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Sample records for star rs cnc

  1. The Multi-Scale Environment of RS Cnc from CO and HI Observations

    NASA Astrophysics Data System (ADS)

    Hoai, D. T.; Matthews, L. D.; Winters, J. M.; Nhung, P. T.; Gérard, E.; Libert, Y.; Le Bertre, T.

    2015-08-01

    We present a detailed study of the circumstellar gas distribution and kinematics of the semi-regular variable star RS Cnc on spatial scales ranging from ˜1″ (˜150 AU) to ˜6' (˜0.24 pc). The close environment of RS Cnc (from 1 to 20″) can be described with a model in which the density and velocity vary smoothly from the equatorial plane to the polar axis. In this model the mass loss rate is higher along the polar directions than in the equatorial plane, which does not favor current models invoking stellar rotation or a magnetic field as the cause of the axi-symmetry. Outside this region, the study of which is limited by the photo-dissociation of CO, HI data at 21 cm show that the flow is slowed down at a typical distance of 1' (˜0.04 pc). Further away (1 to 6', or 0.04 to 0.24 pc), the flow is distorted by the relative motion of the star with respect to the interstellar medium.

  2. On the central symmetry of the circumstellar envelope of RS Cnc

    NASA Astrophysics Data System (ADS)

    Tuyet Nhung, Pham; Thi Hoai, Do; Winters, Jan Martin; Darriulat, Pierre; Gérard, Eric; Le Bertre, Thibaut

    2015-05-01

    We present a phenomenological study of CO(1-0) and CO(2-1) emission from the circumstellar envelope (CSE) of the Asymptotic Giant Branch (AGB) star RS Cnc. It reveals departures from central symmetry that turn out to be efficient tools for the exploration of some of the properties of the CSE. We use a wind model including a bipolar flow with a typical wind velocity of ~8 km s-1 that decreases to ~2 km s-1 near the equator. This wind model is used to describe Doppler velocity spectral maps obtained by merging data collected at the IRAM Plateau de Bure Interferometer and Pico Veleta single dish radio telescope. Parameters describing the wind morphology and kinematics are obtained, together with the radial dependence of the gas temperature in the domain of the CSE probed by the CO observations. Significant north-south central asymmetries are revealed by the analysis, which we quantify using a simple phenomenological description. The origin of such asymmetries is unclear. Based on observations carried out with the IRAM Plateau de Bure Interferometer and the IRAM 30 m telescope. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain).

  3. On the Central Symmetry of the Circumstellar Envelope of RS Cnc

    NASA Astrophysics Data System (ADS)

    Nhung, P. T.; Hoai, D. T.; Winters, J. M.; Darriulat, P.; Gérard, E.; Le Bertre, T.

    2015-08-01

    We present a phenomenological study of CO (1-0) and CO (2-1) emission from the circumstellar envelope (CSE) of the AGB star RS Cnc. It reveals departures from central symmetry that turn out to provide a new tool for the exploration of some of the CSE properties. We use a wind model including a bipolar flow with a typical wind velocity of ˜8 km s-1, decreasing to ˜2 km s-1 near the equator, to describe Doppler velocity spectral maps obtained by merging data collected at the IRAM Plateau de Bure Interferometer and the Pico Veleta single-dish radio telescope. Parameters describing the wind morphology and kinematics are obtained, together with the radial dependence of the gas temperature in the domain of the CSE probed by the CO observations. Significant north-south central asymmetries are revealed by the analysis, which we quantify using a simple phenomenological description. The origin of such asymmetries is unclear for the moment.

  4. RS CVn stars - Chromospheric phenomena

    NASA Technical Reports Server (NTRS)

    Bopp, B. W.

    1983-01-01

    The observational information regarding chromospheric emission features in surface-active RS CVn stars is reviewed. Three optical features are considered in detail: Ca II H and K, Balmer H-alpha and He I 10830 A. While the qualitative behavior of these lines is in accord with solar-analogy/rotation-activity ideas, the quantitative variation and scaling are very poorly understood. In many cases, the spectroscopic observations with sufficient SNR and resolution to decide these questions have simply not yet been made. The FK Com stars, in particular, present extreme examples of rotation that may well tax present understanding of surface activity to its limits.

  5. Line blanketed model atmospheres of Ap-stars. V - The Hg-Mn stars 53 Tau and Kappa CNC

    NASA Astrophysics Data System (ADS)

    Stepien, K.; Muthsam, H.

    1981-07-01

    All available observations of the energy distributions of 53 Tau and κ Cnc from the wavelength interval between Lα and the Paschen jump are compared with a series of model atmospheres in which temperature, microturbulent velocity and chemical composition were varied. Good agreement is obtained if effective temperatures of 53 Tau and κ Cnc are 11,250 K and 12,800 K, respectively, and the chemical compositions are taken from Strom (1969) and Kodaira (1965). New chemical compositions obtained by Heacox (1979) produce too much blanketing in UV, particularly for κ Cnc. For 53 Tau the set with υmicr = 0 gives equally good fit as the old abundances and the resulting temperature is 11,400 K. Observations of both stars show a slight excess of radiation in the red. It is suggested that this excess may be caused by the circumstellar matter.

  6. Infrared observations of RS CVn stars

    NASA Technical Reports Server (NTRS)

    Berriman, G.; De Campli, W. M.; Werner, M. W.; Hatchett, S. P.

    1983-01-01

    The paper presents infrared photometry of the RS CVn binary stars AR Lac (1.2-10 microns) and MM Her (1.2-3.5 microns) as they egressed from their primary and secondary eclipses; of the eclipsing systems RS CVn and Z Her at maximum light (1.2-10 microns) and of the non-eclipsing systems UX Ari and HR 1099 (1.2-10 microns). An analysis of these and published V data based on flux ratio diagrams (linear analogues of color-color diagrams) shows that G and K stars supply the infrared light of these systems. In AR Lac, the combined light of a G5-K0 subgiant and either a late F dwarf or an early F subgiant can account for the observed visual and infrared light curves. None of these systems shows infrared emission from circumstellar matter. This result is simply understood: dust grains would not be expected to form in the physical conditions surrounding the subgiant, and the corona and chromosphere (whose properties have been deduced from spectroscopic X-ray observations) should not produce appreciable infrared emission.

  7. Theoretical studies of the RS Canum Venaticorum stars

    NASA Technical Reports Server (NTRS)

    Mullan, D. J.

    1982-01-01

    The activity in RS Canum Venaticorum (CVn) is investigated. Models for chromospheric structure are developed and the role of magnetic fields both in the photosphere as well as in the chromosphere and upper atmosphere are examined. T Tau stars are also studied from the same points of view. The properties of magnetic field loops are used to help understand the atmospheric structure in RS CVn stars. The concepts developed in the case of these stars appear to be applicable over a much broader region of the HR diagram. The absence of stable magnetic loops in the atmospheres of late type giant stars suggests that the atmospheres of RS CVn active components are qualitatively distinct from the solar atmosphere.

  8. MOA-2010-BLG-523: 'FAILED PLANET' = RS CVn STAR

    SciTech Connect

    Gould, A.; Yee, J. C.; Pinsonneault, M. H.; Dong, Subo; Gaudi, B. S.; Hung, L.-W.; Bond, I. A.; Udalski, A.; Han, C.; Jorgensen, U. G.; Greenhill, J.; Tsapras, Y.; Bensby, T.; Allen, W.; Almeida, L. A.; Jablonski, F.; Bos, M.; Christie, G. W.; DePoy, D. L.; Lee, C.-U.; Collaboration: muFUN Collaboration; MOA Collaboration; OGLE Collaboration; MiNDSTEp Consortium; RoboNet Collaboration; PLANET Collaboration; and others

    2013-02-15

    The Galactic bulge source MOA-2010-BLG-523S exhibited short-term deviations from a standard microlensing light curve near the peak of an A {sub max} {approx} 265 high-magnification microlensing event. The deviations originally seemed consistent with expectations for a planetary companion to the principal lens. We combine long-term photometric monitoring with a previously published high-resolution spectrum taken near peak to demonstrate that this is an RS CVn variable, so that planetary microlensing is not required to explain the light-curve deviations. This is the first spectroscopically confirmed RS CVn star discovered in the Galactic bulge.

  9. Long-term spottedness variations of 16 RS CVn stars

    NASA Astrophysics Data System (ADS)

    Kozhevnikova, A. V.; Alekseev, I. Yu.

    2015-10-01

    An improved zonal model for spotted stellar photospheres enabling analysis of two active longitudes simultaneously present on a star is used to determine the spottedness parameters for a sample of chromospherically active RS CVn binary stars. Variations of the spot-activity characteristics of these systems with time are analyzed for time scales of several decades, in order to search for evolutionary changes of their spotted regions. The analysis made use of observations acquired during multi-color photometric monitoring of six spotted active RS CVn systems conducted at the Astronomical Observatory of the Ural Federal University and the Crimean Astrophysical Observatory since 2003, as well as data from the literature. Half of the stars display drifts of their spots towards the equator and poles during some time intervals; however, the speeds of the spots' latitude drifts are lower than the analogous speeds for sunspots, by factors of 1.5-4, on average. Correlations or anti-correlations between a spot's area and its latitude were detected for nine stars, with the correlation coefficients R ranging from 0.54 to 0.93; stronger correlations are found for stars whose spot areas increasewith increasing latitude during the entire analyzed time interval. Activity cycles lasting from 5 to 28 years have been determined or confirmed for nine of the studied systems.

  10. Quiescent and Flaring Structure in RS Canum Venaticorum Stars

    NASA Astrophysics Data System (ADS)

    Sanz-Forcada, J.; Brickhouse, N. S.; Dupree, A. K.

    2002-05-01

    Four of the most active RS CVn stars (V711 Tau, II Peg, σ Gem, and UX Ari) have been observed for a total of 3 Ms with the Extreme Ultraviolet Explorer satellite (EUVE) between 1992 and 2000 January. Flaring and quiescent states of extreme ultraviolet spectra (λλ70-740) and light curves (λλ75-175) have been analyzed to provide emission measure distributions (EMD) for these systems in the range logTe(K)~5.6-7.4, based principally on iron lines. Flux measurements obtained with IUE and the Orbiting and Retrievable Far and Extreme Ultraviolet Spectrometer (ORFEUS) complete the EMD in the lower temperature range [logTe(K)~4.0-5.6]. Frequent flaring activity has been found in the systems, including an increase during the rise phase by a factor of ~9 in the flux of σ Gem, the largest flare enhancement observed with EUVE. Analyses of the EUVE emission in the active single star AB Dor and the low-rotation giant star β Cet are also included. The EMDs are remarkably similar among all the stars, showing a narrow enhancement or ``bump'' around logTe(K)~6.9. These narrow bumps are apparently unrelated to rotation rate, spectral type, binarity, or evolutionary stage. Significant material is found at logTe(K)>~7.0 for the most active stars. Modulation of the EUV flux outside of flaring occurs in four of the stars (σ Gem, V711 Tau, UX Ari, AB Dor). The electron density ranges between Ne~1012 and ~1013 cm-3, measured at logTe(K)~7.0, and may reach higher values during flares. These densities and EMD values imply small scale sizes for emitting regions.

  11. Magnetic field topology of the RS CVn star II Pegasi

    NASA Astrophysics Data System (ADS)

    Kochukhov, O.; Mantere, M. J.; Hackman, T.; Ilyin, I.

    2013-02-01

    Context. The dynamo processes in cool active stars generate complex magnetic fields responsible for prominent surface stellar activity and variability at different time scales. For a small number of cool stars magnetic field topologies were reconstructed from the time series of spectropolarimetric observations using the Zeeman Doppler imaging (ZDI) method, often yielding surprising and controversial results. Aims: In this study we follow a long-term evolution of the magnetic field topology of the RS CVn binary star II Peg using a more self-consistent and physically more meaningful modelling approach compared to previous ZDI studies. Methods: We collected high-resolution circular polarisation observations of II Peg using the SOFIN spectropolarimeter at the Nordic Optical Telescope. These data cover 12 epochs spread over 7 years, comprising one of the most comprehensive spectropolarimetric data sets acquired for a cool active star. A multi-line diagnostic technique in combination with a new ZDI code is applied to interpret these observations. Results: We have succeeded in detecting clear magnetic field signatures in average Stokes V profiles for all 12 data sets. These profiles typically have complex shapes and amplitudes of ~10-3 of the unpolarised continuum, corresponding to mean longitudinal fields of 50-100 G. Magnetic inversions using these data reveals evolving magnetic fields with typical local strengths of 0.5-1.0 kG and complex topologies. Despite using a self-consistent magnetic and temperature mapping technique, we do not find a clear correlation between magnetic and temperature features in the ZDI maps. Neither do we confirm the presence of persistent azimuthal field rings found in other RS CVn stars. Reconstruction of the magnetic field topology of II Peg reveals significant evolution of both the surface magnetic field structure and the extended magnetospheric field geometry on the time scale covered by our observations. From 2004 to 2010 the total field energy drastically declined and the field became less axisymmetric. This also coincided with the transition from predominantly poloidal to mainly toroidal field topology. Conclusions: A qualitative comparison of the ZDI maps of II Peg with the prediction of dynamo theory suggests that the magnetic field in this star is produced mainly by the turbulent ?2 dynamo rather than the solar ?? dynamo. Our results do not show a clear active longitude system, nor is there evidence of the presence of an azimuthal dynamo wave. Based on observations obtained with the Nordic Optical Telescope, operated on the island of La Palma jointly by Denmark, Finland, Iceland, Norway, and Sweden, at the Spanish Observatorio del Roque de los Muchachos of the Instituto Astrofisica de Canarias.

  12. Possible magnetic activity cycles in two solar-type overcontact binary stars: AD Cnc and FG Hya

    NASA Astrophysics Data System (ADS)

    Qian, S.-B.; Soonthornthum, B.; Yuan, J.-Z.; He, J.-J.; Zhu, L. Y.

    2006-08-01

    W UMa-type binary stars are overcontact systems where both components are filling the critical Roche lobes and sharing a common convictive envelope (CCE). This type of binaries offers a good chance to study the effects of the CCE on solar-type magnetic activity. Recently, two solar-type overcontact binaries, AD Cnc (Sp.=K0; P=0.2827 days) and FG Hya (Sp.=G0; P=0.3278 days), have been monitored for several years photometrically with the 1.0-m telescope in Yunnan Observatory. The light levels at both minima and both maxima in the light curves were found to be variable. An orbital period analysis of the two systems were done based on our new determined times of light minimum combined with the others compiled from the literature. After long-term period changes were removed, double cyclic period changes were discovered for the two binaries. The light curves of those sample stars have been analysed with the new version of the W-D method and the properties of dark spot on the photospheric surface were determined. The main results are as following. (1) For FG Hya, we found that both the orbital period and the depth of the primary minimum show a cyclic change with a period of 36.4 years and in the same phase. The variation of the light curve, the spotted primary component and the connection between the period change and the depth of the primary minimum all indicate that the G0-type primary component display solar-type magnetic activity cycle with a period of 36.4 years. (2) The long-term evolution of dark spot on the photospheric surface of the primary component is presented based on the analysis of the variation of the light curves. It is found that the dark spot activity may have a 17-year cycle, which is close to the period of one cyclic component of the period variations (16.2 years). This suggests that the primary component (K0-type star) may have a 17-year magnetic activity cycle.

  13. The Motion Verified Red Stars (MoVeRS) Catalog and Low-Mass Field Stars with Warm Dust

    NASA Astrophysics Data System (ADS)

    Theissen, Christopher; West, Andrew A.; Dhital, Saurav

    2016-01-01

    We present the Motion Verified Red Stars (MoVeRS) catalog of proper motion selected low-mass stars from SDSS, 2MASS, and WISE. These surveys provide a time baseline of ~12 years for sources found in all three surveys, and a precision better than 10 mas/year.The MoVeRS catalog is augmented with proper motions from SDSS+USNO-B and the full sample contains 8,735,004 photometric point-sources selected based on colors and their significant (2σ) proper motions. This catalog will be useful for finding new low-mass common proper motion systems, along with providing a large input catalog for numerous studies of low-mass stars. In addition, we use the MoVeRS catalog to present a preliminary sample of low-mass field stars exhibiting signatures of warm dust (mid-infrared excesses). Such systems are thought to originate from collisions of terrestrial planets, raising even more questions about the habitability of planetary systems around low-mass stars.

  14. High-resolution Infrared Spectroscopy of Starspots on RS CVn Stars

    NASA Astrophysics Data System (ADS)

    O'Neal, D.; Neff, J. E.; Saar, S. H.

    1997-12-01

    We present results from a study of magnetically active stars using the PHOENIX infrared spectrograph at KPNO. We constrain starspot coverages on RS CVn stars using high-resolution observations of two temperature-sensitive OH lines near 1.563mu m (6397 cm(-1) ). The use of these features holds two advantages over the TiO bands that we have used previously: the OH lines are visible in spots up to ~ 4500 K; and spots are much brighter, relative to the unspotted photosphere, in the infrared than in the visible. These properties also make these OH lines excellent candidates for the first Doppler imaging study to use high-resolution observations of infrared spectral features. Using the OH lines, we also search for previously unknown secondary stars in ``single-lined'' RS CVn binary systems, including II Pegasi (HD 224085).

  15. VizieR Online Data Catalog: Motion Verified Red Stars (MoVeRS) (Theissen+, 2016)

    NASA Astrophysics Data System (ADS)

    Theissen, C. A.; West, A. A.; Dhital, S.

    2015-09-01

    We present a photometric catalog of 8,735,004 proper motion selected low-mass stars (KML-spectral types) within the Sloan Digital Sky Survey (SDSS) footprint, from the combined SDSS-DR10, Two-Micron All-Sky Survey (2MASS) Point Source Catalog (PSC), and Wide-field Infrared Survey Explorer (WISE) AllWISE catalog. Stars were selected using r-i, i-z, r-z, z-J, and z-W1 colors, and SDSS, WISE, and 2MASS astrometry was combined to compute proper motions. The resulting 3,518,150 stars were augmented with proper motions for 5,216,854 earlier type stars from the combined SDSS and United States Naval Observatory B1.0 catalog (USNO-B). We used SDSS+USNO-B proper motions to determine the best criteria for selecting a clean sample of stars. Only stars whose proper motions were greater than their 2-sigma uncertainty were included. Our Motion Verified Red Stars (MoVeRS) catalog is available through SDSS CasJobs and VizieR. (2 data files).

  16. Very Short-Duration UV-B Optical Flares in RS CVn-type Star Systems

    NASA Astrophysics Data System (ADS)

    Vander Haagen, G. A.

    2013-06-01

    Very short duration UV-B optical flares were observed during a high-cadence search for conventional flares on three RS CVn type stars: AR Lac, II Peg, and UX Ari. A statistical criterion was developed for isolating these short-duration optical flares from random photon events. Five flares, ranging in duration from 30 to 85 ms with peaks 0.29-0.51 mag. above the mean, were detected within the 132 hours of monitoring time. The time resolution of the observations was 5 ms for AR Lac and 10 ms for II Peg and UX Ari.

  17. Southern RS CVn systems - Candidate list. [spectral catalog of variable binary stars

    NASA Technical Reports Server (NTRS)

    Weiler, E. J.; Stencel, R. E.

    1979-01-01

    A list of 43 candidate RS CVn binary systems in the far southern hemisphere of the sky (south of -40 deg declination) is presented. The candidate systems were selected from the first two volumes of the Michigan Spectral Catalog (1975, 1978), which provides MK classifications for southern HD stars and identifies any unusual characteristics noted for individual stellar spectra. The selection criteria used were: (1) the occurrence of Ca II H and K emission; (2) known or suspected binary nature; (3) regular light variations of zero to one magnitude; and (4) spectral type between F0 and K2 and luminosity less than bright giant (II).

  18. HE 0017+0055: A probable pulsating CEMP-rs star and long-period binary

    NASA Astrophysics Data System (ADS)

    Jorissen, A.; Hansen, T.; Van Eck, S.; Andersen, J.; Nordström, B.; Siess, L.; Torres, G.; Masseron, T.; Van Winckel, H.

    2016-02-01

    Context. A large fraction of the carbon-enhanced, extremely metal-poor halo giants ([Fe/H] < -2.5) are also strongly enriched in neutron-capture elements from the s process (CEMP-s stars). The conventional explanation for the properties of these stars is mass transfer from a nearby binary companion on the asymptotic giant branch (AGB). This scenario leads to a number of testable predictions in terms of the properties of the putative binary system and the resulting abundance pattern. Among the CEMP stars, some stars further exhibit overabundances in r-process elements on top of the s-process enrichment, and are tagged CEMP-rs stars. Although the nucleosynthesis process responsible for this kind of mixed abundance pattern is still under debate, CEMP-rs stars seem to belong to binary systems as do CEMP-s stars. Aims: Our aim is to present and analyse in detail our comprehensive data set of systematic radial-velocity measurements and high-resolution spectroscopy of the CEMP star HE 0017+0055. Methods: Our precise radial-velocity monitoring of HE 0017+0055 over 2940 days (8 yr) with the Nordic Optical Telescope and Mercator telescopes exhibits variability, with a period of 384 d and amplitude of 540 ± 27 m s-1 superimposed on a nearly linear long-term decline of ~1 m s-1 day-1. We used high-resolution HERMES/Mercator and Keck/HIRES spectra to derive elemental abundances with 1D LTE MARCS models. A metallicity of [Fe/H] ~ -2.4 is found, along with s-process overabundances of the order of 2 dex (with the exception of [Y/Fe] ~ + 0.5), and most notably overabundances of r-process elements like Sm, Eu, Dy, and Er in the range 0.9-2.0 dex. With [Ba/Fe] > 1.9 dex and [Eu/Fe] = 2.3 dex, HE 0017+0055 is a CEMP-rs star. We used the derived atmospheric parameters and abundances to infer HE 0017+0055 evolutionary status from a comparison with evolutionary tracks. Results: HE 0017+0055 appears to be a giant star below the tip of the red giant branch. The s-process pollution must therefore originate from mass transfer from a companion formerly on the AGB, which is now a carbon-oxygen white dwarf (WD). If the 384 d velocity variations are attributed to the WD companion, its orbit must be seen almost face-on, with i ~ 2.3°, because the mass function is very small: f(M1,M2) = (6.1 ± 1.1) × 10-6M⊙. Alternatively, the WD orbital motion could be responsible for the long-term velocity variations, with a period of several decades. The 384 d variations should then be attributed either to a low-mass inner companion (perhaps a brown dwarf, depending on the orbital inclination), or to stellar pulsations. The latter possibility is made likely by the fact that similar low-amplitude velocity variations, with periods close to 1 yr, have been reported for other CEMP stars in a companion paper. A definite conclusion about the origin of the 384 d velocity variations should however await the detection of synchronous low-amplitude photometric variations. Based on observations performed with the Mercator telescope and the Nordic Optical Telescope (NOT), operated by the Nordic Optical Telescope Scientific Association at the Roque de los Muchachos Observatory, La Palma, Spain, of the Instituto de Astrofïsica de Canarias.

  19. CNC Programming I.

    ERIC Educational Resources Information Center

    Casey, Joe

    This document contains five units for a course in computer numerical control (CNC) for computer-aided manufacturing. It is intended to familiarize students with the principles and techniques necessary to create proper CNC programs manually. Each unit consists of an introduction, instructional objectives, learning materials, learning activities,…

  20. Open architecture CNC system

    SciTech Connect

    Tal, J.; Lopez, A.; Edwards, J.M.

    1995-04-01

    In this paper, an alternative solution to the traditional CNC machine tool controller has been introduced. Software and hardware modules have been described and their incorporation in a CNC control system has been outlined. This type of CNC machine tool controller demonstrates that technology is accessible and can be readily implemented into an open architecture machine tool controller. Benefit to the user is greater controller flexibility, while being economically achievable. PC based, motion as well as non-motion features will provide flexibility through a Windows environment. Up-grading this type of controller system through software revisions will keep the machine tool in a competitive state with minimal effort. Software and hardware modules are mass produced permitting competitive procurement and incorporation. Open architecture CNC systems provide diagnostics thus enhancing maintainability, and machine tool up-time. A major concern of traditional CNC systems has been operator training time. Training time can be greatly minimized by making use of Windows environment features.

  1. Elemental abundance analyses with Coudé Echelle spectrograms from the TÜBİTAK National Observatory of Turkey: I. The HgMn stars 11 Per, HR 2801, and ν Cnc

    NASA Astrophysics Data System (ADS)

    Adelman, S. J.; Yüce, K.

    2010-08-01

    Using coadded spectrograms taken with the Coudé Echelle Spectrograph (CES) of the 1.50-m Russian-Turkish Telescope of the TÜBİTAK National Observatory (TUG) near Antalya in Turkey, elemental abundance analyses of three HgMn stars 11 Per, HR 2801, and ν Cnc were performed. Comparisons are made with spectra obtained with the long camera of the Dominion Astrophysical Observatory (DAO) coudé spectrograph and its SITe4 CCD. The CES equivalent widths are about 12% larger than that for the DAO long camera. Our first results from TUG data/spectra show that all three stars exhibit the Hg II λ3984 line and somewhat diverse abundance patterns. 11 Per tends to have underabundant light elements with underabundant and overabundant Fe-peak elements. HR 2801 has mostly underabundant elements, with a few elements having solar abundances while N and Mn are overabundant. The coolest star ν Cnc has light elements having mostly solar abundances, overabundant iron group abundances, and very overabundant SrYZr and Ba. Comparisons with the abundance patterns of other HgMn stars show that they have a wide diversity of abundance patterns. Tables 2 and 6 are available at the CDS via http://cdsarc.u-strasbg.fr/cgi-bin/qcat?J/AN/331/785.

  2. The dusty AGB star RS CrB: first mid-infrared interferometric observations with the Keck telescopes

    NASA Technical Reports Server (NTRS)

    Mennesson, B.; Koresko, C.; Creech-Eakman, M. J.; Serabyn, E.; Colavita, M. M; Akeson, R.; Appleby, E.; Bell, J.; Booth, A.; Crawford, S.; Dahl, W.; Fanson, J.; Felizardo, C.; Garcia, J.; Gathright, J.; Herstein, J.; Hovland, E.; Hrynevych, M.; Johansson, E.; Le Mignant, D.; Ligon, R.; Millan-Gabet, R.; Moore, J.; Neyman, C.; Palmer, D.

    2005-01-01

    We report interferometric observations of the semiregular variable star RS CrB, a red giant with strong silicate emission features. The data were among the first long-baseline mid-infrared stellar fringes obtained between the Keck telescopes, using parts of the new nulling beam combiner.

  3. CAD/CAM/CNC.

    ERIC Educational Resources Information Center

    Domermuth, Dave; And Others

    1996-01-01

    Includes "Quick Start CNC (computer numerical control) with a Vacuum Filter and Laminated Plastic" (Domermuth); "School and Industry Cooperate for Mutual Benefit" (Buckler); and "CAD (computer-assisted drafting) Careers--What Professionals Have to Say" (Skinner). (JOW)

  4. Rotational modulation and flares on RS CVn and BY Dra stars. IV - The spatially resolved chromosphere of AR Lacertae

    NASA Technical Reports Server (NTRS)

    Walter, F. M.; Neff, J. E.; Linsky, J. L.; Gibson, D. M.; Rodono, M.

    1987-01-01

    The authors observed the RS Canum Venaticorum system AR Lacertae systematically over an orbital period with the International Ultraviolet Explorer in October 1983. Contemporaneous radio observations were obtained at the VLA. The spectra of the Mg II k emission line were analyzed using a Doppler imaging technique. In this way, three discrete regions of emission were identified in the outer atmosphere of the K star-two 'plages' and a chromospheric brightening that was related to a radio flare. The widths of the plage profiles indicate that the two plages together cover about 2 percent of the visible stellar hemisphere, and their v sin i values indicate that they lie close to the equator of the K star. The Mg II k surface flux in the plages is about five times the mean Mg II k surface flux of the K star.

  5. Multiple wavelength microwave observations of the RS Canum Venaticorum stars UX Arietis, HR 1099, HR 5110, and II Pegasi

    NASA Astrophysics Data System (ADS)

    Willson, Robert F.; Lang, Kenneth R.

    1987-01-01

    The VLA was used to observe the RS CVn stars, UX Arietis, HR 1099, HR 5110, and II Pegasi with a time resolution of 6.6 s at two pairs of wavelengths near 4835 MHz and 1415 MHz. Variable emission was detected from UX Arietis at 4835 MHz on time scales ranging from 30 s to more than 1 hr. From the variations an upper limit to the source size of L ≤ 9×1011cm is derived. The authors also derive a magnetic field of H ≤ 15 G for the varying source and show that the time scale of the variations cannot be due to synchrotron radiation losses. Instead it is suggested that the variations may be due to absorption by a thermal plasma located between the stars of the binary system.

  6. Vitesses radiales photoélectriques de binaires àéclipses. VI. Orbites spectroscopiques et éléments physiques de 12 étoiles doubles Photoelectric radial velocities of eclipsing binaries VI. Orbital and physical elements of 12 double stars

    NASA Astrophysics Data System (ADS)

    Imbert, M.

    2002-06-01

    Spectroscopic orbits of the 12 eclipsing binary systems, TW And, CD And, RS Ari, RU Cnc, TW Cnc, UU Cnc, V788 Cyg, AW Her, MM Her, RV Lib, EW Ori and ZZ UMa are obtained from Coravel and Elodie radial velocity measurements. We obtain a first orbit for CD And, RS Ari, TW Cnc, and V788 Cyg. For the systems TW And, RU Cnc, UU Cnc, AW Her, MM Her, RV Lib, EW Ori and ZZ UMa, the new spectroscopic orbits are either better or of quality comparable to that previously published. The physical properties of these systems were estimated with the photometric parameters from available data except CD And, TW Cnc, UU Cnc, V788 Cyg and RV Lib for which we found a model compatible with the observations. The systems RU Cnc, AW Her, MM Her and RV Lib belong to RS CVn group. In general these systems were difficult to observe with Coravel, on the one hand because the stars are relatively weak and on the other hand because of nature of the components giving peaks of correlation with weak contrast. La plupart des observations ont été effectuées àl'Observatoire de Haute-Provence (CNRS). Based, in part, on observations collected at the European Southern Observatory, la Silla, Chile. La Table 1 est disponible seulement sous forme électronique au CDS via ftp à cdsarc.u-strasbg.fr (130.79.128.5) ou via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/387/850

  7. Multiple wavelength microwave observations of the RS Canum Venaticorum stars UX Arietis, HR 1099, HR 5110, and II Pegasi

    SciTech Connect

    Willson, R.F.; Lang, K.R.

    1987-01-01

    The variabilities, core size and magnetic field of the RS CVn star UX Arietis was measured with the VLA at pairs of frequencies near 1415 MHz and 4835 MHz on June 10, 1985. Data were also gathered on HR 1099, HR 5110 and II Peg. UX Arietis exhibited variability on time scales ranging from 30 sec to 1 hr at 4835 MHz, but no detectable variations at 1415 MHz. An upper limit of 900 billion cm was placed on the size of the core emitting region, which is estimated to have a magnetic field strength of 15 G. The 30 sec variations are attributed to absorption by thermal plasma between the G5 and K1 companions of the UX Arietis system. 37 references.

  8. Multiple wavelength microwave observations of the RS Canum Venaticorum stars UX Arietis, HR 1099, HR 5110, and II Pegasi

    NASA Technical Reports Server (NTRS)

    Willson, Robert F.; Lang, Kenneth R.

    1987-01-01

    The variabilities, core size and magnetic field of the RS CVn star UX Arietis was measured with the VLA at pairs of frequencies near 1415 MHz and 4835 MHz on June 10, 1985. Data were also gathered on HR 1099, HR 5110 and II Peg. UX Arietis exhibited variability on time scales ranging from 30 sec to 1 hr at 4835 MHz, but no detectable variations at 1415 MHz. An upper limit of 900 billion cm was placed on the size of the core emitting region, which is estimated to have a magnetic field strength of 15 G. The 30 sec variations are attributed to absorption by thermal plasma between the G5 and K1 companions of the UX Arietis system.

  9. On the coronae of rapidly rotating stars. I - The relation between rotation and coronal activity in RS CVn systems

    NASA Technical Reports Server (NTRS)

    Walter, F. M.; Bowyer, S.

    1981-01-01

    Soft X-ray observations are presented of a nearly complete sample of RS Canum Venaticorum systems taken with the Einstein X-ray Observatory. It is shown that the quiescent coronal activity, as measured by the ratio of the X-ray to bolometric flux, is directly proportional to the angular velocity of the star with the active chromosphere in these systems. This relation is found to hold over two decades in angular velocity. It is also found that the stellar surface gravity has no obvious influence on the ratio of the X-ray luminosity to the bolometric luminosity over two decades in surface gravity. It is pointed out that the linear relation between the ratio of the X-ray luminosity to the bolometric luminosity on the one hand, and the angular velocity, on the other, holds important implications for dynamo theories of the generation of stellar magnetic fields.

  10. Title: MAXI/GSC detected an intense X-ray flare from an RS CVn star VY Ari

    NASA Astrophysics Data System (ADS)

    Nakamura, Y.; Sasaki, R.; Tsuboi, Y.; Negoro, H.; Ueno, S.; Tomida, H.; Nakahira, S.; Ishikawa, M.; Nakagawa, Y. E.; Sugawara, Y.; Mihara, T.; Sugizaki, M.; Serino, M.; Iwakiri, W.; Shidatsu, M.; Sugimoto, J.; Takagi, T.; Matsuoka, M.; Kawai, N.; Isobe, N.; Sugita, S.; Yoshii, T.; Tachibana, Y.; Ono, Y.; Fujiwara, T.; Yoshida, A.; Sakamoto, T.; Kawakubo, Y.; Kitaoka, Y.; Tsunemi, H.; Shomura, R.; Nakajima, M.; Tanaka, K.; Masumitsu, T.; Kawase, T.; Ueda, Y.; Kawamuro, T.; Hori, T.; Tanimoto, A.; Yamauchi, M.; Furuya, K.; Yamaoka, K.

    2016-05-01

    On May 12 2016, the MAXI/GSC detected an enhanced X-ray emission at a position consistent with that of an RS CVn star VY Ari. The flux peak was observed at a transit starting at 12:34 UT on 11 May 2016 with a value of 146+-35 mCrab (90% error) in the 4-10 keV band, corresponding to a luminosity of 5 & times1032 ergs/s for an assumed distance of 44 pc. At the next scan starting at 14:08 on 11 May 2016, the observed flux was 83+-26 mCrab (90% error) in the 4-10 keV, corresponding to a luminosity of 4 & times1032 ergs/s.

  11. Rotational modulation and flares on RS CVn and BY Dra stars

    NASA Technical Reports Server (NTRS)

    Andrews, A. D.; Butler, C. J.; Rodono, M.; Linsky, J. L.; Brown, A.

    1988-01-01

    Evidence is presented for spots, plages, and flares on the noneclipsing RS CVn system II Peg and V 711 Tau. The large spot originally found on II Peg in 1981.8 could still be identified in 1983. Two spectroscopic flares of II Peg were detected. For the larger flare the fluxes in the strongest transition-region lines reached about six times their quiescent values. A comparison of the 1981 and 1983 flux variations show that active regions or plages are located on one hemisphere. On V 711 Tau at least two flares were observed. Outside of these flares, the strongest chromospheric and transition-region emission lines exhibited weak phase-dependent variations that persist over 173 orbital cycles (1981-1983) and are possibly associated with one of the proposed spots. For both stellar systems the fluxes from the higher temperature emission lines showed the greatest variations.

  12. Doppler Imagery of the Spotted RS Canum Venaticorum Star HR 1099 (V711 Tauri) from 1981 to 1992

    NASA Astrophysics Data System (ADS)

    Vogt, Steven S.; Hatzes, Artie P.; Misch, Anthony A.; Krster, M.

    1999-04-01

    We present a set of 23 Doppler images of the spotted RS CVn star HR 1099 (V711 Tauri; HD 22468) obtained from 1981 to 1992. HR 1099 shows a large, cool polar spot that has persisted for the 11 yr of this study and other low-latitude spots that come and go on relatively short (less than 1 yr) timescales and can emerge anywhere on the star. The polar spot has variable protuberances that look very similar to the time-variable vertical extensions of the Sun's polar coronal hole. The area of the polar spot and its extensions shows marginal evidence of being variable, with a period of about 3 yr and an amplitude of about 1% that is perhaps indicative of a weak cycle, but this is not yet conclusive. Comparison of our Doppler images with previously published ``few spot'' model fits to the light curves shows that such simple spot-model solutions, while sometimes in agreement, are often misleading and nonunique, particularly when the light-curve amplitude is small. Moreover, these spot-model fits do not recover the existence of the polar spot. The Doppler images show quite good agreement among multiple images at a given epoch and between different Doppler imaging research groups using completely independent data sets and imaging software. Our (cool spots only) Doppler imaging solutions, when properly thresholded, generally well reproduce the published light curves. However, in one instance the difficulty of fitting light curves suggests that at least one hot spot was present on HR 1099 during one observing season. Variations in the mean brightness of the system at the observed 0.05 mag level seem to correlate with spot area, particularly the polar spot, indicating that the mean light level is a pretty good proxy of spot area on HR 1099. While the polar spot with variable extensions was always present, isolated spots also frequently appeared at both mid- and low latitudes. On several occasions isolated prominent spots emerged and then disappeared on or near the equator. The ``migrating photometric wave'' on HR 1099 is due not to a simple longitudinal migration of spots on a differentially rotating star but rather to changes in the spatial distribution of a few spots (some of which move but most of which are fixed in longitude) that emerge and then disappear. So, at least for HR 1099, the phase drift of this migrating photometric wave minimum contains very little unique information about differential rotation or spot migration. While the tracking of individual features involves some uncertainty and speculation because of our limited time sampling, the tracks of two long-lived spots suggest that some spots that emerge at low or intermediate latitudes may migrate up to the pole in a clockwise spiral (slower than the orbit), then apparently merge with the polar spot. If these dark spots trace magnetic flux, we speculate that some of the magnetic flux emerging at lower latitudes migrates poleward and merges with the polar spot flux. It is not yet clear whether this flux is of the same or opposite polarity to the polar spot and thus whether these poleward-migrating, low-latitude spots reinforce or cancel the polar spot field. One of the high-latitude spots also appeared to get stretched in longitude as it approached the polar spot, and its overall track is quite reminiscent of the annulus of toroidal field found by Donati et al. encircling the polar spot of HR 1099 in 1990.9. In general, the spots appear to be very tightly locked to the orbital frame of the system, and most disappear before they have had a chance to migrate significantly. Like solar coronal holes, they show very little evidence for shear due to differential rotation. A few selected, long-lived features gave longitudinal migration rates of 1 part in 300 to 1 part in 3600 of the rotation period, in the sense that intermediate and low latitudes rotate slightly slower than the orbital angular velocity, while the pole and highest latitudes appear to be synchronized to the orbit. The implied differential rotation is thus of opposite sign and about a factor of 56 less than for the Sun. The rotation rate versus latitude behavior can be well fitted with a variety of formulae, including the Maunder formula. One of the best fits is provided by a rotation period versus latitude that is proportional to the surface strength of a centered axisymmetric magnetic dipole field, with the pole synchronized to the orbit and lower latitudes rotating more slowly. We believe that these starspots are not measuring photospheric differential rotation. Instead, like solar coronal holes, their relatively low degree of shearing and nearly solid body rotation may be enforced by a multikilogauss, axisymmetric, nearly current-free quasi-potential global magnetic field. Our Doppler images also agree very closely with the Zeeman-Doppler imagery of Donati et al. and support their finding that regions around the edge of the polar spot and within bright spots show largely monopolar fields of at least 300-700 G strength. The large, permanent cool polar spots, the very low observable differential rotation and shearing of starspots, and the evidence of strong, essentially unipolar magnetic fields associated with them leads us to believe that HR 1099 and other rapidly rotating RS CVn stars harbor quite strong (multikilogauss) axisymmetric global magnetic dipole fields. These fields have historically been largely hidden from view by their high degree of rotational symmetry, by being concentrated in the low surface brightness dark spots, and by these stars' high degree of rotational line broadening. We propose that the starspots on HR 1099 and other rapidly rotating RS CVn stars are, by analogy with solar coronal holes, large unipolar, magnetic regions that are tightly frozen into multikilogauss, axisymmetric global dipole fields in these stars. Since the large cool polar spots, the signature of these dipoles, are not present on more slowly rotating RS CVn stars, we believe that they must be dynamo-induced fields rather than remnant fossil fields. Based on observations collected at UCO/Lick Observatory, McDonald Observatory, and the European Southern Observatory.

  13. Degraded RNA transcript stable regions (StaRs) as targets for enhanced forensic RNA body fluid identification.

    PubMed

    Lin, Meng-Han; Albani, Patricia P; Fleming, Rachel

    2016-01-01

    The detection of messenger RNA (mRNA) using reverse transcriptase PCR (RT-PCR) is becoming common practice for forensic body fluid identification. However, the degraded and scarce nature of RNA from forensic samples mean that mRNA transcripts are not consistently detected or remain undetected in practice. Conventional primer design for RT-PCR (and quantitative RT-PCR) includes targeting primers to span exon-exon boundaries or by having the primers on two separate exons, and satisfying common primer thermodynamic criteria. We have found that the conventional placement of primers is not always optimal for obtaining reproducible results from degraded samples. Using massively parallel sequencing data from degraded body fluids, we designed primers to amplify transcript regions of high read coverage, hence, higher stability, and compared these with primers designed using conventional methodology. Our findings are that primers designed for transcript regions of higher read coverage resulted in vastly improved detection of mRNA transcripts that were not previously detected or were not consistently detected in the same samples using conventional primers. We developed a new concept whereby primers targeted to transcript stable regions (StaRs) are able to consistently and specifically amplify a wide range of RNA biomarkers in various body fluids of varying degradation levels. PMID:26485676

  14. CNC Preparation Meets Manufacturing Opportunity

    ERIC Educational Resources Information Center

    Cassola, Joel

    2006-01-01

    This article features the machining technology program at Cape Fear Community College (CFCC) of Wilmington, North Carolina. North Carolina's Cape Fear Community College is working to meet diverse industry needs through its CNC training. The school's program has gained the attention of the local manufacturing community and students when it shifted…

  15. Far-ultraviolet and X-ray emission of the long period RS CVn star Sigma Geminorum

    NASA Technical Reports Server (NTRS)

    Engvold, O.; Elgaroy, O.; Jensen, E.; Joras, P. B.; Ayres, T. R.

    1988-01-01

    Observations of the RS CVn binary Sigma Gem were obtained in 1984 with the IUE and Exosat satellites. The longitudes of two starspot regions relative to the cental meridian are derived from the photometric data using an improved value of the orbital period. The observations support the theory that large active regions associated with starspots are responsible for the enhanced line emission commonly seen in RS CVn systems.

  16. CNC electrical discharge machining centers

    SciTech Connect

    Jaggars, S.R.

    1991-10-01

    Computer numerical control (CNC) electrical discharge machining (EDM) centers were investigated to evaluate the application and cost effectiveness of establishing this capability at Allied-Signal Inc., Kansas City Division (KCD). In line with this investigation, metal samples were designed, prepared, and machined on an existing 15-year-old EDM machine and on two current technology CNC EDM machining centers at outside vendors. The results were recorded and evaluated. The study revealed that CNC EDM centers are a capability that should be established at KCD. From the information gained, a machine specification was written and a shop was purchased and installed in the Engineering Shop. The older machine was exchanged for a new model. Additional machines were installed in the Tool Design and Fabrication and Precision Microfinishing departments. The Engineering Shop machine will be principally used for the following purposes: producing deep cavities in small corner radii, machining simulated casting models, machining difficult-to-machine materials, and polishing difficult-to-hand polish mold cavities. 2 refs., 18 figs., 3 tabs.

  17. Rotational modulation and flares on RS CVn and BY Draconis stars. XIII - IUE spectroscopy and photometry of II Pegasi during September 1986

    NASA Technical Reports Server (NTRS)

    Doyle, J. G.; Butler, C. J.; Byrne, P. B.; Rodono, M.; Swank, J.

    1989-01-01

    UV spectroscopy obtained for the RS CVn star II Pegasi in September, 1986, indicates the presence of a rotational modulation effect for the Mg II h and k and O I 1305 A lines; the largest flux is observed when the primary spot concentration is nearly on the opposite hemisphere, and the rotational modulation is noted to be of opposite sense to that observed in 1981. Optical photometry shows the largest concentration of spots on one hemisphere ever observed on II Peg, implying a spot group covering over 50 percent of the projected area of one hemisphere.

  18. Rotational modulation and flares on RS CVn and BY Draconis stars. XIII - IUE spectroscopy and photometry of II Pegasi during September 1986

    NASA Astrophysics Data System (ADS)

    Doyle, J. G.; Butler, C. J.; Byrne, P. B.; Rodono, M.; Swank, J.; Fowles, W.

    1989-10-01

    UV spectroscopy obtained for the RS CVn star II Pegasi in September, 1986, indicates the presence of a rotational modulation effect for the Mg II h and k and O I 1305 A lines; the largest flux is observed when the primary spot concentration is nearly on the opposite hemisphere, and the rotational modulation is noted to be of opposite sense to that observed in 1981. Optical photometry shows the largest concentration of spots on one hemisphere ever observed on II Peg, implying a spot group covering over 50 percent of the projected area of one hemisphere.

  19. ROSSITER-MCLAUGHLIN OBSERVATIONS OF 55 Cnc e

    SciTech Connect

    López-Morales, Mercedes; Rodler, Florian; Dumusque, Xavier; Buchhave, Lars A.; Latham, David W.; Triaud, Amaury H. M. J.; Harutyunyan, Avet; Hoyer, Sergio; Alonso, Roi; Gillon, Michaël; Kaib, Nathan A.; Lovis, Christophe; Pepe, Francesco; Queloz, Didier; Ségransan, Damien; Udry, Stéphane; Raymond, Sean N.; Waldmann, Ingo P.

    2014-09-10

    We present Rossiter-McLaughlin observations of the transiting super-Earth 55 Cnc e collected during six transit events between 2012 January and 2013 November with HARPS and HARPS-N. We detect no radial velocity signal above 35 cm s{sup –1} (3σ) and confine the stellar v sin i {sub *} to 0.2 ± 0.5 km s{sup –1}. The star appears to be a very slow rotator, producing a very low amplitude Rossiter-McLaughlin effect. Given such a low amplitude, the Rossiter-McLaughlin effect of 55 Cnc e is undetected in our data, and any spin-orbit angle of the system remains possible. We also performed Doppler tomography and reach a similar conclusion. Our results offer a glimpse of the capacity of future instrumentation to study low amplitude Rossiter-McLaughlin effects produced by super-Earths.

  20. Rossiter-McLaughlin Observations of 55 Cnc e

    NASA Astrophysics Data System (ADS)

    López-Morales, Mercedes; Triaud, Amaury H. M. J.; Rodler, Florian; Dumusque, Xavier; Buchhave, Lars A.; Harutyunyan, Avet; Hoyer, Sergio; Alonso, Roi; Gillon, Michaël; Kaib, Nathan A.; Latham, David. W.; Lovis, Christophe; Pepe, Francesco; Queloz, Didier; Raymond, Sean N.; Ségransan, Damien; Waldmann, Ingo P.; Udry, Stéphane

    2014-09-01

    We present Rossiter-McLaughlin observations of the transiting super-Earth 55 Cnc e collected during six transit events between 2012 January and 2013 November with HARPS and HARPS-N. We detect no radial velocity signal above 35 cm s-1 (3σ) and confine the stellar v sin i sstarf to 0.2 ± 0.5 km s-1. The star appears to be a very slow rotator, producing a very low amplitude Rossiter-McLaughlin effect. Given such a low amplitude, the Rossiter-McLaughlin effect of 55 Cnc e is undetected in our data, and any spin-orbit angle of the system remains possible. We also performed Doppler tomography and reach a similar conclusion. Our results offer a glimpse of the capacity of future instrumentation to study low amplitude Rossiter-McLaughlin effects produced by super-Earths.

  1. The photosphere and chromosphere of the RS Canum Venaticorum star, II Pegasi. II. A multi-wavelength campaign in August/September 1992

    NASA Astrophysics Data System (ADS)

    Byrne, P. B.; Abdul Aziz, H.; Amado, P. J.; Arevalo, M. J.; Avgoloupis, S.; Doyle, J. G.; Eibe, M. T.; Elliott, K. H.; Jeffries, R. D.; Lanzafame, A. C.; Lazaro, C.; Murphy, H. M.; Neff, J. E.; Panov, K. P.; Sarro, L. M.; Seiradakis, J. H.; Spencer, R. E.

    1998-02-01

    We describe multi-wavelength, simultaneous observations of the RS CVn star, II Pegasi, most of which were obtained during the first three weeks of September 1992. These observations were made using optical and infra-red broad-band photometry, ultraviolet and optical spectroscopy and microwave monitoring. We have detected photospheric spots and chromospheric flares, as well as deriving a description of mean conditions in the quiet chromosphere. One of the flares, observed in optical photometry and ultraviolet spectroscopy is one of the most energetic ever observed on this star. We demonstrate that in its ``quiescent'' state II Peg is continually variable in most of its chromospheric emissions, as well as in its coronal output.

  2. Discovery of phase-locked variable polarization in an RS Canum Venaticorum-like star, HR 5110

    NASA Technical Reports Server (NTRS)

    Barbour, M. S.; Kemp, J. C.

    1981-01-01

    Using measurements on 79 nights in 1980 January-August, it is established that the polarization in the ultraviolet (U band) varies synchronously on the known binary period of 2.6132 days, with a peak-to-peak amplitude of 0.03%. The pattern is mainly second harmonic in character, as typical of binary star examples such as Algol and Upsilon Her. Reflection by the cooler star, by a plasma concentration, or both, is suggested. The scale of the polarization seems to be consistent with Rayleigh scattering by neutral hydrogen on the cooler star, and a roughly lambda to the -4th wavelength dependence should be searched for. The QU curve suggests a sizeable inclination for the system, of about 45 deg, but this is preliminary. Separately, a possible weak periodicity might be present on a subsidiary period, conceivably related to a rotating star spot.

  3. TX Cnc AS A MEMBER OF THE PRAESEPE OPEN CLUSTER

    SciTech Connect

    Zhang, X. B.; Deng, L.; Lu, P.

    2009-08-15

    We present B-, V-, and I-band CCD photometry of the W UMa-type binary system TX Cnc, which is a member star of the Praesepe open cluster. Based on the observations, new ephemeris and a revised photometric solution of the binary system were derived. Combined with the results of the radial velocity solution contributed by Pribulla et al., the absolute parameters of the system were determined. The mass, radius, and luminosity of the primary component are derived to be 1.35 {+-} 0.02 M {sub sun}, 1.27 {+-} 0.04 R {sub sun}, and 2.13 {+-} 0.11 L {sub sun}. Those for the secondary star are computed as 0.61 {+-} 0.01 M {sub sun}, 0.89 {+-} 0.03 R {sub sun}, and 1.26 {+-} 0.07 L {sub sun}, respectively. Based on these results, a distance modulus of (m - M) {sub V} = 6.34 {+-} 0.05 is determined for the star. It confirms the membership of TX Cnc to the Praesepe open cluster. The evolutionary status and the physical nature of the binary system are discussed compared with the theoretical model.

  4. Motion Verified Red Stars (MoVeRS): A Catalog of Proper Motion Selected Low-mass Stars from WISE, SDSS, and 2MASS

    NASA Astrophysics Data System (ADS)

    Theissen, Christopher A.; West, Andrew A.; Dhital, Saurav

    2016-02-01

    We present a photometric catalog of 8,735,004 proper motion selected low-mass stars (KML-spectral types) within the Sloan Digital Sky Survey (SDSS) footprint, from the combined SDSS Data Release 10 (DR10), Two Micron All-Sky Survey (2MASS) point-source catalog (PSC), and Wide-field Infrared Survey Explorer (WISE) AllWISE catalog. Stars were selected using r - i, i - z, r - z, z - J, and z - W1 colors, and SDSS, WISE, and 2MASS astrometry was combined to compute proper motions. The resulting 3,518,150 stars were augmented with proper motions for 5,216,854 earlier type stars from the combined SDSS and United States Naval Observatory B1.0 catalog (USNO-B). We used SDSS+USNO-B proper motions to determine the best criteria for selecting a clean sample of stars. Only stars whose proper motions were greater than their 2σ uncertainty were included. Our Motion Verified Red Stars catalog is available through SDSS CasJobs and VizieR.

  5. Synthetical Reliability Analysis Model of CNC Software System

    NASA Astrophysics Data System (ADS)

    Xu, Yue; Xia, Yinjie; Wan, Yi

    CNC technology is the core of advanced manufacturing technology, and CNC software system is the very important part of numerical control system. The entire CNC system will not work normally, once the potential failure makes the software invalid. As to the current study of CNC sysytem, in use of the FAULT glitch tree, established a glitch tree for the CNC system; find the minimum cut sets with Fussed method and then according to the probability of several common glitches, make quantitative analysis in the reliability of the CNC system so that scientific ways can be provided for the reliability design, maintenance and management of the CNC system.

  6. BD Andromedae: A new short-period RS CVn eclipsing binary star with a distant tertiary body in a highly eccentric orbit

    SciTech Connect

    Kim, Chun-Hwey; Song, Mi-Hwa; Yoon, Jo-Na; Jeong, Min-Ji; Han, Wonyong

    2014-06-20

    A photometric study of BD And was made through the analysis of two sets of new BVR light curves. The light curves with migrating photometric waves outside eclipse show that BD And is a short-period RS CVn-type binary star. The analysis of all available timings reveals that the orbital period has varied in a strictly cyclical way with a period of 9.2 yr. The periodic variation most likely arises from the light-time effect due to a tertiary moving in a highly elliptical orbit (e {sub 3} = 0.76). The Applegate mechanism could not operate properly in the eclipsing pair. The light curves were modeled with two large spots on the hotter star and a large third light amounting to about 14% of the total systemic light. BD And is a triple system: a detached binary system consisting of two nearly equal solar-type stars with an active primary star and a G6-G7 tertiary dwarf. The absolute dimensions of the eclipsing pair and tertiary components were determined. The three components with a mean age of about 5.8 Gyr are located at midpositions in main-sequence bands. The radius of the secondary is about 17% larger than that deduced from stellar models. The orbital and radiometric characteristics of the tertiary are intensively investigated. One important feature is that the mutual inclination between two orbits is larger than 60°, implying that Kozai cycles had occurred very efficiently in the past. The possible past and future evolutions of the BD And system, driven by KCTF and MBTF, are also discussed.

  7. Rotational modulation and flares on RS CVn and BY Dra stars. III - IUE observations of V711 Tau (= HR 1099), II Peg, and AR Lac

    NASA Technical Reports Server (NTRS)

    Rodono, M.; Byrne, P. B.; Neff, J. E.; Linsky, J. L.; Simon, T.

    1987-01-01

    Observations of three RS CVn stars, which were obtained over the stellar rotation cycles with the IUE satellite, are presented. Emission lines from high-temperature transition regions and chromospheres analogous to those observed in the solar spectrum were observed. The only visible component of II Peg and both components of V711 Tau and AR Lac appear to be chromospherically active. For the latter systems, the Mg II line surface flux from the G-type star is higher than that from the K subgiant, which dominates the observed UV line flux. Moreover, evidence of long-term ultraviolet variability is presented for AR Lac. The emission line fluxes for II Peg and, marginally, for the other two systems were observed to vary in antiphase with the optical variations at the time of the IUE observations. By comparing the results of Rodono et al. (1986) for two-spot models with the variation of UV line flux, evidence of a close spatial correlation between spot and plagelike features is found.

  8. Entering the operative correction machining processes CNC

    NASA Astrophysics Data System (ADS)

    Nekrasov, R. Yu; Starikov, A. I.; Lasukov, A. A.

    2015-09-01

    The article describes the solution to the problem of compensation of errors occurring during machining on CNC machines. We propose a method of mathematical modeling of processes diagnostics and control of technological equipment. The results of the diagnosis of the CNC machine, as well as the mathematical model describing the dependence of the positioning error of the executive bodies of operating component of cutting force PZ, in the range of movement OX.

  9. Improving Energy Efficiency in CNC Machining

    NASA Astrophysics Data System (ADS)

    Pavanaskar, Sushrut S.

    We present our work on analyzing and improving the energy efficiency of multi-axis CNC milling process. Due to the differences in energy consumption behavior, we treat 3- and 5-axis CNC machines separately in our work. For 3-axis CNC machines, we first propose an energy model that estimates the energy requirement for machining a component on a specified 3-axis CNC milling machine. Our model makes machine-specific predictions of energy requirements while also considering the geometric aspects of the machining toolpath. Our model - and the associated software tool - facilitate direct comparison of various alternative toolpath strategies based on their energy-consumption performance. Further, we identify key factors in toolpath planning that affect energy consumption in CNC machining. We then use this knowledge to propose and demonstrate a novel toolpath planning strategy that may be used to generate new toolpaths that are inherently energy-efficient, inspired by research on digital micrography -- a form of computational art. For 5-axis CNC machines, the process planning problem consists of several sub-problems that researchers have traditionally solved separately to obtain an approximate solution. After illustrating the need to solve all sub-problems simultaneously for a truly optimal solution, we propose a unified formulation based on configuration space theory. We apply our formulation to solve a problem variant that retains key characteristics of the full problem but has lower dimensionality, allowing visualization in 2D. Given the complexity of the full 5-axis toolpath planning problem, our unified formulation represents an important step towards obtaining a truly optimal solution. With this work on the two types of CNC machines, we demonstrate that without changing the current infrastructure or business practices, machine-specific, geometry-based, customized toolpath planning can save energy in CNC machining.

  10. Star Images, Star Performances (College Course File).

    ERIC Educational Resources Information Center

    Butler, Jeremy G.

    1990-01-01

    Describes a course that focuses attention on the position of the actor, especially the star actor, in cinematic and television signification. Divides the course into three sections: "The Star System,""Stars as Images," and "Star Performance." (RS)

  11. MULTIBAND PHOTOMETRIC AND SPECTROSCOPIC ANALYSIS OF HV Cnc

    SciTech Connect

    Gökay, G.; Gürol, B.; Derman, E.

    2013-11-01

    In this paper, radial velocity and VI- and JHK{sub S} - (Two Micron All Sky Survey) band photometric data of the detached system HV Cnc have been analyzed. The primary component of HV Cnc, which is a member of the M67 cluster, is suspected to be either a blue straggler or turn-off star. The system is a single-lined spectroscopic binary and its light curve shows a total eclipse. Spectroscopic observations of the system revealed the third component, which shows contribution to the total light of the system. Light curve and radial velocity data have been analyzed using the Wilson-Devinney (W-D) code and JHK{sub S} filter definitions computed for the W-D code in this work. Our analysis shows that the mass and radius of the primary and secondary components are 1.31 M {sub ☉}, 0.52 M {sub ☉}, 1.87 R {sub ☉}, and 0.48 R {sub ☉}, respectively. All results are compared with previously published literature values and discussed.

  12. Multiband Photometric and Spectroscopic Analysis of HV Cnc

    NASA Astrophysics Data System (ADS)

    Gkay, G.; Grol, B.; Derman, E.

    2013-11-01

    In this paper, radial velocity and VI- and JHKS - (Two Micron All Sky Survey) band photometric data of the detached system HV Cnc have been analyzed. The primary component of HV Cnc, which is a member of the M67 cluster, is suspected to be either a blue straggler or turn-off star. The system is a single-lined spectroscopic binary and its light curve shows a total eclipse. Spectroscopic observations of the system revealed the third component, which shows contribution to the total light of the system. Light curve and radial velocity data have been analyzed using the Wilson-Devinney (W-D) code and JHKS filter definitions computed for the W-D code in this work. Our analysis shows that the mass and radius of the primary and secondary components are 1.31 M ?, 0.52 M ?, 1.87 R ?, and 0.48 R ?, respectively. All results are compared with previously published literature values and discussed.

  13. The photosphere and chromosphere of the RS Canum Venaticorum star, II Pegasi I. Spots and chromospheric emission in 1991.

    NASA Astrophysics Data System (ADS)

    Byrne, P. B.; Panagi, P. M.; Lanzafame, A. C.; Avgoloupis, S.; Huenemoerder, D. P.; Kilkenny, D.; Marang, F.; Panov, K. P.; Roberts, G.; Seiradakis, J. H.; van Wyk, F.

    1995-07-01

    We report on high-resolution spectroscopy of the RSCVn binary IIPeg, along with contemporaneous UBV(RI)_KC_ photometry, including partly simultaneous U-band flare monitoring, during the third quarter of 1991. The spectroscopy was taken at two epochs separated by more than 6(1)/(2) weeks or seven rotations of IIPeg. At the first epoch we have observed the three chromospheric lines, Hα, Hβ and HeID_3_, over a single rotation and at the second epoch we observed almost the entire visible region, for a substantial fraction of one rotation, including Hα-Hɛ and CaIIH. Our photometric results show that there was an unusually complicated spot distribution at this epoch, with at least three centres of activity discernable. We demonstrate, for the first time on a spotted late-type star, that these centres of spot activity have significantly different mean temperatures from one another. Furthermore, our derived spot temperatures are markedly lower than those previously derived from such multicolour photometry and more similar to those derived spectroscopically. Using multiple repeat exposures on each spectral line within each night, we are confident that we have derived a mean, non-flaring spectrum at each observational phase. Furthermore, the line flux variations at the two epochs repeat very well, suggesting that the mean global chromospheric structures are stable on a 1(1)/(2) months time scale. We discuss the implications of the mean spectra for the non-flaring atmosphere of IIPeg and conclude that, in the region of formation of the Hα line, velocity fields are required to account for the line profile. These results suggest upward motions of the deep chromosphere with a less dramatic downflow in the high chromosphere. We examine the variation of the chromospheric line fluxes as a function of spot visibility and conclude that there is only a very loose spatial correlation of chromsopheric heating with spots. The motions suggested from the Hα profile variations appear to be spot-associated.

  14. An intelligent CNC machine control system architecture

    SciTech Connect

    Miller, D.J.; Loucks, C.S.

    1996-10-01

    Intelligent, agile manufacturing relies on automated programming of digitally controlled processes. Currently, processes such as Computer Numerically Controlled (CNC) machining are difficult to automate because of highly restrictive controllers and poor software environments. It is also difficult to utilize sensors and process models for adaptive control, or to integrate machining processes with other tasks within a factory floor setting. As part of a Laboratory Directed Research and Development (LDRD) program, a CNC machine control system architecture based on object-oriented design and graphical programming has been developed to address some of these problems and to demonstrate automated agile machining applications using platform-independent software.

  15. Rotational modulation and flares on RS Canum Venaqticorum and BY Draconis stars. XII - Near-to-simultaneous high resolution UV and optical observations of II Pegasi during July 1984

    NASA Astrophysics Data System (ADS)

    Byrne, P. B.; Panagi, P.; Doyle, J. G.; Englebrecht, C. A.; McMahan, R.; Marang, F.; Wegner, G.

    1989-04-01

    Nearly simultaneous high resolution ground-based optical and IUE satellite UV spectroscopy and an optical light curve of the RS CVn star II Peg are presented. It is shown that the chromospheric and transition region radiative losses of the star in July 1984 are lower than previously recorded means. The flux in the Lyman-alpha line is estimated and evidence is given for variability in all of the emission lines. This variability appears to be correlated with the optical spots. Line profiles at two rotational phases for the principal UV emission lines show an excess broadening over and above the combined instrumental plus Doppler broadening.

  16. Development of Lathe Attachment for a CNC Machine

    NASA Astrophysics Data System (ADS)

    Roy, V.; Kumar, S.

    2013-04-01

    A lathe attachment has been developed for an existing CNC machine (installed with rapid prototyping attachment) using conceptual design. The CNC machine operates on mechatronic controls and a computer interface called CAMSOFT, and is used as a CNC Lathe after installing the respective attachment to it. The conceptual design phase, starts from an idea and different components of the lathe are designed as attachment using CAD modelling and is followed by fabrication phase. The lathe attachment is successfully developed and is installed to the CNC machine. The working of the CNC Lathe attachment is checked by making some machining operation like turning and thread cutting. The machining operations are successfully done. The CNC machine becomes multifunctional with the presently developed lathe attachment and the existing RP (rapid prototyping) attachment, and can be used accordingly by installing the respective attachment to it. The CNC machine is useful for carrying research work in both the fields, when installed with the appropriate attachment.

  17. RS Canum Venaticorum

    NASA Astrophysics Data System (ADS)

    Rodonò, M.; Murdin, P.

    2000-11-01

    RSCVn=RS Canum Venaticorum (BD +36° 2344, HD 114519; α1950.0=13h08m18s, δ1950.0=+36°12'.0; Δd=2.79 s yr-1, Δδ=-0.319' yr-1) is a detached CLOSE BINARY STAR (F5 V+K2 IV) in the CANES VENATICI constellation (cf Rodonò et al 1995 for a discussion of the spectral classification). In addition to the canonical eclipse-related light variability, early photometric observations had already shown uneven o...

  18. CNC Machining Of The Complex Copper Electrodes

    NASA Astrophysics Data System (ADS)

    Popan, Ioan Alexandru; Balc, Nicolae; Popan, Alina

    2015-07-01

    This paper presents the machining process of the complex copper electrodes. Machining of the complex shapes in copper is difficult because this material is soft and sticky. This research presents the main steps for processing those copper electrodes at a high dimensional accuracy and a good surface quality. Special tooling solutions are required for this machining process and optimal process parameters have been found for the accurate CNC equipment, using smart CAD/CAM software.

  19. Very low luminosity stars with very large amplitude flares

    NASA Technical Reports Server (NTRS)

    Schaefer, Bradley E.

    1990-01-01

    CCD frames of CZ Cnc, KY Cep, the gamma-ray burster optical transient, and NSV 12006 are analyzed. Also studied are 549 archival photographic plates of the CZ Cnc field. These observations are compared with the data of Lovas (1976). Flare events on CZ Cnc are examined. Based on the data it is noted that CZ Cnc is a main-sequence star, has a magnitude of 16.1, a distance of 100 pc, occasional large-amplitude flares, and frequent flares with amplitudes greater than 4 mag.

  20. Advanced CNC Programming (EZ-CAM). 439-366.

    ERIC Educational Resources Information Center

    Casey, Joe

    This document contains two units for an advanced course in computer numerical control (CNC) for computer-aided manufacturing. It is intended to familiarize students with the principles and techniques necessary to create proper CNC programs using computer software. Each unit consists of an introduction, instructional objectives, learning materials,

  1. Understanding and Writing G & M Code for CNC Machines

    ERIC Educational Resources Information Center

    Loveland, Thomas

    2012-01-01

    In modern CAD and CAM manufacturing companies, engineers design parts for machines and consumable goods. Many of these parts are cut on CNC machines. Whether using a CNC lathe, milling machine, or router, the ideas and designs of engineers must be translated into a machine-readable form called G & M Code that can be used to cut parts to precise…

  2. Understanding and Writing G & M Code for CNC Machines

    ERIC Educational Resources Information Center

    Loveland, Thomas

    2012-01-01

    In modern CAD and CAM manufacturing companies, engineers design parts for machines and consumable goods. Many of these parts are cut on CNC machines. Whether using a CNC lathe, milling machine, or router, the ideas and designs of engineers must be translated into a machine-readable form called G & M Code that can be used to cut parts to precise

  3. Advanced CNC Programming (EZ-CAM). 439-366.

    ERIC Educational Resources Information Center

    Casey, Joe

    This document contains two units for an advanced course in computer numerical control (CNC) for computer-aided manufacturing. It is intended to familiarize students with the principles and techniques necessary to create proper CNC programs using computer software. Each unit consists of an introduction, instructional objectives, learning materials,…

  4. Rotational modulation and flares on RS CVn and BY Dra stars. VI - Physical parameters of the chromospheres/transition regions of V 711 Tau (HR 1099), II Peg and AR Lac during October 1981

    NASA Technical Reports Server (NTRS)

    Byrne, P. B.; Doyle, J. G.; Brown, A.; Linsky, J. L.; Rodono, M.

    1987-01-01

    Ground-based optical and IUE satellite-ultraviolet observations of three RS CVn stars are combined with density sensitive line ratios and differential emission measure curves to describe the physical conditions in their outer atmospheres. Solar-like densities are found to be representative of average conditions on two of the stars, V 711 Tau and AR Lac. The total radiative losses from these two stars are estimated and found to be larger than the sun by at least two orders of magnitude. Consideration of the volume emitting in two of the principal transition region lines suggests a possible relation between the disk 'filling factor' for these two lines and the dynamo-related Rossby number. Only one hemisphere of the star II Peg, the one showing least evidence of starspots, is similar. On the opposite hemisphere the presence of a discrete emitting region is deduced which is almost coincident in phase with the passage of the dominant optical spot group across the visible disk. The dimensions of this region, and an illustrative interpretation in terms of a large emitting magnetic loop, are discussed. It is compared to large active region loops on the sun.

  5. Effect of cellulose nanocrystals (CNC) on rheological and mechanical properties and crystallization behavior of PLA/CNC nanocomposites.

    PubMed

    Kamal, Musa R; Khoshkava, Vahid

    2015-06-01

    In earlier work, we reported that spray freeze drying of cellulose nanocrystals (CNC) yields porous agglomerate structures. On the other hand, the conventional spray dried CNC (CNCSD) and the freeze dried CNC (CNCFD) produce compact solid structures with very low porosity. As it is rather difficult to obtain direct microscopic evidence of the quality of dispersion of CNC in polymer nanocomposites, it was shown that supporting evidence of the quality and influence of dispersion in a polypropylene (PP)/CNC nanocomposite could be obtained by studying the rheological behavior, mechanical properties and crystallization characteristics of PP/CNC nanocomposites. In an effort to produce a sustainable, fully biosourced, biodegradable nanocomposite, this manuscript presents the results of a study of the rheological, mechanical and crystallization behavior of PLA/CNCSFD nanocomposites obtained by melt processing. The results are analyzed to determine CNC network formation, rheological percolation threshold concentrations, mechanical properties in the rubbery and glassy states, and the effect of CNCSFD on crystalline nucleation and crystallization rates of PLA. These results suggest that the porosity and network structure of CNCSFD agglomerates contribute significantly to good dispersion of CNC in the PLA matrix. PMID:25843840

  6. Application of the machine CNC system in laser marking

    NASA Astrophysics Data System (ADS)

    Zhao, Wei; Sa, Yu; Liu, Xuebin; Feng, Na

    2008-03-01

    Laser marking is non-contact, non-pollution and permanence so it will be used widely. Laser marking is related essentially with the CNC machining. It is proposed that the control method and algorithm in the CNC system can be applied to the laser marking. The comparability of them is summarized on the base of analyzing the composition characters of the open-architectured CNC system and the laser marking. The mode of Laser marking includes scan mode and path one which are researched in detail in this paper. For path mode, the steps and code translation of CNC machining are applied. This method is not only useful to settle the edge effect, but also improve the marking efficiency.

  7. GROUND-BASED TRANSIT OBSERVATIONS OF THE SUPER-EARTH 55 Cnc e

    SciTech Connect

    De Mooij, E. J. W.; López-Morales, M.; Karjalainen, R.; Hrudkova, M.; Jayawardhana, Ray

    2014-12-20

    We report the first ground-based detections of the shallow transit of the super-Earth exoplanet 55 Cnc e using a 2 m class telescope. Using differential spectrophotometry, we observed one transit in 2013 and another in 2014, with average spectral resolutions of ∼700 and ∼250, spanning the Johnson BVR photometric bands. We find a white light planet-to-star radius ratio of 0.0190{sub −0.0027}{sup +0.0023} from the 2013 observations and 0.0200{sub −0.0018}{sup +0.0017} from the 2014 observations. The two data sets combined result in a radius ratio of 0.0198{sub −0.0014}{sup +0.0013}. These values are all in agreement with previous space-based results. Scintillation noise in the data prevents us from placing strong constraints on the presence of an extended hydrogen-rich atmosphere. Nevertheless, our detections of 55 Cnc e in transit demonstrate that moderate-sized telescopes on the ground will be capable of routine follow-up observations of super-Earth candidates discovered by the Transiting Exoplanet Survey Satellite around bright stars. We expect it also will be possible to place constraints on the atmospheric characteristics of those planets by devising observational strategies to minimize scintillation noise.

  8. Chemical compositions of neutron-process elements in low-metallicity stars - tracers of r and r+s nucleosynthesis processes .

    NASA Astrophysics Data System (ADS)

    Ivans, I. I.; Bisterzo, S.; Gallino, R.

    Employing spectra obtained with the near-UV sensitive detector on the Keck I HIRES, comprehensive chemical composition analyses have been performed on the neutron-capture-element-rich star, HD221170 ([Fe/H] = -2.2; Ivans et al 2006), and the binary blue metal-poor star, BPS CS29497-030 (-2.6; Ivans et al. 2005). The heavy element abundances of HD221170 are fit exquisitely well by a scaled-solar r-process abundance pattern with no contribution from the s-process. In contrast, the abundance pattern of CS29497-030 seems best fit by an AGB model with s-processing that also includes very significant amounts of pre-enrichment of r-process material in the protostellar cloud out of which the binary system formed.

  9. Far Ultraviolet Spectroscopy of Three Long Period Nova-Like Variables, V363 Aur, AC Cnc and RZ Gru

    NASA Astrophysics Data System (ADS)

    Bisol, Alexandra; Sion, E. M.

    2011-01-01

    We have selected three nova-like variables: V363 Aur, RZ Gru and AC Cnc, all of which are UX UMa types, having similar orbital periods well beyond the 3 to 4 hour range where most nova-likes are found. All should have very similar secondary stars given the fact that they their physical parameters are so similar. V363 Aur is a bona fide SW Sex star, and AC Cnc is a probable one, while RZ Gru is not a member of the SW Sex subclass. Our objective is to carry out the first synthetic spectral analysis of far ultraviolet spectra of the three systems using state-of-the-art models both of accretion disks and photospheres. Therefore we shall compare the distances we obtain from the best fitting synthetic spectral models to other distance estimates in the literature. We present model-derived accretion rates and distances for all three systems. The FUV flux range of RZ Gru and V363 Aur is dominated by radiation from an optically thick, steady state, accretion but for AC Cnc, we find that a hot white dwarf accounts for 70% of the FUV flux. We compare the FUV characteristics and physical properties of these three long period nova-like systems to the properties of other nova-likes at shorter periods. This work was supported in part by NSF grant AST0807892 to Villanova University.

  10. Stars

    NASA Astrophysics Data System (ADS)

    Capelato, Hugo Vicente

    1999-01-01

    We will begin our study with a more or less superficial inspection of the "forest" of stars that we see in the skies. The first thing we notice is that, as sources of light, they are much weaker than the Sun. Second, their apparent colors vary; from a bluish-white in most of them to a reddish-yellow, which is rarer. There is also a third aspect, though it is not very obvious to the naked eye: most of the stars group themselves in small families of two, three or more members. A good example is the Alpha Centauri, the closest star to us, which, in fact, is a triple system of stars. Another is the group of 7 stars that make up the Pleiades, which will be discussed later on. In fact, almost half of the stars are double systems with only two members, called binary stars. Most of these double stars, though together, are separated by several astronomical units (one astronomical unit, AU, is the distance from Earth to the sun: see Chapter 1), and revolve around each other over periods of several years. And yet the revolutions of some binary stars, separated by much smaller distances, occur in only a few hours! These stars are so close to each other that they can share enveloping material. Often this exchange occurs in a somewhat violent manner. Local explosions may occur, expelling matter away from the system. In other binary systems, where one of the components is a very compact, dense star, companion material flows more calmly, making up a light disk around the compact star.

