WorldWideScience

Sample records for type ia sn2006x

  1. Type Ia Supernova Cosmology

    Science.gov (United States)

    Leibundgut, B.; Sullivan, M.

    2018-03-01

    The primary agent for Type Ia supernova cosmology is the uniformity of their appearance. We present the current status, achievements and uncertainties. The Hubble constant and the expansion history of the universe are key measurements provided by Type Ia supernovae. They were also instrumental in showing time dilation, which is a direct observational signature of expansion. Connections to explosion physics are made in the context of potential improvements of the quality of Type Ia supernovae as distance indicators. The coming years will see large efforts to use Type Ia supernovae to characterise dark energy.

  2. Properties and Alignment of Interstellar Dust Grains toward Type Ia Supernovae with Anomalous Polarization Curves

    Energy Technology Data Exchange (ETDEWEB)

    Hoang, Thiem, E-mail: thiemhoang@kasi.re.kr [Korea Astronomy and Space Science Institute 776, Daedeokdae-ro, Yuseong-gu, Daejeon 34055 (Korea, Republic of); Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George Street, Toronto, ON M5S 3H8 (Canada); Institute of Theoretical Physics, Goethe Universität Frankfurt, D-60438 Frankfurt am Main (Germany)

    2017-02-10

    Recent photometric and polarimetric observations of Type Ia supernovae (SNe Ia) show unusually low total-to-selective extinction ratios ( R {sub V} < 2) and wavelengths of maximum polarization ( λ{sub max} < 0.4 μ m) for several SNe Ia, which indicates peculiar properties of interstellar (IS) dust in the SN-hosted galaxies and/or the presence of circumstellar (CS) dust. In this paper, we use an inversion technique to infer the best-fit grain size distribution and the alignment function of interstellar grains along the lines of sight toward four SNe Ia with anomalous extinction and polarization data (SN 1986G, SN 2006X, SN 2008fp, and SN 2014J). We find that to reproduce low values of R{sub V}, a significant enhancement in the mass of small grains of radius a < 0.1 μ m is required. For SN 2014J, a simultaneous fit to its observed extinction and polarization is unsuccessful if all the data are attributed to IS dust (model 1), but a good fit is obtained when accounting for the contribution of CS dust (model 2). For SN 2008fp, our best-fit results for model 1 show that in order to reproduce an extreme value of λ{sub max} ∼ 0.15 μ m, small silicate grains must be aligned as efficiently as big grains. For this case, we suggest that strong radiation from the SN can induce efficient alignment of small grains in a nearby intervening molecular cloud via the radiative torque (RAT) mechanism. The resulting time dependence polarization from this RAT alignment model can be tested by observing at ultraviolet wavelengths.

  3. TYPE Ia SUPERNOVA CARBON FOOTPRINTS

    International Nuclear Information System (INIS)

    Thomas, R. C.; Nugent, P.; Aldering, G.; Aragon, C.; Bailey, S.; Childress, M.; Fakhouri, H. K.; Hsiao, E. Y.; Loken, S.; Antilogus, P.; Bongard, S.; Canto, A.; Baltay, C.; Buton, C.; Kerschhaggl, M.; Kowalski, M.; Paech, K.; Chotard, N.; Copin, Y.; Gangler, E.

    2011-01-01

    We present convincing evidence of unburned carbon at photospheric velocities in new observations of five Type Ia supernovae (SNe Ia) obtained by the Nearby Supernova Factory. These SNe are identified by examining 346 spectra from 124 SNe obtained before +2.5 days relative to maximum. Detections are based on the presence of relatively strong C II λ6580 absorption 'notches' in multiple spectra of each SN, aided by automated fitting with the SYNAPPS code. Four of the five SNe in question are otherwise spectroscopically unremarkable, with ions and ejection velocities typical of SNe Ia, but spectra of the fifth exhibit high-velocity (v > 20, 000 km s –1 ) Si II and Ca II features. On the other hand, the light curve properties are preferentially grouped, strongly suggesting a connection between carbon-positivity and broadband light curve/color behavior: three of the five have relatively narrow light curves but also blue colors and a fourth may be a dust-reddened member of this family. Accounting for signal to noise and phase, we estimate that 22 +10 –6% of SNe Ia exhibit spectroscopic C II signatures as late as –5 days with respect to maximum. We place these new objects in the context of previously recognized carbon-positive SNe Ia and consider reasonable scenarios seeking to explain a physical connection between light curve properties and the presence of photospheric carbon. We also examine the detailed evolution of the detected carbon signatures and the surrounding wavelength regions to shed light on the distribution of carbon in the ejecta. Our ability to reconstruct the C II λ6580 feature in detail under the assumption of purely spherical symmetry casts doubt on a 'carbon blobs' hypothesis, but does not rule out all asymmetric models. A low volume filling factor for carbon, combined with line-of-sight effects, seems unlikely to explain the scarcity of detected carbon in SNe Ia by itself.

  4. [Type IA glycogenosis with acute pancreatitis].

    Science.gov (United States)

    Herman, T E

    1995-01-01

    Type IA glycogenosis, or von Gierke disease, is the most common among the glycogenoses with enlarged liver. Acute pancreatitis is a rare manifestation of type IA glycogenosis and has been attributed to elevated serum fat levels. We report a case of type IA glycogenosis with acute pancreatitis. The radiologists should be familiar with the computed tomography findings in this rare complications of type IA glycogenosis.

  5. Cosmology with type-Ia supernovae

    OpenAIRE

    Miquel, Ramon

    2007-01-01

    I review the use of type-Ia supernovae (SNe) for cosmological studies. After briefly recalling the main features of type-Ia SNe that lead to their use as cosmological probes, I briefly describe current and planned type-Ia SNe surveys, with special emphasis on their physics reach in the presence of systematic uncertainties, which will be dominant in nearly all cases.

  6. Pregnancies in glycogen storage disease type Ia

    NARCIS (Netherlands)

    Martens, Danielle H. J.; Rake, Jan Peter; Schwarz, Martin; Ullrich, Kurt; Weinstein, David A.; Merkel, Martin; Sauer, Pieter J. J.; Smit, G. Peter A.

    OBJECTIVE: Reports on pregnancies in women with glycogen storage disease type Ia (GSD-Ia) are scarce. Because of improved life expectancy, pregnancy is becoming an important issue. We describe 15 pregnancies by focusing on dietary treatment, biochemical parameters, and GSD-Ia complications. STUDY

  7. THE AGES OF TYPE Ia SUPERNOVA PROGENITORS

    International Nuclear Information System (INIS)

    Brandt, Timothy D.; Aubourg, Eric; Strauss, Michael A.; Tojeiro, Rita; Heavens, Alan; Jimenez, Raul

    2010-01-01

    Using light curves and host galaxy spectra of 101 Type Ia supernovae (SNe Ia) with redshift z ∼ 2.4 Gyr. We find that each channel contributes roughly half of the Type Ia rate in our reference sample. We also construct the average spectra of high-stretch and low-stretch SN Ia host galaxies, and find that the difference of these spectra looks like a main-sequence B star with nebular emission lines indicative of star formation. This supports our finding that there are two populations of SNe Ia, and indicates that the progenitors of high-stretch supernovae are at the least associated with very recent star formation in the last few tens of Myr. Our results provide valuable constraints for models of Type Ia progenitors and may help improve the calibration of SNe Ia as standard candles.

  8. DETERMINING TYPE Ia SUPERNOVA HOST GALAXY EXTINCTION PROBABILITIES AND A STATISTICAL APPROACH TO ESTIMATING THE ABSORPTION-TO-REDDENING RATIO R{sub V}

    Energy Technology Data Exchange (ETDEWEB)

    Cikota, Aleksandar [European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748 Garching b. München (Germany); Deustua, Susana [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Marleau, Francine, E-mail: acikota@eso.org [Institute for Astro- and Particle Physics, University of Innsbruck, Technikerstrasse 25/8, A-6020 Innsbruck (Austria)

    2016-03-10

    We investigate limits on the extinction values of Type Ia supernovae (SNe Ia) to statistically determine the most probable color excess, E(B – V), with galactocentric distance, and use these statistics to determine the absorption-to-reddening ratio, R{sub V}, for dust in the host galaxies. We determined pixel-based dust mass surface density maps for 59 galaxies from the Key Insight on Nearby Galaxies: a Far-infrared Survey with Herschel (KINGFISH). We use SN Ia spectral templates to develop a Monte Carlo simulation of color excess E(B – V) with R{sub V} = 3.1 and investigate the color excess probabilities E(B – V) with projected radial galaxy center distance. Additionally, we tested our model using observed spectra of SN 1989B, SN 2002bo, and SN 2006X, which occurred in three KINGFISH galaxies. Finally, we determined the most probable reddening for Sa–Sap, Sab–Sbp, Sbc–Scp, Scd–Sdm, S0, and irregular galaxy classes as a function of R/R{sub 25}. We find that the largest expected reddening probabilities are in Sab–Sb and Sbc–Sc galaxies, while S0 and irregular galaxies are very dust poor. We present a new approach for determining the absorption-to-reddening ratio R{sub V} using color excess probability functions and find values of R{sub V} = 2.71 ± 1.58 for 21 SNe Ia observed in Sab–Sbp galaxies, and R{sub V} = 1.70 ± 0.38, for 34 SNe Ia observed in Sbc–Scp galaxies.

  9. Dark Matter Ignition of Type Ia Supernovae.

    Science.gov (United States)

    Bramante, Joseph

    2015-10-02

    Recent studies of low redshift type Ia supernovae (SN Ia) indicate that half explode from less than Chandrasekhar mass white dwarfs, implying ignition must proceed from something besides the canonical criticality of Chandrasekhar mass SN Ia progenitors. We show that 1-100 PeV mass asymmetric dark matter, with imminently detectable nucleon scattering interactions, can accumulate to the point of self-gravitation in a white dwarf and collapse, shedding gravitational potential energy by scattering off nuclei, thereby heating the white dwarf and igniting the flame front that precedes SN Ia. We combine data on SN Ia masses with data on the ages of SN Ia-adjacent stars. This combination reveals a 2.8σ inverse correlation between SN Ia masses and ignition ages, which could result from increased capture of dark matter in 1.4 vs 1.1 solar mass white dwarfs. Future studies of SN Ia in galactic centers will provide additional tests of dark-matter-induced type Ia ignition. Remarkably, both bosonic and fermionic SN Ia-igniting dark matter also resolve the missing pulsar problem by forming black holes in ≳10  Myr old pulsars at the center of the Milky Way.

  10. Improvements to type Ia supernova models

    Science.gov (United States)

    Saunders, Clare M.

    Type Ia Supernovae provided the first strong evidence of dark energy and are still an important tool for measuring the accelerated expansion of the universe. However, future improvements will be limited by systematic uncertainties in our use of Type Ia supernovae as standard candles. Using Type Ia supernovae for cosmology relies on our ability to standardize their absolute magnitudes, but this relies on imperfect models of supernova spectra time series. This thesis is focused on using data from the Nearby Supernova Factory both to understand current sources of uncertainty in standardizing Type Ia supernovae and to develop techniques that can be used to limit uncertainty in future analyses. (Abstract shortened by ProQuest.).

  11. Rates and progenitors of type Ia supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Wood-Vasey, William Michael [Univ. of California, Berkeley, CA (United States)

    2004-01-01

    The remarkable uniformity of Type Ia supernovae has allowed astronomers to use them as distance indicators to measure the properties and expansion history of the Universe. However, Type Ia supernovae exhibit intrinsic variation in both their spectra and observed brightness. The brightness variations have been approximately corrected by various methods, but there remain intrinsic variations that limit the statistical power of current and future observations of distant supernovae for cosmological purposes. There may be systematic effects in this residual variation that evolve with redshift and thus limit the cosmological power of SN Ia luminosity-distance experiments. To reduce these systematic uncertainties, we need a deeper understanding of the observed variations in Type Ia supernovae. Toward this end, the Nearby Supernova Factory has been designed to discover hundreds of Type Ia supernovae in a systematic and automated fashion and study them in detail. This project will observe these supernovae spectrophotometrically to provide the homogeneous high-quality data set necessary to improve the understanding and calibration of these vital cosmological yardsticks. From 1998 to 2003, in collaboration with the Near-Earth Asteroid Tracking group at the Jet Propulsion Laboratory, a systematic and automated searching program was conceived and executed using the computing facilities at Lawrence Berkeley National Laboratory and the National Energy Research Supercomputing Center. An automated search had never been attempted on this scale. A number of planned future large supernovae projects are predicated on the ability to find supernovae quickly, reliably, and efficiently in large datasets. A prototype run of the SNfactory search pipeline conducted from 2002 to 2003 discovered 83 SNe at a final rate of 12 SNe/month. A large, homogeneous search of this scale offers an excellent opportunity to measure the rate of Type Ia supernovae. This thesis presents a new method for

  12. Rates and progenitors of type Ia supernovae

    International Nuclear Information System (INIS)

    Wood-Vasey, William Michael

    2004-01-01

    The remarkable uniformity of Type Ia supernovae has allowed astronomers to use them as distance indicators to measure the properties and expansion history of the Universe. However, Type Ia supernovae exhibit intrinsic variation in both their spectra and observed brightness. The brightness variations have been approximately corrected by various methods, but there remain intrinsic variations that limit the statistical power of current and future observations of distant supernovae for cosmological purposes. There may be systematic effects in this residual variation that evolve with redshift and thus limit the cosmological power of SN Ia luminosity-distance experiments. To reduce these systematic uncertainties, we need a deeper understanding of the observed variations in Type Ia supernovae. Toward this end, the Nearby Supernova Factory has been designed to discover hundreds of Type Ia supernovae in a systematic and automated fashion and study them in detail. This project will observe these supernovae spectrophotometrically to provide the homogeneous high-quality data set necessary to improve the understanding and calibration of these vital cosmological yardsticks. From 1998 to 2003, in collaboration with the Near-Earth Asteroid Tracking group at the Jet Propulsion Laboratory, a systematic and automated searching program was conceived and executed using the computing facilities at Lawrence Berkeley National Laboratory and the National Energy Research Supercomputing Center. An automated search had never been attempted on this scale. A number of planned future large supernovae projects are predicated on the ability to find supernovae quickly, reliably, and efficiently in large datasets. A prototype run of the SNfactory search pipeline conducted from 2002 to 2003 discovered 83 SNe at a final rate of 12 SNe/month. A large, homogeneous search of this scale offers an excellent opportunity to measure the rate of Type Ia supernovae. This thesis presents a new method for

  13. The Evolution of the Type Ia Supernova Luminosity Function

    NARCIS (Netherlands)

    Shen, K.J.; Toonen, S.; Graur, O.

    2017-01-01

    Type Ia supernovae (SNe Ia) exhibit a wide diversity of peak luminosities and light curve shapes: the faintest SNe Ia are 10 times less luminous and evolve more rapidly than the brightest SNe Ia. Their differing characteristics also extend to their stellar age distributions, with fainter SNe Ia

  14. Prepubertal growth in congenital disorder of glycosylation type Ia (CDG-Ia)

    OpenAIRE

    Kjaergaard, S; Muller, J; Skovby, F

    2002-01-01

    Aims: To delineate the pattern of growth in prepubertal children with congenital disorder of glycosylation type Ia (CDG-Ia) in order to identify critical period(s) and possible cause(s) of growth failure.

  15. Observations of Type Ia Supernovae, and Challenges for Cosmology

    OpenAIRE

    Li, Weidong; Filippenko, Alexei V.

    2003-01-01

    Observations of Type Ia supernovae (SNe Ia) reveal correlations between their luminosities and light-curve shapes, and between their spectral sequence and photometric sequence. Assuming SNe Ia do not evolve at different redshifts, the Hubble diagram of SNe Ia may indicate an accelerating Universe, the signature of a cosmological constant or other forms of dark energy. Several studies raise concerns about the evolution of SNe Ia (e.g., the peculiarity rate, the risetime, and the color of SNe I...

  16. Stimulation of protective antibodies against type Ia and Ib group B streptococci by a type Ia polysaccharide-tetanus toxoid conjugate vaccine.

    OpenAIRE

    Wessels, M R; Paoletti, L C; Rodewald, A K; Michon, F; DiFabio, J; Jennings, H J; Kasper, D L

    1993-01-01

    Antisera elicited by type Ia group B streptococci (GBS) contain antibodies that react with both type Ia and type Ib strains. Previous studies suggested that antibodies elicited by type Ia organisms recognized a carbohydrate antigen or epitope common to Ia and Ib strains. We now report the synthesis and immunogenicity testing of a type Ia polysaccharide-tetanus toxoid (Ia-TT) conjugate vaccine. Ia-TT elicited type Ia polysaccharide-specific immunoglobulin G antibodies in all three of the rabbi...

  17. SHOCK BREAKOUT FROM TYPE Ia SUPERNOVA

    International Nuclear Information System (INIS)

    Piro, Anthony L.; Chang, Philip; Weinberg, Nevin N.

    2010-01-01

    The mode of explosive burning in Type Ia supernovae (SNe Ia) remains an outstanding problem. It is generally thought to begin as a subsonic deflagration, but this may transition into a supersonic detonation (the delayed detonation transition, DDT). We argue that this transition leads to a breakout shock, which would provide the first unambiguous evidence that DDTs occur. Its main features are a hard X-ray flash (∼20 keV) lasting ∼10 -2 s with a total radiated energy of ∼10 40 erg, followed by a cooling tail. This creates a distinct feature in the visual light curve, which is separate from the nickel decay. This cooling tail has a maximum absolute visual magnitude of M V ∼ -9 to -10 at ∼1 day, which depends most sensitively on the white dwarf radius at the time of the DDT. As the thermal diffusion wave moves in, the composition of these surface layers may be imprinted as spectral features, which would help to discern between SN Ia progenitor models. Since this feature should accompany every SNe Ia, future deep surveys (e.g., m = 24) will see it out to a distance of ∼80 Mpc, giving a maximum rate of ∼60 yr -1 . Archival data sets can also be used to study the early rise dictated by the shock heating (at ∼20 days before maximum B-band light). A similar and slightly brighter event may also accompany core bounce during the accretion-induced collapse to a neutron star, but with a lower occurrence rate.

  18. Sensitivity studies for supernovae type Ia

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Thien Tam; Goebel, Kathrin; Reifarth, Rene [Goethe University Frankfurt am Main (Germany); Calder, Alan [SUNY - Department of Physics and Astronomy, New York (United States); Pignatari, Marco [Konkoly Observatory of the Hungarian Academy of Sciences (Hungary); Townsley, Dean [The University of Alabama (United States); Travaglio, Claudia [INAF - Astrophysical Observatory, Turin (Italy); Collaboration: NuGrid collaboration

    2016-07-01

    The NuGrid research platform provides a simulation framework to study the nucleosynthesis in multi-dimensional Supernovae Type Ia models. We use a large network of over 5,000 isotopes and more than 60,000 reactions. The nucleosynthesis is investigated in post-processing simulations with temperature and density profiles, initial abundance distributions and a set of reaction rates as input. The sensitivity of the isotopic abundances to α-, proton-, and neutron-capture reaction, their inverse reactions, as well as fusion reactions were investigated. First results have been achieved for different mass coordinates of the exploding star.

  19. The Distant Type Ia Supernova Rate

    Science.gov (United States)

    Pain, R.; Fabbro, S.; Sullivan, M.; Ellis, R. S.; Aldering, G.; Astier, P.; Deustua, S. E.; Fruchter, A. S.; Goldhaber, G.; Goobar, A.; Groom, D. E.; Hardin, D.; Hook, I. M.; Howell, D. A.; Irwin, M. J.; Kim, A. G.; Kim, M. Y.; Knop, R. A.; Lee, J. C.; Perlmutter, S.; Ruiz-Lapuente, P.; Schahmaneche, K.; Schaefer, B.; Walton, N. A.

    2002-05-28

    We present a measurement of the rate of distant Type Ia supernovae derived using 4 large subsets of data from the Supernova Cosmology Project. Within this fiducial sample, which surveyed about 12 square degrees, thirty-eight supernovae were detected at redshifts 0.25--0.85. In a spatially flat cosmological model consistent with the results obtained by the Supernova Cosmology Project, we derive a rest-frame Type Ia supernova rate at a mean red shift z {approx_equal} 0.55 of 1.53 {sub -0.25}{sub -0.31}{sup 0.28}{sup 0.32} x 10{sup -4} h{sup 3} Mpc{sup -3} yr{sup -1} or 0.58{sub -0.09}{sub -0.09}{sup +0.10}{sup +0.10} h{sup 2} SNu(1 SNu = 1 supernova per century per 10{sup 10} L{sub B}sun), where the first uncertainty is statistical and the second includes systematic effects. The dependence of the rate on the assumed cosmological parameters is studied and the redshift dependence of the rate per unit comoving volume is contrasted with local estimates in the context of possible cosmic star formation histories and progenitor models.

  20. Constraining Cosmic Evolution of Type Ia Supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Foley, Ryan J.; Filippenko, Alexei V.; Aguilera, C.; Becker, A.C.; Blondin, S.; Challis, P.; Clocchiatti, A.; Covarrubias, R.; Davis, T.M.; Garnavich, P.M.; Jha, S.; Kirshner, R.P.; Krisciunas, K.; Leibundgut, B.; Li, W.; Matheson, T.; Miceli, A.; Miknaitis, G.; Pignata, G.; Rest, A.; Riess, A.G.; /UC, Berkeley, Astron. Dept. /Cerro-Tololo InterAmerican Obs. /Washington U., Seattle, Astron. Dept. /Harvard-Smithsonian Ctr. Astrophys. /Chile U., Catolica /Bohr Inst. /Notre Dame U. /KIPAC, Menlo Park /Texas A-M /European Southern Observ. /NOAO, Tucson /Fermilab /Chile U., Santiago /Harvard U., Phys. Dept. /Baltimore, Space Telescope Sci. /Johns Hopkins U. /Res. Sch. Astron. Astrophys., Weston Creek /Stockholm U. /Hawaii U. /Illinois U., Urbana, Astron. Dept.

    2008-02-13

    We present the first large-scale effort of creating composite spectra of high-redshift type Ia supernovae (SNe Ia) and comparing them to low-redshift counterparts. Through the ESSENCE project, we have obtained 107 spectra of 88 high-redshift SNe Ia with excellent light-curve information. In addition, we have obtained 397 spectra of low-redshift SNe through a multiple-decade effort at Lick and Keck Observatories, and we have used 45 ultraviolet spectra obtained by HST/IUE. The low-redshift spectra act as a control sample when comparing to the ESSENCE spectra. In all instances, the ESSENCE and Lick composite spectra appear very similar. The addition of galaxy light to the Lick composite spectra allows a nearly perfect match of the overall spectral-energy distribution with the ESSENCE composite spectra, indicating that the high-redshift SNe are more contaminated with host-galaxy light than their low-redshift counterparts. This is caused by observing objects at all redshifts with similar slit widths, which corresponds to different projected distances. After correcting for the galaxy-light contamination, subtle differences in the spectra remain. We have estimated the systematic errors when using current spectral templates for K-corrections to be {approx}0.02 mag. The variance in the composite spectra give an estimate of the intrinsic variance in low-redshift maximum-light SN spectra of {approx}3% in the optical and growing toward the ultraviolet. The difference between the maximum-light low and high-redshift spectra constrain SN evolution between our samples to be < 10% in the rest-frame optical.

  1. Near Infrared and bolometric properties of Type Ia supernovae

    OpenAIRE

    Dhawan, Suhail

    2017-01-01

    Type Ia supernovae (SN Ia) are excellent tools for modern cosmology. Their calibrated peak luminosities have been used to discover the accelerated expansion of the universe. SN Ia are also interesting astrophysical sources as endpoints of stellar evolution. In this thesis, I analyse the near infrared and bolometric properties of SN Ia and use the properties of their light curves to derive estimates for global parameters, like the total Ni mass, and improve upon their use as distance indicator...

  2. Type Ia Supernovae: Their Origin and Possible Applications in Cosmology

    OpenAIRE

    Nomoto, Ken'ichi; Iwamoto, Koichi; Kishimoto, Nobuhiro

    1997-01-01

    Spectroscopic and photometric evidence indicates that Type Ia supernovae (SNe Ia) are the thermonuclear explosions of accreting white dwarfs. However, the progenitor binary systems and hydrodynamical models for SNe Ia are still controversial. The relatively uniform light curves and spectral evolution of SNe Ia have led to their use as a standard candle for determining cosmological parameters, such as the Hubble constant, the density parameter, and the cosmological constant. Recent progress in...

  3. DARK MATTER ADMIXED TYPE Ia SUPERNOVAE

    International Nuclear Information System (INIS)

    Leung, S.-C.; Chu, M.-C.; Lin, L.-M.

    2015-01-01

    We perform two-dimensional hydrodynamic simulations for the thermonuclear explosion of Chandrasekhar-mass white dwarfs with dark matter (DM) cores in Newtonian gravity. We include a 19-isotope nuclear reaction network and make use of the pure turbulent deflagration model as the explosion mechanism in our simulations. Our numerical results show that the general properties of the explosion depend quite sensitively on the mass of the DM core M DM : a larger M DM generally leads to a weaker explosion and a lower mass of synthesized iron-peaked elements. In particular, the total mass of produced can drop from about 0.3 to 0.03 M ⊙ as M DM increases from 0.01 to 0.03 M ⊙ . We have also constructed the bolometric light curves obtained from our simulations and found that our results match well with the observational data of sub-luminous Type Ia supernovae

  4. EVOLVING TO TYPE Ia SUPERNOVAE WITH SHORT DELAY TIMES

    International Nuclear Information System (INIS)

    Wang Bo; Chen Xuefei; Han Zhanwen; Meng Xiangcun

    2009-01-01

    The single-degenerate model is currently a favorable progenitor model for Type Ia supernovae (SNe Ia). Recent investigations on the white dwarf (WD) + He star channel of the single-degenerate model imply that this channel is noteworthy for producing SNe Ia. In this paper, we studied SN Ia birthrates and delay times of this channel via a detailed binary population synthesis approach. We found that the Galactic SN Ia birthrate from the WD + He star channel is ∼0.3 x 10 -3 yr -1 according to our standard model, and that this channel can explain SNe Ia with short delay times (∼4.5 x 10 7 -1.4 x 10 8 yr). Meanwhile, these WD + He star systems may be related to the young supersoft X-ray sources prior to SN Ia explosions.

  5. Type Ia supernovae: their origin and possible applications in cosmology.

    Science.gov (United States)

    Nomoto, K; Iwamoto, K; Kishimoto, N

    1997-05-30

    Spectroscopic and photometric evidence indicates that Type Ia supernovae (SNe Ia) are the thermonuclear explosions of accreting white dwarfs. However, the progenitor binary systems and hydrodynamical models for SNe Ia are still controversial. The relatively uniform light curves and spectral evolution of SNe Ia have led to their use as a standard candle for determining cosmological parameters, such as the Hubble constant, the density parameter, and the cosmological constant. Recent progress includes the calibration of the absolute maximum brightness of SNe Ia with the Hubble Space Telescope, the reduction of the dispersion in the Hubble diagram through the use of the relation between the light curve shape and the maximum brightness of SNe Ia, and the discovery of many SNe Ia with high red shifts.

  6. Molecular analysis of glycogen storage disease type Ia in Iranian ...

    Indian Academy of Sciences (India)

    [Mahmoud S. K., Khorrami A., Rafeey M., Ghergherehchi R. and Sima M. D. 2017 Molecular analysis of glycogen storage disease type Ia in Iranian Azeri ... G6PC gene; Azeri Turkish; glycogen storage disease type Ia; novel mutation; Azeri Turkish sequencing. ... Approximately 5 ml of intravenous blood samples were col-.

  7. TURBULENT OXYGEN FLAMES IN TYPE Ia SUPERNOVAE

    International Nuclear Information System (INIS)

    Aspden, A. J.; Bell, J. B.; Woosley, S. E.

    2011-01-01

    In previous studies, we examined turbulence-flame interactions in carbon-burning thermonuclear flames in Type Ia supernovae. In this study, we consider turbulence-flame interactions in the trailing oxygen flames. The two aims of the paper are to examine the response of the inductive oxygen flame to intense levels of turbulence, and to explore the possibility of transition to detonation in the oxygen flame. Scaling arguments analogous to the carbon flames are presented and then compared against three-dimensional simulations for a range of Damkoehler numbers (Da 16 ) at a fixed Karlovitz number. The simulations suggest that turbulence does not significantly affect the oxygen flame when Da 16 16 >1, turbulence enhances heat transfer and drives the propagation of a flame that is narrower than the corresponding inductive flame would be. Furthermore, burning under these conditions appears to occur as part of a combined carbon-oxygen turbulent flame with complex compound structure. The simulations do not appear to support the possibility of a transition to detonation in the oxygen flame, but do not preclude it either.

  8. Two classes of fast-declining Type Ia supernovae

    Science.gov (United States)

    Dhawan, Suhail; Leibundgut, B.; Spyromilio, J.; Blondin, S.

    2017-06-01

    We aim to characterise a sample of fast-declining Type Ia supernovae (SN Ia) using their bolometric and near-infrared (NIR) properties. Based on these properties, we find that fast-declining SN Ia separate into two categories based on their bolometric and NIR properties. The peak bolometric luminosity (Lmax), the phase of the first maximum relative to the optical, the NIR peak luminosity, and the occurrence of a second maximum in the NIR distinguish a group of very faint SN Ia. Fast-declining supernovae show a large range of peak bolometric luminosities (Lmax differing by up to a factor of 8). All fast-declining SN Ia with Lmax 0.5× 1043 erg s-1 appear to smoothly connect to normal SN Ia. The total ejecta mass (Mej) values for SNe with enough late time data are ≲1 M⊙, indicating a sub-Chandrasekhar mass progenitor for these SNe.

  9. Theoretical uncertainties of the Type Ia supernova rate

    NARCIS (Netherlands)

    Claeys, J.S.W.; Pols, O.R.; Izzard, R.G.; Vink, J.; Verbunt, F.W.M.

    2014-01-01

    It is thought that Type Ia supernovae (SNe Ia) are explosions of carbon-oxygen white dwarfs (CO WDs). Two main evolutionary channels are proposed for the WD to reach the critical density required for a thermonuclear explosion: the single degenerate (SD) scenario, in which a CO WD accretes from a

  10. Pregnancies in Glycogen Storage Disease Type Ia

    Science.gov (United States)

    Martens, Daniëlle HJ; Rake, Jan Peter; Schwarz, Martin; Ullrich, Kurt; Weinstein, David A; Merkel, Martin; Sauer, Pieter JJ; Smit, G Peter A

    2013-01-01

    Objective Reports on pregnancies in women with GSD-Ia are scarce. Due to improved life expectancy, pregnancy is becoming an important issue. We describe 15 pregnancies focusing on dietary treatment, biochemical parameters and GSD-Ia complications. Study Design Carbohydrate requirements (mg/kg/min), triglyceride and uric acid levels, liver ultrasonography and creatinine clearance were investigated before, during and after pregnancy. Data of the newborns were obtained from the records. Results In the first trimester, a significant increase in carbohydrate requirements was observed (p=0,007). Most patients had acceptable triglyceride and uric acid levels during pregnancy. No increase in size/number of adenomas was seen. In 3/4 patients, a decrease in GFR was observed after pregnancy. In three pregnancies, lactic acidosis developed during delivery with severe multi-organ failure in one. All but one of the children are healthy and show good psychomotor development. Conclusion Successful pregnancies are possible in GSD-Ia patients, although specific GSD-Ia related risks are present. PMID:18241814

  11. Search for surviving companions in type Ia supernova remnants

    International Nuclear Information System (INIS)

    Pan, Kuo-Chuan; Ricker, Paul M.; Taam, Ronald E.

    2014-01-01

    The nature of the progenitor systems of type Ia supernovae (SNe Ia) is still unclear. One way to distinguish between the single-degenerate scenario and double-degenerate scenario for their progenitors is to search for the surviving companions (SCs). Using a technique that couples the results from multi-dimensional hydrodynamics simulations with calculations of the structure and evolution of main-sequence- (MS-) and helium-rich SCs, the color and magnitude of MS- and helium-rich SCs are predicted as functions of time. The SC candidates in Galactic type Ia supernova remnants (Ia SNR) and nearby extragalactic Ia SNRs are discussed. We find that the maximum detectable distance of MS SCs (helium-rich SCs) is 0.6-4 Mpc (0.4-16 Mpc), if the apparent magnitude limit is 27 in the absence of extinction, suggesting that the Large and Small Magellanic Clouds and the Andromeda Galaxy are excellent environments in which to search for SCs. However, only five Ia SNRs have been searched for SCs, showing little support for the standard channels in the singe-degenerate scenario. To better understand the progenitors of SNe Ia, we encourage the search for SCs in other nearby Ia SNRs.

  12. Ejecta mass diagnostics of Type Ia supernovae

    Science.gov (United States)

    Wilk, Kevin D.; Hillier, D. John; Dessart, Luc

    2018-03-01

    We present one-dimensional non-local thermodynamic equilibrium time-dependent radiative transfer simulations (using CMFGEN) of two sub-Chandrasekhar (sub-MCh), one MCh and one super-MCh Type Ia SN ejecta models. Three originate from MCh delayed detonation models, and the fourth is a sub-MCh detonation model. Ejecta masses are 1.02, 1.04, 1.40 and 1.70 M⊙, and all models have 0.62 M⊙ of 56Ni. Sub-MCh model light curves evolve faster, reaching bolometric maximum 2-3 d earlier and having 3-4 d shorter bolometric half-light widths. The models vary by ˜12 per cent at maximum bolometric luminosity and by 0.17 mag in Bmax. While ΔM15(B) increases with ejecta mass, it only varies by ˜5 per cent around 1 mag. Sub-MCh models are 0.25 mag bluer in B - R at Bmax. Optical spectra share many similarities, but lower mass models exhibit less UV line blanketing during the photospheric phase. At nebular times, significant near-infrared (NIR) spectroscopic differences are seen. In particular, emission lines of the Ca II NIR triplet; [S III] λλ9068,9530; [Ca II] λλ7291,7324; [Ar III] λλ7135,7751 and [Ni II] 1.939 μm are stronger in higher mass models. The [Ni II] 1.939 μm line is absent in the sub-MCh detonation model, and provides a valuable potential tool to distinguish sub-MCh explosions from MCh explosions. In general, the nebular phase models are too highly ionized. We attribute this to the neglect of clumping and/or the distribution of intermediate mass and iron group elements. The two sub-MCh models, while exploded by different mechanisms, can be distinguished in the J and H bands at late times (e.g. +200 d).

  13. DISTRIBUTED FLAMES IN TYPE Ia SUPERNOVAE

    International Nuclear Information System (INIS)

    Aspden, A. J.; Bell, J. B.; Woosley, S. E.

    2010-01-01

    At a density near a few x10 7 g cm -3 , the subsonic burning in a Type Ia supernova (SN) enters the distributed regime (high Karlovitz number). In this regime, turbulence disrupts the internal structure of the flame, and so the idea of laminar burning propagated by conduction is no longer valid. The nature of the burning in this distributed regime depends on the turbulent Damkoehler number (Da T ), which steadily declines from much greater than one to less than one as the density decreases to a few x10 6 g cm -3 . Classical scaling arguments predict that the turbulent flame speed s T , normalized by the turbulent intensity u-check, follows s T /u-check = Da T 1/2 for Da T ∼ T ∼ 1, and the flame burns as a turbulently broadened effective unity Lewis number flame. This flame burns locally with speed s λ and width l λ , and we refer to this kind of flame as a λ-flame. The burning becomes a collection of λ-flames spread over a region approximately the size of the integral scale. While the total burning rate continues to have a well-defined average, s T ∼u-check, the burning is unsteady. We present a theoretical framework, supported by both one-dimensional and three-dimensional numerical simulations, for the burning in these two regimes. Our results indicate that the average value of s T can actually be roughly twice u-check for Da T ∼> 1, and that localized excursions to as much as 5 times u-check can occur. We also explore the properties of the individual flames, which could be sites for a transition to detonation when Da T ∼ 1. The λ-flame speed and width can be predicted based on the turbulence in the star (specifically the energy dissipation rate ε*) and the turbulent nuclear burning timescale of the fuel τ T nuc . We propose a practical method for measuring s λ and l λ based on the scaling relations and small-scale computationally inexpensive simulations. This suggests that a simple turbulent flame model can be easily constructed suitable for

  14. Asymmetric Explosion of Type Ia Supernovae and Their Observational Signatures

    International Nuclear Information System (INIS)

    Maeda, Keiichi

    2010-01-01

    The nature of Type Ia supernova (SN Ia) explosions has not yet been clarified, despite their importance in astrophysics and cosmology. Recent theoretical investigations suggest that asymmetric distribution of initial thermonuclear sparks may be a key in the SN Ia explosion mechanism. In this paper, the first observational evidence of the asymmetry in SN Ia explosions is presented: We have found that late-time nebular spectra of various SNe Ia show a diversity in wavelengths of emission lines. This feature is inconsistent with any spherically symmetric explosion models, and indicates that the innermost region, a likely product of the deflagration wave propagation, shows an off-set with respect to the explosion center. The diversity in the emission-line wavelengths could naturally be explained by a combination of different viewing angles.

  15. A problem with the analysis of type Ia supernovae

    Science.gov (United States)

    Crawford, David F.

    2017-12-01

    Type Ia supernovae have light curves that have widths and magnitudes that can be used for testing cosmologies and they provide one of the few direct measurements of time dilation. It is shown that the standard analysis that calibrates the light curve against a rest-frame average (such as SALT2) removes all the cosmological information from the calibrated light curves. Consequently type Ia supernovae calibrated with these methods cannot be used to investigate cosmology. The major evidence that supports the hypothesis of a static universe is that the measurements of the widths of the rawlight curves of type Ia supernovae do not show any time dilation. The intrinsicwavelength dependence shown by the SALT2 calibration templates is also consistent with no time dilation. Using a static cosmological model the peak absolute magnitudes of raw type Ia supernovae observations are also independent of redshift. These results support the hypothesis of a static universe.

  16. Two populations of progenitors for Type Ia supernovae?

    Science.gov (United States)

    Mannucci, F.; Della Valle, M.; Panagia, N.

    2006-08-01

    We use recent observations of the evolution of the Type Ia supernova (SN Ia) rate with redshift, the dependence of the SN Ia rate on the colours of the parent galaxies, and the enhancement of the SN Ia rate in radio-loud early-type galaxies to derive on robust empirical grounds, the delay time distribution (DTD) between the formation of the progenitor star and its explosion as an SN. Our analysis finds: (i) delay times as long as 3-4 Gyr, derived from observations of SNe Ia at high redshift, cannot reproduce the dependence of the SN Ia rate on the colours and on the radio-luminosity of the parent galaxies, as observed in the local Universe; (ii) the comparison between observed SN rates and a grid of theoretical `single-population' DTDs shows that only a few of them are possibly consistent with observations. The most successful models are all predicting a peak of SN explosions soon after star formation and an extended tail in the DTD, and can reproduce the data but only at a modest statistical confidence level; (iii) present data are best matched by a bimodal DTD, in which about 50 per cent of SNe Ia (dubbed `prompt' SNe Ia) explode soon after their stellar birth, in a time of the order of 108 yr, while the remaining 50 per cent (`tardy' SNe Ia) have a much wider distribution, well described by an exponential function with a decay time of about 3 Gyr. The presence in the DTD of both a strong peak at early times and a prolonged exponential tail, coupled with the well-established bimodal distribution of the decay rate (Δm15) and the systematic difference observed in the expansion velocities of the ejecta of SNe Ia in ellipticals and spirals, suggests the existence of two classes of progenitors. We discuss the cosmological implications of this result and make simple predictions, which are testable with future instrumentation.

  17. Molecular prenatal diagnosis of glycogen storage disease type Ia.

    Science.gov (United States)

    Qu, Y; Abdenur, J E; Eng, C M; Desnick, R J

    1996-04-01

    Glycogen storage disease type Ia (GSD Ia, von Gierke disease) is an autosomal recessive inborn error of metabolism caused by the deficiency of D-glucose-6-phosphatase (G6Pase). Since this enzyme is expressed primarily in hepatocytes, couples at risk for GSD type Ia relied on fetal liver biopsy for prenatal diagnosis. The recent isolation of the G6Pase gene and identification of several disease-causing mutations have permitted molecular prenatal diagnosis using amniocytes or chorionic villi. Chorionic villus sampling (CVS) was performed in an Ashkenazi Jewish family in whom a previous child was homoallelic and both parents were heterozygous for the R83C mutation. Molecular analysis revealed that the fetus was not affected. The prenatal diagnosis was confirmed postnatally by biochemical and molecular studies. Thus, the molecular prenatal diagnosis of GSD type Ia can be safely and accurately made in the first trimester.

  18. HOW TO FIND GRAVITATIONALLY LENSED TYPE Ia SUPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Goldstein, Daniel A.; Nugent, Peter E. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States)

    2017-01-01

    Type Ia supernovae (SNe Ia) that are multiply imaged by gravitational lensing can extend the SN Ia Hubble diagram to very high redshifts ( z ≳ 2), probe potential SN Ia evolution, and deliver high-precision constraints on H {sub 0}, w , and Ω{sub m} via time delays. However, only one, iPTF16geu, has been found to date, and many more are needed to achieve these goals. To increase the multiply imaged SN Ia discovery rate, we present a simple algorithm for identifying gravitationally lensed SN Ia candidates in cadenced, wide-field optical imaging surveys. The technique is to look for supernovae that appear to be hosted by elliptical galaxies, but that have absolute magnitudes implied by the apparent hosts’ photometric redshifts that are far brighter than the absolute magnitudes of normal SNe Ia (the brightest type of supernovae found in elliptical galaxies). Importantly, this purely photometric method does not require the ability to resolve the lensed images for discovery. Active galactic nuclei, the primary sources of contamination that affect the method, can be controlled using catalog cross-matches and color cuts. Highly magnified core-collapse SNe will also be discovered as a byproduct of the method. Using a Monte Carlo simulation, we forecast that the Large Synoptic Survey Telescope can discover up to 500 multiply imaged SNe Ia using this technique in a 10 year z -band search, more than an order of magnitude improvement over previous estimates. We also predict that the Zwicky Transient Facility should find up to 10 multiply imaged SNe Ia using this technique in a 3 year R -band search—despite the fact that this survey will not resolve a single system.

  19. The Influence of Host Galaxies in Type Ia Supernova Cosmology

    Science.gov (United States)

    Uddin, Syed A.; Mould, Jeremy; Lidman, Chris; Ruhlmann-Kleider, Vanina; Zhang, Bonnie R.

    2017-10-01

    We use a sample of 1338 spectroscopically confirmed and photometrically classified Type Ia supernovae (SNe Ia) sourced from Carnegie Supernova Project, Center for Astrophysics Supernova Survey, Sloan Digital Sky Survey-II, and SuperNova Legacy Survey SN samples to examine the relationships between SNe Ia and the galaxies that host them. Our results provide confirmation with improved statistical significance that SNe Ia, after standardization, are on average more luminous in massive hosts (significance >5σ), and decline more rapidly in massive hosts (significance >9σ) and in hosts with low specific star formation rates (significance >8σ). We study the variation of these relationships with redshift and detect no evolution. We split SNe Ia into pairs of subsets that are based on the properties of the hosts and fit cosmological models to each subset. Including both systematic and statistical uncertainties, we do not find any significant shift in the best-fit cosmological parameters between the subsets. Among different SN Ia subsets, we find that SNe Ia in hosts with high specific star formation rates have the least intrinsic scatter (σ int = 0.08 ± 0.01) in luminosity after standardization.

  20. Circumstellar material in type Ia supernovae via sodium absorption features.

    Science.gov (United States)

    Sternberg, A; Gal-Yam, A; Simon, J D; Leonard, D C; Quimby, R M; Phillips, M M; Morrell, N; Thompson, I B; Ivans, I; Marshall, J L; Filippenko, A V; Marcy, G W; Bloom, J S; Patat, F; Foley, R J; Yong, D; Penprase, B E; Beeler, D J; Allende Prieto, C; Stringfellow, G S

    2011-08-12

    Type Ia supernovae are key tools for measuring distances on a cosmic scale. They are generally thought to be the thermonuclear explosion of an accreting white dwarf in a close binary system. The nature of the mass donor is still uncertain. In the single-degenerate model it is a main-sequence star or an evolved star, whereas in the double-degenerate model it is another white dwarf. We show that the velocity structure of absorbing material along the line of sight to 35 type Ia supernovae tends to be blueshifted. These structures are likely signatures of gas outflows from the supernova progenitor systems. Thus, many type Ia supernovae in nearby spiral galaxies may originate in single-degenerate systems.

  1. A strong ultraviolet pulse from a newborn type Ia supernova.

    Science.gov (United States)

    Cao, Yi; Kulkarni, S R; Howell, D Andrew; Gal-Yam, Avishay; Kasliwal, Mansi M; Valenti, Stefano; Johansson, J; Amanullah, R; Goobar, A; Sollerman, J; Taddia, F; Horesh, Assaf; Sagiv, Ilan; Cenko, S Bradley; Nugent, Peter E; Arcavi, Iair; Surace, Jason; Woźniak, P R; Moody, Daniela I; Rebbapragada, Umaa D; Bue, Brian D; Gehrels, Neil

    2015-05-21

    Type Ia supernovae are destructive explosions of carbon-oxygen white dwarfs. Although they are used empirically to measure cosmological distances, the nature of their progenitors remains mysterious. One of the leading progenitor models, called the single degenerate channel, hypothesizes that a white dwarf accretes matter from a companion star and the resulting increase in its central pressure and temperature ignites thermonuclear explosion. Here we report observations with the Swift Space Telescope of strong but declining ultraviolet emission from a type Ia supernova within four days of its explosion. This emission is consistent with theoretical expectations of collision between material ejected by the supernova and a companion star, and therefore provides evidence that some type Ia supernovae arise from the single degenerate channel.

  2. THE RISE TIME OF NORMAL AND SUBLUMINOUS TYPE Ia SUPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Gaitan, S.; Perrett, K.; Carlberg, R. [Department of Astronomy and Astrophysics, University of Toronto, 50 St. george Street, Toronto, ON M5S 3H4 (Canada); Conley, A. [Center for Astrophysics and Space Astronomy, University of Colorado, 593 UCB, Boulder, CO 80309-0593 (United States); Bianco, F. B.; Howell, D. A.; Graham, M. L. [Department of Physics, University of California, Santa Barbara, Broida Hall, Mail Code 9530, Santa Barbara, CA 93106-9530 (United States); Sullivan, M.; Hook, I. M. [Department of Physics (Astrophysics), University of Oxford, DWB, Keble Road, Oxford, OX1 3RH (United Kingdom); Astier, P.; Balland, C.; Fourmanoit, N.; Guy, J.; Hardin, D.; Pain, R. [LPNHE, Universite Pierre et Marie Curie Paris 6, Universite Paris Diderot Paris 7, CNRS-IN2P3, 4 Place Jussieu, 75252 Paris Cedex 05 (France); Balam, D. [Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Basa, S. [Laboratoire d' Astrophysique de Marseille, Pole de l' Etoile Site de Chateau-Gombert, 38, rue Frederic Joliot-Curie, 13388 Marseille cedex 13 (France); Fouchez, D. [CPPM, CNRS-IN2P3 and University Aix Marseille II, Case 907, 13288 Marseille cedex 9 (France); Lidman, C. [Australian Astronomical Observatory, P.O. Box 296, Epping, NSW 1710 (Australia); Palanque-Delabrouille, N., E-mail: gonzalez@astro.utoronto.ca [DSM/IRFU/SPP, CEA-Saclay, F-91191 Gif-sur-Yvette (France); and others

    2012-01-20

    We calculate the average stretch-corrected rise time of Type Ia supernovae (SNe Ia) in the Supernova Legacy Survey. We use the aggregate light curves of spectroscopic and photometrically identified SNe Ia to fit the rising part of the light curve with a simple quadratic model. We obtain a light curve shape corrected, i.e., stretch-corrected, fiducial rise time of 17.02{sup +0.18}{sub -0.28} (stat) days. The measured rise time differs from an earlier finding by the SNLS (Conley et al.) due to the use of different SN Ia templates. We compare it to nearby samples using the same methods and find no evolution in the early part of the light curve of SNe Ia up to z = 1. We search for variations among different populations, particularly subluminous objects, by dividing the sample in stretch. Bright and slow decliners (s > 1.0) have consistent stretch-corrected rise times compared to fainter and faster decliners (0.8 < s {<=} 1.0); they are shorter by 0.57{sup +0.47}{sub -0.50} (stat) days. Subluminous SNe Ia (here defined as objects with s {<=} 0.8), although less constrained, are also consistent, with a rise time of 18.03{sup +0.81}{sub -1.37} (stat) days. We study several systematic biases and find that the use of different fiducial templates may affect the average rise time but not the intrinsic differences between populations. Based on our results, we estimate that subluminous SNe Ia are powered by 0.05-0.35 M{sub Sun} of {sup 56}Ni synthesized in the explosion. Our conclusions are the same for the single-stretch and two-stretch parameterizations of the light curve.

  3. IMPROVED DISTANCES TO TYPE Ia SUPERNOVAE WITH TWO SPECTROSCOPIC SUBCLASSES

    International Nuclear Information System (INIS)

    Wang, X.; Filippenko, A. V.; Ganeshalingam, M.; Li, W.; Silverman, J. M.; Chornock, R.; Foley, R. J.; Macomber, B.; Serduke, F. J. D.; Steele, T. N.; Wong, D. S.; Wang, L.; Gates, E. L.

    2009-01-01

    We study the observables of 158 relatively normal Type Ia supernovae (SNe Ia) by dividing them into two groups in terms of the expansion velocity inferred from the absorption minimum of the Si II λ6355 line in their spectra near B-band maximum brightness. One group ('Normal') consists of normal SNe Ia populating a narrow strip in the Si II velocity distribution, with an average expansion velocity (v) = 10, 600 ± 400 km s -1 near B maximum; the other group ('HV') consists of objects with higher velocities, v ∼> 11, 800 km s -1 . Compared with the Normal group, the HV one shows a narrower distribution in both the peak luminosity and the luminosity decline rate Δm 15 . In particular, their B-V colors at maximum brightness are found to be on average redder by ∼ 0.1 mag, suggesting that they either are associated with dusty environments or have intrinsically red B-V colors. The HV SNe Ia are also found to prefer a lower extinction ratio R V ∼ 1.6 (versus ∼ 2.4 for the Normal ones). Applying such an absorption-correction dichotomy to SNe Ia of these two groups remarkably reduces the dispersion in their peak luminosity from 0.178 mag to only 0.125 mag.

  4. VELOCITY EVOLUTION AND THE INTRINSIC COLOR OF TYPE Ia SUPERNOVAE

    International Nuclear Information System (INIS)

    Foley, Ryan J.; Sanders, Nathan E.; Kirshner, Robert P.

    2011-01-01

    To understand how best to use observations of Type Ia supernovae (SNe Ia) to obtain precise and accurate distances, we investigate the relations between spectra of SNe Ia and their intrinsic colors. Using a sample of 1630 optical spectra of 255 SNe, based primarily on data from the CfA Supernova Program, we examine how the velocity evolution and line strengths of Si II λ6355 and Ca II H and K are related to the B – V color at peak brightness. We find that the maximum-light velocity of Si II λ6355 and Ca II H and K and the maximum-light pseudo-equivalent width of Si II λ6355 are correlated with intrinsic color, with intrinsic color having a linear relation with the Si II λ6355 measurements. Ca II H and K does not have a linear relation with intrinsic color, but lower-velocity SNe tend to be intrinsically bluer. Combining the spectroscopic measurements does not improve intrinsic color inference. The intrinsic color scatter is larger for higher-velocity SNe Ia—even after removing a linear trend with velocity—indicating that lower-velocity SNe Ia are more 'standard crayons'. Employing information derived from SN Ia spectra has the potential to improve the measurements of extragalactic distances and the cosmological properties inferred from them.

  5. The interaction of Type Ia supernovae with their circumstellar medium

    NARCIS (Netherlands)

    Chiotellis, A.

    2013-01-01

    This thesis is focused on the study of a specific class of supernovae, named Type Ia (or thermonuclear) supernovae. In particular, we attempt to gain information about their origin through the study of the interaction of these supernovae with circumstellar structures that have been shaped by their

  6. Introduction review on cosmology with Type Ia supernovae

    OpenAIRE

    Guy, Julien

    2008-01-01

    In this short review, some key aspects of the cosmology with type Ia supernovae are discussed in light of the recent results of high redshift surveys. The interpretation of SNe colours, the impact of calibration and the recent developments in the tests for an evolution of the population with redshift are addressed.

  7. Cosmic Supernova Rate History and Type Ia Supernova Progenitors

    OpenAIRE

    Kobayashi, Chiaki; Nomoto, Ken'ichi; Tsujimoto, Takuji

    2001-01-01

    Adopting a single degenerate scenario for Type Ia supernova progenitors with the metallicity effect, we make a prediction of the cosmic supernova rate history as a composite of the supernova rates in spiral and elliptical galaxies, and compare with the recent observational data up to z ~ 0.55.

  8. Type Ia supernovae yielding distances with 3-4% precision

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Patrick L. [Univ. of California, Berkeley, CA (United States); Filippenko, Alexei V. [Univ. of California, Berkeley, CA (United States); Burke, David L. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Hicken, Malcolm [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States); Ganeshalingam, Mohan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Zheng, Weikang [Univ. of California, Berkeley, CA (United States)

    2015-01-26

    The luminosities of Type Ia supernovae (SN), the thermonuclear explosions of white dwarf stars, vary systematically with their intrinsic color and light-curve decline rate. These relationships have been used to calibrate their luminosities to within ~0.14–0.20 mag from broadband optical light curves, yielding individual distances accurate to ~7–10%. Here we identify a subset of SN Ia that erupt in environments having high ultraviolet surface brightness and star-formation surface density. When we apply a steep model extinction law, these SN can be calibrated to within ~0.065–0.075 mag, corresponding to ~3–4% in distance — the best yet with SN Ia by a substantial margin. The small scatter suggests that variations in only one or two progenitor properties account for their light-curve-width/color/luminosity relation.

  9. Critical ingredients of Type Ia supernova radiative-transfer modelling

    Science.gov (United States)

    Dessart, Luc; Hillier, D. John; Blondin, Stéphane; Khokhlov, Alexei

    2014-07-01

    We explore the physics of Type Ia supernova (SN Ia) light curves and spectra using the 1D non-local thermodynamic equilibrium (non-LTE) time-dependent radiative-transfer code CMFGEN. Rather than adjusting ejecta properties to match observations, we select as input one `standard' 1D Chandrasekhar-mass delayed-detonation hydrodynamical model, and then explore the sensitivity of radiation and gas properties of the ejecta on radiative-transfer modelling assumptions. The correct computation of SN Ia radiation is not exclusively a solution to an `opacity problem', characterized by the treatment of a large number of lines. We demonstrate that the key is to identify and treat important atomic processes consistently. This is not limited to treating line blanketing in non-LTE. We show that including forbidden-line transitions of metals, and in particular Co, is increasingly important for the temperature and ionization of the gas beyond maximum light. Non-thermal ionization and excitation are also critical since they affect the colour evolution and the ΔM15 decline rate of our model. While impacting little the bolometric luminosity, a more complete treatment of decay routes leads to enhanced line blanketing, e.g. associated with 48Ti in the U and B bands. Overall, we find that SN Ia radiation properties are influenced in a complicated way by the atomic data we employ, so that obtaining converged results is a real challenge. Nonetheless, with our fully fledged CMFGEN model, we obtain good agreement with the golden standard Type Ia SN 2005cf in the optical and near-IR, from 5 to 60 d after explosion, suggesting that assuming spherical symmetry is not detrimental to SN Ia radiative-transfer modelling at these times. Multi-D effects no doubt matter, but they are perhaps less important than accurately treating the non-LTE processes that are crucial to obtain reliable temperature and ionization structures.

  10. Near-infrared absolute magnitudes of Type Ia Supernovae

    Science.gov (United States)

    Avelino, Arturo; Friedman, Andrew S.; Mandel, Kaisey; Kirshner, Robert; Challis, Peter

    2017-01-01

    Type Ia Supernovae light curves (SN Ia) in the near infrared (NIR) exhibit low dispersion in their peak luminosities and are less vulnerable to extinction by interstellar dust in their host galaxies. The increasing number of high quality NIR SNe Ia light curves, including the recent CfAIR2 sample obtained with PAIRITEL, provides updated evidence for their utility as standard candles for cosmology. Using NIR YJHKs light curves of ~150 nearby SNe Ia from the CfAIR2 and CSP samples, and from the literature, we determine the mean value and dispersion of the absolute magnitude in the range between -10 to 50 rest-frame days after the maximum luminosity in B band. We present the mean light-curve templates and Hubble diagram for YJHKs bands. This work contributes to a firm local anchor for supernova cosmology studies in the NIR which will help to reduce the systematic uncertainties due to host galaxy dust present in optical-only studies. This research is supported by NSF grants AST-156854, AST-1211196, Fundacion Mexico en Harvard, and CONACyT.

  11. Type Ia supernovae as speed sensors at intermediate redshifts

    International Nuclear Information System (INIS)

    Zhang Pengjie; Chen Xuelei

    2008-01-01

    Large scale peculiar velocity (LSPV) is a crucial probe of dark matter, dark energy, and gravity at cosmological scales. However, its application is severely limited by measurement obstacles. We show that fluctuations in type Ia supernovae fluxes induced by LSPV offer a promising approach to measure LSPV at intermediate redshifts. In the 3D Fourier space, gravitational lensing, the dominant systematical error, is well suppressed, localized, and can be further corrected effectively. Advances in supernova observations can further significantly reduce shot noise induced by supernova intrinsic fluctuations, which is the dominant statistical error. Robust mapping on the motion of the dark universe through type Ia supernovae is thus feasible to z∼0.5.

  12. Three-dimensional Modeling of Type Ia Supernova Explosions

    Science.gov (United States)

    Khokhlov, Alexei

    2001-06-01

    A deflagration explosion of a Type Ia Supernova (SNIa) is studied using three-dimensional, high-resolution, adaptive mesh refinement fluid dynamic calculations. Deflagration speed in an exploding Chandrasekhar-mass carbon-oxygen white dwarf (WD) grows exponentially, reaches approximately 30the speed of sound, and then declines due to a WD expansion. Outermost layers of the WD remain unburned. The explosion energy is comparable to that of a Type Ia supernova. The freezing of turbulent motions by expansion appears to be a crucial physical mechanism regulating the strength of a supernova explosion. In contrast to one-dimensional models, three-dimensional calculations predict the formation of Si-group elements and pockets of unburned CO in the middle and in central regions of a supernova ejecta. This, and the presence of unburned outer layer of carbon-oxygen may pose problems for SNIa spectra. Explosion sensitivity to initial conditions and its relation to a diversity of SNIa is discussed.

  13. Marginal evidence for cosmic acceleration from Type Ia supernovae

    OpenAIRE

    Nielsen, Jeppe Trøst; Guffanti, Alberto; Sarkar, Subir

    2016-01-01

    The "standard" model of cosmology is founded on the basis that the expansion rate of the universe is accelerating at present --- as was inferred originally from the Hubble diagram of Type Ia supernovae. There exists now a much bigger database of supernovae so we can perform rigorous statistical tests to check whether these "standardisable candles" indeed indicate cosmic acceleration. Taking account of the empirical procedure by which corrections are made to their absolute magnitudes to allow ...

  14. The physics of flames in Type Ia supernovae

    International Nuclear Information System (INIS)

    Zingale, M; Woosley, S E; Bell, J B; Day, M S; Rendleman, C A

    2005-01-01

    We extend a low Mach number hydrodynamics method developed for terrestrial combustion, to the study of thermonuclear flames in Type Ia supernovae. We discuss the differences between 2-D and 3-D Rayleigh-Taylor unstable flame simulations, and give detailed diagnostics on the turbulence, showing that the kinetic energy power spectrum obeys Bolgiano-Obukhov statistics in 2-D, but Kolmogorov statistics in 3-D. Preliminary results from 3-D reacting bubble calculations are shown, and their implications for ignition are discussed

  15. iPTF Discoveries of Recent Type Ia Supernovae

    Science.gov (United States)

    Papadogiannakis, S.; Taddia, F.; Petrushevska, T.; Ferretti, R.; Fremling, C.; Karamehmetoglu, E.; Nyholm, A.; Roy, R.; Hangard, L.; Vreeswijk, P.; Horesh, A.; Manulis, I.; Rubin, A.; Yaron, O.; Leloudas, G.; Khazov, D.; Soumagnac, M.; Knezevic, S.; Johansson, J.; Nir, G.; Cao, Y.; Blagorodnova, N.; Kulkarni, S.

    2016-05-01

    The intermediate Palomar Transient Factory (ATel #4807) reports the discovery and classification of the following Type Ia SNe. Our automated candidate vetting to distinguish a real astrophysical source (1.0) from bogus artefacts (0.0) is powered by three generations of machine learning algorithms: RB2 (Brink et al. 2013MNRAS.435.1047B), RB4 (Rebbapragada et al. 2015AAS...22543402R) and RB5 (Wozniak et al. 2013AAS...22143105W).

  16. IMPROVING COSMOLOGICAL DISTANCE MEASUREMENTS USING TWIN TYPE IA SUPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Fakhouri, H. K.; Boone, K.; Aldering, G.; Aragon, C.; Bailey, S.; Fagrelius, P. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Fleury, M. [Laboratoire de Physique Nucléaire et des Hautes Énergies, Université Pierre et Marie Curie Paris 6, Université Paris Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Barbary, K. [Department of Physics, University of California Berkeley, 366 LeConte Hall MC 7300, Berkeley, CA 94720-7300 (United States); Baugh, D.; Chen, J. [Tsinghua Center for Astrophysics, Tsinghua University, Beijing 100084 (China); Buton, C.; Chotard, N.; Copin, Y. [Université de Lyon 1, Villeurbanne (France); CNRS/IN2P3, Institut de Physique Nucléaire de Lyon, F-69622, Lyon (France); Childress, M. [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Feindt, U. [Institut fur Physik, Humboldt-Universitat zu Berlin, Newtonstrasse 15, D-12489 Berlin (Germany); Fouchez, D. [Centre de Physique des Particules de Marseille, Aix-Marseille Université, CNRS/IN2P3, 163 avenue de Luminy—Case 902—F-13288 Marseille Cedex 09 (France); Gangler, E. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, Laboratoire de Physique Corpusculaire, BP 10448, F-63000 Clermont-Ferrand (France); Collaboration: Nearby Supernova Factory; and others

    2015-12-10

    We introduce a method for identifying “twin” Type Ia supernovae (SNe Ia) and using them to improve distance measurements. This novel approach to SN Ia standardization is made possible by spectrophotometric time series observations from the Nearby Supernova Factory (SNfactory). We begin with a well-measured set of SNe, find pairs whose spectra match well across the entire optical window, and then test whether this leads to a smaller dispersion in their absolute brightnesses. This analysis is completed in a blinded fashion, ensuring that decisions made in implementing the method do not inadvertently bias the result. We find that pairs of SNe with more closely matched spectra indeed have reduced brightness dispersion. We are able to standardize this initial set of SNfactory SNe to 0.083 ± 0.012 mag, implying a dispersion of 0.072 ± 0.010 mag in the absence of peculiar velocities. We estimate that with larger numbers of comparison SNe, e.g., using the final SNfactory spectrophotometric data set as a reference, this method will be capable of standardizing high-redshift SNe to within 0.06–0.07 mag. These results imply that at least 3/4 of the variance in Hubble residuals in current SN cosmology analyses is due to previously unaccounted-for astrophysical differences among the SNe.

  17. THE ABSOLUTE MAGNITUDES OF TYPE Ia SUPERNOVAE IN THE ULTRAVIOLET

    International Nuclear Information System (INIS)

    Brown, Peter J.; Roming, Peter W. A.; Ciardullo, Robin; Gronwall, Caryl; Hoversten, Erik A.; Pritchard, Tyler; Milne, Peter; Bufano, Filomena; Mazzali, Paolo; Elias-Rosa, Nancy; Filippenko, Alexei V.; Li Weidong; Foley, Ryan J.; Hicken, Malcolm; Kirshner, Robert P.; Gehrels, Neil; Holland, Stephen T.; Immler, Stefan; Phillips, Mark M.; Still, Martin

    2010-01-01

    We examine the absolute magnitudes and light-curve shapes of 14 nearby (redshift z = 0.004-0.027) Type Ia supernovae (SNe Ia) observed in the ultraviolet (UV) with the Swift Ultraviolet/Optical Telescope. Colors and absolute magnitudes are calculated using both a standard Milky Way extinction law and one for the Large Magellanic Cloud that has been modified by circumstellar scattering. We find very different behavior in the near-UV filters (uvw1 rc covering ∼2600-3300 A after removing optical light, and u ∼ 3000-4000 A) compared to a mid-UV filter (uvm2 ∼2000-2400 A). The uvw1 rc - b colors show a scatter of ∼0.3 mag while uvm2-b scatters by nearly 0.9 mag. Similarly, while the scatter in colors between neighboring filters is small in the optical and somewhat larger in the near-UV, the large scatter in the uvm2 - uvw1 colors implies significantly larger spectral variability below 2600 A. We find that in the near-UV the absolute magnitudes at peak brightness of normal SNe Ia in our sample are correlated with the optical decay rate with a scatter of 0.4 mag, comparable to that found for the optical in our sample. However, in the mid-UV the scatter is larger, ∼1 mag, possibly indicating differences in metallicity. We find no strong correlation between either the UV light-curve shapes or the UV colors and the UV absolute magnitudes. With larger samples, the UV luminosity might be useful as an additional constraint to help determine distance, extinction, and metallicity in order to improve the utility of SNe Ia as standardized candles.

  18. Necrotic foci, elevated chemokines and infiltrating neutrophils in the liver of glycogen storage disease type Ia

    Science.gov (United States)

    Kim, So Youn; Weinstein, David A.; Starost, Matthew F.; Mansfield, Brian C.; Chou, Janice Y.

    2009-01-01

    Background/Aims Glycogen storage disease type Ia (GSD-Ia) patients manifest the long-term complication of hepatocellular adenoma (HCA) of unknown etiology. We showed previously that GSD-Ia mice exhibit neutrophilia and elevated serum cytokine levels. This study was conducted to evaluate whether human GSD-Ia patients exhibit analogous increases and whether in GSD-Ia mice a correlation exists between immune abnormalities and, biochemical and histological alterations in the liver. Methods Differential leukocyte counts and cytokine levels were investigated in GSD-Ia patients. Hepatic chemokine production, neutrophil infiltration, and histological abnormalities were investigated in GSD-Ia mice. Results We show that GSD-Ia patients exhibit increased peripheral neutrophil counts and serum interleukin-8 (IL-8). Compared to normal subjects, HCA-bearing GSD-Ia patients have a 2.8-fold higher serum IL8 concentration, while GSD-Ia patients without HCA have a 1.4-fold higher concentration. Hepatic injury in GSD-Ia mice is evidenced by necrotic foci, markedly elevated infiltrating neutrophils, and increased hepatic production of chemokines. Conclusion Peripheral neutrophilia and elevated serum chemokines are characteristic of GSD-Ia with HCA-bearing GSD-Ia patients having the highest serum IL-8. In GSD-Ia mice these elevations correlate with elevated hepatic chemokine levels, neutrophil infiltration, and necrosis. Taken together, peripheral neutrophilia and increased serum chemokines may indicate hepatic injuries in GSD-Ia PMID:18191274

  19. Tension in the recent Type Ia supernovae datasets

    International Nuclear Information System (INIS)

    Wei, Hao

    2010-01-01

    In the present work, we investigate the tension in the recent Type Ia supernovae (SNIa) datasets Constitution and Union. We show that they are in tension not only with the observations of the cosmic microwave background (CMB) anisotropy and the baryon acoustic oscillations (BAO), but also with other SNIa datasets such as Davis and SNLS. Then, we find the main sources responsible for the tension. Further, we make this more robust by employing the method of random truncation. Based on the results of this work, we suggest two truncated versions of the Union and Constitution datasets, namely the UnionT and ConstitutionT SNIa samples, whose behaviors are more regular.

  20. Marginal evidence for cosmic acceleration from Type Ia supernovae.

    Science.gov (United States)

    Nielsen, J T; Guffanti, A; Sarkar, S

    2016-10-21

    The 'standard' model of cosmology is founded on the basis that the expansion rate of the universe is accelerating at present - as was inferred originally from the Hubble diagram of Type Ia supernovae. There exists now a much bigger database of supernovae so we can perform rigorous statistical tests to check whether these 'standardisable candles' indeed indicate cosmic acceleration. Taking account of the empirical procedure by which corrections are made to their absolute magnitudes to allow for the varying shape of the light curve and extinction by dust, we find, rather surprisingly, that the data are still quite consistent with a constant rate of expansion.

  1. A novel mutation in a case of pseudohypoparathyroidism type Ia.

    Science.gov (United States)

    Kırel, Birgül; Demiral, Meliha; Bozdağ, Özkan; Karaer, Kadri

    2016-01-01

    Pseudohypoparathyroidism (PHP) type Ia is characterized by multiple hormone resistance; primarily parathyroid hormone (PTH) resistance and Albright's hereditary osteodystrophy (AHO) which involves skeletal and developmental defects. The AHO phenotype alone without hormone resistance is defined as pseudoPHP. A boy was first diagnosed as having both rickets and primary hypothyroidism at 2.5 months of age. His calcium level remained within normal levels after vitamin D treatment, but, elevated PTH and ALP levels and normal-high phosphate levels persisted during his follow-up by age of 2.5 years. He was admitted with hypocalcemic convulsions as well as hyperphosphatemia and elevated PTH levels suggested PTH resistance at 2.5 years of age. He and his mother were obese and had round faces, frontal bossing, small noses, flat nasal bridges, brachydactyly. His mother showed no hormonal resistance. These findings indicated that our patient had PHP type Ia and his mother had pseudoPHP. The same novel heterozygous mutation in the GNAS gene (IVS4+5G > C) was identified in both of patients.

  2. THE SUBLUMINOUS AND PECULIAR TYPE Ia SUPERNOVA PTF 09dav

    International Nuclear Information System (INIS)

    Sullivan, M.; Ofek, E. O.; Blake, S.; Podsiadlowski, P.; Kasliwal, M. M.; Cooke, J.; Quimby, R.; Kulkarni, S. R.; Nugent, P. E.; Thomas, R. C.; Poznanski, D.; Howell, D. A.; Arcavi, I.; Gal-Yam, A.; Hook, I. M.; Mazzali, P.; Bildsten, L.; Bloom, J. S.; Cenko, S. B.; Law, N.

    2011-01-01

    PTF 09dav is a peculiar subluminous Type Ia supernova (SN) discovered by the Palomar Transient Factory (PTF). Spectroscopically, it appears superficially similar to the class of subluminous SN1991bg-like SNe, but it has several unusual features which make it stand out from this population. Its peak luminosity is fainter than any previously discovered SN1991bg-like SN Ia (M B ∼ -15.5), but without the unusually red optical colors expected if the faint luminosity were due to extinction. The photospheric optical spectra have very unusual strong lines of Sc II and Mg I, with possible Sr II, together with stronger than average Ti II and low velocities of ∼6000 km s -1 . The host galaxy of PTF09dav is ambiguous. The SN lies either on the extreme outskirts (∼41 kpc) of a spiral galaxy or in an very faint (M R ≥ -12.8) dwarf galaxy, unlike other 1991bg-like SNe which are invariably associated with massive, old stellar populations. PTF 09dav is also an outlier on the light-curve-width-luminosity and color-luminosity relations derived for other subluminous SNe Ia. The inferred 56 Ni mass is small (0.019 ± 0.003 M sun ), as is the estimated ejecta mass of 0.36 M sun . Taken together, these properties make PTF 09dav a remarkable event. We discuss various physical models that could explain PTF 09dav. Helium shell detonation or deflagration on the surface of a CO white dwarf can explain some of the features of PTF 09dav, including the presence of Sc and the low photospheric velocities, but the observed Si and Mg are not predicted to be very abundant in these models. We conclude that no single model is currently capable of explaining all of the observed signatures of PTF 09dav.

  3. Spectral Sequences of Type Ia Supernovae. I. Connecting Normal and Subluminous SNe Ia and the Presence of Unburned Carbon

    Energy Technology Data Exchange (ETDEWEB)

    Heringer, E.; Kerkwijk, M. H. van [Department of Astronomy and Astrophysics, University of Toronto, 50 Saint George Street, Toronto, ON M5S 3H4 (Canada); Sim, S. A. [Astrophysics Research Centre, School of Mathematics and Physics, Queens University Belfast, Belfast BT7 1NN (United Kingdom); Kerzendorf, W. E. [European Southern Observatory (ESO), Karl-Schwarzschild-Straße 2, D-85748 Garching (Germany)

    2017-09-01

    Type Ia supernovae (SNe Ia) are generally agreed to arise from thermonuclear explosions of carbon–oxygen white dwarfs. The actual path to explosion, however, remains elusive, with numerous plausible parent systems and explosion mechanisms suggested. Observationally, SNe Ia have multiple subclasses, distinguished by their light curves and spectra. This raises the question of whether these indicate that multiple mechanisms occur in nature or that explosions have a large but continuous range of physical properties. We revisit the idea that normal and 91bg-like SNe can be understood as part of a spectral sequence in which changes in temperature dominate. Specifically, we find that a single ejecta structure is sufficient to provide reasonable fits of both the normal SN Ia SN 2011fe and the 91bg-like SN 2005bl, provided that the luminosity and thus temperature of the ejecta are adjusted appropriately. This suggests that the outer layers of the ejecta are similar, thus providing some support for a common explosion mechanism. Our spectral sequence also helps to shed light on the conditions under which carbon can be detected in premaximum SN Ia spectra—we find that emission from iron can “fill in” the carbon trough in cool SNe Ia. This may indicate that the outer layers of the ejecta of events in which carbon is detected are relatively metal-poor compared to events in which carbon is not detected.

  4. Detection of the gravitational lens magnifying a type Ia supernova.

    Science.gov (United States)

    Quimby, Robert M; Oguri, Masamune; More, Anupreeta; More, Surhud; Moriya, Takashi J; Werner, Marcus C; Tanaka, Masayuki; Folatelli, Gaston; Bersten, Melina C; Maeda, Keiichi; Nomoto, Ken'ichi

    2014-04-25

    Objects of known brightness, like type Ia supernovae (SNIa), can be used to measure distances. If a massive object warps spacetime to form multiple images of a background SNIa, a direct test of cosmic expansion is also possible. However, these lensing events must first be distinguished from other rare phenomena. Recently, a supernova was found to shine much brighter than normal for its distance, which resulted in a debate: Was it a new type of superluminous supernova or a normal SNIa magnified by a hidden gravitational lens? Here, we report that a spectrum obtained after the supernova faded away shows the presence of a foreground galaxy-the first found to strongly magnify a SNIa. We discuss how more lensed SNIa can be found than previously predicted.

  5. Measuring weak lensing correlations of Type Ia supernovae

    Science.gov (United States)

    Scovacricchi, D.; Nichol, R. C.; Macaulay, E.; Bacon, D.

    2017-03-01

    We study the feasibility of detecting weak lensing spatial correlations between supernova (SN) Type Ia magnitudes with present (Dark Energy Survey, DES) and future (Large Synoptic Survey Telescope, LSST) surveys. We investigate the angular auto-correlation function of SN magnitudes (once the background cosmology has been subtracted) and cross-correlation with galaxy catalogues. We examine both analytical and numerical predictions, the latter using simulated galaxy catalogues from the MICE Grand Challenge Simulation. We predict that we will be unable to detect the SN auto-correlation in DES, while it should be detectable with the LSST SN deep fields (15 000 SNe on 70 deg2) at ≃6σ level of confidence (assuming 0.15 mag of intrinsic dispersion). The SN-galaxy cross-correlation function will deliver much higher signal to noise, being detectable in both surveys with an integrated signal to noise of ∼100 (up to 30 arcmin separations). We predict joint constraints on the matter density parameter (Ωm) and the clustering amplitude (σ8) by fitting the auto-correlation function of our mock LSST deep fields. When assuming a Gaussian prior for Ωm, we can achieve a 25 per cent measurement of σ8 from just these LSST supernovae (assuming 0.15 mag of intrinsic dispersion). These constraints will improve significantly if the intrinsic dispersion of SNe Ia can be reduced.

  6. Theory of Nova Outbursts and Type Ia Supernovae

    Directory of Open Access Journals (Sweden)

    M. Kato

    2015-02-01

    Full Text Available We briefly review the current theoretical understanding of the light curves of novae. These curves exhibit a homologous nature, dubbed the universal decline law, and when time-normalized, they almost follow a single curve independently of the white dwarf (WD mass or chemical composition of the envelope. The optical and near-infrared light curves of novae are reproduced mainly by free-free emission from their optically thick winds. We can estimate the WD mass from multiwavelength observations because the optical, UV, and soft X-ray light curves evolve differently and we can easily resolve the degeneracy of the optical light curves. Recurrent novae and classical novae are a testbed of type Ia supernova scenarios. In the orbital period versus secondary mass diagram, recurrent novae are located in different regions from classical novae and the positions of recurrent novae are consistent with the single degenerate scenario.

  7. Photometry of High-Redshift Gravitationally Lensed Type Ia Supernovae

    Science.gov (United States)

    Haynie, Annastasia

    2018-01-01

    Out of more than 1100 well-identified Type Ia Supernovae, only roughly 10 of them are at z> 1.5. High redshift supernovae are hard to detect but this is made easier by taking advantage of the effects of gravitational lensing, which magnifies objects in the background field of massive galaxy clusters. Supernova Nebra (z= ~1.8), among others, was discovered during observations taken as part of the RELICS survey, which focused on fields of view that experience strong gravitational lensing effects. SN Nebra, which sits behind galaxy cluster Abell 1763, is magnified and therefore appears closer and easier to see than with HST alone. Studying high-redshift supernovae like SN Nebra is an important step towards creating cosmological models that accurately describe the behavior of dark energy in the early Universe. Recent efforts have been focused on improving photometry and the building and fitting of preliminary light curves.

