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Deals with a study which investigated the electrical and structural properties for the fluorinated silicon oxide (SiO...:F):carbon films in comparison with those for the undoped SiO...:F films. Experimental procedure; Results and discussion.

Presents a study which examined the bonding properties of glow discharge polycrystalline and amorphous silicon carbide films. Correlation of the growth mechanism and the effects of hydrogen dilution with changes in bonding configuration; Experimental procedure; Results and discussion.

The size of cellulose microfibril (CMF) bundles varies to interact with glucomannan/galactoglucomannan (GM/GGM). Arabino-4-O-methylglucuronoxylan (AGX) bonded CMF bundles coated with GM/GGM also have important roles in elaborating the distance between these components. Since the precise roles of GM/GGM and AGX are not clear, the elution analysis to evaluate the strength of the interaction between the cell wall were tried. Earlywood (EW) and latewood (LW) were separated in a Japanese cedar. The chemical components of cellulose, hemicellulose including GM/GGM and AGX, and lignin were almost the same in EW and LW. Slight differences in GM/GGM, the side-chain substitution in AGX and the ionic bond characteristics of glucuronic acid side chains were observed. Based on measurements of GM/GGM and AGX adhering to CMFs, there were more hemicelluloses forming strong hydrogen bonds in LW than in EW. The results showed that the highly assembled hemicellulose in LW produced a strong cell wall framework. [ABSTRACT FROM AUTHOR]

Abstract: We exposed crystalline Si (C-Si) substrates to a NH3 plasma by the method of plasma enhanced chemical vapor deposition (PECVD) and the Si substrates were nitrided at a nitridation temperature, T n, between 300 and 600°C. The nitrided layers were grown directly on n-type C-Si substrates with high resistivity for measurements of electron resonance (ESR) and Fourier transform infrared (FTIR) absorption. The intensity of the N–H IR bending band increased with increasing T n up to 450°C, and then decreased again with a further increasing in T n. We found a strong correlation between the change in the ESR spin density, N s, and that in the N–H bending intensity, which was obtained from the spectral intensity at around 1200cm−1. Furthermore, incorporation of N atoms in amorphous Si x N y layers may improve the structural property at T n =450°C for various insulating applications. In addition, we found that the atomic densities and/or composition of a-Si x N y may decrease the BHF etch rate. [Copyright &y& Elsevier]

Abstract: Static corrosion tests of various steels were conducted in oxygen-saturated liquid Pb–Bi eutectic at 450°C and 550°C for 3000h to study the effects of temperature and alloying elements on corrosion behavior in liquid Pb–Bi. Corrosion depth decreases at 450°C with increasing Cr content in steels regardless of ferritic/martensitic steels or austenitic steels. Appreciable dissolution of Ni and Cr does not occur in the three austenitic steels at 450°C. Corrosion depth of ferritic/martensitic steels also decreases at 550°C with increasing Cr content in steels whereas corrosion depth of austenitic steels, JPCA and 316SS becomes larger due to ferritization caused by dissolution of Ni at 550°C than that of ferritic/martensitic steels. An austenitic stainless steel containing about 5%Si exhibits fine corrosion resistance at 550°C because the protective Si oxide film is formed and prevents dissolution of Ni and Cr. [Copyright &y& Elsevier]

Abstract: Corrosion tests were performed in oxygen-saturated liquid Pb–Bi at 450°C and 550°C in a pot for 3000h for Al-surface-treated steels containing various levels of Cr contents. The Al surface treatments were achieved using a gas diffusion method and a melt dipping method. Al2O3, FeAl2 and AlCr2 produced by the gas diffusion method exhibited corrosion resistance to liquid Pb–Bi, while the surface layer produced by the melt dipping method suffered a severe corrosion attack. Fe4Al13 and Fe2Al5 produced by the melt dipping method disappeared during the corrosion test at 550°C and only FeAl remained. [Copyright &y& Elsevier]

The corrosion properties of three austenitic steels with different Si contents were studied under oxygen-saturated liquid Pb–Bi condition for 3000 h. The three austenitic steels did not exhibit appreciable dissolution of Ni and Cr at 450 °C. At 550 °C, the thick ferrite layer produced by dissolution of Ni and Cr was found in JPCA and 316SS with low Si contents while the protective oxide film composed of Si and O was formed on 18Cr–20Ni–5Si steel and prevented dissolution of Ni and Cr. [Copyright &y& Elsevier]

