EFFECTS OF MO, CR, AND V ADDITIONS ON TENSILE AND CHARPY IMPACT PROPERTIES OF API X80 PIPELINE STEELS

In this study, four API X80 pipeline steels were fabricated by varying Mo, Cr, and V additions, and their microstructures and crystallographic orientations were analyzed to investigate the effects of their alloying compositions on tensile properties and Charpy impact properties. Because additions of Mo and V promoted the formation of fine acicular ferrite (AF) and granular bainite (GB) while prohibiting the formation of coarse GB, they increased the strength and upper-shelf energy (USE) and decreased the energy transition temperature (ETT). The addition of Cr promoted the formation of coarse GB and hard secondary phases, thereby leading to an increased effective grain size, ETT, and strength, and a decreased USE. The addition of V resulted in a higher strength, a higher USE, a smaller effective grain size, and a lower ETT, because it promoted the formation of fine and homogeneous of AF and GB. The steel that contains 0.3 wt pct Mo and 0.06 wt pct V without Cr had the highest USE and the lowest ETT, because its microstructure was composed of fine AF and GB while its maintained excellent tensile properties.X1126sciescopu

Risk Factors of Emergence Agitation in Adults Undergoing General Anesthesia for Nasal Surgery

ObjectivesTo identify the incidence and the risk factors of emergence agitation in adults undergoing general anesthesia for nasal surgery.MethodsWe retrospectively examined 792 patients aged ≥18 years who underwent general anesthesia for elective nasal surgery between July 2012 and August 2013. Patients in the postanesthesia care unit with a Richmond Agitation Sedation Scale≥+1 at any time were considered to have emergence agitation.ResultsThe overall incidence of emergence agitation is 22.2%. From multivariate regression analysis, the following six variables were found to be significantly associated with emergence agitation (P<0.05): younger age, recent smoking, sevoflurane anesthesia, postoperative pain on the numerical rating scale (NRS)≥5, presence of a tracheal tube, and presence of a urinary catheter. Presence of a tracheal tube was the greatest risk factor, increasing the risk of developing emergence agitation by approximately fivefold (odds ratio, 5.448; 95% confidence interval, 2.973 to 9.982). Younger age was also a strong risk factor (odds ratio, 0.975 for each 1-year increase; 95% confidence interval, 0.964 to 0.987). Current smoking, sevoflurane anesthesia, postoperative pain of NRS≥5, and the presence of a urinary catheter nearly doubled the risk of emergence agitation.ConclusionEmergence agitation following general anesthesia is a common complication in adult nasal surgery patients. To reduce the occurrence and consequences of agitation episodes, elimination of the associated risk factors is necessary, especially in at-risk patients

Efficacy of Anticholinergics for Chronic Prostatitis/Chronic Pelvic Pain Syndrome in Young and Middle-Aged Patients: A Single-Blinded, Prospective, Multi-Center Study

Purpose Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) exhibits variable lower urinary tract symptoms (LUTS). The aim of this study was to evaluate the incidence of LUTS and the efficacy of an anticholinergic agent in young and middle-aged CP/CPPS patients. Methods Ninety-six men with CP/CPPS were randomly assigned in a single-blind fashion and received either ciprofloxacin (group 1, 49 patients) or ciprofloxacin and solifenacin (5 mg/day; group 2, 47 patients) for 8 weeks. The National Institutes of Health chronic prostatitis symptom index (NIH-CPSI), the International Prostate Symptom Score (IPSS), and the International Index of Erectile Function-5 (IIEF-5) were used to grade the patients' symptoms and the quality of life impact at the start of the study, and at 4 and 8 weeks from the initiation of the study. Results There was no significant difference between groups 1 and 2 with respect to age, duration of disease, or sub-domains of the IPSS, NIH-CPSI, or IIEF-5 at baseline. Of these patients, 67.4% had LUTS. Statistically significant differences were determined via the NIH-CPSI for total score and the pain and urinary domain scores. Statistically significant differences were determined via the IPSS for total score and the storage domain score. The total score of the IIEF-5 increased, but the change was not significant. There was no statistically significant difference in residual urine. Conclusions Many CP/CPPS patients had LUTS. Solifenacin in CP/CPPS demonstrated improvements in the NIH-CPSI and the IPSS total score and storage score. Storage factors significantly improved via the NIH-CPSI and IPSS assessments in the solifenacin treatment group

