Spelling suggestions: "subject:"ultrasound,"" "subject:"ltrasound,""
511 |
Ultrasound Modulation of the Central and Peripheral Nervous SystemJanuary 2015 (has links)
abstract: Noninvasive neuromodulation could help treat many neurological disorders, but existing techniques have low resolution and weak penetration. Ultrasound (US) shows promise for stimulation of smaller areas and subcortical structures. However, the mechanism and parameter design are not understood. US can stimulate tail and hindlimb movements in rats, but not forelimb, for unknown reasons. Potentially, US could also stimulate peripheral or enteric neurons for control of blood glucose.
To better understand the inconsistent effects across rat motor cortex, US modulation of electrically-evoked movements was tested. A stimulation array was implanted on the cortical surface and US (200 kHz, 30-60 W/cm2 peak) was applied while measuring changes in the evoked forelimb and hindlimb movements. Direct US stimulation of the hindlimb was also studied. To test peripheral effects, rat blood glucose levels were measured while applying US near the liver.
No short-term motor modulation was visible (95% confidence interval: -3.5% to +5.1% forelimb, -3.8% to +5.5% hindlimb). There was significant long-term (minutes-order) suppression (95% confidence interval: -3.7% to -10.8% forelimb, -3.8% to -11.9% hindlimb). This suppression may be due to the considerable heating (+1.8°C between US/non-US conditions); effects of heat and US were not separable in this experiment. US directly evoked hindlimb and scrotum movements in some sessions. This required a long interval, at least 3 seconds between US bursts. Movement could be evoked with much shorter pulses than used in literature (3 ms). The EMG latency (10 ms) was compatible with activation of corticospinal neurons. The glucose modulation test showed a strong increase in a few trials, but across all trials found no significant effect.
The single motor response and the long refractory period together suggest that only the beginning of the US burst had a stimulatory effect. This would explain the lack of short-term modulation, and suggests future work with shorter pulses could better explore the missing forelimb response. During the refractory period there was no change in the electrically-evoked response, which suggests the US stimulation mechanism is independent of normal brain activity. These results challenge the literature-standard protocols and provide new insights on the unknown mechanism. / Dissertation/Thesis / Doctoral Dissertation Bioengineering 2015
|
512 |
Neuromodulation of Peripheral Nerve Excitability Using UltrasoundJanuary 2016 (has links)
abstract: The use of a non-invasive form of energy to modulate neural structures has gained wide spread attention because of its ability to remotely control neural excitation. This study investigates the ability of focused high frequency ultrasound to modulate the excitability the peripheral nerve of an amphibian. A 5MHz ultrasound transducer is used for the study with the pulse characteristics of 57msec long train burst and duty cycle of 8% followed by an interrogative electrical stimulus varying from 30μsecs to 2msecs in pulse duration. The nerve excitability is determined by the compound action potential (CAP) amplitude evoked by a constant electrical stimulus. We observe that ultrasound's immediate effect on axons is to reduce the electrically evoked CAP amplitude and thereby suppressive in effect. However, a subsequent time delayed increased excitability was observed as reflected in the CAP amplitude of the nerve several tens of milliseconds later. This subsequent change from ultrasound induced nerve inhibition to increased excitability as a function of delay from ultrasound pulse application is unexpected and not predicted by typical nerve ion channel kinetic models. The recruitment curve of the sciatic nerve modified by ultrasound suggests the possibility of a fiber specific response where the ultrasound inhibits the faster fibers more than the slower ones. Also, changes in the shape of the CAP waveform when the nerve is under the inhibitive effect of ultrasound was observed. It is postulated that these effects can be a result of activation of stretch activation channels, mechanical sensitivity of the nerve to acoustic radiation pressure and modulation of ion channels by ultrasound.
