4 research outputs found
Atypical varicella-zoster virus reactivation: a case report
No full textVaricella-zoster virus (VZV) commonly causes benign skin manifestations in children; it then establishes a latent infection and may reactivate, causing herpes zoster. The most common zoster complication is postherpetic neuralgia, but complications can also occur without a rash. VZV infection may cause neurological manifestations and even vasculopathy may occur, in both primary and reactivated VZV infection. Thrombotic complications are mainly described in children, while a few case reports have described cerebral venous sinus thrombosis (CVST), deep-vein thrombosis of the lower limbs and pulmonary embolism in adults. In this article we report the case of a young woman who developed systemic thromboembolic sequelae due to a hypercoagulable state following VZV reactivation. She had deep venous lower-limb thrombosis extended to the inferior vena cava (IVC), massive pulmonary embolism and CVST. Moreover, VZV reactivation caused an acute hepatitis and clinical manifestations suggesting viral encephalitis
Previsione della vita a fatica di un telaio motociclistico mediante tecniche numeriche e sperimentali
No full textLAUREA SPECIALISTICAIl seguente documento ha lo scopo di descrivere l’analisi del comportamento a fatica effettuata sul telaio di un motociclo Husqvarna TC250/10. Sono state effettuate analisi ad elementi finiti (FEM) e test sperimentali.
Le analisi FEM sono state eseguite al fine di analizzare gli stati di sforzo del telaio in diverse configurazioni di carico per individuarne le zone critiche, in particolare nelle giunzioni saldate. In una fase successiva sono state eseguite le analisi a fatica (sempre tramite un codice agli elementi finiti) sul telaio, con lo scopo di stimare la vita a fatica.
Tramite i test sperimentali è stato validato il modello ad elementi finiti. Questo ha permesso di apportare delle modifiche costruttive atte a migliorarne la resistenza a fatica.
L'utilizzo delle analisi ad elementi finiti e l'accuratezza del modello creato hanno permesso di velocizzare l’intero processo di progettazione e di ridurre sensibilmente la fase di sperimentazione necessaria.The fatigue analysis of the Husqvarna TC250/10’s motorcycle chassis is described in the thesis. A finite element method (FEM) and experimental tests have been used.
A finite element model of the chassis has been created. A static FEM analysis was used to analyze the stress states of the chassis, in two different load case. So it has been used to analyzed the stress states of the chassis, for different load cases. It has been possible to locate the areas with maximum stress value is reached. In a second step, the model of the chassis has been used for estimating the fatigue life.
The test bench results have been used to validate the finite element model. New technical solutions have been proposed and verified by means of the finite element analysis.
The method allowed to speed up the design process and to reduce the testing phase
Comparison between invasive and noninvasive techniques of evaluation of microvascular structural alterations
No full textThe evaluation of the morphological characteristics of small resistance arteries in humans is challenging. The gold standard method is generally considered to be the measurement by wire or pressure micromyography of the media-to-lumen ratio of subcutaneous small vessels obtained by local biopsies. However, noninvasive techniques for the evaluation of retinal arterioles were recently proposed; in particular, two approaches, scanning laser Doppler flowmetry (SLDF) and adaptive optics, seem to provide useful information; both of them provide an estimation of the wall-to-lumen ratio (WLR) of retinal arterioles. Moreover, a noninvasive measurement of basal and total capillary density may be obtained by videomicroscopy/capillaroscopy. No direct comparison of these three noninvasive techniques in the same population was previously performed; in particular, adaptive optics was never validated against micromyography
Recommended from our members
Respiratory muscle work and inspiratory muscle training on cytokines, oxidative stress and diaphragm fatigue in younger and older populations
No full textIncreased respiratory muscle work is encountered during strenuous whole-body exercise, and at rest in older adults and those with pulmonary limitations such as chronic obstructive pulmonary disease (COPD). When sufficiently strenuous it can result in diaphragmatic fatigue, increased blood lactate concentrations, and an alteration in respiratory muscle recruitment patterns. Increased respiratory muscle work also elevates cytokines interleukin-6 (IL-6) and interleukin-1β (IL-1β) within the respiratory muscles and systemically. There is mounting evidence that inflammation contributes significantly to the ageing process and age related diseases. Enhanced oxidative stress, glycogen depletion and diaphragmatic fatigue are all potential stimuli for this production. Whole-body exercise training can attenuate systemic inflammation and oxidative stress in younger adults during exercise, and in older adults who experience this at rest. An attenuation of muscle glycogen or increases in antioxidant enzymes may explain such reductions. Inspiratory muscle training (IMT) may also elicit similar adaptations in the inspiratory muscles, and thus also attenuate these markers
