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1.
Arq. ciências saúde UNIPAR ; 26(3): 949-963, set-dez. 2022.
Artículo en Portugués | LILACS | ID: biblio-1399512

RESUMEN

Introdução: O intestino é um órgão vital, entretanto, seu mau funcionamento pode gerar alguns distúrbios como por exemplo, "A síndrome do intestino irritável". O quadro desses pacientes são dores na barriga, inchaço abdominal e alteração na frequência das evacuações e na consistência das fezes. A fisioterapia tem apresentado meios que favorecem analgesia. Objetivo: Verificar os efeitos da Estimulação Elétrica Nervosa Transcutânea (TENS) e do Ultrassom (US) nos sintomas da síndrome do intestino irritável. Método: Foi utilizado o TENS na região abdominal, durante 15 minutos. O Ultrassom foi usado durante 3 minutos em cada região abdominal, somando 12 minutos ao total. O tratamento foi realizado durante um mês, com 9 sessões. Utilizou-se a Escala Visual Analógica (EVA) e o questionário Inflammatory Bowel Disease Questionnaire (IBDQ). Resultados: Nos sintomas intestinais obteve-se progresso de 5 pontos no questionário IBDQ e nos sintomas emocionais houve uma evolução de 9 pontos, sendo este, estatisticamente significante. Na escala EVA a média de escore diminui de 5,6 para 3,6 ao final da intervenção. Conclusão: A intervenção fisioterapêutica surtiu efeitos positivos e contribuiu para a diminuição da dor e os outros sintomas como: inchaço abdominal e diminuição na quantidade de evacuações e essa evolução auxiliou na qualidade de vida do voluntário.


Introduction: The intestine is a vital organ, however, due to its malfunction, some disorders appear, for example, "The irritable bowel syndrome", patients with this syndrome experience pain in the belly, abdominal swelling, changes in the frequency of bowel movements and stool consistency. Physiotherapy uses means that help to cause analgesia. Objective: To verify the effects of TENS and Ultrasound on the symptoms of the individual with irritable bowel syndrome, contributing to the quality of life. Method: TENS was used in the abdominal region in Burst mode with a frequency of 150Hz with amplitude until it caused a slight contraction, for 15 minutes. Ultrasound was used in continuous mode with a frequency of 1MHZ, with a dose of 0.5w / cm2, for 3 minutes in each abdominal region, adding 12 minutes to the total. The treatment was carried out for one month, with 9 sessions. The EVA scale and the IBDQ questionnaire were used. Results: In the intestinal symptoms there was an improvement of 5 points in the IBDQ questionnaire and in the emotional aspect there was an improvement of 9 points and in the emotional aspect it was statistically significant, passing through the Wilcoxon test, P (est.) = 0.031 P (exact) ) = 0.031. On the EVA scale, the mean score before the intervention was 5.6 and at the end 3.6. Conclusion: The physical therapy intervention had positive effects, helping to reduce pain and other symptoms such as:abdominal swelling, decrease in the amount of bowel movements and this improvement helped the individual's emotional state, however a study on the subject is still necessary.


Introducción: El intestino es un órgano vital, sin embargo, su mal funcionamiento puede generar algunos trastornos como el "síndrome del intestino irritable". Los síntomas de estos pacientes son dolor de estómago, hinchazón abdominal y alteración de la frecuencia de las deposiciones y de la consistencia de las heces. La fisioterapia ha presentado medios que favorecen la analgesia. Objetivo: Verificar los efectos de la Estimulación Nerviosa Eléctrica Transcutánea (TENS) y el Ultrasonido (US) en los síntomas del síndrome del intestino irritable. Método: Se utilizó TENS en la región abdominal durante 15 minutos. Los ultrasonidos se utilizaron durante 3 minutos en cada región abdominal, sumando 12 minutos en total. El tratamiento se llevó a cabo durante un mes, con 9 sesiones. Se utilizaron la Escala Visual Analógica (EVA) y el Cuestionario de Enfermedad Inflamatoria Intestinal (IBDQ). Resultados: En los síntomas intestinales hubo una progresión de 5 puntos en el cuestionario IBDQ y en los síntomas emocionales hubo una evolución de 9 puntos, siendo esto, estadísticamente significativo. En la escala VAS, la puntuación media disminuyó de 5,6 a 3,6 al final de la intervención. Conclusión: La intervención fisioterapéutica tuvo efectos positivos y contribuyó a la reducción del dolor y de otros síntomas como: hinchazón abdominal y disminución de la cantidad de deposiciones y esta evolución ayudó a la calidad de vida del voluntario.


