253 resultados para Irradiação ultrassônica


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Pós-graduação em Agronomia (Energia na Agricultura) - FCA

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Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB

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Ultrasound is the term that describes the sound waves with higher frequencies than human hearing. Ultrasound used in medical diagnosis is a modality based on the use of sound energy and the acoustic properties of the various parts of the body to produce images of stationary and moving tissues. However, despite the ease of use and security that this modality offers for not using ionizing radiation, one should ensure the accuracy and optimum performance of the equipment, which results in precise diagnoses. To accomplish that, periodic quality control tests must be performed, which include: physical and mechanical inspection of the equipment, image uniformity, depth of penetration/visualization, accuracy of distances, axial and lateral resolution, dead zone and doppler sensitivity. This work intends to study a computerized method for calculating the depth of penetration of ultrasound, comparing it to the observerdependent method currently used. The images were collected during the quality control tests of ultrasound equipment. The results of the comparison between the visual and computerized methods were not conclusive for selecting the safest methodology for obtaining the depth of visualization

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This work intends to investigate the biodegradation of the polymers and blend films of polypropylene (PP) and poly(hidroxybutirate-valerate) (PHBV), after UV radiation to facilitate the PP degradation, which is a polymer with long chains difficult to degrade by biological agents present in the environment. This polymer is outstanding by its mechanical properties and versatility of industrial and commercial use and the PHBV by its quick biodegradability in the environment. Blends of these materials could to present a commitment between mechanical properties and biodegradability to execute its function and after the discard to have lesser lifetime in the garbage landfills. Another aspect of this work is the controlling effect of PP on PHBV, influencing its degradation time

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O estágio realizado em parceria entre o Departamento de Física e Biofísica do IBB-UNESP e o Hemocentro de Botucatu da FMB-UNESP teve como objetivo desenvolver um novo equipamento de luz LED capaz de interagir com culturas celulares. Desta forma foi desenvolvido um equipamento com luz azul e luz vermelha. A luz azul é responsável por inibir o crescimento celular, a luz vermelha é responsável por aumentar o crescimento celular. O equipamento consiste de uma fonte, e dois conjuntos com três LEDs cada. A cultura celular escolhida foi a de Miemola Murino (NS1), uma linhagem que possui alta taxa de crescimento e que foi mantida em estufa e meio de cultura, (simulando condições normais de sobrevivência), sendo irradiada três vezes ao dia. As amostras foram coletadas e contadas em câmara de Neubauer. Os resultados obtidos, quando comparados com o controle, não apresentaram significativa diferença de crescimento quando irradiados com luz LED vermelho. Porém quando comparados o grupo controle com o grupo irradiado com LED azul, notou-se uma significativa redução da quantidade de células a partir do sétimo dia de irradiação. Acredita-se que a ineficácia dos LEDs vermelhos ocorreram pois utilizamos células com metabolismo bastante elevado, dificultando um aumento ainda maior da taxa de crescimento. A redução da população de células azuis ocorre pois a radiação interage com a membrana celular, causando a quebra dessa membrana e conseqüente morte da célula. Outra via para a morte é a lesão causada no DNA das células, que ocorre quando a luz azul é absorvida pela molécula

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Nowadays technological trend is based on finding materials that could support low weight with satisfactory mechanical properties and for this reason composite material became a very attractive topic in research projects all over the world. Due to its heterogenic properties, this type of material shows scatter in mechanical test results, especially in cyclic loading. Therefore it is important to predict its fatigue strength behaviour by statistic analysis, once fatigue causes approximately 90% of the failure in structural components. The present work aimed to investigate the fatigue behaviour of the Twill/Cycom 890 composite, which is carbon fiber reinforced with polymeric resin as matrix and manufactured via RTM process (Resin Transfer Molding). All samples were tested in different tensile level in triplicate in order to associate these values. The statistical analysis was conducted with Two-Parameter Weibull Distribution and then evaluated the fatigue life results for the composite. Weibull graphics were used to determine the scale and shape parameters. The S-N curve for the Twill/Cycom composite was drawn and indicated the number of cycles to occur the first damages in this material. The probability of failure was associated with material reliability, as shown in graphics for the different tensile levels and fatigue life. In addition, the laminate was evaluated by ultrasonic inspection showing a regular impregnation. The fractographic analysis conducted by SEM showed failure mechanisms for polymeric composites associated to cyclic loadings ... (Complete abstract click electronic access below)

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O estudo objetivou apresentar uma revisão bibliográfica sobre a filogenia, evolução, comportamentos reprodutivos e a evolução do cuidado parental em peixes da família Cichlidae, com ênfase em Cichlinae (ciclídeos Neotropicais). Atualmente a filogenia do grupo tem confirmado o monofiletismo da subfamília Etroplinae (India, Sri Lanka e Madagascar) como grupo irmão dos demais ciclídeos. Ptychochrominae (Madagascar) também monofilética é considerada grupo irmão dos clados Cichlinae (neotropicais) e Pseudocrenilabrinae (africanos), sendo os últimos clados irmãos entre si. Em relação às estratégias reprodutivas dos Cichlidae pode-se dividi-los quanto sua incubação em: Incubadores bucais (mouth-brooders), incubadores de substrato (substrate-spawners) e incubadores bucais tardios (mouth-brooders tardios), tais características podem nos oferecer embasamento para a compreensão das condições pelas quais as diferentes formas de cuidado parental e métodos de acasalamento evoluíram. O estudo enfatiza os comportamentos reprodutivos e cuidados parentais nos Cichlinae, descrevendo comportamentos que auxiliam na compreensão da biologia reprodutiva do grupo e sugerindo hipóteses sobre a origem e irradiação dos Cichlidae

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The Boron Neutron Capture Therapy (BNCT), based on the 10B(n,α)7Li reaction, represents a promising modality for the treatment of cancers that are resistents to conventional treatments. So, it is necessary to find drugs (boron compounds) with high selectivity for each type of cancer, the neutrons source should be well characterized and the rate of 10B(n,α)7Li reaction should be measured with great accuracy as possible. This study aimed to develop a method for manufacturing thin films of boron, for measure the 10B(n,α)7Li reaction, and analyze the uniformity of the films. Five thin films of boron were manufactured with three different concentrations of boric acid, heated to transform the acid in boron, irradiated with thermic neutrons coupled to CR-39 detectors, in BNCT line at the reactor IEA-R1 IPEN/CNEN, São Paulo. After the irradiation, the detectors were chemically attacked with NaOH to reveal the tracks. The methodology presented is effective because it resulted in deposition of boron as thin film enabling the quantitative analysis of 10B(n,α)7Li reaction. The analysis of the uniformity of density of the induced tracks in CR-39 shows that, in most of the films, there is no uniformity in surface distribution of boron, but when the film is divided, we obtain some uniform sectors