The neuromodulatory capabilities of ultrasound in tandem with electrical stimulation has a significant potential for development of neural interfaces to peripheral nerve. / Dissertation/Thesis / Masters Thesis Bioengineering 2016
|
513 |
Clarinet Multiphonics: A Catalog and Analysis of Their Production StrategiesJanuary 2018 (has links)
abstract: Clarinet multiphonics have become increasingly popular among composers since they were first introduced in the 1950s. However, it is a topic poorly understood by both performers and composers, which sometimes leads to the use of acoustically impossible multiphonics in compositions. Producing multiphonics requires precise manipulations of embouchure force, air pressure, and tongue position. These three factors are invisible to the naked eye during clarinet performance, leading to many conflicting theories about multiphonic production strategies, often based on subjective perception of the performer. This study attempts to observe the latter factor—tongue motion—during multiphonic production in situ using ultrasound. Additionally, a multiphonic catalog containing 604 dyad multiphonics was compiled as part of this study. The author hypothesized that nearly all, if not all, of the multiphonics can be produced using one of four primary production strategies. The four production strategies are: (A) lowering the back of the tongue while sustaining the upper note; (B) raising the back of the tongue while sustaining the upper note; (C) changing the tongue position to that of the lower note while sustaining the upper note; and (D) raising the root of the tongue (a sensation similar to constricting the throat) while sustaining the upper note. To distill production strategies into four primary categories, the author documented his perceived tongue motion over twenty repetitions of playing every multiphonic in the catalog. These perceptions were then confirmed or corrected through ultrasound investigation sessions after every five repetitions. The production strategies detailed in this study are only for finding the correct voicing to produce the multiphonics. The catalog compiled during this study is organized using two different organizational systems: the first uses the traditional method of organizing by pitch; the second uses a fingering-based system to facilitate the ease of finding multiphonics in question, since notated pitches of multiphonics often differ between sources. / Dissertation/Thesis / Doctoral Dissertation Music 2018
|
514 |
Contribution au diagnostic d'empilements PEMFC par spectroscopie d'impédance électrochimique et méthodes acoustiques / Non intrusive diagnostic tools for PEMFCTant, Sylvain 18 July 2013 (has links)
Les piles à combustible constituent une alternative aux moteurs thermiques utilisés dans le cadre d’applications transport ou dans le cadre d’applications stationnaires. Cependant, il existe encore aujourd’hui des verrous technologiques limitant leur développement à l’échelle industrielle. Un des verrous importants est la détermination de leur état de santé en temps réel permettant un diagnostic voire un pronostic de leurs dysfonctionnements ou de leur temps de bon fonctionnement. Dans ce travail, deux approches différentes ont été abordées en vue de proposer des outils de diagnostic pour des empilements de taille industrielle : une approche électrochimique et une approche acoustique. Dans un premier temps, un modèle simple de spectroscopie d’impédance électrochimique et un algorithme d’identification des paramètres ont été développés dans l’optique de proposer un outil de diagnostic rapide et facile à implémenter. Dans un second temps, deux méthodes basées sur la propagation des ondes sonores (l’émission acoustique et les acousto-ultrasons) ont été testées et évaluées dans des conditions de fonctionnement optimales et dégradées. / Fuel cells are a promising alternative to classical fossil energy based engines used in transport applications and electro-generators. However, there still exist limitations preventing it to be used at an industrial scale. In particular, the real-time determination of the cell’s state of health, allowing one to establish a diagnosis or a prognosis of the malfunctions and failures In this document, two different approaches are tested in order to propose real-diagnostic tools for industrial scale stacks. First, a simple electrochemical impedance spectroscopy model is developed in order to create a fast and easily embeddable diagnostic tool. Finally, two techniques based on ultrasound propagation (acoustic emission and acousto-ultrasound).are tested and evaluated in optimal and degraded conditions.