Asunto(s)
Humanos , Masculino , Adulto , Ultrasonido/instrumentación , Estimulación Eléctrica Transcutánea del Nervio/instrumentación , Síndrome del Colon Irritable/diagnóstico , Síndrome del Colon Irritable/terapia , Calidad de Vida/psicología , Modalidades de Fisioterapia/instrumentación , Abdomen , Heces , Analgesia/instrumentación
2.
Molecules ; 26(13)2021 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-34201870

RESUMEN

Flavonoids in Rosa sterilis were studied. The flavonoids in Rosa sterilis were extracted by ultrasonic method, and the extraction conditions were modeled and optimized by response the surface methodology and the artificial intelligence method. The results show that the ultrasonic method can effectively extract total flavonoids, and the extraction rate is close to the prediction value of ANN-GA algorithm, which proves the rationality of the model. The order of the effects of the parameters on the experiment was material liquid ratio > extraction power > extraction time > ethanol concentration. In addition, the scavenging effects of flavonoids on DPPH, O2-· and ·OH were also determined, and these indicated that flavonoids have strong antioxidant activities. The kinetics of the extraction process was studied by using the data of the extraction process, and it was found that the extraction process conformed to Fick's first law.


Asunto(s)
Inteligencia Artificial , Flavonoides/análisis , Flavonoides/aislamiento & purificación , Depuradores de Radicales Libres/química , Rosa/química , Ultrasonido/métodos , Algoritmos , Antioxidantes/farmacología , Compuestos de Bifenilo/química , Etanol/química , Flavonoides/química , Cinética , Redes Neurales de la Computación , Picratos/química , Extractos Vegetales/farmacología , Ondas Ultrasónicas , Ultrasonido/instrumentación
3.
J Sci Food Agric ; 101(10): 4361-4372, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-33426672

RESUMEN

BACKGROUND: Ultrasonic pretreatment is a novel physical method that can be used in the extraction process of okra pectin. Real-time online monitoring technologies were introduced in time and frequency domains when okra was pretreated. Preparation time of dried okra and yield of okra pectin were studied; and physicochemical properties of okra pectin were analyzed at the optimum ultrasonic parameter. RESULTS: Results showed that ultrasonic intensity of sweeping-frequency ultrasonic (SFU) pretreatment was stronger than that of fixed-frequency ultrasonic pretreatment (FFU). SFU pretreatment (60 ± 1 kHz) at 30 min had a strong ultrasonic voltage peak of 0.05387 V and signal power peak of -6.62 dBm. The preparation time of dried okra was 160 ± 14.14 min in the pretreated group, 44.83% lower than control without SFU pretreatment. The intercellular space was 56.03% higher than control. Water diffusion coefficient increased from 1.41 × 10-9 to 2.14 × 10-9  m2  s-1 . Monobasic quadratic equations were developed for the monitored ultrasonic intensity and pectin yield. Compared to control, extraction yield (16.70%), pectin content (0.564 mg mg-1 ), solubility (0.8187 g g-1 ) and gel strength (30.91 g) were improved in the pretreated group. Viscosity decreased, and values of G' and G″ crossing at 63 rad s-1 revealed the viscoelastic behavior and the beginning of viscous behavior with a sol state. CONCLUSION: Decrement of dried preparation time and increment of yield were achieved by ultrasonic pretreatment during the extraction process of okra pectin, and the relationship of ultrasonic intensity monitored by real-time online technologies and yield was given. © 2021 Society of Chemical Industry.