Corrosion tests of austenitic stainless tube were done under flowing Pb–Bi conditions for 3000 h at 450 °C. Specimens were 316SS produced as a tubing form with 13.8 mm outer diameter, 2 mm thickness and 40 cm length. During operation, maximum temperature, temperature difference and flow velocity of Pb–Bi at the specimen were kept at 450, 50 °C, and 1 m/s, respectively. After the test, specimen and components of the loop were cut and examined by optical microscope, SEM, EDX, WDX and X-ray diffraction. Pb–Bi adhered on the surface of the specimen even after Pb–Bi was drained out to the storage tank from the circulating loop. Results differed from a stagnant corrosion test in that the specimen surface became rough and the corrosion rate was maximally 0.1 mm/3000 h. Mass transfer from the high temperature to the lower temperature area was observed: crystals of Fe–Cr were found on the tube surface in the low-temperature region. The sizes of crystals varied from 0.1 to 0.2 mm. The depositing crystals were ferrite grains and the chemical composition ratio (mass%) of Fe to Cr was 9:1. [Copyright &y& Elsevier]

Circulating immune complexes (CIC) were frequently observed in patients with idiopathic thrombocytopenic purpura (ITP). To analyse the pathogenic role of CIC, we studied the correlation between the disease activity and the CIC level, and whether platelet antigens were involved in CIC from ITP sera. Elevated CIC levels, measured by C1q. anti-C3 and spermatozoa micro-enzyme-linked immunosorbent assay, were found in 37%, 54% and 52% of the patients, respectively. However, there were no significant correlations (r = -011, -003 and -0.04, respectively) between the platelet count and the CIC level. Platelet antigens in CIC were detected with rabbit anti-human platelet serum. The CIC from 18%, 25% and 25%, respectively, of ITP sera contained platelet antigens, but the CIC from only 3%. 9% and 6% of SLE sera and from 3%, 2% and 5% of the sera of alloimmunized patients, respectively, contained these antigens. There were significant correlations (r = 0.51, 0.80 and 0.65, respectively) between the amount of platelet antigens and the CIC level in ITP sera. However, there were no correlations (r = -0.26, -0.29 and 0-08, respectively) between the platelet count and the amount of platelet antigens in the CIC. We detected platelet antigens in CIC from ITP sera, but surmise that these CIC perhaps do not play an important role in platelet destruction. [ABSTRACT FROM AUTHOR]

Describes a chemical process developed for the polishing of the surface of gadolinium-silicon oxide (GSO) scintillator crystals. Reasons for polishing the surface of the scintillator; Uses of GSO scintillators; Importance of manufacturing cost in surface polishing; Details on an etching experiment which was conducted; Efficiency of the scintillator.

Investigates the vibrational absorption of silicon hydride in amorphous SiO[sub x]:H film based on the charge-transfer model. Examination of absorption profiles on the basis of random-bonding model; Use of Sanderson's electronegativity to study the length of hydride bonds; Details on the peak wave numbers for the four hydrogen-silicon bonding units.

Aim: To investigate whether contrast-enhanced (CE)-magnetic resonance imaging (MRI) improves identification of implantation site of ectopic pregnancy.Materials and Methods: This retrospective study enrolled 63 patients in whom implantation sites had been confirmed at histopathology. Two expert radiologists for gynaecological imaging and two inexpert radiologists independently reviewed non-CE MRI and a combination of non-CE and CE-MRI (non-CE+CE-MRI), then determined implantation site with a confidence level. The following MRI features were also evaluated: extrauterine gestational sac (GS)-like structure (shape, signal intensities at T1-weighted imaging [WI], T2WI, and diffusion-weighted imaging [DWI], presence of the three rings appearance, and distinct low intensity areas at T2WI, presence of tree or dot-like components, degree of contrast enhancement), fallopian tube (dilatation, dilatation with haematoma, degree of contrast enhancement, enhanced components within the tube), and ascites. These findings were compared for non-CE and non-CE+CE-MRI data, and for expert and inexpert groups.Results: The expert group identified implantation sites correctly in 58/63 (92%) cases for non-CE and non-CE+CE-MRI. In the inexpert group, the correct identification was improved from 54/63 (86%) using non-CE MRI to 58/63 (92%) using non-CE+CE-MRI, but was not significant (p=0.29). In comparison between non-CE and non-CE+CE-MRI, dilation of the fallopian tubes was observed more frequently (p=0.004) and the confidence level was elevated significantly in the non-CE+CE-MRI (p<0.0001) in the inexpert group. Intergroup comparison revealed that confidence level was significantly higher in the expert group than in the inexpert group using non-CE MRI (p<0.0001), although the difference was not significant at non-CE+CE MRI (p=0.49).Conclusion: CE-MRI did not significantly improve correct identification of ectopic pregnancy implantation sites, although the addition of contrast enhancement did enable inexpert radiologists to diagnose confidently. [ABSTRACT FROM AUTHOR]