|
515 |
Efeitos da aplicação do ultra-som de baixa intensidade na retração de caninosZavaglia Neto, Regynaldo [UNESP] 10 May 2004 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:55Z (GMT). No. of bitstreams: 0
Previous issue date: 2004-05-10Bitstream added on 2014-06-13T20:57:11Z : No. of bitstreams: 1
zavaglia_neto_r_me_arafo.pdf: 607892 bytes, checksum: ce4a2b46c52e9f11330e30627f4df2bc (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho busca avaliar na movimentação ortodôntica os efeitos de uma tecnologia chamada Ultra-Som de Baixa Intensidade, que produz alterações à nível celular nos tecidos aplicados, permitindo maximizar as respostas da remodelação óssea. As comprovações em animais já indicam a possibilidade de potencializar a movimentação ortodôntica, fazendo a aplicação durante 20 minutos diários. Para a avaliação com seres humanos, dez pacientes Classe II divisão 1 que necessitavam de extração dos primeiros pré-molares superiores foram selecionados. Após a extração e sequência dos arcos de alinhamento e nivelamento, foi realizada a retração parcial dos caninos superiores com molas de NiTi com força de 150 gramas. Neste dia os pacientes foram radiografados para a obtenção das telerradiografias 45º iniciais do lado direito e esquerdo. Após oito semanas de aplicação diária do Ultra-Som no lado sorteado, os pacientes foram novamente radiografados e obtivemos as telerradiografias 45º finais do lado direito e esquerdo. A partir disso, cefalogramas das telerradiografias iniciais e finais foram gerados e avaliados em um programa de cefalometria computadorizado. Tivemos variáveis que avaliaram angulação, deslocamento horizontal e vertical do lado que recebeu ultra-som (LUS) e do lado controle (LC). Após análise estatística, onde testes t de Student foram aplicados, percebemos a tendência dos caninos que receberam a aplicação do ultra-som de baixa intensidade, movimentar mais que os do lado controle. Outro aspecto foi ótimo controle de ancoragem que conseguimos com a força de 150 gramas de força e do uso da barra palatina. / The aim of this research is to evaluate the effects in orthodontic movement of the Low Intensity Ultrasond technology, which produces alterations on cellular level in the applied tissues, allowing the maximization of the bone remodeling response. Experimental studies in animals have already indicated the possibility to potencialize the orthodontic movement with twenty minutes daily ultrasound application. In order to evaluate its effect on human beings, ten Class II division 1 patients with the need of upper first premolars extraction were selected. After the upper premolars extraction and leveling and alignment of the archs, an upper canine partial retraction was obtained with NiTi coil spring delivering a force of 150g. Immediately after the installation of the springs, right and left 45º cephalometric radiographs were taken. After 8 weeks of daily application of ultrasound on the selected side, the final right and left 45º cephalometric radiographs were obtained. Then, initial and final cephalograms were traced and evaluated by a cephalometric software. We evaluated angulation and horizontal and vertical dislocation variables of either the ultrasound side (USS) or the control side (CS). After statistic analysis in a wich a t Student test was performed, we observed the tendency of increased movement of the experimental canines when compared to the control ones. Another important aspect was the good anchorage control obtained by the transpalatal arch use when a 150g force was applied.