Asunto(s)
Abelmoschus/química , Pectinas/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Ultrasonido/métodos , Peso Molecular , Pectinas/análisis , Extractos Vegetales/análisis , Solubilidad , Ultrasonido/instrumentación , Viscosidad
4.
J Sci Food Agric ; 101(1): 120-130, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-32613628

RESUMEN

BACKGROUND: An ultrasonic spray nozzle was evaluated for the production of powders and microcapsules, using blueberry extract, modified starch (HI-CAP 100), and whey protein isolate (WPI). The effects of ultrasonic power and the concentration of coating materials on the characteristics of the resulting samples - such as viscosity, particle size, microencapsulation efficiency, color, glass transition temperature, Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), and morphology - were also studied. RESULTS: The apparent viscosity was primarily affected by the self-heating of the ultrasonic nozzle as the power increased. The largest mean particle size of samples was observed under conditions of 30% coating concentration at 10 W. Glass transition temperatures (Tg ) of the samples were affected by all atomization parameters significantly (P < 0.05) and the highest Tg values of all samples were determined when the coating concentration was maximum (30%) and power level was minimum (5 W). The FTIR and XRD results indicate that the power of the ultrasonic nozzle did not cause any change in WPI structure and led to only a small change in the structure of HI-CAP 100 at 10 W. The short atomization time preserved, to some extent, the properties of the coating materials and the blueberry extract. With regard to the morphological properties, it was observed that the samples obtained with WPI showed less shrinkage than HI-CAP 100. CONCLUSION: The results indicated that an ultrasonic nozzle could be used successfully to prepare the blueberry microcapsule with HI-CAP 100 and WPI as coating materials. This study may contribute to the development of ultrasonic nozzle applications using different coatings for the microencapsulation of high-quality functional materials. © 2020 Society of Chemical Industry.


Asunto(s)
Arándanos Azules (Planta)/química , Carbohidratos/química , Tecnología de Alimentos/métodos , Extractos Vegetales/química , Ultrasonido/métodos , Proteína de Suero de Leche/química , Cápsulas/química , Frutas/química , Tamaño de la Partícula , Polvos/química , Espectroscopía Infrarroja por Transformada de Fourier , Almidón/química , Temperatura , Ultrasonido/instrumentación , Viscosidad , Difracción de Rayos X
5.
Sci Rep ; 9(1): 16120, 2019 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-31695137

RESUMEN

Byproducts such as orange peel have potential uses because of their bioactive compounds, which are important for their potential to reduce the risk factors of diseases caused by aging. The lack of effective techniques and the high levels of pollution produced by the conventional extraction of bioactive compounds using organic solvents have highlighted the need to enhance the 'green chemistry' trend. This study evaluates the use of ultrasound to extract bioactive compounds from orange peel. The antioxidant capacity, phenolic content, ascorbic acid, total carotenoids, and HPLC profile of phenolic compounds from orange peel extracts were obtained by a physicochemical evaluation. The results demonstrate that the optimal conditions for the ultrasound-assisted extraction of bioactive orange peel compounds were a power of 400 W, a time of 30 min, and 50% ethanol in water. These conditions were used to obtain a total carotenoid concentration of 0.63 mg ß-carotene/100 g, vitamin C concentration of 53.78 mg AA/100 g, phenolic concentration of 105.96 mg GAE/100 g, and antioxidant capacity of ORAC = 27.08 mM TE and TEAC = 3.97 mM TE. The major phenolic compound identified in all orange peel extracts was hesperidin, with a maximum concentration of 113.03 ± 0.08 mg/100 g.


Asunto(s)
Fraccionamiento Químico/métodos , Citrus sinensis/química , Tecnología Química Verde/métodos , Extractos Vegetales/aislamiento & purificación , Antioxidantes/análisis , Antioxidantes/aislamiento & purificación , Carotenoides/análisis , Carotenoides/aislamiento & purificación , Fraccionamiento Químico/instrumentación , Frutas/química , Tecnología Química Verde/instrumentación , Fenoles/análisis , Fenoles/aislamiento & purificación , Extractos Vegetales/análisis , Ultrasonido/instrumentación , Ultrasonido/métodos
6.
IEEE Trans Biomed Eng ; 66(1): 217-224, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29993389

