin, J H; Yu, B X; Yu, C X; Yu, J S; Yuan, C Z; Yuan, W L; Yuan, Y; Yuncu, A; Zafar, A A; Zallo, A; Zeng, Y; Zeng, Z; Zhang, B X; Zhang, B Y; Zhang, C; Zhang, C C; Zhang, D H; Zhang, H H; Zhang, H Y; Zhang, J; Zhang, J J; Zhang, J L; Zhang, J Q; Zhang, J W; Zhang, J Y; Zhang, J Z; Zhang, K; Zhang, L; Zhang, S Q; Zhang, X Y; Zhang, Y; Zhang, Y H; Zhang, Y N; Zhang, Y T; Zhang, Yu; Zhang, Z H; Zhang, Z P; Zhang, Z Y; Zhao, G; Zhao, J W; Zhao, J Y; Zhao, J Z; Zhao, Lei; Zhao, Ling; Zhao, M G; Zhao, Q; Zhao, Q W; Zhao, S J; Zhao, T C; Zhao, Y B; Zhao, Z G; Zhemchugov, A; Zheng, B; Zheng, J P; Zheng, W J; Zheng, Y H; Zhong, B; Zhou, L; Zhou, X; Zhou, X K; Zhou, X R; Zhou, X Y; Zhu, K; Zhu, K J; Zhu, S; Zhu, S H; Zhu, X L; Zhu, Y C; Zhu, Y S; Zhu, Z A; Zhuang, J; Zotti, L; Zou, B S; Zou, J H

    2016-07-22

    Using 1.09×10^{9} J/ψ events collected by the BESIII experiment in 2012, we study the J/ψ→γη^{'}π^{+}π^{-} process and observe a significant abrupt change in the slope of the η^{'}π^{+}π^{-} invariant mass distribution at the proton-antiproton (pp[over ¯]) mass threshold. We use two models to characterize the η^{'}π^{+}π^{-} line shape around 1.85  GeV/c^{2}: one that explicitly incorporates the opening of a decay threshold in the mass spectrum (Flatté formula), and another that is the coherent sum of two resonant amplitudes. Both fits show almost equally good agreement with data, and suggest the existence of either a broad state around 1.85  GeV/c^{2} with strong couplings to the pp[over ¯] final states or a narrow state just below the pp[over ¯] mass threshold. Although we cannot distinguish between the fits, either one supports the existence of a pp[over ¯] moleculelike state or bound state with greater than 7σ significance. PMID:27494467

  13. Emission lines from hot astrophysical plasmas

    NASA Astrophysics Data System (ADS)

    Raymond, John C.

    The spectral lines which dominate the X-ray emission of hot, optically thin astrophysical plasmas reflect the elemental abundances, temperature distribution, and other physical parameters of the emitting gas. The accuracy and level of detail with which these parameters can be inferred are limited by the measurement uncertainties and uncertainties in atomic rates used to compute the model spectrum. This paper discusses the relative importance and the likely uncertainties in the various atomic rates and the likely uncertainties in the overall ionization balance and spectral line emissivities predicted by the computer codes currently used to fit X-ray spectral data.

  14. Airborne Fraunhofer Line Discriminator

    NASA Technical Reports Server (NTRS)

    Gabriel, F. C.; Markle, D. A.

    1969-01-01

    Airborne Fraunhofer Line Discriminator enables prospecting for fluorescent materials, hydrography with fluorescent dyes, and plant studies based on fluorescence of chlorophyll. Optical unit design is the coincidence of Fraunhofer lines in the solar spectrum occurring at the characteristic wavelengths of some fluorescent materials.

  15. Sensors across the Spectrum

    NASA Astrophysics Data System (ADS)

    Neese, Christopher F.; De Lucia, Frank C.; Medvedev, Ivan R.

    2011-06-01

    A resurgence of interest in spectroscopic sensors has been fueled by increases in performance made possible by technological advancements and applications in medicine, environmental monitoring, and national security. Often this research is technology driven, without enough consideration of the spectroscopic signatures available to be probed. We will compare several current spectroscopic sensors across the electromagnetic spectrum, with an eye towards the fundamental spectroscopic considerations important at each wavelength.

  16. Toward full spectrum speciation of silver nanoparticles and ionic silver by on-line coupling of hollow fiber flow field-flow fractionation and minicolumn concentration with multiple detectors.

    PubMed

    Tan, Zhi-Qiang; Liu, Jing-Fu; Guo, Xiao-Ru; Yin, Yong-Guang; Byeon, Seul Kee; Moon, Myeong Hee; Jiang, Gui-Bin

    2015-08-18

    The intertransformation of silver nanoparticles (AgNPs) and ionic silver (Ag(I)) in the environment determines their transport, uptake, and toxicity, demanding methods to simultaneously separate and quantify AgNPs and Ag(I). For the first time, hollow fiber flow field-flow fractionation (HF5) and minicolumn concentration were on-line coupled together with multiple detectors (including UV-vis spectrometry, dynamic light scattering, and inductively coupled plasma mass spectrometry) for full spectrum separation, characterization, and quantification of various Ag(I) species (i.e., free Ag(I), weak and strong Ag(I) complexes) and differently sized AgNPs. While HF5 was employed for filtration and fractionation of AgNPs (>2 nm), the minicolumn packed with Amberlite IR120 resin functioned to trap free Ag(I) or weak Ag(I) complexes coming from the radial flow of HF5 together with the strong Ag(I) complexes and tiny AgNPs (<2 nm), which were further discriminated in a second run of focusing by oxidizing >90% of tiny AgNPs to free Ag(I) and trapped in the minicolumn. The excellent performance was verified by the good agreement of the characterization results of AgNPs determined by this method with that by transmission electron microscopy, and the satisfactory recoveries (70.7-108%) for seven Ag species, including Ag(I), the adduct of Ag(I) and cysteine, and five AgNPs with nominal diameters of 1.4 nm, 10 nm, 20 nm, 40 nm, and 60 nm in surface water samples. PMID:26222150

  17. Parametic Study of the current limit within a single driver-scaletransport beam line of an induction Linac for Heavy Ion Fusion

    SciTech Connect

    Prost, Lionel Robert

    2007-02-14

    The High Current Experiment (HCX) at Lawrence Berkeley National Laboratory is part of the US program that explores heavy-ion beam as the driver option for fusion energy production in an Inertial Fusion Energy (IFE) plant. The HCX is a beam transport experiment at a scale representative of the low-energy end of an induction linear accelerator driver. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge-dominated heavy-ion beams at high intensity (line charge density {approx}0.2 {micro}C/m) over long pulse durations (4 {micro}s) in alternating gradient focusing lattices of electrostatic or magnetic quadrupoles. This experiment is testing transport issues resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and steering, envelope matching, image charges and focusing field nonlinearities, halo and, electron and gas cloud effects. We present the results for a coasting 1 MeV K{sup +} ion beam transported through ten electrostatic quadrupoles. The measurements cover two different fill factor studies (60% and 80% of the clear aperture radius) for which the transverse phase-space of the beam was characterized in detail, along with beam energy measurements and the first halo measurements. Electrostatic quadrupole transport at high beam fill factor ({approx}80%) is achieved with acceptable emittance growth and beam loss. We achieved good envelope control, and re-matching may only be needed every ten lattice periods (at 80% fill factor) in a longer lattice of similar design. We also show that understanding and controlling the time dependence of the envelope parameters is critical to achieving high fill factors, notably because of the injector and matching section dynamics.

  18. Battlefield spectrum management

    NASA Astrophysics Data System (ADS)

    Sivakumar, C.

    1997-06-01

    Modern tactical communications systems rely on radios to support network and user connectivity. One of the challenges for network planners and managers is to make best use of scarce and vulnerable frequency spectrum resources to support the communication needs of war fighters. With the wide variety of Iris radio types typically to be deployed in the battlefield (ranging from high frequency to super high frequency), a comprehensive suite of tools is necessary to ensure that frequency interference is kept minimum. Without a sophisticated frequency spectrum management system, the most advanced tactical communications systems could be rendered useless, jeopardizing human life and national security. For these reasons, it is important to develop an Iris wide battlefield spectrum management capability that takes full advantage of current frequency spectrum management research and development (R&D), related tools, and supporting technology for assigning frequencies. This session briefly describes various assignment strategies being adopted in the Iris BFSM for overcoming cosite/collocated/farsite interferences along with the propagation models [from high frequency (HF) to super high frequency (SHF)] used for the assignment of frequencies. Also a brief thread outlining the process for generating frequency allocation/assignment request and analysis of frequency interference is discussed.

  19. Broad-spectrum antiviral agents

    PubMed Central

    Zhu, Jun-Da; Meng, Wen; Wang, Xiao-Jia; Wang, Hwa-Chain R.

    2015-01-01

    Development of highly effective, broad-spectrum antiviral agents is the major objective shared by the fields of virology and pharmaceutics. Antiviral drug development has focused on targeting viral entry and replication, as well as modulating cellular defense system. High throughput screening of molecules, genetic engineering of peptides, and functional screening of agents have identified promising candidates for development of optimal broad-spectrum antiviral agents to intervene in viral infection and control viral epidemics. This review discusses current knowledge, prospective applications, opportunities, and challenges in the development of broad-spectrum antiviral agents. PMID:26052325

  20. Influence of the finite linewidth of the laser radiation spectrum on the shape of the coherent population trapping resonance line in an optically dense medium with a buffer gas

    SciTech Connect

    Barantsev, K. A. Popov, E. N.; Litvinov, A. N.

    2015-11-15

    The theory of coherent population trapping resonance is developed for the finite linewidth of the laser radiation spectrum in an optically dense medium of Λ atoms in a cell with a buffer gas. Equations are derived for the atomic density matrix and laser emission spectrum transfer in a cell with working and buffer gases at a finite temperature. The dependence of the quality factor of coherent population trapping resonance on the linewidth of the laser radiation spectrum is studied by measuring transmitted radiation and fluorescence signals.

  1. Spectrum of anomalous magnetohydrodynamics

    NASA Astrophysics Data System (ADS)

    Giovannini, Massimo

    2016-05-01

    The equations of anomalous magnetohydrodynamics describe an Abelian plasma where conduction and chiral currents are simultaneously present and constrained by the second law of thermodynamics. At high frequencies the magnetic currents play the leading role, and the spectrum is dominated by two-fluid effects. The system behaves instead as a single fluid in the low-frequency regime where the vortical currents induce potentially large hypermagnetic fields. After deriving the physical solutions of the generalized Appleton-Hartree equation, the corresponding dispersion relations are scrutinized and compared with the results valid for cold plasmas. Hypermagnetic knots and fluid vortices can be concurrently present at very low frequencies and suggest a qualitatively different dynamics of the hydromagnetic nonlinearities.

  2. Autism Spectrum Disorder

    MedlinePlus

    ... Awards Enhancing Diversity Find People About NINDS NINDS Autism Spectrum Disorder Information Page Condensed from Autism Spectrum ... en Español Additional resources from MedlinePlus What is Autism Spectrum Disorder? Autistic disorder (sometimes called autism or ...

  3. On Removing Interloper Contamination from Intensity Mapping Power Spectrum Measurements

    NASA Astrophysics Data System (ADS)

    Lidz, Adam; Taylor, Jessie

    2016-07-01

    Line intensity mapping experiments seek to trace large-scale structures by measuring the spatial fluctuations in the combined emission, in some convenient spectral line, from individually unresolved galaxies. An important systematic concern for these surveys is line confusion from foreground or background galaxies emitting in other lines that happen to lie at the same observed frequency as the “target” emission line of interest. We develop an approach to separate this “interloper” emission at the power spectrum level. If one adopts the redshift of the target emission line in mapping from observed frequency and angle on the sky to co-moving units, the interloper emission is mapped to the wrong co-moving coordinates. Because the mapping is different in the line of sight and transverse directions, the interloper contribution to the power spectrum becomes anisotropic, especially if the interloper and target emission are at widely separated redshifts. This distortion is analogous to the Alcock–Paczynski test, but here the warping arises from assuming the wrong redshift rather than an incorrect cosmological model. We apply this to the case of a hypothetical [C ii] emission survey at z∼ 7 and find that the distinctive interloper anisotropy can, in principle, be used to separate strong foreground CO emission fluctuations. In our models, however, a significantly more sensitive instrument than currently planned is required, although there are large uncertainties in forecasting the high-redshift [C ii] emission signal. With upcoming surveys, it may nevertheless be useful to apply this approach after first masking pixels suspected of containing strong interloper contamination.

  4. On Removing Interloper Contamination from Intensity Mapping Power Spectrum Measurements

    NASA Astrophysics Data System (ADS)

    Lidz, Adam; Taylor, Jessie

    2016-07-01

    Line intensity mapping experiments seek to trace large-scale structures by measuring the spatial fluctuations in the combined emission, in some convenient spectral line, from individually unresolved galaxies. An important systematic concern for these surveys is line confusion from foreground or background galaxies emitting in other lines that happen to lie at the same observed frequency as the “target” emission line of interest. We develop an approach to separate this “interloper” emission at the power spectrum level. If one adopts the redshift of the target emission line in mapping from observed frequency and angle on the sky to co-moving units, the interloper emission is mapped to the wrong co-moving coordinates. Because the mapping is different in the line of sight and transverse directions, the interloper contribution to the power spectrum becomes anisotropic, especially if the interloper and target emission are at widely separated redshifts. This distortion is analogous to the Alcock–Paczynski test, but here the warping arises from assuming the wrong redshift rather than an incorrect cosmological model. We apply this to the case of a hypothetical [C ii] emission survey at z˜ 7 and find that the distinctive interloper anisotropy can, in principle, be used to separate strong foreground CO emission fluctuations. In our models, however, a significantly more sensitive instrument than currently planned is required, although there are large uncertainties in forecasting the high-redshift [C ii] emission signal. With upcoming surveys, it may nevertheless be useful to apply this approach after first masking pixels suspected of containing strong interloper contamination.

  5. Separation of five compounds from leaves of Andrographis paniculata (Burm. f.) Nees by off-line two-dimensional high-speed counter-current chromatography combined with gradient and recycling elution.

    PubMed

    Zhang, Li; Liu, Qi; Yu, Jingang; Zeng, Hualiang; Jiang, Shujing; Chen, Xiaoqing

    2015-05-01

    An off-line two-dimensional high-speed counter-current chromatography method combined with gradient and recycling elution mode was established to isolate terpenoids and flavones from the leaves of Andrographis paniculata (Burm. f.) Nees. By using the solvent systems composed of n-hexane/ethyl acetate/methanol/water with different volume ratios, five compounds including roseooside, 5,4'-dihydroxyflavonoid-7-O-β-d-pyranglucuronatebutylester, 7,8-dimethoxy-2'-hydroxy-5-O-β-d-glucopyranosyloxyflavon, 14-deoxyandrographiside, and andrographolide were successfully isolated. Purities of these isolated compounds were all over 95% as determined by high-performance liquid chromatography. Their structures were identified by UV, mass spectrometry, and (1) H NMR spectroscopy. It has been demonstrated that the combination of off-line two-dimensional high-speed counter-current chromatography with different elution modes is an efficient technique to isolate compounds from complex natural product extracts. PMID:25675944

  6. Critical current density, irreversibility line, and flux creep activation energy in silver-sheathed Bi[sub 2]Sr[sub 2]Ca[sub 2]Cu[sub 3]O[sub x] superconducting tapes

    SciTech Connect

    Shi, D.; Wang, Z.; Sengupta, S.; Smith, M. ); Goodrich, L.F. , Boulder, CO . Electromagnetic Technology Div.); Dou, S.X.; Liu, H.K.; Guo, Y.C. . School of Materials and Engineering)

    1992-08-01

    Transport data, magnetic hysteresis and flux creep activation energy experimental results are presented for silver-sheathed high-[Tc] Bi[sub 2]Sr[sub 2]Ca[sub 2]Cu[sub 3]O[sub x] superconducting tapes. The 110 K superconducting phase was formed by lead doping in a Bi-Sr-Ca-Cu-0 system. The transport critical current density was measured at 4.0 K to be 0.7 [times] 10[sup 5] A/cm[sup 2] (the corresponding critical current is 74 A) at zero field and 1.6 [times] 10[sup 4] A/cm[sup 2] at 12 T for H[parallel]ab. Excellent grain alignment in the a-b plane was achieved by a short-melting method, which considerably improved the critical current density and irreversibility line. Flux creep activation energy as a function of current is obtained based on the magnetic relaxation measurements.

  7. Critical current density, irreversibility line, and flux creep activation energy in silver-sheathed Bi{sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} superconducting tapes

    SciTech Connect

    Shi, D.; Wang, Z.; Sengupta, S.; Smith, M.; Goodrich, L.F.; Dou, S.X.; Liu, H.K.; Guo, Y.C.

    1992-08-01

    Transport data, magnetic hysteresis and flux creep activation energy experimental results are presented for silver-sheathed high-{Tc} Bi{sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} superconducting tapes. The 110 K superconducting phase was formed by lead doping in a Bi-Sr-Ca-Cu-0 system. The transport critical current density was measured at 4.0 K to be 0.7 {times} 10{sup 5} A/cm{sup 2} (the corresponding critical current is 74 A) at zero field and 1.6 {times} 10{sup 4} A/cm{sup 2} at 12 T for H{parallel}ab. Excellent grain alignment in the a-b plane was achieved by a short-melting method, which considerably improved the critical current density and irreversibility line. Flux creep activation energy as a function of current is obtained based on the magnetic relaxation measurements.