Amorphous SiO2 (a-SiO2) layers were prepared using a thermal oxidation method. The SiO2 layers were nitrided at a temperature Tn between 450 and 650 °C utilizing a plasma generation system, in which the layers before the nitridation were simultaneously grown on two different n-type crystalline Si substrates, one having a high resistivity for electron-spin resonance (ESR) and Fourier transform infrared absorption measurements and another having a low resistivity for current–voltage (I–V) measurement. We found the breakdown strength, estimated based on the I–V characteristics, increased with increasing Tn until 550 °C, but the annealing at a further high Tn caused also a decrease in the breakdown strength. We found a strong correlation between the changes in the I–V characteristics and those in the bonding properties, and this correlation was also discussed in connection with the change in the ESR properties for the a-SiOxNy layers. Furthermore, incorporation of N atoms into SiO2 layers at Tn=550 °C was suggested to improve the structural properties and the electrical properties. [ABSTRACT FROM AUTHOR]

Presents a study that prepared undoped polycrystalline silicon films on a fused quartz substrate as a function of the radio frequency power and deposition temperature by a plasma-enhanced chemical vapor deposition method. Details of the experiment; Results and discussion; Conclusion.

Presents information on a study which discussed changes of the structural and electrical properties brought about by an in situ plasma supply during growth of undoped and boron doped low-pressure chemical vapor deposition poly-silicon film and plasma-enhanced chemical vapor deposition films. Structural property; Effects of plasma supply on improvement of the surface roughness; Electrical property.

Presents information on a study which analyzed the effects brought about by the addition of nitrogen on the bonding properties as a function of the degree of crystallization for boron-doped microcrystalline into amorphous silicon nitride[subx]:hydrogen films. Investigation of the degree of crystallization by means of x-ray diffraction; Vibrational-absorption profiles; Electrical and optical properties.

Presents a study of the crystal structure and the bonding configurations of Si[sub1-x]C[subx] films prepared by plasma-enhanced chemical vapor deposition. Description of cubic silicon carbide; X-ray diffraction pattern on the films; Classification of films according to the composition.

Study Design: A report on 2 cases of subarachnoid pleural fistula (SAPF) treated with noninvasive positive pressure ventilation (NPPV).Objective: To highlight the efficacy of NPPV in patients with SAPF.Summary Of Background Data: SAPF is a rare but distressing type of cerebrospinal fluid leakage. It is known to be a complication of anterior thoracic spine surgery. The pressure gradient between the subarachnoid space and the pleural cavity maintains the cerebrospinal fluid leakage and precludes the spontaneous closure of the dura. Surgical interventions such as primary repair, patch grafts, muscle flaps, and omental flaps have been advocated. Only limited reports were found with reference to NPPV applied to SAPF.Methods: Two patients, a 45-year-old woman and a 39-year-old woman, underwent anterior thoracic spine surgery to treat thoracic myelopathy caused by ossification of the posterior longitudinal ligament. After surgery, they developed SAPF due to perforation of the dura during surgery. Placement of thoracostomy tubes and subarachnoid drains had no effect and an NPPV device was applied.Results: During application of the NPPV device, 14 days in the first patient and 5 days in the second patient, the raised intrapleural pressure obstructed the fluid leakage and successfully treated the fistula. No recurrence of SAPF was observed after removal of the NPPV device and the patients avoided surgical interventions.Conclusion: SAPF is often resistant to conservative therapies and has been treated in an invasive manner. NPPV should be considered as an alternative before such interventions because it is effective, noninvasive, and safe. [ABSTRACT FROM AUTHOR]

Background and Purpose: The expression of voltage-dependent K(+) channels (K(v) ) 1.5 is regulated by members of the heat shock protein (Hsp) family. We examined whether the heat shock transcription factor 1 (HSF-1) and its inducer geranylgeranylacetone (GGA) could affect the expression of K(v) 1.5 channels and its anchoring protein, synapse associated protein 97 (SAP97).Experimental Approach: Transfected mouse atrial cardiomyocytes (HL-1 cells) and COS7 cells were subjected to luciferase reporter gene assay and whole-cell patch clamp. Protein and mRNA extracts were subjected to Western blot and quantitative real-time polymerase chain reaction.Key Results: Heat shock of HL-1 cells induced expression of Hsp70, HSF-1, SAP97 and K(v) 1.5 proteins. These effects were reproduced by wild-type HSF-1. Both heat shock and expression of HSF-1, but not the R71G mutant, increased the SAP97 mRNA level. Small interfering RNA (siRNA) against SAP97 abolished HSF-1-induced increase of K(v) 1.5 and SAP97 proteins. A luciferase reporter gene assay revealed that the SAP97 promoter region (from -919 to -740) that contains heat shock elements (HSEs) was required for this induction. Suppression of SIRT1 function either by nicotinamide or siRNA decreased the level of SAP97 mRNA. SIRT1 activation by resveratrol had opposing effects. A treatment of the cells with GGA increased the level of SAP97 mRNA, K(v) 1.5 proteins and I(Kur) current, which could be modified with either resveratrol or nicotinamide.Conclusions and Implications: HSF-1 induced transcription of SAP97 through SIRT1-dependent interaction with HSEs; the increase in SAP97 resulted in stabilization of K(v)1.5 channels. These effects were mimicked by GGA. [ABSTRACT FROM AUTHOR]