|
516 |
Produção leiteira em cabras da raça Saanen: influência dos hormônios cortisol e IGF-IDelgado, Thiago Ferreira Gonçalves [UNESP] 08 December 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:23Z (GMT). No. of bitstreams: 0
Previous issue date: 2008-12-08Bitstream added on 2014-06-13T20:58:01Z : No. of bitstreams: 1
delgado_tfg_me_jabo.pdf: 1053821 bytes, checksum: 151e3e8ed68856f56009d9bdde539d85 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A seleção de animais mais precoces e produtivos, e a melhoria da qualidade do leite são os principais objetivos dos caprinocultores. Com o objetivo de avaliar a interação de dois importantes hormônios, o Cortisol (CORT) e o Fator de Crescimento Análogo à Insulina -1 (IGF-1) na lactação, e suas possíveis influências no desenvolvimento da glândula mamária, produção e qualidade do leite, 38 cabritas (na 1ª fase do experimento) e 24 cabras (na 2ª e 3ª fase do experimento) Saanen divididas em quatro grupos (G1- tratadas com GH e desafiadas com ACTH; G2 – tratadas com GH e desafiadas com placebo; G3 – tratadas com placebo e desafiadas com ACTH; e G4 – tratadas com placebo e desafiadas com placebo). Ao longo de todo experimento foram realizadas coletas de sangue pontuais e durante os desafios, medidas morfométricas internas e externas de úbere e tetos foram realizadas e análises da composição do leite. Não houve diferença no desenvolvimento de úbere e tetos entre animais tratados e não tratados com GH, porém houve maior produção de leite pelos animais tratados, confirmando a eficiência do hormônio em promover maior persistência de lactação. Também houve uma resposta antagônica do IGF-1 ao CORT, durante o desafio das cabras na 3ª fase do experimento, resultado que pode indicar que animais adultos tratados com GH são menos suscetíveis ao estresse que os animais não tratados. O desafio com ACTH e o tratamento com GH não alteraram a composição do leite e a contagem de células somáticas. / The selection of early animals and more productives, and improving the quality of milk are the main goals of goat breeders. With the objective of evaluating the interaction of two important hormones, cortisol (CORT) and the Insulin-Like Growth Factor -1 (IGF-1) in milk, and their possible influences on the development of the mammary gland, yield and quality of milk, 38 kid goats (the 1st. phase of the trial) and 24 goats (in the 2nd and 3rd phase of the trial) Saanen divided into four groups (G1- treated with GH (growth hormone) and challenged with ACTH (adrenocorticotropic hormone), G2 - treated with GH and challenged with placebo; G3 - treated with placebo and challenged with ACTH, and G4 - treated with placebo and challenged with placebo). Throughout experiment samples of blood were collected, internal and external morphometric measures of udder and teats reviews were performed and were performed composition of milk. There were not differences in the development of udder and teats of animals treated and not treated with GH, but treated animals showing higher production than non treated goats, confirming the effectiveness of treatment with GH in promoting increase on persistence of lactation. There was also a response of IGF- 1 antagonist to CORT, the challenge of goats during the 3rd phase of the experiment, result that may indicate that adults treated with GH are less susceptible to stress that the animals not treated. The challenge with ACTH and treatment with GH did not alter the composition of milk and somatic cell count.
|
517 |
Ultra-sonografia pré-cirúrgica da lente e do segmento posterior de cães portadores de catarataRodrigues Junior, Emílio Fernandes [UNESP] 25 November 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:42Z (GMT). No. of bitstreams: 0
Previous issue date: 2008-11-25Bitstream added on 2014-06-13T19:09:49Z : No. of bitstreams: 1