RESUMEN

Neuromodulation is a fundamental method for obtaining basic information about neuronal circuits for use in treatments for neurological and psychiatric disorders. Ultrasound stimulation has become a promising approach for noninvasively inducing neuromodulation in animals and humans. However, the previous investigations were subject to substantial limitations, due to most of them involving anesthetized and fixed small-animal models. Studies of awake and freely moving animals are needed, but the currently used ultrasound devices are too bulky to be applied to a freely moving animal. This study is the first time to design and fabricate a miniature and lightweight head-mounted ultrasound stimulator for inducing neuromodulation in freely moving mice. The main components of the stimulator include a miniature piezoelectric ceramic, a concave epoxy acoustic lens, and housing and connection components. The device was able to induce action potentials recorded in situ and evoke head-turning behaviors by stimulating the primary somatosensory cortex barrel field of the mouse. These findings indicate that the proposed method can be used to induce noninvasive neuromodulation in freely moving mice. This novel method could potentially lead to the application of ultrasonic neuromodulation in more-extensive neuroscience investigations.


Asunto(s)
Estimulación Física/instrumentación , Ultrasonido/instrumentación , Animales , Conducta Animal/efectos de la radiación , Diseño de Equipo , Masculino , Ratones , Ratones Endogámicos C57BL , Estimulación Eléctrica Transcutánea del Nervio
7.
Microb Pathog ; 123: 144-148, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29981853

RESUMEN

High intensity ultrasound is becoming important and more widely used in the food industry for microorganisms decontamination. This sterilization technique has been evaluated to improve food safety and to replace common processing with chemical additive compounds. The efficiency of a horn-type power ultrasound treatment (300 W and 600 W, 28 kHz, 10-30 min) on Listeria monocytogenes, Bacillus cereus, Escherichia coli, Salmonella typhimurium bacteria suspensions and phytoviruses was examined in this study. The results of this study showed that ultrasonic treatment can be used to eliminate vegetative cells of gram-positive and gram-negative bacteria from 1.59 to 3.4 log in bacterial suspensions and some phytoviruses in fruits.


Asunto(s)
Bacterias/efectos de la radiación , Irradiación de Alimentos/métodos , Microbiología de Alimentos , Conservación de Alimentos/métodos , Ultrasonido/métodos , Virus/efectos de la radiación , Bacillus cereus/crecimiento & desarrollo , Bacillus cereus/efectos de la radiación , Bacterias/crecimiento & desarrollo , Recuento de Colonia Microbiana , Escherichia coli/crecimiento & desarrollo , Escherichia coli/efectos de la radiación , Contaminación de Alimentos/prevención & control , Industria de Alimentos , Inocuidad de los Alimentos , Frutas/virología , Listeria monocytogenes/crecimiento & desarrollo , Listeria monocytogenes/efectos de la radiación , Viabilidad Microbiana/efectos de la radiación , Salmonella typhimurium/crecimiento & desarrollo , Salmonella typhimurium/efectos de la radiación , Ultrasonido/instrumentación , Virus/crecimiento & desarrollo
8.
Pesqui. vet. bras ; 37(5): 516-520, maio 2017. tab, graf
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-895439

RESUMEN

Esse estudo teve por objetivo avaliar o potencial de transmissibilidade ultrassônica de um gel fitoterápico de copaíba da espécie Copaifera duckei Dwyer na concentração de 10%. A pesquisa foi registrada junto ao Sistema Brasileiro de Biodiversidade. O gel fitoterápico de Copaifera duckei 10% foi manipulado de acordo diretrizes da Farmacopéia Brasileira e testado em um aparelho de Ultrassom (US) operado na faixa de 1 MHz. Como grupos controle foram selecionados a água destilada e o gel hidroalcoólico. A análise ocorreu de forma qualitativa e quantitativa através do modelo proposto na literatura. O US foi programado para modos de corrente pulsado/contínuo e testados nas intensidades (0,2/0,4/0,6/0,8/1,0W/cm2), em 1mim/cm2. Os dados receberam tratamento estatístico pelo software BioEstat 5.3 e foi admitido um nível de significância de ≥0,05. No modo contínuo e na intensidade de 0.2W/cm2 o gel foi considerado "Bom transmissor", na intensidade de 0.4 W/cm2 e 0.6W/cm2 um "Transmissor moderado" e nas intensidades de 0.8W/cm2 e 1.0W/cm2 um "Transmissor pobre". Concluiu-se que o gel de C. duckei 10% não atenuou as ondas de US em nenhum modo ou intensidade testado. E pode assim ser adicionado a esse para tratamentos sendo considerado transmissor bom ou moderado de acordo com a intensidade do US.(AU)