  8. Autism Spectrum Disorders in Africa: Current Challenges in Identification, Assessment, and Treatment: A Report on the International Child Neurology Association Meeting on ASD in Africa, Ghana, April 3-5, 2014.

    PubMed

    Ruparelia, Kavita; Abubakar, Amina; Badoe, Eben; Bakare, Muideen; Visser, Karren; Chugani, Diane C; Chugani, Harry T; Donald, Kirsten A; Wilmshurst, Jo M; Shih, Andy; Skuse, David; Newton, Charles R

    2016-07-01

    Prevalence of autism spectrum disorders has increased over recent years, however, little is known about the identification and management of autism spectrum disorder in Africa. This report summarizes a workshop on autism spectrum disorder in Africa under the auspices of the International Child Neurology Association and the African Child Neurology Association through guided presentations and working group reports, focusing on identification, diagnosis, management, and community support. A total of 47 delegates participated from 14 African countries. Although there was a huge variability in services across the countries represented, numbers of specialists assessing and managing autism spectrum disorder was small relative to populations served. Strategies were proposed to improve identification, diagnosis, management and support delivery for individuals with autism spectrum disorder across Africa in these culturally diverse, low-resource settings. Emphasis on raising public awareness through community engagement and improving access to information and training in autism spectrum disorder. Special considerations for the cultural, linguistic, and socioeconomic factors within Africa are discussed. PMID:26979098

  9. A 2009 July 28 fireball spectrum

    NASA Astrophysics Data System (ADS)

    Kac, Javor; Govedic, Mitja

    2010-01-01

    A sensitive video CCTV camera was used with the diffraction grating to record meteor spectra. On 2009 July 28 at 22h59m39s UT, a second-order spectrum of a bright fireball was recorded. Eighteen emission lines were identified, with the major lines corresponding to magnesium, calcium, iron and sodium. Only four faint emission lines could be attributed to the atmospheric elements, probably due to the low meteor atmospheric velocity.

  10. The Near-Infrared Coronal Spectrum

    NASA Astrophysics Data System (ADS)

    Kuhn, J. R.; Penn, M. J.; Mann, I.

    1996-01-01

    Sensitive measurements of the near-infrared coronal spectrum were obtained from the 1994 total solar eclipse. A new [S IX] emission line at 1.25249 +/- 0.00003 mu m has been detected, and a bright, potentially important diagnostic, [Si X] line at 1.43 mu m has been confirmed. Upper limits on the intensity of several other predicted IR emission lines have been established. Also, diffuse He I emission, perhaps geocoronal, has been observed with a significant heliocentric redshift.

  11. Birds on power lines

    NASA Astrophysics Data System (ADS)

    Arnaldo Redinz, José

    2014-07-01

    Why can a bird safely rest on a high-voltage power line? We discuss three effects that can lead to the development of voltages and currents in the bird's body. To explain the absence of electric shocks, we give numerical estimates of these voltages and currents obtained from the standard solution for the voltage along a two-wire transmission line.

  12. Neurofeedback in Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Holtmann, Martin; Steiner, Sabina; Hohmann, Sarah; Poustka, Luise; Banaschewski, Tobias; Bolte, Sven

    2011-01-01

    Aim: To review current studies on the effectiveness of neurofeedback as a method of treatment of the core symptoms of autism spectrum disorders (ASD). Method: Studies were selected based on searches in PubMed, Ovid MEDLINE, EMBASE, ERIC, and CINAHL using combinations of the following keywords: "Neurofeedback" OR "EEG Biofeedback" OR "Neurotherapy"…

  13. Scaling properties of the anisotropic critical current density in bulk textured YBaCuO. Evidence toward a 3D flux line lattice

    SciTech Connect

    Braithwaite, D.; Bourgault, D.; Sulpice, A.; Barbut, J.M.; Tournier, R. l'Universite Joseph Fourier, Grenoble ); Monot, I.; Lepropre, M.; Provost, J.; Desgardin, G. )

    1993-04-01

    The dc transport critical current densities of melt texture grown and magnetically melt textured bulk YBaCuO have been measured at 77 K and in magnetic fields. A maximum value of over 31,000 A/cm[sup 2] is obtained with a field of 7 teslas applied parallel to the (a,b) planes. Over the rest of the angular range the critical current is shown to be determined mainly by the c-axis component of the applied field. Although this dependency is expected in the presence of two-dimensional vortices, in fact the data are shown to correspond better to the behavior expected of an anisotropic three-dimensional superconductor. These results are compared to magnetization measurements on the same samples. Results show that when the field is directed close to the c-axis, superconducting transport currents flow at fields well above the field at which the irreversible magnetization disappears.

  14. Overview spectra and axial distribution of spectral line intensities in a high-current vacuum arc with CuCr electrodes

    SciTech Connect

    Lisnyak, M.; Pipa, A. V.; Gorchakov, S. E-mail: weltmann@inp-greifswald.de; Iseni, S.; Franke, St.; Khapour, A.; Methling, R.; Weltmann, K.-D. E-mail: weltmann@inp-greifswald.de

    2015-09-28

    Spectroscopic investigations of free-burning vacuum arcs in diffuse mode with CuCr electrodes are presented. The experimental conditions of the investigated arc correspond to the typical system for vacuum circuit breakers. Spectra of six species Cu I, Cu II, Cu III, Cr I, Cr II, and Cr III have been analyzed in the wavelength range 350–810 nm. The axial intensity distributions were found to be strongly dependent on the ionization stage of radiating species. Emission distributions of Cr II and Cu II can be distinguished as well as the distributions of Cr III and Cu III. Information on the axial distribution was used to identify the spectra and for identification of overlapping spectral lines. The overview spectra and some spectral windows recorded with high resolution are presented. Analysis of axial distributions of emitted light, which originates from different ionization states, is presented and discussed.

  15. Maternal Depressive Symptoms following Autism Spectrum Diagnosis

    ERIC Educational Resources Information Center

    Taylor, Julie Lounds; Warren, Zachary E.

    2012-01-01

    The current study examined depressive symptoms, concerning the week following autism spectrum diagnosis and an average of 1.4 years later, in mothers (n = 75) of young children diagnosed with an autism spectrum disorder (ASD). Over three-quarters of mothers (78.7%) provided retrospective reports of clinically significant depressive symptoms…

  16. Autism Spectrum Disorders

    PubMed Central

    Hyman, Mark; Swift, Kathie

    2012-01-01

    Autism spectrum disorders (ASDs) are collectively the most commonly diagnosed pediatric neurodevelopmental condition. ASDs include autism, pervasive developmental disorder-not otherwise specified (PDD-NOS), Rett syndrome and Asperger disorder. ASD is characterized by impaired communication and social interaction and may involve developmental delays and seizure disorders. Recent parent-reported diagnosis of ASD in the United States put it at higher levels (1:91) than previously thought, with its diagnosis in boys occurring 4 to 5 times more frequently than in girls (1:58).1 CDC estimates are currently 1:110;1 up from 1:150 in 2007.2 Annual medical expenditures for those affected are generally four to six times greater than for those without ASD.1 While twin studies demonstrate that genetics play a significant role in ASD, the impact of environment should not be underestimated, given the approximate 20-fold increase in incidence over the last 20 years.3 PMID:24278834

  17. Neuromyelitis optica spectrum disorders.

    PubMed

    Wingerchuk, Dean M

    2010-10-01

    Neuromyelitis optica is an uncommon inflammatory demyelinating CNS disorder that is distinct from multiple sclerosis with respect to clinical, laboratory, neuroimaging, and prognostic characteristics. Autoantibodies that target aquaporin-4 are highly specific for neuromyelitis optica and have helped define a spectrum of disease beyond the classic definition of acute transverse myelitis and optic neuritis. Accumulating evidence supports the pathogenic potential that these autoantibodies possess in relation to the unique vasculocentric immunopathology of the disease. Current treatment strategies therefore include the use of corticosteroids and plasmapheresis for acute attacks and general or humoral immunosuppression for attack prevention. Ongoing research will focus on establishing the pathogenic mechanisms of the disease, in part derived from newly reported animal models, and testing-focused treatment strategies that evolve from this knowledge. PMID:22810601

  18. Line spectrum and ion temperature measurements from tungsten ions at low ionization stages in large helical device based on vacuum ultraviolet spectroscopy in wavelength range of 500–2200 Å

    SciTech Connect

    Oishi, T. Morita, S.; Goto, M.; Huang, X. L.; Zhang, H. M.

    2014-11-15

    Vacuum ultraviolet spectra of emissions released from tungsten ions at lower ionization stages were measured in the Large Helical Device (LHD) in the wavelength range of 500–2200 Å using a 3 m normal incidence spectrometer. Tungsten ions were distributed in the LHD plasma by injecting a pellet consisting of a small piece of tungsten metal and polyethylene tube. Many lines having different wavelengths from intrinsic impurity ions were observed just after the tungsten pellet injection. Doppler broadening of a tungsten candidate line was successfully measured and the ion temperature was obtained.

  19. Flux line lattice disorder induced by pinning centers and critical currents in YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}

    SciTech Connect

    Pan, V.M.; Solovjov, V.F.; Freyhardt, H.C.

    1997-06-01

    Angular dependencies of the critical current density and the irreversible magnetization for single-crystalline and single-domain-melt-textured samples of moderately anisotropic high-T{sub c} superconductor YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} (YBCO) are measured both with transport current and magnetic techniques in the range of temperature between 77.6 K and T{sub c} and applied magnetic field up to 2 T. It is proven that the {open_quotes}cleaner{close_quotes} YBCO single crystals with no dopants and/or fine precipitates show higher critical current densities than melt-textured YBCO materials: J{sub c} up to {approximately}5.5{circ}10{sup 4} A/cm{sup 2} at 77.6 K, {mu}{sub 0}H= 1.5 T and the angle {Theta} between H and C-axis {approx}{+-}20{degrees}. It is also shown the main contribution to the net J{sub c} comes from the oxygen vacancies. The twin boundaries dramatically reduce J{sub c} at orientations close to H{parallel}C (within {+-} 20{degrees} deviation) and at intermediate values of applied field. J{sub c} (H{parallel}C) at 77.6 K and 1.5 T equals to 1.5{circ}10{sup 4} A/cm{sup 2} against 5.5{circ}10{sup 4} A/cm{sup 2} at H inclined with 6-20{degrees} angle. Thus, in contrast to melt-textured samples the J{sub c}({Theta}) dependencies for twinned single crystals reveal a remarkable minimum at H{parallel}C-axis orientation (corresponds to {Theta}=0). This angular dependence of the J{sub c} results from a combination of two contributions into the volume pinning force, F{sub p}: from point-like and planar pis. The random point-like defects are responsible for the major part of measured J{sub c} anisotropy. The role of the twin planes as extended defects, which provide a vortex locking proves out to be more ambiguous due to interference of the correlated disorder induced by the twins with point-like one, induced by the oxygen vacancies. The authors also consider influence of the defect structure of YBCO samples on dynamic properties of the FLL.

  20. Autism Spectrum Disorder

    MedlinePlus

    Autism spectrum disorder (ASD) is a neurological and developmental disorder that begins early in childhood and lasts throughout a ... and pervasive developmental disorders. It is called a "spectrum" disorder because people with ASD can have a ...

  1. Autism Spectrum Disorder (ASD)

    MedlinePlus

    ... spectrum disorder (ASD) is a group of developmental disabilities that can cause significant social, communication and behavioral ... for autism spectrum disorder (ASD) and other developmental disabilities. More E-mail Your Friends "Children with autism ...

  2. Determining the Current and Future Health of Low-Latitude Andean Glaciers Using an Equilibrium Line Altitude Model and Hypsometric Data from the Randolph Glacier Inventory

    NASA Astrophysics Data System (ADS)

    Malone, A.; MacAyeal, D. R.

    2015-12-01

    Mountain glaciers have been described as the water towers of world, and for many populations in the low-latitude South American Andes, glacial runoff is vital for agricultural, industrial, and basic water needs. Previous studies of low-latitude Andean glaciers suggest a precarious future due to contemporary warming. These studies have looked at trends in freezing level heights or observations of contemporary retreat. However, regional-scale understanding of low-latitude glacial responses to present and future climate change is limited, in part due to incomplete information about the extent and elevation distribution of low-latitude glaciers. The recently published Randolph Glacier Inventory (RGI) (5.0) provides the necessary information about the size and elevation distribution of low-latitude glaciers to begin such studies. We determine the contemporary equilibrium line altitudes (ELAs) for low-latitude Andean glaciers in the RGI, using a numerical energy balance ablation model driven with reanalysis and gridded data products. Contemporary ELAs tend to fall around the peak of the elevation histogram, with an exception being the southern-most outer tropical glaciers whose modeled ELAs tend to be higher than the elevation histogram for that region (see below figure). Also, we use the linear tends in temperature and precipitation from the contemporary climatology to extrapolate 21stcentury climate forcings. Modeled ELAs by the middle on the century are universally predicted to rise, with outer tropical ELAs rising more than the inner tropical glaciers. These trends continue through the end of the century. Finally, we explore how climate variables and parameters in our numerical model may vary for different warming scenarios from United Nation's IPCC AR5 report. We quantify the impacts of these changes on ELAs for various climate change trajectories. These results support previous work on the precarious future of low latitude Andean glaciers, while providing a richer

  3. Cell Lines

    PubMed Central

    Cherbas, Lucy; Gong, Lei

    2014-01-01

    We review the properties and uses of cell lines in Drosophila research, emphasizing the variety of lines, the large body of genomic and transcriptional data available for many of the lines, and the variety of ways the lines have been used to provide tools for and insights into the developmental, molecular, and cell biology of Drosophila and mammals. PMID:24434506

  4. Modelling the TSZ power spectrum

    SciTech Connect

    Bhattacharya, Suman; Shaw, Laurie D; Nagai, Daisuke

    2010-01-01

    The structure formation in university is a hierarchical process. As universe evolves, tiny density fluctuations that existed in the early universe grows under gravitational instability to form massive large scale structures. The galaxy clusters are the massive viralized objects that forms by accreting smaller clumps of mass until they collapse under their self-gravity. As such galaxy clusters are the youngest objects in the universe which makes their abundance as a function of mass and redshift, very sensitive to dark energy. Galaxy clusters can be detected by measuring the richness in optical waveband, by measuring the X-ray flux, and in the microwave sky using Sunyaev-Zel'dovich (SZ) effect. The Sunyaev-Zel'dovich (SZ) effect has long been recognized as a powerful tool for detecting clusters and probing the physics of the intra-cluster medium. Ongoing and future experiments like Atacama Cosmology Telescope, the South Pole Telescope and Planck survey are currently surveying the microwave sky to develop large catalogs of galaxy clusters that are uniformly selected by the SZ flux. However one major systematic uncertainties that cluster abundance is prone to is the connection between the cluster mass and the SZ flux. As shown by several simulation studies, the scatter and bias in the SZ flux-mass relation can be a potential source of systematic error to using clusters as a cosmology probe. In this study they take a semi-analytic approach for modeling the intra-cluster medium in order to predict the tSZ power spectrum. The advantage of this approach is, being analytic, one can vary the parameters describing gas physics and cosmology simultaneously. The model can be calibrated against X-ray observations of massive, low-z clusters, and using the SZ power spectrum which is sourced by high-z lower mass galaxy groups. This approach allows us to include the uncertainty in gas physics, as dictated by the current observational uncertainties, while measuring the cosmological

  5. RF current sensor

    DOEpatents

    Moore, James A.; Sparks, Dennis O.

    1998-11-10

    An RF sensor having a novel current sensing probe and a voltage sensing probe to measure voltage and current. The current sensor is disposed in a transmission line to link all of the flux generated by the flowing current in order to obtain an accurate measurement. The voltage sensor is a flat plate which operates as a capacitive plate to sense voltage on a center conductor of the transmission line, in which the measured voltage is obtained across a resistance leg of a R-C differentiator circuit formed by the characteristic impedance of a connecting transmission line and a capacitance of the plate, which is positioned proximal to the center conductor.

  6. Teaching Braille Line Tracking Using Stimulus Fading

    ERIC Educational Resources Information Center

    Scheithauer, Mindy C.; Tiger, Jeffrey H.

    2014-01-01

    Line tracking is a prerequisite skill for braille literacy that involves moving one's finger horizontally across a line of braille text and identifying when a line ends so the reader may reset his or her finger on the subsequent line. Current procedures for teaching line tracking are incomplete, because they focus on tracking lines with only…

  7. Accelerating Spectrum Sharing Technologies

    SciTech Connect

    Juan D. Deaton; Lynda L. Brighton; Rangam Subramanian; Hussein Moradi; Jose Loera

    2013-09-01

    Spectrum sharing potentially holds the promise of solving the emerging spectrum crisis. However, technology innovators face the conundrum of developing spectrum sharing technologies without the ability to experiment and test with real incumbent systems. Interference with operational incumbents can prevent critical services, and the cost of deploying and operating an incumbent system can be prohibitive. Thus, the lack of incumbent systems and frequency authorization for technology incubation and demonstration has stymied spectrum sharing research. To this end, industry, academia, and regulators all require a test facility for validating hypotheses and demonstrating functionality without affecting operational incumbent systems. This article proposes a four-phase program supported by our spectrum accountability architecture. We propose that our comprehensive experimentation and testing approach for technology incubation and demonstration will accelerate the development of spectrum sharing technologies.