rodriguesjunior_ef_me_jabo.pdf: 359523 bytes, checksum: 2c23cc1e2be735e8fdf242ca84017e13 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A ultra-sonografia do segmento posterior do bulbo do olho é procedimento necessário para a avaliação de cães com catarata, que serão submetidos à facectomia, uma vez que a oftalmoscopia não é factível quando há opacificação da lente, notadamente nas cataratas maduras. Foram avaliados 30 cães (56 olhos), machos ou fêmeas, com idade entre 3 a 14 anos, portadores de diferentes tipos de catarata, em estágios variados de evolução. Realizou-se a ecografia nos modos A e B para o exame da lente e do segmento posterior. Clinicamente, diagnosticou-se catarata madura em 41 olhos (73,21%), catarata imatura em 14 olhos (25%) e catarata hipermatura em apenas um caso (1,78%). Verificou-se, ainda, catarata cortical anterior, posterior e nuclear em 12 olhos (21,42%), catarata cortical anterior, posterior, nuclear e capsular posterior em 23 olhos (41,07%), catarata cortical anterior, posterior e capsular posterior em um olho (1,78%), catarata cortical anterior e nuclear em um olho (1,78%), catarata cortical anterior, nuclear e capsular posterior em cinco olhos (8,92%) e catarata cortical anterior em sete dos olhos (12,5%). Diferentes alterações ultra-sonográficas foram observadas no segmento posterior em 26 dos 56 olhos avaliados (46,42%), incluindo alterações como degeneração vítrea (12 olhos, 21,42%), exsudato ou hemorragia (sete olhos, 12,5%), persistência de artéria hialóide (quatro olhos, 7,14%) e sub-luxação do cristalino (três olhos, 5,35%). A partir dos resultados obtidos, reitera-se a relevância em se realizar a ultra-sonografia em pacientes da espécie canina candidatos à facectomia, dado que alterações do segmento posterior do bulbo do olho são de difícil identificação, quando a lente encontra-se opacificada. / The ultrasound inspection of bulb posterior segment of eyes is a necessary procedure for the evaluation of dogs with cataracts, which will be submitted to the surgery extraction, since the ophthalmoscopy is not feasible when there is opacification of the lens, specially in mature cataracts. Thirty dogs were evaluated (56 eyes), males or females, from 3 to 14 years, affected with different types of cataracts in various developing stages. There was an ultrasound A and B in order to examine the lens and the posterior segment. The dogs were clinically diagnosed to the presence of cataract, demonstrating that 41 eyes (73.21%) was mature, 14 eyes (25%) imature and only one case (1.78%) hypermature. It was verified that 12 dogs eyes (21.42%) showed earlier cortical cataracts, posterior and nuclear, 23 eyes (41.07%) capsular earlier cortical cataracts, posterior and nuclear, one eye (1.78%) capsular earlier cortical cataracts and posterior capsular in cortical cataracts and nuclear up in one eye (1.78%), cortical cataracts earlier, nuclear and capsular in five eyes (8.92%) and cortical cataracts in seven previous eyes (12.5%). Changes in ultrasound evaluation were observed in the posterior segment in 26 of the 56 eyes evaluated (46.42%), including changes as vitreous degeneration 12 eyes, (21.42%), exudate or bleeding 7 eyes (12.5%), continuing artery hyaloid 4 eyes (7.14%) and sub dislocation of the lens 3 eyes (5.35%). From the results reaffirms the importance to take place in the ultrasound patients in the species canine candidates for extraction, since changes in the posterior segment of the bulb of the eyes are difficult to identify, when the lens is opacified.
|
518 |
Avaliação ultra-sonográfica da articulação do joelho em equinos da raça Quarto de MilhaCisneros Álvarez, Luis Emiliano [UNESP] 15 December 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:44Z (GMT). No. of bitstreams: 0
Previous issue date: 2008-12-15Bitstream added on 2014-06-13T19:30:12Z : No. of bitstreams: 1