This study aimed to evaluate the potential of transmissibility of an herbal gel of Copaifera duckei Dwyer at a concentration of 10%. The research was registered with the Brazilian Biodiversity System. The gel of Copaifera duckei 10% was guidelined by the Brazilian Pharmacopoeia and tested on an Ultrasound device (US) operated in the range of 1 MHz. The control groups were selected distilled water and hydro alcoholic gel. The analysis was qualitatively and quantitatively using the model proposed in the literature. The US was scheduled to current modes pulsed/continuous and tested in the intensities (0.2/0.4/0.6/0.8/1.0W/cm2) in 1mim/cm2. The data received statistical treatment by BioEstat software 5.3 and was admitted to a significance level of ≥0.05. In continuous mode and intensity of 0.2W/cm2 gel was considered "good transmitter" at the intensity of 0.4W/cm2 and 0.6W/cm2 a "moderate Transmitter" and the intensity of 0.8W/cm2 and 1.0W/cm2 a "poor transmitter". It was concluded that the 10% gel C. duckei US did not attenuate US waves in any form or intensity tested; it can thus be used for this treatment being considered a good or moderate transmitter according to the intensity of US.(AU)


Asunto(s)
Ultrasonido/instrumentación , Fonoforesis , Geles/uso terapéutico , Fabaceae/química , Fitoterapia/veterinaria , Resinas de Plantas/análisis
9.
J Agric Food Chem ; 65(12): 2572-2579, 2017 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-28267913

RESUMEN

Chia (Salvia hispanica L.) seeds contain an important amount of edible oil rich in omega-3 fatty acids. Fast and alternative extraction techniques based on polar solvents, such as ethanol or water, have become relevant for oil extraction in recent years. However, chia seeds also contain a large amount of soluble fiber or mucilage, which makes difficult an oil extraction process with polar solvents. For that reason, the aim of this study was to develop a gentle extraction method for mucilage in order to extract chia oil with polar solvents using pressurized liquids and compare with organic solvent extraction. The proposed mucilage extraction method, using an ultrasonic probe and only water, was optimized at mild conditions (50 °C and sonication 3 min) to guarantee the omega-3 oil quality. Chia oil extraction was performed using pressurized liquid extraction (PLE) with different solvents and their mixtures at five different extraction temperatures (60, 90, 120, 150, and 200 °C). Optimal PLE conditions were achieved with ethyl acetate or hexane at 90 °C in only 10 min of static extraction time (chia oil yield up to 30.93%). In addition, chia oils extracted with nonpolar and polar solvents by PLE were analyzed by gas chromatography-mass spectrometry (GC-MS) to evaluate fatty acid composition at different extraction conditions. Chia oil contained ∼65% of α-linolenic acid regardless of mucilage extraction method, solvent, or temperature used. Furthermore, tocopherols and tocotrienols were also analyzed by HPLC in the extracted chia oils. The mucilage removal allowed the subsequent extraction of the chia oil with polar or nonpolar solvents by PLE producing chia oil with the same fatty acid and tocopherol composition as traditional extraction.


Asunto(s)
Fraccionamiento Químico/métodos , Ácidos Grasos Omega-3/química , Mucílago de Planta/aislamiento & purificación , Aceites de Plantas/química , Salvia/química , Semillas/química , Ultrasonido/métodos , Fraccionamiento Químico/instrumentación , Ácidos Grasos Omega-3/aislamiento & purificación , Mucílago de Planta/análisis , Aceites de Plantas/aislamiento & purificación , Ultrasonido/instrumentación
10.
Zhongguo Zhong Yao Za Zhi ; 41(4): 683-688, 2016 Feb.
Artículo en Chino | MEDLINE | ID: mdl-28871693

