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2.
Ultrason Sonochem ; 38: 62-74, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28633858

RESUMEN

The use of water in subcritical conditions for extraction has several drawbacks. These include the safety features, higher production costs and possible degradation of the bioactive compounds. To overcome these problems, sonic energy and an entrainer were used as external interventions to decrease the polarity of water at milder operating conditions. The effect of low (28kHz) and high (800kHz) frequencies of sonication in the extraction of the main ginger bioactive compound (6-gingerol) were compared. Six parameters were studied: mean particle size (MPS, mm), time of extraction, applied power, sample to solvent ratio (w/v), temperature of extraction, and the percentage of entrainer. The optimum conditions for high frequency SAWE prototype were MPS 0.89-1.77mm, 45min, 40W applied power, 1:30 (w/v), 45°C, and 15% of ethanol as entrainer. Two-way analysis of variance (ANOVA) gave the most significant parameter, which was power with F (1, 45.07), p<2.50×10-9. Although the effect of low frequency was stronger than high frequency, at the optimum conditions of the sample to solvent ratio 1:30 (w/v) with 700mL solvent and temperature 45°C, the concentration and recovery of 6-gingerol from high frequency of SAWE prototype was 2.69 times higher than at low frequency of SAWE. It was found that although the effects of high frequency (800kHz) were negligible in other studies, it could extract suitable compounds, such as 6-gingerol, at lower temperature. Therefore, the effects of sonication, which cause an enlargement in the cell wall of the ginger plant matrix, were observed using a Scanning Electron Microscope (SEM). It was found that the applied power of sonication was the most significant parameter compared to the other parameters.

3.
Front Psychol ; 6: 1219, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26347686

RESUMEN

We propose an expression transmission system using a cellular-phone-type teleoperated robot called Elfoid. Elfoid has a soft exterior that provides the look and feel of human skin, and is designed to transmit the speaker's presence to their communication partner using a camera and microphone. To transmit the speaker's presence, Elfoid sends not only the voice of the speaker but also the facial expression captured by the camera. In this research, facial expressions are recognized using a machine learning technique. Elfoid cannot, however, display facial expressions because of its compactness and a lack of sufficiently small actuator motors. To overcome this problem, facial expressions are displayed using Elfoid's head-mounted mobile projector. In an experiment, we built a prototype system and experimentally evaluated it's subjective usability.

4.
J Radiat Res ; 55(5): 1015-20, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24944266

RESUMEN

The feasibility of single isocenter, multi-arc non-coplanar volumetric modulated arc therapy (VMAT) for multiple brain tumors was studied using an Elekta Synergy linear accelerator with an Agility multileaf collimator and a Monaco treatment planning system. Two VMAT radiosurgery plans consisting of a full arc and three half arcs were created with a prescribed dose of 20 Gy in a single fraction. After dose delivery to a phantom, ionization chambers and radiochromic films were used for dose measurement. The first VMAT radiosurgery plan had nine targets inside the phantom, and the doses were measured by the chambers at two different points and by the films on three sagittal and three coronal planes. The differences between the calculated dose and the dose measured by a Farmer ionization chamber and a pinpoint ionization chamber were <1.00% and <2.30%, respectively, and the average pass rates of gamma indices among the six planes under each of 3%/3 mm and 2%/2 mm criteria were 98.6% and 92.6%, respectively. The second VMAT radiosurgery plan was based on a clinical 14 brain metastases. Differences between calculated and film-measured doses were evaluated on two sagittal planes. The average pass rates of the gamma indices on the planes under each of 3%/3 mm and 2%/2 mm criteria were 97.8% and 88.8%, respectively. It was confirmed that single-isocenter, non-coplanar multi-arc VMAT radiosurgery for multiple brain metastases was feasible using Elekta Synergy with Agility and Monaco treatment planning systems. It was further shown that film dosimetry was accurately performed for a dose of up to nearly 25 Gy.


Asunto(s)
Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/cirugía , Aceleradores de Partículas/instrumentación , Radiocirugia/instrumentación , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/instrumentación , Radioterapia de Intensidad Modulada/métodos , Neoplasias Encefálicas/diagnóstico por imagen , Diseño de Equipo , Análisis de Falla de Equipo , Estudios de Factibilidad , Humanos , Fantasmas de Imagen , Radiocirugia/métodos , Dosificación Radioterapéutica , Tomografía Computarizada por Rayos X/instrumentación , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento
6.
J Radiat Res ; 54(1): 152-6, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22843380