Abstract: The structural properties of polycrystalline silicon films, prepared by plasma enhanced chemical vapor deposition system, with different flow rates of SiH4/SiF4 mixtures at 300°C were investigated. This study indicates that the low hydrogen coverage on the growing surface, under optimum fluorine radicals, will be leaded to an improvement of crystallized area as compared with case of high hydrogen coverage surface. Moreover, the studies of the role of SiH4 and SiF4 radicals show that the SiH4 radicals are important in the nucleation and growth of grains. However, SiF4 radicals are effective in the structural change of grain boundaries regions and by this way, in the present system, establish the growth of grains under the dominant 〈110〉 direction. The stress investigation indicates that addition of high flow rate of SiF4 in amorphous film, results in the nearly stress free films. Finally, we found that the changes in g-value reflect the changes in the intrinsic compressive and tensile stress in the both polycrystalline and amorphous silicon films. [Copyright &y& Elsevier]

Abstract: The structural properties of polycrystalline silicon films, prepared by plasma enhanced chemical vapor deposition system, with different flow rates of SiH4/SiF4 mixtures at 300°C were investigated. This study indicates that the low hydrogen coverage on the growing surface, under optimum fluorine radicals, will be leaded to an improvement of crystallized area as compared with case of high hydrogen coverage surface. Moreover, the studies of the role of SiH4 and SiF4 radicals show that the SiH4 radicals are important in the nucleation and growth of grains. However, SiF4 radicals are effective in the structural change of grain boundaries regions and by this way, in the present system, establish the growth of grains under the dominant 〈110〉 direction. The stress investigation indicates that addition of high flow rate of SiF4 in amorphous film, results in the nearly stress free films. Finally, we found that the changes in g-value reflect the changes in the intrinsic compressive and tensile stress in the both polycrystalline and amorphous silicon films. [Copyright &y& Elsevier]

The supercritical water process is an attractive method for the decomposition of hazardous organic wastes and for the upgrading of low quality hydrocarbon resources. However, corrosion of reactors or heat exchangers is a major problem in industrial applications. It is important to select suitable structural materials, which are compatible with the supercritical water environment of each particular process, to ensure the long term integrity of the reactor components. The objectives of the present study were to evaluate the corrosion behaviour of candidate corrosion-resistant alloys in supercritical water environments under reducing atmospheres and to improve understanding of the corrosion mechanism. Four kinds of Ni-base alloys, Alloy 625, Alloy C-276, Ni–45Cr–1Mo (MC alloy) and Ni–19Cr–19Mo (MAT 21) and a Type 316 stainless steel were used in the present study. A parametric study was carried out to investigate the influences of environmental variables such as temperature, anion content, pH and the hydrogen partial pressure, on the corrosion rate and corrosion morphology of the alloys. A static autoclave was used in the present study. The exposure time was 50 h, the applied pressure was 25 MPa and the test temperature was 400°C. The susceptibility of the alloys to stress corrosion cracking was also evaluated by the slow constant strain rate technique. The corrosion rate of Type 316 stainless steel was always higher than that of any of the Ni-base alloys in supercritical water containing NaOH. While the weight change of Type 316 stainless steel was small in deionised water, the weight gain significantly increased with increasing NaOH concentrations. In a reducing atmosphere containing NaOH, the weight loss increased with increasing hydrogen partial pressure. In supercritical water under a reducing atmosphere containing NaOH, Ni-base alloys containing both Cr and Mo, such as Alloy C-276 and MAT 21, would be more resistant to corrosion than Ni–Cr binary alloys. Stress corrosion cracking did not occur in deionised water at 400°C/25 MPa. With 0·001 mol L-1 HCl or 0·01 mol L-1 NaOH, cracking occurred in Type 316 stainless steel. With 0·001 mol L-1 HCl or NaOH, cracking occurred in Alloy C-276. With 0·01 mol L-1 HCl or NaOH, cracking occurred in Alloy 625. The cracking susceptibility of Ni-base alloys in supercritical water containing either HCl or NaOH decreased as their Cr content increased. [ABSTRACT FROM AUTHOR]