RESUMEN

This paper is to investigate the optimization conditions of ultrasonic technique for extraction process of Xiaoqinglong granules in medium scale. First of all, single factor experiment was used to determine the overall impact tendency and range of each factor; secondly, Box-Behnken method was used for optimization and detecting the content of paeoniflorin, ephedrine hydrochloride, glycyrrhizic acid of the liquid medicine. Their respective extraction rate was calculated and the comprehensive evaluation was carried out. The results were used as the evaluation basis for the efficacy of Xiaoqinglong granules ultrasonic extraction. The test results showed that the optimum extraction process of Xiaoqinglong granules by ultrasonic extraction was under the following conditions: ultrasonic power 600 W, liquid-solid ratio 10∶1, extraction for 31 min. Under this condition, the predicted value of extraction rate for Xiaoqinglong granules was 85.90%, and the test value was 85.87%. The mathematical model(P<0.01) established in this paper was significant, and can be used for the analysis and prediction of the ultrasonic extraction process of Xiaoqinglong granules.


Asunto(s)
Fraccionamiento Químico/métodos , Medicamentos Herbarios Chinos/aislamiento & purificación , Plantas Medicinales/química , Ultrasonido/métodos , Fraccionamiento Químico/instrumentación , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos/análisis , Glucósidos/análisis , Glucósidos/aislamiento & purificación , Ácido Glicirrínico/análisis , Ácido Glicirrínico/química , Ácido Glicirrínico/aislamiento & purificación , Modelos Teóricos , Monoterpenos/análisis , Monoterpenos/aislamiento & purificación , Temperatura , Ultrasonido/instrumentación
11.
Masui ; 64(6): 671-4, 2015 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-26437564

RESUMEN

We developed a simulator using "slime" composed of polyvinyl alcohol (PVA) and borax to evaluate this new ultrasound-guided nerve block training model. Seventeen subjects used the training model in the present study. They had no previous experience in performing ultrasound-guided nerve block. A plastic case measuring 25 x 18 x 12 cm was filled with 8 cm of slime. Three pieces of gauze were placed between the slime layers at 2 cm intervals. An in-plane approach was used to visualize the needle for the nerve block, and the amount of time required to stop the needle on the second gauze was measured 5 times for each subject. Significant differences were observed between the times for the first experiment and those for the third experiment to the fifth experiment In the fourth and fifth experiments, all subjects visualized the nerve block needle clearly above the target layer and were able to stop the needle at the target layer. The present simulation using our proposed ultrasound-guided nerve block training model was useful in terms of the amount of time required to perform the procedure and as well as in terms of its safety.


Asunto(s)
Anestesia Local/instrumentación , Anestesiología/educación , Ultrasonido/instrumentación , Anestesia Local/métodos
12.
J Agric Food Chem ; 63(34): 7532-8, 2015 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-26330254

RESUMEN

Anthocyanins are frequently discussed as marker compounds for fruit product authenticity. Proper analysis including sample preparation for the determination of anthocyanin concentrations is crucial for the comparability of authenticity data. The present study determined the influence of accelerated solvent extraction (ASE) and ultrasound-assisted extraction (UAE), using two different solvent compositions on the anthocyanin profile of bilberries (Vaccinium myrtillus L.), lowbush blueberries (Vaccinium angustifolium Ait.), and American cranberries (Vaccinium macrocarpon Ait.). Besides differences in total anthocyanin concentrations in the extracts, significant deviations (p ≤ 0.05) in the individual anthocyanin concentration were observed, resulting in differing anthocyanin proportions. Linear discriminant analysis comparing the differences caused by the extraction method to the natural differences within a set of 26 bilberry and lowbush blueberry samples of different origins was conducted. It revealed that profile variations induced by the extraction methods are in a similar scale to profile variations as a result of geographic and climatic differences.


Asunto(s)
Antocianinas/aislamiento & purificación , Fraccionamiento Químico/métodos , Extractos Vegetales/aislamiento & purificación , Ultrasonido/métodos , Vaccinium/química , Antocianinas/química , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Fraccionamiento Químico/instrumentación , Análisis Discriminante , Frutas/química , Frutas/clasificación , Extractos Vegetales/química , Ultrasonido/instrumentación , Vaccinium/clasificación
14.
Ultrasonics ; 57: 84-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25465964