  11. CNC grinding of valve housing piston holes

    SciTech Connect

    Ashbaugh, F.A.

    1991-11-01

    Grinding has traditionally been used for machining operations requiring close dimensional tolerances and better surface finishes than can be obtained from other metal removal techniques. Using a grinding process for the last metal removal operation, the close tolerances and surface finishes can be easily held while eliminating the adverse conditions from the current metal removal processes. Pre-machined test parts were sent to a machine tool supplier to have the critical inside features of a typical piston bore finish machined using an internal CNC grinder equipped with high-frequency spindles. The piston bore and sealing angle were ground using a standard 120-grit silicon carbide wheel. The wafer step was machined using a solid carbide tool designed and built at Allied-Signal Inc., Kansas City Division (KCD). Six consecutive parts were machined for evaluation. The repeatability on all six parts was within print requirements. The inside corner radii was less than 0.002 in. and the surface finish was 8.2 arithmetical average or better as defined by ANSI B46.1, Surface Texture. Machining parts by this grinding process would eliminate bellmouth, chatter, waviness, and traveler polishing operations. It would produce a superior surface finish, small inside radii, and small easily removable burrs. It would also hold tolerances closer and significantly reduce scrap, rework, rejects, and deviations. 1 fig.

  12. Final Report: CNC Micromachines LDRD No.10793

    SciTech Connect

    JOKIEL JR., BERNHARD; BENAVIDES, GILBERT L.; BIEG, LOTHAR F.; ALLEN, JAMES J.

    2003-04-01

    The three-year LDRD ''CNC Micromachines'' was successfully completed at the end of FY02. The project had four major breakthroughs in spatial motion control in MEMS: (1) A unified method for designing scalable planar and spatial on-chip motion control systems was developed. The method relies on the use of parallel kinematic mechanisms (PKMs) that when properly designed provide different types of motion on-chip without the need for post-fabrication assembly, (2) A new type of actuator was developed--the linear stepping track drive (LSTD) that provides open loop linear position control that is scalable in displacement, output force and step size. Several versions of this actuator were designed, fabricated and successfully tested. (3) Different versions of XYZ translation only and PTT motion stages were designed, successfully fabricated and successfully tested demonstrating absolutely that on-chip spatial motion control systems are not only possible, but are a reality. (4) Control algorithms, software and infrastructure based on MATLAB were created and successfully implemented to drive the XYZ and PTT motion platforms in a controlled manner. The control software is capable of reading an M/G code machine tool language file, decode the instructions and correctly calculate and apply position and velocity trajectories to the motion devices linear drive inputs to position the device platform along the trajectory as specified by the input file. A full and detailed account of design methodology, theory and experimental results (failures and successes) is provided.

  13. CO And HI Emission from The Circumstellar Envelopes of Some Evolved Stars*

    NASA Astrophysics Data System (ADS)

    Diep, P. N.; Hoai, D. T.; Nhung, P.; Tuan-Anh, P.; Le Bertre, T.; Winters, J. M.; Matthews, L. D.; Phuong, N. T.; Thao, N. T.; Darriulat, P.

    2016-02-01

    Studies of the CO and HI radio emission of some evolved stars are presented using data collected by the IRAM Plateau de Bure interferometer and Pico Veleta telescope, the Nançay Radio Telescope and the JVLA and ALMA arrays. Approximate axial symmetry of the physical and kinematic properties of the circumstellar envelope (CSE) are observed in CO emission , in particular, from RS Cnc, EP Aqr and the Red Rectangle. A common feature is the presence of a bipolar outflow causing an enhanced wind velocity in the polar directions. I emission extends to larger radial distances than probed by CO emission and displays features related to the interaction between the stellar outflow and interstellar matter. With its unprecedented sensitivity, FAST will open a new window on such studies. Its potential in this domain is briefly illustrated.

  14. Rotational modulation and flares on RS CVn and BY Dra-type stars. V - Exosat and IUE observations of a flare on EQ Pegasi

    NASA Technical Reports Server (NTRS)

    Haisch, B. M.; Butler, C. J.; Doyle, J. G.; Rodono, M.

    1987-01-01

    Time-trailed UV spectra and a soft X-ray lightcurve were obtained during a flare on the binary dMe star EQ Peg AB. On the basis of solar flare Mg II surface fluxes and an about 70-percent enhancement in the disk-integrated flux during the flare on EQ Peg, it is estimated that the chromospheric flare covered about 1.5 percent of the stellar surface. The size scale is estimated to be comparable to that of a solar two-ribbon flare. This unusual flare is noted to exhibit a low-energy soft X-ray rise phase which is longer than that of most flares; it is longer than the decay phase and peaks much later than the medium energy light curve. Evidence of variable Fe II emission and variable continuum emission in select UV bands during the flare is noted.

  15. CNC Turning Center Advanced Operations. Computer Numerical Control Operator/Programmer. 444-332.

    ERIC Educational Resources Information Center

    Skowronski, Steven D.; Tatum, Kenneth

    This student guide provides materials for a course designed to introduce the student to the operations and functions of a two-axis computer numerical control (CNC) turning center. The course consists of seven units. Unit 1 presents course expectations and syllabus, covers safety precautions, and describes the CNC turning center components, CNC

  16. New ephemerides for 120 eclipsing binary stars

    NASA Astrophysics Data System (ADS)

    Mallama, A. D.

    1980-10-01

    New ephemerides based on data from 1968 to 1978 have been derived for 120 eclipsing binary stars with Algol-like light curves. The original visual timings are grouped into yearly normals of rather high accuracy. The program stars are: RT And, UU And, xZ And, RY Aqr, CX Aqr, CZ Aqr, EE Aqr, V346 Aql, WW Aur, UW Boo, ZZ Boo, Y Cam, SV Cam, AL Cam, TU Cnc, R CMa, RX CMa, TU CMa, AG CMi, TV Cap, Rz Cas, TV Cas, AB Cas, U Cep, EG Cep, RW Cet, U CrB, V Crt, Y Cyg, SW Cyg, UW Cyg, WW Cyg, zZ Cyg, AE Cyg, V456 Cyg, V477 Cyg, V687 Cyg, V728 Cyg, W Del, TY Del, YY Del, FZ Del, Z Dra, RR Dra, TW Dra, A' Dra, S Equ, TZ Eri, WX Eri, RW Gem, TX Gem, YY Gem, AF Gem, RX Her, SZ Her, TU Her, TX Her, UX Her, CC Her, CT Her, V338 Her, RX Hya, TW Lac, VX Lac, AU Lac, CM Lac, Y Leo, RW Leo, UU Leo, UV Leo, T LMi, RS Lep, Lib, UZ Lyr, EW Lyr, FL Lyr, RW Mon, TU Mon, BO Mon, U Oph, RV Oph, V449 Oph, FL Ori, FT Ori, UX Peg, BN Peg, DI Peg, Z Per, RT Per, RV Per, ST Per, xZ Per, p Per, Y Psc, xZ Pup, U Sge, XY Sgr, V505 Sgr, RS Sct, AK Ser, AO Ser, RW Tau, HU Tau, X Tri, TX UMa, UX UMa, vV UMa, xZ UMa, zZ UMa, W UMi, RU UMi, UW Vir, AK Vir, BF Vir, BH Vir, Z Vul, AX Vul, BE Vul, BO Vul, and BU Vul.

  17. 28SiO v = 0 J = 1-0 emission from evolved stars

    NASA Astrophysics Data System (ADS)

    de Vicente, P.; Bujarrabal, V.; Díaz-Pulido, A.; Albo, C.; Alcolea, J.; Barcia, A.; Barbas, L.; Bolaño, R.; Colomer, F.; Diez, M. C.; Gallego, J. D.; Gómez-González, J.; López-Fernández, I.; López-Fernández, J. A.; López-Pérez, J. A.; Malo, I.; Moreno, A.; Patino, M.; Serna, J. M.; Tercero, F.; Vaquero, B.

    2016-04-01

    Aims: Observations of 28SiO v = 0J = 1-0 line emission (7-mm wavelength) from asymptotic giant branch (AGB) stars show in some cases peculiar profiles, composed of a central intense component plus a wider plateau. Very similar profiles have been observed in CO lines from some AGB stars and most post-AGB nebulae and, in these cases, they are clearly associated with the presence of conspicuous axial symmetry and bipolar dynamics. We aim to systematically study the profile shape of 28SiO v = 0J = 1-0 lines in evolved stars and to discuss the origin of the composite profile structure. Methods: We present observations of 28SiO v = 0J = 1-0 emission in 28 evolved stars, including O-rich, C-rich, and S-type Mira-type variables, OH/IR stars, semiregular long-period variables, red supergiants and one yellow hypergiant. Most objects were observed in several epochs, over a total period of time of one and a half years. The observations were performed with the 40 m radio telescope of the Instituto Geográfico Nacional (IGN) in Yebes, Spain. Results: We find that the composite core plus plateau profiles are systematically present in O-rich Miras, OH/IR stars, and red supergiants. They are also found in one S-type Mira (χ Cyg) and in two semiregular variables (X Her and RS Cnc) that are known to show axial symmetry. In the other objects, the profiles are simpler and similar to those observed in other molecular lines. The composite structure appears in the objects in which SiO emission is thought to come from the very inner circumstellar layers, prior to dust formation. The central spectral feature is found to be systematically composed of a number of narrow spikes, except for X Her and RS Cnc, in which it shows a smooth shape that is very similar to that observed in CO emission. These spikes show a significant (and mostly chaotic) time variation, while in all cases the smooth components remain constant within the uncertainties. The profile shape could come from the superposition of standard wide profiles and a group of weak maser spikes confined to the central spectral regions because of tangential amplification. Alternatively, we speculate that the very similar profiles detected in objects that are known to be conspicuously axisymmetric, such as X Her and RS Cnc, and in O-rich Mira-type stars, such as IK Tau and TX Cam, may be indicative of the systematic presence of a significant axial symmetry in the very inner circumstellar shells around AGB stars; such symmetry would be independent of the presence of weak maser effects in the central spikes.

  18. CNC Turning Technician. A Competency-Based Instructional System.

    ERIC Educational Resources Information Center

    Sloan, Kelly; Hilley, Robert

    This competency-based curriculum guide for instructing students in using computer numerically controlled (CNC) turning machines is one of a series of instructional guides for the machinist field developed in Oklahoma. Although developed jointly with Baxter Technologies Corporation and oriented toward the Baxter Vo-Tec 2000 Future Builder CNC…

  19. Implementation of Additive Rapid Prototyping on Retrofit CNC Mill

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Freeform fabrication techniques are gaining popularity as a means of making parts. Layered additive methods are associated with rapid prototyping. Many rapid prototyping methods are commercially proprietary and may cost thousands of dollars. Using a retrofit CNC mill for layered fabrication and C...

  20. Fidget with Widgets: CNC Activity Introduces the Flatbed Router

    ERIC Educational Resources Information Center

    Tryon, Daniel V.

    2006-01-01

    The computer numerical control (CNC) flatbed router is a powerful tool and a must-have piece of equipment for any technology education program in which students will produce a product--whether it involves Manufacturing, Materials Processing, or any of the vast array of Project Lead the Way courses. This article describes an activity--producing a…

  1. Fidget with Widgets: CNC Activity Introduces the Flatbed Router

    ERIC Educational Resources Information Center

    Tryon, Daniel V.

    2006-01-01

    The computer numerical control (CNC) flatbed router is a powerful tool and a must-have piece of equipment for any technology education program in which students will produce a product--whether it involves Manufacturing, Materials Processing, or any of the vast array of Project Lead the Way courses. This article describes an activity--producing a

  2. Generation of gear tooth surfaces by application of CNC machines

    NASA Technical Reports Server (NTRS)

    Litvin, F. L.; Chen, N. X.

    1994-01-01

    This study will demonstrate the importance of application of computer numerically controlled (CNC) machines in generation of gear tooth surfaces with new topology. This topology decreases gear vibration and will extend the gear capacity and service life. A preliminary investigation by a tooth contact analysis (TCA) program has shown that gear tooth surfaces in line contact (for instance, involute helical gears with parallel axes, worm gear drives with cylindrical worms, etc.) are very sensitive to angular errors of misalignment that cause edge contact and an unfavorable shape of transmission errors and vibration. The new topology of gear tooth surfaces is based on the localization of bearing contact, and the synthesis of a predesigned parabolic function of transmission errors that is able to absorb a piecewise linear function of transmission errors caused by gear misalignment. The report will describe the following topics: description of kinematics of CNC machines with six degrees of freedom that can be applied for generation of gear tooth surfaces with new topology. A new method for grinding of gear tooth surfaces by a cone surface or surface of revolution based on application of CNC machines is described. This method provides an optimal approximation of the ground surface to the given one. This method is especially beneficial when undeveloped ruled surfaces are to be ground. Execution of motions of the CNC machine is also described. The solution to this problem can be applied as well for the transfer of machine tool settings from a conventional generator to the CNC machine. The developed theory required the derivation of a modified equation of meshing based on application of the concept of space curves, space curves represented on surfaces, geodesic curvature, surface torsion, etc. Condensed information on these topics of differential geometry is provided as well.

  3. On the polymorphic and morphological changes of cellulose nanocrystals (CNC-I) upon mercerization and conversion to CNC-II.

    PubMed

    Jin, Ersuo; Guo, Jiaqi; Yang, Fang; Zhu, Yangyang; Song, Junlong; Jin, Yongcan; Rojas, Orlando J

    2016-06-01

    Polymorphic and morphological transformations of cellulosic materials are strongly associated to their properties and applications, especially in the case of emerging nanocelluloses. Related changes that take place upon treatment of cellulose nanocrystals (CNC) in alkaline conditions are studied here by XRD, TEM, AFM, and other techniques. The results indicate polymorphic transformation of CNC proceeds gradually in a certain range of alkali concentrations, i.e. from about 8% to 12.5% NaOH. In such transition alkali concentration, cellulose I and II allomorphs coexists. Such value and range of the transition concentration is strongly interdependent with the crystallite size of CNCs. In addition, it is distinctively lower than that for macroscopic fibers (12-15% NaOH). Transmission electron microscopy and particle sizing reveals that after mercerization CNCs tend to associate. Furthermore, TEMPO-oxidized mercerized CNC reveals the morphology of individual nanocrystal of the cellulose II type, which is composed of some interconnected granular structures. Overall, this work reveals how the polymorphism and morphology of individual CNC change in alkali conditions and sheds light onto the polymorphic transition from cellulose I to II. PMID:27083376

  4. Motion Simulation Analysis of Rail Weld CNC Fine Milling Machine

    NASA Astrophysics Data System (ADS)

    Mao, Huajie; Shu, Min; Li, Chao; Zhang, Baojun

    CNC fine milling machine is a new advanced equipment of rail weld precision machining with high precision, high efficiency, low environmental pollution and other technical advantages. The motion performance of this machine directly affects its machining accuracy and stability, which makes it an important consideration for its design. Based on the design drawings, this article completed 3D modeling of 60mm/kg rail weld CNC fine milling machine by using Solidworks. After that, the geometry was imported into Adams to finish the motion simulation analysis. The displacement, velocity, angular velocity and some other kinematical parameters curves of the main components were obtained in the post-processing and these are the scientific basis for the design and development for this machine.

  5. CNC subaperture polishing process arrangement for microroughness minimisation

    NASA Astrophysics Data System (ADS)

    Prochaska, F.; Matousek, O.; Tomka, D.; Polak, J.; Poláková, I.

    2015-01-01

    The aim of this study was to determine the optimal subaperture polishing procedure for aspherical surfaces on the Optotech MCP 250 CNC machine. Due to the fact that the CNC subaperture polishing process runs along well defined paths, certain frequencies develop on the polished surface, which can be limiting for the resulting microroughness. A proper sequence of polishing steps in different tool motion control modes can minimize these frequencies and help to substantially reduce microroughness. In this context, various tool motion control modes ("Spiral spindle mode", "Spiral axis mode" and "Raster mode") in combination with different tools were tested. The resulting microroughness values were observed in the defined mid-frequency and high-frequency areas. The best results, i.e. the lowest microroughness values were obtained using a combination of the processes "Ball spiral axis mode", "FEM raster mode", "spiral spindle 2D FEM correction mode" and "AFJ spiral axis mode"

  6. [MaRS Project

    NASA Technical Reports Server (NTRS)

    Aruljothi, Arunvenkatesh

    2016-01-01

    The Space Exploration Division of the Safety and Mission Assurances Directorate is responsible for reducing the risk to Human Space Flight Programs by providing system safety, reliability, and risk analysis. The Risk & Reliability Analysis branch plays a part in this by utilizing Probabilistic Risk Assessment (PRA) and Reliability and Maintainability (R&M) tools to identify possible types of failure and effective solutions. A continuous effort of this branch is MaRS, or Mass and Reliability System, a tool that was the focus of this internship. Future long duration space missions will have to find a balance between the mass and reliability of their spare parts. They will be unable take spares of everything and will have to determine what is most likely to require maintenance and spares. Currently there is no database that combines mass and reliability data of low level space-grade components. MaRS aims to be the first database to do this. The data in MaRS will be based on the hardware flown on the International Space Stations (ISS). The components on the ISS have a long history and are well documented, making them the perfect source. Currently, MaRS is a functioning excel workbook database; the backend is complete and only requires optimization. MaRS has been populated with all the assemblies and their components that are used on the ISS; the failures of these components are updated regularly. This project was a continuation on the efforts of previous intern groups. Once complete, R&M engineers working on future space flight missions will be able to quickly access failure and mass data on assemblies and components, allowing them to make important decisions and tradeoffs.

  7. CNC Turning Center Advanced Operations. Computer Numerical Control Operator/Programmer. 444-332.

    ERIC Educational Resources Information Center

    Skowronski, Steven D.; Tatum, Kenneth

    This student guide provides materials for a course designed to introduce the student to the operations and functions of a two-axis computer numerical control (CNC) turning center. The course consists of seven units. Unit 1 presents course expectations and syllabus, covers safety precautions, and describes the CNC turning center components, CNC…

  8. Researches Regarding The Circular Interpolation Algorithms At CNC Laser Cutting Machines

    NASA Astrophysics Data System (ADS)

    Tîrnovean, Mircea Sorin

    2015-09-01

    This paper presents an integrated simulation approach for studying the circular interpolation regime of CNC laser cutting machines. The circular interpolation algorithm is studied, taking into consideration the numerical character of the system. A simulation diagram, which is able to generate the kinematic inputs for the feed drives of the CNC laser cutting machine is also presented.

  9. RS Landers: Lunar lander

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The future of the U.S. space program outlined by President Bush calls for a permanently manned lunar base. A payload delivery system will be required to support the buildup and operation of that lunar base. In response to this goal, RS Landers developed a conceptual design of a self-unloading, unmanned, reusable lunar lander. The lander will deliver a 7000-kg payload, with the same dimensions as a space station logistics module, from low lunar orbit (LLO) to any location on the surface of the Moon.

  10. CNC water-jet machining and cutting center

    SciTech Connect

    Bartlett, D.C.

    1991-09-01

    CNC water-jet machining was investigated to determine the potential applications and cost-effectiveness that would result by establishing this capability in the engineering shops of Allied-Signal Inc., Kansas City Division (KCD). Both conductive and nonconductive samples were machined at KCD on conventional machining equipment (a three-axis conversational programmed mill and a wire electrical discharge machine) and on two current-technology water-jet machines at outside vendors. These samples were then inspected, photographed, and evaluated. The current-technology water-jet machines were not as accurate as the conventional equipment. The resolution of the water-jet equipment was only {plus minus}0.005 inch, as compared to {plus minus}0.0002 inch for the conventional equipment. The principal use for CNC water-jet machining would be as follows: Contouring to near finished shape those items made from 300 and 400 series stainless steels, titanium, Inconel, aluminum, glass, or any material whose fabrication tolerance is less than the machine resolution of {plus minus}0.005 inch; and contouring to finished shape those items made from Kevlar, rubber, fiberglass, foam, aluminum, or any material whose fabrication specifications allow the use of a machine with {plus minus}0.005 inch tolerance. Additional applications are possible because there is minimal force generated on the material being cut and because the water-jet cuts without generating dust. 12 figs.

  11. Prepolishing on a CNC platform with bound abrasive contour tools

    NASA Astrophysics Data System (ADS)

    Schoeffler, Adrienne E.; Gregg, Leslie L.; Schoen, John M.; Fess, Edward M.; Hakiel, Michael; Jacobs, Stephen D.

    2003-05-01

    Deterministic microgrinding (DMG) of optical glasses and ceramics is the commercial manufacturing process of choice to shape glass surfaces prior to final finishing. This process employs rigid bound matrix diamond tooling resulting in surface roughness values of 3-5μm peak to valley and 100-400nm rms, as well as mid-spatial frequency tool marks that require subsequent removal in secondary finishing steps. The ability to pre-polish optical surfaces within the grinding platform would reduce final finishing process times. Bound abrasive contour wheels containing cerium oxide, alumina or zirconia abrasives were constructed with an epoxy matrix. The effects of abrasive type, composition, and erosion promoters were examined for tool hardness (Shore D), and tested with commercial optical glasses in an Optipro CNC grinding platform. Metrology protocols were developed to examine tool wear and subsequent surface roughness. Work is directed to demonstrating effective material removal, improved surface roughness and cutter mark removal.

  12. Modeling of tool path for the CNC sheet cutting machines

    NASA Astrophysics Data System (ADS)

    Petunin, Aleksandr A.

    2015-11-01

    In the paper the problem of tool path optimization for CNC (Computer Numerical Control) cutting machines is considered. The classification of the cutting techniques is offered. We also propose a new classification of toll path problems. The tasks of cost minimization and time minimization for standard cutting technique (Continuous Cutting Problem, CCP) and for one of non-standard cutting techniques (Segment Continuous Cutting Problem, SCCP) are formalized. We show that the optimization tasks can be interpreted as discrete optimization problem (generalized travel salesman problem with additional constraints, GTSP). Formalization of some constraints for these tasks is described. For the solution GTSP we offer to use mathematical model of Prof. Chentsov based on concept of a megalopolis and dynamic programming.

  13. Design and performance of a small precision CNC turning machine

    SciTech Connect

    Donaldson, R.R.; Thompson, D.C.

    1986-02-26

    This paper describes the design of a CNC turning machine that is capable of machining workpieces up to 100 mm in diameter with a high contour accuracy and a very low surface roughness. Two nearly identical machines have been built and put into operation using this design, one for serial parts manufacture and the other for research into improving the accuracy of single-point machining; information based on this operational experience is also presented. The first machine has demonstrated an accuracy of 0.1 ..mu..m peak-to-valley on contoured workpieces, while the second machine has produced surface roughnesses of 1 nm rms in flat facing of electroless nickel with a diamond tool.

  14. H I Observations of the Asymptotic Giant Branch Star X Herculis: Discovery of an Extended Circumstellar Wake Superposed on a Compact High-velocity Cloud

    NASA Astrophysics Data System (ADS)

    Matthews, L. D.; Libert, Y.; Grard, E.; Le Bertre, T.; Johnson, M. C.; Dame, T. M.

    2011-02-01

    We report H I 21 cm line observations of the asymptotic giant branch (AGB) star X Her obtained with the Robert C. Byrd Green Bank Telescope (GBT) and the Very Large Array. We have unambiguously detected H I emission associated with the circumstellar envelope of the star, with a mass totaling M H I ? 2.1 10-3 M sun. The H I distribution exhibits a head-tail morphology, similar to those previously observed around the AGB stars Mira and RS Cnc. The tail is elongated along the direction of the star's space motion, with a total extent of >~ 6farcm0 (0.24 pc) in the plane of the sky. We also detect a systematic radial velocity gradient of ~6.5 km s-1 across the H I envelope. These results are consistent with the H I emission tracing a turbulent wake that arises from the motion of a mass-losing star through the interstellar medium (ISM). GBT mapping of a 2 2 region around X Her reveals that the star lies (in projection) near the periphery of a much larger H I cloud that also exhibits signatures of interaction with the ISM. The properties of the cloud are consistent with those of compact high-velocity clouds. Using 12CO J = 1-0 observations, we have placed an upper limit on its molecular gas content of N H2 < 1.3 1020 cm-2. Although the distance to the cloud is poorly constrained, the probability of a chance coincidence in position, velocity, and apparent position angle of space motion between X Her and the cloud is extremely small, suggesting a possible physical association. However, the large H I mass of the cloud (gsim2.4 M sun) and the blueshift of its mean velocity relative to X Her are inconsistent with an origin tied directly to ejection from the star.

  15. Shared and service-oriented CNC machining system for intelligent manufacturing process

    NASA Astrophysics Data System (ADS)

    Li, Yao; Liu, Qiang; Tong, Ronglei; Cui, Xiaohong

    2015-11-01

    To improve efficiency, reduce cost, ensure quality effectively, researchers on CNC machining have focused on virtual machine tool, cloud manufacturing, wireless manufacturing. However, low level of information shared among different systems is a common disadvantage. In this paper, a machining database with data evaluation module is set up to ensure integrity and update. An online monitoring system based on internet of things and multi-sensors "feel" a variety of signal features to "percept" the state in CNC machining process. A high efficiency and green machining parameters optimization system "execute" service-oriented manufacturing, intelligent manufacturing and green manufacturing. The intelligent CNC machining system is applied in production. CNC machining database effectively shares and manages process data among different systems. The prediction accuracy of online monitoring system is up to 98.8% by acquiring acceleration and noise in real time. High efficiency and green machining parameters optimization system optimizes the original processing parameters, and the calculation indicates that optimized processing parameters not only improve production efficiency, but also reduce carbon emissions. The application proves that the shared and service-oriented CNC machining system is reliable and effective. This research presents a shared and service-oriented CNC machining system for intelligent manufacturing process.

  16. Radio emission of cataclysmic variable stars

    NASA Technical Reports Server (NTRS)

    Fuerst, E.; Benz, A.; Hirth, W.; Geffert, M.; Kiplinger, A.

    1986-01-01

    Eight cataclysmic variable stars were observed at 6 cm wavelength using the Very Large Array (VLA). The objects were: CN-Ori, SS-Aur, YZ-Cnc, SU-Uma, Z-Cam, V603-Aql, EM-Cyg, and RZ-Sge. Most of these objects were in optical high stage, but none were detected beyond flux limits between 0.1 and 0.3 mJy.

  17. Systematics for checking geometric errors in CNC lathes

    NASA Astrophysics Data System (ADS)

    Araújo, R. P.; Rolim, T. L.

    2015-10-01

    Non-idealities presented in machine tools compromise directly both the geometry and the dimensions of machined parts, generating distortions in the project. Given the competitive scenario among different companies, it is necessary to have knowledge of the geometric behavior of these machines in order to be able to establish their processing capability, avoiding waste of time and materials as well as satisfying customer requirements. But despite the fact that geometric tests are important and necessary to clarify the use of the machine correctly, therefore preventing future damage, most users do not apply such tests on their machines for lack of knowledge or lack of proper motivation, basically due to two factors: long period of time and high costs of testing. This work proposes a systematics for checking straightness and perpendicularity errors in CNC lathes demanding little time and cost with high metrological reliability, to be used on factory floors of small and medium-size businesses to ensure the quality of its products and make them competitive.

  18. Continuous tone printing in silicone from CNC milled matrices

    NASA Astrophysics Data System (ADS)

    Hoskins, S.; McCallion, P.

    2014-02-01

    Current research at the Centre for Fine Print Research (CFPR) at the University of the West of England, Bristol, is exploring the potential of creating coloured pictorial imagery from a continuous tone relief surface. To create the printing matrices the research team have been using CNC milled images where the height of the relief image is dictated by creating a tone curve and then milling this curve into a series of relief blocks from which the image is cast in a silicone ink. A translucent image is cast from each of the colour matrices and each colour is assembled - one on top of another - resulting is a colour continuous tone print, where colour tone is created by physical depth of colour. This process is a contemporary method of continuous tone colour printing based upon the Nineteenth Century black and white printing process of Woodburytype as developed by Walter Bentley Woodbury in 1865. Woodburytype is the only true continuous tone printing process invented, and although its delicate and subtle surfaces surpassed all other printing methods at the time. The process died out in the late nineteenth century as more expedient and cost effective methods of printing prevailed. New research at CFPR builds upon previous research that combines 19th Century Photomechanical techniques with digital technology to reappraise the potential of these processes.

  19. Spatial augmented reality on industrial CNC-machines

    NASA Astrophysics Data System (ADS)

    Olwal, Alex; Gustafsson, Jonny; Lindfors, Christoffer

    2008-02-01

    In this work we present how Augmented Reality (AR) can be used to create an intimate integration of process data with the workspace of an industrial CNC (computer numerical control) machine. AR allows us to combine interactive computer graphics with real objects in a physical environment - in this case, the workspace of an industrial lathe. ASTOR is an autostereoscopic optical see-through spatial AR system, which provides real-time 3D visual feedback without the need for user-worn equipment, such as head-mounted displays or sensors for tracking. The use of a transparent holographic optical element, overlaid onto the safety glass, allows the system to simultaneously provide bright imagery and clear visibility of the tool and workpiece. The system makes it possible to enhance visibility of occluded tools as well as to visualize real-time data from the process in the 3D space. The graphics are geometrically registered with the workspace and provide an intuitive representation of the process, amplifying the user's understanding and simplifying machine operation.

  20. PSMA6 (rs2277460, rs1048990), PSMC6 (rs2295826, rs2295827) and PSMA3 (rs2348071) genetic diversity in Latvians, Lithuanians and Taiwanese

    PubMed Central

    Sjakste, Tatjana; Paramonova, Natalia; Wu, Lawrence Shi-Shin; Zemeckiene, Zivile; Sitkauskiene, Brigita; Sakalauskas, Raimundas; Wang, Jiu-Yao; Sjakste, Nikolajs

    2014-01-01

    PSMA6 (rs2277460, rs1048990), PSMC6 (rs2295826, rs2295827) and PSMA3 (rs2348071) genetic diversity was investigated in 1438 unrelated subjects from Latvia, Lithuania and Taiwan. In general, polymorphism of each individual locus showed tendencies similar to determined previously in HapMap populations. Main differences concern Taiwanese and include presence of rs2277460 rare allele A not found before in Asians and absence of rs2295827 rare alleles homozygotes TT observed in all other human populations. Observed patterns of SNPs and haplotype diversity were compatible with expectation of neutral model of evolution. Linkage disequilibrium between the rs2295826 and rs2295827 was detected to be complete in Latvians and Lithuanians (D´ = 1; r2 = 1) and slightly disrupted in Taiwanese (D´ = 0.978; r2 = 0.901). Population differentiation (FST statistics) was estimated from pairwise population comparisons of loci variability, five locus haplotypes and PSMA6 and PSMC6 two locus haplotypes. Latvians were significantly different from all Asians at each of 5 SNPs and from Lithuanians at the rs1048990 and PSMC6 loci. Lithuanian and Asian populations exhibited similarities at the PSMC6 loci and were different at the PSMA6 and PSMA3 SNPs. Considering five locus haplotypes all European populations were significantly different from Asian; Lithuanian population was different from both Latvian and CEU. Allele specific patterns of transcription factor binding sites and splicing signals were predicted in silico and addressed to eventual functionality of nucleotide substitutions and their potential to be involved in human genome evolution and geographical adaptation. Current study represents a novel step toward a systematic analysis of the proteasomal gene genetic diversity in human populations. PMID:25606411

  1. UVBY Photometry of the Magnetic Chemically Peculiar Stars HR 1297, 36 Aurigae, and HR 2722 and the Nonmagnetic Chemically Peculiar Stars HR 1576 and alpha CANCRI

    NASA Astrophysics Data System (ADS)

    Adelman, Saul J.; Brunhouse, Eric F.

    1998-11-01

    Differential Strömgren uvby photometric observations from the Four College Automated Photoelectric Telescope are presented for the magnetic CP stars HR 1297, 36 Aur, and HR 2722 and the nonmagnetic CP stars HR 1576 and alpha Cnc. Both the moderately rotating HR 1576, a mercury-manganese star, and alpha Cnc, a metallic-line star, are nonvariable. For HR 1297 we refined Winzer's period to 1.06457 days. Our period of 14.366 days for 36 Aur is an alias of Winzer's period and is in keeping with the sharp-lined nature of this star. We found a more accurate period of 2.31523 days for the low-amplitude variable HR 2722.

  2. RS3PE: Clinical and Research Development.

    PubMed

    Li, Hongbin; Altman, Roy D; Yao, Qingping

    2015-08-01

    Remitting seronegative symmetrical synovitis with pitting edema or RS3PE is a rare elderly-onset rheumatic syndrome. Although there are overlapping clinical manifestations between RS3PE, elderly-onset rheumatoid arthritis, and polymyalgia rheumatica, RS3PE has distinct characteristics. RS3PE can be associated with neoplasia and various rheumatic conditions, suggesting that it may be heterogeneous, and is considered as a paraneoplastic rheumatic disease. The pathogenesis of RS3PE may involve vascular endothelial growth factor and infection in RS3PE based upon limited data. Patients with RS3PE without concomitant malignancy respond well to small doses of glucocorticoids and carry good prognosis. PMID:26113011

  3. Rotational modulation and flares on RS CVn and BY Dra-type stars. I - Photometry and spot models for BY Dra, AU Mic, AR Lac, II Peg and V 711 Tau (= HR 1099)

    NASA Technical Reports Server (NTRS)

    Rodono, M.; Cutispoto, G.; Pazzani, V.; Catalano, S.; Byrne, P. B.

    1986-01-01

    Multicolor wide-band photometry of five active stars is presented. The observations were carried out at several places before, during and after the period of IUE observations for the purpose of determining the location, sizes, and evolution of photospheric spots at the time when chromospheric, transition region, and coronal activity data were obtained from UV and radio observations. II Peg, BY Dra, and AU Mic show fairly stable quasi-sinusoidal light curves, while AR Lac and V 711 Tau show double-peaked light curves. For V 711 Tau, a remarkable evolution of the spotted area extent and/or longitude distribution is found. Small, but definite color variations that are consistent with the cool spot hypothesis have also been detected for BY Dra, II Peg and V 711 Tau.

  4. An iterative learning control method with application for CNC machine tools

    SciTech Connect

    Kim, D.I.; Kim, S.

    1996-01-01

    A proportional, integral, and derivative (PID) type iterative learning controller is proposed for precise tracking control of industrial robots and computer numerical controller (CNC) machine tools performing repetitive tasks. The convergence of the output error by the proposed learning controller is guaranteed under a certain condition even when the system parameters are not known exactly and unknown external disturbances exist. As the proposed learning controller is repeatedly applied to the industrial robot or the CNC machine tool with the path-dependent repetitive task, the distance difference between the desired path and the actual tracked or machined path, which is one of the most significant factors in the evaluation of control performance, is progressively reduced. The experimental results demonstrate that the proposed learning controller can improve machining accuracy when the CNC machine tool performs repetitive machining tasks.

  5. The in-situ 3D measurement system combined with CNC machine tools

    NASA Astrophysics Data System (ADS)

    Zhao, Huijie; Jiang, Hongzhi; Li, Xudong; Sui, Shaochun; Tang, Limin; Liang, Xiaoyue; Diao, Xiaochun; Dai, Jiliang

    2013-06-01

    With the development of manufacturing industry, the in-situ 3D measurement for the machining workpieces in CNC machine tools is regarded as the new trend of efficient measurement. We introduce a 3D measurement system based on the stereovision and phase-shifting method combined with CNC machine tools, which can measure 3D profile of the machining workpieces between the key machining processes. The measurement system utilizes the method of high dynamic range fringe acquisition to solve the problem of saturation induced by specular lights reflected from shiny surfaces such as aluminum alloy workpiece or titanium alloy workpiece. We measured two workpieces of aluminum alloy on the CNC machine tools to demonstrate the effectiveness of the developed measurement system.

  6. Learning Control: Sense-Making, CNC Machines, and Changes in Vocational Training for Industrial Work

    ERIC Educational Resources Information Center

    Berner, Boel

    2009-01-01

    The paper explores how novices in school-based vocational training make sense of computerized numerical control (CNC) machines. Based on two ethnographic studies in Swedish schools, one from the early 1980s and one from 2006, it analyses change and continuity in the cognitive, social, and emotional processes of learning how to become a machine…

  7. CNC Turning Center Operations and Prove Out. Computer Numerical Control Operator/Programmer. 444-334.

    ERIC Educational Resources Information Center

    Skowronski, Steven D.

    This student guide provides materials for a course designed to instruct the student in the recommended procedures used when setting up tooling and verifying part programs for a two-axis computer numerical control (CNC) turning center. The course consists of seven units. Unit 1 discusses course content and reviews and demonstrates set-up procedures…

  8. 78 FR 50135 - CNC Development, Ltd., Exousia Advanced Materials, Inc., and South American Minerals, Inc.; Order...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-16

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE COMMISSION CNC Development, Ltd., Exousia Advanced Materials, Inc., and South American Minerals, Inc.; Order... current and accurate information concerning the securities of South American Minerals, Inc. because it...

  9. Basic CNC Operation. Training Workbook [and] Assessment and Training Guide [and] Hands-on Assessment.

    ERIC Educational Resources Information Center

    Anoka-Hennepin Technical Coll., Minneapolis, MN.

    This workbook is intended for students taking a course in basic computer numerical control (CNC) operation that was developed during a project to retrain defense industry workers at risk of job loss or dislocation because of conversion of the defense industry. The workbook contains daily training guides for each of the course's 13 sessions. Among…

  10. Technical and Symbolic Knowledge in CNC Machining: A Study of Technical Workers of Different Backgrounds.

    ERIC Educational Resources Information Center

    Martin, Laura M. W.; Beach, King

    Performances of 45 individuals with varying degrees of formal and informal training in machining and programming were compared on tasks designed to tap intellectual changes that may occur with the introduction of computer numerical control (CNC). Participants--30 machinists, 8 machine operators, and 7 engineers--were asked background questions and…

  11. Learning Control: Sense-Making, CNC Machines, and Changes in Vocational Training for Industrial Work

    ERIC Educational Resources Information Center

    Berner, Boel

    2009-01-01

    The paper explores how novices in school-based vocational training make sense of computerized numerical control (CNC) machines. Based on two ethnographic studies in Swedish schools, one from the early 1980s and one from 2006, it analyses change and continuity in the cognitive, social, and emotional processes of learning how to become a machine

  12. Development of a QFD-based expert system for CNC turning centre selection

    NASA Astrophysics Data System (ADS)

    Prasad, Kanika; Chakraborty, Shankar

    2015-10-01

    Computer numerical control (CNC) machine tools are automated devices capable of generating complicated and intricate product shapes in shorter time. Selection of the best CNC machine tool is a critical, complex and time-consuming task due to availability of a wide range of alternatives and conflicting nature of several evaluation criteria. Although, the past researchers had attempted to select the appropriate machining centres using different knowledge-based systems, mathematical models and multi-criteria decision-making methods, none of those approaches has given due importance to the voice of customers. The aforesaid limitation can be overcome using quality function deployment (QFD) technique, which is a systematic approach for integrating customers' needs and designing the product to meet those needs first time and every time. In this paper, the adopted QFD-based methodology helps in selecting CNC turning centres for a manufacturing organization, providing due importance to the voice of customers to meet their requirements. An expert system based on QFD technique is developed in Visual BASIC 6.0 to automate the CNC turning centre selection procedure for different production plans. Three illustrative examples are demonstrated to explain the real-time applicability of the developed expert system.

  13. Chemical crosslinking of acrylic acid to form biocompatible pH sensitive hydrogel reinforced with cellulose nanocrystals (CNC)

    NASA Astrophysics Data System (ADS)

    Lim, Lim Sze; Ahmad, Ishak; Lazim, Mohd Azwani Shah Mat; Amin, Mohd. Cairul Iqbal Mohd

    2014-09-01

    The purpose of this study is to produce a novel pH and temperature sensitive hydrogel, composed of poly(acrylic acid) (PAA) and cellulose nanocrystal (CNC). CNC was extracted from kenaf fiber through a series of alkali and bleaching treatments followed by acid hydrolysis. The PAA was then subjected to chemical cross-linking using the cross-linking agent (N,N-methylenebisacrylamide) with CNC entrapped in PAA matrix. The mixture was casted onto petri dish to obtain disc shape hydrogel. The effects of reaction conditions such as the ratio of PAA and CNC on the swelling behavior of the hydrogel obtained towards pH and temperature were studied. The obtained hydrogel was further subjected to different tests such swelling test for swelling behaviour at different pH and temperature along with scanning electron microscopy (SEM) for morphology analysis. The hydrogel obtained showed excellent pH sensitivity and obtained maximum swelling at pH 7. Besides that, hydrogel obtained showed significant increase in swelling ratio when temperature of swelling medium was increased from 25°C to 37°C. SEM micrograph showed that the pore size of the hydrogel decreases with increase of CNC content proving that the hydrogel structure became more rigid with addition of CNC. The PAA/CNC hydrogel with such excellent sensitivity towards pH and temperature can be developed further as drug carrier.

  14. Chemical crosslinking of acrylic acid to form biocompatible pH sensitive hydrogel reinforced with cellulose nanocrystals (CNC)

    SciTech Connect

    Lim, Lim Sze; Ahmad, Ishak; Lazim, Mohd Azwani Shah Mat; Amin, Mohd. Cairul Iqbal Mohd

    2014-09-03

    The purpose of this study is to produce a novel pH and temperature sensitive hydrogel, composed of poly(acrylic acid) (PAA) and cellulose nanocrystal (CNC). CNC was extracted from kenaf fiber through a series of alkali and bleaching treatments followed by acid hydrolysis. The PAA was then subjected to chemical cross-linking using the cross-linking agent (N,N-methylenebisacrylamide) with CNC entrapped in PAA matrix. The mixture was casted onto petri dish to obtain disc shape hydrogel. The effects of reaction conditions such as the ratio of PAA and CNC on the swelling behavior of the hydrogel obtained towards pH and temperature were studied. The obtained hydrogel was further subjected to different tests such swelling test for swelling behaviour at different pH and temperature along with scanning electron microscopy (SEM) for morphology analysis. The hydrogel obtained showed excellent pH sensitivity and obtained maximum swelling at pH 7. Besides that, hydrogel obtained showed significant increase in swelling ratio when temperature of swelling medium was increased from 25°C to 37°C. SEM micrograph showed that the pore size of the hydrogel decreases with increase of CNC content proving that the hydrogel structure became more rigid with addition of CNC. The PAA/CNC hydrogel with such excellent sensitivity towards pH and temperature can be developed further as drug carrier.

  15. CCD Photometric Study of the Contact Binary TX Cnc in the Young Open Cluster NGC 2632

    NASA Astrophysics Data System (ADS)

    Liu, Liang; Qian, Sheng-Bang; Boonrucksar, Soonthornthum; Zhu, Li-Ying; He, Jia-Jia; Yuan, J.-Z.

    2007-06-01

    TX Cnc is a member of the young open cluster NGC2632. In the present paper, four CCD epochs of light minimum and a complete V light curve of TX Cnc are presented. A period investigation based on all available photoelectric or CCD data showed that it is superimposed on a long-term increase (dP/dt=+3.9710-8) and weak evidence suggests that it includes a small-amplitude period oscillation (A3=0d.0028; T3=26.6yr). The light curves in the V band obtained in 2004 were analyzed with the 2003 version of the W-D code. It was shown that TX Cnc is an overcontact binary system with a degree of contact factor f=24.8%. The absolute parameters of the system were calculated: M1=1.3190.007M?, M2=0.6000.01M?; R1=1.280.19R?, R2=0.910.13R?. TX Cnc may be on the TRO-controlled stage of the evolutionary scheme proposed by Qian (2001a, b, 2003a), and may contain an invisible tertiary component (m3?0.097M?). If this is true, the tertiary component has played an important role in the formation and evolution of TX Cnc by removing angular momentum from the central system (Pribulla & Rucinski 2006). In this way the contact binary configuration can be formed in the shortlife time of a young open cluster via AML.

  16. Salyut-7 cosmonauts work with RS-17 and GSPS X-ray telescopes

    NASA Astrophysics Data System (ADS)

    Pokrovskiy, A.

    1984-11-01

    Two X-ray telescopes were tested aboard Salyut-7. The two instruments were the RS-17, and the GSPS. The X-ray sources, particularly in the Crab Nebulae and the Cygnus constellation, were observed spectrometrically. It is found that the two telescopes complement one another, the GSPS has high resolving power while the RS-17 receives the hard X-ray radiation. It is suggested that X-ray radiation accompanies the final stage of the evolution of certain stars and the processes which lead to the death of giant stars.

  17. Heavy elements in the ultraviolet spectra of Ap stars.

    NASA Astrophysics Data System (ADS)

    Severnyj, A. B.

    Heavy element abundances of Ap stars were determined using ultraviolet spectra obtained from the photoelectric scanner on the Astron space telescope. The procedure by which the observed spectral data were obtained for the individual sections of the spectrum scanned is described. The observed data were analyzed using model atmospheres and known oscillator strengths. In this way, a lead abundance ≡100 times solar, and a tungsten abundance of more than 102times solar were obtained in κ CnC. Anomalous abundances (105solar) were also obtained for uranium and thorium in 73 Dra, where the abundance of lead and tungsten is about the same as in κ Cnc. The lead abundance found in several stars rules out the s-process as a possible source for the formation of this element from the iron-peak elements.For the Russian original see 42.114.093.

  18. 76 FR 39156 - C&NC Railroad, LLC-Lease Renewal Exemption-Norfolk Southern Railway Company

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-05

    ... each car interchanged with NSR. C&NC notes that NSR initially proposed a fixed rental payment with no... earn a lower rental payment so it would be able to invest in improvements on the leased lines...

  19. PLLA-grafted cellulose nanocrystals: Role of the CNC content and grafting on the PLA bionanocomposite film properties.

    PubMed

    Lizundia, Erlantz; Fortunati, Elena; Dominici, Franco; Vilas, José Luis; León, Luis Manuel; Armentano, Ilaria; Torre, Luigi; Kenny, Josè M

    2016-05-20

    Cellulose nanocrystals (CNC), extracted from microcrystalline cellulose by acid hydrolysis, were grafted by ring opening polymerization of l-Lactide initiated from the hydroxyl groups available at their surface and two different CNC:l-lactide ratios (20:80 and 5:95) were obtained. The resulting CNC-g-PLLA nanohybrids were incorporated in poly(lactic acid) (PLA) matrix by an optimized extrusion process at two different content (1wt.% and 3wt.%) and obtained bionanocomposite films were characterized by thermal, mechanical, optical and morphological properties. Thermal analysis showed CNC grafted with the higher ratio of lactide play a significant role as a nucleating agent. Moreover, they contribute to a significant increase in the crystallization rate of PLA, and the best efficiency was revealed with 3wt.% of CNC-g-PLLA. This effect was confirmed by the increased in Young's modulus, suggesting the CNC graft ratio and content contribute significantly to the good dispersion in the matrix, positively affecting the final bionanocomposite properties. PMID:26917380

  20. Vision-based on-machine measurement for CNC machine tool

    NASA Astrophysics Data System (ADS)

    Xia, Ruixue; Han, Jiang; Lu, Rongsheng; Xia, Lian

    2015-02-01

    A vision-based on-machine measurement system (OMM) was developed to improve manufacturing effectiveness. It was based on a visual probe to enable the CNC machine tool itself to act as a coordinate measuring machine (CMM) to inspect a workpiece. The proposed OMM system was composed of a visual probe and two software modules: computer-aided inspection planning (CAIP) module and measurement data processing (MDP) module. The auto-focus function of the visual probe was realized by using astigmatic method. The CAIP module was developed based on a CAD development platform with Open CASCADE as its kernel. The MDP module includes some algorithms for determination of inspection parameters, for example, the chamfered hole was measured through focus variation. The entire system was consequently verified on a CNC milling machine.

  1. Thread milling on N/C and CNC milling machines. Final report

    SciTech Connect

    Ashbaugh, F.A.; Murry, K.R.

    1985-12-01

    A unique thread-cutting tool design has been developed which permits threading of internal or external features; right- or left-hand threads; and standard, metric, or special pitches within a given size range without changing tools. One of the major advantages of the technique is the ability to produce small threads on N/C and CNC milling manchines. This study presents results showing fabrication of quality threads as small as number 0-80 in selected materials.

  2. Comparison between predicted and actual accuracies for an Ultra-Precision CNC measuring machine

    SciTech Connect

    Thompson, D.C.; Fix, B.L.

    1995-05-30

    At the 1989 CIRP annual meeting, we reported on the design of a specialized, ultra-precision CNC measuring machine, and on the error budget that was developed to guide the design process. In our paper we proposed a combinatorial rule for merging estimated and/or calculated values for all known sources of error, to yield a single overall predicted accuracy for the machine. In this paper we compare our original predictions with measured performance of the completed instrument.

  3. Polymorphisms in TP53 (rs1042522), p16 (rs11515 and rs3088440) and NQO1 (rs1800566) genes in Thai cervical cancer patients with HPV 16 infection.

    PubMed

    Chansaenroj, Jira; Theamboonlers, Apiradee; Junyangdikul, Pairoj; Swangvaree, Sukumarn; Karalak, Anant; Chinchai, Teeraporn; Poovorawan, Yong

    2013-01-01

    The risk of cervical cancer development in women infected with HPV varies in relation to the individual host's genetic makeup. Many studies on polymorphisms as genetic factors have been aimed at analyzing associations with cervical cancer. In this study, single nucleotide polymorphisms (SNPs) in 3 genes were investigated in relation to cervical cancer progression in HPV16 infected women with lesions. Two thousand cervical specimens were typed by PCR sequencing methods for TP53 (rs1042522), p16 (rs11515 and rs3088440) and NQO1 (rs1800566). Ninety two HPV16 positive cases and thirty two normal cases were randomly selected. Analysis of TP53 (rs1042522) showed a significantly higher frequency in cancer samples (OR=1.22, 95%CI=1.004-1.481, p-value=0.016) while differences in frequency were not significant within each group (p-value=0.070). The genotype distributions of p16 (rs11515 and rs3088440) and NQO1 (rs1800566) did not show any significantly higher frequency in cancer samples (p-value=0.106, 0.675 and 0.132, respectively) or within each group (p-value=0.347, 0.939 and 0.111, respectively). The results indicated that the polymorphism in TP53 (rs1042522) might be associated with risk of cervical cancer development in HPV16 infected women. Further studies of possible mechanisms of influence on cervical cancer development would be useful to manage HPV infected patients. PMID:23534750

  4. A Three Dimensional Picture of RS CVN Stellar Atmospheres

    NASA Astrophysics Data System (ADS)

    Linsky, Jeffrey L.

    The ROSAT all-sky survey provides a unique opportunity to study an RS CVn system simultaneously at x-ray, EUV, UV, optical, and radio wavelengths at many phases throughout an orbital period. ROSAT can detect the x-ray flux of each candidate system during each 30 second viewing 16 times per day for at least 2 days. We request a block of 7 IUE shifts to obtain NEAR SIMULTANEOUS emission line fluxes (SWP-LO) and Mg IT line profiles (LWP-HI), and we will obtain contemporaneous optical photometry and spectroscopy and VLA radio fluxes (3.6, 6, and 20 cm). one objective of this PROPOSAL is to obtain the FIRST 3-D MODEL OF THE INHOMOGENEOUS PHOTOSPHERE, CHROMOSPHERE, AND CORONA OF A STAR OTHER THAN THE SUN. We will use optical photometry and spectroscopy to map the spotted photospheres of each star, and the Mg II line profiles to DOPPLERIMAGE their chromospheres, to determine the location, size, and surface flux of the active regions. We will then use the time variation of the UV emission line and x-ray fluxes to determine what fluxes are due to the quiet and active regions separately. These data will provide SURFACE FLUXES for the quiet and active regions separately. We will then will model BOTH REGIONS independently using an emission measure analysis. We will also model any flares observed. The second part of the program will be a simultaneous UV/X-ray SURVEY with the objective of DETERMINING THE RANGE OF PHYSICAL MODELS APPLICABLE TO THE CHROMOSPHERES AND CORONAE OF RS CVN SYSTEMS. We propose to obtain emission line fluxes (SWP-LO) and Mg II line profiles (LWP-HI) of all bright RS CVns observed by ROSAT from mid-July through September 1990 that meet the IUE observing constraints. About 17 systems in the Strassmeier catalog will likely be observed during this period. While many RS CVn systems have been observed separately by IUE and x-ray satellites, SIMULTANEOUS UV and x-ray observations are required to model these spatially inhomogenous and timevariable systems. This research program and the ROSAT RS CVn survey will constitute most of the data for the Ph.D. Thesis of the Lead Investigator, Anthony Veale.

  5. Variability in the super-Earth 55 Cnc e

    NASA Astrophysics Data System (ADS)

    Demory, Brice-Olivier; Gillon, Michael; Madhusudhan, Nikku; Queloz, Didier

    2016-01-01

    Considerable progress has been made in recent years in observations of atmospheric signatures of giant exoplanets, but processes in rocky exoplanets remain largely unknown due to major challenges in observing small planets. Numerous efforts to observe spectra of super-Earths, exoplanets with masses of 1-10 Earth masses, have thus far revealed only featureless spectra. In this paper, we report a 4σ detection of variability in the dayside thermal emission from the transiting super-Earth 55 Cancri e. Dedicated space-based monitoring of the planet in the mid-infrared over eight eclipses revealed the thermal emission from its dayside atmosphere varying by a factor of 3.7 between 2012 and 2013. The amplitude and trend of the variability are not explained by potential influence of star spots or by local thermal or compositional changes in the atmosphere over the short span of the observations. The possibility of large-scale surface activity due to strong tidal interactions possibly similar to Io, or the presence of circumstellar/circumplanetary material appear plausible and motivate future long-term monitoring of the planet.

  6. H I OBSERVATIONS OF THE ASYMPTOTIC GIANT BRANCH STAR X HERCULIS: DISCOVERY OF AN EXTENDED CIRCUMSTELLAR WAKE SUPERPOSED ON A COMPACT HIGH-VELOCITY CLOUD

    SciTech Connect

    Matthews, L. D.; Johnson, M. C.; Libert, Y.; Gerard, E.; Le Bertre, T.; Dame, T. M.

    2011-02-15

    We report H I 21 cm line observations of the asymptotic giant branch (AGB) star X Her obtained with the Robert C. Byrd Green Bank Telescope (GBT) and the Very Large Array. We have unambiguously detected H I emission associated with the circumstellar envelope of the star, with a mass totaling M{sub HI} {approx} 2.1 x 10{sup -3} M{sub sun}. The H I distribution exhibits a head-tail morphology, similar to those previously observed around the AGB stars Mira and RS Cnc. The tail is elongated along the direction of the star's space motion, with a total extent of {approx}> 6.'0 (0.24 pc) in the plane of the sky. We also detect a systematic radial velocity gradient of {approx}6.5 km s{sup -1} across the H I envelope. These results are consistent with the H I emission tracing a turbulent wake that arises from the motion of a mass-losing star through the interstellar medium (ISM). GBT mapping of a 2{sup 0} x 2{sup 0} region around X Her reveals that the star lies (in projection) near the periphery of a much larger H I cloud that also exhibits signatures of interaction with the ISM. The properties of the cloud are consistent with those of compact high-velocity clouds. Using {sup 12}CO J = 1-0 observations, we have placed an upper limit on its molecular gas content of N{sub H2} < 1.3 x 10{sup 20} cm{sup -2}. Although the distance to the cloud is poorly constrained, the probability of a chance coincidence in position, velocity, and apparent position angle of space motion between X Her and the cloud is extremely small, suggesting a possible physical association. However, the large H I mass of the cloud ({approx}>2.4 M{sub sun}) and the blueshift of its mean velocity relative to X Her are inconsistent with an origin tied directly to ejection from the star.

  7. Documentation for the machine-readable version of the Catalogue of Nearby Stars, edition 1969

    NASA Technical Reports Server (NTRS)

    Warren, W. H., Jr.

    1982-01-01

    The Catalogue of Nearby Stars, Edition 1969 (Gliese 1969) contains a number of modifications and additions to the 1957 catalog. It should be mentioned that the 1969 edition lists: (1) all 915 stars of the first edition, even though newer parallaxes place some of the stars below the catalog limit; (2) almost all known stars having trigonometric parallaxes or = 0.045 deg, although in some cases the mean values of trigonometric and spectral or photometric parallaxes are or = 0.045 deg. Pleiades stars and the carbon star X Cnc have been omitted; and (3) all stars with mean (resulting) parallaxes or = 0.045 deg. The resulting catalog contains 1529 single stars and systems with a total of 1890 components (not including spectroscopic and astrometric companions). The machine-readable version of the catalog is described. It is intended to enable users to read and process the data without problems or guesswork.

  8. IUE spectra of a flare in the RS Canum Venaticorum-type system UX Arietis

    NASA Technical Reports Server (NTRS)

    Simon, T.; Linsky, J. L.; Schiffer, F. H., III

    1980-01-01

    IUE spectra of UX Ari obtained during the large flare of 1979 January 1 exhibit chromospheric and transition-region emission-line fluxes about 2.5 and 5.5 times brighter than quiescent fluxes, respectively, and up to 1400 times brighter than the quiet sun. A high-dispersion spectrum of the 2000-3000 A region exhibits enhanced Fe II emission, which is probably associated mainly with the K0 IV star, and enhanced Mg II emission with asymmetric wings extending to +475 km/s. These line wings are interpreted as evidence for mass flow from the K0 IV star to the G5 V star. A speculative scenario of major long-lived RS CVn flares is proposed in which the component stars have very large corotating flux tubes, which occasionally interact. Magnetic reconnection results in flux tubes that temporarily connect the two stars.

  9. Lack of association between TESPA1 gene polymorphisms (rs1801876, rs2171497, rs4758994, and rs997173) and ankylosing spondylitis in a Chinese population.

    PubMed

    Liu, Si; Liu, Li; Wu, Shanshan; Yang, Ting; Pan, Faming; Laslett, Laura; Xia, Guo; Hu, Yanting; Fan, Dazhi; Ding, Ning; Xu, Shengqian; Cai, Guoqi; Wang, Li; Xin, Lihong

    2014-12-01

    We investigated whether TESPA1 gene polymorphisms were associated with increased risk of developing ankylosing spondylitis (AS). We also studied whether TESPA1 gene interacts with environmental factors. A total of 494 patients with AS and 478 matched healthy controls were genotyped for four SNPs (rs1801876, rs2171497, rs4758994, and rs997173) in the TESPA1 gene. We found no evidence of association between these SNPs and AS susceptibility, and between their haplotypes and the disease. But, patients with rs1801876 GA, GG, and AA genotypes had significantly different Bath Ankylosing Spondylitis Functional Index (BASFI) scores (p = 0.023). There were significantly different visual analogue scale (VAS) night pain assessment scores (p = 0.040) and BASFI scores (p = 0.023) among different genotypes at rs2171497 locus. There were also significantly different chest expansion scores (p = 0.042) and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) scores (p = 0.014) among different genotypes at rs997173 locus. For multiple testing, Bonferroni correction was performed. After Bonferroni correction, clinical characteristics of these three loci showed association between different genotype groups. These findings indicated that the TESPA1 gene is not involved in AS genetic predisposition in the Han Chinese population; however, it may play an important role in the clinical characteristics of AS. PMID:24893580

  10. The effect of the model posture on the forming quality in the CNC incremental forming

    NASA Astrophysics Data System (ADS)

    Zhu, H.; Zhang, W.; Bai, J. L.; Yu, C.; Xing, Y. F.

    2015-12-01

    Sheet rupture caused by a sheet metal thickness non-uniformity persists in CNC (Computer Numerical Control) incremental forming. Because the forming half cone angle is determined by the orientation of the model to be formed, so is the sheet metal's uniformity. The finite element analysis models for the two kinds of the postures of the model were established, and the digital simulation was conducted by using the ANSYS/LA-DYNA software. The effect of the model's posture on the sheet thickness distribution and the sheet thickness thinning rate were studied by comparing the simulation results of two kinds of the finite elements analyzes.

  11. Accurate identification and compensation of geometric errors of 5-axis CNC machine tools using double ball bar

    NASA Astrophysics Data System (ADS)

    Lasemi, Ali; Xue, Deyi; Gu, Peihua

    2016-05-01

    Five-axis CNC machine tools are widely used in manufacturing of parts with free-form surfaces. Geometric errors of machine tools have significant effects on the quality of manufactured parts. This research focuses on development of a new method to accurately identify geometric errors of 5-axis CNC machines, especially the errors due to rotary axes, using the magnetic double ball bar. A theoretical model for identification of geometric errors is provided. In this model, both position-independent errors and position-dependent errors are considered as the error sources. This model is simplified by identification and removal of the correlated and insignificant error sources of the machine. Insignificant error sources are identified using the sensitivity analysis technique. Simulation results reveal that the simplified error identification model can result in more accurate estimations of the error parameters. Experiments on a 5-axis CNC machine tool also demonstrate significant reduction in the volumetric error after error compensation.

  12. Finger milling-cutter CNC generating hypoid pinion tooth surfaces based on modified-roll method and machining simulation

    NASA Astrophysics Data System (ADS)

    Li, Genggeng; Deng, Xiaozhong; Wei, Bingyang; Lei, Baozhen

    2011-05-01

    The two coordinate systems of cradle-type hypoid generator and free-form CNC machine tool by application disc milling-cutter to generate hypoid pinion tooth surfaces based on the modified-roll method were set up, respectively, and transformation principle and method for machine-tool settings between the two coordinate systems was studied. It was presented that finger milling-cutter was mounted on imagined disc milling-cutter and its motion was controlled directly by CNC shafts to replace disc milling-cutter blades effective cutting motion. Finger milling-cutter generation accomplished by ordered circular interpolation was determined, and interpolation center, starting and ending were worked out. Finally, a hypoid pinion was virtually machined by using CNC machining simulation software VERICUT.

  13. Finger milling-cutter CNC generating hypoid pinion tooth surfaces based on modified-roll method and machining simulation

    NASA Astrophysics Data System (ADS)

    Li, Genggeng; Deng, Xiaozhong; Wei, Bingyang; Lei, Baozhen

    2010-12-01

    The two coordinate systems of cradle-type hypoid generator and free-form CNC machine tool by application disc milling-cutter to generate hypoid pinion tooth surfaces based on the modified-roll method were set up, respectively, and transformation principle and method for machine-tool settings between the two coordinate systems was studied. It was presented that finger milling-cutter was mounted on imagined disc milling-cutter and its motion was controlled directly by CNC shafts to replace disc milling-cutter blades effective cutting motion. Finger milling-cutter generation accomplished by ordered circular interpolation was determined, and interpolation center, starting and ending were worked out. Finally, a hypoid pinion was virtually machined by using CNC machining simulation software VERICUT.

  14. Ares V and RS-68B

    NASA Technical Reports Server (NTRS)

    Creech, Steve; Taylor, Jim; Bellamy, Scott; Kuck, Fritz

    2008-01-01

    Ares V is the heavy lift vehicle NASA is designing for lunar and other space missions. It has significantly more lift capability than the Saturn V vehicle used for the Apollo missions to the moon. Ares V is powered by two recoverable 5.5 segment solid rocket boosters and six RS-68B engines on the core stage. The upper stage, designated as the Earth Departure Stage, is powered by a single J-2X engine. This paper provides an overview of the Ares V vehicle and the RS-68B engine, an upgrade to the Pratt & Whitney Rocketdyne RS-68 engine developed for the Delta IV vehicle.

  15. Search for RS-gravitons at CDF

    SciTech Connect

    Strologas, John; /New Mexico U.

    2011-09-01

    We present a search for Randall-Sundrum (RS) gravitons decaying to diphotons or dielectrons or dimuons, performed with the CDF II detector and using up to 5.7 fb{sup -1} of integrated luminosity. The respective mass spectra are consistent with the ones expected by the standard model. For the RS-model parameter k/{bar M}{sub Pl} = 0.1, RS-gravitons with mass less than 1111 GeV/c{sup 2} are excluded at 95% CL.

  16. 40 CFR 180.1114 - Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS; exemptions from the requirement of a tolerance... Tolerances § 180.1114 Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae... A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS are exempted from the......

  17. Comparison of Vaisala radiosondes RS41 and RS92 at the ARM Southern Great Plains Site

    NASA Astrophysics Data System (ADS)

    Jensen, M. P.; Holdridge, D.; Survo, P.; Lehtinen, R.; Baxter, S.; Toto, T.; Johnson, K. L.

    2015-11-01

    In the fall of 2013, the Vaisala RS41-SG (4th generation) radiosonde was introduced as a replacement for the RS92-SGP radiosonde with improvements in measurement accuracy of profiles of atmospheric temperature, humidity and pressure. In order to help characterize these improvements, an intercomparison campaign was undertaken at the US Department of Energy's Atmospheric Radiation Measurement (ARM) Facility site in north Central Oklahoma USA. During 3-8 June 2014, a total of 20 twin-radiosonde flights were performed in a variety of atmospheric conditions representing typical midlatitude continental summertime conditions. The results suggest that the RS92 and RS41 measurements generally agree within manufacturer specified tolerances with notable exceptions when exiting liquid cloud layers where the "wet bulbing" effect is mitigated in the RS41 observations. The RS41 measurements also appear to show a smaller impact from solar heating. These results suggest that the RS41 does provide important improvements, particularly in cloudy conditions, but under most observational conditions the RS41 and RS92 measurements agree within the manufacturer specified limits and so a switch to RS41 radiosondes will have little impact on long-term observational records.

  18. Comparison of Vaisala radiosondes RS41 and RS92 at the ARM Southern Great Plains Site

    SciTech Connect

    Jensen, M. P.; Holdridge, D.; Survo, P.; Lehtinen, R.; Baxter, S.; Toto, T.; Johnson, K. L.

    2015-11-02

    In the fall of 2013, the Vaisala RS41-SG (4th generation) radiosonde was introduced as a replacement for the RS92-SGP radiosonde with improvements in measurement accuracy of profiles of atmospheric temperature, humidity and pressure. Thus, in order to help characterize these improvements, an intercomparison campaign was undertaken at the US Department of Energy's Atmospheric Radiation Measurement (ARM) Facility site in north Central Oklahoma USA. During 3–8 June 2014, a total of 20 twin-radiosonde flights were performed in a variety of atmospheric conditions representing typical midlatitude continental summertime conditions. The results suggest that the RS92 and RS41 measurements generally agree within manufacturer specified tolerances with notable exceptions when exiting liquid cloud layers where the "wet bulbing" effect is mitigated in the RS41 observations. The RS41 measurements also appear to show a smaller impact from solar heating. These results suggest that the RS41 does provide important improvements, particularly in cloudy conditions, but under most observational conditions the RS41 and RS92 measurements agree within the manufacturer specified limits and so a switch to RS41 radiosondes will have little impact on long-term observational records.

  19. Comparison of Vaisala radiosondes RS41 and RS92 at the ARM Southern Great Plains Site

    DOE PAGESBeta

    Jensen, M. P.; Holdridge, D.; Survo, P.; Lehtinen, R.; Baxter, S.; Toto, T.; Johnson, K. L.

    2015-11-02

    In the fall of 2013, the Vaisala RS41-SG (4th generation) radiosonde was introduced as a replacement for the RS92-SGP radiosonde with improvements in measurement accuracy of profiles of atmospheric temperature, humidity and pressure. Thus, in order to help characterize these improvements, an intercomparison campaign was undertaken at the US Department of Energy's Atmospheric Radiation Measurement (ARM) Facility site in north Central Oklahoma USA. During 3–8 June 2014, a total of 20 twin-radiosonde flights were performed in a variety of atmospheric conditions representing typical midlatitude continental summertime conditions. The results suggest that the RS92 and RS41 measurements generally agree within manufacturermore » specified tolerances with notable exceptions when exiting liquid cloud layers where the "wet bulbing" effect is mitigated in the RS41 observations. The RS41 measurements also appear to show a smaller impact from solar heating. These results suggest that the RS41 does provide important improvements, particularly in cloudy conditions, but under most observational conditions the RS41 and RS92 measurements agree within the manufacturer specified limits and so a switch to RS41 radiosondes will have little impact on long-term observational records.« less

  20. Role of redoximiRs in fibrogenesis.

    PubMed

    Fierro-Fernández, Marta; Miguel, Verónica; Lamas, Santiago

    2016-04-01

    Fibrosis can be defined as an excessive accumulation of extracellular matrix (ECM) components, ultimately leading to stiffness, scarring and devitalized tissue. MicroRNAs (miRNAs) are short, 19-25 nucleotides (nt), non-coding RNAs involved in the post-transcriptional regulation of gene expression. Recently, miRNAs have also emerged as powerful regulators of fibrotic processes and have been termed "fibromiRs". Oxidative stress represents a self-perpetuating mechanism in fibrogenesis. MiRNAs can also influence the expression of genes responsible for the generation of reactive oxygen species (ROS) and antioxidant defence and are termed "redoximiRs". Here, we review the current knowledge of mechanisms by which "redoximiRs" regulate fibrogenesis. This new set of miRNAs may be called "redoxifibromiRs". PMID:26654978

  1. The resonance line of B II in IUE spectra of chemically peculiar stars

    NASA Technical Reports Server (NTRS)

    Leckrone, D. S.

    1981-01-01

    A description is presented of high-dispersion spectroscopic observations of eight chemically peculiar stars including Kappa Cnc and Mu Lep, and of one normal comparison star, Nu Cap, in the vicinity of 1362 A. The reported data were obtained with the International Ultraviolet Explorer during the first 15 months of its operation. The initial reduction of the data, which were originally described in a qualitative summary by Leckrone (1980), was affected by a serious error in the calibration of the instrument's intensity transfer function. This error has been corrected in the currently presented data. The results of spectrum syntheses of the 1362 A feature are also described for several of the stars.

  2. [Characteristic of the Genetic Variability of Four Polymorphic Variants (rs2069705, rs17880053, rs11126176, and rs804271) in Representative Samples of Indigenous and Alien Populations of Siberia].

    PubMed

    Kucher, A N; Babushkina, N P; Kulish, E V; Makeeva, O A; Bragina, E Yu; Goncharova, I A; Eremina, E R; Puzyrev, V P

    2015-08-01

    The variability of potentially important functional polymorphic variants rs2069705 (5'UTR of the IFNG gene), rs17880053 (near 5'UTR of the IFNGR2), rs11126176 (LOC100287361 pseudogene), and rs804271 (near 5'UTR of the NEIL2 gene) was characterized in representatives of four ethnic groups living in the Siberian region. These ethnic groups included three indigenous Mongoloid ethnic groups (Yakuts, the residents of the Republic of Sakha (Yakutia), Tuvinians from the Republic of Tuva, and Buryats from the Republic Buryatia) and the alien Russian population. All of the examined variants were polymorphic. The frequency of the rs2069705 allele C in Russians was 0.5833, while it was in a range from 0.7842 to 0.8967 in representatives of the indigenous populations. The frequency of rs17880053 deletion was 0.8073 in Russians and from 0.4474 to 0.5521 in the indigenous ethnic groups. The frequency of the rs11126176 allele A was equal to 0.5398 in Russians but was recorded with lower frequencies in indigenous ethnic groups (from 0.2722 to 0.4551). The frequency of the rs804271 allele Gwas 0.5215 in Russians and from 0.2527 to 0.4022 indigenous ethnic groups. With respect to the genotype structure, the alien Russian population was considerably distanced from indigenous Mongoloid populations. Specifically, the genetic distance was 0.0742 between Russians and Yakuts, 0.1365 between Russians and Tuvinians, and 0.1433 between Russians and Buryats. Among the Mongoloid indigenous ethnic groups of Siberia, Tuvinians and Yakuts were the most distant from each other (0.0262). The genetic distance was equal to 0.0151 between Yakuts and Buryats and 0.0127 between Buryats and Tuvinians. PMID:26601495

  3. Novel CNC Grinding Process Control for Nanometric Surface Roughness for Aspheric Space Optical Surfaces

    NASA Astrophysics Data System (ADS)

    Han, Jeong-Yeol; Kim, Sug-Whan; Kim, Geon-Hee; Kim, Dae-Wook; Kim, Ju-Whan

    2004-06-01

    Optics fabrication process for precision space optical parts includes bound abrasive grinding, loose abrasive lapping and polishing. The traditional bound abrasive grinding with bronze bond cupped diamond wheel leaves the machine marks of about 20 μm rms in height and the subsurface damage of about 1 μm rms in height to be removed by subsequent loose abrasive lapping. We explored an efficient quantitative control of precision CNC grinding. The machining parameters such as grain size, work-piece rotation speed and feed rate were altered while grinding the work-piece surfaces of 20-100 mm in diameter. The input grinding variables and the resulting surface quality data were used to build grinding prediction models using empirical and multi-variable regression analysis. The effectiveness of such grinding prediction models was then examined by running a series of precision CNC grinding operation with a set of controlled input variables and predicted output surface! quality indicators. The experiment achieved the predictability down to ±20 nm in height and the surface roughness down to 36 nm in height. This study contributed to improvement of the process efficiency reaching directly the polishing and figuring process without the need for the loose abrasive lapping stage.

  4. AT Cnc: A Second Dwarf Nova with a Classical Nova Shell

    NASA Astrophysics Data System (ADS)

    Shara, Michael M.; Mizusawa, Trisha; Wehinger, Peter; Zurek, David; Martin, Christopher D.; Neill, James D.; Forster, Karl; Seibert, Mark

    2012-10-01

    We are systematically surveying all known and suspected Z Cam-type dwarf novae for classical nova shells. This survey is motivated by the discovery of the largest known classical nova shell, which surrounds the archetypal dwarf nova Z Camelopardalis. The Z Cam shell demonstrates that at least some dwarf novae must have undergone classical nova eruptions in the past, and that at least some classical novae become dwarf novae long after their nova thermonuclear outbursts, in accord with the hibernation scenario of cataclysmic binaries. Here we report the detection of a fragmented "shell," 3 arcmin in diameter, surrounding the dwarf nova AT Cancri. This second discovery demonstrates that nova shells surrounding Z Cam-type dwarf novae cannot be very rare. The shell geometry is suggestive of bipolar, conical ejection seen nearly pole-on. A spectrum of the brightest AT Cnc shell knot is similar to that of the ejecta of the classical nova GK Per, and of Z Cam, dominated by [N II] emission. Galaxy Evolution Explorer FUV imagery reveals a similar-sized, FUV-emitting shell. We determine a distance of 460 pc to AT Cnc, and an upper limit to its ejecta mass of ~5 × 10-5 M ⊙, typical of classical novae.

  5. Step-and-Repeat Nanoimprint-, Photo- and Laser Lithography from One Customised CNC Machine

    NASA Astrophysics Data System (ADS)

    Greer, Andrew IM; Della-Rosa, Benoit; Khokhar, Ali Z.; Gadegaard, Nikolaj

    2016-03-01

    The conversion of a computer numerical control machine into a nanoimprint step-and-repeat tool with additional laser- and photolithography capacity is documented here. All three processes, each demonstrated on a variety of photoresists, are performed successfully and analysed so as to enable the reader to relate their known lithography process(es) to the findings. Using the converted tool, 1 cm2 of nanopattern may be exposed in 6 s, over 3300 times faster than the electron beam equivalent. Nanoimprint tools are commercially available, but these can cost around 1000 times more than this customised computer numerical control (CNC) machine. The converted equipment facilitates rapid production and large area micro- and nanoscale research on small grants, ultimately enabling faster and more diverse growth in this field of science. In comparison to commercial tools, this converted CNC also boasts capacity to handle larger substrates, temperature control and active force control, up to ten times more curing dose and compactness. Actual devices are fabricated using the machine including an expanded nanotopographic array and microfluidic PDMS Y-channel mixers.