Abstract: Plasma enhanced chemical vapor deposited polycrystalline Si films were prepared at 300°C, with varying SiF4 and/or H2 flow rates under otherwise fixed conditions. The changes in the SiF4 and/or H2 flow rates caused changes in the structural properties, defects, and the surface morphology of the Si films. The occurrence of a dominant 〈110〉 texture for film with [H2]=0sccm and under high SiF4 flow rate corresponded with low hydrogen coverage. While with an increase in the hydrogen flow rate the 〈311〉 texture becomes a predominant plan for grains growth, suggesting a reduction in the grain size for 〈110〉 texture and an increase in the nucleation rate for 〈311〉 texture. The film surface roughness investigation shows that it greatly affected the grains orientation. Finally we found that the degree of preferred orientation is an important factor in controlling the oxidation of the film and its stability. [Copyright &y& Elsevier]

Amorphous silicon oxynitride, a-SiOxNy, layers were prepared by nitridation of 7-nm thick thermally grown silicon dioxide, a-SiO2, layers on n-type crystalline Si substrates, in NH3 plasma with different temperatures (TP=300–500 °C). The compositional and structural properties for the a-SiOxNy layers were examined using current–voltage (I–V), capacitance–voltage (C–V), electron spin resonance (ESR), Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy and Fourier transform infrared measurements. We found a strong correlation between the change in the ESR spin density and that in the C–V characteristics with varying TP. These results were interpreted as indicating a change in the compressive strain. The I–V characteristics showed that the breakdown strength monotonically decreased with increasing TP. In the distribution of the constituent atoms, the AES profiles were roughly independent of TP. The changes in the 800 and 1070 cm−1 IR absorption bands were also examined based on those in the compressive strain, as well as a proposal for interpreting the ESR and C–V results. [Copyright &y& Elsevier]

Analyzes the causes of cracks in single-crystal gadolinium-silicon oxide (GSO), and studies the growth conditions of GSO. Scintillation properties of GSO crystals; History of single-crystal cerium GSO; Observations made of the GSO crystal boule; Possible causes of the cracks; How the causes of the cracks were eliminated.

In this letter, polycrystalline 3C-SiC (111) films were deposited by plasma enhanced chemical vapor deposition system at a temperature of 670 °C using a gas mixture of SiH4/CH4/H2/(CF4). The optical properties of deposited films with different feed gases and different structures were investigated. In these studies, a broad photoluminescence band was observed for films with lower crystallinity and the radiative transitions between the conduction and valance band tails were suggested as the origin of the observed peak. The band gap of these polycrystalline SiC films was estimated at around 2.10 eV. [ABSTRACT FROM AUTHOR]

Amorphous silicon oxynitride (a-SiN[sub x]O[sub y]) films were deposited at 300 °C using a plasma-enhanced chemical vapor deposition technique, which was carried out with variation in the nitrogen-flow-rate ratio (R[sub N]) and the oxygen-flow-rate ratio (R[sub O]) to control the nitrogen and oxygen contents, x and y, respectively. Changes in the structural properties and the characteristics of defects in the films were examined based on the electron spin resonance as well as infrared and optical absorption measurements. An increase in either R[sub N] or R[sub O] was found to decrease the deposition rate, the density of charged or neutral defects, and the randomness of the bonding network. Thus the incorporation of O or N atoms into Si nitride or Si oxide films, respectively, acts to improve the qualities of the insulating films. Furthermore, the nearest N and O atom neighboring to a Si site would be randomly bonded to the Si atom. Our results also showed that N-related dangling bonds, other than so-called K centers, are favorably created after annealing, but that the formation of Si-O bonds in the films makes the formation of such defects difficult. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Investigates the bonding configuration and defects in amorphous SiN[sub x]:H films. Maximum of the slope in the Urbach form of the absorption coefficient; Examination of the random-bonding model including hydrogen atoms.

Polycrystalline silicon (poly-Si) films were prepared on a fused quartz substrate at 700 °C by low-pressure chemical vapor deposition (LPCVD) and plasma-enhanced CVD (PECVD) using the same fabrication system. Poly-Si films with a strong <100> and <110> preferential orientation (P.O.) are obtained by changing the rf power for generating the plasma under the same preparation condition. The surface of the PECVD films with dominant <100> and <110> textures is very smooth in contrast with that of LPCVD films. These textures are maintained after thermal oxidation at 1000 °C, and the degree of P.O. and the grain size increase. [ABSTRACT FROM AUTHOR]

Amorphous SiNx:H films were prepared by rf glow discharge (GD) of SiH4-N2-H2 mixtures at 300 °C using a new decomposition technique. The optical gap Eg increases slowly with the ratio N2/SiH4 up to a critical gap Egc of 2.5–3.0 eV, and then rapidly increases up to 5.3 eV. The spin density Ns from electron spin resonance of Si dangling bonds increases with N2/SiH4 until Eg reaches Egc. Above Egc, Ns rapidly decreases in contrast with that of conventional GD films, but in similarity to pyrolytic films. The slope B in Tauc equation for optical absorption corresponds well with Ns. [ABSTRACT FROM AUTHOR]

