Search results for "Structural system"

Pulmonale Struktur und Funktion - Hochauflösende und dynamische Computertomographie bei Lungenemphysem und Erkrankungen der Atemwege -

2002

Computed tomography (CT) is the method of choice for the morphological assessment of pulmonary structure. Airways. pulmonary parenchyma and their pathologies are shown with high spatial resolution. Airway diseases exhibit bronchial dilatation, wall thickening and an increased visibility in the lung periphery. CT is also the imaging gold standard for the detection and the characterisation of emphysema because a high degree of concordance with histopathological studies. Centrilobular, panlobular and paraseptal emphysema can be differentiated. CT can also provide functional information. Paired inspiratory and expiratory scans with or without spirometric triggering allow to evaluate obstruction…

A Case of Severe Dyspnea and an Unusual Bronchoscopy: The Chilaiditi Syndrome

2006

Oxidative and nitrosative stress in the diaphragm of patients with COPD.

2007

COPD is associated with an increased load on the diaphragm. Since chronic muscle loading results in changes in antioxidant capacity and formation of reactive oxygen and reactive nitrogen species, we hypothesized that COPD has a similar effect on the diaphragm, which is related to the severity of COPD. Catalase activity was determined spectrophotometrically. Levels of 4-hydroxy-2-nonenal (HNE)-protein adducts and 3-nitrotyrosine (NT) formation were measured using western blotting. Levels of malondialdehyde (MDA) were assessed by high-performance liquid chromatography. We found that catalase activity was approximately 89% higher in the diaphragm of severe COPD patients (FEV1 37+/-5% predicted…

A modal approach for the evaluation of the response sensitivity of structural systems subjected to non-stationary random processes

2005

A method for the evaluation of the response sensitivity of both classically and non-classically damped discrete linear structural systems under stochastic actions is presented. The proposed approach requires the following items: (a) a suitable modal expansion of the response; (b) the derivation in analytical form of the equations governing the evolution of the derivatives of the response (the so-called sensitivity equations) with respect to the parameters that define the structural model; (c) an extensive use of the Kronecker algebra for determining the analytical expressions of the sensitivity of the structural response statistics to non-stationary random input processes. Moreover, a step-…

Right diaphragmatic injury and lacerated liver during a penetrating abdominal trauma: case report and brief literature review

2014

Introduction: Diaphragmatic injuries are rare consequences of thoracoabdominal trauma and they often occur in association with multiorgan injuries. The diaphragm is a difficult anatomical structure to study with common imaging instruments due to its physiological movement. Thus, diaphragmatic injuries can often be misunderstood and diagnosed only during surgical procedures. Diagnostic delay results in a high rate of mortality. Methods: We report the management of a clinical case of a 45-old man who came to our observation with a stab wound in the right upper abdomen. The type or length of the knife used as it was extracted from the victim after the fight. CT imaging demonstrated a right hem…

Mathematical Modeling and Parameters Estimation of Car Crash Using Eigensystem Realization Algorithm and Curve-Fitting Approaches

2013

Published version of an article in the journal: Mathematical Problems in Engineering. Also available from the publisher at: http://dx.doi.org/10.1155/2013/262196 Open Access An eigensystem realization algorithm (ERA) approach for estimating the structural system matrices is proposed in this paper using the measurements of acceleration data available from the real crash test. A mathematical model that represents the real vehicle frontal crash scenario is presented. The model's structure is a double-spring-mass-damper system, whereby the front mass represents the vehicle-chassis and the rear mass represents the passenger compartment. The physical parameters of the model are estimated using cu…

Performance of EasyBreath® Decathlon Snorkeling mask for Delivering Continuous Positive Airway Pressure

2020

ABSTRACTBackgroundDuring the COVID-19 pandemic, the need for noninvasive respiratory support devices has dramatically increased, sometimes exceeding hospital capacity. The full-face Decathlon snorkeling mask, EasyBreath® (EB® mask), has been adapted to deliver continuous positive airway pressure (CPAP) as an emergency respiratory interface. We aimed to assess the performance of this modified EB® mask.MethodsCPAP set at 5, 10, and 15 cmH2O was delivered to 10 healthy volunteers with a high-flow system generator set at 40, 80, and 120 L min-1 and with a turbine-driven ventilator during both spontaneous and loaded (resistor) breathing. Inspiratory CO2 partial pressure (PiCO2), pressure inside …

Successful laparoscopic management of congenital diaphragmatic relaxation: A case report

2020

Highlights • We describe a case report of congenital Diaphragmatic relaxation treated with totally laparoscopic plication of the left hemidiaphragm with nonresorbable sutures. • In our case report the diaphragmatic relaxation seemed to be congenital and the laparoscopic approach resulted the most appropriate technique to obtain the repositioning of abdominal organs and diaphragmatic placation. • A brief review of literature was performed to identify outcomes and potentially surgical advantages of laparoscopic approach for diaphragmatic relaxation. Laparoscopic approach can only be practiced in selected cases.

Direct evaluation of the equivalent linear damping for TLCD systems in random vibration for pre-design purposes

2014

Abstract Passive control of structural vibrations has received in recent years a great attention from researchers concerned with vibration control. Several types of devices have been proposed in order to reduce the dynamic responses of different kinds of structural systems. Among them, the Tuned Liquid Column Damper (TLCD) proved to be very effective in reducing vibration of structures. Since the increasing use of TLCDs in practical realizations, this paper aims at developing an approximate formulation, by means of a statistical linearization technique, able to estimate the parameters of a structure equipped with a TLCD subjected to random loads for pre-design purposes. Moreover, it is show…

Methods for optimal shape design of electrical devices

1996

Often the primary problem facing designers of structural systems is determining the shape of the structure. In spite of graphical work stations and modern software for analyzing the structure, finding the best geometry for the structure by “trial and error” is still a very tedious and timeconsuming task. The goal in optimal shape design (structural optimization, or redesign) is to computerize the design process and therefore shorten the time it takes to design new products or improve the existing design. Structural optimization is already used in many applications in industry. In general, however, structural optimization is just beginning to penetrate the industrial community. Integrating F…