Stable transverse mode oscillation in planar stripe laser with deep Zn diffusion

The guiding mechanism in a planar stripe laser with deep Zn diffusion under the lasing conditions was investigated both theoretically and experimentally. The conditions necessary to realize refractive index guiding depend on a combination of electron and hole concentrations. The lasers under refractive index guiding, whose stripe width is less than twice the diffusion length, with an adequate combination of electron and hole concentrations, show stable fundamental transverse mode oscillation up to three times the threshold current level.     

Describing head shape with surface harmonic expansions

Surface harmonic expansions are used to represent boundaries between regions of different conductivity in the human head. This facilitates calculation of the electric potential and magnetic field generated by neural current sources using discretized integral equations.     

Flagellar filament elongation can be impaired by mutations in the hook protein FlgE of Salmonella typhimurium: a possible role of the hook as a passage for the anti-sigma factor FlgM

Among motile revertants isolated from flagellar hook-deficient (flgE) mutants of Salmonella typhimurium, one produced only short flagellar filaments in L broth, despite the fact that flagellin itself has the ability to polymerize into long filaments in vitro. This pseudorevertant has an intragenic suppressor, resulting in a two-amino-acid substitution (Asp-Gln-->Ala-Arg) in the C-terminal region of the hook protein, FlgE. The flagellation of the pseudorevertant was greatly affected by the concentration of NaCl in the culture media: we observed no filaments in the absence of NaCl, short filaments in 1% NaCl and full-length filaments in 2% NaCl. Electron microscopy of osmotically shocked cells showed that the number of hook-basal bodies on cells was constant under various NaCl conditions. Furthermore, we found that the mutant hook was straight rather than curved. We monitored the cellular flagellin level of this pseudorevertant under various NaCl concentrations by immunoblotting. It was revealed that little flagellin was present under NaCl-free conditions in contrast with the ordinary amounts of flagellin present in 2% NaCl. As the expression of flagellin is regulated by competitive interaction of a sigma factor, FliA, and a corresponding anti-sigma factor, FlgM, we also observed the effect of NaCl on the secretion of FlgM. FlgM was secreted into the media in more than 1% NaCl but accumulated inside the cells in the absence of NaCl, indicating that the failure of secretion of FlgM in the absence of salt was the cause of the impaired elongation of filaments.     

Nodular glomerulosclerosis of unknown origin associated with the nephrotic syndrome

A 35-year-old male patient clinically characterized by massive proteinuria and hypertension without evidence of systemic diseases is reported. Histological investigation of renal biopsy specimens revealed extensive nodular formations in the mesangial areas in every glomerulus. Light-microscopic examination did not allow discrimination between the glomerular changes found in these specimens and the nodular glomerulosclerosis described in patients with diabetes mellitus. Electron-microscopic examination confirmed the presence of massive, nodular, mesangial expansions consisting of finely fibrillar substances without electron-dense deposits and circumferential mesangial interposition. Immunofluorescent examination showed deposition of IgG, C3, fibrinogen and kappa and lambda light chains in mesangial areas, peripheral capillary loops and a part of the nodules. Furthermore, collagen types IV, V, VI and laminin were detected in the nodules. Amyloid was not observed in these nodules. This diagnosis has not been made, and the mechanism of this nodular glomerulosclerosis remains unknown.     

A novel mutation of the GTP-cyclohydrolase I gene in a patient with hereditary progressive dystonia/dopa-responsive dystonia

PURPOSE: To evaluate re-treatment with an additional course of low-dose irradiation in patients with progressive or recurrent choroidal neovascular membranes (CNVMs). MATERIALS AND METHODS: Ten patients who had received 14 Gy of external-beam radiation therapy in seven fractions for subfoveal CNVMs were found to have recurrent or persistent neovascularization at follow-up. They received an additional 15 Gy of radiation therapy administered in five daily fractions with a standard lens-sparing technique. Before reirradiation, visual acuity ranged from 20/80 to counting fingers. The median time between radiation courses was 6.5 months (range, 2-16 months). After re-treatment, the patients were followed up with angiography and visual field testing. The median follow-up was 18.5 months (range, 12-21 months). RESULTS: Eight of 10 patients (80%) maintained their visual acuity at 1 year and three of seven (43%) at 18 months. Visual acuity was stabilized in five of the 10 patients at their last follow-up. No acute or late side effects of irradiation were noted. CONCLUSION: Additional radiation therapy in selected patients with CNVMs who have failed to benefit from previous irradiation is well tolerated and appears to stabilize the disease process in a substantial proportion of these patients.     