Microcrystalline SiNx:H films were prepared by rf glow discharge of SiH4-B2H6-N2-H2 mixtures with the gas volume ratio of B2H6/SiH4=4.5×10-3. The volume fraction of the crystalline phase and the crystallite size decrease with an increase in N content x, and the films were amorphous at x above 0.2. The dark conductivity σd decreases and the optical gap Eg increases with x. The gap-state density is lowest at x near 0.2, where σd∼10-2–10-3/Ω cm (the activation energy is 0.1 eV) and Eg∼1.9 eV. These electrical properties are improved as compared with those for B-doped amorphous SiNx:H. [ABSTRACT FROM AUTHOR]

Reports on the relationship between the stress and bonding properties of amorphous SiN[subx]:H films. Deposition of amorphous SiN[subx]:H films on single crystal silicon; Significance of amorphous SiN[subx]:H films deposited by plasma-enhanced chemical vapor deposition; Densities of the SiH and NH bonds.

Presents a study that investigated the effects of the incorporation of phosphorus and nitrogen impurities on the electrical and structural properties of polysilicon carbide thin films. Methodology; Examination of the resistivity and spin density of the samples; Analysis of the crystallinity of the samples.

Provides information on a study examining the 200-nm-thick polycrystalline silicon films were deposited by changing the deposition temperature (Td = 150-750...C). Methodology used to conduct the study; Incorporation of O and N atoms depending on Td; Findings of the study.

Provides information on an experiment investigating the structure, optical absorption and photoluminescence (PL) properties of SiOx films subjected to thermal annealing at 750-1100...C. Methodology used to conduct the experiment; Information on Optical absorption; Results of the experiment.

Discusses a study which investigated the characteristics of defects in amorphous silicon nitride films subjected to ultraviolet illumination and anneal treatments. Background on the materials; Description of the experimental setup; Findings.

Investigates the structure of polycrystalline silicon (Si) films prepared from amorphus silicon deposited using disilane. Factor attributed to the increase in the transmission electron microscopy size; Effects of post-hydrogenation on the poly-Si films; Description of structural properties.

Studies the structure and grain boundary defects of glow-discharge polycrystalline silicon films deposited using disilane. Deposition of poly-silicon films using monosilane; Significance of polycrystalline silicon films as a material for thin-film transistors; Examination of the morphology by means of x-ray diffraction using a diffractometer.

Presents a study which investigated the stress in plasma-enhanced chemical vapor deposition hydrogenated amorphous silicon nitrogen[subx] films. Experimental details; Results and discussion; Conclusion.

Abstract: We previously demonstrated that the peptidergic neurotransmitter pituitary adenylate cyclase-activating polypeptide (PACAP) affects the autonomic system and contributes to the control of metabolic and cardiovascular functions. Previous studies have demonstrated the importance of centrally-mediated sympathetic effects of leptin for obesity-related hypertension. Here we tested whether PACAP signaling in the brain is implicated in leptin-induced sympathetic excitation and appetite suppression. In anesthetized mice, intracerebroventricular (ICV) pre-treatment with PACAP6-38, an antagonist of the PACAP receptors (PAC1-R and VPAC2), inhibited the increase in white adipose tissue sympathetic nerve activity (WAT-SNA) produced by ICV leptin (2μg). In contrast, leptin-induced stimulation of renal sympathetic nerve activity (RSNA) was not affected by ICV pre-treatment with PACAP6-38. Moreover, in PACAP-deficient (Adcyap1−/−) mice, ICV leptin-induced WAT-SNA increase was impaired, whereas RSNA response was preserved. The reductions in food intake and body weight evoked by ICV leptin were attenuated in Adcyap1−/− mice. Our data suggest that hypothalamic PACAP signaling plays a key role in the control by leptin of feeding behavior and lipocatabolic sympathetic outflow, but spares the renal sympathetic traffic. [Copyright &y& Elsevier]

