489 research outputs found
Composição botùnica da dieta consumida por bovinos em pastagens de quicuio-da-amazÎnia (Brachiaria humidicola) e braquiarão (Brachiaria brizantha), consorciadas com essenciais florestais, com ou sem queima.
The human otitis media with effusion: a numerical-based study
Otitis media is a group of inflammatory diseases of the middle ear. Acute otitis media and otitis media with effusion (OME) are its two main types of manifestation. Otitis media is common in children and can result in structural alterations in the middle ear which will lead to hearing losses. This work studies the effects of an OME on the sound transmission from the external auditory meatus to the inner ear. The finite element method was applied on the present biomechanical study. The numerical model used in this work was built based on the geometrical information obtained from The visible ear project. The present work explains the mechanisms by which the presence of fluid in the middle ear affects hearing by calculating the magnitude, phase and reduction of the normalized umbo velocity and also the magnitude and phase of the normalized stapes velocity. A sound pressure level of 90Â dB SPL was applied at the tympanic membrane. The harmonic analysis was performed with the auditory frequency varying from 100Â Hz to 10Â kHz. A decrease in the response of the normalized umbo and stapes velocity as the tympanic cavity was filled with fluid was obtained. The decrease was more accentuated at the umbo.info:eu-repo/semantics/publishedVersio
Study of the middle ear behavior considering the presence of fluid
O objetivo deste trabalho foi estudar a influĂȘncia de diferentes fluidos dentro e fora da cavidade timpĂąnica no comportamento biomecĂąnico do ouvido mĂ©dio. O modelo computacional 3 D da cadeia tĂmpanoâossicular foi construĂdo atravĂ©s de imagens de tomografia axial computorizada (TAC). ApĂłs a construção do modelo da cadeia tĂmpanoâossicular, para a parte interna da membrana timpĂąnica foi criada a caixa timpĂąnica, que inclui toda a cadeia ossicular, e para a parte externa da membrana foi criada uma passagem, simulando o canal auditivo externo.
A discretização do modelo foi feita utilizando o mĂ©todo dos elementos finitos, com base no software ABAQUS. As propriedades mecĂąnicas foram extraĂdas de trabalhos anteriores. Foram obtidos os deslocamentos do umbo e de um ponto central da platina do estribo, para um nĂvel de pressĂŁo sonora de 105 dB aplicada na membrana timpĂąnica, comparando a cadeia tĂmpanoâossicular e os diferentes nĂveis de pressĂŁo externa e interna do ouvido mĂ©dio (fluido lĂquido e fluido gasoso). Os resultados demonstram que o comportamento biomecĂąnico do ouvido mĂ©dio Ă© diferente para os diferentes nĂveis de pressĂ”es testadas neste modelo. Quando utilizada uma pressĂŁo de fluido lĂquido, os deslocamentos sĂŁo de amplitude inferior quando comparados com os resultados obtidos com pressĂŁo de ar.The objective of this work is to study the influence of different fluids of the tympanic cavity into the biomechanical behavior of the middle ear. The 3 D computer model of the tympanic ossicular chain was built using images from computed tomography (CT). After construction of the tympanic ossicular chain model, it was adapted the simulation by placing the passage to the external auditory canal and to the tympanic cavity.
The discretization of the model was made using the finite element method based on ABAQUS software. The mechanical properties were extracted from previous works. The umbo and the stapes footplate displacements, for a sound pressure level of 105 dB applied in tympanic membrane were obtained, comparing the tympanic ossicular chain and the different levels of external and internal pressure in the middle ear (liquid and air). The results demonstrate that the biomechanical behavior of the middle ear is different for different levels of pressure tested in this model. When using liquid, displacements are of lower amplitude when compared with the results obtained with air.Peer Reviewe
EP-1184: Hypofractionated simultaneous integrated boost radiotherapy after breast-conserving surgery: 3 years follow-up
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Perguntas e respostas sobre o Termo de Compromisso de Ajustamento de Condutas da Suinocultura - TAC.