Phase separation and structural change accompanying the introduction of silver to arsenic trisulphide glass

Glass-glass phase separation has been observed when melts of compositions As₂S₃Ag_x (x=0.1, 0.25, 0.35, 0.4 or 0.5) were cooled slowly to 210° C and annealed at this temperature. The two glass phases produced were an Ag-rich one (approximate compositon for x=0.4, As₂S_3.4Ag_1.0) and an Ag-poor one (As₂S_2.7Ag_0.07). With increasing x value, Ag and S contents in the Ag-rich phase increased, and its composition approached that of trechmannite or smithite (AgAsS₂), whereas the Ag content of the Ag-poor phase changed little and only the S content decreased. A chemical-etching study of the phaseseparated glasses was also made.     

Adenovirus-mediated transfer of a dominant-negative H-ras suppresses neointimal formation in balloon-injured arteries in vivo

Sixteen Holstein cows in midlactation were used in a design based on a replicated 4 x 4 Latin square with the last period removed to determine the influence of particle size of beet pulp neutral detergent fiber (NDF) on its effectiveness as a replacement for alfalfa NDF. Diets were a low forage, low fiber diet [12.1 g of alfalfa NDF/100 g of dry matter (DM)], a normal forage diet (low forage plus 7.8 g of additional alfalfa NDF/100 g of DM), and two low forage diets with 5.3 g of NDF/100 g of DM from either whole or finely ground dried sugar beet pulp. Replacement of alfalfa fiber with beet pulp fiber increased milk protein yield because of the tendencies toward increased milk yield and protein concentration. However, milk fat concentration and yield were unaffected. The addition of beet pulp fiber, either whole or ground, to the basal low forage, low fiber diet did not affect yields of milk, protein, or fat, but milk protein concentration tended to be lower for cows fed the beet pulp diets than for cows fed the basal diet. Reducing the particle size of beet pulp increased DM intake but did not affect any of the milk yield measurements. Particle size reduction of beet pulp did not reduce its effectiveness as a fiber source as measured by changes in milk fat content.     

Catalytic removal of sodium sulfide from aqueous solutions and application to wastewater treatment

The activities of the catalysts for sodium sulfide oxidation in aqueous solutions were examined for the systems of hydroquinone, hydroquinone-ferric chloride, and hydroquinone-ferric chloride-ammonium peroxydisulfate. These catalyst systems are active. In calculating the volume of air needed for the complete removal of sodium sulfide in all of the experimental runs, the air requirement were found to be about 40, 15, and 8 times larger than the theoretical ones, corresponding to the runs without catalyst, hydroquinone-ferric chloride-system, and hydroquinone-ferric chloride-ammonium peroxydisulfate-system, respectively. Good results were obtained with preservation of the catalytic activity of these systems and their application to wastewater treatment.     

Electrochemical solar cell based on a sprayed CdS film photoanode

Electrochemical studies of the CdS film deposited onto a transparent conductive SnO₂-coated glass slide by chemical spray deposition were performed in aqueous polysulphide solutions and the output characteristics of the electrochemical photocell (sprayed CdS film/polysulphide electrolyte/Pt) were measured. It was proved to be possible to construct a regenerative photocell free from the light losses through the polysulphide solution path by illuminating the CdS film anode through the SnO₂-coated glass. Quantum yield and the maximum energy conversion efficiency of this photocell for monochromatic excitation of 480 nm were about 8% and 0.5%, respectively. It is concluded that the poorer quantum yield of this photocell employing CdS film than that of a photocell employing single crystal CdS can be attributed to the existence of lattice imperfections in the film.