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Interacting nature between impurity hydrogen atoms and vacancy-type defects in single crystal ZnO was investigated by means of positron annihilation lifetime spectroscopy. In order to clarify the observation of their thermal behavior, the sample was implanted with 1 H + using an electrostatic accelerator. After the implantation, the positron lifetime became shorter, which suggests that the hydrogen atoms were captured by zinc vacancies ( V Zn ) to form vacancy-hydrogen complexes ( V Zn +  n H). The complexes decompose by heat treatment: most of the hydrogen atoms gradually dissociate from V Zn +  n H in the temperature range 393–773 K. It was also suggested that large vacancy clusters were formed by the agglomeration of smaller clusters during the process of stepwise isochronal annealings at temperatures from 773 to 1073 K, and their decomposition took place at 1173–1373 K. Temperature-dependent thermal behaviors of hydrogen atoms and vacancy-type defects in ZnO are discussed. [ABSTRACT FROM AUTHOR]

Abstract The aims of this study were to evaluate the efficacy of partial parotidectomy using retrograde dissection of the marginal mandibular branch of the facial nerve for benign tumours of the parotid gland and to establish the indications for its use. We examined 106 consecutive patients with previously untreated benign tumours in the lower portion of the parotid gland who were treated by parotidectomy. The first group (anterograde group, n=52) consisted of those who had standard anterograde parotidectomy. The remaining patients, who underwent retrograde parotidectomy, were further divided into two groups: those in whom the upper edge of the tumour was located below the mastoid tip (below mastoid group, n=46) or those in whom it was above the mastoid tip (above mastoid group, n=8). The operating time was significantly shorter in the below mastoid group (141.2, 127.5, and 98.1 minutes, respectively) as was intraoperative blood loss (41.1, 53.0, and 24.4 ml, respectively), compared with the other two groups. There was a higher incidence of facial nerve dysfunction in the above mastoid group postoperatively (4/8) than in the other two groups. The results suggested that the presence of a tumour of any size located below the mastoid tip is a good indication for parotidectomy using retrograde dissection of the marginal mandibular branch of the facial nerve. [ABSTRACT FROM AUTHOR]

We employed X-ray diffraction using collimated X-rays to quantitatively evaluate the local hydrogen concentration behavior in metals. Hydrogen concentrating around a crack tip significantly accelerates crack propagation, i.e., hydrogen embrittlement. In order to clarify the mechanism leading to this, the local hydrogen concentration behavior, i.e., at a crack tip, was evaluated by numerical analysis and experimental measurements. Although thermal desorption analysis can be used to evaluate the total hydrogen content in metals, it cannot be applied to local areas. Microprint methods, which use chemical reactions between hydrogen and coated elements cannot quantitatively evaluate the hydrogen content. The present study takes account of hydrogen-induced strain, and X-ray diffraction in a confined area was employed to detect variations in lattice spacing before and after hydrogen charging. Using X-ray diffraction applied to a small area, we demonstrate that the hydrogen concentrates in the vicinity of the crack, i.e., at the elastic–plastic boundary. [ABSTRACT FROM AUTHOR]

Oral surgery can be difficult in patients with chorea-like dyskinesia, which is common in those on long-term levodopa medication for Parkinson’s disease, and we know of no conclusive evidence to indicate whether conscious sedation with midazolam is effective in such cases. We report a patient in whom levodopa-induced chorea-like dyskinesia disappeared when midazolam was given intravenously for conscious sedation. [ABSTRACT FROM AUTHOR]

Abstract: Resection of the superior or lateral wall of the cancer-affected oropharynx can often lead to disturbed nasal breathing, dysphagia, and dysarthria. The authors used the Gehanno method to reconstruct these surgical defects and achieved favourable functional recovery soon after surgery. The present study was undertaken to analyze the long-term outcome and usefulness of this method. Reconstruction was carried out using the Gehanno method in 36 patients during the 10-year period between 1997 and 2007. Both short-term and long-term evaluations of the postoperative function were performed in 12 of the 36 cases. The postoperative function was favourably maintained in all 12 cases, but gradual deterioration was noted in some cases in which the forearm flap had been used for reconstruction. Conventionally, the forearm flap is considered suitable for the reconstruction of complex structures such as the oropharynx because of its excellent flexibility. The results suggest that if the forearm flap is used for reconstruction using the Gehanno method, the surrounding tissue is likely to undergo change over time. The rectus abdominis myocutaneous flap should be considered as the first-choice flap for reconstruction using the Gehanno method. [Copyright &y& Elsevier]