  6. Investigation on Effect of Material Hardness in High Speed CNC End Milling Process

    PubMed Central

    Dhandapani, N. V.; Thangarasu, V. S.; Sureshkannan, G.

    2015-01-01

    This research paper analyzes the effects of material properties on surface roughness, material removal rate, and tool wear on high speed CNC end milling process with various ferrous and nonferrous materials. The challenge of material specific decision on the process parameters of spindle speed, feed rate, depth of cut, coolant flow rate, cutting tool material, and type of coating for the cutting tool for required quality and quantity of production is addressed. Generally, decision made by the operator on floor is based on suggested values of the tool manufacturer or by trial and error method. This paper describes effect of various parameters on the surface roughness characteristics of the precision machining part. The prediction method suggested is based on various experimental analysis of parameters in different compositions of input conditions which would benefit the industry on standardization of high speed CNC end milling processes. The results show a basis for selection of parameters to get better results of surface roughness values as predicted by the case study results. PMID:26881267

  7. Step-and-Repeat Nanoimprint-, Photo- and Laser Lithography from One Customised CNC Machine.

    PubMed

    Greer, Andrew Im; Della-Rosa, Benoit; Khokhar, Ali Z; Gadegaard, Nikolaj

    2016-12-01

    The conversion of a computer numerical control machine into a nanoimprint step-and-repeat tool with additional laser- and photolithography capacity is documented here. All three processes, each demonstrated on a variety of photoresists, are performed successfully and analysed so as to enable the reader to relate their known lithography process(es) to the findings. Using the converted tool, 1 cm(2) of nanopattern may be exposed in 6 s, over 3300 times faster than the electron beam equivalent. Nanoimprint tools are commercially available, but these can cost around 1000 times more than this customised computer numerical control (CNC) machine. The converted equipment facilitates rapid production and large area micro- and nanoscale research on small grants, ultimately enabling faster and more diverse growth in this field of science. In comparison to commercial tools, this converted CNC also boasts capacity to handle larger substrates, temperature control and active force control, up to ten times more curing dose and compactness. Actual devices are fabricated using the machine including an expanded nanotopographic array and microfluidic PDMS Y-channel mixers. PMID:26956598

  8. Investigation on Effect of Material Hardness in High Speed CNC End Milling Process.

    PubMed

    Dhandapani, N V; Thangarasu, V S; Sureshkannan, G

    2015-01-01

    This research paper analyzes the effects of material properties on surface roughness, material removal rate, and tool wear on high speed CNC end milling process with various ferrous and nonferrous materials. The challenge of material specific decision on the process parameters of spindle speed, feed rate, depth of cut, coolant flow rate, cutting tool material, and type of coating for the cutting tool for required quality and quantity of production is addressed. Generally, decision made by the operator on floor is based on suggested values of the tool manufacturer or by trial and error method. This paper describes effect of various parameters on the surface roughness characteristics of the precision machining part. The prediction method suggested is based on various experimental analysis of parameters in different compositions of input conditions which would benefit the industry on standardization of high speed CNC end milling processes. The results show a basis for selection of parameters to get better results of surface roughness values as predicted by the case study results. PMID:26881267

  9. Fast manufacturing of E-ELT mirror segments using CNC polishing

    NASA Astrophysics Data System (ADS)

    Gray, C.; Baker, I.; Davies, G.; Evans, R.; Field, N.; Fox-Leonard, T.; Messelink, W.; Mitchell, J.; Rees, P.; Waine, S.; Walker, D. D.; Yu, G.

    2013-09-01

    We report on the first-ever demonstration of grinding and polishing full-size, off-axis aspheric, mirror segments as prototypes for an extremely large telescope, processed entirely in the final hexagonal shape. We first describe the overall strategy for controlling form and mid spatial frequencies, at levels in the vicinity of <10nm RMS surface. This relies first on direct CNC grinding of the base-form of these 1.4m segments, using the Cranfield BoX™ machine. The segments are then mounted on a custom designed (Optic Glyndwr Optoelectronic Engineering Group) three segment hydraulic support, and CNC polished on a Zeeko IRP 1600 machine using a variety of custom tooling. We overview the fullaperture and sub-aperture metrology techniques used to close the process-loop and certify quality, all of which operate with the segment in-situ on the IRP1600. We then focus on the pristine edge-definition achieved by the combination of tool-lift and smoothing operations; results never previously demonstrated on full-size pre-cut hexagonal segments. Finally, the paper discusses the feasibility of scaling the process to deliver 931 segments in seven years, as required for the E-ELT project.

  10. Placement of the material temperature sensor during measuring the accuracy of CNC machine tools

    NASA Astrophysics Data System (ADS)

    Zhao, Dong-sheng; Jia, Min-qiang; Zhang, Jian; Sun, Lei; Li, Wei-jun

    2013-10-01

    In view of the dispute on the placement of material sensor when measuring the positional accuracy of a linear axis of a CNC machine tool, this paper presents the method and principle of deciding where to put the material temperature sensor. The positional accuracy of the linear axis of the machine tool is one of the most important performance parameters, and it must be measured when setup and check. The placement of the material temperature sensor has great influence on the measurement accuracy. At present, there are two main views on this issue: one is to place the sensor on the table of the machine tool, the other is to place it on the feedback system. This conflict between these two debates often makes the measurers feel confused and as a result influences the measure quality, sometimes. This thesis attempts to classify the CNC machine tools positional accuracy measurement according to its different purposes, then further presents the best placement. The thesis also elaborates other relevant questions of the placement of the material temperature sensor.

  11. CNC machine tool's wear diagnostic and prognostic by using dynamic Bayesian networks

    NASA Astrophysics Data System (ADS)

    Tobon-Mejia, D. A.; Medjaher, K.; Zerhouni, N.

    2012-04-01

    The failure of critical components in industrial systems may have negative consequences on the availability, the productivity, the security and the environment. To avoid such situations, the health condition of the physical system, and particularly of its critical components, can be constantly assessed by using the monitoring data to perform on-line system diagnostics and prognostics. The present paper is a contribution on the assessment of the health condition of a computer numerical control (CNC) tool machine and the estimation of its remaining useful life (RUL). The proposed method relies on two main phases: an off-line phase and an on-line phase. During the first phase, the raw data provided by the sensors are processed to extract reliable features. These latter are used as inputs of learning algorithms in order to generate the models that represent the wear's behavior of the cutting tool. Then, in the second phase, which is an assessment one, the constructed models are exploited to identify the tool's current health state, predict its RUL and the associated confidence bounds. The proposed method is applied on a benchmark of condition monitoring data gathered during several cuts of a CNC tool. Simulation results are obtained and discussed at the end of the paper.

  12. cncRNAs: Bi-functional RNAs with protein coding and non-coding functions

    PubMed Central

    Kumari, Pooja; Sampath, Karuna

    2015-01-01

    For many decades, the major function of mRNA was thought to be to provide protein-coding information embedded in the genome. The advent of high-throughput sequencing has led to the discovery of pervasive transcription of eukaryotic genomes and opened the world of RNA-mediated gene regulation. Many regulatory RNAs have been found to be incapable of protein coding and are hence termed as non-coding RNAs (ncRNAs). However, studies in recent years have shown that several previously annotated non-coding RNAs have the potential to encode proteins, and conversely, some coding RNAs have regulatory functions independent of the protein they encode. Such bi-functional RNAs, with both protein coding and non-coding functions, which we term as ‘cncRNAs’, have emerged as new players in cellular systems. Here, we describe the functions of some cncRNAs identified from bacteria to humans. Because the functions of many RNAs across genomes remains unclear, we propose that RNAs be classified as coding, non-coding or both only after careful analysis of their functions. PMID:26498036

  13. Overview of Sustainability Studies of CNC Machining and LAM of Stainless Steel

    NASA Astrophysics Data System (ADS)

    Nyamekye, Patricia; Leino, Maija; Piili, Heidi; Salminen, Antti

    Laser additive manufacturing (LAM), known also as 3D printing, is a powder bed fusion (PBF) type of additive manufacturing (AM) technology used to fabricate metal parts out of metal powder. The development of the technology from building prototype parts to functional parts has increased remarkably in 2000s. LAM of metals is promising technology that offers new opportunities to manufacturing and to resource efficiency. However, there is only few published articles about its sustainability. Aim in this study was to create supply chain model of LAM and CNC machining and create a methodology to carry out a life cycle inventory (LCI) data collection for these techniques. The methodology of the study was literature review and scenario modeling. The acquisition of raw material, production phase and transportations were used as basis of comparison. The modelled scenarios were fictitious and created for industries, like aviation and healthcare that often require swift delivery as well as customized parts. The results of this study showed that the use of LAM offers a possibility to reduce downtime in supply chains of spare parts and reduce part inventory more effectively than CNC machining. Also the gap between customers and business is possible to be shortened with LAM thus offering a possibility to reduce emissions due to less transportation. The results also indicated weight reduction possibility with LAM due to optimized part geometry which allow lesser amount of metallic powder to be used in making parts.

  14. Non-contact automatic measurement of free-form surface profiles on CNC machines

    NASA Astrophysics Data System (ADS)

    Fan, Kuang-Chao; Wen, Kuang-Pu

    1993-09-01

    This paper describes the work to develop a non-contact type automatic measurement system for any free-form surfaces on a CNC machine tool or a coordinate measuring machine (CMM) and its CAD/CAM integration. A laser probe made by Keyence Co. model LC-2220 was integrated into the CNC machine as the non-contact sensor. A measurement software has been developed for automatic surface tracing of any free-form profile. Data transfer to any commercially available CAD/CAM system for reverse engineering is also available via proper DXF file. Extensive calibration work has been carried out on the systematic accuracy of the laser probe with respect to the color material surface slope and edge detection of the workpiece by the use of a HP5528 laser interferometer system. Having employed the surface painting technique the shape error of the copied object relative to its master piece was found within 30 micrometers which is deemed adequate enough to the mold industry.

  15. AT Cnc: A SECOND DWARF NOVA WITH A CLASSICAL NOVA SHELL

    SciTech Connect

    Shara, Michael M.; Mizusawa, Trisha; Zurek, David; Wehinger, Peter; Martin, Christopher D.; Neill, James D.; Forster, Karl; Seibert, Mark

    2012-10-20

    We are systematically surveying all known and suspected Z Cam-type dwarf novae for classical nova shells. This survey is motivated by the discovery of the largest known classical nova shell, which surrounds the archetypal dwarf nova Z Camelopardalis. The Z Cam shell demonstrates that at least some dwarf novae must have undergone classical nova eruptions in the past, and that at least some classical novae become dwarf novae long after their nova thermonuclear outbursts, in accord with the hibernation scenario of cataclysmic binaries. Here we report the detection of a fragmented 'shell', 3 arcmin in diameter, surrounding the dwarf nova AT Cancri. This second discovery demonstrates that nova shells surrounding Z Cam-type dwarf novae cannot be very rare. The shell geometry is suggestive of bipolar, conical ejection seen nearly pole-on. A spectrum of the brightest AT Cnc shell knot is similar to that of the ejecta of the classical nova GK Per, and of Z Cam, dominated by [N II] emission. Galaxy Evolution Explorer FUV imagery reveals a similar-sized, FUV-emitting shell. We determine a distance of 460 pc to AT Cnc, and an upper limit to its ejecta mass of {approx}5 Multiplication-Sign 10{sup -5} M {sub Sun }, typical of classical novae.

  16. Extremely active long-period RS CVn binary HD 12545

    NASA Technical Reports Server (NTRS)

    Bopp, Bernard W.; Fekel, Francis C.; Aufdenberg, Jason P.; Dempsey, Robert; Dadonas, Virgilijus

    1993-01-01

    The active-chromosphere giant HD 12545 is noteworthy for its remarkable 1990 photmetric amplitude of 0.6 mag in V, which implies that nearly half the visible hemisphere of the star was covered by cool spots. We report the results of a spectroscopic study of HD 12545, showing it to be an active-chromosphere binary with an orbital period of 23.97 days. We establish the spectral type as KO III, and measure v sin i = 17 +/- 2 km/s. The various indicators of activity in the optical and ultraviolet suggest that HD 12545 is one of the most active RS CVn systems yet observed. H alpha is a broad, variable emission feature, with a strength comparable to what is observed in very active RS CVn systems such as V711 Tau (HR 1099) or II Peg. The surface fluxes of chromospheric and transition-regions lines in the UV range from 10 to nearly 400 times the solar values. With a moderately strong Li I lambda 6707 feature and a large space motion, HD 12545 is an unusual but not unique giant, since these properties are similar to those of the single active-chromosphere giant HD 33798.

  17. Genetic Variation of BCL2 (rs2279115), NEIL2 (rs804270), LTA (rs909253), PSCA (rs2294008) and PLCE1 (rs3765524, rs10509670) Genes and Their Correlation to Gastric Cancer Risk Based on Universal Tagged Arrays and Fe3O4 Magnetic Nanoparticles.

    PubMed

    Mou, Xianbo; Li, Taotao; Wang, Jiuhai; Ali, Zeeshan; Zhang, Yuanying; Chen, Zhu; Deng, Yan; Li, Song; Su, Enben; Jia, Qiongying; He, Nongyue; Ni, Jian; Cui, Daxiang

    2015-11-01

    With the help of Fe3O4 nagnetic nanoparticles as a solid carrier and an excellent tool for separation, six SNP loci (rs2279115 of BCL2 gene, rs804270 of NEIL2 gene, rs909253 of LTA gene, rs2294008 of PSCA gene, rs3765524 and rs10509670 of PLCE1 gene) were selected to evaluate their relation to gastric cancer risk. Using two kinds of functionalized magnetic nanoparticles and universal tagged arrays, the whole operation procedure including genome DNA extraction and SNP genotyping was performed. All genotypes and allele frequencies were calculated in the cases and controls respectively to analyze their association with gastric cancer risk. Totally 200 pathological samples and 134 normal control subjects were collected. The results demonstrated that four SNP loci (rs2279115, rs804270, rs909253 and rs3765524) showed a potential association with gastric cancer risk, and the other two (rs2294008, rs10509670) possessed no difference/association among cases and controls. PMID:26554163

  18. Radio evidence for nonthermal particle acceleration on stars of late spectral type

    NASA Technical Reports Server (NTRS)

    Lang, Kenneth R.

    1994-01-01

    Radio evidence for nonthermal particle acceleration on stars of late spectral type (G, K, and M) is reviewed, including the pre-main-sequence T Tauri stars, the dwarf M flare stars, and the RS CVn binary stars. Both the long-lasting radio emission and the transient radio flares can be attributed to nonthermal electrons accelerated in magnetically confined coronae, radiating by either incoherent gyrosynchrotron radiation or by coherent processes. Related observations of the Sun provide the framework for interpreting the radio emission of late-type stars. We review recent Very Long Base Interferometry (VLBI) observations of single and binary stars, observations of rapid acceleration and dynamic spectra of dwarf M flare stars, and models for long-lasting radio emission from dwarf M flare stars and RS CVn stars. The VLBI data provide evidence for nonthermal particle acceleration in large-scale magnetospheres several times larger than the stellar radius for T Tauri and RS CVn stars. In contrast, rapid radio flares on dwarf M stars require sources much smaller than the visible star in size, and this is consistent with the VLBI data. Dynamic spectra suggest particle acceleration by relativistic electron beams on dwarf M stars. The long-lived radio radiation of dwarf M stars and RS CVn stars requires more-or-less continuous particle acceleration over periods of hours, perhaps by persistent low-amplitude flaring.

  19. Preparation of the CNC/Ag/beeswax composites for enhancing antibacterial and water resistance properties of paper.

    PubMed

    Liu, Kai; Liang, Hunan; Nasrallah, Joseph; Chen, Lihui; Huang, Liulian; Ni, Yonghao

    2016-05-20

    An effective method of preparing composites containing inorganic (Ag) and organic (beeswax) particles was established in this study. Ag nanoparticles were first immobilized on the cellulose nanocrystals (CNC) during the reduction of AgNO3 in the presence of CNC, then mixed with beeswax by high speed stirring. Scanning transmission electron microscopy (STEM) images indicated that Ag and beeswax particles were uniformly dispersed and stable in the network structure formed by CNC. Upon coating on a paper surface, a layer of beeswax film was evident based on scanning electron microscopy (SEM) images. The dynamic contact angle and antibacterial activity tests indicated that the contact angle of coated paper reached 113.06° and the growth inhibition of Escherichia coli increased to 99.96%, respectively, at a coating amount of 21.53g/m(2). When applied onto paper surface by coating, the CNC/Ag/beeswax composites can impact paper with antibacterial property and improved water resistance. PMID:26917389

  20. Comprehensive reliability allocation method for CNC lathes based on cubic transformed functions of failure mode and effects analysis

    NASA Astrophysics Data System (ADS)

    Yang, Zhou; Zhu, Yunpeng; Ren, Hongrui; Zhang, Yimin

    2015-03-01

    Reliability allocation of computerized numerical controlled(CNC) lathes is very important in industry. Traditional allocation methods only focus on high-failure rate components rather than moderate failure rate components, which is not applicable in some conditions. Aiming at solving the problem of CNC lathes reliability allocating, a comprehensive reliability allocation method based on cubic transformed functions of failure modes and effects analysis(FMEA) is presented. Firstly, conventional reliability allocation methods are introduced. Then the limitations of direct combination of comprehensive allocation method with the exponential transformed FMEA method are investigated. Subsequently, a cubic transformed function is established in order to overcome these limitations. Properties of the new transformed functions are discussed by considering the failure severity and the failure occurrence. Designers can choose appropriate transform amplitudes according to their requirements. Finally, a CNC lathe and a spindle system are used as an example to verify the new allocation method. Seven criteria are considered to compare the results of the new method with traditional methods. The allocation results indicate that the new method is more flexible than traditional methods. By employing the new cubic transformed function, the method covers a wider range of problems in CNC reliability allocation without losing the advantages of traditional methods.

  1. On-line measurement and error compensation of pillar blade-shaped curves in CNC belt grinding

    NASA Astrophysics Data System (ADS)

    Liu, Xin-Xiong; Liu, Xiao-Lian; Chen, Er-Chang; Yang, Qing-Hao

    1993-09-01

    This paper introduces the principle and method of measuring pillar blade curve in CNC belt grinding. And the compensation of manufacture errors of blade use measured results are described in this paper the manufacture precision of the blade may be improved by the introduced method.

  2. Advanced CNC and CAM Series. Educational Resources for the Machine Tool Industry. Course Syllabi, Instructor's Handbook [and] Student Laboratory Manual.

    ERIC Educational Resources Information Center

    Texas State Technical Coll. System, Waco.

    This package consists of course syllabi, an instructor's handbook, and student laboratory manual for a 1-year vocational training program to prepare students for entry-level positions as advanced computer numerical control (CNC) and computer-assisted manufacturing (CAM) technicians.. The program was developed through a modification of the DACUM…

  3. V474 Car: A RARE HALO RS CVn BINARY IN RETROGRADE GALACTIC ORBIT

    SciTech Connect

    Bubar, Eric J.; Mamajek, Eric E.; Jensen, Eric L. N.; Walter, Frederick M.

    2011-04-15

    We report the discovery that the star V474 Car is an extremely active, high velocity halo RS CVn system. The star was originally identified as a possible pre-main-sequence star in Carina, given its enhanced stellar activity, rapid rotation (10.3 days), enhanced Li, and absolute magnitude which places it above the main sequence (MS). However, its extreme radial velocity (264 km s{sup -1}) suggested that this system was unlike any previously known pre-MS system. Our detailed spectroscopic analysis of echelle spectra taken with the CTIO 4 m finds that V474 Car is both a spectroscopic binary with an orbital period similar to the photometric rotation period and metal-poor ([Fe/H] {approx_equal}-0.99). The star's Galactic orbit is extremely eccentric (e {approx_equal} 0.93) with a perigalacticon of only {approx}0.3 kpc of the Galactic center-and the eccentricity and smallness of its perigalacticon are surpassed by only {approx}0.05% of local F/G-type field stars. The observed characteristics are consistent with V474 Car being a high-velocity, metal-poor, tidally locked, chromospherically active binary, i.e., a halo RS CVn binary, and one of only a few such specimens known.

  4. Association of the MTHFR rs1801131 and rs1801133 variants in sporadic Parkinson's disease patients.

    PubMed

    Yuan, Lamei; Song, Zhi; Deng, Xiong; Xiong, Wei; Yang, Zhijian; Deng, Hao

    2016-03-11

    Parkinson's disease (PD) is a common age-dependent neurodegenerative movement disorder related to multiple factors, and genetic factors play an important role in the pathogenesis of PD. Variants in the methylenetetrahydrofolate reductase gene (MTHFR), a gene encoding a folate-dependent enzyme that is involved in homocysteine metabolism, have been reported to be associated with PD. To explore the role of the MTHFR gene in the development of PD in Chinese Han population, we analyzed two MTHFR variants (rs1801131 and rs1801133) in a patient cohort consisting of 512 patients with PD from mainland China and a control cohort consisting of 512 age, gender and ethnicity matched normal subjects. Statistically significant differences in genotypic and allelic frequencies were detected in the MTHFR variant rs1801133 (P=0.022 and 0.007, respectively; odds ratio=0.780, 95% confidence interval=0.651-0.934). In addition, the A-T haplotype of rs1801131-rs1801133 showed a protective role against PD development (P=0.007, odds ratio=0.779, 95% confidence interval=0.650-0.933). Our results suggested that the T allele of rs1801133 variant and A-T haplotype of rs1801131-rs1801133 in the MTHFR gene may decrease the risk of developing PD in Chinese Han population from mainland China. PMID:26806866

  5. The Asymmetric Outflow of RS Ophiuchi

    NASA Astrophysics Data System (ADS)

    Mohamed, S.; Booth, R.; Podsiadlowski, Ph.

    2013-01-01

    RS Ophiuchi (RS Oph) is a symbiotic binary consisting of a hot white dwarf accreting from the slow, dense stellar wind of a cool, red giant companion. The system belongs to, and is one of the best studied examples of, an even smaller subclass of binaries known as recurrent novae in which the white dwarf undergoes repeated thermonuclear outbursts. We present 3D smoothed particle hydrodynamics (SPH) models of mass transfer from the red giant to the white dwarf, followed by a nova outburst. We show that the outflow in the former is strongly concentrated towards the binary orbital plane. The nova ejecta is thus constrained in the equatorial directions, resulting in a bipolar outflow. The white dwarf in RS Oph is thought to be close to the Chandrasekhar mass, making the system a likely Type Ia supernova candidate. We discuss the role that such a highly structured circumstellar medium will play in the evolution of the supernova remnant.

  6. Study on grinding of free-form optics surface in three-axis CNC machine

    NASA Astrophysics Data System (ADS)

    Yang, Haicheng; Zhang, Yun-long; Zhang, Feng; Wang, Zhibin; Bao, Long-xiang; Su, Ying; Guo, Rui; Liu, Xuan-min

    2014-08-01

    Due to the glass is a type of brittle material, so the high-precision free-form optics of glass material is usually machined by the technical of grinding. In this paper, for the characteristics of the diamond grinding wheel, analyzing the grinding path of free-form optics and mathematical model of the path is established based on the three-axis CNC grinding device. Moreover, the cause of the interference in the process of grinding is analyzed and the methods of avoiding. Finally, based on the above analysis results, through the experiment, the free-form optics surface accuracy was reached to 3.6um, realize the machining of the free-form optics.

  7. Concurrent Collections (CnC): A new approach to parallel programming

    SciTech Connect

    2010-05-07

    A common approach in designing parallel languages is to provide some high level handles to manipulate the use of the parallel platform. This exposes some aspects of the target platform, for example, shared vs. distributed memory. It may expose some but not all types of parallelism, for example, data parallelism but not task parallelism. This approach must find a balance between the desire to provide a simple view for the domain expert and provide sufficient power for tuning. This is hard for any given architecture and harder if the language is to apply to a range of architectures. Either simplicity or power is lost. Instead of viewing the language design problem as one of providing the programmer with high level handles, we view the problem as one of designing an interface. On one side of this interface is the programmer (domain expert) who knows the application but needs no knowledge of any aspects of the platform. On the other side of the interface is the performance expert (programmer or program) who demands maximal flexibility for optimizing the mapping to a wide range of target platforms (parallel / serial, shared / distributed, homogeneous / heterogeneous, etc.) but needs no knowledge of the domain. Concurrent Collections (CnC) is based on this separation of concerns. The talk will present CnC and its benefits. About the speaker Kathleen Knobe has focused throughout her career on parallelism especially compiler technology, runtime system design and language design. She worked at Compass (aka Massachusetts Computer Associates) from 1980 to 1991 designing compilers for a wide range of parallel platforms for Thinking Machines, MasPar, Alliant, Numerix, and several government projects. In 1991 she decided to finish her education. After graduating from MIT in 1997, she joined Digital Equipment’s Cambridge Research Lab (CRL). She stayed through the DEC/Compaq/HP mergers and when CRL was acquired and absorbed by Intel. She currently works in the Software and Services Group / Technology Pathfinding and Innovation.

  8. Concurrent Collections (CnC): A new approach to parallel programming

    ScienceCinema

    None

    2011-10-06

    A common approach in designing parallel languages is to provide some high level handles to manipulate the use of the parallel platform. This exposes some aspects of the target platform, for example, shared vs. distributed memory. It may expose some but not all types of parallelism, for example, data parallelism but not task parallelism. This approach must find a balance between the desire to provide a simple view for the domain expert and provide sufficient power for tuning. This is hard for any given architecture and harder if the language is to apply to a range of architectures. Either simplicity or power is lost. Instead of viewing the language design problem as one of providing the programmer with high level handles, we view the problem as one of designing an interface. On one side of this interface is the programmer (domain expert) who knows the application but needs no knowledge of any aspects of the platform. On the other side of the interface is the performance expert (programmer or program) who demands maximal flexibility for optimizing the mapping to a wide range of target platforms (parallel / serial, shared / distributed, homogeneous / heterogeneous, etc.) but needs no knowledge of the domain. Concurrent Collections (CnC) is based on this separation of concerns. The talk will present CnC and its benefits. About the speaker Kathleen Knobe has focused throughout her career on parallelism especially compiler technology, runtime system design and language design. She worked at Compass (aka Massachusetts Computer Associates) from 1980 to 1991 designing compilers for a wide range of parallel platforms for Thinking Machines, MasPar, Alliant, Numerix, and several government projects. In 1991 she decided to finish her education. After graduating from MIT in 1997, she joined Digital Equipment?s Cambridge Research Lab (CRL). She stayed through the DEC/Compaq/HP mergers and when CRL was acquired and absorbed by Intel. She currently works in the Software and Services Group / Technology Pathfinding and Innovation.

  9. Optical and X-ray studies of chromospherically active stars: FR Cancri, HD 95559 and LO Pegasi

    NASA Technical Reports Server (NTRS)

    Pandey, J. C.; Singh, K. P.; Drake, S. A.; Sagar, R.

    2005-01-01

    We present a multiwavelength study of three chromospherically active stars, namely FR Cnc (= BD +16 degrees 1753), HD 95559 and LO Peg (=BD +22 degrees 4409), including newly obtained optical photometry, (for FR Cnc) low-resolution optical spectroscopy, as well as archival IR and X-ray observations. The BVR photometry carried out during the years 2001 - 2004 has found significant photometric variability to be present in all three stars. For FR Cnc, a photometric period 0.826685 +/- 0.000034 d has been established. The strong variation in the phase and amplitude of the FR Cnc light curves when folded on this period implies the presence of evolving and migrating spots or spot groups on its surface. Two independent spots with migration periods of 0.97 and 0.93 years respectively are inferred. The photometry of HD 95559 suggests the formation of a spot (group) during the interval of our observations. We infer the existence of two independent spots or groups in the photosphere of LO Peg, one of which has a migration period of 1.12 years. The optical spectroscopy of FR Cnc carried out during 2002-2003, reveals the presence of strong and variable Ca I1 H and K, H(sub beta) and H(sub alpha) emission features indicative of high level of chromospheric activity. The value of 5.3 for the ratio of the excess emission in H(sub alpha) to H(sub beta), EH(sub alpha)/EH(sub beta), suggests that the chromospheric emission may arise from an extended off-limb region. We have searched for the presence of color excesses in the near-IR JHK bands of these stars using 2MASS data, but none of them appear to have any significant color excess. We have also analyzed archival X-ray observations of HD 95559 and LO Peg carried out by with the ROSAT observatory. The best fit models to their X-ray spectra imply the presence of two coronal plasma components of differing temperatures and with sub-solar metal abundances. The inferred emission measures and temperatures of these systems are similar to those found for other active dwarf stars. The kinematics of FR Cnc suggest that it is a very young (35 - 55 Myrs) main-sequence star and a possible member of the IC 2391 supercluster. LO Peg also has young disk-type kinematics and has been previously suggested to be a member of the 100 Mys old Local Association (Pleiades Moving Group). The kinematics of HD 95559 indicate it is a possible member of the 600 Myrs old Hyades supercluster.

  10. Optical and X-Ray Studies of Chromospherically Active Stars: FR Cancri, HD 95559, and LO Pegasi

    NASA Astrophysics Data System (ADS)

    Pandey, J. C.; Singh, K. P.; Drake, S. A.; Sagar, R.

    2005-09-01

    We present a multiwavelength study of three chromospherically active stars, namely, FR Cnc (BD +16°1753), HD 95559, and LO Peg (BD +22°4409), including newly obtained optical photometry and low-resolution optical spectroscopy for FR Cnc, as well as archival IR and X-ray observations. The BVR photometry carried out from 2001 to 2004 has found significant photometric variability to be present in all three stars. For FR Cnc, a photometric period of 0.8267+/-0.0004 days has been established. The strong variation in the phase and amplitude of the FR Cnc light curves when folded on this period implies the presence of evolving and migrating spots or spot groups on its surface. Two independent spots with migration periods of 0.97 and 0.93 yr, respectively, are inferred. The photometry of HD 95559 suggests the formation of a spot (group) during the interval of our observations. We infer the existence of two independent spots or groups in the photosphere of LO Peg, one of which has a migration period of 1.12 yr. The optical spectroscopy of FR Cnc carried out during 2002-2003 reveals the presence of strong and variable Ca II H and K, Hβ, and Hα emission features indicative of a high level of chromospheric activity. The value of 5.3 for the ratio of the excess emission in Hα to Hβ, EHα/EHβ, suggests that the chromospheric emission may arise from an extended off-limb region. We have searched for the presence of color excesses in the near-IR JHK bands of these stars using Two Micron All Sky Survey data, but none of them appear to have any significant color excess. We have also analyzed archival X-ray observations of HD 95559 and LO Peg carried out with the ROSAT observatory. The best-fit models to their X-ray spectra imply the presence of two coronal plasma components of differing temperatures and with subsolar metal abundances. The inferred emission measures and temperatures of these systems are similar to those found for other active dwarf stars. The kinematics of FR Cnc suggest that it is a very young (35-55 Myr) main-sequence star and a possible member of the IC 2391 supercluster. LO Peg also has young disk-type kinematics and has been previously suggested to be a member of the 100 Myr old Local Association (Pleiades moving group). The kinematics of HD 95559 indicate it is a possible member of the 600 Myr old Hyades supercluster.

  11. A SUPER-EARTH TRANSITING A NAKED-EYE STAR

    SciTech Connect

    Winn, Joshua N.; Matthews, Jaymie M.; Kallinger, Thomas; Dragomir, Diana; Dawson, Rebekah I.; Holman, Matthew J.; Sasselov, Dimitar; Fabrycky, Daniel; Guenther, David B.; Moffat, Anthony F. J.; Rowe, Jason F.; Rucinski, Slavek

    2011-08-10

    We have detected transits of the innermost planet 'e' orbiting 55 Cnc (V = 6.0), based on two weeks of nearly continuous photometric monitoring with the MOST space telescope. The transits occur with the period (0.74 days) and phase that had been predicted by Dawson and Fabrycky, and with the expected duration and depth for the crossing of a Sun-like star by a hot super-Earth. Assuming the star's mass and radius to be 0.963{sup +0.051}{sub -0.029} M{sub sun} and 0.943 {+-} 0.010 R{sub sun}, the planet's mass, radius, and mean density are 8.63 {+-} 0.35 M{sub +}, 2.00 {+-} 0.14 R{sub +}, and 5.9{sup +1.5}{sub -1.1} g cm{sup -3}, respectively. The mean density is comparable to that of Earth, despite the greater mass and consequently greater compression of the interior of 55 Cnc e. This suggests a rock-iron composition supplemented by a significant mass of water, gas, or other light elements. Outside of transits, we detected a sinusoidal signal resembling the expected signal due to the changing illuminated phase of the planet, but with a full range (168 {+-} 70 ppm) too large to be reflected light or thermal emission. This signal has no straightforward interpretation and should be checked with further observations. The host star of 55 Cnc e is brighter than that of any other known transiting planet, which will facilitate future investigations.

  12. Spots on T Tauri stars

    NASA Astrophysics Data System (ADS)

    Bouvier, J.; Bertout, C.

    1989-02-01

    Periodic light curves were recorded for the following 15 T Tauri stars (for nine of which this was the first detection of periodic variability): V 410 Tau, DF Tau, UX Tau A, FK 1, FK 2, WK 2, DN Tau, GW Ori, SY Cha, LH(alpha) 332-20, LH(alpha) 332-21, CoD-33-deg 10685, RY Lup, SR 12, and SR 9. The previously reported periodic variability of the SY Cha and RY Lup stars was confirmed. These periodic variations are thought to result from rotational modulation by a group of spots at the stellar surface. The properties of spots on 11 stars were deduced from extensive light-curve synthesis. In most cases, they were found to be comparable to the properties of spots found on RS CVn stars.

  13. Association between polymorphism of the norepinephrine transporter gene rs2242446 and rs5669 loci and depression disorders

    PubMed Central

    Pan, Yu; Cheng, Qi; Shan, Mo-Shui; Yan, Jin

    2015-01-01

    Objective: To explore the association between polymorphism of the norepinephrine transporter (NET) gene rs2242446 and rs5669 loci and depression in Chinese Han population. Methods: A case-control study was carried out, the gene types and allele distributions of NFT gene rs2242446 and rs5569 loci in 302 depression patients and 302 healthy controls were detected by Taqman SNP genotyping technology. Results: The gene types and allele frequency distributions of NFT gene rs2242446 and rs5569 loci had significant differences between case group and control group (rs2242446, x2=26.045, P<0.05, x2=8.827, P<0.05, rs5569, x2=42.47, P<0.05, x2=20.9, P<0.05). The CC genotype of NET gene rs2242446 locus and rs5569 loci was a protective factor of depression compared with the CT and TT genotypes. Conclusion: The NET genepoly morphism of rs2242446 and rs5569 loci was a ssociated with depression in Chinese Han population, in which the CC genotype of rs2242446 and rs5569 loci was a protective factor of depression. PMID:26770504

  14. Association between ANKK1 (rs1800497) and LTA (rs909253) Genetic Variants and Risk of Schizophrenia

    PubMed Central

    Arab, Arwa H.; Elhawary, Nasser A.

    2015-01-01

    Limited research has assessed associations between schizophrenia and genetic variants of the ankyrin repeat and kinase domain containing 1 (ANKK1) and lymphotoxin-alpha (LTA) genes among individuals of Middle Eastern ancestry. Here we present the first association study investigating the ANKK1 rs1800497 (T>C) and LTA rs909253 (A>G) single-nucleotide polymorphisms in an Egyptian population. Among 120 patients with DSM-IV and PANSS (Positive and Negative Syndrome Scale) assessments of schizophrenia and 100 healthy controls, we determined the genotypes for the polymorphisms using endonuclease digestion of amplified genomic DNA. Results confirmed previous findings from different ethnic populations, in that the rs1800497 and rs909253 polymorphisms were both associated with risk of schizophrenia. Differences between the genotypes of cases and controls were strongly significant (P = 0.0005 for rs1800497 and P = 0.001 for rs909253). The relative risk to schizophrenia was 1.2 (P = 0.01) for the C allele and 0.8 (P = 0.04) for the G allele. The CC, GG, and combined CC/AA genotypes were all more frequent in cases than in controls. These results support an association between ANKK1 and LTA genetic markers and vulnerability to schizophrenia and show the potential influence of just one copy of the mutant C or G allele in the Egyptian population. PMID:26114114

  15. PTK2 rs7460 and rs7843014 Polymorphisms and Exceptional Longevity: A Functional Replication Study

    PubMed Central

    Fuku, Noriyuki; He, Zi-hong; Tian, Ye; Arai, Yasumichi; Abe, Yukiko; Murakami, Haruka; Miyachi, Motohiko; Yvert, Thomas; Venturini, Letizia; Santiago, Catalina; Santos-Lozano, Alejandro; Rodríguez, Gabriel; Ricevuti, Giovanni; Pareja-Galeano, Helios; Sanchis-Gomar, Fabian; Emanuele, Enzo; Hirose, Nobuyoshi; Lucia, Alejandro

    2014-01-01

    Abstract Focal adhesion is critical for cell survival. The focal adhesion kinase (FAK, or PTK2) is an important component of the human interactome and thus is a potential longevity-related protein. Here we studied the association between two PTK2 gene single-nucleotide polymorphisms (SNPs) (rs7843014, rs7460) and exceptional longevity (EL). In addition to gaining insight into their functionality by determining luciferase gene reporter activity, we studied the genotype/allele frequency of these two SNPs among three different cohorts: (1) Spanish centenarians (n=175, 100–111 years, 144 women) and healthy controls (n=355, 20–50 years, 284 women); (2) Italian centenarians (n=79, 100–104 years, 40 women) and controls (n=316, 29–50 years, 156 women); and (3) Japanese centenarians (n=742, 100–116 years, 623 women) and healthy controls (n=499, 23–59 years, 356 women). Both SNPs had functional significance, with the A allele up-regulating luciferase activity compared to the other allele (rs7460 T allele and rs7843014 C allele, respectively). The A allele of both SNPs was negatively associated with EL in the Spanish cohort (rs7460, odds ratio [OR] adjusted by sex=0.40, 95% confidence intervals [CI] 0.3, 0.6, p<0.001); rs7843014, OR=0.37, 95% CI 0.3, 0.5, p<0.001). The OR of being a centenarian if having the rs7460-TT genotype was 6.68 (95% CI 4.1, 10.8, p<0.001). The rs7843014 CC genotype was also positively associated with EL (OR=7.58, 95% CI 4.6, 12.3, p<0.001]. No association was, however, found for the Italian or Japanese cohorts. Thus, two genotypes of the FAK gene, rs7460 TT and rs7843014 CC, are possibly associated with lower gene expression and might favor the likelihood of reaching EL in the Spanish population. Further research is needed to unveil the mechanisms by which FAK expression could perhaps influence the rate of aging. PMID:24930376

  16. Association of Polymorphisms (rs 1799782, rs25489 and rs25487) in XRCC1 and (rs 13181) XPD genes with Acute Coronary Artery Syndrome in Subjects from Multan, Pakistan.

    PubMed

    Hameed, Hafsa; Faryal, Maemona; Aslam, Muhammad Assad; Akbar, Atif; Saad, Abu Bakar Ali; Pasha, Muhammad Burhan; Latif, Muhammad; Rehan Sadiq Shaikh, Rehan Rehan Sadiq Shaikh; Ali, Muhammad; Iqbal, Furhan

    2016-05-01

    Acute coronary artery syndrome (ACS) is the major cause of mortality in Pakistan with genetic and environmental influence on the incidence of the disease. This case-control study was designed to find out if a correlation is existing between ACS and single nucleotide polymorphisms (SNPs) in DNA repair genes XPD [at codon 751, rs 13181 (Lys to Gln)] and XRCC1 [at codon 399, rs25487 (Arg to Gln); 280, rs25489 (Arg to His) and 194, rs 1799782 (Arg to Trp)] either individually or in various combination with each other (haplotype analysis). The objective of this study was to find out the association of various studied risk factors and serum lipid profile of the subjects with the disease, if any. PCR-RFLP method was used to determine genotype at specific codon in 221 subjects (115 ACS patients and 106 healthy controls) from Southern Punjab population. Genotypic and allelic frequency distribution among the cases and controls revealed that all the studied SNPs were not individually associated with the ACS. Haplotype analysis revealed that subjects having wild type combination of all three XRCC1 SNPs had greater susceptibility to ACS than any other studied genotypic combinations. Analysis of risk factors revealed that hypertension (P<0.001), age (P=0.05), education (P<0.001), gender (P<0.001), family history (P=0.005), smoking habit (P=0.002) and diabetes (P<0.001) were significantly associated with the incidence of ACS. Serum lipid profile analysis indicated that cholesterol level was significantly higher (P=0.048) in patients (161.5mg/dL) than controls (142.1mg/dL) while triglyceride remained unaffected (P=0.87) when compared between the two treatments. PMID:27166553

  17. Lack of associations between rs2910164 and rs11614913 polymorphisms and the risk of ischemic stroke

    PubMed Central

    Qin, Biyong; Zheng, Yan; Zhang, Wenjun; Wang, Chengmou; Wang, Jian; Cai, Zhiyou

    2015-01-01

    Emerging evidence suggests that single nucleotide polymorphisms (SNPs) in microRNA genes may play a role in the development of cerebrovascular diseases including ischemic stroke through functionally modulating the expression of microRNA target genes. However, the current studies regarding the associations of the common microRNA polymorphisms with susceptibility to ischemic stroke have obtained discrepant results, which prompted us to perform a meta-analysis for a more precise estimation of the concerned associations. Relevant studies evaluating the associations between two common polymorphisms (miR-146a rs2910164 and miR-196a2 rs11614913) and the risk of ischemic stroke were retrieved from the PubMed, Embase, Cochrane Library, Google Scholar, Chinese Wanfang, Chinese Biomedical Database, and Chinese National Knowledge Infrastructure databases. The odds ratio (OR) with its 95% confidence interval (95% CI) were pooled to assess the strength of the associations using RevMan 5.2 and Stata 12.0 software. A total of 5 case-control studies with 2069 cases and 2061 controls on rs2910164, 4 case-control studies with 1873 cases and 1856 controls on rs11614913 polymorphisms were enrolled in the meta-analysis. Overall, neither allele frequency nor genotype distribution of the two common polymorphisms was found to be associated with risk for ischemic stroke in all genetic models. The subgroup analysis revealed a significant association between miR-146a rs2910164 polymorphism and increased risk of ischemic stroke in large sample size group and in Koreans under homozygous, allele, dominant and recessive models. The present meta-analysis suggests that the two common polymorphisms (rs2910164, rs11614913) may not contribute to the susceptibility to ischemic stroke. However, more well-designed studies with large sample size are warranted to further validate the results in different ethnicities. PMID:26770439

  18. Stars and Star Myths.

    ERIC Educational Resources Information Center

    Eason, Oliver

    Myths and tales from around the world about constellations and facts about stars in the constellations are presented. Most of the stories are from Greek and Roman mythology; however, a few Chinese, Japanese, Polynesian, Arabian, Jewish, and American Indian tales are also included. Following an introduction, myths are presented for the following 32…

  19. Stars and Star Myths.

    ERIC Educational Resources Information Center

    Eason, Oliver

    Myths and tales from around the world about constellations and facts about stars in the constellations are presented. Most of the stories are from Greek and Roman mythology; however, a few Chinese, Japanese, Polynesian, Arabian, Jewish, and American Indian tales are also included. Following an introduction, myths are presented for the following 32

  20. Be Stars

    NASA Astrophysics Data System (ADS)

    Peters, G.; Murdin, P.

    2000-11-01

    A Be star (pronounced `bee-ee' star) is a non-supergiant B-type star whose spectrum displays or has displayed one or more Balmer lines in emission and Be is the notation for the spectral classification of such a star (see also CLASSIFICATION OF STELLAR SPECTRA). `Classical' Be stars are believed to have acquired the circumstellar (CS) material that produces the Balmer emission through ejection of...

  1. Development of a high precision tabletop versatile CNC wire-EDM for making intricate micro parts

    NASA Astrophysics Data System (ADS)

    Liao, Yunn-Shiuan; Chen, Shun-Tong; Lin, Chang-Sheng

    2005-02-01

    The micro-electrical discharge machining (micro-EDM) process has been proved to be appropriate for making 3D micro parts that are difficult and even impossible to manufacture by other processes. In this paper a high precision tabletop CNC wire electrical discharge machine (wire EDM) designed specifically for machining complex shape micro parts or structures is developed. In the machine developed, a novel micro-wire-cutting mechanism is designed, an approach to control wire tension by magnetic force is proposed and a servo feed control strategy, in accordance with the measured gap voltage, is designed and implemented. To verify the functions and capabilities of the machine developed, several thick micro outer and internal spur gears and rack are machined. It shows that the taper angle along the wall or cavity of a part that appears when other micro-EDM processes are applied can be avoided. A very good dimensional accuracy of 1 m and a surface finish of Rmax equal to 0.64 m are achieved. The satisfactory cutting of a miniature 3D pagoda with a micro-hooked structure also reveals that the machine developed is versatile, and can be used as a new tool for making intricate micro parts.

  2. An improved method for risk evaluation in failure modes and effects analysis of CNC lathe

    NASA Astrophysics Data System (ADS)

    Rachieru, N.; Belu, N.; Anghel, D. C.

    2015-11-01

    Failure mode and effects analysis (FMEA) is one of the most popular reliability analysis tools for identifying, assessing and eliminating potential failure modes in a wide range of industries. In general, failure modes in FMEA are evaluated and ranked through the risk priority number (RPN), which is obtained by the multiplication of crisp values of the risk factors, such as the occurrence (O), severity (S), and detection (D) of each failure mode. However, the crisp RPN method has been criticized to have several deficiencies. In this paper, linguistic variables, expressed in Gaussian, trapezoidal or triangular fuzzy numbers, are used to assess the ratings and weights for the risk factors S, O and D. A new risk assessment system based on the fuzzy set theory and fuzzy rule base theory is to be applied to assess and rank risks associated to failure modes that could appear in the functioning of Turn 55 Lathe CNC. Two case studies have been shown to demonstrate the methodology thus developed. It is illustrated a parallel between the results obtained by the traditional method and fuzzy logic for determining the RPNs. The results show that the proposed approach can reduce duplicated RPN numbers and get a more accurate, reasonable risk assessment. As a result, the stability of product and process can be assured.

  3. A low glitch 12-bit current-steering CMOS DAC for CNC systems

    NASA Astrophysics Data System (ADS)

    Jianming, Lei; Hanshu, Gui; Beiwen, Hu

    2013-02-01

    A 12-bit, 100-MHz CMOS current-steering D/A converter for CNC (computer number control) systems is presented. To reduce the glitch and increase the SFDR (spurious-free dynamic range), a low crosspoint switch driver and a special dummy switch are applied. In addition, a 4-5-3 segmental structure is used to optimize the performance and layout area. After improvement, the biggest glitch energy decreased from 6.7 pVs to 1.7 pVs, the INL decreased from 2 LSB to 0.8 LSB, the SFDR is 78 dB at a 100-MSPS clock rate and 1 MHz output frequency. This DAC can deliver up to 20.8 mA full-scale current into a 50 ? load. The power when operating at full-scale current is 163 mW. The layout area is 1.8 1.8 mm2 in a standard 0.35-?m CMOS technology.

  4. Automated optical fabrication: first results from the new Precessions 1.2m CNC polishing machine

    NASA Astrophysics Data System (ADS)

    Walker, D. D.; Beaucamp, A. T. H.; Doubrovski, V.; Dunn, C.; Evans, R.; Freeman, R.; Kelchner, J.; McCavana, G.; Morton, R.; Riley, D.; Simms, J.; Yu, G.; Wei, X.

    2006-06-01

    The requirements of space and defence optical systems and ground-based astronomy (especially extremely large telescopes) are providing optical fabricators with new challenges. These challenges particularly concern process speed, determinism and automation, and tighter tolerances on surface form and texture. Moreover, there is a growing demand for complex off-axis and 'freeform' surfaces and for larger components of the ~1m scale. With this in view, we first report on form-correction on a smaller analogue of the IRP1200: an IRP400 in service in industry. We then report on the design, commissioning and preliminary process-development results from the first of the scaled-up 1.2m capacity CNC polishing machine from Zeeko, Ltd. This machine delivers the 'Classic' bonnet-based process, together with two new processes: fluid-jet polishing and the hybrid soft-grinding/polishing process called 'Zeeko-Grolish.' We indicate how this trio of processes running on the same machine platform with unified software can provide an unprecedented dynamic range in both volumetric removal rate and removal spot-size. This leads into a discussion of how these processes may be brought to bear on optimal control of texture and form. Preliminary performance of the 1.2m machine is illustrated with results on both axially-symmetric and more complex removal regimes. The paper concludes with an overview of the relevance of the technology to efficient production of instrumentation-optics, space optics and segmented telescope mirrors.

  5. Design and manufacturing of cranioplasty implants by 3-axis cnc milling.

    PubMed

    Hieu, L C; Bohez, E; Vander Sloten, J; Oris, P; Phien, H N; Vatcharaporn, E; Binh, P H

    2002-01-01

    Although various techniques and materials have been used for making cranioplasty implants, personalized cranioplasty implants are high in cost because of expensive materials and production technology, long design and manufacturing time, and intensive labor use. This research was a part of our research project in ASEAN countries to investigate feasible technical solutions of minimizing the implant cost based on available production technologies in the region. The use of 3-axis CNC (Computer Numerical Control) milling techniques for making molds to fabricate PMMA implants was successfully investigated. With the development of a design support program bridging between Computer Aided Design (CAD) and Medical Image Processing (MIP) system, the time for geometrical modeling of implants and molds was reduced to half a day. The machining time to complete a mold was about 5 to 6 hours; and it took maximal 2 hours to fabricate an implant with self-curing PMMA and 3 and half hours for fabricating an implant with heat-curing PMMA. The cost of implants is acceptable for the ASEAN region. PMID:12368561

  6. Cost minimizing of cutting process for CNC thermal and water-jet machines

    NASA Astrophysics Data System (ADS)

    Tavaeva, Anastasia; Kurennov, Dmitry

    2015-11-01

    This paper deals with optimization problem of cutting process for CNC thermal and water-jet machines. The accuracy of objective function parameters calculation for optimization problem is investigated. This paper shows that working tool path speed is not constant value. One depends on some parameters that are described in this paper. The relations of working tool path speed depending on the numbers of NC programs frames, length of straight cut, configuration part are presented. Based on received results the correction coefficients for working tool speed are defined. Additionally the optimization problem may be solved by using mathematical model. Model takes into account the additional restrictions of thermal cutting (choice of piercing and output tool point, precedence condition, thermal deformations). At the second part of paper the non-standard cutting techniques are considered. Ones may lead to minimizing of cutting cost and time compared with standard cutting techniques. This paper considers the effectiveness of non-standard cutting techniques application. At the end of the paper the future research works are indicated.

  7. Evidence of interaction of CARD8 rs2043211 with NALP3 rs35829419 in Crohn's disease.

    PubMed

    Roberts, R L; Topless, R K G; Phipps-Green, A J; Gearry, R B; Barclay, M L; Merriman, T R

    2010-06-01

    The location of CARD8 within an inflammatory bowel disease (IBD) locus and its role in the NALP3 inflammasome and as a nuclear factor (NF)kappaB inhibitor make it an attractive candidate risk gene for IBD. However, studies testing for the association of the CARD8 loss-of-function single-nucleotide polymorphism (SNP) rs2043211 with IBD have yielded mixed results. A recent study provided evidence that this discordance may result from an interaction of rs2043211 with loss-of-function variants in nucleotide-binding oligomerization domain protein 2 (NOD2) and a gain-of-function SNP (rs35829419) in NALP3. To confirm this interaction, we conducted a replication in an independent IBD sample set (n=1009 patients, n=517 controls). We found that the presence of the minor allele of rs2043211 with the major allele of rs35829419 conferred a protective effect against Crohn's disease (and vice versa), which intensified in the absence of NOD2 mutations (P(1,2/1,1)=0.009, odds ratio (OR)=0.66, 95% confidence interval (CI) (0.48-0.90); P(1,1/1,2)=0.015, OR=0.35, 95% CI (0.15-0.82)). We propose that these genotype combinations protect against gut inflammation by preventing the NALP3 inflammasome from producing excessive interleukin-1beta. PMID:20182451

  8. 40 CFR 180.1114 - Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS; exemptions from the requirement of a tolerance... Tolerances § 180.1114 Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas...

  9. 40 CFR 180.1114 - Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS; exemptions from the requirement of a tolerance... Tolerances § 180.1114 Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas...

  10. 40 CFR 180.1114 - Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS; exemptions from the requirement of a tolerance... Tolerances § 180.1114 Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas...

  11. An Analysis of Light Variations of RS Canum Venaticorum Binary Systems.

    NASA Astrophysics Data System (ADS)

    Caton, Daniel Bruce

    Photoelectric data for fourteen RS Canum Venaticorum binary systems were obtained by the author from 1978 through 1981, at Rosemary Hill Observatory. These data are presented in the form of light curves and tabulated magnitudes and heliocentric Julian Dates. The outside-of-eclipse points for eight systems were Fourier analyzed for measurement of any distortion wave in the light curve. The wave in RS Canum Venaticorum itself was found to have moved half a phase unit in only two years. A wave was discovered in the light curve of RZ Eridani, and was found to have changed in a manner consistent with the starspot model for RS CVn systems. The light curve for UX Comae Bernices was found to have a large amount of intrinsic scatter, and the system was found to be anomalously bright on one night. These characteristics suggest that some type of flare activity may be present in that system. The other five systems analyzed were found to have waves consistent with other published results, or to have no definite wave at all. The possibility of detecting spots and deriving spot sizes from secondary eclipse observations was also explored. For this purpose the Wilson-Devinney computer program for light curve synthesis was modified to allow spots on the secondary star. Comparison of computer synthesized secondary eclipses of spotted stars to actual observations showed that there is little chance of detecting fluctuations due to individual spots. It was found that there is even less chance for discriminating between a few large spots and a large number of smaller spots. However, the program did produce good fits to RS CVn light curves, using reasonable spot parameters.

  12. Association of Adiponectin rs1501299 and rs266729 Gene Polymorphisms With Nonalcoholic Fatty Liver Disease

    PubMed Central

    Hashemi, Mohammad; Hanafi Bojd, Hamideh; Eskandari Nasab, Ebrahim; Bahari, Ali; Hashemzehi, Noor Allah; Shafieipour, Sara; Narouie, Behzad; Taheri, Mohsen; Ghavami, Saeid

    2013-01-01

    Background Genetic and environmental factors are important for the development of nonalcoholic fatty liver disease (NAFLD). Adiponectin is a white and brown adipose tissue hormone, and have been found to play essential roles in the regulation of energy homoeostasis. Recent reports have identified a possible role of adiponectin in NAFLD via PPARγ pathway. Objectives The present study was designed to find out the impact of adiponectin rs1501299 (276G/T) and rs266729 (-11377C/G) gene polymorphisms in NAFLD. Patients and Methods Eighty-three patients with diagnosis of NAFLD, and 93 healthy subjects were included in the study. Tetra ARMS-PCR was designed to detect single nucleotide polymorphisms. Results A significant difference was found between NAFLD and control group regarding the rs266729 polymorphism (χ2 = 7.35, P = 0.025). The rs266729 polymorphism increased the risk of NAFLD in codominant (CC vs. CG: OR = 2.18, 95% CI = 1.16 - 4.12, P = 0.016) and dominant (CC vs. CG/GG: OR = 2.31, 95% CI = 1.25 - 4.27; P = 0.008) inheritance tested models. The G allele increased the risk of NAFLD (OR = 1.63, 95% CI = 1.03 - 2.57, P = 0.037) in comparison with C allele. No significant difference was found between the groups concerning adiponectin rs1501299 gene polymorphism (χ2 = 0.70, P = 0.697). Conclusions adiponectin rs266729 polymorphism might be a candidate gene, which determines the susceptibility to NAFLD. Larger studies are necessary to confirm these findings in various populations. PMID:23922565

  13. Mass and Reliability System (MaRS)

    NASA Technical Reports Server (NTRS)

    Barnes, Sarah

    2016-01-01

    The Safety and Mission Assurance (S&MA) Directorate is responsible for mitigating risk, providing system safety, and lowering risk for space programs from ground to space. The S&MA is divided into 4 divisions: The Space Exploration Division (NC), the International Space Station Division (NE), the Safety & Test Operations Division (NS), and the Quality and Flight Equipment Division (NT). The interns, myself and Arun Aruljothi, will be working with the Risk & Reliability Analysis Branch under the NC Division's. The mission of this division is to identify, characterize, diminish, and communicate risk by implementing an efficient and effective assurance model. The team utilizes Reliability and Maintainability (R&M) and Probabilistic Risk Assessment (PRA) to ensure decisions concerning risks are informed, vehicles are safe and reliable, and program/project requirements are realistic and realized. This project pertains to the Orion mission, so it is geared toward a long duration Human Space Flight Program(s). For space missions, payload is a critical concept; balancing what hardware can be replaced by components verse by Orbital Replacement Units (ORU) or subassemblies is key. For this effort a database was created that combines mass and reliability data, called Mass and Reliability System or MaRS. The U.S. International Space Station (ISS) components are used as reference parts in the MaRS database. Using ISS components as a platform is beneficial because of the historical context and the environment similarities to a space flight mission. MaRS uses a combination of systems: International Space Station PART for failure data, Vehicle Master Database (VMDB) for ORU & components, Maintenance & Analysis Data Set (MADS) for operation hours and other pertinent data, & Hardware History Retrieval System (HHRS) for unit weights. MaRS is populated using a Visual Basic Application. Once populated, the excel spreadsheet is comprised of information on ISS components including: operation hours, random/nonrandom failures, software/hardware failures, quantity, orbital replaceable units (ORU), date of placement, unit weight, frequency of part, etc. The motivation for creating such a database will be the development of a mass/reliability parametric model to estimate mass required for replacement parts. Once complete, engineers working on future space flight missions will have access a mean time to failures and on parts along with their mass, this will be used to make proper decisions for long duration space flight missions

  14. Pulsating Stars

    NASA Astrophysics Data System (ADS)

    Catelan, M.; Smith, H. A.

    2015-03-01

    This book surveys our understanding of stars which change in brightness because they pulsate. Pulsating variable stars are keys to distance scales inside and beyond the Milky Way galaxy. They test our understanding not only of stellar pulsation theory but also of stellar structure and evolution theory. Moreover, pulsating stars are important probes of the formation and evolution of our own and neighboring galaxies. Our understanding of pulsating stars has greatly increased in recent years as large-scale surveys of pulsating stars in the Milky Way and other Local Group galaxies have provided a wealth of new observations and as space-based instruments have studied particular pulsating stars in unprecedented detail.

  15. High-Speed RaPToRS

    NASA Astrophysics Data System (ADS)

    Henchen, Robert; Esham, Benjamin; Becker, William; Pogozelski, Edward; Padalino, Stephen; Sangster, Thomas; Glebov, Vladimir

    2008-11-01

    The High-Speed Rapid Pneumatic Transport of Radioactive Samples (HS-RaPToRS) system, designed to quickly and safely move radioactive materials, was assembled and tested at the Mercury facility of the Naval Research Laboratory (NRL) in Washington D.C. A sample, which is placed inside a four-inch-diameter carrier, is activated before being transported through a PVC tube via airflow. The carrier travels from the reaction chamber to the end station where it pneumatically brakes prior to the gate. A magnetic latch releases the gate when the carrier arrives and comes to rest. The airflow, optical carrier-monitoring devices, and end gate are controlled manually or automatically with LabView software. The installation and testing of the RaPToRS system at NRL was successfully completed with transport times of less than 3 seconds. The speed of the carrier averaged 16 m/s. Prospective facilities for similar systems include the Laboratory for Laser Energetics and the National Ignition Facility.

  16. Niobium in R And (S6, 6e) and HR 1105 (S5, 3). [S star abundance

    NASA Technical Reports Server (NTRS)

    Davis, D. N.

    1985-01-01

    Lines of the first multiplet of niobium are strong in R And and HR 1105. These lines are also present in other S stars: HR 8714, R Cam, V Cnc, R CMi, and T Sgr. They are also visible in the M stars, Beta-Peg and Mu-UMa. An approximation to the abundance ratio, Nb/Fe, has been deduced from pairs of lines having nearly equal intensity. In R And, the ratio is about 200 times the solar value. It is hoped that good plates will soon be obtained for the near infrared region, so that the significant Nb/Rb abundance ratio may be determined.

  17. Massive Stars

    NASA Astrophysics Data System (ADS)

    Livio, Mario; Villaver, Eva

    2009-11-01

    Participants; Preface Mario Livio and Eva Villaver; 1. High-mass star formation by gravitational collapse of massive cores M. R. Krumholz; 2. Observations of massive star formation N. A. Patel; 3. Massive star formation in the Galactic center D. F. Figer; 4. An X-ray tour of massive star-forming regions with Chandra L. K. Townsley; 5. Massive stars: feedback effects in the local universe M. S. Oey and C. J. Clarke; 6. The initial mass function in clusters B. G. Elmegreen; 7. Massive stars and star clusters in the Antennae galaxies B. C. Whitmore; 8. On the binarity of Eta Carinae T. R. Gull; 9. Parameters and winds of hot massive stars R. P. Kudritzki and M. A. Urbaneja; 10. Unraveling the Galaxy to find the first stars J. Tumlinson; 11. Optically observable zero-age main-sequence O stars N. R. Walborn; 12. Metallicity-dependent Wolf-Raynet winds P. A. Crowther; 13. Eruptive mass loss in very massive stars and Population III stars N. Smith; 14. From progenitor to afterlife R. A. Chevalier; 15. Pair-production supernovae: theory and observation E. Scannapieco; 16. Cosmic infrared background and Population III: an overview A. Kashlinsky.

  18. RADIAL VELOCITY PLANETS DE-ALIASED: A NEW, SHORT PERIOD FOR SUPER-EARTH 55 Cnc e

    SciTech Connect

    Dawson, Rebekah I.; Fabrycky, Daniel C. E-mail: daniel.fabrycky@gmail.co

    2010-10-10

    Radial velocity measurements of stellar reflex motion have revealed many extrasolar planets, but gaps in the observations produce aliases, spurious frequencies that are frequently confused with the planets' orbital frequencies. In the case of Gl 581 d, the distinction between an alias and the true frequency was the distinction between a frozen, dead planet and a planet possibly hospitable to life. To improve the characterization of planetary systems, we describe how aliases originate and present a new approach for distinguishing between orbital frequencies and their aliases. Our approach harnesses features in the spectral window function to compare the amplitude and phase of predicted aliases with peaks present in the data. We apply it to confirm prior alias distinctions for the planets GJ 876 d and HD 75898 b. We find that the true periods of Gl 581 d and HD 73526 b/c remain ambiguous. We revise the periods of HD 156668 b and 55 Cnc e, which were afflicted by daily aliases. For HD 156668 b, the correct period is 1.2699 days and the minimum mass is (3.1 {+-} 0.4) M{sub +}. For 55 Cnc e, the correct period is 0.7365 days-the shortest of any known planet-and the minimum mass is (8.3 {+-} 0.3) M{sub +}. This revision produces a significantly improved five-planet Keplerian fit for 55 Cnc, and a self-consistent dynamical fit describes the data just as well. As radial velocity techniques push to ever-smaller planets, often found in systems of multiple planets, distinguishing true periods from aliases will become increasingly important.

  19. FPGA-based fused smart-sensor for tool-wear area quantitative estimation in CNC machine inserts.

    PubMed

    Trejo-Hernandez, Miguel; Osornio-Rios, Roque Alfredo; de Jesus Romero-Troncoso, Rene; Rodriguez-Donate, Carlos; Dominguez-Gonzalez, Aurelio; Herrera-Ruiz, Gilberto

    2010-01-01

    Manufacturing processes are of great relevance nowadays, when there is a constant claim for better productivity with high quality at low cost. The contribution of this work is the development of a fused smart-sensor, based on FPGA to improve the online quantitative estimation of flank-wear area in CNC machine inserts from the information provided by two primary sensors: the monitoring current output of a servoamplifier, and a 3-axis accelerometer. Results from experimentation show that the fusion of both parameters makes it possible to obtain three times better accuracy when compared with the accuracy obtained from current and vibration signals, individually used. PMID:22319304

  20. FPGA-Based Fused Smart-Sensor for Tool-Wear Area Quantitative Estimation in CNC Machine Inserts

    PubMed Central

    Trejo-Hernandez, Miguel; Osornio-Rios, Roque Alfredo; de Jesus Romero-Troncoso, Rene; Rodriguez-Donate, Carlos; Dominguez-Gonzalez, Aurelio; Herrera-Ruiz, Gilberto

    2010-01-01

    Manufacturing processes are of great relevance nowadays, when there is a constant claim for better productivity with high quality at low cost. The contribution of this work is the development of a fused smart-sensor, based on FPGA to improve the online quantitative estimation of flank-wear area in CNC machine inserts from the information provided by two primary sensors: the monitoring current output of a servoamplifier, and a 3-axis accelerometer. Results from experimentation show that the fusion of both parameters makes it possible to obtain three times better accuracy when compared with the accuracy obtained from current and vibration signals, individually used. PMID:22319304

  1. Spectroscopic orbits and variations of RS Ophiuchi

    NASA Astrophysics Data System (ADS)

    Brandi, E.; Quiroga, C.; Mikołajewska, J.; Ferrer, O. E.; García, L. G.

    2009-04-01

    Aims: The aims of our study are to improve the orbital elements of the giant and to derive the spectroscopic orbit for the white dwarf companion of the symbiotic system RS Oph. Spectral variations related to the 2006 outburst are also studied. Methods: We performed an analysis of about seventy optical and near infrared spectra of RS Oph that were acquired between 1998 and June 2008. The spectroscopic orbits were obtained by measuring the radial velocities of the cool component absorption lines and the broad Hα emission wings, which seem to be associated with the hot component. A set of cF-type absorption lines were also analyzed for a possible connection with the hot component motion. Results: A new period of 453.6 days and a mass ratio, q = M_g/Mh = 0.59 ± 0.05 were determined. Assuming a massive white dwarf as the hot component (Mh = 1.2-1.4 M⊙) the red giant mass is Mg = 0.68-0.80 M⊙ and the orbit inclination, i = 49°-52°. The cF-type lines are not associated with either binary component, and are most likely formed in the material streaming towards the hot component. We also confirm the presence of the Li I doublet in RS Oph and its radial velocities fit very well to the M-giant radial velocity curve. Regardless of the mechanism involved to produce lithium, its origin is most likely from within the cool giant rather than material captured by the giant at the time of the nova explosion. The quiescent spectra reveal a correlation of the H I and He I emission line fluxes with the monochromatic magnitudes at 4800 Å, indicating that the hot component activity is responsible for those flux variations. We also discuss the spectral characteristics around 54-55 and 240 days after the 2006 outburst. In April 2006 most of the emission lines present a broad pedestal with a strong and narrow component at about -20 km s-1 and two other extended emission components at -200 and +150 km s-1. These components could originate in a bipolar gas outflow supporting the model of a bipolar shock-heated shell expanding through the cool component wind perpendicularly to the binary orbital plane. Our observations also indicate that the cF absorption system was disrupted during the outburst, and restored about 240 days after the outburst, which is consistent with the resumption of accretion.

  2. Effect of a gelatin-based edible coating containing cellulose nanocrystals (CNC) on the quality and nutrient retention of fresh strawberries during storage

    NASA Astrophysics Data System (ADS)

    Fakhouri, F. M.; Casari, A. C. A.; Mariano, M.; Yamashita, F.; Innocnentini Mei, L. H.; Soldi, V.; Martelli, S. M.

    2014-08-01

    Strawberry is a non-climacteric fruit with a very short postharvest shelf-life. Loss of quality in this fruit is mostly due to its relatively high metabolic activity and sensitivity to fungal decay, meanly grey mold (Botrytis cinerea). In this study, the ability of gelatin coatings containing cellulose nanocrystals (CNC) to extend the shelf-life of strawberry fruit (Fragaria ananassa) over 8 days were studied. The filmogenic solution was obtained by the hydration of 5 g of gelatin (GEL) in 100 mL of distillated water containing different amounts of CNC dispersion (10 mg CNC/g of GEL or 50 mg of CNC/g of GEL) for 1 hour at room temperature. After this period, the solution was heated to 70 °C and maintained at this temperature for 10 minutes. The plasticizer (glycerol) (10g/100g of the GEL) was then added with constant, gentle stirring in order to avoid forming air bubbles and also to avoid gelatin denaturation until complete homogenization. Strawberries (purchased at the local market) were immersed in the filmogenic solution for 1 minute and after coated were dried at 15 °C by 24 hours. The strawberries were then kept under refrigeration and characterized in terms of their properties (weight loss, ascorbic acid content, titratable acidity, water content). The results have shown that samples covered with GEL/CNC had a significant improvement in its shelf- life. For instance, for the control sample (without coating) the weight loss after 8 days of storage was around 65%, while covered samples loss in the range of 31-36%. Edible coating was also effective in the retention of ascorbic acid (AA) in the strawberries, while control sample presented a fast decay in the AA content, covered samples showed a slow decay in the AA concentration. Moreover, the use of GEL/CNC edible coating had an antimicrobial effect in the fruits.

  3. RaPToRS Sample Delivery System

    NASA Astrophysics Data System (ADS)

    Henchen, Robert; Shibata, Kye; Krieger, Michael; Pogozelski, Edward; Padalino, Stephen; Glebov, Vladimir; Sangster, Craig

    2010-11-01

    At various labs (NIF, LLE, NRL), activated material samples are used to measure reaction properties. The Rapid Pneumatic Transport of Radioactive Samples (RaPToRS) system quickly and safely moves these radioactive samples through a closed PVC tube via airflow. The carrier travels from the reaction chamber to the control and analysis station, pneumatically braking at the outlet. A reversible multiplexer routes samples from various locations near the shot chamber to the analysis station. Also, the multiplexer allows users to remotely load unactivated samples without manually approaching the reaction chamber. All elements of the system (pneumatic drivers, flow control valves, optical position sensors, multiplexers, Geiger counters, and release gates at the analysis station) can be controlled manually or automatically using a custom LabVIEW interface. A prototype is currently operating at NRL in Washington DC. Prospective facilities for Raptors systems include LLE and NIF.

  4. Genetic Variants of VEGF (rs201963 and rs3025039) and KDR (rs7667298, rs2305948, and rs1870377) Are Associated with Glioma Risk in a Han Chinese Population: a Case-Control Study.

    PubMed

    Zhang, Jiannan; Yang, Jian; Chen, Yuqing; Mao, Qin; Li, Shanquan; Xiong, Wenhao; Lin, Yingying; Chen, Jie; Ge, Jianwei

    2016-05-01

    A glioma is the most common type of brain tumor that accounts for nearly 80 % of brain cancers. Vascular endothelial growth factor (VEGF) and its receptor, the kinase insert domain receptor (KDR), are involved in the angiogenesis of cancers. In this study, we investigate whether the polymorphisms of VEGF and KDR are associated with a glioma risk. Blood samples were collected from 477 glioma patients and 477 healthy controls. Five tag-single nucleotide polymorphisms (SNPs) of KDR were obtained from the HapMap database, and eight tag-SNPs of VEGF were selected based on previous studies. After extraction of genomic DNAs by a Qiagen DNA blood kit, the SNPs of VEGF and KDR were genotyped with a Sequenom MassArray iPLEX platform and further analyzed with matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry. The odds ratios and their 95 % confidence interval (95 % CI) were used to assess the association between VEGF, KDR polymorphisms, and glioma risks with the aid of SPSS 13.0 software. The haplotype analysis demonstrated that two SNPs of VEGF [rs3025039 (C>T), rs2010963 (G>C)] could elevate the susceptibility to a glioma in the homozygous model [odds ratio (OR) = 3.13 (95 % confidence interval (CI) 1.30-7.49, P = 0.007) and OR = 1.58 (95 % CI 1.07-2.34, P = 0.022), respectively], dominant model [OR = 1.38 (95 % CI 1.04-1.84, P = 0.025) and OR = 1.32 (95 % CI 1.01-1.72, P = 0.043), respectively], and allelic model [OR = 1.43 (95 % CI 1.11-1.84, P = 0.005) and OR = 1.24 (95 % CI 1.04-1.50, P = 0.019), respectively]. Furthermore, three SNPs of KDR [rs7667298 (A>G), rs2305948 (C>T), rs1870377 (T>A)] were also assumed to be associated with an increased risk of a glioma in the homozygous [OR = 1.93 (95 % CI 1.30-2.86, P = 0.001), OR = 2.56 (95 % CI 1.28-5.11, P = 0.006), and OR = 1.52 (95 % CI 1.00-2.31, P = 0.049), respectively], dominant [OR = 1.52 (95 % CI 1.16-1.98, P = 0.002), OR = 1.41 (95 % CI 1.05-1.87, P = 0.020), and OR = 1.48 (95 % CI 1.13-1.93, P = 0.004), respectively], and allele models [OR = 1.39 (95 % CI 1.15-1.67, P = 0.001), OR = 1.47 (95 % CI 1.14-1.89, P = 0.002), and OR = 1.27 (95 % CI 1.05-1.52, P = 0.013), respectively]. The genetic polymorphisms of VEGF [rs3025039 (C>T), rs2010963 (G>C)] and KDR [rs7667298 (A>G), rs2305948 (C>T), rs1870377 (T>A)] increased glioma susceptibility in a Chinese population, suggesting the possibility of VEGF and KDR as genetic markers for glioma. Additional functional and association studies with different ethnic groups included are needed to further confirm our results. PMID:26093379

  5. An RS-170 to 700 frame per second CCD camera

    SciTech Connect

    Albright, K.L.; King, N.S.P.; Yates, G.J.; McDonald, T.E.; Turko, B.T.

    1993-08-01

    A versatile new camera, the Los Alamos National Laboratory (LANL) model GY6, is described. It operates at a wide variety of frame rates, from RS-170 to 700 frames per second. The camera operates as an NTSC compatible black and white camera when operating at RS-170 rates. When used for variable high-frame rates, a simple substitution is made of the RS-170 sync/clock generator circuit card with a high speed emitter-coupled logic (ECL) circuit card.

  6. Pulsations and metallicity of the pre-main sequence eclipsing spectroscopic binary RS Cha

    NASA Astrophysics Data System (ADS)

    Alecian, E.; Catala, C.; van't Veer-Menneret, C.; Goupil, M.-J.; Balona, L.

