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The tensile strength of a metallic bicrystalline nanofilm containing a wedge disclination in the middle of a grain boundary (GB) terminating at the film surfaces was studied via atomistic simulations. The results show that an increase in the disclination power strengthens the film, which is contrary to intuition, if a crack initiates at one end of the terminated GB, whereas it weakens the film if a crack initiates at the disclination core. Both the strengthening and weakening demonstrate a size effect for film thickness in the range 10-20 nm, and are also significantly influenced by the GB misorientation. It is further shown that the strength can be increased to ∼80% of the theoretical strength of a defect-free film by introducing a disclination of moderate power in the GB. [ABSTRACT FROM AUTHOR]

In this paper, the problem of an edge dislocation in an elastically anisotropic dissimilar film-substrate is formulated exactly using the method of continuously distributed image dislocations. The resulting singular Cauchy integral equations are transformed into non-singular Fredholm integral equations, and the solutions are given in the form of series. The formulation and solution are greatly facilitated by the use of certain integral transforms and their iterative operations which are developed in this paper. The numerical solutions are verified by convergence study, direct checking of the governing equations and comparison with previous results. The technique of transforming singular to non-singular integral equations can be used for other physical problems. The truncated solutions can be employed as Green functions for solving problems involving cracks and dislocations and in the boundary element method. The image method can also be generalized for the analysis of multilayered composites. Numerical results for an edge dislocation located in film-substrate systems and strips demonstrate the importance of elastic anisotropy and material inhomogeneity in determining the image forces and the stress components. [ABSTRACT FROM AUTHOR]

A two-dimensional (2D) finite-difference shallow water model based on a second-order hybrid type of total variation diminishing (TVD) approximate solver with a MUSCL limiter function was developed to model flooding and inundation problems where the evolution of the drying and wetting interface is numerically challenging. Both a minimum positive depth (MPD) scheme and a non-MPD scheme were employed to handle the advancement of drying and wetting fronts. We used several model problems to verify the model, including a dam break in a slope channel, a dam break flooding over a triangular obstacle, an idealized circular dam-break, and a tide flow over a mound. Computed results agreed well with the experiment data and other numerical results available. The model was then applied to simulate the dam breaking and flooding of Hsindien Creek, Taiwan, with the detailed river basin topography. Computed flooding scenarios show reasonable flow characteristics. Though the average speed of flooding is 6-7 m s-1, which corresponds to the subcritical flow condition (Fr < 1), the local maximum speed of flooding is 14·12 m s-1, which corresponds to the supercritical flow condition {Fr ≈ 1·31). It is necessary to conduct some kind of comparison of the numerical results with measurements/experiments in further studies. Nevertheless, the model exhibits its capability to capture the essential features of dam-break flows with drying and wetting fronts. It also exhibits the potential to provide the basis for computationally efficient flood routing and warning information. [ABSTRACT FROM AUTHOR]

We recently reported that low-grade mucosa- associated lymphoid tissue lymphoma (MALToma) and diffuse large B-cell lymphoma (DLBCL) with MALToma (DLBCL[MALT]) of stomach are equally responsive to H. pylori eradication therapy (HPET) and that H. pylori-independent status is closely associated with nuclear translocation of BCL10. However, co-existing MALToma and DLBCL components of gastric DLBCL(MALT) may respond differentially to HPET and the underlying mechanism remains unclear. Tumour tissue samples from 18 patients with microdissectable co-existing MALToma and DLBCL cells were studied. The clonality of lymphoma cells was examined by polymerase chain reaction-based amplification of the CDR3 region of the IgH gene and confirmed by DNA sequence analysis. BCL10 expression was determined by immunohistochemistry. Differential response of co-existing MALToma and DLBCL to HPET was defined as complete eradication of one component while the other component remained. Five (27.8%) of the 18 patients showed different IgH gene rearrangements in the two components and three (60%) of these five patients had differential response of MALToma and DLBCL to HPET. By contrast, 13 patients showed identical IgH gene rearrangements and only one (8%) of them had differential response of the two components to HPET ( p = 0.044). Further, all four patients with differential response of MALToma and DLBCL to HPET showed nuclear expression of BCL10 in the H. pylori-independent component and cytoplasmic expression of BCL10 in the H. pylori-dependent component while the expression patterns of BCL10 were identical in both of these components in the 14 patients who had similar tumour response to HPET. We conclude that different clonality is a common reason for the differential response of co-existing MALToma and DLBCL of gastric DLBCL(MALT) to HPET and that immunohistochemical examination of BCL10 expression may help to identify the co-existence of these components. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, exact closed-form solutions for the elastic stress and strain energy density of an infinite, periodic array of inteffacial wedge disclination dipoles in a hexagonal bicrystal with arbitrary inplane e-axis orientations are derived by the method of image dislocations. These solutions are shown to be of the form of the logarithm of hyperbolic and trigonometric functions of complex parameters. The strain energy of the dipole array is also calculated by numerical integration of the density field. The results show that the stress, strain energy density and strain energy all depend significantly on the orientational and material inhomogeneities, and the importance of using an anisotropic bicrystal model over a homogeneous model for calculations is emphasized. For bicrystals with symmetric e-axis orientations, it is also shown that the strain energy of the dipole array can be a strong function of the orientations, with the maximum and minimum at specific orientations that depend on the bicrystal materials. [ABSTRACT FROM AUTHOR]