Summary: Objectives: CCN family 2/connective tissue growth factor (CCN2/CTGF) is an atypical growth factor for growth plate chondrocytes. It plays an important role in their proliferation and differentiation in vitro, but does not stimulate hypertrophy or calcification of articular chondrocytes. We herein report for the first time that CCN2/CTGF promotes growth and differentiation of auricular chondrocytes and maintains their molecular phenotype in vitro and in vivo. Methods: Auricular chondrocytes were isolated from rabbit auricular cartilage by trypsin–collagenase treatment, and treated with human recombinant CCN2/CTGF or infected with adenovirus harboring the ccn2/ctgf gene. Cell proliferation was measured by [3H] thymidine incorporation and MTS assay, and changes in gene expression of auricular chondrocyte markers were monitored by real-time polymerase chain reaction, Northern hybridization, and histological analysis. For in vivo studies, auricular chondrocytes were cultured as pellets and implanted subcutaneously after treatment of recombinant human CCN2/CTGF. Ectopically formed cartilage was subjected to histological analysis. Cell death was monitored by in situ TUNEL analysis. Results: CCN2/CTGF stimulated proliferation, differentiation and synthesis of elastin and proteoglycans of rabbit primary auricular chondrocytes in a dose-dependent manner. CCN2/CTGF caused a 2.5-fold increase in the expression of elastin in comparison to the control, resulting in enhanced deposition of elastin fibers in a monolayer culture of auricular chondrocytes. Mineralization was not induced; in contrast, CCN2/CTGF stimulated expression of matrix gla protein which is known to impair mineralization. Furthermore, pretreatment of pellets of auricular chondrocytes with CCN2/CTGF and subcutaneous implantation significantly enhanced the growth of ectopic auricular cartilage pieces expressing phenotypic markers of auricular chondrocytes including type II and X collagen. Notably, chondrocyte apoptosis was impaired by CCN2/CTGF. Conclusions: These findings show that CCN2/CTGF may be a suitable agent for promoting differentiation and growth of auricular chondrocytes, while preventing mineralization and apoptosis, and suggests that CCN2/CTGF may be useful for the repair or reconstruction of elastic cartilage. [Copyright &y& Elsevier]

BACKGROUND: The rates of spontaneous remission and relapse of autoimmune pancreatitis (AIP) are not known. OBJECTIVE: To study the clinicopathologic factors predictive of remission and relapse in cases of AIP. DESIGN: Retrospective study. PATIENTS: Of the 20 patients with AIP, complete response to steroid therapy was recognized in 12 patients, and the remaining 8 patients improved without steroid therapy. Seven patients experienced a relapse. RESULTS: Patients who were seronegative for immunoglobulin (Ig) G4, had no obstructive jaundice, no diabetes mellitus, no swelling of the duodenal papilla, negative staining of the duodenal papilla for IgG4, and focal pancreatic swelling showed a greater tendency toward spontaneous remission (P < .05). The results of multivariate analysis revealed that negative staining of the duodenal papilla for IgG4 was the only independent predictor of spontaneous remission of AIP (odds ratio [OR] 1.395, P = .0304). Seropositivity for IgG4, diffuse swelling of the pancreas, and the presence of stricture in the lower part of the bile duct were significantly associated with a relapse of AIP (P < .05) according to the results of univariate analysis, whereas the results of multivariate analysis revealed only diffuse pancreatic swelling as an independent predictor of a relapse of AIP (OR 26.197, P = .0331). CONCLUSIONS: Endoscopic findings are of useful prognostic value, because patients with AIP and with negative staining of the duodenal papilla for IgG4 appeared to have a higher frequency of remission without steroid therapy. Patients with AIP and with diffuse pancreatic swelling were found to be at an increased risk of relapse after the initial steroid administration. [ABSTRACT FROM AUTHOR]

Abstract: A direct numerical simulation (DNS) of aerodynamic sounds is performed by using a compressible CFD scheme with node-by-node finite elements. Although the computational simulations of aerodynamic sounds generated from three-dimensional objects with complex boundary shapes are required in various industrial applications, such simulations involve a lot of difficulties regarding instability in numerical schemes and enormous computational costs. In this paper, the present authors have combined the C-CUP (CIP-Combined Unified Procedure, CIP: Constrained Interpolation Profile) method and the CIVA (Cubic Interpolation with Volume/Area Coordinates) method with the Free Mesh Method (FMM) in order to achieve efficient simulation of aerodynamic sounds using unstructured computational grids of finite elements on parallel computers. As a numerical example, the edge tone is successfully computed using the present method with parallel computing with Hitachi SR8000 supercomputer. [Copyright &y& Elsevier]

An oxygen molecular sheet beam was generated using the nozzle beam method, focused with multi-pole magnets, and was then used as the target of a non-destructive beam-profile monitor. The method used for focusing the sheet beam with multi-pole magnets is based on the fact that an oxygen molecule has a magnetic moment as large as two Bohr magnetons and a spin of 1. Using focusing magnets, the density of an oxygen sheet beam at the median plane increased up to about twice compared with the value obtained without focusing magnets. The principle of focusing and the focusing multi-pole magnets have been studied. [Copyright &y& Elsevier]

Recently we found that some nucleosides such as inosine or adenosine inhibited alpha-glucosidase from rat intestine. The aim of this study was to determine whether these nucleosides are sucrase inhibitors in humans as well as rats. Blood glucose and insulin responses were examined in 23 healthy volunteers (18 males and 5 females) administered sucrose with inosine and 8 (males) administered sucrose with adenosine. The initial increase in plasma glucose and serum insulin concentrations at 30 min after loading sucrose (50 g) alone were significantly reduced by co-administration of inosine (2.5 and 1.0 g) or adenosine (2.5 g). The total increases in the areas under the plasma glucose and serum insulin concentration curves for 3 h after administration of the same amount of sucrose with inosine were also significantly less than those when the volunteers were administered sucrose alone. These results in humans agree with the findings obtained in our previous studies in rats. These nucleosides may be used as one of the components of artificial sweeteners when mixed with sucrose and may be useful as food additives to suppress increases in blood glucose and insulin. [ABSTRACT FROM AUTHOR]