  8. Current limiting performance test of 3-phase tri-axial transformer-type SFCL with re-wound structure at 3-line-to-ground fault in lab-scale transmission system

    NASA Astrophysics Data System (ADS)

    Shirai, Yasuyuki; Noda, Sho; Yamabe, Kenta; Hattori, Keisuke; Baba, Jumpei; Kobayashi, Shinichi; Sato, Kenichi

    2013-01-01

    We have proposed a transformer-type SFCL of a re-wound structure, which can produce a limiting reactance (L-limiting) for smaller fault current and, for larger one, additively give a limiting resistance (L + R limiting). The single-phase proposed model SFCL had been tested and shown good limiting characteristics and excellent recovery performance. A 3-phase tri-axial SFCL of the proposed type had been designed and made using BSCCO2223. This paper describes demonstration tests of the model SFCL carried out using a lab-scale one-machine infinite bus transmission model system. The experimental results on the current limiting performance of the SFCL at the 3-line-to-ground (3LG) fault were shown and discussed. The peak fault current 560 A without SFCL was reduced to 230 A with SFCL immediately. The 3-phase SFCL successfully worked without large inter-phase interaction. The SFCL recovered to the stand-by mode under a typical Circuit Breaker (CB) operation sequence.

  9. On the Absorption Spectrum of Noble Gases at the Arc Spectrum Limit

    PubMed Central

    Fano, Ugo; Pupillo, Guido; Zannoni, Alberto; Clark, Charles W.

    2005-01-01

    Rydberg spectral lines of an atom are sometimes superimposed on the continuous spectrum of a different configuration. Effects of interaction among different configurations in one of these cases are theoretically investigated, and a formula is obtained that describes the behavior of absorption spectrum intensity. This offers qualitative justification of some experimental results obtained by BEUTLER in studies of absorption arc spectra of noble gases and Ib spectra of some metal vapors. PMID:27308180

  10. ALFA: Automated Line Fitting Algorithm

    NASA Astrophysics Data System (ADS)

    Wesson, R.

    2015-12-01

    ALFA fits emission line spectra of arbitrary wavelength coverage and resolution, fully automatically. It uses a catalog of lines which may be present to construct synthetic spectra, the parameters of which are then optimized by means of a genetic algorithm. Uncertainties are estimated using the noise structure of the residuals. An emission line spectrum containing several hundred lines can be fitted in a few seconds using a single processor of a typical contemporary desktop or laptop PC. Data cubes in FITS format can be analysed using multiple processors, and an analysis of tens of thousands of deep spectra obtained with instruments such as MUSE will take a few hours.

  11. The X-ray spectrum of Tycho

    NASA Technical Reports Server (NTRS)

    Hamilton, A. J. S.; Sarazin, C. L.; Szymkowiak, A. E.

    1986-01-01

    Baade (1945) has identified Tycho's supernova (SN) of A.D. 1572 as Type I, taking into account an analysis of the light curve recorded by Tycho. However, in spite of the obvious interest of Tycho's spectrum, to date the spectrum remains poorly understood. The present study is concerned with a reevaluation of the X-ray spectrum of Tycho. Attention is given to detailed nonequilibrium calculations and a self-consistent hydrodynamic model for ejecta consisting of pure heavy elements moving into a uniform external medium. The model provides a satisfactory fit to the spectrum, and avoids any requirement for a large mass of material in Tycho. It is demonstrated that the observed iron line emission is compatible with the presence of perhaps 0.7 solar mass of iron, of which 0.3 solar mass is shocked.

  12. High temperature bias line stabilized current sources

    DOEpatents

    Patterson, R.B. III.

    1984-09-11

    A compensation device for the base of emitter follower configured bipolar transistors becoming operable at elevated temperatures including a bipolar transistor of a geometry of not more than half the geometry of the bipolar emitter follower having its collector connected to the base of the emitter follower and its base and emitter connected together and to the emitter of the emitter follower. 1 fig.

  13. High temperature bias line stabilized current sources

    DOEpatents

    Patterson, III, Raymond B.

    1984-01-01

    A compensation device for the base of emitter follower configured bipolar transistors becoming operable at elevated temperatures including a bipolar transistor of a geometry of not more than half the geometry of the bipolar emitter follower having its collector connected to the base of the emitter follower and its base and emitter connected together and to the emitter of the emitter follower.

  14. Using iron line reverberation and spectroscopy to distinguish Kerr and non-Kerr black holes

    NASA Astrophysics Data System (ADS)

    Jiang, Jiachen; Bambi, Cosimo; Steiner, James F.

    2015-05-01

    The iron Kα line commonly observed in the X-ray spectrum of both stellar-mass and supermassive black hole candidates is produced by the illumination of a cold accretion disk by a hot corona. In this framework, the activation of a new flaring region in the hot corona imprints a time variation on the iron line spectrum. Future X-ray facilities with high time resolution and large effective areas may be able to measure the so-called 2-dimensional transfer function; that is, the iron line profile detected by a distant observer as a function of time in response to an instantaneous flare from the X-ray primary source. This work is a preliminary study to determine if and how such a technique can provide more information about the spacetime geometry around the compact object than the already possible measurements of the time-integrated iron line profile. Within our simplified model, we find that a measurement of iron line reverberation can improve constraints appreciably given a sufficiently strong signal, though that most of the information is present in the time-integrated spectrum. Our aim is to test the Kerr metric. We find that current X-ray facilities and data are unable to provide strong tests of the Kerr nature of supermassive black hole candidates. We consider an optimistic case of 105 iron line photons from a next-generation data set. With such data, the reverberation model improves upon the spectral constraint by an order of magnitude.

  15. Measure Lines

    ERIC Educational Resources Information Center

    Crissman, Sally

    2011-01-01

    One tool for enhancing students' work with data in the science classroom is the measure line. As a coteacher and curriculum developer for The Inquiry Project, the author has seen how measure lines--a number line in which the numbers refer to units of measure--help students not only represent data but also analyze it in ways that generate…

  16. Economic aspects of spectrum management

    NASA Technical Reports Server (NTRS)

    Stibolt, R. D.

    1979-01-01

    Problems associated with the allocation of the radio frequency spectrum are addressed. It is observed that the current method very likely does not allocate the resource to those most valuing its use. Ecomonic criteria by which the effectiveness of resource allocation schemes can be judged are set forth and some thoughts on traditional objections to implementation of market characteristics into frequency allocation are offered. The problem of dividing orbit and spectrum between two satellite services sharing the same band but having significantly different system characteristics is discussed. The problem is compounded by the likelihood that one service will commence operation much sooner than the other. Some alternative schemes are offered that, within proper international constraints, could achieve a desired flexibility in the division of orbit and frequency between the two services domestically over the next several years.

  17. Radiation detector spectrum simulator

    DOEpatents

    Wolf, Michael A.; Crowell, John M.

    1987-01-01

    A small battery operated nuclear spectrum simulator having a noise source nerates pulses with a Gaussian distribution of amplitudes. A switched dc bias circuit cooperating therewith generates several nominal amplitudes of such pulses and a spectral distribution of pulses that closely simulates the spectrum produced by a radiation source such as Americium 241.

  18. Radiation detector spectrum simulator

    DOEpatents

    Wolf, M.A.; Crowell, J.M.

    1985-04-09

    A small battery operated nuclear spectrum simulator having a noise source generates pulses with a Gaussian distribution of amplitudes. A switched dc bias circuit cooperating therewith to generate several nominal amplitudes of such pulses and a spectral distribution of pulses that closely simulates the spectrum produced by a radiation source such as Americium 241.

  19. The CMBR spectrum

    SciTech Connect

    Stebbins, A.

    1997-05-01

    Here we give an introduction to the observed spectrum of the Cosmic Microwave Background Radiation (CMBR) and discuss what can be learned about it. Particular attention will be given to how Compton scattering can distort the spectrum of the CMBR. An incomplete bibliography of relevant papers is also provided.

  20. Fission Spectrum Related Uncertainties

    SciTech Connect

    G. Aliberti; I. Kodeli; G. Palmiotti; M. Salvatores

    2007-10-01

    The paper presents a preliminary uncertainty analysis related to potential uncertainties on the fission spectrum data. Consistent results are shown for a reference fast reactor design configuration and for experimental thermal configurations. However the results obtained indicate the need for further analysis, in particular in terms of fission spectrum uncertainty data assessment.

  1. Fetal Alcohol Spectrum Disorder

    ERIC Educational Resources Information Center

    Caley, Linda M.; Kramer, Charlotte; Robinson, Luther K.

    2005-01-01

    Fetal alcohol spectrum disorder (FASD) is a serious and widespread problem in this country. Positioned within the community with links to children, families, and healthcare systems, school nurses are a critical element in the prevention and treatment of those affected by fetal alcohol spectrum disorder. Although most school nurses are familiar…

  2. Recombination line intensities for hydrogenic ions. III - Effects of finite optical depth and dust

    NASA Technical Reports Server (NTRS)

    Hummer, D. G.; Storey, P. J.

    1992-01-01

    The effect on the recombination spectrum of hydrogen arising from: (1) finite optical thickness in the Lyman lines; (2) the overlapping of Lyman lines near the series limit; (3) the absorption of Lyman lines by dust or photoionization, and (4) the long-wave radiation emitted by dust is examined. Full account is taken of electron and heavy particle collisions in redistributing energy and angular momentum. It is seen that each of these deviations from the classical Case B leads to observable effects, and that dust influences the recombination spectrum in characteristic ways that may make possible new observational constraints on dust properties in nebulosities. On the basis of these calculations it is believed that the uncertainty in the determination of the helium-to-hydrogen abundance ratio in the universe may be larger than currently claimed.

  3. Design and performance of a variable spectrum synthesizer

    NASA Astrophysics Data System (ADS)

    Huebschman, M. L.; Hunt, J.; Munjuluri, B.; Takashima, A.; Garner, H. R.

    2004-11-01

    We present the design and performance of a broadband variable spectrum synthesizer (VSS). The VSS system is capable of synthesizing multiple arbitrary spectra using an arc lamp as a source, a spectrograph to disperse the light, a digital micromirror device to select wavelengths and adjust intensities, and optical components to focus and direct the light. The VSS can provide radiation with a spectrum of selected wavelengths dispersed over an area or recombined into a narrow line. The area mode is most useful when imaging the spectrum across a target area is desired. The wavelength dispersion in this mode provides a spatially modulated spectral profile for comparing responses to the wavelengths in the selected bands. The line mode has utility in cases where a light signal with many superimposed spectra is desired. Both modes can simulate the spectra with a very specific wavelength, intensity, and exposure time characteristic. The current VSS system provides intensity and wavelength variations over a range from 250 to 1100 nm and can level wavelength intensities variations to within 15%. The instrument wavelength resolution was measured as 2.0 nm±0.5 nm and the maximum power density delivered was 220 μW/cm2 nm (365 nm). Although the VSS has applications in a number of physics and engineering disciplines, the control software and application described are tailored for measurement of wavelength-induced apoptosis/necrosis of skin cancer cells in the field of clinical phototherapy. An experiment using psoralens coupled with UVA light and an experiment using visible light in photodynamic therapy are discussed. The experimental results obtained for radiation of wavelengths between 300 and 700 nm at various exposures on living cells are presented.

  4. UAS CNPC Satellite Link Performance - Sharing Spectrum with Terrestrial Systems

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Wilson, Jeffrey D.; Bishop, William D.

    2016-01-01

    In order to provide for the safe integration of unmanned aircraft systems into the National Airspace System, the control and non-payload communications (CNPC) link connecting the ground-based pilot with the unmanned aircraft must be highly reliable. A specific requirement is that it must operate using aviation safety radiofrequency spectrum. The 2012 World Radiocommunication Conference (WRC-12) provided a potentially suitable allocation for radio line-of-sight (LOS), terrestrial based CNPC link at 5030-5091 MHz. For a beyond radio line-of-sight (BLOS), satellite-based CNPC link, aviation safety spectrum allocations are currently inadequate. Therefore, the 2015 WRC will consider the use of Fixed Satellite Service (FSS) bands to provide BLOS CNPC under Agenda Item 1.5. This agenda item requires studies to be conducted to allow for the consideration of how unmanned aircraft can employ FSS for BLOS CNPC while maintaining existing systems. Since there are terrestrial Fixed Service systems also using the same frequency bands under consideration in Agenda Item 1.5 one of the studies required considered spectrum sharing between earth stations on-board unmanned aircraft and Fixed Service station receivers. Studies carried out by NASA have concluded that such sharing is possible under parameters previously established by the International Telecommunications Union. As the preparation for WRC-15 has progressed, additional study parameters Agenda Item 1.5 have been proposed, and some studies using these parameters have been added. This paper examines the study results for the original parameters as well as results considering some of the more recently proposed parameters to provide insight into the complicated process of resolving WRC-15 Agenda Item 1.5 and achieving a solution for BLOS CNPC for unmanned aircraft.

  5. Adjustable direct current and pulsed circuit fault current limiter

    DOEpatents

    Boenig, Heinrich J.; Schillig, Josef B.

    2003-09-23

    A fault current limiting system for direct current circuits and for pulsed power circuit. In the circuits, a current source biases a diode that is in series with the circuits' transmission line. If fault current in a circuit exceeds current from the current source biasing the diode open, the diode will cease conducting and route the fault current through the current source and an inductor. This limits the rate of rise and the peak value of the fault current.

  6. Consecutive combined response spectrum

    NASA Astrophysics Data System (ADS)

    Xu, Longjun; Zhao, Guochen; Liu, Qingyang; Xie, Yujian; Xie, Lili

    2014-12-01

    Appropriate estimates of earthquake response spectrum are essential for design of new structures, or seismic safety evaluation of existing structures. This paper presents an alternative procedure to construct design spectrum from a combined normalized response spectrum (NRSC) which is obtained from pseudo-velocity spectrum with the ordinate scaled by different peak ground amplitudes (PGA, PGV, PGD) in different period regions. And a consecutive function f( T) used to normalize the ordinates is defined. Based on a comprehensive study of 220 strong ground motions recorded during recent eleven large worldwide earthquakes, the features of the NRSC are discussed and compared with the traditional normalized acceleration, velocity and displacement response spectra (NRSA, NRSV, NRSD). And the relationships between ground amplitudes are evaluated by using a weighted mean method instead of the arithmetic mean. Then the NRSC is used to define the design spectrum with given peak ground amplitudes. At last, the smooth spectrum is compared with those derived by the former approaches, and the accuracy of the proposed spectrum is tested through an analysis of the dispersion of ground motion response spectra.

  7. On the emitting region of X-ray fluorescent lines around Compton-thick AGN

    NASA Astrophysics Data System (ADS)

    Liu, Jiren

    2016-06-01

    X-ray fluorescent lines are unique features of the reflection spectrum of the torus when irradiated by the central active galactic nuclei (AGN). Their intrinsic line width can be used to probe the line-emitting region. Previous studies have focused on the Fe K α line at 6.4 keV, which is the most prominent fluorescent line. These studies, however, are limited by the spectral resolution of currently available instruments, the best of which is ˜1860 km s-1 afforded by the Chandra High-Energy Grating (HEG). The HEG spectral resolution is improved by a factor of 4 at 1.74 keV, where the Si K α line is located. We measured the full width at half-maximum of the Si K α line for Circinus, Mrk 3, and NGC 1068, which are 570 ± 240, 730 ± 320, and 320 ± 280 km s-1, respectively. They are 3-5 times smaller than those measured with the Fe K α line previously. It shows that the intrinsic widths of the Fe K α line are most likely to be overestimated. The measured widths of the Si K α line put the line-emitting region outside the dust sublimation radius in these galaxies. It indicates that for Compton-thick AGN, the X-ray fluorescence material are likely to be the same as the dusty torus emitting in the infrared band.

  8. Frequency Spectrum for Integration of Unmanned Aircraft

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Wilson, Jeffrey D.; Bishop, William D.

    2013-01-01

    The goal of enabling the integration of unmanned aircraft systems (UAS) into the National Airspace System (NAS) in terms of UAS achieving routine access to the NAS has been established as a national goal in the United States. Among a number of technical barriers that must be overcome to meet this goal is the absence of standard, certifiable communications links supplying the control and non-payload communications (CNPC) function, essentially providing the link over which a pilot on the ground can control the unmanned aircraft (UA). The International Civil Aviation Organization (ICAO) has determined that the CNPC link must operate over protected aviation spectrum. Therefore protected aviation spectrum must be allocated for this function, approved through the processes of the International Telecommunications Union Radiocommunication Sector (ITU-R). Work has progressed in the definition of spectrum requirements for CNPC, and a portion of these requirements has been satisfied through new allocations approved at the ITU-R 2012 World Radiocommunication Conference (WRC-12). Additional work is ongoing or planned to satisfy the remaining spectrum requirements and define the specifications for the usage of CNPC spectrum allocations and develop supporting standards. This paper provides an overview of the status of RF spectrum for UAS CNPC. Issues that have been identified and ongoing analysis and research that will be necessary to fulfill spectrum requirements for UAS CNPC will be discussed. The results of this work will provide for the safe integration of UA into the NAS in both the LOS (Line of Sight) and BLOS (Beyond Line of Sight) realms.