This open-label, randomized, placebo-controlled, incomplete-block, 3-period crossover pilot study investigated the effects of peroxisome proliferator-activated receptorα-andγ-agonists on biomarkers of lipid and glucose metabolism in 12 nondiabetic subjects. Plasma samples were collected before and after each 14-day treatment with placebo, fenofibrate (201 mg/d), rosiglitazone (4 mg twice daily), and combined fenofibrate (201 mg/d) plus rosiglitazone (4 mg twice daily). Except for triglycerides (P < .042) and free fatty acids (P < .074), no significant interaction was demonstrated between fenofibrate and rosiglitazone; thus, the effect due to each drug alone was evaluated (presence/absence of drug). Fenofibrate significantly (P < .050) increased lipoprotein lipase activity (35%) and decreased apolipoproteins B (13%) and C-III (20%). Rosiglitazone significantly (P < .050) decreased fasting glucose (7.3%) and increased apolipoprotein C-III (19%) and adiponectin (137%). Fenofibrate and rosiglitazone also produced effects on triglyoerides and free fatty acids, but it was not possible to determine if these effects were synergistic in nature. [ABSTRACT FROM PUBLISHER]

Polycrystalline single phase (La2-xSrx)MnO4 (1.10≤x≤1.40) samples were prepared by a citrate precursor method. They have tetragonal K2NiF4 structure with a space group of 14/mmm, increasing x, unit-cell a-axis increases and c-axis decreases, which is a result of decreasing of the Jahn-Teller effect due to the increase of the Mn(IV) ion. Spin glass state exists at low temperature and a hump observed from the susceptibility (χ) measurement is probably caused by the interactions of several magnetic phases. Among them, (La0.6Sr1.4)MnO4 has the largest magnetoresistance ratio ([ρ(H)-ρ(0)]/ρ(0)), which reaches to 78.4% at 48 K. It is not possible to obtain single phase materials with 0.60≤x≤1.00 in the heat treatment temperature range of 1000-1600°C. Impurities were easily observed under SEM and X-ray diffraction patterns. Increasing the heating period and decreasing the temperature, the amount of ABO3 perovskite phase increases. In order to extend the solubility range, of the SrO in the (La2-xSrx)MnO4, it probably needs a higher temperature (>1600°C) and a shorter heat treatment period (<1 h). [ABSTRACT FROM AUTHOR]

Presents information on a study which analyzed a sector crack in a three-dimensional Voronoi polycrystal with microstructural stresses. Generation of three-dimensional Voronoi polycrystal; Microstructural stress estimation; Numerical results; Conclusions.

Keywords:hepatic aneurysm; portal vein thrombosis; systemic lupus erythematosus; uraemia [ABSTRACT FROM PUBLISHER]

Background It has been suggested that p53 plays an important part in gastric carcinogenesis but the data remain inconclusive. Methods Alteration of the tumour suppressor gene p53 was prospectively investigated by immunohistochemistry in 168 primary gastric cancers. Results Positive staining, indicative of gene mutations, was detected in 34 tumours (20·2 per cent). No correlation was observed between expression of p53 and various clinicopathological factors, including age, sex, tumour site, gross type, tumour size, depth of invasion, lymph node metastases, distant metastases, and tumour node metastasis stage. However, p53 overexpression was different between intestinal and diffuse type gastric cancer. Survival analysis revealed a significant survival disadvantage of p53 expression in diffuse type gastric cancer (P=0·039) but not in the intestinal type. Multivariate analysis of all 168 patients revealed that independent predictors of recurrent disease included age, invasion depth and nodal involvement but not p53 expression. Conclusion The presence of p53 overexpression may identify a subset of more aggressive tumours with a poor prognosis in diffuse type gastric cancer. [ABSTRACT FROM AUTHOR]

To develop immunogene therapy targeting minimal residual hematopoietic tumor cells in patients, we transduced murine GM-CSF or CD80 gene into murine WEHI 3B myelomonocytic leukemia and EL-4 thymic lymphoma cells using retroviral vectors and evaluated their effects on inducing antitumor responses in syngeneic host mice. Subcutaneously injected GM-CSF- and CD80 gene-transduced WEHI 3B (GMCSF/WEHI/3.2 or CD80/WEHI/1.8, respectively) cells lost their original tumorigenicity in immunocompetent syngeneic mice. Results from tumor inoculation experiments using athymic nude mice suggested that the rejection of GMCSF/WEHI/3.2 in immunocompet- ent mice depended fully on T cells and that of CD80/WEHI/1.8 depended partly on T cells and partly on NK cells. In both WEHI 3B and EL-4 models, irradiated GM-CSF gene-transduced cells provided strong immunoprotection against wild-type cells, but irradiated CD80 gene- transduced cells did not. A remarkably high cooperative effect was obtained when irradiated GMCSF/EL-4 and CD80/EL-4 were inoculated together. These results suggested that the tumor vaccine effect is efficiently enhanced by GM-CSF gene transduction and CD80 gene transduction induces some protective antitumor immunity in co operation with GM-CSF gene transduction. [ABSTRACT FROM AUTHOR]