    2005-11-01

    We present new spectroscopic observations of the pre-main sequence eclipsing spectroscopic binary RS Cha. A sample of 174 spectra were obtained with the GIRAFFE spectrograph at the SAAO at 32 000 resolution. The radial velocity curves derived from these spectra were combined with previous observations spanning a period of about 30 years to correct the ephemeris of the system, and the result indicates that the orbital period is not constant. Residuals of the binary radial velocity curve for both components with amplitudes up to a few km s-1 and periods on the order of 1 h are clearly seen in our data, which we interpret as the signatures of delta-Scuti type pulsations. We revisited the masses of both components and determined the surface metallicity Z of both components of the RS Cha system by fitting synthetic spectra to observed spectra in a set of selected spectral regions. The synthetic spectra are calculated with the SYNTH code using stellar atmosphere models computed with the Kurucz ATLAS 9 code, along with a list of lines obtained from the VALD database. A selection of the best spectra and the most relevant spectral regions allowed us to determine Z = 0.028 ± 0.005. We also derived new values of v sin i: 64 ± 6 km s-1 and 70 ± 6 km s-1 for the primary and the secondary star, respectively. Finally, we observationally confirm that the RS Cha system is a synchronized and circularized system.

  7. The radish defensins RsAFP1 and RsAFP2 act synergistically with caspofungin against Candida albicans biofilms.

    PubMed

    Vriens, Kim; Cools, Tanne L; Harvey, Peta J; Craik, David J; Braem, Annabel; Vleugels, Jozef; Coninck, Barbara De; Cammue, Bruno P A; Thevissen, Karin

    2016-01-01

    The radish defensin RsAFP2 was previously characterized as a peptide with potent antifungal activity against several plant pathogenic fungi and human pathogens, including Candida albicans. RsAFP2 induces apoptosis and impairs the yeast-to-hypha transition in C. albicans. As the yeast-to-hypha transition is considered important for progression to mature biofilms, we analyzed the potential antibiofilm activity of recombinant (r)RsAFP2, heterologously expressed in Pichia pastoris, against C. albicans biofilms. We found that rRsAFP2 prevents C. albicans biofilm formation with a BIC-2 (i.e., the minimal rRsAFP2 concentration that inhibits biofilm formation by 50% as compared to control treatment) of 1.65 ± 0.40mg/mL. Moreover, biofilm-specific synergistic effects were observed between rRsAFP2 doses as low as 2.5μg/mL to 10μg/mL and the antimycotics caspofungin and amphotericin B, pointing to the potential of RsAFP2 as a novel antibiofilm compound. In addition, we characterized the solution structure of rRsAFP2 and compared it to that of RsAFP1, another defensin present in radish seeds. These peptides have similar amino acid sequences, except for two amino acids, but rRsAFP2 is more potent than RsAFP1 against planktonic and biofilm cultures. Interestingly, as in case of rRsAFP2, also RsAFP1 acts synergistically with caspofungin against C. albicans biofilms in a comparable low dose range as rRsAFP2. A structural comparison of both defensins via NMR analysis revealed that also rRsAFP2 adopts the typical cysteine-stabilized αβ-motif of plant defensins, however, no structural differences were found between these peptides that might result in their differential antifungal/antibiofilm potency. This further suggests that the conserved structure of RsAFP1 and rRsAFP2 bears the potential to synergize with antimycotics against C. albicans biofilms. PMID:26592804

  8. Association analysis of APOA5 rs662799 and rs3135506 polymorphisms with obesity in Moroccan patients.

    PubMed

    Lakbakbi El Yaagoubi, F; Charoute, H; Bakhchane, A; Ajjemami, M; Benrahma, H; Errouagui, A; Kandil, M; Rouba, H; Barakat, A

    2015-12-01

    The aim of the present study is to explore the association between the APOA5 polymorphisms and haplotypes with obesity in Moroccan patients. The study was performed in 459 subjects, Obese (n=164) and non-obese (n=295). All subjects were genotyped for the APOA5 -1131T>C (rs662799) and c.56C>G (rs3135506) polymorphisms. The contribution of APOA5 polymorphisms and haplotypes in the increased risk of obesity were explored using logistic regression analyses. The -1131T>C and c.56C>G polymorphisms were significantly associated with obesity. Both polymorphisms were strongly associated with increased BMI. Analysis of constructed haplotypes showed a significant association between CG haplotype and susceptibility to obesity (OR [95%CI]=3.09 [1.93-4.97]; P<0.001). These results support a potential role for APOA5 common variants and related haplotypes as risk factors for obesity. PMID:26524954

  9. Computer numerically controlled (CNC) aspheric shaping with toroidal Wheels (Abstract Only)

    NASA Astrophysics Data System (ADS)

    Ketelsen, D.; Kittrell, W. C.; Kuhn, W. M.; Parks, R. E.; Lamb, George L.; Baker, Lynn

    1987-01-01

    Contouring with computer numerically controlled (CNC) machines can be accomplished with several different tool geometries and coordinated machine axes. To minimize the number of coordinated axes for nonsymmetric work to three, it is common practice to use a spherically shaped tool such as a ball-end mill. However, to minimize grooving due to the feed and ball radius, it is desirable to use a long ball radius, but there is clearly a practical limit to ball diameter with the spherical tool. We have found that the use of commercially available toroidal wheels permits long effective cutting radii, which in turn improve finish and minimize grooving for a set feed. In addition, toroidal wheels are easier than spherical wheels to center accurately. Cutting parameters are also easier to control because the feed rate past the tool does not change as the slope of the work changes. The drawback to the toroidal wheel is the more complex calculation of the tool path. Of course, once the algorithm is worked out, the tool path is as easily calculated as for a spherical tool. We have performed two experiments with the Large Optical Generator (LOG) that were ideally suited to three-axis contouring--surfaces that have no axis of rotational symmetry. By oscillating the cutting head horizontally or vertically (in addition to the motions required to generate the power of the surface) , and carefully coordinating those motions with table rotation, the mostly astigmatic departure for these surfaces is produced. The first experiment was a pair of reflector molds that together correct the spherical aberration of the Arecibo radio telescope. The larger of these was 5 m in diameter and had a 12 cm departure from the best-fit sphere. The second experiment was the generation of a purely astigmatic surface to demonstrate the feasibility of producing axially symmetric asphe.rics while mounted and rotated about any off-axis point. Measurements of the latter (the first experiment had relatively loose tolerances) indicate an accuracy only 3 or 4 times that achieved by conventional two-axis contouring (10 AM as opposed to 3 pm rms) The successful completion of these projects demonstrates the successful application of three-axis contouring with the LOG. Toroidal cutters have also solved many of the drawbacks of spherical wheels. Work remains to be done in improving machine response and decreasing the contribution of backlash errors.

  10. Ultraprecision, high stiffness CNC grinding machines for ductile mode grinding of brittle materials

    NASA Astrophysics Data System (ADS)

    McKeown, Patrick A.; Carlisle, Keith; Shore, Paul; Read, R. F.

    1990-10-01

    Under certain controlled conditions it is now possible to machine brittle materials such as glasses and ceramics using single or multi-point diamond tools (grinding), so that material is removed by plastic flow, leaving crack-free surfaces. This process is called 'shear' or 'ductile' mode grinding. It represents a major breakthrough in modern manufacturing engineering since it promises to enable: - complex optical components, both transmission and reflecting to be generated by advanced CNC machines with very little (or even zero) subsequent polishing. - complex shaped components such as turbine blades, nozzle guide vanes, etc. to be finish machined after near net shape forming, to high precision in advanced ceramics such as silicon nitride, without inducing micro-cracking and thus lowering ultimate rupture strength and fatigue life. Ductile mode "damage free" grinding occurs when the volume of materials stressed by each grit of the grinding wheel is small enough to yield rather than exhibit brittle fracture, i.e. cracking. In practice, this means maintaining the undeformed chip thickness to below the ductile-brittle transition value; this varies from material to material but is generally in the order of 0.1 pm or 100 nm, (hence the term "nanogrinding" is sometimes used) . Thus the critical factors for operating successfully in the ductile regime are machine system accuracy and dynamic stiffness between each grit and the workpiece. In detail this means: (i) High precision 'truing' of the diamond grits, together with dressing of the wheel bond to ensure adequate ' openness'; (ii) Design and build of the grinding wheel spindle with very high dynamic stiffness; error motions, radial and axial, must be considerably less than 100 nfl. (iii) Design and build of the workpiece carriage motion system with very high dynamic stiffness; error motions, linear or rotary, must be well within 100 nm. (iv) Smooth, rumble-free, high-stiffness servo-drives controlling the motions which form the chip. In general, and as a rule of thumb, a machine "loop-stiffness" (between tool and workpiece) not less than 300 N,4im (static) is necessary.

  11. Genetic Variations rs11892031 and rs401681 Are Associated with Bladder Cancer Risk in a Chinese Population

    PubMed Central

    Zhang, Yu; Sun, Yan; Chen, Tao; Hu, Hailong; Xie, Wanqin; Qiao, Zhihui; Ding, Na; Xie, Linguo; Li, Sheng; Wang, Wenlong; Xing, Chen; Wang, Yihan; Qie, Yunkai; Wu, Changli

    2014-01-01

    Genome-wide association studies (GWAS) have identified a number of genetic variants associated with risk of bladder cancer in populations of European descent. Here, we assessed association of two of these variants, rs11892031 (2q37.1 region) and rs401681 (5p15.33 region) in a Chinese case-control study, which included 367 bladder cancer cases and 420 controls. We found that the AC genotype of rs11892031 was associated with remarkably decreased risk of bladder cancer (adjusted odds ratio (OR), 0.27; 95% confidence interval (CI), 0.09–0.81; p = 0.019), compared with the AA genotype of rs11892031; and that CT/CC genotypes of rs401681 were associated with significantly increased risk of bladder cancer (adjusted OR, 1.79; 95% CI, 1.10–2.91; p = 0.02), compared with the TT genotype of rs401681. We further conducted stratification analysis to examine the correlation between single nucleotide polymorphism (SNP) rs11892031/rs401681 and tumor grade/stage. Results showed that heterogeneity in ORs of tumor categories was not significant for either rs11892031 or rs401681 (p > 0.05), indicating that the two SNPs seemingly do not associate with tumor grade and stage of bladder cancer in our study population. The present study suggests that the SNPs rs11892031 and rs401681 are associated with bladder cancer risk in a Chinese population. Future analyses will be conducted with more participants recruited in a case-control study. PMID:25347272

  12. Remastering the RV Classics: Self-Consistent Dynamical Models for the 55 Cnc and GJ 876 Planetary Systems

    NASA Astrophysics Data System (ADS)

    Nelson, Benjamin E.; Ford, E. B.; Wright, J.; Fischer, D.

    2014-01-01

    Over the past two decades, radial velocity (RV) observations have uncovered a handful of dynamically rich exoplanet systems. In particular, the 55 Cnc and GJ 876 systems have 4+ planets with some of them displaying planet-planet interactions on the observing timescale. In turn, this makes the posterior distributions of these systems oddly shaped and extremely difficult to sample from, especially when employing a Newtonian model. We apply our Radial velocity Using N-body Differential evolution Markov chain Monte Carlo code (RUN DMC; Nelson et al. 2013, submitted) to these two landmark systems. For 55 Cnc, we investigate the orbital architecture based on a cumulative 1418 RV observations from various sources and transit constraints from Winn et al. 2011. We find planets "b" and "c" are apsidally aligned but not in a mean-motion resonance, and the orbital stability of the system is sensitive to the orbital properties of planet "f". For GJ 876, we analyze the Keck HIRES (Rivera et al. 2010) and HARPS (Correia et al. 2010) data to constrain the distribution of the Laplace argument and mutual inclinations amongst planet pairs based on both the RVs and assumption of long-term stability.

  13. A Modern Take on the RV Classics: N-body Analysis of GJ 876 and 55 Cnc

    NASA Astrophysics Data System (ADS)

    Nelson, Benjamin E.; Ford, E. B.; Wright, J.

    2013-01-01

    Over the past two decades, radial velocity (RV) observations have uncovered a diverse population of exoplanet systems, in particular a subset of multi-planet systems that exhibit strong dynamical interactions. To extract the model parameters (and uncertainties) accurately from these observations, one requires self-consistent n-body integrations and must explore a high-dimensional 7 x number of planets) parameter space, both of which are computationally challenging. Utilizing the power of modern computing resources, we apply our Radial velocity Using N-body Differential Evolution Markov Chain Monte Carlo code (RUN DEMCMC) to two landmark systems from early exoplanet surveys: GJ 876 and 55 Cnc. For GJ 876, we analyze the Keck HIRES (Rivera et al. 2010) and HARPS (Correia et al. 2010) data and constrain the distribution of the Laplace argument. For 55 Cnc, we investigate the orbital architecture based on a cumulative 1086 RV observations from various sources and transit constraints from Winn et al. 2011. In both cases, we also test for long-term orbital stability.

  14. Site-Selective Modification of Cellulose Nanocrystals with Isophorone Diisocyanate and Formation of Polyurethane-CNC Composites.

    PubMed

    Girouard, Natalie M; Xu, Shanhong; Schueneman, Gregory T; Shofner, Meisha L; Meredith, J Carson

    2016-01-20

    The unequal reactivity of the two isocyanate groups in an isophorone diisocyante (IPDI) monomer was exploited to yield modified cellulose nanocrystals (CNCs) with both urethane and isocyanate functionality. The chemical functionality of the modified CNCs was verified with ATR-FTIR analysis and elemental analysis. The selectivity for the secondary isocyanate group using dibutyl tin dilaurate (DBTDL) as the reaction catalyst was confirmed with (13)C NMR. The modified CNCs showed improvements in the onset of thermal degradation by 35 °C compared to the unmodified CNCs. Polyurethane composites based on IPDI and a trifunctional polyether alcohol were synthesized using unmodified (um-CNC) and modified CNCs (m-CNC). The degree of nanoparticle dispersion was qualitatively assessed with polarized optical microscopy. It was found that the modification step facilitated superior nanoparticle dispersion compared to the um-CNCs, which resulted in increases in the tensile strength and work of fracture of over 200% compared to the neat matrix without degradation of elongation at break. PMID:26713564

  15. RORA gene rs12912233 and rs880626 polymorphisms and their interaction with SCN1A rs3812718 in the risk of epilepsy: a case-control study in Malaysia.

    PubMed

    Haerian, Batoul Sadat; Sha'ari, Hidayati Mohd; Tan, Hui Jan; Fong, Choong Yi; Wong, Sau Wei; Ong, Lai Choo; Raymond, Azman Ali; Tan, Chong Tin; Mohamed, Zahurin

    2015-04-01

    RAR-related orphan receptors A (RORA) and B (RORB) and voltage-gated sodium channel type 1 (SCN1A) genes play critical roles in the regulation of the circadian clock. Evidence has shown an association of RORA and RORB polymorphisms with susceptibility to autism and depression. Hence, we tested the association of RORA rs12912233, rs16943429, rs880626, rs2290430, and rs12900948; RORB rs1157358, rs7022435, rs3750420, and rs3903529; and SCN1A rs3812718 with epilepsy risk in the Malaysians. DNA was genotyped in 1789 subjects (39% epilepsy patients) by using MassARRAY (Sequenom). Significant association was obtained for rs12912233 in Malaysian Chinese (p=0.003). Interaction between rs12912233-rs880626 and rs3812718 was associated with the epilepsy risk in the subjects overall (p=0.001). Results show that RORA rs12912233 alone might be a possible risk variant for epilepsy in Malaysian Chinese, but that, together with RORA rs880626 and SCN1A rs3812718, this polymorphism may have a synergistic effect in the epilepsy risk in Malaysians. PMID:25668517

  16. Association of APOA5 rs662799 and rs3135506 polymorphisms with arterial hypertension in Moroccan patients

    PubMed Central

    2014-01-01

    Background The goal of the study is to investigate the association between the APOA5 polymorphisms and haplotypes with Arterial Hypertension (AHT) in Moroccan patients. Methods The study was performed in 283 subjects, 149 patients with AHT and 134 controls. All subjects were genotyped for the APOA5 -1131 T > C (rs662799), 56C > G (rs3135506) and c.553G > T (rs2075291) polymorphisms. Results There was a strong association between -1131 T > C and 56C > G polymorphisms with AHT. The -1131 T > C and 56C > G polymorphisms were significantly associated with increased systolic blood pressure (SBP) and triglycerides (TG) levels. There were 4 haplotypes with a frequency higher than 5%, constructed from APOA5 polymorphisms, with the following order: -1131 T > C, 56C > G and c.553G > T. Haplotype H1 (TCG) was associated with decreased risk of AHT, whereas the haplotypes H2 (CCG) and H4 (CGG) were significantly associated with an increased risk of AHT. Carriers of H1 haplotype had a lower SBP and DBP and TG. In contrast, significant elevated SBP, DBP and TG were found in H4 haplotypes carriers. Conclusions Our data demonstrate for the first time that several common SNPs in the APOA5 gene and their haplotypes are closely associated with modifications of blood pressure and serum lipid parameters in the AHT patient. PMID:24684850

  17. Mg(2+) signalling defines the group A streptococcal CsrRS (CovRS) regulon.

    PubMed

    Gryllos, Ioannis; Grifantini, Renata; Colaprico, Annalisa; Jiang, Shengmei; Deforce, Emelia; Hakansson, Anders; Telford, John L; Grandi, Guido; Wessels, Michael R

    2007-08-01

    CsrRS (or CovRS) is a two-component system implicated in the control of multiple virulence determinants in the important human pathogen, group A Streptococcus (GAS). Earlier studies suggested that extracellular Mg(2+) signalled through the presumed sensor histidine kinase, CsrS. We now confirm those findings, as complementation of a csrS mutant restored Mg(2+)-dependent gene regulation. Moreover, we present strong evidence that Mg(2+) signals through CsrS to regulate an extensive and previously undefined repertoire of GAS genes. The effect of Mg(2+) on regulation of global gene expression was evaluated using genomic microarrays in an M-type 3 strain of GAS and in an isogenic csrS mutant. Unexpectedly, of the 72 genes identified in the Mg(2+)-stimulated CsrRS regulon, 42 were absent from the CsrR regulon (the latter being defined by comparison of wild-type and CsrR mutant transcriptomes at low Mg(2+)). We observed CsrS-dependent regulation of 72 of the 73 genes whose expression changed in response to elevated extracellular Mg(2+) in wild-type bacteria, a result that identifies CsrS as the principal, if not exclusive, sensor for extracellular Mg(2+) in GAS. To our knowledge, this study is the first to characterize global gene regulation by a GAS two-component system in response to a specific environmental stimulus. PMID:17608796

  18. Polymorphisms in Four Genes (KCNQ1 rs151290, KLF14 rs972283, GCKR rs780094 and MTNR1B rs10830963) and Their Correlation with Type 2 Diabetes Mellitus in Han Chinese in Henan Province, China

    PubMed Central

    Gao, Kaiping; Wang, Jinjin; Li, Linlin; Zhai, Yujia; Ren, Yongcheng; You, Haifei; Wang, Bingyuan; Wu, Xuli; Li, Jianna; Liu, Zichen; Li, Xiong; Huang, Yaxin; Luo, Xin-Ping; Hu, Dongsheng; Ohno, Kinji; Wang, Chongjian

    2016-01-01

    Genetic variants at KCNQ1 rs151290, KLF14 rs972283, GCKR rs780094 and MTNR1B rs10830963 have been associated with type 2 diabetes mellitus (T2DM), but the results are contradictory in Chinese populations. The aim of the present study was to investigate the association of these four SNPs with T2DM in a large population of Han Chinese at Henan province, China. Seven-hundred-thirty-six patients with T2DM (cases) and Seven-hundred-sixty-eight healthy glucose-tolerant controls were genotyped for KCNQ1 rs151290, KLF14 rs972283, GCKR rs780094 and MTNR1B rs10830963. The association of genetic variants in these four genes with T2DM was analyzed using multivariate logistic regression. Genotypes and allele distributions of KCNQ1 rs151290 were significantly different between the cases and controls (p < 0.05). The AC and CC genotypes and the combined AC + CC genotype of rs151290 in KCNQ1 were associated with increases risk of T2DM before (OR = 1.482, 95% CI = 1.062–2.069; p = 0.021; OR = 1.544, 95% CI = 1.097–2.172, p = 0.013; and OR = 1.509, 95% CI = 1.097–2.077, p = 0.011, respectively) and after (OR = 1.539, 95% CI = 1.015–2.332, p = 0.042; OR = 1.641, 95% CI = 1.070–2.516, p = 0.023; and OR = 1.582, 95% CI = 1.061–2.358, p = 0.024; respectively) adjustment for sex, age, anthropometric measurements, biochemical indexes, smoking and alcohol consumption. Consistent with results of genotype analysis, the C allele of rs151290 in KCNQ1 was also associated with increased risk of T2DM (OR = 1.166, 95% CI = 1.004–1.355, p = 0.045). No associations between genetic variants of KLF14 rs972283, GCKR rs780094 or MTNR1B rs10830963 and T2DM were detected. The AC and CC genotypes and the C allele of rs151290 in KCNQ1 may be risk factors for T2DM in Han Chinese in Henan province. PMID:26927145

  19. Polymorphisms in Four Genes (KCNQ1 rs151290, KLF14 rs972283, GCKR rs780094 and MTNR1B rs10830963) and Their Correlation with Type 2 Diabetes Mellitus in Han Chinese in Henan Province, China.

    PubMed

    Gao, Kaiping; Wang, Jinjin; Li, Linlin; Zhai, Yujia; Ren, Yongcheng; You, Haifei; Wang, Bingyuan; Wu, Xuli; Li, Jianna; Liu, Zichen; Li, Xiong; Huang, Yaxin; Luo, Xin-Ping; Hu, Dongsheng; Ohno, Kinji; Wang, Chongjian

    2016-01-01

    Genetic variants at KCNQ1 rs151290, KLF14 rs972283, GCKR rs780094 and MTNR1B rs10830963 have been associated with type 2 diabetes mellitus (T2DM), but the results are contradictory in Chinese populations. The aim of the present study was to investigate the association of these four SNPs with T2DM in a large population of Han Chinese at Henan province, China. Seven-hundred-thirty-six patients with T2DM (cases) and Seven-hundred-sixty-eight healthy glucose-tolerant controls were genotyped for KCNQ1 rs151290, KLF14 rs972283, GCKR rs780094 and MTNR1B rs10830963. The association of genetic variants in these four genes with T2DM was analyzed using multivariate logistic regression. Genotypes and allele distributions of KCNQ1 rs151290 were significantly different between the cases and controls (p < 0.05). The AC and CC genotypes and the combined AC + CC genotype of rs151290 in KCNQ1 were associated with increases risk of T2DM before (OR = 1.482, 95% CI = 1.062-2.069; p = 0.021; OR = 1.544, 95% CI = 1.097-2.172, p = 0.013; and OR = 1.509, 95% CI = 1.097-2.077, p = 0.011, respectively) and after (OR = 1.539, 95% CI = 1.015-2.332, p = 0.042; OR = 1.641, 95% CI = 1.070-2.516, p = 0.023; and OR = 1.582, 95% CI = 1.061-2.358, p = 0.024; respectively) adjustment for sex, age, anthropometric measurements, biochemical indexes, smoking and alcohol consumption. Consistent with results of genotype analysis, the C allele of rs151290 in KCNQ1 was also associated with increased risk of T2DM (OR = 1.166, 95% CI = 1.004-1.355, p = 0.045). No associations between genetic variants of KLF14 rs972283, GCKR rs780094 or MTNR1B rs10830963 and T2DM were detected. The AC and CC genotypes and the C allele of rs151290 in KCNQ1 may be risk factors for T2DM in Han Chinese in Henan province. PMID:26927145

  20. 108 New Variable Stars in the NSVS Database

    NASA Astrophysics Data System (ADS)

    Usatov, Maxim; Nosulchik, Artem

    2008-05-01

    In this paper we present 105 SR+L, 1 Orion T Tau and 2 RS CVn type variable stars found in the Northern Sky Variability Survey (NSVS) database. This work is designated to complement and finalize our previous publication of the Extended Catalog of Red AGB Variable Stars found in the NSVS database as is primarily designated to find SR+L stars. While the previous work employed the AOV ratio cutoff at >1.6 to pick stars showing slow variability pattern, we have manually processed all the remaining objects originally filtered out by the smaller AOV ratio and picked the ones with light curves showing obvious variability pattern. All the stars presented have no identification in General Catalogue of Variable Stars, SIMBAD and VSX databases thus most likely the stars presented are new discoveries.

  1. Neutron Stars

    NASA Technical Reports Server (NTRS)

    Cottam, J.

    2007-01-01

    Neutron stars were discovered almost 40 years ago, and yet many of their most fundamental properties remain mysteries. There have been many attempts to measure the mass and radius of a neutron star and thereby constrain the equation of state of the dense nuclear matter at their cores. These have been complicated by unknown parameters such as the source distance and burning fractions. A clean, straightforward way to access the neutron star parameters is with high-resolution spectroscopy. I will present the results of searches for gravitationally red-shifted absorption lines from the neutron star atmosphere using XMM-Newton and Chandra.

  2. Configuration control plan for the ports NCS IBM RS/6000

    SciTech Connect

    Brown, A.S.

    1996-07-01

    This document describes the actions and responsibilities for maintaining the quality and integrity of the NS software resident on the IBM RS/6000 workstation managed by the Nuclear Criticality Safety group at the Portsmouth Gaseous Diffusion Plant. This document does not address the validation of NS software packages for the RS/6000.

  3. Responding to the 5Rs: An Alternate Perspective of Slowmation

    ERIC Educational Resources Information Center

    Kidman, Gillian; Keast, Stephen; Cooper, Rebecca

    2012-01-01

    This paper is a response to Hoban and Neilsen's (2010) Five Rs model for understanding how learners engage with slowmation. An alternative model (the Learning MMAEPER Model) that builds on the 5Rs model is explained in terms of its use in secondary science preservice teacher education. To probe into the surface and deep learning that can occur

  4. Fast decoding of a d(min) = 6 RS code

    NASA Technical Reports Server (NTRS)

    Deng, H.; Costello, D. J., Jr.

    1983-01-01

    A method for high speed decoding a d sub min = 6 Reed-Solomon (RS) code is presented. Properties of the two byte error correcting and three byte error detecting RS code are discussed. Decoding using a quadratic equation is shown. Theorems and concomitant proofs are included to substantiate this decoding method.

  5. Responding to the 5Rs: An Alternate Perspective of Slowmation

    ERIC Educational Resources Information Center

    Kidman, Gillian; Keast, Stephen; Cooper, Rebecca

    2012-01-01

    This paper is a response to Hoban and Neilsen's (2010) Five Rs model for understanding how learners engage with slowmation. An alternative model (the Learning MMAEPER Model) that builds on the 5Rs model is explained in terms of its use in secondary science preservice teacher education. To probe into the surface and deep learning that can occur…

  6. 10 CFR 434.103 - Referenced standards (RS).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Referenced standards (RS). 434.103 Section 434.103 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Administration and Enforcement-General § 434.103 Referenced standards (RS)....

  7. 10 CFR 434.103 - Referenced standards (RS).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Referenced standards (RS). 434.103 Section 434.103 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Administration and Enforcement-General § 434.103 Referenced standards (RS). 103.1...

  8. 10 CFR 434.103 - Referenced standards (RS).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Referenced standards (RS). 434.103 Section 434.103 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Administration and Enforcement-General § 434.103 Referenced standards (RS)....

  9. 10 CFR 434.103 - Referenced standards (RS).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Referenced standards (RS). 434.103 Section 434.103 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Administration and Enforcement-General § 434.103 Referenced standards (RS)....

  10. 10 CFR 434.103 - Referenced standards (RS).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Referenced standards (RS). 434.103 Section 434.103 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Administration and Enforcement-General § 434.103 Referenced standards (RS)....

  11. Association of p53 rs1042522, MDM2 rs2279744, and p21 rs1801270 polymorphisms with retinoblastoma risk and invasion in a Chinese population

    PubMed Central

    Chen, Rongxin; Liu, Shu; Ye, Huijing; Li, Jiali; Du, Yi; Chen, Lingyan; Liu, Xiaoman; Ding, Yungang; Li, Qian; Mao, Yuxiang; Ai, Siming; Zhang, Ping; Ma, Wenfang; Yang, Huasheng

    2015-01-01

    Single nucleotide polymorphisms (SNPs) of p53 rs1042522, MDM2 rs2279744 and p21 rs1801270, all in the p53 pathway, which plays a crucial role in DNA damage and genomic instability, were reported to be associated with cancer risk and pathologic characteristics. This case-control study was designed to analyse the association between these SNPs and retinoblastoma (RB) in a Chinese Han population. These SNPs in 168 RB patients and 185 adult controls were genotyped using genomic DNA from venous blood. No significant difference was observed in allele or genotypic frequencies of these SNPs between Chinese RB patients and controls (all P > 0.05). However, the rs1042522 GC genotype showed a protective effect against RB invasion, as demonstrated by event-free survival (HR = 0.53, P = 0.007 for GC versus GG/CC). This effect was significant for patients with a lag time >1 month and no pre-enucleation treatment (P = 0.007 and P = 0.010, respectively), indicating an interaction between p53 rs1042522 and clinical characteristics, including lag time and pre-enucleation treatment status. Thus, the rs1042522 SNP may be associated with RB invasion in the Han Chinese population; however, further large and functional studies are needed to assess the validity of this association. PMID:26289323

  12. Unified error model based spatial error compensation for four types of CNC machining center: Part I-Singular function based unified error model

    NASA Astrophysics Data System (ADS)

    Fan, Kaiguo; Yang, Jianguo; Yang, Liyan

    2015-08-01

    To unify the error model for four types of CNC machining center, the comprehensive error model of each type of CNC machining center was established using the homogenous transformation matrix (HTM). The internal rules between the HTMs and the kinematic chains were analyzed in this research. The analysis results show that the HTM elements associated with the motion axes which are at the rear of the reference coordinate system are positive value. On the contrary, the HTM elements associated with the motion axes which are at the front of the reference coordinate system are negative value. To express these internal rules, the singular function was introduced to the HTMs. And a unified error model for four types of CNC machining center was established based on the HTM and the singular function. The unified error model includes 18 error elements which are the main factors affecting the machining accuracy of CNC machine tools. The practical results show that the unified error model is not only suitable for vertical machining center but also suitable for horizontal machining center.

  13. An open CAM system for dentistry on the basis of China-made 5-axis simultaneous contouring CNC machine tool and industrial CAM software.

    PubMed

    Lu, Li; Liu, Shusheng; Shi, Shenggen; Yang, Jianzhong

    2011-10-01

    China-made 5-axis simultaneous contouring CNC machine tool and domestically developed industrial computer-aided manufacture (CAM) technology were used for full crown fabrication and measurement of crown accuracy, with an attempt to establish an open CAM system for dental processing and to promote the introduction of domestic dental computer-aided design (CAD)/CAM system. Commercially available scanning equipment was used to make a basic digital tooth model after preparation of crown, and CAD software that comes with the scanning device was employed to design the crown by using domestic industrial CAM software to process the crown data in order to generate a solid model for machining purpose, and then China-made 5-axis simultaneous contouring CNC machine tool was used to complete machining of the whole crown and the internal accuracy of the crown internal was measured by using 3D-MicroCT. The results showed that China-made 5-axis simultaneous contouring CNC machine tool in combination with domestic industrial CAM technology can be used for crown making and the crown was well positioned in die. The internal accuracy was successfully measured by using 3D-MicroCT. It is concluded that an open CAM system for dentistry on the basis of China-made 5-axis simultaneous contouring CNC machine tool and domestic industrial CAM software has been established, and development of the system will promote the introduction of domestically-produced dental CAD/CAM system. PMID:22038364

  14. Enigmatic star EZ Pegasi - a mystery solved

    SciTech Connect

    Howell, S.B.; Bopp, B.W.

    1985-01-01

    EZ Peg, a ninth-magnitude G star that has been classified by various authors as an irregular variable, a U Gem system, and a contact binary, is shown to have all the spectroscopic and photometric characteristics of an active-chromosphere RS CVn binary. It is suggested that the reported outburst of 1943, when the spectrum appeared to be that of a B star, never occurred. The strong Ca II H and K reversals, viewed with low spectral resolution, caused the photospheric Ca II absorption to appear abnormally weak, mimicking a much earlier spectral type. 20 references.

  15. Association of BID SNPs (rs8190315 and rs2072392) and clinical features of benign prostate hyperplasia in Korean population

    PubMed Central

    Seok, Hosik; Kim, Su Kang; Yoo, Koo Han; Lee, Byung-Cheol; Kim, Young Ock; Chung, Joo-Ho

    2014-01-01

    Exercise has beneficial effect on cancer apoptosis and benign prostatic hyperplasia (BPH). The BH3 interacting domain death agonist (BID) gene expression is associated with apoptosis or cell proliferation. In this study, we investigated the association between BID single nucleotide polymorphisms (SNPs) and the development, prostate volume, and international prostate symptom score (IPSS) of BPH. In 222 BPH males and 214 controls, two SNPs in BID [rs8190315 (Ser56Gly), and rs2072392 (Asp106Asp)] were genotyped and analyzed using multiple logistic regression models. In the result, the genotype and allele frequencies of rs8190315 and rs2072392 were not associated with BPH development or IPSS, however, the allele frequencies [odd ratio (OR)= 1.90, 95% confidence interval (CI)= 1.07–3.41, P= 0.03] and genotype frequencies (in dominant model, OR= 1.94, 95% CI= 1.01–3.74, P= 0.42) of rs8190315, and the genotype frequencies of rs2072392 (in dominant model, OR= 1.94, 95% CI= 1.01–3.74, P= 0.42) were associated with increased prostate volume. We propose that rs8190315 and rs2072392 of BID may contribute to the disease severity of BPH. PMID:25610824

  16. 40 CFR 180.1114 - Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS; exemptions from the requirement of a tolerance. 180.1114 Section 180.1114 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS TOLERANCES AND EXEMPTIONS...

  17. Radio stars.

    PubMed

    Hjellming, R M; Wade, C M

    1971-09-17

    Up to the present time six classes of radio stars have been established. The signals are almost always very faint and drastically variable. Hence their discovery has owed as much to serendipity as to the highly sophisticated equipment and techniques that have been used. When the variations are regular, as with the pulsars, this characteristic can be exploited very successfully in the search for new objects as well as in the detailed study of those that are already known. The detection of the most erratically variable radio stars, the flare stars and the x-ray stars, is primarily a matter of luck and patience. In the case of the novas, one at least knows where and oughly when to look for radio emission. A very sensitive interferometer is clearly the best instrument to use in the initial detection of a radio star. The fact that weak background sources are frequently present makes it essential to prove that the position of a radio source agrees with that of a star to within a few arc seconds. The potential of radio astronomy for the study of radio stars will not be realized until more powerful instruments than those that are available today can be utilized. So far, we have been able to see only the most luminous of the radio stars. PMID:17836594

  18. CXCL12 rs266085 and TNF-α rs1799724 polymorphisms and susceptibility to cervical cancer in a Chinese population

    PubMed Central

    Yin, Geping; Zhu, Tongyu; Li, Juan; Wu, Aifang; Liang, Jing; Zhi, Yuanyuan

    2015-01-01

    Further research is required to identify single nucleotide polymorphisms (SNPs) associated with cervical cancer. The aim of this study was to assess the association of TNF-α/rs1799724 and CXCL12/rs266085 polymorphisms with susceptibility to cervical cancer in Han Chinese population in Shandong Province. 348 patients with cervical squamous cell carcinoma, including CIS (121) and invasive carcinoma (227), and 351 healthy controls. Genomic DNA was isolated from peripheral blood and genotyping for TNF-α/rs1799724 and CXCL12/rs266085 was carried out using TaqMan SNP Genotyping Assays. TNF-α/rs1799724 polymorphism showed the C-allele was less prevalent among cases as compared to controls (74.3% vs. 92.0%), while the T-allele was more prevalent among cases (P=0.000, OR=3.99, 95% C.I.: 2.90-5.51). CXCL12/rs266085 polymorphism showed the C-allele was less prevalent among cases as compared to controls (41.2% vs. 49.7%), while the T-allele was more prevalent among cases (P=0.001, OR=1.41, 95% C.I.: 1.14-1.74). The genotype and allele frequencies of these two SNPs did not differ between CIS and invasive squamous cell carcinoma (P>0.05). Moreover, the allele frequencies of rs1799724 were significantly different between controls without or with HPV infection (P<0.05). Neither the genotype nor allele frequencies of rs266085 were statistically different between HPV-negative and positive controls. TNF-α/rs1799724 and CXCL12/rs266085 polymorphisms are associated with cervical cancer. C->T polymorphism of these two SNPs and HPV infection are linked to high risk for cervical cancer. PMID:26191295

  19. Frequency of rs731236 (Taql), rs2228570 (Fok1) of Vitamin-D Receptor (VDR) gene in Emirati healthy population

    PubMed Central

    Osman, Enas; Al Anouti, Fatme; El ghazali, Gehad; Haq, Afrozul; Mirgani, Rajaa; Al Safar, Habiba

    2015-01-01

    Vitamin D is getting more attention everyday due to its importance in maintaining bone and calcium homeostasis, cellular proliferation, differentiation and immune response. Vitamin D is derived from diet or elicited in the skin by the activation of 7-dehydrocholesterol, which is an inert molecule that must be activated by ultraviolet light to form pre-vitamin D3. Recent studies connected the gene encoding for vitamin D (VDR) to the genetic control of bone mass and other diseases. As VDR SNPs have been associated with several disorders and diseases, it's important to investigate the allelic and genotypic distribution among populations. The aim of this study is to determine the frequency of rs731236 (Taq1) and rs2228570 (Fok1) variants in healthy Emirati individuals and compare their genotype and allele distribution with other populations. In this study 282 (female, 187; male, 95) unrelated healthy UAE nationals were involved. Two hundreds and eight two DNA samples been collected to genotype rs731236 (Taq1) and rs2228570 (Fok1) VDR SNPs. Our results indicate that the distribution of the alleles and genotypes of rs731236 (Taq1) and rs2228570 (Fok1) vary considerably in different populations. In the Emirati population the distribution of rs731236 (Taq1) and rs2228570 (Fok1) were AA 38%, AG 42%, GG 20% and AA 27%, AG 42%, GG 31% respectively. The Emirati population genotype and allele distribution of rs731236 (Taq1) and rs2228570 (Fok1) had no difference with Caucasians from USA and France. However, there was significant difference with Asian populations. PMID:26504744

  20. RS-34 Phoenix (Peacekeeper Post Boost Propulsion System) Utilization Study

    NASA Technical Reports Server (NTRS)

    Esther, Elizabeth A.; Kos, Larry; Bruno, Cy

    2012-01-01

    The Advanced Concepts Office (ACO) at the NASA Marshall Space Flight Center (MSFC) in conjunction with Pratt & Whitney Rocketdyne conducted a study to evaluate potential in-space applications for the Rocketdyne produced RS-34 propulsion system. The existing RS-34 propulsion system is a remaining asset from the decommissioned United States Air Force Peacekeeper ICBM program; specifically the pressure-fed storable bipropellant Stage IV Post Boost Propulsion System, renamed Phoenix. MSFC gained experience with the RS-34 propulsion system on the successful Ares I-X flight test program flown in October 2009. RS-34 propulsion system components were harvested from stages supplied by the USAF and used on the Ares I-X Roll control system (RoCS). The heritage hardware proved extremely robust and reliable and sparked interest for further utilization on other potential in-space applications. Subsequently, MSFC is working closely with the USAF to obtain all the remaining RS-34 stages for re-use opportunities. Prior to pursuit of securing the hardware, MSFC commissioned the Advanced Concepts Office to understand the capability and potential applications for the RS-34 Phoenix stage as it benefits NASA, DoD, and commercial industry. Originally designed, the RS-34 Phoenix provided in-space six-degrees-of freedom operational maneuvering to deploy multiple payloads at various orbital locations. The RS-34 Phoenix Utilization Study sought to understand how the unique capabilities of the RS-34 Phoenix and its application to six candidate missions: 1) small satellite delivery (SSD), 2) orbital debris removal (ODR), 3) ISS re-supply, 4) SLS kick stage, 5) manned GEO servicing precursor mission, and an Earth-Moon L-2 Waypoint mission. The small satellite delivery and orbital debris removal missions were found to closely mimic the heritage RS-34 mission. It is believed that this technology will enable a small, low-cost multiple satellite delivery to multiple orbital locations with a single boost. For both the small satellite delivery and the orbital debris mission candidates, the RS-34 Phoenix requires the least amount of modification to the existing hardware. The results of the RS-34 Phoenix Utilization Study show that the system is technically sufficient to successfully support all of the missions analyzed

  1. RS-34 Phoenix (Peacekeeper Post Boost Propulsion System) Utilization Study

    NASA Technical Reports Server (NTRS)

    Esther, Elizabeth A.; Kos, Larry; Burnside, Christopher G.; Bruno, Cy

    2013-01-01

    The Advanced Concepts Office (ACO) at the NASA Marshall Space Flight Center (MSFC) in conjunction with Pratt & Whitney Rocketdyne conducted a study to evaluate potential in-space applications for the Rocketdyne produced RS-34 propulsion system. The existing RS-34 propulsion system is a remaining asset from the de-commissioned United States Air Force Peacekeeper ICBM program, specifically the pressure-fed storable bipropellant Stage IV Post Boost Propulsion System, renamed Phoenix. MSFC gained experience with the RS-34 propulsion system on the successful Ares I-X flight test program flown in October 2009. RS-34 propulsion system components were harvested from stages supplied by the USAF and used on the Ares I-X Roll control system (RoCS). The heritage hardware proved extremely robust and reliable and sparked interest for further utilization on other potential in-space applications. MSFC is working closely with the USAF to obtain RS-34 stages for re-use opportunities. Prior to pursuit of securing the hardware, MSFC commissioned the Advanced Concepts Office to understand the capability and potential applications for the RS-34 Phoenix stage as it benefits NASA, DoD, and commercial industry. As originally designed, the RS-34 Phoenix provided in-space six-degrees-of freedom operational maneuvering to deploy multiple payloads at various orbital locations. The RS-34 Phoenix Utilization Study sought to understand how the unique capabilities of the RS-34 Phoenix and its application to six candidate missions: 1) small satellite delivery (SSD), 2) orbital debris removal (ODR), 3) ISS re-supply, 4) SLS kick stage, 5) manned GEO servicing precursor mission, and an Earth-Moon L-2 Waypoint mission. The small satellite delivery and orbital debris removal missions were found to closely mimic the heritage RS-34 mission. It is believed that this technology will enable a small, low-cost multiple satellite delivery to multiple orbital locations with a single boost. For both the small satellite delivery and the orbital debris mission candidates, the RS-34 Phoenix requires the least amount of modification to the existing hardware. The results of the RS-34 Phoenix Utilization Study show that the system is technically sufficient to successfully support all of the missions analyzed.

  2. Enantioselective degradation of (2RS,3RS)-paclobutrazol in peach and mandarin under field conditions.

    PubMed

    Wang, Xiangyun; Qi, Peipei; Yang, Guiling; Wang, Xinquan; Zhang, Hu; Xu, Hao; Wang, Zhiwei; Wang, Qiang

    2014-08-01

    In this study we investigated the enantioselective degradation of (2RS,3RS)-paclobutrazol in peach and mandarin fruits under field conditions after foliar treatment at 500 mg active ingredient/L using a Lux Cellulose-1 chiral column on a reverse-phase liquid chromatography-tandem mass spectrometry system. Degradations of paclobutrazol in both fruits followed first-order kinetics, with half-lives of about 9 days. Initial deposits were 1.63 mg/kg on peach and 1.99 mg/kg on mandarin; terminal concentrations were lower than 0.05 mg/kg, which was acceptable in most cases. As anticipated, paclobutrazol levels in peels of mature mandarin were about 6.3 times higher than in pulp, indicating the potential risk of peel consumption. We also observed that paclobutrazol degradation in mature mandarin was relatively slow, indicating it might not be efficient enough to hold mandarin fruits on trees for lowering paclobutrazol concentrations. Significant enantioselectivity was observed: the (2R,3R)-enantiomer was preferentially degraded in mandarin (whole fruit, peels, and pulp) but enriched in peach. Because of its more rapid degradation in mandarin and the lower levels observed in pulp compared with peels, potential endocrine-related side effects due to the (2R,3R)-enantiomer pose less of a risk in mandarin than in peach. PMID:24890866

  3. Computer numerical control (CNC) lithography: light-motion synchronized UV-LED lithography for 3D microfabrication

    NASA Astrophysics Data System (ADS)

    Kim, Jungkwun; Yoon, Yong-Kyu; Allen, Mark G.

    2016-03-01

    This paper presents a computer-numerical-controlled ultraviolet light-emitting diode (CNC UV-LED) lithography scheme for three-dimensional (3D) microfabrication. The CNC lithography scheme utilizes sequential multi-angled UV light exposures along with a synchronized switchable UV light source to create arbitrary 3D light traces, which are transferred into the photosensitive resist. The system comprises a switchable, movable UV-LED array as a light source, a motorized tilt-rotational sample holder, and a computer-control unit. System operation is such that the tilt-rotational sample holder moves in a pre-programmed routine, and the UV-LED is illuminated only at desired positions of the sample holder during the desired time period, enabling the formation of complex 3D microstructures. This facilitates easy fabrication of complex 3D structures, which otherwise would have required multiple manual exposure steps as in the previous multidirectional 3D UV lithography approach. Since it is batch processed, processing time is far less than that of the 3D printing approach at the expense of some reduction in the degree of achievable 3D structure complexity. In order to produce uniform light intensity from the arrayed LED light source, the UV-LED array stage has been kept rotating during exposure. UV-LED 3D fabrication capability was demonstrated through a plurality of complex structures such as V-shaped micropillars, micropanels, a micro-‘hi’ structure, a micro-‘cat’s claw,’ a micro-‘horn,’ a micro-‘calla lily,’ a micro-‘cowboy’s hat,’ and a micro-‘table napkin’ array.

  4. Photospheric and chromospheric active regions on three single-lined RS CVn binaries

    NASA Astrophysics Data System (ADS)

    Biazzo, K.; Frasca, A.; Catalano, S.; Marilli, E.

    2006-02-01

    A monitoring of three active RS CVn binaries has been performed with medium resolution spectroscopy with the aim of investigating the behavior of chromospheric and photospheric inhomogeneities. Surface temperature, as recovered from line-depth ratios (LDRs), allowed us to map the photospheric spots, while the Hα emission has been used as an indicator of chromospheric inhomogeneities. We have found that the rotational modulation of the Hα emission is always in anti-phase with the temperature wave, i.e. at the time of our observations active regions at chromospheric and photospheric levels are closely spatially associated in these active stars. The residual Hα profiles, obtained as the difference between the observed spectra and non-active templates, are well reproduced by a two Gaussian fitting. The broad emission component, responsible for the wide emission wings in near all the spectra, is often blue-shifted with respect to the center of the stellar disk. The narrow Hα emission displays a phase-dependent variation in all stars and is anti-correlated with the photospheric diagnostics, while the broad one displays no or little rotational modulation. We suggest that the broad emission component is mainly related to physical phenomena, like micro-flaring or strong chromospheric velocity fields, occurring all over the star disk, while the central narrow emission is more affected by chromospheric plages. We have also detected a modulation of the intensity of the He I D3 line with the star rotation, suggesting surface features also in the upper chromosphere of these stars.

  5. RS-Predictor models augmented with SMARTCyp reactivities: Robust metabolic regioselectivity predictions for nine CYP isozymes

    PubMed Central

    Zaretzki, Jed; Rydberg, Patrik; Bergeron, Charles; Bennett, Kristin P.; Olsen, Lars

    2012-01-01

    RS-Predictor is a tool for creating pathway-independent, isozyme-specific site of metabolism (SOM) prediction models using any set of known cytochrome P450 substrates and metabolites. Until now, the RS-Predictor method was only trained and validated on CYP 3A4 data, but in the present study we report on the versatility the RS-Predictor modeling paradigm by creating and testing regioselectivity models for substrates of the nine most important CYP isozymes. Through curation of source literature, we have assembled 680 substrates distributed among CYPs 1A2, 2A6, 2B6, 2C19, 2C8, 2C9, 2D6, 2E1 and 3A4, which we believe is the largest publicly accessible collection of P450 ligands and metabolites ever released. A comprehensive investigation into the importance of different descriptor classes for predicting the regioselectivity of each isozyme is made through the generation of multiple independent RS-Predictor models for each set of isozyme substrates. Two of these models include a DFT reactivity descriptor derived from SMARTCyp. Optimal combinations of RS-Predictor and SMARTCyp are shown to have stronger performance than either method alone, while also exceeding the accuracy of the commercial regioselectivity prediction methods distributed by StarDrop and Schrödinger, correctly identifying a large proportion of the metabolites in each substrate set within the top two rank-positions: 1A2(83.0%), 2A6(85.7%), 2B6(82.1%), 2C19(86.2%), 2C8(83.8%), 2C9(84.5%), 2D6(85.9%), 2E1(82.8%), 3A4(82.3%) and merged(86.0%). Comprehensive datamining of each substrate set and careful statistical analyses of the predictions made by the different models revealed new insights into molecular features that control metabolic regioselectivity and enable accurate prospective prediction of likely SOMs. PMID:22524152

  6. Coordinated ultraviolet and radio observations of selected nearby stars

    NASA Technical Reports Server (NTRS)

    Lang, Kenneth R.

    1987-01-01

    All of the US2 shifts assigned were successfully completed with simultaneous International Ultraviolet Explorer (IUE) and the Very Large Array (VLA) observations of the proposed target stars. The target stars included dwarf M flare stars and RS CVn stars. The combined ultraviolet (IUE) and microwave (VLA) observations have provided important new insights to the radiation mechanisms at these two widely-separated regions of the electromagnetic spectrum. The VLA results included the discovery of narrow-band microwave radiation and rapid time variations in the microwave radiation of dwarf M flare stars. The results indicate that conventional radiation mechanisms cannot explain the microwave emission from these stars. In general, ultraviolet variations and bursts occur when no similar variations are detected at microwave wavelengths and vice versa. Although these is some overlap, the variations in these two spectral regions are usually uncorrelated, suggesting that there is little interaction between the activity centers at the two associated atmospheric levels.

  7. Hypervelocity Stars

    NASA Astrophysics Data System (ADS)

    Brown, Warren R.

    2015-08-01

    Hypervelocity stars (HVSs) travel with such extreme velocities that dynamical ejection via gravitational interaction with a massive black hole (MBH) is their most likely origin. Observers have discovered dozens of unbound main-sequence stars since the first in 2005, and the velocities, stellar nature, spatial distribution, and overall numbers of unbound B stars in the Milky Way halo all fit an MBH origin. Theorists have proposed various mechanisms for ejecting unbound stars, and these mechanisms can be tested with larger and more complete samples. HVSs' properties are linked to the nature and environment of the Milky Way's MBH, and, with future proper motion measurements, their trajectories may provide unique probes of the dark matter halo that surrounds the Milky Way.

  8. Star Polygons.

    ERIC Educational Resources Information Center

    Barcham, Peter

    1990-01-01

    The author gives some insights and many examples pertaining to the teaching of properties of polygons. In particular, observations about circles leads to useful methods for drawing star-shaped polygons. (JJK)

  9. Liquid Rocket Propulsion: RS-68 and Linear Aerospike

    NASA Technical Reports Server (NTRS)

    Murphy, Terry

    1999-01-01

    This paper presents viewgraphs of the RS-68 and Linear Aerospike engines. The topics include: 1) The mission; 2) Design and Development Strategies; 3) Cost Driven Design Trades; 4) Moderate Pressure Requirements Enable Reduced Complexity; 5) Experience Based Design; 6) Development Costs Dominated by Cost of Eliminating Failure Modes; and 7) Reducing Development Costs. This paper also includes the design of the RS-68 Engine and the engine performance.

  10. Impact of DCC (rs714) and PSCA (rs2294008 and rs2976392) Gene Polymorphism in Modulating Cancer Risk in Asian Population

    PubMed Central

    Chandra, Vishal; Kim, Jong Joo; Gupta, Usha; Mittal, Balraj; Rai, Rajani

    2016-01-01

    Multiple studies have investigated the association of gene variant of Deleted in colorectal carcinoma (DCC) and Prostate Stem cell antigen (PSCA) with various cancer susceptibility; however, the results are discrepant. Since SNPs are emerging as promising biomarker of cancer susceptibility, here, we aimed to execute a meta-analysis of DCC (rs714 A > G) and PSCA (rs2294008 C > T, rs2976392 G > A) polymorphism to demonstrate the more accurate strength of these associations. We followed a rigorous inclusion/exclusion criteria and calculated the pooled odds ratios (ORs) and 95% confidence intervals (CIs). Overall, the pooled analysis showed that the DCC rs714 conferred increased risk of cancer only in Asians (AA vs. GG: OR = 1.86, p ≤ 0.0001; AG vs. GG: OR = 1.43, p = 0.005; GA + AA vs. GG: OR = 1.66, p ≤ 0.0001; AA vs. GG + GA; OR = 1.52, p ≤ 0.004, A vs. G allele: OR = 1.41, p ≤ 0.0001). PSCA rs2294008 was associated with increased overall cancer risk (TT vs. CC: OR = 1.28, p = 0.002; CT vs. CC: OR = 1.21, p ≤ 0.0001; CT + TT vs. CC: OR = 1.24, p ≤ 0.0001; TT vs. CC + CT; OR = 1.17, p ≤ 0.005, T vs. C allele: OR = 1.16, p ≤ 0.0001); however, in stratified analysis this association was limited only to gastric and bladder cancer and the strength was more prominent in Asians. In contrast, the PSCA rs2976392 SNP did not modulate the cancer risk. Therefore, we concluded that rs714 and rs2294008 polymorphism may represent a potential genetic biomarker for cancer risk in Asians and gastric as well as bladder cancer, respectively. However, since our study is limited to Asians and cancer types, further larger studies involving other cancers and/or population, gene-environment interactions and the mechanism of DCC and PSCA gene deregulation are desired to define the role of genotype with overall cancer risk. PMID:26891331

  11. (5RS,10SR,15RS)-Trimethyl­truxene1

    PubMed Central

    Thomas, Kandace R.; Dhar, Raj K.; Fronczek, Frank R.; Watkins, Steven F.

    2011-01-01

    The title mol­ecule, C30H24, was prepared as a possible precursor to buckminsterfullerene cages. The two enanti­omers adopt the anti configuration, with one S/R and two R/S methyl groups, one anti to the other two. The truxene framework is slightly non-planar: with respect to the central six-ring mean plane, the three methyl C atoms are 1.377 (3), −1.475 (3) and 1.515 (3) Å distant, whereas the respective proximate peripheral six-ring mean planes make dihedral angles of 6.27 (6), 3.45 (7) and −7.37 (7)°. PMID:22199966

  12. Association between polymorphisms of prokineticin receptor (PKR1 rs4627609 and PKR2 rs6053283) and recurrent pregnancy loss*

    PubMed Central

    Cao, Yun-lei; Zhang, Zhao-feng; Wang, Jian; Miao, Mao-hua; Xu, Jian-hua; Shen, Yue-ping; Chen, Ai-min; Du, Jing; Yuan, Wei

    2016-01-01

    Recurrent pregnancy loss (RPL) is a condition with complex etiologies, to which both genetic and environmental factors may contribute. During the last decade, studies indicated that the expression patterns of the prokineticin receptor (PKR1 and PKR2) are closely related to early pregnancy. However, there are few studies on the role of PKR1 and PKR2 in RPL. In this study, we purpose to investigate the association between polymorphisms of the prokineticin receptor (PKR1 rs4627609 and PKR2 rs6053283) and RPL on a group of 93 RPL cases and 169 healthy controls. Genotyping of the single nucleotide polymorphisms (SNPs) was performed using a Sequenom MassARRAY iPLEX system. The results revealed a significant association between PKR2 rs6053283 polymorphism and RPL (P=0.003), whereas no association was observed between PKR1 rs4627609 polymorphism and RPL (P=0.929) in the Chinese Han population. PMID:26984842

  13. IL-21 polymorphisms rs907715 and rs2221903 are associated with decreased non-small cell lung cancer susceptibility

    PubMed Central

    Liu, Lanping; Shi, Fang; Li, Shanshan; Liu, Xiuju; Wei, Lili; Zhang, Jian; Ju, Xiao; Yu, Jinming

    2015-01-01

    The etiology of lung cancer is still incompletely understood. Previous studies have suggested the association between IL-21 polymorphisms and autoimmune diseases, however, little is known about its role in lung cancer susceptibility. Here, we investigated the role of two SNPs of IL-21 gene in a cohort of non-small cell lung cancer (NSCLC) patients. A total of 128 NSCLC patients and 156 healthy controls were genotyped. Multivariate logistic regression was used to analyze the association between IL-21 polymorphisms and NSCLC risk. Our data showed that both rs907715 and rs2221903 were significantly associated with lung cancer susceptibility, and patients carrying rs907715A (P = 0.007, adjusted OR = 0.60, 95% CI = 0.42-0.87) or rs2221903G (P = 0.020, adjusted OR = 0.52, 95% CI = 0.30-0.90) allele had a decreased risk of NSCLC. Further study identified that the association between IL-21 polymorphisms and NSCLC risk was limited to lung adenocarcinoma. Haplotype analysis revealed that the AG (P = 0.006, OR = 0.072 95% CI = 0.011-0.451) and AA (P = 0.022, OR = 0.657, 95% CI = 0.458-0.941) haplotypes of rs907715/rs2221903 were associated with a decreased risk of NSCLC, whereas the GA (P = 0.0001, OR = 1.932, 95% CI = 1.378-2.710) haplotype was associated with an increased risk. In conclusion, our study demonstrates the association between IL-21 polymorphisms (rs907715 and rs2221903) and NSCLC risk in a Chinese Han population, indicating their potential role in lung cancer detection and treatment. PMID:26770592

  14. Polymorphic rs9471643 and rs6458238 upregulate PGC transcription and protein expression in overdominant or dominant models.

    PubMed

    He, Caiyun; Xu, Qian; Tu, Huakang; Sun, Liping; Gong, Yuehua; Liu, Jingwei; Yuan, Yuan

    2016-05-01

    The pepsinogen C (PGC) gene encodes a major differentiation biomarker for gastric mucosa and has two single nucleotide polymorphisms, rs9471643 G>C and rs6458238 G>A, within its 5' upstream region that are involved in gastric carcinogenesis. However, in what genetic models the two polymorphisms modulate disease risk and how they relate to gastric carcinogenesis needs further study. We fitted the most appropriate genetic models to the PGC polymorphisms and validated their robustness; then with knowledge of the genetic model, we investigated the influence of functional variant alleles or genotypes on gene expression in vitro and in vivo. We confirmed that rs9471643 CG genotype was stably associated with reduced gastric cancer risk in complete overdominant model. This favorable CG genotype was also associated with reduced atrophic gastritis risk in subjects carrying rs6458238 AG/AA genotype. The G>C transition at rs9471643 enhanced promoter activity and transcription factor binding ability, and the CG genotype was consistently associated with elevated levels of PGC mRNA, in situ protein and serum protein in complete overdominant model based-analyses. Additionally, rs6458238 AG/AA genotype was associated with reduced atrophic gastritis risk in dominant model. Its favorable A allele was related to higher promoter activity and lower transcription factor binding ability, and the AG/AA genotype showed association with elevated levels of serum PGC protein in dominant model based-analyses. Our results suggest that rs9471643 CG and rs6458238 AG/AA genotypes have important roles in up-regulating PGC expression, which may partially explain why individuals with these favorable genotypes have decreased risks of getting gastric cancer. © 2015 Wiley Periodicals, Inc. PMID:25857852

  15. IUE observation of RS CVn-like binary sigma Corona Borealis

    NASA Astrophysics Data System (ADS)

    Tarafdar, S. P.; Agrawal, P. C.

    1984-04-01

    High and low resolution IUE observations of the triple system sigma CrB are presented. The spectra show the presencee of chromospheric (O I, Si II, Mg II) and transition region lines (He II, C II, C IV) in emission. The surface fluxes of these lines are orders of magnitude higher than those observed in the sun but are comparable to their values in RS CVn binaries like UX Ari. A comparison of continuum and emission line fluxes through the small and large apertures suggests that the observed continuum and chromospheric and transition region lines are from the primary star HD 146361 which is a spectroscopic binary; the secondary, HD 146362 which is 5.3 arcsec away from the primary may be contributing a small fraction to the O I emission only. This confirms that HD 146361 is indeed an RS CVn binary and the source of X-rays from the triple system. The profiles of the h and k lines of Mg II suggest almost equal contribution from the two components of the spectroscopic binary HD 146361. This hypothesis is supported by the profiles of absorption lines. Interstellar Fe II absorptions give a value of 0.05 per cu cm for the mean interstellar hydrogen density towards sigma CrB. A hydrostatic model for the chromosphere, transition region and corona of HD 146361 has been developed and its implications have been discussed.

  16. Optical flickering of the recurrent nova RS Ophiuchi: amplitude-flux relation

    NASA Astrophysics Data System (ADS)

    Zamanov, R.; Latev, G.; Boeva, S.; Sokoloski, J. L.; Stoyanov, K.; Bachev, R.; Spassov, B.; Nikolov, G.; Golev, V.; Ibryamov, S.

    2015-07-01

    We report observations of the flickering variability of the symbiotic recurrent nova RS Oph at quiescence in five bands (UBVRI). We find evidence of a correlation between the peak-to-peak flickering amplitude (ΔF) and the average flux of the hot component (Fav). The correlation is highly significant, with a correlation coefficient of 0.85 and a p-value of ˜10-20. Combining the data from all wavebands, we find a dependence of the type Δ F ∝ F_{av}^k, with power-law index k = 1.02 ± 0.04 for the UBVRI flickering of RS Oph. Thus, the relationship between the amplitude of variability and the average flux of the hot component is consistent with linearity. The rms amplitude of flickering is on average 8 per cent (±2 per cent) of Fav. The detected correlation is similar to that found in accreting black holes/neutron stars and cataclysmic variables. The possible reasons are briefly discussed. The data are available upon request from the authors.

  17. The Effect of Xuefuzhuyu Oral Liquid on Aspirin Resistance and Its Association with rs5911, rs5787, and rs3842788 Gene Polymorphisms

    PubMed Central

    Xue, Mei; Yang, Lin; Kou, Na; Miao, Yu; Wang, Mingming; Zhao, Quanli; Ren, Junhua; Zhang, Shaoyan; Shi, Dazhuo; Chen, Keji

    2015-01-01

    Aspirin should be continued indefinitely in patients after interventional therapy, but 10% to 40% of patients experience recurrent vascular events despite adequate aspirin therapy, a condition known as aspirin resistance (AR). Xuefuzhuyu oral liquid, derived from the classic recipe Xuefuzhuyu decoction, has been well documented to inhibit platelet aggregation and to improve hemorheology. The aims of this study were to investigate the effects of Xuefuzhuyu oral liquid on AR in patients with chronic stable angina after percutaneous coronary intervention (PCI) and the possible genetic markers related to the drug response. 43 patients diagnosed as having aspirin resistance or semi-resistance were randomly divided into control and treatment groups after screening 207 stable CHD patients. Platelet aggregation rate was determined using turbidimetry. Three single nucleotide polymorphisms in COX-1 (rs5787, rs3842788) and GP IIb (rs5911) were genotyped in whole blood samples using ABI PRISM 7900 HT Fast Real-Time instrument and ABI PRISM 3730 DNA Sequencer. The results showed that Xuefuzhuyu oral liquid could effectively improve blood stasis syndrome and AR by inhibiting ADP-induced platelet aggregation and that patients with the rs5911 genetic variant exhibited better drug response upon treatment with Xuefuzhuyu oral liquid, which suggests Xuefuzhuyu oral liquid as a new possible drug for the prevention of AR. PMID:26495016

  18. Stellar surface phenomena - Asymmetric light curves of the RS Canum Venaticorum binaries lambda Andromedae and II Pegasi

    NASA Astrophysics Data System (ADS)

    Bopp, B. W.; Noah, P. V.

    1980-10-01

    The feasibility of applying the star-spot model to explain the unusual asymmetric light curves exhibited by the noneclipsing RS CVn-like binaries lambda And and II Peg is examined. A simple spot model incorporating two cool dark regions separated by 40-100 degrees in longitude and with size ratio approximately 2 to 1 can reproduce the observed light variations to a precision of approximately 0.01 m. For lambda And, two-color photometry obtained by Guinan shows a markedly different amplitude in the ultraviolet compared with the red, and permits us to establish a temperature difference delta T between photosphere and spot of approximately 800 K.

  19. Structural characterization, phase transition and dielectric properties of 4-cyanopyridynium perchlorate monohydrate: [(4-CNC 5H 4NH)][ClO 4]·H 2O

    NASA Astrophysics Data System (ADS)

    Czupiński, O.; Wojtaś, M.; Pietraszko, A.; Jakubas, R.

    2007-01-01

    Crystal structure of 4-cyanopyridynium perchlorate monohydrate ([(4-CNC 5H 4NH)][ClO 4]·H 2O) has been determined at 293 and 240 K as orthorhombic space group, Pnma and monoclinic space group, P2 1/ c, respectively, by means of single crystal X-ray diffraction. At room temperature the perchlorate anion reveals significant disorder, which is realized by the splitting of two oxygen atoms into four sites. DSC, dilatometric and dielectric spectroscopy techniques show that the crystal undergoes phase transition at 286/288 K (on cooling/heating scans). [(4-CNC 5H 4NH)][ClO 4]·H 2O appears to be an insulator with relatively high activation energy of the order of 100 kJ/mol. The phase transition in the title crystal is believed to be related to the dynamics of the perchlorate anion.

  20. Unified error model based spatial error compensation for four types of CNC machining center: Part II-unified model based spatial error compensation

    NASA Astrophysics Data System (ADS)

    Fan, Kaiguo; Yang, Jianguo; Yang, Liyan

    2014-12-01

    In this paper, a spatial error compensation method was proposed for CNC machining center based on the unified error model. The spatial error distribution was analyzed in this research. The result shows that the spatial error is relative to each axis of a CNC machine tool. Moreover, the spatial error distribution is non-linear and there is no regularity. In order to improve the modeling accuracy and efficiency, an automatic error modeling application was designed based on the orthogonal polynomials. To realize the spatial error compensation, a multi-thread parallel processing mode based error compensation controller was designed. Using the spatial error compensation method, the machine tools' accuracy is greatly improved compared to that with no compensation.

  1. The optical counterpart of the X-ray source H0253+193 - A distant, high-luminosity RS Canum Venaticorum system

    NASA Technical Reports Server (NTRS)

    Clemens, Dan P.; Leah, Robert W.

    1989-01-01

    Optical and near-infrared photometry in the VRIJHK and CO (2.35 microns) bands and optical spectroscopy and polarimetry reveal that the optical counterpart of the X-ray source H0253+193 is most likely a RS CVn binary system. The results show a visual extinction of 11.3 mag to the star, with an IR excess possibly due a cooler binary companion or circumstellar material. It is suggested that the I-band polarization of 8.1 + or - 1.8 may be induced in the starlight by passage through the molecular cloud. The lack of strong H-alpha emission in the optical spectrum argues against the possibility of a classical T Tauri star, and the IR excess argues against a naked T Tauri star. The wide energy spectrum found in the dereddened optical and near-infrared photometry supports the binary star model.

  2. Chameleon stars

    SciTech Connect

    Dzhunushaliev, Vladimir; Folomeev, Vladimir; Singleton, Douglas

    2011-10-15

    We consider a gravitating spherically symmetric configuration consisting of a scalar field nonminimally coupled to ordinary matter in the form of a perfect fluid. For this system we find static, regular, asymptotically flat solutions for both relativistic and nonrelativistic cases. It is shown that the presence of the nonminimal interaction leads to substantial changes both in the radial matter distribution of the star and in the star's total mass. A simple stability test indicates that, for the choice of parameters used in the paper, the solutions are unstable.

  3. OPMILL - MICRO COMPUTER PROGRAMMING ENVIRONMENT FOR CNC MILLING MACHINES THREE AXIS EQUATION PLOTTING CAPABILITIES

    NASA Technical Reports Server (NTRS)

    Ray, R. B.

    1994-01-01

    OPMILL is a computer operating system for a Kearney and Trecker milling machine that provides a fast and easy way to program machine part manufacture with an IBM compatible PC. The program gives the machinist an "equation plotter" feature which plots any set of equations that define axis moves (up to three axes simultaneously) and converts those equations to a machine milling program that will move a cutter along a defined path. Other supported functions include: drill with peck, bolt circle, tap, mill arc, quarter circle, circle, circle 2 pass, frame, frame 2 pass, rotary frame, pocket, loop and repeat, and copy blocks. The system includes a tool manager that can handle up to 25 tools and automatically adjusts tool length for each tool. It will display all tool information and stop the milling machine at the appropriate time. Information for the program is entered via a series of menus and compiled to the Kearney and Trecker format. The program can then be loaded into the milling machine, the tool path graphically displayed, and tool change information or the program in Kearney and Trecker format viewed. The program has a complete file handling utility that allows the user to load the program into memory from the hard disk, save the program to the disk with comments, view directories, merge a program on the disk with one in memory, save a portion of a program in memory, and change directories. OPMILL was developed on an IBM PS/2 running DOS 3.3 with 1 MB of RAM. OPMILL was written for an IBM PC or compatible 8088 or 80286 machine connected via an RS-232 port to a Kearney and Trecker Data Mill 700/C Control milling machine. It requires a "D:" drive (fixed-disk or virtual), a browse or text display utility, and an EGA or better display. Users wishing to modify and recompile the source code will also need Turbo BASIC, Turbo C, and Crescent Software's QuickPak for Turbo BASIC. IBM PC and IBM PS/2 are registered trademarks of International Business Machines. Turbo BASIC and Turbo C are trademarks of Borland International.

  4. Lipoprotein Lipase SNPs rs13702 and rs301 Correlate with Clinical Outcome in Chronic Lymphocytic Leukemia Patients

    PubMed Central

    Rombout, Ans; Stamatopoulos, Basile; Lagneaux, Laurence; Lust, Sofie; Offner, Fritz; Naessens, Evelien; Vanderstraeten, Hanne; Verhasselt, Bruno; Philippé, Jan

    2015-01-01

    Chronic lymphocytic leukemia (CLL) is the most common leukemia in the Western world and is characterized by a heterogeneous clinical course. This variability in clinical course has spiked the search for prognostic markers able to predict patient evolution at the moment of diagnosis. Markers demonstrated to be of value are the mutation status of the immunoglobulin heavy chain variable region genes (IGHV) and lipoprotein lipase (LPL) expression. High LPL mRNA expression has been associated with short treatment free (TFS) and decreased overall survival (OS) in CLL. The LPL SNPs rs301 (Trs328 (Crs13702 (Trs13702 wild-type T/T genotype had significantly shorter OS than patients with C/C and T/C genotypes (median time until CLL related death: 90 and 156 months respectively, p=0.008). The same was observed for LPL SNP rs301 (median time until CLL related death T/T: 102 and C/C, T/C: 144 months, p=0.03). Both SNPs rs301 and rs13702 were significantly associated with each other and notably, no association was found between IGHV status and presence of the SNP genotypes, indicating that these LPL SNPs are reliable prognostic markers that could add extra prognostic and predictive information to classical markers and help to improve the management of CLL. PMID:25811490

  5. Lipoprotein lipase SNPs rs13702 and rs301 correlate with clinical outcome in chronic lymphocytic leukemia patients.

    PubMed

    Rombout, Ans; Stamatopoulos, Basile; Lagneaux, Laurence; Lust, Sofie; Offner, Fritz; Naessens, Evelien; Vanderstraeten, Hanne; Verhasselt, Bruno; Philippé, Jan

    2015-01-01

    Chronic lymphocytic leukemia (CLL) is the most common leukemia in the Western world and is characterized by a heterogeneous clinical course. This variability in clinical course has spiked the search for prognostic markers able to predict patient evolution at the moment of diagnosis. Markers demonstrated to be of value are the mutation status of the immunoglobulin heavy chain variable region genes (IGHV) and lipoprotein lipase (LPL) expression. High LPL mRNA expression has been associated with short treatment free (TFS) and decreased overall survival (OS) in CLL. The LPL SNPs rs301 (Trs328 (Crs13702 (Trs13702 wild-type T/T genotype had significantly shorter OS than patients with C/C and T/C genotypes (median time until CLL related death: 90 and 156 months respectively, p=0.008). The same was observed for LPL SNP rs301 (median time until CLL related death T/T: 102 and C/C, T/C: 144 months, p=0.03). Both SNPs rs301 and rs13702 were significantly associated with each other and notably, no association was found between IGHV status and presence of the SNP genotypes, indicating that these LPL SNPs are reliable prognostic markers that could add extra prognostic and predictive information to classical markers and help to improve the management of CLL. PMID:25811490

  6. The friendly stars

    NASA Astrophysics Data System (ADS)

    Martin, Martha Evans

    Describes prominent stars such as Vega, Arcturus, and Antares and means of identifying them, discusses the constellations in which they are located, and explains star names, stellar light, distances between stars, and types of stars.

  7. Chromospheres and coronae of late-type stars

    NASA Technical Reports Server (NTRS)

    Dupree, A. K.; Black, J. H.; Davis, R.; Hartmann, L.; Raymond, J. C.

    1979-01-01

    IUE short wavelength (1150-2000 A) spectra of late-type dwarfs, giant, and supergiant stars show a variety of emission features varying in excitation from about 10,000 K to about 3 x 10 to the 5th K. High excitation species are found most strongly in main sequence stars. Dwarf stars with active chromospheres (e.g., Xi Boo) and flare stars (EQ Peg) show enhancement of surface flux as compared to the quiet sun; binary systems of W UMa and RS CVn types show even larger surface fluxes. The enhancement increases with temperature of formation much like a solar active region. The presence of high excitation species in the giant and supergiant stars suggests that parameters other than effective temperature and luminosity are important in establishing a transition region and corona.

  8. Einstein Observatory coronal temperatures of late-type stars

    NASA Technical Reports Server (NTRS)

    Schmitt, J. H. M. M.; Collura, A.; Sciortino, S.; Vaiana, G. S.; Harnden, F. R., Jr.

    1990-01-01

    The results are presented of a survey of the coronal temperatures of late-type stars using the Einstein Observatory IPC. The spectral analysis shows that the frequently found one- and two-temperature descriptions are mainly influenced by the SNR of the data and that models using continuous emission measure distributions can provide equally adequate and physically more meaningful and more plausible descriptions. Intrinsic differences in differential emission measure distributions are found for four groups of stars. M dwarfs generally show evidence for high-temperature gas in conjunction with lower-temperature material, while main-sequence stars of types F and G have the high-temperature component either absent or very weak. Very hot coronae without the lower-temperature component appearing in dwarf stars are evident in most of the giant stars studied. RS CVn systems show evidence for extremely hot coronae, sometimes with no accompanying lower-temperature material.

  9. Star Power

    SciTech Connect

    2014-10-17

    The U.S. Department of Energy's Princeton Plasma Physics Laboratory has released ''Star Power,'' a new informational video that uses dramatic and beautiful images and thought-provoking interviews to highlight the importance of the Laboratory's research into magnetic fusion.

  10. Star quality.

    PubMed

    Dent, Emma

    2007-09-20

    Around 150 wards are participating in the voluntary Star Wards scheme to provide mental health inpatients with more activities with therapeutic value. Suggested activities range from a library, to horse riding Internet access and comedy. Service users are particularly keen to have more exercise, which can be a challenge in inpatient settings. PMID:17970387

  11. Star Power

    ScienceCinema

    None

    2014-11-18

    The U.S. Department of Energy's Princeton Plasma Physics Laboratory has released ''Star Power,'' a new informational video that uses dramatic and beautiful images and thought-provoking interviews to highlight the importance of the Laboratory's research into magnetic fusion.

