2,390 research outputs found
Mitochondrial haplogroups associated with elite Japanese athlete status
Purpose It has been hypothesised that certain mitochondrial haplogroups, which are defined by the presence of a characteristic cluster of tightly linked mitochondrial DNA polymorphisms, would be associated with elite Japanese athlete status. To examine this hypothesis, the frequencies of mitochondrial haplogroups found in elite Japanese athletes were compared with those in the general Japanese population. Methods Subjects comprised 139 Olympic athletes (79 endurance/middle-power athletes (EMA), 60 sprint/power athletes (SPA)) and 672 controls (CON). Two mitochondrial DNA fragments containing the hypervariable sequence I (m16024-m16383) of the major non-coding region and the polymorphic site at m. 5178C>A within the NADH dehydrogenase subunit 2 gene were sequenced, and subjects were classified into 12 major mitochondrial haplogroups (ie, F, B, A, N9a, N9b, M7a, M7b, M*, G2, G1, D5 or D4). The mitochondrial haplogroup frequency differences among EMA, SPA and CON were then examined. Results EMA showed an excess of haplogroup G1 (OR 2.52, 95% CI 1.05 to 6.02, p=0.032), with 8.9% compared with 3.7% in CON, whereas SPA displayed a greater proportion of haplogroup F (OR 2.79, 95% CI 1.28 to 6.07, p=0.007), with 15.0% compared with 6.0% in CON. Conclusions The results suggest that mitochondrial haplogroups G1 and F are associated with elite EMA and SPA status in Japanese athletes, respectivel
A major star formation region in the receding tip of the stellar Galactic bar
We present an analysis of the optical spectroscopy of 58 stars in the
Galactic plane at \arcdeg, where a prominent excess in the flux
distribution and star counts have been observed in several spectral regions, in
particular in the Two Micron Galactic Survey (TMGS) catalog. The sources were
selected from the TMGS, to have a magnitude brighter than +5 mag and be
within 2 degrees of the Galactic plane. More than 60% of the spectra correspond
to stars of luminosity class I, and a significant proportion of the remainder
are very late giants which would also be fast evolving. This very high
concentration of young sources points to the existence of a major star
formation region in the Galactic plane, located just inside the assumed origin
of the Scutum spiral arm. Such regions can form due to the concentrations of
shocked gas where a galactic bar meets a spiral arm, as is observed at the ends
of the bars of face-on external galaxies. Thus, the presence of a massive star
formation region is very strong supporting evidence for the presence of a bar
in our Galaxy.Comment: 13 pages (latex) + 4 figures (eps), accepted in ApJ Let
A new infrared band in the Interstellar and Circumstellar Clouds: C_4 or C_4H?
We report on the detection with the Infrared Space Observatory (ISO) of a
molecular band at 57.5 microns (174 cm^{-1}) in carbon-rich evolved stars and
in Sgr B2. Taking into account the chemistry of these objects the most
likelihood carrier is a carbon chain. We tentatively assign the band to the
nu_5 bending mode of C_4 for which a wavenumber of 170-172.4 cm^{-1} has been
derived in matrix experiments (Withey et al. 1991). An alternate carrier might
be C_4H, although the frequency of its lowest energy vibrational bending mode,
nu_7, is poorly known (130-226 cm^{-1}). If the carrier is C_4, the derived
maximum abundance is nearly similar to that found for C_3 in the interstellar
and circumstellar media by Cernicharo, Goicoechea & Caux (2000). Hence,
tetra-atomic carbon could be one of the most abundant carbon chain molecules in
these media.Comment: 11 pages, 1 figure, accepted in ApJ Letter
Infrared study of spin crossover Fe-picolylamine complex
Infrared (IR) absorption spectroscopy has been used to probe the evolution of
microscopic vibrational states upon the temperature- and photo-induced spin
crossovers in [Fe(2-picolylamine)3]Cl2EtOH (Fe-pic). To overcome the small
sizes and the strong IR absorption of the crystal samples used, an IR
synchrotron radiation source and an IR microscope have been used. The obtained
IR spectra of Fe-pic show large changes between high-spin and low-spin states
for both the temperature- and the photo- induced spin crossovers. Although the
spectra in the temperature- and photo-induced high-spin states are relatively
similar to each other, they show distinct differences below 750 cm-1. This
demonstrates that the photo-induced high-spin state involves microscopically
different characters from those of the temperature-induced high-spin state. The
results are discussed in terms of local pressure and structural deformations
within the picolylamine ligands, and in terms of their possible relevance to
the development of macroscopic photo-induced phase in Fe-pic.Comment: 6 pages (text) and 6 figures,submitted to J. Phys. Soc. Jp
The cDNA and deduced amino acid sequence of the γ subunit of the L-type calcium channel from rabbit skeletal muscle
Complementary DNAs for the γ subunit of the calcium channel of rabbit skeletal muscle were isolated on the basis of peptide sequences derived from the purified protein. The deduced primary structure is without homology to other known protein sequences and is consistent with the γ subunit being an integral membrane protein
A Multi-Wavelength, Multi-Epoch Study of the Soft X-Ray Transient Prototype, V616 Mon (A0620-00)
We have obtained optical and infrared photometry of the soft x-ray transient
prototype V616 Mon (A0620-00). From this photometry, we find a spectral type of
K4 for the secondary star in the system, which is consistent with spectroscopic
observations. We present J-, H-, and K-band light curves modeled with WD98 and
ELC. Combining detailed, independently run models for ellipsoidal variations
due to a spotted, non-spherical secondary star, and the observed ultraviolet to
infrared spectral energy distribution of the system, we show that the most
likely value for the orbital inclination is 40.75 +/- 3 deg. This inclination
angle implies a primary black hole mass of 11.0 +/- 1.9 solar masses.Comment: 29 pages (preprint format), including 7 figures and 4 tables,
accepted for publication in the Nov 2001 issue of A
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