1,721,009 research outputs found
A novel sensor to continuously monitor cardiac apex rotation
No full textThe left ventricular (LV) rotation is a key component of cardiac mechanics as recently shown by advanced imaging techniques. In healthy subjects, the cardiac rotation follows a specific pattern within the cardiac cycle in order to be effective: during isovolumic contraction all short-axis levels, from base to apex, rotate counterclockwise, when viewed from the apex, during ejection, the apex continues counterclockwise while the base reverses direction; thus cardiac apex rotation angle (CAR) reaches the maximum at End of Systole (ES). In diastole, the shearing forces built up during systole by cardiac rotation result in rapid untwisting which is thought to contribute to diastolic suction. Alterations in the normal pattern or magnitude of the cardiac rotation have been associated with cardiovascular diseases, such as chronic heart failure, tachycardia-induced dilated cardiomyopathy, dilated cardiomyopathy, hypertrophic cardiomiopathy, myocardial infarction and aortic stenosis. The analysis of CAR signal with respect to systolic and diastolic phases could be useful for the monitoring of cardiac function in patients with various degrees of heart failure as there are often delay and/or dyssynchrony phenomena which considerably reduce the overall mechanical efficiency of the heart. If an altered rotational dynamics determines a delay of maximum CAR into the Isovolumic Relaxation Period (IRP), the effective contribution of left ventricular twisting to systole must be considered the CAR value at the time of ES (CARES).
Continuous monitoring of LV rotation has not been attempted so far but may provide important information for long term management of heart failure patients.
We propose the use of an implantable gyroscopic sensor for the continuous monitoring of CAR. We evaluated in animals the CAR signal with respect to the systolic timing (CARES) and we tested its ability to reflect changes of LV function during acute ischemia
Protesi speciale di spalla nel trattamento chirurgico conservativo dei tumori dell'apparato muscolo-scheletrico
No full textProtesi speciale di spalla nel trattamento chirurgico conservativo dei tumori dell'apparato muscolo-scheletrico
La nuova centrale di sterilizzazione dell’Azienda Ospedaliero Universitaria Policlinico S. Orsola Malpighi
No full textUna nuova centrale di Steritizzazione dell'Azienda Ospedaliero
Universitaria Policlinico S. Orsola Malpighi è stata realizzata all'interno del Nuovo Polo Chirurgico e dell'Emergenza.
Occupa una superticie di circa 1.100 mq ed è stata dimensionata
per poter gestire oltre 40.000 interventi/anno.
L'Azienda ha posto come oggetto della gara di appalto la
progettazione, realizzazione, gestione, conduzione e manutenzione della centrale di sterilizzazione, con lo scopo di ottenere un servizio in grado dirispondere in modo efficace ed efficiente alle esigenze di sterilizzazione dei dispositivi medici, nel rispetto delle normative vigenti. Nella nuova centrale è stata posta particolare attenzione ai flussi del materiale ed ai percorsi del personale, oltre che a tutti gli elementi necessari per garantire un elevato grado di comfort per gli
operatori, come ad esempio la presenza di illuminazione naturale in tutti gli ambienti con presenza continuativa di personale
The new central sterile supply department of university hospital authority St. Orsola-Malpighi Polyclinic
No full textThe new centrol sterile supply Deportment (CSSD) of the University Hospital Authority St. Orsola-Malpighi
Polyclinic was inaugurated in September 2010. The CSSD collects functions of diagnosis and treatment of high technological impact, such as emergency room, diagnostic imaging, operating blocks and intensive care. The intervention was executed by a service contract for the design, construction, management, operation and maintenance of the unique CSSD
A novel implantable sensor to monitor both apical rotation and cardiac phases
No full textObjectives: The magnitude and timing of Left Ventricular (LV) twist with respect to cardiac phases are essential to detect systolic and diastolic dysfunction, as recently shown by advanced imaging techniques. No implantable sensors are
currently available to provide that phasic analysis of LV rotation over the cardiac cycle. We developed and evaluated in a sheep model an innovative implantable gyroscopic sensor for the continuous endocardial monitoring of both the amount and timing of cardiac rotation.
Methods: In a sheep, a tip catheter gyroscopic sensor was inserted in the endocardium of the right ventricle apex. The detected signal (EndoTwist) was continuously recorded along with ECG, LV pressure (LVP) and its first derivate (LVdP/dt). EndoTwist was processed in order to obtain both cardiac rotation parameters (twist rate ω, apical rotation angle θ) and mechanical heart vibrations (MHVs) used to identify systole and diastole.
Results: The detected EndoTwist signal clearly showed both a low-frequency component relating to cardiac rotation (ω, θ) and a high frequency component relating to MHVs. Identification of systole and diastole from MHVs was confirmed by comparison with LVdP/dt which was previously used to define the timing of the cardiac cycle.
Conclusions: The new implantable sensor permits detection of cardiac twist dynamics (ω, θ) with respect to the entire cardiac cycle by means of MHVs recognition. This information, if confirmed in larger studies, has promising clinical implication for the monitoring of cardiac function in heart failure patients
Organizzazione e gestione di una banca dell'osso
No full textOrganizzazione e gestione di una banca dell'osso
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Validation of a new cardiac resynchronization therapy optimization algorithm based on peak endocardial acceleration: first clinical results
No full textVariations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
- …
