878 research outputs found
Association between obstructive apnea syndrome during sleep and damages to anterior labyrinth: Our experience
The obstructive sleep apnea syndrome is a chronic condition characterized by frequent episodes of collapse of the upper airways during sleep. It can be considered a multisystem disease. Among the districts involved, even the auditory system was seen to be concerned. It was enrolled a population of 20 patients after polysomnographic diagnosis of OSAS (Apnea Hypopnea Index > 10) and a control group of 28 healthy persons (Apnea Hypopnea Index < 5). Each patient has been subjected to Pure Tone Audiometry, Tympanometry, study of Acoustic Reflex, Otoacoustic Emissions and Auditory Brainstem Response. Moreover they were submitted to endoscopy of upper airway with Muller Maneuver and Epworth Sleepiness Scale (ESS). The values of ESS was 13.5 in OSAS group and 5.4 in control group. The tone audiometry is worse in all frequencies analyzed in OSAS patients, but within the normal range for both groups analyzed by 250 to 1000 Hertz. Otoacoustic emissions show a reduced reproducibility and a lower signal/ noise ratio in OSAS group (P <0.01)
Laser Scanner 3D per lo studio e la catalogazione dell’archeologia medievale: la chiesa di Santa Croce in Bergamo
The improvement of new active optical sensors has revolutionized the methods for documenting cultural heritage. The conservation and appreciation of our cultural legacy re¬quire an extensive documentation both in terms of shape, color and geometry as well as the more traditional art-historical features. The incessant development of scientific research today provides new possibilities and tools which are essential to know and use in a responsible and scientific way. In the field of archaeology, the automatic 3D survey is now recognized as an added value compared to traditional practices and the active contribution that this technology can provide to the interpretative phase, cataloguing and promotion of archaeological assets, even through the web, is becoming increasingly clear. On the other hand, even considering the speed of the procedure and the accuracy of measurement, there have been calls for reflection on the role that laser scanning can play in the field of archaeology; this role needs to be clarified and consolidated by conducting new studies and experiments, such as the one presented here that concerns the Church of Santa Croce in Bergamo, a small octagonal Romanesque chapel built in the first half of the 11th century
Fatigue damage modelling of PEEK short fibre composites
Abstract In the present research the fatigue damage evolution of a PEEK based composite was studied. Examined material consisted of a PEEK matrix reinforced by carbon micro-fibres with addition of fillers such as graphite and PTFE. Fatigue tests in load control were carried out up to 106 cycles at different stress level, with cycle ratio R = 0 and frequency 10 Hz. The damage evolution was evaluated by defining damage parameter based on elastic modulus reduction observed under cyclic loading. The cyclic damage evolution of PEEK based composite, which is a function of applied stress level, presented significantly different damage stages. In order to reproduce fatigue damage kinetic observed experimentally a phenomenological modelling approach was then implemented into a finite element code, based on fatigue damage model recently proposed for short fibre reinforced thermoplastic composites
A numerical approach for the analysis of deformable journal bearings
This paper presents a numerical approach for the analysis of hydrodynamic radial journal bearings. The effect of shaft and housing elastic deformation on pressure distribution within oil film is investigated. An iterative algorithm that couples Reynolds equation with a plane finite elements structural model is solved. Temperature and pressure effects on viscosity are also included with the Vogel-Barus model. The deformed lubrication gap and the overall stress state were calculated. Numerical results are presented with reference to atypical journal bearing configuration at two different inlet oil temperatures. Obtained results show the great influence of elastic deformation of bearing components on oil pressure distribution, compared with results for ideally rigid components obtained by Raimondi and Boyd solution
Fatigue behavior and cyclic damage of peek short fiber reinforced composites
Fatigue strength and failure mechanisms of short fiber reinforced (SFR) PEEK have been investigated in
the past by several research groups. However some relevant aspects of the fatigue behavior of these
materials, like cyclic creep and fatigue damage accumulation and modeling, have not been studied yet,
in particular in presence of both fillers and short fibers as reinforcement. In the present research these
aspects were considered by carrying out uni-axial fatigue tests in load control (cycle ratio R = 0) on neat
PEEK and PEEK based composites reinforced either with short carbon fibers only or with addition of fillers
(graphite and PTFE). For each material stress-life curves were obtained and compared. Fatigue fracture
surfaces were analyzed to identify failure mechanisms in presence of different reinforcement types.