alvarez_lec_me_botfmvz.pdf: 249428 bytes, checksum: f35a467064df28dab9bd15b0a59c7dc4 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Foi realizado estudo ultra-sonográfico de setenta e quatro articulações do joelho de eqüinos da raça Quarto de Milha, com o objetivo de avaliar e mensurar ligamentos, tendões e meniscos. O exame foi feito mediante abordagem sistemática, na qual foram obtidas as medidas de largura, espessura, perímetro e área dos ligamentos colaterais, patelares, meniscos e tendão de origem dos músculos extensor digital longo e fibular terceiro, bem como do recesso medial. Todos os ligamentos apresentaram ecogenicidade uniforme de grau 0. O padrão das fibras foi regular e homogêneo e as margens foram bem definidas. O menisco medial foi observado triangular, com leve concavidade da margem proximal e reto na margem distal. O menisco lateral apresentou-se triangular ou trapezóide e ambas as superfícies (proximal e distal) foram retas. A analise de variância mostrou diferenças significativas entre os valores das medias dos machos e fêmeas na origem dos ligamentos patelares medial e lateral, e tendão dos músculos extensor digital longo e fibular terceiro. Estas estruturas foram maiores em fêmeas que em machos. Na comparação entre membros esquerdos e direitos, foram achadas diferenças significativas na inserção do ligamento patelar intermédio, tendão dos músculos extensor digital longo e fibular terceiro e recesso medial. Os resultados do teste de Pearson mostraram correlação media e alta entre as variáveis de largura, espessura, perímetro e área dos ligamentos, meniscos, e tendão. Porém, não foi observada correlação entre peso com o resto das variáveis. A abordagem ultra-sonográfica sistemática permitiu visualização e mensuração dos tecidos moles do joelho avaliados neste estudo. / Seventy four stifle joints of American Quarter Horses were ultrasonographically imaged in order to evaluate and measure ligaments, tendons and menisci. Ultrasonographic examination was achieved using a systematic approach. Measures of width, thickness, perimeter and area of the femorotibial collateral and patellar ligaments, menisci, tendon of origin of the long digital extensor and peroneus tertius muscles, and medial recess were obtained. The ligaments and tendon had uniform grade-0 echogenicity. Fiber pattern was regular and homogeneous, and margins were well defined. Medial meniscus was triangular shaped, slightly concave at the proximal surface and flat at the distal surface. Lateral meniscus was triangular to trapezoidal and the proximal and distal surfaces were flat. Analysis of variance showed significant differences between mean values of males and females for the origin of the medial and lateral patellar ligaments, as well as tendon of origin of the long digital extensor and peroneus tertius muscles. These structures tended to be larger in females than in males. When comparison was made between left and right hindlimb, significant differences were found for the insertion of the intermediate patellar ligament, tendon of origin of the long digital extensor and peroneus tertius muscles and medial recess. Pearson’s correlation coefficients regarding width, thickness, perimeter and area of the ligaments, menisci, and tendon showed moderate to high correlation between variables. However, correlation between weight and other variables was not observed. Ultrasonography through systematic approach allowed imaging and measurement of the soft tissues of the stifle evaluated herein.
|
519 |
Ultrassonografia convencional e elastografia ARFI (Acoustic Radiation Force Impulse) na avaliação renal de gatos adultos hígidos / ARFI (Acustic Radiaton Force Impulse) elastography in renal evaluation of healthy adult catsGarcia, Paulo Henrique de Souza [UNESP] 13 July 2016 (has links)
Submitted by PAULO HENRIQUE DE SOUZA GARCIA null (paulousvet@gmail.com) on 2016-08-16T11:40:16Z
No. of bitstreams: 1
Ultrassonografia convencional e Elastografia ARFI na aaliação renal e gatos adultos hígidos.pdf: 2204900 bytes, checksum: 6acbf410866645d13616b8dc7610bd26 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-08-16T14:18:14Z (GMT) No. of bitstreams: 1
