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The purposes of this study were to investigate the distribution characteristics of CAG repeat polymorphism in exon 1 of androgen receptor gene and the association of CAG polymorphism with VO₂max response to hypoxic training in North China Han men. Sixty-five healthy young men completed a 30-day HiHiLo training (living high, exercise high and training low) in a simulated normobaric hypoxic environment. All subjects slept in 14.3-14.8% O₂ concentration, and participated in hypoxic training three times a week in 15.4% O₂ concentration. VO₂max (peak oxygen consumption) and body weight were measured before and after hypoxic training. A total of 15 repeat alleles were observed by CAG genotype analyze, in which (CAG)22 was most common. When using 21 and 22 alleles, respectively, as cut-off points, we found that the baseline body weight of two shorter genotype groups was significantly lower than that of longer ones, and that the ΔVO₂max and ΔrVO₂max (Δrelative value of VO₂max) of two shorter genotype groups were significantly higher than those of longer ones after hypoxic training. These findings indicated that AR CAG repeat polymorphism was associated with the exercise performance after simulated normobaric hypoxic HiHiLo training in North China Han men, and that the shorter genotypes had a better individual response to hypoxic training.

Nanosized TiO2 particles coated with dodecylbenzenesulfonic acid (DBS) and stearic acid (St) were prepared using the hydrothermal procedure. The average size of the DBS/TiO2 and St/TiO2 particles is very small, about 8 nm. Raman spectra from DBS/TiO2 and St/TiO2 were measured, and scattering signals from both TiO2 and the coating were observed. It was found that in contrast to the red shift of Raman peaks in the nanoparticles with decrease in particle size, a blue shift, namely the Raman peak shift to the higher wavenumber side, in the coated particles was recorded. It was also found that different coatings show different extents of Raman shifts. The possible origin of the blue shift is discussed. Copyright © 2001 John Wiley & Sons, Ltd.

New cuprates of composition (Cd 0.5 M 0.5 )Sr 2 YCu 2 O 7 (M=Fe, Co) with the 1212 structure are synthesized. X-ray diffraction patterns show that both cuprates exhibit a tetragonal 1212-phase structure. The lattice parameters of (Cd 0.5 Fe 0.5 )Sr 2 YCu 2 O 7 are a = 3.809 A and c = 11.423 A ; those of (Cd 0.5 Co 0.5 )Sr 2 YCu 2 O 7 are a = 3.816 A and c = 11.435 A. The results of electron diffraction for the samples show that there is a 90° twinning of the c-axis. The Raman spectra depict an apical-O(2) vibration mode appearing at 544 cm -1 for (Cd 0.5 Fe 0.5 )Sr 2 YCu 2 O 7 and 535 cm -1 for (Cd 0.5 Co 0.5 )Sr 2 YCu 2 O 7 . The samples act as semiconductors in the temperature range 12 to 300 K.