The evolution of cyclic creep strain was also monitored as a function of the number of cycles, thus allowing
investigation on the correlation between cyclic creep parameters and fatigue life. The evolution of
cyclic damage with loading cycles was then compared by defining a damage parameter related to the
specimen stiffness reduction observed during the tests. Progressive cyclic damage evolution of short fiber
reinforced PEEK composites presented significantly different patterns depending on applied stress level
and on the presence of different reinforcement typologies. In order to reproduce the different fatigue
damage kinetics and stages of progressive damage accumulation observed experimentally, a cyclic
damage model was finally developed and implemented into a finite element code by which a satisfactory
agreement between numerical prediction and experimental data at different stress levels for each examined
material
Tavole
Fotoraddrizzamenti, modello 3D, campagna fotografica del ciclo dipinto e del mosaico, con relative didascalieDigital image rectifications, 3D, Wall paintings and mosaics full color plates, with caption
Bipolar Quantum Molecular Resonance versus Blunt Dissection tonsillectomy
Bipolar Quantum Molecular Resonance versus Blunt Dissection tonsillectomy. Objectives: This study compared a quantum molecular resonance tonsillectomy (QMRT) to a standard blunt dissection tonsillectomy (BDT) for effectiveness and safety. Methodology: From January 2011 to September 2012, we recruited 80 children (ages 3 to 16 y) with paediatric obstructive sleep apnoea syndrome and/or recurrent tonsillitis. Patients were randomly assigned to receive QMRT (N = 40) or BDT (N = 40). The operating time and blood loss during surgery were evaluated. During the first postoperative week, the patients' parents completed a questionnaire to evaluate bleeding, ear and neck pain, nausea, vomiting, interrupted sleep, oral liquid intake or discomfort in fluid assumption, and analgesic consumption. Results: The average tonsillectomy duration was significantly shorter in the QMRT group (22.07 min \ub1 9.05) than in the BDT group (35.12 min \ub1 13.32; p < 0.000005). The average blood loss during tonsillectomy was significantly lower for the QMRT group (5.62 ml \ub1 7.44) than for the BDT group (43 ml \ub1 33.20; p < 000000001). However, the BDT group reported significantly lower pain scores than the QMRT group on days 2 (p < 0.05), 5 (p < 0.05), and 6 (p < 0.05); on other days, the groups were not significantly different. The BDT group reported two early and one late bleeding episodes; the QMRT group recorded only two late bleeding episodes. Conclusions: QMRT significantly reduced the operating time and intra-operative blood loss. No significant differences were found between the two techniques in postoperative pain or bleeding
Human Listeriosis in Piedmont, Northern Italy (2010-2013): an insight on surveillance efficacy and strain diffusion
Outpatient satisfaction during pharmacotherapy followup
This study aimed to investigate the satisfaction of patients with uncontrolled hypertension referred for pharmacotherapy followup. A cross-sectional study by semi-structured interview was used. The sample comprised patients undergoing pharmacotherapy followup, patients who had discontinued pharmacotherapy followup and patients who had not kept the appointments. A total of 80 (76.9 %) out of 104 patients registered were contacted. The majority of patients undergoing pharmacotherapy followup (91.1 %) were fully satisfied with the pharmacists' care given, their relationship with them (94.9 %), the manner in which their therapy was conducted (99.2 %) and the environment where it was carried out (85.3 %). The reasons for non-attendance were mostly forgetting the date, illness on the appointment day and other arrangements on the same day. Interestingly, all of these patients were completely satisfied with the pharmacists' care given. The satisfaction of patients with the pharmaceutical care is high among patients that have continuous followup, but a relevant proportion discontinued followup. Newer approaches to keep these patients under followup are necessary.Colegio de Farmacéuticos de la Provincia de Buenos Aire
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