Numerical prediction of cavitation and pressure fluctuation around marine propeller

The applicability of numerical prediction method for cavitation around marine propeller was studied. A commercial CFD code was applied for computation of 10 different propellers. The computed cavitation patterns and pressure fluctuations were compared with model test. As the result, it s shown that this method can be used for the prediction of the behavior of sheet cavitation and the pressure fluctuation of the 1st order of blade frequency component.http://deepblue.lib.umich.edu/bitstream/2027.42/84315/1/CAV2009-final141.pd

Phase transitions of an intrinsic curvature model on dynamically triangulated spherical surfaces with point boundaries

An intrinsic curvature model is investigated using the canonical Monte Carlo simulations on dynamically triangulated spherical surfaces of size upto N=4842 with two fixed-vertices separated by the distance 2L. We found a first-order transition at finite curvature coefficient \alpha, and moreover that the order of the transition remains unchanged even when L is enlarged such that the surfaces become sufficiently oblong. This is in sharp contrast to the known results of the same model on tethered surfaces, where the transition weakens to a second-order one as L is increased. The phase transition of the model in this paper separates the smooth phase from the crumpled phase. The surfaces become string-like between two point-boundaries in the crumpled phase. On the contrary, we can see a spherical lump on the oblong surfaces in the smooth phase. The string tension was calculated and was found to have a jump at the transition point. The value of \sigma is independent of L in the smooth phase, while it increases with increasing L in the crumpled phase. This behavior of \sigma is consistent with the observed scaling relation \sigma \sim (2L/N)^\nu, where \nu\simeq 0 in the smooth phase, and \nu=0.93\pm 0.14 in the crumpled phase. We should note that a possibility of a continuous transition is not completely eliminated.Comment: 15 pages with 10 figure

Diffuse Pulmonary Ossification in Fibrosing Interstitial Lung Diseases: Prevalence and Associations

Purpose: To investigate the prevalence of diffuse pulmonary ossification (DPO) in patients with fibrosing interstitial lung disease (ILD) and determine whether there are differences among the types of ILDs. // Materials and Methods: Institutional review board approval was given and patient consent was not required for this study. The study population comprised 892 consecutive patients with fibrosing ILD, including 456 patients with idiopathic pulmonary fibrosis (IPF) (men, 366; women, 90; median age, 72 years [range, 38–93 years]), 244 with nonspecific interstitial pneumonia (men, 79; women, 165; median age, 60.5 years [range, 23–86 years]), and 192 with chronic hypersensitivity pneumonitis (men, 76; women, 116; median age, 66 years [range, 35–88 years]). Pulmonary ossifications were recorded when nodules (<4 mm diameter) were identified on bone window images (width, 2500 HU; level, 500 HU). DPO was defined as 10 or more bilateral nodular ossifications (definition 1) or as one or more lobes with five or more bilateral nodular ossifications (definition 2). Relationships among pulmonary ossification and parenchymal patterns, clinical parameters, and multidisciplinary team diagnoses were examined. The prevalence of DPO was compared with the χ2 statistic or Fisher exact test, and multivariate analysis was performed with logistic regression. // Results: In the whole population, the prevalence of DPO was 166 (18.6%) and 106 (11.9%) of 892 patients according to definitions 1 and 2, respectively. The prevalence of DPO (definition 1) was significantly higher in patients with IPF (28.5%) than in those without IPF (8.3%, P < .001). Nine of 192 (4.7%) had chronic hypersensitivity pneumonitis (P < .001), and 27 of 244 (11.1%) had nonspecific interstitial pneumonia (P < .001). At multivariate analysis, DPO according to definition 1 was an independent predictor of IPF diagnosis (P < .001) and male sex (P = .003). Coarseness of fibrosing ILD (P = .011) and IPF diagnosis (P = .016) were independently associated with pulmonary ossification profusion. // Conclusion: DPO is common in patients with fibrosing ILD and is significantly more prevalent in patients with IPF than in those with other fibrosing ILDs, and thus, computed tomographic signs of DPO may be helpful for diagnosis of IPF

Comparative study between wear of uncoated and TiAlN-coated carbide tools in milling of Ti6Al4V

As is recognized widely, tool wear is a major problem in the machining of difficult-to-cut titanium alloys. Therefore, it is of significant interest and importance to understand and determine quantitatively and qualitatively tool wear evolution and the underlying wear mechanisms. The main aim of this paper is to investigate and analyse wear, wear mechanisms and surface and chip generation of uncoated and TiAlN-coated carbide tools in a dry milling of Ti6Al4V alloys. The quantitative flank wear and roughness were measured and recorded. Optical and scanning electron microscopy (SEM) observations of the tool cutting edge, machined surface and chips were conducted. The results show that the TiAlN-coated tool exhibits an approximately 44% longer tool life than the uncoated tool at a cutting distance of 16 m. A more regular progressive abrasion between the flank face of the tool and the workpiece is found to be the underlying wear mechanism. The TiAlN-coated tool generates a smooth machined surface with 31% lower roughness than the uncoated tool. As is expected, both tools generate serrated chips. However, the burnt chips with blue color are noticed for the uncoated tool as the cutting continues further. The results are shown to be consistent with observation of other researchers, and further imply that coated tools with appropriate combinations of cutting parameters would be able to increase the tool life in cutting of titanium alloys

