Characterization of pigmented granules in minocycline-induced cutaneous pigmentation: observations using fluorescence microscopy and high-performance liquid chromatography

Ambiguous abdominal situs, asplenia/polysplenia and severe cardiac malformations characterize heterotaxy in humans. These anomalies result from the inability of the developing embryo to establish normal left-right asymmetry. We have studied an interesting family in which the heterotaxy phenotype segregates as an X-linked recessive trait. In order to map the heterotaxy locus (HTX), we have analysed 39 family members using highly-polymorphic microsatellite markers from the X chromosome. One of these markers, DXS994, shows no recombination with the disease locus in 20 informative meioses. Linkage analysis results in a maximum lod score of 6.37. Current genetic and physical mapping data assign the order of loci in Xq24-q27.1 as cen-DXS1001-(DXS994, HTX)-DXS984-tel. These results establish the first mapping assignment of situs abnormalities in humans.     

Superconductivity in W-containing diamond-like nanocomposite films

Superconductivity in a tungsten-containing carbon-oxide film was reported. The film with 500 nm thickness was deposited onto polycrystalline silicon oxides using chemical vapor deposition and the co-sputtering of a tungsten metal target. The bonding state of the carbon atoms and the macroscopic and microscopic crystal structure of the film were investigated by Raman spectroscopy, X-ray diffraction and transmission electron microscopy measurements. From the experimental results, we determined that this film essentially had an amorphous structure. The temperature dependence on resistivity was measured in the temperature range of 2–300 K. Resistive superconducting transition was observed at 3.8 K. The dc magnetizations were measured in the temperature range of 1.8–6.5 K. The diamagnetism resulting from a superconductive state was observed below 3.75 K, which is consistent with a resistive superconducting transition. It is thought that the finite sized clusters of the different superconductive transition temperatures cooperatively produce a macroscopic superconducting phenomenon.     

Characterization of highly active silver catalyst for NOx reduction in lean-burning engine exhaust

A new Ag/Al₂O₃ catalyst for removing NOx in lean exhaust gas was developed. Oxidized Ag/Al₂O₃ catalyst is highly active for reduction of NOx with ethanol and propene, whereas reduced Ag/Al₂O₃ catalyst is less active for these reactions. Selectivity to N₂ is also high on the oxidized Ag/Al₂O₃ compared to that on the reduced Ag/Al₂O₃. XRD and SEM studies of these two types of Ag catalysts suggest that oxidation induces an interaction between Ag and the support, where the particles are grown in large size. In contrast, the metallic Ag particles are finely dispersed by the reduction process. Although dispersion of Ag particles is decreased by the oxidation process, the catalytic activity is increased. This suggests that the Ag-alumina sites created in the high temperature oxidizing environment are active in catalytic reduction of NOx. This revised version was published online in July 2006 with corrections to the Cover Date.     

Viscoelastic characterization of moderately concentrated polystyrene solutions by dynamic light scattering

The dynamic light scattering measurements were performed for moderately concentrated entangled solutions of atactic polystyrene in benzene (BZ) at 25.0 °C, in cyclohexane (CH) at 34.5 °C (Θ), and in diethyl malonate (DEM) at 35.0 °C (Θ) to characterize their viscoelastic properties. The results have shown that while the mutual diffusion coefficient D increases in the BZ solutions and decreases in the CH and DEM solutions with increasing polymer mass concentration c, the friction coefficient ζ for the three solutions increases with c showing the same power-law behavior irrespective of the weight-average molecular weight M_w and solvent quality. It has been found that the instantaneous longitudinal modulus L₀ for the CH and DEM solutions increases in proportion to c², obeying the familiar relation for the plateau value (4/3)G_N of the longitudinal stress relaxation modulus, but the L₀ values for these solutions are somewhat smaller than the values predicted from the relation. The terminal relaxation time τ_m for the two Θ solvent systems has been found to follow the power-law τ_m∝c^2.7, showing good correspondence to the relation established by rheological measurements.     