RESUMEN

We propose a clinical workflow of stereotactic volumetric modulated arc therapy (VMAT) for a lung tumor from planning to tumor position verification using 4D planning computed tomography (CT) and 4D cone-beam CT (CBCT). A 4D CT scanner, an Anzai belt and a BodyFix were employed to obtain 10-phase respiratory-correlated CT data for a lung patient under constrained breathing conditions. A planning target volume (PTV) was defined by adding a 5-mm margin to an internal target volume created from 10 clinical target volumes, each of which was delineated on each of the 10-phase planning CT data. A single-arc VMAT plan was created with a D(95) prescription dose of 50 Gy in four fractions on the maximum exhalation phase CT images. The PTV contours were exported to a kilovoltage CBCT X-ray Volume Imaging (XVI) equipped with a linear accelerator (linac). Immediately before treatment, 10-phase 4D CBCT images were reconstructed leading to animated lung tumor imaging. Initial bone matching was performed between frame-averaged 4D planning CT and frame-averaged 4D CBCT datasets. Subsequently, the imported PTV contours and the animated moving tumor were simultaneously displayed on the XVI monitor, and a manual 4D registration was interactively performed on the monitor until the moving tumor was symmetrically positioned inside the PTV. A VMAT beam was delivered to the patient and during the delivery further 4D CBCT projection data were acquired to verify the tumor position. The entire process was repeated for each fraction. It was confirmed that the moving tumor was positioned inside the PTV during the VMAT delivery.


Asunto(s)
Tomografía Computarizada Cuatridimensional/métodos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/radioterapia , Radiocirugia/métodos , Radioterapia Guiada por Imagen/métodos , Radioterapia de Intensidad Modulada/métodos , Técnicas de Imagen Sincronizada Respiratorias/métodos , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Técnica de Sustracción
7.
Radiat Oncol ; 7: 20, 2012 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-22315950

RESUMEN

BACKGROUND: The purpose of this study was to compare dose distributions from three different algorithms with the x-ray Voxel Monte Carlo (XVMC) calculations, in actual computed tomography (CT) scans for use in stereotactic radiotherapy (SRT) of small lung cancers. METHODS: Slow CT scan of 20 patients was performed and the internal target volume (ITV) was delineated on Pinnacle3. All plans were first calculated with a scatter homogeneous mode (SHM) which is compatible with Clarkson algorithm using Pinnacle3 treatment planning system (TPS). The planned dose was 48 Gy in 4 fractions. In a second step, the CT images, structures and beam data were exported to other treatment planning systems (TPSs). Collapsed cone convolution (CCC) from Pinnacle3, superposition (SP) from XiO, and XVMC from Monaco were used for recalculating. The dose distributions and the Dose Volume Histograms (DVHs) were compared with each other. RESULTS: The phantom test revealed that all algorithms could reproduce the measured data within 1% except for the SHM with inhomogeneous phantom. For the patient study, the SHM greatly overestimated the isocenter (IC) doses and the minimal dose received by 95% of the PTV (PTV95) compared to XVMC. The differences in mean doses were 2.96 Gy (6.17%) for IC and 5.02 Gy (11.18%) for PTV95. The DVH's and dose distributions with CCC and SP were in agreement with those obtained by XVMC. The average differences in IC doses between CCC and XVMC, and SP and XVMC were -1.14% (p = 0.17), and -2.67% (p = 0.0036), respectively. CONCLUSIONS: Our work clearly confirms that the actual practice of relying solely on a Clarkson algorithm may be inappropriate for SRT planning. Meanwhile, CCC and SP were close to XVMC simulations and actual dose distributions obtained in lung SRT.


Asunto(s)
Algoritmos , Neoplasias Pulmonares/cirugía , Método de Montecarlo , Radiocirugia , Planificación de la Radioterapia Asistida por Computador , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Fantasmas de Imagen , Dosificación Radioterapéutica , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
9.
Biosci Biotechnol Biochem ; 67(6): 1327-34, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12843661

RESUMEN

We found a bacterium that converts sucrose to a useful material, using about 6,000 samples of bacteria isolated from soil. This bacterium, Bacillus sp. 217C-11, was identified according to Bergey's manual, and produced a highly efficient enzyme that converted sucrose into inulin. So, the enzyme was purified to homogeneity through five chromatographic steps, to identify its enzymatic properties. The molecular mass of the enzyme was estimated to be 45,000, and this enzyme was a monomer protein (by SDS-PAGE). The optimum pH and temperature of this enzyme were 7-8 and 45-50 degrees C, respectively. The enzyme reacted only with sucrose, but did not with other disaccharides, fructooligosaccharides and inulin. This paper will show that our enzyme is a novel one, which is different from the other well-known enzymes concerned in inulin production.


Asunto(s)
Bacillus/enzimología , Enzimas/aislamiento & purificación , Enzimas/metabolismo , Inulina/biosíntesis , Sacarosa/metabolismo , Secuencia de Aminoácidos , Enzimas/química , Concentración de Iones de Hidrógeno , Cinética , Datos de Secuencia Molecular , Peso Molecular , Especificidad por Sustrato , Temperatura
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