  8. Type Ia Supernova Hubble Residuals and Host-Galaxy Properties

    Energy Technology Data Exchange (ETDEWEB)

    Nearby Supernova Factory; Kim, A. G.; Aldering, G.; Antilogus, P.; Aragon, C.; Bailey, S.; Baltay, C.; Bongard, S.; Buton, C.; Canto, A.; Cellier-Holzem, F.; Childress, M.; Chotard, N.; Copin, Y.; Fakhouri, H. K.; Feindt, U.; Fleury, M.; Gangler, E.; Greskovic, P.; Guy, J.; Kowalski, M.; Lombardo, S.; Nordin, J.; Nugent, P.; Pain, R.; Pecontal, E.; Pereira, R.; Perlmutter, S.; Rabinowitz, D.; Rigault, M.; Runge, K.; Saunders, C.; Scalzo, R.; Smadja, G.; Tao, C.; Thomas, R. C.; Weaver, B. A.

    2014-01-17

    Kim et al. (2013) [K13] introduced a new methodology for determining peak- brightness absolute magnitudes of type Ia supernovae from multi-band light curves. We examine the relation between their parameterization of light curves and Hubble residuals, based on photometry synthesized from the Nearby Supernova Factory spec- trophotometric time series, with global host-galaxy properties. The K13 Hubble residual step with host mass is 0.013 ? 0.031 mag for a supernova subsample with data coverage corresponding to the K13 training; at ? 1?, the step is not significant and lower than previous measurements. Relaxing the data coverage requirement the Hubble residual step with host mass is 0.045 ? 0.026 mag for the larger sample; a calculation using the modes of the distributions, less sensitive to outliers, yields a step of 0.019 mag. The analysis of this article uses K13 inferred luminosities, as distinguished from previous works that use magnitude corrections as a function of SALT2 color and stretch param- eters: Steps at> 2? significance are found in SALT2 Hubble residuals in samples split by the values of their K13 x(1) and x(2) light-curve parameters. x(1) affects the light- curve width and color around peak (similar to the∆m15 and stretch parameters), and x(2) affects colors, the near-UV light-curve width, and the light-curve decline 20 to 30 days after peak brightness. The novel light-curve analysis, increased parameter set, and magnitude corrections of K13 may be capturing features of SN Ia diversity arising from progenitor stellar evolution.

  9. Type Ia supernova Hubble residuals and host-galaxy properties

    Energy Technology Data Exchange (ETDEWEB)

    Kim, A. G.; Aldering, G.; Aragon, C.; Bailey, S.; Fakhouri, H. K. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Fleury, M.; Guy, J. [Laboratoire de Physique Nucléaire et des Hautes Énergies, Université Pierre et Marie Curie Paris 6, Université Paris Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Feindt, U.; Greskovic, P.; Kowalski, M. [Physikalisches Institut, Universität Bonn, Nußallee 12, D-53115 Bonn (Germany); Childress, M. [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Chotard, N.; Copin, Y.; Gangler, E. [Université de Lyon, F-69622 Lyon (France); Université de Lyon 1, Villeurbanne (France); CNRS/IN2P3, Institut de Physique Nucléaire de Lyon (France); and others

    2014-03-20

    Kim et al. introduced a new methodology for determining peak-brightness absolute magnitudes of type Ia supernovae from multi-band light curves. We examine the relation between their parameterization of light curves and Hubble residuals, based on photometry synthesized from the Nearby Supernova Factory spectrophotometric time series, with global host-galaxy properties. The K13 Hubble residual step with host mass is 0.013 ± 0.031 mag for a supernova subsample with data coverage corresponding to the K13 training; at <<1σ, the step is not significant and lower than previous measurements. Relaxing the data coverage requirement of the Hubble residual step with the host mass is 0.045 ± 0.026 mag for the larger sample; a calculation using the modes of the distributions, less sensitive to outliers, yields a step of 0.019 mag. The analysis of this article uses K13 inferred luminosities, as distinguished from previous works that use magnitude corrections as a function of SALT2 color and stretch parameters: steps at >2σ significance are found in SALT2 Hubble residuals in samples split by the values of their K13 x(1) and x(2) light-curve parameters. x(1) affects the light-curve width and color around peak (similar to the Δm {sub 15} and stretch parameters), and x(2) affects colors, the near-UV light-curve width, and the light-curve decline 20-30 days after peak brightness. The novel light-curve analysis, increased parameter set, and magnitude corrections of K13 may be capturing features of SN Ia diversity arising from progenitor stellar evolution.

  10. ON THE RATES OF TYPE Ia SUPERNOVAE IN DWARF AND GIANT HOSTS WITH ROTSE-IIIb

    Energy Technology Data Exchange (ETDEWEB)

    Quimby, Robert M. [Kavli IPMU, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba 277-8583 (Japan); Yuan Fang [Research School of Astronomy and Astrophysics, Australian National University, Weston Creek, ACT 2611 (Australia); Akerlof, Carl [Physics Department, University of Michigan, Ann Arbor, MI 48109 (United States); Wheeler, J. Craig [Department of Astronomy, McDonald Observatory, University of Texas, Austin, TX 78712 (United States); Warren, Michael S. [Theoretical Division, Mail Stop B227, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2012-12-01

    We present a sample of 23 spectroscopically confirmed Type Ia supernovae (SNe Ia) that were discovered in the background of galaxy clusters targeted by ROTSE-IIIb and use up to 18 of these to determine the local (z-bar 0.05) volumetric rate. Since our survey is flux limited and thus biased against fainter objects, the pseudo-absolute magnitude distribution (pAMD) of SNe Ia in a given volume is an important concern, especially the relative frequency of high- to low-luminosity SNe Ia. We find that the pAMD derived from the volume-limited Lick Observatory Supernova Search (LOSS) sample is incompatible with the distribution of SNe Ia in a volume-limited (z < 0.12) sub-sample of the Sloan Digital Sky Survey II (SDSS-II). The LOSS sample requires far more low-luminosity SNe Ia than the SDSS-II can accommodate. Even though LOSS and SDSS-II have sampled different SNe Ia populations, their volumetric rates are surprisingly similar. Using the same model pAMD adopted in the SDSS-II SNe Ia rate calculation and excluding two high-luminosity SNe Ia from our sample, we derive a rate that is marginally higher than previous low-redshift determinations. With our full sample and the LOSS pAMD, our rate is more than double the canonical value. We also find that 5 of our 18 SNe Ia are hosted by very low luminosity (M{sub B} > -16) galaxies, whereas only 1 out of 79 nearby SDSS-II SNe Ia have such faint hosts. It is possible that previous works have undercounted either low-luminosity SNe Ia, SNe Ia in low-luminosity hosts, or peculiar SNe Ia (sometimes explicitly), and the total SNe Ia rate may be higher than the canonical value.

  11. Are the models for type Ia supernova progenitors consistent with the properties of supernova remnants?,

    NARCIS (Netherlands)

    Badenes, C.; Hughes, J.P.; Bravo, E.; Langer, N.

    2007-01-01

    We explore the relationship between the models for progenitor systems of Type Ia supernovae and the properties of the supernova remnants that evolve after the explosion. Most models for Type Ia progenitors in the single-degenerate scenario predict substantial outflows during the presupernova

  12. "Type Ia Supernovae: Tools for Studying Dark Energy" Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Woosley, Stan [Lick Observatory, San Jose, CA (United States); Kasen, Dan [Univ. of California, Berkeley, CA (United States)

    2017-05-10

    Final technical report for project "Type Ia Supernovae: Tools for the Study of Dark Energy" awarded jointly to scientists at the University of California, Santa Cruz and Berkeley, for computer modeling, theory and data analysis relevant to the use of Type Ia supernovae as standard candles for cosmology.

  13. Quantitative comparison between Type Ia supernova spectra at low and high redshifts: A case study

    Energy Technology Data Exchange (ETDEWEB)

    Supernova Cosmology Project; Nugent, Peter E; Garavini, G.; Folatelli, G.; Nobili, S.; Aldering, G.; Amanullah, R.; Antilogus, P.; Astier, P.; Blanc, G.; Bronder, J.; Burns, M.S.; Conley, A.; Deustua, S. E.; Doi, M.; Fabbro, S.; Fadeyev, V.; Gibbons, R.; Goldhaber, G.; Goobar, A.; Groom, D. E.; Hook, I.; Howell, D. A.; Kashikawa, N.; Kim, A. G.; Kowalski, M.; Kuznetsova, N.; Lee, B. C.; Lidman, C.; Mendez, J.; Morokuma, T.; Motohara, K.; Nugent, P. E.; Pain, R.; Perlmutter, S.; Quimby, R.; Raux, J.; Regnault, N.; Ruiz-Lapuente, P.; Sainton, G.; Schahmaneche, K.; Smith, E.; Spadafora, A. L.; Stanishev, V.; Thomas, R. C.; Walton, N. A.; Wang, L.; Wood-Vasey, W. M.; Yasuda, N.

    2008-03-24

    We develop a method to measure the strength of the absorption features in type Ia supernova (SN Ia) spectra and use it to make a quantitative comparisons between the spectra of type Ia supernovae at low and high redshifts. In this case study, we apply the method to 12 high-redshift (0.212 = z = 0.912) SNe Ia observed by the Supernova Cosmology Project. Through measurements of the strengths of these features and of the blueshift of theabsorption minimum in Ca ii H&K, we show that the spectra of the high-redshift SNe Ia are quantitatively similar to spectra of nearby SNe Ia (z< 0.15). One supernova in our high redshift sample, SN 2002fd at z = 0.279, is found to have spectral characteristics that are associated with peculiar SN 1991T/SN 1999aa-like supernovae.

  14. Early light curves for Type Ia supernova explosion models

    Science.gov (United States)

    Noebauer, U. M.; Kromer, M.; Taubenberger, S.; Baklanov, P.; Blinnikov, S.; Sorokina, E.; Hillebrandt, W.

    2017-12-01

    Upcoming high-cadence transient survey programmes will produce a wealth of observational data for Type Ia supernovae. These data sets will contain numerous events detected very early in their evolution, shortly after explosion. Here, we present synthetic light curves, calculated with the radiation hydrodynamical approach STELLA for a number of different explosion models, specifically focusing on these first few days after explosion. We show that overall the early light curve evolution is similar for most of the investigated models. Characteristic imprints are induced by radioactive material located close to the surface. However, these are very similar to the signatures expected from ejecta-CSM or ejecta-companion interaction. Apart from the pure deflagration explosion models, none of our synthetic light curves exhibit the commonly assumed power-law rise. We demonstrate that this can lead to substantial errors in the determination of the time of explosion. In summary, we illustrate with our calculations that even with very early data an identification of specific explosion scenarios is challenging, if only photometric observations are available.

  15. No evidence for bulk velocity from type Ia supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Huterer, Dragan; Shafer, Daniel L. [Department of Physics, University of Michigan, 450 Church Street, Ann Arbor, MI 48109 (United States); Schmidt, Fabian, E-mail: huterer@umich.edu, E-mail: dlshafer@umich.edu, E-mail: fabians@mpa-garching.mpg.de [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85748 Garching (Germany)

    2015-12-01

    We revisit the effect of peculiar velocities on low-redshift type Ia supernovae. Velocities introduce an additional guaranteed source of correlations between supernova magnitudes that should be considered in all analyses of nearby supernova samples but has largely been neglected in the past. Applying a likelihood analysis to the latest compilation of nearby supernovae, we find no evidence for the presence of these correlations, although, given the significant noise, the data is also consistent with the correlations predicted for the standard ΛCDM model. We then consider the dipolar component of the velocity correlations—the frequently studied ''bulk velocity''—and explicitly demonstrate that including the velocity correlations in the data covariance matrix is crucial for drawing correct and unambiguous conclusions about the bulk flow. In particular, current supernova data is consistent with no excess bulk flow on top of what is expected in ΛCDM and effectively captured by the covariance. We further clarify the nature of the apparent bulk flow that is inferred when the velocity covariance is ignored. We show that a significant fraction of this quantity is expected to be noise bias due to uncertainties in supernova magnitudes and not any physical peculiar motion.

  16. No evidence for bulk velocity from type Ia supernovae

    International Nuclear Information System (INIS)

    Huterer, Dragan; Shafer, Daniel L.; Schmidt, Fabian

    2015-01-01

    We revisit the effect of peculiar velocities on low-redshift type Ia supernovae. Velocities introduce an additional guaranteed source of correlations between supernova magnitudes that should be considered in all analyses of nearby supernova samples but has largely been neglected in the past. Applying a likelihood analysis to the latest compilation of nearby supernovae, we find no evidence for the presence of these correlations, although, given the significant noise, the data is also consistent with the correlations predicted for the standard ΛCDM model. We then consider the dipolar component of the velocity correlations—the frequently studied ''bulk velocity''—and explicitly demonstrate that including the velocity correlations in the data covariance matrix is crucial for drawing correct and unambiguous conclusions about the bulk flow. In particular, current supernova data is consistent with no excess bulk flow on top of what is expected in ΛCDM and effectively captured by the covariance. We further clarify the nature of the apparent bulk flow that is inferred when the velocity covariance is ignored. We show that a significant fraction of this quantity is expected to be noise bias due to uncertainties in supernova magnitudes and not any physical peculiar motion

  17. GAMMA RAYS FROM TYPE Ia SUPERNOVA SN 2014J

    Energy Technology Data Exchange (ETDEWEB)

    Churazov, E.; Sunyaev, R.; Grebenev, S. [Space Research Institute (IKI), Profsouznaya 84/32, Moscow 117997 (Russian Federation); Isern, J. [Institut for Space Sciences (ICE-CSIC/IEEC), E-08193 Bellaterra (Spain); Bikmaev, I. [Kazan Federal University (KFU), Kremlevskaya Strasse, 18, Kazan (Russian Federation); Bravo, E. [E.T.S.A.V., Univ. Politecnica de Catalunya, Carrer Pere Serra 1-15, E-08173 Sant Cugat del Valles (Spain); Chugai, N. [Institute of Astronomy of the Russian Academy of Sciences, 48 Pyatnitskaya Street, 119017, Moscow (Russian Federation); Jean, P.; Knödlseder, J. [Université de Toulouse, UPS-OMP, IRAP, Toulouse (France); Lebrun, F. [APC, Univ Paris Diderot, CNRS/IN2P3, CEA/Irfu, Obs de Paris, Sorbonne Paris Cité (France); Kuulkers, E. [European Space Astronomy Centre (ESA/ESAC), Science Operations Department, P.O. Box 78, E-28691 Villanueva de la Cañada, Madrid (Spain)

    2015-10-10

    The whole set of INTEGRAL observations of Type Ia supernova SN 2014J, covering the period 19–162 days after the explosion, has been analyzed. For spectral fitting the data are split into early and late periods covering days 19–35 and 50–162, respectively, optimized for {sup 56}Ni and {sup 56}Co lines. As expected for the early period, much of the gamma-ray signal is confined to energies below ∼200 keV, while for the late period it is strongest above 400 keV. In particular, in the late period, {sup 56}Co lines at 847 and 1248 keV are detected at 4.7σ and 4.3σ, respectively. The light curves in several representative energy bands are calculated for the entire period. The resulting spectra and light curves are compared with a subset of models. We confirm our previous finding that the gamma-ray data are broadly consistent with the expectations for canonical one-dimensional models, such as delayed detonation or deflagration models for a near-Chandrasekhar mass white dwarf. Late optical spectra (day 136 after the explosion) show rather symmetric Co and Fe line profiles, suggesting that, unless the viewing angle is special, the distribution of radioactive elements is symmetric in the ejecta.

  18. IA-2 autoantibody affinity in children at risk for type 1 diabetes.

    Science.gov (United States)

    Krause, Stephanie; Chmiel, Ruth; Bonifacio, Ezio; Scholz, Marlon; Powell, Michael; Furmaniak, Jadwiga; Rees Smith, Bernard; Ziegler, Anette-G; Achenbach, Peter

    2012-12-01

    Autoantibodies to insulinoma-associated protein 2 (IA-2A) are associated with increased risk for type 1 diabetes. Here we examined IA-2A affinity and epitope specificity to assess heterogeneity in response intensity in relation to pathogenesis and diabetes risk in 50 children who were prospectively followed from birth. At first IA-2A appearance, affinity ranged from 10(7) to 10(11)L/mol and was high (>1.0×10(9)L/mol) in 41 (82%) children. IA-2A affinity was not associated with epitope specificity or HLA class II haplotype. On follow-up, affinity increased or remained high, and IA-2A were commonly against epitopes within the protein tyrosine phosphatase-like IA-2 domain and the homologue protein IA-2β. IA-2A were preceded or accompanied by other islet autoantibodies in 49 (98%) children, of which 34 progressed to diabetes. IA-2A affinity did not stratify diabetes risk. In conclusion, the IA-2A response in children is intense with rapid maturation against immunogenic epitopes and a strong association with diabetes development. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. ON THE RATES OF TYPE Ia SUPERNOVAE IN DWARF AND GIANT HOSTS WITH ROTSE-IIIb

    International Nuclear Information System (INIS)

    Quimby, Robert M.; Yuan Fang; Akerlof, Carl; Wheeler, J. Craig; Warren, Michael S.

    2012-01-01

    We present a sample of 23 spectroscopically confirmed Type Ia supernovae (SNe Ia) that were discovered in the background of galaxy clusters targeted by ROTSE-IIIb and use up to 18 of these to determine the local (z-bar 0.05) volumetric rate. Since our survey is flux limited and thus biased against fainter objects, the pseudo-absolute magnitude distribution (pAMD) of SNe Ia in a given volume is an important concern, especially the relative frequency of high- to low-luminosity SNe Ia. We find that the pAMD derived from the volume-limited Lick Observatory Supernova Search (LOSS) sample is incompatible with the distribution of SNe Ia in a volume-limited (z B > –16) galaxies, whereas only 1 out of 79 nearby SDSS-II SNe Ia have such faint hosts. It is possible that previous works have undercounted either low-luminosity SNe Ia, SNe Ia in low-luminosity hosts, or peculiar SNe Ia (sometimes explicitly), and the total SNe Ia rate may be higher than the canonical value.

  20. Type-Ia Supernova Rates and the Progenitor Problem: A Review

    Science.gov (United States)

    Maoz, D.; Mannucci, F.

    2012-01-01

    The identity of the progenitor systems of type-Ia supernovae (SNe Ia) is a major unsolved problem in astrophysics. SN Ia rates are providing some striking clues. We review the basics of SN rate measurement, preach about some sins of SN rate measurement and analysis, and illustrate one of these sins with an analogy about Martian scientists. We review the recent progress in measuring SN Ia rates in various environments and redshifts, and their use to reconstruct the SN Ia delay-time distribution (DTD) - the SN rate versus time that would follow a hypothetical brief burst of star formation. A good number of DTD measurements, using a variety of methods, appear to be converging. At delays 1measurements show a similar, ~t-1, power-law shape. The DTD peaks at the shortest delays probed. This result supports the idea of a double-degenerate progenitor origin for SNe Ia. Single-degenerate progenitors may still play a role in producing short-delay SNe Ia, or perhaps all SNe Ia, if the red-giant donor channel is more efficient than is found by most theoretical models. The DTD normalization enjoys fairly good agreement (though perhaps some tension), among the various measurements, with a Hubble time-integrated DTD value of about 2+/-1 SNe Ia per 1000Msolar (stellar mass formed with a low-mass turnover initial mass function). The local WD binary population suggests that the WD merger rate can explain the Galactic SN Ia rate, but only if sub-Chandra mergers lead to SN Ia events. We point to some future directions that should lead to progress in the field, including measurement of the bivariate (delay and stretch) SN Ia response function.

  1. Type Ia supernova rate studies from the SDSS-II Supernova Study

    Energy Technology Data Exchange (ETDEWEB)

    Dilday, Benjamin [Univ. of Chicago, IL (United States)

    2008-08-01

    The author presents new measurements of the type Ia SN rate from the SDSS-II Supernova Survey. The SDSS-II Supernova Survey was carried out during the Fall months (Sept.-Nov.) of 2005-2007 and discovered ~ 500 spectroscopically confirmed SNe Ia with densely sampled (once every ~ 4 days), multi-color light curves. Additionally, the SDSS-II Supernova Survey has discovered several hundred SNe Ia candidates with well-measured light curves, but without spectroscopic confirmation of type. This total, achieved in 9 months of observing, represents ~ 15-20% of the total SNe Ia discovered worldwide since 1885. The author describes some technical details of the SN Survey observations and SN search algorithms that contributed to the extremely high-yield of discovered SNe and that are important as context for the SDSS-II Supernova Survey SN Ia rate measurements.

  2. Hepatic adenomatosis in glycogen storage disease type Ia: report of a case with unusual histology.

    Science.gov (United States)

    Volmar, Keith E; Burchette, James L; Creager, Andrew J

    2003-10-01

    Hepatic adenomatosis is a well-known complication of glycogen storage disease type Ia (von Gierke disease). Although most of these tumors have an appearance similar to sporadic hepatocellular adenomas, unusual histologic features have been reported, including Mallory hyaline, varying degrees of fibrosis, and aggregates of neutrophils. We report the fourth case of Mallory hyaline in the adenomas of glycogen storage disease type Ia in a 28-year-old woman undergoing segmental hepatectomy for enlarging liver nodules. Other prominent findings included steatohepatitis and nonspecific granulomatous inflammation--2 findings that are commonly seen in sporadic adenomas but not, to our knowledge, previously reported in glycogen storage disease type Ia.

  3. Molecular analysis of glycogen storage disease type Ia in Iranian ...

    Indian Academy of Sciences (India)

    frequency of GSD Ia and clarified its molecular aspect in patients with the main clinical and biochemical characteristics of. GSD, including 37 unrelated patients ... clinical, biochemical and enzymatic examination of the liver tissue. Based on enzyme deficiency, ..... management guidelines. Genet. Med. 12, 446–463. Koshy A.

  4. Molecular analysis of glycogen storage disease type Ia in Iranian ...

    Indian Academy of Sciences (India)

    Glycogen storage diseases (GSDs) are caused by abnormalities in enzymes that are involved in the regulation of gluconeogenesis and glycogenolysis. GSD I, an autosomal recessive metabolic disorder, is the most common GSD and has four subtypes. Here, we examined GSD Ia caused by the defective ...

  5. Neutrophilia and elevated serum cytokines are implicated in glycogen storage disease type Ia

    Science.gov (United States)

    Kim, So Youn; Chen, Li-Yuan; Yiu, Wai Han; Weinstein, David A.; Chou, Janice Y.

    2008-01-01

    Glycogen storage disease type Ia (GSD-Ia) patients deficient in glucose-6-phosphatase-α manifest a disturbed glucose homeostasis. We hypothesized that disturbed glucose homeostasis might affect myeloid functions. Here we show that GSD-Ia mice exhibit normal neutrophil activities but have elevated myeloid progenitor cells in the bone marrow and spleen. Interestingly, GSD-Ia mice exhibit a persistent increase in peripheral blood neutrophil counts along with elevated serum levels of granulocyte colony stimulating factor and cytokine-induced neutrophil chemoattractant. Taken together, our results suggest that a loss of glucose homeostasis can compromise the immune system, resulting in neutrophilia. This may explain some of the unexpected clinical manifestations seen in GSD-Ia. PMID:17659284

  6. Swift X-Ray Upper Limits on Type Ia Supernova Environments

    Science.gov (United States)

    Russell, B. R.; Immler, S.

    2012-01-01

    We have considered 53 Type Ia supernovae (SNe Ia) observed by the Swift X-Ray Telescope. None of the SNe Ia are individually detected at any time or in stacked images. Using these data and assuming that the SNe Ia are a homogeneous class of objects, we have calculated upper limits to the X-ray luminosity (0.2-10 keV) and mass-loss rate of L(sub 0.2-10) < 1.7 X 10(exp 38) erg/s and M(dot) < l.l X 10(exp -6) solar M/ yr x (V(sub w))/(10 km/s), respectively. The results exclude massive or evolved stars as the companion objects in SN Ia progenitor systems, but allow the possibility of main sequence or small stars, along with double degenerate systems consisting of two white dwarfs, consistent with results obtained at other wavelengths (e.g., UV, radio) in other studies.

  7. Testing the isotropy of the Universe with Type Ia supernovae in a model-independent way

    Science.gov (United States)

    Wang, Yu-Yang; Wang, F. Y.

    2018-03-01

    In this paper, we study an anisotropic universe model with Bianchi-I metric using Joint light-curve analysis (JLA) sample of Type Ia supernovae (SNe Ia). Because light-curve parameters of SNe Ia vary with different cosmological models and SNe Ia samples, we fit the SNe Ia light-curve parameters and cosmological parameters simultaneously employing Markov chain Monte Carlo method. Therefore, the results on the amount of deviation from isotropy of the dark energy equation of state (δ), and the level of anisotropy of the large-scale geometry (Σ0) at present, are totally model-independent. The constraints on the skewness and cosmic shear are -0.101 universe (δ = Σ0 = 0). However, a moderate level of anisotropy in the geometry of the Universe and the equation of state of dark energy, is allowed. Besides, there is no obvious evidence for a preferred direction of anisotropic axis in this model.

  8. Activation of glycolysis and apoptosis in glycogen storage disease type Ia.

    Science.gov (United States)

    Sun, Baodong; Li, Songtao; Yang, Liu; Damodaran, Tirupapuliyur; Desai, Dev; Diehl, Anna Mae; Alzate, Oscar; Koeberl, Dwight D

    2009-08-01

    The deficiency of glucose-6-phosphatase (G6Pase) underlies glycogen storage disease type Ia (GSD-Ia, von Gierke disease; MIM 232200), an autosomal recessive disorder of metabolism associated with life-threatening hypoglycemia, growth retardation, renal failure, hepatic adenomas, and hepatocellular carcinoma. Liver involvement includes the massive accumulation of glycogen and lipids due to accumulated glucose-6-phosphate and glycolytic intermediates. Proteomic analysis revealed elevations in glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and other enzymes involved in glycolysis. GAPDH was markedly increased in murine G6Pase-deficient hepatocytes. The moonlighting role of GAPDH includes increasing apoptosis, which was demonstrated by increased TUNEL assay positivity and caspase 3 activation in the murine GSD-Ia liver. These analyses of hepatic involvement in GSD-Ia mice have implicated the induction of apoptosis in the pathobiology of GSD-Ia.

  9. Measuring the Growth Rate of Structure with Type IA Supernovae from LSST

    Science.gov (United States)

    Howlett, Cullan; Robotham, Aaron S. G.; Lagos, Claudia D. P.; Kim, Alex G.

    2017-10-01

    We investigate the peculiar motions of galaxies up to z = 0.5 using Type Ia supernovae (SNe Ia) from the Large Synoptic Survey Telescope (LSST) and predict the subsequent constraints on the growth rate of structure. We consider two cases. Our first is based on measurements of the volumetric SNe Ia rate and assumes we can obtain spectroscopic redshifts and light curves for varying fractions of objects that are detected pre-peak luminosity by LSST (some of which may be obtained by LSST itself, and others that would require additional follow-up observations). We find that these measurements could produce growth rate constraints at zIa rate as a function of stellar mass and star-formation rate to predict the number of LSST SNe IA whose host redshifts may already have been obtained with the Taipan+WALLABY surveys or with a future multi-object spectroscopic survey. We find ˜18,000 and ˜160,000 SNe Ia with host redshifts for these cases, respectively. While this is only a fraction of the total LSST-detected SNe Ia, they could be used to significantly augment and improve the growth rate constraints compared to only RSD. Ultimately, we find that combining LSST SNe Ia with large numbers of galaxy redshifts will provide the most powerful probe of large-scale gravity in the z< 0.5 regime over the coming decades.

  10. The Effect of Host Galaxies on Type Ia Supernovae in the SDSS-II Supernova Survey

    Energy Technology Data Exchange (ETDEWEB)

    Lampeitl, Hubert; /Portsmouth U., ICG; Smith, Mathew; /Cape Town U. /Portsmouth U., ICG; Nichol, Robert C.; /Portsmouth U., ICG; Bassett, Bruce; /South African Astron. Observ. /Cape Town U.; Cinabro, David; /Wayne State U.; Dilday, Benjamin; /Rutgers U., Piscataway; Foley, Ryan J.; /Harvard-Smithsonian Ctr. Astrophys.; Frieman, Joshua A.; /Chicago U. /Fermilab; Garnavich, Peter M.; /Notre Dame U.; Goobar, Ariel; /Stockholm U., OKC; Im, Myungshin; /Seoul Natl. U. /Rutgers U., Piscataway

    2010-05-01

    We present an analysis of the host galaxy dependencies of Type Ia Supernovae (SNe Ia) from the full three year sample of the SDSS-II Supernova Survey. We re-discover, to high significance, the strong correlation between host galaxy type and the width of the observed SN light curve, i.e., fainter, quickly declining SNe Ia favor passive host galaxies, while brighter, slowly declining Ia's favor star-forming galaxies. We also find evidence (at between 2 to 3{sigma}) that SNe Ia are {approx_equal} 0.1 magnitudes brighter in passive host galaxies, than in star-forming hosts, after the SN Ia light curves have been standardized using the light curve shape and color variations: This difference in brightness is present in both the SALT2 and MCLS2k2 light curve fitting methodologies. We see evidence for differences in the SN Ia color relationship between passive and star-forming host galaxies, e.g., for the MLCS2k2 technique, we see that SNe Ia in passive hosts favor a dust law of R{sub V} {approx_equal} 1, while SNe Ia in star-forming hosts require R{sub V} {approx} 2. The significance of these trends depends on the range of SN colors considered. We demonstrate that these effects can be parameterized using the stellar mass of the host galaxy (with a confidence of > 4{sigma}) and including this extra parameter provides a better statistical fit to our data. Our results suggest that future cosmological analyses of SN Ia samples should include host galaxy information.

  11. Stone forming risk factors in patients with type Ia glycogen storage disease.

    Science.gov (United States)

    Scales, Charles D; Chandrashekar, Aravind S; Robinson, Marnie R; Cantor, David A; Sullivan, Jennifer; Haleblian, George E; Leitao, Victor A; Sur, Roger L; Borawski, Kristy M; Koeberl, Dwight; Kishnani, Priya S; Preminger, Glenn M

    2010-03-01

    Patients with type Ia glycogen storage disease have an increased recurrent nephrolithiasis rate. We identified stone forming risk factors in patients with type Ia glycogen storage disease vs those in stone formers without the disease. Patients with type Ia glycogen storage disease were prospectively enrolled from our metabolic clinic. Patient 24-hour urine parameters were compared to those in age and gender matched stone forming controls. We collected 24-hour urine samples from 13 patients with type Ia glycogen storage disease. Average +/- SD age was 27.0 +/- 13.0 years and 6 patients (46%) were male. Compared to age and gender matched hypocitraturic, stone forming controls patients had profound hypocitraturia (urinary citrate 70 vs 344 mg daily, p = 0.009). When comparing creatinine adjusted urinary values, patients had profound hypocitraturia (0.119 vs 0.291 mg/mg creatinine, p = 0.005) and higher oxalate (0.026 vs 0.021 mg/mg creatinine, p = 0.038) vs other stone formers. Patients with type Ia glycogen storage disease have profound hypocitraturia, as evidenced by 24-hour urine collections, even compared to other stone formers. This may be related to a recurrent nephrolithiasis rate greater than in the overall population. These findings may be used to support different treatment modalities, timing and/or doses to prevent urinary lithiasis in patients with type Ia glycogen storage disease. 2010 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  12. 3D non-LTE spectrum synthesis for Type Ia supernovae

    OpenAIRE

    Kromer, M.; Sim, S. A.; Hillebrandt, W.

    2009-01-01

    Despite the importance of Type Ia supernovae as standard candles for cosmology and to the chemical evolution of the Universe, we still have no consistent picture of the nature of these events. Much progress has been made in the hydrodynamical explosion modelling of supernovae Ia in the last few years and fully 3-D explosion models are now available. However those simulations are not directly comparable to observations: to constrain explosion models, radiative transfer calculations must be car...

  13. Manganese spread in Ursa Minor as a proof of sub-classes of type Ia supernovae

    OpenAIRE

    Cescutti, Gabriele; Kobayashi, Chiaki

    2017-01-01

    Context. Recently, new sub-classes of Type Ia supernovae (SNe Ia) were discovered, including SNe Iax. The suggested progenitors of SNe Iax are relatively massive, possibly hybrid C+O+Ne white dwarfs, which can cause white dwarf winds at low metallicities. There is another class that can potentially occur at low or zero metallicities; sub-Chandrasekhar mass explosions in single and/or double degenerate systems of standard C+O white dwarfs. These explosions have different nucleosynthesis yields...

  14. HOST GALAXIES OF TYPE Ia SUPERNOVAE FROM THE NEARBY SUPERNOVA FACTORY

    International Nuclear Information System (INIS)

    Childress, M.; Aldering, G.; Aragon, C.; Bailey, S.; Fakhouri, H. K.; Hsiao, E. Y.; Kim, A. G.; Loken, S.; Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Guy, J.; Baltay, C.; Buton, C.; Kerschhaggl, M.; Kowalski, M.; Chotard, N.; Copin, Y.; Gangler, E.

    2013-01-01

    We present photometric and spectroscopic observations of galaxies hosting Type Ia supernovae (SNe Ia) observed by the Nearby Supernova Factory. Combining Galaxy Evolution Explorer (GALEX) UV data with optical and near-infrared photometry, we employ stellar population synthesis techniques to measure SN Ia host galaxy stellar masses, star formation rates (SFRs), and reddening due to dust. We reinforce the key role of GALEX UV data in deriving accurate estimates of galaxy SFRs and dust extinction. Optical spectra of SN Ia host galaxies are fitted simultaneously for their stellar continua and emission lines fluxes, from which we derive high-precision redshifts, gas-phase metallicities, and Hα-based SFRs. With these data we show that SN Ia host galaxies present tight agreement with the fiducial galaxy mass-metallicity relation from Sloan Digital Sky Survey (SDSS) for stellar masses log(M * /M ☉ ) > 8.5 where the relation is well defined. The star formation activity of SN Ia host galaxies is consistent with a sample of comparable SDSS field galaxies, though this comparison is limited by systematic uncertainties in SFR measurements. Our analysis indicates that SN Ia host galaxies are, on average, typical representatives of normal field galaxies.

  15. ON THE DEPENDENCE OF TYPE Ia SNe LUMINOSITIES ON THE METALLICITY OF THEIR HOST GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Moreno-Raya, Manuel E.; Mollá, Mercedes [Dpto.de Investigación Básica, C.I.E.M.A.T., Avda. Complutense 40, E-28040 Madrid (Spain); López-Sánchez, Ángel R. [Australian Astronomical Observatory, P.O. Box 915, North Ryde, NSW 1670 (Australia); Galbany, Lluís [Millennium Institute of Astrophysics MAS, Nuncio Monseñor Sótero Sanz 100, Providencia, 7500011 Santiago (Chile); Vílchez, José Manuel [Instituto de Astrofísica de Andalucía (CSIC), Apdo. 3004, E-18080 Granada (Spain); Rosell, Aurelio Carnero [Observatório Nacional, and LIneA Laboratório Interinstitucional de e-Astronomia, Rua Gal. José Cristino 77 Rio de Janeiro, RJ 20921-400 (Brazil); Domínguez, Inmaculada, E-mail: manuelemilio.moreno@ciemat.es [Departamento de Física Teórica y del Cosmos, Universidad de Granada, E-18071 Granada (Spain)

    2016-02-10

    The metallicity of the progenitor system producing a type Ia supernova (SN Ia) could play a role in its maximum luminosity, as suggested by theoretical predictions. We present an observational study to investigate if such a relationship exists. Using the 4.2 m William Herschel Telescope (WHT) we have obtained intermediate-resolution spectroscopy data of a sample of 28 local galaxies hosting SNe Ia, for which distances have been derived using methods independent of those based on SN Ia parameters. From the emission lines observed in their optical spectra, we derived the gas-phase oxygen abundance in the region where each SN Ia exploded. Our data show a trend, with an 80% of chance not being due to random fluctuation, between SNe Ia absolute magnitudes and the oxygen abundances of the host galaxies, in the sense that luminosities tend to be higher for galaxies with lower metallicities. This result seems likely to be in agreement with both the theoretically expected behavior and with other observational results. This dependence M{sub B}–Z might induce systematic errors when it is not considered when deriving SNe Ia luminosities and then using them to derive cosmological distances.

  16. THE DISCOVERY OF THE MOST DISTANT KNOWN TYPE Ia SUPERNOVA AT REDSHIFT 1.914

    International Nuclear Information System (INIS)

    Jones, David O.; Rodney, Steven A.; Riess, Adam G.; Mobasher, Bahram; Dahlen, Tomas; Casertano, Stefano; Koekemoer, Anton; McCully, Curtis; Keeton, Charles R.; Patel, Brandon; Frederiksen, Teddy F.; Hjorth, Jens; Strolger, Louis-Gregory; Wiklind, Tommy G.; Challis, Peter; Graur, Or; Hayden, Brian; Garnavich, Peter; Weiner, Benjamin J.; Filippenko, Alexei V.

    2013-01-01

    We present the discovery of a Type Ia supernova (SN) at redshift z = 1.914 from the CANDELS multi-cycle treasury program on the Hubble Space Telescope (HST). This SN was discovered in the infrared using the Wide-Field Camera 3, and it is the highest-redshift Type Ia SN yet observed. We classify this object as a SN Ia by comparing its light curve and spectrum with those of a large sample of Type Ia and core-collapse SNe. Its apparent magnitude is consistent with that expected from the ΛCDM concordance cosmology. We discuss the use of spectral evidence for classification of z > 1.5 SNe Ia using HST grism simulations, finding that spectral data alone can frequently rule out SNe II, but distinguishing between SNe Ia and SNe Ib/c can require prohibitively long exposures. In such cases, a quantitative analysis of the light curve may be necessary for classification. Our photometric and spectroscopic classification methods can aid the determination of SN rates and cosmological parameters from the full high-redshift CANDELS SN sample.

  17. The discovery of the most distant known type Ia supernova at redshift 1.914

    DEFF Research Database (Denmark)

    Jones, Dennis; Rodney, S.A.; Riess, A.G.

    2013-01-01

    We present the discovery of a Type Ia supernova (SN) at redshift z = 1.914 from the CANDELS multi-cycle treasury program on the Hubble Space Telescope (HST). This SN was discovered in the infrared using the Wide-Field Camera 3, and it is the highest-redshift Type Ia SN yet observed. We classify...... this object as a SN Ia by comparing its light curve and spectrum with those of a large sample of Type Ia and core-collapse SNe. Its apparent magnitude is consistent with that expected from the ¿CDM concordance cosmology. We discuss the use of spectral evidence for classification of z > 1.5 SNe Ia using HST...... grism simulations, finding that spectral data alone can frequently rule out SNe II, but distinguishing between SNe Ia and SNe Ib/c can require prohibitively long exposures. In such cases, a quantitative analysis of the light curve may be necessary for classification. Our photometric and spectroscopic...

  18. CfA3: 185 TYPE Ia SUPERNOVA LIGHT CURVES FROM THE CfA

    International Nuclear Information System (INIS)

    Hicken, Malcolm; Challis, Peter; Kirshner, Robert P.; Bakos, Gaspar; Berlind, Perry; Brown, Warren R.; Caldwell, Nelson; Calkins, Mike; Cho, Richard; Contreras, Maria; Jha, Saurabh; Matheson, Tom; Modjaz, Maryam; Rest, Armin; Michael Wood-Vasey, W.; Barton, Elizabeth J.; Bragg, Ann; Briceno, Cesar; Ciupik, Larry; Dendy, Kristi-Concannon

    2009-01-01

    We present multiband photometry of 185 type-Ia supernovae (SNe Ia), with over 11,500 observations. These were acquired between 2001 and 2008 at the F. L. Whipple Observatory of the Harvard-Smithsonian Center for Astrophysics (CfA). This sample contains the largest number of homogeneously observed and reduced nearby SNe Ia (z ∼< 0.08) published to date. It more than doubles the nearby sample, bringing SN Ia cosmology to the point where systematic uncertainties dominate. Our natural system photometry has a precision of ∼<0.02 mag in BVRIr'i' and ∼<0.04 mag in U for points brighter than 17.5 mag. We also estimate a systematic uncertainty of 0.03 mag in our SN Ia standard system BVRIr'i' photometry and 0.07 mag for U. Comparisons of our standard system photometry with published SN Ia light curves and comparison stars, where available for the same SN, reveal agreement at the level of a few hundredths mag in most cases. We find that 1991bg-like SNe Ia are sufficiently distinct from other SNe Ia in their color and light-curve-shape/luminosity relation that they should be treated separately in light-curve/distance fitter training samples. The CfA3 sample will contribute to the development of better light-curve/distance fitters, particularly in the few dozen cases where near-infrared photometry has been obtained and, together, can help disentangle host-galaxy reddening from intrinsic supernova color, reducing the systematic uncertainty in SN Ia distances due to dust.

  19. Precise Time Delays from Strongly Gravitationally Lensed Type Ia Supernovae with Chromatically Microlensed Images

    Science.gov (United States)

    Goldstein, Daniel A.; Nugent, Peter E.; Kasen, Daniel N.; Collett, Thomas E.

    2018-03-01

    Time delays between the multiple images of strongly gravitationally lensed Type Ia supernovae (glSNe Ia) have the potential to deliver precise cosmological constraints, but the effects of microlensing on time delay extraction have not been studied in detail. Here we quantify the effect of microlensing on the glSN Ia yield of the Large Synoptic Survey Telescope (LSST) and the effect of microlensing on the precision and accuracy of time delays that can be extracted from LSST glSNe Ia. Microlensing has a negligible effect on the LSST glSN Ia yield, but it can be increased by a factor of ∼2 over previous predictions to 930 systems using a novel photometric identification technique based on spectral template fitting. Crucially, the microlensing of glSNe Ia is achromatic until three rest-frame weeks after the explosion, making the early-time color curves microlensing-insensitive time delay indicators. By fitting simulated flux and color observations of microlensed glSNe Ia with their underlying, unlensed spectral templates, we forecast the distribution of absolute time delay error due to microlensing for LSST, which is unbiased at the sub-percent level and peaked at 1% for color curve observations in the achromatic phase, while for light-curve observations it is comparable to state-of-the-art mass modeling uncertainties (4%). About 70% of LSST glSN Ia images should be discovered during the achromatic phase, indicating that microlensing time delay uncertainties can be minimized if prompt multicolor follow-up observations are obtained. Accounting for microlensing, the 1–2 day time delay on the recently discovered glSN Ia iPTF16geu can be measured to 40% precision, limiting its cosmological utility.

  20. Gastric cancer following a liver transplantation for glycogen storage disease type Ia (von Gierke disease): A case report

    OpenAIRE

    XIAO, HUA; BIAN, JIANMIN; ZHANG, LEI; WANG, ZHAOMING; DING, AIXING

    2014-01-01

    Glycogen storage disease type Ia (GSD-Ia; also termed von Gierke disease) is an inherited metabolic disorder resulting from a glucose-6-phosphatase deficiency. Liver transplantation is considered to be the most effective treatment for GSD-Ia patients. In the present study, the case of a patient with GSD-Ia who received a liver transplantation at 17 years of age is presented. During the 12 years following transplantation, the patient’s quality of life markedly improved. However, recently, the ...

  1. Stochastic gravitational wave background from the single-degenerate channel of type Ia supernovae

    International Nuclear Information System (INIS)

    Falta, David; Fisher, Robert

    2011-01-01

    We demonstrate that the integrated gravitational wave signal of type Ia supernovae (SNe Ia) in the single-degenerate channel out to cosmological distances gives rise to a continuous background to spaceborne gravitational wave detectors, including the Big Bang Observer and Deci-Hertz Interferometer Gravitational wave Observatory planned missions. This gravitational wave background from SNe Ia acts as a noise background in the frequency range 0.1-10 Hz, which heretofore was thought to be relatively free from astrophysical sources apart from neutron-star and white-dwarf binaries, and therefore a key window in which to study primordial gravitational waves generated by inflation. While inflationary energy scales of > or approx. 10 16 GeV yield inflationary gravitational wave backgrounds in excess of our range of predicted backgrounds, for lower energy scales of ∼10 15 GeV, the inflationary gravitational wave background becomes comparable to the noise background from SNe Ia.

  2. PTF 11kx: a type Ia supernova with a symbiotic nova progenitor.

    Science.gov (United States)

    Dilday, B; Howell, D A; Cenko, S B; Silverman, J M; Nugent, P E; Sullivan, M; Ben-Ami, S; Bildsten, L; Bolte, M; Endl, M; Filippenko, A V; Gnat, O; Horesh, A; Hsiao, E; Kasliwal, M M; Kirkman, D; Maguire, K; Marcy, G W; Moore, K; Pan, Y; Parrent, J T; Podsiadlowski, P; Quimby, R M; Sternberg, A; Suzuki, N; Tytler, D R; Xu, D; Bloom, J S; Gal-Yam, A; Hook, I M; Kulkarni, S R; Law, N M; Ofek, E O; Polishook, D; Poznanski, D

    2012-08-24

    There is a consensus that type Ia supernovae (SNe Ia) arise from the thermonuclear explosion of white dwarf stars that accrete matter from a binary companion. However, direct observation of SN Ia progenitors is lacking, and the precise nature of the binary companion remains uncertain. A temporal series of high-resolution optical spectra of the SN Ia PTF 11kx reveals a complex circumstellar environment that provides an unprecedentedly detailed view of the progenitor system. Multiple shells of circumstellar material are detected, and the SN ejecta are seen to interact with circumstellar material starting 59 days after the explosion. These features are best described by a symbiotic nova progenitor, similar to RS Ophiuchi.

  3. Confronting Alternative Cosmological Models with the Highest-Redshift Type Ia Supernovae

    Science.gov (United States)

    Shafer, Daniel; Scolnic, Daniel; Riess, Adam

    2018-01-01

    High-redshift Type Ia supernovae (SNe Ia) from the HST CANDELS and CLASH programs significantly extend the Hubble diagram with 7 SNe at z > 1.5 suitable for cosmology, including one at z = 2.3. This unique leverage helps us distinguish "alternative" cosmological models from the standard Lambda-CDM model. Analyzing the Pantheon SN compilation, which includes these high-z SNe, we employ model comparison statistics to quantify the extent to which several proposed alternative expansion histories (e.g., empty universe, power law expansion, timescape cosmology) are disfavored even with SN Ia data alone. Using mock data, we demonstrate that some likelihood analyses used in the literature to support these models are sensitive to unrealistic assumptions and are therefore unsuitable for analysis of realistic SN Ia data.

  4. Observational Evidence for High Neutronization in Supernova Remnants: Implications for Type Ia Supernova Progenitors

    Science.gov (United States)

    Martínez-Rodríguez, Héctor; Badenes, Carles; Yamaguchi, Hiroya; Bravo, Eduardo; Timmes, F. X.; Miles, Broxton J.; Townsley, Dean M.; Piro, Anthony L.; Mori, Hideyuki; Andrews, Brett; Park, Sangwook

    2017-07-01

    The physical process whereby a carbon-oxygen white dwarf explodes as a Type Ia supernova (SN Ia) remains highly uncertain. The degree of neutronization in SN Ia ejecta holds clues to this process because it depends on the mass and the metallicity of the stellar progenitor, and on the thermodynamic history prior to the explosion. We report on a new method to determine ejecta neutronization using Ca and S lines in the X-ray spectra of Type Ia supernova remnants (SNRs). Applying this method to Suzaku data of Tycho, Kepler, 3C 397, and G337.2-0.7 in the Milky Way, and N103B in the Large Magellanic Cloud, we find that the neutronization of the ejecta in N103B is comparable to that of Tycho and Kepler, which suggests that progenitor metallicity is not the only source of neutronization in SNe Ia. We then use a grid of SN Ia explosion models to infer the metallicities of the stellar progenitors of our SNRs. The implied metallicities of 3C 397, G337.2-0.7, and N103B are major outliers compared to the local stellar metallicity distribution functions, indicating that progenitor metallicity can be ruled out as the origin of neutronization for these SNRs. Although the relationship between ejecta neutronization and equivalent progenitor metallicity is subject to uncertainties stemming from the 12C + 16O reaction rate, which affects the Ca/S mass ratio, our main results are not sensitive to these details.

  5. Near-infrared light curves of Type Ia supernovae: studying properties of the second maximum

    Science.gov (United States)

    Dhawan, S.; Leibundgut, B.; Spyromilio, J.; Maguire, K.

    2015-04-01

    Type Ia supernovae (SNe Ia) have been proposed to be much better distance indicators at near-infrared (NIR) compared to optical wavelengths - the effect of dust extinction is expected to be lower and it has been shown that SNe Ia behave more like `standard candles' at NIR wavelengths. To better understand the physical processes behind this increased uniformity, we have studied the Y, J and H-filter light curves of 91 SNe Ia from the literature. We show that the phases and luminosities of the first maximum in the NIR light curves are extremely uniform for our sample. The phase of the second maximum, the late-phase NIR luminosity and the optical light-curve shape are found to be strongly correlated, in particular more luminous SNe Ia reach the second maximum in the NIR filters at a later phase compared to fainter objects. We also find a strong correlation between the phase of the second maximum and the epoch at which the SN enters the Lira law phase in its optical colour curve (epochs ˜ 15 to 30 d after B-band maximum). The decline rate after the second maximum is very uniform in all NIR filters. We suggest that these observational parameters are linked to the nickel and iron mass in the explosion, providing evidence that the amount of nickel synthesized in the explosion is the dominating factor shaping the optical and NIR appearance of SNe Ia.

  6. Cosmological Parameter Uncertainties from SALT-II Type Ia Supernova Light Curve Models

    Energy Technology Data Exchange (ETDEWEB)

    Mosher, J. [Pennsylvania U.; Guy, J. [LBL, Berkeley; Kessler, R. [Chicago U., KICP; Astier, P. [Paris U., VI-VII; Marriner, J. [Fermilab; Betoule, M. [Paris U., VI-VII; Sako, M. [Pennsylvania U.; El-Hage, P. [Paris U., VI-VII; Biswas, R. [Argonne; Pain, R. [Paris U., VI-VII; Kuhlmann, S. [Argonne; Regnault, N. [Paris U., VI-VII; Frieman, J. A. [Fermilab; Schneider, D. P. [Penn State U.

    2014-08-29

    We use simulated type Ia supernova (SN Ia) samples, including both photometry and spectra, to perform the first direct validation of cosmology analysis using the SALT-II light curve model. This validation includes residuals from the light curve training process, systematic biases in SN Ia distance measurements, and a bias on the dark energy equation of state parameter w. Using the SN-analysis package SNANA, we simulate and analyze realistic samples corresponding to the data samples used in the SNLS3 analysis: ~120 low-redshift (z < 0.1) SNe Ia, ~255 Sloan Digital Sky Survey SNe Ia (z < 0.4), and ~290 SNLS SNe Ia (z ≤ 1). To probe systematic uncertainties in detail, we vary the input spectral model, the model of intrinsic scatter, and the smoothing (i.e., regularization) parameters used during the SALT-II model training. Using realistic intrinsic scatter models results in a slight bias in the ultraviolet portion of the trained SALT-II model, and w biases (w (input) – w (recovered)) ranging from –0.005 ± 0.012 to –0.024 ± 0.010. These biases are indistinguishable from each other within the uncertainty, the average bias on w is –0.014 ± 0.007.

  7. The blue anbd visual absolute magnitude distributions of Type IA supernovae

    Science.gov (United States)

    Vaughan, Thomas E.; Branch, David; Miller, Douglas L.; Perlmutter, Saul

    1995-02-01

    Tully-Fisher (TF), surface brightness fluctuation (SBF), and Hubble law distances to the parent galaxies of Type Ia supernovae (SNs Ia) are used in order to study the SN Ia blue and visual peak absolute magnitude (MB and MV) distributions. We propose two objective cuts, each of which produces a subsample with small intrinsic dispersion in M. One cut, which can be applied to either band, distinguishes between a subsample of bright events and a smaller subsample of dim events, some of which were extinquished in the parent galaxy and some of which were intrinsically subluminous. The bright events are found to be distributed with an observed dispersions of 0.3 less than or approximately = Sigmaobs less than or approximately = 0.4 about a mean absolut magnitude (M-barB or M-barV). Each of the dim SNs was spectroscopically peculiar and/or had a red B-V color; this motivates the adoption of an alternative cut that is based on B-V rather than on M. To wit, SNs Ia that are both known to have -0.25 less than B-V less than + 0.25 and not known to be spectroscopically peculiar show observational dispersion of only Sigmaobs(MB) = Sigmaobs(MV) = 0.3. Because characteristics observational errors produce Sigmaerr(M) greater than 0.2,the intrinsic dispersion among such SNs Ia is Sigmaint(M) less than or approximately = 0.2. The small observational dispersion indicates that SNs Ia, the TF relation, and SBFs all good relative distances to those galaxies that produce SNs Ia. The conflict between those who use SNs Ia in order to determine the value of the Hubble constant (H0) and those who use TF and SBF distances to determine H0 results from discrepant calibrations.

  8. Measuring the Hubble constant with Type Ia supernovae as near-infrared standard candles

    Science.gov (United States)

    Dhawan, Suhail; Jha, Saurabh W.; Leibundgut, Bruno

    2018-01-01

    The most precise local measurements of H0 rely on observations of Type Ia supernovae (SNe Ia) coupled with Cepheid distances to SN Ia host galaxies. Recent results have shown tension comparing H0 to the value inferred from CMB observations assuming ΛCDM, making it important to check for potential systematic uncertainties in either approach. To date, precise local H0 measurements have used SN Ia distances based on optical photometry, with corrections for light curve shape and colour. Here, we analyse SNe Ia as standard candles in the near-infrared (NIR), where luminosity variations in the supernovae and extinction by dust are both reduced relative to the optical. From a combined fit to 9 nearby calibrator SNe with host Cepheid distances from Riess et al. (2016) and 27 SNe in the Hubble flow, we estimate the absolute peak J magnitude MJ = -18.524 ± 0.041 mag and H0 = 72.8 ± 1.6 (statistical) ±2.7 (systematic) km s-1 Mpc-1. The 2.2% statistical uncertainty demonstrates that the NIR provides a compelling avenue to measuring SN Ia distances, and for our sample the intrinsic (unmodeled) peak J magnitude scatter is just 0.10 mag, even without light curve shape or colour corrections. Our results do not vary significantly with different sample selection criteria, though photometric calibration in the NIR may be a dominant systematic uncertainty. Our findings suggest that tension in the competing H0 distance ladders is likely not a result of supernova systematics that could be expected to vary between optical and NIR wavelengths, like dust extinction. We anticipate further improvements in H0 with a larger calibrator sample of SNe Ia with Cepheid distances, more Hubble flow SNe Ia with NIR light curves, and better use of the full NIR photometric data set beyond simply the peak J-band magnitude.

  9. Use of modified cornstarch therapy to extend fasting in glycogen storage disease types Ia and Ib

    NARCIS (Netherlands)

    Correia, Catherine E.; Bhattacharya, Kaustuv; Lee, Philip J.; Shuster, Jonathan J.; Theriaque, Douglas W.; Shankar, Meena N.; Smit, G. Peter A.; Weinstein, David A.

    2008-01-01

    Background: Type I glycogen storage disease (GSD) is caused by a deficiency of glucose-6-phosphatase resulting in severe fasting hypoglycemia. Objective: We compared the efficacy of a new modified starch with the currently used cornstarch therapy in patients with type Ia and Ib GSD. Design: This was

  10. LUMINOSITY FUNCTIONS OF TYPE Ia SUPERNOVAE AND THEIR HOST GALAXIES FROM THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Yasuda, Naoki; Fukugita, Masataka

    2010-01-01

    The sample of 137 low-redshift type Ia supernovae (SNe Ia) with 0.05 ≤ z ≤ 0.3 obtained from the Sloan Digital Sky Survey (SDSS)-II supernova survey for the southern equatorial stripe of 300 deg 2 is used to derive the luminosity functions (LFs) of SNe Ia and of their host galaxies in the g, r, i passbands. We show that the LF of SNe Ia host galaxies matches well with that of galaxies in the general field, suggesting that the occurrence of SNe Ia does not favor a particular type of galaxy but is predominantly proportional to the luminosity of galaxies. The evidence is weak that the SNe rate varies with the color of host galaxies. The only evidence that points to possible correlation between the SN rate and star formation activity is that the SN rate in late-type galaxies is higher than that in early-type galaxies by 31% ± 35%. In our low-redshift sample, the component of type Ia SN rate that is proportional to star formation activity is not evident in the integrated SN rate, while our observation is compatible with the current two-component models. The sample contains eight SNe Ia whose host galaxies were not identified, but it is shown that their occurrence is consistent with them occurring in low-luminous galaxies beyond the survey. The LF of SNe Ia is approximately Gaussian with the full width at half-maximum being a factor of σ = 0.24 mag or 1.67 in luminosity. The Gaussian distribution becomes tighter if the ratio of extinction to reddening, R V , is lower than the characteristic value for the Milky Way and if luminosity is corrected for the light-curve shape. The average color excess is ∼0.07 mag, which is significantly smaller than reddening expected for field galaxies. This color excess does not vary with the distance of the SNe from the center of the host galaxy to 15 kpc. This suggests that the major part of the color excess appears to be either intrinsic or reddening that arises in the immediate environment of SNe, rather than interstellar

  11. Select early type IA endoleaks after endovascular aneurysm repair will resolve without secondary intervention.

    Science.gov (United States)

    O'Donnell, Thomas F X; Corey, Michael R; Deery, Sarah E; Tsougranis, Gregory; Maruthi, Rohit; Clouse, W Darrin; Cambria, Richard P; Conrad, Mark F

    2018-01-01

    Although it is traditionally considered ominous, the natural history of early proximal attachment site endoleaks (IA) after endovascular aneurysm repair (EVAR) is not well known. Our aim was to identify risk factors for persistent type IA endoleaks and to determine their effect on long-term outcomes after EVAR. All patients who underwent infrarenal EVAR at a single institution between 1998 and 2015 were identified. Preoperative axial imaging and intraoperative arteriograms were reviewed, and those patients with a type IA endoleak were further studied. Aneurysm features were characterized by two reviewers and were studied for predictors of persistent endoleaks at the conclusion of the case. Patient records and the Social Security Death Index were used to record 1-year and overall survival. We identified 1484 EVARs, 122 (8%) of which were complicated by a type IA endoleak on arteriography after graft deployment, with a median follow-up of 4 years. The majority of patients underwent additional ballooning of the proximal site (52 [43%]) or placement of an aortic cuff (47 [39%]); 30 patients (25%) received a Palmaz stent, and four patients were treated with coils or anchors. At case end, only 43 (35%) of the type IA endoleaks remained; at 1 month, only 16 endoleaks persisted (13%), and only six persisted at 1 year (6%). In multivariable analysis, the only independent predictor of persistence of type IA endoleak at the conclusion of the case was the presence of extensive neck calcifications (odds ratio [OR], 9.9; 95% confidence interval [CI], 1.4-67.9; P = .02). Thirteen patients (11%) underwent reintervention for type IA endoleaks, with a time frame ranging from 3 days postoperatively to 11 years. There were three patients (2.4%) who experienced aneurysm rupture. Postoperative type IA endoleak was associated with lower survival at 1 year (79% vs 91%; relative risk, 2.5; 95% CI, 1.1-5.4; P = .02), but it did not affect long-term survival (log-rank, P = .45

  12. Prevention of complications in glycogen storage disease type Ia with optimization of metabolic control.

    Science.gov (United States)

    Dambska, M; Labrador, E B; Kuo, C L; Weinstein, D A

    2017-08-01

    Prior to 1971, type Ia glycogen storage disease was marked by life-threatening hypoglycemia, lactic acidosis, severe failure to thrive, and developmental delay. With the introduction of continuous feeds in the 1970s and cornstarch in the 1980s, the prognosis improved, but complications almost universally developed. Changes in the management of type Ia glycogen storage disease have resulted in improved metabolic control, and this manuscript reviews the increasing evidence that complications can be delayed or prevented with optimal metabolic control as previously was seen in diabetes. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. SN 2006bt: A PERPLEXING, TROUBLESOME, AND POSSIBLY MISLEADING TYPE Ia SUPERNOVA

    International Nuclear Information System (INIS)

    Foley, Ryan J.; Narayan, Gautham; Challis, Peter J.; Kirshner, Robert P.; Filippenko, Alexei V.; Silverman, Jeffrey M.; Steele, Thea N.

    2010-01-01

    SN 2006bt displays characteristics unlike those of any other known Type Ia supernova (SN Ia). We present optical light curves and spectra of SN 2006bt which demonstrate the peculiar nature of this object. SN 2006bt has broad, slowly declining light curves indicative of a hot, high-luminosity SN, but lacks a prominent second maximum in the i band as do low-luminosity SNe Ia. Its spectra are similar to those of low-luminosity SNe Ia, containing features that are only present in cool SN photospheres. Light-curve fitting methods suggest that SN 2006bt is reddened by a significant amount of dust; however, it occurred in the outskirts of its early-type host galaxy and has no strong Na D absorption in any of its spectra, suggesting a negligible amount of host-galaxy dust absorption. C II is possibly detected in our pre-maximum spectra, but at a much lower velocity than other elements. The progenitor was likely very old, being a member of the halo population of a galaxy that shows no signs of recent star formation. SNe Ia have been very successfully modeled as a one-parameter family, and this is fundamental to their use as cosmological distance indicators. SN 2006bt is a challenge to that picture, yet its relatively normal light curves allowed SN 2006bt to be included in cosmological analyses. We generate mock SN Ia data sets which indicate that contamination by similar objects will both increase the scatter of a SN Ia Hubble diagram and systematically bias measurements of cosmological parameters. However, spectra and rest-frame i-band light curves should provide a definitive way to identify and eliminate such objects.

  14. A CATALOG OF NEAR-INFRARED SPECTRA FROM TYPE Ia SUPERNOVAE

    International Nuclear Information System (INIS)

    Marion, G. H.; Wheeler, J. C.; Robinson, E. L.; Hoeflich, P.; Gerardy, C. L.; Vacca, W. D.

    2009-01-01

    We present 41 near-infrared (NIR, 0.7-2.5 μm) spectra from normal Type Ia supernovae (SNe Ia) obtained at epochs ranging from 14 days before to 75 days with respect to the maximum light date in the V band. All data were obtained at the Infrared Telescope Facility using the SpeX instrument. We identify many spectral features, measure the Doppler velocities, and discuss the chemical distribution of explosion products in SNe Ia. We describe procedures for smoothing data, fitting continua, and measuring absorption features to ensure consistency for measurement and analysis. This sample provides the first opportunity to examine and compare a large number of SNe Ia in this wavelength region. NIR data are a rich source of information about explosion products whose signatures are blended or obscured in other spectral regions and NIR observations probe a greater radial depth than optical wavelengths. We analyze similarities and differences in the spectra and we show that the progressive development of spectral features for normal SNe Ia in the NIR is consistent with time. We confirm the presence of O I, Mg II, Ca II, Si II, Fe II, and Co II in these SNe. Possible identifications are made for S I, Si III, Mn II, and Fe III. There is no evidence in these data for H I, He I, C I, or C II. As the explosion products expand and cool, progressively deeper layers are revealed. Thus, a time sequence of spectra examines the chemical structure and provides direct evidence of the physical properties of SNe Ia from the outer layers to deep inside the SN. Measured Doppler velocities indicate that burning products in SNe Ia are distributed in distinct layers with no large-scale mixing. Carbon is not detected in these data, in agreement with previous results with NIR data establishing very low limits on carbon abundance in SNe Ia. Carbon burning products, O and Mg, are plentiful in the outer layers suggesting that the entire progenitor is burned in the explosion. The data provide a

  15. ON THE PROGENITORS OF SUPER-CHANDRASEKHAR MASS TYPE Ia SUPERNOVAE

    International Nuclear Information System (INIS)

    Chen Wencong; Li Xiangdong

    2009-01-01

    Type Ia supernovae (SNe Ia) can be used as the standard candle to determine the cosmological distances because they are thought to have a uniform fuel amount. Recent observations of several overluminous SNe Ia suggest that the white dwarf masses at supernova explosion may significantly exceed the canonical Chandrasekhar mass limit. These massive white dwarfs may be supported by rapid differential rotation. Based on a single-degenerate model and the assumption that the white dwarf would differentially rotate when the accretion rate M-dot>3 x 10 -7 M-odot yr -1 , we have calculated the evolutions of close binaries consisting of a white dwarf and a normal companion. To include the effect of rotation, we introduce an effective mass M eff for white dwarfs. For the donor stars with two different metallicities Z = 0.02 and 0.001, we present the distribution of the initial donor star masses and the orbital periods of the progenitors of super-Chandrasekhar mass SNe Ia. The calculation results indicate that, for an initial massive white dwarf of 1.2 M sun , a considerable fraction of SNe Ia may result from super-Chandrasekhar mass white dwarfs, but very massive (> 1.7 M sun ) white dwarfs are difficult to form, and none of them could be found in old populations. However, super-Chandrasekhar mass SNe Ia are very rare when the initial mass of white dwarfs is 1.0 M sun . Additionally, SNe Ia in low metallicity environment are more likely to be homogeneous.

  16. Reddened, Redshifted, or Intrinsically Red? Understanding Near-ultraviolet Colors of Type Ia Supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Peter J.; Landez, Nancy J. [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Texas A. and M. University, Department of Physics and Astronomy, 4242 TAMU, College Station, TX 77843 (United States); Milne, Peter A. [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Stritzinger, Maximilian D., E-mail: pbrown@physics.tamu.edu [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark)

    2017-02-20

    The intrinsic colors of Type Ia supernovae (SNe Ia) are important to understanding their use as cosmological standard candles. Understanding the effects of reddening and redshift on the observed colors are complicated and dependent on the intrinsic spectrum, the filter curves, and the wavelength dependence of reddening. We present ultraviolet and optical data of a growing sample of SNe Ia observed with the Ultraviolet/Optical Telescope on the Swift spacecraft and use this sample to re-examine the near-UV (NUV) colors of SNe Ia. We find that a small amount of reddening ( E ( B − V ) = 0.2 mag) could account for the difference between groups designated as NUV-blue and NUV-red, and a moderate amount of reddening ( E ( B − V ) = 0.5 mag) could account for the whole NUV-optical differences. The reddening scenario, however, is inconsistent with the mid-UV colors and color evolution. The effect of redshift alone only accounts for part of the variation. Using a spectral template of SN2011fe, we can forward model the effects of redshift and reddening and directly compare those with the observed colors. We find that some SNe are consistent with reddened versions of SN2011fe, but most SNe Ia are much redder in the uvw 1 − v color than SN2011fe reddened to the same b − v color. The absolute magnitudes show that two out of five NUV-blue SNe Ia are blue because their near-UV luminosity is high, and the other three are optically fainter. We also show that SN 2011fe is not a “normal” SN Ia in the UV, but has colors placing it at the blue extreme of our sample.

  17. The Host Galaxies of Type Ia Supernovae Discovered by the Palomar Transient Factory

    Science.gov (United States)

    Pan, Y.-C.; Sullivan, M.; McGuire, K.; Hook, I. M.; Nugent, P. E.; Howell, D. A.; Arcavi, I.; Botyanszki, J.; Cenko, Stephen Bradley; DeRose, J.

    2013-01-01

    We present spectroscopic observations of the host galaxies of 82 low-redshift type Ia supernovae (SNe Ia) discovered by the Palomar Transient Factory (PTF). We determine star-formation rates, gas-phase stellar metallicities, and stellar masses and ages of these objects. As expected, strong correlations between the SN Ia light-curve width (stretch) and the host age mass metallicity are found: fainter, faster-declining events tend to be hosted by older massive metal-rich galaxies. There is some evidence that redder SNe Ia explode in higher metallicity galaxies, but we found no relation between the SN colour and host galaxy extinction based on the Balmer decrement, suggesting that the colour variation of these SNe does not primarily arise from this source. SNe Ia in higher-mass metallicity galaxies also appear brighter after stretch colour corrections than their counterparts in lower mass hosts, and the stronger correlation is with gas-phase metallicity suggesting this may be the more important variable. We also compared the host stellar mass distribution to that in galaxy targeted SN surveys and the high-redshift untargeted Supernova Legacy Survey (SNLS). SNLS has many more low mass galaxies, while the targeted searches have fewer. This can be explained by an evolution in the galaxy stellar mass function, coupled with a SN delay-time distribution proportional to t1. Finally, we found no significant difference in the mass--metallicity relation of our SN Ia hosts compared to field galaxies, suggesting any metallicity effect on the SN Ia rate is small.

  18. Improved Distances to Type Ia Supernovae withMulticolor Light Curve Shapes: MLCS2k2

    Energy Technology Data Exchange (ETDEWEB)

    Jha, Saurabh; /KIPAC, Menlo Park; Riess, Adam G.; /Baltimore, Space Telescope Sci.; Kirshner, Robert P.; /Harvard-Smithsonian Ctr. Astrophys.

    2007-01-05

    We present an updated version of the Multicolor Light Curve Shape method to measure distances to type Ia supernovae (SN Ia), incorporating new procedures for K-correction and extinction corrections. We also develop a simple model to disentangle intrinsic color variations and reddening by dust, and expand the method to incorporate U-band light curves and to more easily accommodate prior constraints on any of the model parameters. We apply this method to 133 nearby SN Ia, including 95 objects in the Hubble flow (cz {ge} 2500 km s{sup -1}), which give an intrinsic dispersion of less than 7% in distance. The Hubble flow sample, which is of critical importance to all cosmological uses of SN Ia, is the largest ever presented with homogeneous distances. We find the Hubble flow supernovae with H{sub 0}d{sub SN} {ge} 7400 km s{sup -1} yield an expansion rate that is 6.5 {+-} 1.8% lower than the rate determined from supernovae within that distance, and this can have a large effect on measurements of the dark energy equation of state with SN Ia. Peculiar velocities of SN Ia host galaxies in the rest frame of the Local Group are consistent with the dipole measured in the Cosmic Microwave Background. Direct fits of SN Ia that are significantly reddened by dust in their host galaxies suggest their mean extinction law may be described by R{sub V} {approx_equal} 2.7, but optical colors alone provide weak constraints on R{sub V}.

  19. Evidence for a Sub-Chandrasekhar-mass Type Ia Supernova in the Ursa Minor Dwarf Galaxy

    Science.gov (United States)

    McWilliam, Andrew; Piro, Anthony L.; Badenes, Carles; Bravo, Eduardo

    2018-04-01

    A long-standing problem is identifying the elusive progenitors of Type Ia supernovae (SNe Ia), which can roughly be split into Chandraksekhar and sub-Chandrasekhar-mass events. An important difference between these two cases is the nucleosynthetic yield, which is altered by the increased neutron excess in Chandrasekhar progenitors due to their pre-explosion simmering and high central density. Based on these arguments, we show that the chemical composition of the most metal-rich star in the Ursa Minor dwarf galaxy, COS 171, is dominated by nucleosynthesis from a low-metallicity, low-mass, sub-Chandrasekhar-mass SN Ia. Key diagnostic abundance ratios include Mn/Fe and Ni/Fe, which could not have been produced by a Chandrasekhar-mass SN Ia. Large deficiencies of Ni/Fe, Cu/Fe and Zn/Fe also suggest the absence of alpha-rich freeze-out nucleosynthesis, favoring low-mass white dwarf progenitors of SNe Ia, near 0.95 M ⊙, from comparisons to numerical detonation models. We also compare Mn/Fe and Ni/Fe ratios to the recent yields predicted by Shen et al., finding consistent results. To explain the [Fe/H] at ‑1.35 dex for COS 171 would require dilution of the SN Ia ejecta with ∼104 M ⊙ of material, which is expected for an SN remnant expanding into a warm interstellar medium with n ∼ 1 cm‑3. In the future, finding more stars with the unique chemical signatures we highlight here will be important for constraining the rate and environments of sub-Chandrasekhar SNe Ia.

  20. Discovering the Nature of Dark Energy: Towards Better Distances from Type Ia Supernovae -- Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Filippenko, Alexei Vladimir [Univ. of California, Berkeley, CA (United States)

    2014-05-09

    Type Ia supernovae (SNe Ia; exploding white-dwarf stars) were the key to the Nobel-worthy 1998 discovery and subsequent verification that the expansion of the Universe is accelerating, driven by the effects of dark energy. Understanding the nature of this mysterious, yet dominant, component of the Universe is at the forefront of research in cosmology and fundamental physics. SNe Ia will continue to play a leading role in this enterprise, providing precise cosmological distances that improve constraints on the nature of dark energy. However, for this effort to succeed, we need to more thoroughly understand relatively nearby SNe Ia, because our conclusions come only from comparisons between them and distant (high-redshift) SNe Ia. Thus, detailed studies of relatively nearby SNe Ia are the focus of this research program. Many interesting results were obtained during the course of this project; these were published in 32 refereed research papers that acknowledged the grant. A major accomplishment was the publication of supernova (SN) rates derived from about a decade of operation of the Lick Observatory Supernova Search (LOSS) with the 0.76-meter Katzman Automatic Imaging Telescope (KAIT). We have determined the most accurate rates for SNe of different types in large, nearby galaxies in the present-day Universe, and these can be compared with SN rates far away (and hence long ago in the past) to set constraints on the types of stars that explode. Another major accomplishment was the publication of the light curves (brightness vs. time) of 165 SNe Ia, along with optical spectroscopy of many of these SNe as well as other SNe Ia, providing an extensive, homogeneous database for detailed studies. We have conducted intensive investigations of a number of individual SNe Ia, including quite unusual examples that allow us to probe the entire range of SN explosions and provide unique insights into these objects and the stars before they explode. My team's studies have also

  1. Natural History of Gutter-Related Type Ia Endoleaks after Snorkel/Chimney EVAR

    Science.gov (United States)

    Ullery, Brant W.; Tran, Kenneth; Itoga, Nathan K.; Dalman, Ronald L.; Lee, Jason T.

    2018-01-01

    Objective Alternative endovascular strategies utilizing parallel or snorkel/chimney (ch-EVAR) techniques have been developed to address the lack of widespread availability and manufacturing limitations with branched/fenestrated aortic devices for the treatment of complex abdominal aortic aneurysms. Despite high technical success and mid-term patency of snorkel stent configurations, concerns remain regarding the perceived increased incidence of early gutter-related type Ia endoleaks. We aimed to evaluate the incidence and natural history of gutter-related type Ia endoleaks following ch-EVAR. Methods Review of medical records and available imaging studies, including completion angiography and serial computed tomographic angiography, was performed for all patients undergoing ch-EVAR at our institution between September 2009 and January 2015. Only procedures involving ≥1 renal artery with or without visceral snorkel stents were included. Primary outcomes of the study were presence and persistence or resolution of early gutter-related type Ia endoleak. Secondary outcomes included aneurysm sac shrinkage and need for secondary intervention related to the presence of type Ia gutter endoleak. Results Sixty patients (mean age, 75.8 ± 7.6 years; male, 70.0%) underwent ch-EVAR with a total of 111 snorkel stents (97 renal [33 bilateral renal], 12 SMA, 2 celiac). A median of 2 (range, 1-4) snorkel stents were placed per patient. Early gutter-related type Ia endoleaks were noted on 30.0% (n=18) of initial postoperative imaging studies. Follow-up imaging revealed spontaneous resolution of these gutter endoleaks in 47.3% and 71.8% of patients at 6- and 12 months post-procedure, respectively. Long-term anticoagulation, degree of oversizing, stent type and diameter, and other clinical/anatomic variables were not significantly associated with presence of gutter endoleaks. Two patients (3.3%) required secondary intervention related to persistent gutter endoleak. At a mean radiologic

  2. THE OXYGEN FEATURES IN TYPE Ia SUPERNOVAE AND IMPLICATIONS FOR THE NATURE OF THERMONUCLEAR EXPLOSIONS

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Xulin; Wang, Xiaofeng; Sai, Hanna; Huang, Fang; Rui, Liming [Physics Department and Tsinghua Center for Astrophysics, Tsinghua University, Beijing, 100084 (China); Maeda, Keiichi [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Wang, Lifan [Mitchell Institute for Fundamental Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); Zhang, Jujia [Yunnan Observatories, Chinese Academy of Sciences, Kunming, 650216 (China); Zhang, Tianmeng, E-mail: wang_xf@mail.tsinghua.edu.cn, E-mail: zhaoxl11@mails.tsinghua.edu.cn, E-mail: keiichi.maeda@kusastro.kyoto-u.ac.jp [National Astronomical Observatory of China, Chinese Academy of Sciences, Beijing, 100012 (China)

    2016-08-01

    The absorption feature O i λ 7773 is an important spectral indicator for type Ia supernovae (SNe Ia) that can be used to trace the unburned material in outer layers of the exploding white dwarf (WD). In this work, we use a large sample of SNe Ia to examine this absorption at early phases (i.e., 13 day ≲ t ≲ 7 day) and make comparisons with the absorption features of Si ii λ 6355 and the Ca ii near-infrared triplet. We show that for a subgroup of spectroscopically normal SNe with normal photospheric velocities (i.e., v {sub si} ≲ 12,500 km s{sup 1} at optical maximum), the line strength of the high velocity feature (HVF) of O i is inversely correlated with that of Si ii (or Ca ii), and this feature also shows a negative correlation with the luminosity of SNe Ia. This finding, together with other features we find for the O i HVF, reveal that for this subgroup of SNe Ia, explosive oxygen burning occurs in the outermost layer of the SN. Differences in the oxygen burning could lead to the observed diversity, which is in remarkable agreement with the popular delayed-detonation model of Chandrasekhar mass WDs.

