272 research outputs found
Alternative splicing in the fragile X gene <i>FMR1</i>
Human Molecular Genetics 2 pp. 399-404 (1993)The authors wish to note a mistake which was incorporated in figure 3 where both Asp and Asn were given the letter code N. A correct version of the figure and its legend is printed below.</p
Alternative splicing in the fragile X gene <i>FMR1</i>
Human Molecular Genetics 2 pp. 399-404 (1993)The authors wish to note a mistake which was incorporated in figure 3 where both Asp and Asn were given the letter code N. A correct version of the figure and its legend is printed below.</p
New Spectroscopic Observations of the Post-AGB Star V354Lac=IRAS22272+5435
The strongest absorption features with the lower-level excitation potentials
eV are found to be split in the high-resolution optical
spectra of the post-AGB star V354 Lac taken in 2007--2008. Main parameters,
T=5650 K, =0.2, =5.0 km/s, and the abundances of 22
chemical elements in the star's atmosphere are found. The overabundance of the
-process chemical elements (Ba, La, Ce, Nd) in the star's atmosphere is
partly due to the splitting of strong lines of the ions of these metals. The
peculiarities of the spectrum in the wavelength interval containing the LiI
6707 \AA{} line can be naturally explained only by taking the
overabundances of the CeII and SmII heavy-metal ions into account. The best
agreement with the synthetic spectrum is achieved assuming (LiI)=2.0,
(CeII)=3.2, and (SmII)=2.7. The velocity field both in the
atmosphere and in the circumstellar envelope of V354 Lac remained stationary
throughout the last 15 years of our observations.Comment: 16 pages, 6 figures, 2 table
V2324Cyg - an F-type star with fast wind
For the first time high-resolution optical spectroscopy of the variable star
V2324Cyg associated with the IR-source IRAS20572+4919 is made. More than 200
absorption features (mostly FeII, TiII, CrII, YII, BaII, and YII) are
identified within the wavelength interval 4549-7880AA. The spectral type and
rotation velocity of the star are found to be F0III and Vsini=69km/s,
respectively. HI and NaID lines have complex PCyg-type profiles with an
emission component. Neither systematic trend of radial velocity Vr with line
depth Ro nor temporal variability of Vr have been found. We determined the
average heliocentric radial velocity Vr=-16.8\pm 0.6km/s. The radial velocities
inferred from the cores of the absorption components of the H and NaI
wind lines vary from -140 to -225km/s (and the expansion velocities of the
corresponding layers, from about 120 to 210km/s). The maximum expansion
velocity is found for the blue component of the split H absorption:
450km/s for December 12, 1995. The model atmospheres method is used to
determine the star's parameters: Teff=7500K, log g=2.0, =6.0km/s, and
metallicity, which is equal to the solar value. The main peculiarity of the
chemical abundances pattern is the overabundance of lithium and sodium. The
results cast some doubt on the classification of V2324Cyg as a post-AGB star.Comment: 28 pages, 6 figure
The optically bright post-AGB population of the LMC
The detected variety in chemistry and circumstellar shell morphology of the
limited sample of Galactic post-AGB stars is so large that there is no
consensus yet on how the different objects are linked by evolutionary channels.
The evaluation is complicated by the fact that their distances and hence
luminosities remain largely unknown. Via cross-correlation of the Spitzer SAGE
catalogue with optical catalogues we selected a sample of LMC post-AGB
candidates based on their [8]-[24] colour index and estimated luminosity. We
determined the fundamental properties of the central stars of 105 of these
objects using low-resolution, optical spectra that we obtained at Siding Spring
Observatory and SAAO, and constructed a catalogue of 70 high probability and
1337 candidate post-AGB stars that is available at the CDS. The sample forms an
ideal testbed for stellar evolution theory predictions of the final phase of
low- and intermediate-mass stars, because the distance and hence luminosity and
also the current and initial mass of these objects is well constrained. About
half of the objects in our sample of post-AGB candidates show a spectral energy
distribution (SED) that is indicative of a disc rather than an expanding and
cooling AGB remnant. Like in the Galaxy, the disc sources are likely associated
with binary evolution. Important side products of this research are catalogues
of candidate young stellar objects, candidate supergiants with circumstellar
dust, and discarded objects for which a spectrum was obtained. These too are
available at the CDS
An Eco RI RFLP in the 5′ region of the human NF1 gene
Von Recklinghausen neurofibromatosis or type l neurofibromatosis (NF1), is one of the most common autosomal dominant disorders. NF1 is characterized by neurofibromas, café-au-lait spots and Lisch nodules of the iris. The NF1 gene is located in 17q11.2. The restriction fragment length polymorphism reported here will be useful in linkage analysis in NF1 families.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47634/1/439_2004_Article_BF00420953.pd
Towards ensemble asteroseismology of the young open clusters Chi Persei and NGC 6910
As a result of the variability survey in Chi Persei and NGC6910, the number
of Beta Cep stars that are members of these two open clusters is increased to
twenty stars, nine in NGC6910 and eleven in Chi Persei. We compare pulsational
properties, in particular the frequency spectra, of Beta Cep stars in both
clusters and explain the differences in terms of the global parameters of the
clusters. We also indicate that the more complicated pattern of the variability
among B type stars in Chi Persei is very likely caused by higher rotational
velocities of stars in this cluster. We conclude that the sample of pulsating
stars in the two open clusters constitutes a very good starting point for the
ensemble asteroseismology of Beta Cep-type stars and maybe also for other
B-type pulsators.Comment: 4 pages, Astronomische Nachrichten, HELAS IV Conference, Arecife,
Lanzarote, Feb 2010, submitte
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