Moderately differentiated colorectal adenocarcinoma as a lymph node metastatic phenotype: comparison with well differentiated counterparts

<p>Abstract</p> <p>Background</p> <p>The differences between the metastatic property of moderately (Mod) and well (Wel) differentiated colorectal adenocarcinoma remain unclear. Since Mod is unable to form complete acini, therefore an epithelial-mesenchymal transition (EMT) can occur in that structure. Herein, we hypothesized that Mod metastasizes more easily than the Wel counterparts.</p> <p>Methods</p> <p>The medical records of 283 consecutive patients with Mod (n = 71) or Wel (n = 212) who underwent surgery were reviewed between January 1, 2001, and December 31, 2003, for actual 5-year overall survival. We examined the differences between the clinicopathological characteristics of the Mod and the Wel groups.</p> <p>Results</p> <p>The lymph node involvement (<it>p </it>< 0.0001), lymphatic permeation, venous permeation, depth of invasion, liver metastasis, and carcinomatous peritonitis were significantly higher in the Mod group in comparison to the Wel group. The independent risk factors by a logistic regression analysis for lymph node involvement were as follows: lymphatic permeation, liver metastasis, and Mod (<it>p </it>= 0.0291, Relative Risk of 1.991: 95% Confidence Interval: 1.073-3.697). A Kaplan-Meier survival curve showed that Mod had a trend towards a poor survival (<it>p </it>= 0.0517).</p> <p>Conclusion</p> <p>Mod metastasizes to the lymph nodes more easily in comparison to Wel. Therefore, patients with Mod may be considered the existence of lymph node involvement.</p

Alcohol consumption and cigarette smoking in relation to high frequency of p53 protein accumulation in oesophageal squamous cell carcinoma in the Japanese

We investigated levels of p53 protein expression in Japanese patients with oesophageal squamous cell carcinoma. A significantly larger proportion of heavy alcohol drinkers and cigarette smokers was evident in the p53-positive group. The combination of drinking and smoking was associated with a high frequency of p53 protein accumulation. © 2000 Cancer Research Campaig

Serial automated quantitative CT analysis in idiopathic pulmonary fibrosis: functional correlations and comparison with changes in visual CT scores

OBJECTIVES: To determine whether computer-based CT quantitation of change can improve on visual change quantification of parenchymal features in IPF. METHODS: Sixty-six IPF patients with serial CT imaging (6-24 months apart) had CT features scored visually and with a computer software tool: ground glass opacity, reticulation and honeycombing (all three variables summed as interstitial lung disease extent [ILD]) and emphysema. Pulmonary vessel volume (PVV) was estimated by computer only. Relationships between changes in CT features and forced vital capacity (FVC) were examined using univariate and multivariate linear regression analyses. RESULTS: On univariate analysis, changes in computer variables demonstrated stronger linkages to FVC change than changes in visual scores (CALIPER ILD:R2=0.53, p<0.0001; Visual ILD:R2=0.16, p=0.001). PVV increase correlated most strongly with relative FVC change (R2=0.57). When PVV constituents (vessel size and location) were examined, an increase in middle zone vessels linked most strongly to FVC decline (R2=0.57) and was independent of baseline disease severity (characterised by CT fibrosis extent, FVC, or DLco). CONCLUSIONS: An increase in PVV, specifically an increase in middle zone lung vessels, was the strongest CT determinant of FVC decline in IPF and was independent of baseline disease severity. KEY POINTS: • Computer analysis improves on visual CT scoring in evaluating deterioration on CT • Increasing pulmonary vessel volume is the strongest CT predictor of functional deterioration • Increasing pulmonary vessel volume predicts functional decline independent of baseline disease severity

Monitoring activity-dependent bulk endocytosis with the genetically-encoded reporter VAMP4-pHluorin

AbstractBackgroundActivity-dependent bulk endocytosis (ADBE) is the dominant mode of synaptic vesicle (SV) endocytosis during intense neuronal activity, implicating it as a major contributor to presynaptic plasticity under these stimulation conditions. However methods to monitor this endocytosis mode have been limited to either morphological or optical observation of the uptake of large fluid phase markers.New methodWe present here a method to monitor ADBE using the genetically-encoded reporter VAMP4-pHluorin in primary neuronal cultures.ResultsIndividual nerve terminals expressing VAMP4-pHluorin display either an increase or decrease in fluorescence after stimulation terminates. The decrease in fluorescence reflects the slow acidification of large bulk endosomes to which VAMP4-pHluorin is selectively recruited. Use of VAMP4-pHluorin during sequential high frequency stimuli revealed that all nerve terminals perform ADBE, but not all do so in response to a single stimulus. VAMP4-pHluorin also displays a rapid activity-dependent decrease in fluorescence during high frequency stimulation, a response which is particularly prominent when expressed in hippocampal neurons. The molecular mechanism responsible for this decrease is still unclear, but is not due to loss of VAMP4-pHluorin from the nerve terminal.Comparison with existing methodsThis method allows the selective reporting of ADBE for the first time, when compared to previous approaches using markers of fluid phase uptake.ConclusionsThe development of VAMP4-pHluorin as a selective genetically-encoded reporter of ADBE increases the palette of approaches used to monitor this endocytosis mode both in vitro and in vivo