  3. PHOTOMETRIC TYPE Ia SUPERNOVA CANDIDATES FROM THE THREE-YEAR SDSS-II SN SURVEY DATA

    International Nuclear Information System (INIS)

    Sako, Masao; Connolly, Brian; Gladney, Larry; Bassett, Bruce; Dilday, Benjamin; Cambell, Heather; Lampeitl, Hubert; Nichol, Robert C.; Frieman, Joshua A.; Kessler, Richard; Marriner, John; Miquel, Ramon; Schneider, Donald P.; Smith, Mathew; Sollerman, Jesper

    2011-01-01

    We analyze the three-year Sloan Digital Sky Survey II (SDSS-II) Supernova (SN) Survey data and identify a sample of 1070 photometric Type Ia supernova (SN Ia) candidates based on their multiband light curve data. This sample consists of SN candidates with no spectroscopic confirmation, with a subset of 210 candidates having spectroscopic redshifts of their host galaxies measured while the remaining 860 candidates are purely photometric in their identification. We describe a method for estimating the efficiency and purity of photometric SN Ia classification when spectroscopic confirmation of only a limited sample is available, and demonstrate that SN Ia candidates from SDSS-II can be identified photometrically with ∼91% efficiency and with a contamination of ∼6%. Although this is the largest uniform sample of SN candidates to date for studying photometric identification, we find that a larger spectroscopic sample of contaminating sources is required to obtain a better characterization of the background events. A Hubble diagram using SN candidates with no spectroscopic confirmation, but with host galaxy spectroscopic redshifts, yields a distance modulus dispersion that is only ∼20%-40% larger than that of the spectroscopically confirmed SN Ia sample alone with no significant bias. A Hubble diagram with purely photometric classification and redshift-distance measurements, however, exhibits biases that require further investigation for precision cosmology.

  4. A Precision Photometric Comparison between SDSS-II and CSP Type Ia Supernova Data

    DEFF Research Database (Denmark)

    Mosher, J.; Sako, M.; Corlies, L.

    2012-01-01

    Consistency between Carnegie Supernova Project (CSP) and SDSS-II Supernova Survey ugri measurements has been evaluated by comparing Sloan Digital Sky Survey (SDSS) and CSP photometry for nine spectroscopically confirmed Type Ia supernova observed contemporaneously by both programs. The CSP data...

  5. THE PROGENITORS OF TYPE Ia SUPERNOVAE. I. ARE THEY SUPERSOFT SOURCES?

    International Nuclear Information System (INIS)

    Di Stefano, R.

    2010-01-01

    In a canonical model, the progenitors of Type Ia supernovae (SNe Ia) are accreting, nuclear-burning white dwarfs (NBWDs), which explode when the white dwarf reaches the Chandrasekhar mass, M C . Such massive NBWDs are hot (kT ∼ 100 eV), luminous (L ∼ 10 38 erg s -1 ), and are potentially observable as luminous supersoft X-ray sources (SSSs). During the past several years, surveys for soft X-ray sources in external galaxies have been conducted. This paper shows that the results falsify the hypothesis that a large fraction of progenitors are NBWDs which are presently observable as SSSs. The data also place limits on sub-M C models. While SN Ia progenitors may pass through one or more phases of SSS activity, these phases are far shorter than the time needed to accrete most of the matter that brings them close to M C .

  6. Exploring the spectroscopic diversity of type Ia supernovae with Deep Learning and Unsupervised Clustering

    Science.gov (United States)

    Ishida, Emille E. O.; Sasdelli, Michele; Vilalta, Ricardo; Aguena, Michel; Busti, Vinicius C.; Camacho, Hugo; Trindade, Arlindo M. M.; Gieseke, Fabian; de Souza, Rafael S.; Fantaye, Yabebal T.; Mazzali, Paolo A.

    2017-06-01

    The existence of multiple subclasses of type Ia supernovae (SNeIa) has been the subject of great debate in the last decade. In this work, we show how machine learning tools facilitate identification of subtypes of SNe Ia. Using Deep Learning for dimensionality reduction, we were capable of performing such identification in a parameter space of significantly lower dimension than its principal component analysis counterpart. This is evidence that the progenitor system and the explosion mechanism can be described with a small number of initial physical parameters. All tools used here are publicly available in the Python package DRACULA (Dimensionality Reduction And Clustering for Unsupervised Learning in Astronomy) and can be found within COINtoolbox (https://github.com/COINtoolbox/DRACULA).

  7. Observational Evidence for High Neutronization in Supernova Remnants: Implications for Type Ia Supernova Progenitors

    Energy Technology Data Exchange (ETDEWEB)

    Martínez-Rodríguez, Héctor; Badenes, Carles; Andrews, Brett [Department of Physics and Astronomy and Pittsburgh Particle Physics, Astrophysics and Cosmology Center (PITT PACC), University of Pittsburgh, 3941 O’Hara Street, Pittsburgh, PA 15260 (United States); Yamaguchi, Hiroya [NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States); Bravo, Eduardo [E.T.S. Arquitectura del Vallès, Universitat Politècnica de Catalunya, Carrer Pere Serra 1-15, E-08173 Sant Cugat del Vallès (Spain); Timmes, F. X. [The Joint Institute for Nuclear Astrophysics (United States); Miles, Broxton J.; Townsley, Dean M. [Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL (United States); Piro, Anthony L. [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Mori, Hideyuki [CRESST and X-ray Astrophysics Laboratory, NASA Goddard Space Flight Center, Code 602, Greenbelt, MD 20771 (United States); Park, Sangwook, E-mail: hector.mr@pitt.edu [Department of Physics, University of Texas at Arlington, Box 19059, Arlington, TX 76019 (United States)

    2017-07-01

    The physical process whereby a carbon–oxygen white dwarf explodes as a Type Ia supernova (SN Ia) remains highly uncertain. The degree of neutronization in SN Ia ejecta holds clues to this process because it depends on the mass and the metallicity of the stellar progenitor, and on the thermodynamic history prior to the explosion. We report on a new method to determine ejecta neutronization using Ca and S lines in the X-ray spectra of Type Ia supernova remnants (SNRs). Applying this method to Suzaku data of Tycho, Kepler , 3C 397, and G337.2−0.7 in the Milky Way, and N103B in the Large Magellanic Cloud, we find that the neutronization of the ejecta in N103B is comparable to that of Tycho and Kepler , which suggests that progenitor metallicity is not the only source of neutronization in SNe Ia. We then use a grid of SN Ia explosion models to infer the metallicities of the stellar progenitors of our SNRs. The implied metallicities of 3C 397, G337.2−0.7, and N103B are major outliers compared to the local stellar metallicity distribution functions, indicating that progenitor metallicity can be ruled out as the origin of neutronization for these SNRs. Although the relationship between ejecta neutronization and equivalent progenitor metallicity is subject to uncertainties stemming from the {sup 12}C + {sup 16}O reaction rate, which affects the Ca/S mass ratio, our main results are not sensitive to these details.

  8. Genetics Home Reference: hereditary sensory neuropathy type IA

    Science.gov (United States)

    ... Houlden H, King R, Blake J, Groves M, Love S, Woodward C, Hammans S, Nicoll J, Lennox G, O'Donovan DG, Gabriel C, Thomas PK, Reilly MM. Clinical, pathological and genetic characterization of hereditary sensory and autonomic neuropathy type 1 (HSAN I). Brain. 2006 Feb;129(Pt 2):411-25. Epub ...

  9. IMPROVED DARK ENERGY CONSTRAINTS FROM ∼100 NEW CfA SUPERNOVA TYPE Ia LIGHT CURVES

    International Nuclear Information System (INIS)

    Hicken, Malcolm; Challis, Peter; Kirshner, Robert P.; Wood-Vasey, W. Michael; Blondin, Stephane; Jha, Saurabh; Kelly, Patrick L.; Rest, Armin

    2009-01-01

    We combine the CfA3 supernovae Type Ia (SN Ia) sample with samples from the literature to calculate improved constraints on the dark energy equation of state parameter, w. The CfA3 sample is added to the Union set of Kowalski et al. to form the Constitution set and, combined with a BAO prior, produces 1 + w = 0.013 +0.066 -0.068 (0.11 syst), consistent with the cosmological constant. The CfA3 addition makes the cosmologically useful sample of nearby SN Ia between 2.6 and 2.9 times larger than before, reducing the statistical uncertainty to the point where systematics play the largest role. We use four light-curve fitters to test for systematic differences: SALT, SALT2, MLCS2k2 (R V = 3.1), and MLCS2k2 (R V = 1.7). SALT produces high-redshift Hubble residuals with systematic trends versus color and larger scatter than MLCS2k2. MLCS2k2 overestimates the intrinsic luminosity of SN Ia with 0.7 V = 3.1 overestimates host-galaxy extinction while R V ∼ 1.7 does not. Our investigation is consistent with no Hubble bubble. We also find that, after light-curve correction, SN Ia in Scd/Sd/Irr hosts are intrinsically fainter than those in E/S0 hosts by 2σ, suggesting that they may come from different populations. We also find that SN Ia in Scd/Sd/Irr hosts have low scatter (0.1 mag) and reddening. Current systematic errors can be reduced by improving SN Ia photometric accuracy, by including the CfA3 sample to retrain light-curve fitters, by combining optical SN Ia photometry with near-infrared photometry to understand host-galaxy extinction, and by determining if different environments give rise to different intrinsic SN Ia luminosity after correction for light-curve shape and color.

  10. Aortic Curvature Is a Predictor of Late Type Ia Endoleak and Migration After Endovascular Aneurysm Repair.

    Science.gov (United States)

    Schuurmann, Richte C L; van Noort, Kim; Overeem, Simon P; Ouriel, Kenneth; Jordan, William D; Muhs, Bart E; 't Mannetje, Yannick; Reijnen, Michel; Fioole, Bram; Ünlü, Çağdaş; Brummel, Peter; de Vries, Jean-Paul P M

    2017-06-01

    To evaluate the association between aortic curvature and other preoperative anatomical characteristics and late (>1 year) type Ia endoleak and endograft migration in endovascular aneurysm repair (EVAR) patients. Eight high-volume EVAR centers contributed 116 EVAR patients (mean age 81±7 years; 103 men) to the study: 36 patients (mean age 82±7 years; 31 men) with endograft migration and/or type Ia endoleak diagnosed >1 year after the initial EVAR and 80 controls without early or late complications. Aortic curvature was calculated from the preoperative computed tomography scan as the maximum and average curvature over 5 predefined aortic segments: the entire infrarenal aortic neck, aneurysm sac, and the suprarenal, juxtarenal, and infrarenal aorta. Other morphological characteristics included neck length, neck diameter, mural neck calcification and thrombus, suprarenal and infrarenal angulation, and largest aneurysm sac diameter. Independent risk factors were identified using backward stepwise logistic regression. Relevant cutoff values for each of the variables in the final regression model were determined with the receiver operator characteristic curve. Logistic regression identified maximum curvature over the length of the aneurysm sac (>47 m -1 ; p=0.023), largest aneurysm sac diameter (>56 mm; p=0.028), and mural neck thrombus (>11° circumference; pIa endoleak. Aortic curvature is a predictor for late type Ia endoleak and endograft migration after EVAR. These findings suggest that aortic curvature is a better parameter than angulation to predict post-EVAR failure and should be included as a hostile neck parameter.

  11. An early-time infrared and optical study of the type Ia supernovae SN 1994D and 1991T

    NARCIS (Netherlands)

    Meikle, WPS; Cumming, RJ; Geballe, TR; Lewis, [No Value; Walton, NA; Balcells, M; Cimatti, A; Croom, SM; Dhillon, VS; Economou, F; Jenkins, CR; Knapen, JH; Lucey, [No Value; Meadows, VS; Morris, PW; PerezFournon, [No Value; Shanks, T; Smith, LJ; Tanvir, NR; Veilleux, S; Vilchez, J; Wall, JV

    1996-01-01

    We present early-time infrared (IR) and optical spectroscopy, and optical photometry, of the Type Ia supernova 1994D. These observations provide the most complete optical-IR spectral coverage ever achieved for a Type Ia at this phase. Optical and IR spectra were obtained as early as 9 d before

  12. A reddening-free method to estimate the 56Ni mass of Type Ia supernovae

    Science.gov (United States)

    Dhawan, S.; Leibundgut, B.; Spyromilio, J.; Blondin, S.

    2016-04-01

    The increase in the number of Type Ia supernovae (SNe Ia) has demonstrated that the population shows greater diversity than has been assumed in the past. The reasons (e.g. parent population, explosion mechanism) for this diversity remain largely unknown. We investigated a sample of SNe Ia near-infrared light curves and correlated the phase of the second maximum with the bolometric peak luminosity. The peak bolometric luminosity is related to the time of the second maximum (relative to the B light curve maximum) as follows: Lmax(1043 erg s-1) = (0.039 ± 0.004) × t2(J)(days) + (0.013 ± 0.106). 56Ni masses can be derived from the peak luminosity based on Arnett's rule, which states that the luminosity at maximum is equal to the instantaneous energy generated by the nickel decay. We checked this assumption against recent radiative-transfer calculations of Chandrasekhar-mass delayed detonation models and find this assumption is valid to within 10% in recent radiative-transfer calculations of Chandrasekhar-mass delayed detonation models. The Lmax vs. t2 relation is applied to a sample of 40 additional SNe Ia with significant reddening (E(B - V) > 0.1 mag), and a reddening-free bolometric luminosity function of SNe Ia is established. The method is tested with the 56Ni mass measurement from the direct observation of γ-rays in the heavily absorbed SN 2014J and found to be fully consistent. Super-Chandrasekhar-mass explosions, in particular SN 2007if, do not follow the relations between peak luminosity and second IR maximum. This may point to an additional energy source contributing at maximum light. The luminosity function of SNe Ia is constructed and is shown to be asymmetric with a tail of low-luminosity objects and a rather sharp high-luminosity cutoff, although it might be influenced by selection effects.

  13. UV–OPTICAL OBSERVATION OF TYPE Ia SUPERNOVA SN 2013dy IN NGC 7250

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, Qian; Zhang, Ju-Jia; Chang, Liang; Yi, Wei-Min; Wang, Chuan-Jun; Xin, Yu-Xin; Wang, Jian-Guo; Lun, Bao-Li; Zhang, Xi-Liang; Fan, Yu-Feng; Zheng, Xiang-Ming; Bai, Jin-Ming [Yunnan Observatories (YNAO), Chinese Academy of Sciences, Kunming 650011 (China); Wang, Xiao-Feng; Huang, Fan; Zhao, Xu-Lin [Physics Department and Tsinghua Center for Astrophysics (THCA), Tsinghua University, Beijing 100084 (China); Zhang, Tian-Meng [National Astronomical Observatories of China (NAOC), Chinese Academy of Sciences, Beijing 100012 (China); Liu, Zheng-Wei [Argelander-Institut für Astronomie, Auf dem Hügel 71, D-53121, Bonn (Germany); Brown, Peter J., E-mail: jujia@ynao.ac.cn [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Texas A. and M. University, Department of Physics and Astronomy, 4242 TAMU, College Station, TX 77843 (United States)

    2016-05-01

    Extensive and independent observations of Type Ia supernova (SN Ia) SN 2013dy are presented, including a larger set of UBVRI photometry and optical spectra from a few days before the peak brightness to ∼ 200 days after explosion, and ultraviolet (UV) photometry spanning from t  ≈ –10 days to t  ≈ +15 days refers to the B band maximum. The peak brightness (i.e., M {sub B} = –19.65 ± 0.40 mag; L {sub max} = [1.95 ± 0.55] × 10{sup 43} erg s{sup −1}) and the mass of synthesized {sup 56}Ni (i.e., M ({sup 56}Ni) = 0.90 ± 0.26 M {sub ⊙}) are calculated, and they conform to the expectation for an SN Ia with a slow decline rate (i.e., Δ m {sub 15}( B ) = 0.90 ± 0.03 mag). However, the near infrared (NIR) brightness of this SN (i.e., M {sub H} = –17.33 ± 0.30 mag) is at least 1.0 mag fainter than usual. Besides, spectroscopy classification reveals that SN 2013dy resides on the border of “core normal” and “shallow silicon” subclasses in the Branch et al. classification scheme, or on the border of the “normal velocity” SNe Ia and 91T/99aa-like events in the Wang et al. system. These suggest that SN 2013dy is a slow-declining SN Ia located on the transitional region of nominal spectroscopic subclasses and might not be a typical normal sample of SNe Ia.

  14. ON THE LIRA LAW AND THE NATURE OF EXTINCTION TOWARD TYPE Ia SUPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Foerster, Francisco; Gonzalez-Gaitan, Santiago [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Folatelli, Gaston [Kavli Institute for the Physics and Mathematics of the Universe, Todai Institutes for Advanced Study (TODIAS), University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Morrell, Nidia [Las Campanas Observatory, Carnegie Observatories, Casilla 601, La Serena (Chile)

    2013-07-20

    We have studied the relation between the color evolution of Type Ia supernovae (SNe Ia) from maximum light to the Lira law regime and the presence of narrow absorption features. Based on a nearby sample of 89 SNe Ia, we have found that the rate of change of B - V colors at late phases (between 35 and 80 days after maximum) varies significantly among different SNe Ia. At maximum light, faster Lira law B - V decliners have significantly higher equivalent widths of blended Na I D1 and D2 narrow absorption lines, redder colors, and lower R{sub V} reddening laws. We do not find faster Lira law B - V decliners to have a strong preference for younger galaxy environments, where higher interstellar material (ISM) column densities would be expected. We interpret these results as evidence for the presence of circumstellar material. The differences in colors and reddening laws found at maximum light are also present 55 days afterward, but unlike the colors at maximum they show a significant variation among different host galaxy morphological types. This suggests that the effect of ISM on the colors is more apparent at late times. Finally, we discuss how the transversal expansion of the ejecta in an inhomogeneous ISM could mimic some of these findings.

  15. Type Ia Supernova Modeling with Spectrophotometric Data from the Nearby Supernova Factory

    Science.gov (United States)

    Myers Saunders, Clare; Nearby Supernova Factory

    2018-01-01

    We present a set of empirical models for Type Ia Supernovae constructed using data from the Nearby Supernova Factory. Starting with the spectrophotometric data from this survey, Gaussian Processes and Expectation Maximization Factor Analysis were used to build a series of spectral time series templates that are combined linearly to form a model that can be fit to the lightcurves or spectra of a Type Ia supernova. We present a less-complex model that is tuned to minimize dispersion in the supernova corrected magnitudes and a more-complex model that maximizes the amount of SNIa spectral diversity captured. We show methods for lowering the amount of dispersion in corrected magnitudes using these models, thus increasing the precision of SNe Ia as a cosmological tool and decreasing the possibility for systematic uncertainties. The models are compared with other current methods of using SNe Ia for cosmology. We demonstrate their performance on photometric data, or combinations of spectral and photometric data, and their predicted utility for upcoming surveys such as LSST and WFIRST.

  16. An unusual white dwarf star may be a surviving remnant of a subluminous Type Ia supernova.

    Science.gov (United States)

    Vennes, S; Nemeth, P; Kawka, A; Thorstensen, J R; Khalack, V; Ferrario, L; Alper, E H

    2017-08-18

    Subluminous Type Ia supernovae, such as the Type Iax-class prototype SN 2002cx, are described by a variety of models such as the failed detonation and partial deflagration of an accreting carbon-oxygen white dwarf star or the explosion of an accreting, hybrid carbon-oxygen-neon core. These models predict that bound remnants survive such events with, according to some simulations, a high kick velocity. We report the discovery of a high proper motion, low-mass white dwarf (LP 40-365) that travels at a velocity greater than the Galactic escape velocity and whose peculiar atmosphere is dominated by intermediate-mass elements. Strong evidence indicates that this partially burnt remnant was ejected following a subluminous Type Ia supernova event. This supports the viability of single-degenerate supernova progenitors. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  17. WHITE DWARF/M DWARF BINARIES AS SINGLE DEGENERATE PROGENITORS OF TYPE Ia SUPERNOVAE

    International Nuclear Information System (INIS)

    Wheeler, J. Craig

    2012-01-01

    Limits on the companions of white dwarfs in the single-degenerate scenario for the origin of Type Ia supernovae (SNe Ia) have gotten increasingly tight, yet igniting a nearly Chandrasekhar mass C/O white dwarf from a condition of near hydrostatic equilibrium provides compelling agreement with observed spectral evolution. The only type of non-degenerate stars that survive the tight limits, M V ∼> 8.4 on the SN Ia in SNR 0509-67.5 and M V ∼> 9.5 in the remnant of SN 1572, are M dwarfs. While M dwarfs are observed in cataclysmic variables, they have special properties that have not been considered in most work on the progenitors of SNe Ia: they have small but finite magnetic fields and they flare frequently. These properties are explored in the context of SN Ia progenitors. White dwarf/M dwarf pairs may be sufficiently plentiful to provide, in principle, an adequate rate of explosions even with slow orbital evolution due to magnetic braking or gravitational radiation. Even modest magnetic fields on the white dwarf and M dwarf will yield adequate torques to lock the two stars together, resulting in a slowly rotating white dwarf, with the magnetic poles pointing at one another in the orbital plane. The mass loss will be channeled by a 'magnetic bottle' connecting the two stars, landing on a concentrated polar area on the white dwarf. This enhances the effective rate of accretion compared to spherical accretion. Luminosity from accretion and hydrogen burning on the surface of the white dwarf may induce self-excited mass transfer. The combined effects of self-excited mass loss, polar accretion, and magnetic inhibition of mixing of accretion layers give possible means to beat the 'nova limit' and grow the white dwarf to the Chandrasekhar mass even at rather moderate mass accretion rates.

  18. The cosmic transparency measured with Type Ia supernovae: implications for intergalactic dust

    Science.gov (United States)

    Goobar, Ariel; Dhawan, Suhail; Scolnic, Daniel

    2018-04-01

    Observations of high-redshift Type Ia supernovae (SNe Ia) are used to study the cosmic transparency at optical wavelengths. Assuming a flat ΛCDM cosmological model based on BAO and CMB results, redshift dependent deviations of SN Ia distances are used to constrain mechanisms that would dim light. The analysis is based on the most recent Pantheon SN compilation, for which there is a 0.03± 0.01 {(stat)} mag discrepancy in the distant supernova distance moduli relative to the ΛCDM model anchored by supernovae at z measurements can be modeled with a cosmic dust density Ω _IGM^dust = 8 \\cdot 10^{-5} (1+z)^{-1}, corresponding to an average attenuation of 2 . 10-5 mag Mpc-1 in V-band. Forthcoming SN Ia studies may provide a definitive measurement of the IGM dust properties, while still providing an unbiased estimate of cosmological parameters by introducing additional parameters in the global fits to the observations.

  19. Recent development and gene therapy for glycogen storage disease type Ia.

    Science.gov (United States)

    Chou, Janice Y; Kim, Goo-Young; Cho, Jun-Ho

    2017-09-01

    Glycogen storage disease type Ia (GSD-Ia) is an autosomal recessive metabolic disorder caused by a deficiency in glucose-6-phosphatase-α (G6Pase-α or G6PC) that is expressed primarily in the liver, kidney, and intestine. G6Pase-α catalyzes the hydrolysis of glucose-6-phosphate (G6P) to glucose and phosphate in the terminal step of gluconeogenesis and glycogenolysis, and is a key enzyme for endogenous glucose production. The active site of G6Pase-α is inside the endoplasmic reticulum (ER) lumen. For catalysis, the substrate G6P must be translocated from the cytoplasm into the ER lumen by a G6P transporter (G6PT). The functional coupling of G6Pase-α and G6PT maintains interprandial glucose homeostasis. Dietary therapies for GSD-Ia are available, but cannot prevent the long-term complication of hepatocellular adenoma that may undergo malignant transformation to hepatocellular carcinoma. Animal models of GSD-Ia are now available and are being exploited to both delineate the disease more precisely and develop new treatment approaches, including gene therapy.

  20. Characterization and pathogenesis of anemia in glycogen storage disease type Ia and Ib.

    Science.gov (United States)

    Wang, David Q; Carreras, Caroline T; Fiske, Laurie M; Austin, Stephanie; Boree, Danielle; Kishnani, Priya S; Weinstein, David A

    2012-09-01

    The aim of this study was to characterize the frequency and causes of anemia in glycogen storage disease type I. Hematologic data and iron studies were available from 202 subjects (163 with glycogen storage disease Ia and 39 with glycogen storage disease Ib). Anemia was defined as hemoglobin concentrations less than the 5th percentile for age and gender; severe anemia was defined as presence of a hemoglobin glycogen storage disease Ia, 68/163 patients were anemic at their last follow-up. Preadolescent patients tended to have milder anemia secondary to iron deficiency, but anemia of chronic disease predominated in adults. Severe anemia was present in 8/163 patients, of whom 75% had hepatic adenomas. The anemia improved or resolved in all 10 subjects who underwent resection of liver lesions. Anemia was present in 72% of patients with glycogen storage disease Ib, and severe anemia occurred in 16/39 patients. Anemia in patients with glycogen storage disease Ib was associated with exacerbations of glycogen storage disease enterocolitis, and there was a significant correlation between C-reactive protein and hemoglobin levels (P = 0.036). Anemia is a common manifestation of both glycogen storage disease Ia and Ib, although the pathophysiology appears to be different between these conditions. Those with severe anemia and glycogen storage disease Ia likely have hepatic adenomas, whereas glycogen storage disease enterocolitis should be considered in those with glycogen storage disease Ib.

  1. Perioperative management of benign hepatic tumors in patients with glycogen storage disease type Ia.

    Science.gov (United States)

    Oshita, Akihiko; Itamoto, Toshiyuki; Amano, Hironobu; Ohdan, Hideki; Tashiro, Hirotaka; Asahara, Toshimasa

    2008-01-01

    Glycogen storage disease type Ia (GSD-Ia; von Gierke disease) is an inherited disorder caused by glucose-6-phosphatase deficiency, and there have been some reports of hepatic tumors in patients with this disease. We report two patients with benign hepatic tumors with GSD-Ia. One is a 19-year-old man who underwent segmentectomy 4 for a focal nodular hyperplasia, and the other is a 31-year-old woman who underwent segmentectomies 3, 5, and 6 for hepatic adenomas. Two significant perioperative complications, resulting from the carbohydrate metabolic disorders, hypoglycemia and metabolic acidosis, occurred in both patients. We managed the metabolic complications successfully by administering a sufficient volume of glucose intravenously. Close perioperative monitoring of blood glucose and lactate concentrations is essential in the perioperative management of patients with GSD-Ia. The intravenous administration of glucose, starting with a smaller dose and then increasing the dose, is adequate management for lactic acidosis with or without hypoglycemia during the perioperative period.

  2. Honing Type Ia Supernovae as Distance Indicators, Exploiting Environmental Bias for H0 and w.

    Science.gov (United States)

    Rigault, Michkael

    2015-10-01

    Type Ia supernovae are excellent distance indicators and provide a uniqueprobe for measuring the expansion history of the Universe. They playkey roles both in measuring the Hubble Constant, H0, and the dark energyequation of state, w. However their exact nature remains uncertain andastrophysical dependencies have been identified and shown to significantlyaffect the measurements of H0 and w. Recently we have used a uniquesample having local host information to demonstrate that, far from beinga problem, correlations between standardized SN Ia brightnesses andproperties of their local environmental can be used to improve SNe Iaas distance indicators. These correlations can be used to both reducethe dispersion in standardized brightnesses and correct existing biases.This proposal aims to analyze both global and local properties usingUV-to-optical photometry in order to understand the source of the SNastrophysical biases found so far, and to use that knowledge to developtools with which future high-redshift SN Ia surveys can correct or exploitthese correlations. The UV data necessary to break the degeneracy betweenstellar ages and dust extinction is only accessible from space, and inthe UV, only HST can provide the angular resolution necessary to study theenvironments of nearby smooth Hubble-flow SN Ia hosts on the kpc scale.

  3. Progressive Red Shifts in the Late-Time Spectra of Type Ia Supernovae

    Science.gov (United States)

    Black, Christine; Fesen, Robert; Parrent, Jerod

    2017-01-01

    We examine the evolution of late-time, optical nebular features of Type Ia supernovae (SNe Ia) using a sample consisting of 160 spectra of 27 normal SNe Ia taken from the literature as well as unpublished spectra of SN 2008Q and ASASSN-14lp. Particular attention is given to nebular features between 4000-6000 Ang in terms of temporal changes in width and central wavelength. Analysis of the prominent late-time 4700 Ang feature shows a progressive central wavelength shift from ˜4600 Ang to longer wavelengths out to at least day +300 for our entire sample. We find no evidence for the feature’s red-ward shift slowing or halting at an [Fe III] blend centroid ˜4700 Ang as has been proposed. Two weaker adjacent features at around 4850 and 5000 Ang exhibit similar red shifts to that of the 4700 Ang feature. We conclude that the ubiquitous red shift of these common late-time SN Ia spectral features is not mainly due to a decrease in line velocities of forbidden Fe emissions, but the result of decreasing line velocities and opacity of permitted Fe absorption lines.

  4. Gene Therapy Vector for the Treatment of Glycogen Storage Disease Type Ia (GSD-Ia) | NCI Technology Transfer Center | TTC

    Science.gov (United States)

    GSD-Ia is an inherited disorder of metabolism associated with life-threatening hypoglycemia, hepatic malignancy, and renal failure caused by the deficiency of glucose-6-phosphatase-alpha (G6Pase-alpha or G6PC). NICHD seeks parties to license this invention towards commercialization.

  5. Bone mineral density in glycogen storage disease type Ia and Ib.

    Science.gov (United States)

    Minarich, Laurie A; Kirpich, Alexander; Fiske, Laurie M; Weinstein, David A

    2012-04-05

    Purpose:The aim of this study was to characterize the pathogenesis of low bone mineral density in glycogen storage disease type Ia and Ib.Methods:A retrospective chart review performed at the University of Florida Glycogen Storage Disease Program included patients with glycogen storage disease type Ia and Ib for whom dual-energy X-ray absorptiometry analysis was performed. A Z-score less than -2 SD was considered low. Analysis for association of bone mineral density with age, gender, presence of complications, mean triglyceride and 25-hydroxyvitamin D concentrations, erythrocyte sedimentation rate, duration of granulocyte colony-stimulating factor therapy, and history of corticosteroid use was performed.Results:In glycogen storage disease Ia, 23/42 patients (55%) had low bone mineral density. Low bone mineral density was associated with other disease complications (P = 0.02) and lower mean serum 25-hydroxyvitamin D concentration (P = 0.03). There was a nonsignificant trend toward lower mean triglyceride concentration in the normal bone mineral density group (P = 0.1).In patients with glycogen storage disease type Ib, 8/12 (66.7%) had low bone mineral density. We did not detect an association with duration of granulocyte colony-stimulating factor therapy (P = 0.68), mean triglyceride level (P = 0.267), erythrocyte sedimentation rate (P = 0.3), or 25-hydroxyvitamin D (P = 0.63) concentration, and there was no evidence that corticosteroid therapy was associated with lower bone mineral density (P = 1).Conclusion:In glycogen storage disease type Ia, bone mineral density is associated with other complications and 25-hydroxyvitamin D status. In glycogen storage disease type Ib, bone mineral density was not associated with any covariates analyzed, suggesting multifactorial etiology or reflecting a small sample.Genet Med advance online publication 5 April 2012.

  6. Imaging the atomic structure and local chemistry of platelets in natural type Ia diamond.

    Science.gov (United States)

    Olivier, E J; Neethling, J H; Kroon, R E; Naidoo, S R; Allen, C S; Sawada, H; van Aken, P A; Kirkland, A I

    2018-03-01

    In the past decades, many efforts have been devoted to characterizing {001} platelet defects in type Ia diamond. It is known that N is concentrated at the defect core. However, an accurate description of the atomic structure of the defect and the role that N plays in it is still unknown. Here, by using aberration-corrected transmission electron microscopy and electron energy-loss spectroscopy we have determined the atomic arrangement within platelet defects in a natural type Ia diamond and matched it to a prevalent theoretical model. The platelet has an anisotropic atomic structure with a zigzag ordering of defect pairs along the defect line. The electron energy-loss near-edge fine structure of both carbon K- and nitrogen K-edges obtained from the platelet core is consistent with a trigonal bonding arrangement at interstitial sites. The experimental observations support an interstitial aggregate mode of formation for platelet defects in natural diamond.

  7. TYPE Ia SUPERNOVA LIGHT CURVE INFERENCE: HIERARCHICAL MODELS IN THE OPTICAL AND NEAR-INFRARED

    International Nuclear Information System (INIS)

    Mandel, Kaisey S.; Narayan, Gautham; Kirshner, Robert P.

    2011-01-01

    We have constructed a comprehensive statistical model for Type Ia supernova (SN Ia) light curves spanning optical through near-infrared (NIR) data. A hierarchical framework coherently models multiple random and uncertain effects, including intrinsic supernova (SN) light curve covariances, dust extinction and reddening, and distances. An improved BAYESN Markov Chain Monte Carlo code computes probabilistic inferences for the hierarchical model by sampling the global probability density of parameters describing individual SNe and the population. We have applied this hierarchical model to optical and NIR data of 127 SNe Ia from PAIRITEL, CfA3, Carnegie Supernova Project, and the literature. We find an apparent population correlation between the host galaxy extinction A V and the ratio of total-to-selective dust absorption R V . For SNe with low dust extinction, A V ∼ V ∼ 2.5-2.9, while at high extinctions, A V ∼> 1, low values of R V < 2 are favored. The NIR luminosities are excellent standard candles and are less sensitive to dust extinction. They exhibit low correlation with optical peak luminosities, and thus provide independent information on distances. The combination of NIR and optical data constrains the dust extinction and improves the predictive precision of individual SN Ia distances by about 60%. Using cross-validation, we estimate an rms distance modulus prediction error of 0.11 mag for SNe with optical and NIR data versus 0.15 mag for SNe with optical data alone. Continued study of SNe Ia in the NIR is important for improving their utility as precise and accurate cosmological distance indicators.

  8. Light and Color Curve Properties of Type Ia Supernovae: Theory Versus Observations

    Energy Technology Data Exchange (ETDEWEB)

    Hoeflich, P.; Hsiao, E. Y. [Department of Physics, Florida State University, Tallahassee, FL 32306 (United States); Ashall, C. [Astrophysics Research Institute, Liverpool John Moore University, 146 Brownlow Hill, Liverpool L3 5RF (United Kingdom); Burns, C. R. [Observatories of the Carnegie Institution for Science, 813 Santa Barbara St., Pasadena, CA 91101 (United States); Diamond, T. R. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Phillips, M. M. [Carnegie Observatories, Las Campanas Observatory, Casilla 601 La Serena (Chile); Sand, D. [Physics and Astronomy Department, Texas Tech University, Box 41051, Lubbock, TX 79409-1051 (United States); Stritzinger, M. D. [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000, Aarhus (Denmark); Suntzeff, N.; Krisciunas, K.; Wang, L. [The G.P. and C. Woods Mitchell Institute for Fundamental Physics and Astronomy, Texas A and M University, Department of Physics and Astronomy, 4242 TAMU, College Station, TX 77843 (United States); Contreras, C.; Morrell, N., E-mail: phoeflich77@gmail.com [Departamento de Física, Universidad Técnica Federico Santa Maria, Ava España 1680, Casilla 110-V, Valparaiso (Chile)

    2017-09-01

    We study the optical light curve (LC) relations of Type Ia supernovae (SNe Ia) for their use in cosmology using high-quality photometry published by the Carnegie Supernova Project (CSP-I). We revisit the classical luminosity decline rate (Δ m {sub 15}) relation and the Lira relation, as well as investigate the time evolution of the ( B − V ) color and B ( B − V ), which serves as the basis of the color–stretch relation and Color–MAgnitude Intercept Calibrations (CMAGIC). Our analysis is based on explosion and radiation transport simulations for spherically symmetric delayed-detonation models (DDT) producing normal-bright and subluminous SNe Ia. Empirical LC relations can be understood as having the same physical underpinnings, i.e., opacities, ionization balances in the photosphere, and radioactive energy deposition changing with time from below to above the photosphere. Some three to four weeks past maximum, the photosphere recedes to {sup 56}Ni-rich layers of similar density structure, leading to a similar color evolution. An important secondary parameter is the central density ρ {sub c} of the WD because at higher densities, more electron-capture elements are produced at the expense of {sup 56}Ni production. This results in a Δ m {sub 15} spread of 0.1 mag in normal-bright and 0.7 mag in subluminous SNe Ia and ≈0.2 mag in the Lira relation. We show why color–magnitude diagrams emphasize the transition between physical regimes and enable the construction of templates that depend mostly on Δ m {sub 15} with little dispersion in both the CSP-I sample and our DDT models. This allows intrinsic SN Ia variations to be separated from the interstellar reddening characterized by E ( B − V ) and R {sub B}. Invoking different scenarios causes a wide spread in empirical relations, which may suggest one dominant scenario.

  9. Light and Color Curve Properties of Type Ia Supernovae: Theory Versus Observations

    Science.gov (United States)

    Hoeflich, P.; Hsiao, E. Y.; Ashall, C.; Burns, C. R.; Diamond, T. R.; Phillips, M. M.; Sand, D.; Stritzinger, M. D.; Suntzeff, N.; Contreras, C.; Krisciunas, K.; Morrell, N.; Wang, L.

    2017-09-01

    We study the optical light curve (LC) relations of Type Ia supernovae (SNe Ia) for their use in cosmology using high-quality photometry published by the Carnegie Supernova Project (CSP-I). We revisit the classical luminosity decline rate (Δm 15) relation and the Lira relation, as well as investigate the time evolution of the (B - V) color and B(B - V), which serves as the basis of the color-stretch relation and Color-MAgnitude Intercept Calibrations (CMAGIC). Our analysis is based on explosion and radiation transport simulations for spherically symmetric delayed-detonation models (DDT) producing normal-bright and subluminous SNe Ia. Empirical LC relations can be understood as having the same physical underpinnings, I.e., opacities, ionization balances in the photosphere, and radioactive energy deposition changing with time from below to above the photosphere. Some three to four weeks past maximum, the photosphere recedes to 56Ni-rich layers of similar density structure, leading to a similar color evolution. An important secondary parameter is the central density ρ c of the WD because at higher densities, more electron-capture elements are produced at the expense of 56Ni production. This results in a Δm 15 spread of 0.1 mag in normal-bright and 0.7 mag in subluminous SNe Ia and ≈0.2 mag in the Lira relation. We show why color-magnitude diagrams emphasize the transition between physical regimes and enable the construction of templates that depend mostly on Δm 15 with little dispersion in both the CSP-I sample and our DDT models. This allows intrinsic SN Ia variations to be separated from the interstellar reddening characterized by E(B - V) and R B . Invoking different scenarios causes a wide spread in empirical relations, which may suggest one dominant scenario.

  10. TYPE Ia SUPERNOVA COLORS AND EJECTA VELOCITIES: HIERARCHICAL BAYESIAN REGRESSION WITH NON-GAUSSIAN DISTRIBUTIONS

    International Nuclear Information System (INIS)

    Mandel, Kaisey S.; Kirshner, Robert P.; Foley, Ryan J.

    2014-01-01

    We investigate the statistical dependence of the peak intrinsic colors of Type Ia supernovae (SNe Ia) on their expansion velocities at maximum light, measured from the Si II λ6355 spectral feature. We construct a new hierarchical Bayesian regression model, accounting for the random effects of intrinsic scatter, measurement error, and reddening by host galaxy dust, and implement a Gibbs sampler and deviance information criteria to estimate the correlation. The method is applied to the apparent colors from BVRI light curves and Si II velocity data for 79 nearby SNe Ia. The apparent color distributions of high-velocity (HV) and normal velocity (NV) supernovae exhibit significant discrepancies for B – V and B – R, but not other colors. Hence, they are likely due to intrinsic color differences originating in the B band, rather than dust reddening. The mean intrinsic B – V and B – R color differences between HV and NV groups are 0.06 ± 0.02 and 0.09 ± 0.02 mag, respectively. A linear model finds significant slopes of –0.021 ± 0.006 and –0.030 ± 0.009 mag (10 3 km s –1 ) –1 for intrinsic B – V and B – R colors versus velocity, respectively. Because the ejecta velocity distribution is skewed toward high velocities, these effects imply non-Gaussian intrinsic color distributions with skewness up to +0.3. Accounting for the intrinsic-color-velocity correlation results in corrections to A V extinction estimates as large as –0.12 mag for HV SNe Ia and +0.06 mag for NV events. Velocity measurements from SN Ia spectra have the potential to diminish systematic errors from the confounding of intrinsic colors and dust reddening affecting supernova distances

  11. Exploring the spectroscopic diversity of Type Ia supernovae with DRACULA: a machine learning approach

    Science.gov (United States)

    Sasdelli, M.; Ishida, E. E. O.; Vilalta, R.; Aguena, M.; Busti, V. C.; Camacho, H.; Trindade, A. M. M.; Gieseke, F.; de Souza, R. S.; Fantaye, Y. T.; Mazzali, P. A.

    2016-09-01

    The existence of multiple subclasses of Type Ia supernovae (SNe Ia) has been the subject of great debate in the last decade. One major challenge inevitably met when trying to infer the existence of one or more subclasses is the time consuming, and subjective, process of subclass definition. In this work, we show how machine learning tools facilitate identification of subtypes of SNe Ia through the establishment of a hierarchical group structure in the continuous space of spectral diversity formed by these objects. Using deep learning, we were capable of performing such identification in a four-dimensional feature space (+1 for time evolution), while the standard principal component analysis barely achieves similar results using 15 principal components. This is evidence that the progenitor system and the explosion mechanism can be described by a small number of initial physical parameters. As a proof of concept, we show that our results are in close agreement with a previously suggested classification scheme and that our proposed method can grasp the main spectral features behind the definition of such subtypes. This allows the confirmation of the velocity of lines as a first-order effect in the determination of SN Ia subtypes, followed by 91bg-like events. Given the expected data deluge in the forthcoming years, our proposed approach is essential to allow a quick and statistically coherent identification of SNe Ia subtypes (and outliers). All tools used in this work were made publicly available in the PYTHON package Dimensionality Reduction And Clustering for Unsupervised Learning in Astronomy (DRACULA) and can be found within COINtoolbox (https://github.com/COINtoolbox/DRACULA).

  12. Time-varying sodium absorption in the Type Ia supernova 2013gh

    Science.gov (United States)

    Ferretti, R.; Amanullah, R.; Goobar, A.; Johansson, J.; Vreeswijk, P. M.; Butler, R. P.; Cao, Y.; Cenko, S. B.; Doran, G.; Filippenko, A. V.; Freeland, E.; Hosseinzadeh, G.; Howell, D. A.; Lundqvist, P.; Mattila, S.; Nordin, J.; Nugent, P. E.; Petrushevska, T.; Valenti, S.; Vogt, S.; Wozniak, P.

    2016-07-01

    Context. Temporal variability of narrow absorption lines in high-resolution spectra of Type Ia supernovae (SNe Ia) is studied to search for circumstellar matter. Time series which resolve the profiles of absorption lines such as Na I D or Ca II H&K are expected to reveal variations due to photoionisation and subsequent recombination of the gases. The presence, composition, and geometry of circumstellar matter may hint at the elusive progenitor system of SNe Ia and could also affect the observed reddening law. Aims: To date, there are few known cases of time-varying Na I D absorption in SNe Ia, all of which occurred during relatively late phases of the supernova (SN) evolution. Photoionisation, however, is predicted to occur during the early phases of SNe Ia, when the supernovae peak in the ultraviolet. We attempt, therefore, to observe early-time absorption-line variations by obtaining high-resolution spectra of SNe before maximum light. Methods: We have obtained photometry and high-resolution spectroscopy of SNe Ia 2013gh and iPTF 13dge, to search for absorption-line variations. Furthermore, we study interstellar absorption features in relation to the observed photometric colours of the SNe. Results: Both SNe display deep Na I D and Ca II H&K absorption features. Furthermore, small but significant variations are detected in a feature of the Na I D profile of SN 2013gh. The variations are consistent with either geometric effects of rapidly moving or patchy gas clouds or photoionisation of Na I gas at R ≈ 1019 cm from the explosion. Conclusions: Our analysis indicates that it is necessary to focus on early phases to detect photoionisation effects of gases in the circumstellar medium of SNe Ia. Different absorbers such as Na I and Ca II can be used to probe for matter at different distances from the SNe. The nondetection of variations during early phases makes it possible to put limits on the abundance of the species at those distances. Full Tables 2 and 3 are only

  13. Sensitivity study of explosive nucleosynthesis in Type Ia supernovae: I. Modification of individual thermonuclear reaction rates

    OpenAIRE

    Bravo, Eduardo; Martínez-Pinedo, Gabriel

    2012-01-01

    Background: Type Ia supernovae contribute significantly to the nucleosynthesis of many Fe-group and intermediate-mass elements. However, the robustness of nucleosynthesis obtained via models of this class of explosions has not been studied in depth until now. Purpose: We explore the sensitivity of the nucleosynthesis resulting from thermonuclear explosions of massive white dwarfs with respect to uncertainties in nuclear reaction rates. We put particular emphasis on indentifying ...

  14. A frequent tyrosinase gene mutation in classic, tyrosinase-negative (type IA) oculocutaneous albinism.

    OpenAIRE

    Giebel, L B; Strunk, K M; King, R A; Hanifin, J M; Spritz, R A

    1990-01-01

    We have identified a tyrosinase gene mutation in several patients with classic, tyrosinase-negative (type IA) oculocutaneous albinism. This mutation, which results in a proline----leucine substitution at codon 81 of the tyrosinase polypeptide (EC 1.14.18.1), was observed in 20% (6 of 30) of oculocutaneous albinism alleles from independent probands, but it was not observed in any normal individuals. This mutation thus appears to be a frequent cause of tyrosinase-negative oculocutaneous albinism.

  15. Supernova Type Ia progenitors from merging double white dwarfs: Using a new population synthesis model

    OpenAIRE

    Toonen, Silvia; Nelemans, Gijs; Zwart, Simon Portegies

    2012-01-01

    The study of Type Ia supernovae (SNIa) has lead to greatly improved insights into many fields in astrophysics, however a theoretical explanation of the origin of these events is still lacking. We investigate the potential contribution to the SNIa rate from the population of merging double carbon-oxygen white dwarfs. We aim to develope a model that fits the observed SNIa progenitors as well as the observed close double white dwarf population. We differentiate between two scenarios for the comm...

  16. The Peculiar SN 2005hk: Do Some Type Ia Supernovae Explode As Deflagrations?

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, M.M.; Li, W.; Frieman, J.A.; Blinnikov, S.I.; DePoy, D.; Prieto, J.L.; Milne, P.; Contreras, C.; Folatelli, Gaston; Morrell, N.; Hamuy, M.; Suntzeff, N.B.; Roth, M.; Gonzalez, S.; Krzeminski, W.; Filippenko, A.V.; Freedman, W.L.; Chornock, R.; Jha, S.; Madore, B.F.; Persson, S.E.; /Las Campanas Observ. /UC, Berkeley, Astron. Dept.

    2006-11-14

    We present extensive u{prime}g{prime}r{prime}i{prime} BV RIY JHK{sub s} photometry and optical spectroscopy of SN 2005hk. These data reveal that SN 2005hk was nearly identical in its observed properties to SN 2002cx, which has been called 'the most peculiar known type Ia supernova'. Both supernovae exhibited high ionization SN 1991T-like pre-maximum spectra, yet low peak luminosities like SN 1991bg. The spectra reveal that SN 2005hk, like SN 2002cx, exhibited expansion velocities that were roughly half those of typical type Ia supernovae. The R and I light curves of both supernovae were also peculiar in not displaying the secondary maximum observed for normal type Ia supernovae. Our Y JH photometry of SN 2005hk reveals the same peculiarity in the near-infrared. By combining our optical and near-infrared photometry of SN 2005hk with published ultraviolet light curves obtained with the Swift satellite, we are able to construct a bolometric light curve from {approx} 10 days before to {approx}60 days after B maximum. The shape and unusually low peak luminosity of this light curve, plus the low expansion velocities and absence of a secondary maximum at red and near-infrared wavelengths, are all in reasonable agreement with model calculations of a 3D deflagration which produces {approx} 0.25 M{sub {circle_dot}} of {sup 56}Ni.

  17. Metabolic control of von Gierke disease (glycogen storage disease type Ia) in pregnancy: maintenance of euglycemia with cornstarch.

    Science.gov (United States)

    Johnson, M P; Compton, A; Drugan, A; Evans, M I

    1990-03-01

    In patients with glycogen storage disease type Ia, glucose-6-phosphatase deficiency reduces the liver's ability to generate free glucose from glycogen. Without a continuous, exogenous source of glucose, severe hypoglycemia and subsequent metabolic perturbations occur. Our observations of a patient with glycogen storage disease type Ia, who also had a clomiphene-induced triplet gestation, suggest that cornstarch, which can be catabolized by debranching enzymes, may be used to maintain a constant state of maternal and fetal euglycemia and correct many metabolic abnormalities. Our data suggest that patients with glycogen storage disease type Ia can be safely managed in pregnancy under a tightly monitored and regulated protocol of raw cornstarch feedings.

  18. TYPE Ia SNe ALONG REDSHIFT: THE R(Si II) RATIO AND THE EXPANSION VELOCITIES IN INTERMEDIATE-z SUPERNOVAE

    International Nuclear Information System (INIS)

    Altavilla, G.; Ruiz-Lapuente, P.; Balastegui, A.; Mendez, J.; Espana-Bonet, C.; Irwin, M.; Ellis, R. S.; McMahon, R. M.; Walton, N. A.; Folatelli, G.; Goobar, A.; Nobili, S.; Stanishev, V.; Hillebrandt, W.

    2009-01-01

    We present a study of intermediate-z Type Ia supernovae (SNe Ia) using empirical physical diagrams which permit the investigation of those SNe explosions. This information can be very useful to reduce systematic uncertainties of the Hubble diagram of SNe Ia up to high z. The study of the expansion velocities and the measurement of the ratio R(Si II) allow subtyping of SNe Ia as done in nearby samples. The evolution of this ratio as seen in the diagram R(Si II)-(t) together with R(Si II) max versus (B - V) 0 indicates consistency of the properties at intermediate-z compared with the nearby SNe Ia. At intermediate-z, expansion velocities of Ca II and Si II are found similar to those of the nearby sample. This is found in a sample of six SNe Ia in the range 0.033 ≤z≤ 0.329 discovered within the International Time Programme of SNe Ia for Cosmology and Physics in the spring run of 2002. 7 The program run under Omega and Lambda from Supernovae and the Physics of Supernova Explosions within the International Time Programme at the telescopes of the European Northern Observatory (ENO) at La Palma (Canary Islands, Spain). Two SNe Ia at intermediate-z were of the cool FAINT type, one being an SN1986G-like object highly reddened. The R(Si II) ratio as well as subclassification of the SNe Ia beyond templates help to place SNe Ia in their sequence of brightness and to distinguish between reddened and intrinsically red supernovae. This test can be done with very high z SNe Ia and it will help to reduce systematic uncertainties due to extinction by dust. It should allow to map the high-z sample into the nearby one.

  19. Diabetes mellitus in a patient with glycogen storage disease type Ia: a case report.

    Science.gov (United States)

    Cohn, Aviva; Ohri, Anupam

    2017-11-12

    Glycogen storage disease type Ia is a genetic disorder that is associated with persistent fasting hypoglycemia and the inability to produce endogenous glucose. The development of diabetes with glycogen storage disease is exceedingly rare. The underlying pathogenesis for developing diabetes in these patients is unclear, and there are no guidelines for treatment. We describe a case of a 34-year-old woman of South Asian descent with glycogen storage disease type Ia, who developed uncontrolled diabetes mellitus as a young adult. Hyperglycemia was noted after childbirth, and worsened years later. Treatment for diabetes was difficult due to risks of hypoglycemia from her underlying glycogen storage disease. With minimal hypoglycemic events, the patient's blood glucose improved with exercise in combination with a sodium-glucose co-transporter 2 inhibitor and an alpha glucosidase inhibitor. We report a rare case of diabetes in the setting of glycogen storage disease-Ia. Based on the literature, there appears to be a relationship between glycogen storage disease and metabolic syndrome, which likely plays a role in the pathogenesis. The management of glycemic control remains a clinical challenge, requiring management of both fasting hypoglycemia from glycogen storage disease, as well as post-prandial hyperglycemia from diabetes mellitus.

  20. Type Ia Supernovae Progenitor Problem and the Variation of Fundamental Constants

    Directory of Open Access Journals (Sweden)

    Rybicki M.

    2016-01-01

    Full Text Available Cosmological observations strongly suggest our universe is the interior of an expanding black hole. If the constant mass of the universe is assumed then from the equation for Schwarzschild radius: r S = 2 Gmc it follows that proportionality constant Gc depends linearly on the universe’s radius R u , identified with r S , i.e. Gc Because the Chandrasekhar limit M Ch relates to the speed of light and to the Newton’s constant as M Ch ( c = G 3 = 2 so expansion involves gradual decrease of M Ch . In result, a single white dwarf can alone become the Type Ia supernova progenitor, which provides a complementary solution to single-degenerate and double-degenerate models for SNe Ia. Both alternative scenarios: G R u and c R are analyzed in regard of their consistence with observations, and their consequences to cosmology.

  1. Early Observations of the Type Ia Supernova iPTF 16abc

    Science.gov (United States)

    Miller, Adam; iPTF Collaboration

    2018-01-01

    Early observations of Type Ia supernovae (SNe) provide a unique probe of their progenitor systems and explosion physics. Here, we report the intermediate Palomar Transient Factory (iPTF) discovery of an extraordinarily young SN Ia, iPTF 16abc. By fitting a power law to our early light curve, we infer that first light for the SN only occurred 0.15 +0.15-0.07 d before our first detection. In the ~24 hr after discovery, iPTF 16abc rose by ~2 mag, following a near-linear rise in flux for ~3 d. Strong C II absorption is detected in the early spectra of iPTF 16abc, before disappearing after ~7 d. Unlike the extensively-observed Type Ia SN 2011fe, the (B-V)_0 colors of iPTF 16abc are blue and nearly constant in the days after explosion. We show that our early observations of iPTF 16abc cannot be explained by either SN shock breakout and the associated, subsequent cooling, or the SN ejecta colliding with a stellar companion. Instead, we argue that the early characteristics of iPTF 16abc, including: (i) the rapid, near-linear rise, (ii) the non-evolving blue colors, and (iii) the strong absorption from ionized carbon, are the result of either vigorous mixing of radioactive-Ni in the SN ejecta, or ejecta interaction with diffuse material, or a combination of the two. In the next few years, dozens of very young normal SNe Ia will be discovered, and observations similar to those presented here will constrain the white dwarf explosion mechanism.

  2. Successful Aortic Banding for Type IA Endoleak Due to Neck Dilatation after Endovascular Abdominal Aortic Aneurysm Repair: Case Report.

    Science.gov (United States)

    Tashima, Yasushi; Tamai, Koichi; Shirasugi, Takehiro; Sato, Kenichiro; Yamamoto, Takahiro; Imamura, Yusuke; Yamaguchi, Atsushi; Adachi, Hideo; Kobinata, Toshiyuki

    2017-09-25

    A 69-year-old man with a type IA endoleak that developed approximately 21 months after endovascular abdominal aortic aneurysm repair (EVAR) of a 46 mm diameter aneurysm was referred to our department. He had impaired renal function, Parkinson's disease, and previous cerebral infarction. Computed tomography angiography showed a type IA endoleak with neck dilatation and that the aneurysm had grown to 60 mm in diameter. We decided to perform aortic banding. The type IA endoleak disappeared after banding and the patient was discharged on postoperative day 10. Aortic banding may be effective for type IA endoleak after EVAR and less invasive for high-risk patients in particular.

  3. Early Blue Excess from the Type Ia Supernova 2017cbv and Implications for Its Progenitor

    Energy Technology Data Exchange (ETDEWEB)

    Hosseinzadeh, Griffin; Howell, D. Andrew; McCully, Curtis; Arcavi, Iair [Las Cumbres Observatory, 6740 Cortona Drive, Suite 102, Goleta, CA 93117-5575 (United States); Sand, David J.; Tartaglia, Leonardo [Department of Astronomy/Steward Observatory, 933 North Cherry Avenue, Room N204, Tucson, AZ 85721-0065 (United States); Valenti, Stefano; Bostroem, K. Azalee [Department of Physics, University of California, 1 Shields Avenue, Davis, CA 95616-5270 (United States); Brown, Peter [Mitchell Institute for Fundamental Physics and Astronomy, Texas A and M University, College Station, TX 77843-4242 (United States); Kasen, Daniel [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720-8169 (United States); Hsiao, Eric Y.; Davis, Scott; Shahbandeh, Melissa [Department of Physics, Florida State University, 77 Chieftain Way, Tallahassee, FL 32306-4350 (United States); Stritzinger, Maximilian D., E-mail: griffin@lco.global [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark)

    2017-08-20

    We present very early, high-cadence photometric observations of the nearby Type Ia SN 2017cbv. The light curve is unique in that it has a blue bump during the first five days of observations in the U , B , and g bands, which is clearly resolved given our photometric cadence of 5.7 hr during that time span. We model the light curve as the combination of early shocking of the supernova ejecta against a nondegenerate companion star plus a standard SN Ia component. Our best-fit model suggests the presence of a subgiant star 56 R {sub ☉} from the exploding white dwarf, although this number is highly model-dependent. While this model matches the optical light curve well, it overpredicts the observed flux in the ultraviolet bands. This may indicate that the shock is not a blackbody, perhaps because of line blanketing in the UV. Alternatively, it could point to another physical explanation for the optical blue bump, such as interaction with circumstellar material or an unusual nickel distribution. Early optical spectra of SN 2017cbv show strong carbon (C ii λ 6580) absorption up through day −13 with respect to maximum light, suggesting that the progenitor system contains a significant amount of unburned material. These early results on SN 2017cbv illustrate the power of early discovery and intense follow-up of nearby supernovae to resolve standing questions about the progenitor systems and explosion mechanisms of SNe Ia.

  4. No Evidence of Circumstellar Gas Surrounding Type Ia Supernova SN 2017cbv

    Science.gov (United States)

    Ferretti, Raphael; Amanullah, Rahman; Bulla, Mattia; Goobar, Ariel; Johansson, Joel; Lundqvist, Peter

    2017-12-01

    Nearby type Ia supernovae (SNe Ia), such as SN 2017cbv, are useful events to address the question of what the elusive progenitor systems of the explosions are. Hosseinzadeh et al. suggested that the early blue excess of the light curve of SN 2017cbv could be due to the supernova ejecta interacting with a non-degenerate companion star. Some SN Ia progenitor models suggest the existence of circumstellar (CS) environments in which strong outflows create low-density cavities of different radii. Matter deposited at the edges of the cavities should be at distances at which photoionization due to early ultraviolet (UV) radiation of SNe Ia causes detectable changes to the observable Na I D and Ca II H&K absorption lines. To study possible narrow absorption lines from such material, we obtained a time series of high-resolution spectra of SN 2017cbv at phases between ‑14.8 and +83 days with respect to B-band maximum, covering the time at which photoionization is predicted to occur. Both narrow Na I D and Ca II H&K are detected in all spectra, with no measurable changes between the epochs. We use photoionization models to rule out the presence of Na I and Ca II gas clouds along the line of sight of SN 2017cbv between ∼8 × 1016–2 × 1019 cm and ∼1015–1017 cm, respectively. Assuming typical abundances, the mass of a homogeneous spherical CS gas shell with radius R must be limited to {M}{{H} {{I}}}{CSM}< 3× {10}-4× {(R/{10}17[{cm}])}2 {M}ȯ . The bounds point to progenitor models that deposit little gas in their CS environment.

  5. Relationships between major epitopes of the IA-2 autoantigen in Type 1 diabetes: Implications for determinant spreading.

    Science.gov (United States)

    McLaughlin, Kerry A; Richardson, Carolyn C; Williams, Stefan; Bonifacio, Ezio; Morgan, Diana; Feltbower, Richard G; Powell, Michael; Rees Smith, Bernard; Furmaniak, Jadwiga; Christie, Michael R

    2015-10-01

    Diversification of autoimmunity to islet autoantigens is critical for progression to Type 1 diabetes. B-cells participate in diversification by modifying antigen processing, thereby influencing which peptides are presented to T-cells. In Type 1 diabetes, JM antibodies are associated with T-cell responses to PTP domain peptides. We investigated whether this is the consequence of close structural alignment of JM and PTP domain determinants on IA-2. Fab fragments of IA-2 antibodies with epitopes mapped to the JM domain blocked IA-2 binding of antibodies that recognise epitopes in the IA-2 PTP domain. Peptides from both the JM and PTP domains were protected from degradation during proteolysis of JM antibody:IA-2 complexes and included those representing major T-cell determinants in Type 1 diabetes. The results demonstrate close structural relationships between JM and PTP domain epitopes on IA-2. Stabilisation of PTP domain peptides during proteolysis in JM-specific B-cells may explain determinant spreading in IA-2 autoimmunity. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  6. AMEGO as a supernova alarm: alert, probe and diagnosis of Type Ia explosions

    Science.gov (United States)

    McEnery, Julie E.; Wang, Xilu

    2017-08-01

    A Type Ia supernova (SNIa) could go entirely unnoticed in the Milky Way and nearby starburst galaxies, due to the large optical and near-IR extinction in the dusty environment, low radio and X-ray luminosities, and a weak neutrino signal. But the recent SN2014J confirms that Type Ia supernovae emit γ-ray lines from 56Ni → 56Co → 56Fe radioactive decay, spanning 158 keV to 2.6 MeV. The Galaxy and nearby starbursts are optically thin to γ-rays, so the supernova line flux will suffer negligible extinction. The All-Sky Medium Energy Gamma-ray Observatory (AMEGO) will monitor the entire sky every 3 hours from ~200 keV to >10 GeV. Most of the SNIa gamma-ray lines are squarely within the AMEGO energy range. Thus AMEGO will be an ideal SNIa monitor and early warning system. We will show that the supernova signal is expected to emerge as distinct from the AMEGO background within days after the explosion in the SN2014J shell model. The early stage observations of SNIa will allow us to explore the progenitor types and the nucleosynthesis of SNIa. Moreover, with the excellent line sensitivity, AMEGO will be able to detect the SNIa at a rate of a few events per year and will obtain enough gamma-ray observations over the mission lifetimes (~10 SNIa) to sample the SNIa. The high SNIa detection rate will also enable the precise measurement of the 56Ni mass generated during the Type Ia explosion, which will help us test the cosmic distance calibration and probe the cosmic acceleration.

  7. Type-Ia Supernova Rates to Redshift 2.4 from Clash: The Cluster Lensing and Supernova Survey with Hubble

    Science.gov (United States)

    Graur, O.; Rodney, S. A.; Maoz, D.; Riess, A. G.; Jha, S. W.; Postman, M.; Dahlen, T.; Holoien, T. W.-S.; McCully, C.; Patel, B.; hide

    2014-01-01

    We present the supernova (SN) sample and Type-Ia SN (SN Ia) rates from the Cluster Lensing And Supernova survey with Hubble (CLASH). Using the Advanced Camera for Surveys and the Wide Field Camera 3 on the Hubble Space Telescope (HST), we have imaged 25 galaxy-cluster fields and parallel fields of non-cluster galaxies. We report a sample of 27 SNe discovered in the parallel fields. Of these SNe, approximately 13 are classified as SN Ia candidates, including four SN Ia candidates at redshifts z greater than 1.2.We measure volumetric SN Ia rates to redshift 1.8 and add the first upper limit on the SN Ia rate in the range z greater than 1.8 and less than 2.4. The results are consistent with the rates measured by the HST/ GOODS and Subaru Deep Field SN surveys.We model these results together with previous measurements at z less than 1 from the literature. The best-fitting SN Ia delay-time distribution (DTD; the distribution of times that elapse between a short burst of star formation and subsequent SN Ia explosions) is a power law with an index of 1.00 (+0.06(0.09))/(-0.06(0.10)) (statistical) (+0.12/-0.08) (systematic), where the statistical uncertainty is a result of the 68% and 95% (in parentheses) statistical uncertainties reported for the various SN Ia rates (from this work and from the literature), and the systematic uncertainty reflects the range of possible cosmic star-formation histories. We also test DTD models produced by an assortment of published binary population synthesis (BPS) simulations. The shapes of all BPS double-degenerate DTDs are consistent with the volumetric SN Ia measurements, when the DTD models are scaled up by factors of 3-9. In contrast, all BPS single-degenerate DTDs are ruled out by the measurements at greater than 99% significance level.

  8. Inhibition of Zn(II binding type IA topoisomerases by organomercury compounds and Hg(II.

    Directory of Open Access Journals (Sweden)

    Bokun Cheng

    Full Text Available Type IA topoisomerase activities are essential for resolving DNA topological barriers via an enzyme-mediated transient single strand DNA break. Accumulation of topoisomerase DNA cleavage product can lead to cell death or genomic rearrangement. Many antibacterial and anticancer drugs act as topoisomerase poison inhibitors that form stabilized ternary complexes with the topoisomerase covalent intermediate, so it is desirable to identify such inhibitors for type IA topoisomerases. Here we report that organomercury compounds were identified during a fluorescence based screening of the NIH diversity set of small molecules for topoisomerase inhibitors that can increase the DNA cleavage product of Yersinia pestis topoisomerase I. Inhibition of relaxation activity and accumulation of DNA cleavage product were confirmed for these organomercury compounds in gel based assays of Escherichia coli topoisomerase I. Hg(II, but not As(III, could also target the cysteines that form the multiple Zn(II binding tetra-cysteine motifs found in the C-terminal domains of these bacterial topoisomerase I for relaxation activity inhibition. Mycobacterium tuberculosis topoisomerase I activity is not sensitive to Hg(II or the organomercury compounds due to the absence of the Zn(II binding cysteines. It is significant that the type IA topoisomerases with Zn(II binding domains can still cleave DNA when interfered by Hg(II or organomercury compounds. The Zn(II binding domains found in human Top3α and Top3β may be potential targets of toxic metals and organometallic complexes, with potential consequence on genomic stability and development.

  9. A hybrid type Ia supernova with an early flash triggered by helium-shell detonation

    Science.gov (United States)

    Jiang, Ji-An; Doi, Mamoru; Maeda, Keiichi; Shigeyama, Toshikazu; Nomoto, Ken'Ichi; Yasuda, Naoki; Jha, Saurabh W.; Tanaka, Masaomi; Morokuma, Tomoki; Tominaga, Nozomu; Ivezić, Željko; Ruiz-Lapuente, Pilar; Stritzinger, Maximilian D.; Mazzali, Paolo A.; Ashall, Christopher; Mould, Jeremy; Baade, Dietrich; Suzuki, Nao; Connolly, Andrew J.; Patat, Ferdinando; Wang, Lifan; Yoachim, Peter; Jones, David; Furusawa, Hisanori; Miyazaki, Satoshi

    2017-10-01

    Type Ia supernovae arise from the thermonuclear explosion of white-dwarf stars that have cores of carbon and oxygen. The uniformity of their light curves makes these supernovae powerful cosmological distance indicators, but there have long been debates about exactly how their explosion is triggered and what kind of companion stars are involved. For example, the recent detection of the early ultraviolet pulse of a peculiar, subluminous type Ia supernova has been claimed as evidence for an interaction between a red-giant or a main-sequence companion and ejecta from a white-dwarf explosion. Here we report observations of a prominent but red optical flash that appears about half a day after the explosion of a type Ia supernova. This supernova shows hybrid features of different supernova subclasses, namely a light curve that is typical of normal-brightness supernovae, but with strong titanium absorption, which is commonly seen in the spectra of subluminous ones. We argue that this early flash does not occur through previously suggested mechanisms such as the companion-ejecta interaction. Instead, our simulations show that it could occur through detonation of a thin helium shell either on a near-Chandrasekhar-mass white dwarf, or on a sub-Chandrasekhar-mass white dwarf merging with a less-massive white dwarf. Our finding provides evidence that one branch of previously proposed explosion models—the helium-ignition branch—does exist in nature, and that such a model may account for the explosions of white dwarfs in a mass range wider than previously supposed.

  10. A hybrid type Ia supernova with an early flash triggered by helium-shell detonation.

    Science.gov (United States)

    Jiang, Ji-An; Doi, Mamoru; Maeda, Keiichi; Shigeyama, Toshikazu; Nomoto, Ken'ichi; Yasuda, Naoki; Jha, Saurabh W; Tanaka, Masaomi; Morokuma, Tomoki; Tominaga, Nozomu; Ivezić, Željko; Ruiz-Lapuente, Pilar; Stritzinger, Maximilian D; Mazzali, Paolo A; Ashall, Christopher; Mould, Jeremy; Baade, Dietrich; Suzuki, Nao; Connolly, Andrew J; Patat, Ferdinando; Wang, Lifan; Yoachim, Peter; Jones, David; Furusawa, Hisanori; Miyazaki, Satoshi

    2017-10-04

    Type Ia supernovae arise from the thermonuclear explosion of white-dwarf stars that have cores of carbon and oxygen. The uniformity of their light curves makes these supernovae powerful cosmological distance indicators, but there have long been debates about exactly how their explosion is triggered and what kind of companion stars are involved. For example, the recent detection of the early ultraviolet pulse of a peculiar, subluminous type Ia supernova has been claimed as evidence for an interaction between a red-giant or a main-sequence companion and ejecta from a white-dwarf explosion. Here we report observations of a prominent but red optical flash that appears about half a day after the explosion of a type Ia supernova. This supernova shows hybrid features of different supernova subclasses, namely a light curve that is typical of normal-brightness supernovae, but with strong titanium absorption, which is commonly seen in the spectra of subluminous ones. We argue that this early flash does not occur through previously suggested mechanisms such as the companion-ejecta interaction. Instead, our simulations show that it could occur through detonation of a thin helium shell either on a near-Chandrasekhar-mass white dwarf, or on a sub-Chandrasekhar-mass white dwarf merging with a less-massive white dwarf. Our finding provides evidence that one branch of previously proposed explosion models-the helium-ignition branch-does exist in nature, and that such a model may account for the explosions of white dwarfs in a mass range wider than previously supposed.

  11. Palomar Transient Factory Discovers Another Possible super- Chandrasekhar Type Ia Supernova

    Science.gov (United States)

    Nugent, P. E.; Howell, D. A.; Sullivan, M.; Suzuki, N.; Cucchiara, A.; Botyanszki, J.; Hsiao, E. Y.

    2010-10-01

    The Type Ia supernova science working group of the Palomar Transient Factory (ATEL#1964) reports the discovery of a possible super-Chandrasekhar mass supernova, PTF10xgx. The supernova is at RA = 00:12:23.15, Dec = +02:30:44.1 (J2000) in the galaxy identified as APMUKS(BJ) B000949.39+021401.7 (Maddox et al. 1990, MNRAS, 243, 692). The supernova was discovered and classified by Oarical, an autonomous software framework of the PTF collaboration, based on observations made with the Palomar 48-inch Oschin Schmidt telescope.

  12. Cosmological-model-parameter determination from satellite-acquired type Ia and IIP Supernova Data

    International Nuclear Information System (INIS)

    Podariu, Silviu; Nugent, Peter; Ratra, Bharat

    2000-01-01

    We examine the constraints that satellite-acquired Type Ia and IIP supernova apparent magnitude versus redshift data will place on cosmological model parameters in models with and without a constant or time-variable cosmological constant lambda. High-quality data which could be acquired in the near future will result in tight constraints on these parameters. For example, if all other parameters of a spatially-flat model with a constant lambda are known, the supernova data should constrain the non-relativistic matter density parameter omega to better than 1 (2, 0.5) at 1 sigma with neutral (worst case, best case) assumptions about data quality

  13. On the hydrogen emission from the type Ia supernova 2002ic

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lifan; Baade, Dietrich; Hoflich, Peter; Wheeler, J. Craig; Kawabata, Koji; Nomoto, Ken' ichi

    2003-12-10

    The discovery of SN 2002ic by the Supernova Factory and the subsequent spectroscopic studies have led to the surprising finding that SN 2002ic is a type Ia supernova with strong ejecta-circumstellar interaction. Here we show that nearly 1 year after the explosion the supernova has become fainter overall, but the H-alpha emission has brightened and broadened dramatically compared to earlier observations. We have obtained spectropolarimetry data which show that the hydrogen-rich matter is highly aspherically distributed. These observations suggest that the supernova exploded inside a dense, clumpy, disk-like circumstellar environment.

  14. Cosmic-Ray Lithium Production at the Nova Eruptions Followed by a Type Ia Supernova.

    Science.gov (United States)

    Kawanaka, Norita; Yanagita, Shohei

    2018-01-26

    Recent measurements of cosmic-ray (CR) light nuclei by AMS-02 have shown that there is an unexpected component of CR lithium whose spectral index is harder than that expected from the secondary production scenario. We propose the nearby type Ia supernova following a nova eruption as the origin of lithium nuclei in the CRs. By fitting the data of CR protons, helium, and lithium fluxes provided by AMS-02 with our theoretical model we show that this scenario is consistent with the observations. The observational tests that can check our hypothesis are briefly discussed.

  15. An upper limit on the contribution of accreting white dwarfs to the type Ia supernova rate.

    Science.gov (United States)

    Gilfanov, Marat; Bogdán, Akos

    2010-02-18

    There is wide agreement that type Ia supernovae (used as standard candles for cosmology) are associated with the thermonuclear explosions of white dwarf stars. The nuclear runaway that leads to the explosion could start in a white dwarf gradually accumulating matter from a companion star until it reaches the Chandrasekhar limit, or could be triggered by the merger of two white dwarfs in a compact binary system. The X-ray signatures of these two possible paths are very different. Whereas no strong electromagnetic emission is expected in the merger scenario until shortly before the supernova, the white dwarf accreting material from the normal star becomes a source of copious X-rays for about 10(7) years before the explosion. This offers a means of determining which path dominates. Here we report that the observed X-ray flux from six nearby elliptical galaxies and galaxy bulges is a factor of approximately 30-50 less than predicted in the accretion scenario, based upon an estimate of the supernova rate from their K-band luminosities. We conclude that no more than about five per cent of type Ia supernovae in early-type galaxies can be produced by white dwarfs in accreting binary systems, unless their progenitors are much younger than the bulk of the stellar population in these galaxies, or explosions of sub-Chandrasekhar white dwarfs make a significant contribution to the supernova rate.

  16. Type Ia Supernova Rate Measurements to Redshift 2.5 from Candles: Searching for Prompt Explosions in the Early Universe

    Science.gov (United States)

    Rodney, Steven A.; Riess, Adam G.; Strogler, Louis-Gregory; Dahlen, Tomas; Graur, Or; Casertano, Stefano; Dickinson, Mark E.; Ferguson, Henry C.; Garnavich, Peter; Cenko, Stephen Bradley

    2014-01-01

    The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) was a multi-cycle treasury program on the Hubble Space Telescope(HST) that surveyed a total area of approx. 0.25 deg(sup 2) with approx.900 HST orbits spread across five fields over three years. Within these survey images we discovered 65 supernovae (SNe) of all types, out to z approx. 2.5. We classify approx. 24 of these as Type Ia SNe (SNe Ia) based on host galaxy redshifts and SN photometry (supplemented by grism spectroscopy of six SNe). Here we present a measurement of the volumetric SN Ia rate as a function of redshift, reaching for the first time beyond z = 2 and putting new constraints on SN Ia progenitor models. Our highest redshift bin includes detections of SNe that exploded when the universe was only approx. 3 Gyr old and near the peak of the cosmic star formation history. This gives the CANDELS high redshift sample unique leverage for evaluating the fraction of SNe Ia that explode promptly after formation (500 Myr). Combining the CANDELS rates with all available SN Ia rate measurements in the literature we find that this prompt SN Ia fraction isfP0.530.09stat0.100.10sys0.26, consistent with a delay time distribution that follows a simplet1power law for all timest40 Myr. However, mild tension is apparent between ground-based low-z surveys and space-based high-z surveys. In both CANDELS and the sister HST program CLASH (Cluster Lensing And Supernova Survey with Hubble), we find a low rate of SNe Ia at z > 1. This could be a hint that prompt progenitors are in fact relatively rare, accounting for only 20 of all SN Ia explosions though further analysis and larger samples will be needed to examine that suggestion.

  17. The repair of a type Ia endoleak following thoracic endovascular aortic repair using a stented elephant trunk procedure.

    Science.gov (United States)

    Qi, Rui-Dong; Zhu, Jun-Ming; Liu, Yong-Min; Chen, Lei; Li, Cheng-Nan; Xing, Xiao-Yan; Sun, Li-Zhong

    2018-04-01

    Type Ia endoleaks are not uncommon complications that occur after thoracic endovascular aortic repair (TEVAR). Because aortic arch vessels prevent extension of the landing zone, it is very difficult to manipulate a type Ia endoleak using an extension cuff or stent-graft, especially when the aortic arch is involved. Here, we retrospectively review our experience of surgical treatment of type Ia endoleak after TEVAR using a stented elephant trunk procedure. From July 2010 to August 2016, we treated 17 patients diagnosed with a type Ia endoleak following TEVAR using stented elephant trunk procedure. The mean age of our patients was 52 ± 8 years. The mean interval between TEVAR and the open surgical repair was 38 ± 43 months. All cases of type Ia endoleak (100%) were repaired successfully. There were no in-hospital deaths. One case required reintubation and continuous renal replacement therapy due to renal failure; this patient recovered smoothly before discharge. One other patient suffered a stroke and renal failure and did not fully recover following discharge, or follow-up. During follow-up, there were 3 deaths. Acceptable results were obtained using a stented elephant trunk procedure in patients with a type Ia endoleak after TEVAR. This technique allowed us to repair the proximal aortic arch lesions, surgically correct the type Ia endoleak, and promote false lumen thrombosis in the distal aorta. Implantation of a stented elephant trunk, with or without a concomitant aortic arch procedure, is an alternative approach for this type of lesion. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  18. Proposal for management and dermoscopy follow-up of nevi in patients affected by oculocutaneous albinism type Ia.

    Science.gov (United States)

    Peralta, Rosario; Sabban, Emilia Cohen; Friedman, Paula; Marcucci, Carolina; Bollea Garlatti, Luis A; Galimberti, Gastón; Cabo, Horacio

    2017-01-01

    Albino patients are at great risk for developing cutaneous neoplasms, including melanomas. In this paper we describe the dermatoscopic findings of nevi in two patients with oculocutaneous albinism type Ia (OCA-Ia) highlighting that they manifest a vascular pattern similar to that described for amelanotic melanoma. We propose managing these patients with dermoscopy, using the comparative approach, digital follow up (DFU), and reflectance confocal microscopy as a complementary tool for difficult cases.

  19. Rates and delay times of Type Ia supernovae in the helium-enriched main-sequence donor scenario

    Science.gov (United States)

    Liu, Zheng-Wei; Stancliffe, Richard J.