BACKGROUND: : Patients treated with propranolol, a nonselective [beta]-adrenoceptor antagonist, have increased incidence and severity of anaphylaxis. We determined whether [beta]1- or [beta]2-adrenoceptor antagonist modulated pulmonary vasoconstriction and bronchoconstriction in rat anaphylactic hypotension. METHODS: : Anesthetized ovalbumin-sensitized male Sprague-Dawley rats were randomly allocated to the following pretreatment groups (n = 7/group): (1) sensitized control (nonpretreatment), (2) propranolol, (3) the selective [beta]2-adrenoceptor antagonist ICI 118,551, (4) the selective [beta]1-adrenoceptor antagonist atenolol, and (5) adrenalectomy. Shock was induced by an intravenous injection of the antigen. Mean arterial pressure, pulmonary arterial pressure, left atrial pressure, central venous pressure, portal venous pressure, airway pressure, and aortic blood flow were continuously measured. RESULTS: : In either sensitized control or atenolol-pretreated rats, mean arterial pressure and aortic blood flow decreased substantially, whereas pulmonary arterial pressure and airway pressure did not increase soon after antigen injection. In contrast, in rats pretreated with either propranolol, ICI 118,551, or adrenalectomy, airway pressure significantly increased by 14 cm H2O, and pulmonary arterial pressure by 7.5 mmHg after antigen injection. At 2.5 min after antigen injection, the plasma concentration of epinephrine increased 14-fold in the sensitized rats except for the adrenalectomy group. Portal venous pressure after antigen injection increased by 16 mmHg similarly in all sensitized rats. All of the sensitized control group and two of the atenolol group were alive for 60 min after antigen injection, whereas all rats of the propranolol, ICI 118,551, and adrenalectomy groups died within 50 min after antigen injection. CONCLUSIONS: : The pulmonary vasoconstrictive and bronchoconstrictive responses to systemic anaphylaxis were weakened via [beta]2-adrenoceptor activation by epinephrine endogenously released from the adrenal gland in the anesthetized Sprague-Dawley rats. [ABSTRACT FROM AUTHOR]

The feasibility for the lead-bismuth--cooled accelerator-driven system (ADS) to transmute minor actinides partitioned from high-level radioactive waste is discussed. Since lead-bismuth will cause considerable corrosion and erosion effects at high temperature, the fuel-clad temperature must be kept as low as possible. Moreover, the most critical issue of the ADS design is the engineering viability of the high-power spallation target and the beam window. The thermal-hydraulic and structural analysis was carried out for both the fuel assembly and the beam window. In addition to the analysis in steady state, the transient behaviors were also studied during typical transient and unprotected accidents. The results showed that engineering viability is reasonably achievable in the nominal operation. For the beam trip, which will be the most frequent transient, the number of events to cause the failure of the beam window is estimated as more than 105. For safety aspects of the ADS during unprotected accidents, the estimated results showed that unprotected loss of flow would cause the most significant problem, if the beam operation was kept. Therefore, high reliability of the beam shutdown is required for the ADS safety. [ABSTRACT FROM AUTHOR]

We developed Lu0 .4 Gd1 .6 SiO5 (LGSO) crystal as a new scintillator for medical imaging applications. The size of the LGSO ingot obtained for this investigation was approximately 60 mm in diameter and 170 mm in length. The as-grown crystal was yellow in color. To eliminate the tint, the crystal was annealed in pure N2 atmosphere after the growth. As a result, the LGSO became colorless with uniform and large light output which is about 2.0 times that of GSO. [ABSTRACT FROM AUTHOR]

Aim: The purpose of this study was to determine whether anaphylactic hypotension in rabbits is accompanied by hepatic venoconstriction, and the effects of anaphylaxis on hepatic segmental vascular resistances and liver weight in isolated perfused rabbit livers. Methods: The rabbits were sensitized by subcutaneous injection of antigen of 2.5 mg ovalbumin with complete Freund's adjuvant three times at 1 week interval. One week after sensitization, anaphylaxis was induced by an injection of 2.5 mg ovalbumin into the jugular vein of pentobarbital anaesthetized rabbits or the perfusate of rabbit livers perfused via the portal vein at a constant flow. Using the double occlusion technique to estimate the hepatic sinusoidal pressure, pre- ( Rpre) and post-sinusoidal ( Rpost) resistances were calculated for the isolated perfused livers. Results: An antigen injection into the sensitized rabbits caused not only a decrease in systemic arterial pressure from 79 ± 2 to 40 ± 4 mmHg, but also an increase in portal venous pressure ( Ppv) from 9.5 ± 2.2 to 24.1 ± 3.9 cmH2O. Portal hypertension persisted for 8 min after the antigen injection. An injection of antigen into the perfusate caused a marked increase in Ppv from 5.4 ± 0.1 to 28.6 ± 2.4 cmH2O at 6 min, but only a slight increase in double occlusion pressure from 2.2 ± 0.2 to 3.8 ± 0.2 cmH2O, resulting in a selective increase in Rpret rather than Rpost. Concomitant with the hepatic pre-sinusoidal constriction, liver weight loss occurred. Conclusion: Anaphylactic hypotension in rabbits is accompanied by hepatic venoconstriction which is characterized by pre-sinusoidal contraction. [ABSTRACT FROM AUTHOR]

The emission spectra for X-ray and UV excitation, decay curve for emission above 460 nm under γ-ray excitation, and energy spectrum by using avalanche photodiode (APD) for excitation with 137Cs γ-rays have been measured for Lu0.4Gd1.6SiO5 having 2.0 mol% Ce. The emission spectrum under X-ray excitation showed two peaks around 430 and 495 nm. The excitation-emission spectrum under UV excitation also had two peaks at 425 and 510 nm for excitation wavelength of 285 and 385 nm, respectively. There was no significant difference in decay constants of emission between the longer and shorter wavelength components. Energy resolution by using an APD was 8.0% for 137Cs γ-ray excitation. [ABSTRACT FROM AUTHOR]