Bacteriological, pharmacokinetic and clinical evaluation of azithromycin in the pediatric field]

Azithromycin (AZM), a new macrolide antibiotic, in fine granules and in capsules was studied for pharmacokinetic and clinical evaluation in the pediatric patients. Antibacterial activity of AZM against 43 clinical isolates: AZM exhibited slightly lower activity against Gram-positive bacteria and 2-8-fold higher activity against Gram-negative bacteria than erythromycin or clarithromycin. Plasma or urine samples were collected from eight patients receiving the drug in fine granular form, and two patients receiving it in capsules for the determination of drug levels. The elimination half-lives of AZM after administration at dose of 10 mg/kg/day for 3 days were 50.0 and 51.2 hours for fine granules, and 41.5 hours for capsules. AUC0-infinity was 11.7 and 24.3 micrograms.hr/ml for fine granules, and 8.3 micrograms.hr/ml for capsules. The cumulative excretion rates up to 120 hours after the start of treatment were 8.24 and 13.84% for fine granules, and 3.83% for capsules. AZM was administered to 123 patients once daily at 3.7-20.0 mg/kg body weight over 3 to 5 days with reference to the standard dose of 10 mg/kg. The drug was used to treat patients with pharyngitis, tonsillitis, scarlet fever, pneumonia, mycoplasmal pneumonia, chlamydial pneumonia, otitis media, pertussis, intestinal infection, and SSTI. The effectiveness of AZM was evaluated in 109 cases. The drug was rated "excellent" in 65.1% of the patients and "good" in 29.4%, resulting in an efficacy rate of 94.5%. Furthermore, AZM eradicated 43 of 46 (93.5%) bacteria that had been identified before the treatment. Three patients complained of side effects of urticaria (1 case) and diarrhea (2 cases). Abnormal laboratory changes were reported as follows: decreased leukocyte (3 cases), increased eosinophil (5), increased platelet (2), increased eosinophil and platelet, elevated GPT (1), and elevated GOT and GPT (1). The abnormalities, however, were mild enough to raise no clinically significant problems. In conclusion, AZM in once daily regimen was effective and safe in treatment of pediatric infections.     

Improvement in D-E Hysteresis Curve Squareness of PZT Thin Films—Effect of Oxygen Partial Pressure in High-Pressure Post-Annealing

A high-pressure annealing was applied to a post-annealing process for sol-gel derived PZT thin films. The squareness of D-E hysteresis curves changes depending on both total pressure and oxygen concentration. Moreover, the change follows the product of the total pressure and the oxygen concentration, which correspond to oxygen partial pressure P_O2. Where the P_O2 is higher than 0.03 MPa, few of the squareness of the hysteresis curve are excellent. The squareness of the hysteresis curves dramatically improve as the P_O2 decreases. Where the P_O2 is lower than 0.01 MPa, the squareness deteriorates slightly. These changes in the D-E hysteresis curves are thought to be explained by the generation of lead and oxygen vacancies as a function of the P_O2.     

A study on physical and mechanical properties for soft to firm clays in Yangon area – Properties of clays deposit at the sedimentary basins in Myanmar

Recently, a great deal of foreign investment has been entered into construction of the social infrastructure of Myanmar. Many construction projects are therefore on-going, and these are especially planned in the Yangon area. While these construction booms are increasing, existing studies on the geotechnical problems in the Yangon area such as problematic soils like soft clays are limited at present. Information on soil properties has also not been shared and has been confined to individual projects. In this paper, the boring and laboratory tests carried out in the Yangon area are selected and focused upon among the tests carried out in Myanmar. Laboratory test results for clay deposits in the Yangon area are analyzed and the differences in soil properties between different sedimentary basins and sub-areas divided by the Tertiary sediment ridge that runs from north to south at the center of Yangon are clarified together with a comparison to the clays found in other countries, which have been previously investigated.     

An experimental study of energy dips for speech and music

Speech signals generally have many intervals with low energy “energy dips”. For music signals, energy dips are not always remarkable. We studied stochastic features of energy dips for speech and music signals. A certain difference was found between the signals in the length of energy dips. Also, the number of energy dips in a time window and their distribution were investigated. From this distribution, a threshold number of energy dips was estimated which provided a scheme for the discrimination of speech from music.     

Connection structures between type-I and type-II defects in neutron irradiated beta-Si3N4

High-resolution electron microscopy (HREM) observation clarified that various types of interstitial dislocations were induced into beta-Si3N4 by high-dose neutron irradiation, and two of them have been analysed and reported in our previous papers. These two defective structures are called type-I and type-II. They are interstitial dislocation loops introduced into [100] and [110] planes, respectively. In this study, it was found that some of these dislocation loops connected with each other. The connections of type-I-L2-type-II-B and type-I-R2-type-II-A dislocations were observed by HREM. Tetrahedral arrangements of the connected parts are proposed, based on the simplified crystal structure model of beta-Si3N4. In addition, a new type of defect, type-III, was found. Type-III is an interstitial dislocation loop introduced into [100] planes. It was also found that type-I-A and type-III dislocations connected with each other.