    2018-01-01

    The nature of the progenitors of Type Ia supernovae (SNe Ia) remains a mystery. Comparing theoretical rates and delay-time distributions of SNe Ia with those inferred observationally can constrain their progenitor models. In this work, taking thermohaline mixing into account in the helium-enriched main-sequence (HEMS) donor scenario, we address rates and delay times of SNe Ia in this channel by combining the results of self-consistent binary evolution calculations with population synthesis models. We find that the Galactic SN Ia rate from the HEMS donor scenario is around 0.6-1.2 × 10-3 yr-1, which is about 30% of the observed rate. Delay times of SNe Ia in this scenario cover a wide range of 0.1-1.0 Gyr. We also present the pre-explosion properties of companion stars in the HEMS donor scenario, which will be helpful for placing constraints on SN Ia progenitors through analyzing their pre-explosion images.

  20. Rates and delay times of Type Ia supernovae in the helium-enriched main-sequence donor scenario

    Science.gov (United States)

    Liu, Zheng-Wei; Stancliffe, Richard J.

    2018-04-01

    The nature of the progenitors of Type Ia supernovae (SNe Ia) remains a mystery. Comparing theoretical rates and delay-time distributions of SNe Ia with those inferred observationally can constrain their progenitor models. In this work, taking thermohaline mixing into account in the helium-enriched main-sequence (HEMS) donor scenario, we address rates and delay times of SNe Ia in this channel by combining the results of self-consistent binary evolution calculations with population synthesis models. We find that the Galactic SN Ia rate from the HEMS donor scenario is around 0.6-1.2 × 10-3 yr-1, which is about 30 per cent of the observed rate. Delay times of SNe Ia in this scenario cover a wide range of 0.1-1.0 Gyr. We also present the pre-explosion properties of companion stars in the HEMS donor scenario, which will be helpful for placing constraints on SN Ia progenitors through analysing their pre-explosion images.

  1. Recovering Type Ia Supernova Spectral Indicators from Low-Resolution Spectroscopy and Photometry

    Science.gov (United States)

    Dixon, Samantha; Nearby Supernova Factory Collaboration, Perlmutter et al. WFIRST Supernova Science Investigation Team

    2018-01-01

    Type Ia supernovae are one of the best tools for measuring cosmological distances, and recent results have used advanced matching techniques to dramatically improve the standardization of supernova brightnesses when spectroscopic data is available. Photometric studies, however, are currently limited in their use for cosmology by as yet unmodeled dispersion in standardized magnitudes. Some fraction of this dispersion is due to diversity among supernovae that is revealed by spectra but not captured by traditional light curve fitters. Several studies in the literature propose using direct measurements of a variety of spectral features to parametrize this diversity and make additional corrections to the magnitudes inferred from light curve fits. A forthcoming paper by Saunders et al., presents a new empirical model of Type Ia supernova spectral time series, based on over 2000 spectrophotometric observations of 241 supernovae from the Nearby Supernova Factory, that captures a wider range of supernova behavior. I will present a study that uses this new empirical model to reconstruct the spectral time series of supernovae observed with a range of signal-to-noise ratios and spectral resolutions in order to explore how well spectral indicators can be recovered from photometry and low-resolution spectroscopy. Using results from the literature, I will also examine how the ability to recover these spectral indicators impacts cosmology, particularly in the context of future surveys (e.g. WFIRST and LSST).

  2. Discovery of the progenitor of the type Ia supernova 2007on.

    Science.gov (United States)

    Voss, Rasmus; Nelemans, Gijs

    2008-02-14

    Type Ia supernovae are exploding stars that are used to measure the accelerated expansion of the Universe and are responsible for most of the iron ever produced. Although there is general agreement that the exploding star is a white dwarf in a binary system, the exact configuration and trigger of the explosion is unclear, which could hamper their use for precision cosmology. Two families of progenitor models have been proposed. In the first, a white dwarf accretes material from a companion until it exceeds the Chandrasekhar mass, collapses and explodes. Alternatively, two white dwarfs merge, again causing catastrophic collapse and an explosion. It has hitherto been impossible to determine if either model is correct. Here we report the discovery of an object in pre-supernova archival X-ray images at the position of the recent type Ia supernova (2007on) in the elliptical galaxy NGC 1404. Deep optical images (also archival) show no sign of this object. From this we conclude that the X-ray source is the progenitor of the supernova, which favours the accretion model for this supernova, although the host galaxy is older (6-9 Gyr) than the age at which the explosions are predicted in the accreting models.

  3. Spectroscopic Determination of the Low Redshift Type Ia Supernova Rate from the Sloan Digital Sky Survey

    Energy Technology Data Exchange (ETDEWEB)

    Krughoff, K.Simon; Connolly, Andrew J.; Frieman, Joshua; SubbaRao, Mark; Kilper, Gary; Schneider, Donald P.

    2011-04-10

    Supernova rates are directly coupled to high mass stellar birth and evolution. As such, they are one of the few direct measures of the history of cosmic stellar evolution. In this paper we describe an probabilistic technique for identifying supernovae within spectroscopic samples of galaxies. We present a study of 52 type Ia supernovae ranging in age from -14 days to +40 days extracted from a parent sample of \\simeq 50,000 spectra from the SDSS DR5. We find a Supernova Rate (SNR) of 0.472^{+0.048}_{-0.039}(Systematic)^{+0.081}_{-0.071}(Statistical)SNu at a redshift of = 0.1. This value is higher than other values at low redshift at the 1{\\sigma}, but is consistent at the 3{\\sigma} level. The 52 supernova candidates used in this study comprise the third largest sample of supernovae used in a type Ia rate determination to date. In this paper we demonstrate the potential for the described approach for detecting supernovae in future spectroscopic surveys.

  4. Cloning and biochemical characterization of Staphylococcus aureus type IA DNA topoisomerase comprised of distinct five domains.

    Science.gov (United States)

    Park, Jung Eun; Kim, Hyun Ik; Park, Jong Woo; Park, Jong Kun; Lee, Jung Sup

    2011-04-01

    DNA topoisomerases play critical roles in regulating DNA topology and are essential enzymes for cell survival. In this study, a gene encoding type IA DNA topoisomerase was cloned from Staphylococcus aureus (S. aureus) sp. strain C-66, and the biochemical properties of recombinant enzyme was characterized. The nucleotide sequence analysis showed that the cloned gene contained an open reading frame (2070 bp) that could encode a polypeptide of 689 amino acids. The cloned gene actually produced 79.1 kDa functional enzyme (named Sau-TopoI) in Escherichia coli (E. coli). Sau-TopoI enzyme purified from E. coli showed ATP-independent and Mg(2+)-dependent manners for relaxing negatively supercoiled DNA. The relaxation activity of Sau-TopoI was inhibited by camptothecin, but not by nalidixic acid and etoposide. Cleavage site mapping showed that the enzyme could preferentially bind to and cleave the sequence GGNN↓CAT (N and ↓ represent any nucleotide and cleavage site, respectively). All these results suggest that the purified enzyme is type IA DNA topoisomerase. In addition, domain mapping analysis showed that the enzyme was composed of conserved four domains (I through IV), together with a variable C-terminal region containing a unique domain V. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Cobalt-56 γ-ray emission lines from the type Ia supernova 2014J.

    Science.gov (United States)

    Churazov, E; Sunyaev, R; Isern, J; Knödlseder, J; Jean, P; Lebrun, F; Chugai, N; Grebenev, S; Bravo, E; Sazonov, S; Renaud, M

    2014-08-28

    A type Ia supernova is thought to be a thermonuclear explosion of either a single carbon-oxygen white dwarf or a pair of merging white dwarfs. The explosion fuses a large amount of radioactive (56)Ni (refs 1-3). After the explosion, the decay chain from (56)Ni to (56)Co to (56)Fe generates γ-ray photons, which are reprocessed in the expanding ejecta and give rise to powerful optical emission. Here we report the detection of (56)Co lines at energies of 847 and 1,238 kiloelectronvolts and a γ-ray continuum in the 200-400 kiloelectronvolt band from the type Ia supernova 2014J in the nearby galaxy M82. The line fluxes suggest that about 0.6 ± 0.1 solar masses of radioactive (56)Ni were synthesized during the explosion. The line broadening gives a characteristic mass-weighted ejecta expansion velocity of 10,000 ± 3,000 kilometres per second. The observed γ-ray properties are in broad agreement with the canonical model of an explosion of a white dwarf just massive enough to be unstable to gravitational collapse, but do not exclude merger scenarios that fuse comparable amounts of (56)Ni.

  6. Downregulation of SIRT1 signaling underlies hepatic autophagy impairment in glycogen storage disease type Ia.

    Directory of Open Access Journals (Sweden)

    Jun-Ho Cho

    2017-05-01

    Full Text Available A deficiency in glucose-6-phosphatase-α (G6Pase-α in glycogen storage disease type Ia (GSD-Ia leads to impaired glucose homeostasis and metabolic manifestations including hepatomegaly caused by increased glycogen and neutral fat accumulation. A recent report showed that G6Pase-α deficiency causes impairment in autophagy, a recycling process important for cellular metabolism. However, the molecular mechanism underlying defective autophagy is unclear. Here we show that in mice, liver-specific knockout of G6Pase-α (L-G6pc-/- leads to downregulation of sirtuin 1 (SIRT1 signaling that activates autophagy via deacetylation of autophagy-related (ATG proteins and forkhead box O (FoxO family of transcriptional factors which transactivate autophagy genes. Consistently, defective autophagy in G6Pase-α-deficient liver is characterized by attenuated expressions of autophagy components, increased acetylation of ATG5 and ATG7, decreased conjugation of ATG5 and ATG12, and reduced autophagic flux. We further show that hepatic G6Pase-α deficiency results in activation of carbohydrate response element-binding protein, a lipogenic transcription factor, increased expression of peroxisome proliferator-activated receptor-γ (PPAR-γ, a lipid regulator, and suppressed expression of PPAR-α, a master regulator of fatty acid β-oxidation, all contributing to hepatic steatosis and downregulation of SIRT1 expression. An adenovirus vector-mediated increase in hepatic SIRT1 expression corrects autophagy defects but does not rectify metabolic abnormalities associated with G6Pase-α deficiency. Importantly, a recombinant adeno-associated virus (rAAV vector-mediated restoration of hepatic G6Pase-α expression corrects metabolic abnormalities, restores SIRT1-FoxO signaling, and normalizes defective autophagy. Taken together, these data show that hepatic G6Pase-α deficiency-mediated down-regulation of SIRT1 signaling underlies defective hepatic autophagy in GSD-Ia.

  7. Can the helium-enriched main-sequence donor scenario hide enough hydrogen to explain Type Ia supernovae?

    Science.gov (United States)

    Liu, Zheng-Wei; Stancliffe, Richard J.

    2017-09-01

    Hydrodynamical simulations predict that a large amount of hydrogen (≳0.1 M⊙) is removed from a hydrogen-rich companion star by the SN explosion in the single-degenerate scenario of Type Ia supernovae (SNe Ia). However, non-detection of hydrogen-rich material in the late-time spectra of SNe Ia suggests that the hydrogen mass stripped from the progenitor system is ≲0.001-0.058 M⊙. In this Letter, we include thermohaline mixing into self-consistent binary evolution calculations for the helium-enriched main-sequence (HEMS) donor channel of SNe Ia for the first time. We find that the swept-up hydrogen masses expected in this channel are around 0.10-0.17 M⊙, which is higher than the observational limits, although the companion star is strongly helium-enriched when the SN explodes. This presents a serious challenge to the HEMS donor channel.

  8. On the Time Variation of Dust Extinction and Gas Absorption for Type Ia Supernovae Observed through a Nonuniform Interstellar Medium

    Science.gov (United States)

    Huang, X.; Aldering, G.; Biederman, M.; Herger, B.

    2017-11-01

    For Type Ia supernovae (SNe Ia) observed through a nonuniform interstellar medium (ISM) in its host galaxy, we investigate whether the nonuniformity can cause observable time variations in dust extinction and in gas absorption due to the expansion of the SN photosphere with time. We show that, owing to the steep spectral index of the ISM density power spectrum, sizable density fluctuation amplitudes at the length scale of typical ISM structures (≳ 10 {pc}) will translate to much smaller fluctuations on the scales of an SN photosphere. Therefore, the typical amplitude of time variation due to a nonuniform ISM, of absorption equivalent widths, and of extinction, would be small. As a result, we conclude that nonuniform ISM density should not impact cosmology measurements based on SNe Ia. We apply our predictions based on the ISM density power-law power spectrum to the observations of two highly reddened SNe Ia, SN 2012cu and SN 2014J.

  9. A spectroscopic look at the gravitationally lensed Type Ia supernova 2016geu at z = 0.409

    Science.gov (United States)

    Cano, Zach; Selsing, Jonatan; Hjorth, Jens; de Ugarte Postigo, Antonio; Christensen, Lise; Gall, Christa; Kann, D. A.

    2018-01-01

    The spectacular success of Type Ia supernovae (SNe Ia) in SN-cosmology is based on the assumption that their photometric and spectroscopic properties are invariant with redshift. However, this fundamental assumption needs to be tested with observations of high-z SNe Ia. To date, the majority of SNe Ia observed at moderate to large redshifts (0.4 ≤ z ≤ 1.0) are faint, and the resultant analyses are based on observations with modest signal-to-noise ratios that impart a degree of ambiguity in their determined properties. In rare cases, however, the Universe offers a helping hand: To date a few SNe Ia have been observed that have had their luminosities magnified by intervening galaxies and galaxy clusters acting as gravitational lenses. In this paper, we present long-slit spectroscopy of the lensed SN Ia 2016geu, which occurred at a redshift of z = 0.409, and was magnified by a factor of ≈55 by a galaxy located at z = 0.216. We compared our spectra, which were obtained a couple of weeks to a couple of months past peak light, with the spectroscopic properties of well-observed, nearby SNe Ia, finding that SN 2016geu's properties are commensurate with those of SNe Ia in the local Universe. Based primarily on the velocity and strength of the Si II λ6355 absorption feature, we find that SN 2016geu can be classified as a high-velocity, high-velocity-gradient and 'core-normal' SN Ia. The strength of various features (measured though their pseudo-equivalent widths) argue against SN 2016geu being a faint, broad-lined, cool or shallow-silicon SN Ia. We conclude that the spectroscopic properties of SN 2016geu imply that it is a normal SN Ia, and when taking previous results by other authors into consideration, there is very little, if any, evolution in the observational properties of SNe Ia up to z ≈ 0.4.

  10. Hepatocytes contribute to residual glucose production in a mouse model for glycogen storage disease type Ia.

    Science.gov (United States)

    Hijmans, Brenda S; Boss, Andreas; van Dijk, Theo H; Soty, Maud; Wolters, Henk; Mutel, Elodie; Groen, Albert K; Derks, Terry G J; Mithieux, Gilles; Heerschap, Arend; Reijngoud, Dirk-Jan; Rajas, Fabienne; Oosterveer, Maaike H

    2017-12-01

    It is a long-standing enigma how glycogen storage disease (GSD) type I patients retain a limited capacity for endogenous glucose production despite the loss of glucose-6-phosphatase activity. Insight into the source of residual endogenous glucose production is of clinical importance given the risk of sudden death in these patients, but so far contradictory mechanisms have been proposed. We investigated glucose-6-phosphatase-independent endogenous glucose production in hepatocytes isolated from a liver-specific GSD Ia mouse model (L-G6pc -/- mice) and performed real-time analysis of hepatic glucose fluxes and glycogen metabolism in L-G6pc -/- mice using state-of-the-art stable isotope methodologies. Here we show that G6pc-deficient hepatocytes are capable of producing glucose. In vivo analysis of hepatic glucose metabolism revealed that the hepatic glucokinase flux was decreased by 95% in L-G6pc -/- mice. It also showed increased glycogen phosphorylase flux in L-G6pc -/- mice, which is coupled to the release of free glucose through glycogen debranching. Although the ex vivo activities of debranching enzyme and lysosomal acid maltase, two major hepatic α-glucosidases, were unaltered in L-G6pc -/- mice, pharmacological inhibition of α-glucosidase activity almost completely abolished residual glucose production by G6pc-deficient hepatocytes. Our data indicate that hepatocytes contribute to residual glucose production in GSD Ia. We show that α-glucosidase activity, i.e. glycogen debranching and/or lysosomal glycogen breakdown, contributes to residual glucose production by GSD Ia hepatocytes. A strong reduction in hepatic GCK flux in L-G6pc-/- mice furthermore limits the phosphorylation of free glucose synthesized by G6pc-deficient hepatocytes, allowing the release of glucose into the circulation. The almost complete abrogation of GCK flux in G6pc-deficient liver also explains the contradictory reports on residual glucose production in GSD Ia patients. (Hepatology

  11. A Swift Look at SN 2011fe: The Earliest Ultraviolet Observations of a Type Ia Supernova

    Science.gov (United States)

    Oates, Samantha; Holland, Stephen; Immler, Stefan; Brown, Peter J.; Dawson, Kyle S.; DePasquale, Massimiliano; Gronwall, Caryl; Kuin, Paul; Mazzali, Paolo; Miline, Peter; hide

    2012-01-01

    We present the earliest ultraviolet (UV) observations of the bright Type Ia supernova SN 2011fe/PTF11kly in the nearby galaxy M101 at a distance of only 6.4 Mpc. It was discovered shortly after explosion by the Palomar Transient Factory and first observed by Swift/UVOT about a day after explosion. The early UV light is well-defined, with approx. 20 data points per filter in the 5 days after explosion. With these early UV observations, we extend the near-UV template of SNe Ia to earlier times for comparison with observations at low and high redshift and report fits from semiempirical models of the explosion. We find the early UV count rates to be well fit by the superposition of two parabolic curves. Finally, we use the early UV flux measurements to examine a possible shock interaction with a non-degenerate companion. We find that even a solar mass companion at a distance of a few solar radii is unlikely at more than 95% confidence.

  12. A rationally designed peptide IA-2-P2 against type 1 diabetes in streptozotocin-induced diabetic mice.

    Science.gov (United States)

    Shen, Lili; Lu, Shiping; Huang, Dongcheng; Li, Guoliang; Liu, Kunfeng; Cao, Rongyue; Zong, Li; Jin, Liang; Wu, Jie

    2017-05-01

    Recent studies have investigated the potential of type 1 diabetes mellitus-related autoantigens, such as heat shock protein 60, to induce immunological tolerance or to suppress the immune response. A functional 24-residue peptide derived from heat shock protein 60 (P277) has shown anti-type 1 diabetes mellitus potential in experimental animals and in clinical studies, but it also carries a potential atherogenic effect. In this study, we have modified P277 to retain an anti-type 1 diabetes mellitus effect and minimize the atherogenic potential by replacing the P277 B epitope with another diabetes-associated autoantigen, insulinoma antigen-2 (IA-2), to create the fusion peptide IA-2-P2. In streptozotocin-induced diabetic C57BL/6J mice, the IA-2-P2 peptide displayed similar anti-diabetic effects to the control P277 peptide. Also, the IA-2-P2 peptide did not show atherogenic activity in a rabbit model. Our findings indicate the potential of IA-2-P2 as a promising vaccine against type 1 diabetes mellitus.

  13. SN 2014J at M82 - I. A middle-class Type Ia supernova by all spectroscopic metrics

    Science.gov (United States)

    Galbany, L.; Moreno-Raya, M. E.; Ruiz-Lapuente, P.; González Hernández, J. I.; Méndez, J.; Vallely, P.; Baron, E.; Domínguez, I.; Hamuy, M.; López-Sánchez, A. R.; Mollá, M.; Catalán, S.; Cooke, E. A.; Fariña, C.; Génova-Santos, R.; Karjalainen, R.; Lietzen, H.; McCormac, J.; Riddick, F. C.; Rubiño-Martín, J. A.; Skillen, I.; Tudor, V.; Vaduvescu, O.

    2016-03-01

    We present the intensive spectroscopic follow up of the Type Ia supernova (SN Ia) 2014J in the starburst galaxy M82. Twenty-seven optical spectra have been acquired from 2014 January 22 to September 1 with the Isaac Newton and William Herschel Telescopes. After correcting the observations for the recession velocity of M82 and for Milky Way and host galaxy extinction, we measured expansion velocities from spectral line blueshifts and pseudo-equivalent width of the strongest features in the spectra, which gives an idea on how elements are distributed within the ejecta. We position SN 2014J in the Benetti, Branch et al. and Wang et al. diagrams. These diagrams are based on properties of the Si II features and provide dynamical and chemical information about the SN ejecta. The nearby SN 2011fe, which showed little evidence for reddening in its host galaxy, is shown as a reference for comparisons. SN 2014J is a border-line object between the Core-normal and Broad-line groups, which corresponds to an intermediate position between low-velocity gradient and high-velocity gradient objects. SN 2014J follows the R(Si II)-Δm15 correlation, which confirms its classification as a relatively normal SN Ia. Our description of the SN Ia in terms of the evolution of the pseudo-equivalent width of various ions as well as the position in the various diagrams put this specific SN Ia into the overall sample of SN Ia.

  14. Clinical and biochemical heterogeneity between patients with glycogen storage disease type IA: the added value of CUSUM for metabolic control.

    Science.gov (United States)

    Peeks, Fabian; Steunenberg, Thomas A H; de Boer, Foekje; Rubio-Gozalbo, M Estela; Williams, Monique; Burghard, Rob; Rajas, Fabienne; Oosterveer, Maaike H; Weinstein, David A; Derks, Terry G J

    2017-09-01

    To study heterogeneity between patients with glycogen storage disease type Ia (GSD Ia), a rare inherited disorder of carbohydrate metabolism caused by the deficiency of glucose-6-phosphatase (G6Pase). Descriptive retrospective study of longitudinal clinical and biochemical data and long-term complications in 20 GSD Ia patients. We included 11 patients with homozygous G6PC mutations and siblings from four families carrying identical G6PC genotypes. To display subtle variations for repeated triglyceride measurements with respect to time for individual patients, CUSUM-analysis graphs were constructed. Patients with different homozygous G6PC mutations showed important differences in height, BMI, and biochemical parameters (i.e., lactate, uric acid, triglyceride, and cholesterol concentrations). Furthermore, CUSUM-analysis predicts and displays subtle changes in longitudinal blood triglyceride concentrations. Siblings in families also displayed important differences in biochemical parameters (i.e., lactate, uric acid, triglycerides, and cholesterol concentrations) and long-term complications (i.e., liver adenomas, nephropathy, and osteopenia/osteoporosis). Differences between GSD Ia patients reflect large clinical and biochemical heterogeneity. Heterogeneity between GSD Ia patients with homozygous G6PC mutations indicate an important role of the G6PC genotype/mutations. Differences between affected siblings suggest an additional role (genetic and/or environmental) of modifying factors defining the GSD Ia phenotype. CUSUM-analysis can facilitate single-patient monitoring of metabolic control and future application of this method may improve precision medicine for patients both with GSD and remaining inherited metabolic diseases.

  15. Very low-density lipoprotein apolipoprotein B-100 turnover in glycogen storage disease type Ia (von Gierke disease).

    Science.gov (United States)

    Wierzbicki, A S; Watt, G F; Lynas, J; Winder, A F; Wray, R

    2001-10-01

    Mixed hyperlipidaemia is a common finding in glycogen storage disease type Ia (GSD Ia). Although cross-sectional studies have demonstrated increases in intermediate-density lipoproteins (IDLs) and reductions in lipoprotein lipase activity, no studies have investigated the dynamics of apolipoprotein B-100 (apo B) metabolism in GSD Ia. This study investigated apoB turnover in GSD Ia using an exogenous labelling method in one sib from a kinship with established GSD Ia. The study demonstrated normal hepatic secretion of very low-density lipoprotein (VLDL), but hypocatabolism of VLDL, probably due to lack of lipoprotein lipase activity. The production rate of IDL was slightly increased, but the turnover rate of low-density lipoprotein was normal. The findings suggest that, as well as a corn starch diet and dietary fat restriction, treatment of severe mixed hyperlipidaemia in GSD Ia and its attendant risk of pancreatitis should possibly involve fibrates that activate lipoprotein lipase and may enhance the clearance of IDL, rather than omega-3 fatty acids, which principally suppress hepatic secretion of VLDL.

  16. Environmental Dependence of Type Ia Supernova Luminosities from a Sample without a Local–Global Difference in Host Star Formation

    Science.gov (United States)

    Kim, Young-Lo; Smith, Mathew; Sullivan, Mark; Lee, Young-Wook

    2018-02-01

    It is established that there is a dependence of the luminosity of type Ia supernovae (SNe Ia) on environment: SNe Ia in young, star-forming, metal-poor stellar populations appear fainter after light-curve shape corrections than those in older, passive, metal-rich environments. This is accounted for in cosmological studies using a global property of the SN host galaxy, typically the host galaxy stellar mass. However, recent low-redshift studies suggest that this effect manifests itself most strongly when using the local star formation rate (SFR) at the SN location, rather than the global SFR or the stellar mass of the host galaxy. At high-redshift, such local SFRs are difficult to determine; here, we show that an equivalent local correction can be made by restricting the SN Ia sample in globally star-forming host galaxies to a low-mass host galaxy subset (≤1010 M ⊙). Comparing this sample of SNe Ia (in locally star-forming environments) to those in locally passive host galaxies, we find that SNe Ia in locally star-forming environments are 0.081 ± 0.018 mag fainter (4.5σ), consistent with the result reported by Rigault et al., but our conclusion is based on a sample ∼5 times larger over a wider redshift range. This is a larger difference than when splitting the SN Ia sample based on global host galaxy SFR or host galaxy stellar mass. This method can be used in ongoing and future high-redshift SN surveys, where local SN Ia environments are difficult to determine.

  17. New mass limit for white dwarfs: super-Chandrasekhar type ia supernova as a new standard candle.

    Science.gov (United States)

    Das, Upasana; Mukhopadhyay, Banibrata

    2013-02-15

    Type Ia supernovae, sparked off by exploding white dwarfs of mass close to the Chandrasekhar limit, play the key role in understanding the expansion rate of the Universe. However, recent observations of several peculiar type Ia supernovae argue for its progenitor mass to be significantly super-Chandrasekhar. We show that strongly magnetized white dwarfs not only can violate the Chandrasekhar mass limit significantly, but exhibit a different mass limit. We establish from a foundational level that the generic mass limit of white dwarfs is 2.58 solar mass. This explains the origin of overluminous peculiar type Ia supernovae. Our finding further argues for a possible second standard candle, which has many far reaching implications, including a possible reconsideration of the expansion history of the Universe.

  18. Sensitivity study of explosive nucleosynthesis in type Ia supernovae: Modification of individual thermonuclear reaction rates

    Science.gov (United States)

    Bravo, Eduardo; Martínez-Pinedo, Gabriel

    2012-05-01

    Background: Type Ia supernovae contribute significantly to the nucleosynthesis of many Fe-group and intermediate-mass elements. However, the robustness of nucleosynthesis obtained via models of this class of explosions has not been studied in depth until now.Purpose: We explore the sensitivity of the nucleosynthesis resulting from thermonuclear explosions of massive white dwarfs with respect to uncertainties in nuclear reaction rates. We put particular emphasis on indentifying the individual reactions rates that most strongly affect the isotopic products of these supernovae.Method: We have adopted a standard one-dimensional delayed detonation model of the explosion of a Chandrasekhar-mass white dwarf and have postprocessed the thermodynamic trajectories of every mass shell with a nucleosynthetic code to obtain the chemical composition of the ejected matter. We have considered increases (decreases) by a factor of 10 on the rates of 1196 nuclear reactions (simultaneously with their inverse reactions), repeating the nucleosynthesis calculations after modification of each reaction rate pair. We have computed as well hydrodynamic models for different rates of the fusion reactions of 12C and of 16O. From the calculations we have selected the reactions that have the largest impact on the supernova yields, and we have computed again the nucleosynthesis using two or three alternative prescriptions for their rates, taken from the JINA REACLIB database. For the three reactions with the largest sensitivity we have analyzed as well the temperature ranges where a modification of their rates has the strongest effect on nucleosynthesis.Results: The nucleosynthesis resulting from the type Ia supernova models is quite robust with respect to variations of nuclear reaction rates, with the exception of the reaction of fusion of two 12C nuclei. The energy of the explosion changes by less than ˜4% when the rates of the reactions 12C+12C or 16O+16O are multiplied by a factor of ×10 or

  19. Glycogen Storage Disease Type Ia in Canines: A Model for Human Metabolic and Genetic Liver Disease

    Science.gov (United States)

    Specht, Andrew; Fiske, Laurie; Erger, Kirsten; Cossette, Travis; Verstegen, John; Campbell-Thompson, Martha; Struck, Maggie B.; Lee, Young Mok; Chou, Janice Y.; Byrne, Barry J.; Correia, Catherine E.; Mah, Cathryn S.; Weinstein, David A.; Conlon, Thomas J.

    2011-01-01

    A canine model of Glycogen storage disease type Ia (GSDIa) is described. Affected dogs are homozygous for a previously described M121I mutation resulting in a deficiency of glucose-6-phosphatase-α. Metabolic, clinicopathologic, pathologic, and clinical manifestations of GSDIa observed in this model are described and compared to those observed in humans. The canine model shows more complete recapitulation of the clinical manifestations seen in humans including “lactic acidosis”, larger size, and longer lifespan compared to other animal models. Use of this model in preclinical trials of gene therapy is described and briefly compared to the murine model. Although the canine model offers a number of advantages for evaluating potential therapies for GSDIa, there are also some significant challenges involved in its use. Despite these challenges, the canine model of GSDIa should continue to provide valuable information about the potential for generating curative therapies for GSDIa as well as other genetic hepatic diseases. PMID:21318173

  20. Glycogen Storage Disease Type Ia in Canines: A Model for Human Metabolic and Genetic Liver Disease

    Directory of Open Access Journals (Sweden)

    Andrew Specht

    2011-01-01

    Full Text Available A canine model of Glycogen storage disease type Ia (GSDIa is described. Affected dogs are homozygous for a previously described M121I mutation resulting in a deficiency of glucose-6-phosphatase-α. Metabolic, clinicopathologic, pathologic, and clinical manifestations of GSDIa observed in this model are described and compared to those observed in humans. The canine model shows more complete recapitulation of the clinical manifestations seen in humans including “lactic acidosis”, larger size, and longer lifespan compared to other animal models. Use of this model in preclinical trials of gene therapy is described and briefly compared to the murine model. Although the canine model offers a number of advantages for evaluating potential therapies for GSDIa, there are also some significant challenges involved in its use. Despite these challenges, the canine model of GSDIa should continue to provide valuable information about the potential for generating curative therapies for GSDIa as well as other genetic hepatic diseases.

  1. iPTF16geu: A multiply imaged, gravitationally lensed type Ia supernova.

    Science.gov (United States)

    Goobar, A; Amanullah, R; Kulkarni, S R; Nugent, P E; Johansson, J; Steidel, C; Law, D; Mörtsell, E; Quimby, R; Blagorodnova, N; Brandeker, A; Cao, Y; Cooray, A; Ferretti, R; Fremling, C; Hangard, L; Kasliwal, M; Kupfer, T; Lunnan, R; Masci, F; Miller, A A; Nayyeri, H; Neill, J D; Ofek, E O; Papadogiannakis, S; Petrushevska, T; Ravi, V; Sollerman, J; Sullivan, M; Taddia, F; Walters, R; Wilson, D; Yan, L; Yaron, O

    2017-04-21

    We report the discovery of a multiply imaged, gravitationally lensed type Ia supernova, iPTF16geu (SN 2016geu), at redshift z = 0.409. This phenomenon was identified because the light from the stellar explosion was magnified more than 50 times by the curvature of space around matter in an intervening galaxy. We used high-spatial-resolution observations to resolve four images of the lensed supernova, approximately 0.3 arc seconds from the center of the foreground galaxy. The observations probe a physical scale of ~1 kiloparsec, smaller than is typical in other studies of extragalactic gravitational lensing. The large magnification and symmetric image configuration imply close alignment between the lines of sight to the supernova and to the lens. The relative magnifications of the four images provide evidence for substructures in the lensing galaxy. Copyright © 2017, American Association for the Advancement of Science.

  2. Dust in a Type Ia Supernova Progenitor: Spitzer Spectroscopy of Kepler's Supernova Remnant

    Science.gov (United States)

    Williams, Brian J.; Borkowski, Kazimierz; Reynolds, Stephen P.; Ghavamian, Parviz; Blair, William P.; Long, Knox S.; Sankrit, Ravi

    2012-01-01

    Characterization of the relatively poorly-understood progenitor systems of Type Ia supernovae is of great importance in astrophysics, particularly given the important cosmological role that these supernovae play. Kepler's Supernova Remnant, the result of a Type Ia supernova, shows evidence for an interaction with a dense circumstellar medium (CSM), suggesting a single-degenerate progenitor system. We present 7.5-38 micron IR spectra of the remnant, obtained with the Spitzer Space Telescope, dominated by emission from warm dust. Broad spectral features at 10 and 18 micron, consistent with various silicate particles, are seen throughout. These silicates were likely formed in the stellar outflow from the progenitor system during the AGB stage of evolution, and imply an oxygen-rich chemistry. In addition to silicate dust, a second component, possibly carbonaceous dust, is necessary to account for the short-wavelength IRS and IRAC data. This could imply a mixed chemistry in the atmosphere of the progenitor system. However, non-spherical metallic iron inclusions within silicate grains provide an alternative solution. Models of collisionally-heated dust emission from fast shocks (> 1000 km/s) propagating into the CSM can reproduce the majority of the emission associated with non-radiative filaments, where dust temperatures are approx 80-100 K, but fail to account for the highest temperatures detected, in excess of 150 K. We find that slower shocks (a few hundred km/s) into moderate density material (n(sub o) approx 50-100 / cubic cm) are the only viable source of heating for this hottest dust. We confirm the finding of an overall density gradient, with densities in the north being an order of magnitude greater than those in the south.

  3. Analysis of recent type Ia supernova data based on evolving dark energy models

    International Nuclear Information System (INIS)

    Park, Jaehong; Park, Chan-Gyung; Hwang, Jai-chan

    2011-01-01

    We study characters of recent type Ia supernova data using evolving dark energy models with changing equation-of-state parameter w. We consider a sudden-jump approximation of w for some chosen redshift spans with double transitions and constrain these models based on the Markov chain Monte Carlo method using the type Ia supernova data (Constitution, Union, Union2), together with the baryon acoustic oscillation A parameter and the cosmic microwave background shift parameter in a flat background. In the double-transition model, the Constitution data shows deviation outside 1σ from the Λ cold dark matter (ΛCDM) model at low (z < or approx. 0.2) and middle (0.2 < or approx. z < or approx. 0.4) redshift bins, whereas no such deviations are noticeable in the Union and Union2 data. By analyzing the Union members in the Constitution set, however, we show that the same difference is actually due to different calibration of the same Union sample in the Constitution set and is not due to new data added in the Constitution set. All detected deviations are within 2σ from the ΛCDM world model. From the ΛCDM mock data analysis, we quantify biases in the dark energy equation-of-state parameters induced by insufficient data with inhomogeneous distribution of data points in the redshift space and distance modulus errors. We demonstrate that the location of the peak in the distribution of arithmetic means (computed from the Markov chain Monte Carlo chain for each mock data) behaves as an unbiased estimator for the average bias, which is valid even for nonsymmetric likelihood distributions.

  4. Delayed detonation models for normal and subluminous type Ia sueprnovae: Absolute brightness, light curves, and molecule formation

    Science.gov (United States)

    Hoflich, P.; Khokhlov, A. M.; Wheeler, J. C.

    1995-01-01

    We compute optical and infrared light curves of the pulsating class of delayed detonation models for Type Ia supernovae (SN Ia's) using an elaborate treatment of the Local Thermodynamic Equilbrium (LTE) radiation transport, equation of state and ionization balance, expansion opacity including the cooling by CO, Co(+), and SiO, and a Monte Carlo gamma-ray deposition scheme. The models have an amount of Ni-56 in the range from approximately or equal to 0.1 solar mass up to 0.7 solar mass depending on the density at which the transition from a deflagration to a detonation occurs. Models with a large nickel production give light curves comparable to those of typical Type Ia supernovae. Subluminous supernovae can be explained by models with a low nickel production. Multiband light curves are presented in comparison with the normally bright event SN 1992bc and the subluminous events Sn 1991bg and SN 1992bo to establish the principle that the delayed detonation paradigm in Chandrasekhar mass models may give a common explosion mechanism accounting for both normal and subluminous SN Ia's. Secondary IR-maxima are formed in the models of normal SN Ia's as a photospheric effect if the photospheric radius continues to increase well after maximum light. Secondary maxima appear later and stronger in models with moderate expansion velocities and with radioactive material closer to the surface. Model light curves for subluminous SN Ia's tend to show only one 'late' IR-maximum. In some delayed detonation models shell-like envelopes form, which consist of unburned carbon and oxygen. The formation of molecules in these envelopes is addressed. If the model retains a C/O-envelope and is subluminous, strong vibration bands of CO may appear, typically several weeks past maximum light. CO should be very weak or absent in normal Sn Ia's.

  5. Mapping of epitopes for autoantibodies to the Type 1 diabetes autoantigen IA-2 by peptide phage display and molecular modelling: Overlap of antibody and T-cell determinants

    DEFF Research Database (Denmark)

    A. Dromey, James; Weenink, Sarah M.; Peters, Günther H.J.

    2004-01-01

    IA-2 is a major target of autoimmunity in type 1 diabetes. IA-2 responsive T cells recognize determinants within regions represented by amino acids 787–817 and 841–869 of the molecule. Epitopes for IA-2 autoantibodies are largely conformational and not well defined. In this study, we used peptide......, and aromatic residues and amino acids contributing to the epitope investigated using site-directed mutagenesis. Mutation of each of amino acids Asn858, Glu836, and Trp799 reduced 96/3 Ab binding by >45%. Mutations of these residues also inhibited binding of serum autoantibodies from IA-2 Ab-positive type 1...... phage display and homology modeling to characterize the epitope of a monoclonal IA-2 Ab (96/3) from a human type 1 diabetic patient. This Ab competes for IA-2 binding with Abs from the majority of patients with type 1 diabetes and therefore binds a region close to common autoantibody epitopes. Alignment...

  6. Evidence for Type Ia Supernova Diversity from Ultraviolet Observations with the Hubble Space Telescope

    Science.gov (United States)

    Wang, Xiaofeng; Wang, Lifan; Filippenko, Alexei; Baron, Eddie; Kromer, Markus; Jack, Dennis; Zhang, Tianmeng; Aldering, Greg; Antilogus, Pierre; Arnett, W. David; hide

    2012-01-01

    We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope, This dataset provides unique spectral time series down to 2000 A. Significant diversity is seen in the near-maximum-light spectra (approx.2000-3500 A) for this small sample. The corresponding photometric data, together with archival data from Swift Ultraviolet/Optical Telescope observations, provide further evidence of increased dispersion in the UV emission with respect to the optical. The peak luminosities measured in the uvw lIF250W filter are found to correlate with the B-band light-curve shape parameter .(Delta)m15(B), but with much larger scatter relative to the correlation in the broad-band B band (e.g., approx. 0.4 mag versus approx. 0.2 mag for those with 0.8 3(sigma), being brighter than normal SNe Ia such as SN 2005cf by approx. 0,9 mag and approx. 2.0 mag in the uvwl1F250W and uvm2/F220W filters, respectively. We show that different progenitor metallicity or line-expansion velocities alone cannot explain such a large discrepancy. Viewing-angle effects, such as due to an asymmetric explosion, may have a significant influence on the flux emitted in the UV region. Detailed modeling is needed to disentangle and quantify the above effects

  7. PTF11kx: A Type Ia Supernova with Hydrogen Emission Persisting after 3.5 Years

    Energy Technology Data Exchange (ETDEWEB)

    Graham, M. L. [Department of Astronomy, University of Washington, Box 351580, U.W., Seattle, WA 98195-1580 (United States); Harris, C. E.; Nugent, P. E.; Kasen, D.; Filippenko, A. V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Fox, O. D. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Silverman, J. M. [Department of Astronomy, University of Texas, Austin, TX 78712 (United States)

    2017-07-10

    The optical transient PTF11kx exhibited both the characteristic spectral features of Type Ia supernovae (SNe Ia) and the signature of ejecta interacting with circumstellar material (CSM) containing hydrogen, indicating the presence of a nondegenerate companion. We present an optical spectrum at 1342 days after peak from Keck Observatory, in which the broad component of H α emission persists with a similar profile as in early-time observations. We also present Spitzer IRAC detections obtained 1237 and 1818 days after peak, and an upper limit from Hubble Space Telescope ultraviolet imaging at 2133 days. We interpret our late-time observations in the context of published results—and reinterpret the early-time observations—in order to constrain the CSM’s physical parameters and to compare to theoretical predictions for recurrent-nova systems. We find that the CSM’s radial extent may be several times the distance between the star and the CSM’s inner edge, and that the CSM column density may be two orders of magnitude lower than previous estimates. We show that the H α luminosity decline is similar to other SNe with CSM interaction and demonstrate how our infrared photometry is evidence for newly formed, collisionally heated dust. We create a model for PTF11kx’s late-time CSM interaction and find that X-ray reprocessing by photoionization and recombination cannot reproduce the observed H α luminosity, suggesting that the X-rays are thermalized and that H α radiates from collisional excitation. Finally, we discuss the implications of our results regarding the progenitor scenario and the geometric properties of the CSM for the PTF11kx system.

  8. A New Approach for Obtaining Cosmological Constraints from Type Ia Supernovae using Approximate Bayesian Computation

    Energy Technology Data Exchange (ETDEWEB)

    Jennings, Elise; Wolf, Rachel; Sako, Masao

    2016-11-09

    Cosmological parameter estimation techniques that robustly account for systematic measurement uncertainties will be crucial for the next generation of cosmological surveys. We present a new analysis method, superABC, for obtaining cosmological constraints from Type Ia supernova (SN Ia) light curves using Approximate Bayesian Computation (ABC) without any likelihood assumptions. The ABC method works by using a forward model simulation of the data where systematic uncertainties can be simulated and marginalized over. A key feature of the method presented here is the use of two distinct metrics, the `Tripp' and `Light Curve' metrics, which allow us to compare the simulated data to the observed data set. The Tripp metric takes as input the parameters of models fit to each light curve with the SALT-II method, whereas the Light Curve metric uses the measured fluxes directly without model fitting. We apply the superABC sampler to a simulated data set of $\\sim$1000 SNe corresponding to the first season of the Dark Energy Survey Supernova Program. Varying $\\Omega_m, w_0, \\alpha$ and $\\beta$ and a magnitude offset parameter, with no systematics we obtain $\\Delta(w_0) = w_0^{\\rm true} - w_0^{\\rm best \\, fit} = -0.036\\pm0.109$ (a $\\sim11$% 1$\\sigma$ uncertainty) using the Tripp metric and $\\Delta(w_0) = -0.055\\pm0.068$ (a $\\sim7$% 1$\\sigma$ uncertainty) using the Light Curve metric. Including 1% calibration uncertainties in four passbands, adding 4 more parameters, we obtain $\\Delta(w_0) = -0.062\\pm0.132$ (a $\\sim14$% 1$\\sigma$ uncertainty) using the Tripp metric. Overall we find a $17$% increase in the uncertainty on $w_0$ with systematics compared to without. We contrast this with a MCMC approach where systematic effects are approximately included. We find that the MCMC method slightly underestimates the impact of calibration uncertainties for this simulated data set.

  9. Identification of genes encoding the type IX secretion system and secreted proteins in Flavobacterium columnare IA-S-4

    Science.gov (United States)

    Flavobacterium columnare, a member of the phylum Bacteroidetes, causes columnaris disease in wild and aquaculture-reared freshwater fish. The mechanisms responsible for columnaris disease are not known. Many members of the phylum Bacteroidetes use type IX secretion systems (T9SSs) to secrete enzymes...

  10. Tycho Brahe's 1572 supernova as a standard type Ia as revealed by its light-echo spectrum.

    Science.gov (United States)

    Krause, Oliver; Tanaka, Masaomi; Usuda, Tomonori; Hattori, Takashi; Goto, Miwa; Birkmann, Stephan; Nomoto, Ken'ichi

    2008-12-04

    Type Ia supernovae are thermonuclear explosions of white dwarf stars in close binary systems. They play an important role as cosmological distance indicators and have led to the discovery of the accelerated expansion of the Universe. Among the most important unsolved questions about supernovae are how the explosion actually proceeds and whether accretion occurs from a companion or by the merging of two white dwarfs. Tycho Brahe's supernova of 1572 (SN 1572) is thought to be one of the best candidates for a type Ia supernova in the Milky Way. The proximity of the SN 1572 remnant has allowed detailed studies, such as the possible identification of the binary companion, and provides a unique opportunity to test theories of the explosion mechanism and the nature of the progenitor. The determination of the hitherto unknown spectroscopic type of this supernova is crucial in relating these results to the diverse population of type Ia supernovae. Here we report an optical spectrum of Tycho's supernova near maximum brightness, obtained from a scattered-light echo more than four centuries after the direct light from the explosion swept past the Earth. We find that SN 1572 belongs to the majority class of normal type Ia supernovae.

  11. Reliable Diagnosis of Carnitine Palmitoyltransferase Type IA Deficiency by Analysis of Plasma Acylcarnitine Profiles

    NARCIS (Netherlands)

    Heiner-Fokkema, M.R.; Vaz, F.M.; Maatman, R.; Kluijtmans, L.A.J.; Spronsen, F.J. van; Reijngoud, D.J.

    2017-01-01

    BACKGROUND: Carnitine palmitoyltransferase IA (CPT-IA) deficiency is an inherited disorder of the carnitine cycle (MIM #255120). Patients affected by this deficiency might be missed easily because of lack of specific and sensitive biochemical markers. In this study, sensitivity and specificity of

  12. Reliable Diagnosis of Carnitine Palmitoyltransferase Type IA Deficiency by Analysis of Plasma Acylcarnitine Profiles

    NARCIS (Netherlands)

    Heiner-Fokkema, M. Rebecca; Vaz, Frédéric M; Maatman, Ronald; Kluijtmans, Leo A J; Spronsen, van FrancJan; Reijngoud, Dirk-Jan; Morava, Eva; Baumgartner, Matthias; Patterson, Marc; Rahman, Shamima; Zschocke, Johannes; Peters, Verena

    2016-01-01

    BACKGROUND: Carnitine palmitoyltransferase IA (CPT-IA) deficiency is an inherited disorder of the carnitine cycle (MIM #255120). Patients affected by this deficiency might be missed easily because of lack of specific and sensitive biochemical markers. In this study, sensitivity and specificity of

  13. Using PS1 and Type Ia Supernovae To Make Most Precise Measurement of Dark Energy To Date

    Science.gov (United States)

    Scolnic, Daniel; Pan-STARRS

    2018-01-01

    I will review recent results that present optical light curves, redshifts, and classifications for 361 spectroscopically confirmed Type Ia supernovae (SNeIa) discovered by the Pan-STARRS1 (PS1) Medium Deep Survey. I will go over improvements to the PS1 SN photometry, astrometry and calibration that reduce the systematic uncertainties in the PS1 SN Ia distances. We combined distances of PS1 SNe with distance estimates of SNIa from SDSS, SNLS, various low-z and HST samples to form the largest combined sample of SN Ia consisting of a total of ~1050 SN Ia ranging from 0.01 cosmological parameters with SNIa. Using the PS1 relative calibration, we have reduced these calibration systematics to the point where they are similar in magnitude to the other major sources of known systematic uncertainties: the nature of the intrinsic scatter of SNIa and modeling of selection effects. I will present measurements of dark energy which are now the most precise measurements of dark energy to date.

  14. Gastric cancer following a liver transplantation for glycogen storage disease type Ia (von Gierke disease): A case report.

    Science.gov (United States)

    Xiao, Hua; Bian, Jianmin; Zhang, Lei; Wang, Zhaoming; Ding, Aixing

    2014-12-01

    Glycogen storage disease type Ia (GSD-Ia; also termed von Gierke disease) is an inherited metabolic disorder resulting from a glucose-6-phosphatase deficiency. Liver transplantation is considered to be the most effective treatment for GSD-Ia patients. In the present study, the case of a patient with GSD-Ia who received a liver transplantation at 17 years of age is presented. During the 12 years following transplantation, the patient's quality of life markedly improved. However, recently, the patient was diagnosed with de novo gastric cancer following a biopsy. Thus, a total gastrectomy with lymph node dissection was performed and the tumor was histologically determined to be a poorly differentiated adenocarcinoma (histopathological stage, pT4N1M0). The patient recovered well and was discharged on postoperative day 10 without any complications. To the best of our knowledge, this is the first case of de novo gastric cancer in a patient with GSD-Ia to be reported.

  15. Nature of type IaB diamonds from the Mir kimberlite pipe (Yakutia): evidence from spectroscopic observation

    Science.gov (United States)

    Yuryeva, Olga P.; Rakhmanova, Mariana I.; Zedgenizov, Dmitry A.

    2017-10-01

    In this study, the specific features of structural defects of type IaB diamonds from the Mir kimberlite pipe (Yakutian diamondiferous province) have been characterized using FTIR and photoluminescence spectroscopy. Mineral inclusions in these diamonds [olivine (Ol), orthopyroxene (OPx), chromite (Chr), sulphide (Sf)] correspond to associations of peridotite rocks at the base of the lithosphere. Nitrogen content in type IaB diamonds shows significant variations, suggesting different growth media and/or several growth stages. A specific feature of these diamonds is the absence or very small amount of platelets, which may be related to annealing during their long-term residence at the temperatures of the base of the lithosphere. All studied diamonds show the presence of hydrogen defects that are active in IR spectra with an intense line at 3107 cm-1, and additional weaker lines at 3085 and 3237 cm-1, which correlated with high nitrogen content. Type IaB diamonds are also characterized by the presence of nitrogen-nickel luminescence centres S2, S3 and 523.2 nm. This feature distinguishes them from superdeep diamonds with extreme nitrogen aggregation states, which clearly attest to different growth conditions and crystallization media of type IaB diamonds from the Mir kimberlite pipe.

  16. The type Ia supernova SNLS-03D3bb from a super-Chandrasekhar-mass white dwarf star.

    Science.gov (United States)

    Howell, D Andrew; Sullivan, Mark; Nugent, Peter E; Ellis, Richard S; Conley, Alexander J; Le Borgne, Damien; Carlberg, Raymond G; Guy, Julien; Balam, David; Basa, Stephane; Fouchez, Dominique; Hook, Isobel M; Hsiao, Eric Y; Neill, James D; Pain, Reynald; Perrett, Kathryn M; Pritchet, Christopher J

    2006-09-21

    The accelerating expansion of the Universe, and the need for dark energy, were inferred from observations of type Ia supernovae. There is a consensus that type Ia supernovae are thermonuclear explosions that destroy carbon-oxygen white dwarf stars that have accreted matter from a companion star, although the nature of this companion remains uncertain. These supernovae are thought to be reliable distance indicators because they have a standard amount of fuel and a uniform trigger: they are predicted to explode when the mass of the white dwarf nears the Chandrasekhar mass of 1.4 solar masses (M(o)). Here we show that the high-redshift supernova SNLS-03D3bb has an exceptionally high luminosity and low kinetic energy that both imply a super-Chandrasekhar-mass progenitor. Super-Chandrasekhar-mass supernovae should occur preferentially in a young stellar population, so this may provide an explanation for the observed trend that overluminous type Ia supernovae occur only in 'young' environments. As this supernova does not obey the relations that allow type Ia supernovae to be calibrated as standard candles, and as no counterparts have been found at low redshift, future cosmology studies will have to consider possible contamination from such events.

  17. Fifteen years of follow-up of a liver transplant recipient with glycogen storage disease type Ia (Von Gierke disease).

    Science.gov (United States)

    Maya Aparicio, A C; Bernal Bellido, C; Tinoco González, J; Garcia Ruíz, S; Aguilar Romero, L; Marín Gómez, L M; Suárez Artacho, G; Alamo Martínez, J M; Serrano Díez-Canedo, J; Padillo Ruíz, F J; Gomez Bravo, M A

    2013-01-01

    Von Gierke's disease or glycogen storage disease type Ia (GSD-Ia) is an infrequent metabolic disease caused by an atypical accumulation of glycogen. The principal cause of this pathology is deficiency of the glucose-6-phosphatase enzyme. Herein we have reported a case of a young man with a history of Von Gierke's disease (GSD-Ia) since childhood who developed hepatocellular adenomatosis brought to light by ultrasounds and TACs. The patient began to develop early chronic renal failure, necessitating simultaneous liver and kidney transplantation. Years later continuous reviews at the nephrology and hepatobiliopancreatic surgery services show he has a good quality of life and a normal hepatorenal profile. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Efficacy of helper-dependent adenovirus vector-mediated gene therapy in murine glycogen storage disease type Ia.

    Science.gov (United States)

    Koeberl, Dwight D; Sun, B; Bird, A; Chen, Y T; Oka, K; Chan, L

    2007-07-01

    Genetic deficiency of glucose-6-phosphatase (G6Pase) underlies glycogen storage disease type Ia (GSD-Ia, also known as von Gierke disease; MIM 232200), an autosomal recessive disorder of metabolism associated with life-threatening hypoglycemia and growth retardation. We tested whether helper-dependent adenovirus (HDAd)-mediated hepatic delivery of G6Pase would lead to prolonged survival and sustained correction of the metabolic abnormalities in G6Pase knockout (KO) mice, a model for a severe form of GSD-Ia. An HDAd vector encoding G6Pase was administered intravenously (2 or 5 x 10(12)vector particles/kg) to 2-week-old (w.o.) G6Pase-KO mice. Following HDAd vector administration survival was prolonged to a median of 7 months, in contrast to untreated affected mice that did not survive past 3 weeks of age. G6Pase levels increased more than tenfold between 3 days and 28 weeks after HDAd injection (P < 0.03). The weights of untreated 2 w.o. G6Pase-KO mice were approximately half those of their unaffected littermates, and treatment stimulated their growth to the size of wild-type mice. Severe hypoglycemia and hypercholesterolemia, which are hallmarks of GSD-Ia both in humans and in mice, were also restored to normalcy by the treatment. Glycogen accumulation in the liver was markedly reduced. The efficacy of HDAd-G6Pase treatment in reversing the physiological and biochemical abnormalities associated with GSD-Ia in affected G6Pase-KO mice justifies further preclinical evaluation in murine and canine models of GSD-Ia.

  19. Highly reddened Type Ia supernova SN 2004ab: another case of anomalous extinction

    Science.gov (United States)

    Chakradhari, N. K.; Sahu, D. K.; Anupama, G. C.; Prabhu, T. P.

    2018-02-01

    We present optical photometric and spectroscopic data for supernova SN 2004ab, a highly reddened normal Type Ia supernova. The total reddening is estimated as E(B - V) = 1.70 ± 0.05 mag. The intrinsic decline-rate parameter Δm15(B)true is 1.27 ± 0.05, and the B-band absolute magnitude at maximum MB^{max} is -19.31 ± 0.25 mag. The host galaxy NGC 5054 is found to exhibit anomalous extinction with a very low value of RV = 1.41 ± 0.06 in the direction of SN 2004ab. The peak bolometric luminosity is derived as log L_bol^max = 43.10 ± 0.07 erg s-1. The photospheric velocity measured from the absorption minimum of the Si II λ6355 line shows a velocity gradient of \\dot{v} = 90 km s-1 d-1, indicating that SN 2004ab is a member of the high velocity gradient (HVG) subgroup. The ratio of the strengths of the Si II λ5972 and λ6355 absorption lines, R(Si II), is estimated as 0.37, while their pseudo-equivalent widths suggest that SN 2004ab belongs to the broad line (BL) type subgroup.

  20. Heteroduplex analysis: a useful screening method for glycogen storage disease type Ia.

    Science.gov (United States)

    Narita, T; Tsuruta, Y; Chiba, K

    1998-04-01

    Glycogen storage disease type Ia (GSDIa), also known as von Gierke disease, is the most common and severe disease of glycogenoses and is caused by a deficiency of glucose-6-phosphatase (G6Pase) and transmitted by an autosomal recessive trait. The encoding gene of G6Pase is composed of only five exons and each exon is short. With heteroduplex analysis (HDA) method, we analyzed the genomic DNA from a patient diagnosed with GSDIa and from her parents. Exons II and IV of the patient showed heteroduplex bands. The mother had a heteroduplex band of exon II, and the father had a heteroduplex band of exon IV. In a mini-slab electrophoresis, exons II and IV of the patient did not show clear heteroduplex bands, but they appeared broader than the others, which made us suspect that they were heteroduplex bands. HDA is an easy and simple method and can verify mutant homozygous DNA fragments by adding wild-type DNA. We think that HDA may be a very useful screening method for the detection of novel genomic mutation in GSDIa in large-scale and mini-slab electrophoresis.

  1. Whimper of a Bang: Documenting the Final Days of the Nearby Type Ia Supernova 2011fe

    Science.gov (United States)

    Shappee, Benjamin

    2017-08-01

    Even though SNe Ia are crucial to cosmological studies as distance indicators, the exact nature of these systems remains theoreltically ambiguous and observationally elusive. However, there is a new hope. The very late-time light curves of SNe Ia harbor important clues to the natures of their progenitor systems. First, the ejecta from the SN will shock heat a non-degenerate companion, leaving it luminous and visible at very late times after the SN has faded . Second, due to nucleosynthetic effects during the explosion, single and double degenerate SNe Ia models are predicted to produce vastly differing amounts of 57Co and 55Fe. 57Co and 55Fe dominate the power of the very late time light curves of SNe Ia after >1050 days after the initial explosion. Broadband observations of the bolometric luminosity at these epochs have the ability to measure the ratio of these two isotopes and thus discriminate between progenitor models. As the brightest SN Ia in nearly 40 years, SN 2011fe offers a prime opportunity to follow a SN Ia to such late epochs. Here we propose HST WFC3 optical and IR photometry of SN 2011fe to observe the transition from a 57Co to a 55Fe powered lightcurve and to constrain a possible shock-heated companion. These observations will place unique constraints on progenitor systems of SNe Ia. SN 2011fe, having been already observed for more than 1600 days and a factor of four million in flux. The observations proposed here would follow SN 2011fe to an epoch 2.5 times later than any other SNe Ia. SN 2011fe is likely to remain the best studied normal SN Ia of our generation and if these observations are not made now, they will likely never be done with Hubble.

  2. Pathogenesis of growth failure and partial reversal with gene therapy in murine and canine Glycogen Storage Disease type Ia.

    Science.gov (United States)

    Brooks, Elizabeth Drake; Little, Dianne; Arumugam, Ramamani; Sun, Baodong; Curtis, Sarah; Demaster, Amanda; Maranzano, Michael; Jackson, Mark W; Kishnani, Priya; Freemark, Michael S; Koeberl, Dwight D

    2013-06-01

    Glycogen Storage Disease type Ia (GSD-Ia) in humans frequently causes delayed bone maturation, decrease in final adult height, and decreased growth velocity. This study evaluates the pathogenesis of growth failure and the effect of gene therapy on growth in GSD-Ia affected dogs and mice. Here we found that homozygous G6pase (-/-) mice with GSD-Ia have normal growth hormone (GH) levels in response to hypoglycemia, decreased insulin-like growth factor (IGF) 1 levels, and attenuated weight gain following administration of GH. Expression of hepatic GH receptor and IGF 1 mRNAs and hepatic STAT5 (phospho Y694) protein levels are reduced prior to and after GH administration, indicating GH resistance. However, restoration of G6Pase expression in the liver by treatment with adeno-associated virus 8 pseudotyped vector expressing G6Pase (AAV2/8-G6Pase) corrected body weight, but failed to normalize plasma IGF 1 in G6pase (-/-) mice. Untreated G6pase (-/-) mice also demonstrated severe delay of growth plate ossification at 12 days of age; those treated with AAV2/8-G6Pase at 14 days of age demonstrated skeletal dysplasia and limb shortening when analyzed radiographically at 6 months of age, in spite of apparent metabolic correction. Moreover, gene therapy with AAV2/9-G6Pase only partially corrected growth in GSD-Ia affected dogs as detected by weight and bone measurements and serum IGF 1 concentrations were persistently low in treated dogs. We also found that heterozygous GSD-Ia carrier dogs had decreased serum IGF 1, adult body weights and bone dimensions compared to wild-type littermates. In sum, these findings suggest that growth failure in GSD-Ia results, at least in part, from hepatic GH resistance. In addition, gene therapy improved growth in addition to promoting long-term survival in dogs and mice with GSD-Ia. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Using late-time optical and near-infrared spectra to constrain Type Ia supernova explosion properties

    Science.gov (United States)

    Maguire, K.; Sim, S. A.; Shingles, L.; Spyromilio, J.; Jerkstrand, A.; Sullivan, M.; Chen, T.-W.; Cartier, R.; Dimitriadis, G.; Frohmaier, C.; Galbany, L.; Gutiérrez, C. P.; Hosseinzadeh, G.; Howell, D. A.; Inserra, C.; Rudy, R.; Sollerman, J.

    2018-03-01

    The late-time spectra of Type Ia supernovae (SNe Ia) are powerful probes of the underlying physics of their explosions. We investigate the late-time optical and near-infrared spectra of seven SNe Ia obtained at the VLT with XShooter at >200 d after explosion. At these epochs, the inner Fe-rich ejecta can be studied. We use a line-fitting analysis to determine the relative line fluxes, velocity shifts, and line widths of prominent features contributing to the spectra ([Fe II], [Ni II], and [Co III]). By focussing on [Fe II] and [Ni II] emission lines in the ˜7000-7500 Å region of the spectrum, we find that the ratio of stable [Ni II] to mainly radioactively-produced [Fe II] for most SNe Ia in the sample is consistent with Chandrasekhar-mass delayed-detonation explosion models, as well as sub-Chandrasekhar mass explosions that have metallicity values above solar. The mean measured Ni/Fe abundance of our sample is consistent with the solar value. The more highly ionised [Co III] emission lines are found to be more centrally located in the ejecta and have broader lines than the [Fe II] and [Ni II] features. Our analysis also strengthens previous results that SNe Ia with higher Si II velocities at maximum light preferentially display blueshifted [Fe II] 7155 Å lines at late times. Our combined results lead us to speculate that the majority of normal SN Ia explosions produce ejecta distributions that deviate significantly from spherical symmetry.

  4. The crossing statistic: dealing with unknown errors in the dispersion of Type Ia supernovae

    International Nuclear Information System (INIS)

    Shafieloo, Arman; Clifton, Timothy; Ferreira, Pedro

    2011-01-01

    We propose a new statistic that has been designed to be used in situations where the intrinsic dispersion of a data set is not well known: The Crossing Statistic. This statistic is in general less sensitive than χ 2 to the intrinsic dispersion of the data, and hence allows us to make progress in distinguishing between different models using goodness of fit to the data even when the errors involved are poorly understood. The proposed statistic makes use of the shape and trends of a model's predictions in a quantifiable manner. It is applicable to a variety of circumstances, although we consider it to be especially well suited to the task of distinguishing between different cosmological models using type Ia supernovae. We show that this statistic can easily distinguish between different models in cases where the χ 2 statistic fails. We also show that the last mode of the Crossing Statistic is identical to χ 2 , so that it can be considered as a generalization of χ 2

  5. EVLA OBSERVATIONS CONSTRAIN THE ENVIRONMENT AND PROGENITOR SYSTEM OF Type Ia SUPERNOVA 2011fe

    International Nuclear Information System (INIS)

    Chomiuk, Laura; Soderberg, Alicia M.; Moe, Maxwell; Margutti, Raffaella; Fong, Wen-fai; Dittmann, Jason A.; Chevalier, Roger A.; Rupen, Michael P.; Badenes, Carles; Fransson, Claes

    2012-01-01

    We report unique Expanded Very Large Array observations of SN 2011fe representing the most sensitive radio study of a Type Ia supernova to date. Our data place direct constraints on the density of the surrounding medium at radii ∼10 15 -10 16 cm, implying an upper limit on the mass loss rate from the progenitor system of M-dot -10 M ☉ yr -1 (assuming a wind speed of 100 km s –1 ) or expansion into a uniform medium with density n CSM ∼ –3 . Drawing from the observed properties of non-conservative mass transfer among accreting white dwarfs, we use these limits on the density of the immediate environs to exclude a phase space of possible progenitor systems for SN 2011fe. We rule out a symbiotic progenitor system and also a system characterized by high accretion rate onto the white dwarf that is expected to give rise to optically thick accretion winds. Assuming that a small fraction, 1%, of the mass accreted is lost from the progenitor system, we also eliminate much of the potential progenitor parameter space for white dwarfs hosting recurrent novae or undergoing stable nuclear burning. Therefore, we rule out much of the parameter space associated with popular single degenerate progenitor models for SN 2011fe, leaving a limited phase space largely inhabited by some double degenerate systems, as well as exotic single degenerates with a sufficient time delay between mass accretion and SN explosion.

  6. TYPE Ia SUPERNOVAE: CAN CORIOLIS FORCE BREAK THE SYMMETRY OF THE GRAVITATIONAL CONFINED DETONATION EXPLOSION MECHANISM?

    Energy Technology Data Exchange (ETDEWEB)

    García-Senz, D. [Departament de Física, UPC, Comte d’Urgell 187, E-08036 Barcelona (Spain); Cabezón, R. M.; Thielemann, F. K. [Departement Physik, Universität Basel. Klingelbergstrasse, 82, 4056 Basel (Switzerland); Domínguez, I., E-mail: domingo.garcia@upc.edu, E-mail: ruben.cabezon@unibas.ch [Departamento de Física, Teórica y del Cosmos, Universidad de Granada, E-18071 Granada (Spain)

    2016-03-10

    Currently the number of models aimed at explaining the phenomena of type Ia supernovae is high and distinguishing between them is a must. In this work we explore the influence of rotation on the evolution of the nuclear flame that drives the explosion in the so-called gravitational confined detonation models. Assuming that the flame starts in a pointlike region slightly above the center of the white dwarf (WD) and adding a moderate amount of angular velocity to the star we follow the evolution of the deflagration using a smoothed particle hydrodynamics code. We find that the results are very dependent on the angle between the rotational axis and the line connecting the initial bubble of burned material with the center of the WD at the moment of ignition. The impact of rotation is larger for angles close to 90° because the Coriolis force on a floating element of fluid is maximum and its principal effect is to break the symmetry of the deflagration. Such symmetry breaking weakens the convergence of the nuclear flame at the antipodes of the initial ignition volume, changing the environmental conditions around the convergence region with respect to non-rotating models. These changes seem to disfavor the emergence of a detonation in the compressed volume at the antipodes and may compromise the viability of the so-called gravitational confined detonation mechanism.

  7. Color dispersion and Milky-Way-like reddening among type Ia supernovae

    International Nuclear Information System (INIS)

    Scolnic, Daniel M.; Riess, Adam G.; Rodney, Steven A.; Brout, Dillon J.; Jones, David O.; Foley, Ryan J.; Rest, Armin

    2014-01-01

    Past analyses of Type Ia supernovae have identified an irreducible scatter of 5%-10% in distance, widely attributed to an intrinsic dispersion in luminosity. Another equally valid source of this scatter is intrinsic dispersion in color. Misidentification of the true source of this scatter can bias both the retrieved color-luminosity relation and cosmological parameter measurements. The size of this bias depends on the magnitude of the intrinsic color dispersion relative to the distribution of colors that correlate with distance. We produce a realistic simulation of a misattribution of intrinsic scatter and find a negative bias in the recovered color-luminosity relation, β, of Δβ ≈ –1.0 (∼33%) and a positive bias in the equation of state parameter, w, of Δw ≈ +0.04 (∼4%). We re-analyze current published datasets with the assumption that the distance scatter is predominantly the result of color. Unlike previous analyses, we find that the data are consistent with a Milky-Way-like reddening law (R V = 3.1) and that a Milky-Way dust model better predicts the asymmetric color-luminosity trends than the conventional luminosity scatter hypothesis. We also determine that accounting for color variation reduces the correlation between various host galaxy properties and Hubble residuals by ∼20%.

  8. Ultraviolet, Optical, and X-Ray Observations of the Type Ia Supernova 2005am with Swift

    Science.gov (United States)

    Brown, P. J.; Holland, S. T.; James, C.; Milne, P.; Roming, P. W. A.; Mason, K. O.; Page, K. L.; Beardmore, A. P.; Burrows, D.; Morgan, A.; Gronwall, C.; Blustin, A. J.; Boyd, P.; Still, M.; Breeveld, A.; de Pasquale, M.; Hunsberger, S.; Ivanushkina, M.; Landsman, W.; McGowan, K.; Poole, T.; Rosen, S.; Schady, P.; Gehrels, N.

    2005-12-01

    We present ultraviolet and optical light curves in six broadband filters and grism spectra obtained by Swift's Ultraviolet/Optical Telescope for the Type Ia supernova SN 2005am. The data were collected beginning about 4 days before the B-band maximum, with excellent coverage of the rapid decline phase and later observations extending out to 69 days after the peak. The optical and near-UV light curve match well those of SN 1992A. The other UV observations constitute the first set of light curves shorter than 2500 Å and allow us to compare the light curve evolution in three UV bands. One interesting feature is that the decay in the intermediate UVM2 band is shallower than in the filters on either side and may result from the bump in the interstellar extinction curve. The UV behavior of this and other low-redshift supernovae can be used to constrain theories of progenitor evolution or to interpret optical light curves of high-redshift supernovae. Using Swift's X-Ray Telescope, we also report the upper limit to SN 2005am's X-ray luminosity to be 6×1039 ergs s-1 in the 0.3-10 keV. This result is derived from 58 ks of exposure time spread out over 7 weeks beginning 4 days before the B-band maximum.

  9. Standardizing Type Ia supernovae optical brightness using near-infrared rebrightening time

    Science.gov (United States)

    Shariff, H.; Dhawan, S.; Jiao, X.; Leibundgut, B.; Trotta, R.; van Dyk, D. A.

    2016-12-01

    Accurate standardization of Type Ia supernovae (SNIa) is instrumental to the usage of SNIa as distance indicators. We analyse a homogeneous sample of 22 low-z SNIa, observed by the Carnegie Supernova Project in the optical and near-infrared (NIR). We study the time of the second peak in the J band, t2, as an alternative standardization parameter of SNIa peak optical brightness, as measured by the standard SALT2 parameter mB. We use BAHAMAS, a Bayesian hierarchical model for SNIa cosmology, to estimate the residual scatter in the Hubble diagram. We find that in the absence of a colour correction, t2 is a better standardization parameter compared to stretch: t2 has a 1σ posterior interval for the Hubble residual scatter of σΔμ = {0.250, 0.257} mag, compared to σΔμ = {0.280, 0.287} mag when stretch (x1) alone is used. We demonstrate that when employed together with a colour correction, t2 and stretch lead to similar residual scatter. Using colour, stretch and t2 jointly as standardization parameters does not result in any further reduction in scatter, suggesting that t2 carries redundant information with respect to stretch and colour. With a much larger SNIa NIR sample at higher redshift in the future, t2 could be a useful quantity to perform robustness checks of the standardization procedure.

  10. Acoustically accessible window determination for ultrasound mediated treatment of glycogen storage disease type Ia patients

    Science.gov (United States)

    Wang, Shutao; Raju, Balasundar I.; Leyvi, Evgeniy; Weinstein, David A.; Seip, Ralf

    2012-10-01

    Glycogen storage disease type Ia (GSDIa) is caused by an inherited single-gene defect resulting in an impaired glycogen to glucose conversion pathway. Targeted ultrasound mediated delivery (USMD) of plasmid DNA (pDNA) to liver in conjunction with microbubbles may provide a potential treatment for GSDIa patients. As the success of USMD treatments is largely dependent on the accessibility of the targeted tissue by the focused ultrasound beam, this study presents a quantitative approach to determine the acoustically accessible liver volume in GSDIa patients. Models of focused ultrasound beam profiles for transducers of varying aperture and focal lengths were applied to abdomen models reconstructed from suitable CT and MRI images. Transducer manipulations (simulating USMD treatment procedures) were implemented via transducer translations and rotations with the intent of targeting and exposing the entire liver to ultrasound. Results indicate that acoustically accessible liver volumes can be as large as 50% of the entire liver volume for GSDIa patients and on average 3 times larger compared to a healthy adult group due to GSDIa patients' increased liver size. Detailed descriptions of the evaluation algorithm, transducer-and abdomen models are presented, together with implications for USMD treatments of GSDIa patients and transducer designs for USMD applications.

  11. EXPLORING THE POTENTIAL DIVERSITY OF EARLY TYPE IA SUPERNOVA LIGHT CURVES

    Energy Technology Data Exchange (ETDEWEB)

    Piro, Anthony L. [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Morozova, Viktoriya S., E-mail: piro@obs.carnegiescience.edu [Theoretical Astrophysics, California Institute of Technology, 1200 E California Boulevard, M/C 350-17, Pasadena, CA 91125 (United States)

    2016-07-20

    During the first several days after explosion, Type Ia supernova light curves probe the outer layers of the exploding star, and therefore provide important clues for identifying their progenitors. We investigate how both the shallow {sup 56}Ni distribution and the presence of circumstellar material shape these early light curves. This is performed using a series of numerical experiments with parameterized properties for systematic exploration. Although not all of the considered models may be realized in nature (and indeed there are arguments why some of them should not occur), the spirit of this work is to provide a broader exploration of the diversity of possibilities. We find that shallower {sup 56}Ni leads to steeper, bluer light curves. Differences in the shape of the rise can introduce errors in estimating the explosion time, and thus impact efforts to infer upper limits on the progenitor or companion radius from a lack of observed shock cooling emission. Circumstellar material can lead to significant luminosity during the first few days, but its presence can be difficult to identify depending on the degree of nickel mixing. In some cases, the hot emission of circumstellar material may even lead to a signature similar to an interaction with a companion, and thus in the future additional diagnostics should be gathered for properly assessing early light curves.

  12. Hepatic mitochondrial dysfunction is a feature of Glycogen Storage Disease Type Ia (GSDIa).

    Science.gov (United States)

    Farah, Benjamin L; Sinha, Rohit A; Wu, Yajun; Singh, Brijesh K; Lim, Andrea; Hirayama, Masahiro; Landau, Dustin J; Bay, Boon Huat; Koeberl, Dwight D; Yen, Paul M

    2017-03-20

    Glycogen storage disease type Ia (GSDIa, von Gierke disease) is the most common glycogen storage disorder. It is caused by the deficiency of glucose-6-phosphatase, an enzyme which catalyses the final step of gluconeogenesis and glycogenolysis. Clinically, GSDIa is characterized by fasting hypoglycaemia and hepatic glycogen and triglyceride overaccumulation. The latter leads to steatohepatitis, cirrhosis, and the formation of hepatic adenomas and carcinomas. Currently, little is known about the function of various organelles and their impact on metabolism in GSDIa. Accordingly, we investigated mitochondrial function in cell culture and mouse models of GSDIa. We found impairments in oxidative phosphorylation and changes in TCA cycle metabolites, as well as decreased mitochondrial membrane potential and deranged mitochondrial ultra-structure in these model systems. Mitochondrial content also was decreased, likely secondary to decreased mitochondrial biogenesis. These deleterious effects culminated in the activation of the mitochondrial apoptosis pathway. Taken together, our results demonstrate a role for mitochondrial dysfunction in the pathogenesis of GSDIa, and identify a new potential target for the treatment of this disease. They also provide new insight into the role of carbohydrate overload on mitochondrial function in other hepatic diseases, such as non-alcoholic fatty liver disease.

  13. Neonatal Gene Therapy of Glycogen Storage Disease Type Ia Using a Feline Immunodeficiency Virus–based Vector

    Science.gov (United States)

    Grinshpun, Albert; Condiotti, Reba; N Waddington, Simon; Peer, Michael; Zeig, Eli; Peretz, Sima; Simerzin, Alina; Chou, Janice; Pann, Chi-Jiunn; Giladi, Hilla; Galun, Eithan

    2010-01-01

    Glycogen storage disease type Ia (GSD-Ia), also known as von Gierke disease, is caused by a deficiency of glucose-6-phosphatase-α (G6Pase), a key enzyme in glucose homeostasis. From birth, affected individuals cannot maintain normal blood glucose levels and suffer from a variety of metabolic disorders, leading to life-threatening complications. Gene therapy has been proposed as a possible option for treatment of this illness. Vectors have been constructed from feline immunodeficiency virus (FIV), a nonprimate lentivirus, because the wild-type virus does not cause disease in humans. Previously, we have shown that these vectors are capable of integrating stably into hepatocyte cell lines and adult murine livers and lead to long-term transgene expression. In the current work, we have assessed the ability to attenuate disease symptoms in a murine model of GSD-Ia. Single administration of FIV vectors containing the human G6Pase gene to G6Pase-α−/− mice did not change the biochemical and pathological phenotype. However, a double neonatal administration protocol led to normalized blood glucose levels, significantly extended survival, improved body weight, and decreased accumulation of liver glycogen associated with the disease. This approach shows a promising paradigm for treating GSD-Ia patients early in life thereby avoiding long-term consequences. PMID:20571544

  14. Neonatal gene therapy of glycogen storage disease type Ia using a feline immunodeficiency virus-based vector.

    Science.gov (United States)

    Grinshpun, Albert; Condiotti, Reba; Waddington, Simon N; Peer, Michael; Zeig, Eli; Peretz, Sima; Simerzin, Alina; Chou, Janice; Pann, Chi-Jiunn; Giladi, Hilla; Galun, Eithan

    2010-09-01

    Glycogen storage disease type Ia (GSD-Ia), also known as von Gierke disease, is caused by a deficiency of glucose-6-phosphatase-alpha (G6Pase), a key enzyme in glucose homeostasis. From birth, affected individuals cannot maintain normal blood glucose levels and suffer from a variety of metabolic disorders, leading to life-threatening complications. Gene therapy has been proposed as a possible option for treatment of this illness. Vectors have been constructed from feline immunodeficiency virus (FIV), a nonprimate lentivirus, because the wild-type virus does not cause disease in humans. Previously, we have shown that these vectors are capable of integrating stably into hepatocyte cell lines and adult murine livers and lead to long-term transgene expression. In the current work, we have assessed the ability to attenuate disease symptoms in a murine model of GSD-Ia. Single administration of FIV vectors containing the human G6Pase gene to G6Pase-alpha(-/-) mice did not change the biochemical and pathological phenotype. However, a double neonatal administration protocol led to normalized blood glucose levels, significantly extended survival, improved body weight, and decreased accumulation of liver glycogen associated with the disease. This approach shows a promising paradigm for treating GSD-Ia patients early in life thereby avoiding long-term consequences.