  9. Shuttle spectrum despreader

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The results of the spread spectrum despreader project are reported and three principal products are designed and tested. The products are, (1) a spread spectrum despreader breadboard, (2) associated test equipment consisting of a spectrum spreader and bit reconstruction/error counter and (3) paper design of a Ku-band receiver which would incorporate the despreader as a principal subsystem. The despreader and test set are designed for maximum flexibility. A choice of unbalanced quadriphase or biphase shift keyed data modulation is available. Selectable integration time and threshold voltages on the despreader further lend true usefulness as laboratory test equipment to the delivered hardware.

  10. Synthetic CA II Triplet Lines

    NASA Astrophysics Data System (ADS)

    Erdelyi, M. M.; Barbuy, B.

    1990-11-01

    RESUMEN. Se hicieron calculos de sintesis del espectro en el ititervalo de longitud de onda - 8700 A, ara ? oder verificar el comporta- mien to de diferentes lineas moleculares y at5micas como funci5n de los parametros esteldres de temperatura, gravedad y metalicidad. El espec- tro sintetico ha sido generado para:(a) todas las , (b) solamente de CN, (c) solamente de TiO, y (d) solamente lineas at6micas. Abstract. Spectrum synthesis calculations are carried out in the wavelength interval X 8300 - 8700 A, in order to verify the behaviour of different molecular and atomic lines as a function of the stellar para meters temperature, gravity and metallicity. Synthetic spectra were ge nerated for: (a) all lines, (b) only CN lines, (c) only TiO lines, and (d) only atomic lines Key `td6: LINE-PROFILE - ST S-AThOSPHERES

  11. On systematic errors in spectral line parameters retrieved with the Voigt line profile

    NASA Astrophysics Data System (ADS)

    Kochanov, V. P.

    2012-08-01

    Systematic errors inherent in the Voigt line profile are analyzed. Molecular spectrum processing with the Voigt profile is shown to underestimate line intensities by 1-4%, with the errors in line positions being 0.0005 cm-1 and the decrease in pressure broadening coefficients varying from 5% to 55%.

  12. DISCOVERY OF THE TRANSITION OF A MINI-BROAD ABSORPTION LINE INTO A BROAD ABSORPTION LINE IN THE SDSS QUASAR J115122.14+020426.3

    SciTech Connect

    Hidalgo, Paola Rodriguez; Eracleous, Michael; Charlton, Jane; Hamann, Fred; Murphy, Michael T.; Nestor, Daniel

    2013-09-20

    We present the detection of a rare case of dramatic strengthening in the UV absorption profiles in the spectrum of the quasar J115122.14+020426.3 between observations {approx}2.86 yr apart in the quasar rest frame. A spectrum obtained in 2001 by the Sloan Digital Sky Survey shows a C IV ''mini-broad'' absorption line (FWHM = 1220 km s{sup -1}) with a maximum blueshift velocity of {approx}9520 km s{sup -1}, while a later spectrum from the Very Large Telescope shows a significantly broader and stronger absorption line, with a maximum blueshift velocity of {approx}12, 240 km s{sup -1} that qualifies as a broad absorption line. A similar variability pattern is observed in two additional systems at lower blueshifted velocities and in the Ly{alpha} and N V transitions as well. One of the absorption systems appears to be resolved and shows evidence for partial covering of the quasar continuum source (C{sub f} {approx} 0.65), indicating a transverse absorber size of, at least, {approx}6 Multiplication-Sign 10{sup 16} cm. In contrast, a cluster of narrower C IV lines appears to originate in gas that fully covers the continuum and broad emission line sources. There is no evidence for changes in the centroid velocity of the absorption troughs. This case suggests that at least some of the absorbers that produce ''mini-broad'' and broad absorption lines in quasar spectra do not belong to intrinsically separate classes. Here, the ''mini-broad'' absorption line is most likely interpreted as an intermediate phase before the appearance of a broad absorption line due to their similar velocities. While the current observations do not provide enough constraints to discern among the possible causes for this variability, future monitoring of multiple transitions at high resolution will help achieve this goal.

  13. IONIZED OUTFLOWS FROM COMPACT STEEP SPECTRUM SOURCES

    SciTech Connect

    Shih, Hsin-Yi; Stockton, Alan; Kewley, Lisa E-mail: stockton@ifa.hawaii.edu

    2013-08-01

    Massive outflows are known to exist, in the form of extended emission-line regions (EELRs), around about one-third of powerful FR II radio sources. We investigate the origin of these EELRs by studying the emission-line regions around compact-steep-spectrum (CSS) radio galaxies that are younger (10{sup 3}-10{sup 5} yr old) versions of the FR II radio galaxies. We have searched for and analyzed the emission-line regions around 11 CSS sources by taking integral field spectra using Gemini Multi-Object Spectrograph on Gemini North. We fit the [O III] {lambda}5007 line and present the velocity maps for each detected emission-line region. We find, in most cases, that the emission-line regions have multi-component velocity structures with different velocity dispersions and/or flux distributions for each component. The velocity gradients of the emission-line gas are mostly well aligned with the radio axis, suggesting a direct causal link between the outflowing gas and the radio jets. The complex velocity structure may be a result of different driving mechanisms related to the onset of the radio jets. We also present the results from the line-ratio diagnostics we used to analyze the ionization mechanism of the extended gas, which supports the scenario where the emission-line regions are ionized by a combination of active galactic nucleus radiation and shock excitation.

  14. Fetal Alcohol Spectrum Disorders

    MedlinePlus

    ... alcohol can cause a group of conditions called fetal alcohol spectrum disorders (FASDs). Effects can include physical and behavioral problems such ... alcohol syndrome is the most serious type of FASD. People with fetal alcohol syndrome have facial abnormalities, ...

  15. Quantum Spread Spectrum Communication

    SciTech Connect

    Humble, Travis S

    2010-01-01

    We demonstrate that spectral teleportation can coherently dilate the spectral probability amplitude of a single photon. In preserving the encoded quantum information, this variant of teleportation subsequently enables a form of quantum spread spectrum communication.

  16. Basic Modeling of the Solar Atmosphere and Spectrum

    NASA Technical Reports Server (NTRS)

    Avrett, Eugene; Wagner, William J. (Technical Monitor)

    2003-01-01

    This grant supported the research and publication of a major 26-page paper in The Astrophysical Journal, by Fontenla, Avrett, & Loeser (2002): 'Energy Balance in the Solar Transition Region. IV. Hydrogen and Helium Mass Flows with Diffusion.' This paper extended our previous modeling of the chromosphere-corona transition region to include cases with particle and mass flows. Inflows and outflows were shown to produce striking changes in the profiles of hydrogen and helium lines. An important conclusion is that line shifts are much less significant than the changes in line intensity and central reversal due to the influence of flows on the excitation and ionization of atoms in the solar atmosphere. This modeling effort at SAO is the only current one being undertaken anywhere to simulate in detail the full range of non-LTE absorption, emission, and scattering processes in the solar atmosphere to account for the entire solar spectrum from radio waves to X-rays. This effort is being continued with internal SAO funding at a relatively slow pace. Further NASA support in the future would yield results of great value for the interpretation of solar observations from NASA spacecraft.

  17. Harrison-Zel'dovich primordial spectrum is consistent with observations

    SciTech Connect

    Pandolfi, Stefania; Cooray, Asantha; Serra, Paolo; Giusarma, Elena; Mena, Olga; Kolb, Edward W.; Melchiorri, Alessandro

    2010-06-15

    Inflation predicts primordial scalar perturbations with a nearly scale-invariant spectrum and a spectral index approximately unity [the Harrison-Zel'dovich (HZ) spectrum]. The first important step for inflationary cosmology is to check the consistency of the HZ primordial spectrum with current observations. Recent analyses have claimed that a HZ primordial spectrum is excluded at more than 99% c.l. Here we show that the HZ spectrum is only marginally disfavored if one considers a more general reionization scenario. Data from the Planck mission will settle the issue.

  18. Langley's mapping of the infra-red solar spectrum

    NASA Astrophysics Data System (ADS)

    Loettgers, Andrea

    In 1900 Samuel P. Langley published the outcome of 20 years of investigation: a line spectrum of the infra-red solar spectrum. Although this map resembled Henry A. Rowland's map of the visible part of the spectrum, which had been produced by recording it directly on a photographic plate, Langley proceeded quite differently. Because infrared-sensitive emulsions weren't available, Langley devised a new instrument for measuring radiation, the bolometer. Its functioning was based on the proportional variation of the resistance of metals with temperature. The variations were automatically recorded on a photographic plate and led to an intensity curve called bolograph. This bolograph was then photographically transformed into a line spectrum. The main questions which I will discuss in connection with this representation: What did it represent after all these transformations? Did all the dark lines correspond to absorption lines in the as yet unexplored infra-red spectrum? Did some correspond to disturbances coming from the instruments or from external disturbances such as variations in the temperature of the environment? How could they be isolated? Connected questions are: Did Langley try to conform a shared standard by using automatic recording devices in his measurements? Was the last transformation into line spectrum an adaptation to Rowland`s map, considered a standard at this time, so that the infra-red map provided a continuation of this map?

  19. High efficiency laser spectrum conditioner

    DOEpatents

    Greiner, Norman R.

    1980-01-01

    A high efficiency laser spectrum conditioner for generating a collinear parallel output beam containing a predetermined set of frequencies from a multifrequency laser. A diffraction grating and spherical mirror are used in combination, to disperse the various frequencies of the input laser beam and direct these frequencies along various parallel lines spatially separated from one another to an apertured mask. Selection of the desired frequencies is accomplished by placement of apertures at locations on the mask where the desired frequencies intersect the mask. A recollimated parallel output beam with the desired set of frequencies is subsequently generated utilizing a mirror and grating matched and geometrically aligned in the same manner as the input grating and mirror.

  20. Decision Analysis of Dynamic Spectrum Access Rules

    SciTech Connect

    Juan D. Deaton; Luiz A. DaSilva; Christian Wernz

    2011-12-01

    A current trend in spectrum regulation is to incorporate spectrum sharing through the design of spectrum access rules that support Dynamic Spectrum Access (DSA). This paper develops a decision-theoretic framework for regulators to assess the impacts of different decision rules on both primary and secondary operators. We analyze access rules based on sensing and exclusion areas, which in practice can be enforced through geolocation databases. Our results show that receiver-only sensing provides insufficient protection for primary and co-existing secondary users and overall low social welfare. On the other hand, using sensing information between the transmitter and receiver of a communication link, provides dramatic increases in system performance. The performance of using these link end points is relatively close to that of using many cooperative sensing nodes associated to the same access point and large link exclusion areas. These results are useful to regulators and network developers in understanding in developing rules for future DSA regulation.

  1. The Ultraviolet Spectrum of the Jovian Dayglow

    NASA Technical Reports Server (NTRS)

    Liu, Weihong; Dalgarno, A.

    1995-01-01

    The ultraviolet spectra of molecular hydrogen H2 and HD due to solar fluorescence and photoelectron excitation are calculated and compared with the Jovian equatorial dayglow spectrum measured at 3 A resolution at solar maximum. The dayglow emission is accounted for in both brightness and spectral shape by the solar fluorescence and photoelectron excitation and requires no additional energy source. The emission is characterized by an atmospheric temperature of 530 K and an H2 column density of 10(exp 20) cm(exp -2). The dayglow spectrum contains a cascade contribution to the Lyman band emission from high-lying E and F states. Its relative weakness at short wavelengths is due to both self-absorption by H2 and absorption by CH4. Strong wavelength coincidences of solar emission lines and absorption lines of H2 and HD produce unique line spectra which can be identified in the dayglow spectrum. The strongest fluorescence is due to absorption of the solar Lyman-beta line at 1025.72 A by the P(1) line of the (6, 0) Lyman band of H2 at 1025.93 A. The fluorescence lines due to absorption of the solar O 6 line at 1031.91 A by vibrationally excited H2 via the Q(3) line of the (1, 1) Werner band at 1031.86 A are identified. The fluorescence lines provide a sensitive measure of the atmospheric temperature. There occurs an exact coincidence of the solar O 6 line at 1031.91 A and the R(0) line of the (6, 0) Lyman band of HD at 1031-91 A, but HD on Jupiter is difficult to detect due to the dominance of the H2 emission where the HD emission is particularly strong. Higher spectral resolution and higher sensitivity may make possible such a detection. The high resolution (0.3 A) spectra of H2 and HD are presented to stimulate search for the HD on Jupiter with the Hubble Space Telescope.

  2. Palbociclib as a first-line treatment in oestrogen receptor-positive, HER2-negative, advanced breast cancer not cost-effective with current pricing: a health economic analysis of the Swiss Group for Clinical Cancer Research (SAKK).

    PubMed

    Matter-Walstra, K; Ruhstaller, T; Klingbiel, D; Schwenkglenks, M; Dedes, K J

    2016-07-01

    Endocrine therapy continues to be the optimal systemic treatment for metastatic ER(+)HER2(-) breast cancer. The CDK4/6 inhibitor palbociclib combined with letrozole has recently been shown to significantly improve progression-free survival. Here we examined the cost-effectiveness of this regimen for the Swiss healthcare system. A Markov cohort simulation based on the PALOMA-1 trial (Finn et al. in Lancet Oncol 16:25-35, 2015) was used as the clinical course. Input parameters were based on summary trial data. Costs were assessed from the Swiss healthcare system perspective. Adding palbociclib to letrozole (PALLET) compared to letrozole monotherapy was estimated to cost an additional CHF342,440 and gain 1.14 quality-adjusted life years, resulting in an incremental cost-effectiveness ratio (ICER) of CHF301,227/QALY gained. In univariate sensitivity analyses, no tested variation in key parameters resulted in an ICER below a willingness-to-pay threshold of CHF100,000/QALY. PALLET had a 0 % probability of being cost-effective in probabilistic sensitivity analyses. Lowering PALLET's price by 75 % resulted in an ICER of CHF73,995/QALY and a 73 % probability of being cost-effective. At current prices, PALLET would cost the Swiss healthcare system an additional CHF155 million/year. Palbociclib plus letrozole cannot be considered cost-effective for the first-line treatment of patients with metastatic breast cancer in the Swiss healthcare system. PMID:27277747

  3. Optical spectrum variations of IL Cep A

    NASA Astrophysics Data System (ADS)

    Ismailov, N. Z.; Khalilov, O. V.; Bakhaddinova, G. R.

    2016-02-01

    The results of many-year uniform spectroscopic observations of the Herbig Ae/Be star IL Cep A are presented. Its Hα line has either a single or a barely resolved two-component emission profile. The H β emission line is clearly divided into two components with a deep central absorption. Smooth variations of the observed parameters of individual spectral lines over nine years are observed. The He I λ5876 Å line has a complex absorption profile, probably with superposed emission components. The NaI D1, D2 doublet exhibits weak changes due to variations in the circumstellar envelope. The variations observed in the stellar spectrum can be explained by either binarity or variations of the magnetic field in the stellar disk. Difficulties associated with both these possibilities are discussed.

  4. The ultraviolet spectrum of Beta Lyrae

    NASA Technical Reports Server (NTRS)

    Mazzali, Paolo A.

    1987-01-01

    The high-resolution UV spectrum of Beta Lyrae observed with the IUE satellite between 1980 and 1986 is analyzed. A complete list of line identifications for the entire spectral range of the IUE (1225-3125 A) is presented. The main spectral features are P Cygni profiles of resonance lines of high ionization states typical of stellar winds, some of which are combined with a broad emission feature due probably to an accretion disk; P Cygni profiles due to moderately ionized atoms in the iron group (mostly Fe III and Ni III); and absorption lines of elements in lower ionization stages, such as S II, Si II (higher multiplets), Ni II, and a large number of Fe II lines.

  5. LANSCE beam current limiter

    SciTech Connect

    Gallegos, F.R.

    1996-06-01

    The Radiation Security System (RSS) at the Los Alamos Neutron Science Center (LANSCE) provides personnel protection from prompt radiation due to accelerated beam. Active instrumentation, such as the Beam Current Limiter, is a component of the RSS. The current limiter is designed to limit the average current in a beam line below a specific level, thus minimizing the maximum current available for a beam spill accident. The beam current limiter is a self-contained, electrically isolated toroidal beam transformer which continuously monitors beam current. It is designed as fail-safe instrumentation. The design philosophy, hardware design, operation, and limitations of the device are described.

  6. Action spectrum for photocarcinogenesis.

    PubMed

    de Gruijl, F R

    1995-01-01

    The wavelength dependence of the carcinogenicity of ultraviolet (UV) radiation needs to be known in order to assess the carcinogenic risks of various UV sources, most notably the different solar UV spectra at ground level under depleting stratospheric ozone. This wavelength dependence cannot be extracted from human data (e.g., from epidemiology); it can, however, be directly obtained from animal experiments. Precise information on the wavelength dependence, the so-called action spectrum, was not available until recently: erythemal or mutagenic action spectra have been used as substitutes. However, experimental data on skin tumors induced in hairless mice (Skh:HR1) with various polychromatic sources have been building up. Our group has found that none of the substitute action spectra yield a statistically acceptable description of our data, and we have, therefore, derived a new action spectrum, dubbed the SCUP action spectrum (SCUP stands for Skin Cancer Utrecht-Philadelphia, because the action spectrum also fits experimental data from the former Skin and Cancer Hospital in Philadelphia). The SCUP action spectrum has a maximum at 293 nm, and in the UVA region above 340 nm the relative carcinogenicity per J/m2 drops to about 10(-4) of this maximum. The effects of an ozone depletion on solar UV doses weighted with these different action spectra are compared: the erythemal and SCUP weighted dose come out as least sensitive with a 1.3% and 1.4% increase, respectively, for every 1% decrease in ozone. PMID:7597292

  7. Cloudy 94 and Applications to Quasar Emission Line Regions

    NASA Technical Reports Server (NTRS)

    Ferland, Gary J.