  12. Brittle Star

    USGS Multimedia Gallery

    A tiny brittle star (the central disc is smaller than a dime) clings to the branches of a soft coral in a sample bucket brought into the shipboard laboratory from a submersible dive. This creature makes its home on the deep, dark ocean floor. ...

  13. Polymorphisms rs12998 and rs5780218 in KiSS1 Suppressor Metastasis Gene in Mexican Patients with Breast Cancer

    PubMed Central

    Cruz Quevedo, Edhit Guadalupe; Mimendi Aguilar, Gabriela Monserrat; Juárez Aguilar, Luis Anselmo; Gutierrez Rubio, Susan Andrea; Flores Martínez, Silvia Esperanza; Dávalos Rodríguez, Ingrid Patricia; Sánchez Corona, José; Torres Morán, Martha Isabel; Rosales Gómez, Roberto Carlos; Morán Moguel, María Cristina

    2015-01-01

    Aims. KiSS1 is a metastasis suppressor gene associated with inhibition of cellular chemotaxis and invasion attenuating the metastasis in melanoma and breast cancer cell lines. Along the KiSS-1 gene at least 294 SNPs have been described; however the association of these polymorphisms as genetic markers for metastasis in breast cancer studies has not been investigated. Here we describe two simple PCR-RFLPs protocols to identify the rs5780218 (9DelT) and the rs12998 (E20K) KiSS1 polymorphisms and the allelic, genotypic, and haplotypic frequencies in Mexican general population (GP) and patients with benign breast disease (BBD) or breast cancer (BC). Results. The rs5780218 polymorphism was individually associated with breast cancer (P = 0.0332) and the rs12998 polymorphism shows statistically significant differences when GP versus case (BC and BBD) groups were compared (P < 0.0001). The H1 Haplotype (G/-) occurred more frequently in BC group (0.4256) whereas H2 haplotype (G/T) was the most prevalent in BBD group (0.4674). Conclusions. Our data indicated that the rs5780218 polymorphism individually confers susceptibility for development of breast cancer in Mexican population and a possible role as a genetic marker in breast cancer metastasis for H1 haplotype (Wt/variant) in KiSS1 gene must be analyzed in other populations. PMID:25810563

  14. RS 30026: a potent and effective calcium channel agonist.

    PubMed Central

    Patmore, L.; Duncan, G. P.; Clarke, B.; Anderson, A. J.; Greenhouse, R.; Pfister, J. R.

    1990-01-01

    1. A series of dihydropyridine derivatives has been evaluated for calcium channel agonist activity using reversal of nisoldipine-induced inhibition of beating of aggregates of embryonic chick myocytes. This test appears to be specific for calcium channel agonists since isoprenaline and cardiac glycosides are inactive. 2. RS 30026 was the most potent of the series, was significantly more potent than CGP 28392 and of similar potency to Bay K 8644 (pEC50 = 7.45, 6.16 and 7.20, respectively). RS 30026 increased edge movement of individual aggregates, in the absence of nisoldipine, by 50% at 2 nM. 3. Compounds were also evaluated for their effects on guinea-pig papillary muscle and porcine coronary artery rings. RS 30026 displayed positive inotropism at concentrations between 10(-9) and 10(-6) M (pEC200 = 8.21), but was a much more powerful inotrope than Bay K 8644, increasing contractility to 1300% of control at 10(-6) M (compared to 350% of control for Bay K 8644). RS 30026 caused vasoconstriction at concentrations between 10(-10) and 10(-7) M. 4. Calcium channel currents in single embryonic chick myocytes were recorded by whole-cell voltage clamp techniques. RS 30026 (100 nM-500 nM) produced large increases in peak current amplitude and shifted the voltage for threshold and maximal currents to more negative values. RS 30026 (500 nM) also produced large increases in the inward tail currents evoked upon repolarization. The effects of Bay K 8644 (50 and 500 nM) were much less marked.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1694461

  15. Intermittent process measurement and process capability analysis using MP700 touch trigger probe on a CNC machining center

    NASA Astrophysics Data System (ADS)

    Shiou, Fang-Jung; Su, Po-Chuan

    2006-11-01

    This study developed an intermittent process measurement system by integrating a MP700 touch trigger probe system with a machining center to measure a workpiece containing freeform surface and regular geometric features, and to do the statistical process control analysis. The whole measuring system, consisting of a personal computer, a CNC machining center controller, a RENISHAW MP700 touch probe system, was integrated information-technically. Measuring software was also developed to simulate the measuring path, to prevent collision, to generate the corresponding measuring NC codes and to calculate the process capability indices, such as the process capability index (Cp), the process performance index (C PK) and the accuracy capability index (Ca). To evaluate the performance of the developed measuring system, a carrier combined with a freeform surface and regular geometric features, referred to in the ISO 10791-7 cutting test standard, was designed. Six pieces of the tested carriers were manufactured and inspected using the MP700 touch trigger probe to evaluate the performance of the developed measuring system. According to the measuring results, the developed measuring system was successfully and effectively used to carry out the intermittent process measurement and the statistical process analysis of the measuring results of some test carriers on the machining center.

  16. Use of a turbulent mixing CNC to study the influence of composition and vapor properties on heterogenous nucleation

    NASA Astrophysics Data System (ADS)

    Hopke, Philip K.; Lee, D. W.; Mavliev, Rashid; Wang, Hwa-Chi

    2000-08-01

    A new method for changing the supersaturation in the Turbulent Mixing CNC has been developed and used to study the influence of composition and vapor properties on heterogeneous nucleation. Supersaturation was controlled by changing the condensing vapor pressure in nozzle flow by saturating only a predetermined part of the flow while the total flow and temperature remain constant. This approach allows changing the initial vapor pressure while keeping the flow structure and temperature field unchanged. Experimental results for transitions from heterogeneous nucleation to homogeneous nucleation are presented for NaCl and WOx particles at various DBP vapor pressures. With increasing of the DBP vapor pressure, the concentration of enlarged particles increases until it reaches a plateau. At higher initial values of DBP pressure, homogeneous nucleation prevails and the number concentration of particles follows a curve typical for homogeneous nucleation recorded in the absence of nuclei. Nuclei with different mobility diameters were activated at different values of vapor pressure. There are significant differences in the slopes of particle activation curves for NaCl and WOx particles. The reasons for such differences are the subject for continuing research.

  17. Flank wears Simulation by using back propagation neural network when cutting hardened H-13 steel in CNC End Milling

    NASA Astrophysics Data System (ADS)

    Hazza, Muataz Hazza F. Al; Adesta, Erry Y. T.; Riza, Muhammad

    2013-12-01

    High speed milling has many advantages such as higher removal rate and high productivity. However, higher cutting speed increase the flank wear rate and thus reducing the cutting tool life. Therefore estimating and predicting the flank wear length in early stages reduces the risk of unaccepted tooling cost. This research presents a neural network model for predicting and simulating the flank wear in the CNC end milling process. A set of sparse experimental data for finish end milling on AISI H13 at hardness of 48 HRC have been conducted to measure the flank wear length. Then the measured data have been used to train the developed neural network model. Artificial neural network (ANN) was applied to predict the flank wear length. The neural network contains twenty hidden layer with feed forward back propagation hierarchical. The neural network has been designed with MATLAB Neural Network Toolbox. The results show a high correlation between the predicted and the observed flank wear which indicates the validity of the models.

  18. Restoring New Agegraphic Dark Energy in RS II Braneworld

    NASA Astrophysics Data System (ADS)

    Jamil, Mubasher; Karami, K.; Sheykhi, A.

    2011-10-01

    Motivated by recent works (Saridakis in Phys. Lett. B 660:138, 2008; Sheykhi in Int. J. Mod. Phys. D 19(3):305, 2010), we investigate the new agegraphic model of dark energy in the framework of RS II braneworld. We also include the case of variable gravitational constant G in our model. Moreover, we reconstruct the potential and the dynamics of the quintessence, tachyon, K-essence and dilaton scalar field models according to the evolutionary behavior of the new agegraphic dark energy model in RS II braneworld cosmology including varying G.

  19. MMP-9 gene polymorphisms (rs3918242, rs3918254 and rs4810482) and the risk of psoriasis vulgaris: No evidence for associations in a Chinese Han population.

    PubMed

    Liang, Jingyao; Zhao, Tian; Yang, Juan; Li, Wei; Zhang, Fang; Zhang, Sanquan; Huang, Zhenming; Lin, Rihua; Zhang, Xibao

    2015-12-01

    Several previous studies including one of them co-authored by our group have revealed that serum and psoriatic plaque expression of matrix metalloproteinase-9 (MMP-9) was significantly upregulated in psoriasis. The aim of this study was to investigate the association of three single nucleotide polymorphisms (SNPs) and haplotypes of MMP-9 (rs3918242, rs3918254 and rs4810482) with psoriasis vulgaris in a Chinese Han population. The serum levels of MMP-9 in 245 psoriasis vulgaris cases and 256 healthy controls were assessed using ELSA kits, and the three SNPs were genotyped using polymerase chain reaction-ligation detection reaction (PCR-LDR) method. Four haplotypes based on the three SNPs were also analyzed. Our study showed that the serum MMP-9 levels in patients with psoriasis vulgaris were significantly higher than that in controls (P<0.05). However, the three SNPs were not significantly associated with psoriasis vulgaris susceptibility (all P>0.05). Similar results were found in further subgroup analysis based on gender, age of onset, family history, and serum MMP-9 levels, except that a protective effect of psoriasis vulgaris was detected among female subjects with the CT genotype of rs3918254 (OR=0.47, 95% CI=0.23-0.96, P=0.038), but this association did not survive after Bonferroni correction (Padj=0.076). The haplotype analysis also failed to show any association with psoriasis vulgaris. We found no evidence for the association between the MMP-9 polymorphisms and psoriasis vulgaris susceptibility in a Chinese Han population. PMID:26554609

  20. Association of Versican (VCAN) gene polymorphisms rs251124 and rs2287926 (G428D), with intracranial aneurysm.

    PubMed

    Sathyan, Sanish; Koshy, Linda V; Balan, Shabeesh; Easwer, H V; Premkumar, S; Nair, Suresh; Bhattacharya, R N; Alapatt, Jacob P; Banerjee, Moinak

    2014-12-01

    Intracranial aneurysm (IA) accounts for 85% of Subarachnoid Hemorrhage (SAH) and is mainly caused due to the weakening of arterial wall. The structural integrity of the intracranial arteries is mainly influenced by the extracellular matrix (ECM) remodeling. The Proteoglycan Versican plays an important role in extracellular matrix assembly and plays a major role in the pathogenesis of IA. The linkage studies also indicated VCAN as a putative candidate gene for IA in the 5q22-31 region. Using a case-control study design, we tested the hypothesis whether the variants in VCAN gene, nonsynonymous variants in the coding region of Glycosaminoglycan α (GAG-α) and GAG-β and two reported SNPs involved in splicing rs251124 and rs173686 can increase the risk of aSAH among South Indian patients, either independently, or by interacting with other risk factors of the disease. We selected 200 radiologically confirmed aneurysmal cases and 250 ethnically, age and sex matched controls from the Dravidian Malayalam speaking population of South India. The present study reiterated the earlier association of rs251124 with intracranial aneurysm (P = 0.0002) and also found a novel association with rs2287926 (G428D) in exon 7 coding for GAG-α with intracranial aneurysm (P = 0.0015). Interestingly, both these SNPs contributed to higher risk for aneurysm in males. In-silico analysis predicted this SNP to have the highest functional relevance in the gene which might have a potentially altered regulatory role in transcription and splicing. Using meta-analysis with available literature rs251124 was found to be the strongest intracranial aneurysm marker for global ethnicities. This study with a novel functional SNP rs2287926 (G428D) further substantiates the potential role of VCAN in the pathogenesis of IA. PMID:25606449

  1. Association of Versican (VCAN) gene polymorphisms rs251124 and rs2287926 (G428D), with intracranial aneurysm

    PubMed Central

    Sathyan, Sanish; Koshy, Linda V.; Balan, Shabeesh; Easwer, H.V.; Premkumar, S.; Nair, Suresh; Bhattacharya, R.N.; Alapatt, Jacob P.; Banerjee, Moinak

    2014-01-01

    Intracranial aneurysm (IA) accounts for 85% of Subarachnoid Hemorrhage (SAH) and is mainly caused due to the weakening of arterial wall. The structural integrity of the intracranial arteries is mainly influenced by the extracellular matrix (ECM) remodeling. The Proteoglycan Versican plays an important role in extracellular matrix assembly and plays a major role in the pathogenesis of IA. The linkage studies also indicated VCAN as a putative candidate gene for IA in the 5q22–31 region. Using a case–control study design, we tested the hypothesis whether the variants in VCAN gene, nonsynonymous variants in the coding region of Glycosaminoglycan α (GAG-α) and GAG-β and two reported SNPs involved in splicing rs251124 and rs173686 can increase the risk of aSAH among South Indian patients, either independently, or by interacting with other risk factors of the disease. We selected 200 radiologically confirmed aneurysmal cases and 250 ethnically, age and sex matched controls from the Dravidian Malayalam speaking population of South India. The present study reiterated the earlier association of rs251124 with intracranial aneurysm (P = 0.0002) and also found a novel association with rs2287926 (G428D) in exon 7 coding for GAG-α with intracranial aneurysm (P = 0.0015). Interestingly, both these SNPs contributed to higher risk for aneurysm in males. In-silico analysis predicted this SNP to have the highest functional relevance in the gene which might have a potentially altered regulatory role in transcription and splicing. Using meta-analysis with available literature rs251124 was found to be the strongest intracranial aneurysm marker for global ethnicities. This study with a novel functional SNP rs2287926 (G428D) further substantiates the potential role of VCAN in the pathogenesis of IA. PMID:25606449

  2. Association between TNF-α rs1799724 and rs1800629 polymorphisms and the risk of Crohn's disease.

    PubMed

    Mao, Y Q; Dong, S Q; Gao, M

    2015-01-01

    We investigated the associations between 2 major tumor necrosis factor-α (TNF-α) polymorphisms, rs1799724 C>T and rs1800629 G>A, and the susceptibility to Crohn's disease (CD) using a meta-analysis framework. The PubMed, EBSCO, Ovid, Wiley, Web of Science, WANFANG, and VIP databases (last updated search in October 2014) were comprehensively searched for relevant published studies. The studies retrieved from database searches were filtered based on inclusion and exclusion criteria, and the resultant data extracted from the selected studies were analyzed using the Comprehensive Meta-analysis 2.0 software. Eleven case-control studies, containing 2000 CD patients and 3499 healthy controls, were identified as relevant to this meta-analysis. Data extracted from these 11 studies were analyzed to understand the role of the 2 TNF-α polymorphisms in CD. We found that the TNF-α rs1799724 C>T polymorphism increased the susceptibility to CD (allele model: OR = 1.293, 95%CI = 1.090-1.534, P = 0.003; dominant model: OR = 1.258, 95%CI = 1.031-1.534, P = 0.024). In contrast, we found no significant association between the TNF-α rs1800629 G>A polymorphism and CD susceptibility (allele model: OR = 1.005, 95%CI = 0.864-1.170, P = 0.945; dominant model: OR = 0.962, 95%CI = 0.809-1.145, P = 0.667). This meta-analysis showed that the TNF-α rs1799724 C>T polymorphism is associated with CD susceptibility, while the TNF-α rs1800629 G>A polymorphism appeared to have no correlation with the susceptibility to CD. PMID:26634549

  3. Microwave observations of late-type stars with the Very Large Array

    NASA Technical Reports Server (NTRS)

    Pallavicini, R.; Willson, R. F.; Lang, K. R.

    1985-01-01

    The Very Large Array was used to search for microwave emission from 32 stars of late spectral type including RS CVn type stars, dwarf M stars, and stars with active chromospheres, coronae, or intense magnetic fields. The RS CVn stars were detected at 6 cm wavelength, and upper limits are established for another six. Radio emission was detected from three dwarf M flare stars, UV Cet, EQ Peg and YZ CMi. Both impulsive (no more than 20 s) and more gradual (at least ten minutes) bursts were observed from the flare star YZ CMi. Radio emission was not confirmed at 6 cm from the solar type star Chi(1) Ori, with an upper limit that is three times lower than the detections reported by other observers. Microwave emission could not be detected from any other solar type star of spectral class F to K. The quiescent radio emission from dwarf M flare stars was interpreted as nonthermal gyrosynchrotron emission by mildly relativistic electrons accelerated more or less continuously in the magnetic fields of starspots.

  4. AngiomiRs: Potential Biomarkers of Pregnancy's Vascular Pathologies

    PubMed Central

    Rodríguez Santa, Laura María; González Teshima, Laura Yuriko; Forero Forero, Jose Vicente; Castillo Giraldo, Andres Orlando

    2015-01-01

    In recent years, microRNAs (miRNAs) have been the focus of research for their role in posttranscriptional regulation and as potential biomarkers of risk for disease development. Their identification in specific physiological processes, like angiogenesis, a key pathway in placental vascular development in pregnancy, suggests an important role of miRNAs that regulate angiogenesis (angiomiRs). Many complications of pregnancy have in common placental vascular alterations, involving an imbalance in the angiogenesis process in the development of conditions such as preeclampsia, intrauterine growth restriction, and gestational diabetes, complications with the highest rates of morbimortality in pregnancy. Many studies have identified angiomiRs with differential expression profiles in each of these diseases; however, this evidence requires further studies focused on evaluating their potential as biomarkers of risk for the angiomiRs detected, to establish correlations between placental tissue and serum/plasma expression profiles. Therefore, the objective of this review is to highlight the best angiomiRs detected in placental tissue and serum/plasma in each of these three pathologies to show the current data available for potential biomarkers and to propose future research strategies on this topic. PMID:26550492

  5. rsPSCs: A new type of pluripotent stem cells.

    PubMed

    Weissbein, Uri; Benvenisty, Nissim

    2015-08-01

    Pluripotent stem cells capture the imagination since they can differentiate into all cell types in our body. Recent evidence suggests that in addition to embryonic stem cells (ESCs) and epiblast stem cells (EpiSCs), a new type of region-selective pluripotent stem cells (rsPSCs) exists, possessing unique spatial and molecular characteristics. PMID:26077383

  6. Work in Progress: The Seven Rs of Team Building

    ERIC Educational Resources Information Center

    Brunelli, Jean; Schneider, Elaine Fogel

    2004-01-01

    This article argues that supportive teams--including professionals, paraprofessionals, and parents--can teach staff members how to identify and implement best practices in early intervention settings. The authors describe "the seven Rs of team building" distilled from their many years of team building and maintenance: 1) Reading cues; 2) Regular…

  7. Christmas star.

    NASA Astrophysics Data System (ADS)

    Biała, J.

    There are continuous attempts to identify the legendary Christmas Star with a real astronomical event accompanying the birth of Jesus from Nazareth. Unfortunately, the date of birth is difficult to establish on the basis of historical records with better accuracy than a few years. During that period a number of peculiar astronomical events were observed and it seem to be impossible to identify the right one unambiguously.

  8. Neutron Stars

    NASA Astrophysics Data System (ADS)

    van den Heuvel, Ed

    Radio pulsars are unique laboratories for a wide range of physics and astrophysics. Understanding how they are created, how they evolve and where we find them in the Galaxy, with or without binary companions, is highly constraining of theories of stellar and binary evolution. Pulsars' relationship with a recently discovered variety of apparently different classes of neutron stars is an interesting modern astrophysical puzzle which we consider in Part I of this review. Radio pulsars are also famous for allowing us to probe the laws of nature at a fundamental level. They act as precise cosmic clocks and, when in a binary system with a companion star, provide indispensable venues for precision tests of gravity. The different applications of radio pulsars for fundamental physics will be discussed in Part II. We finish by making mention of the newly discovered class of astrophysical objects, the Fast Radio Bursts, which may or may not be related to radio pulsars or neutron stars, but which were discovered in observations of the latter.

  9. Symbiotic Stars

    NASA Astrophysics Data System (ADS)

    Munari, U.

    2012-06-01

    Symbiotic stars are interacting binary systems composed of a white dwarf (WD) accreting at high rate from a cool giant companion, which frequently fills its Roche lobe. The WD usually is extremely hot and luminous, and able to ionize a sizeable fraction of the cool giant wind, because it is believed the WD undergoes stable hydrogen nuclear burning on its surface of the material accreted from the companion. This leads to consider symbiotic stars as good candidates for the yet-to-be-identified progenitors of type Ia supernovae. Symbiotic stars display the simultaneous presence of many different types of variability, induced by the cool giant, the accreting WD, the circumstellar dust and ionized gas, with time scales ranging from seconds to decades. The long orbital periods (typically a couple of years) and complex outburst patterns, lasting from a few years to a century, make observations from professionals almost impossible to carry out, and open great opportunities to amateur astronomers to contribute fundamental data to science.

  10. Modulation of central noradrenergic function by RS-15385-197.

    PubMed Central

    Redfern, W. S.; MacKinnon, A. C.; Brown, C. M.; Martin, A. B.; Kilpatrick, A. T.; Clague, R. U.; Spedding, M.

    1993-01-01

    1. RS-15385-197, a highly potent and selective alpha 2-adrenoceptor antagonist, was examined in a variety of in vitro and in vivo functional tests to assess the selectivity of its interaction with central noradrenergic neurones in the rat. 2. In hypothalamic slices, RS-15385-197 was potent in augmenting K(+)-evoked release of [3H]-noradrenaline, with an EC50 of 9 nM. Idazoxan and yohimbine showed 100 fold less activity. This was due to its antagonist action at presynaptic alpha 2-adrenoceptors, as RS-15385-197 (10 microM), did not directly release [3H]-noradrenaline from cortical slices unlike reserpine (10 microM), and did not inhibit noradrenaline re-uptake into cortical synaptosomes. 3. In vivo, RS-15385-197 (0.5 mg kg-1, p.o.) increased levels of 3-methoxy-4-hydroxy-phenylglycol (MHPG) in the cerebral cortex without modifying levels of 5-hydroxyindoleacetic acid (5-HIAA). This dose, but not a lower dose (0.1 mg kg-1, p.o.) caused beta-adrenoceptor down-regulation in the cortex when administered once daily for 14 days whereas 5-HT2 receptor number was unaltered, indicating a selective effect on noradrenergic transmission. 4. Selective depletion of cortical 5-HT by administration of p-chlorophenylalanine (PCPA; 100 mg kg-1, i.p. for 14 days) or 5,7-dihydroxytryptamine (5,7-DHT; 150 micrograms i.c.v.) prevented the beta-adrenoceptor down-regulation caused by RS-15385-197, indicating that a tonic 5-hydroxytryptaminergic input was required for it to elicit beta-adrenoceptor down-regulation.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8095421

  11. Radii, masses, and ages of 18 bright stars using interferometry and new estimations of exoplanetary parameters

    NASA Astrophysics Data System (ADS)

    Ligi, R.; Creevey, O.; Mourard, D.; Crida, A.; Lagrange, A.-M.; Nardetto, N.; Perraut, K.; Schultheis, M.; Tallon-Bosc, I.; ten Brummelaar, T.

    2016-02-01

    Context. Accurate stellar parameters are needed in numerous domains of astrophysics. The position of stars on the Hertzsprung-Russell diagram is an important indication of their structure and evolution, and it helps improve stellar models. Furthermore, the age and mass of stars hosting planets are required elements for studying exoplanetary systems. Aims: We aim at determining accurate parameters of a set of 18 bright exoplanet host and potential host stars from interferometric measurements, photometry, and stellar models. Methods: Using the VEGA/CHARA interferometer operating in the visible domain, we measured the angular diameters of 18 stars, ten of which host exoplanets. We combined them with their distances to estimate their radii. We used photometry to derive their bolometric flux and, then, their effective temperature and luminosity to place them on the H-R diagram. We then used the PARSEC models to derive their best fit ages and masses, with error bars derived from Monte Carlo calculations. Results: Our interferometric measurements lead to an average of 1.9% uncertainty on angular diameters and 3% on stellar radii. There is good agreement between measured and indirect estimations of angular diameters (either from SED fitting or from surface brightness relations) for main sequence (MS) stars, but not as good for more evolved stars. For each star, we provide a likelihood map in the mass-age plane; typically, two distinct sets of solutions appear (an old and a young age). The errors on the ages and masses that we provide account for the metallicity uncertainties, which are often neglected by other works. From measurements of its radius and density, we also provide the mass of 55 Cnc independently of models. From the stellar masses, we provide new estimates of semi-major axes and minimum masses of exoplanets with reliable uncertainties. We also derive the radius, density, and mass of 55 Cnc e, a super-Earth that transits its stellar host. Our exoplanetary parameters reflect the known population of exoplanets. Conclusions: This work illustrates how precise interferometric measurements of angular diameters and detailled modeling allow fundamental parameters of exoplanet host stars to be constrained at a level permiting analysis of the planet's parameters.

  12. A Vanishing Star Revisited

    NASA Astrophysics Data System (ADS)

    1999-07-01

    VLT Observations of an Unusual Stellar System Reinhold Häfner of the Munich University Observatory (Germany) is a happy astronomer. In 1988, when he was working at a telescope at the ESO La Silla observatory, he came across a strange star that suddenly vanished off the computer screen. He had to wait for more than a decade to get the full explanation of this unusual event. On June 10-11, 1999, he observed the same star with the first VLT 8.2-m Unit Telescope (ANTU) and the FORS1 astronomical instrument at Paranal [1]. With the vast power of this new research facility, he was now able to determine the physical properties of a very strange stellar system in which two planet-size stars orbit each other. One is an exceedingly hot white dwarf star , weighing half as much as the Sun, but only twice as big as the Earth. The other is a much cooler and less massive red dwarf star , one-and-a-half times the size of planet Jupiter. Once every three hours, the hot star disappears behind the other, as seen from the Earth. For a few minutes, the brightness of the system drops by a factor of more than 250 and it "vanishes" from view in telescopes smaller than the VLT. A variable star named NN Serpentis ESO PR Photo 30a/99 ESO PR Photo 30a/99 [Preview - JPEG: 400 x 468 pix - 152k] [Normal - JPEG: 800 x 936 pix - 576k] [High-Res - JPEG: 2304 x 2695 pix - 4.4M] Caption to ESO PR Photo 30a/99 : The sky field around the 17-mag variable stellar system NN Serpentis , as seen in a 5 sec exposure through a V(isual) filter with VLT ANTU and FORS1. It was obtained just before the observation of an eclipse of this unsual object and served to centre the telescope on the corresponding sky position. The field shown here measures 4.5 x 4.5 armin 2 (1365 x 1365 pix 2 ; 0.20 arcsec/pix). The field is somewhat larger than that shown in Photo 30b/99 and has the same orientation to allow comparison: North is about 20° anticlockwise from the top and East is 90° clockwise from that direction. The unsual star in question is designated NN Serpentis , or just NN Ser . As the name indicates, it is located in the constellation of Serpens (The Serpent), about 12° north of the celestial equator. A double letter, here "NN", is used to denote variable stars [2]. It is a rather faint object of magnitude 17, about 25,000 times fainter than what can be perceived with the unaided eye. The distance is about 600 light-years (180 pc). In July 1988, Reinhold Häfner performed observations of NN Ser (at that time still known by its earlier name PG 1550+131 ) with the Danish 1.54-m telescope at La Silla. He was surprised, but also very pleased to discover that it underwent a very deep eclipse every 187 minutes. Within less than 2 minutes, the brightness dropped by a factor of more than 100 (5 magnitudes). During the next 9 minutes, the star completely disappeared from view - it was too faint to be observed with this telescope. It then again reappeared and the entire event was over after just 11 minutes. Why eclipses are so important for stellar studies An eclipse occurs when one of the stars in a binary stellar system moves in front of the other, as seen by the observer. The effect is similar to what happens during a solar eclipse when the Moon moves in front of the Sun. In both cases, the eclipse may be partial or total , depending on whether or not the eclipsed star (or the Sun) is completely hidden from view. The occurence of eclipses in stellar systems, as seen from the Earth, depends on the spatial orientation of the orbital plane and the sizes of the two stars. Two eclipses take place during one orbital revolution, but they may not both be observable. The physical properties of the two stars in a binary system (e.g., the sizes of the stars, the size and shape of the orbit, the distribution of the light on the surfaces of the stars, their temperatures etc.) can be determined from the measured "light-curve" of the system (a plot of brightness vrs. time). The stars are always too close to each other to be seen as anything but a point of light. The light-curve thus describes the way the total brightness of the two stars changes during one orbital revolution, including the variation of the combined light of the two components as they cover each other during the eclipses. Already in 1988, it was concluded that the eclipse observed in NN Ser must be caused by a bright and hot star (a white dwarf ) being hidden by another body, most probably a red dwarf star . Because of the dramatic effect, this object soon became known as the "Vanishing Star" , cf. ESO Press Release 09/88 (8 December 1988). Critical information missing for NN Ser One particularly critical piece of information is needed for a light-curve study to succeed, that is whether the eclipse is "total" or "partial" . If during the eclipse one star is entirely hidden by the other, we only see the light of the star in front. In that case, the measured amount of light does not change during the phase of totality. The light-curve is "flat" at the bottom of the minimum and the measured brightness indicates the intrinsic luminosity of the eclipsing star. Moreover, for a given orbit, the duration of the totality is proportional to the size of that star. This crucial information was not available for NN Ser . The brightness at minimum was simply too faint to allow any measurements of the system with available telescopes during this phase. For this reason, the properties of the eclipsing star could only be guessed. Reaching for the bottom The new VLT observations have overcome this. Thanks to the powerful combination of the 8.2-m ANTU telescope and the multi-mode FORS1 instrument, it was possible to measure the complete lightcurve of NN Ser , also during the darkest phase of the eclipse. This extreme observation demanded most careful preparation. Since there is very little light available, the longest possible integration time must be used in order to collect a sufficient number of photons and to achieve a reasonable photometric accuracy. However, the eclipse only lasts a few minutes and it would only be possible to exposure and read-out a few, normal exposures from the CCD camera, not enough to fully characterize the light curve at minimum. Reinhold Häfner decided to use another method. By having the telescope perform a controlled change of position on the sky ("drift") during the exposure, the light from NN Ser before, during and after the eclipse will not be registered on the same spot of the camera detector, but rather along a line. He carefully chose a direction in which this line would not cross those of other stars in the neighbourhood of NN Ser . This was ensured by rotating FORS1 to a predetermined position angle. The drift rate was fixed as one pixel (0.20 arcsec) per 3 seconds of time, a compromise between the necessary integration time and desired time resolution that would give the best chance to document the exact shape of the light-curve . In theory, this would then allow the measurement of the intensity along the recorded trail of NN Ser and hence its brightness at any given time during the eclipse. But how deep would the eclipse be? Would the resulting exposure on each pixel at minimum light be long enough to register a measurable signal? Seeing the light from the cool star! ESO PR Photo 30b/99 ESO PR Photo 30b/99 [Preview - JPEG: 400 x 464 pix - 156k] [Normal - JPEG: 800 x 927 pix - 584k] [High-Res - JPEG: 2292 x 2662 pix - 4.1M] ESO PR Photo 30c/99 ESO PR Photo 30c/99 [Preview - JPEG: 472 x 400 pix - 48k] [Normal - JPEG: 943 x 800 pix - 96k] Caption to ESO PR Photo 30b/99 : 18.5-min "drift" exposure with VLT ANTU and FORS1 of the sky field around the variable stellar system NN Ser (indicated with an arrow). The telescope moved 1 pixel (0.20 arcsec) every 3 seconds so that the images of the stars in the field are trailed from left to right. After some minutes, the very deep eclipse of NN Ser begins when the brightness drops dramatically during the first partial phase. The star is clearly visible at a constant level all through the total phase at minimum light. It then brightens during the second partial phase and is back to the former level after approximately 10.5 min. The FORS1 instrument was rotated by about 70° to ensure that the trail of NN Ser would not overlap those of the neighbouring stellar images during this special exposure. The field shown measures 2.7 x 2.7 armin 2 and may be compared with that shown in Photo 30a/99; it has the same orientation. Caption to ESO PR Photo 30c/99 : The light-curve of the variable stellar system NN Ser , as extracted from the drift exposure shown in Photo 30b/99 . The count rate is proportional to the brightness of the object; it is about 18,000 counts/pix outside the eclipse and decreases to about 70 counts during the total eclipse (since the full range of the eclipse is shown here, this low level is almost indistinguishable from 0 in this figure). Various properties of the two stars in the NN Ser system may be determined from the shape of the light-curve. The fact that the light-curve is "flat" at the bottom is a clear sign that the eclipse is total , i.e. the hot white dwarf star is completely hidden behind the cool red dwarf star. As ESO PR Photo 30b/99 shows, ANTU and FORS1 did manage this difficult observation! Aided by an excellent seeing of 0.5 arcsec, i.e. a good concentration of the light on each pixel, the recorded signal from NN Ser - although very faint - is well measurable at all times during the eclipse . In the mean, about 70 counts/pixel were registered at the minimum, down from about 18,000 outside the eclipse ( Photo 30c/99 ). The ratio is then about 250, corresponding to just over 6 magnitudes. The measured magnitude during eclipse is 23.0 in the V-band (green-yellow; wavelength 550 nm). Of even greater importance is the fact that the light-curve is found to be perfectly flat at the bottom, i.e. the eclipse is most certainly total . The white dwarf star is therefore being completely hidden as it moves behind the cooler and larger star, and we see only the latter during the eclipse. As explained above, this then allows to determine many of its properties. For instance, the fact that the light-curve has no obvious "soft shoulders" at the beginning and end of the total phase indicates that the white dwarf abruptly disappears from view. Thus the faint star cannot have a very extended atmosphere, otherwise the brightness change would have been more gradual. The total phase was found to last 7 m 37 s and each of the partial phases only 1 m 26 s. This shows that the orbit must be nearly perpendicular to the plane of the sky. This angle is referred to as the orbital inclination ; for NN Ser , it must be in the interval between 84° - 90°. A preliminary analysis indicates that the diameter of the cool star is between 200,000 and 245,000 km, i.e. about 1.5 times that of planet Jupiter. The white dwarf is even smaller; its diameter is between 25,000 and 31,000 km, or about twice the size of the Earth. The distance between the two stars is 660,000 km, or half the size of the Sun. Thus NN Ser is really a very small system - it would easily fit into our central star! The surface temperatures are widely different, about 55,000 and 2,800 degrees, respectively. By adding to this analysis earlier measurements of the orbital velocity of the white dwarf star, it is possible to estimate the mass of the cool star as between 0.10 and 0.14 solar masses. The white dwarf is significantly heavier, about 0.57 solar masses. Stellar objects with masses below approx. 0.08 solar mass are believed to be brown dwarfs , i.e. "still-born" stars in which nuclear fusion did not ignite. Since the mass of the cool star in NN Ser is near this limit, could it perhaps be such an object? A spectrum of the cool star ESO PR Photo 30d/99 ESO PR Photo 30d/99 [Preview - JPEG: 480 x 400 pix - 60k] [Normal - JPEG: 960 x 800 pix - 136k] Caption to ESO PR Photo 30d/99 : The spectrum of the cool dwarf star in the variable stellar system NN Ser . The 5 min exposure was obtained during the total phase of the eclipse, when the magnitude of the system was V = 23.0. Several TiO bands are clearly visible in this slightly smoothed tracing. A few deep and narrow "absorption" features are residuals from sky subtraction. The original resolution is 0.55 nm/pix. A spectral type of M6 or later is deduced for NN Ser . The spectrum of a more nearby (and hence much brighter) M6.5 dwarf star (temperature approx. 2600 degrees) is shown below for comparison. The VLT has already delivered the answer: it turns out to be no . The cool component of NN Ser may be a very small and faint object, but it is a real star that harbours nuclear processes in its interior. The temperature is on the high side for a brown dwarf, but the definite proof can only be obtained from the spectrum. ANTU and FORS1 were able to obtain a spectrum of NN Ser during the total eclipse, i.e. at a time when the visual magnitude was 23.0, cf. Photo 30d/99 . The exposure had to be limited to 5 min only, in order to ensure that there would be no contamination by extra light from the much brighter white dwarf companion star, as this is the case during the partial phases of the eclipse. Despite the difficult circumstances, it was possible to record a faint spectrum in the 600 - 900 nm (red - near-IR) wavelength interval. Although it is quite noisy, several molecular bands of TiO (titanium oxide) are well visible; VO (vanadium oxide) bands may also be present. They allow the classification of the spectrum as that of a very-late-type star, of spectral type M6 or later . This is in reasonable agreement with the mentioned temperature around 2800 degrees. In any case, this spectrum is quite unlike that of a brown dwarf, thus confirming that the cool companion star in NN Ser is a normal hydrogen-burning red dwarf star . NN Ser: a "missing link" in stellar theory The binary system NN Ser is now in an evolutionary stage that is referred to as the pre-cataclysmic phase. It will be followed by the cataclysmic phase , during which a gas stream will flow from the larger star to the smaller one. This phenomenon is characterized by frequent and abrupt increase in brightness. While many stars are known that are now in that unstable phase, only a few stars have ever been found to be in the preceding, transitory phase. Of these, NN Ser is the only one that has such a deep eclipse and for which it has now become possible to determine quite well the properties of the two components. NN Ser thus represents a most welcome example of a "missing link" in the theory of stellar evolution. It is therefore of great interest to perform further observations of such a rare object. They will include attempts to obtain more spectra to define the spectral type of the cool star very accurately. This will allow a critical check of current theories of atmospheres and evolutionary computations for the smallest and lightest stars. But for now, Reinhold Häfner looks forward to further nights at Paranal with the ESO astronomers there. "We worked together in a wonderful way during these demanding observations", he said, "and without their great support all of this would have been next to impossible!" Notes [1] These observations were carried out during "guaranteed observing time", allocated to the three German institutes that built the FORS instrument. More details about this instrument and related issues are available in ESO Press Release 14/98. [2] Astronomers designate variable stars according to the constellation in which they are seen in the sky and the order in which they are recognized as having variable brightness. For historical reasons, the first variable star in a given constellation (that is not already known by a greek letter, e.g. "Delta Cephei") is designated as "R" (e.g. "R Coronae Borealis"), the second as "S", etc. until "Z". Then follow "RR", "RS",..."RZ", "SS"..."SZ" until "ZZ" and only then from the beginning of the alphabet, "AA"..."AZ", "BA".. etc. until "QZ". How to obtain ESO Press Information ESO Press Information is made available on the World-Wide Web (URL: http://www.eso.org../ ). ESO Press Photos may be reproduced, if credit is given to the European Southern Observatory.

  13. The Impacts of SLC22A1 rs594709 and SLC47A1 rs2289669 Polymorphisms on Metformin Therapeutic Efficacy in Chinese Type 2 Diabetes Patients.

    PubMed

    Xiao, Di; Guo, Yu; Li, Xi; Yin, Ji-Ye; Zheng, Wei; Qiu, Xin-Wen; Xiao, Ling; Liu, Rang-Ru; Wang, Sai-Ying; Gong, Wei-Jing; Zhou, Hong-Hao; Liu, Zhao-Qian

    2016-01-01

    Background. We aimed to investigate the distributive characteristics of SLC22A1 rs594709 and SLC47A1 rs2289669 polymorphisms and their influence on metformin efficacy in Chinese T2DM patients. Methods. The distributions of SLC22A1 rs594709 and SLC47A1 rs2289669 polymorphisms were determined in 267 T2DM patients and 182 healthy subjects. Subsequently, 53 newly diagnosed patients who received metformin monotherapy were recruited to evaluate metformin efficacy. Results. No significant difference was found between T2DM patients and healthy subjects in SLC22A1 rs594709 and SLC47A1 rs2289669 allele frequencies and genotype frequencies. After metformin treatment, SLC22A1 rs594709 GG genotype patients showed a higher increase in FINS (p = 0.015) and decrease in HOMA-IS (p = 0.001) and QUICKI (p = 0.002) than A allele carriers. SLC47A1 rs2289669 GG genotype patients had a higher decrease in TChol (p = 0.030) and LDL-C (p = 0.049) than A allele carriers. Among SLC22A1 rs594709 AA genotype, patients with SLC47A1 rs2289669 AA genotype showed a higher decrease in FBG (p = 0.015), PINS (p = 0.041), and HOMA-IR (p = 0.014) than G allele carriers. However, among SLC22A1 rs594709 G allele carriers, SLC47A1 rs2289669 AA genotype patients showed a higher decrease in TChol (p = 0.013) than G allele carriers. Conclusion. Our data suggest that SLC22A1 rs594709 and SLC47A1 rs2289669 polymorphisms may influence metformin efficacy together in Chinese T2DM patients. PMID:26977146

  14. The Impacts of SLC22A1 rs594709 and SLC47A1 rs2289669 Polymorphisms on Metformin Therapeutic Efficacy in Chinese Type 2 Diabetes Patients

    PubMed Central

    Xiao, Di; Guo, Yu; Li, Xi; Yin, Ji-Ye; Zheng, Wei; Qiu, Xin-Wen; Xiao, Ling; Liu, Rang-Ru; Wang, Sai-Ying; Gong, Wei-Jing; Zhou, Hong-Hao; Liu, Zhao-Qian

    2016-01-01

    Background. We aimed to investigate the distributive characteristics of SLC22A1 rs594709 and SLC47A1 rs2289669 polymorphisms and their influence on metformin efficacy in Chinese T2DM patients. Methods. The distributions of SLC22A1 rs594709 and SLC47A1 rs2289669 polymorphisms were determined in 267 T2DM patients and 182 healthy subjects. Subsequently, 53 newly diagnosed patients who received metformin monotherapy were recruited to evaluate metformin efficacy. Results. No significant difference was found between T2DM patients and healthy subjects in SLC22A1 rs594709 and SLC47A1 rs2289669 allele frequencies and genotype frequencies. After metformin treatment, SLC22A1 rs594709 GG genotype patients showed a higher increase in FINS (p = 0.015) and decrease in HOMA-IS (p = 0.001) and QUICKI (p = 0.002) than A allele carriers. SLC47A1 rs2289669 GG genotype patients had a higher decrease in TChol (p = 0.030) and LDL-C (p = 0.049) than A allele carriers. Among SLC22A1 rs594709 AA genotype, patients with SLC47A1 rs2289669 AA genotype showed a higher decrease in FBG (p = 0.015), PINS (p = 0.041), and HOMA-IR (p = 0.014) than G allele carriers. However, among SLC22A1 rs594709 G allele carriers, SLC47A1 rs2289669 AA genotype patients showed a higher decrease in TChol (p = 0.013) than G allele carriers. Conclusion. Our data suggest that SLC22A1 rs594709 and SLC47A1 rs2289669 polymorphisms may influence metformin efficacy together in Chinese T2DM patients. PMID:26977146

  15. Association Analysis of NALCN Polymorphisms rs1338041 and rs61973742 in a Chinese Population with Isolated Cervical Dystonia

    PubMed Central

    Zhou, Qingqing; Yang, Jing; Cao, Bei; Chen, Yongping; Wei, Qianqian; Ou, Ruwei; Song, Wei; Zhao, Bi; Wu, Ying; Shang, Huifang

    2016-01-01

    Background. A genome-wide association study (GWAS) demonstrated a possible association between cervical dystonia (CD) and a sodium leak channel, nonselective (NALCN) gene. However, the association between NALCN and CD was largely unknown in Asian population. The present study was carried out to examine the associations between the two single nucleotide polymorphisms (SNPs) rs1338041 and rs61973742 in the NALCN gene and CD in a Chinese population. Methods. In a cohort of 201 patients with isolated CD, we genotyped the two SNPs rs1338041 and rs61973742 using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). We also included 289 unrelated, age- and sex-matched healthy controls (HCs) from the same region. Result. No significant differences were observed in either the genotype distributions or the minor allele frequencies (MAFs) of the two SNPs between the CD patients and the HCs. There were no significant differences between early-onset and late-onset CD patients, between patients with and without a positive family history of dystonia, or between patients with and without tremor or sensory tricks. Conclusion. Lack of association between the SNPs of NALCN and CD suggests that the SNPs of NALCN do not play a role in CD in a Chinese population.

  16. Star ratings. Stars of wonder.

    PubMed

    Dawes, David

    2002-09-12

    Analysis of trusts that changed their star-rating over the past two years indicates that a change of chief executive was not a significant factor. The length of time in post and the experience of the chief executive were also insignificant. This has serious implications for the theory behind franchising and the evaluation of franchised trusts. Holding chief executives to account for the organisation's performance within their first 12 months is unlikely to be effective. PMID:12357738

  17. Investigation of IL-21 gene polymorphisms (rs2221903, rs2055979) in cases with multiple sclerosis of Azerbaijan, Northwest Iran

    PubMed Central

    Gharibi, Tohid; Kazemi, Tohid; Aliparasti, Mohammad Reza; Farhoudi, Mehdi; Almasi, Shohreh; Dehghanzadeh, Rashedeh; seyfizadeh, Narges; Babaloo, Zohreh

    2015-01-01

    Background: Multiple Sclerosis (MS) is a chronic inflammatory demyelinating disease of the Central Nervous System that is immunologically mediated in genetically susceptible individuals. IL-21, a cytokine produced by TCD4+ cells, particularly by Th-17 cells, is believed to play an important role in the MS pathogenesis. Objective: This study was performed to investigate the impact of genetic polymorphisms in IL-21 gene on MS susceptibility and clinical profiles. Methods: Seventy Iranian patients with clinically definite relapsing-remitting MS and 110 age, sex and ethic matched controls were genotyped for IL-21 gene polymorphisms using PCR-RFLP method. Results: Our results showed that the IL-21 rs2221903 SNP is not polymorphic in our population. Also, the allelic and genotypic frequencies of the IL-21 rs2055979 did not differ significantly between the MS patients and controls (P = 0.413 and P = 0.565 respectively, and OR = 1.122, 95% CI = 0.79-1.87 for T allele). However, our results showed that IL-21 rs2055979 (G/T) T allele positive (TT+GT) MS patients had lower (PI ≤ 1.5) disease progression compared to rs2055979 T allele negative (GG) patients (P = 0.009). Conclusion: Our results showed that no outstanding association exists between IL-21 alleles and susceptibility to MS. However, our clinical analysis showed significant association of IL-21 gene polymorphism with the progression of multiple sclerosis disease. Our results indicate that the G allele promotes, or the T allele protects against disease progression. To clarify the role of IL-21 rs2055979 in MS pathogenesis, further comprehensive studies with larger sample sizes among different ethnicity populations are recommended. PMID:26155434

  18. Binary stars.

    PubMed

    Paczynacuteski, B

    1984-07-20

    Most stars in the solar neighborhood are either double or multiple systems. They provide a unique opportunity to measure stellar masses and radii and to study many interesting and important phenomena. The best candidates for black holes are compact massive components of two x-ray binaries: Cygnus X-1 and LMC X-3. The binary radio pulsar PSR 1913 + 16 provides the best available evidence for gravitational radiation. Accretion disks and jets observed in close binaries offer a very good testing ground for models of active galactic nuclei and quasars. PMID:17749544

  19. Association between microRNA-196a2 rs11614913, microRNA-146a rs2910164, and microRNA-423 rs6505162 polymorphisms and esophageal cancer risk: A meta-analysis

    PubMed Central

    Ji, Hong-Hai; Hong-Luo; Huang, Guang-Lei; Yin, Hai-Xin; Xu, Ping; Luo, Si-Yang; Song, Ju-Kun

    2015-01-01

    Many observational studies have found that microRNA-196a2 rs11614913, microRNA-146a rs2910164, and microRNA-423 rs6505162 are associated with esophageal cancer risk. However, the results were mixed and inconsistent among these studies. We conducted a meta-analysis to assess the relationship between the polymorphisms of three microRNAs and esophageal cancer susceptibility. We systematically searched the PubMed and EMBASE databases to screen relevant studies. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were used to compute the risk of esophageal cancer. Because of the differences in ethnicities, sources of controls, and genotyping methods, the meta-analysis was conducted using a random-effect model regardless of heterogeneity. To further explore potential heterogeneity, we performed subgroup and sensitivity analyses, and publication bias was also evaluated. A total of 6 case-control studies on microRNA-196a2 rs11614913, 4 studies on microRNA-146a rs2910164, and 4 studies on microRNA-423 rs6505162 were considered eligible in the meta-analysis. No statistical association was found between microRNA-196a2 rs11614913, microRNA-146a rs2910164, and microRNA-423 rs6505162 polymorphisms and esophageal cancer susceptibility in any genetic model. Subgroup and sensitivity analyses showed similar results. In summary, based on the currently limited proof, no association exists between microRNA-196a2 rs11614913, microRNA-146a rs2910164, and microRNA-423 rs6505162 polymorphism and esophageal cancer risk. However, the result should be cautiously interpreted because of the heterogeneity among studies. Large, high quality clinical trials are required to verify our findings.

  20. Nuclear Export and Retention Signals in the RS Domain of SR Proteins

    PubMed Central

    Cazalla, Demian; Zhu, Jun; Manche, Lisa; Huber, Elisabeth; Krainer, Adrian R.; Cceres, Javier F.

    2002-01-01

    Splicing factors of the SR protein family share a modular structure consisting of one or two RNA recognition motifs (RRMs) and a C-terminal RS domain rich in arginine and serine residues. The RS domain, which is extensively phosphorylated, promotes protein-protein interactions and directs subcellular localization andin certain situationsnucleocytoplasmic shuttling of individual SR proteins. We analyzed mutant versions of human SF2/ASF in which the natural RS repeats were replaced by RD or RE repeats and compared the splicing and subcellular localization properties of these proteins to those of SF2/ASF lacking the entire RS domain or possessing a minimal RS domain consisting of 10 consecutive RS dipeptides (RS10). In vitro splicing of a pre-mRNA that requires an RS domain could take place when the mutant RD, RE, or RS10 domain replaced the natural domain. The RS10 version of SF2/ASF shuttled between the nucleus and the cytoplasm in the same manner as the wild-type protein, suggesting that a tract of consecutive RS dipeptides, in conjunction with the RRMs of SF2/ASF, is necessary and sufficient to direct nucleocytoplasmic shuttling. However, the SR protein SC35 has two long stretches of RS repeats, yet it is not a shuttling protein. We demonstrate the presence of a dominant nuclear retention signal in the RS domain of SC35. PMID:12215544

  1. EFEMP1 rs3791679 polymorphism was associated with susceptibility to glioma

    PubMed Central

    Qin, Guoqiang; Qi, Songtao; Lu, Dan; Yu, Jiangjun; Huang, Weimin; Yu, Lei

    2015-01-01

    We conducted a case-control study in a Chinese population, and investigated the association between four SNPs (rs3791679, rs1346786, rs1344733 and rs727878) in EFEMP1 and development of glioma. A case-control study was taken in the present study. The rs3791679, rs1346786, rs1344733 and rs727878 gene polymorphisms were analyzed using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. A total of 159 patients with glioma and 364 controls were collected between July 2012 and June 2014. By unconditional logistic regression analysis, we found that individuals carrying the AA genotype and GA+AA genotype were associated with development of glioma when compared with the GG genotype, and the adjusted ORs (95% CI) were 2.13 (1.15-3.90) and 1.55 (1.04-2.32), respectively. However, we did not find that rs1346786, rs1344733 and rs727878 were significantly associated with development of glioma. Moreover, we found that the GA+AA genotype of rs3791679 was associations with a heavy increased risk of glioma in patients who have family history of cancers, and the OR (95% CI) was 6.81 (1.17-48.06). The results of our study suggested an association between the rs3791679 polymorphism and an elevated risk of glioma, especially in those with family history of glioma. PMID:26823870

  2. Association between CYP17A1 rs3824755 and rs743572 gene polymorphisms and Alzheimer's disease in the Chinese Han population.

    PubMed

    Xie, Li; Yan, Huacheng; Shi, Lei; Kong, Yanying; Huang, Mukun; Li, Jian; Li, Jin; Zheng, Jiaqiang; Zhao, Yongpan; Zhao, Shujin

    2016-04-01

    The CYP17A1 gene encodes cytochrome P450c17α, an enzyme that catalyzes the formation of sex hormones, which have been linked to the pathogenesis of Alzheimer's disease (AD). An association between the CYP17A1 rs743572 single nucleotide polymorphism (SNP) and AD has been reported; however, the findings are controversial. In the present study, we investigated the association between rs743572 and another SNP, rs3824755, and AD risk in a Chinese Han population (n=207 patients and 239 controls), and their interaction with the apolipoprotein E (APOE) e4 allele. We found that the C allele and GC+CC genotypes of rs3824755 conferred protection against AD only in APOE e4 carriers. Both rs3824755 and rs743572 polymorphisms showed interactions with APOE e4. The C allele and GC+CC genotypes of rs3824755 acted as protective factors that decreased the risk of APOE e4 in AD. The CYP17A1 rs743572G allele and AG+GG genotypes were found to be potential risk factors that act synergetically with APOE e4. Moreover, the CA and GG haplotypes were protective and conferred a slight risk, respectively, in APOE e4 carriers. These results indicate that CYP17A1 rs3824755 and rs743572 are associated with AD in the Chinese Han population and act in combination with APOE e4. PMID:26940238

  3. Symbiotic Stars on Asiago Archive Plates

    NASA Astrophysics Data System (ADS)

    Jurdana-Šepić, Rajka; Munari, Ulisse

    2010-01-01

    The Asiago photographic archive has been searched for plates containing the symbiotic stars AS 210, AS 327, AX Per, BF Cyg, CI Cyg, DT Ser, EG And, GH Gem, Hen 2-442, Hen 3-1591, HM Sge, MaC 1-17, NSV 11776, Pe 2-16, Pt 1, PU Vul, RS Oph, T CrB, UV Aur, V1016 Cyg, V1329 Cyg, V352 Aql, V4018 Sgr, Wray 15-1470, and Z And. A total of 1617 good-quality plates imaging the program stars have been found and their brightness has been estimated using the Henden & Munari UBVRCIC local photometric sequences. The results for the objects with most abundant measurements are discussed.

  4. Cool stars, stellar systems, and the sun; Proceedings of the 6th Cambridge Workshop, Seattle, WA, Sept. 18-21, 1989

    SciTech Connect

    Wallerstein, G.

    1990-01-01

    The present conference on cool stars, stellar systems, and the sun encompasses stellar chromospheres and coronae, binary stars, the stellar evolution of contracting stars and red giants, stellar evolution abundances of the elements, mass loss and envelopes, and stellar pulsation. Specific issues addressed include theories regarding the acoustic and magnetic heating of stellar chromospheres and coronae, stellar granulation, wave heating in magnetic flux tubes, observations of the solar Ca-II lines, longitudinal-transverse magnetic tube waves in the solar atmosphere, radio emission from rapidly rotating cool giant stars, and spot temperatures and area coverages on active dwarf stars. Also addressed are the optical and UV spectra of RS-CVn stars, emission lines from T-Tauri stars, the spectroscopy of HR1614 group stars, red giants in external galaxies, the rotation of evolved stars, the transition from red giant to planetary nebula, and radiative transfer in the dynamic atmospheres of variable stars.

  5. RS Ophiuchi: The Gift that Keeps on Giving

    NASA Astrophysics Data System (ADS)

    Starrfield, S.

    2008-12-01

    RS Oph experienced its sixth recorded outburst in 2006 and was observed in virtually every wavelength region from hard X-rays to the radio. Each observation, especially those with instruments that have come online since its last outburst in 1985, provided new and exciting information about the explosion. As a result, some of us organized a second workshop on the RS Oph outburst and it was held in June 2007 at Keele University. I gave the lead off talk in which I presented a number of questions to be discussed during the workshop, a brief summary of what had been discovered in previous outbursts concentrating on the ultraviolet studies with IUE, and a few observations of the 2006 outburst concentrating on the results from Swift and HST.

  6. Narcolepsy goes to school: the three Rs for school nurses.

    PubMed

    Gow, Monica

    2014-03-01

    The sleep disorder narcolepsy most often first appears in the teen years. It can dash the dreams of optimistic, intelligent students. It can make some students the target of nasty jokes and bullying, leaving them depressed and socially isolated. It can challenge children's self-esteem, and lowered self-esteem may last a lifetime. Typically, children with narcolepsy gain weight and have no interest in participating in anything. Many constantly feel extreme tiredness, and they may experience cataplexy. School nurses and teachers can help if they know the symptoms and practice the 3 Rs of narcolepsy: Recognize the symptoms of narcolepsy; Respect that narcolepsy is a lifelong, serious sleep disorder that needs treatment; and Refer students who exhibit symptoms to medical professionals. The 3 Rs will help students living with this lifelong disorder to get a fair shake in life's academic, social, and career arenas. PMID:24707660

  7. Journal editorial policies, animal welfare, and the 3Rs.

    PubMed

    Osborne, Nicola J; Payne, Daisy; Newman, Michael L

    2009-12-01

    This study evaluates the editorial policies of a randomized sample of English language peer-reviewed journals that publish original research involving the use of animals. The aim is to identify whether journals have editorial policies relating to the use of animals in the research that they are prepared to publish and whether any policies are likely to promote animal welfare and dissemination of information on the 3Rs (reduction, refinement, replacement) within the scientific community. The results demonstrate that a significant proportion of journals publishing original research involving animals do not have any editorial policy relating to the use of animals. Of those journals that do have policies the majority simply request that the research be carried out in accordance with standard regulatory requirements. This paper aims to provide editors and publishers with the information they need to review their own editorial policies to ensure they are fulfilling their potential to promote animal welfare and dissemination of the 3Rs. PMID:20013503

  8. Radiation Dry Bias of the Vaisala RS92 Humidity Sensor

    NASA Technical Reports Server (NTRS)

    Vomel, H.; Selkirk, H.; Miloshevich, L.; Valverde-Canossa, J.; Valdes, J.; Kyro, E.; Kivi, R.; Stolz, W.; Peng, G.; Diaz, J. A.

    2007-01-01

    The comparison of simultaneous humidity measurements by the Vaisala RS92 radiosonde and by the Cryogenic Frostpoint Hygrometer (CFH) launched at Alajuela, Cosla Rica, during July 2005 reveals a large solar radiation dry bias of the Vaisala RS92 humidity sensor and a minor temperature-dependent calibration error. For soundings launched at solar zenith angles between 10" and 30 , the average dry bias is on the order of 9% at the surface and increases to 50% at 15 km. A simple pressure- and temperature-dependent correction based on the comparison with the CFH can reduce this error to less than 7% at all altitudes up to 15.2 km, which is 700 m below the tropical tropopause. The correction does not depend on relative humidity, but is able to reproduce the relative humidity distribution observed by the CFH.

  9. The enigmatic star EZ Pegasi - A mystery solved?

    NASA Technical Reports Server (NTRS)

    Howell, S. B.; Bopp, B. W.

    1985-01-01

    EZ Peg, a ninth-magnitude G star that has been classified by various authors as an irregular variable, a U Gem system, and a contact binary, is shown to have all the spectroscopic and photometric characteristics of an active-chromosphere RS CVn binary. It is suggested that the reported outburst of 1943, when the spectrum appeared to be that of a B star, never occurred. The strong Ca II H and K reversals, viewed with low spectral resolution, caused the photospheric Ca II absorption to appear abnormally weak, mimicking a much earlier spectral type.

  10. Activity Cycles in Stars with Highly Active Chromospheres

    NASA Astrophysics Data System (ADS)

    Guinan, Edward F.

    The extended lifetime of the IUE satellite has provided an unique and unanticipated opportunity to examine the long-term evolution of magnetic activity on active chromospheric stars. We propose to obtain further IUE observations of the highly active RS CVn stars V711 Tauri, lambda Andromedae, II Pegasi, and UX Arietis in conjunction with groundbased optical and radio observations, and possibly ROSAT X-ray observations. In addition we would continue IUE observations of the unusual rapidly rotating early G giant, FK Comae, which, although not in the RS CVn category, shares a similarly high level of magnetic activity. These five stars have the most extensive IUE archival coverage for stars of their type and have almost continuous ground-based photometric coverage from about 1975 onward. We aim to trace the long-term development of magnetic activity on these stars: a detailed study of the UV emission-like fluxes will enable us to follow the variations in chromospheric and transition-region activity over an interval of 12-16 years. Optical observations reveal variations in photospheric (starspot) activity: the starspot regions are large (up to 30% of the stellar surface) and vary significantly with time. The main aim of the proposed research is to examine the relationship between chromospheric, transition-region, and photospheric active regions. Elucidation of the role of white-light faculae vis-a-vis spots in effecting stellar irradiance changes is also desirable.

  11. Higher Curvature Effects in the ADD and RS Models

    SciTech Connect

    Rizzo, Thomas G.; /SLAC

    2006-07-05

    Over the last few years several extra-dimensional models have been introduced in attempt to deal with the hierarchy problem. These models can lead to rather unique and spectacular signatures at Terascale colliders such as the LHC and ILC. The ADD and RS models, though quite distinct, have many common feature including a constant curvature bulk, localized Standard Model(SM) fields and the assumption of the validity of the EH action as a description of gravitational interactions.

  12. Alkaline protease from Thermoactinomyces sp. RS1 mitigates industrial pollution.

    PubMed

    Verma, Amit; Ansari, Mohammad W; Anwar, Mohmmad S; Agrawal, Ruchi; Agrawal, Sanjeev

    2014-05-01

    Proteases have found a wide application in the several industrial processes, such as laundry detergents, protein recovery or solubilization, prion degradation, meat tenderizations, and in bating of hides and skins in leather industries. But the main hurdle in industrial application of proteases is their economical production on a large scale. The present investigation aimed to exploit the locally available inexpensive agricultural and household wastes for alkaline protease production using Thermoactinomyces sp. RS1 via solid-state fermentation (SSF) technique. The alkaline enzyme is potentially useful as an additive in commercial detergents to mitigate pollution load due to extensive use of caustic soda-based detergents. Thermoactinomyces sp. RS1 showed good protease production under SSF conditions of 55 C, pH 9, and 50 % moisture content with potato peels as solid substrate. The presented findings revealed that crude alkaline protease produced by Thermoactinomyces sp. RS1 via SSF is of potential application in silver recovery from used X-ray films. PMID:24122212

  13. Association Study of rs1333040 and rs1004638 Polymorphisms in the 9p21 Locus with Coronary Artery Disease in Southwest of Iran

    PubMed Central

    Golabgir Khademi, Khadijeh; Foroughmand, Ali Mohammad; Galehdari, Hamid; Yazdankhah, Saied; Pourmahdi Borujeni, Mahdi; Shahbazi, Zahra; Dinarvand, Parvaneh

    2016-01-01

    Background: Coronary artery disease (CAD) is a multifactorial and heterogenic disease. Recently, genome-wide association studies have reported that rs1333040 (C/T) and rs1004638 (A/T) single nucleotide polymorphisms (SNPs) in the 9p21 locus have very strong association with CAD. This study aimed to examine these associations in Southwest of Iran. Methods: Blood samples were collected from 200 CAD patients and 110 healthy individuals with no CAD. The association of two SNPs with CAD was evaluated by PCR and restriction fragment length polymorphism. Results: Chi-square test showed no association between rs1333040 SNP and CAD (X2: 4.66, df: 2, P=0.09). Also, there was no association between rs1004638 SNP and CAD (X2: 0.27, df: 2, P=0.88). Conclusion: No association was observed between rs1333040 and rs1004638 SNPs in the 9P21 region and CAD in Southwest of Iran. PMID:26597055

  14. High-Resolution N-Band Observations of the Nova RS Ophiuchi with the Keck Interferometer Nuller

    NASA Technical Reports Server (NTRS)

    Barry, R. K.; Danchi, W. C.; Sokoloski, J. L.; Koresko, C.; Wisniewski, J. P.; Serabyn, E.; Traub, W.; Kuchner, M.; Greenhouse, M. A.

    2007-01-01

    We report new observations of the nova RS Ophiuchi (RS Oph) using the Keck Interferometer Nulling Instrument, approximately 3.8 days following the most recent outburst that occurred on 2006 February 12. The Keck Interferometer Nuller (KIN) operates in K-band from 8 to 12.5 pm in a nulling mode, which means that the central broad-band interference fringe is a dark fringe - with an angular width of 25 mas at mid band - rather than the bright fringe used ill a conventional optical interferometer. In this mode the stellar light itself is suppressed by the destructive fringe, effectively enhancing the contrast of the circumstellar material located near the star. By subsequently shifting the neighboring bright fringe onto the center of the source brightness distribution and integrating, a second spatial regime dominated by light from the central portion of the source is almost simultaneously sampled. The nulling technique is the sparse aperture equivalent of the conventional corongraphic technique used in filled aperture telescopes. By fitting the unique KIK inner and outer spatial regime data, we have obtained an angular size of the mid-infrared continuum of 6.2, 4.0. or 5.4 mas for a disk profile, gaussian profile (fwhm), and shell profile respectively. The data show evidence of enhanced neutral atomic hydrogen emission located in the inner spatial regime relative to the outer regime. There is also evidence of a 9.7 micron silicate feature seen outside of this region. Importantly, we see spectral lines excited by the nova flash in the outer region before the blast wave reaches these regions. These lines are from neutral, weakly excited atoms which support the following interpretation. We discuss the present results in terms of a unifying model of the system that includes an increase in density in the plane of the orbit of the two stars created by a spiral shock wave caused by the motion of the stars through the cool wind of the red giant star. These data show the power and potential of the nulling technique which has been developed for the detection of Earth-like planets around nearby stars for the Terrestrial Planet Finder Mission and Darwin missions.

  15. The long-period Galactic Cepheid RS Puppis. III. A geometric distance from HST polarimetric imaging of its light echoes

    NASA Astrophysics Data System (ADS)

    Kervella, P.; Bond, H. E.; Cracraft, M.; Szabados, L.; Breitfelder, J.; Mrand, A.; Sparks, W. B.; Gallenne, A.; Bersier, D.; Fouqu, P.; Anderson, R. I.

    2014-12-01

    As one of the most luminous Cepheids in the Milky Way, the 41.5-day RS Puppis is an analog of the long-period Cepheids used to measure extragalactic distances. An accurate distance to this star would therefore help anchor the zero-point of the bright end of the period-luminosity relation. But, at a distance of about 2 kpc, RS Pup is too far away for measuring a direct trigonometric parallax with a precision of a few percentage points with existing instrumentation. RS Pup is unique by being surrounded by a reflection nebula whose brightness varies as pulses of light from the Cepheid propagate outward. We present new polarimetric imaging of the nebula obtained with HST/ACS. The derived map of the degree of linear polarization pL allows us to reconstruct the three-dimensional structure of the dust distribution. To retrieve the scattering angle from the pL value, we consider two different polarization models, one based on a Milky Way dust mixture and one assuming Rayleigh scattering. Considering the derived dust distribution in the nebula, we adjust a model of the phase lag of the photometric variations over selected nebular features to retrieve the distance of RS Pup. We obtain a distance of 1910 80 pc (4.2%), corresponding to a parallax of ? = 0.524 0.022 mas. The agreement between the two polarization models that we considered is good, but the final uncertainty is dominated by systematics in the adopted model parameters. The distance we obtain is consistent with existing measurements from the literature, but light echoes provide a distance estimate that is not subject to the same systematic uncertainties as other estimators (e.g., the Baade-Wesselink technique). RS Pup therefore provides an important fiducial for calibrating the systematic uncertainties of the long-period Cepheid distance scale. 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 #13454.Table 1 and Appendix A are available in electronic form at http://www.aanda.org

  16. Another functional frame-shift polymorphism of DEFB126 (rs11467497) associated with male infertility

    PubMed Central

    Duan, Shiwei; Shi, Changgeng; Chen, Guowu; Zheng, Ju-fen; Wu, Bin; Diao, Hua; Ji, Lindan; Gu, Yihua; Xin, Aijie; Wu, Yancheng; Zhou, Weijin; Miao, Maohua; Xu, Limin; Li, Zheng; Yuan, Yao; Wang, Peng; Shi, Huijuan

    2015-01-01

    DEFB126 rs140685149 mutation was shown to cause sperm dysfunction and subfertility. Indel rs11467497 is another 4-nucleotide frame-shift mutation (151bp upstream of rs140685149) that leads to the premature termination of translation and the expression of peptide truncated at the carboxyl terminus. In the present study, we performed a comprehensive association study to check the contribution of rs140685149 and rs11467497 to male infertility. Our results confirmed the previous findings that there was no association between rs140685149 and sperm motility. In contrast, we found a significant association of another indel rs11467497 with male infertility. Moreover, rs11467497 was shown to be associated with higher number of round cells in the infertile males with low sperm motility. Surprisingly, the two mutations commonly existed in the sperm donors (n = 672), suggesting a potential application of the two indels in the screening for eligible sperm donors. Western blotting assays showed the sperms with rs140685149 2-nt deletion tended to have unstable DEFB126 protein in contrast of no DEFB126 protein expressed in the sperms with rs11467497 4-nt deletion, suggesting a more severe consequence caused by rs11467497 mutation. In conclusion, our study presented a significant contribution of another functional frame-shift polymorphism of DEFB126 (rs11467497) to male infertility. PMID:25721098

  17. FNDC5 (irisin) gene and exceptional longevity: a functional replication study with rs16835198 and rs726344 SNPs.

    PubMed

    Sanchis-Gomar, Fabian; Garatachea, Nuria; He, Zi-hong; Pareja-Galeano, Helios; Fuku, Noriyuki; Tian, Ye; Arai, Yasumichi; Abe, Yukiko; Murakami, Haruka; Miyachi, Motohiko; Yvert, Thomas; Santiago, Catalina; Venturini, Letizia; Fiuza-Luces, Carmen; Santos-Lozano, Alejandro; Rodríguez-Romo, Gabriel; Ricevuti, Giovanni; Hirose, Nobuyoshi; Emanuele, Enzo; Lucia, Alejandro

    2014-01-01

    Irisin might play an important role in reducing the risk of obesity, insulin resistance, or several related diseases, and high irisin levels may contribute to successful aging. Thus, the irisin precursor (FNDC5) gene is a candidate to influence exceptional longevity (EL), i.e., being a centenarian. It has been recently shown that two single-nucleotide polymorphisms (SNPs) in the FNDC5 gene, rs16835198 and rs726344, are associated with in vivo insulin sensitivity in adults. We determined luciferase gene reporter activity in the two above-mentioned SNPs and studied genotype distributions among centenarians (n = 175, 144 women) and healthy controls (n = 347, 142 women) from Spain. We also studied an Italian [79 healthy centenarians (40 women) and 316 healthy controls (156 women)] and a Japanese cohort [742 centenarians (623 women) and 499 healthy controls (356 women)]. The rs726344 SNP had functional significance, as shown by differences in luciferase activity between the constructs of this SNP (all P ≤ 0.05), with the variant A-allele having higher luciferase activity compared with the G-allele (P = 0.04). For the rs16835198 SNP, the variant T-allele tended to show higher luciferase activity compared with the G-allele (P = 0.07). However, we found no differences between genotype/allele frequencies of the two SNPs in centenarians versus controls in any cohort, and no significant association (using logistic regression adjusted by sex) between the two SNPs and EL. Further research is needed with different cohorts as well as with additional variants in the FNDC5 gene or in other genes involved in irisin signaling. PMID:25427998

  18. Liver X Receptor-α polymorphisms (rs11039155 and rs2279238) are associated with susceptibility to vitiligo.

    PubMed

    Agarwal, Silky; Kaur, Gurjinder; Randhawa, Rohit; Mahajan, Vikram; Bansal, Rohit; Changotra, Harish

    2016-06-01

    Vitiligo is a complex genetic skin depigmentation disorder caused by the destruction of melanocyte from the lesional site. Liver X Receptor-α (LXR-α) expression is upregulated in the melanocytes from perilesional skin as compared to the normal skin of vitiligo patient suggesting its involvement in vitiligo pathogenesis. Polymorphisms in LXR-α have been associated with several diseases including cardiovascular disease, polycystic ovary syndrome, cancer, inflammatory bowel disease and diabetes. In this study, for the first time, we have investigated the association of LXR-α gene polymorphisms and risk of vitiligo. Sixty six vitiligo patients and 75 matched healthy control subjects who did not have any history of vitiligo or any other autoimmune disorder were recruited. The DNA isolated from patients and healthy controls was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for both rs11039155 (- 6 G > A) and rs2279238 (+ 1257 C > T) variants. Our data suggest significant association between the LXR-α gene polymorphisms and vitiligo susceptibility (rs11039155: odds ratio (OR) = 1.99, 95% CI = 1.07-3.71, p = 0.03; rs2279238: OR = 1.70, 95% CI = 1.06-2.73, p = 0.027). Our results provide an evidence that the LXR-α - 6A and + 1257T alleles contribute to risk of vitiligo in North Indian population and highlight the importance of this gene in the vitiligo pathogenesis. PMID:27014589

  19. Liver X Receptor-α polymorphisms (rs11039155 and rs2279238) are associated with susceptibility to vitiligo

    PubMed Central

    Agarwal, Silky; Kaur, Gurjinder; Randhawa, Rohit; Mahajan, Vikram; Bansal, Rohit; Changotra, Harish

    2016-01-01

    Vitiligo is a complex genetic skin depigmentation disorder caused by the destruction of melanocyte from the lesional site. Liver X Receptor-α (LXR-α) expression is upregulated in the melanocytes from perilesional skin as compared to the normal skin of vitiligo patient suggesting its involvement in vitiligo pathogenesis. Polymorphisms in LXR-α have been associated with several diseases including cardiovascular disease, polycystic ovary syndrome, cancer, inflammatory bowel disease and diabetes. In this study, for the first time, we have investigated the association of LXR-α gene polymorphisms and risk of vitiligo. Sixty six vitiligo patients and 75 matched healthy control subjects who did not have any history of vitiligo or any other autoimmune disorder were recruited. The DNA isolated from patients and healthy controls was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for both rs11039155 (− 6 G > A) and rs2279238 (+ 1257 C > T) variants. Our data suggest significant association between the LXR-α gene polymorphisms and vitiligo susceptibility (rs11039155: odds ratio (OR) = 1.99, 95% CI = 1.07–3.71, p = 0.03; rs2279238: OR = 1.70, 95% CI = 1.06–2.73, p = 0.027). Our results provide an evidence that the LXR-α − 6A and + 1257T alleles contribute to risk of vitiligo in North Indian population and highlight the importance of this gene in the vitiligo pathogenesis. PMID:27014589

  20. Physico-chemical, functional and structural properties of RS3/RS4 from kidney bean (Phaseolus vulgaris) cultivars.

    PubMed

    Gani, Adil; Jan, Amreen; Shah, Asima; Masoodi, F A; Ahmad, Mudasir; Ashwar, Bilal Ahmad; Akhter, Rehana; Wani, Idrees Ahmed

    2016-06-01

    Starch isolated from four kidney bean cultivars (Yellow bean, Red bean, Black bean and White bean) were physically and chemically modified in order to prepare resistant starch (RS3/RS4). Following the Heat-moisture treatment (HMT) and Citric acid modification (CT) of the native starch, the amylose content got decreased whereas bulk and tapped density (g/ml) increased. Both HMT and CT reduced the swelling power and the solubility of native starch. Pasting temperature increased and peak, breakdown, final, and set-back viscosity decreased after both the modifications. Fourier Transform Infrared Spectroscopy (FTIR) analysis displayed peaks at 1020cm(-1) in HMT and 1724cm(-1) in CT starches. Differential Scanning Calorimetry (DSC) analysis revealed that samples were more stable after modification. X-ray diffraction (XRD) analysis revealed reordering of chain segments to more crystalline structure. These results suggested modifications resulted in starch with improved properties and could be a possible method for the RS preparation with better thermal stability. PMID:26976068

  1. Role of IL-17A rs2275913 and IL-17F rs763780 polymorphisms in risk of cancer development: an updated meta-analysis

    PubMed Central

    Dai, Zhi-Ming; Zhang, Tian-Song; Lin, Shuai; Zhang, Wang-Gang; Liu, Jie; Cao, Xing-Mei; Li, Hong-Bao; Wang, Meng; Liu, Xing-Han; Liu, Kang; Li, Shan-Li; Dai, Zhi-Jun

    2016-01-01

    Single nucleotide polymorphisms (SNPs) in the interleukin-17 (IL-17) gene have been shown to be correlated with susceptibility to cancer. However, various studies report different results of this association. The aim of the present work was to clarify the effects of IL-17A G197A (rs2275913) and IL-17F T7488C (rs763780) polymorphisms on cancer risk. We performed systematic searches of the PubMed and CNKI databases to obtain relevant publications. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to evaluate the association of rs2275913 and rs763780 polymorphisms with cancer risk. Data were extracted from the selected studies, and statistical analysis was conducted using the STATA software. Our results indicated that rs2275913 and rs763780 polymorphisms significantly increase cancer risk, especially in gastric cancers. Subgroup analysis suggested the existence of a significant correlation between rs763780 polymorphism and cancer susceptibility in Caucasian populations. This updated meta-analysis confirms that rs2275913 and rs763780 polymorphisms are highly associated with increased risk for multiple forms of cancer. PMID:26843459

  2. Pincer-CNC mononuclear, dinuclear and heterodinuclear Au(iii) and Pt(ii) complexes supported by mono- and poly-N-heterocyclic carbenes: synthesis and photophysical properties.