bitstream/item/57780/1/CUsersPiazzonDocumentsCartilha-TAC.pd
Oval Domes: History, Geometry and Mechanics
An oval dome may be defined as a dome whose plan or profile (or both) has an oval form. The word Aoval@ comes from the latin Aovum@, egg. Then, an oval dome has an egg-shaped geometry. The first buildings with oval plans were built without a predetermined form, just trying to close an space in the most economical form. Eventually, the geometry was defined by using arcs of circle with common tangents in the points of change of curvature. Later the oval acquired a more regular form with two axis of symmetry. Therefore, an âovalâ may be defined as an egg-shaped form, doubly symmetric, constructed with arcs of circle; an oval needs a minimum of four centres, but it is possible also to build polycentric ovals.
The above definition corresponds with the origin and the use of oval forms in building and may be applied without problem until, say, the XVIIIth century. Since then, the teaching of conics in the elementary courses of geometry made the cultivated people to define the oval as an approximation to the ellipse, an âimperfect ellipseâ: an oval was, then, a curve formed with arcs of circles which tries to approximate to the ellipse of the same axes. As we shall see, the ellipse has very rarely been used in building.
Finally, in modern geometrical textbooks an oval is defined as a smooth closed convex curve, a more general definition which embraces the two previous, but which is of no particular use in the study of the employment of oval forms in building.
The present paper contains the following parts: 1) an outline the origin and application of the oval in historical architecture; 2) a discussion of the spatial geometry of oval domes, i. e., the different methods employed to trace them; 3) a brief exposition of the mechanics of oval arches and domes; and 4) a final discussion of the role of Geometry in oval arch and dome design
Altered organization of the intermediate filament cytoskeleton and relocalization of proteostasis modulators in cells lacking the ataxia protein sacsin
This work was supported by BBSRC [BB/L02294X/1]; the CIHR Rare Disease Emerging Team
grant, the Ataxia of Charlevoix-Saguenay Foundation; Muscular Dystrophy Canada and Barts and
the London Charity [417/1699]. The LSM880 confocal used in these studies was purchased
through a Barts and the London Charity grant MGU0293
Coincidence measurement of residues and light particles in the reaction 56Fe+p at 1 GeV per nucleon with SPALADIN
The spallation of Fe in collisions with hydrogen at 1 A GeV has been
studied in inverse kinematics with the large-aperture setup SPALADIN at GSI.
Coincidences of residues with low-center-of-mass kinetic energy light particles
and fragments have been measured allowing the decomposition of the total
reaction cross-section into the different possible de-excitation channels.
Detailed information on the evolution of these de-excitation channels with
excitation energy has also been obtained. The comparison of the data with
predictions of several de-excitation models coupled to the INCL4 intra-nuclear
cascade model shows that only GEMINI can reasonably account for the bulk of
collected results, indicating that in a light system with no compression and
little angular momentum, multifragmentation might not be necessary to explain
the data.Comment: 4 pages, 5 figures, revised version accepted in Phys. Rev. Let
Discriminant Analysis and Secondary-Beam Charge Recognition
The discriminant-analysis method has been applied to optimize the exotic-beam
charge recognition in a projectile fragmentation experiment. The experiment was
carried out at the GSI using the fragment separator (FRS) to produce and select
the relativistic secondary beams, and the ALADIN setup to measure their
fragmentation products following collisions with Sn target nuclei. The beams of
neutron poor isotopes around 124La and 107Sn were selected to study the isospin
dependence of the limiting temperature of heavy nuclei by comparing with
results for stable 124Sn projectiles. A dedicated detector to measure the
projectile charge upstream of the reaction target was not used, and alternative
methods had to be developed. The presented method, based on the multivariate
discriminant analysis, allowed to increase the efficacy of charge recognition
up to about 90%, which was about 20% more than achieved with the simple scalar
methods.Comment: 6 pages, 7 eps figures, elsart, submitted to Nucl. Instr. and Meth.
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