The Role of Epigenetic Changes in the Progression of Alcoholic Steatohepatitis

Alcoholic steatohepatitis (ASH) is a progression hepatitis with severe fatty liver and its mortality rate for 30-days in patients are over 30%. Additionally, ASH is well known for one-fifth all alcoholic related liver diseases in the world. Excessive chronic alcohol consumption is one of the most common causes of the progression of ASH and is associated with poor prognosis and liver failure. Alcohol abuse dysregulates the lipid homeostasis and causes oxidative stress and inflammation in the liver. Consequently, metabolic pathways stimulating hepatic accumulation of excessive lipid droplets are induced. Recently, many studies have indicated a link between ASH and epigenetic changes, showing differential expression of alcohol-induced epigenetic genes in the liver. However, the specific mechanisms underlying the pathogenesis of ASH remain elusive. Thus, we here summarize the current knowledge about the roles of epigenetics in lipogenesis, inflammation, and apoptosis in the context of ASH pathophysiology. Especially, we highlight the latest findings on the roles of Sirtuins, a conserved family of class-III histone deacetylases, in ASH. Additionally, we discuss the involvement of DNA methylation, histone modifications, and miRNAs in ASH as well as the ongoing efforts for the clinical translation of the findings in ASH-related epigenetic changes

The Paradoxical Protective Effect of Liver Steatosis on Severity and Functional Outcome of Ischemic Stroke

Background: There is very limited information on the relationship between non-alcoholic fatty liver disease (NAFLD) and the severity or functional outcomes of ischemic stroke or transient ischemic stroke (TIA). We investigated the correlation between NAFLD and stroke outcomes.Methods: NAFLD was assessed in 321 patients with first-ever acute ischemic stroke or TIA, who underwent transient elastography from January 2014 to December 2014. The association of liver steatosis with stroke severity, assessed using the National Institute of Health Stroke Scale (NIHSS), was investigated using robust regression analysis. We also compared the functional outcome at 90 days according to the presence or burden of liver steatosis.Results: NAFLD was observed in 206 (64.2%) patients. Patients with NAFLD had less severe stroke (median NIHSS score 2 vs. 3, P = 0.012) and more favorable functional outcome at 90 days (85.3 vs. 70.5, P = 0.004). Patients with NAFLD were likely to have a 23.3% lower [95% confidence interval (CI), −39.2 to −3.2%, P = 0.026] NIHSS score and a 2.5-fold higher (95% CI, 1.08–5.67, P = 0.033) possibility of favorable functional outcome in multivariate analysis.Conclusions: Our study shows that a higher burden of liver steatosis seems to be associated with less severe stroke and better functional outcome after ischemic stroke or TIA

User Equilibrium-Based Location Model of Rapid Charging Stations for Electric Vehicles with Batteries That Have Different States of Charge

A model was developed for the location of rapid charging stations for electric vehicles (EVs) in urban areas, taking into account the batteries' state of charge and users' charging and traveling behaviors. EVs are one means of preparing for the energy crisis and of reducing greenhouse gas emissions. To help relieve range anxiety, an adequate number of EV charging stations must be constructed. Rapid charging stations are needed in urban areas because there is inadequate space for slow-charging equipment. The objective function of the model is to minimize EVs' travel fail distance and the total travel time of the entire network when the link flow is determined by a user equilibrium assignment. The remaining fuel range (RFR) at the origin node is assumed to follow a probabilistic distribution to reflect users' charging behavior or technical development. The results indicate that the model described in this paper can identify locations for charging stations by using a probabilistic distribution function for the RFR. The location model, which was developed on the basis of user equilibrium assigmnent, is likely to consider the congested traffic conditions of urban areas, to avoid locating charging stations where they could cause additional traffic congestion. The proposed model can assist decision makers in developing policies that encourage the use of EVs, and it will be useful in developing an appropriate budget for implementing the plan.OAIID:oai:osos.snu.ac.kr:snu2014-01/102/0000002383/3SEQ:3PERF_CD:SNU2014-01EVAL_ITEM_CD:102USER_ID:0000002383ADJUST_YN:YEMP_ID:A075708DEPT_CD:457CITE_RATE:.556FILENAME:lee et al(2014) ue based location model.pdfDEPT_NM:건설환경공학부SCOPUS_YN:YCONFIRM:

Monte Carlo Few-Group Constant Generation for CANDU 6 Core Analysis

The current neutronics design methodology of CANDU-PHWRs based on the two-step calculations requires determining not only homogenized two-group constants for ordinary fuel bundle lattice cells by the WIMS-AECL lattice cell code but also incremental two-group constants arising from the penetration of control devices into the fuel bundle cells by a supercell analysis code like MULTICELL or DRAGON. As an alternative way to generate the two-group constants necessary for the CANDU-PHWR core analysis, this paper proposes utilizing a B1 theory augmented Monte Carlo (MC) few-group constant generation method (B1 MC method) which has been devised for the PWR fuel assembly analysis method. To examine the applicability of the B1 MC method for the CANDU 6 core analysis, the fuel bundle cell and supercell calculations are performed using it to obtain the two-group constants. By showing that the two-group constants from the B1 MC method agree well with those from WIMS-AECL and that core neutronics calculations for hypothetical CANDU 6 cores by a deterministic diffusion theory code SCAN with B1 MC method generated two-group constants also agree well with whole core MC analyses, it is concluded that the B1 MC method is well qualified for both fuel bundle cell and supercell analyses