Síntese e caracterização de ferritas de manganês e zinco visando aplicação como agente de contraste em diagnóstico médico (biosusceptometria de corrente alternada)

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

Contribuição do estudo ultrassonográfico (Modo e Doppler) de órgãos abdominais em gatos do mato (Leopardus tigrinus) híbridos: valores de referência

Pós-graduação em Medicina Veterinária - FMVZ

Bomba injetora de contraste para angiografia intraoperatória

Refere-se a presente invenção a uma bomba injetora de contraste penumática, estéril e descartável, em plástico, que compreende base em "U" para fixação da seringa propulsora e seringa injetora alinhadas em posição com os respectivos êmbolos em contato.

The role of B-mode ultrasonography in the musculoskeletal anatomical evaluation of the cervical region of the dog spine

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A aquisição do contraste /t/ e /k/ sob a ótica dinâmica

In this article, we present different interpretations to the phenomenon of velar fronting, found in the speech of children. This phenomenon is discussed under both of the following paradigms: the symbolic one – which considers the existence of segments as sources of categorical representations – and the dynamic one, which not only considers different representational units, but also provides an alternative conception of what may be taken as a representation. The analysis focuses on acoustic data produced by children of about three years of age under controlled conditions in a ludic context. The results indicate that the subjects have a covert contrast between alveolars and velars that may be interpreted in light of at least three dynamic hypotheses.

Avaliação do uso de fantomas antropomórficos na análise experimental dos fatores que afetam o contraste de imagens radiográficas

This experimental study aimed the evaluation of the use of anthropomorphic phantoms in the analysis of the influence of the acquisition parameters in the contrast of radiographic images. The analyzed factors were the variation of the peak kilovoltage (kVp) and the product of the filament circuit by the time of exposition (mAs). The influence of these factors was verified for different anthropomorphic phantoms: foot, knee and chest. The image contrast behavior with the simulators was compared to values obtained with the use of an aluminum ladder being the behavior of this reference for analysis and discussion. To assure the reproducibility of images, quality control tests were made and evaluation of procedure conditions before the experiments. The results obtained are shown in a scale of images where it was possible to evaluate the impact in the darkness of images. Regions with different compositions were analyzed which were different in image, this way the values of optical density and contrast are represented as charts and graphics. We conclude that the use of anthropomorphic phantoms in the evaluation of the influence of tension of the tube and time of exposition in the contrast of the radiographic images is not indicated for a quantitative analysis through optical density, once they present incompatible results with the data as reference as the aluminum ladder even so these simulators present a great property in qualitative analysis regarding the differentiation of structures and subjective evaluations

Estudo da dose efetiva, razão sinal-ruído e razão contraste-ruído em tomografia computadorizada de múltiplos detetores

Since discovery, computed tomography is a widely used diagnostic modality. However, this modality imparts relatively high doses to the patients and with fast technological advancement, it is necessary optimize the doses used and ensure the quality of the images through a quality assurance program. This work intended to compare Computed Tomography Dose Index (CTDIW) and effective dose with components of image quality: the Contrast-to-Noise Ratio (CNR) and Signal-to-Noise Ratio (SNR), and a quality factor (Q) deduced by the Rose model for two groups of computed tomography units. The first group was composed by equipments with 10 up to 16 slices and the second one presented 40 up to 320 slices detectors, for the protocols of head and abdomen. It was realized a comparison between different selectable parameters in the protocol of a Philips Brilliance 16, too. The results of the first group to CTDIW, effective dose, SNR and CNR showed variations of 28%, 33%, 37% and 32% respectively for head protocol, and 21%, 27%, 43% and 37% respectively for abdomen protocol. The results of the group 2 to CTDIW, effective dose, SNR and CNR showed variations of 15%, 26%, 36% and 34% respectively for the head protocol, and 8%, 13%, 50% and 60% respectively for abdomen protocol. The comparison between both groups demonstrated similar levels of doses impartation to patients though having so many different configurations, if the uncertainties associated with this measurement were considered. The results of the comparison between different parameters in the Philips Brilliance 16 scanner were in agreement with expected

Síntese e caracterização de ferritas de manganês e zinco visando aplicação como agente de contraste em diagnóstico médico

This work aims to synthesize the manganese and zinc ferrite, by the polymeric precursor method, in order to obtain materials with appropriate characteristics for the application in medical diagnosis techniques. The manganese and zinc ferrite powders with the composition of Mn(1-x)ZnxFe2O4, where x=0,23, were prepared and calcined in air at different times and temperatures. The X-ray diffraction (XRD) data show that the sample calcined at 400°C crystallize as ferrite (monophase), but in an inverted spinel structure (high content of iron occupying manganese tetrahedral site and manganese occupying the iron octahedral site). The samples calcined at temperatures between 600°C and 900°C shows the secondary phase of hematite and the sample calcined at 1100oC shows to be monophase in ferrite with normal spinel structure. The monophase powders of ferrite showed a reduction in the surface area and an increasing in the pore size for higher calcination temperatures. The magnetic analysis show that the sample calcined at 400°C presents satisfactory magnetization at room temperature, however, it behaves as diamagnetic material at low temperatures (10K). The powder containing hematite, without the partial substitution of iron ions by manganese, showed to have low transition temperature, and consequently low magnetization at room temperature. The hematite, when partially substituted, provides materials with irregular magnetization at the saturation region. The powder calcined at 1100°C shows high magnetization either at room temperature or low temperature (10K)

Clivagem e construções similares: contraste, foco e ênfase

This paper deals with so called cleft constructions and other similar structures in eight Portuguese varieties, aiming to show that the formal differences correspond to different functional strategies used by the Speaker to achieve his/her communicative intentions, i.e., Focus, Contrast and Emphasis, in accordance with the theory of Functional Discourse Grammar (Hengeveld and Mackenzie, 2008). This study takes as evidence real spoken occurrences extracted from a corpus organized by Linguistic Centre at the University of Lisbon, in partnership with the University of Toulousse Mirail and the University of Provence-Aix-Marseille. The results show the following distribution: cleft construction is a strategy for pragmatic function Contrast marking; Focus-ser constructions are used to highlight a constituent and (é) que is used as an operator of emphasis showing the speaker’s desire to intensify certain pieces of information.

Estabelecimento do contraste entre as fricativas por crianças com transtorno fonológico: manipulação de pistas acústicas

The present study focuses on the presence of covert contrasts in the speech of children with a phonological disorder. The hypothesis is that children with phonological disorders manipulate secondary acoustic cues in an attempt to distinguish the phonological contrasts. We used five audio recordings of the speech of five children with speech disorders, between four and five years of age, who showed the so-called “phonic substitution” involving the sound group of the fricatives. The data were edited and analyzed using the software PRAAT. A phonetic transcription of the first repetition of each child was performed by three evaluators, reaching a 66% agreement level. After the transcription, we carried out a contrastive phonological analysis of the production of the five children and, finally, an acoustic analysis of all the “substitutions”, based on six parameters. We discovered the existence of covert contrasts in the productions auditorily regarded as homophones by the evaluators, representing a total of 54% of total substitutions identified through an impressionistic approach by the evaluators. Children with phonological disorders are seen to rely on secondary acoustic cues in an attempt to distinguish fricative phonemes. The data obtained in this study allow us to reflect on the importance of considering the phonetic detail within the phonological models.

Estudo mielográfico comparativo entre meios de contraste iopamidol e ioexol em bezerros

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)