Parameter Identification of the Lagrangian-averaged Vorticity Deviation Vortex Detection Method Through the Investigation of Fluid Flow Around Solid Bodies

The main focus of the current paper is the detection of vortices in fluid flow around a circular cylinder and a square cylinder, with an emphasis on the identification of the parameters used for vortex detection. The authors aim to enhance the practicality of an existing vortex detection method (Lagrangian-averaged vorticity deviation) by providing recommendations for the settings of the vortex detection parameters. The simulations were carried out using ANSYS Workbench 2022 R2, encompassing Reynolds numbers between 12 and 140, and angles of incidence from 0° to 45°. The vortex detection was performed using MATLAB R2020b. The paper provides a comprehensive description of the parameters involved in the detection process and their significance, as well as the implementation of the parameter identification. The study results in the determination of the suggested parameter ranges, and a comparative analysis of different vortex detection methods is also presented for the case of the circular cylinder

Synthetic versus biological mesh-related erosion after laparoscopic ventral mesh rectopexy. A systematic review

Purpose: This review reports the incidence of mesh-related erosion after ventral mesh rectopexy to determine whether any difference exists in the erosion rate between synthetic and biological mesh. Methods: A systematic search of the MEDLINE and the Ovid databases was conducted to identify suitable articles published between 2004 and 2015. The search strategy capture terms were laparoscopic ventral mesh rectopexy, laparoscopic anterior rectopexy, robotic ventral rectopexy, and robotic anterior rectopexy. Results: Eight studies (3,956 patients) were included in this review. Of those patients, 3,517 patients underwent laparoscopic ventral rectopexy (LVR) using synthetic mesh and 439 using biological mesh. Sixty-six erosions were observed with synthetic mesh (26 rectal, 32 vaginal, 8 recto-vaginal fistulae) and one (perineal erosion) with biological mesh. The synthetic and the biological mesh-related erosion rates were 1.87% and 0.22%, respectively. The time between rectopexy and diagnosis of mesh erosion ranged from 1.7 to 124 months. No mesh-related mortalities were reported. Conclusion: The incidence of mesh-related erosion after LVR is low and is more common after the placement of synthetic mesh. The use of biological mesh for LVR seems to be a safer option; however, large, multicenter, randomized, control trials with long follow-ups are required if a definitive answer is to be obtained

Co-Ni-Zn Ferrites Fabricated by Spark Plasma Sintering

Ni0,4Co0,2Zn0,4Fe2O4 spinel ferrites have been synthesized by precipitation method from an aqueous solution and bulk samples were fabricated by Spark Plasma Sintering (SPS) to investigate the microstructure and the mechanical properties. Although SPS is considered as a rapid compaction technique, its application is uncommon for ferrites due to reactions occurring between the graphite die and the ferrite powder at elevated temperature. In our tests this problem was circumvented by an alumina film applied on the die. We found that both chemical and phase composition could be retained in the sintered specimens after sintering. In addition, they exhibited improved mechanical properties in terms of hardness (10 GPa) and fracture toughness (2.7 MPa · m−1/2) as compared to conventionally sintered reference samples

Vállalati tőkeszerkezet-politika : Empirikus elemzés a tőzsdei cégek tőkeszerkezet-választásáról 1995-2000 között

A szerző a magyar tőzsdei vállalatok példáján keresztül a leíró statisztika módszerével és ökonometriai modellekkel vizsgálja a tőkeszerkezetet befolyásoló tényezők körét, melyeket az eddigi hasonló tanulmányokhoz képest jelentősen kibővít. Fő következtetése az, hogy a rövid lejáratú források túlsúlya miatt tartósan és tömegesen sérül az eszközforrás lejárati illesztésének elve, ami hátrányosan befolyásolhatja a vállalatok növekedési lehetőségeit, ugyanakkor a különböző tőkestruktúra-teóriák egyszerre és egymást kiegészítve magyarázzák a vállalatok tőkestruktúra-döntéseit, melyek nem elsődlegesek a vállalati döntések sorában

Valutazione pH-manometrica nei pazienti obesi candidati a Sleeve Gastrectomy o bypass gastrico per via laparoscopica