garcia_phs_me_jabo.pdf: 2204900 bytes, checksum: 6acbf410866645d13616b8dc7610bd26 (MD5) / Made available in DSpace on 2016-08-16T14:18:14Z (GMT). No. of bitstreams: 1
garcia_phs_me_jabo.pdf: 2204900 bytes, checksum: 6acbf410866645d13616b8dc7610bd26 (MD5)
Previous issue date: 2016-07-13 / O exame ultrassonográfico convencional tem baixa especificidade para detecção de alterações difusas, no entanto, o aumento da ecogenicidade renal é um dos achados mais comuns em cães e gatos com nefropatia. O objetivo deste estudo foi descrever a técnica de elastografia por irradiação da força de impulso acústico (ARFI) na avaliação dos rins de gatos adultos hígidos, e determinar os valores de referência. Foram incluídos neste trabalho dez gatos de pelo curto, adultos e saudáveis. Após sedação, foi realizada uma ampla tricotomia abdominal, para a realização do exame ultrassonográfico. O exame convencional, em Modo B foi realizado com um transdutor linear de 9,0 MHz usando equipamento de ultrassom ACUSON S2000 / SIEMENS (Siemens, Munique, Alemanha). A ecogenicidade, ecotextura, o tamanho e contornos renais foram avaliados. Com o mesmo transdutor, a elastografia foi realizada utilizando software para comparação das análises qualitativa e quantitativa do método. A elastografia qualitativa detectou a presença de deformidades e as velocidades de cisalhamento em diferentes locais (cranial, média e caudal) das regiões cortical e medular em ambos os rins. Os achados ultrassonográficos foram considerados normais em todos os gatos, sem alterações em arquitetura ou ecogenicidade renal. A elastografia qualitativa demonstrou que o córtex renal era deformável e apresentou áreas cinza escuro homogêneas; pelve renal tinha pouca rigidez (branca); e da medula mostrou um padrão de mosaico. Os resultados de velocidade de onda de cisalhamento foram diferentes em regiões cranial, média e caudal do córtex e medula: 2,46 m/s ± 0,45 m/s; 2,46m/s ± 0,48 m/s e 2, 37 m/s ± 0, 42 m/s (P = 0,795) no córtex e 1,61 m/s ± 0,69 m/s, 1,75 m/s ± 0,66 m/s e 2,00 m/s ± 0,55 m/s (P = 0,156) na medula, respectivamente. A ARFI quantitativa e qualitativa do rim em gatos adultos foi realizada facilmente e este estudo forneceu valores de referência para a caracterização da normalidade do parênquima renal em gatos hígidos. / Conventional ultrasonography has low specificity to detect diffuse changes, however, increased renal echogenicity is one of the most common findings in dogs and cats with nephropathy. The objective of this study was to describe elastography by acoustic radiation force impulse (ARFI) in the assessment of adult cats' kidneys and determine reference values. Ten healthy adults short hair cats were included. After sedation, abdominal hair was clipped in order to perform ultrasound exams. The conventional examination (B-mode) was performed with a 9.0 MHz linear array transducer ultrasound equipment using ACUSON S2000/Siemens (Siemens, Munich, Germany). Echogenicity, echotexture, size and contours of each kidney were evaluated. With the same transducer, elastography was performed using a software that compares qualitative and quantitative analysis. Qualitative elastography detected deformities and shear wave velocity rates in different portions (cortical and medulla' cranial, media and caudal regions). The sonographic findings were normal in all cats, with no changes in renal architecture or echogenicity. Qualitative elastography showed that renal cortex was softer with dark gray homogeneous areas; renal pelvis presented lower stiffness (white); and medulla showed a mosaic pattern. Shear wave velocities were obtained in cranial, medial, and caudal regions of the cortex and medulla: 2.46 m/s ± 0.45m/s; 2,46m/s ± 0.48 m/ s 2,37 m/s ± 0, 42 m/s (P = 0.795) in the cortex and 1.61 m/s ± 0.69 m/s 1.75 m/s ± 0.66 m/s and 2.00m/s ± 0.55m/s (P = 0.156) in medulla, respectively. Quantitative and qualitative ARFI kidney in adult cats was easily accomplished and this study was able to provide values for the characterization of the normal renal parenchyma in healthy cats.
