910 resultados para initial chamber
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Dissertação para obtenção do Grau de Doutor em Engenharia Física
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INTRODUCTION: Mitral regurgitation (MR) is the most common valvular disease and has recently become the target of a number of percutaneous approaches. The MitraClip is virtually the only device for which there is considerable experience, with more than 20,000 procedures performed worldwide. OBJECTIVE: To describe our initial experience of the percutaneous treatment of MR with the MitraClip device. METHODS: We describe the first six MitraClip cases performed in this institution (mean age 58.5 ± 13.1 years), with functional MR grade 4+ and New York Heart Association (NYHA) heart failure class III or IV (n=3), with a mean follow-up of 290 ± 145 days. RESULTS: Procedural success (MR ≤ 2+) was 100%. Total procedure time was 115.8 ± 23.7 min, with no in-hospital adverse events and discharge between the fourth and eighth day, and consistent improvement in the six-minute walk test (329.8 ± 98.42 vs. 385.33 ± 106.95 m) and in NYHA class (three patients improved by two NYHA classes). During follow-up there were two deaths, in two of the four patients who had been initially considered for heart transplantation. CONCLUSION: In patients with functional MR the MitraClip procedure is safe, with both a high implantation and immediate in-hospital success rate. A longer follow-up suggests that the clinical benefit decreases or disappears completely in patients with more advanced heart disease, namely those denied transplantation or on the heart transplant waiting list.
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics
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A young male developed hearing loss, vertigo, headache and facial palsy. Neurological examination did not show any abnormalities. Two years later, cervical lymphadenopathy, hepatosplenomegaly and atypical lymphocytes in peripheral blood revealed leukemia. At the same time, acquired ichthyosis was observed. Subsequently, neurological abnormalities revealed myelopathy associated with HTLV-1, due to vertical transmission.
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INTRODUCTION: Injuries caused by sea urchins are the most common caused by marine animals in humans in Brazil, with the black sea urchin (Echinometra lucunter) causing the most injuries to bathers. METHODS: This study observed 314 human wounds with emphasis on the early observation of clinical signs and symptoms and their implications on the recommended treatment. RESULTS: All the injuries were caused by black sea urchins and were observed in bathers. The lesions and the pain were associated with penetration of the spines; there was no early inflammation or pain without pressure on the wounded places. Complications arising from this kind on injury, including infections and foreign body granulomas, are associated with the permanence of the spines in the wounds. CONCLUSIONS: The study confirmed that this kind of injury is the most common accident caused by aquatic animals in Brazil. The main therapeutical recommendation is early removal of the spines to prevent late complications, such as infections and the formation of foreign body granulomas.
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In cataract surgery, the eye’s natural lens is removed because it has gone opaque and doesn’t allow clear vision any longer. To maintain the eye’s optical power, a new artificial lens must be inserted. Called Intraocular Lens (IOL), it needs to be modelled in order to have the correct refractive power to substitute the natural lens. Calculating the refractive power of this substitution lens requires precise anterior eye chamber measurements. An interferometry equipment, the AC Master from Zeiss Meditec, AG, was in use for half a year to perform these measurements. A Low Coherence Interferometry (LCI) measurement beam is aligned with the eye’s optical axis, for precise measurements of anterior eye chamber distances. The eye follows a fixation target in order to make the visual axis align with the optical axis. Performance problems occurred, however, at this step. Therefore, there was a necessity to develop a new procedure that ensures better alignment between the eye’s visual and optical axes, allowing a more user friendly and versatile procedure, and eventually automatizing the whole process. With this instrument, the alignment between the eye’s optical and visual axes is detected when Purkinje reflections I and III are overlapped, as the eye follows a fixation target. In this project, image analysis is used to detect these Purkinje reflections’ positions, eventually automatically detecting when they overlap. Automatic detection of the third Purkinje reflection of an eye following a fixation target is possible with some restrictions. Each pair of detected third Purkinje reflections is used in automatically calculating an acceptable starting position for the fixation target, required for precise measurements of anterior eye chamber distances.
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A case of malignant neoplasm is described in which the initial manifestations were mental dysfunction and meningeal irritation, mimicking chronic or subacute meningitis. Physical examination showed cranial nerve involvement and a pelvic tumor. There was progressive deterioration, and death occurred in 2 weeks. The autopsy revealed a gallbladder adenocarcinoma, meningeal carcinomatosis, and ovarian metastasis presenting as a Krukenberg tumor. The authors emphasize the importance of including meningeal carcinomatosis as a possibility in the differential diagnosis of non-characteristic clinical pictures, as well as the importance of the cerebrospinal fluid cytologic examination, repeated as needed, in order to confirm this diagnosis.