We present the results of a search for candidate planetary transits using the Microlensing Observations in Astrophysics-I (MOA-I) microlensing survey data in the Galactic bulge. To achieve sufficient photometric precision, the analysis was confined to a selected subset of stars on selected images. Periodicities of light curves were found with a Box fitting Least Squares (BLS) procedure. This yielded 12 candidates. The derived radii of the candidates ranged from 1.7 to 3.2 RJ, consistent with interpretations in terms of blended binaries, late M dwarfs or strongly irradiated giant planets. Follow-up spectroscopic observations would be required to identify actual planets amongst the candidates by radial velocity variations. The results confirm that microlensing surveys provide an effective means for finding candidate planetary transits. It is anticipated that the recently commissioned MOA-II telescope will provide further candidates in the future. [ABSTRACT FROM AUTHOR]

Hepatic xenotransplantation from guinea-pig to rat has not been established. This failure is partly ascribed to differences in hepatic vascular characteristics between two species. However, the differences in hepatic vascular resistance distribution and responses to vasoconstrictors are not known. The present study was designed to determine basal levels of segmental vascular resistances and the responses to histamine and noradrenaline in isolated guinea-pig and rat livers. The livers were haemoperfused (Hct 8.3%) via the portal vein at a constant flow. The sinusoidal pressure was measured by the double occlusion pressure, and was used to determine the pre- ( Rpre) and post-sinusoidal ( Rpost) resistances. There was no significant difference in basal total hepatic vascular resistance ( Rt) between two species, whereas Rpre in rat (69% of Rt) was significantly greater than that in guinea-pig (61% of Rt). The responses to noradrenaline were similar; Rpre increased in a greater magnitude than Rpost, and liver weight was reduced. However, the noradrenaline-induced increase in Rt was greater in rats than in guinea-pigs. In contrast, histamine increased predominantly Rpost over Rpre, and increased liver weight in guinea-pig, while it affected no haemodynamic variables in rat. There exist species differences in the hepatic vasculature between rat and guinea-pig. Basal pre-sinusoidal resistance in rat is greater than that in guinea-pig. Although noradrenaline predominantly contracts pre-sinusoidal vessels in both species, histamine causes predominant post-sinusoidal vasoconstriction in guinea-pig liver, while it has no vasoactive effects on rat liver. [ABSTRACT FROM AUTHOR]

Amorphous Si oxynitride (a-SiOxNy) films were deposited at 300 °C using a plasma-enhanced chemical vapor deposition technique, by varying the NH3 flow rate, [NH3], under fixed SiH4 and O2 flow rates to control the x- and y-values. The characteristics of defects were investigated vis-a&grave;-vis structural and bonding properties. These films were ‘stoichiometric’, including no or less homobonds. As [NH3] increases, the x- and y-values decreased and increased, respectively, and a relationship of 2x+3y=4.14 (±0.02) was found. With increasing [NH3], the deposition rate increased, but the defect density and the stress can be decreased. [Copyright &y& Elsevier]

Peripheral blood T cells from 40 patients with idiopathic thrombocytopenic purpura (ITP) were analysed for the presence of surface la antigens using monoclonal antibodies by indirect immunofluorescence. The percentage of la-positive (Ia &plus;) T cells was significantly increased in patients with ITP (6.8±2.9%. P<0.005) as compared with normal controls (2.3 ± 0.9%), There was an inverse correlation between the percentages of Ia+ T cells and platelet counts (r = 0.58, P<0.005)and a positive correlation between the percentage of these cells and platelet-associated IgG (PAIgG) values (r = 0.55, P<0.01), The percentage of la+ T cells was found to decrease within two weeks during therapy with high dose γ - globulin or corticosteroid. We have previously reported the presence of T cells bearing both helper/inducer (H/I) and suppressor/cytotoxic (S/C) phenotypes (double labelled cells. DI.C) in patients with ITP and an inverse correlation between the percentages of DLC and their platelet counts. In the present study, we showed that a major part of Ia+ T cells had both H/I and S/C phenotypes. We also examined the correlation between Ia+ T cells and autologous mixed lyniphocyle reaction (AMLR). A defective AMLR was demonstrated in patients with ITP. Furthermore, an inverse correlation was found between the percentages of la+ T cells and the proliferative responses to AMLR (r= --0.49, P< 0.01). These results suggest that increased circulating Ia+ T cells play a role in the abnormalities of the immunoregulatory system of ITP. especially in the regulation of autoantibody production. [ABSTRACT FROM AUTHOR]