    2000-01-01

    This review discusses the most recent developments of the plasma simulation code Cloudy and its application to the, emission-line regions of quasars. The longterm goal is to develop the tools needed to determine the chemical composition of the emitting gas and the luminosity of the central engine for any emission line source. Emission lines and the underlying thermal continuum are formed in plasmas that are far from thermodynamic equilibrium. Their thermal and ionization states are the result of a balance of a vast set of microphysical processes. Once produced, radiation must, propagate out of the (usually) optically thick source. No analytic solutions are possible, and recourse to numerical simulations is necessary. I am developing the large-scale plasma simulation code Cloudy as an investigative tool for this work, much as an observer might build a spectrometer. This review describes the current version of Cloudy, version 94. It describes improvements made since the, release of the previous version, C90. The major recent, application has been the development of the "Locally Optimally-Emitting Cloud" (LOC) model of AGN emission line regions. Powerful selection effects, introduced by the atomic physics and line formation process, permit individual lines to form most efficiently only near certain selected parameters. These selection effects, together with the presence of gas with a wide range of conditions, are enough to reproduce the spectrum of a typical quasar with little dependence on details. The spectrum actually carries little information to the identity of the emitters. I view this as a major step forward since it provides a method to handle accidental details at the source, so that we can concentrate on essential information such as the luminosity or chemical composition of the quasar.

  8. Broad spectrum solar cell

    DOEpatents

    Walukiewicz, Wladyslaw; Yu, Kin Man; Wu, Junqiao; Schaff, William J.

    2007-05-15

    An alloy having a large band gap range is used in a multijunction solar cell to enhance utilization of the solar energy spectrum. In one embodiment, the alloy is In.sub.1-xGa.sub.xN having an energy bandgap range of approximately 0.7 eV to 3.4 eV, providing a good match to the solar energy spectrum. Multiple junctions having different bandgaps are stacked to form a solar cell. Each junction may have different bandgaps (realized by varying the alloy composition), and therefore be responsive to different parts of the spectrum. The junctions are stacked in such a manner that some bands of light pass through upper junctions to lower junctions that are responsive to such bands.

  9. NREL Spectrum of Innovation

    ScienceCinema

    None

    2013-05-29

    There are many voices calling for a future of abundant clean energy. The choices are difficult and the challenges daunting. How will we get there? The National Renewable Energy Laboratory integrates the entire spectrum of innovation including fundamental science, market relevant research, systems integration, testing and validation, commercialization and deployment. The innovation process at NREL is interdependent and iterative. Many scientific breakthroughs begin in our own laboratories, but new ideas and technologies come to NREL at any point along the innovation spectrum to be validated and refined for commercial use.

  10. Bottomonium spectrum revisited

    NASA Astrophysics Data System (ADS)

    Segovia, Jorge; Ortega, Pablo G.; Entem, David R.; Fernández, Francisco

    2016-04-01

    We revisit the bottomonium spectrum motivated by the recently exciting experimental progress in the observation of new bottomonium states, both conventional and unconventional. Our framework is a nonrelativistic constituent quark model which has been applied to a wide range of hadronic observables from the light to the heavy quark sector, and thus the model parameters are completely constrained. Beyond the spectrum, we provide a large number of electromagnetic, strong and hadronic decays in order to discuss the quark content of the bottomonium states and give more insights about a better way to determine their properties experimentally.

  11. School Nurses' Knowledge of Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Strunk, Julie A.

    2009-01-01

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

  12. Auditory Neuropathy Spectrum Disorder: A Review

    ERIC Educational Resources Information Center

    Norrix, Linda W.; Velenovsky, David S.

    2014-01-01

    Purpose: Auditory neuropathy spectrum disorder, or ANSD, can be a confusing diagnosis to physicians, clinicians, those diagnosed, and parents of children diagnosed with the condition. The purpose of this review is to provide the reader with an understanding of the disorder, the limitations in current tools to determine site(s) of lesion, and…

  13. The Double-lined Spectrum of LBV 1806-20

    NASA Astrophysics Data System (ADS)

    Figer, Donald F.; Najarro, Francisco; Kudritzki, Rolf P.

    2004-08-01

    Despite much theoretical and observational progress, there is no known firm upper limit to the masses of stars. Our understanding of the interplay between the immense radiation pressure produced by massive stars in formation and the opacity of infalling material is subject to theoretical uncertainties, and many observational claims of ``the most massive star'' have failed the singularity test. LBV 1806-20 is a particularly luminous object, L~106 Lsolar, for which some have claimed very high mass estimates (Minitial>200 Msolar), based in part on its similarity to the Pistol star. We present high-resolution near-infrared spectroscopy of LBV 1806-20, showing that it is possibly a binary system with components separated in velocity by ~70 km s-1. If correct, then this system is not the most massive star known, yet it is a massive binary system. We argue that a binary, or merged, system is more consistent with the ages of nearby stars in the LBV 1806-20 cluster. In addition, we find that the velocity of VLSR=36 km s-1 is consistent with a distance of 11.8 kpc, a luminosity of 106.3 Lsolar, and a system mass of ~130 Msolar. Data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The observatory was made possible by the generous financial support of the W. M. Keck Foundation.

  14. Spectrum formation in superluminous supernovae (Type I)

    NASA Astrophysics Data System (ADS)

    Mazzali, P. A.; Sullivan, M.; Pian, E.; Greiner, J.; Kann, D. A.

    2016-06-01

    The near-maximum spectra of most superluminous supernovae (SLSNe) that are not dominated by interaction with a H-rich circum-stellar medium (SLSN-I) are characterized by a blue spectral peak and a series of absorption lines which have been identified as O II. SN 2011kl, associated with the ultra-long gamma-ray burst GRB111209A, also had a blue peak but a featureless optical/ultraviolet (UV) spectrum. Radiation transport methods are used to show that the spectra (not including SN 2007bi, which has a redder spectrum at peak, like ordinary SNe Ic) can be explained by a rather steep density distribution of the ejecta, whose composition appears to be typical of carbon-oxygen cores of massive stars which can have low metal content. If the photospheric velocity is ˜10 000-15 000 km s-1, several lines form in the UV. O II lines, however, arise from very highly excited lower levels, which require significant departures from local thermodynamic equilibrium to be populated. These SLSNe are not thought to be powered primarily by 56Ni decay. An appealing scenario is that they are energized by X-rays from the shock driven by a magnetar wind into the SN ejecta. The apparent lack of evolution of line velocity with time that characterizes SLSNe up to about maximum is another argument in favour of the magnetar scenario. The smooth UV continuum of SN 2011kl requires higher ejecta velocities (˜20 000 km s-1): line blanketing leads to an almost featureless spectrum. Helium is observed in some SLSNe after maximum. The high-ionization near-maximum implies that both He and H may be present but not observed at early times. The spectroscopic classification of SLSNe should probably reflect that of SNe Ib/c. Extensive time coverage is required for an accurate classification.

  15. The communications spectrum: Frequency allocations and auctions

    NASA Astrophysics Data System (ADS)

    Pritchard, Wilbur

    1997-01-01

    Demands on the communications spectrum have increased sharply because of the growth in radio communication services, the large bandwidths now required, and the rapid increases in world population. The problem will be exacerbated by the requirements of high definition television and the enormous amounts of information that will be transmitted by radio. The electromagnetic spectrum is a finite natural resource of great value used for emergency communications and military operations as well as for commercial purposes. Both government and the marketplace have proper roles in the allocation of its resources. There are no viable alternatives to international organizations such as the International Telecommunication Union or to agencies such as the Federal Communications Commission for the regulation of radio communication and the assignment of spectrum to essential public services. Although government auctions of spectrum are justifiable where there is no way to distinguish among commercial entities seeking to use the same bands for similar services, the practice is inherently inequitable and discourages development of new uses for the spectrum by removing investment protection. Recommended alternatives to auctions are: (1) lotteries, which keep assets and proceeds in the economy; and (2) ongoing charges for current as well as new users of the spectrum.

  16. The Frequency Spectrum Radio.

    ERIC Educational Resources Information Center

    Howkins, John, Ed.

    1979-01-01

    This journal issue focuses on the frequency spectrum used in radio communication and on the World Administrative Radio Conference, sponsored by the International Telecommunication Union, held in Geneva, Switzerland, in the fall of 1979. Articles describe the World Administrative Radio Conference as the most important radio communication conference…

  17. Charging for Spectrum Use.

    ERIC Educational Resources Information Center

    Geller, Henry; Lampert, Donna

    This paper, the third in a series exploring future options for public policy in the communications and information arenas, argues that the communications spectrum--e.g., public mobile service, private radio, and domestic satellites--is a valuable but limited resource that should benefit all Americans. After a background discussion, it is…

  18. Sinclair ZX Spectrum.

    ERIC Educational Resources Information Center

    Rodwell, Peter

    1982-01-01

    Describes and evaluates the hardware, software, peripheral devices, performance capabilities, and programing capacity of the Sinclair ZX Spectrum microcomputer. The computer's display system, its version of the BASIC programing language, its graphics capabilities, and the unique features of its data entry keyboard are discussed. (JL)

  19. The presence of Si I series in the ultraviolet solar spectrum - 3000 to 1200 A

    NASA Technical Reports Server (NTRS)

    Moore, C. E.; Brown, C. M.; Sandlin, G. D.; Tilford, S. G.; Tousey, R.

    1977-01-01

    Laboratory and solar data are presented which form the basis for identifying chromospheric Si I absorption lines in UV rocket spectra of the solar limb. Prints of the Si I laboratory spectrum between 1520 and 1570 A are matched with those of the chromospheric spectrum, and a striking line-to-line coincidence is observed. Individual absorption series of Si I covering the 3p(2), 3P, 1D, and 1S ground terms are tabulated in multiplet form over the wavelength range from 1517 to 3069 A. It is noted that many of the solar lines are blended with both other Si I lines and lines of other spectra.

  20. Broad-Spectrum Antiviral Therapeutics

    PubMed Central

    Rider, Todd H.; Zook, Christina E.; Boettcher, Tara L.; Wick, Scott T.; Pancoast, Jennifer S.; Zusman, Benjamin D.

    2011-01-01

    Currently there are relatively few antiviral therapeutics, and most which do exist are highly pathogen-specific or have other disadvantages. We have developed a new broad-spectrum antiviral approach, dubbed Double-stranded RNA (dsRNA) Activated Caspase Oligomerizer (DRACO) that selectively induces apoptosis in cells containing viral dsRNA, rapidly killing infected cells without harming uninfected cells. We have created DRACOs and shown that they are nontoxic in 11 mammalian cell types and effective against 15 different viruses, including dengue flavivirus, Amapari and Tacaribe arenaviruses, Guama bunyavirus, and H1N1 influenza. We have also demonstrated that DRACOs can rescue mice challenged with H1N1 influenza. DRACOs have the potential to be effective therapeutics or prophylactics for numerous clinical and priority viruses, due to the broad-spectrum sensitivity of the dsRNA detection domain, the potent activity of the apoptosis induction domain, and the novel direct linkage between the two which viruses have never encountered. PMID:21818340

  1. Prevalence of Autism Spectrum Disorders in Siblings of Indian Children With Autism Spectrum Disorders.

    PubMed

    Kumar, Ankur; Juneja, Monica; Mishra, Devendra

    2016-06-01

    This study determined the prevalence of autism spectrum disorders in 201 siblings of children with autism spectrum disorders. Siblings were screened using Modified Checklist for Autism in Toddlers and Social Responsiveness Scale, parent version. Screen-positive siblings were assessed using Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) criteria. The risk of autism spectrum disorder in siblings was correlated with various familial and disease characteristics of the index case. Prevalence of autism spectrum disorder in siblings was 4.97%. There was a significant effect of the presence of aggressive behavior, externalizing problems and total problems in the proband, assessed using Childhood Behavior Checklist, and the young age of the father at conception on sibling risk of autism spectrum disorder. Results of our study are in line with previous studies reporting similar prevalence but have also brought up the association with behavioral problems as a possible risk factor. Siblings of children with autism spectrum disorder should be routinely screened, and genetic counseling for this increased risk should be explained to the family. PMID:26733506

  2. Natural supersymmetric spectrum in mirage mediation

    NASA Astrophysics Data System (ADS)

    Asano, Masaki; Higaki, Tetsutaro

    2012-08-01

    The current results of LHC experiments exclude a large area of the light new particle region, namely, natural parameter space, in supersymmetric extension models. One of the possibilities for achieving the correct electroweak symmetry breaking naturally is the low-scale messenger scenario. Actually, the next-to-minimal supersymmetric standard model with TeV scale mirage mediation realizes the natural electroweak symmetry breaking with various mass spectra. In this paper, we show the possible mass spectrum in the scenario, e.g., the degenerate and/or hierarchical mass spectrum, and discuss these features.

  3. Risk Factors for Bullying among Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Zablotsky, Benjamin; Bradshaw, Catherine P.; Anderson, Connie M.; Law, Paul

    2014-01-01

    Although children with disabilities have been found to be at an increased risk of bullying, there are limited studies investigating predictors of bullying involvement in children with autism spectrum disorders. The current study presents findings from 1221 parents of children diagnosed with autism spectrum disorder who were selected from a…

  4. Compact Microwave Fourier Spectrum Analyzer

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy; Matsko, Andrey; Strekalov, Dmitry

    2009-01-01

    A compact photonic microwave Fourier spectrum analyzer [a Fourier-transform microwave spectrometer, (FTMWS)] with no moving parts has been proposed for use in remote sensing of weak, natural microwave emissions from the surfaces and atmospheres of planets to enable remote analysis and determination of chemical composition and abundances of critical molecular constituents in space. The instrument is based on a Bessel beam (light modes with non-zero angular momenta) fiber-optic elements. It features low power consumption, low mass, and high resolution, without a need for any cryogenics, beyond what is achievable by the current state-of-the-art in space instruments. The instrument can also be used in a wide-band scatterometer mode in active radar systems.

  5. Nonlinear Single Spin Spectrum Analyzer

    NASA Astrophysics Data System (ADS)

    Kotler, Shlomi; Akerman, Nitzan; Glickman, Yinnon; Ozeri, Roee

    2014-03-01

    Qubits have been used as linear spectrum analyzers of their environments, through the use of decoherence spectroscopy. Here we solve the problem of nonlinear spectral analysis, required for discrete noise induced by a strongly coupled environment. Our nonperturbative analytical model shows a nonlinear signal dependence on noise power, resulting in a spectral resolution beyond the Fourier limit as well as frequency mixing. We develop a noise characterization scheme adapted to this nonlinearity. We then apply it using a single trapped ion as a sensitive probe of strong, non-Gaussian, discrete magnetic field noise. Finally, we experimentally compared the performance of equidistant vs Uhrig modulation schemes for spectral analysis. Phys. Rev. Lett. 110, 110503 (2013). Synopsis at http://physics.aps.org/synopsis-for/10.1103/PhysRevLett.110.110503 Current position: NIST, Boulder, CO.

  6. Economics of spectrum allocation

    NASA Astrophysics Data System (ADS)

    Melody, W. H.

    The effective and efficient allocation and use of the spectrum can be ensured only by a set of sharing rules that will reflect the interests, values, and power of all affected parties. What is now happening is that the new interests and different values of the developing countries are pressing to change the international sharing rules established by a small group of high-technology nations. It is noted that the latter have established a massive telecommunications infrastructure on the basis of inherited sharing rules that reflect only their interests and a much simplified scarcity problem. Once long-term goals and underlying principles of allocation are established, communication technologies and markets can be directed, through a series of adjustment policies, to achieve them. A crucial first step in the creation of an international information environment in which 'free' flows will be balanced flows is the establishment of a balanced and equitable set of sharing rules for the radio spectrum.

  7. Spread spectrum image steganography.

    PubMed

    Marvel, L M; Boncelet, C R; Retter, C T

    1999-01-01

    In this paper, we present a new method of digital steganography, entitled spread spectrum image steganography (SSIS). Steganography, which means "covered writing" in Greek, is the science of communicating in a hidden manner. Following a discussion of steganographic communication theory and review of existing techniques, the new method, SSIS, is introduced. This system hides and recovers a message of substantial length within digital imagery while maintaining the original image size and dynamic range. The hidden message can be recovered using appropriate keys without any knowledge of the original image. Image restoration, error-control coding, and techniques similar to spread spectrum are described, and the performance of the system is illustrated. A message embedded by this method can be in the form of text, imagery, or any other digital signal. Applications for such a data-hiding scheme include in-band captioning, covert communication, image tamperproofing, authentication, embedded control, and revision tracking. PMID:18267522

  8. MEASURING THE JET POWER OF FLAT-SPECTRUM RADIO QUASARS

    SciTech Connect

    Shabala, S. S.; Santoso, J. S.; Godfrey, L. E. H.

    2012-09-10

    We use frequency-dependent position shifts of flat-spectrum radio cores to estimate the kinetic power of active galactic nucleus (AGN) jets. We find a correlation between the derived jet powers and AGN narrow-line luminosity, consistent with the well-known relation for radio galaxies and steep spectrum quasars. This technique can be applied to intrinsically weak jets even at high redshift.