  15. DNA targeting by the type I-G and type I-A CRISPR–Cas systems of Pyrococcus furiosus

    Science.gov (United States)

    Elmore, Joshua; Deighan, Trace; Westpheling, Jan; Terns, Rebecca M.; Terns, Michael P.

    2015-01-01

    CRISPR–Cas systems silence plasmids and viruses in prokaryotes. CRISPR–Cas effector complexes contain CRISPR RNAs (crRNAs) that include sequences captured from invaders and direct CRISPR-associated (Cas) proteins to destroy corresponding invader nucleic acids. Pyrococcus furiosus (Pfu) harbors three CRISPR–Cas immune systems: a Cst (Type I-G) system with an associated Cmr (Type III-B) module at one locus, and a partial Csa (Type I-A) module (lacking known invader sequence acquisition and crRNA processing genes) at another locus. The Pfu Cmr complex cleaves complementary target RNAs, and Csa systems have been shown to target DNA, while the mechanism by which Cst complexes silence invaders is unknown. In this study, we investigated the function of the Cst as well as Csa system in Pfu strains harboring a single CRISPR–Cas system. Plasmid transformation assays revealed that the Cst and Csa systems both function by DNA silencing and utilize similar flanking sequence information (PAMs) to identify invader DNA. Silencing by each system specifically requires its associated Cas3 nuclease. crRNAs from the 7 shared CRISPR loci in Pfu are processed for use by all 3 effector complexes, and Northern analysis revealed that individual effector complexes dictate the profile of mature crRNA species that is generated. PMID:26519471

  16. In Vivo Zinc Finger Nuclease-mediated Targeted Integration of a Glucose-6-phosphatase Transgene Promotes Survival in Mice With Glycogen Storage Disease Type IA

    Science.gov (United States)

    Landau, Dustin J; Brooks, Elizabeth Drake; Perez-Pinera, Pablo; Amarasekara, Hiruni; Mefferd, Adam; Li, Songtao; Bird, Andrew; Gersbach, Charles A; Koeberl, Dwight D

    2016-01-01

    Glycogen storage disease type Ia (GSD Ia) is caused by glucose-6-phosphatase (G6Pase) deficiency in association with severe, life-threatening hypoglycemia that necessitates lifelong dietary therapy. Here we show that use of a zinc-finger nuclease (ZFN) targeted to the ROSA26 safe harbor locus and a ROSA26-targeting vector containing a G6PC donor transgene, both delivered with adeno-associated virus (AAV) vectors, markedly improved survival of G6Pase knockout (G6Pase-KO) mice compared with mice receiving the donor vector alone (P Ia, as compared with normal littermates, at 8 months following vector administration (P Ia. PMID:26865405

  17. AGAINST THE WIND: RADIO LIGHT CURVES OF TYPE IA SUPERNOVAE INTERACTING WITH LOW-DENSITY CIRCUMSTELLAR SHELLS

    International Nuclear Information System (INIS)

    Harris, Chelsea E.; Nugent, Peter E.; Kasen, Daniel N.

    2016-01-01

    For decades a wide variety of observations spanning the radio through optical and on to the X-ray have attempted to uncover signs of type Ia supernovae (SNe Ia) interacting with a circumstellar medium (CSM). The goal of these studies is to constrain the nature of the hypothesized SN Ia mass-donor companion. A continuous CSM is typically assumed when interpreting observations of interaction. However, while such models have been successfully applied to core-collapse SNe, the assumption of continuity may not be accurate for SNe Ia, because shells of CSM could be formed by pre-supernova eruptions (novae). In this work, we model the interaction of SNe with a spherical, low-density, finite-extent CSM and create a suite of synthetic radio synchrotron light curves. We find that CSM shells produce sharply peaked light curves. We also identify a fiducial set of models that obey a common evolution and can be used to generate radio light curves for an interaction with an arbitrary shell. The relations obeyed by the fiducial models can be used to deduce CSM properties from radio observations; we demonstrate this by applying them to the nondetections of SN 2011fe and SN 2014J. Finally, we explore a multiple shell CSM configuration and describe its more complicated dynamics and the resultant radio light curves.

  18. AGAINST THE WIND: RADIO LIGHT CURVES OF TYPE IA SUPERNOVAE INTERACTING WITH LOW-DENSITY CIRCUMSTELLAR SHELLS

    Energy Technology Data Exchange (ETDEWEB)

    Harris, Chelsea E.; Nugent, Peter E.; Kasen, Daniel N., E-mail: chelseaharris@berkeley.edu [Astronomy Department, University of California Berkeley, Berkeley, CA (United States)

    2016-06-01

    For decades a wide variety of observations spanning the radio through optical and on to the X-ray have attempted to uncover signs of type Ia supernovae (SNe Ia) interacting with a circumstellar medium (CSM). The goal of these studies is to constrain the nature of the hypothesized SN Ia mass-donor companion. A continuous CSM is typically assumed when interpreting observations of interaction. However, while such models have been successfully applied to core-collapse SNe, the assumption of continuity may not be accurate for SNe Ia, because shells of CSM could be formed by pre-supernova eruptions (novae). In this work, we model the interaction of SNe with a spherical, low-density, finite-extent CSM and create a suite of synthetic radio synchrotron light curves. We find that CSM shells produce sharply peaked light curves. We also identify a fiducial set of models that obey a common evolution and can be used to generate radio light curves for an interaction with an arbitrary shell. The relations obeyed by the fiducial models can be used to deduce CSM properties from radio observations; we demonstrate this by applying them to the nondetections of SN 2011fe and SN 2014J. Finally, we explore a multiple shell CSM configuration and describe its more complicated dynamics and the resultant radio light curves.

  19. An Empirical Fitting Method for Type Ia Supernova Light Curves: A Case Study of SN 2011fe

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, WeiKang; Filippenko, Alexei V., E-mail: zwk@astro.berkeley.edu [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States)

    2017-03-20

    We present a new empirical fitting method for the optical light curves of Type Ia supernovae (SNe Ia). We find that a variant broken-power-law function provides a good fit, with the simple assumption that the optical emission is approximately the blackbody emission of the expanding fireball. This function is mathematically analytic and is derived directly from the photospheric velocity evolution. When deriving the function, we assume that both the blackbody temperature and photospheric velocity are constant, but the final function is able to accommodate these changes during the fitting procedure. Applying it to the case study of SN 2011fe gives a surprisingly good fit that can describe the light curves from the first-light time to a few weeks after peak brightness, as well as over a large range of fluxes (∼5 mag, and even ∼7 mag in the g band). Since SNe Ia share similar light-curve shapes, this fitting method has the potential to fit most other SNe Ia and characterize their properties in large statistical samples such as those already gathered and in the near future as new facilities become available.

  20. Utilizing the Updated Gamma-Ray Bursts and Type Ia Supernovae to Constrain the Cardassian Expansion Model and Dark Energy

    Directory of Open Access Journals (Sweden)

    Jun-Jie Wei

    2015-01-01

    Full Text Available We update gamma-ray burst (GRB luminosity relations among certain spectral and light-curve features with 139 GRBs. The distance modulus of 82 GRBs at z>1.4 can be calibrated with the sample at z≤1.4 by using the cubic spline interpolation method from the Union2.1 Type Ia supernovae (SNe Ia set. We investigate the joint constraints on the Cardassian expansion model and dark energy with 580 Union2.1 SNe Ia sample (z<1.4 and 82 calibrated GRBs’ data (1.4Ia significantly improves the constraint on Ωm-ΩΛ plane. In the Cardassian expansion model, the best fit is Ωm=0.24-0.15+0.15 and n=0.16-0.52+0.30  (1σ, which is consistent with the ΛCDM cosmology (n=0 in the 1σ confidence region. We also discuss two dark energy models in which the equation of state w(z is parameterized as w(z=w0 and w(z=w0+w1z/(1+z, respectively. Based on our analysis, we see that our universe at higher redshift up to z=8.2 is consistent with the concordance model within 1σ confidence level.

  1. Evidence for Sub-Chandrasekhar Mass Type Ia Supernovae from an Extensive Survey of Radiative Transfer Models

    Science.gov (United States)

    Goldstein, Daniel A.; Kasen, Daniel

    2018-01-01

    There are two classes of viable progenitors for normal Type Ia supernovae (SNe Ia): systems in which a white dwarf explodes at the Chandrasekhar mass ({M}{ch}), and systems in which a white dwarf explodes below the Chandrasekhar mass (sub-{M}{ch}). It is not clear which of these channels is dominant; observations and light-curve modeling have provided evidence for both. Here we use an extensive grid of 4500 time-dependent, multiwavelength radiation transport simulations to show that the sub-{M}{ch} model can reproduce the entirety of the width–luminosity relation, while the {M}{ch} model can only produce the brighter events (0.8models that vary the mass, kinetic energy, and compositional structure of the ejecta, thereby realizing a broad range of possible outcomes of white dwarf explosions. We provide fitting functions based on our large grid of detailed simulations that map observable properties of SNe Ia, such as peak brightness and light-curve width, to physical parameters such as {}56{Ni} and total ejected mass. These can be used to estimate the physical properties of observed SNe Ia.

  2. Growth hormone-releasing hormone resistance in pseudohypoparathyroidism type ia: new evidence for imprinting of the Gs alpha gene.

    Science.gov (United States)

    Mantovani, Giovanna; Maghnie, Mohamad; Weber, Giovanna; De Menis, Ernesto; Brunelli, Valeria; Cappa, Marco; Loli, Paola; Beck-Peccoz, Paolo; Spada, Anna

    2003-09-01

    Heterozygous inactivating mutations in the Gs alpha gene cause Albright's hereditary osteodystrophy. Consistent with the observation that only maternally inherited mutations lead to resistance to hormone action [pseudohypoparathyroidism type Ia (PHP Ia)], recent studies provided evidence for a predominant maternal origin of Gs alpha transcripts in endocrine organs, such as thyroid, gonad, and pituitary. The aim of this study was to investigate the presence of pituitary resistance to hypothalamic hormones acting via Gs alpha-coupled receptors in patients with PHP Ia. Six of nine patients showed an impaired GH responsiveness to GHRH plus arginine, consistent with a complete GH deficiency (GH peak from 2.6-8.6 microg/liter, normal > 16.5), and partial (GH peak 13.9 and 13.6 microg/liter) and normal responses were found in two and one patient, respectively. Accordingly, IGF-I levels were below and in the low-normal range in seven and two patients. All patients had a normal cortisol response to 1 microg ACTH test, suggesting a normal corticotroph function that was confirmed by a normal ACTH and cortisol response to CRH test in three patients. In conclusion, we report that in addition to PTH and TSH resistance, patients with PHP Ia display variable degrees of GHRH resistance, consistent with Gs alpha imprinting in human pituitary.

  3. Early Radio and X-Ray Observations of the Youngest Nearby Type Ia Supernova PTF 11kly (SN 2011fe)

    Science.gov (United States)

    Horesh, Assaf; Kulkarni, S. R.; Fox, Derek B.; Carpenter, John; Kasliwal, Mansi M.; Ofek, Eran O.; Quimby, Robert; Gal-Yam, Avishay; Cenko, S. Bradley; deBruyn, A. G.; hide

    2012-01-01

    On August 24 (UT) the Palomar Transient Factory (PTF) discovered PTF11kly (SN 2011fe), the youngest and most nearby type Ia supernova (SN Ia) in decades. We followed this event up in the radio (centimeter and millimeter bands) and X-ray bands, starting about a day after the estimated explosion time. We present our analysis of the radio and X-ray observations, yielding the tightest constraints yet placed on the pre-explosion mass-loss rate from the progenitor system of this supernova. We find a robust limit of M(raised dot) less than or equal to 10(exp -8) (w /100 kilometers per second ) solar mass yr(exp -1) from sensitive X-ray non-detections, as well as a similar limit from radio data, which depends, however, on assumptions about microphysical parameters. We discuss our results in the context of single-degenerate models for SNe Ia and find that our observations modestly disfavor symbiotic progenitor models involving a red giant donor, but cannot constrain systems accreting from main sequence or sub-giant stars, including the popular supersoft channel. In view of the proximity of PTF11kly and the sensitivity of our prompt observations we would have to wait for a long time (decade or longer) in order to more meaningfully probe the circumstellar matter of Ia supernovae.

  4. Ticking Stellar Time Bomb Identified - Astronomers find prime suspect for a Type Ia supernova

    Science.gov (United States)

    2009-11-01

    Using ESO's Very Large Telescope and its ability to obtain images as sharp as if taken from space, astronomers have made the first time-lapse movie of a rather unusual shell ejected by a "vampire star", which in November 2000 underwent an outburst after gulping down part of its companion's matter. This enabled astronomers to determine the distance and intrinsic brightness of the outbursting object. It appears that this double star system is a prime candidate to be one of the long-sought progenitors of the exploding stars known as Type Ia supernovae, critical for studies of dark energy. "One of the major problems in modern astrophysics is the fact that we still do not know exactly what kinds of stellar system explode as a Type Ia supernova," says Patrick Woudt, from the University of Cape Town and lead author of the paper reporting the results. "As these supernovae play a crucial role in showing that the Universe's expansion is currently accelerating, pushed by a mysterious dark energy, it is rather embarrassing." The astronomers studied the object known as V445 in the constellation of Puppis ("the Stern") in great detail. V445 Puppis is the first, and so far only, nova showing no evidence at all for hydrogen. It provides the first evidence for an outburst on the surface of a white dwarf [1] dominated by helium. "This is critical, as we know that Type Ia supernovae lack hydrogen," says co-author Danny Steeghs, from the University of Warwick, UK, "and the companion star in V445 Pup fits this nicely by also lacking hydrogen, instead dumping mainly helium gas onto the white dwarf." In November 2000, this system underwent a nova outburst, becoming 250 times brighter than before and ejecting a large quantity of matter into space. The team of astronomers used the NACO adaptive optics instrument [2] on ESO's Very Large Telescope (VLT) to obtain very sharp images of V445 Puppis over a time span of two years. The images show a bipolar shell, initially with a very narrow

  5. A Peculiar Subclass of Type Ia Supernovae a.k.a. Type Iax

    Science.gov (United States)

    Singh, Mridweeka; Misra, Kuntal; Sahu, Devendra Kumar; Dastidar, Raya; Gangopadhyay, Anjasha; Bose, Subhash; Srivastav, Shubham; Anapuma, Gadiyara Chakrapani; Chakradhari, Nand Kumar; Kumar, Brajesh; Kumar, Brijesh; Pandey, Shashi Bhushan

    2018-04-01

    We present optical photometric (upto ˜ 410 days since Bmax) and spectroscopic (upto ˜ 235 days since Bmax) observations of a type Iax supernova SN 2014dt located in M61. The broad band light curves follow a linear decline up to ˜ 100 days after which a significant flattening is seen in the late-time (beyond 150 days) light curves of SN 2014dt. SN 2014dt best matches the light curve evolution of SN 2005hk and reaches a peak magnitude of MB˜ -18.12±0.04 with ?m15˜ 1.35±0.06 mag. The earliest spectrum at ˜ 23 days is dominated by FeII and CoII lines with the absence of the Si II 6150 Å line. Using the peak bolometric luminosity we estimate a 56Ni mass of 0.14 M⊙ in the case of SN 2005hk and the striking similarity between SN 2014dt and SN 2005hk implies that a comparable amount of 56Ni would have been synthesized in the explosion of SN 2014dt. There are several explosion scenarios proposed for these peculiar events. Being one of the brightest and closest SN! , SN 2014dt is an ideal candidate for long term monitoring. Late phase observations are very essential to understand the progenitor system and the actual explosion scenario for these events.

  6. Glycogen storage disease type Ia : recent experience with mutation analysis, a summary of mutations reported in the literature and a newly developed diagnostic flowchart

    NARCIS (Netherlands)

    Rake, JP; ten Berge, AM; Visser, G; Verlind, E; Niezen-Koning, KE; Buys, CHCM; Smit, GPA; Scheffer, H

    We studied the glucose-6-phosphatase (G6Pase) gene of 30 unrelated glycogen storage disease type Ia (GSD Ia) patients using single strand conformation, polymorphism (SSCP) prior to automated sequencing of exons revealing an aberrant SSCP pattern. In all patients we could identify mutations on both

  7. On Iron Enrichment, Star Formation, and Type Ia Supernovae in Galaxy Clusters

    Science.gov (United States)

    Loewenstein, Michael

    2006-01-01

    The nature of star formation and Type Ia supernovae (SNIa) in galaxies in the field and in rich galaxy clusters are contrasted by juxtaposing the buildup of heavy metals in the universe inferred from observed star formation and supernovae rate histories with data on the evolution of Fe abundances in the intracluster medium (ICM). Models for the chemical evolution of Fe in these environments are constructed, subject to observational constraints, for this purpose. While models with a mean delay for SNIa of 3 Gyr and standard initial mass function (IMF) are fully consistent with observations in the field, cluster Fe enrichment immediately tracked a rapid, top-heavy phase of star formation - although transport of Fe into the ICM may have been more prolonged and star formation likely continued beyond redshift 1. The means of this prompt enrichment consisted of SNII yielding greater than or equal to 0.1 solar mass per explosion (if the SNIa rate normalization is scaled down from its value in the field according to the relative number of candidate progenitor stars in the 3 - 8 solar mass range) and/or SNIa with short delay times originating during the rapid star formation epoch. Star formation is greater than 3 times more efficient in rich clusters than in the field, mitigating the overcooling problem in numerical cluster simulations. Both the fraction of baryons cycled through stars, and the fraction of the total present-day stellar mass in the form of stellar remnants, are substantially greater in clusters than in the field.

  8. Recombinant human GH replacement therapy in children with pseudohypoparathyroidism type Ia: first study on the effect on growth.

    Science.gov (United States)

    Mantovani, Giovanna; Ferrante, Emanuele; Giavoli, Claudia; Linglart, Agnes; Cappa, Marco; Cisternino, Mariangela; Maghnie, Mohamad; Ghizzoni, Lucia; de Sanctis, Luisa; Lania, Andrea G; Beck-Peccoz, Paolo; Spada, Anna

    2010-11-01

    Since the identification of GH deficiency due to resistance to GHRH in patients with pseudohypoparathyroidism type Ia (PHP-Ia), no study investigated the effects of recombinant human GH (rhGH) therapy on height velocity (HV) in these patients. To address this question, eight prepubertal PHP-Ia children with GH deficiency (seven girls and one boy, aged 5.8-12 yr) underwent a 3- to 8-yr treatment with rhGH. Height and HV were measured before and at 6-month intervals during therapy. Nine sex- and age-matched children with idiopathic GH deficiency were monitored during rhGH therapy for comparison. In PHP-Ia children, height sd scores increased from -2.4 ± 0.58 to -1.8 ± 0.47 (P = 0.04) after 12 months, this increase being maintained after the second (-1.6 ± 0.6) and third (-1.15 ± 0.6) year of therapy, similarly to what recorded in children with idiopathic GH deficiency. The HV and HV sd scores after 3 yr maintained a significant increase from 3.5 ± 0.6 to 7.0 ± 0.9 cm/yr (P pubertal spurt and did not improve their near-adult height, with the only exception of one patient in whom estrogen production was blocked by GnRH analogs. We report the first study on the efficacy of rhGH replacement therapy in prepubertal children with PHP-Ia and provide indication that treatment of GH deficiency should be started soon due to the rather limited time window for a potentially effective therapy.

  9. Hepatic glucose-6-phosphatase-α deficiency leads to metabolic reprogramming in glycogen storage disease type Ia.

    Science.gov (United States)

    Cho, Jun-Ho; Kim, Goo-Young; Mansfield, Brian C; Chou, Janice Y

    2018-04-15

    Glycogen storage disease type Ia (GSD-Ia) is caused by a deficiency in glucose-6-phosphatase-α (G6Pase-α or G6PC), a key enzyme in endogenous glucose production. This autosomal recessive disorder is characterized by impaired glucose homeostasis and long-term complications of hepatocellular adenoma/carcinoma (HCA/HCC). We have shown that hepatic G6Pase-α deficiency-mediated steatosis leads to defective autophagy that is frequently associated with carcinogenesis. We now show that hepatic G6Pase-α deficiency also leads to enhancement of hepatic glycolysis and hexose monophosphate shunt (HMS) that can contribute to hepatocarcinogenesis. The enhanced hepatic glycolysis is reflected by increased lactate accumulation, increased expression of many glycolytic enzymes, and elevated expression of c-Myc that stimulates glycolysis. The increased HMS is reflected by increased glucose-6-phosphate dehydrogenase activity and elevated production of NADPH and the reduced glutathione. We have previously shown that restoration of hepatic G6Pase-α expression in G6Pase-α-deficient liver corrects metabolic abnormalities, normalizes autophagy, and prevents HCA/HCC development in GSD-Ia. We now show that restoration of hepatic G6Pase-α expression normalizes both glycolysis and HMS in GSD-Ia. Moreover, the HCA/HCC lesions in L-G6pc-/- mice exhibit elevated levels of hexokinase 2 (HK2) and the M2 isoform of pyruvate kinase (PKM2) which play an important role in aerobic glycolysis and cancer cell proliferation. Taken together, hepatic G6Pase-α deficiency causes metabolic reprogramming, leading to enhanced glycolysis and elevated HMS that along with impaired autophagy can contribute to HCA/HCC development in GSD-Ia. Published by Elsevier Inc.

  10. THE CRITICAL MASS RATIO OF DOUBLE WHITE DWARF BINARIES FOR VIOLENT MERGER-INDUCED TYPE IA SUPERNOVA EXPLOSIONS

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Yushi [Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Nakasato, Naohito [Department of Computer Science and Engineering, University of Aizu, Tsuruga Ikki-machi Aizu-Wakamatsu, Fukushima 965-8580 (Japan); Tanikawa, Ataru; Hachisu, Izumi [Department of Earth Science and Astronomy, College of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Nomoto, Ken’ichi [Kavli Institute for the Physics and Mathematics of the universe (WPI), The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Maeda, Keiichi, E-mail: sato@ea.c.u-tokyo.ac.jp [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan)

    2016-04-10

    Mergers of carbon–oxygen (CO) white dwarfs (WDs) are considered to be one of the potential progenitors of type Ia supernovae (SNe Ia). Recent hydrodynamical simulations showed that the less massive (secondary) WD violently accretes onto the more massive (primary) one, carbon detonation occurs, the detonation wave propagates through the primary, and the primary finally explodes as a sub-Chandrasekhar mass SN Ia. Such an explosion mechanism is called the violent merger scenario. Based on the smoothed particle hydrodynamics simulations of merging CO WDs, we derived a critical mass ratio (q{sub cr}) leading to the violent merger scenario that is more stringent than previous results. We conclude that this difference mainly comes from the differences in the initial condition of whether or not the WDs are synchronously spinning. Using our new results, we estimated the brightness distribution of SNe Ia in the violent merger scenario and compared it with previous studies. We found that our new q{sub cr} does not significantly affect the brightness distribution. We present the direct outcome immediately following CO WD mergers for various primary masses and mass ratios. We also discussed the final fate of the central system of the bipolar planetary nebula Henize 2-428, which was recently suggested to be a double CO WD system whose total mass exceeds the Chandrasekhar-limiting mass, merging within the Hubble time. Even considering the uncertainties in the proposed binary parameters, we concluded that the final fate of this system is almost certainly a sub-Chandrasekhar mass SN Ia in the violent merger scenario.

  11. MONTE CARLO POPULATION SYNTHESIS OF POST-COMMON-ENVELOPE WHITE DWARF BINARIES AND TYPE Ia SUPERNOVA RATE

    Energy Technology Data Exchange (ETDEWEB)

    Ablimit, Iminhaji [Key Laboratory for Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Maeda, Keiichi [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Li, Xiang-Dong [Department of Astronomy, Nanjing University, Nanjing 210046 (China)

    2016-07-20

    Binary population synthesis (BPS) studies provide a comprehensive way to understand the evolution of binaries and their end products. Close white dwarf (WD) binaries have crucial characteristics for examining the influence of unresolved physical parameters on binary evolution. In this paper, we perform Monte Carlo BPS simulations, investigating the population of WD/main-sequence (WD/MS) binaries and double WD binaries using a publicly available binary star evolution code under 37 different assumptions for key physical processes and binary initial conditions. We considered different combinations of the binding energy parameter ( λ {sub g}: considering gravitational energy only; λ {sub b}: considering both gravitational energy and internal energy; and λ {sub e}: considering gravitational energy, internal energy, and entropy of the envelope, with values derived from the MESA code), CE efficiency, critical mass ratio, initial primary mass function, and metallicity. We find that a larger number of post-CE WD/MS binaries in tight orbits are formed when the binding energy parameters are set by λ {sub e} than in those cases where other prescriptions are adopted. We also determine the effects of the other input parameters on the orbital periods and mass distributions of post-CE WD/MS binaries. As they contain at least one CO WD, double WD systems that evolved from WD/MS binaries may explode as type Ia supernovae (SNe Ia) via merging. In this work, we also investigate the frequency of two WD mergers and compare it to the SNe Ia rate. The calculated Galactic SNe Ia rate with λ = λ {sub e} is comparable to the observed SNe Ia rate, ∼8.2 × 10{sup 5} yr{sup 1} – ∼4 × 10{sup 3} yr{sup 1} depending on the other BPS parameters, if a DD system does not require a mass ratio higher than ∼0.8 to become an SNe Ia. On the other hand, a violent merger scenario, which requires the combined mass of two CO WDs ≥ 1.6 M {sub ⊙} and a mass ratio >0.8, results in a much lower

  12. Spitzer observations of the type IA supernova remnant N103B: Kepler's older cousin?

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Brian J. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Borkowski, Kazimierz J.; Reynolds, Stephen P. [Physics Department, North Carolina State University, Raleigh, NC 27695-8202 (United States); Ghavamian, Parviz [Department of Physics, Chemistry, and Geosciences, Towson University, Towson, MD 21252 (United States); Raymond, John C. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Long, Knox S. [STScI, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Blair, William P. [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218-2686 (United States); Sankrit, Ravi [SOFIA Science Center, NASA AMES Research Center, M/S N211-3, Moffett Field, CA 94035 (United States); Winkler, P. Frank [Department of Physics, Middlebury College, Middlebury, VT 05753 (United States); Hendrick, Sean P., E-mail: brian.j.williams@nasa.gov [Physics Department, Millersville University, P.O. Box 1002, Millersville, PA 17551 (United States)

    2014-08-01

    We report results from Spitzer observations of SNR 0509-68.7, also known as N103B, a young Type Ia supernova remnant (SNR) in the Large Magellanic Cloud (LMC) that shows interaction with a dense medium in its western hemisphere. Our images show that N103B has strong IR emission from warm dust in the post-shock environment. The post-shock gas density we derive, 45 cm{sup –3}, is much higher than in other Type Ia remnants in the LMC, though a lack of spatial resolution may bias measurements toward regions of higher than average density. This density is similar to that in Kepler's SNR, a Type Ia interacting with a circumstellar medium (CSM). Optical images show Hα emission along the entire periphery of the western portion of the shock, with [O III] and [S II] lines emitted from a few dense clumps of material where the shock has become radiative. The dust is silicate in nature, though standard silicate dust models fail to reproduce the '18 μm' silicate feature that peaks instead at 17.3 μm. We propose that the dense material is circumstellar material lost from the progenitor system, as with Kepler. If the CSM interpretation is correct, this remnant would become the second member, along with Kepler, of a class of Type Ia remnants characterized by interaction with a dense CSM hundreds of years post-explosion. A lack of N enhancement eliminates symbiotic asymptotic giant branch progenitors. The white dwarf companion must have been relatively unevolved at the time of the explosion.

  13. Pituitary hypoplasia and growth hormone deficiency in a woman with glycogen storage disease type Ia: a case report

    Directory of Open Access Journals (Sweden)

    Dagdelen Selcuk

    2008-06-01

    Full Text Available Abstract Introduction Growth retardation is one of the cardinal manifestations of glycogen storage disease type Ia. It is unclear which component of the growth hormone and/or insulin-like growth factor axis is primarily disrupted, and management of growth impairment in these patients remains controversial. Here we report the first case in the literature where glycogen storage disease type Ia is associated with pituitary hypoplasia and growth hormone deficiency. Case presentation A 20-year-old woman with glycogen storage disease type Ia was admitted to our endocrinology department because of growth retardation. Basal and overnight growth hormone sampling at 2-hour intervals demonstrated low levels; however, provocative testing revealed a relatively normal growth hormone response. A hypoplastic anterior pituitary with preserved growth hormone response to provocative testing suggested the possibility of growth hormone neurosecretory dysfunction and/or primary pituitary involvement. Conclusion Pituitary hypoplasia may result from growth hormone-releasing hormone deficiency, a condition generally known as growth hormone neurosecretory dysfunction. It is an abnormality with a spontaneous and pulsatile secretion pattern, characterized by short stature, growth retardation and normal serum growth hormone response to provocative testing. However, in the case described in this report, a normal although relatively low growth hormone response during insulin tolerance testing and pituitary hypoplasia suggested that primary pituitary involvement or growth hormone neurosecretory dysfunction may occur in glycogen storage disease type Ia. This is a potential cause of growth failure associated with a lower somatotroph mass, and may explain the variable responsiveness to growth hormone replacement therapy in people with glycogen storage disease.

  14. An absence of ex-companion stars in the type Ia supernova remnant SNR 0509-67.5.

    Science.gov (United States)

    Schaefer, Bradley E; Pagnotta, Ashley

    2012-01-11

    A type Ia supernova is thought to begin with the explosion of a white dwarf star. The explosion could be triggered by the merger of two white dwarfs (a 'double-degenerate' origin), or by mass transfer from a companion star (the 'single-degenerate' path). The identity of the progenitor is still controversial; for example, a recent argument against the single-degenerate origin has been widely rejected. One way to distinguish between the double- and single-degenerate progenitors is to look at the centre of a known type Ia supernova remnant to see whether any former companion star is present. A likely ex-companion star for the progenitor of the supernova observed by Tycho Brahe has been identified, but that claim is still controversial. Here we report that the central region of the supernova remnant SNR 0509-67.5 (the site of a type Ia supernova 400 ± 50 years ago, based on its light echo) in the Large Magellanic Cloud contains no ex-companion star to a visual magnitude limit of 26.9 (an absolute magnitude of M(V) = +8.4) within a region of radius 1.43 arcseconds. (This corresponds to the 3σ maximum distance to which a companion could have been 'kicked' by the explosion.) This lack of any ex-companion star to deep limits rules out all published single-degenerate models for this supernova. The only remaining possibility is that the progenitor of this particular type Ia supernova was a double-degenerate system.

  15. Type Ia Supernova Distances at Redshift >1.5 from the Hubble Space Telescope Multi-cycle Treasury Programs: The Early Expansion Rate

    Science.gov (United States)

    Riess, Adam G.; Rodney, Steven A.; Scolnic, Daniel M.; Shafer, Daniel L.; Strolger, Louis-Gregory; Ferguson, Henry C.; Postman, Marc; Graur, Or; Maoz, Dan; Jha, Saurabh W.; Mobasher, Bahram; Casertano, Stefano; Hayden, Brian; Molino, Alberto; Hjorth, Jens; Garnavich, Peter M.; Jones, David O.; Kirshner, Robert P.; Koekemoer, Anton M.; Grogin, Norman A.; Brammer, Gabriel; Hemmati, Shoubaneh; Dickinson, Mark; Challis, Peter M.; Wolff, Schuyler; Clubb, Kelsey I.; Filippenko, Alexei V.; Nayyeri, Hooshang; Vivian, U.; Koo, David C.; Faber, Sandra M.; Kocevski, Dale; Bradley, Larry; Coe, Dan

    2018-02-01

    We present an analysis of 15 Type Ia supernovae (SNe Ia) at redshift z> 1 (9 at 1.5Ia with a new compilation of ∼1050 SNe Ia, jointly calibrated and corrected for simulated survey biases to produce accurate distance measurements. We present unbiased constraints on the expansion rate at six redshifts in the range 0.07Ia sample. The added leverage of our new sample at z> 1.5 leads to a factor of ∼3 improvement in the determination of the expansion rate at z = 1.5, reducing its uncertainty to ∼20%, a measurement of H(z=1.5)/{H}0 = {2.69}-0.52+0.86. We then demonstrate that these six derived expansion rate measurements alone provide a nearly identical characterization of dark energy as the full SN sample, making them an efficient compression of the SN Ia data. The new sample of SNe Ia at z> 1.5 usefully distinguishes between alternative cosmological models and unmodeled evolution of the SN Ia distance indicators, placing empirical limits on the latter. Finally, employing a realistic simulation of a potential Wide-Field Infrared Survey Telescope SN survey observing strategy, we forecast optimistic future constraints on the expansion rate from SNe Ia.

  16. Spectroscopic Properties of Star-Forming Host Galaxies and Type Ia Supernova Hubble Residuals in a Nearly Unbiased Sample

    Energy Technology Data Exchange (ETDEWEB)

    D' Andrea, Chris B. [Univ. of Pennsylvania, Philadelphia, PA (United States); et al.

    2011-12-20

    We examine the correlation between supernova host galaxy properties and their residuals on the Hubble diagram. We use supernovae discovered during the Sloan Digital Sky Survey II - Supernova Survey, and focus on objects at a redshift of z < 0.15, where the selection effects of the survey are known to yield a complete Type Ia supernova sample. To minimize the bias in our analysis with respect to measured host-galaxy properties, spectra were obtained for nearly all hosts, spanning a range in magnitude of -23 < M_r < -17. In contrast to previous works that use photometric estimates of host mass as a proxy for global metallicity, we analyze host-galaxy spectra to obtain gas-phase metallicities and star-formation rates from host galaxies with active star formation. From a final sample of ~ 40 emission-line galaxies, we find that light-curve corrected Type Ia supernovae are ~ 0.1 magnitudes brighter in high-metallicity hosts than in low-metallicity hosts. We also find a significant (> 3{\\sigma}) correlation between the Hubble residuals of Type Ia supernovae and the specific star-formation rate of the host galaxy. We comment on the importance of supernova/host-galaxy correlations as a source of systematic bias in future deep supernova surveys.

  17. A Measurement of the Rate of Type Ia Supernovae in Galaxy Clusters from the SDSS-II Supernova Survey

    Energy Technology Data Exchange (ETDEWEB)

    Dilday, Benjamin; /Rutgers U., Piscataway /Chicago U. /KICP, Chicago; Bassett, Bruce; /Cape Town U., Dept. Math. /South African Astron. Observ.; Becker, Andrew; /Washington U., Seattle, Astron. Dept.; Bender, Ralf; /Munich, Tech. U. /Munich U. Observ.; Castander, Francisco; /Barcelona, IEEC; Cinabro, David; /Wayne State U.; Frieman, Joshua A.; /Chicago U. /Fermilab; Galbany, Lluis; /Barcelona, IFAE; Garnavich, Peter; /Notre Dame U.; Goobar, Ariel; /Stockholm U., OKC /Stockholm U.; Hopp, Ulrich; /Munich, Tech. U. /Munich U. Observ. /Tokyo U.

    2010-03-01

    We present measurements of the Type Ia supernova (SN) rate in galaxy clusters based on data from the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey. The cluster SN Ia rate is determined from 9 SN events in a set of 71 C4 clusters at z {le} 0.17 and 27 SN events in 492 maxBCG clusters at 0.1 {le} z {le} 0.3. We find values for the cluster SN Ia rate of (0.37{sub -0.12-0.01}{sup +0.17+0.01}) SNur h{sup 2} and (0.55{sub -0.11-0.01}{sup +0.13+0.02}) SNur h{sup 2} (SNux = 10{sup -12}L{sub x{circle_dot}}{sup -1} yr{sup -1}) in C4 and maxBCG clusters, respectively, where the quoted errors are statistical and systematic, respectively. The SN rate for early-type galaxies is found to be (0.31{sub -0.12-0.01}{sup +0.18+0.01}) SNur h{sup 2} and (0.49{sub -0.11-0.01}{sup +0.15+0.02}) SNur h{sup 2} in C4 and maxBCG clusters, respectively. The SN rate for the brightest cluster galaxies (BCG) is found to be (2.04{sub -1.11-0.04}{sup +1.99+0.07}) SNur h{sup 2} and (0.36{sub -0.30-0.01}{sup +0.84+0.01}) SNur h{sup 2} in C4 and maxBCG clusters, respectively. The ratio of the SN Ia rate in cluster early-type galaxies to that of the SN Ia rate in field early-type galaxies is 1.94{sub -0.91-0.015}{sup +1.31+0.043} and 3.02{sub -1.03-0.048}{sup +1.31+0.062}, for C4 and maxBCG clusters, respectively. The SN rate in galaxy clusters as a function of redshift, which probes the late time SN Ia delay distribution, shows only weak dependence on redshift. Combining our current measurements with previous measurements, we fit the cluster SN Ia rate data to a linear function of redshift, and find r{sub L} = [(0.49{sub -0.14}{sup +0.15}) + (0.91{sub -0.81}{sup +0.85}) x z] SNuB h{sup 2}. A comparison of the radial distribution of SNe in cluster to field early-type galaxies shows possible evidence for an enhancement of the SN rate in the cores of cluster early-type galaxies. With an observation of at most 3 hostless, intra-cluster SNe Ia, we estimate the fraction of cluster SNe that are

  18. THE MEAN TYPE IA SUPERNOVA SPECTRUM OVER THE PAST NINE GIGAYEARS

    International Nuclear Information System (INIS)

    Sullivan, M.; Ellis, R. S.; Howell, D. A.; Riess, A.; Nugent, P. E.; Gal-Yam, A.

    2009-01-01

    We examine the possibility of evolution with redshift in the mean rest-frame ultraviolet (UV; λ ∼ H and Kand Mg II blends, indicating lower IME abundances in the higher redshift SNe. A larger fraction of luminous, wider light-curve width (higher s tretch ) SNe Ia are expected at higher redshift than locally, so we compare our observed spectral evolution with that predicted by a redshift-evolving stretch distribution coupled with a stretch-dependent SN Ia spectrum. We show that the sense of the spectral evolution can be reproduced by this simple model, though the highest redshift events seem additionally deficient in Si and Ca. We also examine the mean SN Ia UV-optical colors as a function of redshift, thought to be sensitive to variations in progenitor composition. We find that the expected stretch variations are sufficient to explain the differences, although improved data at z ∼ 0 will enable more precise tests. Thus, to the extent possible with the available data sets, our results support the continued use of SNe Ia as standardized candles.

  19. The First Maximum-light Ultraviolet through Near-infrared Spectrum of a Type Ia Supernova

    DEFF Research Database (Denmark)

    Foley, Ryan J.; Kromer, Markus; Howie Marion, G.

    2012-01-01

    strong constraints on the composition of the SN ejecta, and similarly the SN explosion and progenitor system. SN 2011iv is spectroscopically normal, but has a relatively fast decline (Δm 15(B) = 1.69 ± 0.05 mag). We compare SN 2011iv to other SNe Ia with UV spectra near maximum light and examine trends...

  20. Type Ia Supernovae as Sites of the p-process: Two-dimensional Models Coupled to Nucleosynthesis

    Science.gov (United States)

    Travaglio, C.; Röpke, F. K.; Gallino, R.; Hillebrandt, W.

    2011-10-01

    Beyond Fe, there is a class of 35 proton-rich nuclides, between 74Se and 196Hg, called p-nuclei. They are bypassed by the s and r neutron capture processes and are typically 10-1000 times less abundant than the s- and/or r-isotopes in the solar system. The bulk of p-isotopes is created in the "gamma processes" by sequences of photodisintegrations and beta decays in explosive conditions in both core collapse supernovae (SNe II) and in Type Ia supernovae (SNe Ia). SNe II contribute to the production of p-nuclei through explosive neon and oxygen burning. However, the major problem in SN II ejecta is a general underproduction of the light p-nuclei for A explosive nucleosynthesis with a detailed nuclear reaction network for all isotopes up to 209Bi. We select tracers within the typical temperature range for p-process production, (1.5-3.7) × 109 K, and analyze in detail their behavior, exploring the influence of different s-process distributions on the p-process nucleosynthesis. In addition, we discuss the sensitivity of p-process production to parameters of the explosion mechanism, taking into account the consequences on Fe and alpha elements. We find that SNe Ia can produce a large amount of p-nuclei, both the light p-nuclei below A = 120 and the heavy-p nuclei, at quite flat average production factors, tightly related to the s-process seed distribution. For the first time, we find a stellar source able to produce both light and heavy p-nuclei almost at the same level as 56Fe, including the debated neutron magic 92, 94Mo and 96, 98Ru. We also find that there is an important contribution from the p-process nucleosynthesis to the s-only nuclei 80Kr, 86Sr, to the neutron magic 90Zr, and to the neutron-rich 96Zr. Finally, we investigate the metallicity effect on p-process production in our models. Starting with different s-process seed distributions for two metallicities Z = 0.02 and Z = 0.001, running two-dimensional SN Ia models with different initial composition, we

  1. Homogénéité mutationnelle de la glycogénose de type Ia en Tunisie.

    Science.gov (United States)

    Cherif, W; Rhouma, F Ben; Chehida, A Ben; Azzouz, H; Monastiri, K; Amri, F; Chemli, J; Kaabachi, N; Abdelhak, S; Tebib, N; Dridi, M-F Ben

    2011-08-01

    The glycogen storage disease type Ia (GSD Ia) is a rare inherited disorder, with autosomal recessive determinism. It is characterized by hepatomegaly, short stature and hypoglycemia with lactic acidemia. The confirmation of diagnosis is based on the enzymatic assay performed on liver biopsy. For Tunisians patients, this biochemical test is performed abroad. The aim of our study is the molecular characterization of GSD Ia in Tunisian patients and the development of a molecular diagnosis tool. Our study included 27 patients from 23 unrelated families, mutation analysis revealed that the R83C mutation is the most frequent (65%, 30/46 mutant alleles), followed by the R170Q mutation (30%, 14/46 mutant alleles). The homogeneity of mutation spectrum of GSD Ia in Tunisia allows the development of a cost effective and reliable tool for the confirmation of clinical diagnosis among suspected GSD Ia patients. Copyright © 2009. Published by Elsevier SAS.

  2. Correlations Between Hubble Residuals and MCMC Estimated Local Stellar Ages of Type Ia Supernovae

    Science.gov (United States)

    Rose, Benjamin; Garnavich, Peter

    2018-01-01

    There appears to be correlations between SN Ia Hubble diagram residuals and host galaxy mass, metallicity, and star formation history. An uncorrected bias may produce a systematic offset in cosmological measurements. Global properties are the luminosity average of local environments, therefore the properties of local environments may hold stronger correlations than their global counterparts. There have been previous attempts at finding correlations between local environment properties and Hubble residuals, but nothing without contention has been seen. Looking at the host information from the SDSS Scene Modeling data, we use MCMC to constrain the properties of the stellar population using Flexible Stellar Population Synthesis. We estimate the stellar population's age and star formation history at each resolution element of the galaxy image. The stellar population properties are then compared to the SN Ia properties including the Hubble residuals in the search for correlations that could lead to any systematic bias.

  3. IMPACT OF NEW GAMOW–TELLER STRENGTHS ON EXPLOSIVE TYPE IA SUPERNOVA NUCLEOSYNTHESIS

    Energy Technology Data Exchange (ETDEWEB)

    Mori, Kanji; Famiano, Michael A.; Kajino, Toshitaka; Suzuki, Toshio [National Astronomical Observatory of Japan 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Hidaka, Jun [Mechanical Engineering Department, Meisei University, 2-1-1 Hodokubo, Hino, Tokyo 191-8506 (Japan); Honma, Michio [Center for Mathematical Sciences, University of Aizu, Aizu-Wakamatsu, Fukushima 965-8580 (Japan); Iwamoto, Koichi [Department of Physics, College of Science and Technology, Nihon University, Tokyo 101-8308 (Japan); Nomoto, Ken’ichi [Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo, Kashiwa, Chiba 277-8583 (Japan); Otsuka, Takaharu, E-mail: kanji.mori@nao.ac.jp, E-mail: kajino@nao.ac.jp, E-mail: michael.famiano@wmich.edu, E-mail: suzuki@phys.chs.nihon-u.ac.jp, E-mail: jun.hidaka@meisei-u.ac.jp, E-mail: m-honma@u-aizu.ac.jp, E-mail: iwamoto@phys.cst.nihon-u.ac.jp, E-mail: nomoto@astron.s.u-tokyo.ac.jp, E-mail: otsuka@phys.s.u-tokyo.ac.jp [Department of Physics, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2016-12-20

    Recent experimental results have confirmed a possible reduction in the Gamow–Teller (GT{sub +}) strengths of pf-shell nuclei. These proton-rich nuclei are of relevance in the deflagration and explosive burning phases of SNe Ia. While prior GT strengths result in nucleosynthesis predictions with a lower-than-expected electron fraction, a reduction in the GT{sub +} strength can result in a slightly increased electron fraction compared to previous shell model predictions, though the enhancement is not as large as previous enhancements in going from rates computed by Fuller, Fowler, and Newman based on an independent particle model. A shell model parametrization has been developed that more closely matches experimental GT strengths. The resultant electron-capture rates are used in nucleosynthesis calculations for carbon deflagration and explosion phases of SNe Ia, and the final mass fractions are compared to those obtained using more commonly used rates.

  4. Molecular genetic analysis and phenotypic characteristics of a consanguineous family with glycogen storage disease type Ia.

    Science.gov (United States)

    Lu, Yili; Wang, Liyin; Li, Jun; Wu, Beibei; Wu, Huiping; Luo, Yue; Jin, Zi-Bing; Shan, Xiaoou

    2016-10-01

    Glycogen storage disease type‑Ia (GSD‑Ia) is a rare autosomal recessive disease caused by a mutation in the gene encoding glucose‑6‑phosphate‑α (G6PC). The present study reported the case of a 3‑month‑old female Chinese patient with GSD‑Ia born to consanguineous parents. The aim of the present study was to identify the precise mutation of the G6PC gene associated with this family and to describe the phenotypic characteristics of the patient. A comprehensive examination was performed on the patient, including physical examination, vein blood gas analysis, abdominal sonography and biochemical analyses. In addition, gene sequencing was performed on the coding region of the G6PC gene to identify the mutation. The patient was diagnosed with GSD‑Ia and a G6PC missense mutation of c.518T>C (p.L173P) located in a highly conserved area was identified. The mutation is in a non‑helical region of the protein, which previous studies have suggested should result in a lesser effect on G6PC enzymatic activity and milder phenotypic characteristics compared with mutations located in helical regions. However, the severity of the disease phenotype in the subject of the present study was inconsistent with that predicted from her genotype. The patient suffered from serious hypoglycemia, lactic acidosis, increased triglycerides, hepatic dysfunction, clear hepatomegaly and nephromegaly. The incidence of the p.L173P mutation may be relatively high in the Chinese population. Knowledge of the various phenotypic presentations of the p.L173P mutation may beneficial for future investigations.

  5. VizieR Online Data Catalog: YJK for Type Ia supernovae (Dhawan+, 2015)

    Science.gov (United States)

    Dhawan, S.; Leibundgut, B.; Spyromilio, J.; Maguire, K.

    2015-09-01

    We investigate a large sample of nearby objects with well-sampled optical and NIR data (Table 1). The main data source of NIR SN Ia photometry is the Carnegie SN Project (CSP; Contreras et al., 2010, Cat. J/AJ/139/519; Burns et al. 2011AJ....141...19B, 2014ApJ...789...32B; Stritzinger et al., 2011, Cat. J/AJ/142/156; Phillips, 2012PASA...29..434P). The low-redshift CSP provides a sample of SNe Ia with optical and NIR light curves in a homogeneous and well-defined photometric system ( in Vega magnitude system) and thus forms an ideal basis for the evaluation of light-curve properties. CSP relies primarily on SN discoveries from the Lick Observatory SN Search (Leaman et al., 2011, Cat. J/MNRAS/412/1419). The CSP has published light curves on a total of 82 SNe Ia of which 70 have photometry in YJHK bands. (6 data files).

  6. Constraints on the Progenitor System of the Type Ia Supernova 2014J from Pre-Explosion Hubble Space Telescope Imaging

    Science.gov (United States)

    Kelly, Patrick L.; Fox, Ori D.; Filippenko, Alexei V.; Cenko, S. Bradley; Prato, Lisa; Schaefer, Gail; Shen, Ken J.; Zheng, WeiKang; Graham, Melissa L.; Tucker, Brad E.

    2014-01-01

    We constrain the properties of the progenitor system of the highly reddened Type Ia supernova (SN Ia) 2014J in Messier 82 (M82; d (is) approx. 3.5 Mpc). We determine the supernova (SN) location using Keck-II K-band adaptive optics images, and we find no evidence for flux from a progenitor system in pre-explosion near-ultraviolet through near-infrared Hubble Space Telescope (HST) images. Our upper limits exclude systems having a bright red giant companion, including symbiotic novae with luminosities comparable to that of RS Ophiuchi. While the flux constraints are also inconsistent with predictions for comparatively cool He-donor systems (T (is) approximately 35,000 K), we cannot preclude a system similar to V445 Puppis. The progenitor constraints are robust across a wide range of RV and AV values, but significantly greater values than those inferred from the SN light curve and spectrum would yield proportionally brighter luminosity limits. The comparatively faint flux expected from a binary progenitor system consisting of white dwarf stars would not have been detected in the pre-explosion HST imaging. Infrared HST exposures yield more stringent constraints on the luminosities of very cool (T (is) less than 3000 K) companion stars than was possible in the case of SN Ia 2011fe.

  7. THE HUBBLE SPACE TELESCOPE CLUSTER SUPERNOVA SURVEY. III. CORRELATED PROPERTIES OF TYPE Ia SUPERNOVAE AND THEIR HOSTS AT 0.9 < z < 1.46

    Energy Technology Data Exchange (ETDEWEB)

    Meyers, J.; Barbary, K.; Fakhouri, H. K.; Goldhaber, G. [Department of Physics, University of California Berkeley, Berkeley, CA 94720 (United States); Aldering, G.; Faccioli, L.; Hsiao, E. [E.O. Lawrence Berkeley National Lab, 1 Cyclotron Rd., Berkeley, CA 94720 (United States); Barrientos, L. F. [Departmento de Astronomia, Pontificia Universidad Catolica de Chile, Santiago (Chile); Brodwin, M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Dawson, K. S. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Deustua, S.; Fruchter, A. S. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Doi, M.; Ihara, Y. [Institute of Astronomy, Graduate School of Science, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Eisenhardt, P. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Gilbank, D. G. [Department of Physics and Astronomy, University Of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada); Gladders, M. D. [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Gonzalez, A. H. [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States); Hattori, T. [Subaru Telescope, National Astronomical Observatory of Japan, 650 North Aohaku Place, Hilo, HI 96720 (United States); Kashikawa, N., E-mail: jmeyers314@berkeley.edu [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Collaboration: Supernova Cosmology Project; and others

    2012-05-01

    Using the sample of Type Ia supernovae (SNe Ia) discovered by the Hubble Space Telescope (HST) Cluster Supernova Survey and augmented with HST-observed SNe Ia in the Great Observatories Origins Deep Survey (GOODS) fields, we search for correlations between the properties of SNe and their host galaxies at high redshift. We use galaxy color and quantitative morphology to determine the red sequence in 25 clusters and develop a model to distinguish passively evolving early-type galaxies from star-forming galaxies in both clusters and the field. With this approach, we identify 6 SN Ia hosts that are early-type cluster members and 11 SN Ia hosts that are early-type field galaxies. We confirm for the first time at z > 0.9 that SNe Ia hosted by early-type galaxies brighten and fade more quickly than SNe Ia hosted by late-type galaxies. We also show that the two samples of hosts produce SNe Ia with similar color distributions. The relatively simple spectral energy distributions expected for passive galaxies enable us to measure stellar masses of early-type SN hosts. In combination with stellar mass estimates of late-type GOODS SN hosts from Thomson and Chary, we investigate the correlation of host mass with Hubble residual observed at lower redshifts. Although the sample is small and the uncertainties are large, a hint of this relation is found at z > 0.9. By simultaneously fitting the average cluster galaxy formation history and dust content to the red-sequence scatters, we show that the reddening of early-type cluster SN hosts is likely E(B - V) {approx}< 0.06. The similarity of the field and cluster early-type host samples suggests that field early-type galaxies that lie on the red sequence may also be minimally affected by dust. Hence, the early-type-hosted SNe Ia studied here occupy a more favorable environment to use as well-characterized high-redshift standard candles than other SNe Ia.

  8. THE RISE AND FALL OF TYPE Ia SUPERNOVA LIGHT CURVES IN THE SDSS-II SUPERNOVA SURVEY

    International Nuclear Information System (INIS)

    Hayden, Brian T.; Garnavich, Peter M.; Kessler, Richard; Frieman, Joshua A.; Jha, Saurabh W.; Bassett, Bruce; Smith, Mathew; Cinabro, David; Dilday, Benjamin; Kasen, Daniel; Marriner, John; Nichol, Robert C.; Riess, Adam G.; Sako, Masao; Schneider, Donald P.; Sollerman, Jesper

    2010-01-01

    We analyze the rise and fall times of Type Ia supernova (SN Ia) light curves discovered by the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey. From a set of 391 light curves k-corrected to the rest-frame B and V bands, we find a smaller dispersion in the rising portion of the light curve compared to the decline. This is in qualitative agreement with computer models which predict that variations in radioactive nickel yield have less impact on the rise than on the spread of the decline rates. The differences we find in the rise and fall properties suggest that a single 'stretch' correction to the light curve phase does not properly model the range of SN Ia light curve shapes. We select a subset of 105 light curves well observed in both rise and fall portions of the light curves and develop a '2-stretch' fit algorithm which estimates the rise and fall times independently. We find the average time from explosion to B-band peak brightness is 17.38 ± 0.17 days, but with a spread of rise times which range from 13 days to 23 days. Our average rise time is shorter than the 19.5 days found in previous studies; this reflects both the different light curve template used and the application of the 2-stretch algorithm. The SDSS-II supernova set and the local SNe Ia with well-observed early light curves show no significant differences in their average rise-time properties. We find that slow-declining events tend to have fast rise times, but that the distribution of rise minus fall time is broad and single peaked. This distribution is in contrast to the bimodality in this parameter that was first suggested by Strovink from an analysis of a small set of local SNe Ia. We divide the SDSS-II sample in half based on the rise minus fall value, t r - t f ≤ 2 days and t r - t f > 2 days, to search for differences in their host galaxy properties and Hubble residuals; we find no difference in host galaxy properties or Hubble residuals in our sample.

  9. The Rise and Fall of Type Ia Supernova Light Curves in the SDSS-II Supernova Survey

    Energy Technology Data Exchange (ETDEWEB)

    Hayden, Brian T.; /Notre Dame U.; Garnavich, Peter M.; /Notre Dame U.; Kessler, Richard; /KICP, Chicago /Chicago U., EFI; Frieman, Joshua A.; /KICP, Chicago /Chicago U. /Fermilab; Jha, Saurabh W.; /Stanford U., Phys. Dept. /Rutgers U., Piscataway; Bassett, Bruce; /Cape Town U., Dept. Math. /South African Astron. Observ.; Cinabro, David; /Wayne State U.; Dilday, Benjamin; /Rutgers U., Piscataway; Kasen, Daniel; /UC, Santa Cruz; Marriner, John; /Fermilab; Nichol, Robert C.; /Portsmouth U., ICG /Baltimore, Space Telescope Sci. /Johns Hopkins U.

    2010-01-01

    We analyze the rise and fall times of Type Ia supernova (SN Ia) light curves discovered by the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey. From a set of 391 light curves k-corrected to the rest-frame B and V bands, we find a smaller dispersion in the rising portion of the light curve compared to the decline. This is in qualitative agreement with computer models which predict that variations in radioactive nickel yield have less impact on the rise than on the spread of the decline rates. The differences we find in the rise and fall properties suggest that a single 'stretch' correction to the light curve phase does not properly model the range of SN Ia light curve shapes. We select a subset of 105 light curves well observed in both rise and fall portions of the light curves and develop a '2-stretch' fit algorithm which estimates the rise and fall times independently. We find the average time from explosion to B-band peak brightness is 17.38 {+-} 0.17 days, but with a spread of rise times which range from 13 days to 23 days. Our average rise time is shorter than the 19.5 days found in previous studies; this reflects both the different light curve template used and the application of the 2-stretch algorithm. The SDSS-II supernova set and the local SNe Ia with well-observed early light curves show no significant differences in their average rise-time properties. We find that slow-declining events tend to have fast rise times, but that the distribution of rise minus fall time is broad and single peaked. This distribution is in contrast to the bimodality in this parameter that was first suggested by Strovink (2007) from an analysis of a small set of local SNe Ia. We divide the SDSS-II sample in half based on the rise minus fall value, t{sub r} - t{sub f} {approx}< 2 days and t{sub r} - t{sub f} > 2 days, to search for differences in their host galaxy properties and Hubble residuals; we find no difference in host galaxy properties or Hubble

  10. The Cardassian expansion revisited: constraints from updated Hubble parameter measurements and Type Ia Supernovae data

    Science.gov (United States)

    Magaña, Juan; Amante, Mario H.; Garcia-Aspeitia, Miguel A.; Motta, V.

    2018-02-01

    Motivated by an updated compilation of observational Hubble data (OHD) which consist of 51 points in the redshift range 0.07 Ia using the compressed and full joint-light-analysis (JLA) samples. We also perform a joint analysis using the combination OHD plus compressed JLA. Our results show that the OC and MPC models are in agreement with the standard cosmology and naturally introduce a cosmological-constant-like extra term in the canonical Friedmann equation with the capability of accelerating the Universe without dark energy.

  11. Nearby Supernova Factory Observations of SN 2005gj: Another TypeIa Supernova in a Massive Circumstellar Envelope

    Energy Technology Data Exchange (ETDEWEB)

    Aldering, G.; Antilogus, P.; Bailey, S.; Baltay, C.; Bauer, A.; Blanc, N.; Bongard, S.; Copin, Y.; Gangler, E.; Gilles, S.; Kessler, R.; Kocevski, D.; Lee, B.C.; Loken, S.; Nugent, P.; Pain, R.; Pecontal, E.; Pereira, R.; Perlmutter, S.; Rabinowitz, D.; Rigaudier, G.; Scalzo, R.; Smadja, G.; Thomas, R.C.; Wang, L.; Weaver, B.A.; Rabinowitz, D.; Bauer, A.

    2006-06-01

    We report the independent discovery and follow-up observations of supernova 2005gj by the Nearby Supernova Factory. This is the second confirmed case of a ''hybrid'' Type Ia/IIn supernova, which like the prototype SN 2002ic, we interpret as the explosion of a white dwarf interacting with a circumstellar medium. Our early-phase photometry of SN 2005gj shows that the strength of the interaction between the supernova ejecta and circumstellar material is much stronger than for SN 2002ic. Our .rst spectrum shows a hot continuum with broad and narrow H{alpha} emission. Later spectra, spanning over 4 months from outburst, show clear Type Ia features combined with broad and narrow H{gamma}, H{beta},H{alpha} and He I {lambda}{lambda}5876,7065 in emission. At higher resolution, P Cygni profiles are apparent. Surprisingly, we also observe an inverted P Cygni profile for [O III] {lambda}5007. We find that the lightcurve and measured velocity of the unshocked circumstellar material imply mass loss as recently as 8 years ago. This is in contrast to SN 2002ic, for which an inner cavity in the circumstellar material was inferred. Within the context of the thin-shell approximation, the early lightcurve is well-described by a flat radial density profile for the circumstellar material. However, our decomposition of the spectra into Type Ia and shock emission components allows for little obscuration of the supernova, suggesting an aspherical or clumpy distribution for the circumstellar material. We suggest that the emission line velocity profiles arise from electron scattering rather than the kinematics of the shock. This is supported by the inferred high densities, and the lack of evidence for evolution in the line widths. Ground- and space-based photometry, and Keck spectroscopy, of the host galaxy are used to ascertain that the host galaxy has low metallicity (Z/Z{sub {circle_dot}} < 0.3; 95% confidence) and that this galaxy is undergoing a significant star

  12. The Effect of the Pre-Detonation Stellar Internal Velocity Profile on the Nucleosynthetic Yields in Type Ia Supernova

    OpenAIRE

    Kim, Yeunjin; Jordan IV, G. C.; Graziani, Carlo; Meyer, B. S.; Lamb, D. Q.; Truran, J. W.

    2013-01-01

    A common model of the explosion mechanism of Type Ia supernovae is based on a delayed detonation of a white dwarf. A variety of models differ primarily in the method by which the deflagration leads to a detonation. A common feature of the models, however, is that all of them involve the propagation of the detonation through a white dwarf that is either expanding or contracting, where the stellar internal velocity profile depends on both time and space. In this work, we investigate the effects...

  13. Nebular Phase Observations of the Type Ia Supernova 2014J in the Near Infrared

    Science.gov (United States)

    Diamond, Tiara

    2018-01-01

    Late-time spectra of SNe Ia show numerous strong emission features of iron and cobalt throughout the near infrared region. As the spectrum ages, the cobalt features fade as is expected from the decay of 56Co to 56Fe. The strong 1.6440 μm [Fe II] feature is sensitive to the central density of the white dwarf just prior to the runaway because of electron capture in the early stages of burning, hence the line profile width and evolution can be used to probe possible progenitor scenarios. The line profile is dependent on the extent of mixing during any deflagration burning in addition to asymmetries in the distribution of burning products or an off-center ignition. We present observations of SN 2014J from 300–500 days post-explosion. The data are consistent with spherical models of a MCh explosion with a deflagration-to-detonation transition, central density of 0.7×109 g/cm3, and limited mixing. An asymmetry in the line profile of the last spectrum could indicate an off-center ignition or burning products that are not centered on the kinetic center of the explosion. These and other late-time spectroscopic observations in the infrared of a significant sample of SNe Ia will provide insight into the natural variety of these objects, improving our understanding of the underlying physical processes and their usability in cosmology.

  14. Measurements of the Rate of Type Ia Supernovae at Redshift z < ~0.3 from the SDSS-II Supernova Survey

    Energy Technology Data Exchange (ETDEWEB)

    Dilday, Benjamin; /Rutgers U., Piscataway /Chicago U. /KICP, Chicago; Smith, Mathew; /Cape Town U., Dept. Math. /Portsmouth U.; Bassett, Bruce; /Cape Town U., Dept. Math. /South African Astron. Observ.; Becker, Andrew; /Washington U., Seattle, Astron. Dept.; Bender, Ralf; /Munich, Tech. U. /Munich U. Observ.; Castander, Francisco; /Barcelona, IEEC; Cinabro, David; /Wayne State U.; Filippenko, Alexei V.; /UC, Berkeley; Frieman, Joshua A.; /Chicago U. /Fermilab; Galbany, Lluis; /Barcelona, IFAE; Garnavich, Peter M.; /Notre Dame U. /Stockholm U., OKC /Stockholm U.

    2010-01-01

    We present a measurement of the volumetric Type Ia supernova (SN Ia) rate based on data from the Sloan Digital Sky Survey II (SDSS-II) Supernova Survey. The adopted sample of supernovae (SNe) includes 516 SNe Ia at redshift z {approx}< 0.3, of which 270 (52%) are spectroscopically identified as SNe Ia. The remaining 246 SNe Ia were identified through their light curves; 113 of these objects have spectroscopic redshifts from spectra of their host galaxy, and 133 have photometric redshifts estimated from the SN light curves. Based on consideration of 87 spectroscopically confirmed non-Ia SNe discovered by the SDSS-II SN Survey, we estimate that 2.04{sub -0.95}{sup +1.61}% of the photometric SNe Ia may be misidentified. The sample of SNe Ia used in this measurement represents an order of magnitude increase in the statistics for SN Ia rate measurements in the redshift range covered by the SDSS-II Supernova Survey. If we assume a SN Ia rate that is constant at low redshift (z < 0.15), then the SN observations can be used to infer a value of the SN rate of r{sub V} = (2.69{sub -0.30-0.01}{sup +0.34+0.21}) x 10{sup -5} SNe yr{sup -1} Mpc{sup -3} (H{sub 0}/(70 km s{sup -1} Mpc{sup -1})){sup 3} at a mean redshift of {approx} 0.12, based on 79 SNe Ia of which 72 are spectroscopically confirmed. However, the large sample of SNe Ia included in this study allows us to place constraints on the redshift dependence of the SN Ia rate based on the SDSS-II Supernova Survey data alone. Fitting a power-law model of the SN rate evolution, r{sub V} (z) = A{sub p} x ((1+z)/(1+z{sub 0})){sup {nu}}, over the redshift range 0.0 < z < 0.3 with z{sub 0} = 0.21, results in A{sub p} = (3.43{sub -0.15}{sup +0.15}) x 10{sup -5} SNe yr{sup -1} Mpc{sup -3} (H{sub 0}/(70 km s{sup -1} Mpc{sup -1})){sup 3} and {nu} = 2.04{sub -0.89}{sup +0.90}.

  15. Prevention of Hepatocellular Adenoma and Correction of Metabolic Abnormalities in Murine Glycogen Storage Disease Type Ia by Gene Therapy

    Science.gov (United States)

    Lee, Young Mok; Jun, Hyun Sik; Pan, Chi-Jiunn; Lin, Su Ru; Wilson, Lane H.; Mansfield, Brian C.; Chou, Janice Y.

    2012-01-01

    Glycogen storage disease type Ia (GSD-Ia), characterized by impaired glucose homeostasis and chronic risk of hepatocellular adenoma (HCA), is caused by deficiencies in the endoplasmic reticulum (ER)-associated glucose-6-phosphatase-α (G6Pase-α or G6PC) that hydrolyzes glucose-6-phosphate (G6P) to glucose. G6Pase-α activity depends upon the G6P transporter (G6PT) that translocates G6P from the cytoplasm into the ER lumen. The functional coupling of G6Pase-α and G6PT maintains interprandial glucose homeostasis. We have previously shown that gene therapy mediated by AAV-GPE, an adeno-associated virus (AAV) vector expressing G6Pase-α directed by the human G6PC promoter/enhancer (GPE), completely normalizes hepatic G6Pase-α deficiency in GSD-Ia (G6pc−/−) mice for at least 24 weeks. However, a recent study showed that, within 78 weeks of gene deletion, all mice lacking G6Pase-α in the liver develop HCA. We now show that gene therapy mediated by AAV-GPE maintains efficacy for at least 70–90 weeks for mice expressing more than 3% of wild type hepatic G6Pase-α activity. The treated mice displayed normal hepatic fat storage, normal blood metabolite and glucose tolerance profiles, reduced fasting blood insulin levels, maintained normoglycemia over a 24-hour fast, and had no evidence of hepatic abnormalities. After a 24-hour fast, hepatic G6PT mRNA levels in G6pc−/− mice receiving gene therapy were markedly increased. Since G6PT transport is the rate-limiting step in microsomal G6P metabolism it may explain why the treated G6pc−/− mice could sustain prolonged fasts. The low fasting blood insulin levels and lack of hepatic steatosis may explain the absence of HCA. Conclusion These results confirm that AAV-GPE-mediated gene transfer corrects hepatic G6Pase-α deficiency in murine GSD-Ia and prevents chronic HCA formation. PMID:22422504

  16. The KBC Void: Consistency with Supernovae Type Ia and the Kinematic SZ Effect in a ΛLTB Model

    Science.gov (United States)

    Hoscheit, Benjamin L.; Barger, Amy J.

    2018-02-01

    There is substantial and growing observational evidence from the normalized luminosity density in the near-infrared that the local universe is underdense on scales of several hundred megaparsecs. We test whether our parameterization of the observational data of such a “void” is compatible with the latest supernovae type Ia data and with constraints from line-of-sight peculiar-velocity motions of galaxy clusters with respect to the cosmic microwave background rest-frame, known as the linear kinematic Sunyaev–Zel’dovich (kSZ) effect. Our study is based on the large local void (LLV) radial profile observed by Keenan, Barger, and Cowie (KBC) and a theoretical void description based on the Lemaître–Tolman–Bondi model with a nonzero cosmological constant (ΛLTB). We find consistency with the measured luminosity distance–redshift relation on radial scales relevant to the KBC LLV through a comparison with 217 low-redshift supernovae type Ia over the redshift range 0.0233Cosmology Telescope, are fully compatible with the existence of the KBC LLV.

  17. Quantifying the Physics of the Second Maximum in I-band Type Ia Supernova Light Curves for Improved Cosmological Constraints

    Science.gov (United States)

    Foley, Michael; Foley, Ryan; Garnavich, Peter

    2018-01-01

    Type Ia supernovae are important cosmological distance indicators, particularly in the measurement of H_0 and dark energy. Their use relies on the precise fitting of light curves in different bandpass filters to extract intrinsic parameters of the supernova, such as stretch and color. The I-band (infrared) is an important filter in these analyses as luminosity variations and dust extinction are reduced in this band compared to bluer bands. However, the I-band possesses a poorly constrained feature that is not present in bluer bands - a second peak in the supernova light curve that occurs roughly 20-30 days after the first maximum. This limits the effectiveness of light curve fits, forcing analyses to weight against this band. To remedy this, we use data from the Open Supernova Catalog and the Foundation Supernova Survey to determine correlations between the time and magnitude of the second maximum and other known parameters, including peak luminosity, dm15, and ejecta velocity. This work could help improve distance measurements of Type Ia supernovae and provide important information about the physics of the explosion.

  18. Glycogen storage disease type Ia : four novel mutations (175delGG, R170X, G266V and V338F) identified. Mutations in brief no. 220. Online

    NARCIS (Netherlands)

    Rake, J P; ten Berge, A M; Verlind, E; Visser, G; Niezen-Koning, K E; Buys, C H; Smit, G P; Scheffer, H

    1999-01-01

    Deficient activity of glucose-6-phosphatase (G6Pase) causes glycogen storage disease type Ia (GSD Ia). We analysed the G6Pase gene of 16 GSD Ia patients using single strand conformation polymorphism (SSCP) analysis prior to automated sequencing of exon(s) revealing an aberrant SSCP pattern. In all

  19. VizieR Online Data Catalog: Host galaxies of Type Ia SN from PTF (Pan+, 2014)

    Science.gov (United States)

    Pan, Y.-C.; Sullivan, M.; Maguire, K.; Hook, I. M.; Nugent, P. E.; Howell, D. A.; Arcavi, I.; Botyanszki, J.; Cenko, S. B.; Derose, J.; Fakhouri, H. K.; Gal-Yam, A.; Hsiao, E.; Kulkarni, S. R.; Laher, R. R.; Lidman, C.; Nordin, J.; Walker, E. S.; Xu, D.

    2014-11-01

    The SNe Ia studied in this paper were discovered by the PTF, a project which operated from 2009 to 2012 and used the CFH12k wide-field survey camera mounted on the Samuel Oschin 48 inch telescope (P48) at the Palomar Observatory. The observational cadences used to discover the SNe ranged from hours up to ~5d. SN candidates were identified in image subtraction data and ranked using both simple cuts on the detection parameters and a machine learning algorithm (Bloom et al. 2012PASP..124.1175B), and then visually confirmed by members of the PTF collaboration or, from mid-2010 onwards, via the citizen science project 'Galaxy Zoo: Supernova' (Smith et al., 2011MNRAS.412.1309S). The latter identified eight of the SNe studied in this paper. (4 data files).

  20. MID-IR SPECTRA OF TYPE Ia SN 2014J IN M82 SPANNING THE FIRST 4 MONTHS

    Energy Technology Data Exchange (ETDEWEB)

    Telesco, Charles M.; Li, Dan; Barnes, Peter J.; Mariñas, Naibí; Zhang, Han [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States); Höflich, Peter [Department of Physics, Florida State University, Tallahassee, FL 32305 (United States); Álvarez, Carlos; Fernández, Sergio; Rebolo, Rafael [Instituto de Astrofísica de Canarias, C/ Vía Láctea, s/n E-38205 La Laguna (Tenerife) (Spain); Wright, Christopher M. [School of Physical, Environmental and Mathematical Sciences, University of New South Wales, P.O. Box 7916, Canberra BC ACT 2610 (Australia); Hough, James H. [School of Physics, Astronomy and Mathematics, University of Hertfordshire, Hatfield, Hertfordshire, AL10 9AB (United Kingdom); Levenson, N. A. [Gemini Observatory, Casilla 603, c/o AURA, La Serena (Chile); Packham, Christopher [Physics and Astronomy Department, University of Texas at San Antonio, 1 UTSA Circle, San Antonio, TX 78249 (United States); Pantin, Eric [Service d' Astrophysique CEA Saclay (France); Roche, Patrick, E-mail: telesco@astro.ufl.edu, E-mail: phoeflich77@gmail.com [Department of Astrophysics, Oxford University, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom)

    2015-01-10

    We present a time series of 8-13 μm spectra and photometry for SN 2014J obtained 57, 81, 108, and 137 days after the explosion using CanariCam on the Gran Telescopio Canarias. This is the first mid-IR time series ever obtained for a Type Ia supernova (SN Ia). These observations can be understood within the framework of the delayed detonation model and the production of ∼0.6 M {sub ☉} of {sup 56}Ni, consistent with the observed brightness, the brightness decline relation, and the γ-ray fluxes. The [Co III] line at 11.888 μm is particularly useful for evaluating the time evolution of the photosphere and measuring the amount of {sup 56}Ni and thus the mass of the ejecta. Late-time line profiles of SN 2014J are rather symmetric and not shifted in the rest frame. We see argon emission, which provides a unique probe of mixing in the transition layer between incomplete burning and nuclear statistical equilibrium. We may see [Fe III] and [Ni IV] emission, both of which are observed to be substantially stronger than indicated by our models. If the latter identification is correct, then we are likely observing stable Ni, which might imply central mixing. In addition, electron capture, also required for stable Ni, requires densities larger than ∼1 × 10{sup 9} g cm{sup –3}, which are expected to be present only in white dwarfs close to the Chandrasekhar limit. This study demonstrates that mid-IR studies of SNe Ia are feasible from the ground and provide unique information, but it also indicates the need for better atomic data.

  1. On the Time Variation of Dust Extinction and Gas Absorption for Type Ia Supernovae Observed Through Non-uniform Interstellar Medium

    Science.gov (United States)

    Huang, Xiaosheng; Aldering, Gregory; Biederman, Moriah; Herger, Brendan

    2018-01-01

    For Type Ia supernovae (SNe Ia) observed through a non-uniform interstellar medium (ISM) in its host galaxy, we investigate whether the non-uniformity can cause observable time variations in dust extinction and in gas absorption due to the expansion of the SN photosphere with time. We show that, owing to the steep spectral index of the ISM density power spectrum, sizable density fluctuation amplitudes at the length scale of typical ISM structures (>~ 10 pc) will translate to much smaller fluctuations on the scales of a SN photosphere. Therefore the typical amplitude of time variation due to non-uniform ISM, of absorption equivalent widths and of extinction, would be small. As a result, we conclude that non-uniform ISM density should not impact cosmology measurements based on SNe Ia. We apply our predictions based on the ISM density power law power spectrum to the observations of two highly reddened SNe Ia, SN 2012cu and SN 2014J.

  2. Multidimensional Models of Type Ia Supernova Nebular Spectra: Strong Emission Lines from Stripped Companion Gas Rule Out Classic Single-degenerate Systems

    Science.gov (United States)

    Botyánszki, János; Kasen, Daniel; Plewa, Tomasz

    2018-01-01

    The classic single-degenerate model for the progenitors of Type Ia supernova (SN Ia) predicts that the supernova ejecta should be enriched with solar-like abundance material stripped from the companion star. Spectroscopic observations of normal SNe Ia at late times, however, have not resulted in definite detection of hydrogen. In this Letter, we study line formation in SNe Ia at nebular times using non-LTE spectral modeling. We present, for the first time, multidimensional radiative transfer calculations of SNe Ia with stripped material mixed in the ejecta core, based on hydrodynamical simulations of ejecta–companion interaction. We find that interaction models with main-sequence companions produce significant Hα emission at late times, ruling out these types of binaries being viable progenitors of SNe Ia. We also predict significant He I line emission at optical and near-infrared wavelengths for both hydrogen-rich or helium-rich material, providing an additional observational probe of stripped ejecta. We produce models with reduced stripped masses and find a more stringent mass limit of M st ≲ 1 × 10‑4 M ⊙ of stripped companion material for SN 2011fe.

  3. Fitting and Phenomenology in Type IA Supernova Cosmology: Generalized Likelihood Analyses for Multiple Evolving Populations and Observations of Near-Infrared Lightcurves Including Host Galaxy Properties

    Science.gov (United States)

    Ponder, Kara A.