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The considerable amount of energy consumed on Earth is a major cause for not achieving sustainable development. Buildings are responsible for the highest worldwide energy consumption, nearly 40%. Strong efforts have been made in what concerns the reduction of buildings operational energy (heating, hot water, ventilation, electricity), since operational energy is so far the highest energy component in a building life cycle. However, as operational energy is being reduced the embodied energy increases. One of the building elements responsible for higher embodied energy consumption is the building structural system. Therefore, the present work is going to study part of embodied energy (initial embodied energy) in building structures using a life cycle assessment methodology, in order to contribute for a greater understanding of embodied energy in buildings structural systems. Initial embodied energy is estimated for a building structure by varying the span and the structural material type. The results are analysed and compared for different stages, and some conclusions are drawn. At the end of this work it was possible to conclude that the building span does not have considerable influence in embodied energy consumption of building structures. However, the structural material type has influence in the overall energetic performance. In fact, with this research it was possible that building structure that requires more initial embodied energy is the steel structure; then the glued laminated timber structure; and finally the concrete structure.
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The bond behavior between Fiber Reinforced Polymers (FRPs) and masonry substrates has been the subject of many studies during the last years. Recent accelerated aging tests have shown that bond degradation and FRP delamination are likely to occur in FRP-strengthened masonry components under hygrothermal conditions. While an investigation on the possible methods to improve the durability of these systems is necessary, the applicability of different bond repair methods should also be studied. This paper aims at investigating the debonding mechanisms after repairing delaminated FRP-strengthened masonry components. FRP-strengthened brick specimens, after being delaminated, are repaired with two different adhesives: a conventional epoxy resin and a highly flexible polymer. The latter is used as an innovative adhesive in structural applications. The bond behavior in the repaired specimens is investigated by performing single-lap shear bond tests. Digital image correlation (DIC) is used for deeper investigation of the surface deformation and strains development. The effectiveness of the repair methods is discussed and compared with the strengthened specimens.
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For any vacuum initial data set, we define a local, non-negative scalar quantity which vanishes at every point of the data hypersurface if and only if the data are Kerr initial data. Our scalar quantity only depends on the quantities used to construct the vacuum initial data set which are the Riemannian metric defined on the initial data hypersurface and a symmetric tensor which plays the role of the second fundamental form of the embedded initial data hypersurface. The dependency is algorithmic in the sense that given the initial data one can compute the scalar quantity by algebraic and differential manipulations, being thus suitable for an implementation in a numerical code. The scalar could also be useful in studies of the non-linear stability of the Kerr solution because it serves to measure the deviation of a vacuum initial data set from the Kerr initial data in a local and algorithmic way.
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Dissertação de mestrado Internacional em Sustentabilidade do Ambiente Construído
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"Series title: Springerbriefs in applied sciences and technology, ISSN 2191-530X"
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OBJECTIVE: To assess the changes in ventricular evoked responses (VER) produced by the decrease in left ventricular outflow tract gradient (LVOTG) in patients with hypertrophic obstructive cardiomyopathy (HOCM) treated with dual-chamber (DDD) pacing. METHODS: A pulse generator Physios CTM (Biotronik, Germany) was implanted in 9 patients with severe drug-refractory HOCM. After implantation, the following conditions were assessed: 1) Baseline evaluation: different AV delay (ranging from 150ms to 50 ms) were sequentially programmed during 5 to 10 minutes, and the LVOTG (as determined by Doppler echocardiography) and VER recorded; 2) standard evaluation, when the best AV delay (resulting in the lowest LVOTG) programmed at the initial evaluation was maintained so that its effect on VER and LVOTG could be assessed during each chronic pacing evaluation. RESULTS: LVOTG decreased after DDD pacing, with a mean value of 59 ± 24 mmHg after dual chamber pacemaker, which was significantly less than the gradient before pacing (98 + 22mmHg). An AV delay >100ms produced a significantly lower decrease in VER depolarization duration (VER DD) when compared to an AV delay <=100ms. Linear regression analyses showed a significant correlation between the LVOTG values and the magnitude of VER (r=0.69; p<0.05) in the 9 studied patients. CONCLUSION: The telemetry obtained intramyocardial electrogram is a sensitive means to assess left ventricular dynamics in patients with HOCM treated with DDD pacing.
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OBJECTIVE: To evaluate the use of the intraaortic balloon (IAoB) in association with coronary angioplasty in high-risk patients. METHODS: Fourteen high-risk patients unresponsive to clinical therapy and with formal contraindication to surgical revascularization were treated by coronary angioplasty, most of which was followed by stenting. All procedures were performed with circulatory support with the IAoB. This study reports the early results and the late findings after 12 months of follow-up. Six patients had multivessel coronary disease; of these, four had left main equivalent lesions and two had unprotected left main coronary artery disease, one of whom had severe "end-vessel" stenosis and the other was a patient with Chagas' disease with single-vessel lesion. Eleven patients had a left ventricular ejection fraction <30%. RESULTS: In 100% of the patients, the procedures were initially successful. Two patients had severe bleeding during the withdrawal of the left femoral sheath. At the end of twelve months, 4 patients were asymptomatic and the others were clinically controlled. There were two late deaths in the 7th and 11th months. CONCLUSION: The combined use of the intraaortic balloon pump and percutaneous coronary angioplasty in high-risk patients with acute ischemic syndromes provides the necessary hemodynamic stability to successfully perform the procedures.