  9. The marine diversity spectrum.

    PubMed

    Reuman, Daniel C; Gislason, Henrik; Barnes, Carolyn; Mélin, Frédéric; Jennings, Simon

    2014-07-01

    Distributions of species body sizes within a taxonomic group, for example, mammals, are widely studied and important because they help illuminate the evolutionary processes that produced these distributions. Distributions of the sizes of species within an assemblage delineated by geography instead of taxonomy (all the species in a region regardless of clade) are much less studied but are equally important and will illuminate a different set of ecological and evolutionary processes. We develop and test a mechanistic model of how diversity varies with body mass in marine ecosystems. The model predicts the form of the 'diversity spectrum', which quantifies the distribution of species' asymptotic body masses, is a species analogue of the classic size spectrum of individuals, and which we have found to be a new and widely applicable description of diversity patterns. The marine diversity spectrum is predicted to be approximately linear across an asymptotic mass range spanning seven orders of magnitude. Slope -0.5 is predicted for the global marine diversity spectrum for all combined pelagic zones of continental shelf seas, and slopes for large regions are predicted to lie between -0.5 and -0.1. Slopes of -0.5 and -0.1 represent markedly different communities: a slope of -0.5 depicts a 10-fold reduction in diversity for every 100-fold increase in asymptotic mass; a slope of -0.1 depicts a 1.6-fold reduction. Steeper slopes are predicted for larger or colder regions, meaning fewer large species per small species for such regions. Predictions were largely validated by a global empirical analysis. Results explain for the first time a new and widespread phenomenon of biodiversity. Results have implications for estimating numbers of species of small asymptotic mass, where taxonomic inventories are far from complete. Results show that the relationship between diversity and body mass can be explained from the dependence of predation behaviour, dispersal, and life history on

  10. Measurements of Spectral Line Strengths Within some CI Multiplets Belonging to the 3p-3d and 3p-4s Transition Arrays

    NASA Astrophysics Data System (ADS)

    Bacawski, A.; Wujec, T.; Musielok, J.

    With a high-current wall-stabilized arc, operated in helium with small admixtures of CO2, relative line strengths for some prominent infrared multiplets of neutral carbon have been measured. The results are analyzed in conjunction with previously obtained experimental data in the visible and near infrared region of the spectrum. Our experimental results are compared with those resulting from the Russell-Saunders coupling scheme and with recent sophisticated intermediate coupling calculations. The results of this paper may be helpful for the improvement of atomic structure codes used for line strength calculations. The determined relative line strengths may also be useful in astrophysical applications.

  11. The status of neutral currents

    SciTech Connect

    Zwirner, F.

    1987-11-01

    The situation of particle physics today is quite puzzling. On the one hand, the Standard Model (SM) of strong and electroweak interactions is consistent with all confirmed experimental data but theoretically rather unsatisfactory. On the other hand, none of the many theoretical speculations which try to go beyond the SM has (yet) received the slightest experimental support. The solution to this dilemma can only come from new data: either from the detection of a new particle threshold at high energy colliders, or from the appearance of some small discrepancy in high-precision experiments. A crucial sector for testing the SM and its extensions is that of neutral currents (NC), where an impressive amount of data has been collected in recent years. While waiting for the next generation of experiments, it is certainly useful to take stock of our knowledge, determining the NC parameters as precisely as we can and putting limits on possible deviations from the SM. The present talk contains the results of a recent analysis along these lines: the first part illustrates how a set of 'model-independent' parameters can be extracted from the available NC data, the second part particularizes the analysis to the SM and to some superstring-inspired models with an additional Z' in their low-energy spectrum. 27 refs., 3 figs., 1 tab.

  12. Characteristic impedance of microstrip lines

    NASA Technical Reports Server (NTRS)

    Bailey, M. C.; Deshpande, M. D.

    1989-01-01

    The dyadic Green's function for a current embedded in a grounded dielectric slab is used to analyze microstrip lines at millimeter wave frequencies. The dyadic Green's function accounts accurately for fringing fields and dielectric cover over the microstrip line. Using Rumsey's reaction concept, an expression for the characteristic impedance is obtained. The numerical results are compared with other reported results.

  13. Current sensor

    DOEpatents

    Yakymyshyn, Christopher Paul; Brubaker, Michael Allen; Yakymyshyn, Pamela Jane

    2007-01-16

    A current sensor is described that uses a plurality of magnetic field sensors positioned around a current carrying conductor. The sensor can be hinged to allow clamping to a conductor. The current sensor provides high measurement accuracy for both DC and AC currents, and is substantially immune to the effects of temperature, conductor position, nearby current carrying conductors and aging.

  14. Neutrino spectrum at the far detector systematic errors

    SciTech Connect

    Szleper, M.; Para, A.

    2001-10-01

    Neutrino oscillation experiments often employ two identical detectors to minimize errors due to inadequately known neutrino beam. We examine various systematics effects related to the prediction of the neutrino spectrum in the `far' detector on the basis of the spectrum observed at the `near' detector. We propose a novel method of the derivation of the far detector spectrum. This method is less sensitive to the details of the understanding of the neutrino beam line and the hadron production spectra than the usually used `double ratio' method thus allowing to reduce the systematic errors.

  15. The transition between BL Lac objects and flat spectrum radio quasars

    NASA Astrophysics Data System (ADS)

    Ghisellini, G.; Tavecchio, F.; Foschini, L.; Ghirlanda, G.

    2011-07-01

    We study the BL Lac objects detected in the 1-year all-sky survey of the Fermi satellite, with an energy spectral slope αγ in the 0.1-100 GeV band greater than 1.2. In the αγ versus γ-ray luminosity plane, these BL Lacs occupy the region populated by flat spectrum radio quasars (FSRQs). Studying the properties of their spectral energy distributions (SEDs) and of their emitting lines, we find that several of these BL Lacs have an SED similar to FSRQs and that they do have broad lines of large equivalent width (EW), and should be reclassified as FSRQs even adopting the current phenomenological definition (i.e. EW of the emitting line greater than 5 Å). In other cases, even if the EW is small, the emitting lines can be as luminous as in quasars, and again their SED is similar to the SED of FSRQs. Sources classified as BL Lacs with an SED appearing as intermediate between BL Lacs and FSRQs also have relatively weak broad emission lines and small EW, and can be considered as transition sources. These properties are confirmed also by model fitting that allows us to derive the relevant intrinsic jet parameters and the jet power. This study leads us to propose a physical distinction between the two classes of blazars, based on the luminosity of the broad-line region measured in Eddington units. The dividing line is of the order of LBLR/LEdd˜ 5 × 10-4, in good agreement with the idea that the presence of strong emitting lines is related to a transition in the accretion regime, becoming radiatively inefficient below a disc luminosity of the order of 1 per cent of the Eddington one.

  16. The 3 micron spectrum of the classical Be star Beta Monocerotis A

    NASA Technical Reports Server (NTRS)

    Sellgren, K.; Smith, R. G.

    1992-01-01

    A 3.1-3.7-micron spectrum of the classical Be star Beta Mon A is presented at a resolution of lambda/Delta-lambda of 700-800. The spectrum shows strong hydrogen recombination lines, including Pf-delta and a series of Humphreys lines from Hu 19 to Hu 28. The relative recombination line strengths suggest that Pf-delta has a large optical depth. The Humphreys lines have relative strengths consistent with case B and may be optically thin. The line widths observed are broader than the Balmer lines and similar in width to Fe II lines, consistent with a disk model in which optically thinner lines arise primarily from a faster rotating inner disk, while optically thicker lines come mainly from a slower rotating outer disk. The apparent lack of Stark broadening of the Humphreys lines is used to place an upper limit on the circumstellar electron density of about 10 exp 12/cu cm.

  17. Predicted ICF Neutron Spectrum Corrections from Simulation

    NASA Astrophysics Data System (ADS)

    Field, John; Munro, Dave; Spears, Brian; Peterson, Luc; Brandon, Scott; Gaffney, Jim; Hammer, Jim; Kritcher, Andrea; Nora, Ryan; Springer, Paul

    2015-11-01

    Produced neutron spectra have long been used as a diagnostic of ICF implosions. The neutron spectrum width is characteristic of the burn temperature as well as the variance of the burning region's fluid motion. Corrections to higher moments of the spectrum are thought to be diagnostic as well. Because of the large neutron fluxes at the NIF, we expect to have the opportunity to measure these corrections and compare with simulation. We will discuss a post-process platform that we have built for extracting these moment corrections as well as many other extensive quantities from the hydrodynamic simulations, and report on the predicted neutron spectrum corrections recently calculated for a large suite of implosion simulations in one, two, and three dimensions with varying drive symmetry and overall convergence ratio. We are particularly interested in the observable effects on the neutron spectrum along different lines of sight from the dimensional symmetry constraint in the simulated hydrodynamics. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  18. FB Line Basis for Interim Operation

    SciTech Connect

    Shedrow, B.

    1998-10-19

    The safety analysis of the FB-Line Facility indicates that the operation of FB-Line to support the current mission does not present undue risk to the facility and co-located workers, general public, or the environment.

  19. Fetal Alcohol Spectrum Disorders (FASDs)

    MedlinePlus

    ... FASD Cancel Submit Search The CDC Fetal Alcohol Spectrum Disorders (FASDs) Note: Javascript is disabled or is ... Recommend on Facebook Tweet Share Compartir Fetal alcohol spectrum disorders (FASDs) are a group of conditions that ...

  20. The spectrum of NGC 7027 (367-650 nm)

    PubMed Central

    Aller, Lawrence H.; Keyes, Charles D.

    1988-01-01

    NGC 7027 shows the richest spectrum of any known gaseous nebula. In the region of the spectrum surveyed we have measured lines of ions of H, He, C, N, O, F, Ne, Mg, Si, P, S, Cl, Ar, K, Ca, Mn, and Fe using the new Hamilton Echelle Spectrograph of Lick Observatory with a charge-coupled device (CCD) detector. Since a CCD is a linear detector, whereas photographic emulsions used in the most comprehensive previous studies were not, a considerable enhancement in the accuracy of line intensity measurements is possible. PMID:16593920

  1. Very deep spectroscopy of the bright Saturn nebula NGC 7009 - II. Analysis of the rich optical recombination spectrum

    NASA Astrophysics Data System (ADS)

    Fang, X.; Liu, X.-W.

    2013-03-01

    In Paper I, we presented a deep, long-slit spectrum of the bright Saturn nebula NGC 7009. Numerous permitted lines emitted by the C+, N+, O+ and Ne+ ions were detected. Gaussian profile fitting to the spectrum yielded more than 1000 lines, the majority of which are optical recombination lines (ORLs) of heavy-element ions. In the current paper, we present a critical analysis of the rich optical recombination spectrum of NGC 7009, in the context of the bi-abundance nebular model proposed by Liu et al. Transitions from individual multiplets are checked carefully for potential blended lines. The observed relative intensities are compared with the theoretical predictions based on high-quality effective recombination coefficients, now available for the recombination line spectrum of a number of heavy-element ions. The possibility of plasma diagnostics using the ORLs of various heavy-element ions is discussed in detail. The line ratios that can be used to determine electron temperature are presented for each ion, although there is still a lack of adequate atomic data and some of the lines are still not detected in the spectrum of NGC 7009 due to weakness and/or line blending. Plasma diagnostics based on the N II and O II recombination spectra both yield electron temperatures close to 1000 K, which is lower than those derived from the collisionally excited line (CEL) ratios (e.g. the [O III] and [N II] nebular-to-auroral line ratios; see Paper I for details) by nearly one order of magnitude. The very low temperatures yielded by the O II and N II ORLs indicate that they originate from very cold regions. The C2+/H+, N2+/H+, O2+/H+ and Ne2+/H+ ionic abundance ratios derived from ORLs are consistently higher, by about a factor of 5, than the corresponding values derived from CELs. In calculating the ORL ionic abundance ratios, we have used the newly available high-quality effective recombination coefficients, and adopted an electron temperature of ˜1000 K, as given by the ORL

  2. Hybrid spread spectrum radio system

    DOEpatents

    Smith, Stephen F [London, TN; Dress, William B [Camas, WA

    2010-02-09

    Systems and methods are described for hybrid spread spectrum radio systems. A method, includes receiving a hybrid spread spectrum signal including: fast frequency hopping demodulating and direct sequence demodulating a direct sequence spread spectrum signal, wherein multiple frequency hops occur within a single data-bit time and each bit is represented by chip transmissions at multiple frequencies.

  3. Fluorescence excitation spectrum of bilirubin in blood: a model for the action spectrum for phototherapy of neonatal jaundice.

    PubMed

    Lamola, Angelo A; Russo, Marie

    2014-01-01

    A recent report (Lamola et al. 2013 Pediatric Research, 74, 54-60) presents a semiempirical model for facile calculation of an action spectrum for bilirubin photochemistry in vivo using the most current knowledge of the optics of neonatal skin. The calculations indicate that competition for phototherapy light by hemoglobin in the skin is the predominant factor that defines the spectrum of light absorbed by bilirubin. If the latter is correct, a valid physical analog of the calculated spectrum is the excitation spectrum of bilirubin in blood. The fluorescence excitation spectrum was recorded and, indeed, found to be very similar to the calculated spectrum. Both spectra exhibit maxima near 476 nm and widths at half height of about 50 nm. This result supports the conclusion that light between 460 and 490 nm is most effective for phototherapy of neonatal jaundice. PMID:23998276

  4. LINE-BY-LINE CALCULATION OF SPECTRA FROM DIATOMIC MOLECULES AND ATOMS ASSUMING A VOIGT LINE PROFILE

    NASA Technical Reports Server (NTRS)

    Whiting, E. E.

    1994-01-01

    This program predicts the spectra resulting from electronic transitions of diatomic molecules and atoms in local thermodynamic equilibrium. The program produces a spectrum by accounting for the contribution of each rotational and atomic line considered. The integrated intensity of each line is distributed in the spectrum by an approximate Voigt profile. The program can produce spectra for optically thin gases or for cases where simultaneous emission and absorption occurs. In addition, the program can compute the spectrum resulting from the absorption of incident radiation by a column of cold gas or the high-temperature, self-absorbed emission spectrum from a nonisothermal gas. The computed spectrum can be output directly or combined with a slit function and sensitivity calibration to predict the output of a grating spectrograph or a fixed wavelength radiometer. Specifically, the program has the capability to include the following features in any computations: (1) Parallel transitions, in which spin splitting and lambda doubling are ignored (ignoring spin splitting and/or lambda doubling means that the total multiple strength is assumed to reside in a single "effective" line), (2) Perpendicular transitions, in which spin splitting and lambda doubling are ignored, (3) Sigma Pi transitions, in which lambda doubling is ignored, (4) Atomic lines, (5) Option to terminate rotational line calculations when the molecule dissociates due to rotation, (6) Option to include the alternation of line intensities for homonuclear molecules, (7) Use of an approximate Voigt profile for the line shape, and (8) Radiative energy transport in a nonisothermal gas. The output options available in the program are: (1) Tabulation of the spontaneous emission spectrum (i.e., optically thin spectrum) for a 1.0 cm path length, (2) Tabulation of the "true" spectrum, which incorporates spontaneous emission, induced emission, absorption, and externally incident radiation through the equation of

  5. Acoustooptical spectrum analysis modeling

    NASA Astrophysics Data System (ADS)

    Carmody, M. J.

    1981-06-01

    A summary of Bragg deflection theory and various approaches to direct detection acoustooptic spectrum analysis (AOSA) modeling is presented. A suitable model is chosen and extended to include the effects of diffraction efficiency, transducer efficiency, irradiance profiles of incident laser illumination, aperture size of the Bragg cell, and the acoustic attenuation experienced by the acoustic wavetrain generated by the input r-f signal. A FORTRAN program is developed to model the AOSA and predict the output image plane intensity profiles. A second version of the program includes a time variable permitting dynamic simulation of the system response.

