688 research outputs found

    Analysis of Problems in Cut Slope Survey and Design Based on Case Studies

    Get PDF
    In construction of roads or large residential complexes, the formation of large scale cut slopes is inevitable due to the large proportion of mountains in Korea. The problems involving the slope stability has emerged as a major concern. Inaccurate subsurface exploration can result in slope failure during or after the construction, thereby increasing the construction cost and delaying the construction duration. This study reviews problems involving the cut slope survey methods, design criteria, and examining the collapse mechanisms through various case studies. This study suggests the optimum survey methods and design criteria based on the possible failure mechanisms

    Electromagnet Weight Reduction in a Magnetic Levitation System for Contactless Delivery Applications

    Get PDF
    This paper presents an optimum design of a lightweight vehicle levitation electromagnet, which also provides a passive guide force in a magnetic levitation system for contactless delivery applications. The split alignment of C-shaped electromagnets about C-shaped rails has a bad effect on the lateral deviation force, therefore, no-split positioning of electromagnets is better for lateral performance. This is verified by simulations and experiments. This paper presents a statistically optimized design with a high number of the design variables to reduce the weight of the electromagnet under the constraint of normal force using response surface methodology (RSM) and the kriging interpolation method. 2D and 3D magnetostatic analysis of the electromagnet are performed using ANSYS. The most effective design variables are extracted by a Pareto chart. The most desirable set is determined and the influence of each design variable on the objective function can be obtained. The generalized reduced gradient (GRG) algorithm is adopted in the kriging model. This paper’s procedure is validated by a comparison between experimental and calculation results, which shows that the predicted performance of the electromagnet designed by RSM is in good agreement with the simulation results

    Expression of Keratin 10 in Rat Organ Surface Primo-vascular Tissues

    Get PDF
    AbstractThe primo-vascular system is described as the anatomical structure corresponding to acupuncture meridians and has been identified in several tissues in the body, but its detailed anatomy and physiology are not well understood. Recently, the presence of keratin 10 (Krt10) in primo-vascular tissue was reported, but this finding has not yet been confirmed. In this study, we compared Krt10 expression in primo-vascular tissues located on the surface of rat abdominal organs with Krt10 expression on blood and lymphatic vessels. Krt10 protein (approximately 56.5 kDa) was evaluated by western blot analysis and immunohistochemistry. Krt10 (IR) in the primo-node was visualized as patchy spots around each cell or as a follicle-like structure containing a group of cells. Krt10 IR was also identified in vascular and lymphatic tissues, but its distribution was diffuse over the extracellular matrix of the vessels. Thus Krt10 protein was expressed in all three tissues tested, but the expression pattern of Krt10 in primo-vascular tissue differed from those of blood and lymphatic vascular tissues, suggesting that structural and the regulatory roles of Krt10 in primo-vascular system are different from those in blood and lymphatic vessels

    Analysis of different tumor volume thresholds of insignificant prostate cancer and their implications for active surveillance patient selection and monitoring

    Get PDF
    PurposeWe compared oncological outcomes according to tumor volume (TV) thresholds defining both classical and updated insignificant prostate cancer (IPC), since the TV threshold can be used as clinical parameter for active surveillance.MethodsBetween 2001 and 2012, we retrospectively analyzed 331 organ-confined prostate cancer patients who had preoperative Gleason score 6, preoperative PSA under 10 ng/mL and pathologic TV less than 1.3 mL. Among them, 81 of 331 (24.5%) had Gleason grade 4/5 disease postoperatively. Patients were stratified into two groups: (1) TV less than 0.5 mL, using the classical definition; and (2) TV between 0.5 mL and 1.3 mL, using the range of updated definition. We compared biochemical recurrence (BCR)-free survival and identified independent predictors of BCR in each group.ResultsGroup 2 had more Gleason grade 4/5 disease than group 1 (P<0.001). On multivariate analysis, Gleason grade 4/5 disease was not associated with BCR in group 1 (P=0.132). However, it was an independent predictor for BCR in group 2 (P=0.042). BCR-free survival were not significantly different according to the presence of Gleason grade 4/5 disease in group 1 (P=0.115). However, in group 2, it was significantly different according to the presence of Gleason grade 4/5 disease (P=0.041).ConclusionsAlthough the TV thresholds of the two definitions of IPC vary only slightly, this difference was enough to result in different clinical course if Gleason grade 4/5 disease was present. Therefore, the updated IPC TV threshold should be carefully applied as clinical parameter for active surveillance

    High glucose induces MCP-1 expression partly via tyrosine kinase–AP-1 pathway in peritoneal mesothelial cells