    In the late 1990s, Type Ia supernovae (SNeIa) led to the discovery that the Universe is expanding at an accelerating rate due to dark energy. Since then, many different tracers of acceleration have been used to characterize dark energy, but the source of cosmic acceleration has remained a mystery. To better understand dark energy, future surveys such as the ground-based Large Synoptic Survey Telescope and the space-based Wide-Field Infrared Survey Telescope will collect thousands of SNeIa to use as a primary dark energy probe. These large surveys will be systematics limited, which makes it imperative for our insight regarding systematics to dramatically increase over the next decade for SNeIa to continue to contribute to precision cosmology. I approach this problem by improving statistical methods in the likelihood analysis and collecting near infrared (NIR) SNeIa with their host galaxies to improve the nearby data set and search for additional systematics. Using more statistically robust methods to account for systematics within the likelihood function can increase accuracy in cosmological parameters with a minimal precision loss. Though a sample of at least 10,000 SNeIa is necessary to confirm multiple populations of SNeIa, the bias in cosmology is ˜ 2 sigma with only 2,500 SNeIa. This work focused on an example systematic (host galaxy correlations), but it can be generalized for any systematic that can be represented by a distribution of multiple Gaussians. The SweetSpot survey gathered 114 low-redshift, NIR SNeIa that will act as a crucial anchor sample for the future high redshift surveys. NIR observations are not as affected by dust contamination, which may lead to increased understanding of systematics seen in optical wavelengths. We obtained spatially resolved spectra for 32 SweetSpot host galaxies to test for local host galaxy correlations. For the first time, we probe global host galaxy correlations with NIR brightnesses from the current literature

  4. H0 from cosmic chronometers and Type Ia supernovae, with Gaussian Processes and the novel Weighted Polynomial Regression method

    Science.gov (United States)

    Gómez-Valent, Adrià; Amendola, Luca

    2018-04-01

    In this paper we present new constraints on the Hubble parameter H0 using: (i) the available data on H(z) obtained from cosmic chronometers (CCH); (ii) the Hubble rate data points extracted from the supernovae of Type Ia (SnIa) of the Pantheon compilation and the Hubble Space Telescope (HST) CANDELS and CLASH Multy-Cycle Treasury (MCT) programs; and (iii) the local HST measurement of H0 provided by Riess et al. (2018), H0HST=(73.45±1.66) km/s/Mpc. Various determinations of H0 using the Gaussian processes (GPs) method and the most updated list of CCH data have been recently provided by Yu, Ratra & Wang (2018). Using the Gaussian kernel they find H0=(67.42± 4.75) km/s/Mpc. Here we extend their analysis to also include the most released and complete set of SnIa data, which allows us to reduce the uncertainty by a factor ~ 3 with respect to the result found by only considering the CCH information. We obtain H0=(67.06± 1.68) km/s/Mpc, which favors again the lower range of values for H0 and is in tension with H0HST. The tension reaches the 2.71σ level. We round off the GPs determination too by taking also into account the error propagation of the kernel hyperparameters when the CCH with and without H0HST are used in the analysis. In addition, we present a novel method to reconstruct functions from data, which consists in a weighted sum of polynomial regressions (WPR). We apply it from a cosmographic perspective to reconstruct H(z) and estimate H0 from CCH and SnIa measurements. The result obtained with this method, H0=(68.90± 1.96) km/s/Mpc, is fully compatible with the GPs ones. Finally, a more conservative GPs+WPR value is also provided, H0=(68.45± 2.00) km/s/Mpc, which is still almost 2σ away from H0HST.

  5. SPECTROSCOPIC OBSERVATIONS OF SN 2012fr: A LUMINOUS, NORMAL TYPE Ia SUPERNOVA WITH EARLY HIGH-VELOCITY FEATURES AND A LATE VELOCITY PLATEAU

    International Nuclear Information System (INIS)

    Childress, M. J.; Scalzo, R. A.; Sim, S. A.; Tucker, B. E.; Yuan, F.; Schmidt, B. P.; Cenko, S. B.; Filippenko, A. V.; Silverman, J. M.; Contreras, C.; Hsiao, E. Y.; Phillips, M.; Morrell, N.; Jha, S. W.; McCully, C.; Anderson, J. P.; De Jaeger, T.; Forster, F.; Benetti, S.; Bufano, F.

    2013-01-01

    We present 65 optical spectra of the Type Ia SN 2012fr, 33 of which were obtained before maximum light. At early times, SN 2012fr shows clear evidence of a high-velocity feature (HVF) in the Si II λ6355 line that can be cleanly decoupled from the lower velocity ''photospheric'' component. This Si II λ6355 HVF fades by phase –5; subsequently, the photospheric component exhibits a very narrow velocity width and remains at a nearly constant velocity of ∼12,000 km s –1 until at least five weeks after maximum brightness. The Ca II infrared triplet exhibits similar evidence for both a photospheric component at v ≈ 12,000 km s –1 with narrow line width and long velocity plateau, as well as an HVF beginning at v ≈ 31,000 km s –1 two weeks before maximum. SN 2012fr resides on the border between the ''shallow silicon'' and ''core-normal'' subclasses in the Branch et al. classification scheme, and on the border between normal and high-velocity Type Ia supernovae (SNe Ia) in the Wang et al. system. Though it is a clear member of the ''low velocity gradient'' group of SNe Ia and exhibits a very slow light-curve decline, it shows key dissimilarities with the overluminous SN 1991T or SN 1999aa subclasses of SNe Ia. SN 2012fr represents a well-observed SN Ia at the luminous end of the normal SN Ia distribution and a key transitional event between nominal spectroscopic subclasses of SNe Ia.

  6. Arthroscopic Partial Capitate Resection for Type Ia Avascular Necrosis: A Short-Term Outcome Analysis.

    Science.gov (United States)

    Shimizu, Takamasa; Omokawa, Shohei; del Piñal, Francisco; Shigematsu, Koji; Moritomo, Hisao; Tanaka, Yasuhito

    2015-12-01

    To examine short-term clinical results of arthroscopic partial resection for type Ia avascular necrosis of the capitate. Patients who underwent arthroscopic treatment for type 1a avascular necrosis of the capitate with at least 1-year follow-up were identified through a retrospective chart review. The necrotic capitate head was arthroscopically resected with removal of the lunate facet and preservation of the scaphoid and hamate facets. Wrist range of motion, grip strength, and radiographic parameters--carpal height ratio, radioscaphoid angle, and radiolunate angle-were determined before surgery and at the latest follow-up. Patients completed a visual analog scale for pain; Disabilities of the Arm, Shoulder, and Hand measure; and the Patient-Rated Wrist Evaluation score before surgery and at the latest follow-up. Five patients (1 male, 4 females) with a mean age of 34 years (range, 16-49 years) and a mean follow-up duration of 20 months (range, 12-36 months) were identified during the chart review. All were type Ia (Milliez classification). Arthroscopy revealed fibrillation or softening with cartilage detachment at the lunate facet of the capitate head and an intact articular surface at the scaphoid and hamate facet. At the latest follow-up, the mean wrist flexion-extension was 123° (vs 81° before surgery) and grip strength was 74% (vs 37% before surgery). The visual analog scale score for pain; the Disabilities of the Arm, Shoulder, and Hand score; and the Patient-Rated Wrist Evaluation score before surgery showed a significant improvement following treatment. Radiographic parameters did not significantly change at the final follow-up, although the proximal carpal row trended toward flexion. Arthroscopic partial resection of the capitate head was an acceptable treatment for type Ia avascular necrosis of the capitate. It provided adequate pain relief and improved the range of wrist motion and grip strength during short-term follow-up. Therapeutic IV. Copyright

  7. EXTINCTION LAWS TOWARD STELLAR SOURCES WITHIN A DUSTY CIRCUMSTELLAR MEDIUM AND IMPLICATIONS FOR TYPE IA SUPERNOVAE

    International Nuclear Information System (INIS)

    Nagao, Takashi; Maeda, Keiichi; Nozawa, Takaya

    2016-01-01

    Many astronomical objects are surrounded by dusty environments. In such dusty objects, multiple scattering processes of photons by circumstellar (CS) dust grains can effectively alter extinction properties. In this paper, we systematically investigate the effects of multiple scattering on extinction laws for steady-emission sources surrounded by the dusty CS medium using a radiation transfer simulation based on the Monte Carlo technique. In particular, we focus on whether and how the extinction properties are affected by properties of CS dust grains by adopting various dust grain models. We confirm that behaviors of the (effective) extinction laws are highly dependent on the properties of CS grains, especially the total-to-selective extinction ratio R V , which characterizes the extinction law and can be either increased or decreased and compared with the case without multiple scattering. We find that the criterion for this behavior is given by a ratio of albedos in the B and V bands. We also find that either small silicate grains or polycyclic aromatic hydrocarbons are necessary for realizing a low value of R V as often measured toward SNe Ia if the multiple scattering by CS dust is responsible for their non-standard extinction laws. Using the derived relations between the properties of dust grains and the resulting effective extinction laws, we propose that the extinction laws toward dusty objects could be used to constrain the properties of dust grains in CS environments.

  8. EXTINCTION LAWS TOWARD STELLAR SOURCES WITHIN A DUSTY CIRCUMSTELLAR MEDIUM AND IMPLICATIONS FOR TYPE IA SUPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Nagao, Takashi; Maeda, Keiichi [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Nozawa, Takaya, E-mail: nagao@kusastro.kyoto-u.ac.jp [National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo 181-8588 (Japan)

    2016-06-01

    Many astronomical objects are surrounded by dusty environments. In such dusty objects, multiple scattering processes of photons by circumstellar (CS) dust grains can effectively alter extinction properties. In this paper, we systematically investigate the effects of multiple scattering on extinction laws for steady-emission sources surrounded by the dusty CS medium using a radiation transfer simulation based on the Monte Carlo technique. In particular, we focus on whether and how the extinction properties are affected by properties of CS dust grains by adopting various dust grain models. We confirm that behaviors of the (effective) extinction laws are highly dependent on the properties of CS grains, especially the total-to-selective extinction ratio R{sub V}, which characterizes the extinction law and can be either increased or decreased and compared with the case without multiple scattering. We find that the criterion for this behavior is given by a ratio of albedos in the B and V bands. We also find that either small silicate grains or polycyclic aromatic hydrocarbons are necessary for realizing a low value of R{sub V} as often measured toward SNe Ia if the multiple scattering by CS dust is responsible for their non-standard extinction laws. Using the derived relations between the properties of dust grains and the resulting effective extinction laws, we propose that the extinction laws toward dusty objects could be used to constrain the properties of dust grains in CS environments.

  9. Determination of Endograft Apposition, Position, and Expansion in the Aortic Neck Predicts Type Ia Endoleak and Migration After Endovascular Aneurysm Repair.

    Science.gov (United States)

    Schuurmann, Richte C L; van Noort, Kim; Overeem, Simon P; van Veen, Ruben; Ouriel, Kenneth; Jordan, William D; Muhs, Bart E; 't Mannetje, Yannick W; Reijnen, Michel M P J; Fioole, Bram; Ünlü, Çağdaş; Brummel, Peter; de Vries, Jean-Paul P M

    2018-03-01

    To describe the added value of determining changes in position and apposition on computed tomography angiography (CTA) after endovascular aneurysm repair (EVAR) to detect early caudal displacement of the device and to prevent type Ia endoleak. Four groups of elective EVAR patients were selected from a dataset purposely enriched with type Ia endoleak and migration (>10 mm) cases. The groups included cases of late type Ia endoleak (n=36), migration (n=9), a type II endoleak (n=16), and controls without post-EVAR complications (n=37). Apposition of the endograft fabric with the aortic neck, shortest distance between the fabric and the renal arteries, expansion of the main body (or dilatation of the aorta in the infrarenal sealing zone), and tilt of the endograft toward the aortic axis were determined on the first postoperative and the last available CTA scan without type Ia endoleak or migration. Differences in these endograft dimensions were compared between the first vs last scan and among the 4 groups. No significant differences in endograft configurations were observed among the groups on the first postoperative CTA scan. On the last CTA scan before a complication arose, the position of the fabric relative to the renal arteries, expansion of the main body, and apposition of the fabric with the aortic neck were significantly different between the type Ia endoleak (median follow-up 15 months) and migration groups (median follow-up 23 months) compared with the control group (median follow-up 19 months). Most endograft dimensions had changed significantly compared with the first postoperative CTA scan for all groups. Apposition had increased in the control group but had decreased significantly in the type Ia endoleak and migration groups. Progressive changes in dimensions of the endograft within the infrarenal neck could be detected on regular CTA scans before the complication became urgent in many patients.

  10. Tophaceous gout in a female premenopausal patient with an unexpected diagnosis of glycogen storage disease type Ia: a case report and literature review.

    Science.gov (United States)

    Zhang, Bingqing; Zeng, Xuejun

    2016-11-01

    A young female with recurrent tophaceous gout and infertility presented to our clinic. On clinical evaluation, hypoglycaemia, hypertriglyceridaemia, lactic acidosis, and hepatomegaly were noted. Targeted gene sequencing revealed a novel composite heterozygous c.190G>T/c.508C>T mutation in the G6PC gene of the patient, leading to a diagnosis of glycogen storage disease type Ia. Her father possessed a heterozygous c.190G>T mutation, and her mother possessed a heterozygous c.508C>T mutation. A search of the previous literature revealed 16 reported cases of glycogen storage disease type Ia with gout. Here, we describe a female patient with gout, review previous cases, and discuss the mechanisms of gout and hyperuricaemia in glycogen storage disease type Ia.

  11. Disease progression and search for monogenic diabetes among children with new onset type 1 diabetes negative for ICA, GAD- and IA-2 Antibodies

    DEFF Research Database (Denmark)

    Pörksen, Sven; Laborie, Lene Bjerke; Nielsen, Lotte

    2010-01-01

    BACKGROUND: To investigate disease progression the first 12 months after diagnosis in children with type 1 diabetes negative (AAB negative) for pancreatic autoantibodies [islet cell autoantibodies(ICA), glutamic acid decarboxylase antibodies (GADA) and insulinoma-associated antigen-2 antibodies (IA......-2A)]. Furthermore the study aimed at determining whether mutations in KCNJ11, ABCC8, HNF1A, HNF4A or INS are common in AAB negative diabetes. MATERIALS AND METHODS: In 261 newly diagnosed children with type 1 diabetes, we measured residual β-cell function, ICA, GADA, and IA-2A at 1, 6 and 12 months...... treatment after four weeks on 1.0-1.2 mg/kg/24 h glibenclamide. CONCLUSION: GAD, IA-2A, and ICA negative children with new onset type 1 diabetes have slower disease progression as assessed by residual beta-cell function and improved glycemic control 12 months after diagnosis. One out of 24 had a mutation...

  12. Disease progression and search for monogenic diabetes among children with new onset type 1 diabetes negative for ICA, GAD- and IA-2 Antibodies

    DEFF Research Database (Denmark)

    Pörksen, Sven; Laborie, Lene; Nielsen, Lotte

    2010-01-01

    BACKGROUND:To investigate disease progression the first 12 months after diagnosis in children with type 1 diabetes negative (AAB negative) for pancreatic autoantibodies [islet cell autoantibodies(ICA), glutamic acid decarboxylase antibodies (GADA) and insulinoma-associated antigen-2 antibodies (IA......-2A)]. Furthermore the study aimed at determining whether mutations in KCNJ11, ABCC8, HNF1A, HNF4A or INS are common in AAB negative diabetes.MATERIALS AND METHODS:In 261 newly diagnosed children with type 1 diabetes, we measured residual î-cell function, ICA, GADA, and IA-2A at 1, 6 and 12 months...... treatment after four weeks on 1.0-1.2 mg/kg/24 h glibenclamide.CONCLUSION:GAD, IA-2A, and ICA negative children with new onset type 1 diabetes have slower disease progression as assessed by residual beta-cell function and improved glycemic control 12 months after diagnosis. One out of 24 had a mutation...

  13. The Carnegie Supernova Project. I. Third Photometry Data Release of Low-redshift Type Ia Supernovae and Other White Dwarf Explosions

    DEFF Research Database (Denmark)

    Krisciunas, Kevin; Contreras, Carlos; Burns, Christopher R.

    2017-01-01

    We present final natural-system optical (ugriBV) and near-infrared (YJH) photometry of 134 supernovae (SNe) with probable white dwarf progenitors that were observed in 2004-2009 as part of the first stage of the Carnegie Supernova Project (CSP-I). The sample consists of 123 Type. Ia SNe, 5 Type...

  14. Two transitional type Ia supernovae located in the Fornax cluster member NGC 1404: SN 2007on and SN 2011iv

    Science.gov (United States)

    Gall, C.; Stritzinger, M. D.; Ashall, C.; Baron, E.; Burns, C. R.; Hoeflich, P.; Hsiao, E. Y.; Mazzali, P. A.; Phillips, M. M.; Filippenko, A. V.; Anderson, J. P.; Benetti, S.; Brown, P. J.; Campillay, A.; Challis, P.; Contreras, C.; Elias de la Rosa, N.; Folatelli, G.; Foley, R. J.; Fraser, M.; Holmbo, S.; Marion, G. H.; Morrell, N.; Pan, Y.-C.; Pignata, G.; Suntzeff, N. B.; Taddia, F.; Robledo, S. Torres; Valenti, S.

    2018-03-01

    We present an analysis of ultraviolet (UV) to near-infrared observations of the fast-declining Type Ia supernovae (SNe Ia) 2007on and 2011iv, hosted by the Fornax cluster member NGC 1404. The B-band light curves of SN 2007on and SN 2011iv are characterised by Δm15 (B) decline-rate values of 1.96 mag and 1.77 mag, respectively. Although they have similar decline rates, their peak B- and H-band magnitudes differ by 0.60 mag and 0.35 mag, respectively. After correcting for the luminosity vs. decline rate and the luminosity vs. colour relations, the peak B-band and H-band light curves provide distances that differ by 14% and 9%, respectively. These findings serve as a cautionary tale for the use of transitional SNe Ia located in early-type hosts in the quest to measure cosmological parameters. Interestingly, even though SN 2011iv is brighter and bluer at early times, by three weeks past maximum and extending over several months, its B - V colour is 0.12 mag redder than that of SN 2007on. To reconcile this unusual behaviour, we turn to guidance from a suite of spherical one-dimensional Chandrasekhar-mass delayed-detonation explosion models. In this context, 56Ni production depends on both the so-called transition density and the central density of the progenitor white dwarf. To first order, the transition density drives the luminosity-width relation, while the central density is an important second-order parameter. Within this context, the differences in the B - V colour evolution along the Lira regime suggest that the progenitor of SN 2011iv had a higher central density than SN 2007on. The photometry tables are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/611/A58

  15. Surface-bound capsular polysaccharide of type Ia group B Streptococcus mediates C1 binding and activation of the classic complement pathway

    International Nuclear Information System (INIS)

    Levy, N.J.; Kasper, D.L.

    1986-01-01

    The role of surface-bound type Ia group B Streptococcus (GBS) capsular polysaccharide in anti-body-independent binding of C1 and activation of the classic component pathway was investigated. In a radiolabeled bacterial-polymorphonuclear leukocyte (PMN) association assay, a measure of bacterial opsonization, preincubation of 3 H-type Ia GBS with purified F(ab') 2 to the organism blocked the association of the bacteria with PMN', and the inhibitory effect was dose dependent. The specificity of F(ab') 2 blocking was shown after adsorption of F(ab') 2 with type Ia polysaccharide-sensitized erythrocytes. Polysaccharide-adsorbed F(ab') 2 had a 70% decrease in ability to block the association of bacteria with PMN. Neuraminidase digestion removed 80% of the terminal sialic acid residues from the native polysaccharide. These neuraminidase-digested organisms had a 72% decrease in binding and transfer of purified C1 compared with non-enzyme-treated organisms. Type Ia capsular polysaccharide bound to sheep erythrocytes promoted classic complement pathway-mediated hemolysis of the cells. The role of C1 inhibitor (INH) in modulation of C1 activation by the organisms was investigated. The possibility existed that the C1 INH could be bound by the bacteria, allowing C1 activation to occur in the fluid phase. The inhibitor was purified from human serum, and its activity was measured before and after incubation with type Ia GBS. The organisms had no effect on C1 INH activity. Thus surface-bound capsular polysacchardie of type Ia GBS mediates C1 binding and classic pathway activation, and this does not involve the C1 INH

  16. Hereditary neuropathies: systematization and diagnostics (clinical case of hereditary motor and sensor neuropathy of the IA type

    Directory of Open Access Journals (Sweden)

    Kolokolova A.M.

    2016-09-01

    Full Text Available Aim: to study the value of routine methods (clinical symptoms, electrophysiological findings and results of DNA analysis in diagnostics of hereditary motor sensory neuropathy type IA in outpatient clinics. Material and Methods. The review of foreign literature is represented. The phenotypic polymorphism, genetic heterogeneity and the difficulties of diagnostics are identified. A family with hereditary motor sensory neuropathy of lAtype is presented, which was diagnosed on the base of available methods in outpatient practice (clinical symptoms, genealogical method, electro-physiological findings and DNA analysis results. Results. Routine algorithm (consistent valuation of clinical symptoms, neurophysiologic findings and the results of DNA analysis helped to verify the diagnosis of hereditary motor sensory neuropathy of lAtype in outpatient practice after more than 20 years of the onset of the disease. Conclusion. The neurologists of outpatient clinics and other specialists must be informed about the availability of diagnostics of hereditary diseases of nervous system.

  17. SHADOWS OF OUR FORMER COMPANIONS: HOW THE SINGLE-DEGENERATE BINARY TYPE IA SUPERNOVA SCENARIO AFFECTS REMNANTS

    Energy Technology Data Exchange (ETDEWEB)

    Gray, William J.; Raskin, Cody; Owen, J. Michael [Lawrence Livermore National Laboratory, P.O. Box 808, L-038, Livermore, CA 94550 (United States)

    2016-12-10

    Here we present three-dimensional high-resolution simulations of Type Ia supernova in the presence of a non-degenerate companion. We find that the presence of a nearby companion leaves a long-lived hole in the supernova ejecta. In particular, we aim to study the long-term evolution of this hole as the supernova ejecta interacts with the surrounding interstellar medium (ISM). Using estimates for the X-ray emission, we find that the hole generated by the companion remains for many centuries after the interaction between the ejecta and the ISM. We also show that the hole is discernible over a wide range of viewing angles and companion masses.

  18. STScI-PRC96-21b DISTANCE MEASUREMENTS TO A TYPE-IA SUPERNOVA BEARING GALAXY

    Science.gov (United States)

    2002-01-01

    This Hubble Space Telescope image shows NGC 4639, a spiral galaxy located 78 million light-years away in the Virgo cluster of galaxies. The blue dots in the galaxy's outlying regions indicate the presence of young stars. Among them are young, bright stars called Cepheids, which are used as reliable milepost markers to obtain accurate distances to nearby galaxies. Astronomers measure the brightness of Cepheids to calculate the distance to a galaxy. Allan Sandage's team used Cepheids to measure the distance to NGC 4639, the farthest galaxy to which Cepheid distance has been calculated. After using Cepheids to calculate the distance to NGC 4639, the team compared the results to the peak brightness measurements of SN 1990N, a type Ia supernova located in the galaxy. Then they compared those numbers with the peak brightness of supernovae similarly calibrated in nearby galaxies. The team then determined that type Ia supernovae are reliable secondary distance markers, and can be used to determine distances to galaxies several hundred times farther away than Cepheids. An accurate value for the Hubble Constant depends on Cepheids and secondary distance methods. The color image was made from separate exposures taken in the visible and near-infrared regions of the spectrum with the Wide Field Planetary Camera 2. Credit: A. Sandage (Carnegie Observatories), A. Saha (Space Telescope Science Institute), G.A. Tammann, and L. Labhardt (Astronomical Institute, University Basel), F.D. Macchetto and N. Panagia (Space Telescope Science Institute/ European Space Agency), and NASA Image files in GIF and JPEG format and captions may be accessed on Internet via anonymous ftp from oposite.stsci.edu in /pubinfo.

  19. Rate of WD-WD head-on collisions in isolated triples is too low to explain standard type Ia supernovae

    Science.gov (United States)

    Toonen, S.; Perets, H. B.; Hamers, A. S.

    2018-02-01

    Context.Type Ia supernovae (Ia-SNe) are thought to arise from the thermonuclear explosions of white dwarfs (WDs). The progenitors of such explosions are still highly debated; in particular the conditions leading to detonations in WDs are not well understood in most of the suggested progenitor models. Nevertheless, direct head-on collisions of two WDs were shown to give rise to detonations and produce Ia-SNe - like explosions, and were suggested as possible progenitors. Aims.The rates of such collisions in dense globular clusters are far below the observed rates of type Ia SNe, but it was suggested that quasi-secular evolution of hierarchical triples could produce a high rate of such collisions. With regular secular evolution, the expected Ia-SNe rate from isolated triples is orders of magnitude below the observed rate. Here we aim to test if the rate of WD collisions in triples can be significantly enhanced if quasi-secular evolution is taken into account. Methods.We used detailed triple stellar evolution populations synthesis models coupled with dynamical secular evolution to calculate the rates of WD-WD collisions in triples and their properties. We explored a range of models with different realistic initial conditions and derived the expected SNe total mass, mass-ratio and delay time distributions for each of the models. Results.We find that the SNe rate from WD-WD collisions is of the order of 0.1% of the observed Ia-SNe rate across all our models, and the delay-time distribution is almost uniform in time, and is inconsistent with observations. Conclusions.We conclude that SNe from WD-WD collisions in isolated triples can at most provide for a small fraction of Ia-SNe, and can not serve as the main progenitors of such explosions.

  20. Ocular findings in patients with oculocutaneous albinism type ia with G47D tyrosinase gene mutation in Puerto Rico: a case report.

    Science.gov (United States)

    Rodríguez-Agramonte, Ferdinand; Izquierdo, Natalio J; Cadilla, Carmen

    2013-01-01

    Previous studies have suggested that the G47D mutation leads patients to develop Oculocutaneous albinism (OCA) type IA. This mutation has been described in the Canary Islands. Historically, there has been a migration from the Canary Islands to some regions of Puerto Rico. To report on the ocular findings of two Puerto Rican patients with OCA IA due to the G47D Tyrosinase gene mutation. PATIENT AND FINDINGS: Two unrelated patients with OCA underwent a comprehensive eye examination and were referred for genetic analysis. Patients had almost total iris transillumination, clear lenses, foveal hypoplasia with transparent maculae, and albinotic mid peripheries. Both patients had nystagmus, and only one patient had strabismus. Patients with the G47D muta- tion leading to OCA IA have poor visual acuities and poorly pigmented phenotypic ophthalmic findings. Further studies comparing ocular findings in patients th several mutations leading to OCA IA are warranted. To our knowledge this is the first report on ocular findings in Puerto Rican patients with OCA type IA with the rare G47D mutation.

  1. No Contribution of GAD-65 and IA-2 Autoantibodies around Time of Diagnosis to the Increasing Incidence of Juvenile Type 1 Diabetes: A 9-Year Nationwide Danish Study

    Directory of Open Access Journals (Sweden)

    Steffen U. Thorsen

    2016-01-01

    Full Text Available Aims. A new perspective on autoantibodies as pivotal players in the pathogenesis of type 1 diabetes (T1D has recently emerged. Our key objective was to examine whether increased levels of autoantibodies against the β-cell autoantigens glutamic acid decarboxylase (isoform 65 (GADA and insulinoma associated antigen-2A (IA-2A mirrored the 3.4% annual increase in incidence of T1D. Methods. From the Danish Childhood Diabetes Register, we randomly selected 500 patients and 500 siblings for GADA and IA-2A analysis (1997 through 2005. Blood samples were taken within three months after onset. A robust log-normal regression model was used. Nine hundred children and adolescents had complete records and were included in the analysis. Cochran-Armitage test for trend was used to evaluate changes in prevalence of autoantibody positivity by period. Results. No significant changes in levels of GADA and IA-2A were found over our 9-year study period. No trends in autoantibody positivity—in either patients or siblings—were found. Levels of GADA and IA-2A were significantly associated with HLA risk groups and GADA with age. Conclusion. The prevalence of positivity and the levels of GADA and IA-2A have not changed between 1997 and 2005 in newly diagnosed patients with T1D and their siblings without T1D.

  2. Confirmation with the SALT telescope of a young Type Ia supernova at z=0.046 discovered during the "Deeper Wider Faster" program

    Science.gov (United States)

    Andreoni, I.; Cooke, J.; Pritchard, T. A.; Kotze, M.; Miszalski, B.; Shara, M.; Mestric, U.; Tucker, B.; Plant, K.; Spiewak, R.; Ryder, S.; Abbott, T.; Allen, Rebecca; Anderson, G.; Asher, A.; Baglio, M. C.; Bannister, K.; Bell, M.; Bernard, S.; Bhandari, S.; Caleb, M.; Campana, S.; Coward, D.; Curtin, C.; D'Avanzo, P.; Deller, A.; Devlin, J. F.; Farah, W.; Fluke, C.; Flynn, C.; Foran, G.; Fugazza, D.; Gawin, B.; Hegarty, S.; Hodgson, R.; Hodgson, S.; Horst, J.; Howell, E.; Hussaini, I.; Jacobs, C.; Ko, M.; Lien, A.; Meade, B.; Melandri, A.; Moller, A.; Murphy, M. T.; Nanayakkara, T.; O'Neill, M.; Oslowski, S.; Peng, B.; Petroff, E.; Rest, A.; Robert, F.; Valdes, F.; Vohl, D.

    2017-02-01

    Further to ATel #10072, we report an additional discovery of a young Type Ia supernova from imaging on February 03.5, 2017 UT with the Dark Energy Camera (DECam) at CTIO during the recent & ldquo;Deeper, Wider, Faster & rdquo; program observations.

  3. Gravitational lensing statistics with extragalactic surveys III. Joint constraints on lambda(0) and Omega(0) from lensing statistics and the m-z relation for type Ia supernovae

    NARCIS (Netherlands)

    Helbig, P

    1999-01-01

    I present constraints on cosmological parameters in the lambda(0)-Omega(0) plane from a joint analysis of gravitational lensing statistics (Helbig et al. 1999b) and the magnitude-redshift relation for Type Ia supernovae (Perlmutter et al. 1999; Riess et al. 1998). I discuss reasons why this

  4. Hepatocytes Contribute to Residual Glucose Production in a Mouse Model for Glycogen Storage Disease Type Ia

    NARCIS (Netherlands)

    Hijmans, Brenda S.; Boss, Andreas; van Dijk, Theo H.; Soty, Maud; Wolters, Henk; Mutel, Elodie; Groen, Albert K.; Derks, Terry G. J.; Mithieux, Gilles; Heerschap, Arend; Reijngoud, Dirk-Jan; Rajas, Fabienne; Oosterveer, Maaike H.

    2017-01-01

    It is a long-standing enigma how glycogen storage disease (GSD) type I patients retain a limited capacity for endogenous glucose production despite the loss of glucose-6-phosphatase activity. Insight into the source of residual endogenous glucose production is of clinical importance given the risk

  5. Offline analysis in SNLS: measurement of type-Ia supernovae explosion rate and cosmological parameters

    International Nuclear Information System (INIS)

    Lusset, Vincent

    2006-01-01

    The Supernova Legacy Survey is a second generation experiment for the measurement of cosmological parameters using type-la supernovae. Il follows the discovery of the acceleration of the expansion of the Universe, attributed to an unknown 'dark energy'. This thesis presents a type-la supernovae search using an offline analysis of SNLS data. It makes it possible to detect the supernovae that were missed online and to study possible selection biases. One of its principal characteristics is that it uses entirely automatic selection criteria. This type of automated offline analysis had never been carried out before for data reaching this redshift. This analysis enabled us to discover 73 additional SNIa candidates compared to those identified in the real time analysis on the same data, representing an increase of more than 50% of the number of supernovae. The final Hubble diagram contains 262 SNIa which gives us, for a flat ACDM model, the following values for the cosmological parameters: Ω M = 0,31 ± 0,028 (stat) ± 0,036 (syst) et Ω A = 0,69. This offline analysis of SNLS data opens new horizons, both by checking for possible biases in current measurements of cosmological parameters by supernovae experiments and by preparing the third generation experiments, on the ground or in space, which will detect thousands of SNIa. (author) [fr

  6. Adediran, IA

    African Journals Online (AJOL)

    Adediran, IA. Vol 14, No 1 (2005) - Articles Haematological parameters in prospective Nigerian blood donors rejected on account of anaemia and/or microfilaria infestation. Abstract. ISSN: 1115-2613. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL ...

  7. Esin, IA

    African Journals Online (AJOL)

    Esin, IA. Vol 13, No 2 (2010) - Articles hereditary multiple exastoses: Case report. Abstract PDF · Vol 14, No 4 (2011) - Articles Knowledge of human immunodeficiency virus post-exposure prophylaxis among doctors in a Nigerian tertiary hospital. Abstract PDF. ISSN: 1119-3077. AJOL African Journals Online. HOW TO USE ...

  8. Edwin, IA

    African Journals Online (AJOL)

    Edwin, IA. Vol 2, No 1 (2004) - Articles Solar energy resource assessment for Ghana Abstract · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's Partners · Terms and Conditions of Use · Contact AJOL · News. OTHER RESOURCES.

  9. Durosaro, IA

    African Journals Online (AJOL)

    Durosaro, IA. Vol 2, No 2 (2009) - Articles Guidance and Behaviour Management in early Childhood: Need for Reform in Child Care Development Education Abstract PDF. ISSN: 2006-7593. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's ...

  10. Adimula, IA

    African Journals Online (AJOL)

    Adimula, IA. Vol 17, No 1 (2005) - Articles Effects of rain on microwave and satellite communications in equatorial and tropical regions. Abstract · Vol 20, No 2 (2008) - Articles Temperature and precipitation relation in the Sub-Sahel Abstract · Vol 20, No 2 (2008) - Articles Analysis of radiosonde data on tropospheric water ...

  11. Imoudu, IA

    African Journals Online (AJOL)

    Imoudu, IA. Vol 2, No 1 (2015) - Articles Correlates of childhood enuresis in north western Nigeria Abstract. ISSN: 2354-4325. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's Partners · Terms and Conditions of Use · Contact AJOL · News.

  12. Type Ia Supernova Properties as a Function of the Distance to the Host Galaxy in the SDSS-II SN Survey

    Energy Technology Data Exchange (ETDEWEB)

    Galbany, Lluis [Institut de Fisica d' Altes Energies (IFAE), Barcelona (Spain); et al.

    2012-08-20

    We use type-Ia supernovae (SNe Ia) discovered by the SDSS-II SN Survey to search for dependencies between SN Ia properties and the projected distance to the host galaxy center, using the distance as a proxy for local galaxy properties (local star-formation rate, local metallicity, etc.). The sample consists of almost 200 spectroscopically or photometrically confirmed SNe Ia at redshifts below 0.25. The sample is split into two groups depending on the morphology of the host galaxy. We fit light-curves using both MLCS2k2 and SALT2, and determine color (AV, c) and light-curve shape (delta, x1) parameters for each SN Ia, as well as its residual in the Hubble diagram. We then correlate these parameters with both the physical and the normalized distances to the center of the host galaxy and look for trends in the mean values and scatters of these parameters with increasing distance. The most significant (at the 4-sigma level) finding is that the average fitted AV from MLCS2k2 and c from SALT2 decrease with the projected distance for SNe Ia in spiral galaxies. We also find indications that SNe in elliptical galaxies tend to have narrower light-curves if they explode at larger distances, although this may be due to selection effects in our sample. We do not find strong correlations between the residuals of the distance moduli with respect to the Hubble flow and the galactocentric distances, which indicates a limited correlation between SN magnitudes after standardization and local host metallicity.

  13. Glycogen Storage Disease Type Ia: Linkage of Glucose, Glycogen, Lactic Acid, Triglyceride, and Uric Acid Metabolism

    Science.gov (United States)

    Sever, Sakine; Weinstein, David A.; Wolfsdorf, Joseph I.; Gedik, Reyhan; Schaefer, Ernst J.

    2013-01-01

    Case Summary A female presented in infancy with hypotonia, undetectable serum glucose, lactic acidosis, and triglycerides > 5,000 mg/dl. The diagnosis of type 1A glycogen storage disease (GSD) was made by liver biopsy that showed increased glycogen and absent glucose-6-phosphatase enzyme activity. She was treated with dextrose feeding, which was replaced by frequent cornstarch feeding, with improvement of her metabolic parameters. At age 18 years she had marked hypertriglyceridemia (3,860 mg/dl) and eruptive xanthomas, and was treated with fenofibrate, atorvastatin, and fish oil. At age 29 years she was noted to have multiple liver adenomas, severe anemia, and hyperuricemia. Aggressive cornstarch therapy was commenced with a goal of maintaining her blood glucose levels > 75 mg/dl and lactate levels 75 mg/dl is critical in the management of this disease. PMID:23312056

  14. A CHANDRASEKHAR MASS PROGENITOR FOR THE TYPE Ia SUPERNOVA REMNANT 3C 397 FROM THE ENHANCED ABUNDANCES OF NICKEL AND MANGANESE

    International Nuclear Information System (INIS)

    Yamaguchi, Hiroya; Williams, Brian J.; Petre, Robert; Badenes, Carles; Foster, Adam R.; Brickhouse, Nancy S.; Bravo, Eduardo; Maeda, Keiichi; Nobukawa, Masayoshi; Koyama, Katsuji; Eriksen, Kristoffer A.

    2015-01-01

    Despite decades of intense efforts, many fundamental aspects of Type Ia supernovae (SNe Ia) remain elusive. One of the major open questions is whether the mass of an exploding white dwarf (WD) is close to the Chandrasekhar limit. Here, we report the detection of strong K-shell emission from stable Fe-peak elements in the Suzaku X-ray spectrum of the Type Ia supernova remnant (SNR) 3C 397. The high Ni/Fe and Mn/Fe mass ratios (0.11–0.24 and 0.018–0.033, respectively) in the hot plasma component that dominates the K-shell emission lines indicate a degree of neutronization in the supernova ejecta that can only be achieved by electron capture in the dense cores of exploding WDs with a near-Chandrasekhar mass. This suggests a single-degenerate origin for 3C 397, since Chandrasekhar mass progenitors are expected naturally if the WD accretes mass slowly from a companion. Together with other results supporting the double-degenerate scenario, our work adds to the mounting evidence that both progenitor channels make a significant contribution to the SN Ia rate in star-forming galaxies

  15. A CHANDRASEKHAR MASS PROGENITOR FOR THE TYPE Ia SUPERNOVA REMNANT 3C 397 FROM THE ENHANCED ABUNDANCES OF NICKEL AND MANGANESE

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Hiroya; Williams, Brian J.; Petre, Robert [NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States); Badenes, Carles [Department of Physics and Astronomy and Pittsburgh Particle Physics, Astrophysics and Cosmology Center (PITT PACC), University of Pittsburgh, 3941 O’Hara Street, Pittsburgh, PA 15260 (United States); Foster, Adam R.; Brickhouse, Nancy S. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Bravo, Eduardo [E.T.S. Arquitectura del Vallès, Universitat Politècnica de Catalunya, Carrer Pere Serra 1-15, E-08173 Sant Cugat del Vallès (Spain); Maeda, Keiichi [Department of Astronomy, Kyoto University, Kitashirakawa-oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Nobukawa, Masayoshi; Koyama, Katsuji [Department of Physics, Kyoto University, Kitashirakawa-oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Eriksen, Kristoffer A., E-mail: hiroya.yamaguchi@nasa.gov [Theoretical Design Division, Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States)

    2015-03-10

    Despite decades of intense efforts, many fundamental aspects of Type Ia supernovae (SNe Ia) remain elusive. One of the major open questions is whether the mass of an exploding white dwarf (WD) is close to the Chandrasekhar limit. Here, we report the detection of strong K-shell emission from stable Fe-peak elements in the Suzaku X-ray spectrum of the Type Ia supernova remnant (SNR) 3C 397. The high Ni/Fe and Mn/Fe mass ratios (0.11–0.24 and 0.018–0.033, respectively) in the hot plasma component that dominates the K-shell emission lines indicate a degree of neutronization in the supernova ejecta that can only be achieved by electron capture in the dense cores of exploding WDs with a near-Chandrasekhar mass. This suggests a single-degenerate origin for 3C 397, since Chandrasekhar mass progenitors are expected naturally if the WD accretes mass slowly from a companion. Together with other results supporting the double-degenerate scenario, our work adds to the mounting evidence that both progenitor channels make a significant contribution to the SN Ia rate in star-forming galaxies.

  16. Prespacer processing and specific integration in a Type I-A CRISPR system

    Science.gov (United States)

    Rollie, Clare; Graham, Shirley; Rouillon, Christophe

    2018-01-01

    Abstract The CRISPR–Cas system for prokaryotic adaptive immunity provides RNA-mediated protection from viruses and mobile genetic elements. Adaptation is dependent on the Cas1 and Cas2 proteins along with varying accessory proteins. Here we analyse the process in Sulfolobus solfataricus, showing that while Cas1 and Cas2 catalyze spacer integration in vitro, host factors are required for specificity. Specific integration also requires at least 400 bp of the leader sequence, and is dependent on the presence of hydrolysable ATP, suggestive of an active process that may involve DNA remodelling. Specific spacer integration is associated with processing of prespacer 3′ ends in a PAM-dependent manner. This is reflected in PAM-dependent processing of prespacer 3′ ends in vitro in the presence of cell lysate or the Cas4 nuclease, in a reaction consistent with PAM-directed binding and protection of prespacer DNA. These results highlight the diverse interplay between CRISPR–Cas elements and host proteins across CRISPR types. PMID:29228332

  17. Glycogen storage disease type Ia: linkage of glucose, glycogen, lactic acid, triglyceride, and uric acid metabolism.

    Science.gov (United States)

    Sever, Sakine; Weinstein, David A; Wolfsdorf, Joseph I; Gedik, Reyhan; Schaefer, Ernst J

    2012-01-01

    A female presented in infancy with hypotonia, undetectable serum glucose, lactic acidosis, and triglycerides >5000 mg/dL. The diagnosis of type 1A glycogen storage disease was made via the result of a liver biopsy, which showed increased glycogen and absent glucose-6-phosphatase enzyme activity. The patient was treated with dextrose administered orally, which was replaced by frequent feedings of cornstarch, which resulted in an improvement of her metabolic parameters. At age 18 years of age, she had marked hypertriglyceridemia (3860 mg/dL) and eruptive xanthomas and was treated with fenofibrate, atorvastatin, and fish oil. At age 29 years she was noted to have multiple liver adenomas, severe anemia, and hyperuricemia. Aggressive cornstarch therapy was commenced with a goal of maintaining her blood glucose levels >75 mg/dL and lactate levels triglycerides 179, high-density lipoprotein cholesterol 32, and calculated low-density lipoprotein cholesterol 154. Her weight was stable with a body mass index of 24.8 kg/m(2). Her liver adenomas had decreased in size, and her anemia and hyperuricemia had improved. She was homozygous for the R83C missense mutation in G6PC. Our data indicate that optimized metabolic control to maintain blood glucose levels >75 mg/dL is critical in the management of this disease. Copyright © 2012. Published by Elsevier Inc.

  18. Multi-color light curves of type Ia supernovae on the color-magnitude diagram: A novel step toward more precise distance and extinction estimates

    International Nuclear Information System (INIS)

    Wang, Lifan; Goldhaber, Gerson; Aldering, Greg; Perlmutter, Saul

    2003-01-01

    We show empirically that fits to the color-magnitude relation of Type Ia supernovae after optical maximum can provide accurate relative extragalactic distances. We report the discovery of an empirical color relation for Type Ia light curves: During much of the first month past maximum, the magnitudes of Type Ia supernovae defined at a given value of color index have a very small magnitude dispersion; moreover, during this period the relation between B magnitude and B-V color (or B-Ror B-I color) is strikingly linear, to the accuracy of existing well-measured data. These linear relations can provide robust distance estimates, in particular, by using the magnitudes when the supernova reaches a given color. After correction for light curve stretch factor or decline rate, the dispersion of the magnitudes taken at the intercept of the linear color-magnitude relation are found to be around 0 m .08 for the sub-sample of supernovae with (B max - V max ) (le) 0 m 0.5, and around 0 m .11 for the sub-sample with (B max - V max ) (le) 0 m .2. This small dispersion is consistent with being mostly due to observational errors. The method presented here and the conventional light curve fitting methods can be combined to further improve statistical dispersions of distance estimates. It can be combined with the magnitude at maximum to deduce dust extinction. The slopes of the color-magnitude relation may also be used to identify intrinsically different SN Ia systems. The method provides a tool that is fundamental to using SN Ia to estimate cosmological parameters such as the Hubble constant and the mass and dark energy content of the universe

  19. Multi-color light curves of type Ia supernovae on thecolor-magnitude diagram: A novel step toward more precise distance andextinction estimates

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lifan; Goldhaber, Gerson; Aldering, Greg; Perlmutter, Saul

    2003-01-31

    We show empirically that fits to the color-magnituderelation of Type Ia supernovae after optical maximum can provide accuraterelative extragalactic distances. We report the discovery of an empiricalcolor relation for Type Ia light curves: During much of the first monthpast maximum, the magnitudes of Type Ia supernovae defined at a givenvalue of color index have a very small magnitude dispersion; moreover,during this period the relation between B magnitude and B-V color (or B-Ror B-I color) is strikingly linear, to the accuracy of existingwell-measured data. These linear relations can provide robust distanceestimates, in particular, by using the magnitudes when the supernovareaches a given color. After correction for light curve stretch factor ordecline rate, the dispersion of the magnitudes taken at the intercept ofthe linear color-magnitude relation are found to be around 0^m .08 forthe sub-sample of supernovae with (B_max - V_max) ?= 0^m 0.5, andaround 0^m.11 for the sub-sample with (B_max - V_max) ?= 0^m .2.This small dispersion is consistent with being mostly due toobservational errors. The method presented here and the conventionallight curve fitting methods can be combined to further improvestatistical dispersions of distance estimates. It can be combined withthe magnitude at maximum to deduce dust extinction. Theslopes of thecolor-magnitude relation may also be used to identify intrinsicallydifferent SN Ia systems. The method provides a tool that is fundamentalto using SN Ia to estimate cosmological parameters such as the Hubbleconstant and the mass and dark energy content of theuniverse.

  20. Zinc transporter-8 autoantibodies can replace IA-2 autoantibodies as a serological marker for juvenile onset type 1 diabetes in India

    Directory of Open Access Journals (Sweden)

    C Shivaprasad

    2014-01-01

    Full Text Available Introduction: Zinc transporter-8 (ZnT8 is an islet cell secretory granule membrane protein recently identified as an autoantigen in type 1 diabetes (T1D. The aim of this study was to estimate the prevalence of antibodies to ZnT8 (ZnT8A in juvenile onset T1D and to determine the utility of ZnT8A as an independent marker of autoimmunity either alone in antibody-negative subjects or in conjunction with glutamic acid decarboxylase (GAD and insulinoma-2 antigen antibodies (GADA and IA2A. Research Design: ZnT8A, GADA, and IA2A were measured in sera of consecutive T1D patients (n = 88, age range 2-18 years within 4 years of diagnosis and 88 sex-matched controls. Results: The prevalences of GADA, ZnT8a, and IA2A were 64.7%, 31.8% and 19.3%, respectively. In newly diagnosed patients, the frequency of ZnT8A was 45%. ZnT8A were positive in 26% of patients negative for both GADA and IA2A. IA2A were positive only in two patients who were negative for other two antibodies. Combined use of ZnT8A and GADA could detect 97% of antibody positive patients. In receiver operating characteristic (ROC analysis, the performances of GADA and ZnT8As were better than that of IA2A; and AUCs of GADA, ZnT8A, and IA2A for the prediction of T1D were 0.8, 0.65, and 0.59, respectively. Conclusions: ZnT8A complements GADA and increases the diagnostic sensitivity for detection of autoimmunity in juvenile-onset T1D. Inclusion of ZnT8A increases the proportion of patients with antibody positivity to nearly 80%. ZnT8A can replace IA2A as a serological marker for autoimmunity in Indian T1D patients without loss of sensitivity and specificity.

  1. Use of modified cornstarch therapy to extend fasting in glycogen storage disease types Ia and Ib1,2,3

    Science.gov (United States)

    Correia, Catherine E; Bhattacharya, Kaustuv; Lee, Philip J; Shuster, Jonathan J; Theriaque, Douglas W; Shankar, Meena N; Smit, G Peter A; Weinstein, David A

    2013-01-01

    Background Type I glycogen storage disease (GSD) is caused by a deficiency of glucose-6-phosphatase resulting in severe fasting hypoglycemia. Objective We compared the efficacy of a new modified starch with the currently used cornstarch therapy in patients with type Ia and Ib GSD. Design This was a randomized, 2-d, double-blinded, crossover pilot study comparing the commonly used uncooked cornstarch with the experimental starch in 12 subjects (6 GSDIa, 6 GSDIb) aged ≥13 y. At 2200, the subjects were given 100 g of digestible starch, and glucose and lactate were measured hourly until the subject's plasma glucose concentration reached 60 mg/dL or until the subject had fasted for 10 h. The order in which the products were tested was randomized in a blinded fashion. Results The matched-pair Gehan rank test for censored survival was used to compare the therapies. The experimental starch maintained blood glucose concentrations significantly longer than did the traditional therapy (P = 0.013) in the 2-sided analysis. Most of the benefit was found to be after glucose concentrations fell below 70 mg/dL. The currently used cornstarch resulted in higher peak glucose concentrations and a more rapid rate of fall than did the new starch. Conclusions The experimental starch was superior to standard therapy in preventing hypoglycemia (≤60 mg/dL). This therapy may allow patients with GSD to sleep through the night without awakening for therapy while enhancing safety. Additional studies are warranted to determine whether alternative dosing will further improve control in the therapeutic blood glucose range. PMID:18996862

  2. Early Observations of the Type Ia Supernova iPTF 16abc: A Case of Interaction with Nearby, Unbound Material and/or Strong Ejecta Mixing

    Science.gov (United States)

    Miller, A. A.; Cao, Y.; Piro, A. L.; Blagorodnova, N.; Bue, B. D.; Cenko, S. B.; Dhawan, S.; Ferretti, R.; Fox, O. D.; Fremling, C.; Goobar, A.; Howell, D. A.; Hosseinzadeh, G.; Kasliwal, M. M.; Laher, R. R.; Lunnan, R.; Masci, F. J.; McCully, C.; Nugent, P. E.; Sollerman, J.; Taddia, F.; Kulkarni, S. R.

    2018-01-01

    Early observations of Type Ia supernovae (SNe Ia) provide a unique probe of their progenitor systems and explosion physics. Here we report the intermediate Palomar Transient Factory (iPTF) discovery of an extraordinarily young SN Ia, iPTF 16abc. By fitting a power law to our early light curve, we infer that first light for the SN, that is, when the SN could have first been detected by our survey, occurred only 0.15{+/- }0.070.15 days before our first detection. In the ∼24 hr after discovery, iPTF 16abc rose by ∼2 mag, featuring a near-linear rise in flux for ≳ 3 days. Early spectra show strong C II absorption, which disappears after ∼7 days. Unlike the extensively observed Type Ia SN 2011fe, the {(B-V)}0 colors of iPTF 16abc are blue and nearly constant in the days after explosion. We show that our early observations of iPTF 16abc cannot be explained by either SN shock breakout and the associated, subsequent cooling or the SN ejecta colliding with a stellar companion. Instead, we argue that the early characteristics of iPTF 16abc, including (i) the rapid, near-linear rise, (ii) the nonevolving blue colors, and (iii) the strong C II absorption, are the result of either ejecta interaction with nearby, unbound material or vigorous mixing of radioactive 56Ni in the SN ejecta, or a combination of the two. In the next few years, dozens of very young normal SNe Ia will be discovered, and observations similar to those presented here will constrain the white dwarf explosion mechanism.

  3. 3'-UTR SNP rs2229611 in G6PC1 affects mRNA stability, expression and Glycogen Storage Disease type-Ia risk.

    Science.gov (United States)

    Karthi, Sellamuthu; Rajeshwari, Mohan; Francis, Amirtharaj; Saravanan, Matheshwaran; Varalakshmi, Perumal; Houlden, Henry; Thangaraj, Kumarasamy; Ashokkumar, Balasubramaniem

    2017-08-01

    The frequency of rs2229611, previously reported in Chinese, Caucasians, Japanese and Hispanics, was investigated for the first time in Indian ethnicity. We analyzed its role in the progression of Glycogen Storage Disease type-Ia (GSD-Ia) and breast cancer. Genotype data on rs2229611 revealed that the risk of GSD-Ia was higher (P=0.0195) with CC compared to TT/TC genotypes, whereas no such correlation was observed with breast cancer cases. We observed a strong linkage disequilibrium (LD) among rs2229611 and other disease causing G6PC1 variants (|D'|=1, r 2 =1). Functional validation performed in HepG2 cells using luciferase constructs showed significant (P<0.05) decrease in expression than wild-type 3'-UTR due to curtailed mRNA stability. Furthermore, AU-rich elements (AREs) mediated regulation of G6PC1 expression characterized using 3'-UTR deletion constructs showed a prominent decrease in mRNA stability. We then examined whether miRNAs are involved in controlling G6PC1 expression using pmirGLO-UTR constructs, with evidence of more distinct inhibition in the reporter function with rs2229611. These data suggests that rs2229611 is a crucial regulatory SNP which in homozygous state leads to a more aggressive disease phenotype in GSD-Ia patients. The implication of this result is significant in predicting disease onset, progression and response to disease modifying treatments in patients with GSD-Ia. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. IAS talk

    Indian Academy of Sciences (India)

    Srianand, IUCAA, Pune

    2009-07-31

    Jul 31, 2009 ... 60. 40. 20. 0. -20. -40. -60. Figure 2: VLBA 20cm images of some of the sources observed as part of the project:VLBA/08C-. 101. The typical rms is 0.15 mJy and the flux density ranges from 30 mJy to 700 mJy. Redshift evolution of 21cm absorbers: – Typeset by FoilTEX –. IAS, Bangalore ,Nov, 2009. 19 ...

  5. In Vivo Zinc Finger Nuclease-mediated Targeted Integration of a Glucose-6-phosphatase Transgene Promotes Survival in Mice With Glycogen Storage Disease Type IA.

    Science.gov (United States)

    Landau, Dustin J; Brooks, Elizabeth Drake; Perez-Pinera, Pablo; Amarasekara, Hiruni; Mefferd, Adam; Li, Songtao; Bird, Andrew; Gersbach, Charles A; Koeberl, Dwight D

    2016-04-01

    Glycogen storage disease type Ia (GSD Ia) is caused by glucose-6-phosphatase (G6Pase) deficiency in association with severe, life-threatening hypoglycemia that necessitates lifelong dietary therapy. Here we show that use of a zinc-finger nuclease (ZFN) targeted to the ROSA26 safe harbor locus and a ROSA26-targeting vector containing a G6PC donor transgene, both delivered with adeno-associated virus (AAV) vectors, markedly improved survival of G6Pase knockout (G6Pase-KO) mice compared with mice receiving the donor vector alone (P < 0.04). Furthermore, transgene integration has been confirmed by sequencing in the majority of the mice treated with both vectors. Targeted alleles were 4.6-fold more common in livers of mice with GSD Ia, as compared with normal littermates, at 8 months following vector administration (P < 0.02). This suggests a selective advantage for vector-transduced hepatocytes following ZFN-mediated integration of the G6Pase vector. A short-term experiment also showed that 3-month-old mice receiving the ZFN had significantly-improved biochemical correction, in comparison with mice that received the donor vector alone. These data suggest that the use of ZFNs to drive integration of G6Pase at a safe harbor locus might improve vector persistence and efficacy, and lower mortality in GSD Ia.

  6. Constraining the Single-degenerate Channel of Type Ia Supernovae with Stable Iron-group Elements in SNR 3C 397

    Energy Technology Data Exchange (ETDEWEB)

    Dave, Pranav; Kashyap, Rahul; Fisher, Robert [Department of Physics, University of Massachusetts Dartmouth, 285 Old Westport Road, North Dartmouth, MA 02740 (United States); Timmes, Frank [School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287 (United States); Townsley, Dean [Department of Physics and Astronomy, Box 870324, University of Alabama, Tuscaloosa, AL 35487 (United States); Byrohl, Chris [Institut für Astrophysik, Georg August Universität Göttingen, Friedrich-Hund-Platz 1, D-37077 Göttingen (Germany)

    2017-05-20

    Recent Suzaku X-ray spectra of supernova remnant (SNR) 3C 397 indicate enhanced stable iron group element abundances of Ni, Mn, Cr, and Fe. Seeking to address key questions about the progenitor and explosion mechanism of 3C 397, we compute nucleosynthetic yields from a suite of multidimensional hydrodynamics models in the near-Chandrasekhar-mass, single-degenerate paradigm for Type Ia supernovae (SNe Ia). Varying the progenitor white dwarf (WD) internal structure, composition, ignition, and explosion mechanism, we find that the best match to the observed iron peak elements of 3C 397 are dense (central density ≥6 × 10{sup 9} g cm{sup −3}), low-carbon WDs that undergo a weak, centrally ignited deflagration, followed by a subsequent detonation. The amount of {sup 56}Ni produced is consistent with a normal or bright normal SNe Ia. A pure deflagration of a centrally ignited, low central density (≃2 × 10{sup 9} g cm{sup −3}) progenitor WD, frequently considered in the literature, is also found to produce good agreement with 3C 397 nucleosynthetic yields, but leads to a subluminous SN Ia event, in conflict with X-ray line width data. Additionally, in contrast to prior work that suggested a large supersolar metallicity for the WD progenitor for SNR 3C 397, we find satisfactory agreement for solar- and subsolar-metallicity progenitors. We discuss a range of implications our results have for the single-degenerate channel.

  7. Genetic polymorphisms in bone morphogenetic protein receptor type IA gene predisposes individuals to ossification of the posterior longitudinal ligament of the cervical spine via the smad signaling pathway.

    Science.gov (United States)

    Wang, Hao; Jin, Weitao; Li, Haibin

    2018-02-20

    The present study investigated the molecular mechanisms underlying the 4A > C and -349C > T single nucleotide polymorphisms (SNPs) in bone morphogenetic protein receptor type IA (BMPR-IA) gene, which significantly associated with the occurrence and the extent of ossification of the posterior longitudinal ligament (OPLL) in the cervical spine. The SNPs in BMPR-IA gene were genotyped, and the association with the occurrence and severity of OPLL were evaluated in 356 OPLL patients and 617 non-OPLL controls. In stably transfected mouse embryonic mesenchymal stem cells (C3H10T1/2), the expression levels of the BMPR-IA gene and Smad4 protein as well as phosphorylated Smad1/5/8 were detected by Western blotting. In addition, the alkaline phosphatase (ALP) and osteocalcin (OC) activity of osteogenesis specificity protein was assessed using the ALP quantitation and osteocalcin radioimmunoassay kit, respectively. The 4A > C and the -349C > T polymorphisms of BMPR-IA gene were significantly associated with the development of OPLL in the cervical spine. The C allele type in 4A > C polymorphism significantly increases the occurrence and the extent of OPLL. The T allele type in -349C > T polymorphism significantly increases the susceptibility to OPLL, but not the extent of OPLL. The current results further validate our previous observations. The expression levels of BMPR-IA gene were significantly increased in pcDNA3.1/BMPR-IA (mutation type, MT -349C > T; MT 4A > C; MT -349C > T and 4A > C) vector-transfected C3H10T1/2 cells compared to the wild type (WT) vector-transfected cells. The levels of phosphorylated Smad1/5/8 and ALP activity were significantly increased in pcDNA3.1/BMPR-IA (MT -349C > T) vector-transfected C3H10T1/2 cells compared to the WT vector-transfected cells. However, no significant differences were observed in the protein levels of phosphorylated Smad1/5/8 and the ALP activity between MT A/C and WT vector

  8. On the source of the dust extinction in type Ia supernovae and the discovery of anomalously strong Na I absorption

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, M. M.; Morrell, Nidia; Hsiao, E. Y.; Campillay, Abdo; Contreras, Carlos [Carnegie Observatories, Las Campanas Observatory, Casilla 601, La Serena (Chile); Simon, Joshua D.; Burns, Christopher R.; Persson, Sven E.; Thompson, I. B.; Freedman, Wendy L. [Observatories of the Carnegie Institution for Science, 813 Santa Barbara St., Pasadena, CA 91101 (United States); Cox, Nick L. J. [Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D bus 2401, 3001 Leuven (Belgium); Foley, Ryan J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Karakas, Amanda I. [Research School of Astronomy and Astrophysics, The Australian National University, Weston, ACT 2611 (Australia); Patat, F. [European Southern Observatory (ESO), Karl Schwarschild Strasse 2, D-85748, Garching bei München (Germany); Sternberg, A. [Max Planck Institute for Astrophysics, Karl Schwarzschild Strasse 1, D-85741 Garching bei München (Germany); Williams, R. E. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Gal-Yam, A. [Benoziyo Center for Astrophysics, Faculty of Physics, Weizmann Institute of Science, Rehovot 76100 (Israel); Leonard, D. C. [Department of Astronomy, San Diego State University, San Diego, CA 92182 (United States); Stritzinger, Maximilian [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Folatelli, Gastón, E-mail: mmp@lco.cl [Kavli Institute for the Physics and Mathematics of the Universe, Todai Institutes for Advanced Study, the University of Tokyo, Kashiwa 277-8583 (Japan); and others

    2013-12-10

    High-dispersion observations of the Na I D λλ5890, 5896 and K I λλ7665, 7699 interstellar lines, and the diffuse interstellar band at 5780 Å in the spectra of 32 Type Ia supernovae are used as an independent means of probing dust extinction. We show that the dust extinction of the objects where the diffuse interstellar band at 5780 Å is detected is consistent with the visual extinction derived from the supernova colors. This strongly suggests that the dust producing the extinction is predominantly located in the interstellar medium of the host galaxies and not in circumstellar material associated with the progenitor system. One quarter of the supernovae display anomalously large Na I column densities in comparison to the amount of dust extinction derived from their colors. Remarkably, all of the cases of unusually strong Na I D absorption correspond to 'Blueshifted' profiles in the classification scheme of Sternberg et al. This coincidence suggests that outflowing circumstellar gas is responsible for at least some of the cases of anomalously large Na I column densities. Two supernovae with unusually strong Na I D absorption showed essentially normal K I column densities for the dust extinction implied by their colors, but this does not appear to be a universal characteristic. Overall, we find the most accurate predictor of individual supernova extinction to be the equivalent width of the diffuse interstellar band at 5780 Å, and provide an empirical relation for its use. Finally, we identify ways of producing significant enhancements of the Na abundance of circumstellar material in both the single-degenerate and double-degenerate scenarios for the progenitor system.

  9. A frequent tyrosinase gene mutation associated with type I-A (tyroinase-negative) oculocutaneous albinism in Puerto Rico

    Energy Technology Data Exchange (ETDEWEB)

    Oetting, W.S.; Witkop, C.J. Jr.; Brown, S.A.; Fryer, J.P.; Bloom, K.E.; King, R.A. (Univ. of Minnesota, Minneapolis (United States)); Colomer, R. (Servicio Medico de Empressa de la ONCE, Canary Islands (Spain))

    1993-01-01

    The authors have determined the mutations in the tyrosinase gene from 12 unrelated Puerto Rican individuals who have type I-A (tyrosinase-negative) oculocutaneous albinism (OCA). All but one individual are of Hispanic descent. Nine individuals were homozygous for a missense mutation (G47D) in exon I at codon 47. Two individuals were heterozygous for the G47D mutation, with one having a missense mutation at codon 373 (T373K) in the homologous allele and the other having an undetermined mutation in the homologous allele. One individual with negroid features was homozygous for a nonsense mutation (W236X). The population migration between Puerto Rico and the Canary Islands is well recognized. Analysis of three individuals with OCA from the Canary Islands showed that one was a compound heterozygote for the G47D mutation and for a novel missense mutation (L216M), one was homozygous for a missense mutation (P81L), and one was heterozygous for the missense mutation P81L. The G47D and P81L missense mutations have been previously described in extended families in the United States. Haplotypes were determined using four polymorphisms linked to the tyrosinase locus. Haplotype analysis showed that the G47D mutation occurred on a single haplotype, consistent with a common founder for all individuals having this mutation. Two different haplotypes were found associated with the P81L mutation, suggesting that this may be either a recurring mutation for the tyrosinase gene or a recombination between haplotypes. 28 refs., 1 fig., 3 tabs.

  10. Adeno-Associated Virus-Mediated Correction of a Canine Model of Glycogen Storage Disease Type Ia

    Science.gov (United States)

    Weinstein, David A.; Correia, Catherine E.; Conlon, Thomas; Specht, Andrew; Verstegen, John; Onclin-Verstegen, Karine; Campbell-Thompson, Martha; Dhaliwal, Gurmeet; Mirian, Layla; Cossette, Holly; Falk, Darin J.; Germain, Sean; Clement, Nathalie; Porvasnik, Stacy; Fiske, Laurie; Struck, Maggie; Ramirez, Harvey E.; Jordan, Juan; Andrutis, Karl; Chou, Janice Y.; Byrne, Barry J.

    2010-01-01

    Abstract Glycogen storage disease type Ia (GSDIa; von Gierke disease; MIM 232200) is caused by a deficiency in glucose-6-phosphatase-α. Patients with GSDIa are unable to maintain glucose homeostasis and suffer from severe hypoglycemia, hepatomegaly, hyperlipidemia, hyperuricemia, and lactic acidosis. The canine model of GSDIa is naturally occurring and recapitulates almost all aspects of the human form of disease. We investigated the potential of recombinant adeno-associated virus (rAAV) vector-based therapy to treat the canine model of GSDIa. After delivery of a therapeutic rAAV2/8 vector to a 1-day-old GSDIa dog, improvement was noted as early as 2 weeks posttreatment. Correction was transient, however, and by 2 months posttreatment the rAAV2/8-treated dog could no longer sustain normal blood glucose levels after 1 hr of fasting. The same animal was then dosed with a therapeutic rAAV2/1 vector delivered via the portal vein. Two months after rAAV2/1 dosing, both blood glucose and lactate levels were normal at 4 hr postfasting. With more prolonged fasting, the dog still maintained near-normal glucose concentrations, but lactate levels were elevated by 9 hr, indicating that partial correction was achieved. Dietary glucose supplementation was discontinued starting 1 month after rAAV2/1 delivery and the dog continues to thrive with minimal laboratory abnormalities at 23 months of age (18 months after rAAV2/1 treatment). These results demonstrate that delivery of rAAV vectors can mediate significant correction of the GSDIa phenotype and that gene transfer may be a promising alternative therapy for this disease and other genetic diseases of the liver. PMID:20163245

  11. Adeno-associated virus-mediated correction of a canine model of glycogen storage disease type Ia.

    Science.gov (United States)

    Weinstein, David A; Correia, Catherine E; Conlon, Thomas; Specht, Andrew; Verstegen, John; Onclin-Verstegen, Karine; Campbell-Thompson, Martha; Dhaliwal, Gurmeet; Mirian, Layla; Cossette, Holly; Falk, Darin J; Germain, Sean; Clement, Nathalie; Porvasnik, Stacy; Fiske, Laurie; Struck, Maggie; Ramirez, Harvey E; Jordan, Juan; Andrutis, Karl; Chou, Janice Y; Byrne, Barry J; Mah, Cathryn S

    2010-07-01

    Glycogen storage disease type Ia (GSDIa; von Gierke disease; MIM 232200) is caused by a deficiency in glucose-6-phosphatase-alpha. Patients with GSDIa are unable to maintain glucose homeostasis and suffer from severe hypoglycemia, hepatomegaly, hyperlipidemia, hyperuricemia, and lactic acidosis. The canine model of GSDIa is naturally occurring and recapitulates almost all aspects of the human form of disease. We investigated the potential of recombinant adeno-associated virus (rAAV) vector-based therapy to treat the canine model of GSDIa. After delivery of a therapeutic rAAV2/8 vector to a 1-day-old GSDIa dog, improvement was noted as early as 2 weeks posttreatment. Correction was transient, however, and by 2 months posttreatment the rAAV2/8-treated dog could no longer sustain normal blood glucose levels after 1 hr of fasting. The same animal was then dosed with a therapeutic rAAV2/1 vector delivered via the portal vein. Two months after rAAV2/1 dosing, both blood glucose and lactate levels were normal at 4 hr postfasting. With more prolonged fasting, the dog still maintained near-normal glucose concentrations, but lactate levels were elevated by 9 hr, indicating that partial correction was achieved. Dietary glucose supplementation was discontinued starting 1 month after rAAV2/1 delivery and the dog continues to thrive with minimal laboratory abnormalities at 23 months of age (18 months after rAAV2/1 treatment). These results demonstrate that delivery of rAAV vectors can mediate significant correction of the GSDIa phenotype and that gene transfer may be a promising alternative therapy for this disease and other genetic diseases of the liver.

  12. Thoracic type Ia endoleak: direct percutaneous coil embolization of the aortic arch at the blood entry site after TEVAR and double-chimney stent-grafts

    International Nuclear Information System (INIS)

    Bangard, Christopher; Franke, Mareike; Maintz, David; Chang, De-Hua; Pfister, Roman; Deppe, Antje-Christin; Matoussevitch, Vladimir

    2014-01-01

    To introduce a novel percutaneous technique to stop blood entry at the lesser aortic arch curvature by coil embolisation in type Ia endoleak after TEVAR. A 61-year-old Marfan patient presented with type Ia endoleak of the aortic arch and a growing aortic arch pseudoaneurysm after TEVAR. Multiple preceding operations and interventions made an endovascular approach unsuccessful. Direct percutaneous puncture of the aneurysmal sac would have cured the sign, but not the cause of blood entry at the lesser curvature of the aortic arch. Direct CT-guided percutaneous puncture of the blood entry site in the aortic arch with fluoroscopically guided coil embolisation using detachable extra-long coils was successfully performed. Three weeks after the intervention, the patient developed fever because of superinfection of the pseudoaneurysm. The blood cultures and CT-guided mediastinal aspirate were sterile. After intravenous administration of antibiotics, the fever disappeared and the patient recovered. Six-month follow-up showed permanent closure of the endoleak and a shrinking aneurysmal sac. Direct percutaneous puncture of the aortic arch at the blood entry site of a thoracic type Ia endoleak after TEVAR and double-chimney stent-grafts with coil embolisation of the wedge-shaped space between the lesser aortic curvature and the stent-graft is possible. (orig.)

  13. A novel homozygous no-stop mutation in G6PC gene from a Chinese patient with glycogen storage disease type Ia.

    Science.gov (United States)

    Gu, Lei-Lei; Li, Xin-Hua; Han, Yue; Zhang, Dong-Hua; Gong, Qi-Ming; Zhang, Xin-Xin

    2014-02-25

    Glycogen storage disease type Ia (GSD-Ia) is an autosomal recessive genetic disorder resulting in hypoglycemia, hepatomegaly and growth retardation. It is caused by mutations in the G6PC gene encoding Glucose-6-phosphatase. To date, over 80 mutations have been identified in the G6PC gene. Here we reported a novel mutation found in a Chinese patient with abnormal transaminases, hypoglycemia, hepatomegaly and short stature. Direct sequencing of the coding region and splicing-sites in the G6PC gene revealed a novel no-stop mutation, p.*358Yext*43, leading to a 43 amino-acid extension of G6Pase. The expression level of mutant G6Pase transcripts was only 7.8% relative to wild-type transcripts. This mutation was not found in 120 chromosomes from 60 unrelated healthy control subjects using direct sequencing, and was further confirmed by digestion with Rsa I restriction endonuclease. In conclusion, we revealed a novel no-stop mutation in this study which expands the spectrum of mutations in the G6PC gene. The molecular genetic analysis was indispensable to the diagnosis of GSD-Ia for the patient. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Long-Term Efficacy Following Readministration of an Adeno-Associated Virus Vector in Dogs with Glycogen Storage Disease Type Ia

    Science.gov (United States)

    Demaster, Amanda; Luo, Xiaoyan; Curtis, Sarah; Williams, Kyha D.; Landau, Dustin J.; Drake, Elizabeth J.; Kozink, Daniel M.; Bird, Andrew; Crane, Bayley; Sun, Francis; Pinto, Carlos R.; Brown, Talmage T.; Kemper, Alex R.

    2012-01-01

    Abstract Glycogen storage disease type Ia (GSD-Ia) is the inherited deficiency of glucose-6-phosphatase (G6Pase), primarily found in liver and kidney, which causes life-threatening hypoglycemia. Dogs with GSD-Ia were treated with double-stranded adeno-associated virus (AAV) vectors encoding human G6Pase. Administration of an AAV9 pseudotyped (AAV2/9) vector to seven consecutive GSD-Ia neonates prevented hypoglycemia during fasting for up to 8 hr; however, efficacy eventually waned between 2 and 30 months of age, and readministration of a new pseudotype was eventually required to maintain control of hypoglycemia. Three of these dogs succumbed to acute hypoglycemia between 7 and 9 weeks of age; however, this demise could have been prevented by earlier readministration an AAV vector, as demonstrated by successful prevention of mortality of three dogs treated earlier in life. Over the course of this study, six out of nine dogs survived after readministration of an AAV vector. Of these, each dog required readministration on average every 9 months. However, two were not retreated until >34 months of age, while one with preexisting antibodies was re-treated three times in 10 months. Glycogen content was normalized in the liver following vector administration, and G6Pase activity was increased in the liver of vector-treated dogs in comparison with GSD-Ia dogs that received only with dietary treatment. G6Pase activity reached approximately 40% of normal in two female dogs following AAV2/9 vector administration. Elevated aspartate transaminase in absence of inflammation indicated that hepatocellular turnover in the liver might drive the loss of vector genomes. Survival was prolonged for up to 60 months in dogs treated by readministration, and all dogs treated by readministration continue to thrive despite the demonstrated risk for recurrent hypoglycemia and mortality from waning efficacy of the AAV2/9 vector. These preclinical data support the further translation of AAV

  15. The detonation of a sub-Chandrasekhar-mass white dwarf at the origin of the low-luminosity Type Ia supernova 1999by

    Science.gov (United States)

    Blondin, Stéphane; Dessart, Luc; Hillier, D. John

    2018-03-01

    While Chandrasekhar-mass (MCh) models with a low 56Ni yield can match the peak luminosities of fast-declining, 91bg-like Type Ia supernovae (SNe Ia), they systematically fail to reproduce their faster light-curve evolution. Here, we illustrate the impact of a low ejecta mass on the radiative display of low-luminosity SNe Ia, by comparing a sub-MCh model resulting from the pure central detonation of a C-O white dwarf (WD) to an MCh delayed-detonation model with the same 56Ni yield of 0.12 M⊙. Our sub-MCh model from a 0.90 M⊙ WD progenitor has a ˜5 d shorter rise time in the integrated UV-optical-IR (uvoir) luminosity, as well as in the B band, and a ˜20 per cent higher peak uvoir luminosity (˜1 mag brighter peak MB). This sub-MCh model also displays bluer maximum-light colours due to the larger specific heating rate, and larger post-maximum uvoir and B-band decline rates. The luminosity decline at nebular times is also more pronounced, reflecting the enhanced escape of gamma rays resulting from the lower density of the progenitor WD. The deficit of stable nickel in the innermost ejecta leads to a notable absence of forbidden lines of [Ni II] in the nebular spectra. In contrast, the MCh model displays a strong line due to [Ni II] 1.939 μm, which could in principle serve to distinguish between different progenitor scenarios. Our sub-MCh model offers an unprecedented agreement with optical and near-infrared observations of the 91bg-like SN 1999by, making a strong case for a WD progenitor significantly below the Chandrasekhar-mass limit for this event and other low-luminosity SNe Ia.

  16. The upstream enhancer elements of the G6PC promoter are critical for optimal G6PC expression in murine glycogen storage disease type Ia.

    Science.gov (United States)

    Lee, Young Mok; Pan, Chi-Jiunn; Koeberl, Dwight D; Mansfield, Brian C; Chou, Janice Y

    2013-11-01

    Glycogen storage disease type-Ia (GSD-Ia) patients deficient in glucose-6-phosphatase-α (G6Pase-α or G6PC) manifest impaired glucose homeostasis characterized by fasting hypoglycemia, growth retardation, hepatomegaly, nephromegaly, hyperlipidemia, hyperuricemia, and lactic acidemia. Two efficacious recombinant adeno-associated virus pseudotype 2/8 (rAAV8) vectors expressing human G6Pase-α have been independently developed. One is a single-stranded vector containing a 2864-bp of the G6PC promoter/enhancer (rAAV8-GPE) and the other is a double-stranded vector containing a shorter 382-bp minimal G6PC promoter/enhancer (rAAV8-miGPE). To identify the best construct, a direct comparison of the rAAV8-GPE and the rAAV8-miGPE vectors was initiated to determine the best vector to take forward into clinical trials. We show that the rAAV8-GPE vector directed significantly higher levels of hepatic G6Pase-α expression, achieved greater reduction in hepatic glycogen accumulation, and led to a better toleration of fasting in GSD-Ia mice than the rAAV8-miGPE vector. Our results indicated that additional control elements in the rAAV8-GPE vector outweigh the gains from the double-stranded rAAV8-miGPE transduction efficiency, and that the rAAV8-GPE vector is the current choice for clinical translation in human GSD-Ia. © 2013.

  17. Minimal hepatic glucose-6-phosphatase-α activity required to sustain survival and prevent hepatocellular adenoma formation in murine glycogen storage disease type Ia

    Science.gov (United States)

    Lee, Young Mok; Kim, Goo-Young; Pan, Chi-Jiunn; Mansfield, Brian C.; Chou, Janice Y.

    2015-01-01

    Glycogen storage disease type Ia (GSD-Ia), characterized by impaired glucose homeostasis and chronic risk of hepatocellular adenoma (HCA), is caused by a deficiency in glucose-6-phosphatase-α (G6Pase-α or G6PC) activity. In a previous 70–90 week-study, we showed that a recombinant adeno-associated virus (rAAV) vector-mediated gene transfer that restores more than 3% of wild-type hepatic G6Pase-α activity in G6pc−/− mice corrects hepatic G6Pase-α deficiency with no evidence of HCA. We now examine the minimal hepatic G6Pase-α activity required to confer therapeutic efficacy. We show that rAAV-treated G6pc−/− mice expressing 0.2% of wild-type hepatic G6Pase-α activity suffered from frequent hypoglycemic seizures at age 63–65 weeks but mice expressing 0.5–1.3% of wild-type hepatic G6Pase-α activity (AAV-LL mice) sustain 4–6 h of fast and grow normally to age 75–90 weeks. Despite marked increases in hepatic glycogen accumulation, the AAV-LL mice display no evidence of hepatic abnormalities, hepatic steatosis, or HCA. Interprandial glucose homeostasis is maintained by the G6Pase-α/glucose-6-phosphate transporter (G6PT) complex, and G6PT-mediated microsomal G6P uptake is the rate-limiting step in endogenous glucose production. We show that hepatic G6PT activity is increased in AAV-LL mice. These findings are encouraging for clinical studies of G6Pase-α gene-based therapy for GSD-Ia. PMID:26937391

  18. Minimal hepatic glucose-6-phosphatase-α activity required to sustain survival and prevent hepatocellular adenoma formation in murine glycogen storage disease type Ia

    Directory of Open Access Journals (Sweden)

    Young Mok Lee

    2015-06-01

    Full Text Available Glycogen storage disease type Ia (GSD-Ia, characterized by impaired glucose homeostasis and chronic risk of hepatocellular adenoma (HCA, is caused by a deficiency in glucose-6-phosphatase-α (G6Pase-α or G6PC activity. In a previous 70–90 week-study, we showed that a recombinant adeno-associated virus (rAAV vector-mediated gene transfer that restores more than 3% of wild-type hepatic G6Pase-α activity in G6pc−/− mice corrects hepatic G6Pase-α deficiency with no evidence of HCA. We now examine the minimal hepatic G6Pase-α activity required to confer therapeutic efficacy. We show that rAAV-treated G6pc−/− mice expressing 0.2% of wild-type hepatic G6Pase-α activity suffered from frequent hypoglycemic seizures at age 63–65 weeks but mice expressing 0.5–1.3% of wild-type hepatic G6Pase-α activity (AAV-LL mice sustain 4–6 h of fast and grow normally to age 75–90 weeks. Despite marked increases in hepatic glycogen accumulation, the AAV-LL mice display no evidence of hepatic abnormalities, hepatic steatosis, or HCA. Interprandial glucose homeostasis is maintained by the G6Pase-α/glucose-6-phosphate transporter (G6PT complex, and G6PT-mediated microsomal G6P uptake is the rate-limiting step in endogenous glucose production. We show that hepatic G6PT activity is increased in AAV-LL mice. These findings are encouraging for clinical studies of G6Pase-α gene-based therapy for GSD-Ia.