  6. Spectrum of Fascicular Arrhythmias.

    PubMed

    Sung, Raphael; Scheinman, Melvin

    2016-09-01

    Fascicular arrhythmias encompass a wide spectrum of ventricular arrhythmias that depend on the specialized conduction system of the right and left ventricles. These arrhythmias include premature ventricular complexes, monomorphic ventricular tachycardia, polymorphic ventricular tachycardia, and ventricular fibrillation. These arrhythmias may be organized by mechanism, including intrafascicular reentry, interfascicular reentry, and focal. Mapping and ablation of the fascicular system can result in high cure rates of debilitating and potentially life-threatening arrhythmias. When approaching these arrhythmias, careful consideration of the structure of the His Purkinje system as well as their electrophysiologic properties may help guide even the most complex of arrhythmias. PMID:27521090

  7. The Thz Spectrum of Glycolaldehyde

    NASA Astrophysics Data System (ADS)

    Goubet, Manuel; Huet, Therese R.; Haykal, Imane; Margules, Laurent; Pirali, Olivier; Roy, Pascale

    2011-06-01

    The vibration-rotation spectrum of the ν_1-0, ν_2-0 and ν_3-0 bands of glycolaldehyde was recorded up to 12 THz, using the far-infrared beamline AILES at the synchrotron SOLEIL and a Fourier transform spectrometer coupled to a multipass cell. More than eight thousands lines were assigned, revealing the rotation structure up to J=80, K_a=38 for the ground state. The THz data were fitted simultaneously with pure rotational transitions of better accuracy observed in the microwave (1), in the millimeter-wave (2) and in the sub-millimeter-wave (3) range. In addition new data were recorded at Lille in the 150-300 GHz and 750-950 GHz range. The THz lines and the microwave - (sub)-millimeterwave lines are reproduced with a standard deviation of 2 10-4 Cm-1 and 40 KHz, respectively. Glycolaldehyde has been identified toward the galactic center (4). The vibrational state partition function can be re-evaluated according to the bands origins associated with ν_1, ν_2, and ν_3, which are observed experimentally for the first time. This work is supported by the Programme National de Physico-Chimie du Milieu Interstellaire (PCMI-CNRS) and by the contract ANR-08-BLAN-0054. 1. M. Rey, J.-R. Aviles-Moreno and T. R. Huet, Chem. Phys. Lett. 430(2006) 121 ; K.-M. Marstokk and H. Mollendal, J. Mol. Struct. 5 (1970) 205. 2. R. A. H. Butler, F. C. De Lucia, D. T. Petkie, H. Mollendal, A. Horn, and E. Herbst, ApJS 134 (2001) 319. ; S. L. Widicus-Weaver, R. A. H. Butler, B. J. Drouin, D. T. Petkie, K. A. Dyl, F. C. De Lucia, and G. A. Blake, ApJ 158(2005)188. 3. P. B. Carroll, B. J. Drouin, and S. L. Widicus-Weaver, ApJ 723 (2010) 845. 4. J. M. Hollis, S. N. Vogel, L. E. Snyder, P. R. Jewell, and F. J. Lovas, ApJ 554 (2001) L81. ; M.T. Beltran, C. Codella, S. Viti, R. Niri, R. Cesaroni, ApJ 690 (2009) L93.

  8. A computer program for a line-by-line calculation of spectra from diatomic molecules and atoms assuming a Voight line profile

    NASA Technical Reports Server (NTRS)

    Arnold, J. O.; Lyle, G. C.; Whiting, E. E.

    1969-01-01

    Computer program predicts the spectra resulting from electronic transitions of diatomic molecules and atoms in local thermodynamic equilibrium. The program produces a spectrum by accounting for the contribution of each rotational and atomic line considered.

  9. Rocket spectrometer for investigation of the far ultraviolet solar spectrum

    NASA Technical Reports Server (NTRS)

    Parkinson, W. H.; Reeves, E. M.; Kohl, J. L.

    1974-01-01

    A rocket-borne Ebert spectrometer and telescope were used for analysis of the solar spectrum. The instrument was arranged in the high resolution line scanning mode. Selected emission lines between 1170 and 1640 A were scanned, and a complete wavelength scan was made from 1170 A to 1850 A. Accurate measurements were made of the line profiles of the He II lines at 1640 A, C IV lines at 1550 A, Si IV lines at 1400 A, C II lines at 1335 A, the N V lines at 1240 A, and the C III lines at 1175 A. Accurate intensity measurements of the quiet sun spectrum for wavelengths between 1174 A and 3220 A were obtained. Spectral resolution was better than 0.03 A over most of the range and spatial resolution was relatively low so that the observations are averaged over the chromospheric network. Plots of absolute intensity versus wave length were prepared for the full wavelength range of the observations.

  10. Spectral Synthesis of TiO Lines

    NASA Astrophysics Data System (ADS)

    Valenti, Jeff A.; Piskunov, Nikolai; Johns-Krull, Christopher M.

    1998-05-01

    We explore the extent to which current titanium oxide (TiO) line data and M dwarf model atmospheres can be used to reproduce an R = 120,000 optical spectrum of the relatively inactive star Gliese 725B (M3.5 V). We find that tabulated TiO wavelengths have errors large enough to complicate line identification, especially for transitions involving higher vibrational states. We determine empirical wavelength corrections for 12 strong γ-bands near 6680 and 7090 Å. For the sequence of orbital quantum numbers, J, within any one of these bands, our observations confirm the predicted line spacing, thereby validating the rotational constants for low vibrational levels. However, the predicted wavelengths have zero-point errors that differ for each overlapping band. Next, we compare observed and synthetic spectra near 8463 Å, where an ε Q3 0-0 band head is expected, demonstrating that the electronic oscillator strength of 0.014 advocated by Jørgensen is too large by at least a factor of 5. This has a minor effect on the structure of theoretical model atmospheres. Using our empirically corrected TiO wavelengths, we compute a grid of synthetic spectra for Allard & Hauschildt models spanning a range in effective temperature (Teff), surface gravity (log g), and metallicity ([M/H]). Interpolating in this grid of synthetic spectra, we simultaneously fit observations of the TiO band head region near 7088 Å and five Ti I and Fe I lines near 8683 Å. For Gl 725B, we find Teff = 3170 +/- 71 K, log g = 4.77 +/- 0.14, [M/H] = -0.92 +/- 0.07, and vmac = 1.1 +/- 0.7 km s-1. We show that by using both atomic and molecular lines as constraints, systematic uncertainties in derived stellar parameters can be reduced. These parameters are consistent with published values obtained by other means, but more stringent tests would be useful. In the Appendix, we tabulate wavelengths, identifications, relative line strengths, and other properties of the strongest band heads in the α, β, γ,

  11. Genomics and Autism Spectrum Disorder

    PubMed Central

    Johnson, Norah L.; Giarelli, Ellen; Lewis, Celine; Rice, Catherine E.

    2015-01-01

    Purpose To present the current state of the evidence regarding translation of genetics (the study of single genes) and genomics (the study of all genes and gene-gene or gene-environment interactions) into health care of children with autism spectrum disorder (ASD). Methods This article presents an overview of ASD as an international health challenge, the emerging science related to broad diagnostic criteria, and the role of the nurse in research, education, and practice. Findings Much progress is being made in the understanding of genetics and genomics of ASD. Environmental factors are thought to contribute to the risk of developing ASD by interacting with a number of genes in different ways, thus suggesting causal heterogeneity. The rising identified prevalence of ASD, the changing diagnostic criteria for ASD, and the complexity of the core and associated features have made it difficult to define the ASD phenotype (observable behaviors that result from gene-environment interaction). Because early identification improves opportunities for intervention, researchers are looking for a useful biomarker to detect ASD. This search is complicated by the likelihood that there are multiple causes for multiple expressions that are defined as the autism spectrum. Conclusions To date, genetic and genomic research on ASD have underscored the complexity of the causes of ASD indicating that there are very complex genetic processes involved that are still not well understood. Clinical Relevance Nurses will benefit from new knowledge related to early identification, diagnosis, and implications for the family to promote early intervention. Families who have a child with ASD will require nursing support for advocacy for optimal health outcomes. PMID:23368711

  12. ALFA: an automated line fitting algorithm

    NASA Astrophysics Data System (ADS)

    Wesson, R.

    2016-03-01

    I present the automated line fitting algorithm, ALFA, a new code which can fit emission line spectra of arbitrary wavelength coverage and resolution, fully automatically. In contrast to traditional emission line fitting methods which require the identification of spectral features suspected to be emission lines, ALFA instead uses a list of lines which are expected to be present to construct a synthetic spectrum. The parameters used to construct the synthetic spectrum are optimized by means of a genetic algorithm. Uncertainties are estimated using the noise structure of the residuals. An emission line spectrum containing several hundred lines can be fitted in a few seconds using a single processor of a typical contemporary desktop or laptop PC. I show that the results are in excellent agreement with those measured manually for a number of spectra. Where discrepancies exist, the manually measured fluxes are found to be less accurate than those returned by ALFA. Together with the code NEAT, ALFA provides a powerful way to rapidly extract physical information from observations, an increasingly vital function in the era of highly multiplexed spectroscopy. The two codes can deliver a reliable and comprehensive analysis of very large data sets in a few hours with little or no user interaction.

  13. Spectral line lists of a nitrogen gas discharge for wavelength calibration in the range 4500-11 000 cm-1

    NASA Astrophysics Data System (ADS)

    Boesch, A.; Reiners, A.

    2015-10-01

    Context. A discharge of nitrogen gas, as created in a microwave-induced plasma, exhibits a very dense molecular emission line spectrum. Emission spectra of this kind could serve as wavelength calibrators for high-resolution astrophysical spectrographs in the near-infrared, where only very few calibration sources are currently available. Aims: The compilation of a spectral line list and the characterization of line intensities and line density belong to the initial steps when investigating the feasibility of potential wavelength calibration sources. Although the molecular nitrogen spectrum was extensively studied in the past, to our knowledge, no line list exists that covers a continuous range of several thousand wavenumbers in the near-infrared. Methods: We recorded three high-resolution (Δ tilde{ν = 0.018} cm-1) spectra of a nitrogen gas discharge operated at different microwave powers. The nitrogen gas is kept inside a sealed glass cell at a pressure of 2 mbar. The emission lines in the spectra were fitted by a superposition of Gaussian profiles to determine their position, relative intensity, and width. The line parameters were corrected for an absolute wavelength scale, instrumental line broadening, and intensity modulation. Molecular and atomic transitions of nitrogen were identified with available line positions from the literature. Results: We report line lists with more than 40 000 emission lines in the spectral range 4500-11 000 cm-1 (0.9-2.2 μm). The spectra exhibit emission lines over the complete spectral range under investigation with about 350-1300 lines per 100 cm-1. Depending on the microwave power, a fraction of 35-55% of all lines are blended. The total dynamic range of the detected lines covers about four orders of magnitude. Conclusions: Line density and peak intensities qualify the recorded discharge as a useful wavelength calibrator, and the line list provides an empirical reference for nitrogen spectra in the near-infrared. The line lists

  14. A current monitoring system for diagnosing electrical failures in induction motors

    NASA Astrophysics Data System (ADS)

    Acosta, G. G.; Verucchi, C. J.; Gelso, E. R.

    2006-05-01

    Induction motors are critical components in industrial processes. A motor failure may yield an unexpected interruption at the industrial plant, with consequences in costs, product quality, and safety. Many of these faulty situations in three phase induction motors have an electrical reason. Among different detection approaches proposed in the literature, those based on stator current monitoring are advantageous due to its non-invasive properties. One of these techniques resorts to spectrum analysis of machine line current. Another non-invasive technique is the Extended Park's Vector Approach, which allows the detection of inter-turn short circuits in the stator winding. This article presents the development of an on-line current monitoring system that uses both techniques for fault detection and diagnosis in the stator and in the rotor. Based on experimental observations and on the knowledge of the electrical machine, a knowledge-based system was constructed in order to carry out the diagnosis task from these estimated data.

  15. The ultraviolet spectrum of KX Trianguli Australis

    SciTech Connect

    Feibelman, W.A. )

    1991-07-01

    Low-dispersion and high-dispersion IUE satellite observations of the symbiotic star KX TrA, carried out on May 7, 1990, are reported. The low-dispersion data show no significant changes from the observation data obtained a decade ago. Resonantly excited high-excitation Fe II emission lines are seen in the UV spectra of KX TrA, suggesting the existence of a very hot (greater than 60,000 K) subdwarf or white dwarf in the system. The S-type symbiotic KX TrA exhibits a UV spectrum that is nearly identical to that of the D-type symbiotic V1016 Cyg. 42 refs.

  16. Possibility of precise measurement of the cosmological power spectrum with a dedicated survey of 21 cm emission after reionization.

    PubMed

    Loeb, Abraham; Wyithe, J Stuart B

    2008-04-25

    Measurements of the 21 cm line emission by residual cosmic hydrogen after reionization can be used to trace the power spectrum of density perturbations through a significant fraction of the observable volume of the Universe. We show that a dedicated 21 cm observatory could probe a number of independent modes that is 2 orders of magnitude larger than currently available, and enable a cosmic-variance limited detection of the signature of a neutrino mass approximately 0.05 eV. The evolution of the linear growth factor with redshift could also constrain exotic theories of gravity or dark energy to an unprecedented precision. PMID:18518181

  17. Oxygen spectral line synthesis: 3D non-LTE with CO5BOLD hydrodynamical model atmospheres.

    NASA Astrophysics Data System (ADS)

    Prakapavičius, D.; Steffen, M.; Kučinskas, A.; Ludwig, H.-G.; Freytag, B.; Caffau, E.; Cayrel, R.

    In this work we present first results of our current project aimed at combining the 3D hydrodynamical stellar atmosphere approach with non-LTE (NLTE) spectral line synthesis for a number of key chemical species. We carried out a full 3D-NLTE spectrum synthesis of the oxygen IR 777 nm triplet, using a modified and improved version of our NLTE3D package to calculate departure coefficients for the atomic levels of oxygen in a CO5BOLD 3D hydrodynamical solar model atmosphere. Spectral line synthesis was subsequently performed with the Linfor3D code. In agreement with previous studies, we find that the lines of the oxygen triplet produce deeper cores under NLTE conditions, due to the diminished line source function in the line forming region. This means that the solar oxygen IR 777 nm lines should be stronger in NLTE, leading to negative 3D NLTE-LTE abundance corrections. Qualitatively this result would support previous claims for a relatively low solar oxygen abundance. Finally, we outline several further steps that need to be taken in order to improve the physical realism and numerical accuracy of our current 3D-NLTE calculations.

  18. Identification of interstellar methanol lines

    NASA Astrophysics Data System (ADS)

    Sutton, E. C.; Herbst, Eric

    1988-10-01

    The extended internal axis method Hamiltonian of Herbst et al. has been employed to study the rotational spectrum of methanol out to high values of the rotational quantum number J. For 12CH3OH the available laboratory data, consisting of 783 lines out to J = 22, have been fitted with a Hamiltonian containing 32 free parameters. For 13CH3OH a Hamiltonian with 23 free parameters is sufficient for fitting 455 lines, also out to J = 22. Frequency predictions based on these fits have permitted the identification of a number of previously unidentified interstellar lines from OMC-1. The majority of these are b-type R-branch transitions of 12CH3OH.

  19. Passive wide spectrum harmonic filter for adjustable speed drives in oil and gas industry

    NASA Astrophysics Data System (ADS)

    Al Jaafari, Khaled Ali

    Non-linear loads such as variable speed drives constitute the bulky load of oil and gas industry power systems. They are widely used in driving induction and permanent magnet motors for variable speed applications. That is because variable speed drives provide high static and dynamic performance. Moreover, they are known of their high energy efficiency and high motion quality, and high starting torque. However, these non-linear loads are main sources of current and voltage harmonics and lower the quality of electric power system. In fact, it is the six-pulse and twelve-pulse diode and thyristor rectifiers that spoil the AC power line with the dominant harmonics (5th, 7th, 11th). They provide DC voltage to the inverter of the variable speed drives. Typical problems that arise from these harmonics are Harmonic resonances', harmonic losses, interference with electronic equipment, and line voltage distortion at the Point of Common Coupling (PCC). Thus, it is necessary to find efficient, reliable, and economical harmonic filters. The passive filters have definite advantage over active filters in terms of components count, cost and reliability. Reliability and maintenance is a serious issue in drilling rigs which are located in offshore and onshore with extreme operating conditions. Passive filters are tuned to eliminate a certain frequency and therefore there is a need to equip the system with more than one passive filter to eliminate all unwanted frequencies. An alternative solution is Wide Spectrum Harmonic passive filter. The wide spectrum harmonic filters are becoming increasingly popular in these applications and found to overcome some of the limitations of conventional tuned passive filter. The most important feature of wide spectrum harmonic passive filters is that only one capacitor is required to filter a wide range of harmonics. Wide spectrum filter is essentially a low-pass filter for the harmonic at fundamental frequency. It can also be considered as a

  20. Discovery of a narrow line quasar

    NASA Technical Reports Server (NTRS)

    Stocke, J.; Liebert, J.; Maccacaro, T.; Griffiths, R. E.; Steiner, J. E.

    1982-01-01

    A stellar object is reported which, while having X-ray and optical luminosities typical of quasars, has narrow permitted and forbidden emission lines over the observed spectral range. The narrow-line spectrum is high-excitation, the Balmer lines seem to be recombinational, and a redder optical spectrum than that of most quasars is exhibited, despite detection as a weak radio source. The object does not conform to the relationships between H-beta parameters and X-ray flux previously claimed for a large sample of the active galactic nuclei. Because reddish quasars with narrow lines, such as the object identified, may not be found by the standard techniques for the discovery of quasars, the object may be a prototype of a new class of quasars analogous to high-luminosity Seyfert type 2 galaxies. It is suggested that these objects cannot comprise more than 10% of all quasars.

  1. Ocean color spectrum calculations

    NASA Technical Reports Server (NTRS)

    Mccluney, W. R.

    1974-01-01

    There is obvious value in developing the means for measuring a number of subsurface oceanographic parameters using remotely sensed ocean color data. The first step in this effort should be the development of adequate theoretical models relating the desired oceanographic parameters to the upwelling radiances to be observed. A portion of a contributory theoretical model can be described by a modified single scattering approach based on a simple treatment of multiple scattering. The resulting quasisingle scattering model can be used to predict the upwelling distribution of spectral radiance emerging from the sea. The shape of the radiance spectrum predicted by this model for clear ocean water shows encouraging agreement with measurements made at the edge of the Sargasso Sea off Cape Hatteras.

  2. Rotational spectrum of tryptophan

    SciTech Connect

    Sanz, M. Eugenia Cabezas, Carlos Mata, Santiago Alonso, Josè L.