Background: Aim is to evaluate the impact of laparoscopic sleeve gastrectomy (LSG) and gastric bypass (LGB) on gastroesophageal reflux disease (GERD) before and after surgery. Methods: Before surgery, GERD was evaluated by Modified Italian Gastroesophageal reflux disease-Health-Related Quality of Life (MI-GERD-HRQL) questionnaire, manometry, pH-metry, endoscopy and Rx-esophagogram. Based on these exams, patients without GERD underwent LSG and patients with GERD underwent LGB. These exams were repeated 12 months after surgery. Results: Thirteen and 6 patients underwent LSG and LGB, respectively. After LSG, all pH-manometry parameters worsened, with statistically significant difference in median DeMeester score (5.7 vs. 22.7, p=0.0026). De novo GERD occurred in 9 patients (69.2%), with erosive esophagitis in one. No statistically significant differences were observed at endoscopy and Rx esophagogram findings. The median MI-GERD-HRQL score improved from a median of 3 to 0. Overall, nine patients underwent LGB, but three were lost at follow-up. Preoperative pH-manometry changed the surgical indication from LSG to LGB in 7 out of 9 patients (77.8%). Six patients who underwent LGB completed the study, and at pH-manometry, statistically significant differences were observed in percentage of total acid exposure time, number of reflux episodes lasting >5 minutes and DeMeester score (93.8 vs. 3.6, p=0.009). No statistically significant differences were observed at endoscopy and Rx-esophagogram findings. The median MI-GERD-HRQL score improved from a median of 6.5 to 0. Conclusions: LSG has a negative impact on GERD, even in patients without preoperative GERD. LGB was proved to be the intervention of choice in patients with GERD. Preoperative pH-manometry may identify patients with silent GERD, to candidate them to LGB rather than LSG. Preoperative endoscopy, Rx esophagogram and GERD symptoms are not sufficient to decide the most appropriate intervention in obese patients. pH-manometry should be used more liberally to establish the correct surgical indication on objective grounds

Pillanatképek a jászberényi könyvtárosképzés történetéből = Snapshots from the history of library science education in Jászberény

he Teacher Traning Institute in Jászberény opened its gates to its students in 1917. Through years the main profile of the institute has been training teachers. Later, adapting to the social trends, other faculties were launched. The idea of training librarians was first introduced in 1975. My publication is about the very beginning of this phasing out course, its difficulties and changes over time, based on documents, notes and interviews with two of its key figures: Dr Mária Harmat and Dr Tibor Koltay

Hiatoplasty with crura buttressing versus hiatoplasty alone during laparoscopic sleeve gastrectomy

Introduction. In obese patients with hiatal hernia (HH), laparoscopic sleeve gastrectomy (LSG) with cruroplasty is an option but use of prosthetic mesh crura reinforcement is debated. The aim was to compare the results of hiatal closure with or without mesh buttressing during LSG. Methods. Gastroesophageal reflux disease (GERD) was assessed by the Health-Related Quality of Life (GERD-HRQL) questionnaire before and after surgery in two consecutive series of patients with esophageal hiatus ≤ 4 cm2. After LSG, patients in group A (12) underwent simple cruroplasty, whereas in group B patients (17), absorbable mesh crura buttressing was added. Results. At mean follow-up of 33.2 and 18.1 months for groups A and B, respectively (p = 0 006), the mean preoperative GERD-HRQL scores of 16.5 and 17.7 (p = 0 837) postoperatively became 9.5 and 2.4 (p = 0 071). In group A, there was no difference between pre- and postoperative scores (p = 0 279), whereas in group B, a highly significant difference was observed (p = 0 002). The difference (Δ) comparing pre- and postoperative mean scores between the two groups was significantly in favor of mesh placement (p = 0 0058). Conclusions. In obese patients with HH and mild-moderate GERD, reflux symptoms are significantly improved at medium term follow-up after cruroplasty with versus without crura buttressing during LSG.Introduction. In obese patients with hiatal hernia (HH), laparoscopic sleeve gastrectomy (LSG) with cruroplasty is an option but use of prosthetic mesh crura reinforcement is debated. The aim was to compare the results of hiatal closure with or without mesh buttressing during LSG. Methods. Gastroesophageal reflux disease (GERD) was assessed by the Health-Related Quality of Life (GERD-HRQL) questionnaire before and after surgery in two consecutive series of patients with esophageal hiatus ≤ 4 cm2. After LSG, patients in group A (12) underwent simple cruroplasty, whereas in group B patients (17), absorbable mesh crura buttressing was added. Results. At mean follow-up of 33.2 and 18.1 months for groups A and B, respectively (p = 0 006), the mean preoperative GERD-HRQL scores of 16.5 and 17.7 (p = 0 837) postoperatively became 9.5 and 2.4 (p = 0 071). In group A, there was no difference between pre- and postoperative scores (p = 0 279), whereas in group B, a highly significant difference was observed (p = 0 002). The difference (Δ) comparing pre- and postoperative mean scores between the two groups was significantly in favor of mesh placement (p = 0 0058). Conclusions. In obese patients with HH and mild-moderate GERD, reflux symptoms are significantly improved at medium term follow-up after cruroplasty with versus without crura buttressing during LSG