RESUMEN

A thermophone is a thermoacoustic transducer, which generates sound via time-varying Joule heating of an electrically conductive layer, which leads to expansion and contraction of a small pocket of air near the surface of the film. In this work, a 10-µm-thick Ag-Pd conductive film was coupled with heat-insulating and heat-releasing layers to fabricate a three-layer thermophone for generating ultrasound. The heat-insulating layer was 47 µm thick, and was made of glass. The heat-releasing layer was 594 µm thick, and was made of 94% alumina. Because of the simple sound-generation mechanism, which does not require mechanical moving parts, the Ag-Pd conductive film on the glass substrate can produce ultrasound radiation with broadband frequency characteristics, where exiting commercial electrode materials were used. We also demonstrate that the measured directivity patterns are in good agreement with theoretical predictions, assuming a rectangular diaphragm with the same size as the metallic film.


Asunto(s)
Vidrio/química , Plomo/química , Plata/química , Transductores , Ultrasonido/instrumentación , Óxido de Aluminio/química , Diseño de Equipo , Modelos Teóricos , Sonido , Propiedades de Superficie , Vibración
15.
Cryo Letters ; 35(5): 371-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25397951

RESUMEN

BACKGROUND: Ultrasonic waves are shown to enhance the rate of freezing. OBJECTIVE: To elucidate the mechanism of immersion freezing of potatos with ultrasonic waves. MATERIALS AND METHODS: Ultrasound is applied to potato samples immersed in degassed coolant and untreated coolant. Sonic waves were intermittently applied at temperature below -1 degree C. The freezing rates were measured under different experimental conditions. RESULTS: The use of ultrasonic waves increased the freezing rates of potatoes immersed in both degassed coolant and untreated coolant. However, the freezing rate in the degassed coolant was less than that in the untreated coolant. CONCLUSION: Heat transfer on the interface between the potato sample and sonicated degassed coolant appears to be less than that within the sample in the absence of cavitation. The interface heat transfer between the potato sample and untreated coolant is likely improved due to ultrasonic cavitation.


Asunto(s)
Criopreservación/instrumentación , Congelación , Solanum tuberosum , Ultrasonido/instrumentación , Criopreservación/métodos , Cristalización , Diseño de Equipo , Gases/química , Calor , Solanum tuberosum/química , Ultrasonido/métodos , Agua/química
16.
J Acoust Soc Am ; 135(4): 1978-85, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25234996

RESUMEN

Ultrasonic coded transmitters (UCTs) are high-frequency acoustic tags that are often used to conduct survivorship studies of vulnerable fish species. Recent observations of differential mortality in tag control studies suggest that fish instrumented with UCTs may be selectively targeted by marine mammal predators, thereby skewing valuable survivorship data. In order to better understand the ability of pinnipeds to detect UCT outputs, behavioral high-frequency hearing thresholds were obtained from a trained harbor seal (Phoca vitulina) and a trained California sea lion (Zalophus californianus). Thresholds were measured for extended (500 ms) and brief (10 ms) 69 kHz narrowband stimuli, as well as for a stimulus recorded directly from a Vemco V16-3H UCT, which consisted of eight 10 ms, 69 kHz pure-tone pulses. Detection thresholds for the harbor seal were as expected based on existing audiometric data for this species, while the California sea lion was much more sensitive than predicted. Given measured detection thresholds of 113 dB re 1 µPa and 124 dB re 1 µPa, respectively, both species are likely able to detect acoustic outputs of the Vemco V16-3H under water from distances exceeding 200 m in typical natural conditions, suggesting that these species are capable of using UCTs to detect free-ranging fish.


Asunto(s)
Percepción Auditiva , Monitoreo del Ambiente/instrumentación , Peces/fisiología , Phoca/fisiología , Conducta Predatoria , Leones Marinos/fisiología , Transductores , Ultrasonido/instrumentación , Estimulación Acústica , Animales , Audiometría de Tonos Puros , Umbral Auditivo , Señales (Psicología) , Diseño de Equipo , Femenino , Masculino , Detección de Señal Psicológica , Espectrografía del Sonido
17.
BMC Oral Health ; 14: 114, 2014 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-25201549