    PubMed

    Gonell, S; Poyatos, M; Peris, E

    2016-04-01

    A family of cyclometallated Au(iii) and Pt(ii) complexes containing a CNC-pincer ligand (CNC = 2,6-diphenylpyridine) supported by pyrene-based mono- or bis-NHC ligands have been synthesized and characterized, together with the preparation of a Pt-Au hetero-dimetallic complex based on a Y-shaped tris-NHC ligand. The photophysical properties of all the new species and of two related Ru(ii)-arene complexes were studied and compared. Whereas the pyrene-based complexes only exhibit emission in solution, those containing the Y-shaped tris-NHC ligand are only luminescent when dispersed in poly(methyl methacrylate) (PMMA). In particular, the pyrene-based complexes were found to be emissive in the range of 373-440 nm, with quantum yields ranging from 3.1 to 6.3%, and their emission spectra were found to be almost superimposable, pointing to the fluorescent pyrene-centered nature of the emission. This observation suggests that the emission properties of the pyrene fragment may be combined with some of the numerous applications of NHCs as supporting ligands allowing, for instance, the design of biological luminescent agents. PMID:26911885

  3. Natural antioxidants exhibit chemopreventive characteristics through the regulation of CNC-bZip transcription factors in estrogen-induced breast carcinogenesis

    PubMed Central

    Chatterjee, Anwesha; Ronghe, Amruta; Singh, Bhupendra; Bhat, Nimee K.; Chen, Jie; Bhat, Hari K.

    2014-01-01

    The objective of the present study was to characterize the role of resveratrol (Res) and vitamin C (VC) in prevention of estrogen-induced breast cancer through regulation of CNC b-zip transcription factors. Human breast epithelial cell line MCF-10A was treated with 17β-estradiol (E2) and VC or Res with or without E2. mRNA and protein expression levels of CNC b-zip transcription factors: Nrf1, Nrf2, Nrf3 and Nrf2-regulated antioxidant enzymes SOD3 and NQO1 were quantified. Treatment with E2 suppressed while VC and Res prevented E2-mediated decrease in the expression levels of SOD3, NQO1, Nrf2 mRNA and protein in MCF-10A cells. Treatment with E2, Res or VC significantly increased mRNA and protein expression levels of Nrf1. 17β-estradiol treatment significantly increased but VC or Res decreased Nrf3 mRNA and protein expression levels. Our studies demonstrate that estrogen-induced breast cancer might be prevented through up-regulation of antioxidant enzymes via Nrf-dependent pathways. PMID:25130429

  4. Doppler images of the RS CVn binary II Pegasi during the years 1994-2002

    NASA Astrophysics Data System (ADS)

    Lindborg, M.; Korpi, M. J.; Hackman, T.; Tuominen, I.; Ilyin, I.; Piskunov, N.

    2011-02-01

    Aims: We publish 16 Doppler imaging temperature maps for the years 1994-2002 of the active RS CVn star II Peg. The six maps from 1999-2002 are based on previously unpublished observations. Through Doppler imaging we want to study the spot evolution of the star and in particular compare this with previous results showing a cyclic spot behaviour and persistent, active longitudes. Methods: The observations were collected with the SOFIN spectrograph at the Nordic Optical Telescope. The temperature maps were calculated using a Doppler imaging code based on Tikhonov regularization. Results: During 1994-2001, our results show a consistent trend in the derived longitudes of the principal and secondary temperature minima over time such that the magnetic structure appears to rotate somewhat more rapidly than the orbital period of this close binary. A sudden phase jump in the active region occurred between the observing seasons of 2001 and 2002. No clear trend over time is detected in the derived latitudes of the spots, indicating that the systematic motion could be related to the drift of the spot-generating mechanism rather than to differential rotation. The derived temperature maps are quite similar to the ones obtained earlier with different methods and the main differences occur in the spot latitudes and relative strength of the spot structures. Conclusions: We observe both longitude and latitude shifts in the spot activity of II Peg. However, our results are not consistent with the periodic behaviour presented in previous studies. Full Table 1 is only available in electronic form 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/526/A44

  5. STAR FORMATION HISTORIES IN A CLUSTER ENVIRONMENT AT z {approx} 0.84

    SciTech Connect

    Demarco, R.; Gobat, R.; Lidman, C.; Rettura, A.; Nonino, M.; Van der Wel, A.; Jee, M. J.; Blakeslee, J. P.; Ford, H. C.; Postman, M.

    2010-12-10

    We present a spectrophotometric analysis of galaxies belonging to the dynamically young, massive cluster RX J0152.7-1357 at z {approx} 0.84, aimed at understanding the effects of the cluster environment on the star formation history (SFH) of cluster galaxies and the assembly of the red sequence (RS). We use VLT/FORS spectroscopy, ACS/WFC optical, and NTT/SofI near-IR data to characterize SFHs as a function of color, luminosity, morphology, stellar mass, and local environment from a sample of 134 spectroscopic members. In order to increase the signal-to-noise ratio, individual galaxy spectra are stacked according to these properties. Moreover, the D4000, Balmer, CN3883, Fe4383, and C4668 indices are also quantified. The SFH analysis shows that galaxies in the blue faint-end of the RS have on average younger stars ({Delta}t {approx} 2 Gyr) than those in the red bright-end. We also found, for a given luminosity range, differences in age ({Delta}t {approx} 0.5-1.3 Gyr) as a function of color, indicating that the intrinsic scatter of the RS may be due to age variations. Passive galaxies in the blue faint-end of the RS are preferentially located in the low density areas of the cluster, likely being objects entering the RS from the 'blue cloud'. It is likely that the quenching of the star formation of these RS galaxies is due to interaction with the intracluster medium. Furthermore, the SFH of galaxies in the RS as a function of stellar mass reveals signatures of 'downsizing' in the overall cluster.

  6. O stars and Wolf-Rayet stars

    NASA Technical Reports Server (NTRS)

    Conti, Peter S.; Underhill, Anne B.; Jordan, Stuart (Editor); Thomas, Richard (Editor)

    1988-01-01

    Basic information is given about O and Wolf-Rayet stars indicating how these stars are defined and what their chief observable properties are. Part 2 of the volume discussed four related themes pertaining to the hottest and most luminous stars. Presented are: an observational overview of the spectroscopic classification and extrinsic properties of O and Wolf-Rayet stars; the intrinsic parameters of luminosity, effective temperature, mass, and composition of the stars, and a discussion of their viability; stellar wind properties; and the related issues concerning the efforts of stellar radiation and wind on the immediate interstellar environment are presented.

  7. Line profile asymmetries in chromospherically active stars

    NASA Technical Reports Server (NTRS)

    Dempsey, Robert C.; Bopp, Bernard W.; Strassmeier, Klaus G.; Granados, Arno F.; Henry, Gregory W.; Hall, Douglas S.

    1992-01-01

    A powerful, new probe of chromospheric activity, cross-correlation, has been developed and applied to a variety of stars. In this particular application, an entire CCD spectrum of an active star is correlated with the spectrum of a narrow-line, inactive star of similar spectral type and luminosity class. Using a number of strong lines in this manner enables the detection of absorption profile asymmetries at moderate resolution (lambda/Delta lambda about 40,000) and S/N 150:1. This technique has been applied to 14 systems mostly RS CVn's, with 10 not greater than nu sin i not greater than 50 km/s and P not less than 7 d. Distortions were detected for the first time in five systems: Sigma Gem, IM Peg, GX Lib, UV Crb, and Zeta And. Detailed modeling, incorporating both spectral line profiles and broad-band photometry, is applied to Sigma Gem. Profile asymmetries for this star are fitted by two high-latitude spots covering 5 percent of the stellar surface. The derived spot temperature of 3400 K is lower than found in previous studies. In addition, two well-known systems have been studied: HD 199178 and V711 Tau. Polar spots are found on both.

  8. Exceptional longevity and muscle and fitness related genotypes: a functional in vitro analysis and case-control association replication study with SNPs THRH rs7832552, IL6 rs1800795, and ACSL1 rs6552828

    PubMed Central

    Fuku, Noriyuki; He, Zi-hong; Sanchis-Gomar, Fabian; Pareja-Galeano, Helios; Tian, Ye; Arai, Yasumichi; Abe, Yukiko; Murakami, Haruka; Miyachi, Motohiko; Zempo, Hirofumi; Naito, Hisashi; Yvert, Thomas; Verde, Zoraida; Venturini, Letizia; Fiuza-Luces, Carmen; Santos-Lozano, Alejandro; Rodriguez-Romo, Gabriel; Ricevuti, Giovanni; Hirose, Nobuyoshi; Emanuele, Enzo; Garatachea, Nuria; Lucia, Alejandro

    2015-01-01

    There are several gene variants that are candidates to influence functional capacity in long-lived individuals. As such, their potential association with exceptional longevity (EL, i.e., reaching 100+ years) deserves analysis. Among them are rs7832552 in the thyrotropin-releasing hormone receptor (TRHR) gene, rs1800795 in the interleukin-6 (IL6) gene and rs6552828 in the coenzyme A synthetase long-chain 1 (ACSL1) gene. To gain insight into their functionality (which is yet unknown), here we determined for the first time luciferase gene reporter activity at the muscle tissue level in rs7832552 and rs6552828. We then compared allele/genotype frequencies of the 3 abovementioned variants among centenarians [n = 138, age range 100–111 years (114 women)] and healthy controls [n = 334, 20–50 years (141 women)] of the same ethnic and geographic origin (Spain). We also studied healthy centenarians [n = 79, 100–104 years (40 women)] and controls [n = 316, 27–81 years (156 women)] from Italy, and centenarians [n = 742, 100–116 years (623 women)] and healthy controls [n = 499, 23–59 years (356 women)] from Japan. The THRH rs7832552 T-allele and ACSL1 rs6552828 A-allele up-regulated luciferase activity compared to the C and G-allele, respectively (P = 0.001). Yet we found no significant association of EL with rs7832552, rs1800795 or rs6552828 in any of the 3 cohorts. Further research is needed with larger cohorts of centenarians of different origin as well as with younger old people. PMID:25999849

  9. Exceptional longevity and muscle and fitness related genotypes: a functional in vitro analysis and case-control association replication study with SNPs THRH rs7832552, IL6 rs1800795, and ACSL1 rs6552828.

    PubMed

    Fuku, Noriyuki; He, Zi-Hong; Sanchis-Gomar, Fabian; Pareja-Galeano, Helios; Tian, Ye; Arai, Yasumichi; Abe, Yukiko; Murakami, Haruka; Miyachi, Motohiko; Zempo, Hirofumi; Naito, Hisashi; Yvert, Thomas; Verde, Zoraida; Venturini, Letizia; Fiuza-Luces, Carmen; Santos-Lozano, Alejandro; Rodriguez-Romo, Gabriel; Ricevuti, Giovanni; Hirose, Nobuyoshi; Emanuele, Enzo; Garatachea, Nuria; Lucia, Alejandro

    2015-01-01

    There are several gene variants that are candidates to influence functional capacity in long-lived individuals. As such, their potential association with exceptional longevity (EL, i.e., reaching 100+ years) deserves analysis. Among them are rs7832552 in the thyrotropin-releasing hormone receptor (TRHR) gene, rs1800795 in the interleukin-6 (IL6) gene and rs6552828 in the coenzyme A synthetase long-chain 1 (ACSL1) gene. To gain insight into their functionality (which is yet unknown), here we determined for the first time luciferase gene reporter activity at the muscle tissue level in rs7832552 and rs6552828. We then compared allele/genotype frequencies of the 3 abovementioned variants among centenarians [n = 138, age range 100-111 years (114 women)] and healthy controls [n = 334, 20-50 years (141 women)] of the same ethnic and geographic origin (Spain). We also studied healthy centenarians [n = 79, 100-104 years (40 women)] and controls [n = 316, 27-81 years (156 women)] from Italy, and centenarians [n = 742, 100-116 years (623 women)] and healthy controls [n = 499, 23-59 years (356 women)] from Japan. The THRH rs7832552 T-allele and ACSL1 rs6552828 A-allele up-regulated luciferase activity compared to the C and G-allele, respectively (P = 0.001). Yet we found no significant association of EL with rs7832552, rs1800795 or rs6552828 in any of the 3 cohorts. Further research is needed with larger cohorts of centenarians of different origin as well as with younger old people. PMID:25999849

  10. Lifestyles of the Stars.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Cocoa Beach, FL. John F. Kennedy Space Center.

    Some general information on stars is provided in this National Aeronautics and Space Administration pamphlet. Topic areas briefly discussed are: (1) the birth of a star; (2) main sequence stars; (3) red giants; (4) white dwarfs; (5) neutron stars; (6) supernovae; (7) pulsars; and (8) black holes. (JN)

  11. Egyptian "Star Clocks"

    NASA Astrophysics Data System (ADS)

    Symons, Sarah

    Diagonal, transit, and Ramesside star clocks are tables of astronomical information occasionally found in ancient Egyptian temples, tombs, and papyri. The tables represent the motions of selected stars (decans and hour stars) throughout the Egyptian civil year. Analysis of star clocks leads to greater understanding of ancient Egyptian constellations, ritual astronomical activities, observational practices, and pharaonic chronology.

  12. CCD Echelle observations of the active RS CVn system II Pegasi

    NASA Astrophysics Data System (ADS)

    Huenemoerder, David P.; Ramsey, Lawrence W.

    1987-08-01

    Optical spectra were obtained of II Peg on eight different nights in 1984 and 1985 to assess the strength and variability of surface activity indicators in this very active RS CVn system. These cross-dispersed echelle spectra covered the range from 390 nm to 900 to 900 nm at a resolution of 12,000. EMission was seen in the first four Balmer lines, in the Ca II infrared triplet, Ca II H lines, and in one observation, in He I D3. The ratio of energy emitted in the H-alpha line to that in H-beta is similar to that in solar prominences, except during enhancements when the ratio decreases toward values more typical of solar flares. The H-alpha lines varied both in strength and in profile. There were slight variations in the Ca II infrared triplet lines. Exposure levels were too weak to assess the variations in H-gamma, H-delta, or Ca II H. Relative to comparison star spectra, the TiO bands at 896 nm and 710 nm were slightly deeper in II Peg, which is indicative of cool spots.

  13. The long-period RS CVn binary IM Pegasi --- II. First surface images

    NASA Astrophysics Data System (ADS)

    Berdyugina, S. V.; Berdyugin, A. V.; Ilyin, I.; Tuominen, I.

    2000-08-01

    New high-resolution, high signal-to-noise ratio spectroscopic observations and UBV photometry carried out in 1996-1999 were analysed with the surface imaging technique. A total of 8 images of IM Peg was obtained for the first time. A huge high-latitude active region was found to dominate the stellar surface and decreased in area during the period of the observations. At the same time, on the opposite hemisphere (in longitudes), smaller spots were developing. The spots were migrating in the orbital reference frame, the period of spot rotation being of 24.d73∓0.d02. The spots constitute two active longitudes on opposite stellar hemispheres, similar to other RS CVn stars. The evolution of the spot areas within the active longitudes indicates a stellar activity cycle, during which one active longitude dominates the stellar activity, to be about 6.5 years. Then, a total cycle, comprising two consecutive periods of activity of both active longitudes, is about 13 years. In 1999, the activity switched to the other active longitude. This declared the beginning of a new (half-) cycle. based on observations collected at the Nordic Optical Telescope (NOT), La Palma, Spain; the 2.6 m and 1.25 m telescopes of the Crimean Astrophysical Observatory, Ukraine; the 2m telescope of the National Astronomical Observatory, Rozhen, Bulgaria.

  14. Extragalactic Star Clusters: the Resolved Star Approach

    NASA Astrophysics Data System (ADS)

    Pellerin, Anne; Meyer, M. J.; Jason, H.; Calzetti, D.

    2006-12-01

    The physical processes leading to the dissolution of star clusters is a topic barely studied and still not understood. We started a pilot project to develop a new approach to directly detect and study the properties of stellar clusters while they are being destroyed. Our technique currently under development makes use of the exceptional spatial resolution and sensitivity of the ACS camera onboard HST to resolve individual stars in nearby galaxies. PSF stellar photometry and color-magnitude diagrams allows us to separate the most massive stars (more likely to be in clusters) from the star field background. While applying the method to the normal spiral galaxy NGC1313, we found that the method of studying star clusters through resolved stars in nearby galaxies is even more powerful than we first expected. The stellar maps obtained for NGC1313 show that a large fraction of early B-type stars contained in the galaxy are already part of the star field background rather that being in star clusters. Such stars live for 5 to 25 Myr. Since most stars form in clusters, the presence of such massive stars in the field means that they must have left their birthplace very rapidly. It also means that the processes involved in the dissolution of the clusters are extremely efficient. The only plausible explanation for so many young stars to be in the field background is the infant mortality of star clusters. We will present the latest results on the two galaxies NGC 1313 and IC 2475 and discuss the potential of the new approach for studying extragalactic stellar clusters.

  15. A non-LTE spectral analysis of the 3He and 4He isotopes in the HgMn star κ Cancri

    NASA Astrophysics Data System (ADS)

    Maza, Natalia L.; Nieva, María-Fernanda; Przybilla, Norbert

    2014-12-01

    Aims: We present a pilot study on non-local thermodynamic equilibrium (NLTE) line-formation computations for the isotopes 3He and 4He in the mercury-manganese star κ Cancri. The impact of NLTE effects on the determination of isotopic abundances and the vertical stratification of helium in the atmosphere is investigated. Methods: Modern NLTE line-formation computations were employed to analyse a high-resolution and high signal-to-noise ratio ESO-VLT/UVES spectrum of κ Cnc. The atmospheric parameters were determined from fitting the hydrogen Balmer lines and the spectral energy distribution. Multiple He i lines were investigated, including He i λ4921 Å and λ6678 Å, which show the widest isotopic splits. Results: Half of the observed He i lines in the spectrum of κ Cnc show significant NLTE strengthening, the effects are strongest in the red lines He iλ5875 Å and He iλ6678 Å. NLTE abundances from individual He i lines are up to a factor of ~3 lower than LTE values. Helium is found to be stratified in the atmosphere of κ Cnc. While the LTE analysis indicates a step-like profile of the helium abundance, a gradual decrease with height is indicated by the NLTE analysis. A 3He/4He ratio of ~0.25-0.30 is found. With the available data it cannot be decided whether the two isotopes follow the same stratification profile, or not. Conclusions: This work implies that NLTE effects may be ubiquitous in the atmospheres of HgMn stars and may have a significant impact on abundance determinations and the interpretation of the vertical abundance stratification of elements. Based on data products from observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 076.B-0055(A).Figures 3 and 4 are available in electronic form at http://www.aanda.org

  16. RS CVn binaries: Testing the solar-stellar dynamo connection

    NASA Technical Reports Server (NTRS)

    Dempsey, R.

    1995-01-01

    We have used the Extreme Ultraviolet Explorer satellite to study the coronal emission from the EUV-bright RS CVn binaries Sigma2 CrB, observed February 10-21, 1994, and II Peg, observed October 1-5, 1993. We present time-resolved and integrated EUV short-, medium-, and long-wavelength spectra for these binaries. Sigma2 CrB shows significant first-order emission features in the long-wavelength region. The coronal emission distributions and electron densities are estimated for those active coronae dominated by high temperature plasma.

  17. Neutron Stars and NuSTAR

    NASA Astrophysics Data System (ADS)

    Bhalerao, Varun

    2012-05-01

    My thesis centers around the study of neutron stars, especially those in massive binary systems. To this end, it has two distinct components: the observational study of neutron stars in massive binaries with a goal of measuring neutron star masses and participation in NuSTAR, the first imaging hard X-ray mission, one that is extremely well suited to the study of massive binaries and compact objects in our Galaxy. The Nuclear Spectroscopic Telescope Array (NuSTAR) is a NASA Small Explorer mission that will carry the first focusing high energy X-ray telescope to orbit. NuSTAR has an order-of-magnitude better angular resolution and has two orders of magnitude higher sensitivity than any currently orbiting hard X-ray telescope. I worked to develop, calibrate, and test CdZnTe detectors for NuSTAR. I describe the CdZnTe detectors in comprehensive detail here - from readout procedures to data analysis. Detailed calibration of detectors is necessary for analyzing astrophysical source data obtained by the NuSTAR. I discuss the design and implementation of an automated setup for calibrating flight detectors, followed by calibration procedures and results. Neutron stars are an excellent probe of fundamental physics. The maximum mass of a neutron star can put stringent constraints on the equation of state of matter at extreme pressures and densities. From an astrophysical perspective, there are several open questions in our understanding of neutron stars. What are the birth masses of neutron stars? How do they change in binary evolution? Are there multiple mechanisms for the formation of neutron stars? Measuring masses of neutron stars helps answer these questions. Neutron stars in high-mass X-ray binaries have masses close to their birth mass, providing an opportunity to disentangle the role of "nature" and "nurture" in the observed mass distributions. In 2006, masses had been measured for only six such objects, but this small sample showed the greatest diversity in masses among all classes of neutron star binaries. Intrigued by this diversity - which points to diverse birth masses - we undertook a systematic survey to measure the masses of neutron stars in nine high-mass X-ray binaries. In this thesis, I present results from this ongoing project. While neutron stars formed the primary focus of my work, I also explored other topics in compact objects. Appendix A describes the discovery and complete characterization of a 1RXS J173006.4+033813, a polar cataclysmic variable. Appendix B describes the discovery of a diamond planet orbiting a millisecond pulsar, and our search for its optical counterpart.

  18. Correlation between rs198388 and rs198389 polymorphismsin brainnatriuretic peptide (NPPB) gene and susceptibility to congenital heart diseases in a Chinese population

    PubMed Central

    Zhang, Qing; Gong, Fang-Qi; Zhu, Wei-Hua; Xie, Chun-Hong; Zhang, Yi-Ying; Ying, Li-Yang

    2015-01-01

    Objective: We discussed the correlation between SNP loci (rs198389 and rs198388) in brain natriuretic peptide gene (NPPB) and susceptibility to congenital heart diseases (CHD). Method: Multiplex SNaPshot technique was adopted for profiling of SNP genotypes at loci rs198389 and rs198388 in NPPB gene among 150 cases of CHDand 150 normal controls. Results: The distribution frequency of 3 genotypes (AA, AG and GG) at locus rs198389 was 40.7%, 36.0% and 23.3% in CHD group, respectively, showing significant differences compared with the normal controls (P<0.001). Gallele was associated with higher risk of CHD (OR=2.48, 95% CI=1.77-3.48). The distribution frequency of CC, CTand TT genotypes at locus rs198388 was 60.7%, 17.3% and 22.0% in CHD group, respectively, also showing significant differences compared with the normal controls (P<0.001). C allele could increase the risk of CHD (OR=1.92, 95% CI=1.48-2.48). Conclusion: SNP loci rs198389 and rs198388 in NPPB gene were correlated with genetic susceptibility to CHD. PMID:26770549

  19. Genome Sequencing of Ralstonia solanacearum Biovar 3, Phylotype I, Strains Rs-09-161 and Rs-10-244, Isolated from Eggplant and Chili in India

    PubMed Central

    Gaitonde, Sapna; Achari, Gauri; Asolkar, Trupti; Singh, Narendra Pratap; Carrere, Sebastien; Genin, Stephane; Peeters, Nemo

    2014-01-01

    Ralstonia solanacearum Indian strains Rs-09-161 and Rs-10-244 were isolated from the coastal region of Goa and from the Andaman Islands. We report the draft genome sequences of these representative isolates infecting solanaceous vegetables in India. PMID:24874667

  20. Chug and Dynamics of the RS-84 Subscale Preburner

    NASA Technical Reports Server (NTRS)

    Casiano, M. J; Morgan, C. J.; Scholten, N.

    2015-01-01

    The development of the RS-84 engine began in 2002 as part of the Space Launch Initiative. It was intended to be a reusable liquid oxygen/RP-1 booster engine of approximately 1 Mlbf thrust. Part of the test campaign consisted of testing subscale components to study key technologies such as oxygenrich, liquid oxygen/RP-1 combustion. In late 2003, the subscale preburner completed 4 hot-fire tests at Stennis Space Center with various hardware configurations and operating conditions, but before all planned tests could be completed the RS-84 engine development program was canceled in 2004. Recently, there has been a renewed interest in the development of an oxygen-rich, liquid oxygen/RP-1 combustion engine. Aerojet Rocketdyne and NASA completed testing of the subscale preburner in 2014 at Marshall Space Flight Center in an effort to better understand the chug encountered during the 2003 testing and to collect performance information over a wider range of operating conditions. The 2003 and 2014 data sets included extreme chug oscillations that reached nearly 200% of the chamber pressure and were reduced to well below 10% of the chamber pressure by incorporating a fuel orifice upstream of the fuel manifold. Depending on the hardware configuration and operating condition, a wide range of chug oscillation amplitudes were encountered. The dynamics for both test series were characterized and the data were used in the development of a chug model.

  1. VIIRS Aerosol Products During the SEAC4RS Field Experiment

    NASA Astrophysics Data System (ADS)

    Remer, L. A.; Munchak, L. A.; Huang, J.; Martins, J. V.; Espinosa, R.; Orozco, D.

    2014-12-01

    The Studies of Emissions, Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC4RS) field experiment that took place during August and September 2013 offered an in depth portrait of the aerosol system over much of the continental United States. Heavily instrumented aircraft, including the NASA DC-8 sampled a wide variety of aerosol types including transported Saharan dust, both fresh and aged smoke from western wildfires, urban pollution plumes and also biogenic aerosol produced by the "green volcano" in the vegetated Ozarks. Complementing these aircraft measurements was an enhanced array of AERONET stations sprinkled across the country and also concentrated in a mesoscale array near the home base of Houston Texas. This rich collection of suborbital aerosol information permits a more comprehensive evaluation of the VIIRS aerosol product that includes validation of the products across the mesoscale and choices of case studies in which we can delve deeper into the VIIRS retrieval to test algorithm assumptions. We will compare VIIRS retrievals during SEAC4RS with MODIS retrievals, with AERONET observations and retrievals, and with measurements and retrievals from the Polar Imaging Nephelometer (PI-Neph) that flew aboard the NASA DC-8.

  2. Association of polymorphisms hOGGI rs1052133 and hMUTYH rs3219472 with risk of nasopharyngeal carcinoma in a Chinese population

    PubMed Central

    Xie, Ying; Wu, Yuan; Zhou, Xunzhao; Yao, Mengwei; Ning, Sisi; Wei, Zhengbo

    2016-01-01

    This case–control study investigates the possible relationships between the single-nucleotide polymorphisms rs1052133 in the human 8-oxoguanine DNA glycosylase 1 (hOGG1) gene and rs3219472 in the human MutY glycosylase homologue (hMUTYH) gene and the risk of nasopharyngeal carcinoma (NPC). The two polymorphisms were genotyped in 488 unrelated NPC patients and 573 cancer-free controls. Genotype GG at rs1052133 was associated with significantly lower NPC risk than genotypes GC + CC (odds ratio [OR] 0.770, 95% confidence interval [CI] 0.595–0.996, P=0.012). In subgroup analyses, subjects with genotype GG at rs1052133 were at lower risk of NPC than those with GC or CC among individuals older than 40 years (OR 0.706, 95% CI 0.524–0.950), women (OR 0.571, 95% CI 0.337–0.968), and those with no smoking history (OR 0.634, 95% CI 0.463–0.868). No significant association was seen between polymorphisms at hMUTYH rs3219472 and the risk of NPC. However, gene–gene interaction analysis showed that subjects with genotype CC at rs1052133 and genotype AA at rs3219472 (CC/AA) were at 2.887-fold higher risk of NPC than those with GG/GG, 3.183-fold higher risk than those with GG/GA, and 3.392-fold higher risk than those with GG/AA. Our results suggest that hOGG1 rs1052133 polymorphism may play an important role in NPC pathogenesis, especially among women, >40 years old, and those with no smoking history. The hMUTYH rs3219472 polymorphism may interact with hOGG1 rs1052133 polymorphism to influence susceptibility to NPC. PMID:26929646

  3. First generation stars

    NASA Astrophysics Data System (ADS)

    Lu, Ye; Zhao, Gang; Liang, Yanchun

    2001-12-01

    The first generation stars mark the transition between the dark ages of the Universe and the appearance of the sky as we know it. Search for the first generation stars, (i.e., the population III stars, strictly with the chemical composition left by the Big Bang) has led to results that (1) No such stars were found, (2) Stars with metallicities significantly below [Fe/H] <= -2.5 were exceedingly rare. Owing to a recent survey undertaken by Beers, Preston and Shectman, the number of known extremely metal-poor stars in the Galaxy has substantially increased. At present, the lowest metallicity star ever has found [Fe/H] = -4.1. And the number of stars discovered with -4.0 <= [Fe/H] <= -3.0 is above 100. The kinematics of these stars is similar to that of other halo stars. The formation processes, the initial mass function of the first generation stars and their existence in the present universe are not known with any certainty. On the other hand, one thing is sure - they did exist! The first generation stars are enigmatic entity which challenges to astronomical observation and theory largely. One may wonder why no population III has been found if more than 100 stars known with metallicities from [Fe/H] = -4 to -3. Different kinds of explanations and observation programs have been proposed. In this paper, it is interesting to introduce some new progress about the first generation stars in the fields of the observation and theory.

  4. Creative Implementation of 3Rs Principles within Industry Programs: Beyond Regulations and Guidelines

    PubMed Central

    Bratcher, Natalie A; Reinhard, Gregory R

    2015-01-01

    The industry involved with using animals as an essential part of research has supported the theory and philosophy of the 3Rs for years. However, both the culture and approach surrounding the 3Rs is evolving rapidly, and many institutions are attempting to surpass the regulations and guidelines to implement the 3Rs for improved science and animal welfare. Regulatory documents and guidelines such as the Animal Welfare Act, the Guide for the Care and Use of Laboratory Animals, the Public Health Service Policy on Humane Care and Use of Laboratory Animals, and the US Government Principles for the Utilization and Care of Vertebrate Animals Used in Testing, Research, and Training clearly outline how the IACUC should address the 3Rs, but there are many additional paradigms and resources that an institution can use to promote the 3Rs creatively. We review the legal mandates and guidelines that institutions must or should follow, and we present some creative approaches toward their compliance, including the creation of full-time dedicated 3Rs roles as well as temporary 3Rs-focused positions such as visiting scientist and postdoctoral fellowships and internships. We also discuss how to creatively achieve 3Rs progress through internal committees and working groups, involvement in 3Rs consortia, recognizing 3Rs advances through awards programs, and creating 3Rs volunteer opportunities. Adherence to regulations and guidelines creates a solid foundation for good animal care and science, and creative 3Rs approaches enable the growth of a robust animal welfare culture that enhances the potential for 3Rs benefits to animals and science. PMID:25836958

  5. Creative implementation of 3Rs principles within industry programs: beyond regulations and guidelines.

    PubMed

    Bratcher, Natalie A; Reinhard, Gregory R

    2015-03-01

    The industry involved with using animals as an essential part of research has supported the theory and philosophy of the 3Rs for years. However, both the culture and approach surrounding the 3Rs is evolving rapidly, and many institutions are attempting to surpass the regulations and guidelines to implement the 3Rs for improved science and animal welfare. Regulatory documents and guidelines such as the Animal Welfare Act, the Guide for the Care and Use of Laboratory Animals, the Public Health Service Policy on Humane Care and Use of Laboratory Animals, and the US Government Principles for the Utilization and Care of Vertebrate Animals Used in Testing, Research, and Training clearly outline how the IACUC should address the 3Rs, but there are many additional paradigms and resources that an institution can use to promote the 3Rs creatively. We review the legal mandates and guidelines that institutions must or should follow, and we present some creative approaches toward their compliance, including the creation of full-time dedicated 3Rs roles as well as temporary 3Rs-focused positions such as visiting scientist and postdoctoral fellowships and internships. We also discuss how to creatively achieve 3Rs progress through internal committees and working groups, involvement in 3Rs consortia, recognizing 3Rs advances through awards programs, and creating 3Rs volunteer opportunities. Adherence to regulations and guidelines creates a solid foundation for good animal care and science, and creative 3Rs approaches enable the growth of a robust animal welfare culture that enhances the potential for 3Rs benefits to animals and science. PMID:25836958

  6. Effects of APOE rs429358, rs7412 and GSTM1/GSTT1 Polymorphism on Plasma and Erythrocyte Antioxidant Parameters and Cognition in Old Chinese Adults

    PubMed Central

    Yuan, Linhong; Liu, Jinmeng; Dong, Li; Cai, Can; Wang, Sisi; Wang, Bo; Xiao, Rong

    2015-01-01

    Apolipoprotein E (APOE) and oxidative damage were correlated with the risk of Alzheimer’s disease (AD). Glutathione S-transferase (GST) polymorphism was proved to be associated with body antioxidant capacity and involved in the oxidative damage related chronic diseases. To explore the combined effects of APOE rs429358, rs7412 and GSTM1/T1 polymorphism on antioxidant parameters and cognition in old Chinese adults, a community-based cross-sectional study was carried out in 477 Chinese adults aged from 55 to 75. Information on demography and lifestyle of the participants was collected with a questionnaire. Cognitive function was measured by using a Montreal Cognitive Assessment (MoCA) test. Fasting venous blood samples were collected for APOE rs429358, rs7412 and GSTM1/T1 genotyping, and parameter measurement. No association of APOE rs7412, rs429358 and GSTM1/T1 polymorphisms with cognition was detected in the old Chinese adults. APOE rs429358, rs7412 polymorphism was mainly associated with plasma α-tocopherol, low density lipoprotein cholesterol (LDL-C) and plasma total antioxidant capacity (T-AOC) levels (p < 0.05). Interaction of APOE rs429358 and GSTT1 genotype on the plasma triglyceride (TG) level and erythrocyte catalase (CAT) and GST enzyme activities were detected (p < 0.05). The subjects with APOE rs429358 T/C + C/C and GSTT1− genotype were found to have the highest plasma TG level, erythrocyte CAT enzyme activity, and the lowest GST enzyme activity compared to subjects with other genotypes (p < 0.05). Lowest erythrocyte CAT enzyme activity and highest glutathione peroxidase (GSH-Px) enzyme activity were detected in the subjects with APOE rs7412 T/C + T/T and GSTM1+ genotype as compared with subjects with other genotypes. The levels of plasma and erythrocyte antioxidant parameters were APOE genotype associated. GSTM1 or GSTT1 genotype modified the influence of APOE rs7412, rs429358 polymorphism on antioxidant parameters. PMID:26404360

  7. Effects of APOE rs429358, rs7412 and GSTM1/GSTT1 Polymorphism on Plasma and Erythrocyte Antioxidant Parameters and Cognition in Old Chinese Adults.

    PubMed

    Yuan, Linhong; Liu, Jinmeng; Dong, Li; Cai, Can; Wang, Sisi; Wang, Bo; Xiao, Rong

    2015-01-01

    Apolipoprotein E (APOE) and oxidative damage were correlated with the risk of Alzheimer's disease (AD). Glutathione S-transferase (GST) polymorphism was proved to be associated with body antioxidant capacity and involved in the oxidative damage related chronic diseases. To explore the combined effects of APOE rs429358, rs7412 and GSTM1/T1 polymorphism on antioxidant parameters and cognition in old Chinese adults, a community-based cross-sectional study was carried out in 477 Chinese adults aged from 55 to 75. Information on demography and lifestyle of the participants was collected with a questionnaire. Cognitive function was measured by using a Montreal Cognitive Assessment (MoCA) test. Fasting venous blood samples were collected for APOE rs429358, rs7412 and GSTM1/T1 genotyping, and parameter measurement. No association of APOE rs7412, rs429358 and GSTM1/T1 polymorphisms with cognition was detected in the old Chinese adults. APOE rs429358, rs7412 polymorphism was mainly associated with plasma α-tocopherol, low density lipoprotein cholesterol (LDL-C) and plasma total antioxidant capacity (T-AOC) levels (p < 0.05). Interaction of APOE rs429358 and GSTT1 genotype on the plasma triglyceride (TG) level and erythrocyte catalase (CAT) and GST enzyme activities were detected (p < 0.05). The subjects with APOE rs429358 T/C + C/C and GSTT1- genotype were found to have the highest plasma TG level, erythrocyte CAT enzyme activity, and the lowest GST enzyme activity compared to subjects with other genotypes (p < 0.05). Lowest erythrocyte CAT enzyme activity and highest glutathione peroxidase (GSH-Px) enzyme activity were detected in the subjects with APOE rs7412 T/C + T/T and GSTM1+ genotype as compared with subjects with other genotypes. The levels of plasma and erythrocyte antioxidant parameters were APOE genotype associated. GSTM1 or GSTT1 genotype modified the influence of APOE rs7412, rs429358 polymorphism on antioxidant parameters. PMID:26404360

  8. Novel Oversampling Technique for Improving Signal-to-Quantization Noise Ratio on Accelerometer-Based Smart Jerk Sensors in CNC Applications

    PubMed Central

    Rangel-Magdaleno, Jose J.; Romero-Troncoso, Rene J.; Osornio-Rios, Roque A.; Cabal-Yepez, Eduardo

    2009-01-01

    Jerk monitoring, defined as the first derivative of acceleration, has become a major issue in computerized numeric controlled (CNC) machines. Several works highlight the necessity of measuring jerk in a reliable way for improving production processes. Nowadays, the computation of jerk is done by finite differences of the acceleration signal, computed at the Nyquist rate, which leads to low signal-to-quantization noise ratio (SQNR) during the estimation. The novelty of this work is the development of a smart sensor for jerk monitoring from a standard accelerometer, which has improved SQNR. The proposal is based on oversampling techniques that give a better estimation of jerk than that produced by a Nyquist-rate differentiator. Simulations and experimental results are presented to show the overall methodology performance. PMID:22412337

  9. Novel Oversampling Technique for Improving Signal-to-Quantization Noise Ratio on Accelerometer-Based Smart Jerk Sensors in CNC Applications.

    PubMed

    Rangel-Magdaleno, Jose J; Romero-Troncoso, Rene J; Osornio-Rios, Roque A; Cabal-Yepez, Eduardo

    2009-01-01

    Jerk monitoring, defined as the first derivative of acceleration, has become a major issue in computerized numeric controlled (CNC) machines. Several works highlight the necessity of measuring jerk in a reliable way for improving production processes. Nowadays, the computation of jerk is done by finite differences of the acceleration signal, computed at the Nyquist rate, which leads to low signal-to-quantization noise ratio (SQNR) during the estimation. The novelty of this work is the development of a smart sensor for jerk monitoring from a standard accelerometer, which has improved SQNR. The proposal is based on oversampling techniques that give a better estimation of jerk than that produced by a Nyquist-rate differentiator. Simulations and experimental results are presented to show the overall methodology performance. PMID:22412337

  10. Massive Star Formation

    NASA Astrophysics Data System (ADS)

    Tan, J. C.; Beltrn, M. T.; Caselli, P.; Fontani, F.; Fuente, A.; Krumholz, M. R.; McKee, C. F.; Stolte, A.

    The enormous radiative and mechanical luminosities of massive stars impact a vast range of scales and processes, from the reionization of the universe, to the evolution of galaxies, to the regulation of the interstellar medium, to the formation of star clusters, and even to the formation of planets around stars in such clusters. Two main classes of massive star formation theory are under active study: core accretion and competitive accretion. In core accretion, the initial conditions are self-gravitating, centrally concentrated cores that condense with a range of masses from the surrounding, fragmenting clump environment. They then undergo relatively ordered collapse via a central disk to form a single star or a small-N multiple. In this case, the prestellar core mass function has a similar form to the stellar initial mass function. In competitive accretion, the material that forms a massive star is drawn more chaotically from a wider region of the clump without passing through a phase of being in a massive, coherent core. In this case, massive star formation must proceed hand in hand with star cluster formation. If stellar densities become very high near the cluster center, then collisions between stars may also help to form the most massive stars. We review recent theoretical and observational progress toward understanding massive star formation, considering physical and chemical processes, comparisons with low and intermediate-mass stars, and connections to star cluster formation.

  11. Detecting the Companions and Ellipsoidal Variations of RS CVn Primaries. II. o Draconis, a Candidate for Recent Low-mass Companion Ingestion

    NASA Astrophysics Data System (ADS)

    Roettenbacher, Rachael M.; Monnier, John D.; Fekel, Francis C.; Henry, Gregory W.; Korhonen, Heidi; Latham, David W.; Muterspaugh, Matthew W.; Williamson, Michael H.; Baron, Fabien; ten Brummelaar, Theo A.; Che, Xiao; Harmon, Robert O.; Schaefer, Gail H.; Scott, Nicholas J.; Sturmann, Judit; Sturmann, Laszlo; Turner, Nils H.

    2015-08-01

    To measure the stellar and orbital properties of the metal-poor RS CVn binary o Draconis (o Dra), we directly detect the companion using interferometric observations obtained with the Michigan InfraRed Combiner at Georgia State University's Center for High Angular Resolution Astronomy (CHARA) Array. The H-band flux ratio between the primary and secondary stars is the highest confirmed flux ratio (370 ± 40) observed with long-baseline optical interferometry. These detections are combined with radial velocity data of both the primary and secondary stars, including new data obtained with the Tillinghast Reflector Echelle Spectrograph on the Tillinghast Reflector at the Fred Lawrence Whipple Observatory and the 2 m Tennessee State University Automated Spectroscopic Telescope at Fairborn Observatory. We determine an orbit from which we find model-independent masses and ages of the components ({M}A=1.35+/- 0.05 {M}⊙ , {M}B=0.99+/- 0.02 {M}⊙ , system age = 3.0\\mp 0.5 Gyr). An average of a 23-year light curve of o Dra from the Tennessee State University Automated Photometric Telescope folded over the orbital period newly reveals eclipses and the quasi-sinusoidal signature of ellipsoidal variations. The modeled light curve for our system's stellar and orbital parameters confirm these ellipsoidal variations due to the primary star partially filling its Roche lobe potential, suggesting most of the photometric variations are not due to stellar activity (starspots). Measuring gravity darkening from the average light curve gives a best-fit of β =0.07+/- 0.03, a value consistent with conventional theory for convective envelope stars. The primary star also exhibits an anomalously short rotation period, which, when taken with other system parameters, suggests the star likely engulfed a low-mass companion that had recently spun-up the star.

  12. The Two-Component System CprRS Senses Cationic Peptides and Triggers Adaptive Resistance in Pseudomonas aeruginosa Independently of ParRS

    PubMed Central

    Fernández, Lucía; Jenssen, Håvard; Bains, Manjeet; Wiegand, Irith; Gooderham, W. James

    2012-01-01

    Cationic antimicrobial peptides pass across the outer membrane by interacting with negatively charged lipopolysaccharide (LPS), leading to outer membrane permeabilization in a process termed self-promoted uptake. Resistance can be mediated by the addition of positively charged arabinosamine through the action of the arnBCADTEF operon. We recently described a series of two-component regulators that lead to the activation of the arn operon after recognizing environmental signals, including low-Mg2+ (PhoPQ, PmrAB) or cationic (ParRS) peptides. However, some peptides did not activate the arn operon through ParRS. Here, we report the identification of a new two-component system, CprRS, which, upon exposure to a wide range of antimicrobial peptides, triggered the expression of the LPS modification operon. Thus, mutations in the cprRS operon blocked the induction of the arn operon in response to several antimicrobial peptides independently of ParRS but did not affect the response to low Mg2+. Distinct patterns of arn induction were identified. Thus, the responses to polymyxins were abrogated by either parR or cprR mutations, while responses to other peptides, including indolicidin, showed differential dependency on the CprRS and ParRS systems in a concentration-dependent manner. It was further demonstrated that, following exposure to inducing antimicrobial peptides, cprRS mutants did not become adaptively resistant to polymyxins as was observed for wild-type cells. Our microarray studies demonstrated that the CprRS system controlled a quite modest regulon, indicating that it was quite specific to adaptive peptide resistance. These findings provide greater insight into the complex regulation of LPS modification in Pseudomonas aeruginosa, which involves the participation of at least 4 two-component systems. PMID:23006746

  13. Incidence of RS virus infections in premature children's ward.

    PubMed

    Brůcková, M; Kunzová, L; Jezková, Z; Vocel, J

    1979-01-01

    In the course of two years (1974-76) four outbreaks of acute respiratory disease in the premature children's ward of a Prague hospital were studied virologically and clinically. RS virus (RSV) was found to be the aetiological agent. The highest isolation rate of RSV was achieved when using two heteroploid cell lines (L-132 and HEp-2 cells) simultaneously. Of the 30 children examined, 60% showed a severe course of disease (pneumonia and/or bronchiolitis) while in 40% of the children the disease had the form of rhinitis with striking abundance of whitish foamy secretions. In one of the outbreaks under study, two nurses with mild afebrile pharyngitis were detected as the source of RSV infection. PMID:575897

  14. Flaring on RS CVn systems: Results from EUVE Photometry

    NASA Astrophysics Data System (ADS)

    Osten, R. A.; Brown, A.; Ayres, T. R.

    We present broadband EUV photometry for a sample of RS CVn systems observed with the Deep Survey Spectrometer and Right Angle Program (RAP) Scanners on the Extreme Ultraviolet Explorer (EUVE). We have developed robust data analysis and light curve software for the interpretation of these data. Large-scale flaring activity is seen on 15 of the 18 systems studied. These binaries cover a range in orbital period of 0.7 days to 21 days and include a mixture of giant, subgiant, and dwarf luminosity classes. For many systems the photometric coverage extends over several orbital periods and flaring is unambiguously characterized. We present statistics on the distribution of variability in the survey. Correlations of flaring with binary properties are examined.

  15. HypoxamiRs and Cancer: From Biology to Targeted Therapy

    PubMed Central

    Gee, Harriet E.; Ivan, Cristina; Calin, George A.

    2014-01-01

    Abstract Significance: Hypoxia is a hallmark of the tumor microenvironment and represents a major source of failure in cancer therapy. Recent Advances: Recent work has generated extensive evidence that microRNAs (miRNAs) are significant components of the adaptive response to low oxygen in tumors. Induction of specific miRNAs, collectively termed hypoxamiRs, has become an accepted feature of the hypoxic response in normal and transformed cells. Critical Issues: Overexpression of miR-210, the prototypical hypoxamiR, is detected in most solid tumors, and it has been linked to adverse prognosis in many tumor types. Several miR-210 target genes, including iron-sulfur (Fe-S) cluster scaffold protein (ISCU) and glycerol-3-phosphate dehydrogenase 1-like (GPD1L), have been correlated with prognosis in an inverse fashion to miR-210, suggesting that their down- regulation by miR-210 occurs in vivo and contributes to tumor growth. Additional miRNAs are modulated by decreased oxygen tension in a more tissue-specific fashion, adding another level of complexity over the classic hypoxia-regulated gene network. Future Directions: From a biological standpoint, hypoxamiRs are emerging modifiers of cancer cell response to the adaptive challenges of the microenvironment. From a clinical perspective, assessing the status of these miRNAs may contribute to a detailed understanding of hypoxia-induced mechanisms of resistance and/or to the fine-tuning of future hypoxia-modifying therapies. Antioxid. Redox Signal. 21, 1220–1238. PMID:24111776

  16. Star Formation in Galaxies

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Topics addressed include: star formation; galactic infrared emission; molecular clouds; OB star luminosity; dust grains; IRAS observations; galactic disks; stellar formation in Magellanic clouds; irregular galaxies; spiral galaxies; starbursts; morphology of galactic centers; and far-infrared observations.

  17. Astrophysics: Stars fight back

    NASA Astrophysics Data System (ADS)

    Hopkins, Philip F.

    2014-12-01

    Galaxies contain fewer stars than predicted. The discovery of a massive galactic outflow of molecular gas in a compact galaxy, which forms stars 100 times faster than the Milky Way, may help to explain why. See Letter p.68

  18. Intrinsically variable stars

    NASA Technical Reports Server (NTRS)

    Bohm-Vitense, Erika; Querci, Monique

    1987-01-01

    The characteristics of intrinsically variable stars are examined, reviewing the results of observations obtained with the IUE satellite since its launch in 1978. Selected data on both medium-spectral-class pulsating stars (Delta Cep stars, W Vir stars, and related groups) and late-type variables (M, S, and C giants and supergiants) are presented in spectra, graphs, and tables and described in detail. Topics addressed include the calibration of the the period-luminosity relation, Cepheid distance determination, checking stellar evolution theory by the giant companions of Cepheids, Cepheid masses, the importance of the hydrogen convection zone in Cepheids, temperature and abundance estimates for Population II pulsating stars, mass loss in Population II Cepheids, SWP and LWP images of cold giants and supergiants, temporal variations in the UV lines of cold stars, C-rich cold stars, and cold stars with highly ionized emission lines.

  19. The Obesity-Associated Polymorphisms FTO rs9939609 and MC4R rs17782313 and Endometrial Cancer Risk in Non-Hispanic White Women

    PubMed Central

    Lurie, Galina; Gaudet, Mia M.; Spurdle, Amanda B.; Carney, Michael E.; Wilkens, Lynne R.; Yang, Hannah P.; Weiss, Noel S.; Webb, Penelope M.; Thompson, Pamela J.; Terada, Keith; Setiawan, Veronica Wendy; Rebbeck, Timothy R.; Prescott, Jennifer; Orlow, Irene; O'Mara, Tracy; Olson, Sara H.; Narod, Steven A.; Matsuno, Rayna K.; Lissowska, Jolanta; Liang, Xiaolin; Levine, Douglas A.; Le Marchand, Loic; Kolonel, Laurence N.; Henderson, Brian E.; Garcia-Closas, Montserrat; Doherty, Jennifer Anne; De Vivo, Immaculata; Chen, Chu; Brinton, Louise A.; Akbari, Mohammad R.; Goodman, Marc T.

    2011-01-01

    Overweight and obesity are strongly associated with endometrial cancer. Several independent genome-wide association studies recently identified two common polymorphisms, FTO rs9939609 and MC4R rs17782313, that are linked to increased body weight and obesity. We examined the association of FTO rs9939609 and MC4R rs17782313 with endometrial cancer risk in a pooled analysis of nine case-control studies within the Epidemiology of Endometrial Cancer Consortium (E2C2). This analysis included 3601 non-Hispanic white women with histologically-confirmed endometrial carcinoma and 5275 frequency-matched controls. Unconditional logistic regression models were used to assess the relation of FTO rs9939609 and MC4R rs17782313 genotypes to the risk of endometrial cancer. Among control women, both the FTO rs9939609 A and MC4R rs17782313 C alleles were associated with a 16% increased risk of being overweight (p = 0.001 and p = 0.004, respectively). In case-control analyses, carriers of the FTO rs9939609 AA genotype were at increased risk of endometrial carcinoma compared to women with the TT genotype [odds ratio (OR)  = 1.17; 95% confidence interval (CI): 1.03–1.32, p = 0.01]. However, this association was no longer apparent after adjusting for body mass index (BMI), suggesting mediation of the gene-disease effect through body weight. The MC4R rs17782313 polymorphism was not related to endometrial cancer risk (per allele OR = 0.98; 95% CI: 0.91–1.06; p = 0.68). FTO rs9939609 is a susceptibility marker for white non-Hispanic women at higher risk of endometrial cancer. Although FTO rs9939609 alone might have limited clinical or public health significance for identifying women at high risk for endometrial cancer beyond that of excess body weight, further investigation of obesity-related genetic markers might help to identify the pathways that influence endometrial carcinogenesis. PMID:21347432

  20. Chromospheres of Coronal Stars

    NASA Technical Reports Server (NTRS)

    Linsky, Jeffrey L.; Wood, Brian E.

    1996-01-01

    We summarize the main results obtained from the analysis of ultraviolet emission line profiles of coronal late-type stars observed with the Goddard High Resolution Spectrograph (GHRS) on the Hubble Space Telescope. The excellent GHRS spectra provide new information on magnetohydrodynamic phenomena in the chromospheres and transition regions of these stars. One exciting new result is the discovery of broad components in the transition region lines of active stars that we believe provide evidence for microflare heating in these stars.

  1. Dibaryons in neutron stars

    NASA Technical Reports Server (NTRS)

    Olinto, Angela V.; Haensel, Pawel; Frieman, Joshua A.

    1991-01-01

    The effects are studied of H-dibaryons on the structure of neutron stars. It was found that H particles could be present in neutron stars for a wide range of dibaryon masses. The appearance of dibaryons softens the equations of state, lowers the maximum neutron star mass, and affects the transport properties of dense matter. The parameter space is constrained for dibaryons by requiring that a 1.44 solar mass neutron star be gravitationally stable.

  2. ChemLabBox for SnifferStars

    Energy Science and Technology Software Center (ESTSC)

    2002-01-24

    The software entitled "ChemLabBox for SnifferStars" is used to collect, display, and save data from the Sandia National Laboratories chemical analysis system dubbed SnifferStar. Sensor data is streamed from a SnifferStar unit into a computer thru RS-232 in a manner that is not amendable to plotting. Also, there is no direct way to start and stop the unit as is. This software rearranges the data into something that can be easily plotted in real-time thenmore » saves the data into a text fild. In addition, this software provides the users a means to start and stop the hardware. This software was written specifically for SnifferStar. SnifferStar data is delivered at a very fast rate but for a short period of time. This software is written around that premise. It is written for Pentium or higher machines running Windows 95/98/ME/NT/2000/XP. Lockheed Martin is interested in using it for testing SnifferStar units before deployment. To date they have not indicated their intent to deliver the code either in part or whole as part of their product.« less

  3. Chromospheric activity and rotational modulation of the RS Canum Venaticorum binary V711 Tauri during 1998-2004

    NASA Astrophysics Data System (ADS)

    Cao, Dongtao; Gu, Shenghong

    2015-05-01

    We present long-term high-resolution spectroscopic observations of the very active RS Canum Venaticorum-type star V711 Tau, obtained during several observing runs from 1998 to 2004, and study its chromospheric activity. Using the spectral subtraction technique, several optical chromospheric activity indicators [including the He I D3, Na I D1, D2, Hα and Ca II infrared triplet (IRT) lines] formed at different atmospheric heights are analysed. Strong chromospheric emission supports earlier results that indicate that V711 Tau is a very active system. Two large optical flares were detected during our observations. The results suggest that the main part of chromospheric emission is attributed to the primary star of the system. The secondary also presents weak emission but is less active. The ratios of EW8542/EW8498 indicate that Ca II IRT emission arises predominantly from plage-like regions. We have found rotational modulation of chromospheric activity in the Hα and Ca II IRT lines, which suggests the presence of the chromospheric active longitudes over the surface of V711 Tau. Two active longitudes separated by about 180° were observed to dominate the activity, and the so-called flip-flop phenomenon was seen during our observations. Moreover, the chromospheric activity level shows a long-term variation that gradually increases from a deep minimum near the year 2002. A close spatial connection of photospheric spots and chromospheric active regions in both short and long timescales was found for V711 Tau.

  4. A pre-outburst signal in the long-term optical light curve of the recurrent nova RS Ophiuchi

    NASA Astrophysics Data System (ADS)

    Adamakis, S.; Eyres, S. P. S.; Sarkar, A.; Walsh, R. W.

    2011-07-01

    Recurrent novae are binary stars in which a white dwarf accretes matter from a less evolved companion, either a red giant or a main-sequence star. They have dramatic optical brightenings of around 5-6 mag in V in less than a day, several times a century. These occur at variable and unpredictable intervals, and are followed by an optical decline over several weeks and activity from the X-ray to the radio. The unpredictability of recurrent novae and related stellar types can hamper systematic study of their outbursts. Here we analyse the long-term light curve of RS Ophiuchi, a recurrent nova with six confirmed outbursts, most recently in 2006 February. We confirm the previously suspected 1945 outburst, largely obscured in a seasonal gap. We also find a signal via wavelet analysis that can be used to predict an incipient outburst up to a few hundred days before hand. This has never before been possible. In addition, this may suggest that the preferred thermonuclear runaway mechanism for the outbursts will have to be modified, as no pre-outburst signal is anticipated in that case. If our result indeed points to gaps in our understanding of how outbursts are driven, we will need to study such objects carefully to determine if the white dwarf is growing in mass, an essential factor if these systems are to become Type Ia supernovae. Determining the likelihood of recurrent novae being an important source population will have implications for stellar and galaxy evolution.

  5. A study of X-ray emission from Ap and Am stars

    NASA Technical Reports Server (NTRS)

    Cash, W.; Snow, T. P., Jr.

    1982-01-01

    Twenty stars classified as either Ap or Am have been imaged by the Imaging Proportional Counter on the Einstein Observatory in a search for evidence of coronal emission. It is found that an Am star will not be a source (at the 10 to the 28th ergs/sec level) unless it is in a spectroscopic binary with a period below about 10 days. The X-rays in the close binaries can be explained by the RS CVn effect in the late-type secondary, and the evidence is against strong emission from Am stars. Among the nine Ap stars observed, four were detected. While it is possible that the X-rays are being generated by undetected late-type dwarf companions, the large fraction of detections makes the Ap stars themselves the likely source of emission.

  6. Spots on Am stars

    NASA Astrophysics Data System (ADS)

    Balona, L. A.; Catanzaro, G.; Abedigamba, O. P.; Ripepi, V.; Smalley, B.

    2015-04-01

    We investigate the light variations of 15 Am stars using four years of high-precision photometry from the Kepler spacecraft and an additional 14 Am stars from the K2 Campaign 0 field. We find that most of the Am stars in the Kepler field have light curves characteristic of rotational modulation due to star-spots. Of the 29 Am stars observed, 12 are ? Scuti variables and one is a ? Doradus star. One star is an eclipsing binary and another was found to be a binary from time delay measurements. Two Am stars show evidence for flares which are unlikely to be due to a cool companion. The fact that 10 out of 29 Am stars are rotational variables and that some may even flare strongly suggests that Am stars possess significant magnetic fields. This is contrary to the current understanding that the enhanced metallicity in these stars is due to diffusion in the absence of a magnetic field. The fact that so many stars are ? Scuti variables is also at odds with the prediction of diffusion theory. We suggest that a viable alternative is that the metal enhancement could arise from accretion.

  7. America's Star Libraries

    ERIC Educational Resources Information Center

    Lyons, Ray; Lance, Keith Curry

    2009-01-01

    "Library Journal"'s new national rating of public libraries, the "LJ" Index of Public Library Service, identifies 256 "star" libraries. It rates 7,115 public libraries. The top libraries in each group get five, four, or three Michelin guide-like stars. All included libraries, stars or not, can use their scores to learn from their peers and improve…

  8. America's Star Libraries

    ERIC Educational Resources Information Center

    Lyons, Ray; Lance, Keith Curry

    2009-01-01

    "Library Journal"'s new national rating of public libraries, the "LJ" Index of Public Library Service, identifies 256 "star" libraries. It rates 7,115 public libraries. The top libraries in each group get five, four, or three Michelin guide-like stars. All included libraries, stars or not, can use their scores to learn from their peers and improve

  9. Managing the star performer.

    PubMed

    Hills, Laura

    2013-01-01

    Our culture seems to be endlessly fascinated with its stars in entertainment, athletics, politics, and business, and holds fast to the idea that extraordinary talent accounts for an individual's extraordinary performance. At first glance, managing a star performer in your medical practice may seem like it would be an easy task. However, there's much more to managing a star performer than many practice managers realize. The concern is how to keep the star performer happy and functioning at a high level without detriment to the rest of the medical practice team. This article offers tips for practice managers who manage star performers. It explores ways to keep the star performer motivated, while at the same time helping the star performer to meld into the existing medical practice team. This article suggests strategies for redefining the star performer's role, for holding the star performer accountable for his or her behavior, and for coaching the star performer. Finally, this article offers practical tips for keeping the star performer during trying times, for identifying and cultivating new star performers, and for managing medical practice prima donnas. PMID:23767124

  10. Composite spectra: XX. 45 Cancri. Two stars with very similar masses but quite different evolutionary states

    NASA Astrophysics Data System (ADS)

    Griffin, R. E. M.; Griffin, R. F.

    2015-02-01

    From accurate radial-velocity measurements covering 11 circuits of the orbit of the composite-spectrum binary 45 Cnc, together with high-resolution spectroscopy spanning nearly 3 circuits, we have (i) isolated cleanly the spectrum of the early-type secondary, (ii) classified the component spectra as G8 III and A3 III, (iii) derived the first double-lined orbit for the system and a mass ratio (M_1/M_2) of 1.035 0.01, and (iv) extracted physical parameters for the component stars, deriving the masses and (log) luminosities of the G star and A star as 3.11 and 3.00 M?} R?, and 2.34 and 2.28 L?, respectively, with corresponding uncertainties of 0.10 M? R? and 0.09 L?. Since the mass ratio is close to unity, we argue that the more evolved component is unlikely to have been a red giant long enough to have made multiple ascents of the RGB, an argument that is supported somewhat by the rather high eccentricity of the orbit (e = 0.46) and the evolutionary time-scales of the two components, but chiefly by the presence of significant Li I in the spectrum of the cool giant.

  11. Identification and frequency of the rs12516 and rs8176318 BRCA1 gene polymorphisms among different populations

    PubMed Central

    YANG, FANG; CHEN, FENGXIA; XU, JIN; GUAN, XIAOXIANG

    2016-01-01

    Genetic mutation of breast cancer 1 (BRCA1) is one of the most notable factors responsible for a proportion of breast cancer cases. BRCA1 encodes a 1,863-amino acid protein and functions as a negative regulator of tumor growth. Thus, investigation of the underlying mechanisms that regulate BRCA1 gene expression provide further insight into possible targets for breast cancer therapy. Previous studies have demonstrated that the genetic variants in the BRCA1 3′ untranslated region (3′UTR), in addition to the cytosine-phosphate-guanine (CpG) islands in the promoter region, are significantly associated with breast cancer risk; however, the role of single nucleotide polymorphisms (SNPs) in the BRCA1 3′UTR remains unclear. The present study aimed to investigate the association between SNPs and BRCA1 mRNA expression levels. Bioinformatics analysis demonstrated that 2 SNPs in the BRCA1 3′UTR (rs12516 and rs8176318 with putative microRNA binding sites) were significantly correlated with mRNA expression in lymphoblastoid cell lines (P=2.55×10-4 and P=8.78×10−5, respectively). Furthermore, the genotype frequency distribution varied between populations worldwide. In addition, 3 CpG islands and several transcription factor binding sites in the BRCA1 promoter region were established. The identification of such polymorphisms and CpG islands may aid in designing improved therapeutic strategies to treat patients with BRCA1-associated breast cancer. PMID:27073502

  12. Detecting the Companions and Ellipsoidal Variations of RS CVn Primaries. I. σ Geminorum

    NASA Astrophysics Data System (ADS)

    Roettenbacher, Rachael M.; Monnier, John D.; Henry, Gregory W.; Fekel, Francis C.; Williamson, Michael H.; Pourbaix, Dimitri; Latham, David W.; Latham, Christian A.; Torres, Guillermo; Baron, Fabien; Che, Xiao; Kraus, Stefan; Schaefer, Gail H.; Aarnio, Alicia N.; Korhonen, Heidi; Harmon, Robert O.; ten Brummelaar, Theo A.; Sturmann, Judit; Sturmann, Laszlo; Turner, Nils H.

    2015-07-01

    To measure the properties of both components of the RS Canum Venaticorum binary σ Geminorum (σ Gem), we directly detect the faint companion, measure the orbit, obtain model-independent masses and evolutionary histories, detect ellipsoidal variations of the primary caused by the gravity of the companion, and measure gravity darkening. We detect the companion with interferometric observations obtained with the Michigan InfraRed Combiner at Georgia State University’s Center for High Angular Resolution Astronomy Array with a primary-to-secondary H-band flux ratio of 270 ± 70. A radial velocity curve of the companion was obtained with spectra from the Tillinghast Reflector Echelle Spectrograph on the 1.5 m Tillinghast Reflector at Fred Lawrence Whipple Observatory. We additionally use new observations from the Tennessee State University Automated Spectroscopic and Photometric Telescopes (AST and APT, respectively). From our orbit, we determine model-independent masses of the components ({M}1=1.28+/- 0.07 {M}⊙ , {M}2=0.73+/- 0.03 {M}⊙ ), and estimate a system age of 5∓ 1 Gyr. An average of the 27 year APT light curve of σ Gem folded over the orbital period (P=19.6027+/- 0.0005 days) reveals a quasi-sinusoidal signature, which has previously been attributed to active longitudes 180° apart on the surface of σ Gem. With the component masses, diameters, and orbit, we find that the predicted light curve for ellipsoidal variations due to the primary star partially filling its Roche lobe potential matches well with the observed average light curve, offering a compelling alternative explanation to the active longitudes hypothesis. Measuring gravity darkening from the light curve gives β <; 0.1, a value slightly lower than that expected from recent theory.

  13. A Combination of CD28 (rs1980422) and IRF5 (rs10488631) Polymorphisms Is Associated with Seropositivity in Rheumatoid Arthritis: A Case Control Study

    PubMed Central

    Spoutil, Frantisek; Vlcek, Miroslav; Krskova, Katarina; Penesova, Adela; Meskova, Milada; Marko, Andrea; Raslova, Katarina; Vohnout, Branislav; Rovensky, Jozef; Killinger, Zdenko; Jochmanova, Ivana; Lazurova, Ivica; Steiner, Guenter; Smolen, Josef; Imrich, Richard

    2016-01-01

    Introduction The aim of the study was to analyse genetic architecture of RA by utilizing multiparametric statistical methods such as linear discriminant analysis (LDA) and redundancy analysis (RDA). Methods A total of 1393 volunteers, 499 patients with RA and 894 healthy controls were included in the study. The presence of shared epitope (SE) in HLA-DRB1 and 11 SNPs (PTPN22 C/T (rs2476601), STAT4 G/T (rs7574865), CTLA4 A/G (rs3087243), TRAF1/C5 A/G (rs3761847), IRF5 T/C (rs10488631), TNFAIP3 C/T (rs5029937), AFF3 A/T (rs11676922), PADI4 C/T (rs2240340), CD28 T/C (rs1980422), CSK G/A (rs34933034) and FCGR3A A/C (rs396991), rheumatoid factor (RF), anti–citrullinated protein antibodies (ACPA) and clinical status was analysed using the LDA and RDA. Results HLA-DRB1, PTPN22, STAT4, IRF5 and PADI4 significantly discriminated between RA patients and healthy controls in LDA. The correlation between RA diagnosis and the explanatory variables in the model was 0.328 (Trace = 0.107; F = 13.715; P = 0.0002). The risk variants of IRF5 and CD28 genes were found to be common determinants for seropositivity in RDA, while positivity of RF alone was associated with the CTLA4 risk variant in heterozygous form. The correlation between serologic status and genetic determinants on the 1st ordinal axis was 0.468, and 0.145 on the 2nd one (Trace = 0.179; F = 6.135; P = 0.001). The risk alleles in AFF3 gene together with the presence of ACPA were associated with higher clinical severity of RA. Conclusions The association among multiple risk variants related to T cell receptor signalling with seropositivity may play an important role in distinct clinical phenotypes of RA. Our study demonstrates that multiparametric analyses represent a powerful tool for investigation of mutual relationships of potential risk factors in complex diseases such as RA. PMID:27092776

  14. Association between rs7517847 and rs2201841 polymorphisms in IL-23 receptor gene and risk of ankylosing spondylitis: a meta-analysis

    PubMed Central

    Xu, Bin; Ma, Jian-xiong; Jia, Hao-bo; Feng, Rui; Xu, Li-yan

    2015-01-01

    To comprehensively evaluate the association between rs7517847 and rs2201841 polymorphisms in the Interleukin-23 (IL-23) receptor gene and ankylosing spondylitis (AS), a meta-analysis was performed. The Pubmed, Embase, MEDLINE, Cochrane, China National Knowledge Infrastructure (CNKI), VIP, Wanfang and China Biology Medicine disc (CBMdisc) databases were searched to identify eligible studies on rs7517847 and rs2201841 polymorphisms in the IL-23 receptor gene and AS that were published through September 2014. Data of interest were extracted from each study, and the meta-analysis was performed using STATA 12.0. Four studies were eligible for the meta-analysis and included a total patient population of 2,465. With regards to rs7517847, the current study showed that the genotype GG and allele G might play a protective role during AS (OR = 0.76, 95% CI [0.59–0.99]; OR = 0.88, 95% CI [0.78–0.99] for homozygote and allelic models, respectively). However, according to the meta-analysis, there was no statistical association between the genotype or allele of rs2201841 and an individual’s susceptibility to AS in all genetic models. In conclusion, it was the IL-23 rs7517847 polymorphism rather than the rs2201841 polymorphism that had a statistical association with AS. Nevertheless, more evidence is needed to confirm this result. Consequently, it is necessary to carry out more high-quality studies to confirm the associations between these two single nucleotide polymorphisms and AS. PMID:25922796

  15. Associations between two single-nucleotide polymorphisms (rs1801278 and rs2943641) of insulin receptor substrate 1 gene and type 2 diabetes susceptibility: a meta-analysis.

    PubMed

    Li, Qiuyan; Qiao, Yuandong; Wang, Chuntao; Zhang, Guangfa; Zhang, Xuelong; Xu, Lidan

    2016-01-01

    The objective of the study is to assess the association between rs1801278 and rs2943641 of insulin receptor substrate 1 gene (IRS1) and the susceptibility to type 2 diabetes. A literature search strategy was conducted to identify all references lists of relevant studies. The fixed or random effect model was used to calculate the pooled ORs on the basis of heterogeneity. Further analyses were performed to explore the sources of heterogeneity by sensitivity analysis, meta-regression analysis, and subgroup analysis. There was significant association between rs1801278 and type 2 diabetes risk in recessive model (AA vs. GA + GG, p = 0.043) and codominant model (AA vs. GG, p = 0.007). Subgroup analysis showed that the association between rs1801278 and type 2 diabetes risk was significant in dominant model (GA + AA vs. GG, p = 0.044), codominant model (GA vs. GG, p = 0.039), codominant model (AA vs. GG, p = 0.044), overdominant model (GG + AA vs. GA, p = 0.037) in Asian and codominant model (AA vs. GG, p = 0.039) in Caucasian of rs1801278. The association between rs2943641 and type 2 diabetes risk was significant in codominant model (CT vs. CC, p = 0.023) in Caucasian. This meta-analysis suggests that rs1801278 may play a role in type 2 diabetes risk, especially in Asian. It also indicates that rs2943641 may be associated with type 2 diabetes risk in Caucasian. Further larger studies should be performed to warrant confirmation. PMID:26582067

  16. No relationship between most polymorphisms of steroidogenic acute regulatory (StAR) gene with polycystic ovarian syndrome

    PubMed Central

    Nazouri, Azadeh-Sadat; Khosravifar, Mona; Akhlaghi, Ali-Asghar; Shiva, Marzieh; Afsharian, Parvaneh

    2015-01-01

    Background: Polycystic ovary syndrome (PCOS) is one of the most common endocrine women’s disorders in reproductive age. Hyperandrogenism has a critical role in the etiology of PCOS and it can cause fault in Steroidogenesis process. During steroidogenesis, steroidogenic acute regulatory protein (StAR) seems to increase the delivery of cholesterol through mitochondrial membrane. Therefore, polymorphisms of StAR might effect on this protein and play a role in the etiology of PCOS. Objective: The aim of this study was to investigate the association between StAR SNPs with PCOS. Thus, seven polymorphisms in this gene: rs104894086, rs104894089, rs104894090, rs137852689, rs10489487, rs104894085 were detected. Materials and Methods: In this case control study, 45 PCOS women, 40 male factor/unexplained infertile women, and 40 fertile women as two control groups were participated from 2008-2012. Polymorphisms were detected using restriction fragment length polymorphism (PCR-RFLP) method. Results: Heterozygote genotyping for rs137852689 SNP (amino acid 218 C > T) was only seen in seven PCOS patients, one in normal ovulatory women, and five in male factor/unexplained infertile women (15.5%, 2.5%, 12.5%, respectively) (p= 0.12). While, it has shown no association between other SNPS with PCOs. Conclusion: The RFLP results for seven chosen SNPs, which located in exon 5 and 7 showed normal status in three groups, it means no heterozygous or homozygous forms of selected SNPs were observed. So, it seems evaluation of the active amino acid sites should be investigated and also the study population should be increased. PMID:27141537

  17. Polymorphisms in TRPV1 and TAS2Rs associate with sensations from sampled ethanol

    PubMed Central

    Allen, Alissa L.; McGeary, John E.; Hayes, John E.