    2014-05-28

    The rotational spectrum of the natural amino acid tryptophan has been observed for the first time using a combination of laser ablation, molecular beams, and Fourier transform microwave spectroscopy. Independent analysis of the rotational spectra of individual conformers has conducted to a definitive identification of two different conformers of tryptophan, with one of the observed conformers never reported before. The analysis of the {sup 14}N nuclear quadrupole coupling constants is of particular significance since it allows discrimination between structures, thus providing structural information on the orientation of the amino group. Both observed conformers are stabilized by an O–H···N hydrogen bond in the side chain and a N–H···π interaction forming a chain that reinforce the strength of hydrogen bonds through cooperative effects.

  3. Autism spectrum disorders

    PubMed Central

    Faras, Hadeel; Al Ateeqi, Nahed; Tidmarsh, Lee

    2010-01-01

    Pervasive developmental disorders are a group of neurodevelopmental disorders characterized by impairments in communication, reciprocal social interaction and restricted repetitive behaviors or interests. The term autism spectrum disorders (ASD) has been used to describe their variable presentation. Although the cause of these disorders is not yet known, studies strongly suggest a genetic basis with a complex mode of inheritance. More research is needed to explore environmental factors that could be contributing to the cause of these disorders. The occurrence of ASD has been increasing worldwide, with the most recent prevalence studies indicating that they are present in 6 per 1000 children. The objectives of this article are to provide physicians with relevant information needed to identify and refer children presenting with symptoms suggestive of ASDs to specialized centers early, and to make them feel comfortable in dealing with public concerns regarding controversial issues about the etiology and management of these disorders. PMID:20622347

  4. HD 207651: A composite spectrum triple system

    SciTech Connect

    Fekel, Francis C.

    2015-02-01

    From numerous radial velocities obtained at KPNO and Fairborn Observatory, we have determined the orbital elements of the composite spectrum triple system HD 207651. This system consists of a broad-lined A8 V star and an unseen M dwarf companion in a 1.470739 days orbit. Variations of the center-of-mass velocity of this short-period system and velocity variations of a narrow-lined F7: V star have an orbital period of 724.1 days or 1.98 yr and an eccentricity of 0.39. The revised Hipparcos parallax, corresponding to a distance of 255 pc, appears to be too small to yield consistent properties. Instead, we adopt a distance of 150 pc.

  5. Uranus - Variability of the microwave spectrum

    NASA Technical Reports Server (NTRS)

    Gulkis, S.; Olsen, E. T.; Klein, M. J.; Thompson, T. J.

    1983-01-01

    Radio astronomical observations of Uranus show that the radio emission spectrum is evolving in time. Ammonia vapor must be depleted in the Uranian atmosphere as Gulkis et al. (1978) previously suggested. Since 1965, ammonia either has been decreasing in time or is a decreasing function of latitude, or both, provided that the radio emission is atmospheric in origin. If Uranus has an observable low-emissivity 'surface', these trends may be reversed. The microwave observations made in 1965, at the time when the spin axis of Uranus was nearly perpendicular to the sun-Uranus line, are consistent with an atmospheric opacity profile that would be produced by saturated ammonia vapor in a predominantly hydrogen atmosphere. At the present time, when the spin axis of Uranus is nearly aligned with the sun-Uranus line, the measurements require an opacity that would be produced by saturated water vapor. A large thermal gradient between the pole and equator is ruled out.

  6. The Spectrum of Th-Ar Hollow Cathode Lamps in the 691nm to 5804nm region Database

    National Institute of Standards and Technology Data Gateway

    SRD 161 The Spectrum of Th-Ar Hollow Cathode Lamps in the 691nm to 5804nm region Database (Web, free access)   This atlas presents observations of the infra-red (IR) spectrum of a low current Th-Ar hollow cathode lamp with the 2-m Fourier transform spectrometer (FTS) at NIST. These observations establish more than 2400 lines that are suitable for use as wavelength standards in the range 691 nm to 5804 nm. The observations were made in collaboration with the European Southern Observatory (ESO), in order to provide calibration reference data for new high-resolution Echelle spectrographs, such as the Cryogenic High-Resolution IR Echelle Spectrograph ([CRIRES]), ESO's new IR spectrograph at the Very Large Telescope in Chile.

  7. Broad spectrum bioactive sunscreens.

    PubMed

    Velasco, Maria Valéria Robles; Sarruf, Fernanda Daud; Salgado-Santos, Idalina Maria Nunes; Haroutiounian-Filho, Carlos Alberto; Kaneko, Telma Mary; Baby, André Rolim

    2008-11-01

    The development of sunscreens containing reduced concentration of chemical UV filters, even though, possessing broad spectrum effectiveness with the use of natural raw materials that improve and infer UV absorption is of great interest. Due to the structural similarities between polyphenolic compounds and organic UV filters, they might exert photoprotection activity. The objective of the present research work was to develop bioactive sunscreen delivery systems containing rutin, Passiflora incarnata L. and Plantago lanceolata extracts associated or not with organic and inorganic UV filters. UV transmission of the sunscreen delivery system films was performed by using diffuse transmittance measurements coupling to an integrating sphere. In vitro photoprotection efficacy was evaluated according to the following parameters: estimated sun protection factor (SPF); Boot's Star Rating category; UVA/UVB ratio; and critical wavelength (lambda(c)). Sunscreen delivery systems obtained SPF values ranging from 0.972+/-0.004 to 28.064+/-2.429 and bioactive compounds interacted with the UV filters positive and negatively. This behavior may be attributed to: the composition of the delivery system; the presence of inorganic UV filter and quantitative composition of the organic UV filters; and the phytochemical composition of the P. incarnata L. and P. lanceolata extracts. Among all associations of bioactive compounds and UV filters, we found that the broad spectrum sunscreen was accomplished when 1.68% (w/w) P. incarnata L. dry extract was in the presence of 7.0% (w/w) ethylhexyl methoxycinnamate, 2.0% (w/w) benzophenone-3 and 2.0% (w/w) TiO(2). It was demonstrated that this association generated estimated SPF of 20.072+/-0.906 and it has improved the protective defense against UVA radiation accompanying augmentation of the UVA/UVB ratio from 0.49 to 0.52 and lambda(c) from 364 to 368.6nm. PMID:18662760

  8. Radio properties of Compact Steep Spectrum and GHz-Peaked Spectrum radio sources

    NASA Astrophysics Data System (ADS)

    Orienti, M.

    2016-02-01

    Compact steep spectrum (CSS) and GHz-peaked spectrum (GPS) radio sources represent a large fraction of the extragalactic objects in flux density-limited samples. They are compact, powerful radio sources whose synchrotron peak frequency ranges between a few hundred MHz to several GHz. CSS and GPS radio sources are currently interpreted as objects in which the radio emission is in an early evolutionary stage. In this contribution I review the radio properties and the physical characteristics of this class of radio sources, and the interplay between their radio emission and the ambient medium of the host galaxy.

  9. The broadband spectrum of Centaurus X-3

    NASA Astrophysics Data System (ADS)

    Gottlieb, Amy; Pottschmidt, Katja; Marcu, Diana; Wolff, Michael Thomas; Kühnel, Matthias; Falkner, Sebastian; Britton Hemphill, Paul; Suchy, Slawomir; Becker, Peter A.; Wood, Kent S.; Wilms, Joern

    2016-04-01

    We present an analysis of a Suzaku observation of the accreting pulsar and high mass X-ray binary Centaurus X-3. The observation was performed in 2008 and covers one 2.1 day binary orbit. Strong flux and hardness variability is present in the energy range from 0.8 to 60 keV. We selected a part of the observation covering ~40% of the first half of the orbit during which the spectral shape was stable and less absorbed than during other parts of the observation. We confirm earlier results that the broadband spectrum can be modeled with acutoff power law modified by a partial absorber, three iron lines -- from near-neutral, helium-like, and hydrogen-like iron --, and a cyclotron resonant scattering line at 30 keV. The pulse profile shows a shift above the cyclotron line energy which is qualitatively consistent with recent theoretical predictions. In addition we findthat the presence of the so-called ``13 keV'' bump is model dependent and that there are indications for further line-like spectral components at 1 keV and 6 keV and a broader residual around 2 keV. We also apply the newly implemented radiation dominated radiative shock model for luminous accretion pulsars by Becker and Wolff (2007, ApJ 654, 435) to model the broadband spectrum. Replacing the cutoff power law with the physical continuum while retaining all other components we obtain a similar goodness of fit as before. From the physical continuum model we determine a mass accretion rate of ~2.17 x 10^17 g/s, an accretion column radius of 65 (+12, -4) m, and a temperature of the accreted plasma of 3.1 (+0.4, -0.1) keV.

  10. Vacuum-ultraviolet spectrum of neutral boron /B I/.

    NASA Technical Reports Server (NTRS)

    Goorvitch, D.; Valero, F. P. J.

    1972-01-01

    Use of a hollow-cathode light source to produce the vacuum-ultraviolet spectrum of B I. One transition is resolved, and four transitions have been remeasured to a higher accuracy than previously because of the sharper lines emitted by the hollow-cathode light source. A revised value for one transition term results from these measurements.-

  11. Early Onset Bipolar Spectrum Disorder: Psychopharmacological, Psychological, and Educational Management

    ERIC Educational Resources Information Center

    McIntosh, David E.; Trotter, Jeffrey S.

    2006-01-01

    Although published research continues to advocate medication as the first line of treatment for early onset bipolar spectrum disorder (EOBSD; N. Lofthouse & M.A. Fristad, 2004), preliminary research demonstrating the utility of cognitive, cognitive-behavioral, and psychoeducational therapies is promising. It appears as if future treatment of EOBSD…

  12. Perception of Mirror Symmetry in Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Falter, Christine M.; Bailey, Anthony J.

    2012-01-01

    Gestalt grouping in autism spectrum disorders (ASD) is selectively impaired for certain organization principles but for not others. Symmetry is a fundamental Gestalt principle characterizing many biological shapes. Sensitivity to symmetry was tested using the Picture Symmetry Test, which requires finding symmetry lines on pictures. Individuals…

  13. Nonlinear Simulation of the Tooth Enamel Spectrum for EPR Dosimetry

    NASA Astrophysics Data System (ADS)

    Kirillov, V. A.; Dubovsky, S. V.

    2016-07-01

    Software was developed where initial EPR spectra of tooth enamel were deconvoluted based on nonlinear simulation, line shapes and signal amplitudes in the model initial spectrum were calculated, the regression coefficient was evaluated, and individual spectra were summed. Software validation demonstrated that doses calculated using it agreed excellently with the applied radiation doses and the doses reconstructed by the method of additive doses.

  14. Spread spectrum applications in unmanned aerial vehicles

    NASA Astrophysics Data System (ADS)

    Bess, Philip K.

    1994-06-01

    This thesis is part of an ongoing Naval Postgraduate School research project to develop unmanned aerial vehicles (UAV's) using current off the shelf (COTS) technology. This thesis specifically evaluated a spread spectrum UHF data link between a UAV and ground terminal. The command and control (C2) process and its role as the fundamental premise of the warfare commander were discussed. A review of the Pioneer remotely piloted vehicle (RPV), which gained such wide recognition during Operations Desert Storm and Desert Shield, was provided to the reader for familiarization with the workings of a generic UAV. An investigation of two common spread spectrum techniques and their associated benefits was made. A link budget calculation was made. The choice of a spread spectrum radio transceiver was reviewed. The requirements and design of the UAV and ground terminal antenna were discussed. A link budget analysis was performed. An atmospheric path propagation prediction was performed. The details of an actual flight test and the data gathered were examined. Future changes to enhance the data link performance and increase its capabilities were introduced. The COTS spread spectrum data link will enhance the role of the UAV in its command and control mission for the warfare commander.

  15. Field Line Resonances in Quiet and Disturbed Time Three-dimensional Magnetospheres

    SciTech Connect

    C.Z. Cheng; S. Zaharia

    2002-05-30

    Numerical solutions for field line resonances (FLR) in the magnetosphere are presented for three-dimensional equilibrium magnetic fields represented by two Euler potentials as B = -j Y -a, where j is the poloidal flux and a is a toroidal angle-like variable. The linearized ideal-MHD equations for FLR harmonics of shear Alfvin waves and slow magnetosonic modes are solved for plasmas with the pressure assumed to be isotropic and constant along a field line. The coupling between the shear Alfvin waves and the slow magnetosonic waves is via the combined effects of geodesic magnetic field curvature and plasma pressure. Numerical solutions of the FLR equations are obtained for a quiet time magnetosphere as well as a disturbed time magnetosphere with a thin current sheet in the near-Earth region. The FLR frequency spectra in the equatorial plane as well as in the auroral latitude are presented. The field line length, magnetic field intensity, plasma beta, geodesic curvature and pressure gradient in the poloidal flux surface are important in determining the FLR frequencies. In general, the computed shear Alfvin FLR frequency based on the full MHD model is larger than that based on the commonly adopted cold plasma model in the beq > 1 region. For the quiet time magnetosphere, the shear Alfvin resonance frequency decreases monotonically with the equatorial field line distance, which reasonably explains the harmonically structured continuous spectrum of the azimuthal magnetic field oscillations as a function of L shell in the L is less than or equal to 9RE region. However, the FLR frequency spectrum for the disturbed time magnetosphere with a near-Earth thin current sheet is substantially different from that for the quiet time magnetosphere for R > 6RE, mainly due to shorter field line length due to magnetic field compression by solar wind, reduced magnetic field intensity in the high-beta current sheet region, azimuthal pressure gradient, and geodesic magnetic field

  16. Superfine resolution acoustooptic spectrum analysis

    NASA Technical Reports Server (NTRS)

    Ansari, Homayoon; Lesh, James R.

    1991-01-01

    High resolution spectrum analysis of RF signals is required in applications such as the search for extraterrestrial intelligence, RF interference monitoring, or general purpose decomposition of signals. Sub-Hertz resolution in three-dimensional acoustooptic spectrum analysis is theoretically and experimentally demonstrated. The operation of a two-dimensional acoustooptic spectrum analyzer is extended to include time integration over a sequence of CCD frames.

  17. Inexpensive Eddy-Current Standard

    NASA Technical Reports Server (NTRS)

    Berry, Robert F., Jr.

    1985-01-01

    Radial crack replicas serve as evaluation standards. Technique entails intimately joining two pieces of appropriate aluminum alloy stock and centering drilled hole through and along interface. Bore surface of hole presents two vertical stock interface lines 180 degrees apart. These lines serve as radial crack defect replicas during eddy-current technique setup and verification.

  18. The submillimeter-wave spectrum of diisocyanomethane

    NASA Astrophysics Data System (ADS)

    Motiyenko, R. A.; Margulès, L.; Guillemin, J.-C.

    2012-08-01

    Context. Several organic isocyanides (HNC, CH3NC, HCCNC) have been observed to date in the interstellar medium (ISM). However there is still a lack of high-resolution spectroscopic data for simple isocyanides that could provide a basis for their detection. Aims: Diisocyanomethane (CNCH2NC) is a small molecule with only seven atoms that is an interesting candidate for astrophysical detection. The rotational spectrum of diisocyanomethane has never been studied before, hence we present our analysis of its spectrum. Methods: We measured the rotational spectrum of diisocyanomethane in the frequency range 120-620 GHz using the Lille fast-scan and solid-state source spectrometers. The spectroscopic study was supported by high-level theoretical calculations of the molecular structure and both the harmonic and anharmonic force field. Results: The ground and the first excited vibrational state (ν15) are assigned and analysed. The dataset is composed of more than 2000 measured and fitted lines, which allows us to make accurate predictions of transition frequencies of diisocyanomethane in the frequency range up to 900 GHz. The statistical analysis of the results of the fit shows that the use of the S-reduction of the Watson rovibrational Hamiltonian for spectral modelling is more appropriate. Full Tables 2 and 3 are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/544/A82

  19. Multifractal spectrum of self-similar measures with overlap

    NASA Astrophysics Data System (ADS)

    Bruggeman, Cameron; Hare, Kathryn E.; Mak, Cheuk Yu

    2014-02-01

    It is well known that the multifractal spectrum of a self-similar measure satisfying the open set condition is a closed interval. Recently, there has been interest in the overlapping case and it is known that in this case there can be isolated points. We prove that for an interesting class of self-similar measures with overlap the spectrum consists of a closed interval union together with at most two isolated points. In the case of convolutions of uniform Cantor measures we determine the end points of the interval and the isolated points. We also give an example of a related self-similar measure where the spectrum is a union of two disjoint intervals. In contrast, we prove that if one considers quotient measures of this class on the quotient group [0, 1], rather than the real line, the multifractal spectrum is a closed interval.

  20. CASSIS: Interactive spectrum analyzer

    NASA Astrophysics Data System (ADS)

    Cassis Team At Cesr/Irap

    2014-02-01

    CASSIS (Centre d'Analyse Scientifique de Spectres Infrarouges et Submillimetriques), written in Java, is suited for broad-band spectral surveys to speed up the scientific analysis of high spectral resolution observations. It uses a local spectroscopic database made of the two molecular spectroscopic databases JPL and CDMS, as well as the atomic spectroscopic database NIST. Its tools include a LTE model and the RADEX model connected to the LAMDA molecular collisional database. CASSIS can build a line list fitting the various transitions of a given species and to directly produce rotational diagrams from these lists. CASSIS is fully integrated into HIPE, the Herschel Interactive Processing Environment, as a plug-in.