|
520 |
Parâmetros ultrassonográficos do movimento da língua em 14 fonemas consonantais do Português Brasileiro / Ultrasonographic parameters of tongue movement in the production of the 14 consonantal phonemes of Brazilian PortugueseSilva, Lídia Maurício [UNESP] 28 April 2017 (has links)
Submitted by Lidia Mauricio da Silva null (lidiamau_u@hotmail.com) on 2017-05-27T21:44:05Z
No. of bitstreams: 1
DISSERTAÇÃO_DEFESA_pdf .pdf: 1196024 bytes, checksum: 98d43d8f5817e28a58c9769670c2ebc5 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-05-31T14:42:49Z (GMT) No. of bitstreams: 1
silva_lm_me_mar.pdf: 1196024 bytes, checksum: 98d43d8f5817e28a58c9769670c2ebc5 (MD5) / Made available in DSpace on 2017-05-31T14:42:50Z (GMT). No. of bitstreams: 1
silva_lm_me_mar.pdf: 1196024 bytes, checksum: 98d43d8f5817e28a58c9769670c2ebc5 (MD5)
Previous issue date: 2017-04-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Objetivo: O objetivo desse estudo foi propor parâmetros ultrassonográficos quantitativos que pudessem apreender diferenças de modo e ponto de articulação entre os 14 fonemas linguais do Português Brasileiro (doravante PB), buscando estimar valores de referência e um padrão de variabilidade quanto ao contorno de superfície de língua na produção de fala típica. Métodos: Foram selecionados 20 sujeitos com produção típica de fala, de 20-30 anos, de ambos os gêneros. Os estímulos selecionados contemplaram os 14 fonemas consonantais linguais do PB no contexto da vogal /a/. Os dados foram coletados e analisados com o uso do ultrassom e dos softwares AAA (Articulate Assistant Advanced) e Ultra- CATS (The Ultrasonographic Contour Analyzer for Tongue Surfaces). Para análise dos dados, um índice ultrassonográfico (US) foi selecionado da literatura já existente: índice de anterioridade (IA), enquanto outros dois foram desenvolvidos no presente estudo: média global (MG) e índice de anterioridade normalizado (IAN). Os dados foram submetidos à análise estatística. Resultados: A ANOVA mostrou efeito significante para os índices IAN e MG, sendo que o IAN diferenciou os fonemas quanto ao ponto (alveolar, pré-palatal, palatal e velar) e modo de articulação (fricativa, nasal e oclusiva), enquanto o MG diferenciou os fonemas somente quanto ao ponto de articulação (alveolar, pré-palatal e velar). Conclusão: Não houve um único índice US que pudesse diferenciar todos os pontos e modos de articulação simultaneamente. A aplicação clínica para análise das alterações da produção da fala requer o uso de pelo menos dois índices ultrassonográficos: um para distinguir o ponto e outro para distinguir o modo de articulação. Por fim, tendo por princípio que os fonemas consonantais apresentam variabilidade fonêmica e que exigem a produção concomitante e coordenada de diferentes gestos articulatórios, incluindo o movimento do véu palatino, direcionando o fluxo de ar no trato vocal, novas medidas em plano coronal da língua poderiam oferecer subsídio para complementar a caracterização ultrassonográfica dos fonemas nasais e líquidos. / Objective: The aim of this study was to propose quantitative ultrasonographic parameters that could detect differences in the manner and place of articulation among the 14 Brazilian Portuguese phonemes (hereinafter BP), seeking to estimate reference values and a pattern of variability regarding the surface contour of the tongue in typical speech production. Methods: We selected 20 subjects with typical speech production, aged between 20-30 years, of both genders. The selected stimuli include the 14 lingual consonant BP phonemes in the intervocalic context of [a]. Data were collected and analyzed with the use of ultrasound and the AAA (Articulate Assistant Advanced) and the Ultra-CATS (The Ultrasonographic Contour Analyzer for Tongue Surfaces) softwares. For the analysis of the data, an ultrasonographic index (UI) was selected from the existing literature: the index of anteriority (IA), while two others were developed in the present study: the global average (GA) and the index of normalized anteriority (INA). The data were submitted to statistical analysis. Results: ANOVA showed a significant effect on the indexes INA and GA, and the INA index differentiated phonemes as the place (alveolar, pre-palatal, palatal and velar) and manner of articulation (fricative, nasal and occlusive); GA differentiate phonemes only as the place of articulation (alveolar, pre-palatal and velar). Conclusion: There was no UI index that could differentiate all places and manners of articulation simultaneously. The clinical application for analysis of speech production disorders require the use of at least two ultrasound indexes: one to distinguish the place and another to distinguish the manner of articulation. Finally, considering that consonant phonemes present phonemic variability and require the concomitant and coordinated production of different articulatory gestures, including the movement of the palatine veil directing the airflow in the vocal tract, new measures in the coronal plane of the tongue could offer support to complement the ultrasound characterization of nasal and liquid phonemes.
|
Page generated in 0.1121 seconds