    2014-01-01

    Background Genetic variation in chemosensory genes can explain variability in individual’s perception of and preference for many foods and beverages. To gain insight into variable preference and intake of alcoholic beverages, we explored individual variability in the responses to sampled ethanol. In humans, ethanol elicits sweet, bitter and burning sensations. Here, we explore the relationship between variation in ethanol sensations and polymorphisms in genes encoding bitter taste receptors (TAS2Rs) and a polymodal nociceptor (TRPV1). Methods Caucasian participants (n=93) were genotyped for 16 SNPs in TRPV1, 3 SNPs in TAS2R38 and 1 SNP in TAS2R13. Participants rated sampled ethanol on a generalized Labeled Magnitude Scale. Two stimuli were presented: a 16% ethanol whole mouth sip-and-spit solution with a single time-point rating of overall intensity, and a cotton swab saturated with 50% ethanol on the circumvallate papillae (CV) with repeated ratings made over 3 minutes. Area under the curve (AUC) was calculated for the time-intensity data. Results The ethanol whole mouth solution had overall intensity ratings near ‘very strong’. Burning/stinging had the highest mean AUC values, followed by bitterness and sweetness. Whole mouth intensity ratings were significantly associated with burning/stinging and bitterness AUC values on the CV. Three TRPV1 SNPs (rs224547, rs4780521, rs161364) were associated with ethanol sensations on the CV, with two (rs224547 and rs4780521) exhibiting strong linkage disequilibrium. Additionally, the TAS2R38 SNPs rs713598, rs1726866, and rs10246939 formed a haplotype, and were associated with bitterness on the CV. Lastly, overall intensity for whole mouth ethanol associated with the TAS2R13 SNP rs1015443. Conclusions These data suggest genetic variations in TRPV1 and TAS2Rs influence sensations from sampled ethanol and may potentially influence how individuals initially respond to alcoholic beverages. PMID:25257701

  18. NEDD4 single nucleotide polymorphism rs2271289 is associated with keloids in Chinese Han population

    PubMed Central

    Zhao, Ying; Liu, Sheng-Li; Xie, Jian; Ding, Mao-Qian; Lu, Meng-Zhu; Zhang, Lan-Fang; Yao, Xiu-Hua; Hu, Bai; Lu, Wen-Sheng; Zheng, Xiao-Dong

    2016-01-01

    Keloids are abnormally raised fibroproliferative lesions that usually occur following cutaneous traumas. Recently, a large-scale genome-wide association study (GWAS) has identified multiple single nucleotide polymorphisms (SNPs) in three genetic loci that are associated with keloids in Japanese population. Subsequently, two reported loci 1q41 (rs873549 and rs1442440) and 15q21.3 (rs2271289) for keloids were confirmed in selected Chinese population. The association of these SNPs with clinical features of keloids, has not yet been studied. To explore the role of these SNPs in the pathogenesis of keloids, we performed a case-controlled study in another independent Chinese Han population to analyze the correlation between 4 SNPs (rs873549, rs2118610, rs1511412, rs2271289) and keloids phenotypes. 309 keloids patients and 1080 control subjects were included. The results showed that, in the dominant mode of inheritance, the minor allele T of SNP rs2271289 had significantly higher odd ratios (ORs) in the severe keloid group compared with both the controls and the mild keloid group. The ORs were maintained after Bonferroni’s correction (OR: 4.09, 95% CI: 1.78-9.37, P-value 3.25E-04). The ratio of the severe: mild OR for rs2271289 (dominant model) is (4.73/1.84=2.57). Similar associations in SNP rs2271289 were seen for groups with no family history and multiplesite compared with the control groups. No associations between keloid number, family history or severity relative to the controls were observed for the other three SNPs. Our data support that rs2271289 is strongly associated with severe keloids and might contribute to the complexity of clinical features of keloids. PMID:27158346

  19. Spatially extended emission around the Cepheid RS Puppis in near-infrared hydrogen lines. Adaptive optics imaging with VLT/NACO

    NASA Astrophysics Data System (ADS)

    Gallenne, A.; Mérand, A.; Kervella, P.; Girard, J. H. V.

    2011-03-01

    Context. It has been recently discovered that Cepheids harbor circumstellar envelopes (CSEs). RS Pup is the Cepheid that presents the most prominent circumstellar envelope known, the origin of which is not yet understood. Aims: Our purpose is to estimate the flux contribution of the CSE around RS Pup at the one arcsecond scale (~2000 AU) and to investigate its geometry, especially regarding asymmetries, to constrain its physical properties. Methods: We obtained near-infrared images in two narrow band filters centered on λ = 1.644 and 2.180 μm (NB_1.64 and IB_2.18, respectively) that comprise two recombination lines of hydrogen: the 12-4 and 7-4 (Brackett γ) transitions, respectively. We used NACO's cube mode observations in order to improve the angular resolution with the shift-and-add technique, and to qualitatively study the symmetry of the spatially extended emission from the CSE with a statistical study of the speckle noise. Results: We probably detect at a 2σ level an extended emission with a relative flux (compared with the star in the same filter) of 38 ± 17% in the NB_1.64 filter and 24 ± 11% in the IB_2.18 filter. This emission is centered on RS Pup and does not present any detectable asymmetry. We attribute the detected emission to the likely presence of an hydrogen envelope surrounding the star. Based on observations made with ESO telescopes at Paranal observatory under program ID 382.D-0065(A).

  20. A Star's Close Encounter

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Annotated Version

    The potential planet-forming disk (or 'protoplanetary disk') of a sun-like star is being violently ripped away by the powerful winds of a nearby hot O-type star in this image from NASA's Spitzer Space Telescope. At up to 100 times the mass of sun-like stars, O stars are the most massive and energetic stars in the universe.

    The O star can be seen to the right of the image, as the large orange spot with the white center. To the left, the comet-like structure is actually a neighboring solar system that is being destroyed by the O star's powerful winds and intense ultraviolet light.

    In a process called 'photoevaporation,' immense output from the O star heats up the nearby protoplanetary disk so much that gas and dust boil off, and the disk can no longer hold together. Photon (or light) blasts from the O star then strip the potential planet-forming disk off its neighbor star by blowing away evaporated material. This effect is illustrated in the smaller system's comet-like structure.

    The system is located about 2,450 light-years away in the star-forming cloud IC 1396. The image was taken with Spitzer's multiband imaging photometer instrument at 24 microns. The picture is a pseudo-color stretch representing intensity. Yellow and white represent hot areas, whereas purple and blue represent relatively cooler, fainter regions.

  1. Ponderable soliton stars

    NASA Technical Reports Server (NTRS)

    Chiu, Hong-Yee

    1990-01-01

    The theory of Lee and Pang (1987), who obtained solutions for soliton stars composed of zero-temperature fermions and bosons, is applied here to quark soliton stars. Model soliton stars based on a simple physical model of the proton are computed, and the properties of the solitons are discussed, including the important problem of the existence of a limiting mass and thus the possible formation of black holes of primordial origin. It is shown that there is a definite mass limit for ponderable soliton stars, so that during cooling a soliton star might reach a stage beyond which no equilibrium configuration exists and the soliton star probably will collapse to become a black hole. The radiation of ponderable soliton stars may alter the short-wavelength character of the cosmic background radiation, and may be observed as highly redshifted objects at z of about 100,000.

  2. Stars and their Spectra

    NASA Astrophysics Data System (ADS)

    Kaler, James B.

    1997-03-01

    This unique and informative text describes how stars are classified according to their spectral qualities and temperature. James Kaler explains the alphabet of stellar astronomy, running from cool M stars to hot O stars, and tells the story of their evolution. Before embarking on a voyage of cosmic discovery, the author discusses the fundamental properties of stars, their atomic structure and the formation of spectra. Then, Kaler considers each star type individually and explores its spectra in detail. A review of unusual, hard-to-classify stars, and a discussion of data related to the birth, life and death of stars round out the text. This book is an important resource for all amateur astronomers and students of astronomy. Professionals will find it a refreshing read as well.

  3. Binarity and multiperiodicity in high-amplitude δ Scuti stars

    NASA Astrophysics Data System (ADS)

    Derekas, A.; Kiss, L. L.; Bedding, T. R.; Ashley, M. C. B.; Csák, B.; Danos, A.; Fernandez, J. M.; Fűrész, G.; Mészáros, Sz.; Szabó, Gy. M.; Szakáts, R.; Székely, P.; Szatmáry, K.

    2009-04-01

    We have carried out a photometric and spectroscopic survey of bright high-amplitude δ Scuti (HADS) stars. The aim was to detect binarity and multiperiodicity (or both) in order to explore the possibility of combining binary star astrophysics with stellar oscillations. Here, we present the first results for 10, predominantly southern, HADS variables. We detected the orbital motion of RS Gru with a semi-amplitude of ~6.5 kms-1 and 11.5 d period. The companion is inferred to be a low-mass dwarf star in a close orbit around RS Gru. We found multiperiodicity in RY Lep from both photometric and radial velocity data and detected orbital motion in the radial velocities with hints of a possible period of 500-700 d. The data also revealed that the amplitude of the secondary frequency is variable on the time-scale of a few years, whereas the dominant mode is stable. Radial velocities of AD CMi revealed cycle-to-cycle variations, which might be due to non-radial pulsations. We confirmed the multiperiodic nature of BQ Ind, while we obtained the first radial velocity curves of ZZ Mic and BE Lyn. The radial velocity curve and the O-C diagram of CY Aqr are consistent with the long-period binary hypothesis. We took new time series photometry on XX Cyg, DY Her and DY Peg, with which we updated their O-C diagrams.

  4. First Science with the Keck Interferometer Nuller High Spatial Resolution N-Band Observations of the Recurrent Nova RS Ophiuchi

    NASA Technical Reports Server (NTRS)

    Barry, Richard K.; Danchi, W. C.; Traub, W.; Kuchner, M.; Wisniewski, J. P.; Akeson, R.; Colavita, M.; Greenhouse, M, A.; Koresko, C.; Serabyn, E.; Sokoloski, J. L.

    2008-01-01

    We report observations of the nova RS 0phiuchi using the Keck Interferometer Nuller (KIN) taken approximately 3.8 days following the most recent outburst that occurred on 2006 February 12. The KIN operates in N-band from approx. 8 to 12.5 microns in a nulling mode - the sparse aperture equivalent of the conventional coronagraphic technique used in filled aperture te1escopes. In this mode the stellar light is suppressed by a destructive fringe, effectively enhancing the contrast of the circumstellar material located near the star. In a second, constructive-fringe mode, the instrument detects primarily the light from the central, bright source. These are the outer and inner spatial regimes, resprectively. We will describe the capabilities of the KIN, including these unique modes, and outline how they were key in our discovery that dust does not appear to be created in the outburst as in previous models, but instead was created between nova events. We also show how these first results from the KIN are consistent with Spitzer data. The KIN data show evidence of enhanced neutral atomic hydrogen emission and atomic metals including silicon located in the inner spatial regime near the white dwarf (WD) relative to the outer regime. There are also nebular emission lines and evidence of hot silicate dust in the outer spatial region, centered at approximately 17 AU from the WD, that are not found in the inner regime. The KIN and Spitzer data suggest that these emissions were excited by the nova flash in the outer spatial regime before the blast wave reached these regions. We describe the present results in terms of a new model for dust creation in recurrent novae that includes an increase in density in the plane of the orbit of the two stars created by a spiral shock wave caused by the motion of the stars through the cool wind of the red giant star. These data show the power and potential of the nulling technique which has been developed for the detection of Earth-like planets around nearby stars for the Terrestrial Planet Finder and Darwin missions.

  5. Association between BDNF-rs6265 and obesity in the Boston Puerto Rican Health Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study is to examine a functional variant (rs6265) in the BDNF gene interacting with dietary intake modulate obesity traits in the Boston Puerto Rican Health Study population. BDNF rs6265 was genotyped in 1147 Puerto Ricans (aged 45-75 years), and examined for association with o...

  6. CLU rs9331888 Polymorphism Contributes to Alzheimer's Disease Susceptibility in Caucasian But Not East Asian Populations.

    PubMed

    Zhang, Shuyan; Li, Xuling; Ma, Guoda; Jiang, Yongshuai; Liao, Mingzhi; Feng, Rennan; Zhang, Liangcai; Liu, Jiafeng; Wang, Guangyu; Zhao, Bin; Jiang, Qinghua; Li, Keshen; Liu, Guiyou

    2016-04-01

    Large-scale genome-wide association studies (GWAS) identified three single nucleotide polymorphisms rs11136000, rs2279590, and rs9331888 in CLU gene to be significantly associated with Alzheimer's disease (AD) in Caucasian ancestry. Both rs11136000 and rs2279590 variants were successfully replicated in Asian population. However, previous studies reported either a weak association or no association between rs9331888 polymorphism and AD in Asian population. Here, we searched the PubMed, AlzGene, and Google Scholar databases. We selected 12 independent studies that evaluated the association between the rs9331888 polymorphism and AD using a case-control design. Using an additive model, we did not identify significant heterogeneity among these 12 studies. We observed significant association between rs9331888 polymorphism and AD in pooled populations (P = 2.26E - 07, odds ratio (OR) = 1.10, 95 % confidence interval (CI) 1.06-1.14). In subgroup analysis, we did not identify significant heterogeneity in both Asian and Caucasian populations. We identified significant association in Caucasian population (P = 1.67E - 08, OR = 1.13, 95 % CI 1.08-1.18) but not in East Asian population (P = 0.49, OR = 1.02, 95 % CI 0.96-1.10). PMID:25633098

  7. Identification of rs671, a common variant of ALDH2, as a gout susceptibility locus.

    PubMed

    Sakiyama, Masayuki; Matsuo, Hirotaka; Nakaoka, Hirofumi; Yamamoto, Ken; Nakayama, Akiyoshi; Nakamura, Takahiro; Kawai, Sayo; Okada, Rieko; Ooyama, Hiroshi; Shimizu, Toru; Shinomiya, Nariyoshi

    2016-01-01

    Gout is a common disease resulting from hyperuricemia. Recently, a genome-wide association study identified an association between gout and a single nucleotide polymorphism (SNP) rs2188380, located on an intergenic region between MYL2 and CUX2 on chromosome 12. However, other genes around rs2188380 could possibly be gout susceptibility genes. Therefore, we performed a fine-mapping study of the MYL2-CUX2 region. From 8,595 SNPs in the MYL2-CUX2 region, 9 tag SNPs were selected, and genotyping of 1,048 male gout patients and 1,334 male controls was performed by TaqMan method. Eight SNPs showed significant associations with gout after Bonferroni correction. rs671 (Glu504Lys) of ALDH2 had the most significant association with gout (P = 1.7 × 10(-18), odds ratio = 0.53). After adjustment for rs671, the other 8 SNPs no longer showed a significant association with gout, while the significant association of rs671 remained. rs671 has been reportedly associated with alcohol drinking behavior, and it is well-known that alcohol drinking elevates serum uric acid levels. These data suggest that rs671, a common functional SNP of ALDH2, is a genuine gout-associated SNP in the MYL2-CUX2 locus and that "A" allele (Lys) of rs671 plays a protective role in the development of gout. PMID:27181629

  8. Nanostructured lipid carrier surface modified with Eudragit RS 100 and its potential ophthalmic functions

    PubMed Central

    Zhang, Wenji; Li, Xuedong; Ye, Tiantian; Chen, Fen; Yu, Shihui; Chen, Jianting; Yang, Xinggang; Yang, Na; Zhang, Jinsong; Liu, Jinlu; Pan, Weisan; Kong, Jun

    2014-01-01

    This study was carried out to evaluate the ocular performance of a cationic Eudragit (EDU) RS 100-coated nanostructured lipid carrier (NLC). The genistein encapsulated NLC (GEN-NLC) was produced using the melt-emulsification technique followed by surface absorption of EDU RS 100. The EDU RS 100 increased the surface zeta potential from −7.46 mV to +13.60 mV, by uniformly forming a spherical coating outside the NLC surface, as shown by transmission electron microscopy images. The EDU RS 100 on the NLC surface effectively improved the NLC stability by inhibiting particle size growth. The obtained EDU RS 100-GEN-NLC showed extended precorneal clearance and a 1.22-fold increase in AUC (area under the curve) compared with the bare NLC in a Gamma scintigraphic evaluation. The EDU RS 100 modification also significantly increased corneal penetration producing a 3.3-fold increase in apparent permeability coefficients (Papp) compared with references. Draize and cytotoxicity testing confirmed that the developed EDU RS 100-GEN-NLC was nonirritant to ocular tissues and nontoxic to corneal cells. These results indicate that the NLC surface modified by EDU RS 100 significantly improves the NLC properties and exhibits many advantages for ocular use. PMID:25246787

  9. Identification of rs671, a common variant of ALDH2, as a gout susceptibility locus

    PubMed Central

    Sakiyama, Masayuki; Matsuo, Hirotaka; Nakaoka, Hirofumi; Yamamoto, Ken; Nakayama, Akiyoshi; Nakamura, Takahiro; Kawai, Sayo; Okada, Rieko; Ooyama, Hiroshi; Shimizu, Toru; Shinomiya, Nariyoshi

    2016-01-01

    Gout is a common disease resulting from hyperuricemia. Recently, a genome-wide association study identified an association between gout and a single nucleotide polymorphism (SNP) rs2188380, located on an intergenic region between MYL2 and CUX2 on chromosome 12. However, other genes around rs2188380 could possibly be gout susceptibility genes. Therefore, we performed a fine-mapping study of the MYL2-CUX2 region. From 8,595 SNPs in the MYL2-CUX2 region, 9 tag SNPs were selected, and genotyping of 1,048 male gout patients and 1,334 male controls was performed by TaqMan method. Eight SNPs showed significant associations with gout after Bonferroni correction. rs671 (Glu504Lys) of ALDH2 had the most significant association with gout (P = 1.7 × 10−18, odds ratio = 0.53). After adjustment for rs671, the other 8 SNPs no longer showed a significant association with gout, while the significant association of rs671 remained. rs671 has been reportedly associated with alcohol drinking behavior, and it is well-known that alcohol drinking elevates serum uric acid levels. These data suggest that rs671, a common functional SNP of ALDH2, is a genuine gout-associated SNP in the MYL2-CUX2 locus and that “A” allele (Lys) of rs671 plays a protective role in the development of gout. PMID:27181629

  10. Association of IL-1α rs17561 and IL-1 RN rs315952 polymorphisms with Tourette syndrome: a family-based study

    PubMed Central

    He, Fan; Shao, Xiaohui; Yi, Mingji; Wang, Yu; Wang, Chuan-Yue; Liu, Shiguo

    2015-01-01

    Aim: Immune system dysregulation has been implicated to play a key role in pathogenesis of Tourette syndrome (TS). IL-1α and IL-1RN are important inflammatory cytokines that mediate the inflammation. In this study, we investigated the relationship between single-nucleotide polymorphisms (SNPs) of IL-1α and IL-1RN and the susceptibility to TS in Chinese Han population. Methods: A total of 276 children with TS and their parents were recruited in the study. All DNA from our subjects were genotyped for SNPs of IL-1α rs17561 and IL-1RN rs315952 using predesigned TaqMan SNP genotyping assay. The genetic contributions of two polymorphisms were evaluated using transmission disequilibrium test (TDT) and haplotype relative risk (HRR) design. In addition, to increase the efficiency of the test, the haplotype-based HRR (HHRR) was performed. Results: No significant differences were observed in allelic and genotypic frequency of rs17561 in IL-1α and rs315952 in IL-1RN between the transmitted group and non-transmitted group (for IL-1α rs17561: TDT=0.890, df=1, P=0.402; HRR=1.011, X2=3.016, P=0.082, 95% CI=0.999-1.024; for IL-1RN rs315952: TDT=0.095, df=1, P=0.805; HRR=0.984, X2=0.008, P=0.929, 95% CI=0.695-1.394). Similarly, the analysis of HHRR also did not support a significant association (for IL-1α rs17561: HHRR=1.226, X2=0.915, P=0.339, 95% CI=0.807-1.863; for IL-1RN rs315952: HHRR=0.963, X2=0.094, P=0.759, 95% CI=0.758-1.225). Conclusion: Our results suggest that IL-1α rs17561 and IL-1RN rs315952 polymorphisms may not be associated with susceptibility to TS in Chinese Han population. However, the results still need to be replicated in a larger sample size and different populations. PMID:26097611

  11. Impact of Host IL28B rs12979860, rs8099917 in Interferon Responsiveness and Advanced Liver Disease in Chronic Genotype 3 Hepatitis C Patients

    PubMed Central

    Mukherjee, Anirban; Chaudhuri, Sujit; Chandra, Alok; Konar, Asokananda; Sadhukhan, Provash Chandra

    2014-01-01

    Background and Aims Genetic polymorphisms near interleukin 28B gene are associated with spontaneous and treatment induced clearance of hepatitis C virus (HCV). Our objective was to evaluate the impact of interleukin 28B single nucleotide polymorphism (rs12979860, rs8099917) variability in HCV genotype 3 infected populations. Methods 400 hepatitis C seroreactive patients from different population groups in Eastern and North Eastern part of India were assessed for host and viral genotypic analysis. 83 HCV genotype 3 infected patients were administered pegylated interferon- ribavirin therapy. Viral genotyping was performed using nested reverse transcriptase-PCR followed by direct sequencing methods. Host interleukin 28B genotyping was performed using real-time PCR based single nucleotide polymorphism analysis. Results Out of 400 hepatitis C seroreactive individuals, 73.25% were found to be RNA positive. HCV genotype 3 (65.87%) was found to be the major circulating strain in this region followed by genotype 1 (32.08%). rs12979860 CC genotype was significantly associated with sustained virological response in HCV genotype 3 infected population. In patients achieving rapid virological response, favourable CC/TT allele at rs12979860, rs8099917 was found to be predominant at both the alleles at 77%, 73.2% respectively; whereas in case of patients with relapsed HCV infection CT, TG alleles were found to be predominant. Additionally, CC genotypes at rs12979860 were found to be associated with sustained virological response in patients with high viral load (OR = 6.75, 0.05rs12979860 TT, rs8099917 GG alleles were present in 34%, 27.6% patients with relapsed HCV infection respectively. Also unfavourable CT, TG genotypes were found to be predominant in patients with advanced stages of liver disease. Conclusion CC, TT the two favourable markers at SNPs rs12979860 and rs8099917 are strongly associated with sustained virological response in genotype 3 infected populations. This information will aid clinicians to effectively design response based treatment regimen. PMID:24914551

  12. Water quality assessment of the Sinos River - RS, Brazil.

    PubMed

    Steffens, C; Klauck, C R; Benvenuti, T; Silva, L B; Rodrigues, M A S

    2015-12-01

    Worldwide environmental pollution is increasing at the same rate as social and economic development. This growth, however, is disorganized and leads to increased degradation of water resources. Water, which was once considered inexhaustible, has become the focus of environmental concerns because it is essential for life and for many production processes. This article describes monitoring of the water quality at three points along the Sinos River (RS, Brazil), one in each of the upper, middle and lower stretches. The points were sampled in 2013 and again in 2014. The water samples were analyzed to determine the following physical and chemical parameters plus genotoxicity to fish: metals (Cr, Fe, Al), chemical oxygen demand, biochemical oxygen demand, chlorides, conductivity, total suspended solids, total phosphorous, total and fecal coliforms, pH, dissolved oxygen, turbidity, total Kjeldahl nitrogen nitrate and ammoniacal nitrogen. Genotoxicity was tested by exposing individuals of the species Astyanax jacuhiensis to water samples and then comparing them with a control group exposed to water from the public water supply. The results confirmed the presence of substances with genotoxic potential at the sample points located in the middle and lower stretches of the river. The results for samples from the upper stretch, at P1, did not exhibit differences in relation to the control group. The physical and chemical analyses did not detect reductions in water quality in the lower stretch, as had been expected in view of the large volumes of domestic and industrial effluents discharged into this part of the river. PMID:26628228

  13. Preparative enantioseparation of (RS)-baclofen: determination of molecular dissymmetry.

    PubMed

    Vashistha, Vinod Kumar; Bhushan, Ravi

    2015-04-01

    The present work reports preparative enantioseparation of (RS)-baclofen using thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Diastereomers were synthesized using a new monochloro-s-triazine-based chiral derivatizing reagent (CDR), namely, N-(4-chloro-6-piperidinyl-[1,3,5]-triazine-2-yl)-L-phenylalanine, under microwave irradiation. Acetonitrile-0.1% aq. triflouroacetic acid in gradient elution mode and CH3 OH-CH2 Cl2 (4:5; v/v) were successful as mobile phase in HPLC and TLC, respectively. The two diastereomers were isolated by preparative TLC. Molecular dissymmetry was established by developing the lowest energy optimized structures of the diastereomers based on Density Functional Theory and with the help of (1) H NMR showing anisotropic effect associated with aromatic ring of s-triazine (in the CDR). The configuration of diastereomers was established as [L-Phe-(R)-Bac] and [L-Phe-(S)-Bac], where the first notation refers to the configuration of chiral auxiliary (of the CDR) and the second to that of the analyte Bac. Limits of detection were found to be 0.056 and 0.061?ng?mL(-1), respectively, for the two diastereomers. Determination of absolute configuration of the two diastereomers lent support to the elution order and separation mechanism. PMID:25683386

  14. Performance Characterization of RaPToRS Systems

    NASA Astrophysics Data System (ADS)

    Shibata, K.; Krieger, M.; Fallica, J.; Henchen, R.; Pogozelski, E.; Padalino, S.; SUNY Geneseo Collaboration; LaboratoryLaser Energetics at University of Rochester Collaboration

    2011-10-01

    The Rapid Pneumatic Transport of Radioactive Samples (RaPToRS) system can quickly and efficiently move radioactive materials from their activation site to a counting station. Facilities such as the NIF and LLE are considering these systems while NRL is currently using one. The system is essentially a 10 cm diameter pneumatic tube with a cylindrical sample carrier. The performance of the system depends on many factors, including the mass of the carrier, length of the tube, angle and difference in height of the tube's endpoints, the carrier's physical design, and the number, type, and distribution of blowers attached to the tube. These factors have been systematically examined to develop the fastest and most reliable system. The most significant factors are the mass and the vertical travel of the carrier. When the carrier mass is low, moving air supports the carrier in the tube, resulting in low friction. The terminal velocity ranges from 13.5 to 2.5 m/s for masses varying from 1 kg to 3 kg. Using a single 1100 W blower, the initial force exerted on the carrier was 11.3 N. This work was supported in part by the US Department of Energy through the LLE.

  15. Rapid Pneumatic Transport of Radioactive Samples - RaPToRS

    NASA Astrophysics Data System (ADS)

    Padalino, S.; Barrios, M.; Sangster, C.

    2005-10-01

    Some ICF neutron activation diagnostics require quick retrieval of the activated sample. Minimizing retrieval times is particularly important when the half-life of the activated material is on the order of the transport time or the degree of radioactivity is close to the background counting level. These restrictions exist in current experiments performed at the Laboratory for Laser Energetics, thus motivating the development of the RaPToRS system. The system has been designed to minimize transportation time while requiring no human intervention during transport or counting. These factors will be important if the system is to be used at the NIF where radiological hazards will be present during post activation. The sample carrier is pneumatically transported via a 4 inch ID PVC pipe to a remote location in excess of 100 meters from the activation site at a speed of approximately 7 m/s. It arrives at an end station where it is dismounted robotically from the carrier and removed from its hermetic package. The sample is then placed by the robot in a counting station. This system is currently being developed to measure back-to-back gamma rays produced by positron annihilation which were emitted by activated graphite. Funded in part by the U.S. DOE under sub contract with LLE at the University of Rochester.

  16. An investment in the Three Rs can be very profitable.

    PubMed

    Curren, Rodger

    2009-12-01

    The Principles of Humane Experimental Technique by William Russell and Rex Burch provides exceptional value, both to practitioners of alternative methodologies and to bibliophiles who enjoy the pursuit of an out-of-print book. I was stimulated to find an original edition by my first visits to FRAME and its Chairman, Michael Balls. The search continued for several years, until I was able to find an edition suitable for presentation to him. During this hunt, I was able to learn a great deal about the Three Rs of Replacement, Reduction and Refinement, and the programmes that FRAME initiated to educate scientists and the general public about alternative approaches. Very importantly, I was able to use many of FRAME's successful strategies to build up a similar organisation in the United States, the Institute for In Vitro Sciences. The double value of this book is now revealed - not only are its concepts scientifically and ethically valuable, but the price now being charged by secondhand booksellers means a more than ten-fold increase in the value of my investment! PMID:20105009

  17. Two-component signal transduction system SaeRS positively regulates Staphylococcus epidermidis glucose metabolism.

    PubMed

    Lou, Qiang; Qi, Yijun; Ma, Yuanfang; Qu, Di

    2014-01-01

    Staphylococcus epidermidis, which is a causative pathogen of nosocomial infection, expresses its virulent traits such as biofilm and autolysis regulated by two-component signal transduction system SaeRS. In this study, we performed a proteomic analysis of differences in expression between the S. epidermidis 1457 wild-type and saeRS mutant to identify candidates regulated by saeRS using two-dimensional gel electrophoresis (2-DE) combined with matrix-assisted laser desorption/lonization mass spectrometry (MALDI-TOF-MS). Of 55 identified proteins that significantly differed in expression between the two strains, 15 were upregulated and 40 were downregulated. The downregulated proteins included enzymes related to glycolysis and TCA cycle, suggesting that glucose is not properly utilized in S. epidermidis when saeRS was deleted. The study will be helpful for treatment of S. epidermidis infection from the viewpoint of metabolic modulation dependent on two-component signal transduction system SaeRS. PMID:24592198

  18. Two-Component Signal Transduction System SaeRS Positively Regulates Staphylococcus epidermidis Glucose Metabolism

    PubMed Central

    Qi, Yijun; Ma, Yuanfang; Qu, Di

    2014-01-01

    Staphylococcus epidermidis, which is a causative pathogen of nosocomial infection, expresses its virulent traits such as biofilm and autolysis regulated by two-component signal transduction system SaeRS. In this study, we performed a proteomic analysis of differences in expression between the S. epidermidis 1457 wild-type and saeRS mutant to identify candidates regulated by saeRS using two-dimensional gel electrophoresis (2-DE) combined with matrix-assisted laser desorption/lonization mass spectrometry (MALDI-TOF-MS). Of 55 identified proteins that significantly differed in expression between the two strains, 15 were upregulated and 40 were downregulated. The downregulated proteins included enzymes related to glycolysis and TCA cycle, suggesting that glucose is not properly utilized in S. epidermidis when saeRS was deleted. The study will be helpful for treatment of S. epidermidis infection from the viewpoint of metabolic modulation dependent on two-component signal transduction system SaeRS. PMID:24592198

  19. A lack of association between the CRP rs2794520 polymorphism and coronary artery disease

    PubMed Central

    LIAN, JIANGFANG; LI, JUNXING; DAI, DONGJUN; FANG, PEILIANG; ZHOU, JIANQING; DUAN, SHIWEI

    2015-01-01

    Coronary artery disease (CAD) is mainly caused by atherosclerosis, which is closely associated with the C-reactive protein (CRP), a systemic inflammatory mediator. The aim of the present study was to examine whether the CRP rs2794520 polymorphism played a role in the risk of CAD. A total of 459 CAD patients and 432 non-CAD controls were recruited in the case-control study. Genotyping was performed on the SEQUENOM Mass-ARRAY iPLEX platform according to the manufacturer's instructions. The results showed that CRP rs2794520 was not associated with CAD. A further breakdown analysis by age or gender also indicated a lack of association between rs2794520 and CAD. In addition, the CRP rs2794520 polymorphism was not associated with the severity of CAD, which was represented by the number of coronary arteries with stenosis. In conclusion, there was no contribution of the CRP rs2794520 polymorphism to the risk of CAD. PMID:25469258

  20. Lack of association between SNP rs3914132 of the RELN gene and otosclerosis in India.

    PubMed

    Priyadarshi, S; Panda, K C; Panda, A K; Ramchander, P V

    2010-01-01

    Otosclerosis (MIM 166800) is primarily a metabolic bone disorder of the otic capsule, which leads to bony fixation of the stapedial footplate in the oval window; it is among the most common causes of acquired hearing loss. The etiology of this disease is largely unknown, although epidemiological studies suggest the involvement of both genetic and environmental factors. Recently, a reelin gene, SNP rs3914132, located in intron 2, was shown to be associated with otosclerosis in a European population. When we sequenced blood DNA samples of 85 individuals with otosclerosis and 85 controls, four SNPs of this gene: rs3914131 (P = 0.6463), rs3914132 (P = 0.1822), rs9641319 (P = 0.7371), and rs10227303 (P = 0.5669) were not significantly associated with this disease. In one familial case, a novel variant (C/T) at contig position 2923488 was found to be inherited by the proband and affected family members. PMID:20882487

  1. The ARIES-RS power core -- Recent development in Li/V designs

    SciTech Connect

    Sze, D.K.; Billone, M.C.; Hua, T.Q.

    1997-04-01

    The ARIES-RS fusion power plant design study is based on reversed-shear (RS) physics with a Li/V (lithium breeder and vanadium structure) blanket. The reversed-shear discharge has been documented in many large tokamak experiments. The plasma in the RS mode has a high beta, low current, and low current drive requirements. Therefore, it is an attractive physics regime for a fusion power plant. The blanket system based on a Li/V has high temperature operating capability, good tritium breeding, excellent high heat flux removal capability, long structural life time, low activation, low after heat and good safety characteristics. For these reasons, the ARIES-RS reactor study selected Li/V as the reference blanket. The combination of attractive physics and attractive blanket engineering is expected to result in a superior power plant design. This paper summarizes the power core design of the ARIES-RS power plant study.

  2. Dark stars: a review

    NASA Astrophysics Data System (ADS)

    Freese, Katherine; Rindler-Daller, Tanja; Spolyar, Douglas; Valluri, Monica

    2016-06-01

    Dark stars are stellar objects made (almost entirely) of hydrogen and helium, but powered by the heat from dark matter annihilation, rather than by fusion. They are in hydrostatic and thermal equilibrium, but with an unusual power source. Weakly interacting massive particles (WIMPs), among the best candidates for dark matter, can be their own antimatter and can annihilate inside the star, thereby providing a heat source. Although dark matter constitutes only ≲ 0.1% of the stellar mass, this amount is sufficient to power the star for millions to billions of years. Thus, the first phase of stellar evolution in the history of the Universe may have been dark stars. We review how dark stars come into existence, how they grow as long as dark matter fuel persists, and their stellar structure and evolution. The studies were done in two different ways, first assuming polytropic interiors and more recently using the MESA stellar evolution code; the basic results are the same. Dark stars are giant, puffy (∼10 AU) and cool (surface temperatures  ∼10 000 K) objects. We follow the evolution of dark stars from their inception at  ∼1{{M}ȯ} as they accrete mass from their surroundings to become supermassive stars, some even reaching masses  >{{10}6}{{M}ȯ} and luminosities  >{{10}10}{{L}ȯ} , making them detectable with the upcoming James Webb Space Telescope. Once the dark matter runs out and the dark star dies, it may collapse to a black hole; thus dark stars may provide seeds for the supermassive black holes observed throughout the Universe and at early times. Other sites for dark star formation may exist in the Universe today in regions of high dark matter density such as the centers of galaxies. The current review briefly discusses dark stars existing today, but focuses on the early generation of dark stars.

  3. A radio survey of weak T Tauri stars in Taurus-Auriga

    SciTech Connect

    O'neal, D.; Feigelson, E.D.; Mathieu, R.D.; Myers, P.C. Wisconsin Univ., Madison Harvard-Smithsonian Center for Astrophysics, Cambridge, MA )

    1990-11-01

    A multi-epoch 5 GHz survey of candidate or confirmed weak T Tauri stars in the Taurus-Auriga molecular cloud complex was conducted with the Very Large Array. The stars were chosen from those having detectable X-ray or chromospheric emission, and weak-emission-line pre-main-sequence stars found by other means. Snapshots of 99 VLA fields containing 119 candidate stars were obtained with a sensitivity of 0.7 mJy; most fields were observed on two or three dates. Nine radio sources coincident with cataloged stars were found. One may be an RS CVn binary system; the other eight are pre-main-sequence stars. Three of the detected stars - HD 283447, V410 Tau, and FK X-ray 1 - were previously known radio sources. Five new detections are Herbig's Anon 1, Hubble 4, HDE 283572, Elias 12, and HK Tau/c. At least five of the sources are variable, and no linear or circular polarization was found. Several lines of evidence suggest that the radio-detected weak T Tauri stars are quite young, perhaps younger on average than nondetected stars. 54 refs.

  4. Accuracy Assessment and Correction of Vaisala RS92 Radiosonde Water Vapor Measurements

    NASA Technical Reports Server (NTRS)

    Whiteman, David N.; Miloshevich, Larry M.; Vomel, Holger; Leblanc, Thierry

    2008-01-01

    Relative humidity (RH) measurements from Vaisala RS92 radiosondes are widely used in both research and operational applications, although the measurement accuracy is not well characterized as a function of its known dependences on height, RH, and time of day (or solar altitude angle). This study characterizes RS92 mean bias error as a function of its dependences by comparing simultaneous measurements from RS92 radiosondes and from three reference instruments of known accuracy. The cryogenic frostpoint hygrometer (CFH) gives the RS92 accuracy above the 700 mb level; the ARM microwave radiometer gives the RS92 accuracy in the lower troposphere; and the ARM SurTHref system gives the RS92 accuracy at the surface using 6 RH probes with NIST-traceable calibrations. These RS92 assessments are combined using the principle of Consensus Referencing to yield a detailed estimate of RS92 accuracy from the surface to the lowermost stratosphere. An empirical bias correction is derived to remove the mean bias error, yielding corrected RS92 measurements whose mean accuracy is estimated to be +/-3% of the measured RH value for nighttime soundings and +/-4% for daytime soundings, plus an RH offset uncertainty of +/-0.5%RH that is significant for dry conditions. The accuracy of individual RS92 soundings is further characterized by the 1-sigma "production variability," estimated to be +/-1.5% of the measured RH value. The daytime bias correction should not be applied to cloudy daytime soundings, because clouds affect the solar radiation error in a complicated and uncharacterized way.

  5. Variable stars in the open cluster NGC 2141

    NASA Astrophysics Data System (ADS)

    Luo, Yang-Ping

    2015-05-01

    We report the results of a search for variable stars in the open cluster NGC 2141. Ten variable stars are detected, among which nine are new variable stars and they are classified as three short-period W UMa-type eclipsing binaries, two EA-type eclipsing binaries, one EB-type eclipsing binary, one very short-period RS CVn-type eclipsing binary, one d-type RR Lyrae variable star, and one unknown type of variable star. The membership and physical properties are discussed, based on their light curves, positions in the color magnitude diagrams, spatial locations and periods. A known EB-type eclipsing binary is also identified as a blue straggler candidate in the cluster. Furthermore, we find that all eclipsing contact binaries have prominent asymmetric eclipses and display the O'Connell effect, which increases with a decrease in orbital periods. This suggests that the O'Connell effect is probably related to the evolution of the orbital period in short period eclipsing binary systems. Supported by the National Natural Science Foundation of China.

  6. Phemenological Modelling of a Group of Eclipsing Binary Stars

    NASA Astrophysics Data System (ADS)

    Andronov, Ivan L.; Tkachenko, Mariia G.; Chinarova, Lidia L.

    2016-03-01

    Phenomenological modeling of variable stars allows determination of a set of the parameters, which are needed for classification in the "General Catalogue of Variable Stars" and similar catalogs. We apply a recent method NAV ("New Algol Variable") to eclipsing binary stars of different types. Although all periodic functions may be represented as Fourier series with an infinite number of coefficients, this is impossible for a finite number of the observations. Thus one may use a restricted Fourier series, i.e. a trigonometric polynomial (TP) of order s either for fitting the light curve, or to make a periodogram analysis. However, the number of parameters needed drastically increases with decreasing width of minimum. In the NAV algorithm, the special shape of minimum is used, so the number of parameters is limited to 10 (if the period and initial epoch are fixed) or 12 (not fixed). We illustrate the NAV method by application to a recently discovered Algol-type eclipsing variable 2MASS J11080308-6145589 (in the field of previously known variable star RS Car) and compare results to that obtained using the TP fits. For this system, the statistically optimal number of parameters is 44, but the fit is still worse than that of the NAV fit. Application to the system GSC 3692-00624 argues that the NAV fit is better than the TP one even for the case of EW-type stars with much wider eclipses. Model parameters are listed.

  7. Intelligent star tracker

    NASA Astrophysics Data System (ADS)

    Clark, Natalie

    2001-11-01

    Current state-of-the-art commercial star sensors typically weigh 15 pounds, attain 5 to 10 arc-second accuracy, and use roughly 10 watts of power. Unfortunately, the current state-of-the-art commercial star sensors do not meet many of NASA's next-generation spacecraft and instrument needs. Nor do they satisfy Air Force's needs for micro/nano-satellite systems. In an effort to satisfy micro/nano satellite mission needs the Air Force Research Laboratory is developing an intelligent star Tracker, called IntelliStar, which incorporates several novel technologies including Silicon carbide optical housing, MEMs based adaptive optic technologies, smart active pixels, and algebraic coding theory. The design considerations associated with the development of the IntelliStar system are presented along with experimental results which characterize each technologies contribution to overall system performance. In addition to being light weight, the IntelliStar System offers advantages in speed, size, power consumption, and radiation tolerance.

  8. Cooling of dense stars

    NASA Technical Reports Server (NTRS)

    Tsuruta, S.

    1972-01-01

    Cooling rates were calculated for neutron stars of about one solar mass and 10 km radius, with magnetic fields from zero to about 10 to the 14th power gauss, for extreme cases of maximum and zero superfluidity. The results show that most pulsars are so cold that thermal ionization of surface atoms would be negligible. Nucleon superfluidity and crystallization of heavy nuclei were treated quantitatively, and more realistic hadron star models were chosen. Cooling rates were calculated for a stable hyperon star near the maximum mass limit, a medium weight neutron star, and a light neutron star with neutron-rich heavy nuclei near the minimum mass limit. Results show that cooling rates are a sensitive function of density. The Crab and Vela pulsars are considered, as well as cooling of a massive white dwarf star.

  9. The Two-Component System GrvRS (EtaRS) Regulates ace Expression in Enterococcus faecalis OG1RF

    PubMed Central

    Singh, Kavindra V.; La Rosa, Sabina Leanti; Cohen, Ana Luisa V.; Murray, Barbara E.

    2014-01-01

    Expression of ace (adhesin to collagen of Enterococcus faecalis), encoding a virulence factor in endocarditis and urinary tract infection models, has been shown to increase under certain conditions, such as in the presence of serum, bile salts, urine, and collagen and at 46°C. However, the mechanism of ace/Ace regulation under different conditions is still unknown. In this study, we identified a two-component regulatory system GrvRS as the main regulator of ace expression under these stress conditions. Using Northern hybridization and β-galactosidase assays of an ace promoter-lacZ fusion, we found transcription of ace to be virtually absent in a grvR deletion mutant under the conditions that increase ace expression in wild-type OG1RF and in the complemented strain. Moreover, a grvR mutant revealed decreased collagen binding and biofilm formation as well as attenuation in a murine urinary tract infection model. Here we show that GrvR plays a major role in control of ace expression and E. faecalis virulence. PMID:25385790

  10. U Gem Stars

    NASA Astrophysics Data System (ADS)

    Kaitchuck, R.; Murdin, P.

    2000-11-01

    U Geminorum (U Gem) is the prototype for one subclass of dwarf nova (DN) systems. U Gem stars, like other DNs, brighten by factors of hundreds to thousands, sometimes in just a few hours. The eruptions recur quasi-periodically on intervals of weeks to years, with durations from a few days to a few weeks. U Gem stars, like all cataclysmic variables, are BINARY STAR systems consisting of a low-ma...

  11. The Theatre of stars

    NASA Astrophysics Data System (ADS)

    Cavedon, M.; Peri, F.

    Planetariums are special instruments in education and didactics of Astronomy and Astrophysics. Since 1930 the Planetarium of Milan, the most important planetarium in Italy, has played a fundamental role in outreach to the public. Italian tradition always preferred didactics in ``live'' lessons. Now technology expands the potential of the star projector and the theatre of stars is a real window on the universe, where you can travel among the stars and galaxies, to reach the boundaries of space and time.

  12. Association of ADORA1 rs2228079 and ADORA2A rs5751876 Polymorphisms with Gilles de la Tourette Syndrome in the Polish Population

    PubMed Central

    Safranow, Krzysztof; Żekanowski, Cezary

    2015-01-01

    Background Gilles de la Tourette syndrome (GTS) is a neurodevelopmental disorder characterized by motor and vocal tics. Hyperactivity of dopaminergic transmission is considered a prime abnormality in the pathophysiology of tics. There are reciprocal antagonistic interactions between adenosine and dopamine transmission. The aim of the study was to analyze the association of two polymorphisms, rs2228079 in ADORA1 and rs5751876 in ADORA2A, with the risk of GTS and co-morbid disorders. Material and Methods A total of 162 Polish GTS patients and 270 healthy persons were enrolled in the study. Two polymorphisms were selected on the basis of knowledge of SNPs frequencies in ADORA1 and ADORA2A. Chi-square test was used for allelic and genotypic association studies. Association of genotypes with age of tic onset was analyzed with Mann-Whitney test. Multivariate logistic regression was used to find independent predictors of GTS risk. Results We found that the risk of GTS was associated with rs2228079 and rs5751876 polymorphisms. The GG+GT genotypes of rs2228079 in ADORA1 were underrepresented in GTS patients (p = 0.011), whereas T allele of rs5751876 in ADORA2A was overrepresented (p = 0.017). The GG genotype of rs2228079 was associated with earlier age of tic onset (p = 0.046). We found also that the minor allele G of rs2228079 was more frequent in GTS patients with depression as compared to the patients without depression (p = 0.015). Also the genotype GG was significantly more frequent in patients with obsessive compulsive disorder/behavior (OCD/OCB, p = 0.021) and depression (p = 0.032), as compared to the patients without these co-morbidities. The minor allele T frequency of rs5751876 was lower in GTS patients with co-morbid attention deficit hyperactivity disorder (p = 0.022), and TT+TC genotypes were less frequent in the non-OCD anxiety disorder group (p = 0.045). Conclusion ADORA1 and ADORA2A variants are associated with the risk of GTS, co-morbid disorders, and may affect the age of tic onset. PMID:26317759

  13. Delta Scuti stars: Theory

    SciTech Connect

    Guzik, J.A.

    1998-03-01

    The purpose of asteroseismology is not only to derive the internal structure of individual stars from their observed oscillation frequencies, but also to test and extend one`s understanding of the physics of matter under the extremes of temperature, density, and pressure found in stellar interiors. In this review, the author hopes to point out what one can learn about the Sun by studying {delta} Scuti stars, as well as what one can learn about stars more massive or evolved than the Sun. He discusses some of the difficulties in theoretical approaches to asteroseismology for {delta} Scuti stars, using FG Vir, {delta} Scuti, and CD-24{degree} 7599 as examples.

  14. Introduction to neutron stars

    NASA Astrophysics Data System (ADS)

    Lattimer, James M.

    2015-02-01

    Neutron stars contain the densest form of matter in the present universe. General relativity and causality set important constraints to their compactness. In addition, analytic GR solutions are useful in understanding the relationships that exist among the maximum mass, radii, moments of inertia, and tidal Love numbers of neutron stars, all of which are accessible to observation. Some of these relations are independent of the underlying dense matter equation of state, while others are very sensitive to the equation of state. Recent observations of neutron stars from pulsar timing, quiescent X-ray emission from binaries, and Type I X-ray bursts can set important constraints on the structure of neutron stars and the underlying equation of state. In addition, measurements of thermal radiation from neutron stars has uncovered the possible existence of neutron and proton superfluidity/superconductivity in the core of a neutron star, as well as offering powerful evidence that typical neutron stars have significant crusts. These observations impose constraints on the existence of strange quark matter stars, and limit the possibility that abundant deconfined quark matter or hyperons exist in the cores of neutron stars.

  15. Delta Scuti stars: Theory

    NASA Technical Reports Server (NTRS)

    Guzik, J. A.

    1998-01-01

    The purpose of asteroseismology is not only to derive the internal structure of individual stars from their observed oscillation frequencies, but also to test and extend one's understanding of the physics of matter under the extremes of temperature, density, and pressure found in stellar interiors. In this review, the author hopes to point out what one can learn about the Sun by studying (delta) Scuti stars, as well as what one can learn about stars more massive or evolved than the Sun. He discusses some of the difficulties in theoretical approaches to asteroseismology for (delta) Scuti stars, using FG Vir, (delta) Scuti, and CD-24(degree) 7599 as examples.

  16. Introduction to neutron stars

    SciTech Connect

    Lattimer, James M.

    2015-02-24

    Neutron stars contain the densest form of matter in the present universe. General relativity and causality set important constraints to their compactness. In addition, analytic GR solutions are useful in understanding the relationships that exist among the maximum mass, radii, moments of inertia, and tidal Love numbers of neutron stars, all of which are accessible to observation. Some of these relations are independent of the underlying dense matter equation of state, while others are very sensitive to the equation of state. Recent observations of neutron stars from pulsar timing, quiescent X-ray emission from binaries, and Type I X-ray bursts can set important constraints on the structure of neutron stars and the underlying equation of state. In addition, measurements of thermal radiation from neutron stars has uncovered the possible existence of neutron and proton superfluidity/superconductivity in the core of a neutron star, as well as offering powerful evidence that typical neutron stars have significant crusts. These observations impose constraints on the existence of strange quark matter stars, and limit the possibility that abundant deconfined quark matter or hyperons exist in the cores of neutron stars.

  17. CSTAR star catalogue development

    NASA Technical Reports Server (NTRS)

    Uhde-Lacovara, J. A.

    1986-01-01

    The Continuous Stellar Tracking Attitude Reference (CSTAR) system is an in-house project for the Space Station to provide high accuracy, drift free attitude and angular rate information for the GN&C system. Constraints exist on the star catalogue incorporated in the system. These constraints include the following: mass memory allocated for catalogue storage, star tracker imaging sensitivity, the minimum resolvable separation angle between stars, the width of the field of view of the star tracker, and the desired number of stars to be tracked in a field of view. The Smithsonian Astrophysical Observatory (SAO) catalogue is the basis reference for this study. As it stands, the SAO does not meet the requirements of any of the above constraints. Star selection algorithms have been devised for catalogue optimization. Star distribution statistics have been obtained to aid in the development of these rules. VAX based software has been developed to implement the star selection algorithms. The software is modular and provides a design tool to tailor the catalogue to available star tracker technology. The SAO catalogue has been optimized for the requirements of the present CSTAR system.

  18. Strange Nonchaotic Stars

    NASA Astrophysics Data System (ADS)

    Lindner, John F.; Kohar, Vivek; Kia, Behnam; Hippke, Michael; Learned, John G.; Ditto, William L.

    2015-08-01

    Exploiting the unprecedented capabilities of the planet-hunting Kepler space telescope, which stared at 150 000 stars for four years, we discuss recent evidence that certain stars dim and brighten in complex patterns with fractal features. Such stars pulsate at primary and secondary frequencies whose ratios are near the famous golden mean, the most irrational number. A nonlinear system driven by an irrational ratio of frequencies is generically attracted toward a “strange” behavior that is geometrically fractal without displaying the “butterfly effect” of chaos. Strange nonchaotic attractors have been observed in laboratory experiments and have been hypothesized to describe the electrochemical activity of the brain, but a bluish white star 16 000 light years from Earth in the constellation Lyra may manifest, in the scale-free distribution of its minor frequency components, the first strange nonchaotic attractor observed in the wild. The recognition of stellar strange nonchaotic dynamics may improve the classification of these stars and refine the physical modeling of their interiors. We also discuss nonlinear analysis of other RR Lyrae stars in Kepler field of view and discuss some toy models for modeling these stars.References: 1) Hippke, Michael, et al. "Pulsation period variations in the RRc Lyrae star KIC 5520878." The Astrophysical Journal 798.1 (2015): 42.2) Lindner, John F., et al. "Strange nonchaotic stars." Phys. Rev. Lett. 114, 054101 (2015)

  19. Massive soliton stars

    NASA Technical Reports Server (NTRS)

    Chiu, Hong-Yee

    1990-01-01

    The structure of nontopological solutions of Einstein field equations as proposed by Friedberg, Lee, and Pang (1987) is examined. This analysis incorporates finite temperature effects and pair creation. Quarks are assumed to be the only species that exist in interior of soliton stars. The possibility of primordial creation of soliton stars in the incomplete decay of the degenerate vacuum in early universe is explored. Because of dominance of pair creation inside soliton stars, the luminosity of soliton stars is not determined by its radiative transfer characteristics, and the surface temperature of soliton stars can be the same as its interior temperature. It is possible that soliton stars are intense X-ray radiators at large distances. Soliton stars are nearly 100 percent efficient energy converters, converting the rest energy of baryons entering the interior into radiation. It is possible that a sizable number of baryons may also be trapped inside soliton stars during early epochs of the universe. In addition, if soliton stars exist they could assume the role played by massive black holes in galactic centers.

  20. Prediction of acidity in acetonitrile solution with COSMO-RS.

    PubMed

    Eckert, Frank; Leito, Ivo; Kaljurand, Ivari; Kütt, Agnes; Klamt, Andreas; Diedenhofen, Michael

    2009-04-15

    The COSMO-RS method, a combination of the quantum chemical dielectric continuum solvation model COSMO with a statistical thermodynamics treatment for realistic solvation simulations, has been used for the prediction of pK(a) values in acetonitrile. For a variety of 93 organic acids, the directly calculated values of the free energies of dissociation in acetonitrile showed a very good correlation with the pK(a) values (r(2) = 0.97) in acetonitrile, corresponding to a standard deviation of 1.38 pK(a) units. Thus, we have a prediction method for acetonitrile pK(a) with the intercept and the slope as the only adjusted parameters. Furthermore, the pK(a) values of CH acids yielding large anions with delocalized charge can be predicted with a rmse of 1.12 pK(a) units using the theoretical values of slope and intercept resulting in truly ab initio pK(a) prediction. In contrast to our previous findings on aqueous acidity predictions the slope of the experimental pK(a) versus theoretical DeltaG(diss) was found to match the theoretical value 1/RT ln (10) very well. The predictivity of the presented method is general and is not restricted to certain compound classes. However, a systematic correction of -7.5 kcal mol(-1) is required for compounds that do not allow electron-delocalization in the dissociated anion. The prediction model was tested on a diverse test set of 129 complex multifunctional compounds from various sources, reaching a root mean square deviation of 2.10 pK(a) units. PMID:18727157

  1. The 3 Rs of Stroke Biology: Radial, Relayed, and Regenerative.

    PubMed

    Carmichael, S Thomas

    2016-04-01

    Stroke not only causes initial cell death, but also a limited process of repair and recovery. As an overall biological process, stroke has been most often considered from the perspective of early phases of ischemia, how these inter-relate and lead to expansion of the infarct. However, just as the biology of later stages of stroke becomes better understood, the clinical realities of stroke indicate that it is now more a chronic disease than an acute killer. As an overall biological process, it is now more important to understand how early cell death leads to the later, limited recovery so as develop an integrative view of acute to chronic stroke. This progression from death to repair involves sequential stages of primary cell death, secondary injury events, reactive tissue progenitor responses, and formation of new neuronal circuits. This progression is radial: from the tissue that suffers the infarct secondary injury signals, including free radicals and inflammatory cytokines, radiate out from the stroke core to trigger later regenerative events. Injury and repair processes occur not just in the local stroke site, but are also triggered in the connected networks of neurons that had existed in the stroke center: damage signals are relayed throughout a brain network. From these relayed, distributed damage signals, reactive astrocytosis, inflammatory processes, and the formation of new connections occur in distant brain areas. In short, emerging data in stroke cell death studies and the development of the field of stroke neural repair now indicate a continuum in time and in space of progressive events that can be considered as the 3 Rs of stroke biology: radial, relayed, and regenerative. PMID:26602550

  2. Cephalopods in neuroscience: regulations, research and the 3Rs.

    PubMed

    Fiorito, Graziano; Affuso, Andrea; Anderson, David B; Basil, Jennifer; Bonnaud, Laure; Botta, Giovanni; Cole, Alison; D'Angelo, Livia; De Girolamo, Paolo; Dennison, Ngaire; Dickel, Ludovic; Di Cosmo, Anna; Di Cristo, Carlo; Gestal, Camino; Fonseca, Rute; Grasso, Frank; Kristiansen, Tore; Kuba, Michael; Maffucci, Fulvio; Manciocco, Arianna; Mark, Felix Christopher; Melillo, Daniela; Osorio, Daniel; Palumbo, Anna; Perkins, Kerry; Ponte, Giovanna; Raspa, Marcello; Shashar, Nadav; Smith, Jane; Smith, David; Sykes, António; Villanueva, Roger; Tublitz, Nathan; Zullo, Letizia; Andrews, Paul

    2014-03-01

    Cephalopods have been utilised in neuroscience research for more than 100 years particularly because of their phenotypic plasticity, complex and centralised nervous system, tractability for studies of learning and cellular mechanisms of memory (e.g. long-term potentiation) and anatomical features facilitating physiological studies (e.g. squid giant axon and synapse). On 1 January 2013, research using any of the about 700 extant species of "live cephalopods" became regulated within the European Union by Directive 2010/63/EU on the "Protection of Animals used for Scientific Purposes", giving cephalopods the same EU legal protection as previously afforded only to vertebrates. The Directive has a number of implications, particularly for neuroscience research. These include: (1) projects will need justification, authorisation from local competent authorities, and be subject to review including a harm-benefit assessment and adherence to the 3Rs principles (Replacement, Refinement and Reduction). (2) To support project evaluation and compliance with the new EU law, guidelines specific to cephalopods will need to be developed, covering capture, transport, handling, housing, care, maintenance, health monitoring, humane anaesthesia, analgesia and euthanasia. (3) Objective criteria need to be developed to identify signs of pain, suffering, distress and lasting harm particularly in the context of their induction by an experimental procedure. Despite diversity of views existing on some of these topics, this paper reviews the above topics and describes the approaches being taken by the cephalopod research community (represented by the authorship) to produce "guidelines" and the potential contribution of neuroscience research to cephalopod welfare. PMID:24385049

  3. Pioneering Better Science through the 3Rs: An Introduction to the National Centre for the Replacement, Refinement, and Reduction of Animals in Research (NC3Rs)

    PubMed Central

    Burden, Natalie; Chapman, Kathryn; Sewell, Fiona; Robinson, Vicky

    2015-01-01

    The National Centre for the Replacement, Refinement, and Reduction of Animals in Research (NC3Rs) is an independent scientific organization that is based in the United Kingdom, which was set up by the government to lead the discovery and application of new technologies and approaches that minimize the use of animals in research and improve animal welfare. The NC3Rs uses a range of strategies to improve and advance science through application of the 3Rs. These include funding basic research, open innovation (CRACK IT), and programs run by inhouse scientists. We present several case studies from the NC3Rs portfolio, featuring asthma research, the use of nonhuman primates in monoclonal antibody development, and CRACK IT. Finally, we anticipate the future, as we use our experience to move into new research fields and expand toward international collaboration. Here we highlight how equipping scientists with relevant and emerging 3Rs tools can help overcome the challenges and limitations of the use of animals in research to the benefit of the whole bioscience community. PMID:25836967

  4. Combinations of 148 navigation stars and the star tracker

    NASA Technical Reports Server (NTRS)

    Duncan, R.

    1980-01-01

    The angular separation of all star combinations for 148 nav star on the onboard software for space transportation system-3 flight and following missions is presented as well as the separation of each pair that satisfies the viewing constraints of using both star trackers simultaneously. Tables show (1) shuttle star catalog 1980 star position in M 1950 coordinates; (2) two star combination of 148 nav stars; and (3) summary of two star-combinations of the star tracker 5 deg filter. These 148 stars present 10,875 combinations. For the star tracker filters of plus or minus 5 deg, there are 875 combinations. Formalhaut (nav star 26) has the best number of combinations, which is 33.

  5. Association between miR-125a rs12976445 and survival in breast cancer patients

    PubMed Central

    Jiao, Lianghe; Zhang, Jiaxin; Dong, Yuanyuan; Duan, Bensong; Yu, Hong; Sheng, Haihui; Huang, Junxing; Gao, Hengjun

    2014-01-01

    MicroRNAs (miRNAs) act as an oncogene or a tumor suppressor by negatively regulating target genes. Genetic variants in miRNA genes confer susceptibility to cancer and risk of death in cancer patients. The aim of this study was to investigate whether miRNA polymorphisms were associated with survival in breast cancer patients. Five miRNA polymorphisms (miR-26a1 rs7372209, miR-125a rs12976445, miR-218 rs11134527, miR-423 rs6505162, and miR-608 rs4919510) were genotyped in 196 breast cancer patients. We found that miR-125a rs12976445 was significantly associated with survival in codominant, recessive, and dominant models. However, only association under the codominant model remained significant after adjustment for lymph node metastasis, TNM stage, estrogen receptor, and progesterone receptor. Furthermore, this effect remained in stratification analysis. In conclusion, our results provide evidence that miR-125a rs12976445 may serve as a prognostic biomarker for breast cancer. Further large-scale studies are required to confirm these findings. PMID:25628797

  6. TERT promoter mutations and rs2853669 polymorphism: prognostic impact and interactions with common alterations in glioblastomas.

    PubMed

    Nencha, Umberto; Rahimian, Amithys; Giry, Marine; Sechi, Andrea; Mokhtari, Karima; Polivka, Marc; Schmitt, Yohann; Di Stefano, Anna-Luisa; Alentorn, Agusti; Labussire, Marianne; Sanson, Marc

    2016-02-01

    TERT promoter (TERTp) mutation is the most common mutation in glioblastomas. It creates a putative binding site for Ets/TCF transcription factors, enhancing telomerase expression and activity, whereas the rs2853669 variant disrupts another Ets/TCF binding. We explore here the interaction between these two alterations, tumor genomic profile and the impact on prognosis. The TERTp and rs2853669 statuses were determined and confronted with the outcome and molecular profile, i.e., loss of chromosome 10q, CDKN2A deletion, IDH mutation, EGFR amplification, MGMT promoter methylation. 651 glioblastomas were selected (sex ratio=1.35, median age 60.4years, median survival 13.5months). The TERTp mutation found in 481 patients (74%) was independent from rs2853669 genotypes. TERTp mutation, but not rs2853669 status, was associated with older age (61.4 vs. 52.8years). rs2853669 status had no impact on overall survival (OS) either in mutated TERTp or wild-type TERTp. Neither rs2736100 (TERT, 5q15.33) nor rs192011116 (TERC, 3q26.2) status had any impact on survival or showed any association with a TERTp mutation. The TERTp mutation was associated with EGFR amplification chromosome 10q loss, CDKN2A deletion and IDH wt. EGFR amplification was associated with a better outcome in TERTp mutated GBM, and a worse outcome in TERTp WT. This study-the largest analyzing the TERTp mutation and the rs2853669 polymorphism-fails to find any prognostic impact of rs2853669. It confirms the dual prognostic impact of EGFR amplification depending on TERTp status. PMID:26608520

  7. The CHRNA3 rs578776 Variant is Associated with an Intrinsic Reward Sensitivity Deficit in Smokers

    PubMed Central

    Robinson, Jason D.; Versace, Francesco; Lam, Cho Y.; Minnix, Jennifer A.; Engelmann, Jeffrey M.; Cui, Yong; Karam-Hage, Maher; Shete, Sanjay S.; Tomlinson, Gail E.; Chen, Tina T.-L.; Wetter, David W.; Green, Charles E.; Cinciripini, Paul M.

    2013-01-01

    A compromised brain reward system has been postulated as a key feature of drug dependence. We examined whether several polymorphisms of genes found to regulate nicotinic acetylcholine receptor (nAChR) and dopamine expression were related to an intrinsic reward sensitivity (IRS) deficit we previously identified among a subgroup of smokers using event-related potentials (ERPs). We examined genetic polymorphisms within the CHRNA5-A3-B4 gene cluster (CHRNA3 rs578776, CHRNA5 rs16969968, LOC123688 rs8034191, and CHRNA3 rs1051730), the ANKK1 gene (rs1800497), and the D2 dopamine receptor gene (DRD2 rs1079597, DRD2 rs1799732) from 104 smokers of European ancestry in a smoking cessation trial. Prior to treatment, we recorded ERPs evoked by emotional (both pleasant and unpleasant), neutral, and cigarette-related pictures. Smokers were assigned to two groups (IRS+/IRS−) based on the amplitude of the late positive potential (LPP) component to the pictures, a neural marker of motivational salience. Smokers (n = 42) with blunted brain responses to intrinsically rewarding (pleasant) pictures and enhanced responses to cigarette pictures were assigned to the IRS− group, while smokers (n = 62) with the opposite pattern of LPP responding were assigned to the IRS+ group. Carriers of the protective minor T allele (T/T, C/T) of the CHRNA3 rs578776 were less likely to be members of the IRS− group than those homozygous for the at-risk C allele (C/C). The CHRNA3 rs578776 polymorphism did not differ on questionnaires of nicotine dependence, depressed mood, or trait affective disposition and did not predict abstinence at 6 months after the quit date. These results suggest that polymorphisms of genes influencing nAChR expression are related to an endophenotype of reward sensitivity in smokers. PMID:24065931

  8. Contribution of TIMP4 rs3755724 polymorphism to susceptibility to focal epilepsy in Malaysian Chinese.

    PubMed

    Haerian, Batoul Sadat; Sha'ari, Hidayati Mohd; Fong, Choong Yi; Tan, Hui Jan; Wong, Sau Wei; Ong, Lai Choo; Raymond, Azman Ali; Tan, Chong Tin; Mohamed, Zahurin

    2015-01-15

    Neuroinflammation can damage the brain and plays a critical role in the pathophysiology of epilepsy. Tissue inhibitor of metalloproteinase 4 (TIMP4) is an inflammation-induced apoptosis and matrix turnover factor involved in several neuronal disorders and inflammatory diseases. Evidence has shown linkage disequilibrium between rs3755724 (-55C/T) of this gene with synapsin 2 (SYN2) rs3773364 and peroxisome proliferator-activated G receptor (PPARG) rs2920502 loci, which contribute to epilepsy in Caucasians. The aim of this study was to examine the association of these loci alone or their haplotypes with the risk of epilepsy in the Malaysian population. Genomic DNA of 1241 Malaysian Chinese, Indian, and Malay subjects (670 patients with epilepsy and 571 healthy individuals) was genotyped for the candidate loci by using the Sequenom MassArray method. Allele and genotype association of rs3755724 with susceptibility to epilepsy was significant in the Malaysian Chinese with focal epilepsy under codominant and dominant models (C vs. T: 1.5 (1.1-2.0), p=0.02; CT vs. TT: 1.8 (1.2-2.8), p=0.007 and 1.8 (1.2-2.7), p=0.006, respectively). The T allele and the TT genotype were more common in patients than in controls. No significant association was found between rs2920502 and rs3773364-rs3755724-rs2920502 haplotypes for susceptibility to epilepsy in each ethnicity. This study provides evidence that the promoter TIMP4 rs3755724 is a new focal epilepsy susceptibility variant that is plausibly involved in inflammation-induced seizures in Malaysian Chinese. PMID:25595263

  9. Equations of State in the Hartle-Thorne Model of Neutron Stars Selecting Acceptable Variants of the Resonant Switch Model of Twin HF QPOs in the Atoll Source 4U 1636-53

    NASA Astrophysics Data System (ADS)

    Stuchlìk, Z.; Urbanec, M.; Kotrlovà, A.; Török, G.; Goluchovà, K.

    2015-06-01

    The Resonant Switch (RS) model of twin high-frequency quasi-periodic oscillations (HF QPOs) observed in neutron star binary systems, based on switch of the twin oscillations at a resonant point, has been applied to the atoll source 4U 1636-53 under assumption that the neutron star exterior can be approximated by the Kerr geometry. Strong restrictions of the neutron star parameters M (mass) and a (spin) arise due to fitting the frequency pairs admitted by the RS model to the observed data in the regions related to the resonant points. The most precise variants of the RS model are those combining the relativistic precession frequency relations with their modifications. Here, the neutron star mass and spin estimates given by the RS model are confronted with a variety of equations of state (EoS) governing structure of neutron stars in the framework of the Hartle-Thorne theory of rotating neutron stars applied for the observationally given rotation frequency frot≍580 Hz (or alternatively frot≍290 Hz) of the neutron star in 4U 1636-53. It is shown that only two variants of the RS model based on the Kerr approximation are compatible with two EoS applied in the Hartle-Thorne theory for frot≍580 Hz, while no variant of the RS model is compatible for frot≍290 Hz. The two compatible variants of the RS model are those giving the best fits of the observational data. However, a self-consistency test by fitting the observational data to the RS model with oscillation frequencies governed by the Hartle-Thorne geometry described by three spacetime parameters M,a and (quadrupole moment) q related by the two available EoS puts strong restrictions. The test admits only one variant of the RS model of twin HF QPOs for the Hartle-Thorne theory with the EoS predicting the parameters of the neutron star M≍2.10 M⊙, a≍0.208, and q/a2≍1.77.

  10. Identifying Young, Nearby Stars

    NASA Technical Reports Server (NTRS)

    Webb, Rich; Song, Inseok; Zuckerman, Ben; Bessell, Mike

    2001-01-01

    Young stars have certain characteristics, e.g., high atmospheric abundance of lithium and chromospheric activity, fast rotation, distinctive space motion and strong X-ray flux compared to that of older main sequence stars. We have selected a list of candidate young (<100Myr) and nearby (<60pc) stars based on their space motion and/or strong X-ray flux. To determine space motion of a star, one needs to know its coordinates (RA, DEC), proper motion, distance, and radial velocity. The Hipparcos and Tycho catalogues provide all this information except radial velocities. We anticipate eventually searching approx. 1000 nearby stars for signs of extreme youth. Future studies of the young stars so identified will help clarify the formation of planetary systems for times between 10 and 100 million years. Certainly, the final output of this study will be a very useful resource, especially for adaptive optics and space based searches for Jupiter-mass planets and dusty proto-planetary disks. We have begun spectroscopic observations in January, 2001 with the 2.3 m telescope at Siding Spring Observatory (SSO) in New South Wales, Australia. These spectra will be used to determine radial velocities and other youth indicators such as Li 6708A absorption strength and Hydrogen Balmer line intensity. Additional observations of southern hemisphere stars from SSO are scheduled in April and northern hemisphere observations will take place in May and July at the Lick Observatory of the University of California. AT SSO, to date, we have observed about 100 stars with a high resolution spectrometer (echelle) and about 50 stars with a medium spectral resolution spectrometer (the "DBS"). About 20% of these stars turn out to be young stars. Among these, two especially noteworthy stars appear to be the closest T-Tauri stars ever identified. Interestingly, these stars share the same space motions as that of a very famous star with a dusty circumstellar disk--beta Pictoris. This new finding better constrains the age of beta Pictoris to be approx. 10 Myr.

  11. GLOBAL STAR FORMATION REVISITED

    SciTech Connect

    Silk, Joseph; Norman, Colin E-mail: norman@stsci.edu

    2009-07-20

    A general treatment of disk star formation is developed from a dissipative multiphase model, with the dominant dissipation due to cloud collisions. The Schmidt-Kennicutt (SK) law emerges naturally for star-forming disks and starbursts. We predict that there should be an inverse correlation between Tully-Fisher law and SK law residuals. The model is extended to include a multiphase treatment of supernova feedback that leads to a turbulent pressure-regulated generalization of the star formation law and is applicable to gas-rich starbursts. Enhanced pressure, as expected in merger-induced star formation, enhances star formation efficiency. An upper limit is derived for the disk star formation rate in starbursts that depends on the ratio of global ISM to cloud pressures. We extend these considerations to the case where the interstellar gas pressure in the inner galaxy is dominated by outflows from a central active galactic nucleus (AGN). During massive spheroid formation, AGN-driven winds trigger star formation, resulting in enhanced supernova feedback and outflows. The outflows are comparable to the AGN-boosted star formation rate and saturate in the super-Eddington limit. Downsizing of both SMBH and spheroids is a consequence of AGN-driven positive feedback. Bondi accretion feeds the central black hole with a specific accretion rate that is proportional to the black hole mass. AGN-enhanced star formation is mediated by turbulent pressure and relates spheroid star formation rate to black hole accretion rate. The relation between black hole mass and spheroid velocity dispersion has a coefficient (Salpeter time to gas consumption time ratio) that provides an arrow of time. Highly efficient, AGN-boosted star formation can occur at high redshift.

  12. RS-34 (Peacekeeper Post Boost Propulsion System) Orbital Debris Application Concept Study

    NASA Technical Reports Server (NTRS)

    Esther, Elizabeth A.; Burnside, Christopher G.

    2013-01-01

    The Advanced Concepts Office (ACO) at the NASA Marshall Space Flight Center (MSFC) lead a study to evaluate the Rocketdyne produced RS-34 propulsion system as it applies to an orbital debris removal design reference mission. The existing RS-34 propulsion system is a remaining asset from the de-commissioned United States Air Force Peacekeeper ICBM program; specifically the pressure-fed storable bi-propellant Stage IV Post Boost Propulsion System. MSFC gained experience with the RS-34 propulsion system on the successful Ares I-X flight test program flown in the Ares I-X Roll control system (RoCS). The heritage hardware proved extremely robust and reliable and sparked interest for further utilization on other potential in-space applications. Subsequently, MSFC is working closely with the USAF to obtain all the remaining RS-34 stages for re-use opportunities. Prior to pursuit of securing the hardware, MSFC commissioned the Advanced Concepts Office to understand the capability and potential applications for the RS-34 Phoenix stage as it benefits NASA, DoD, and commercial industry. Originally designed, the RS-34 Phoenix provided in-space six-degrees-of freedom operational maneuvering to deploy multiple payloads at various orbital locations. The RS-34 Concept Study, preceded by a utilization study to understand how the unique capabilities of the RS-34 Phoenix and its application to six candidate missions, sought to further understand application for an orbital debris design reference mission as the orbital debris removal mission was found to closely mimic the heritage RS-34 mission. The RS-34 Orbital Debris Application Concept Study sought to identify multiple configurations varying the degree of modification to trade for dry mass optimization and propellant load for overall capability and evaluation of several candidate missions. The results of the RS-34 Phoenix Utilization Study show that the system is technically sufficient to successfully support all of the missions analyzed. The results and benefits of the RS-34 Orbital Debris Application Concept Study are presented in this paper.

  13. Three-dimensional view based on RS and GIS: three-dimensional simulation of Mount Taishan

    NASA Astrophysics Data System (ADS)

    Song, Xiaoning; Yang, Fengjie; Zhen, Han; Liu, Qiaoxi; Zhang, Fengli

    2000-10-01

    It has not been satisfied with the need of visualization by 2D RS(remote sensing)image. The 3D simulation overlapped with RS image can reflect land forms more directly. This article is to simulate the Mount Taishan, which is world famous natural and cultural heritage, in 3D on the basis of RS and GIS for adapting to the developing of society. First generating DEM, then the TM image is overlaid DEM data and is shown in 3D with the 3D technique of ER mapper. This study takes guidance action on tour planning of Mount Taishan and tourists visiting the Mount Taishan.

  14. Eclipsing Binary Stars in the OGLE-III Fields of the Small Magellanic Cloud

    NASA Astrophysics Data System (ADS)

    Pawlak, M.; Graczyk, D.; Soszyński, I.; Pietrukowicz, P.; Poleski, R.; Udalski, A.; Szymański, M. K.; Kubiak, M.; Pietrzyński, G.; Wyrzykowski, Ł.; Ulaczyk, K.; Kozłowski, S.; Skowron, J.

    2013-09-01

    We present a large sample of eclipsing binary stars detected in the Small Magellanic Cloud fields covering about 14 square degrees that have been monitored for eight years during the third phase of the OGLE survey. This is the largest set of such variables containing 6138 objects, of which 777 are contact and 5361 non-contact binaries. The estimated completeness of this sample is around 82%. We analyze the statistical properties of the sample and present selected interesting objects: 32 systems having eccentric orbit with visible apsidal motion, one Transient Eclipsing Binary, ten RS CVn type stars, 22 still unexplained Double-Periodic Variable stars, and 15 candidates for doubly eclipsing quadruple systems. Based on the OGLE-III proper motions, we classified 47 binaries from our sample as foreground Galactic stars. We also list candidates suitable for the SMC distance determination.

