Cavitation Erosion of Titanium Alloys

Cavitation erosion was studied for various types of titanium alloys and for Ti-6 AI-4V with various heat treatments. The erosion resistance is the highest for β type alloy and decreases in order of a+β type alloy and pure titanium (a type). The resistance is macroscopically evaluated in terms of HV^2/E (HV : Vickers hardness and E : Young's modulus), but the erosion proceeds depending on the microstructures. Heat treatments changes the microstructure of Ti-6 AI-4V drastically. Therefore, annealing at high temperature produces the large second phase and results in the accerelation of the erosion depth, in spite of low mass loss rate

Comparison of Cavitation Erosion between Cavitating Jet and Vibratory Methods Specified in ASTM Standard

Cavitation erosion was compared between cavitating jet and vibratory methods. It was found that the erosion by cavitating jets occurs 8 to 10 times as fast as that by the vibratory, thus the cavitating jet method is effective for the acceleration test. The erosion mechanisms produced in both apparatuses are the same, judging from the time interval of bubble collapse impact loads and the shape of pits. It was concluded that erosion is evaluated by the accumulated summation of squares of impact loads, not by the accumulated volume of pits for which it is obtained from the pit on the material surface exposed to cavitation for 1-5 seconds

Adenocarcinoma in ectopic prostatic tissue at the trigone of urinary bladder

Introduction Ectopic prostatic tissue is prostatic tissue located distant from the prostate gland. Although its existence is not uncommon, the occurrence of adenocarcinoma in ectopic prostatic tissue is rare. Case presentation A 68‐year‐old man was suspected to have a nodular‐type tumor in the bladder trigone and a tumor in the prostate based on magnetic resonance imaging and cystoscopy results. Transurethral tumor resection and transrectal prostate needle biopsy revealed the coexistence of ectopic prostatic adenocarcinoma in the bladder trigone and low‐risk orthotopic prostate cancer. Four years later, the tumor evolved to intermediate‐risk prostate cancer during active surveillance, and the patient underwent prostatectomy with resection of the bladder trigone. Pathology indicated no residual ectopic prostatic tissue or adenocarcinoma at the bladder trigone. Conclusion Adenocarcinoma in ectopic prostatic tissue is very rare; however, when found, the possibility of concurrent cancer in the prostate gland should be considered

Functional adenosine triphosphate‐sensitive potassium channel is required in high‐carbohydrate diet‐induced increase in β‐cell mass

Abstract Aims/Introduction A high‐carbohydrate diet is known to increase insulin secretion and induce obesity. However, whether or not a high‐carbohydrate diet affects β‐cell mass (BCM) has been little investigated. Materials and Methods Both wild‐type (WT) mice and adenosine triphosphate‐sensitive potassium channel‐deficient (Kir6.2KO) mice were fed normal chow or high‐starch (ST) diets for 22 weeks. BCM and the numbers of islets were analyzed by immunohistochemistry, and gene expression levels in islets were investigated by quantitative real‐time reverse transcription polymerase chain reaction. MIN6‐K8 β‐cells were stimulated in solution containing various concentrations of glucose combined with nifedipine and glimepiride, and gene expression was analyzed. Results Both WT and Kir6.2KO mice fed ST showed hyperinsulinemia and body weight gain. BCM, the number of islets and the expression levels of cyclinD2 messenger ribonucleic acid were increased in WT mice fed ST compared with those in WT mice fed normal chow. In contrast, no significant difference in BCM, the number of islets or the expression levels of cyclinD2 messenger ribonucleic acid were observed between Kir6.2KO mice fed normal chow and those fed ST. Incubation of MIN6‐K8 β‐cells in high‐glucose media or with glimepiride increased cyclinD2 expression, whereas nifedipine attenuated a high‐glucose‐induced increase in cyclinD2 expression. Conclusions These results show that a high‐starch diet increases BCM in an adenosine triphosphate‐sensitive potassium channel‐dependent manner, which is mediated through upregulation of cyclinD2 expression

Brain gray matter structural network in myotonic dystrophy type 1.

This study aimed to investigate abnormalities in structural covariance network constructed from gray matter volume in myotonic dystrophy type 1 (DM1) patients by using graph theoretical analysis for further clarification of the underlying mechanisms of central nervous system involvement. Twenty-eight DM1 patients (4 childhood onset, 10 juvenile onset, 14 adult onset), excluding three cases from 31 consecutive patients who underwent magnetic resonance imaging in a certain period, and 28 age- and sex- matched healthy control subjects were included in this study. The normalized gray matter images of both groups were subjected to voxel based morphometry (VBM) and Graph Analysis Toolbox for graph theoretical analysis. VBM revealed extensive gray matter atrophy in DM1 patients, including cortical and subcortical structures. On graph theoretical analysis, there were no significant differences between DM1 and control groups in terms of the global measures of connectivity. Betweenness centrality was increased in several regions including the left fusiform gyrus, whereas it was decreased in the right striatum. The absence of significant differences between the groups in global network measurements on graph theoretical analysis is consistent with the fact that the general cognitive function is preserved in DM1 patients. In DM1 patients, increased connectivity in the left fusiform gyrus and decreased connectivity in the right striatum might be associated with impairment in face perception and theory of mind, and schizotypal-paranoid personality traits, respectively

Results of association matrices (left) and network hub nodes and edges (right).

<p>Lines indicate the edge, and spheres represent nodes. The size of the nodes is proportional to the betweenness centrality (BC). Red denotes hub nodes with BC > 2 standard deviation (SD), and green denotes BC > 1 SD. In DM 1 patients, hub nodes with BC > 2 SD were found only in the left fusiform gyrus, and hub nodes with BC > 1 SD were found in the superior and middle frontal gyrus, and superior temporal gyrus. In controls, hub nodes with BC > 2 SD were found in the right insula, putamen, superior temporal gyrus, and left fusiform gyrus, and hub nodes with BC > 1 SD were found in the middle and inferior gyrus, orbitofrontal gyrus, lingual gyrus, and rolandic operculum.</p

Regional comparison of myotonic dystrophy type 1 (DM1) group with healthy control (HC) group for betweenness centrality (BC) and clustering.

<p>Colored areas depict significant differences (at a false discovery rate of <i>p</i> < 0.05). In DM1 patients, an increased BC was found in the left fusiform gyrus, superior temporal gyrus, superior frontal gyrus, and right precuneus, and a decreased BC was found in the right caudate nucleus and putamen. Comparison of clustering showed decreased regions in the right orbitofrontal gyrus, inferior occipital gyrus, precuneus, left pallidum, and increase regions in the left supplementary motor area and superior parietal lobe.</p

Demographic and clinical data of patients with myotonic dystrophy type 1 and healthy subjects.

<p>Demographic and clinical data of patients with myotonic dystrophy type 1 and healthy subjects.</p

Results of network metrics and the p-values of AUC comparisons between DM1 and controls.

<p>No significant differences were found for measures of global and local network organization (characteristic path length, clustering, efficiency, small-worldness, assortativity, transitivity, and modularity) between DM1 patients and controls.</p