Ductile Fracture Simulation of Full-scale Circumferential Cracked Pipes: (II) Stainless Steel

AbstractThis paper reports ductile fracture simulation of full-scale circumferentially cracked pipes using finite element (FE) damage analysis. In the structural integrity, without experimental investigations or with few ones, it is not an easy task to properly evaluate the crack initiation and crack propagation of large-scale components with a crack-like defect. Unfortunately, from an economic perspective, performing experiments of large-scale components would be consequently unfavorable. For these reasons, ductile fracture simulation using FE damage analysis to predict crack behavior is one efficient way to replace the test procedures. In order to simulate ductile tearing of large-scale cracked pipes, element-size-dependent critical damage model based on the stress-modified fracture strain model is proposed. To evaluate fracture behavior of full-scale cracked pipes, tensile and C(T) specimens are calibrated by FE analysis technique. Tensile properties and fracture toughness of stainless steel at 288oC are taken from Battelle Pipe Fracture Encyclopedia. After calibrations, simulated results of the full-scale pipes with a circumferential crack are compared with test data to validate the proposed method

Serum 25-hydroxyvitamin D levels and risk of colorectal cancer:an age-stratified analysis

Background and aims: the role of circulating 25-hydroxyvitamin D (25(OH)D) in prevention of early-onset colorectal cancer (CRC) in young adults under 50 years is uncertain. We evaluated the age-stratified associations (&lt;50 vs. ≥50 years) :circulating 25(OH)D levels and the risk of CRC in a large sample of Korean adults.Methods: our cohort study included 236,382 participants (mean [standard deviation] age, 38.0 [9.0] years) who underwent a comprehensive health examination, including measurement of serum 25(OH)D levels. Serum 25(OH)D levels were categorized as follows: &lt;10, 10–20, and ≥20 ng/mL. CRC, along with the histologic subtype, site, and invasiveness was ascertained through linkage with the national cancer registry. Cox proportional hazard models were used to estimate hazard ratios (HRs; 95% confidence intervals [CIs]) for incident CRC according to the serum 25(OH)D status, with adjustment for potential confounders.Results: during the 1,393,741 person-years of follow-up (median, 6.5 years; interquartile range, 4.5–7.5 years), 341 participants developed CRC (incidence rate, 19.2 per 105 person-years). Among young individuals aged &lt;50 years, serum 25(OH)D levels were inversely associated with the risk of incident CRC with HRs (95% CIs) of 0.61 (0.43–0.86) and 0.41 (0.27–0.63) for 25(OH)D 10-19 and ≥20 ng/mL, respectively, with respect to the reference (&lt;10 ng/mL) (p for trend &lt;0.001, time-dependent model). Significant associations were evident for adenocarcinoma, colon cancer, and invasive cancers. For those aged ≥50 years, associations were similar, although slightly attenuated compared to younger individuals. Conclusions: serum 25(OH)D levels may have beneficial associations with the risk of developing CRC for both early-onset and late-onset disease. <br/

Acute Kidney Injury due to Sodium Bromate Intoxication: A Report of Two Cases

Sodium bromate is a strong oxidant used as a neutralizing solution in hair permanents, as well as an auxiliary agent in printing and dyeing. Accidental or deliberate ingestion of bromate solution has rarely been reported in Korea. The clinical manifestations of bromate intoxication are vomiting, diarrhea, central nervous system symptoms, oliguric or non-oliguric acute kidney injury, hemolytic anemia, and deafness; most of these manifestations are reversible, with the exception of renal failure and deafness. Here, we report on two patients who demonstrated distinct clinical progressions. In the first case, a 16-year-old woman was successfully treated with hemodialysis and recovered renal function without hearing loss. However, in the second case, delayed hemodialysis resulted in persistent renal failure and hearing loss in a 77-year-old woman. This suggests that emergency therapeutic measures, including hemodialysis, should be taken as soon as possible, as the rapid removal of bromate may be essential to preventing severe intoxication and its sequelae

A Case of Laparoscopic Radical Prostatectomy for a Prostatic Stromal Tumor of Uncertain Malignant Potential

Prostatic stromal tumor of uncertain malignant potential (STUMP) is a rare neoplasm with distinctive clinical and pathological characteristics. Here we report a case of laparoscopic radical prostatectomy performed in a patient with prostatic STUMP

Applications Know Best: Performance-Driven Memory Overcommit with Ginkgo

Abstract—Memory overcommitment enables cloud providers to host more virtual machines on a single physical server, exploiting spare CPU and I/O capacity when physical memory becomes the bottleneck for virtual machine deployment. However, overcommiting memory can also cause noticeable application performance degradation. We present Ginkgo, a policy frame-work for overcomitting memory in an informed and automated fashion. By directly correlating application-level performance to memory, Ginkgo automates the redistribution of scarce memory across all virtual machines, satisfying performance and capacity constraints. Ginkgo also achieves memory gains for traditionally fixed-size Java applications by coordinating the redistribution of available memory with the activities of the Java Virtual Machine heap. When compared to a non-overcommited system, Ginkgo runs the DayTrader 2.0 and SPECWeb 2009 benchmarks with the same number of virtual machines while saving up to 73% (50 % omitting free space) of a physical server’s memory while keeping application performance degradation within 7%. I