    Get PDF
    High glucose induces MCP-1 expression partly via tyrosine kinase–AP-1 pathway in peritoneal mesothelial cells.BackgroundHigh glucose in peritoneal dialysis solutions has been implicated in the pathogenesis of peritoneal fibrosis in chronic ambulatory peritoneal dialysis (CAPD) patients. However, the mechanisms are not very clear. Peritoneal macrophages seem to participate in the process of peritoneal fibrosis and monocyte chemoattractant protein-1 (MCP-1) plays a key role in the recruitment of monocytes toward the peritoneal cavity. However, little is known about the effect of high glucose on MCP-1 expression and its signal transduction pathway in human peritoneal mesothelial cells.MethodsMesothelial cells were cultured with glucose (5 to 100 mmol/L) or mannitol chronically for up to seven days. MCP-1 expression of mRNA and protein was measured by Northern blot analysis and enzyme-linked immunosorbent assay (ELISA). Chemotactic activity of high-glucose–conditioned culture supernatant was measured by chemotactic assay. To examine the roles of the transcription factors activator protein-1 (AP-1) and nuclear factor-κB (NF-κB), electrophoretic mobility shift assay (EMSA) was performed.ResultsGlucose induced MCP-1 mRNA expression in a time- and dose-dependent manner. MCP-1 protein in cell culture supernant was also increased. Equivalent concentrations of mannitol had no significant effect. High-glucose–conditioned supernatant possessed an increased chemotactic activity for monocytes, which was neutralized by anti–MCP-1 antibody. EMSA revealed that glucose increased the AP-1 binding activity in a time- and dose-dependent manner, but not NF-κB. Curcumin, an inhibitor of AP-1, dose-dependently suppressed the induction of MCP-1 mRNA by high glucose. Tyrosine kinase inhibitors such as genistein (12.5 to 50 μmol/L) and herbimycin A (0.1 to 1 μmol/L) inhibited the high-glucose–induced MCP-1 mRNA expression in a dose-dependent manner, and also suppressed the high-glucose–induced AP-1 binding activity.ConclusionsHigh glucose induced mesothelial MCP-1 expression partly via the tyrosine kinase-AP-1 pathway

    Effects of HMGB-1 Overexpression on Cell-Cycle Progression in MCF-7 Cells

    Get PDF
    High mobility group-1 (HMGB-1) enhances the DNA interactions and possesses a transcriptional activation potential for several families of sequence-specific transcriptional activators. In order to examine the effect of HMGB-1 on the cell cycle progression in MCF-7 cells, the HMGB-1 expression vector was transfected into synchronized MCF-7 cells, and the effect of HMGB-1 overexpression on the cell cycle was examined. The HMGB-1 protein level in the transfected cells increased 4.87-fold compared to the non-transfected cells. There were few changes in the cell cycle phase distribution after HMGB-1 overexpression in the MCF-7 cells. Following the estrogen treatment, the cell cycle progressed in both the HMGB-1 overexpressed MCF-7 and the mock-treated cells. However, a larger proportion of HMGB-1 overexpressing MCF-7 cells progressed to the either S or G2 phase than the mock-treated cells. The mRNA levels of the cell cycle regulators changed after being treated with estrogen in both the HMGB-1 overexpressing MCF-7 and the mock-treated cells, but the changes in the expression level of the cell cycle regulator genes were more prominent in the HMGB-1 overexpressing MCF-7 cells than in the mock-treated cells. In conclusion, HMGB-1 overexpression itself does not alter the MCF-7 cell cycle progression, but the addition of estrogen to the HMGB-1 overexpressing MCF-7 cells appears to accelerate the cell cycle progression

    High-intensity Focused Ultrasound Ablation of Soft-tissue Tumors and Assessment of Treatment Response with Multiparametric Magnetic Resonance Imaging: Preliminary Study Using Rabbit VX2 Tumor Model

    Get PDF
    BackgroundHigh-intensity focused ultrasound (HIFU) is an emerging technique for noninvasive ablative treatment. However, HIFU has rarely been performed for the treatment of soft-tissue tumors. Thus, we aimed to assess the feasibility and safety of performing extracorporeal HIFU for the treatment of soft-tissue tumor. The treatment response was assessed using functional magnetic resonance imaging (MRI) techniques.Materials and methodsIn the rabbit VX2 intramuscular tumor model, HIFU was performed using an extracorporeal HIFU device (YDME FEP-BY02) by varying the electric power from 50 to 400 W, with the other parameters being fixed. The HIFU beam was insonated to one layer of focal spots having a depth of 8 mm. The degree of ablation was evaluated by histological examination and functional MRI techniques including dynamic contrast-enhanced MRI (DCE-MRI) and apparent diffusion coefficient (ADC) map. The presence of skin burn was also evaluated.ResultsApplying HIFU with an electric power of 200 W discretely produced the ablation zone without skin burn as planned before treatment (maximal depth: 8–9 mm), which shows the suitability of using HIFU (with 200 W electric power) for the treatment of soft-tissue tumors. By contrast, HIFU with an electric power of 100 W produced an ill-marginated ablation zone with internal residual tumor foci, and HIFU with 300–400 W produced ablation zones with a maximum depth of 13–24 mm, which far exceeded the planned depth and caused skin burn. Perfusion maps of DCE-MRI demonstrated the devascularized ablation zone more conspicuously than conventional contrast-enhanced T1-weighted images, and ADC map demonstrated the surrounding edema or granulation tissue better than conventional T2-weighted images.ConclusionExtracorporeal HIFU treatment for soft-tissue tumor may be a feasible approach with adjustment of input energy level. For post-treatment assessment, functional MRI techniques including DCE-MRI and ADC map may be useful and complementary to conventional MRI
    • …
    corecore