  15. Stars and Flowers, Flowers and Stars

    NASA Astrophysics Data System (ADS)

    Minti, Hari

    2012-12-01

    The author, a graduated from the Bucharest University (1964), actually living and working in Israel, concerns his book to variable stars and flowers, two domains of his interest. The analogies includes double stars, eclipsing double stars, eclipses, Big Bang. The book contains 34 chapters, each of which concerns various relations between astronomy and other sciences and pseudosciences such as Psychology, Religion, Geology, Computers and Astrology (to which the author is not an adherent). A special part of the book is dedicated to archeoastronomy and ethnoastronomy, as well as to history of astronomy. Between the main points of interest of these parts: ancient sanctuaries in Sarmizegetusa (Dacia), Stone Henge(UK) and other. The last chapter of the book is dedicated to flowers. The book is richly illustrated. It is designed for a wide circle of readers.

  16. Star Trek in the Schools

    ERIC Educational Resources Information Center

    Journal of Aerospace Education, 1977

    1977-01-01

    Describes specific educational programs for using the Star Trek TV program from kindergarten through college. For each grade level lesson plans, ideas for incorporating Star Trek into future classes, and reports of specific programs utilizing Star Trek are provided. (SL)

  17. Project Jelly-Fish: B.R.N.O. Observations of Semiregular Variable Stars

    NASA Astrophysics Data System (ADS)

    Hajek, P.

    2006-06-01

    Brno Regional Network of Observers (BRNO) is a group which prefers to observe eclipsing binary stars. A team called the Jelly-Fish has been formed within BRNO for the purpose of observing variable stars other than eclipsing binaries. The observations by Jelly-Fish members are predominantly visual; CCD observing has started only recently and such observations are not yet included in our statistics. Jelly-Fish has about twenty members at this moment. This paper presents preliminary results based on Jelly-Fish observations of S Camelopardalis, AU Camelopardalis, WZ Cassiopeiae, RS Cygni, T Persei, RU Persei, and R Ursae Minoris.

  18. Genome-wide association study-identified SNPs (rs3790844, rs3790843) in the NR5A2 gene and risk of pancreatic cancer in Japanese

    PubMed Central

    Ueno, Makoto; Ohkawa, Shinichi; Morimoto, Manabu; Ishii, Hiroshi; Matsuyama, Masato; Kuruma, Sawako; Egawa, Naoto; Nakao, Haruhisa; Mori, Mitsuru; Matsuo, Keitaro; Hosono, Satoyo; Nojima, Masanori; Wakai, Kenji; Nakamura, Kozue; Tamakoshi, Akiko; Takahashi, Mami; Shimada, Kazuaki; Nishiyama, Takeshi; Kikuchi, Shogo; Lin, Yingsong

    2015-01-01

    We genotyped 2 SNPs (rs3790844 T/C and rs3790843 G/A) in the NR5A2 gene that were identified in a genome-wide association study (GWAS) of pancreatic cancer in populations of mainly European ancestry, and we examined their associations with pancreatic cancer risk in a case-control study of 360 patients and 400 control subjects in Japan. Unconditional logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). The SNPs were in linkage disequilibrium (r2 = 0.80). For rs3790843, the multivariable-adjusted OR was 0.75 (95% CI: 0.41–1.36) and 0.60 (95%CI: 0.33–1.08) for subjects with the AG and AA genotype, respectively, compared to subjects with the GG genotype. The per allele OR was 0.78 (0.62–0.99) (P = 0.046). For rs3790844, the multivariable-adjusted OR was 0.65 (95% CI: 0.37–1.14) and 0.47 (95%CI: 0.27–0.83) for subjects with the CT and CC genotype, respectively, compared to subjects with the TT genotype. The per allele OR was 0.70 (0.56–0.89) (P = 0.003). Our case-control study found that rs3790843 and rs3790844 in the NR5A2 gene are associated with pancreatic cancer risk in Japanese subjects. The direction of association is consistent with the prior findings from GWASs. PMID:26592175

  19. Role of TLR4  rs4986790A>G and rs4986791C>T Polymorphisms in the Risk of Inflammatory Bowel Disease

    PubMed Central

    Ao, Ran; Wang, Ying; Zhnag, Dao-Rong; Du, Ya-Qi

    2015-01-01

    Objective. The present meta-analysis investigated the contribution of TLR4 rs4986790A>G and rs4986791C>T genetic polymorphisms in increasing the risk of inflammatory bowel disease (IBD). Methods. Databases were searched using a combination of keywords related to TLR4 and IBD. Relevant studies were selected based on strict inclusion and exclusion criteria. Meta-analysis of the data extracted from the selected studies was performed using CMA 2.0 statistical analysis software. Results. Out of the 70 studies retrieved by database search, only 13 studies were eligible for inclusion in this meta-analysis and these 13 studies contained a total number of 4409 IBD patients and 5693 healthy controls. The meta-analysis results demonstrated that TLR4 rs4986790A>G polymorphism is associated with an increased risk of IBD (allele model: OR = 1.268, 95% CI = 1.124~1.431, and P < 0.001; dominant model: OR = 1.240, 95% CI = 1.090~1.409, and P = 0.001). Similarly, TLR4 rs4986791C>T polymorphism also conferred an increased risk of IBD (allele model: OR = 1.259, 95% CI = 1.092~1.453, and P = 0.002; dominant model: OR = 1.246, 95% CI = 1.072~1.447, and P = 0.004). Conclusion. Our meta-analysis results demonstrate that TLR4 rs4986790A>G and rs4986791C>T genetic polymorphisms are associated with the etiopathogenesis of IBD. PMID:26089865

  20. General relativity and neutron stars

    NASA Astrophysics Data System (ADS)

    Yakovlev, D. G.

    2016-01-01

    General Relativity affects all major aspects of neutron star structure and evolution including radiation from the surface, neutron star models, evolution in compact binaries. It is widely used for neutron star mass measurements and for studying properties of superdense matter in neutron stars. Observations of neutron stars help testing General Relativity and planning gravitational wave experiments. No deviations from Einstein Theory of Gravity have been detected so far from observations of neutron stars.

  1. The Violent Neutron Star

    NASA Astrophysics Data System (ADS)

    Watts, A. L.

    2012-12-01

    Neutron stars enable us to study both the highest densities and the highest magnetic fields in the known Universe. In this article I review what can be learned about such fundamental physics using magnetar bursts. Both the instability mechanisms that trigger the bursts, and the subsequent dynamical and radiative response of the star, can be used to explore stellar and magnetospheric structure and composition.

  2. Science through ARts (STAR)

    ERIC Educational Resources Information Center

    Densmore, Marycay; Kolecki, Joseph C.; Miller, Allan; Petersen, Ruth; Terrell, Mike

    2005-01-01

    Science Through ARts (STAR) is a free, international, cross-curricular program thematically aligned with "The Vision for Space Exploration," a framework of goals and objectives published by NASA in February 2004. Through the STAR program, students in grades 5 through 12 are encouraged to apply their knowledge in creative ways as they approach a

  3. Science through ARts (STAR)

    ERIC Educational Resources Information Center

    Densmore, Marycay; Kolecki, Joseph C.; Miller, Allan; Petersen, Ruth; Terrell, Mike

    2005-01-01

    Science Through ARts (STAR) is a free, international, cross-curricular program thematically aligned with "The Vision for Space Exploration," a framework of goals and objectives published by NASA in February 2004. Through the STAR program, students in grades 5 through 12 are encouraged to apply their knowledge in creative ways as they approach a…

  4. Neutron Star Cooling: II

    NASA Astrophysics Data System (ADS)

    Tsuruta, Sachiko

    It was more than 70 years ago when Baade and Zwicky [3] speculated that an exotic star consisting mostly of neutrons, now known as a neutron star, may be formed when a normal star collapses through a supernova explosion. During the subsequent years in the 1930s several theorists, including Oppenheimer and Volkoff [35], discussed the properties of neutron stars. However, it was not until the late 1950s to the early 1960s, when curiosity on such a hypothetical object revived [11,73]. As far as I am aware Cameron [11] is the first author who discussed thermodynamic problems of neutron stars. This article's author chose to explore this problem as one of the projects on neutron stars as her PhD thesis [59]. The research started as a purely theoretical endeavor, but before the calculations were completed we learned of the discovery of the first Galactic X-ray source Sco X-1, which was soon followed by the second such Galactic X-ray source detection, this time in the Crab supernova remnant [15]. It was immediately suggested by several theorists [19, 59, 66] that these strong X-ray sources might be neutron stars, because if these X-rays are blackbody radiation as expected, the radius of the emitting region has to be as small as 10 km (because the temperature is so high), just the correct size predicted for a neutron star.1

  5. Observing Double Stars

    NASA Astrophysics Data System (ADS)

    Genet, Russell M.; Fulton, B. J.; Bianco, Federica B.; Martinez, John; Baxter, John; Brewer, Mark; Carro, Joseph; Collins, Sarah; Estrada, Chris; Johnson, Jolyon; Salam, Akash; Wallen, Vera; Warren, Naomi; Smith, Thomas C.; Armstrong, James D.; McGaughey, Steve; Pye, John; Mohanan, Kakkala; Church, Rebecca

    2012-05-01

    Double stars have been systematically observed since William Herschel initiated his program in 1779. In 1803 he reported that, to his surprise, many of the systems he had been observing for a quarter century were gravitationally bound binary stars. In 1830 the first binary orbital solution was obtained, leading eventually to the determination of stellar masses. Double star observations have been a prolific field, with observations and discoveries - often made by students and amateurs - routinely published in a number of specialized journals such as the Journal of Double Star Observations. All published double star observations from Herschel's to the present have been incorporated in the Washington Double Star Catalog. In addition to reviewing the history of visual double stars, we discuss four observational technologies and illustrate these with our own observational results from both California and Hawaii on telescopes ranging from small SCTs to the 2-meter Faulkes Telescope North on Haleakala. Two of these technologies are visual observations aimed primarily at published "hands-on" student science education, and CCD observations of both bright and very faint doubles. The other two are recent technologies that have launched a double star renaissance. These are lucky imaging and speckle interferometry, both of which can use electron-multiplying CCD cameras to allow short (30 ms or less) exposures that are read out at high speed with very low noise. Analysis of thousands of high speed exposures allows normal seeing limitations to be overcome so very close doubles can be accurately measured.

  6. Science Through ARts (STAR)

    NASA Technical Reports Server (NTRS)

    Kolecki, Joseph; Petersen, Ruth; Williams, Lawrence

    2002-01-01

    Science Through ARts (STAR) is an educational initiative designed to teach students through a multidisciplinary approach to learning. This presentation describes the STAR pilot project, which will use Mars exploration as the topic to be integrated. Schools from the United Kingdom, Japan, the United States, and possibly eastern Europe are expected to participate in the pilot project.

  7. Populations of Carbon Stars

    NASA Astrophysics Data System (ADS)

    Lloyd Evans, T.

    2011-09-01

    Carbon stars in the Galaxy do not constitute a single family, but may be divided over several types with distinctive spectroscopic and photometric properties. A subtype of the N stars, characterised by high velocities and weak CN bands, may have been captured by the Milky Way from a cannibalised dwarf galaxy.

  8. Computerized Star Map.

    ERIC Educational Resources Information Center

    Shooman, Andrew

    1982-01-01

    A program written for the 16K Level II TRS-80 computer that prints a star map, using various mathematical formulas to compute positions of the stars and the moon and displays them on terminals, is discussed. Some relevant astronomical background and terminology are covered in order to aid understanding. (MP)

  9. Associations of CYP2E1 rs2031920 and rs3813867 polymorphisms with colorectal cancer risk: a systemic review and meta-analysis.

    PubMed

    Peng, Hui; Xie, Shang-Kui; Huang, Mei-Jin; Ren, Dong-Lin

    2013-08-01

    Cytochrome P450 2E1 (CYP2E1) is a natural enzyme involved in the metabolic activation of many carcinogens, and the functional polymorphisms in the CYP2E1 gene might have impacts on colorectal cancer risk. Many studies were published to assess the associations of CYP2E1 rs2031920 and rs3813867 polymorphisms with colorectal cancer risk, but no consistent findings were reported. A systemic review and meta-analysis of eligible studies was performed to comprehensively assess the associations above. Odds ratios (ORs) with 95 % confidence interval (95 % CIs) were used to assess the strength of the associations. Seventeen studies from 15 publications with 17,082 individuals were finally included into this meta-analysis. Meta-analysis of the 13 studies on CYP2E1 rs2031920 polymorphism showed that there was a significant association between CYP2E1 rs2031920 polymorphism and colorectal cancer risk under two genetic models (c2 versus c1: OR = 1.19, 95 % CI 1.03-1.37, P = 0.022; c2c2/c2c1 versus c1c1: OR = 1.16, 95 % CI 1.00-1.35, P = 0.046). Meta-analysis of those four case-control studies on CYP2E1 rs3813867 polymorphism showed that there was no significant association between CYP2E1 rs3813867 polymorphism and colorectal cancer risk under all contrast models (c2 versus c1: OR = 0.96, 95 % CI 0.80-1.16, P = 0.672; c2c2 versus c1c1: OR = 1.26, 95 % CI 0.43-3.67, P = 0.672; c2c2/c1c2 versus c1c1: OR = 0.95, 95 % CI 0.78-1.16, P = 0.114; and c2c2 versus c1c2/c1c1: OR = 1.17, 95 % CI 0.41-3.36, P = 0.775). Therefore, the findings from this meta-analysis suggest that CYP2E1 rs2031920 polymorphism is associated with colorectal cancer risk, but CYP2E1 rs3813867 polymorphism is not associated with colorectal cancer risk. In addition, more well-designed studies with large sample size are needed to provide a more precise evaluation on the associations above. PMID:23595220

  10. Association Study between Coronary Artery Disease and rs1333049 and rs10757274 Polymorphisms at 9p21 Locus in South-West Iran

    PubMed Central

    Foroughmand, Ali Mohammad; Nikkhah, Emad; Galehdari, Hamid; Jadbabaee, Mohammad Hossin

    2015-01-01

    Objective Coronary artery disease (CAD) is a multi-factorial and heterogenic disease with atherosclerosis plaques formation in internal wall of coronary artery. Plaque formation results to limitation of the blood reaching to myocardium leading to appearance of some problems, such as ischemia, sudden thrombosis veins and myocardial infarction (MI). Several environmental and genetic factors are involved in prevalence and incident of CAD as follows: hypertension, high low density lipoprotein-cholesterol (LDL-C), age, diabetes mellitus, family history of early-onset heart disease and smoking. According to genome wide association studies (GWAS), five polymorphisms in the 9p21 locus seem to be associated with the CAD. We aimed to evaluate the remarkable association of two polymorphisms at 9p21 locus, rs1333049 and rs10757274, with CAD. Materials and Methods This experimental study was conducted in Golestan, Aria Hospitals and Genetics Lab of Shahid Chamran University in the city of Ahvaz, Iran, in 2010- 2011. The collected blood samples belonging to 170 CAD patients (case group) and 100 healthy individuals (control group) were analyzed by tetra-primer amplification refractory mutation system (ARMS)-polymerase chain reaction (PCR) technique. The results were analyzed using software package used for statistical analysis (SPSS; SPSS Inc., USA) version 16. A value of p<0.05 and an odd ratio (OR) with 95% confidence intervals (CI) were considered significant. Results The frequencies of CC, CG and GG genotypes for rs1333049 polymorphism in patients were 18.2, 65.3 and 16.5%, while in controls, the related values were 25, 67 and 8%, respectively. GG genotypes of rs1333049 polymorphism in CAD patients were more than control cases (OR: 0.354, 95%CI: 0.138-0.912, p=0.032). The frequencies of AA, AG and GG genotypes for rs10757274 in CAD patients were 8.2, 58.3 and 33.5%, while in controls, the related values were 35, 63 and 2%, respectively. GG Genotype in rs10757274 polymorphism in CAD patients was found more than control cases (OR: 0.014, 95% CI: 0.003 -0.065, p=0.0001). Conclusion The rs1333049 polymorphism at 9p21 locus shows a weak association with CAD, whereas rs10757274 polymorphism reveals a significant association with CAD. These variants may help the identification of patients with increased risk for coronary artery disease. PMID:25870838

  11. Associations between FAS rs2234767 and FASL rs763110 polymorphisms and the risk of lung cancer: a meta-analysis of 39,736 subjects

    PubMed Central

    Yu, Xiongjie; Li, Yanli; Yu, Yuandong; Lei, Jinhua; Wan, Guoxing; Cao, Fengjun

    2016-01-01

    Background Previous studies have investigated the associations between the common polymorphisms in FAS/FASL genes and lung cancer risk; however, the results remain inconsistent and inconclusive. Hence, we performed a meta-analysis to reassess the relationships between FAS rs2234767 and FASL rs763110 polymorphisms and the risk of lung cancer. Methods Eligible studies retrieved by an electronic search were pooled to calculate the strength of the associations using the odds ratio (OR) and 95% confidence interval (95% CI). Results A total of 13 case–control studies involving 39,736 subjects (9,237 cases and 10,838 controls on FAS rs2234767 and 8,957 cases and 10,704 controls on FASL rs763110) were included in the meta-analysis. The results showed a significant association between FAS rs2234767 polymorphism and increased risk of lung cancer (A vs G: OR =1.07, 95% CI =1.01–1.13; AA vs GG: OR =1.23, 95% CI =1.06–1.43; AA vs GA + GG: OR =1.24, 95% CI =1.08–1.43). Similar association was also observed in Asian population (AA vs GA + GG: OR =1.30, 95% CI =1.01–1.67) and in the studies with large sample size (A vs G: OR =1.07, 95% CI =1.00–1.14; AA vs GG: OR =1.30, 95% CI =1.07–1.58). However, no significant association between FASL rs763110 polymorphism and lung cancer risk was found other than in the Asian population (CC vs TC + TT: OR =1.35, 95% CI =1.01–1.80). Conclusion The meta-analysis indicated that FAS rs2234767 polymorphism was significantly associated with an increased risk of lung cancer and FASL rs763110 polymorphism may not contribute to susceptibility to lung cancer other than in Asian population. PMID:27103831

  12. The onset of chromospheric activity among the A and F stars

    NASA Technical Reports Server (NTRS)

    Simon, Theodore; Landsman, Wayne

    1991-01-01

    Results are reported from a search for an upper boundary for the onset of main-sequence star activity based on a quest for high-temperature UV line emission in a large collection of IUE spectra. It is shown that strong chromospheric emission is common among early F dwarf and subgiant stars. At its brightest, the emission is equal to that of the most active solar-type stars and is exceeded only by that of the spotted RS CVn and BY Dra variables. It is suggested that the emission from the main-sequence stars reaches a peak near B-V = 0.28, in the vicinity of spectral type F0 V, before it declines to lower flux levels among the late A stars. Emission is seen in some dwarf stars as early as B-V = 0.25. It is demonstrated that the C II emission of stars earlier than the spectral type F5 is uncorrelated with rotation. Previous findings that the coronal X-ray:chromospheric UV flux ratio is lower for stars earlier than spectral type F5 than for those later than F5 are confirmed.

  13. A VLA radio-continuum survey of a sample of confirmed and marginal barium stars

    NASA Technical Reports Server (NTRS)

    Drake, Stephen A.; Simon, Theodore; Linsky, Jeffrey L.

    1987-01-01

    Results are reported from a 6-cm VLA survey of five confirmed Ba II stars and eight mild Ba II stars, undertaken to search for evidence of gyrosynchrotron emission or thermal emission from the primary star's wind that is enhanced or photoionized by a white dwarf companion. Of these 13 stars, only Beta UMi was detected as a possible radio source at a flux level of 0.11 mJy (3sigma). The 6-cm radio luminosities (L6) of the other stars are as small as log L6 less than or equal to 14.0 and are an order of magnitude or more lower than the average levels found in RS CVn systems, but are consistent with the L6 upper limits previously found for stars of spectral type similar to the Ba II stars and normal elemental abundances. The upper limit to the radio luminosity for the possible mild Ba II star 56 Peg, when combined with its previously known X-ray luminosity, may provide useful constraints on the various models that have been proposed for this interesting object, once its orbital period is known.

  14. Observing Variable Stars

    NASA Astrophysics Data System (ADS)

    Good, Gerry A.

    Observing variable stars is one of the major contributions amateur astronomers make to science. There are 36,000 variable stars listed in the General Catalogue of Variable Stars, so it is clearly impossible for the limited number of professional observatories to target even the majority of them. That's where amateur astronomers come in - thousands of them turning their telescopes to the sky every night. Variable star observing is the most popular of "real science" activities for amateurs, and Gerry Good's book provides everything needed. The first part of the book provides a highly detailed account of the various classes of variable star, with examples, illustrations and physical descriptions. The second section covers practical aspects of observing, everything from preparation and planning, through observing techniques, to data management and reduction.

  15. Neutron stars - General review

    NASA Technical Reports Server (NTRS)

    Cameron, A. G. W.; Canuto, V.

    1974-01-01

    A review is presented of those properties of neutron stars upon which there is general agreement and of those areas which currently remain in doubt. Developments in theoretical physics of neutron star interiors are summarized with particular attention devoted to hyperon interactions and the structure of interior layers. Determination of energy states and the composition of matter is described for successive layers, beginning with the surface and proceeding through the central region into the core. Problems encountered in determining the behavior of matter in the ultra-high density regime are discussed, and the effects of the magnetic field of a neutron star are evaluated along with the behavior of atomic structures in the field. The evolution of a neutron star is outlined with discussion centering on carbon detonation, cooling, vibrational damping, rotation, and pulsar glitches. The role of neutron stars in cosmic-ray propagation is considered.

  16. Activity Cycles in Stars

    NASA Technical Reports Server (NTRS)

    Hathaway, David H.

    2009-01-01

    Starspots and stellar activity can be detected in other stars using high precision photometric and spectrometric measurements. These observations have provided some surprises (starspots at the poles - sunspots are rarely seen poleward of 40 degrees) but more importantly they reveal behaviors that constrain our models of solar-stellar magnetic dynamos. The observations reveal variations in cycle characteristics that depend upon the stellar structure, convection zone dynamics, and rotation rate. In general, the more rapidly rotating stars are more active. However, for stars like the Sun, some are found to be inactive while nearly identical stars are found to be very active indicating that periods like the Sun's Maunder Minimum (an inactive period from 1645 to 1715) are characteristic of Sun-like stars.

  17. Long-term behaviour of starspots. III - Active longitudes on the long-period RS CVn star HK Lacertae

    NASA Technical Reports Server (NTRS)

    Olah, K.; Hall, D. S.; Henry, G. W.

    1991-01-01

    Thirteen years of photometry were used to study active longitudes on the surface of HK Lacertae. The decaying and forming phenomena of active areas in the years of 1980-1981, 1983-1984, and 1988-1989 are shown. New activity centers suddenly occur near the same orbital phase (0.6) and have lifetimes of several (greater than 6) years. The average rotational period of HK Lac is 24.2852 d; compared to the orbital period of 24.4284 d, this implies a 32 degree/year drift of the active areas on the stellar surface. Two possible interpretations for the period difference are discussed: pseudosynchronism and rigidity of magnetic patterns. The active longitudes on HK Lac are compared with similar phenomena found on the sun.

  18. Dust extinction and intrinsic SEDs of carbon-rich stars. II. The hot carbon stars

    NASA Astrophysics Data System (ADS)

    Bergeat, J.; Knapik, A.; Rutily, B.

    1999-02-01

    The present work is an extension of a recent study by Knapik & Bergeat (\\cite{knapik}, henceforth called Paper I) of the spectral energy distributions (SEDs) of about 300 cool carbon-rich variables and of the interstellar extinction observed on their line of sights. The methods were originally developed for Semi-Regular (SR) and Irregular (L)-variables. Shortly, this is a kind of a pair method making use simultaneously of the whole SED from UV to IR. Our approach is applied here to the galactic carbon-rich giants with bluer SEDs, namely the hot carbon (HC) stars, including many ``constant'' stars and a minority of variables: AC Her a RV Tau star, the R Coronae Borealis (RCB) stars and others. Some HdC (i.e. carbon-rich hydrogen deficient stars) and Ba II stars are also considered. The total number of studied HC stars amounts to about 140. With few exceptions, the colour excesses for interstellar extinction are found in good agreement with the field values from maps published in the literature, taking into account the approximate distances to our stars from HIPPARCOS data (\\cite{esa}, henceforth called ESA) or binarity. We propose a classification scheme with six photometric groups (or boxes: HC0 to HC5) from the bluest to the reddest SEDs. Oxygen-rich SEDs earlier than HC0, are attributed to the hottest stars (AC Her, most RCB-variables and a few others). Previous findings are confirmed of a junction between oxygen-rich and carbon-rich SEDs at spectral type G. The latest (HC5) group is immediately close to the earliest one in Paper I, namely CV1. The sequence of groups then goes regularly from HC0 to CV6. Substantial infrared excesses with respect to our solutions are found in HD 100764 a HC1 carbon star, AC Her a G0g RV Tau star, and the RCB stars classified in either HC or oxygen-groups. The colour excesses at maximum light can usually be attributed to interstellar reddening, with neutral circumstellar (CS) reddening (large grains) or no CS extinction at all on the line of sight (non spherical geometry) as possible explanations. The latter model (disc or patchy distribution through successive puffs) is favoured. Two RCB variables for which we exploit SEDs on a rising branch (V CrA) or minimum light (RS Tel), show CS laws, respectively a selective extinction compatible with small grains and an extinction partly neutral indicative of large grains on the line of sight. This research has made use of the Simbad database operated at CDS, Strasbourg, France.}\\fnmsep\\thanks{Partially based on data from the ESA HIPPARCOS astrometry satellite}\\fnmsep\\thanks{Tables~3 and 4 are only available in electronic form at the CDS via anonymous ftp 130.79.128.5

  19. Preparation and characterization of ketoprofen loaded eudragit RS polymeric nanoparticles for controlled release

    NASA Astrophysics Data System (ADS)

    Anh, Nguyen Tuan; Chi, Nguyen T.; Khai Tran, T.; Tuyen Dao, T. P.; Nhan Le, N. T.; Mau Chien, Dang; Hoai, Nguyen To

    2012-12-01

    Nanospheres containing ketoprofen (Keto) and polymer eudragit RS were prepared using an emulsion solvent evaporation method. The ultrasonic probe (VCX500, vibracell) was used as a tool to disperse oil phase into aqueous phase leading to water/oil emulsion. Nanoparticles were successfully prepared and their morphologies and diameters were confirmed by transmission electron microscope (TEM) and dynamic light scattering (DLS), respectively. The result showed that particles were spherical with submicron size. The particle size was dependent on the RS concentration, emulsification tools and the types of organic solvents. For the encapsulation ability, Keto-loaded RS nanoparticle showed 9.8% of Keto in nanoparticle, which was evaluated by high-performance liquid chromatography (HPLC). Moreover, the drug release behavior of Keto-loaded eudragit RS nanoparticle was also investigated in vitro at pH 7.4 and compared to referential profenid.

  20. Consideration and Checkboxes: Incorporating Ethics and Science into the 3Rs

    PubMed Central

    Landi, Margaret S; Shriver, Adam J; Mueller, Anne

    2015-01-01

    Members of the research community aim to both produce high-quality research and ensure that harm is minimized in animals. The primary means of ensuring these goals are both met is the 3Rs framework of replacement, reduction, and refinement. However, some approaches to the 3Rs may result in a ‘check box mentality’ in which IACUC members, researchers, administrators, and caretakers check off a list of tasks to evaluate a protocol. We provide reasons for thinking that the 3Rs approach could be enhanced with more explicit discussion of the ethical assumptions used to arrive at an approved research protocol during IACUC review. Here we suggest that the notion of moral considerability, and all of the related issues it gives rise to, should be incorporated into IACUC discussions of 3Rs deliberations during protocol review to ensure that animal wellbeing is enhanced within the constraints of scientific investigation. PMID:25836970

  1. Consideration and checkboxes: incorporating ethics and science into the 3Rs.

    PubMed

    Landi, Margaret S; Shriver, Adam J; Mueller, Anne

    2015-03-01

    Members of the research community aim to both produce high-quality research and ensure that harm is minimized in animals. The primary means of ensuring these goals are both met is the 3Rs framework of replacement, reduction, and refinement. However, some approaches to the 3Rs may result in a 'check box mentality' in which IACUC members, researchers, administrators, and caretakers check off a list of tasks to evaluate a protocol. We provide reasons for thinking that the 3Rs approach could be enhanced with more explicit discussion of the ethical assumptions used to arrive at an approved research protocol during IACUC review. Here we suggest that the notion of moral considerability, and all of the related issues it gives rise to, should be incorporated into IACUC discussions of 3Rs deliberations during protocol review to ensure that animal wellbeing is enhanced within the constraints of scientific investigation. PMID:25836970

  2. [Identification of the 1RS-7DS.7DL wheat-rye small segment translocation lines].

    PubMed

    Jun, Li; Xinguo, Zhu; Hongshen, Wan; Qin, Wang; Zongxiang, Tang; Shulan, Fu; Zujun, Yang; Manyu, Yang; Wuyun, Yang

    2015-06-01

    Rye (Secale cereale L., RR) is a valuable genetic resource for the improvement of common wheat (Triticum aestivum L., AABBDD). Transferring alien rye genes into wheat by distant hybridization and automatic chromosome doubling is an important and efficient method to boost agronomic traits, disease resistance and widening the gene pool in wheat. In this study, an octoploid triticale CD-13 (AABBDDRR) was obtained via automatic chromosome doubling by crossing landrace Penganbaimaizi (T. aestivum L., AABBDD) and rye "Qinling rye" (S. cereale cv. Qinling, RR). GISH and FISH analyses indicated that CD-13 contained a 1RS-7DS.7DL wheat-rye small segment translocation chromosome. In order to transfer the 1RS-7DS small segment translocation into hexaploid wheat, 58 lines of the F5 inbred population from the cross CD-13 x Chuanmai 42 were screened for rye chromosome segments by GISH and FISH analyses. The results showed that 13 lines contained the 1RS-7DS.7DL small segment translocation chromosome by reciprocal translocation between 1RS and 7DS. These translocation lines carrying 1RS small rye alien segment were tested for the translocation breakpoints and the presence of a storage protein locus Sec-1. The Sec-1 locus was absent in the line 811, a stable 1RS-7DS.7DL small segment translocation line. The translocation breakpoint of 1RS-7DS.7DL of this line was located in the interval of IB267-IAG95 around the telomere of 1RS chromosome. Thousand-kernel weight of the line 811 was much higher than the parent CD-13, but not significantly different from Chuanmai 42. This indicated that 1RS-7DS.7DL small segment translocation had no negative effect on thousand-kernel weight in the genetic background of Chuanmai 42. The line with 1RS-7DS.7DL translocation chromosomes can be used as a new genetic material for further studies of valuable genes and their genetic effect on 1RS small segment. PMID:26351056

  3. ADIPOQ polymorphism rs182052 is associated with clear cell renal cell carcinoma

    PubMed Central

    Zhang, Guiming; Gu, Chengyuan; Zhu, Yao; Luo, Lei; Dong, Dahai; Wan, Fangning; Zhang, Hailiang; Shi, Guohai; Sun, Lijiang; Ye, Dingwei

    2015-01-01

    Recent studies have indicated that low circulating adiponectin concentrations are associated with a higher risk of several cancers, including renal cell carcinoma. In this casecontrol study, we examined the frequency of single nucleotide polymorphisms (rs182052G>A, rs266729C>G, and rs3774262G>A) in the adiponectin gene (ADIPOQ) in 1004 patients with clear cell renal cell carcinoma (ccRCC) compared with a group of healthy subjects (n=1108). Fasting serum adiponectin concentrations were also examined. Logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (95% CI). The association of serum adiponectin concentration with genetic variants was calculated using a multivariate linear regression model. A significantly higher ccRCC risk was associated with the rs182052 variant A allele (adjusted OR, 1.36 and 95% CI, 1.071.74 for AA vs GG, P=0.013; adjusted OR, 1.27 and 95% CI, 1.041.56 for AA vs GG+AG, P=0.019), and this positive association was more evident in overweight subjects. Fasting serum adiponectin was lower in subjects carrying A alleles of rs182052 in both ccRCC patients (?=?0.399, P=0.018) and healthy controls (?=?0.371, P=0.024). These results suggest that ADIPOQ rs182052 is significantly associated with ccRCC risk. In this casecontrol study, we examined the frequency of single nucleotide polymorphisms (rs182052G>A, rs266729C>G, and rs3774262G>A) in the adiponectin gene (ADIPOQ) in 1004 patients with clear cell RCC (ccRCC) compared with a group of healthy subjects (n=1108). Fasting serum adiponectin concentrations were also examined. Fasting serum adiponectin was lower in subjects carrying minor alleles of rs182052 in both ccRCC patients (?=?0.399, P=0.018) and healthy controls (?=?0.371, P=0.024). These results suggest that ADIPOQ rs182052 is significantly associated with ccRCC risk. PMID:25827778

  4. Catch a Star!

    NASA Astrophysics Data System (ADS)

    2006-11-01

    ESO and the European Association for Astronomy Education are launching today the 2007 edition of 'Catch a Star!', their international astronomy competition for school students. Now in its fifth year, the competition offers students the chance to win a once-in-a-lifetime trip to ESO's flagship observatory in Chile, as well as many other prizes. Students are invited to 'become astronomers' and embark on a journey to explore the Universe. ESO PR Photo 42/06 The competition includes separate categories - 'Catch a Star Researchers' and 'Catch a Star Adventurers' - to ensure that every student, whatever their level, has the chance to enter and win exciting prizes. For the artistically minded, 'Catch a Star!' also includes an artwork competition, 'Catch a Star Artists'. "'Catch a Star!' offers a unique opportunity for students to learn more about astronomy and about the methods scientists use to discover new things about the Universe", said Douglas Pierce-Price, Education Officer at ESO. In teams, students choose an astronomical topic to study and produce an in-depth report. An important part of the project for 'Catch a Star Researchers' is to think about how ESO's telescopes or a telescope of the future can contribute to their investigations of the subject. As well as the top prize - a trip to one of ESO's observatory sites in Chile - visits to observatories in Germany, Austria and Spain, and many other prizes are also available to be won. 'Catch a Star Researchers' winners will be chosen by an international jury, and 'Catch a Star Adventurers' will be awarded further prizes by lottery. Entries for 'Catch a Star Artists' will be displayed on the web and winners chosen with the help of a public online vote. The first editions of 'Catch a Star!' have attracted several hundred entries from more than 25 countries worldwide. Previous winning entries have included "Star clusters and the structure of the Milky Way" (Budapest, Hungary), "Vega" (Acqui Terme, Italy) and "Venus transit" (Lleida, Spain). Some previous winning entries are visible on the Catch a Star! Web site. Detailed entry information can be found on ESO's website, at http://www.eso.org/catchastar/ The deadline for submitting an entry for the 2007 competition is Friday 2 March 2007, 17:00 Central European Time.

  5. Association between MC4R rs17782313 Polymorphism and Overeating Behaviours

    PubMed Central

    Yilmaz, Zeynep; Davis, Caroline; Loxton, Natalie J.; Kaplan, Allan S.; Levitan, Robert D.; Carter, Jacqueline C.; Kennedy, James L.

    2014-01-01

    Background/Objectives Melanocortins play a crucial role in appetite and weight regulation. Although the melanocortin 4 receptor (MC4R) gene has been repeatedly linked to obesity and antipsychotic-induced weight gain, the mechanism behind how it leads to this effect in still undetermined. The goal of this study was to conduct an in-depth and sophisticated analysis of MC4R polymorphisms, body mass index (BMI), eating behaviour, and depressed mood. Subjects/Methods We genotyped 328 individuals of European ancestry on the following MC4R markers based on the relevant literature on obesity and antipsychotic-induced weight gain: rs571312, rs17782313, rs489693, rs11872992, and rs8087522. Height and weight were measured, and information on depressed mood and overeating behaviours was obtained during the in-person assessment. Results BMI was associated with rs17782313 C allele; however this finding did not survive correction for multiple testing (p=0.018). Although rs17782313 was significantly associated with depressed mood and overeating behaviours, tests of indirect effects indicated that emotional eating and food cravings, rather than depressed mood, uniquely accounted for the effect of this marker and BMI (n=152). Conclusions To our knowledge, this is the first study to investigate the link between MC4R rs17782313, mood and overeating behaviour, as well as to demonstrate possible mechanisms behind MC4R’s influence on body weight. If replicated in a larger sample, these results may have important clinical implications, including potential for the use of MC4R agonists in the treatment of obesity and disordered eating. PMID:24827639

  6. A simplified algorithm for correcting both errors and erasures of R-S codes

    NASA Technical Reports Server (NTRS)

    Reed, I. S.; Truong, T. K.

    1978-01-01

    Using the finite field transform and continued fractions, a simplified algorithm for decoding Reed-Solomon (R-S) codes is developed to correct erasures caused by other codes as well as errors over the finite field GF (q(m), where q is a prime and m is an integer. Such an R-S decoder can be faster and simpler than a decoder that uses more conventional methods.

  7. A suite of RS/1 procedures for chemical laboratory statistical quality control and Shewhart control charting

    SciTech Connect

    Shanahan, K.L.

    1990-09-01

    A suite of RS/1 procedures for Shewhart control charting in chemical laboratories is described. The suite uses the RS series product QCA (Quality Control Analysis) for chart construction and analysis. The suite prompts users for data in a user friendly fashion and adds the data to or creates the control charts. All activities are time stamped. Facilities for generating monthly or contiguous time segment summary charts are included. The suite is currently in use at Westinghouse Savannah River Company.

  8. DNA methyltransferase 3a rs1550117 genetic polymorphism predicts poor survival in gastric cancer patients

    PubMed Central

    Wang, Chuan; Jia, Zhifang; Ma, Hongxi; Cao, Donghui; Wu, Xing; Wen, Simin; You, Lili; Cao, Xueyuan; Jiang, Jing

    2015-01-01

    DNA methyltransferase 3a (DNMT3a) have been suggested to play a crucial role in human cancer prognosis. Single nucleotide polymorphisms (SNPs) in DNMT3a genes may have an impact on the prognosis of cancers. This study aimed to investigate the association between SNPs of DNMT3a gene and prognosis of gastric cancer (GC). Two sites of DNMT3a SNPs, rs1550117 and rs13420827 were selected and genotyped using TaqMan assay in 447 GC patients who received gastrectomy. Effects of genotypes on clinical outcomes of GC were calculated by Kaplan-Meier survival analysis and Cox regression model. We found that the AG or AA genotype of rs1550117 was associated with significantly poorer survival and increased death risk of GC compared with GG genotype (dominant model: HR=1.35, 95% CI=1.01-1.80, P=0.043). Further multivariate Cox regression analysis revealed that in addition to the known factors including male, larger tumor sizes and high clinical stage, rs1550117 variant was an independently predictive factor for survival in GC patients. No significant association was found between rs13420827 genetic variants and GC prognosis. Our findings first demonstrated that DNMT3a rs1550117 polymorphism may be a potential biomarker in predicting overall survival of GC patients. PMID:26823816

  9. BDNF rs6265 methylation and genotype interact on risk for schizophrenia.

    PubMed

    Ursini, Gianluca; Cavalleri, Tommaso; Fazio, Leonardo; Angrisano, Tiziana; Iacovelli, Luisa; Porcelli, Annamaria; Maddalena, Giancarlo; Punzi, Giovanna; Mancini, Marina; Gelao, Barbara; Romano, Raffaella; Masellis, Rita; Calabrese, Francesca; Rampino, Antonio; Taurisano, Paolo; Giorgio, Annabella Di; Keller, Simona; Tarantini, Letizia; Sinibaldi, Lorenzo; Quarto, Tiziana; Popolizio, Teresa; Caforio, Grazia; Blasi, Giuseppe; Riva, Marco A; De Blasi, Antonio; Chiariotti, Lorenzo; Bollati, Valentina; Bertolino, Alessandro

    2016-01-01

    Epigenetic mechanisms can mediate gene-environment interactions relevant for complex disorders. The BDNF gene is crucial for development and brain plasticity, is sensitive to environmental stressors, such as hypoxia, and harbors the functional SNP rs6265 (Val(66)Met), which creates or abolishes a CpG dinucleotide for DNA methylation. We found that methylation at the BDNF rs6265 Val allele in peripheral blood of healthy subjects is associated with hypoxia-related early life events (hOCs) and intermediate phenotypes for schizophrenia in a distinctive manner, depending on rs6265 genotype: in ValVal individuals increased methylation is associated with exposure to hOCs and impaired working memory (WM) accuracy, while the opposite is true for ValMet subjects. Also, rs6265 methylation and hOCs interact in modulating WM-related prefrontal activity, another intermediate phenotype for schizophrenia, with an analogous opposite direction in the 2 genotypes. Consistently, rs6265 methylation has a different association with schizophrenia risk in ValVals and ValMets. The relationships of methylation with BDNF levels and of genotype with BHLHB2 binding likely contribute to these opposite effects of methylation. We conclude that BDNF rs6265 methylation interacts with genotype to bridge early environmental exposures to adult phenotypes, relevant for schizophrenia. The study of epigenetic changes in regions containing genetic variation relevant for human diseases may have beneficial implications for the understanding of how genes are actually translated into phenotypes. PMID:26889735

  10. Association between JAK2 rs4495487 Polymorphism and Risk of Budd-Chiari Syndrome in China

    PubMed Central

    Zhang, Peijin; Zhang, Yanyan; Zhang, Jing; Wang, Hui; Ma, He; Wang, Wei; Gao, Xiuyin; Xu, Hao; Lu, Zhaojun

    2015-01-01

    Myeloproliferative neoplasms (MPNs) are the leading cause of Budd-Chiari syndrome (BCS), and the C allele of JAK2 rs4495487 was reported to be an additional candidate locus that contributed to MPNs. In the present study, we examined the role of JAK2 rs4495487 in the etiology and clinical presentation of Chinese BCS patients. 300 primary BCS patients and 311 healthy controls were enrolled to evaluate the association between JAK2 rs4495487 polymorphism and risk of BCS. All subjects were detected for JAK2 rs4495487 by real-time PCR. Results. The JAK2 rs4495487 polymorphism was associated with JAK2 V617F-positive BCS patients compared with controls (P < 0.01). The CC genotype increased the risk of BCS in patients with JAK2 V617F mutation compared with individuals presenting TT genotype (OR = 13.60, 95% CI = 2.04–90.79) and non-CC genotype (OR = 12.00, 95% CI = 2.07–69.52). We also observed a significantly elevated risk of combined-type BCS associated with CC genotype in the recessive model (OR = 4.44, 95% CI = 1.31–15.12). This study provides statistical evidence that the JAK2 rs4495487 polymorphism is susceptibility factor JAK2 V617F positive BCS and combined BCS in China. Further larger studies are required to confirm these findings. PMID:26557140

  11. Association study of BUD13-ZNF259 gene rs964184 polymorphism and hemorrhagic stroke risk

    PubMed Central

    Zhou, Shengjun; Zhao, Jikuang; Wang, Zhepei; Li, Keqin; Nie, Sheng; Gao, Feng; Sun, Jie; Gao, Xiang; Huang, Yi

    2015-01-01

    We aimed to evaluate the association of rs964184 of BUD13-ZNF259 gene with the risk of hemorrhagic stroke (HS). A total of 138 HS cases and 587 controls were recruited for the association of rs964184 of BUD13-ZNF259 gene with the risk of HS. Tm shift PCR was used for genotyping. We were unable to find the association of rs964184 of BUD13-ZNF259 gene with the risk of HS (P>0.05). Significant difference was found in the TG level among the three genotypes (CC: 1.51±1.02; CG: 1.68±1.10; GG: 1.90±1.11, P=0.036). The TG level showed strong correlation with rs964184 genotypes (P=0.010, correlation=0.101). Significantly higher TC, HDL-C, and LDL-C levels were observed in the case group. And no difference was found in the TG, ApoA-I, ApoB. Our case-control study supported the significant association between rs964184 genotype and the blood TG concentration, although we were unable to find association between BUD13-ZNF259 rs964184 and the risk of HS in Han Chinese. PMID:26885234

  12. Positive Association between GCKR rs780093 Polymorphism and Coronary Heart Disease in the Aged Han Chinese

    PubMed Central

    Lian, Jiangfang; Guo, Jian; Chen, Zhikui; Jiang, Qingjun; Ye, Huadan; Huang, Xiaoyan; Yang, Xi; Ba, Yanna; Zhou, Jianqing

    2013-01-01

    Objective. Previous studies have confirmed that GCKR rs780093 polymorphism is associated with triglyceride (TG), a known risk factor of coronary heart disease (CHD). The goal of our study is to explore the association of GCKR rs780093 polymorphism with CHD in Han Chinese population. Methods and Results. A total of 568 CHD cases and 494 non-CHD controls were enrolled in the current case-control study. Genotyping was done using melting temperature shift (Tm-shift) approach. Our results also showed that GCKR rs780093 polymorphism was significantly associated with TG level (P = 0.0016). Although there was no significant association between cases and controls (P > 0.05), a breakdown analysis by age yielded a significant association of GCKR rs780093 polymorphism with CHD in individuals aged 65 and older (genotype: χ2 = 6.86; df = 2; P = 0.03; allele: χ2 = 4.11; df = 1; P = 0.04). Conclusion. Our findings confirmed the contribution of GCKR rs780093 polymorphism to TG metabolism and demonstrated GCKR rs780093 as a risk factor of CHD in individuals aged 65 and older. PMID:24385677

  13. Influence of the hTERT rs2736100 polymorphism on telomere length in gastric cancer

    PubMed Central

    Choi, Byung Joon; Yoon, Jung Hwan; Kim, Olga; Choi, Won Suk; Nam, Suk Woo; Lee, Jung Young; Park, Won Sang

    2015-01-01

    AIM: To investigate the functional consequences of rs2736100 polymorphism in telomere length and examine its link to gastric cancer risk. METHODS: Telomere length and human telomerase reverse transcriptase (hTERT) mRNA expression were measured in 35 gastric cancer tissues and 5 cell lines and correlated to rs2736100 polymorphism. The relationship between rs2736100 polymorphism and the risk of gastric cancer were examined in 243 gastric cancer patients and 246 healthy individuals. RESULTS: The rs2736100 A allele carrier is closely associated with reduced hTERT mRNA expression and shortened telomere length in gastric cancer tissue and cell lines. When gastric cancers were stratified by histological subtype, telomere length and hTERT mRNA levels were significantly increased in those with the C/C genotype in intestinal-type gastric cancer, but not in diffuse-type gastric cancer. Interestingly, there was no significant difference in the genotype and allele frequencies of the rs2736100 polymorphism between the patients with gastric cancer and healthy controls. CONCLUSION: The rs2736100 polymorphism of the hTERT gene is involved in the regulation of hTERT expression and telomere length, but not in the risk of gastric cancer. PMID:26309358

  14. The Use of Systematic Reviews and Reporting Guidelines to Advance the Implementation of the 3Rs

    PubMed Central

    Avey, Marc T; Fenwick, Nicole; Griffin, Gilly

    2015-01-01

    In 1959, Russell and Burch published The Principles of Humane Experimental Technique, which included concrete advice on factors that they considered would govern progress in the implementation of these principles (enunciated as the 3Rs [Replacement, Reduction, and Refinement in animal-based studies]). One challenge to the implementation of the 3Rs was identified as information retrieval. Here, we further explore this challenge—the need for ‘research on research’—and the role that systematic reviews and reporting guidelines can play in implementation of the 3Rs. First, we examine the 2-fold nature of the challenge of information retrieval: 1) the identification of relevant publications spread throughout a large population of nonrelevant publications and 2) the incomplete reporting of relevant details within those publications. Second, we evaluate how systematic reviews and reporting guidelines can be used generally to address this challenge. Third, we assess the explicit reporting of the 3Rs in a cohort of preclinical animal systematic reviews. Our results show that Reduction methods are the most commonly reported by authors of systematic reviews but that, in general, reporting on how findings relate to the 3Rs is limited at best. Although systematic reviews are excellent tools for resolving the challenge of information retrieval, their utility for making progress in implementation of the 3Rs may be limited unless authors improve their reporting of these principles. PMID:25836961

  15. Performance of CO-OFDM system with RS-Turbo concatenated code

    NASA Astrophysics Data System (ADS)

    Tong, Zheng-rong; Hu, Gui-bin; Cao, Ye; Zhang, Wei-hua

    2015-11-01

    In this paper, the RS-Turbo concatenated code is applied to coherent optical orthogonal frequency division multiplexing (CO-OFDM) system. RS(186,166,8) and Turbo code with code rate of 1/2 are employed for RS-Turbo concatenated code. Two decoding algorithms, which are Max-Log-MAP algorithm and Log-MAP algorithm, are adopted for Turbo decoding, and the iteration Berlekamp-Massey (BM) algorithm is adopted for RS decoding. The simulation results show that the bit error rate ( BER) performance of CO-OFDM system with RS-Turbo concatenated code is significantly improved at high optical signal to noise ratio ( OSNR), and the iteration number is reduced compared with that of the Turbo coded system. Furthermore, when the Max-Log-MAP algorithm is adopted for Turbo decoding, the transmission distance of CO-OFDM system with RS-Turbo concatenated code can reach about 400 km without error, while that of the Turbo coded system can only reach about 240 km when BER is lower than 10-4 order of magnitude.

  16. Association Between MIF-AS rs755622 and Nephrolithiasis Risk in a Chinese Population

    PubMed Central

    Ma, Gaoxiang; Yuan, Qinbo; Wang, Qiangdong; Du, Mulong; Chu, Haiyan; Dong, Zhenjia; Xiao, Xu; Wang, Meilin; Qin, Chao; Yin, Changjun; Zhang, Zhengdong; Zhang, Wei

    2016-01-01

    Background Single-nucleotide polymorphisms (SNPs) located at lncRNA may affect the stability and splicing processes of mRNA formation, which result in the alteration of its interacting partners. The SNP rs755622 within exon of antisense lncRNA MIF- AS and promoter of MIF was implicated in renal disease risk. Material/Methods In this case-control study, we genotyped the SNP rs755622 in 230 patients diagnosed with nephrolithiasis and 250 controls in a Chinese population. Results We found that the rs755622 CG and CC genotypes had a significantly increased nephrolithiasis risk (adjusted OR=1.52, 95% CI=1.03–2.25; OR=2.63, 95% CI=1.21–5.72, P=0.015), compared with GG genotype in the additive model. The rs755622 C carriers (GC/CC) had an adjusted OR (95% CI) of 1.65 (1.14–2.39, P=0.016), compared with the GG genotype in the dominant model. This hazardous effect was more pronounced in subgroup age >46, BMI >24, hypertension, ever smoking, and ever drinking subjects. Moreover, we found that rs755622 could modulate the function of MIF-AS by influencing its folding. Conclusions These results indicate that the MIF-AS rs755622 polymorphism may have a crucial role in the development of nephrolithiasis. PMID:26895959

  17. Making star teams out of star players.

    PubMed

    Mankins, Michael; Bird, Alan; Root, James

    2013-01-01

    Top talent is an invaluable asset: In highly specialized or creative work, for instance, "A" players are likely to be six times as productive as "B" players. So when your company has a crucial strategic project, why not multiply all that firepower and have a team of your best performers tackle it? Yet many companies hesitate to do this, believing that all-star teams don't work: Big egos will get in the way. The stars won't be able to work with one another. They'll drive the team Leader crazy. Mankins, Bird, and Root of Bain & Company believe it's time to set aside that thinking. They have seen all-star teams do extraordinary work. But there is a right way and a wrong way to organize them. Before you can even begin to assemble such a team, you need to have the right talent management practices, so you hire and develop the best people and know what they're capable of. You have to give the team appropriate incentives and leaders and support staffers who are stars in their own right. And projects that are ill-defined or small scale are not for all-star teams. Use them only for critical missions, and make sure their objectives are clear. Even with the right setup, things can still go wrong. The wise executive will take steps to manage egos, prune non-team-players, and prevent average coworkers from feeling completely undervalued. She will also invest a lot of time in choosing the right team Leader and will ask members for lots of feedback to monitor how that leader is doing. PMID:23390743

  18. Two tagSNPs rs352493 and rs3760908 within SIRT6 Gene Are Associated with the Severity of Coronary Artery Disease in a Chinese Han Population

    PubMed Central

    Tang, Sai-sai; Xu, Shun; Cheng, Jie; Cai, Meng-yun; Chen, Lin; Liang, Li-li; Yang, Xi-li; Chen, Can; Liu, Xin-guang; Xiong, Xing-dong

    2016-01-01

    SIRT6 has been demonstrated to exert protective effects on endothelial cells and is closely associated with lipid metabolism, glucose metabolism, and obesity, indicating an important role in the pathogenesis and progression of coronary artery disease (CAD). Nonetheless, the biological significance of SIRT6 variants on CAD is far to be elucidated. Here we aimed to investigate the influence of SIRT6 polymorphisms on individual susceptibility and severity of CAD. Multivariate logistic regression analysis exhibited no significant association between these five polymorphisms and CAD risk in the genotype and allele frequencies. However, we found that the rs352493 polymorphism in SIRT6 exhibited a significant effect on the severity of CAD; C allele (χ2 = 7.793, adjusted P = 0.013) and the combined CC/CT genotypes (χ2 = 5.609, adjusted P = 0.031) presented the greater CAD severity. In addition, A allele (χ2 = 5.208, adjusted P = 0.046) and AA (χ2 = 4.842, adjusted P = 0.054) of rs3760908 were also associated with greater CAD severity in Chinese subjects. Our data provided the first evidence that SIRT6 tagSNPs rs352493 and rs3760908 play significant roles in the severity of CAD in Chinese Han subjects, which might be useful predictors of the severity of CAD. PMID:27118880

  19. Impact of IL28B gene polymorphisms rs8099917 and rs12980275 on response to pegylated interferon-α/ribavirin therapy in chronic hepatitis C genotype 4 patients

    PubMed Central

    Khattab, Mahmoud A; Abdelghany, Hend M; Ramzy, Maggie M; Khairy, Rasha M

    2016-01-01

    Abstract Host genetic factors may predict the outcome and treatment response in hepatitis C virus (HCV) infection. One of these factors is the single nucleotide polymorphisms of the interleukin 28B (IL28B) gene. We sought to evaluate the outcome of pegylated interferon and ribavirin therapy in association with IL-28B rs8099917 and rs12980275 in patients infected with HCV genotype 4. A total of 180 patients with chronic hepatitis C were selected from Egyptians who have received combined therapy with pegylated interferon and ribavirin for 6 months and their response was evaluated after follow-up at 0, 6, 12, 24 and 48 weeks from the beginning of the therapy. Blood samples were collected from responders and non-responders. Genomic DNA was extracted from whole blood and genotyping was carried out by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). Our results showed that TT genotype of rs8099917 was associated with higher sustained viral response (SVR) rates and G allele represented a risk factor for failure of response (OR = 3.7, CI = 1.8:7.64) while rs12980275 was not significantly associated with SVR in genotype 4 Egyptian patients. The determination of IL-28B SNPs may be useful in enhancing correct prediction of SVR achievement in treating this group of genotype 4 patients.

  20. Measuring stars with Gaia

    NASA Astrophysics Data System (ADS)

    Thévenin, F.

    2013-12-01

    Beyond the extraordinary three dimensional map that Gaia will create for a billion of stars, it will reveal the origin and history of the Milky Way as the major goal. This does not weakness the fantastic impact of Gaia on the stellar physic. It will put constraints on the modeling of stars to an extreme that consequently new input physics will be mandatory to understand a Gaia HR diagram. Stars are formed in populations and evolve as collection of objects revealing important clues on how they formed, what kind of mass function is active during the star formation, how frequent is the star formation, all of this is imprinted in the intrinsic properties of stars that large surveys combined together like Gaia, Kepler, PLATO will revealed. The characterization of stars hosting planets is also a goal of such combination of large surveys and in particular of the measure of distances in the Galaxy. The launch of Gaia is for November of 2013 and the output catalogue is expected for 2020. Then will start the beginning of a new Astrophysics touching so many topics that a new age of astrophysics is then foreseen.

  1. Pseudosynchronization of Heartbeat Stars

    NASA Astrophysics Data System (ADS)

    Zimmerman, Mara; Thompson, Susan E.; Hambleton, Kelly; Fuller, Jim; Shporer, Avi; Isaacson, Howard T.; Howard, Andrew; Kurtz, Donald

    2016-01-01

    A type of eccentric binary star that undergoes extreme dynamic tidal forces, known as Heartbeat stars, were discovered by the Kepler Mission. As the two stars pass through periastron, the tidal distortion causes unique brightness variations. Short period, eccentric binary stars, like these, are theorized to pseudosynchronize, or reach a rotational frequency that matches the weighted average orbital angular velocity of the system. This pseudosynchronous rate, as predicted by Hut (1981), depends on the binary's orbital period and eccentricity. We tested whether sixteen heartbeat stars have pseudosynchronized. We measure the rotation rate from obvious spot signatures in the light curve. We measure the eccentricity by fitting the light curve using PHOEBE and are actively carrying out a radial velocity monitoring program with Keck/HIRES in order to improve these orbital parameters. Our initial results show that while most heartbeat stars appear to have pseudosynchronized we find stars with rotation frequencies both longer and shorter than this rate. We thank the SETI Institute REU program, the NSF, and the Kepler Guest Observer Program for making this work possible.

  2. Evidence for Low-dimensional Chaos in Semiregular Variable Stars

    NASA Astrophysics Data System (ADS)

    Buchler, J. Robert; Kollth, Zoltn; Cadmus, Robert R., Jr.

    2004-09-01

    We present an analysis of the photometric observations of the light curves of the five large-amplitude, irregularly pulsating stars R UMi, RS Cyg, V CVn, UX Dra, and SX Her. First, multiperiodicity is eliminated for these pulsations; i.e., they are not caused by the excitation of a small number of pulsation modes with constant amplitudes. Next, on the basis of energetics we also eliminate stochasticity as a cause, leaving low-dimensional chaos as the only alternative. We then use a global flow reconstruction technique in an attempt to extract quantitative information from the light curves and to uncover common physical features in this class of irregular variable stars that straddle the RV Tau to the Mira variables. Evidence is presented that the pulsational behavior of R UMi, RS Cyg, V CVn, and UX Dra takes place in a four-dimensional dynamical phase space, suggesting that two vibrational modes are involved in the pulsation. A linear stability analysis of the fixed points of the maps further indicates the existence of a two-mode resonance, similar to the one we had uncovered earlier in R Sct. The irregular pulsations are the result of a continual energy exchange between two strongly nonadiabatic modes, a lower frequency pulsation mode and an overtone that are in a close 2:1 resonance. The evidence is particularly convincing for R UMi, RS Cyg, and V CVn, but much weaker for UX Dra. In contrast, the pulsations of SX Her appear to be more complex and may require a six-dimensional space.

  3. Infrared spectroscopy of stars

    NASA Technical Reports Server (NTRS)

    Merrill, K. M.; Ridgway, S. T.

    1979-01-01

    This paper reviews applications of IR techniques in stellar classification, studies of stellar photospheres, elemental and isotopic abundances, and the nature of remnant and ejected matter in near-circumstellar regions. Qualitative IR spectral classification of cool and hot stars is discussed, along with IR spectra of peculiar composite star systems and of obscured stars, and IR characteristics of stellar populations. The use of IR spectroscopy in theoretical modeling of stellar atmospheres is examined, IR indicators of stellar atmospheric composition are described, and contributions of IR spectroscopy to the study of stellar recycling of interstellar matter are summarized. The future of IR astronomy is also considered.

  4. Equivalence of star products

    NASA Astrophysics Data System (ADS)

    Bertelson, Mélanie; Cahen, Michel; Gutt, Simone

    1997-01-01

    We give an elementary proof of the fact that equivalence classes of smooth or differentiable star products on a symplectic manifold M are parametrized by sequences of elements in the second de Rham cohomology space of the manifold. The parametrization is given explicitly in terms of Fedosov's construction which yields a star product when one chooses a symplectic connection and a sequence of closed 2-forms on M. We also show how derivations of a given star product, modulo inner derivations, are parametrized by sequences of elements in the first de Rham cohomology space of M.

  5. Polychromatic Laser Guide Star

    NASA Astrophysics Data System (ADS)

    Foy, Renaud

    2001-05-01

    We briefly recall the aim and the principle of ELP-OA, the polychromatic laser guide star programme, which aims at mesuring the wavefront tilt from a laser guide star. We describe the results of the feasibility study of this concept, addressing in particular the budget link, the measurement of telescope vibrations, the accuracy of the tilt measurements and the the return flux from the mesosphere as measured from sky experiments. We conclude with the perspectives of the polychromatic laser guide star with respect to forthcoming developments of adaptive optics at large telescopes.

  6. Mariner 9 star photography.

    NASA Technical Reports Server (NTRS)

    Thorpe, T. E.

    1973-01-01

    Mariner 9 achieved successful photography of the stars, the purpose of the experiment being to measure camera parameters associated with point source photometry, and to examine the feasibility of using stars as invariant calibration sources and a reference for optical navigation. The Mariner 9 camera-B photography demonstrated photometric response consistency over a limited sample of data to better than 15%. Camera performance verified the ability to model vidicon response characteristics as well as demonstrated an imaging capability sufficient to permit the use of stars for photometric calibration.

  7. Strange nonchaotic stars.

    PubMed

    Lindner, John F; Kohar, Vivek; Kia, Behnam; Hippke, Michael; Learned, John G; Ditto, William L

    2015-02-01

    The unprecedented light curves of the Kepler space telescope document how the brightness of some stars pulsates at primary and secondary frequencies whose ratios are near the golden mean, the most irrational number. A nonlinear dynamical system driven by an irrational ratio of frequencies generically exhibits a strange but nonchaotic attractor. For Kepler's "golden" stars, we present evidence of the first observation of strange nonchaotic dynamics in nature outside the laboratory. This discovery could aid the classification and detailed modeling of variable stars. PMID:25699444

  8. On the conversion of neutron stars into quark stars

    NASA Astrophysics Data System (ADS)

    Pagliara, Giuseppe

    2014-03-01

    The possible existence of two families of compact stars, neutron stars and quark stars, naturally leads to a scenario in which a conversion process between the two stellar objects occurs with a consequent release of energy of the order of 1053 erg. We discuss recent hydrodynamical simulations of the burning process and neutrino diffusion simulations of cooling of a newly formed strange star. We also briefly discuss this scenario in connection with recent measurements of masses and radii of compact stars.

  9. Successful fabrication of a convex platform PMMA cell-counting slide using a high-precision perpendicular dual-spindle CNC machine tool

    NASA Astrophysics Data System (ADS)

    Chen, Shun-Tong; Chang, Chih-Hsien

    2013-12-01

    This study presents a novel approach to the fabrication of a biomedical-mold for producing convex platform PMMA (poly-methyl-meth-acrylate) slides for counting cells. These slides allow for the microscopic examination of urine sediment cells. Manufacturing of such slides incorporates three important procedures: (1) the development of a tabletop high-precision dual-spindle CNC (computerized numerical control) machine tool; (2) the formation of a boron-doped polycrystalline composite diamond (BD-PCD) wheel-tool on the machine tool developed in procedure (1); and (3) the cutting of a multi-groove-biomedical-mold array using the formed diamond wheel-tool in situ on the developed machine. The machine incorporates a hybrid working platform providing wheel-tool thinning using spark erosion to cut, polish, and deburr microgrooves on NAK80 steel directly. With consideration given for the electrical conductive properties of BD-PCD, the diamond wheel-tool is thinned to a thickness of 5 µm by rotary wire electrical discharge machining. The thinned wheel-tool can grind microgrooves 10 µm wide. An embedded design, which inserts a close fitting precision core into the biomedical-mold to create step-difference (concave inward) of 50 µm in height between the core and the mold, is also proposed and realized. The perpendicular dual-spindles and precision rotary stage are features that allow for biomedical-mold machining without the necessity of uploading and repositioning materials until all tasks are completed. A PMMA biomedical-slide with a plurality of juxtaposed counting chambers is formed and its usefulness verified.

  10. The BTB and CNC Homology 1 (BACH1) Target Genes Are Involved in the Oxidative Stress Response and in Control of the Cell Cycle*

    PubMed Central

    Warnatz, Hans-Jörg; Schmidt, Dominic; Manke, Thomas; Piccini, Ilaria; Sultan, Marc; Borodina, Tatiana; Balzereit, Daniela; Wruck, Wasco; Soldatov, Alexey; Vingron, Martin; Lehrach, Hans; Yaspo, Marie-Laure

    2011-01-01

    The regulation of gene expression in response to environmental signals and metabolic imbalances is a key step in maintaining cellular homeostasis. BTB and CNC homology 1 (BACH1) is a heme-binding transcription factor repressing the transcription from a subset of MAF recognition elements at low intracellular heme levels. Upon heme binding, BACH1 is released from the MAF recognition elements, resulting in increased expression of antioxidant response genes. To systematically address the gene regulatory networks involving BACH1, we combined chromatin immunoprecipitation sequencing analysis of BACH1 target genes in HEK 293 cells with knockdown of BACH1 using three independent types of small interfering RNAs followed by transcriptome profiling using microarrays. The 59 BACH1 target genes identified by chromatin immunoprecipitation sequencing were found highly enriched in genes showing expression changes after BACH1 knockdown, demonstrating the impact of BACH1 repression on transcription. In addition to known and new BACH1 targets involved in heme degradation (HMOX1, FTL, FTH1, ME1, and SLC48A1) and redox regulation (GCLC, GCLM, and SLC7A11), we also discovered BACH1 target genes affecting cell cycle and apoptosis pathways (ITPR2, CALM1, SQSTM1, TFE3, EWSR1, CDK6, BCL2L11, and MAFG) as well as subcellular transport processes (CLSTN1, PSAP, MAPT, and vault RNA). The newly identified impact of BACH1 on genes involved in neurodegenerative processes and proliferation provides an interesting basis for future dissection of BACH1-mediated gene repression in neurodegeneration and virus-induced cancerogenesis. PMID:21555518

  11. An intronic PICALM polymorphism, rs588076, is associated with allelic expression of a PICALM isoform

    PubMed Central

    2014-01-01

    Background Although genome wide studies have associated single nucleotide polymorphisms (SNP)s near PICALM with Alzheimer’s disease (AD), the mechanism underlying this association is unclear. PICALM is involved in clathrin-mediated endocytosis and modulates Aß clearance in vitro. Comparing allelic expression provides the means to detect cis-acting regulatory polymorphisms. Thus, we evaluated whether PICALM showed allele expression imbalance (AEI) and whether this imbalance was associated with the AD-associated polymorphism, rs3851179. Results We measured PICALM allelic expression in 42 human brain samples by using next-generation sequencing. Overall, PICALM demonstrated equal allelic expression with no detectable influence by rs3851179. A single sample demonstrated robust global PICALM allelic expression imbalance (AEI), i.e., each of the measured isoforms showed AEI. Moreover, the PICALM isoform lacking exons 18 and 19 (D18-19 PICALM) showed significant AEI in a subset of individuals. Sequencing these individuals and subsequent genotyping revealed that rs588076, located in PICALM intron 17, was robustly associated with this imbalance in D18-19 PICALM allelic expression (p = 9.54 x 10-5). This polymorphism has been associated previously with systolic blood pressure response to calcium channel blocking agents. To evaluate whether this polymorphism was associated with AD, we genotyped 3269 individuals and found that rs588076 was modestly associated with AD. However, when both the primary AD SNP rs3851179 was added to the logistic regression model, only rs3851179 was significantly associated with AD. Conclusions PICALM expression shows no evidence of AEI associated with rs3851179. Robust global AEI was detected in one sample, suggesting the existence of a rare SNP that strongly modulates PICALM expression. AEI was detected for the D18-19 PICALM isoform, and rs588076 was associated with this AEI pattern. Conditional on rs3851179, rs588076 was not associated with AD risk, suggesting that D18-19 PICALM is not critical in AD. In summary, this analysis of PICALM allelic expression provides novel insights into the genetics of PICALM expression and AD risk. PMID:25169757

  12. An X-ray survey for pre-main-sequence stars in the Taurus-Auriga and Perseus molecular cloud complexes

    NASA Technical Reports Server (NTRS)

    Feigelson, E. D.; Jackson, J. M.; Mathieu, R. D.; Myers, P. C.; Walter, F. M.

    1987-01-01

    Seventy-five fields from the Einstein X-Ray Observatory IPC detector between 3h and 5h right ascension and 15 deg and 35 deg declination are examined to search for X-ray-emitting low-mass pre-main-sequence (PMS) stars. Six such stars were previously found; they appear to be similar to T Tauri stars but without dense circumstellar envelopes or winds. Finding charts are presented for 59 X-ray sources that may be PMS stars. While some are likely to be spurious X-ray sources, chance coincidences with unrelated stars, or non-PMS stellar sources such as RS CVn type binaries, approximately half are probably X-ray-selected PMS stars.

  13. Mass loss of massive stars

    NASA Astrophysics Data System (ADS)

    Martins, F.

    2015-12-01

    In this contribution we review the properties of the winds of massive stars. We focus on OB stars, red supergiants, Luminous Blue Variables (LBVs) and Wolf-Rayet stars. For each type of star, we summarize the main wind properties and we give a brief description of the physical mechanism(s) responsible for mass loss.

  14. Variation of tidal dissipation in the convective envelope of low-mass stars along their evolution

    NASA Astrophysics Data System (ADS)

    Mathis, S.

    2015-08-01

    Context. Since 1995, more than 1500 exoplanets have been discovered around a wide variety of host stars (from M- to A-type stars). Tidal dissipation in stellar convective envelopes is an important factor that shapes the orbital architecture of short-period systems. Aims: Our objective is to understand and evaluate how tidal dissipation in the convective envelope of low-mass stars (from M to F types) depends on their mass, evolutionary stage, and rotation. Methods: Using a simplified two-layer assumption, we analytically compute the frequency-averaged tidal dissipation in the convective envelope. This dissipation is due to the conversion into heat of the kinetic energy of tidal non-wavelike/equilibrium flow and inertial waves because of the viscous friction applied by turbulent convection. Using grids of stellar models allows us to study the variation of the dissipation as a function of stellar mass and age on the pre-main sequence and on the main sequence for stars with masses ranging from 0.4 to 1.4 M⊙. Results: During their pre-main sequence, all low-mass stars have an increase in the frequency-averaged tidal dissipation for a fixed angular velocity in their convective envelope until they reach a critical aspect and mass ratios (respectively α = Rc/Rs and β = Mc/Ms, where Rs,Ms,Rc, and Mc are the star's radius and mass and its radiative core's radius and mass). Next, the dissipation evolves on the main sequence to an asymptotic value that is highest for 0.6 M⊙ K-type stars and that then decreases by several orders of magnitude with increasing stellar mass. Finally, the rotational evolution of low-mass stars strengthens the importance of tidal dissipation during the pre-main sequence for star-planet and multiple star systems. Conclusions: As shown by observations, tidal dissipation in stars' convection zones varies over several orders of magnitude as a function of stellar mass, age, and rotation. We demonstrate that i) it reaches a maximum value on the pre-main sequence for all stellar masses and ii) on the main sequence and at fixed angular velocity, it is at a maximum for 0.6 M⊙ K-type stars and decreases with increasing mass. Appendix A is available in electronic form at http://www.aanda.org

  15. Variable star data online

    NASA Astrophysics Data System (ADS)

    Pickard, Roger; Wilson, Andy; Poyner, Gary

    2012-06-01

    Roger Pickard, Andy Wilson and Gary Poyner describe the online database of the British Astronomical Association Variable Star Section, a treasure trove of observations stretching back nearly 125 years.

  16. Cooling of neutron stars

    NASA Technical Reports Server (NTRS)

    Pethick, C. J.

    1992-01-01

    It is at present impossible to predict the interior constitution of neutron stars based on theory and results from laboratory studies. It has been proposed that it is possible to obtain information on neutron star interiors by studying thermal radiation from their surfaces, because neutrino emission rates, and hence the temperature of the central part of a neutron star, depend on the properties of dense matter. The theory predicts that neutron stars cool relatively slowly if their cores are made up of nucleons, and cool faster if the matter is in an exotic state, such as a pion condensate, a kaon condensate, or quark matter. This view has recently been questioned by the discovery of a number of other processes that could lead to copious neutrino emission and rapid cooling.

  17. Guide star probabilities

    NASA Technical Reports Server (NTRS)

    Soneira, R. M.; Bahcall, J. N.

    1981-01-01

    Probabilities are calculated for acquiring suitable guide stars (GS) with the fine guidance system (FGS) of the space telescope. A number of the considerations and techniques described are also relevant for other space astronomy missions. The constraints of the FGS are reviewed. The available data on bright star densities are summarized and a previous error in the literature is corrected. Separate analytic and Monte Carlo calculations of the probabilities are described. A simulation of space telescope pointing is carried out using the Weistrop north galactic pole catalog of bright stars. Sufficient information is presented so that the probabilities of acquisition can be estimated as a function of position in the sky. The probability of acquiring suitable guide stars is greatly increased if the FGS can allow an appreciable difference between the (bright) primary GS limiting magnitude and the (fainter) secondary GS limiting magnitude.

  18. Cosmology with hypervelocity stars

    SciTech Connect

    Loeb, Abraham

    2011-04-01

    In the standard cosmological model, the merger remnant of the Milky Way and Andromeda (Milkomeda) will be the only galaxy remaining within our event horizon once the Universe has aged by another factor of ten, ∼ 10{sup 11} years after the Big Bang. After that time, the only extragalactic sources of light in the observable cosmic volume will be hypervelocity stars being ejected continuously from Milkomeda. Spectroscopic detection of the velocity-distance relation or the evolution in the Doppler shifts of these stars will allow a precise measurement of the vacuum mass density as well as the local matter distribution. Already in the near future, the next generation of large telescopes will allow photometric detection of individual stars out to the edge of the Local Group, and may target the ∼ 10{sup 5±1} hypervelocity stars that originated in it as cosmological tracers.

  19. Molecules in star formation.

    NASA Astrophysics Data System (ADS)

    Shu, F. H.

    The author reviews current ideas and models in the problem of star formation from molecular cloud cores that are relatively isolated from the influences of other forming stars. He discusses the time scales, flow dynamics, and density and temperature structures applicable to each of the four stages of the entire process: (1) formation of a magnetized cloud core by ambipolar diffusion and evolution to a pivotal state of gravomagneto catastrophe; (2) self-similar collapse of the pivotal configuration and the formation of protostars, disks, and pseudo-disks; (3) onset of a magnetocentrifugally driven, lightly ionized wind from the interaction of an accretion disk and the magnetosphere of the central star, and the driving of bipolar molecular outflows; (4) evolution of pre-main-sequence stars surrounded by dusty accretion disks. For each of these stages and processes, he considers the characteristics of the molecular diagnostics needed to investigate the crucial aspects of the observational problem.

  20. Planets Around Neutron Stars

    NASA Technical Reports Server (NTRS)

    Wolszczan, Alexander; Kulkarni, Shrinivas R; Anderson, Stuart B.

    2003-01-01

    The objective of this proposal was to continue investigations of neutron star planetary systems in an effort to describe and understand their origin, orbital dynamics, basic physical properties and their relationship to planets around normal stars. This research represents an important element of the process of constraining the physics of planet formation around various types of stars. The research goals of this project included long-term timing measurements of the planets pulsar, PSR B1257+12, to search for more planets around it and to study the dynamics of the whole system, and sensitive searches for millisecond pulsars to detect further examples of old, rapidly spinning neutron stars with planetary systems. The instrumentation used in our project included the 305-m Arecibo antenna with the Penn State Pulsar Machine (PSPM), the 100-m Green Bank Telescope with the Berkeley- Caltech Pulsar Machine (BCPM), and the 100-m Effelsberg and 64-m Parkes telescopes equipped with the observatory supplied backend hardware.