  19. Probing gas and dust in the tidal tail of NGC 5221 with the type Ia supernova iPTF16abc

    Science.gov (United States)

    Ferretti, R.; Amanullah, R.; Goobar, A.; Petrushevska, T.; Borthakur, S.; Bulla, M.; Fox, O.; Freeland, E.; Fremling, C.; Hangard, L.; Hayes, M.

    2017-10-01

    Context. Type Ia supernovae (SNe Ia) can be used to address numerous questions in astrophysics and cosmology. Due to their well known spectral and photometric properties, SNe Ia are well suited to study gas and dust along the lines-of-sight to the explosions. For example, narrow Na I D and Ca II H&K absorption lines can be studied easily, because of the well-defined spectral continuum of SNe Ia around these features. Aims: We aim to study the gas and dust along the line-of-sight to iPTF16abc, which occurred in an unusual location, in a tidal arm, 80 kpc from centre of the galaxy NGC 5221. Methods: Using a time-series of high-resolution spectra, we have examined narrow Na I D and Ca II H&K absorption features for variations in time, which would be indicative for circumstellar (CS) matter. Furthermore, we have taken advantage of the well known photometric properties of SNe Ia to determine reddening due to dust along the line-of-sight. Results: From the lack of variations in Na I D and Ca II H&K, we determine that none of the detected absorption features originate from the CS medium of iPTF16abc. While the Na I D and Ca II H&K absorption is found to be optically thick, a negligible amount of reddening points to a small column of interstellar dust. Conclusions: We find that the gas along the line-of-sight to iPTF16abc is typical of what might be found in the interstellar medium (ISM) within a galaxy. It suggests that we are observing gas that has been tidally stripped during an interaction of NGC 5221 with one of its neighbouring galaxies in the past 109 yr. In the future, the gas clouds could become the locations of star formation. On a longer time scale, the clouds might diffuse, enriching the circum-galactic medium (CGM) with metals. The gas profile along the line-of-sight should be useful for future studies of the dynamics of the galaxy group containing NGC 5221. Based on observations collected at the European Organisation for Astronomical Research in the Southern

  20. The Carnegie Supernova Project. I. Third Photometry Data Release of Low-redshift Type Ia Supernovae and Other White Dwarf Explosions

    Science.gov (United States)

    Krisciunas, Kevin; Contreras, Carlos; Burns, Christopher R.; Phillips, M. M.; Stritzinger, Maximilian D.; Morrell, Nidia; Hamuy, Mario; Anais, Jorge; Boldt, Luis; Busta, Luis; Campillay, Abdo; Castellón, Sergio; Folatelli, Gastón; Freedman, Wendy L.; González, Consuelo; Hsiao, Eric Y.; Krzeminski, Wojtek; Persson, Sven Eric; Roth, Miguel; Salgado, Francisco; Serón, Jacqueline; Suntzeff, Nicholas B.; Torres, Simón; Filippenko, Alexei V.; Li, Weidong; Madore, Barry F.; DePoy, D. L.; Marshall, Jennifer L.; Rheault, Jean-Philippe; Villanueva, Steven

    2017-11-01

    We present final natural-system optical (ugriBV) and near-infrared (YJH) photometry of 134 supernovae (SNe) with probable white dwarf progenitors that were observed in 2004-2009 as part of the first stage of the Carnegie Supernova Project (CSP-I). The sample consists of 123 Type Ia SNe, 5 Type Iax SNe, 2 super-Chandrasekhar SN candidates, 2 Type Ia SNe interacting with circumstellar matter, and 2 SN 2006bt-like events. The redshifts of the objects range from z=0.0037 to 0.0835; the median redshift is 0.0241. For 120 (90%) of these SNe, near-infrared photometry was obtained. Average optical extinction coefficients and color terms are derived and demonstrated to be stable during the five CSP-I observing campaigns. Measurements of the CSP-I near-infrared bandpasses are also described, and near-infrared color terms are estimated through synthetic photometry of stellar atmosphere models. Optical and near-infrared magnitudes of local sequences of tertiary standard stars for each supernova are given, and a new calibration of Y-band magnitudes of the Persson et al. standards in the CSP-I natural system is presented.

  1. YOUNG REMNANTS OF TYPE Ia SUPERNOVAE AND THEIR PROGENITORS: A STUDY OF SNR G1.9+0.3

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborti, Sayan; Childs, Francesca; Soderberg, Alicia, E-mail: schakraborti@post.harvard.edu [Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2016-03-01

    SNe Ia, with their remarkably homogeneous light curves and spectra, have been used as standardizable candles to measure the accelerating expansion of the universe. Yet, their progenitors remain elusive. Common explanations invoke a degenerate star (white dwarf) that explodes upon almost reaching the Chandrasekhar limit, by either steadily accreting mass from a companion star or violently merging with another degenerate star. We show that circumstellar interaction in young Galactic supernova remnants can be used to distinguish between these single and double degenerate (DD) progenitor scenarios. Here we propose a new diagnostic, the surface brightness index, which can be computed from theory and compared with Chandra and Very Large Array (VLA) observations. We use this method to demonstrate that a DD progenitor can explain the decades-long flux rise and size increase of the youngest known galactic supernova remnant (SNR), G1.9+0.3. We disfavor a single degenerate scenario for SNR G1.9+0.3. We attribute the observed properties to the interaction between a steep ejecta profile and a constant density environment. We suggest using the upgraded VLA, ASKAP, and MeerKAT to detect circumstellar interaction in the remnants of historical SNe Ia in the Local Group of galaxies. This may settle the long-standing debate over their progenitors.

  2. Magmatic garnet in the Cordilleran-type Galiléia granitoids of the Araçuaí belt (Brazil): Evidence for crystallization in the lower crust

    Science.gov (United States)

    Narduzzi, F.; Farina, F.; Stevens, G.; Lana, C.; Nalini, H. A.

    2017-06-01

    Magmatic garnet, together with epidote, is a rare mineral association in cordilleran-I-type granitoids and of special petrogenetic significance. The metaluminous to slightly peraluminous (ASI = 0.97-1.07) Galiléia batholith (Brazil) is a large (ca. 30,000 km2), Neoproterozoic (ca. 632-570 Ma) weakly foliated calc-alkaline granitoid body, characterized by the widespread occurrence of garnet (grossular 25-43 mol%) and epidote (pistacite 9.3-22.7 mol%). Field, petrographic and mineral chemical evidence indicates that garnet, epidote, biotite as well as white mica crystals (low-Si phengite), are magmatic. There is no difference in bulk rock major and trace element composition between the Galiléia granitoids and other garnet-free cordilleran-type granitoids worldwide. This evidence strongly suggests that the origin of the uncommon garnet + epidote parageneses is related to the conditions of magma crystallization, such as pressure, temperature and water content. Comparison between the mineral assemblages and mineral compositions from this study and those recorded in crystallization experiments on metaluminous calc-alkaline magmas, as well as within garnet-bearing metaluminous volcanic rocks and granitoids, indicates that the supersolidus coexistence of grossular-rich garnet, epidote and white mica is consistent with magma crystallization at pressures greater than 0.8 GPa (above 25 km depth) and at temperatures below 700 °C, i.e. near the water saturated solidus. Furthermore, resorption textures around garnet (plagioclase ± quartz coronas) and epidote suggest that these minerals have been partially consumed prior to complete crystallization. These findings demonstrate that at 630 Ma the crust underneath the Araçuaí Orogen was already at least 25-30 km thick and relatively cool. However, this contrasts with the marked high heat flow registered from the neighbour Carlos Chagas Batholith located 50 km to the east. In fact such granitoids record granulite

  3. Cervical Cancer Stage IA

    Science.gov (United States)

    ... historical Searches are case-insensitive Cervical Cancer Stage IA Add to My Pictures View /Download : Small: 720x576 ... Large: 3000x2400 View Download Title: Cervical Cancer Stage IA Description: Stage IA1 and IA2 cervical cancer; drawing ...

  4. Polar orientation of renal grafts within the proximal seal zone affects risk of early type IA endoleaks after chimney endovascular aneurysm repair.

    Science.gov (United States)

    Tran, Kenneth; Ullery, Brant W; Itoga, Nathan; Lee, Jason T

    2018-04-01

    The objective of this study was to describe the polar orientation of renal chimney grafts within the proximal seal zone and to determine whether graft orientation is associated with early type IA endoleak or renal graft compression after chimney endovascular aneurysm repair (ch-EVAR). Patients who underwent ch-EVAR with at least one renal chimney graft from 2009 to 2015 were included in this analysis. Centerline three-dimensional reconstructions were used to analyze postoperative computed tomography scans. The 12-o'clock polar position was set at the takeoff of the superior mesenteric artery. Relative polar positions of chimney grafts were recorded at the level of the renal artery ostium, at the mid-seal zone, and at the proximal edge of the graft fabric. Early type IA endoleaks were defined as evidence of a perigraft flow channel within the proximal seal zone. There were 62 consecutive patients who underwent ch-EVAR (35 double renal, 27 single renal) for juxtarenal abdominal aortic aneurysms with a mean follow-up of 31.2 months; 18 (29%) early type IA "gutter" endoleaks were identified. During follow-up, the majority of these (n = 13; 72%) resolved without intervention, whereas two patients required reintervention (3.3%). Estimated renal graft patency was 88.9% at 60 months. Left renal chimney grafts were most commonly at the 3-o'clock position (51.1%) at the ostium, traversing posteriorly to the 5- to 7-o'clock positions (55.5%) at the fabric edge. Right renal chimney grafts started most commonly at the 9-o'clock position (n = 17; 33.3%) and tended to traverse both anteriorly (11 to 1 o'clock; 39.2%) and posteriorly (5 to 7 o'clock; 29.4%) at the fabric edge. In the polar plane, the majority of renal chimney grafts (n = 83; 85.6%) traversed 90 degrees were independently associated with early type IA endoleaks (odds ratio, 11.5; 95% confidence interval, 2.1-64.8) even after controlling for other device and anatomic variables. Polar orientation of the chimney

  5. Results of the ANCHOR prospective, multicenter registry of EndoAnchors for type Ia endoleaks and endograft migration in patients with challenging anatomy.

    Science.gov (United States)

    Jordan, William D; Mehta, Manish; Varnagy, David; Moore, William M; Arko, Frank R; Joye, James; Ouriel, Kenneth; de Vries, Jean-Paul

    2014-10-01

    Proximal attachment site complications continue to occur after endovascular repair of abdominal aortic aneurysms (EVAR), specifically type Ia endoleak and endograft migration. EndoAnchors (Aptus Endosystems, Sunnyvale, Calif) were designed to enhance endograft proximal fixation and sealing, and the current study was undertaken to evaluate the potential benefit of this treatment. During the 23-month period ending in December 2013, 319 subjects were enrolled at 43 sites in the United States and Europe. EndoAnchors were implanted in 242 patients (75.9%) at the time of an initial EVAR procedure (primary arm) and in 77 patients with an existing endograft and proximal aortic neck complications (revision arm). Technical success was defined as deployment of the desired number of EndoAnchors, adequate penetration of the vessel wall, and absence of EndoAnchor fracture. Procedural success was defined as technical success without a type Ia endoleak at completion angiography. Values are expressed as mean ± standard deviation and interquartile range. The 238 male (74.6%) and 81 female (25.4%) subjects had a mean age of 74.1 ± 8.2 years. Aneurysms averaged 58 ± 13 (51-63) mm in diameter at the time of EndoAnchor implantation (core laboratory measurements). The proximal aortic neck averaged 16 ± 13 (7-23) mm in length (42.7% <10 mm and 42.7% conical) and 27 ± 4 mm (25-30 mm) in diameter; infrarenal neck angulation was 24 ± 15 (13-34) degrees. The number of EndoAnchors deployed was 5.8 ± 2.1 (4-7). Technical success was achieved in 303 patients (95.0%) and procedural success in 279 patients (87.5%), 217 of 240 (89.7%) and 62 of 77 (80.5%) in the primary and revision arms, respectively. There were 29 residual type Ia endoleaks (9.1%) at the end of the procedure. During mean follow-up of 9.3 ± 4.7 months, 301 patients (94.4%) were free from secondary procedures. Among the 18 secondary procedures, eight were performed for residual type Ia endoleaks and the others

  6. On the type Ia supernovae 2007on and 2011iv: Evidence for Chandrasekhar-mass explosions at the faint end of the luminosity-width relationship.

    Science.gov (United States)

    Ashall, C.; Mazzali, P. A.; Stritzinger, M. D.; Hoeflich, P.; Burns, C. R.; Gall, C.; Hsiao, E. Y.; Phillips, M. M.; Morrell, N.; Foley, Ryan J.

    2018-03-01

    Radiative transfer models of two transitional type Ia supernova (SNe Ia) have been produced using the abundance stratification technique. These two objects -designated SN 2007on and SN 2011iv- both exploded in the same galaxy, NGC 1404, which allows for a direct comparison. SN 2007on synthesised 0.25 M⊙ of 56Ni and was less luminous than SN 2011iv, which produced 0.31 M⊙ of 56Ni. SN 2007on had a lower central density (ρc) and higher explosion energy (Ekin ˜1.3 ± 0.3 × 1051erg) than SN 2011iv, and it produced less nuclear statistical equilibrium (NSE) elements (0.06 M⊙). Whereas, SN 2011iv had a larger ρc, which increased the electron capture rate in the lowest velocity regions, and produced 0.35 M⊙ of stable NSE elements. SN 2011iv had an explosion energy of ˜Ekin ˜0.9 ± 0.2 × 1051erg. Both objects had an ejecta mass consistent with the Chandrasekhar mass (Ch-mass), and their observational properties are well described by predictions from delayed-detonation explosion models. Within this framework, comparison to the sub-luminous SN 1986G indicates SN 2011iv and SN 1986G have different transition densities (ρtr) but similar ρc. Whereas, SN 1986G and SN 2007on had a similar ρtr but different ρc. Finally, we examine the colour-stretch parameter sBV vs. Lmax relation and determine that the bulk of SNe Ia (including the sub-luminous ones) are consistent with Ch-mass delayed-detonation explosions, where the main parameter driving the diversity is ρtr. We also find ρc to be driving the second order scatter observed at the faint end of the luminosity-width relationship.

  7. The nebular spectra of the transitional Type Ia Supernovae 2007on and 2011iv: broad, multiple components indicate aspherical explosion cores

    Science.gov (United States)

    Mazzali, P. A.; Ashall, C.; Pian, E.; Stritzinger, M. D.; Gall, C.; Phillips, M. M.; Höflich, P.; Hsiao, E.

    2018-02-01

    The nebular-epoch spectrum of the rapidly declining, "transitional" type Ia supernova (SN) 2007on showed double emission peaks, which have been interpreted as indicating that the SN was the result of the direct collision of two white dwarfs. The spectrum can be reproduced using two distinct emission components, one red-shifted and one blue-shifted. These components are similar in mass but have slightly different degrees of ionization. They recede from one another at a line-of-sight speed larger than the sum of the combined expansion velocities of their emitting cores, thereby acting as two independent nebulae. While this configuration appears to be consistent with the scenario of two white dwarfs colliding, it may also indicate an off-centre delayed detonation explosion of a near Chandrasekhar-mass white dwarf. In either case, broad emission line widths and a rapidly evolving light curve can be expected for the bolometric luminosity of the SN. This is the case for both SNe 2007on and 2011iv, also a transitional SN Ia which exploded in the same elliptical galaxy, NGC 1404. Although SN 2011iv does not show double-peaked emission line profiles, the width of its emission lines is such that a two-component model yields somewhat better results than a single-component model. Most of the mass ejected is in one component, however, which suggests that SN 2011iv was the result of the off-centre ignition of a Chandrasekhar-mass white dwarf.

  8. The nebular spectra of the transitional Type Ia Supernovae 2007on and 2011iv: broad, multiple components indicate aspherical explosion cores

    Science.gov (United States)

    Mazzali, P. A.; Ashall, C.; Pian, E.; Stritzinger, M. D.; Gall, C.; Phillips, M. M.; Höflich, P.; Hsiao, E.

    2018-05-01

    The nebular-epoch spectrum of the rapidly declining, `transitional' Type Ia supernova (SN) 2007on showed double emission peaks, which have been interpreted as indicating that the SN was the result of the direct collision of two white dwarfs. The spectrum can be reproduced using two distinct emission components, one redshifted and one blueshifted. These components are similar in mass but have slightly different degrees of ionization. They recede from one another at a line-of-sight speed larger than the sum of the combined expansion velocities of their emitting cores, thereby acting as two independent nebulae. While this configuration appears to be consistent with the scenario of two white dwarfs colliding, it may also indicate an off-centre delayed detonation explosion of a near-Chandrasekhar-mass white dwarf. In either case, broad emission line widths and a rapidly evolving light curve can be expected for the bolometric luminosity of the SN. This is the case for both SNe 2007on and 2011iv, also a transitional SN Ia that exploded in the same elliptical galaxy, NGC 1404. Although SN 2011iv does not show double-peaked emission line profiles, the width of its emission lines is such that a two-component model yields somewhat better results than a single-component model. Most of the mass ejected is in one component, however, which suggests that SN 2011iv was the result of the off-centre ignition of a Chandrasekhar-mass white dwarf.

  9. Oral administration of Lactococcus lactis-expressing heat shock protein 65 and tandemly repeated IA2P2 prevents type 1 diabetes in NOD mice.

    Science.gov (United States)

    Liu, Kun-Feng; Liu, Xiao-Rui; Li, Guo-Liang; Lu, Shi-Ping; Jin, Liang; Wu, Jie

    2016-06-01

    Type 1 diabetes mellitus (T1DM) is a chronic autoimmune disease characterized by the destruction of insulin-secreting β cells upon autoreactive T cell attack. Oral administration of autoantigens is an attractive approach to treating T1DM, but an effective carrier should be used in order to protect antigens. Lactococcus lactis, a safe engineering strain, was used for this task in the present study. Two recombinant L. lactis expressing protein HSP65-6IA2P2 were used and be investigated the effects and mechanisms against T1DM in NOD mice. Our findings demonstrate that recombinant L. lactis strains can successfully both deliver antigens to intestinal mucosa and maintain the epitopes for a long time in NOD mice. Oral administration of recombinant L. lactis could prevent hyperglycemia, improve glucose tolerance, and reduce insulitis by inhibiting antigen-specific proliferation of T cells, augmenting regulatory immune reactions, and balancing ratios of Th17/Tregs and Th1/Th2. These results prove that orally administrated L. lactis expressing HSP65-6IA2P2 is an effective approach for the prevention of T1DM in NOD mice. Copyright © 2016 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  10. BtcA, A class IA type III chaperone, interacts with the BteA N-terminal domain through a globular/non-globular mechanism.

    Directory of Open Access Journals (Sweden)

    Chen Guttman

    Full Text Available Bordetella pertussis, the etiological agent of "whooping cough" disease, utilizes the type III secretion system (T3SS to deliver a 69 kDa cytotoxic effector protein, BteA, directly into the host cells. As with other T3SS effectors, prior to its secretion BteA binds BtcA, a 13.9 kDa protein predicted to act as a T3SS class IA chaperone. While this interaction had been characterized for such effector-chaperone pairs in other pathogens, it has yet to be fully investigated in Bordetella. Here we provide the first biochemical proof that BtcA is indeed a class IA chaperone, responsible for the binding of BteA's N-terminal domain. We bring forth extensive evidence that BtcA binds its substrate effector through a dual-interface binding mechanism comprising of non-globular and bi-globular interactions at a moderate micromolar level binding affinity. We demonstrate that the non-globular interactions involve the first 31 N-terminal residues of BteA287 and their removal leads to destabilization of the effector-chaperone complex and lower binding affinities to BtcA. These findings represent an important first step towards a molecular understanding of BteA secretion and cell entry.

  11. Disease progression and search for monogenic diabetes among children with new onset type 1 diabetes negative for ICA, GAD- and IA-2 Antibodies

    Directory of Open Access Journals (Sweden)

    de Beaufort Carine

    2010-09-01

    Full Text Available Abstract Background To investigate disease progression the first 12 months after diagnosis in children with type 1 diabetes negative (AAB negative for pancreatic autoantibodies [islet cell autoantibodies(ICA, glutamic acid decarboxylase antibodies (GADA and insulinoma-associated antigen-2 antibodies (IA-2A]. Furthermore the study aimed at determining whether mutations in KCNJ11, ABCC8, HNF1A, HNF4A or INS are common in AAB negative diabetes. Materials and methods In 261 newly diagnosed children with type 1 diabetes, we measured residual β-cell function, ICA, GADA, and IA-2A at 1, 6 and 12 months after diagnosis. The genes KCNJ11, ABCC8, HNF1A, HNF4A and INS were sequenced in subjects AAB negative at diagnosis. We expressed recombinant K-ATP channels in Xenopus oocytes to analyse the functional effects of an ABCC8 mutation. Results Twenty-four patients (9.1% tested AAB negative after one month. Patients, who were AAB-negative throughout the 12-month period, had higher residual β-cell function (P = 0.002, lower blood glucose (P = 0.004, received less insulin (P = 0.05 and had lower HbA1c (P = 0.02 12 months after diagnosis. One patient had a heterozygous mutation leading to the substitution of arginine at residue 1530 of SUR1 (ABCC8 by cysteine. Functional analyses of recombinant K-ATP channels showed that R1530C markedly reduced the sensitivity of the K-ATP channel to inhibition by MgATP. Morover, the channel was highly sensitive to sulphonylureas. However, there was no effect of sulfonylurea treatment after four weeks on 1.0-1.2 mg/kg/24 h glibenclamide. Conclusion GAD, IA-2A, and ICA negative children with new onset type 1 diabetes have slower disease progression as assessed by residual beta-cell function and improved glycemic control 12 months after diagnosis. One out of 24 had a mutation in ABCC8, suggesting that screening of ABCC8 should be considered in patients with AAB negative type 1 diabetes.

  12. Effect of VSL#3 Probiotic in a Patient with Glycogen Storage Disease Type Ia and Irritable Bowel Disease-like Disease.

    Science.gov (United States)

    Carnero-Gregorio, Miguel; Molares-Vila, Alberto; Corbalán-Rivas, Alberte; Villaverde-Taboada, Carlos; Rodríguez-Cerdeira, Carmen

    2018-02-13

    Gut Inflammatory bowel disease (IBD) is a group of chronic gastrointestinal disorders characterised by relapsing and remitting inflammation of the gastrointestinal tract. The two most common types of IBDs are ulcerative colitis and Crohn's disease. Patients with glycogen storage disease (GSD) type Ia present with gastrointestinal symptoms such as recurrent abdominal pain, bloating and changes in stool form or frequency, which is clinically difficult to distinguish from IBD. We report the case of a 36-year-old man with GSD type Ia and IBD-like disease. A commercial probiotic (VSL#3®) was chosen as a nutritional supplement treatment because of its high content of microbial species and strains. Three different tests were performed: normal-dose, no-dose and half-dose tests. The study periods for the normal-dose, no-dose and half-dose tests were 4 weeks from the treatment initiation, 72 h from the end of the previous period and 4 weeks to 6 months after the end of the 72-h period, respectively. When the probiotic treatment was stopped, he experienced several symptoms similar to those before the start of the treatment. The intestinal symptoms were less severe with the half-dose nutritional supplement treatment than with no treatment. Probiotics may reduce the number of irritable gut episodes and improve the patient's well-being and overall quality of life. More studies are needed to determine whether the improvement in more severe cases of GSD is due mainly to changes in the composition of the gut microbiota, as in this patient.

  13. Determining mutations in G6PC and SLC37A4 genes in a sample of Brazilian patients with glycogen storage disease types Ia and Ib

    Directory of Open Access Journals (Sweden)

    Marcelo Paschoalete Carlin

    2013-01-01

    Full Text Available Glycogen storage disease (GSD comprises a group of autosomal recessive disorders characterized by deficiency of the enzymes that regulate the synthesis or degradation of glycogen. Types Ia and Ib are the most prevalent; while the former is caused by deficiency of glucose-6-phosphatase (G6Pase, the latter is associated with impaired glucose-6-phosphate transporter, where the catalytic unit of G6Pase is located. Over 85 mutations have been reported since the cloning of G6PC and SLC37A4 genes. In this study, twelve unrelated patients with clinical symptoms suggestive of GSDIa and Ib were investigated by using genetic sequencing of G6PC and SLC37A4 genes, being three confirmed as having GSD Ia, and two with GSD Ib. In seven of these patients no mutations were detected in any of the genes. Five changes were detected in G6PC, including three known point mutations (p.G68R, p.R83C and p.Q347X and two neutral mutations (c.432G > A and c.1176T > C. Four changes were found in SLC37A4: a known point mutation (p.G149E, a novel frameshift insertion (c.1338_1339insT, and two neutral mutations (c.1287G > A and c.1076-28C > T. The frequency of mutations in our population was similar to that observed in the literature, in which the mutation p.R83C is also the most frequent one. Analysis of both genes should be considered in the investigation of this condition. An alternative explanation to the negative results in this molecular study is the possibility of a misdiagnosis. Even with a careful evaluation based on laboratory and clinical findings, overlap with other types of GSD is possible, and further molecular studies should be indicated.

  14. Adiponectin levels correlate with the severity of hypertriglyceridaemia in glycogen storage disease Ia

    NARCIS (Netherlands)

    Bandsma, R. H. J.; Smit, G. P. A.; Reijngoud, D. -J.; Kuipers, F.

    2009-01-01

    Glycogen storage disease type Ia (GSD Ia) is characterized by severe hypercholesterolaemia and hypertriglyceridaemia. Little is known about the aetiology of the hyperlipidaemia in GSD Ia. Adipokines play an important regulatory role in lipid metabolism. We investigated whether adipokine

  15. Glycogen storage disease type Ia mice with less than 2% of normal hepatic glucose-6-phosphatase-α activity restored are at risk of developing hepatic tumors.

    Science.gov (United States)

    Kim, Goo-Young; Lee, Young Mok; Kwon, Joon Hyun; Cho, Jun-Ho; Pan, Chi-Jiunn; Starost, Matthew F; Mansfield, Brian C; Chou, Janice Y

    2017-03-01

    Glycogen storage disease type Ia (GSD-Ia), characterized by impaired glucose homeostasis and chronic risk of hepatocellular adenoma (HCA) and carcinoma (HCC), is caused by a deficiency in glucose-6-phosphatase-α (G6Pase-α or G6PC). We have previously shown that G6pc-/- mice receiving gene transfer mediated by rAAV-G6PC, a recombinant adeno-associated virus (rAAV) vector expressing G6Pase-α, and expressing 3-63% of normal hepatic G6Pase-α activity maintain glucose homeostasis and do not develop HCA/HCC. However, the threshold of hepatic G6Pase-α activity required to prevent tumor formation remained unknown. In this study, we constructed rAAV-co-G6PC, a rAAV vector expressing a codon-optimized (co) G6Pase-α and showed that rAAV-co-G6PC was more efficacious than rAAV-G6PC in directing hepatic G6Pase-α expression. Over an 88-week study, we showed that both rAAV-G6PC- and rAAV-co-G6PC-treated G6pc-/- mice expressing 3-33% of normal hepatic G6Pase-α activity (AAV mice) maintained glucose homeostasis, lacked HCA/HCC, and were protected against age-related obesity and insulin resistance. Of the eleven rAAV-G6PC/rAAV-co-G6PC-treated G6pc-/- mice harboring 0.9-2.4% of normal hepatic G6Pase-α activity (AAV-low mice), 3 expressing 0.9-1.3% of normal hepatic G6Pase-α activity developed HCA/HCC, while 8 did not (AAV-low-NT). Finally, we showed that the AAV-low-NT mice exhibited a phenotype indistinguishable from that of AAV mice expressing ≥3% of normal hepatic G6Pase-α activity. The results establish the threshold of hepatic G6Pase-α activity required to prevent HCA/HCC and show that GSD-Ia mice harboring <2% of normal hepatic G6Pase-α activity are at risk of tumor development. Published by Elsevier Inc.

  16. The Super-Remnant of the Recurrent Nova M31N 2008-12a - A Signpost to Type Ia Supernovae?

    Science.gov (United States)

    Darnley, Matt

    2017-08-01

    M31N 2008-12a is the single most important nova system in M31. With an unprecedented 9 observed eruptions in just 9 years, an ultra-high mass white dwarf, a high accretion rate, and low ejected mass, it is the leading pre-explosion Supernova Type Ia progenitor candidate in any galaxy. Our team uncovered a vast elliptical nebula, centred on the nova - a recurrent nova 'super-remnant', the relic of many thousands of past eruptions. State-of-the-art 'multi-cycle' nova eruption models have shown that a CO WD in a short-recurrence period nova does indeed grow towards the Chandrasekhar mass. Such models predict frequent He-flashes, ejecting significantly more mass at higher velocities, every few-hundred eruptions. Our Cycle 24 Halpha observations confirmed the association between the recurrent nova and its super-remnant, enabled the mapping of the gas density, and provided the first possible evidence of the proposed recurrent He-flashes - large scale 'ripples' in the super-remnant. We propose to utilize the unique high-spatial resolution capabilities of HST at visible wavelengths to obtain a series of deep [S II] images to: (i) uniquely trace the remnant shock structure; (ii) confirm the detection of the signature ripples laid down in the super-remnant by the recurrent He-flashes, hence (iii) constrain models of the super-remnant, allowing extrapolation to other systems, and (iv) validate long-term nova eruption models, and also (v) explore shaping mechanisms both by the nova process and surrounding ISM. The relics of He-flashes within the super-remnant would confirm the new single-degenerate WD growth model, providing crucial evidence in support of the nova pathway to SNe Ia.

  17. Evidence for sub-Chandrasekhar-mass progenitors of Type Ia supernovae at the faint end of the width-luminosity relation

    Science.gov (United States)

    Blondin, Stéphane; Dessart, Luc; Hillier, D. John; Khokhlov, Alexei M.

    2017-09-01

    The faster light-curve evolution of low-luminosity Type Ia supernovae (SNe Ia) suggests that they could result from the explosion of white dwarf (WD) progenitors below the Chandrasekhar mass (MCh). Here we present 1D non-local thermodynamic equilibrium time-dependent radiative transfer simulations of pure central detonations of carbon-oxygen WDs with a mass (Mtot) between 0.88 and 1.15 M⊙ and a 56Ni yield between 0.08 and 0.84 M⊙. Their lower ejecta density compared to MCh models results in a more rapid increase of the luminosity at early times and an enhanced γ-ray escape fraction past maximum light. Consequently, their bolometric light curves display shorter rise times and larger post-maximum decline rates. Moreover, the higher M(56Ni)/Mtot ratio at a given 56Ni mass enhances the temperature and ionization level in the spectrum-formation region for the less luminous models, giving rise to bluer colours at maximum light and a faster post-maximum evolution of the B - V colour. For sub-MCh models fainter than MB ≈ -18.5 mag at peak, the greater bolometric decline and faster colour evolution lead to a larger B-band post-maximum decline rate, ΔM15(B). In particular, all of our previously published MCh models (standard and pulsational delayed detonations) are confined to ΔM15(B) explosion of WDs whose mass is significantly below the Chandrasekhar limit.

  18. PROMPT Ia SUPERNOVAE ARE SIGNIFICANTLY DELAYED

    International Nuclear Information System (INIS)

    Raskin, Cody; Scannapieco, Evan; Rhoads, James; Della Valle, Massimo

    2009-01-01

    The time delay between the formation of a population of stars and the onset of type Ia supernovae (SNe Ia) sets important limits on the masses and nature of SN Ia progenitors. Here, we use a new observational technique to measure this time delay by comparing the spatial distributions of SNe Ia to their local environments. Previous work attempted such analyses encompassing the entire host of each SN Ia, yielding inconclusive results. Our approach confines the analysis only to the relevant portions of the hosts, allowing us to show that even so-called prompt SNe Ia that trace star formation on cosmic timescales exhibit a significant delay time of 200-500 million years. This implies that either the majority of Ia companion stars have main-sequence masses less than 3 M sun , or that most SNe Ia arise from double white dwarf binaries. Our results are also consistent with a SNe Ia rate that traces the white dwarf formation rate, scaled by a fixed efficiency factor.

  19. CRISPR-Cas type I-A Cascade complex couples viral infection surveillance to host transcriptional regulation in the dependence of Csa3b.

    Science.gov (United States)

    He, Fei; Vestergaard, Gisle; Peng, Wenfang; She, Qunxin; Peng, Xu

    2017-02-28

    CRISPR-Cas (clustered regularly interspaced short palindromic repeats and the associated genes) constitute adaptive immune systems in bacteria and archaea and they provide sequence specific immunity against foreign nucleic acids. CRISPR-Cas systems are activated by viral infection. However, little is known about how CRISPR-Cas systems are activated in response to viral infection or how their expression is controlled in the absence of viral infection. Here, we demonstrate that both the transcriptional regulator Csa3b, and the type I-A interference complex Cascade, are required to transcriptionally repress the interference gene cassette in the archaeon Sulfolobus. Csa3b binds to two palindromic repeat sites in the promoter region of the cassette and facilitates binding of the Cascade to the promoter region. Upon viral infection, loading of Cascade complexes onto crRNA-matching protospacers leads to relief of the transcriptional repression. Our data demonstrate a mechanism coupling CRISPR-Cas surveillance of protospacers to transcriptional regulation of the interference gene cassette thereby allowing a fast response to viral infection. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  20. TYPE Ia SUPERNOVA DISTANCE MODULUS BIAS AND DISPERSION FROM K-CORRECTION ERRORS: A DIRECT MEASUREMENT USING LIGHT CURVE FITS TO OBSERVED SPECTRAL TIME SERIES

    Energy Technology Data Exchange (ETDEWEB)

    Saunders, C.; Aldering, G.; Aragon, C.; Bailey, S.; Childress, M.; Fakhouri, H. K.; Kim, A. G. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Guy, J. [Laboratoire de Physique Nucléaire et des Hautes Énergies, Université Pierre et Marie Curie Paris 6, Université Paris Diderot Paris 7, CNRS-IN2P3, 4 Place Jussieu, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Chotard, N.; Copin, Y.; Gangler, E. [Université de Lyon, Université Lyon 1, CNRS/IN2P3, Institut de Physique Nucléaire de Lyon, 69622 Villeurbanne (France); Feindt, U.; Kerschhaggl, M.; Kowalski, M. [Physikalisches Institut, Universität Bonn, Nußallee 12, D-53115 Bonn (Germany); and others

    2015-02-10

    We estimate systematic errors due to K-corrections in standard photometric analyses of high-redshift Type Ia supernovae. Errors due to K-correction occur when the spectral template model underlying the light curve fitter poorly represents the actual supernova spectral energy distribution, meaning that the distance modulus cannot be recovered accurately. In order to quantify this effect, synthetic photometry is performed on artificially redshifted spectrophotometric data from 119 low-redshift supernovae from the Nearby Supernova Factory, and the resulting light curves are fit with a conventional light curve fitter. We measure the variation in the standardized magnitude that would be fit for a given supernova if located at a range of redshifts and observed with various filter sets corresponding to current and future supernova surveys. We find significant variation in the measurements of the same supernovae placed at different redshifts regardless of filters used, which causes dispersion greater than ∼0.05 mag for measurements of photometry using the Sloan-like filters and a bias that corresponds to a 0.03 shift in w when applied to an outside data set. To test the result of a shift in supernova population or environment at higher redshifts, we repeat our calculations with the addition of a reweighting of the supernovae as a function of redshift and find that this strongly affects the results and would have repercussions for cosmology. We discuss possible methods to reduce the contribution of the K-correction bias and uncertainty.

  1. CRISPR-Cas type I-A Cascade complex couples viral infection surveillance to host transcriptional regulation in the dependence of Csa3b

    Science.gov (United States)

    He, Fei; Vestergaard, Gisle; Peng, Wenfang; She, Qunxin

    2017-01-01

    Abstract CRISPR-Cas (clustered regularly interspaced short palindromic repeats and the associated genes) constitute adaptive immune systems in bacteria and archaea and they provide sequence specific immunity against foreign nucleic acids. CRISPR-Cas systems are activated by viral infection. However, little is known about how CRISPR-Cas systems are activated in response to viral infection or how their expression is controlled in the absence of viral infection. Here, we demonstrate that both the transcriptional regulator Csa3b, and the type I-A interference complex Cascade, are required to transcriptionally repress the interference gene cassette in the archaeon Sulfolobus. Csa3b binds to two palindromic repeat sites in the promoter region of the cassette and facilitates binding of the Cascade to the promoter region. Upon viral infection, loading of Cascade complexes onto crRNA-matching protospacers leads to relief of the transcriptional repression. Our data demonstrate a mechanism coupling CRISPR-Cas surveillance of protospacers to transcriptional regulation of the interference gene cassette thereby allowing a fast response to viral infection. PMID:27980065

  2. LIKELIHOOD-FREE COSMOLOGICAL INFERENCE WITH TYPE Ia SUPERNOVAE: APPROXIMATE BAYESIAN COMPUTATION FOR A COMPLETE TREATMENT OF UNCERTAINTY

    International Nuclear Information System (INIS)

    Weyant, Anja; Wood-Vasey, W. Michael; Schafer, Chad

    2013-01-01

    Cosmological inference becomes increasingly difficult when complex data-generating processes cannot be modeled by simple probability distributions. With the ever-increasing size of data sets in cosmology, there is an increasing burden placed on adequate modeling; systematic errors in the model will dominate where previously these were swamped by statistical errors. For example, Gaussian distributions are an insufficient representation for errors in quantities like photometric redshifts. Likewise, it can be difficult to quantify analytically the distribution of errors that are introduced in complex fitting codes. Without a simple form for these distributions, it becomes difficult to accurately construct a likelihood function for the data as a function of parameters of interest. Approximate Bayesian computation (ABC) provides a means of probing the posterior distribution when direct calculation of a sufficiently accurate likelihood is intractable. ABC allows one to bypass direct calculation of the likelihood but instead relies upon the ability to simulate the forward process that generated the data. These simulations can naturally incorporate priors placed on nuisance parameters, and hence these can be marginalized in a natural way. We present and discuss ABC methods in the context of supernova cosmology using data from the SDSS-II Supernova Survey. Assuming a flat cosmology and constant dark energy equation of state, we demonstrate that ABC can recover an accurate posterior distribution. Finally, we show that ABC can still produce an accurate posterior distribution when we contaminate the sample with Type IIP supernovae.

  3. ChIA-PET2: a versatile and flexible pipeline for ChIA-PET data analysis.

    Science.gov (United States)

    Li, Guipeng; Chen, Yang; Snyder, Michael P; Zhang, Michael Q

    2017-01-09

    ChIA-PET2 is a versatile and flexible pipeline for analyzing different types of ChIA-PET data from raw sequencing reads to chromatin loops. ChIA-PET2 integrates all steps required for ChIA-PET data analysis, including linker trimming, read alignment, duplicate removal, peak calling and chromatin loop calling. It supports different kinds of ChIA-PET data generated from different ChIA-PET protocols and also provides quality controls for different steps of ChIA-PET analysis. In addition, ChIA-PET2 can use phased genotype data to call allele-specific chromatin interactions. We applied ChIA-PET2 to different ChIA-PET datasets, demonstrating its significantly improved performance as well as its ability to easily process ChIA-PET raw data. ChIA-PET2 is available at https://github.com/GuipengLi/ChIA-PET2. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  4. No Contribution of GAD-65 and IA-2 Autoantibodies around Time of Diagnosis to the Increasing Incidence of Juvenile Type 1 Diabetes

    DEFF Research Database (Denmark)

    Thorsen, Steffen U.; Pipper, Christian B.; Mortensen, Henrik B.

    2016-01-01

    our 9-year study period. No trends in autoantibody positivity-in either patients or siblings-were found. Levels of GADA and IA-2A were significantly associated with HLA risk groups and GADA with age. Conclusion. The prevalence of positivity and the levels of GADA and IA-2A have not changed between...... associated antigen-2A (IA-2A) mirrored the 3.4% annual increase in incidence of T1D. Methods. From the Danish Childhood Diabetes Register, we randomly selected 500 patients and 500 siblings for GADA and IA-2A analysis (1997 through 2005). Blood samples were taken within three months after onset. A robust log......-normal regression model was used. Nine hundred children and adolescents had complete records and were included in the analysis. Cochran-Armitage test for trend was used to evaluate changes in prevalence of autoantibody positivity by period. Results. No significant changes in levels of GADA and IA-2A were found over...

  5. RESEARCH HIGHLIGHTS IN IAS

    Directory of Open Access Journals (Sweden)

    Marko Kreft

    2017-03-01

    Full Text Available We are reviewing and commenting highlights of the research published in Image Analysis and Stereology journal (IAS, volume 35, where 16 original research papers on image analysis, computer vision, modelling, and other approaches were published. We have reported on the precision of curve length estimation in the plane. Further, a focus was on a robust estimation technique for 3D point cloud registration. Next contribution in computer vision was on the accuracy of stereo matching algorithm based on illumination control. An attempt was also made to automatically diagnose prenatal cleft lip with representative key points and identify the type of defect in three-dimensional ultrasonography. Similarly, a new report is presenting estimation of torsion of digital curves in 3D images and next, the nuchal translucency by ultrasound is being analyzed. Also in ophthalmology, image analysis may help physicians to establish a correct diagnosis, which is supported by a new approach to measure tortuosity of retinal vessel. Another report of medical significance analyzed correlation of the shape parameters for characterization of images of corneal endothelium cells. Shape analysis is also an important topic in material science, e.g. in analyzing fine aggregates in concrete. As in concrete, in fiber reinforced composites image analysis may aid in improved quality, where the direction of fibers have decisive impact on properties. Automatic defect detection using a computer vision system improves productivity quality in industrial production, hence we report of a new Haar wavelet-based approach.

  6. A High-Resolution X-Ray and Optical Study of SN1006: Asymmetric Expansion and Small-Scale Structure in a Type Ia Supernova Remnant

    Science.gov (United States)

    Winkler, P. Frank; Williams, Brian J.; Reynolds, Stephen P.; Petre, Robert; Long, Knox S.; Katsuda, Satoru; Hwang, Una

    2014-01-01

    We introduce a deep (670 ks) X-ray survey of the entire SN 1006 remnant from the Chandra X-Ray Observatory, together with a deep Ha image of SN 1006 from the 4 m Blanco telescope at CTIO. Comparison with Chandra images from 2003 gives the first measurement of the X-ray proper motions around the entire periphery, carried out over a 9 yr baseline. We find that the expansion velocity varies significantly with azimuth. The highest velocity of approx.7400 km/s (almost 2.5 times that in the northwest (NW)) is found along the southeast (SE) periphery, where both the kinematics and the spectra indicate that most of the X-ray emission stems from ejecta that have been decelerated little, if at all. Asymmetries in the distribution of ejecta are seen on a variety of spatial scales. Si-rich ejecta are especially prominent in the SE quadrant, while O and Mg are more uniformly distributed, indicating large-scale asymmetries arising from the explosion itself. Neon emission is strongest in a sharp filament just behind the primary shock along the NWrim, where the pre-shock density is highest. Here the Ne is likely interstellar, while Ne within the shell may include a contribution from ejecta. Within the interior of the projected shell we find a few isolated "bullets" of what appear to be supernova ejecta that are immediately preceded by bowshocks seen in Ha, features that we interpret as ejecta knots that have reached relatively dense regions of the surrounding interstellar medium, but that appear in the interior in projection. Recent three-dimensional hydrodynamic models for Type Ia supernovae display small-scale features that strongly resemble the ones seen in X-rays in SN 1006; an origin in the explosion itself or from subsequent hydrodynamic instabilities both remain viable options. We have expanded the search for precursor X-ray emission ahead of a synchrotron-dominated shock front, as expected from diffusive shock acceleration theory, to numerous regions along both the

  7. THE POST-MERGER MAGNETIZED EVOLUTION OF WHITE DWARF BINARIES: THE DOUBLE-DEGENERATE CHANNEL OF SUB-CHANDRASEKHAR TYPE Ia SUPERNOVAE AND THE FORMATION OF MAGNETIZED WHITE DWARFS

    International Nuclear Information System (INIS)

    Ji Suoqing; Fisher, Robert T.; García-Berro, Enrique; Tzeferacos, Petros; Jordan, George; Lee, Dongwook; Lorén-Aguilar, Pablo; Cremer, Pascal; Behrends, Jan

    2013-01-01

    Type Ia supernovae (SNe Ia) play a crucial role as standardizable cosmological candles, though the nature of their progenitors is a subject of active investigation. Recent observational and theoretical work has pointed to merging white dwarf binaries, referred to as the double-degenerate channel, as the possible progenitor systems for some SNe Ia. Additionally, recent theoretical work suggests that mergers which fail to detonate may produce magnetized, rapidly rotating white dwarfs. In this paper, we present the first multidimensional simulations of the post-merger evolution of white dwarf binaries to include the effect of the magnetic field. In these systems, the two white dwarfs complete a final merger on a dynamical timescale, and are tidally disrupted, producing a rapidly rotating white dwarf merger surrounded by a hot corona and a thick, differentially rotating disk. The disk is strongly susceptible to the magnetorotational instability (MRI), and we demonstrate that this leads to the rapid growth of an initially dynamically weak magnetic field in the disk, the spin-down of the white dwarf merger, and to the subsequent central ignition of the white dwarf merger. Additionally, these magnetized models exhibit new features not present in prior hydrodynamic studies of white dwarf mergers, including the development of MRI turbulence in the hot disk, magnetized outflows carrying a significant fraction of the disk mass, and the magnetization of the white dwarf merger to field strengths ∼2 × 10 8 G. We discuss the impact of our findings on the origins, circumstellar media, and observed properties of SNe Ia and magnetized white dwarfs

  8. IA, I AM

    DEFF Research Database (Denmark)

    Munk, Timme Bisgaard; Mørk, Kristian

    2004-01-01

    Hvad er informationsarkitektur? Mørk & Munk gennemgår de forskellige metaforiske konstruktioner af begrebet og kommer med deres helt egen selvstændige definition. Informationsarkitektur er en samtale, strukturation, en klassifikationskamp og et konceptuelt blend. Læs hvorfor i dette working paper...... om et af de meste centrale begreber videnssamfundet. For nu er vi alle informationsarkitekter: IA, I AM....

  9. SNe Ia: Can Chandrasekhar mass explosions reproduce the observed zoo?

    Energy Technology Data Exchange (ETDEWEB)

    Baron, E. [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 400 W. Brooks, Rm 100, Norman, OK 73072-2061 (United States); Hamburger Sternwarte, Gojenbergsweg 112, 21029 Hamburg (Germany)

    2014-08-15

    The question of the nature of the progenitor of Type Ia supernovae (SNe Ia) is important both for our detailed understanding of stellar evolution and for their use as cosmological probes of the dark energy. Much of the basic features of SNe Ia can be understood directly from the nuclear physics, a fact which Gerry would have appreciated. We present an overview of the current observational and theoretical situation and show that it not incompatible with most SNe Ia being the results of thermonuclear explosions near the Chandrasekhar mass.

  10. Avaliação de diferentes modelos de colméias para abelhas jataí (Tetragonisca angustula Latreille, 1811 Evaluation of different types of stingless bees hives (Tetragonisca angustula Latreille, 1811

    Directory of Open Access Journals (Sweden)

    Maria Claudia Colla Ruvolo-Takasusuki

    2002-04-01

    Full Text Available O objetivo deste trabalho foi avaliar o desempenho de colônias de abelhas jataís, Tetragonisca angustula Latreille, 1811 (Hymenoptera, Meliponinae na região de Maringá, Estado do Paraná, alojadas nos seguintes modelos de colméia: Fritzen, Guiliani, Nogueira-Neto e Antonio Carlos Farias (ACF. O experimento foi realizado no período de dezembro de 1999 a dezembro de 2000, com 20 colônias. Mensalmente, as colméias foram pesadas e obtendo-se o peso da colônia. Os dados foram analisados estatisticamente utilizando o mês como co-variável e o teste de Scheffe para comparação das médias. As colônias alojadas em colméias dos modelos Guiliani e Nogueira-Neto apresentaram um melhor desenvolvimento diferindo (p = 0,0004 das colônias alojadas nos modelos Fritzen e ACF. O peso médio das colônias foi de 387,3 ± 92,2g, 375,8 ± 72,6g, 241,2 ± 137,1g e 230,9 ± 55,3g, respectivamente, para as alojadas nos modelos Guiliani, Nogueira-Neto, ACF e Fritzen. Os meses críticos foram março e maio de 2000, nos quais ocorreram oito mortes e oito abandonos. Pode-se verificar que as colônias mantidas nas colméias Guiliani e Nogueira-Neto apresentaram uma maior uniformidade no peso. Portanto, pode-se concluir que os modelos de colméias Guiliani e Nogueira-Neto seriam os mais recomendados para a região de Maringá, Estado do Paraná.This research was carried out to evaluate the performance of stingless bees' colonies, Tetragonisca angustula Latreille, 1811 (Hymenoptera, Meliponinae, in Maringá region in the south of Brazil. Twenty colonies were settled in the following types of hives: Fritzen, Guiliani, Nogueira-Neto, and Antonio Carlos Farias (ACF, with five replications each type. The experimental season was from December, 1999 to December 2000. Monthly, the hives were weighed in order to get the colony weight. Data were analyzed statistically using the month as co variable and Scheffes’s test to compare the means. The colonies settled in

  11. Optimizing IA-64 performance

    CERN Document Server

    Jarp, S

    2001-01-01

    Examines key features of the Itanium processor architecture and microarchitecture. The Itanium, originally known as the IA-64, is a 64-bit processor designed by Hewlett-Packard and Intel. In addition to the obvious performance gains that 64-bit addressing brings, the Itanium also supports performance-enhancing techniques such as predication, speculation, rotating registers, a wide parallel execution core, high clock speed, fast bus architecture, multiple execution units, and the like. Moreover, the Itanium is designed from the ground up around parallelism and uses a new kind of instruction set based on the Explicit Parallel Instruction Computing (EPIC) specification, which allows the processing of Windows-based and UNIX- based applications, among other features. Operating-system support for the IA-64 has been announced for 64-bit Windows, HP-UX, varieties of Linux, and AIX 51. The author shows how to achieve optimal code generation by a compiler or generate optimized sequences ofIA-64 assembly code to ensure ...

  12. Fixação esquelética externa tipo Ia (unilateral-uniplanar para osteossíntese diafisária de úmero em pombos domésticos (Columba livia Type Ia (unilateral-uniplanar external Skeletal fixation for treatment of humeral diaphysis fracture in domestic pigeons (Columba livia

    Directory of Open Access Journals (Sweden)

    Alessandro Moraes Leotte

    2004-12-01

    Full Text Available Das várias patologias que podem acometer as aves, são mais freqüentes as fraturas de ossos longos das asas e dos membros pélvicos. Este experimento teve como objetivo observar, por meio de exames clínicos, histológicos e radiográficos, a resposta cicatricial óssea ao uso do fixador externo tipo Ia (unilateral-uniplanar na redução aberta de fratura diafisária, de úmero em pombos domésticos (Columba livia. Foram estudados 14 pombos com peso variando entre 290 e 420 gramas. A fratura foi realizada na diáfise do úmero direito e, logo após, estabilizada com aparelho de fixação externa tipo Ia, utilizando-se, como barra de fixação, o acrílico autopolimerizável. O tempo médio para o completo desaparecimento da linha de fratura foi de 28±6,44 dias e para formação de calo ósseo, 17±3,26 dias. As aves, mesmo com o aparelho de fixação, retornaram ao vôo aos 28±1,2 dias, exceto uma que não recuperou a capacidade de vôo. A técnica de fixação externa demonstrou ser eficaz para o tratamento de fraturas diafisárias de úmero em pombos domésticos.Among the various pathologies that can inflict birds, the long bones fractures of the wings, and pelvic members are more commom. Fourteeen domestic pigeons (Columba livia weighing 290 to 420g, were submitted to open reduction of humeral diaphysis fracture with external fixator type Ia (unilateral-uniplanar in order to evaluate the clinical, histological and radiographic evolution of the bone healing. The external fixator device was stabilized with methilmetacrylate acrylic. The average time necessary to the complete disappearance of the fracture line by radiographic evaluation was 28±6.44 days. The bone callus was identified at 17±3.26 postoperative days. The birds returned to flying in 28±1.2 days yet with the fixation device and only one did not recovere the flying abillity. The external fixation technique is an efficient method to treat diaphiseal humeral fracture in domestic

  13. The dense core vesicle protein IA-2, but not IA-2β, is required for active avoidance learning.

    Science.gov (United States)

    Carmona, G N; Nishimura, T; Schindler, C W; Panlilio, L V; Notkins, A L

    2014-06-06

    The islet-antigens IA-2 and IA-2β are major autoantigens in type-1 diabetes and transmembrane proteins in dense core vesicles (DCV). Recently we showed that deletion of both IA-2 and IA-2β alters the secretion of hormones and neurotransmitters and impairs behavior and learning. The present study was designed to evaluate the contribution to learning of each of these genes by using single knockout (SKO) and double knockout (DKO) mice in an active avoidance test. After 5 days of training, wild-type (WT) mice showed 60-70% active avoidance responses, whereas the DKO mice showed only 10-15% active avoidance responses. The degree of active avoidance responses in the IA-2 SKO mice was similar to that of the DKO mice, but in contrast, the IA-2β SKO mice behaved like WT mice showing 60-70% active avoidance responses. Molecular studies revealed a marked decrease in the phosphorylation of the cAMP response element-binding protein (CREB) and Ca(2+)/calmodulin-dependent protein kinase II (CAMKII) in the striatum and hippocampus of the IA-2 SKO and DKO mice, but not in the IA-2β SKO mice. To evaluate the role of CREB and CAMKII in the SKO and DKO mice, GBR-12909, which selectively blocks the dopamine uptake transporter and increases CREB and CAMKII phosphorylation, was administered. GBR-12909 restored the phosphorylation of CREB and CAMKII and increased active avoidance learning in the DKO and IA-2 SKO to near the normal levels found in the WT and IA-2β SKO mice. We conclude that in the absence of the DCV protein IA-2, active avoidance learning is impaired. Published by Elsevier Ltd.

  14. Removal of a frameshift between the hsdM and hsdS genes of the EcoKI Type IA DNA restriction and modification system produces a new type of system and links the different families of Type I systems

    Science.gov (United States)

    Roberts, Gareth A.; Chen, Kai; Cooper, Laurie P.; White, John H.; Blakely, Garry W.; Dryden, David T. F.

    2012-01-01

    The EcoKI DNA methyltransferase is a trimeric protein comprised of two modification subunits (M) and one sequence specificity subunit (S). This enzyme forms the core of the EcoKI restriction/modification (RM) enzyme. The 3′ end of the gene encoding the M subunit overlaps by 1 nt the start of the gene for the S subunit. Translation from the two different open reading frames is translationally coupled. Mutagenesis to remove the frameshift and fuse the two subunits together produces a functional RM enzyme in vivo with the same properties as the natural EcoKI system. The fusion protein can be purified and forms an active restriction enzyme upon addition of restriction subunits and of additional M subunit. The Type I RM systems are grouped into families, IA to IE, defined by complementation, hybridization and sequence similarity. The fusion protein forms an evolutionary intermediate form lying between the Type IA family of RM enzymes and the Type IB family of RM enzymes which have the frameshift located at a different part of the gene sequence. PMID:23002145

  15. Removal of a frameshift between the hsdM and hsdS genes of the EcoKI Type IA DNA restriction and modification system produces a new type of system and links the different families of Type I systems.

    Science.gov (United States)

    Roberts, Gareth A; Chen, Kai; Cooper, Laurie P; White, John H; Blakely, Garry W; Dryden, David T F

    2012-11-01

    The EcoKI DNA methyltransferase is a trimeric protein comprised of two modification subunits (M) and one sequence specificity subunit (S). This enzyme forms the core of the EcoKI restriction/modification (RM) enzyme. The 3' end of the gene encoding the M subunit overlaps by 1 nt the start of the gene for the S subunit. Translation from the two different open reading frames is translationally coupled. Mutagenesis to remove the frameshift and fuse the two subunits together produces a functional RM enzyme in vivo with the same properties as the natural EcoKI system. The fusion protein can be purified and forms an active restriction enzyme upon addition of restriction subunits and of additional M subunit. The Type I RM systems are grouped into families, IA to IE, defined by complementation, hybridization and sequence similarity. The fusion protein forms an evolutionary intermediate form lying between the Type IA family of RM enzymes and the Type IB family of RM enzymes which have the frameshift located at a different part of the gene sequence.

  16. Cataclysmic Variables as Supernova Ia Progenitors

    Directory of Open Access Journals (Sweden)

    Stella Kafka

    2012-06-01

    Full Text Available Although the identification of the progenitors of type Ia supernovae (SNeIa remains controversial, it is generally accepted that they originate from binary star systems in which at least one component is a carbon-oxygen white dwarf (WD; those systems are grouped under the wide umbrella of cataclysmic variables. Current theories for SNeIa progenitors hold that, either via Roche lobe overflow of the companion or via a wind, the WD accumulates hydrogen or helium rich material which is then burned to C and O onto the WD’s surface. However, the specifics of this scenario are far from being understood or defined, allowing for a wealth of theories fighting for attention and a dearth of observations to support them. I discuss the latest attempts to identify and study those controversial SNeIa progenitors. I also introduce the most promising progenitor in hand and I present observational diagnostics that can reveal more members of the category.

  17. Content of Diabetes-Associated Autoantibodies against Islet Autoantigens (IA-2A, GADA, IAA and the Level of Different Cytokines in Children and Adolescents on the Pre-Clinical and Early Clinical Stages of Type 1 Diabetes Mellitus Development

    Directory of Open Access Journals (Sweden)

    V.V. Popova

    2015-03-01

    Full Text Available The article provides the data on the immunological mechanisms of type 1 diabetes mellitus (T1DM on the preclinical and early clinical stages of disease formation on the basis of studying the features of T1DM pathogenesis, monitoring the process of autoimmune destruction of insulin-producing β-cells by determining the content of diabetes-associated auto-antibodies (the incidence and titers dynamics, the study of the characteristics of cytokine secretion on the pre-clinical stage of T1DM development in children and adolescents. Introduction of new approaches to pre-clinical diagnosis of T1DM allowed determine the group of marker-positive children with burdened heredity and predictable risk of disease development. The study involved 450 healthy normoglycemic children and adolescents aged from 7 to 15 years old. It was revealed that 94 (26.7 % of 366 children with burdened hereditary by at least two-fold determination of DAAb had an increased DAAb titer, mainly GADA and IA-2A, the clinical debut of T1DM manifested in 49 (52.1 % of them from 6 months to 12 years (30.9 ± 3.2 months. T1DM developed in the same period in a child, that was 0.8 % of the 272 (73.3 % DAAb-negative children. There was determined a formula of combined incidence and values of simultaneously elevated DAAb titers to islet autoantigens, namely IA-2A + GADA, which are predictor of the duration of T1DM pre-clinical stage and debut occurrence. It has been also established a disturbance of cytokine production (increased level of pro-inflammatory cytokines IL-1α, IL-6 and FNO-α, IL-8 and IL-16 while reduced concentration of IL-4 in blood plasma as a key factor in the T1DM pathogenesis that causes the debut occurrence, and aggressiveness of its course.

  18. Serum titres of anti-glutamic acid decarboxylase-65 and anti-IA-2 autoantibodies are associated with different immunoregulatory milieu in newly diagnosed type 1 diabetes patients

    OpenAIRE

    Gabbay, Monica Andrade Lima [UNIFESP; Sato, M. N.; Duarte, A. J. S.; Dib, Sergio Atala [UNIFESP

    2012-01-01

    Several studies correlated genetic background and pancreatic islet-cell autoantibody status (type and number) in type 1A diabetes mellitus (T1AD), but there are no data evaluating the relationship among these markers with serum cytokines, regulatory T cells and beta cell function. This characterization has a potential importance with regard to T1AD patients' stratification and follow-up in therapeutic prevention. in this study we showed that peripheral sera cytokines [interleukin (IL)-12, IL-...

  19. Impact de Ia chimioprophylaxie au cotrimoxazole sur Ia morbidite ...

    African Journals Online (AJOL)

    Impact de Ia chimioprophylaxie au cotrimoxazole sur Ia morbidite infectieuse non palustre chez des adultes Ouest Africains vivant avec le VIH. ... A I' inclusion le taux de CD4 moyen etait de 287,9 ce1l/mm3 et la charge virale moyenne etait de 5,8 log10. Les 2/3 des patients ont ete rnis sous traitement antiretroviral.

  20. Comparative pharmacokinetics and bioavailability of escin Ia and isoescin Ia after administration of escin and of pure escin Ia and isoescin Ia in rat.

    Science.gov (United States)

    Wu, Xiu-Jun; Zhang, Meng-Liang; Cui, Xiang-Yong; Gao, Feng; He, Qun; Li, Xiao-Jiao; Zhang, Ji-Wen; Fawcett, J Paul; Gu, Jing-Kai

    2012-01-06

    Escin Ia and isoescin Ia have been traditionally used clinically as the chief active ingredients of escin, a major triterpene saponin isolated from horse chestnut (Aesculus hippocastanum) seeds for the treatment of chronic venous insufficiency, hemorrhoids, inflammation and edema. To establish a sensitive LC-MS/MS method and investigate the pharmacokinetic properties of escin Ia and isoescin Ia in rats and the pharmacokinetics difference of sodium escinate with pure escin Ia and isoescin Ia. The absolute bioavailability of escin Ia and isoescin Ia and the bidirectional interconversion of them in vivo were also scarcely reported. Wister rats were administrated an intravenous (i.v.) dose (1.7 mg/kg) of sodium escinate (corresponding to 0.5mg/kg of escin Ia and 0.5mg/kg of isoescin Ia, respectively) and an i.v. dose (0.5mg/kg) or oral dose (4mg/kg) of pure escin Ia or isoescin Ia, respectively. At different time points, the concentrations of escin Ia and isoescin Ia in rat plasma were determined by LC-MS/MS method. Main pharmacokinetic parameters including t(1/2), MRT, CL, V(d), AUC and F were estimated by non-compartmental analysis using the TopFit 2.0 software package (Thomae GmbH, Germany) and statistical analysis was performed using the Student's t-test with Pescinate, the t(1/2) and MRT values for both escin Ia and isoescin Ia were larger than corresponding values for the compounds given alone. Absorption of escin Ia and isoescin Ia was very low with F values both Escin Ia and isoescin Ia were found to form the other isomer in vivo with the conversion of escin Ia to isoescin Ia being much extensive than from isoescin Ia to escin Ia. Comparison of the pharmacokinetics of escin Ia and isoescin Ia given alone and together in rat suggest that administration of herbal preparations of escin for clinical use may provide longer duration of action than administration of single isomers. The interconversion of escin Ia and isoescin Ia when given alone indicates that

  1. A New Set of Nearby SNe Ia Lightcurves

    Science.gov (United States)

    Regnault, N.; Aldering, G.; Blanc, G.; Conley, A.; Dahlen, T.; Deustua, S.; Ellis, R.; Fan, X.; Folatelli, G.; Frye, B.; Garavini, G.; Gates, E.; Goldhaber, G.; Goldman, B.; Goobar, A.; Groom, D.; Hardin, D.; Hook, I.; Kent, S.; Kim, A.; Kim, M.; Knop, R.; Lidman, C.; Mendez, J.; Miller, G.; Moniez, M.; Mourao, A.; Newberg, H.; Nobili, S.; Nugent, P.; Pain, R.; Perdereau, O.; Perlmutter, S.; Quimby, R.; Rich, J.; Richards, G.; Ruiz-Lapuente, P.; Schaefer, B.; Walton, N.; Supernova Cosmology Project Collaboration

    2001-12-01

    Type Ia supernovae (SNe Ia) are powerful cosmological distance indicators and have been used for measuring cosmological parameters such as the Hubble constant, H0, and the mass density Ω m and dark energy density Ω Λ of the universe. These measurements rely on empirical correlations between absolute peak luminosities and other observables, like the postmaximum decline rate, and the color at maximum. Since the total number of well observed nearby Hubble flow SNe Ia is still small, these correlations are not yet fully characterized. In the Spring of 1999 the Supernova Cosmology Project undertook a nearby SN Ia search in collaboration with groups around the world. This campaign was aimed at providing an independent set of high quality light curves and spectra, to further study SN Ia properties, and fill the Hubble diagram at low redshift. 37 SNe were discovered, of which 19 were SNe Ia near or before maximum light, in the redshift range z=0.002 -- 0.15. These supernovae were followed-up photometrically and spectroscopically, using 20 different telescopes with apertures from 1-m to 10-m. We present the results of the very successful photometric follow-up. An average of 10 points was collected for each SN Ia in the B, V, R and I bands. In addition, we were able to obtain 5 well measured U-lightcurves. With this dataset, we are studying the correlations between the magnitude at maximum, the decline rate and the color at maximum. These systematic studies play a key role in the cosmological measurements using high redshift SNe Ia.

  2. Computed tomography scan of the head in patients with migraine or tension-type headache Tomografia computadorizada do crânio em pacientes com migrânea ou cefaléia tensional

    Directory of Open Access Journals (Sweden)

    Marcelo Moraes Valença

    2002-09-01

    Full Text Available A retrospective study was performed in order to evaluate the frequency of abnormalities found by computed tomography (CT scan of the head in 78 patients with migraine or tension-type headache. In the present study CT scan was normal in 61.5% of the patients with migraine or tension-type headache. A number of abnormalities were encountered in more than one third of the patients studied, including inflammatory sinus disease (19.2%, cysticercosis (3.9%, unruptuted cerebral aneurysm (2.6%, basilar impression (2.6%, intracranial lipoma (2.6%, arachnoid cyst (2.6%, empty sella (2.6%, intracranial neoplasm (2.6%, and others (2.6%. None of these lesions were symptomatic or responsible by the headache picture, therefore, considered incidental findings. In conclusion, the fortuitous encounter of some abnormalities on CT scan of the head is often higher than what we could predict in patients suffering migraine or tension-type headache. We briefly discuss clinical, epidemiologic, and practical management of some of the abnormalities detected by CT scan as well as the indication to request a neuroimaging investigation.Um estudo retrospectivo foi realizado visando avaliar a frequência de anormalidades encontradas durante a realização de estudo por tomografia computadorizada (TC em 78 pacientes com migrânea ou cefaléia do tipo tensional. A TC foi normal em 61,5% dos pacientes examinados. Em um terço dos pacientes estudados foram detectadas anormalidades, como doença inflamatória dos seios paranasais (19,2%, cisticercose (3,9%, aneurisma cerebral não-roto (2,6%, impressão basilar (2,6%, lipoma intracraniano (2,6%, cisto aracnoideo (2,6%, sela vazia (2,6%, neoplasia intracraniana (2,6% e outras afecções (2,6%. Nenhuma destas lesões era sintomática (achado incidental. Concluindo, o encontro fortuito de algumas anormalidades na TC é frequentemente mais elevado do que se prediz em pacientes com cefaléia primária. Nós discutimos brevemente alguns

  3. The first IA-64 microprocessor

    CERN Document Server

    Rusu, S

    2000-01-01

    The first implementation of the IA-64 architecture achieves high performance by using a highly parallel execution core, while maintaining binary compatibility with the IA-32 instruction set. Explicitly parallel instruction computing (EPIC) design maximizes performance through hardware and software synergy. The processor contains 25.4 million transistors and operates at 800 MHz. The chip is fabricated in a 0.18- mu m CMOS process with six metal layers and packaged in a 1012-pad organic land grid array using C4 (flip chip) assembly technology. A core speed back-side bus connects the processor to a 4-MB L3 cache. (6 refs).

  4. A rapid lateral flow immunoassay for the detection of tyrosine phosphatase-like protein IA-2 autoantibodies in human serum.

    Directory of Open Access Journals (Sweden)

    Ingrid Kikkas

    Full Text Available Type 1 diabetes (T1D results from the destruction of pancreatic insulin-producing beta cells and is strongly associated with the presence of islet autoantibodies. Autoantibodies to tyrosine phosphatase-like protein IA-2 (IA-2As are considered to be highly predictive markers of T1D. We developed a novel lateral flow immunoassay (LFIA based on a bridging format for the rapid detection of IA-2As in human serum samples. In this assay, one site of the IA-2As is bound to HA-tagged-IA-2, which is subsequently captured on the anti-HA-Tag antibody-coated test line on the strip. The other site of the IA-2As is bound to biotinylated IA-2, allowing the complex to be visualized using colloidal gold nanoparticle-conjugated streptavidin. For this study, 35 serum samples from T1D patients and 44 control sera from non-diabetic individuals were analyzed with our novel assay and the results were correlated with two IA-2A ELISAs. Among the 35 serum samples from T1D patients, the IA-2A LFIA, the in-house IA-2A ELISA and the commercial IA-2A ELISA identified as positive 21, 29 and 30 IA-2A-positive sera, respectively. The major advantages of the IA-2A LFIA are its rapidity and simplicity.

  5. A rapid lateral flow immunoassay for the detection of tyrosine phosphatase-like protein IA-2 autoantibodies in human serum.

    Science.gov (United States)

    Kikkas, Ingrid; Mallone, Roberto; Larger, Etienne; Volland, Hervé; Morel, Nathalie

    2014-01-01

    Type 1 diabetes (T1D) results from the destruction of pancreatic insulin-producing beta cells and is strongly associated with the presence of islet autoantibodies. Autoantibodies to tyrosine phosphatase-like protein IA-2 (IA-2As) are considered to be highly predictive markers of T1D. We developed a novel lateral flow immunoassay (LFIA) based on a bridging format for the rapid detection of IA-2As in human serum samples. In this assay, one site of the IA-2As is bound to HA-tagged-IA-2, which is subsequently captured on the anti-HA-Tag antibody-coated test line on the strip. The other site of the IA-2As is bound to biotinylated IA-2, allowing the complex to be visualized using colloidal gold nanoparticle-conjugated streptavidin. For this study, 35 serum samples from T1D patients and 44 control sera from non-diabetic individuals were analyzed with our novel assay and the results were correlated with two IA-2A ELISAs. Among the 35 serum samples from T1D patients, the IA-2A LFIA, the in-house IA-2A ELISA and the commercial IA-2A ELISA identified as positive 21, 29 and 30 IA-2A-positive sera, respectively. The major advantages of the IA-2A LFIA are its rapidity and simplicity.

  6. Disruption of gene expression rhythms in mice lacking secretory vesicle proteins IA-2 and IA-2β.

    Science.gov (United States)

    Punia, Sohan; Rumery, Kyle K; Yu, Elizabeth A; Lambert, Christopher M; Notkins, Abner L; Weaver, David R

    2012-09-15

    Insulinoma-associated protein (IA)-2 and IA-2β are transmembrane proteins involved in neurotransmitter secretion. Mice with targeted disruption of both IA-2 and IA-2β (double-knockout, or DKO mice) have numerous endocrine and physiological disruptions, including disruption of circadian and diurnal rhythms. In the present study, we have assessed the impact of disruption of IA-2 and IA-2β on molecular rhythms in the brain and peripheral oscillators. We used in situ hybridization to assess molecular rhythms in the hypothalamic suprachiasmatic nuclei (SCN) of wild-type (WT) and DKO mice. The results indicate significant disruption of molecular rhythmicity in the SCN, which serves as the central pacemaker regulating circadian behavior. We also used quantitative PCR to assess gene expression rhythms in peripheral tissues of DKO, single-knockout, and WT mice. The results indicate significant attenuation of gene expression rhythms in several peripheral tissues of DKO mice but not in either single knockout. To distinguish whether this reduction in rhythmicity reflects defective oscillatory function in peripheral tissues or lack of entrainment of peripheral tissues, animals were injected with dexamethasone daily for 15 days, and then molecular rhythms were assessed throughout the day after discontinuation of injections. Dexamethasone injections improved gene expression rhythms in liver and heart of DKO mice. These results are consistent with the hypothesis that peripheral tissues of DKO mice have a functioning circadian clockwork, but rhythmicity is greatly reduced in the absence of robust, rhythmic physiological signals originating from the SCN. Thus, IA-2 and IA-2β play an important role in the regulation of circadian rhythms, likely through their participation in neurochemical communication among SCN neurons.

  7. Apparent cosmic acceleration from Type Ia supernovae

    Science.gov (United States)

    Dam, Lawrence H.; Heinesen, Asta; Wiltshire, David L.

    2017-11-01

    Parameters that quantify the acceleration of cosmic expansion are conventionally determined within the standard Friedmann-Lemaître-Robertson-Walker (FLRW) model, which fixes spatial curvature to be homogeneous. Generic averages of Einstein's equations in inhomogeneous cosmology lead to models with non-rigidly evolving average spatial curvature, and different parametrizations of apparent cosmic acceleration. The timescape cosmology is a viable example of such a model without dark energy. Using the largest available supernova data set, the JLA catalogue, we find that the timescape model fits the luminosity distance-redshift data with a likelihood that is statistically indistinguishable from the standard spatially flat Λ cold dark matter cosmology by Bayesian comparison. In the timescape case cosmic acceleration is non-zero but has a marginal amplitude, with best-fitting apparent deceleration parameter, q_{0}=-0.043^{+0.004}_{-0.000}. Systematic issues regarding standardization of supernova light curves are analysed. Cuts of data at the statistical homogeneity scale affect light-curve parameter fits independent of cosmology. A cosmological model dependence of empirical changes to the mean colour parameter is also found. Irrespective of which model ultimately fits better, we argue that as a competitive model with a non-FLRW expansion history, the timescape model may prove a useful diagnostic tool for disentangling selection effects and astrophysical systematics from the underlying expansion history.

  8. Type IA topoisomerase inhibition by clamp closure.

    Science.gov (United States)

    Leelaram, Majety Naga; Bhat, Anuradha Gopal; Godbole, Adwait Anand; Bhat, Rajeshwari Subray; Manjunath, Ramanathapuram; Nagaraja, Valakunja

    2013-08-01

    Bacterial DNA topoisomerase I (topoI) catalyzes relaxation of negatively supercoiled DNA. The enzyme alters DNA topology through protein-operated DNA gate, switching between open and closed conformations during its reaction. We describe the mechanism of inhibition of Mycobacterium smegmatis and Mycobacterium tuberculosis topoI by monoclonal antibodies (mAbs) that bind with high affinity and inhibit at 10-50 nM concentration. Unlike other inhibitors of topoisomerases, the mAbs inhibited several steps of relaxation reaction, namely DNA binding, cleavage, strand passage, and enzyme-DNA dissociation. The enhanced religation of the cleaved DNA in presence of the mAb indicated closing of the enzyme DNA gate. The formation of enzyme-DNA heterocatenane in the presence of the mAbs as a result of closing the gate could be inferred by the salt resistance of the complex, visualized by atomic force microscopy and confirmed by fluorescence measurements. Locking the enzyme-DNA complex as a closed clamp restricted the movements of the DNA gate, affecting all of the major steps of the relaxation reaction. Enzyme trapped on DNA in closed clamp conformation formed roadblock for the elongating DNA polymerase. The unusual multistep inhibition of mycobacterial topoisomerases may facilitate lead molecule development, and the mAbs would also serve as valuable tools to probe the enzyme mechanism.

  9. IAS 12 needs methodical approach

    NARCIS (Netherlands)

    Hafkenscheid, R.P.F.M.; Janssen, C.M.L.

    2009-01-01

    The article describes a methodology used to establish the expected value of uncertain tax positions. The Project Update on Income Taxes released by the International Accounting Standards Board (IASB) in September 2008 aims to reduce the differences between IAS 12 Income Taxes and the SFAS 109

  10. Renal endoplasmic reticulum stress is coupled to impaired autophagy in a mouse model of GSD Ia.

    Science.gov (United States)

    Farah, Benjamin L; Landau, Dustin J; Wu, Yajun; Sinha, Rohit A; Loh, Alwin; Bay, Boon-Huat; Koeberl, Dwight D; Yen, Paul M

    2017-11-01

    GSD Ia (von Gierke Disease, Glycogen Storage Disease Type Ia) is a devastating genetic disorder with long-term sequelae, such as non-alcoholic fatty liver disease and renal failure. Down-regulated autophagy is involved in the development of hepatic metabolic dysfunction in GSD Ia; however, the role of autophagy in the renal pathology is unknown. Here we show that autophagy is impaired and endoplasmic reticulum (ER) stress is increased in the kidneys of a mouse model of GSD Ia. Induction of autophagy by rapamycin also reduces this ER stress. Taken together, these results show an additional role for autophagy down-regulation in the pathogenesis of GSD Ia, and provide further justification for the use of autophagy modulators in GSD Ia. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Spectroscopic Variability of Supergiant Star HD14134, B3Ia

    Indian Academy of Sciences (India)

    Y. M. Maharramov

    2017-06-19

    Jun 19, 2017 ... Orion, Astrophys. J., 150, 535. Pasok, A., Kolka, I. 1992, The Hα profile variations in the spectrum of HD225094, B3Ia, IBVS, 3804. Prinja R. K. et al. 1996, Variability in the optical wind lines of HD151804 (O9Iaf), Astron. Astrophys., 311,. 264. Rosendhal, J. D. 1973, A survey of Hα emission in early-type.

