Search results for "Mesh"

Adaptive meshes in computer graphics and model-based simulation

2006

Monet luonnonlait voidaan ilmaista matemaattisesti joko yhtenä yhtälönä tai yhtälöjärjestelmänä. Erityisesti differentiaaliyhtälöiden ratkaisu on tärkeä esimerkiksi mekaniikassa, biologiassa tai kemiassa esiin tuleva ongelma. Useimmissa tapauksissa ratkaisu tällaisiin yhtälöihin on tuntematon, joten se täytyy löytää käyttäen tietokonekoodia. Koska tietokoneet toimivat rajoitetulla tarkkuudella ja tietomäärällä, tietokoneella saatu ratkaisu on vain approksimaatio yhtälön ratkaisulle. Tämän epätarkan tiedon käyttö tietokoneavusteisessa tekniikassa voi johtaa laitteen toimintahäiriöihin. Onkin tärkeää saada kuva, kuinka hyvin tietokoneella saatu tulos edustaa tarkkaa ratkaisua. Turchyn kehitti…

A coupled discontinuous Galerkin-Finite Volume framework for solving gas dynamics over embedded geometries

2021

Author(s): Gulizzi, Vincenzo; Almgren, Ann S; Bell, John B | Abstract: We present a computational framework for solving the equations of inviscid gas dynamics using structured grids with embedded geometries. The novelty of the proposed approach is the use of high-order discontinuous Galerkin (dG) schemes and a shock-capturing Finite Volume (FV) scheme coupled via an $hp$ adaptive mesh refinement ($hp$-AMR) strategy that offers high-order accurate resolution of the embedded geometries. The $hp$-AMR strategy is based on a multi-level block-structured domain partition in which each level is represented by block-structured Cartesian grids and the embedded geometry is represented implicitly by a…

Alveolar ridge reconstruction with titanium meshes: A systematic review of the literature

2014

Alveolar bone regeneration by means of titanium meshes is a widespread procedure, however to date, only few relevant studies were reported in literature concerning this technique. Consequently, the aim of the present systematic review was to analyze the reliability of the titanium mesh as a barrier, in conjunction with horizontal and vertical ridge reconstruction for implant placement purposes. A total of 17 articles complying with the inclusion and exclusion criteria were reviewed. Three outcome variables were defined: a) horizontal and vertical bone regeneration obtained, b) complication rate, defined as the percentage of membrane exposures and c) evaluation of implant survival, success a…

Impact of the Tiloop Bra mesh in CT images and dose delivery in breast radiotherapy

2012

A new titanized breast mesh, TiLOOP Bra, is currently available for implantation in patients who require radiotherapy. The purpose of this work is to study the dosimetric effect of the presence of a TiLOOP Bra mesh on breast radiation treatment and radiographic imaging. The dosimetric effects have been measured for three X‐ray energies: 1.25 MeV, 6 MV and 18 MV, using radiochromic films placed at three different depths. These depths are representative of mesh location in breast during the radiotherapy treatment and hence, are of interest in this study. In order to assess the disturbance in a radiographic image, different computed tomographic (CT) studies of the mesh have been performed. The…

The use of a proximal protection system, a reperfusion catheter, and new-generation mesh stents in combined endovascular therapy for a long, symptoma…

2020

Endovascular management of carotid and vertebral artery dissections with new generation double-mesh stent and protection systems – single-center earl…

2019

Introduction Symptomatic dissections (SD) of cervical arteries are still a therapeutic problem. Although endovascular management (EM) is currently a preferred method of treatment of SD, complications associated with this method of treatment in published reports are quite frequent (3-16%). Aim In this retrospective study we analyzed the results of EM with novel, double-mesh stent and protection systems (PS) for SD of the internal carotid (IC) or vertebral arteries (VA) that coexisted with hemodynamically significant stenosis or aneurysmatic dilatation of the dissected artery. Material and methods We evaluated the results of EM in 19 patients (men 15, median age: 55, range: 25-83), presenting…

Childhood maltreatment and clinical severity of treatment‐resistant depression in a French cohort of outpatients (FACE‐DR): One‐year follow‐up

2020

International audience; Childhood maltreatment is associated with major depressive disorder (MDD). It not only increases the risk of lifetime MDD, but it also aggravates its course. Among depressed patients, 20-30% of them experience treatment-resistance depression (TRD). We aimed to assess the association between childhood maltreatment, severity of depression in a unipolar TRD sample, and patient outcomes after one-year of follow-up. Methods: Patients were recruited for a prospective cohort from the French network of TRD expert centers. Depressive symptom severity was assessed with the Montgomery-Åsberg Depression Rating Scale (MADRS) and the Quick Inventory of Depressive Symptomatology se…

Smartphone-based ecological momentary assessment (EMA) in psychiatric patients and student controls: A real-world feasibility study

2020

Abstract Background Smartphone-based ecological momentary assessment (EMA) is a promising methodology for mental health research. The objective of this study is to determine the feasibility of smartphone-based active and passive EMA in psychiatric outpatients and student controls. Methods Two smartphone applications —MEmind and eB2— were developed for behavioral active and passive monitoring. The applications were tested in psychiatric patients with a history of suicidal thoughts and/or behaviors (STB), psychiatric patients without a history of STB, and student controls. Main outcome was feasibility, measured as response to recruitment, retention, and EMA compliance. Secondary outcomes were…

Impact of domestic mould exposure on Aspergillus biomarkers and lung function in patients with chronic obstructive pulmonary disease

2021

International audience; Patients with chronic obstructive pulmonary disease (COPD) are frequently colonised or sensitised by Aspergillus, but clinical significance remains unclear. Furthermore, little is known on the impact of indoor mould exposure during COPD. In this study, we assessed the relationship between domestic mould exposure, Aspergillus biomarkers and COPD severity during acute exacerbation and at stable state. Aspergillus section Fumigati culture in sputum and anti-Aspergillus antibodies detection (IgG and precipitins) were followed up in COPD patients that were prospectively recruited during exacerbation (n = 62), and underwent a visit at stable state after 18 months (n = 33).…

Cardiac complications after laparoscopic large hiatal hernia repair. Is it related with staple fixation of the mesh? -Report of three cases

2015

Introduction Laparoscopic Nissen operation with mesh reinforcement remains being the most popular operation for large hiatal hernia repair. Complications related to mesh placement have been widely described. Cardiac complications are rare, but have a fatal outcome if they are misdiagnosed. Presentation of cases We sought to outline our institutional experience of three patients who developed cardiac complications following a laparoscopic Nissen operation for large hiatal hernia repair. Discussion Laparoscopic hiatoplasty and Nissen fundoplication are safe and effective procedures for the hiatal hernia repair, but they are not exempt from complications. Fixation technique and material used m…