Key words: inferior vena cava thrombosis; low-molecular-weight heparin; nephrotic syndrome; pregnancy; renal vein thrombosis [ABSTRACT FROM PUBLISHER]

Background: Nitric oxide (NO) has been shown to play a role in cyclosporin (CsA) nephrotoxicity, but its mechanism of action is still unclear. As inducible NO synthase (iNOS) mRNA has been found to be expressed in rat medullary thick ascending limb (mTAL) cells, we investigated the effects of CsA on NO production in a model of mouse cultured mTAL cells. [ABSTRACT FROM PUBLISHER]

BACKGROUND: In type II diabetic patients, a better glycaemic control has been reported to slow down the progression of nephropathy. The effect of pre-dialysis glycaemic control on the long term prognosis in type II diabetics on haemodialysis is still uncertain. The purpose of this study is to evaluate the effect of glycaemic control before starting maintenance haemodialysis on the clinical outcome in type II diabetic haemodialysis patients. METHODS: One hundred and thirty-seven type II diabetics receiving regular haemodialysis in a single university hospital were enrolled. The patients were classified as either good or poor glycaemic control group according to their glycaemic control within 6 months before starting haemodialysis. Serum albumin, haematocrit, cholesterol, triglyceride, residual renal function, diabetic complications, and patient survival were analysed in both groups. RESULTS: There was no significant difference in age, gender, predialysis albumin level, cholesterol level, triglyceride level, and residual renal function between the two groups. The 1-year (94.5% vs 80.0%), 3-year (82.9% vs 58.1%), and 5-year (75.8% vs 21.8%) cumulative survival rates were lower in the poor glycaemic control group than in the good glycaemic control group (P < 0.001). The poor glycaemic control group also had more cardiovascular morbidity during the period of dialysis (P < 0.001). The increase in cardiovascular complications also accounted for the increased mortality during the course of haemodialysis. CONCLUSIONS: We conclude that poor glycaemic control before starting dialysis is a strong predictor of cardiovascular morbidity and survival for type II diabetics on haemodialysis. These results imply that better glycaemic control before dialysis might be important in improving the long-term prognosis in type II diabetics on haemodialysis. [ABSTRACT FROM PUBLISHER]

This study was carried out to develop a scoring system for the diagnosis of gastric adenocarcinoma (GAC). A total of 686 subjects, 150 patients with GAC, 182 with gastric ulcer, 127 with duodenal ulcer, and 227 subjects with negative findings, were enrolled. Analysis of the likelihood ratio (LR) showed that patients with advanced age, ulcer in the stomach, low serum levels of pepsinogen I (PGI), low PGI x gastrin values, and low PGI/gastrin ratio were likely to have GAC. Of these indicators, the serum PGI level had the greatest weight, with a LR of 7.59 for the group with a level < 30 ng/ml. A scoring system combining serum PGI level, Helicobacter pylori seropositivity, and gastric ulcer status was derived, using a logistic regression model. This scoring system was found to be better than any one-parameter criterion for diagnosing GAC after evaluation by the area under the receiver operating characteristic curve (0.84; 95% confidence interval, 0.81-0.88) or by specificity-fixed sensitivity (sensitivity 0.82 at specificity 0.72, sensitivity 0.87 at specificity 0.66, sensitivity 0.96 at specificity 0.44). This scoring system may be potentially useful as a new model for the noninvasive diagnosis of GAC in the future. [ABSTRACT FROM AUTHOR]

The influence of microtubules and F-actin on Na(+)-K(+)-Cl- cotransport was investigated in cultured cells derived from outer-medullary thick ascending limb tubules microdissected from the mouse kidney. The cultured cells contained Tamm-Horsfall protein, produced cAMP in response to dD-arginine vasopressin (dD-AVP), isoproterenol, prostaglandin E2 and forskolin (FK), and exhibited an ouabain-resistant furosemide-sensitive (Or-Fs) component of 86Rb+ influx mediated by the Na(+)-K(+)-Cl- cotransporter. Both FK and dD-AVP stimulated the Or-Fs component of Rb+ influx. Neither agent altered the tubulin and cytokeratin networks nor the shape of the tight junction using a specific anti-ZO-1 antibody. In contrast, they did induce a marked redistribution of F-actin to the periphery of the cells delineating the tight junctions. Preincubation of the cells with nocodazole, to disrupt microtubules, did not alter the FK- or dD-AVP-elicited Or-Fs Rb+ influx. In contrast, phalloidin and NBD-phallicidin, which stabilize F-actin, markedly impaired the stimulation of Na(+)-K(+)-Cl- cotransport by FK or dD-AVP, without affecting the Na(+)-K+ ATPase pumps and the rate constant of 36Cl- and 86Rb+ efflux. These results strongly suggested that cAMP-stimulated Na(+)-K(+)-Cl- cotransport is linked to F-actin in renal TAL cells. [ABSTRACT FROM AUTHOR]