  12. The 'grey' assessment practice of IA screening

    DEFF Research Database (Denmark)

    Bidstrup, Morten

    2017-01-01

    practice, which influences the outcomes of formal screening procedures through consideration of impacts on neighbours and spatial zones of protection. Grey IA is to some extent motivated by the opportunity to save the resources required for full-scale IA, but an additional ‘green’ rationale also exists......Research focusing on the practices surrounding screening in Impact Assessment (IA) is limited. Yet, it has been found that development proposals sometimes are adjusted through an informal dialog with IA practitioners prior to or during screening. Such practice is often referred to as ‘grey IA....... Grey IA may influence the effectiveness of IA systems, but further research is needed before any conclusions can be made....

  13. 75 FR 16067 - Designation for the Champaign, IL; Emmett, MI; Davenport, IA; Enid, OK; Keokuk, IA; Marshall, MI...

    Science.gov (United States)

    2010-03-31

    ... the Champaign, IL; Emmett, MI; Davenport, IA; Enid, OK; Keokuk, IA; Marshall, MI; and Omaha, NE Areas... Iowa Davenport, IA (563-322-7149). 4/1/2010 3/31/2013 Additional Locations: Dubuque, IA; Muscatine, IA...: Catoosa, OK. Keokuk Keokuk, IA (319-524-6482). 4/1/2010 3/31/2013 Additional Location: Havana, IL...

  14. Gonorréia Gonorrhea

    Directory of Open Access Journals (Sweden)

    Gerson Oliveira Penna

    2000-10-01

    Full Text Available A gonorréia é uma infecção bacteriana freqüente, causada pela Neisseria gonorrhoeae, um diplococo Gram-negativo de transmissão quase que exclusiva através de contato sexual ou perinatal. Primariamente afeta membranas mucosas do trato genital inferior, e mais raramente, as mucosas do reto, orofaringe e conjuntiva. A infecção genital ascendente na mulher leva a uma complicação séria, a salpingite aguda, uma das principais causas de infertilidade feminina. A partir dos anos 90, deu-se início a um novo tempo no que se refere a descobertas sobre a patogenia da gonorréia e seu agente etiológico. O controle da gonorréia tem sido difícil na maioria das populações, e essa permanece um exemplo da influência que os fatores sociais, comportamentais e demográficos exercem na epidemiologia de uma doença infecciosa. O manejo da gonorréia e de outras doenças sexualmente transmissíveis requer tanto o tratamento do paciente e de seu parceiro sexual como medidas de saúde pública para interromper a transmissão da infecção e evitar complicações a longo prazo.Gonorrhea is a common bacterial infection caused by Neisseria gonorrhoeae, a Gram-negative diplococcus that is transmitted almost exclusively by sexual contact or perinatally. It primarily affects the mucous membranes of the lower genital tract and less frequently those of the rectum, oropharynx, and conjunctivae. Ascending genital infection in women leads to the predominant complication, acute salpingitis, one of the most common causes of female infertility in the world. Since the 1990s, a remarkable surge of information ensued regarding the pathogenesis of gonorrhea and its agent. Gonorrohea has proven difficult to control in most populations and remains a prime example of the influence that social, behavioral, and demographic factors can have on the epidemiology of an infectious disease. The management of gonorrhea and other sexually transmitted infections requires both

  15. Ia diastolic dysfunction: an echocardiographic grade.

    Science.gov (United States)

    Pandit, Anil; Mookadam, Farouk; Hakim, Fayaz A; Mulroy, Eoin; Saadiq, Rayya; Doherty, Mairead; Cha, Stephen; Seward, James; Wilansky, Susan

    2015-01-01

    To demonstrate that a distinct group of patients with Grade Ia diastolic dysfunction who do not conform to present ASE/ESE diastolic grading exists. Echocardiographic and demographic data of the Grade Ia diastolic dysfunction were extracted and compared with that of Grades I and II in 515 patients. The mean of age of the cohort was 75 ± 9 years and body mass index did not differ significantly between the 3 groups (P = 0.45). Measurements of left atrial volume index (28.58 ± 7 mL/m(2) in I, 33 ± 10 mL/m(2) in Ia, and 39 ± 12 mL/m(2) in II P Ia, and 79 ± 15 msec in II P Ia, and 217 ± 57 msec in II P Ia, and 22 ± 8 in II), and lateral E/e' (8 ± 3 in I, 15 ± 6 in Ia, and 18 ± 9 in II P Ia compared with I and II. These findings remained significant even after adjusting for age, gender, diabetes, and smoking. Patients with echocardiographic characteristics of relaxation abnormality (E/A ratio of Ia group. © 2014, Wiley Periodicals, Inc.

  16. Instrument ampersand controls section (IA) improvements

    International Nuclear Information System (INIS)

    Kramer, C.; Paul, J.

    1993-01-01

    This portion of the panel session briefly delineates improvements in the Instrument and Controls (IA) Section over the past few years. These improvements are listed briefly in summary form. The status of publication of the IA Section of AG-1 is reviewed

  17. Disturbances in the secretion of neurotransmitters in IA-2/IA-2beta null mice: changes in behavior, learning and lifespan.

    Science.gov (United States)

    Nishimura, T; Kubosaki, A; Ito, Y; Notkins, A L

    2009-03-17

    Islet-associated protein 2 (IA-2) and IA-2beta are major autoantigens in type 1 diabetes and transmembrane proteins in dense core secretory vesicles (DCV) of neuroendocrine cells. The deletion of these genes results in a decrease in insulin secretion. The present study was initiated to test the hypothesis that this deletion not only affects the secretion of insulin, but has a more global effect on neuroendocrine secretion that leads to disturbances in behavior and learning. Measurement of neurotransmitters showed that norepinephrine, dopamine and 5-HT were significantly decreased in the brain of double knockout (DKO) mice (Plearning, the DKO mice showed a highly significant increase in anxiety-like behavior (Plearning (Pfractionation studies revealed that IA-2beta, but not IA-2, co-purifies with fractions rich in synaptic vesicles (SV), and that the secretion of dopamine, GABA and glutamate from the synaptosomes of the DKO mice was significantly decreased as was the number of SV (Plearning disturbances, seizures and reduced lifespan.

  18. A selection fit mechanism in BMP receptor IA as a possible source for BMP ligand-receptor promiscuity.

    Directory of Open Access Journals (Sweden)

    Stefan Harth

    Full Text Available BACKGROUND: Members of the TGF-β superfamily are characterized by a highly promiscuous ligand-receptor interaction as is readily apparent from the numeral discrepancy of only seven type I and five type II receptors available for more than 40 ligands. Structural and functional studies have been used to address the question of how specific signals can be deduced from a limited number of receptor combinations and to unravel the molecular mechanisms underlying the protein-protein recognition that allow such limited specificity. PRINCIPAL FINDINGS: In this study we have investigated how an antigen binding antibody fragment (Fab raised against the extracellular domain of the BMP receptor type IA (BMPR-IA recognizes the receptor's BMP-2 binding epitope and thereby neutralizes BMP-2 receptor activation. The crystal structure of the complex of the BMPR-IA ectodomain bound to the Fab AbD1556 revealed that the contact surface of BMPR-IA overlaps extensively with the contact surface for BMP-2 interaction. Although the structural epitopes of BMPR-IA to both binding partners coincides, the structures of BMPR-IA in the two complexes differ significantly. In contrast to the structural differences, alanine-scanning mutagenesis of BMPR-IA showed that the functional determinants for binding to the antibody and BMP-2 are almost identical. CONCLUSIONS: Comparing the structures of BMPR-IA bound to BMP-2 or bound to the Fab AbD1556 with the structure of unbound BMPR-IA shows that binding of BMPR-IA to its interaction partners follows a selection fit mechanism, possibly indicating that the ligand promiscuity of BMPR-IA is inherently encoded by structural adaptability. The functional and structural analysis of the BMPR-IA binding antibody AbD1556 mimicking the BMP-2 binding epitope may thus pave the way for the design of low-molecular weight synthetic receptor binders/inhibitors.

  19. Hyperinducibility of Ia antigen on astrocytes correlates with strain-specific susceptibility to experimental autoimmune encephalomyelitis

    International Nuclear Information System (INIS)

    Massa, P.T.; ter Meulen, V.; Fontana, A.

    1987-01-01

    In search of a phenotypic marker determining genetically controlled susceptibility to delayed-type hypersensitivity (DTH) reactions in the brain-in particular, experimental autoimmune encephalomyelitis (EAE)- the authors have compared the γ-interferon (IFN-γ) induction of Ia molecules on astrocytes and macrophages from rat and mouse strains that are susceptible or resistant to this disease. They focused on Ia expression because DTH reactions to self or foreign antigens are largely mediated by lymphocytes restricted by class II (Ia) antigens of the major histocompatibility complex (MHC). The data demonstrate that Lewis (fully susceptible) and Brown Norway (BN) (fully resistant) rats are very different in that Lewis astrocytes express much higher levels of Ia than BN astrocytes. Similar data were obtained from an analysis of EAE-susceptible and -resistant mouse strains (SJL and BALB/c, respectively), which suggest that this phenomenon may be universal and not limited to only one mammalian species. At least one gene responsible for Ia hyperinduction is located outside the rat RT-1 or the mouse MHC locus. Animals congenic at the RT-1 or MHC locus of the resistant strain but with background genes of the susceptible strain exhibit intermediate levels of Ia compared to fully resistant and susceptible rodents, which fits well with the reduced EAE susceptibility of these congenic animals. Furthermore, hyperinduction of Ia is astrocyte specific, since peritoneal macrophages of susceptible and resistant strains exhibit identical profiles of Ia induction. Thus, astrocyte Ia hyperinducibility may be a major strain- and tissue-specific factor that contributes to Ia-restricted DTH reactions in the brain

  20. Testing the single degenerate channel for supernova Ia

    Science.gov (United States)

    Parsons, Steven

    2014-10-01

    The progenitors of supernova Ia are close binaries containing white dwarfs. Of crucial importance to the evolution of these systems is how much material the white dwarf can stably accrete and hence grow in mass. This occurs during a short-lived intense phase of mass transfer known as the super soft source (SSS) phase. The short duration of this phase and large extinction to soft X-rays means that only a handful are known in our Galaxy. Far more can be learned from the underlying SSS progenitor population of close white dwarf plus FGK type binaries. Unfortunately, these systems are hard to find since the main-sequence stars completely outshine the white dwarfs at optical wavelengths. Because of this, there are currently no known close white dwarf binaries with F, G or early K type companions, making it impossible to determine the contribution of the single degenerate channel towards supernova Ia. Using the GALEX and RAVE surveys we have now identified the first large sample of FGK stars with UV excesses, a fraction of which are these illusive, close systems. Following an intense ground based spectroscopic investigation of these systems, we have identified 5 definite close binaries, with periods of less than a few days. Here we apply for COS spectroscopic observations to measure the mass and temperature of the white dwarfs in order to determine the future evolution of these systems. This will provide a crucial test for the single degenerate channel towards supernova Ia.

  1. EnviroAtlas - Woodbine, IA - Block Groups

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is the base layer for the Woodbine, IA EnviroAtlas area. The block groups are from the US Census Bureau and are included/excluded based on...

  2. 76 FR 54521 - Iowa Disaster #IA-00036

    Science.gov (United States)

    2011-09-01

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12754 and 12755] Iowa Disaster IA-00036 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major [[Page 54522

  3. Greening America's Capitals - Des Moines, IA

    Science.gov (United States)

    Report from Greening America's Capitals project in Des Moines, IA, to help the city enhance the 6th Avenue Corridor with pedestrian and bike improvements and green infrastructure to manage stormwater.

  4. Direct and indirect regulation of spinal cord Ia afferent terminal formation by the γ-Protocadherins

    Directory of Open Access Journals (Sweden)

    Tuhina ePrasad

    2011-12-01

    Full Text Available The Pcdh-γ gene cluster encodes 22 protocadherin adhesion molecules that interact as homophilic multimers and critically regulate synaptogenesis and apoptosis of interneurons in the developing spinal cord. Unlike interneurons, the two primary components of the monosynaptic stretch reflex circuit, dorsal root ganglion sensory neurons and ventral motor neurons, do not undergo excessive apoptosis in Pcdh-γdel/del null mutants, which die shortly after birth. However, as we show here, mutants exhibit severely disorganized Ia proprioceptive afferent terminals in the ventral horn. In contrast to the fine net-like pattern observed in wild-type mice, central Ia terminals in Pcdh-γ mutants are expanded, clumped, and fill the space between individual motor neurons; quantitative analysis shows a ~2.5 fold increase in the area of terminals. Concomitant with this, there is a 70% loss of the collaterals that Ia afferents extend to ventral interneurons, many of which undergo apoptosis in the mutants. The Ia afferent phenotype is ameliorated, though not entirely rescued, when apoptosis is blocked in Pcdh-γ null mice by introduction of a Bax null allele. This indicates that loss of ventral interneurons, which act as intermediate Ia afferent targets, contributes to the disorganization of terminals on motor pools. Restricted mutation of the Pcdh-γ cluster using conditional mutants and multiple Cre transgenic lines (Wnt1-Cre for sensory neurons; Pax2-Cre for ventral interneurons; Hb9-Cre for motor neurons also revealed a direct requirement for the γ-Pcdhs in Ia neurons and ventral interneurons, but not in motor neurons themselves. Together, these genetic manipulations indicate that the γ-Pcdhs are required for the formation of the Ia afferent circuit in two ways: First, they control the survival of ventral interneurons that act as intermediate Ia targets; and second, they provide a homophilic molecular cue between Ia afferents and target ventral interneurons.

  5. Penerapan PSAK Adopsi IAS 41 Agriculture

    OpenAIRE

    Stefanus Ariyanto; Heri Sukendar; Heny Kurniawati

    2014-01-01

    This study aims to determine whether the application of PSAK adopted from IAS 41: Agriculture should be applied to State-Owned Enterprises, especially the plantation SOE. So that the SOE financial information produced becomes more useful for decision-making. Furthermore, this study wants to answer what benefits can be obtained from the implementation of this standard on the plantation-based SOE. The main characteristic of IAS is the use of fair value model for biological assets owned by the a...

  6. IAS 41 Agriculture: Fair Value Accounting

    Directory of Open Access Journals (Sweden)

    Viorel Lefter

    2007-05-01

    Full Text Available Issuing this standard that had to be applied for the first time for the financial statements started after 1.01.2003 meant a change of direction from two points of view: on one hand, through IAS 41 was issued for the first time an extensive standard typical for this sector and, on the other hand, for the first time were included in the income statement, independently from the sales transactions, incomes from variations of the fair value of an asset. Because of this last aspect, IAS 41 can be considered an important standard, because it represents the starting point of a consistent transition from the purchase cost principle towards a fair value accounting. IASC has dedicated to the thematic field of agriculture a specific standard, because this economic branch has a great importance for the developing countries. On the other hand, IAS 41 is also applied for the agricultural activities of the enterprises from other sectors.

  7. Cloud Infrastructure & Applications - CloudIA

    Science.gov (United States)

    Sulistio, Anthony; Reich, Christoph; Doelitzscher, Frank

    The idea behind Cloud Computing is to deliver Infrastructure-as-a-Services and Software-as-a-Service over the Internet on an easy pay-per-use business model. To harness the potentials of Cloud Computing for e-Learning and research purposes, and to small- and medium-sized enterprises, the Hochschule Furtwangen University establishes a new project, called Cloud Infrastructure & Applications (CloudIA). The CloudIA project is a market-oriented cloud infrastructure that leverages different virtualization technologies, by supporting Service-Level Agreements for various service offerings. This paper describes the CloudIA project in details and mentions our early experiences in building a private cloud using an existing infrastructure.

  8. Low mass SN Ia and the late light curve

    International Nuclear Information System (INIS)

    Colgate, S.A.; Fryer, C.L.

    1995-01-01

    The late bolometric light curves of type Ia supernovae, when measured accurately over several years, show an exponential decay with a 56d half-life over a drop in luminosity of 8 magnitudes (10 half-lives). The late-time light curve is thought to be governed by the decay of Co 56 , whose 77d half-life must then be modified to account for the observed decay time. Two mechanisms, both relying upon the positron fraction of the Co 56 decay, have been proposed to explain this modification. One explanation requires a large amount of emission at infra-red wavelengths where it would not be detected. The other explanation has proposed a progressive transparency or leakage of the high energy positrons (Colgate, Petschek and Kriese, 1980). For the positrons to leak out of the expanding nebula at the required rate necessary to produce the modified 56d exponential, the mass of the ejecta from a one foe (10 51 erg in kinetic energy) explosion must be small, M ejec = 0.4M circle-dot with M ejec ∝ KE 0.5 . Thus, in this leakage explanation, any reasonable estimate of the total energy of the explosion requires that the ejected mass be very much less than the Chandrasekhar mass of 1.4M circle-dot . This is very difficult to explain with the ''canonical'' Chandrasekhar-mass thermonuclear explosion that disintegrates the original white dwarf star. This result leads us to pursue alternate mechanisms of type Ia supernovae. These mechanisms include sub-Chandrasekhar thermonuclear explosions and the accretion induced collapse of Chandrasekhar mass white dwarfs. We will summarize the advantages and disadvantages of both mechanisms with considerable detail spent on our new accretion induced collapse simulations. These mechanisms lead to lower Ni 56 production and hence result in type Ia supernovae with luminosities decreased down to ∼ 50% that predicted by the ''standard'' model

  9. 76 FR 27738 - Iowa Disaster #IA-00030

    Science.gov (United States)

    2011-05-12

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12541 and 12542] Iowa Disaster IA-00030 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the State of Iowa dated 05/04/2011. Incident: Severe storms and tornadoes...

  10. 75 FR 45681 - Iowa Disaster #IA-00025

    Science.gov (United States)

    2010-08-03

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12252 and 12253] Iowa Disaster IA-00025 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA-1928- DR), dated 07/27...

  11. 78 FR 28939 - Iowa Disaster #IA-00050

    Science.gov (United States)

    2013-05-16

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13567 and 13568] Iowa Disaster IA-00050 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA-4114- DR), dated 05/06...

  12. 76 FR 66768 - Iowa Disaster #IA-00033

    Science.gov (United States)

    2011-10-27

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12895 and 12896] Iowa Disaster IA-00033 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for the State of Iowa (FEMA-1998-DR), dated 10/18/2011. Incident: Flooding...

  13. 78 FR 36010 - Iowa Disaster #IA-00052

    Science.gov (United States)

    2013-06-14

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13605 and 13606] Iowa Disaster IA-00052 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA-4119- DR), dated 05/31...

  14. 78 FR 48762 - Iowa Disaster #IA-00053

    Science.gov (United States)

    2013-08-09

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13699 and 13700] Iowa Disaster IA-00053 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA-4135- DR), dated 07/31...

  15. 75 FR 47035 - Iowa Disaster # IA-00026

    Science.gov (United States)

    2010-08-04

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12258 and 12259] Iowa Disaster IA-00026 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance only for the State of Iowa (FEMA-1930- DR), dated 07/29...

  16. 76 FR 29284 - Iowa Disaster #IA-00031

    Science.gov (United States)

    2011-05-20

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12568 and 12569] Iowa Disaster IA-00031 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA-1977- DR), dated 05/05...

  17. 76 FR 55721 - Iowa Disaster #IA-00038

    Science.gov (United States)

    2011-09-08

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12772 and 12773] Iowa Disaster IA-00038 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA-4018- DR), dated 08/30...

  18. 76 FR 54522 - Iowa Disaster #IA-00037

    Science.gov (United States)

    2011-09-01

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12760 and 12761] Iowa Disaster IA-00037 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA-4016- DR), dated 08/24...

  19. 75 FR 10329 - Iowa Disaster #IA-00022

    Science.gov (United States)

    2010-03-05

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12053 and 12054] Iowa Disaster IA-00022 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the State of IOWA (FEMA--1877-- DR), dated 02...

  20. 75 FR 53006 - Iowa Disaster #IA-00026

    Science.gov (United States)

    2010-08-30

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12258 and 12259] Iowa Disaster IA-00026 AGENCY: U.S. Small Business Administration. ACTION: Amendment 2. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA- 1930-DR...

  1. 75 FR 51507 - Iowa Disaster #IA-00024

    Science.gov (United States)

    2010-08-20

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12279 and 12280] Iowa Disaster IA-00024 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for the State of Iowa (FEMA-1930-DR), dated 08/14/2010. Incident: Severe...

  2. 78 FR 42147 - Iowa Disaster #IA-00054

    Science.gov (United States)

    2013-07-15

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13645 and 13646] Iowa Disaster IA-00054 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance only for the State of Iowa (FEMA-4126- DR), dated 07/02...

  3. 76 FR 52042 - Iowa Disaster #IA-00035

    Science.gov (United States)

    2011-08-19

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12734 and 12735] Iowa Disaster IA-00035 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the State of Iowa Dated. Incident: Severe Storms and Flash Flooding. Incident...

  4. 75 FR 11582 - IOWA Disaster # IA-00023

    Science.gov (United States)

    2010-03-11

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12062 and 12063] IOWA Disaster IA-00023 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA-1880- DR), dated 03/02...

  5. Penerapan PSAK Adopsi IAS 41 Agriculture

    Directory of Open Access Journals (Sweden)

    Stefanus Ariyanto

    2014-05-01

    Full Text Available This study aims to determine whether the application of PSAK adopted from IAS 41: Agriculture should be applied to State-Owned Enterprises, especially the plantation SOE. So that the SOE financial information produced becomes more useful for decision-making. Furthermore, this study wants to answer what benefits can be obtained from the implementation of this standard on the plantation-based SOE. The main characteristic of IAS is the use of fair value model for biological assets owned by the agriculture-based entity. The use of this model raises a lot of controversy, primarily, associated with relevant quality and reliability of the information it produces. Research used qualitative method with data collection through literature study, survey, interview, and observation. Survey and interview were divided into two major parts, which were: on the compilers of financial statements and the stakeholders. From this study it can be concluded that the PSAK based on IAS 41 have not to be implemented yet in the near future due to IAS 41 will undergo quite significant revision. Currently, the State-Owned Enterprises could use the PSAK plantation SOE that has been issued.

  6. Modelo biopsicossocial e formulação comportamental: compreendendo a cefaléia do tipo tensional Modelo biopsicosocial y formulación comportamental: comprendiendo la cefalea del tipo tensional The bio-psychosocial model and behavioral formulation: understanding the tension-type headache

    Directory of Open Access Journals (Sweden)

    Adriana Mayon Neiva Flores

    2008-03-01

    Full Text Available A cefaléia do tipo tensional constitui um tipo freqüente de dor de cabeça, que tende a ocasionar uma série de comportamentos de evitação, com prejuízos físicos, sociais e psicológicos aos indivíduos afetados. O presente trabalho descreve algumas contribuições do modelo biopsicossocial de saúde para a compreensão da cefaléia do tipo tensional, descreve os tratamentos mais freqüentemente oferecidos e discute as vantagens de modalidades terapêuticas que utilizam a formulação comportamental. Destaca-se a relevância da consideração de fatores psicossociais presentes nas formas mais comuns de evolução da cefaléia do tipo tensional, o que contribui para a elaboração de planos de tratamento mais eficientes e coerentes com uma proposta realmente sistêmica e idiográfica.La cefalea del tipo tensional constituye un tipo frecuente de dolor de cabeza, que tiene la tendencia a ocasionar una serie de comportamientos de evitación, con daños físicos, sociales y psicológicos a los individuos afectados. El presente trabajo describe algunas contribuciones del modelo biopsicosocial de salud para la comprensión de la cefalea del tipo tensional, describe los tratamientos más frecuentemente ofrecidos y discute las ventajas de modalidades terapéuticas que utilizan la formulación comportamental. Se destaca la relevancia de la consideración de factores psicosociales presentes en las formas más comunes de evolución de la cefalea del tipo tensional, lo que contribuye para la elaboración de planes de tratamiento más eficientes y coherentes con una propuesta realmente sistémica e idiográfica.Tension-type headache are a frequent source of complaints in health assistance units. It tends to cause avoidance behaviors with adverse consequences in physical, psychological and social aspects. Contributions from the Bio-Psychosocial perspective are described for a better understanding of the tension-type headache problem. Study also analyzes

  7. 77 FR 42427 - Amendment of Class E Airspace; Grinnell, IA

    Science.gov (United States)

    2012-07-19

    ...-1430; Airspace Docket No. 11-ACE-23] Amendment of Class E Airspace; Grinnell, IA AGENCY: Federal... Class E airspace at Grinnell Regional Airport, Grinnell, IA, by removing reference to the Grinnell NDB... Regional Airport, Grinnell, IA, and amends the geographic coordinates of the airport to coincide with the...

  8. 78 FR 18800 - Amendment of Class E Airspace; Decorah, IA

    Science.gov (United States)

    2013-03-28

    ...-1433; Airspace Docket No. 11-ACE-26] Amendment of Class E Airspace; Decorah, IA AGENCY: Federal... Decorah, IA. Decommissioning of the Decorah non-directional beacon (NDB) at Decorah Municipal Airport has... Register a notice of proposed rulemaking (NPRM) to amend Class E airspace for the Decorah, IA, area...

  9. 77 FR 68682 - Amendment of Class E Airspace; Guthrie, IA

    Science.gov (United States)

    2012-11-16

    ...-1436; Airspace Docket No. 11-ACE-29] Amendment of Class E Airspace; Guthrie, IA AGENCY: Federal... Guthrie, IA. Decommissioning of the Guthrie Center non-directional radio beacon (NDB) at Guthrie County... proposed rulemaking (NPRM) to amend Class E airspace for the Guthrie, IA, area, creating additional...

  10. 77 FR 66067 - Amendment of Class E Airspace; Boone, IA

    Science.gov (United States)

    2012-11-01

    ...-1432; Airspace Docket No. 11-ACE-25] Amendment of Class E Airspace; Boone, IA AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action amends Class E airspace at Boone, IA... proposed rulemaking (NPRM) to amend Class E airspace for the Boone, IA, area, creating additional...

  11. 77 FR 4459 - Amendment of Class E Airspace; Greenfield, IA

    Science.gov (United States)

    2012-01-30

    ...-0846; Airspace Docket No. 11-ACE-18] Amendment of Class E Airspace; Greenfield, IA AGENCY: Federal... Greenfield, IA. Decommissioning of the Greenfield non-directional beacon (NDB) at Greenfield Municipal... rulemaking to amend Class E airspace for Greenfield, IA, reconfiguring controlled airspace at Greenfield...

  12. 76 FR 75449 - Establishment of Class E Airspace; Stuart, IA

    Science.gov (United States)

    2011-12-02

    ...-0831; Airspace Docket No. 11-ACE-17] Establishment of Class E Airspace; Stuart, IA AGENCY: Federal... for Stuart, IA, to accommodate new COPTER area navigation (RNAV) Standard Instrument Approach... Federal Register a notice of proposed rulemaking to establish Class E airspace for Stuart, IA, creating...

  13. 75 FR 23580 - Amendment of Class E Airspace; Mapleton, IA

    Science.gov (United States)

    2010-05-04

    ...-1155; Airspace Docket No. 09-ACE-14] Amendment of Class E Airspace; Mapleton, IA AGENCY: Federal... Mapleton, IA, adding additional controlled airspace to accommodate Area Navigation (RNAV) Standard Instrument Approach Procedures (SIAPs) at James G. Whiting Memorial Field Airport, Mapleton, IA. The FAA is...

  14. 77 FR 66069 - Amendment of Class E Airspace; Perry, IA

    Science.gov (United States)

    2012-11-01

    ...-1435; Airspace Docket No. 11-ACE-28] Amendment of Class E Airspace; Perry, IA AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action amends Class E airspace at Perry, IA... proposed rulemaking (NPRM) to amend Class E airspace for the Perry, IA, area, creating additional...

  15. 75 FR 37292 - Amendment of Class E Airspace; Cherokee, IA

    Science.gov (United States)

    2010-06-29

    ...-0085; Airspace Docket No. 10-ACE-1] Amendment of Class E Airspace; Cherokee, IA AGENCY: Federal... Cherokee, IA. Decommissioning of the Pilot Rock non-directional beacon (NDB) at Cherokee County Regional Airport, Cherokee, IA has made this action necessary to enhance the safety and management of Instrument...

  16. 78 FR 76053 - Amendment of Class E Airspace; Chariton, IA

    Science.gov (United States)

    2013-12-16

    ...-0255; Airspace Docket No. 13-ACE-4] Amendment of Class E Airspace; Chariton, IA AGENCY: Federal... Chariton, IA. Decommissioning of the Chariton non-directional beacon (NDB) at Chariton Municipal Airport... Register a notice of proposed rulemaking (NPRM) to amend Class E airspace for the Chariton, IA, area...

  17. 76 FR 73501 - Amendment of Class E Airspace; Carroll, IA

    Science.gov (United States)

    2011-11-29

    ...-0845; Airspace Docket No. 11-ACE-19] Amendment of Class E Airspace; Carroll, IA AGENCY: Federal... Carroll, IA. Decommissioning of the Carroll non-directional beacon (NDB) at Arthur N. Neu Airport, Carroll, IA, has made this action necessary to enhance the safety and management of Instrument Flight Rule...

  18. 75 FR 23581 - Amendment of Class E Airspace; Emmetsburg, IA

    Science.gov (United States)

    2010-05-04

    ...-1153; Airspace Docket No. 09-ACE-13] Amendment of Class E Airspace; Emmetsburg, IA AGENCY: Federal... Emmetsburg, IA, adding additional controlled airspace to accommodate Area Navigation (RNAV) Standard Instrument Approach Procedures (SIAPs) at Emmetsburg Municipal Airport, Emmetsburg, IA. The FAA is taking...

  19. 76 FR 75447 - Amendment of Class E Airspace; Centerville, IA

    Science.gov (United States)

    2011-12-02

    ...-0830; Airspace Docket No. 11-ACE-16] Amendment of Class E Airspace; Centerville, IA AGENCY: Federal... Centerville, IA. Decommissioning of the Centerville non-directional beacon (NDB) and cancellation of the NDB... Federal Register a notice of proposed rulemaking to amend Class E airspace for the Centerville, IA, area...

  20. Targeted disruption of the IA-2beta gene causes glucose intolerance and impairs insulin secretion but does not prevent the development of diabetes in NOD mice.

    NARCIS (Netherlands)

    Kubosaki, A.; Gross, S.; Miura, J.; Saeki, K.; Zhu, M.; Nakamura, S.; Hendriks, W.J.A.J.; Notkins, A.L.

    2004-01-01

    Insulinoma-associated protein (IA)-2beta, also known as phogrin, is an enzymatically inactive member of the transmembrane protein tyrosine phosphatase family and is located in dense-core secretory vesicles. In patients with type 1 diabetes, autoantibodies to IA-2beta appear years before the

  1. La scelta della Fair Value Option nello IAS 40: evidenze empiriche sul settore Real Estate

    OpenAIRE

    Porta, Silvia

    2016-01-01

    The adoption of IAS/IFRS by the European Union has represented a key accounting change for European companies and offers a rich source of analysis to the scientific community. This thesis is part of the debate on-going on the choice between fair value and historical cost as the optimal evaluation criterium. The empirical research focuses on the accounting standard IAS 40, which is particularly suitable for this type of investigation as it is one of the few principles that allow the right to c...

  2. Supernovae Ia in 2017: a long time delay from merger/accretion to explosion

    Science.gov (United States)

    Soker, Noam

    2018-04-01

    I use recent observational and theoretical studies of type Ia supernovae (SNe Ia) to further constrain the viable SN Ia scenarios and to argue that there must be a substantial time delay between the end of the merger of the white dwarf (WD) with a companion or the end of mass accretion on to the WD and its terminal explosion. This merger/accretion to explosion delay (MED) is required to allow the binary system to lead to a more or less spherical explosion and to prevent a pre-explosion ionizing radiation. Considering these recent results and the required MED, I conclude that the core degenerate scenario is somewhat more favorable over the other scenarios, followed by the double degenerate scenario. Although the single degenerate scenario is viable as well, it is less likely to account for common (normal) SN Ia. As all scenarios require substantial MED, the MED has turned from a disadvantage of the core degenerate scenario to a challenge that theory should overcome. I hope that the requirement for a MED will stimulate the discussion of the different SN Ia scenarios and the comparison of the scenarios to each other.

  3. Tension between SNeIa and BAO: current status and future forecasts

    Energy Technology Data Exchange (ETDEWEB)

    Escamilla-Rivera, Celia [Astrophysics, University of Oxford, DWD, Kebble Road, Oxford, OX1 3RH (United Kingdom); Lazkoz, Ruth; Salzano, Vincenzo; Sendra, Irene, E-mail: celia_escamilla@ehu.es, E-mail: ruth.lazkoz@ehu.es, E-mail: vincenzo.salzano@ehu.es, E-mail: irene.sendra@ehu.es [Fisika Teorikoaren eta Zientziaren Historia Saila, Zientzia eta Teknologia Fakultatea, Euskal Herriko Unibertsitatea, 644 Posta Kutxatila, 48080 Bilbao (Spain)

    2011-09-01

    Using real and synthetic Type Ia SNe (SNeIa) and baryon acoustic oscillations (BAO) data representing current observations forecasts, this paper investigates the tension between those probes in the dark energy equation of state (EoS) reconstruction considering the well known CPL model and Wang's low correlation reformulation. In particular, here we present simulations of BAO data from both the the radial and transverse directions. We also explore the influence of priors on Ω{sub m} and Ω{sub b} on the tension issue, by considering 1σ deviations in either one or both of them. Our results indicate that for some priors there is no tension between a single dataset (either SNeIa or BAO) and their combination (SNeIa+BAO). Our criterion to discern the existence of tension (σ-distance) is also useful to establish which is the dataset with most constraining power; in this respect SNeIa and BAO data switch roles when current and future data are considered, as forecasts predict and spectacular quality improvement on BAO data. We also find that the results on the tension are blind to the way the CPL model is addressed: there is a perfect match between the original formulation and that by the correlation optimized proposed in Wang (2008), but the errors on the parameters are much narrower in all cases of our exhaustive exploration, thus serving the purpose of stressing the convenience of this reparametrization.

  4. Reference data for the Mark-Ia core of SNR-300

    International Nuclear Information System (INIS)

    Prescher, K.; Stanculescu, A.; de Wouters, R.

    1985-02-01

    The updated reference data of the Mark-Ia core of SNR-300 are documented in this report within the framework of the preparation of documents for the operational license. Data (volume fractions and number densities) for the different types of core assemblies are given for room temperature, maintenance temperature (200 deg C isothermal) and full-power

  5. Autoantibodies to GAD65 and IA-2 in canine diabetes mellitus.

    Science.gov (United States)

    Davison, L J; Weenink, S M; Christie, M R; Herrtage, M E; Catchpole, B

    2008-11-15

    Diabetes mellitus in dogs shares many characteristics with the human type 1 disease and virtually all diabetic dogs require insulin therapy to control hyperglycaemia. Insulin deficiency is suspected to result from immune-mediated destruction of pancreatic beta cells in some cases. Human patients suffering from Type 1A (immune-mediated) diabetes or latent autoimmune diabetes of the adult (LADA) demonstrate circulating autoantibodies against the 65kDa isoform of glutamic acid decarboxylase (GAD65) and/or insulinoma antigen-2 (IA-2). The aims of the current study were to develop radio-immunoassays to detect serum antibodies against recombinant canine GAD65 and IA-2 and to identify diabetic dogs showing serological evidence of autoreactivity to these pancreatic beta cell antigens. Canine GAD65 and the 3' end of IA-2 (coding for amino acids 771-979 of the intracellular domain) were amplified by PCR from cDNA prepared from canine insulinoma tissue and cloned into the pCRII vector. The canine sequences were later confirmed by identifying GAD2 and PTPRN genes from the dog genome assembly. Recombinant (35)S-methionine-radiolabelled canine GAD65 and IA-2 (771-979) proteins were used in radio-immunoprecipitation assays to screen sera from 30 newly diagnosed diabetic dogs and 30 control dogs. Four of 30 canine diabetic patients had significant GAD65 autoreactivity (pdogs were positive for autoantibodies to IA-2 (771-979). Two diabetic dogs showed dual autoantigen reactivity. These preliminary data indicate that serological reactivity to GAD65 and IA-2 is present in a proportion of diabetic dogs and suggests that, in some cases, canine diabetes is associated with an autoimmune response to these antigens.

  6. Not any type of rice performs equally to improve lactose-induced diarrhea characteristics in rats: is amylose an antidiarrheal factor? No tratamento das diarréias induzidas por lactose em ratos, nem todas as variedades de arroz agem da mesma forma: poderia ser a amilose um fator antidiarreico?

    Directory of Open Access Journals (Sweden)

    Ana Lia Felipoff

    2012-06-01

    Full Text Available The effectiveness of different types of rice in relation to their ability to accelerate diarrhea recovering was evaluated in a rat model of osmotic diarrhea (OD. Animals (90-100 g received protein free diet until reaching up to 20% weight loss, followed by lactose rich diet (LRD to induce osmotic diarrhea. Rats presenting osmotic diarrhea were divided into 4 groups, which received lactose rich diet for 4 days from 8 am to 8 pm, and one of three experimental products containing 6% rice flour differing in amylose content during the night: high (HA, intermediate (IA, and low (LA. A group fed stock diet containing equivalent amount of lactose was taken as control and allowed to recover spontaneously. Amylose and viscosity (cp at 25 °C, 10 rpm of final products were determined. Effectiveness was expressed as the ratio between percentages of normal vs. diarrheic stools during the treatment. Fecal characteristics in this rat model improved only as result of feeding high amylose content (HA type of rice. In this experimental model of osmotic diarrhea in young rats, the antidiarrheal effects of rice were strongly dependent on the type of diet used and appear to be related to its amylose content.Avaliou-se a eficiência de diferentes tipos de arroz quanto a sua habilidade de acelerar a recuperação de um episódio de diarreia em um modelo de indução de diarreia osmótica (DO em ratos. Animais (90-100 g receberam dieta isenta de proteína até perderem 20% do seu peso, seguida de uma dieta rica em lactose para indução de diarreia. Os ratos que apresentaram diarreia osmótica foram divididos em quatro grupos, os quais receberam uma dieta rica em lactose durante quatro dias das 8 às 20 hours e, durante a noite, receberam um dos produtos experimentais, com 6% de farinha de arroz e diferentes quantidades de amilose: alto (AA, intermediário (IA e baixo (BA teor de amilose. Um grupo alimentado com ração comercial foi escolhido como controle e para

  7. The Implementation of IAS 16 and IAS 41 at Andrew Peller Limited

    Science.gov (United States)

    Lapointe-Antunes, Pascale; Moore, James

    2013-01-01

    This case asks students to play the role of Doug Grodeckie, Manager of Financial Reporting at Andrew Peller Limited (APL). Doug was asked to prepare a report analyzing Andrew Peller Limited's current tangible long-lived assets disclosures and making recommendations on how best to comply with International Accounting Standard (IAS) 16 Property,…

  8. Classification of ASASSN-18dl as a type Ia supernova

    Science.gov (United States)

    Pessi, P.; Quirola, J.; Navarro, G.; Dennefeld, M.; Ferrero, L.; Sani, E.; Schmidtobreick, L.

    2018-02-01

    We report the classification of the supernova candidate ASASSN-18dl which was discovered as a V 17.6mag transient by the All Sky Automated Survey for SuperNovae (ASAS-SN, Shappee et al. 2014) on 2018-02-21.25 UT. The discovery is reported in ATel #11343 (Stone et al. 2018).

  9. Molecular analysis of glycogen storage disease type Ia in Iranian ...

    Indian Academy of Sciences (India)

    SHEKARI KHANIANI MAHMOUD1,2

    The gene encodes a hydrophobic pro- tein containing 357 amino acids and nine transmembrane domains ... terolamia, hypertriglyceridamia, hyperuricaemia and lactic acidamia (Janecke et al. 2001; Emino˘glu et al. .... Triglyceride serum uric acid values were higher in all the four patients, and they also suffered from severe ...

  10. Theoretical considerations about implementation of IAS 41 in Romania

    OpenAIRE

    Liliana FELEAGĂ; Niculae FELEAGĂ; Vasile RĂILEANU

    2012-01-01

    Although agriculture is an important part of the world economy, accounting in agriculture still has many shortcomings. The adoption of IAS 41 „Agricuture” has tried to improve this situation and increase the comparability of financial statements of entities in the agricultural sector. Although controversial, IAS 41 is the first step of a consistent transition to fair value assessment in the agricultural sector. The objective of our work is the analysis of IAS 41 and current accounting agricul...

  11. IAS 41 Implementation Challenges – The Case of Romania

    OpenAIRE

    Liliana Feleagă; Niculae Feleagă; Vasile Răileanu

    2012-01-01

    Although agriculture is an important part of the world economy, accounting in agriculture still has many shortcomings. The adoption of IAS 41 "Agriculture" has tried to improve this situation and increase the comparability of financial statements of entities in the agricultural sector. Although controversial, IAS 41 is the first step of a consistent transition to fair value assessment in the agricultural sector. The objective of our work is the analysis of IAS 41 and curr...

  12. THE GEOMORPHOSITES OF ROŞIA MONTANĂ

    Directory of Open Access Journals (Sweden)

    Maria-Adina Jurj

    2016-06-01

    Full Text Available The geomorphosites of Roșia Montană. The volcanic relief of the Roșia Montană mining area is characterised by a significant number of geomorphosites, represented especially by necks and dykes, such as: Cârnic, Orlea, Jig-Văidoaia, Lety etc. Another category of geomorphosites is represented by those with hydrographic features, namely the ponds created for mining purposes since Roman period. We identified a number of 14 geomorphosites; 9 of these are the results of the Neogene volcanic activity, and 5 are the ponds which appeared as an indirect consequence of the volcanic specific of the area. The geomorphosites created by the volcanic activity have also a significant archaeological, historical and cultural value, due to the valuable mining galleries and another evidences of this ancient activity. Among all the geomorphosites of the area, the most important one is Cârnic Massif which has a complex system of underground mining galleries, some of them belonging to Roman period. We consider that capitalization through touristic activities of these landforms is the best utilization in terms of ecological, cultural and economic perspectives.

  13. Does the histologic predominance of pathological stage IA lung adenocarcinoma influence the extent of resection?

    Science.gov (United States)

    Ito, Hiroyuki; Nakayama, Haruhiko; Murakami, Shuji; Yokose, Tomoyuki; Katayama, Kayoko; Miyata, Yoshihiro; Okada, Morihito

    2017-09-01

    We studied whether histologic subtype according to the new IASLC/ATS/ERS adenocarcinoma classification influences the extent of resection in patients with pathological stage IA lung adenocarcinoma. Data on 288 patients with pathological stage IA lung adenocarcinoma were analyzed retrospectively. Recurrence-free survival (RFS) rates were compared according to clinicopathological characteristics, including predominant histologic subtype and extent of resection. Median follow-up was 38.9 months. Lobectomy was performed in 146 patients, and sublobar resection in 142 patients. When recurrence was compared among the low-grade group (adenocarcinoma in situ, AIS; minimally invasive adenocarcinoma, MIA), intermediate-grade group (lepidic, acinar, and papillary) and high-grade group (solid and micropapillary), the RFS rate decreased as the grade increased (p = 0.037). There was no recurrence in the low-grade or lepidic predominant groups. The recurrence pattern did not differ according to the type of resection or histological subtype. Even in the intermediate- and high-grade groups, the extent of resection was not significantly related to the RFS rate (p = 0.622, p = 0.516). The results were unchanged after adjusting for independent risk factors. The concordance rate between clinical and pathological stage IA was good in low (98.6%) and intermediate grade (84.6%) and poor in high grade (41.2%). AIS, MIA, and lepidic predominant may be curable by any type of complete resection. Even in invasive subtypes, lobectomy does not offer a recurrence-free advantage over sublobar resection. However, in the high-grade group, less than half of clinical stage IA was actually pathological stage IA. Physicians should exercise caution whenever sublobar resection is planned.

  14. 3IA Conference (3IA’2011)

    CERN Document Server

    Miaoulis, Georgios; Intelligent Computer Graphics 2011

    2012-01-01

    In Computer Graphics, the use of intelligent techniques started more recently than in other research areas. However, during these last two decades, the use of intelligent Computer Graphics techniques is growing up year after year and more and more interesting techniques are presented in this area.   The purpose of this volume is to present current work of the Intelligent Computer Graphics community, a community growing up year after year. This volume is a kind of continuation of the previously published Springer volumes “Artificial Intelligence Techniques for Computer Graphics” (2008), “Intelligent Computer Graphics 2009” (2009) and “Intelligent Computer Graphics 2010” (2010).   This volume contains selected extended papers from the last 3IA Conference (3IA’2011), which has been held in Athens (Greece) in May 2011. This year papers are particularly exciting and concern areas like virtual reality, artificial life, data visualization, games, global illumination, point cloud modelling, declarativ...

  15. Anastilosis Virtual de Felipéia

    Directory of Open Access Journals (Sweden)

    Hélio Costa Lima

    2011-04-01

    Full Text Available This text is about a virtual anastylosis of Felipéia, capital of Paraíba, the first city founded in Brazil under the Spanish Crown in 1585, during the Iberic Union. Recently, infographics resources enabled the reconstruction, with great precision, of the old city’s ground plans from Dutch maps from 1634-37, and establish the first hypothesis of a tridimensional configuration of the city. Now, measuring and studies are being done to make possible a piece by piece virtual anastylosis of the buildings and, after that, a tridimensional virtual reconstruction of the historical city, which will enable virtual walkabouts on the streets, squares and buildings.

  16. Scholarship for Service: IA Tutorials and Workshops for Educators

    National Research Council Canada - National Science Library

    Irvine, Cynthia E; Falby, Naomi B

    2005-01-01

    ... of Information Assurance (IA) and computer security. The target audience of the workshops has been 2-year college, 4-year college, and university-level educators who have responsibility for teaching curricula that are, or could be, related to IA issues...

  17. The Connection between IAS/IFRS and Social Responsibility

    Directory of Open Access Journals (Sweden)

    Stefano AMELIO

    2016-05-01

    Full Text Available The aim of the paper is to evaluate the degree of social responsibility arising from the statement of comprehensive income prepared according to IAS/IFRS, to demonstrate whether the values obtained from prospects and from the calculation of the indicators are sufficient to analyze the Company's performance from the perspective of social responsibility and sustainable value or not. In order to achieve the objective of harmonization, the European Union adopted the IAS/IFRS developed by the International Accounting Standards Board (IASB. The research is divided into two sections and the approach used is mainly theoretical and qualitative. In the first part, the financial statements to be prepared according to IAS 1 and IAS 7 and, in particular, the so called statement of profit or loss and other comprehensive income for the period are analyzed by underling the function of the same and by presenting some financial performance indicators. Then, the research highlights how these values obtained are not useful to communicate the company's strategy in terms of social responsibility and sustainable value. In the second part the analyses exposes the concept of social balance. According to the social responsibility view the IAS/IFRS financial statements should be accompanied by the social balance. It becomes crucial to complete the set of financial statements stated from IAS 1 with a social balance as well as the same IAS 1 contemplates. For this reason it is possible to say that the connection between IAS/IFRS and social responsibility is weak.

  18. Pharmacokinetics of escin Ia in rats after intravenous administration.

    Science.gov (United States)

    Wu, Xiu-Jun; Cui, Xiang-Yong; Tian, Lian-tian; Gao, Feng; Guan, Xin; Gu, Jing-Kai

    2014-10-28

    Escin, a natural mixture of triterpene saponins, is commonly utilized for the treatment of chronic venous insufficiency, hemorrhoids, inflammation and edema. Escin Ia is the chief active ingredient in escin and plays key role in mediating its pharmacological effects. Adequate pharmacokinetic data are essential for proper application of escin agent in clinical practice. However, pharmacokinetic properties of escin Ia are still poorly understood and this conflicts with the growing use of escin agent over the years. The goal of this study is to investigate the pharmacokinetic behavior of escin Ia in rats after low, medium and high-dose intravenous administration. Wistar rats were divided into 3 groups (n=6 per group) and escin Ia was administered via the caudal vein at doses of 0.5, 1.0 and 2.0 mg/kg, respectively. Subsequently, the concentrations of escin Ia and its metabolite isoescin Ia, a positional isomer of escin Ia, in rats׳ plasma were measured by an established liquid chromatography tandem mass spectrometry (LC-MS/MS) method at various time points following the administration of the drug. Main pharmacokinetic parameters were calculated by non-compartmental analysis using the TopFit 2.0 software package (Thomae GmbH, Germany). After intravenous administration, the Cmax and AUC of escin Ia increased in a dose-proportional manner at the dose of 0.5 mg/kg and 1.0 mg/kg, while increased in a more than dose-proportional manner at the doses of 1.0 mg/kg and 2.0 mg/kg. The t₁/₂ was significantly longer with increased intravenous doses, while other parameters such as CL and Vd also exhibit disagreement among three doses. Taken together, our data showed dose-dependent pharmacokinetic profile of escin Ia in rats after intravenous administration at the doses of 0.5-2.0 mg/kg. After intravenous administration, escin Ia was rapidly and extensively converted to isoescin Ia. The results suggested dose-dependent pharmacokinetics of escin Ia at the doses of 0.5-2.0 mg

  19. Theoretical considerations about implementation of IAS 41 in Romania

    Directory of Open Access Journals (Sweden)

    Liliana FELEAGĂ

    2012-02-01

    Full Text Available Although agriculture is an important part of the world economy, accounting in agriculture still has many shortcomings. The adoption of IAS 41 „Agricuture” has tried to improve this situation and increase the comparability of financial statements of entities in the agricultural sector. Although controversial, IAS 41 is the first step of a consistent transition to fair value assessment in the agricultural sector. The objective of our work is the analysis of IAS 41 and current accounting agricultural situation in Romania. Accounting regulations in Romania are in accordance with European directives and, in many respects, converged with IFRS referential. Provisions of IAS 41, however, are not reflected directly in Romanian regulations. With the increase of forest land transactions and foreign investments in animal farms, it is expected that recognition and measurement of biological assets under IAS 41 to become a necessity.

  20. Status on Bidimensional Dark Energy Parameterizations Using SNe Ia JLA and BAO Datasets

    Directory of Open Access Journals (Sweden)

    Celia Escamilla-Rivera

    2016-07-01

    Full Text Available Using current observations of forecast type Ia supernovae (SNe Ia Joint Lightcurve Analysis (JLA and baryon acoustic oscillations (BAO, in this paper we investigate six bidimensional dark energy parameterizations in order to explore which has more constraining power. Our results indicate that for parameterizations that contain z 2 -terms, the tension (σ-distance between these datasets seems to be reduced and their behaviour is <1σ compatible with the concordance model (ΛCDM. Also, the results obtained by performing their Bayesian evidence show a striking evidence in favour of the ΛCDM model, but only one parameterization can be distinguished by around 1 % from the other models when the combination of datasets are considered.

  1. A cosmographic analysis of the transition to acceleration using SN-Ia and BAO

    Energy Technology Data Exchange (ETDEWEB)

    Muthukrishna, Daniel; Parkinson, David, E-mail: d.muthukrishna@uq.edu.au, E-mail: d.parkinson@uq.edu.au [School of Mathematics and Physics, University of Queensland, Brisbane, QLD 4072 (Australia)

    2016-11-01

    We explore the distance-redshift relation using a cosmographic methodology, and show how the cosmographic parameters can be used to determine the redshift of transition from deceleration to acceleration. Such a transition at a low redshift occupies only a small region of the available parameter space, and the prior assumption of an early period of deceleration can significantly change the posterior constraints. We use available type Ia Supernovae (SN-Ia) and Baryon Acoustic Oscillation (BAO) data sets to determine the cosmographic deceleration q {sub 0}, jerk j {sub 0}, snap s {sub 0} and lerk l {sub 0} parameters. The parameters are consistent with the ΛCDM model for a flat universe within 2-sigma. We derive constraints on the redshift of transition from deceleration to acceleration for the different expansions, and find z {sub acc} > 0.14 at 95% confidence in the most conservative case.

  2. RadNet Air Data From Des Moines, IA

    Science.gov (United States)

    This page presents radiation air monitoring and air filter analysis data for Des Moines, IA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.

  3. RadNet Air Data From Fort Madison, IA

    Science.gov (United States)

    This page presents radiation air monitoring and air filter analysis data for Fort Madison, IA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.

  4. RadNet Air Data From Mason City, IA

    Science.gov (United States)

    This page presents radiation air monitoring and air filter analysis data for Mason City, IA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.

  5. Autologous peptides constitutively occupy the antigen binding site on Ia

    DEFF Research Database (Denmark)

    Buus, S; Sette, A; Colon, S M

    1988-01-01

    Low molecular weight material associated with affinity-purified class II major histocompatibility complex (MHC) molecules of mouse (Ia) had the expected properties of peptides bound to the antigen binding site of Ia. Thus, the low molecular weight material derived from the I-Ad isotype was effici...... peptide-MHC complexes may have broad significance in the biology of T cell responses, including generation of the T cell repertoire, the specificity of mixed lymphocyte responses, and the immune surveillance of self and nonself antigens in peripheral lymphoid tissues.......Low molecular weight material associated with affinity-purified class II major histocompatibility complex (MHC) molecules of mouse (Ia) had the expected properties of peptides bound to the antigen binding site of Ia. Thus, the low molecular weight material derived from the I-Ad isotype...

  6. Muudetud IFRS 3 ja IAS 27 / Monika Peetson

    Index Scriptorium Estoniae

    Peetson, Monika, 1976-

    2008-01-01

    Rahvusvahelise Raamatupidamisstandardite Nõukogu poolt välja antud muudetud standarditest IFRS 3 "Äriühendused" ja IAS 27 "Konsolideeritud ja konsolideerimata finantsaruanded" ning nendega kaasnevatest muudatustest

  7. Enfermidade gastroentérica e respiratória em bezerros inoculados com amostras brasileiras do vírus da diarréia viral bovina tipo 2 (BVDV-2 Gastroenteric and respiratory disease in calves inoculated with brazilian isolates of bovine viral diarrhea virus type 2 (BVDV - 2

    Directory of Open Access Journals (Sweden)

    Mário Celso Sperotto Brum

    2002-10-01

    Full Text Available Duas amostras brasileiras do vírus da Diarréia Viral Bovina tipo 2 (BVDV-2 foram inoculadas em bezerros com o objetivo de avaliar a sua virulência e estudar a patogenia da infecção. Previamente à inoculação, os animais foram imunodeprimidos com dexametasona. Quatro bezerros com idades entre 45 e 90 dias (grupo A foram inoculados com a amostra SV-260 (n=2 ou LV-96 (n=2 e quatro bezerros com 6 a 8 meses de idade foram inoculados com a amostra SV-260 (grupo B. Após a inoculação, os bezerros do grupo A apresentaram anorexia, depressão, hipertermia, sinais de infecção respiratória e diarréia profusa, acompanhada de melena em dois animais. Os sinais respiratórios e digestivos progrediram, e os animais morreram ou foram sacrificados in extremis entre os dias 7 e 12 pós-inoculação. Úlceras e erosões no trato digestivo (língua, n=4; esôfago, n=1; rúmen, n=1 e abomaso, n=3, edema pulmonar (n=4 e na mucosa do abomaso (n=3; equimoses e sufusões na serosa do baço (n=2, no rúmen, no intestino delgado e no ceco (n=1, no coração (n=1 e na mucosa da bexiga (n=1 e intussuscepção intestinal (n=1 foram os achados macroscópicos mais marcantes. Úlceras e erosões, acompanhadas de infiltrado mononuclear na mucosa e submucosa do trato digestivo e depleção linfóide nos linfonodos e placas de Peyer, foram as alterações microscópicas mais freqüentes. O vírus foi detectado em vários tecidos e órgãos. Antígenos virais foram demonstrados por imuno-histoquímica, principalmente em células epiteliais do trato digestivo; em células mononucleares nos espaços perivasculares e peribronquiais; na cápsula e septos de linfonodos; e em linfócitos e células mononucleares das placas de Peyer e baço. Os animais do grupo B apresentaram depressão, hipertermia, sinais moderados de infecção respiratória e digestiva, ulcerações na língua e bochecha, mas recuperaram-se após alguns dias. Esses resultados demonstram que as amostras de

  8. The coupling between the IAS and the IMS

    Energy Technology Data Exchange (ETDEWEB)

    Bes, D.R.; Civitarese, O. E-mail: civitare@fisica.unlp.edu.ar

    2004-09-06

    In a previous paper we have studied the structure of the Isobaric Analogue State (IAS) using a realistic single-particle model within a formalism that allows to disentangle real effects of isospin violations from spurious effects associated with the construction of basis states. In this work we discuss the influence of the Isovector Monopole State (IMS) on the width of the IAS. According to our results, the presence of a collective IMS is necessary to preserve the empirically found isolation of the IAS from states of the background. This is valid for a simplified harmonic oscillator model and for a realistic single-particle basis as well, since for both cases there is a strong Coulomb mixing between the IAS and the IMS, which increases at the expense of decreasing the mixing between the IAS and the {delta}N=0 configuration states. The prediction of the total width of the IAS remains in reasonable agreement with the experimental value in a calculation without free parameters.

  9. Molecular profiling identifies prognostic markers of stage IA lung adenocarcinoma.

    Science.gov (United States)

    Zhang, Jie; Shao, Jinchen; Zhu, Lei; Zhao, Ruiying; Xing, Jie; Wang, Jun; Guo, Xiaohui; Tu, Shichun; Han, Baohui; Yu, Keke

    2017-09-26

    We previously showed that different pathologic subtypes were associated with different prognostic values in patients with stage IA lung adenocarcinoma (AC). We hypothesize that differential gene expression profiles of different subtypes may be valuable factors for prognosis in stage IA lung adenocarcinoma. We performed microarray gene expression profiling on tumor tissues micro-dissected from patients with acinar and solid predominant subtypes of stage IA lung adenocarcinoma. These patients had undergone a lobectomy and mediastinal lymph node dissection at the Shanghai Chest Hospital, Shanghai, China in 2012. No patient had preoperative treatment. We performed the Gene Set Enrichment Analysis (GSEA) analysis to look for gene expression signatures associated with tumor subtypes. The histologic subtypes of all patients were classified according to the 2015 WHO lung Adenocarcinoma classification. We found that patients with the solid predominant subtype are enriched for genes involved in RNA polymerase activity as well as inactivation of the p53 pathway. Further, we identified a list of genes that may serve as prognostic markers for stage IA lung adenocarcinoma. Validation in the TCGA database shows that these genes are correlated with survival, suggesting that they are novel prognostic factors for stage IA lung adenocarcinoma. In conclusion, we have uncovered novel prognostic factors for stage IA lung adenocarcinoma using gene expression profiling in combination with histopathology subtyping.

  10. Bio systematics of two species of the genus globular ia L. in Jordan and Tuns ia (Research Note)

    International Nuclear Information System (INIS)

    Oran, A. S.; Kochkar, N.; Raies, A.

    1999-01-01

    The status of the genus Globular ia L. in Jordan and Tunisia is presented. Bio systematic data related to morphology, habitats, geographical distribution, pollen and seed morphology as revealed by both light and scanning electron microscopy were studied based on material collected from both countries. Based on the collected bio systematic information on, this study has confirmed that only one species Globular ia arabica ac curs in Jordan and one species, G. alypum occurs in Tunisia. (authors). 12 refs., 1 table. 1 fig

  11. Constraints on reconstructed dark energy model from SN Ia and BAO/CMB observations

    Energy Technology Data Exchange (ETDEWEB)

    Mamon, Abdulla Al [Manipal University, Manipal Centre for Natural Sciences, Manipal (India); Visva-Bharati, Department of Physics, Santiniketan (India); Bamba, Kazuharu [Fukushima University, Division of Human Support System, Faculty of Symbiotic Systems Science, Fukushima (Japan); Das, Sudipta [Visva-Bharati, Department of Physics, Santiniketan (India)

    2017-01-15

    The motivation of the present work is to reconstruct a dark energy model through the dimensionless dark energy function X(z), which is the dark energy density in units of its present value. In this paper, we have shown that a scalar field φ having a phenomenologically chosen X(z) can give rise to a transition from a decelerated to an accelerated phase of expansion for the universe. We have examined the possibility of constraining various cosmological parameters (such as the deceleration parameter and the effective equation of state parameter) by comparing our theoretical model with the latest Type Ia Supernova (SN Ia), Baryon Acoustic Oscillations (BAO) and Cosmic Microwave Background (CMB) radiation observations. Using the joint analysis of the SN Ia+BAO/CMB dataset, we have also reconstructed the scalar potential from the parametrized X(z). The relevant potential is found, a polynomial in φ. From our analysis, it has been found that the present model favors the standard ΛCDM model within 1σ confidence level. (orig.)

  12. Interaction of the LILRB1 inhibitory receptor with HLA class Ia dimers.

    Science.gov (United States)

    Baía, Diogo; Pou, Jordi; Jones, Des; Mandelboim, Ofer; Trowsdale, John; Muntasell, Aura; López-Botet, Miguel

    2016-07-01

    Leukocyte immunoglobulin-like receptor subfamily B member 1 (LILRB1) has been reported to interact with a wide spectrum of HLA class I (HLA-I) molecules, albeit with different affinities determined by allelic polymorphisms and conformational features. HLA-G dimerization and the presence of intracellular Cys residues in HLA-B7 have been shown to be critical for their recognition by LILRB1. We hypothesized that dimerization of classical HLA class Ia molecules, previously detected in exosomes, might enhance their interaction with LILRB1. A soluble LILRB1-Fc fusion protein and a sensitive cellular reporter system expressing a LILRB1-ζ chimera were employed to assess receptor interaction with different HLA class Ia molecules transfected in the human lymphoblastoid 721.221 cell line. Under these conditions, intracellular Cys residues and HLA-I dimerization appeared associated with increased LILRB1 recognition. On the other hand, a marginal interaction of LILRB1 with primary monocytic cells, irrespective of their high HLA-I expression, was enhanced by type I interferon (IFN). This effect appeared disproportionate to the cytokine-induced increase of surface HLA-I expression and was accompanied by detection of HLA class Ia dimers. Altogether, the results support that a regulated assembly of these noncanonical HLA-I conformers during the immune response may enhance the avidity of their interaction with LILRB1. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Ethics and Esthetics in Holocaust Images. Case study: the Iași Pogrom

    Directory of Open Access Journals (Sweden)

    Anca Tudorancea (Ciuciu

    2014-09-01

    Full Text Available The article refers to the negative images rediscovered in recent Romanian history, images of the Iași pogrom of June 28 to 30, 1941, that still triggers rejection reactions in different environments. The fate of these images that were to be destroyed after the event is as interesting as the recent revaluation of the data base of images, which is found today in various archives. In multiple frames civilian witnesses can be seen passing by scenes showing executions and bodies of Jewish children, women and men. Talking about the event is still rare within hours of Romanian history or public setting, often even in Iași, where many teachers prefer to talk about images related to Poland and concentration camps. Also using images from Iași pogrom without interpretations can lead in time to the same type of abuse of the image as in Auschwitz case, a negative stereotype that shows an abused victim exposed of our sight.

  14. Probing the cosmic distance duality with strong gravitational lensing and supernovae Ia data

    Energy Technology Data Exchange (ETDEWEB)

    Holanda, R.F.L. [Departamento de Física, Universidade Estadual da Paraíba, 58429-500, Campina Grande PB (Brazil); Busti, V.C. [Departamento de Física Matemática, Instituto de Física, Universidade de São Paulo, CP 66318, CEP 05508-090, São Paulo SP (Brazil); Alcaniz, J.S., E-mail: holanda@uepb.edu.br, E-mail: vcbusti@astro.iag.usp.br, E-mail: alcaniz@on.br [Departamento de Astronomia, Observatório Nacional, 20921-400, Rio de Janeiro RJ (Brazil)

    2016-02-01

    We propose and perform a new test of the cosmic distance-duality relation (CDDR), D{sub L}(z) / D{sub A}(z) (1 + z){sup 2} = 1, where D{sub A} is the angular diameter distance and D{sub L} is the luminosity distance to a given source at redshift z, using strong gravitational lensing (SGL) and type Ia Supernovae (SNe Ia) data. We show that the ratio D=D{sub A{sub 1{sub 2}}}/D{sub A{sub 2}} and D{sup *}=D{sub L{sub 1{sub 2}}}/D{sub L{sub 2}}, where the subscripts 1 and 2 correspond, respectively, to redshifts z{sub 1} and z{sub 2}, are linked by D/D{sup *}=(1+z{sub 1}){sup 2} if the CDDR is valid. We allow departures from the CDDR by defining two functions for η(z{sub 1}), which equals unity when the CDDR is valid. We find that combination of SGL and SNe Ia data favours no violation of the CDDR at 1σ confidence level (η(z) ≅ 1), in complete agreement with other tests and reinforcing the theoretical pillars of the CDDR.

  15. ROŞIA MONTANĂ-ABRUD AURIFEROUS AREA AT CROSSROADS: INTENSIVE MINING EXPLOITATION VERSUS TOURISTIC CAPITALIZATION

    Directory of Open Access Journals (Sweden)

    MARIA-ADINA JURJ

    2014-11-01

    Full Text Available Roşia Montană-Abrud auriferous area at crossroads: intensive mining exploitation versus touristic capitalization. Roşia Montană-Abrud is a mining area located in the North-Eastern side of the Metaliferi (Metalliferous Mountains, part of the Apuseni Mountains, and holds the biggest gold and silver ores deposit in Europe. It also belongs to the Gold (or Auriferous Quadrilateral, an important metalliferous region which covers around 2500 km2 between Baia de Arieş-Zlatna-Săcărâmb-Ţebea. Roşia Montană, the oldest mining locality in Romania, enhanced even more its fame after the apparition of Roşia Montană Gold Corporation (RMGC, a Romanian-Canadian mining company which, according to its claims, intends to exploit (even if it has-legally-only an exploration licence the existing 300 tons of gold and 1600 tons of silver, by usind cyanide. In order to store the approximately 200 000 tons of residual cyanides, the company intends to built a huge tailings pond (about 180 m height and 800 ha in Corna Valley. By comparison, the Bozânta tailings pond near Baia Mare, which broke down in 2000, had only about 90 ha. On the other side, the opponents of the RMGC project aims to protect both natural and cultural heritage, which embed a richness of archaeological, historical and architectural objectivs, particularly. Also, there have been found arguments for the inscription of the area in UNESCO World Heritage Tentative List. This study aims also to highlight the main types of tourism feasible for the mentioned area.

  16. Immunogenetics of type 1 diabetes mellitus

    African Journals Online (AJOL)

    EL-HAKIM

    and components of the complement system. These histological ... Children who progress to T1D have IAAs of high affinity15 and also develop GADAs concomitantly or soon after the first IAA response. Spreading of the response to. IA-2 and IA-2Я often .... Early feeding may influence the risk of type 1. (T1D) later in life.

  17. Investigating the diversity of supernovae type Iax

    DEFF Research Database (Denmark)

    Lyman, J. D.; Taddia, F.; Stritzinger, M. D.

    2018-01-01

    SN 2002cx-like Type Ia supernovae (also known as SNe Iax) represent one of the most numerous peculiar SN classes. They differ from normal SNe Ia by having fainter peak magnitudes, faster decline rates and lower photospheric velocities, displaying a wide diversity in these properties. We present b...

  18. Adoption of IFRS/IAS impacting the companies

    Directory of Open Access Journals (Sweden)

    Michaela Baranová

    2013-11-01

    Full Text Available In recent time, there were done marked changes in IAS/IFRS, changes in existing rules. Fifteen standards of IAS have been amended just before the end of 2003 and in course of the first quarter of the year 2004 updating of other standards IAS has been done. The requirement of changes hangs together, among others, also with the recent affairs about the bankruptcies of big companies. In this connection, accelerated and turning changes are proceeding in EU. Since 2005 every EU listed company has to prepare the consolidated financial statements in accordance with IFRS/IAS. Vast survey on the impacts of IFRS adoption was carried by Mazars in 2005. 25 Czech companies have been also interviewed within the study. These Czech companies have exhibit a strong mastery and readiness for the conversion and transition process. Such a summary is quite unwonted in a number of perspectives. But the aim of the author is not to question the study. In the Czech environment, the specific facts in the field of financial reporting and accounting are given. Following these specifics, the truth is that preparing the financial statements in accordance with IFRS/IAS brings undoubtedly valuation and technical entanglements for which the process is costly.

  19. Evaluation of the new IASLC/ATS/ERS proposed classification of adenocarcinoma based on lepidic pattern in patients with pathological stage IA pulmonary adenocarcinoma.

    Science.gov (United States)

    Nakagiri, Tomoyuki; Sawabata, Noriyoshi; Morii, Eiichi; Inoue, Masayoshi; Shintani, Yasushi; Funaki, Soichiro; Okumura, Meinoshin

    2014-11-01

    The International association for the study of cancer (IASLC)/American thoracic society (ATS)/European respiratory society (ERS) has established a new subclassification of lung adenocarcinoma, especially for the lepidic pattern component, formerly called bronchioloalveolar adenocarcinoma (BAC). According to the new classification, BAC has been classified into the following 4 main subtypes: adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), invasive adenocarcinoma (IA), and variants of invasive adenocarcinoma (VIA). An observational study was conducted to validate this classification in patients with pathological stage IA pulmonary adenocarcinoma. 147 patients treated for pathological stage IA lung adenocarcinoma by complete resection at Osaka University Medical Hospital from January 1993 to December 2002 were assessed. The tumor specimens of the cohort were classified into the 4 subgroups. In addition, these groups were compared for various prognostic factors. Adenocarcinoma in situ was observed in 30 patients, MIA in 8, IA in 104, and VIA in 5 patients, with 5-year survival rates of 100, 100, 85.5, and 60.0 %, respectively. The relationship between the histological classification and K-ras mutation was significant (p classification for pulmonary adenocarcinoma in patients with pathological stage IA pulmonary adenocarcinoma. The difference between AIS and IA may depend on the proliferation of the carcinoma. In addition, the difference between VIA and the other adenocarcinoma types may depend on genetic factors, especially K-ras mutations.

  20. IAS 39 og konverterbar gæld

    DEFF Research Database (Denmark)

    Fredslund Møller, Peder; Thinggaard, Frank

    , at der er en betydelig beholdning af konverterbare realkreditlån, som der skal aflægges regnskab for. Denne artikel har til formål at belyse de alternativer, der findes i IAS39 til regnskabsmæssig behandling af konverterbar gæld. I juli 2008 kom der en tilføjelse til IAS 39, "Eligible Hedged Items". Den......: 1. dagsværdimetode, hvor "hele det konverterbare lån", dvs. både den "rene gæld" og den indbyggede indfrielsesoption, der iflg. IAS 39 udgør de to komponenter i et konverterbart lån, føres til dagsværdi, 2. udskillelsesmetode, hvor der anvendes amortiseret kostpris for den "rene gæld" og dagsværdi...

  1. Consolidated Financial Statements – in IAS 27 perspective

    Directory of Open Access Journals (Sweden)

    Mihai Deju

    2012-12-01

    Full Text Available The aspects concerning the preparation and publication of the consolidated financial statements have been the subject of the settlement by the Committee for International Accounting Standards (IAS even since 1976 with the publication of IAS 3 “Consolidated financial statements”. Subsequently, the standard has been amended and revised successively, on several occasions. The latest version issued in 2008 includes changes on the accounting of interests that do not control and the loss of control on a subsidiary. The actual version also includes the subsequent amendments resulting from IFRS issued until 31st of December 2010. This paper presents the essential aspects of IAS 27 (the actual version and a practical example of how to elaborate consolidated accounts in accordance with this standard.

  2. Tillämpning av IAS 40 i onoterade fastighetsbolag

    OpenAIRE

    Wallin, Fredrik; Nilsson, Karolina; Ericsson, Marina

    2006-01-01

    Enligt IAS 40 – Förvaltningsfastigheter, definieras förvaltningsfastigheter som ”mark eller byggnader eller del av byggnad som innehas i syfte att generera hyresinkomster eller värdestegring”. Onoterade fastighetsbolag i Sverige har idag möjlighet att välja mellan att värdera sina fastigheter till anskaffningsvärde eller verkligt värde. IAS – International Accounting Standards är en internationell redovisningsstandard inom EU som började tillämpas i januari 2001, men blev obligatorisk för bör...

  3. Diarréia por parasitas Parasites induced diarrheas

    Directory of Open Access Journals (Sweden)

    Maria Eugênia Farias Almeida Motta

    2002-08-01

    Full Text Available A diarréia é uma causa importante de morbimortalidade nos países em desenvolvimento. Os agentes etiológicos mais comuns são os vírus e as bactérias. Este artigo tem o objetivo de analisar a ocorrência de diarréia como manifestação clínica de parasitose. Discute-se quais os protozoários e os helmintos que podem causar diarréia, as bases científicas atuais que explicam os mecanismos fisiopatológicos que desencadeiam a diarréia, bem como os exames complementares e o tratamento adequado para cada parasita implicado.Diarrhea is an important cause of morbidity and mortality in developing countries. The most common etiological agents are viruses and bacteria. This article has the objective of analyzing diarrhea as a clinical symptom of parasitosis. Protozoa and helminthes that may cause diarrhea are discussed, current scientific basis clarifying the pathological and physiological mechanisms causing diarrhea as well as supplementary tests and adequate treatment for each parasite involved are focused.

  4. 78 FR 53492 - Iowa Disaster Number IA-00053

    Science.gov (United States)

    2013-08-29

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13699 and 13700] Iowa Disaster Number IA-00053 AGENCY: U.S. Small Business Administration. Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA- 4135-DR...

  5. 75 FR 57088 - Iowa Disaster Number IA-00026

    Science.gov (United States)

    2010-09-17

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12258 and 12259] Iowa Disaster Number IA-00026 AGENCY: U.S. Small Business Administration. ACTION: Amendment 3. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA- 1930-DR...

  6. 76 FR 80446 - Iowa Disaster Number IA-00033

    Science.gov (United States)

    2011-12-23

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12895 and 12896] Iowa Disaster Number IA-00033 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for the State of Iowa (FEMA-1998-DR), dated 10/18/2011. Incident...

  7. 78 FR 51262 - Iowa Disaster Number IA-00054

    Science.gov (United States)

    2013-08-20

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13645 and 13646] Iowa Disaster Number IA-00054 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA-- 4126--DR...

  8. 75 FR 59750 - Iowa Disaster Number IA-00026

    Science.gov (United States)

    2010-09-28

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12258 and 12259] Iowa Disaster Number IA-00026 AGENCY: U.S. Small Business Administration. ACTION: Amendment 5. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA- 1930-DR...

  9. 75 FR 52048 - Iowa Disaster Number IA-00024

    Science.gov (United States)

    2010-08-24

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12279 and 12280] Iowa Disaster Number IA-00024 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for the State of Iowa (FEMA-1930-DR), dated 08/14/2010. Incident...

  10. 75 FR 57997 - Iowa Disaster Number IA-00024

    Science.gov (United States)

    2010-09-23

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12279 and 12280] Iowa Disaster Number IA-00024 AGENCY: U.S. Small Business Administration. ACTION: Amendment 2. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for the State of Iowa (FEMA-1930-DR), dated 08/14/2010. Incident...

  11. 76 FR 56863 - Iowa Disaster Number IA-00036

    Science.gov (United States)

    2011-09-14

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12754 and 12755] Iowa Disaster Number IA-00036 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA- 1998-DR...

  12. 75 FR 76294 - Radio Broadcasting Services: Pacific Junction, IA

    Science.gov (United States)

    2010-12-08

    ... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 73 [DA 10-2236; MB Docket No. 10-108] Radio Broadcasting Services: Pacific Junction, IA AGENCY: Federal Communications Commission. ACTION: Final rule. SUMMARY: The staff deletes FM Channel 299C2 at Pacific Junction, Iowa, because the record in this...

  13. 75 FR 62897 - Iowa Disaster Number IA-00024

    Science.gov (United States)

    2010-10-13

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12279 and 12280] Iowa Disaster Number IA-00024 AGENCY: U.S. Small Business Administration. ACTION: Amendment 4. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for the State of IOWA (FEMA-1930-DR), dated 08/14/2010. Incident...

  14. 75 FR 51506 - Iowa Disaster Number IA-00026

    Science.gov (United States)

    2010-08-20

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12258 and 12259] Iowa Disaster Number IA-00026 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA- 1930-DR...

  15. 75 FR 57996 - Iowa Disaster Number IA-00026

    Science.gov (United States)

    2010-09-23

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12258 and 12259] Iowa Disaster Number IA-00026 AGENCY: U.S. Small Business Administration. ACTION: Amendment 4. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA- 1930-DR...

  16. 75 FR 17178 - Iowa Disaster Number IA-00023

    Science.gov (United States)

    2010-04-05

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12062 and 12063] Iowa Disaster Number IA-00023 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA- 1880-DR...

  17. 75 FR 58451 - Iowa Disaster Number IA-00024

    Science.gov (United States)

    2010-09-24

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12279 and 12280] Iowa Disaster Number IA-00024 AGENCY: U.S. Small Business Administration. ACTION: Amendment 3. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for the State of Iowa (FEMA-1930-DR), dated 08/14/2010. Incident...

  18. 75 FR 65390 - Iowa Disaster Number IA-00024

    Science.gov (United States)

    2010-10-22

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12279 and 12280] Iowa Disaster Number IA-00024 AGENCY: U.S. Small Business Administration. ACTION: Amendment 5. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for the State of Iowa (FEMA--1930--DR), dated 08/14/ 2010...

  19. 78 FR 38781 - Iowa Disaster Number IA-00052

    Science.gov (United States)

    2013-06-27

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13605 and 13606] Iowa Disaster Number IA-00052 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the State of Iowa (FEMA- 4119-DR...

  20. Tax accounting - IFRS IAS 12 : Voor accountants, controllers en fiscalisten

    NARCIS (Netherlands)

    Naarding, E.; Langendijk, H.P.A.J.

    2010-01-01

    Deel 7 van de reeks 'Tax Assurance in beeld' is een werkboek dat vraagstukken bevat om de technische aspecten van IAS 12 Income Taxes van de International Accounting Standards Board (IASB) te oefenen. Het boek is bedoeld voor ac