RESUMEN

BACKGROUND: Efforts to improve the efficacy of smear layer removal by applying irrigant activation at the final irrigation or by elevating the temperature of the irrigant have been reported. However, the combination of such activation protocols with 60 °C 3% sodium hypochlorite (NaOCl) has seldom been mentioned. The aim of this study was to compare the efficacy in smear layer removal of four different irrigation techniques combined with 60 °C 3% NaOCl and 17% EDTA. METHODS: Fifty single-rooted teeth were randomly divided into five groups (n = 10) according to the irrigant agitation protocols used during chemomechanical preparation(Dentsply Maillefer, Ballaigues, Switzerland): a side-vented needle group, a ultrasonic irrigation (UI) group, a NaviTip FX group, an EndoActivator group, and a control group (no agitation). After each instrumentation, the root canals were irrigated with 1 mL of 3% NaOCl at 60 °C for 1 minute, and after the whole instrumentation, the root canals were rinsed with 1 mL of 17% EDTA for 1 minute. Both NaOCl and EDTA were activated with one of the five irrigation protocols. The efficacy of smear layer removal was scored at the apical, middle and coronal thirds. The Data were statistically analyzed using SAS version 9.2 for Windows (rank sum test for a randomised block design and ANOVA). RESULTS: No significant differences among the NaviTip FX group, EndoActivator group and control groups, and each of these groups showed a lower score than that of UI group (P < 0.05). Within each group, all three thirds were ranked in the following order: coronal > middle > apical (P < 0.05). In the coronal third, the NaviTip FX group was better than UI group. In the middle and apical third, the differences were not significant among any of the groups. CONCLUSIONS: Even without any activation, the combination of 60 °C 3% NaOCl and 17% EDTA could remove the smear layer effectively, similar to NaviTip FX or EndoActivator, and these three protocols were more effective than UI. However, regardless of different types of irrigation technique applied, complete removal of the smear layer was not achieved, particularly in the apical third.


Asunto(s)
Cavidad Pulpar/efectos de los fármacos , Ácido Edético/uso terapéutico , Irrigantes del Conducto Radicular/uso terapéutico , Preparación del Conducto Radicular/métodos , Capa de Barro Dentinario , Hipoclorito de Sodio/uso terapéutico , Irrigación Terapéutica/métodos , Cavidad Pulpar/ultraestructura , Dentina/efectos de los fármacos , Dentina/ultraestructura , Calor , Humanos , Microscopía Electrónica de Rastreo , Preparación del Conducto Radicular/instrumentación , Irrigación Terapéutica/instrumentación , Ápice del Diente/efectos de los fármacos , Ápice del Diente/ultraestructura , Resultado del Tratamiento , Ultrasonido/instrumentación
18.
J Agric Food Chem ; 62(15): 3371-6, 2014 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-24665894

RESUMEN

Cauliflower waste contains high amounts phenolic compounds, but conventional solvent extraction misses high amounts of nonextractable phenolics (NEP), which may contribute more to the valorization of these waste streams. In this study, the NEP content and composition of cauliflower waste were investigated. The ability of alkaline hydrolysis, sonication, and their combination to release NEP was assessed. Alkaline hydrolysis with sonication was found to extract the highest NEP content (7.3 ± 0.17 mg gallic acid equivalents (GAE)/g dry waste), which was higher than the extractable fraction. The highest yield was obtained after treatment of 2 M NaOH at 60 °C for 30 min of sonication. Quantification and identification were done using U(H)PLC-DAD and U(H)PLC-ESI-MS(E). Kaempferol and quercetin glucosides along with several phenolic acids were found. The results of the study show that there are higher amounts of valuable health-promoting compounds from cauliflower waste than what is currently described in the literature.


Asunto(s)
Brassica/química , Fraccionamiento Químico/métodos , Fenoles/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Ultrasonido/métodos , Residuos/análisis , Fraccionamiento Químico/instrumentación , Hidrólisis , Espectrometría de Masas , Estructura Molecular , Fenoles/química , Extractos Vegetales/química , Ultrasonido/instrumentación
19.
Ultrason Sonochem ; 21(4): 1585-91, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24418101

RESUMEN

This paper investigates the production of biodiesel from palm oil using a combined mechanical stirred and ultrasonic reactor (MS-US). The incorporation of mechanical stirring into the ultrasonic reactor explored the further improvement the transesterification of palm oil. Initial reaction rate values were 54.1, 142.9 and 164.2 mmol/L min for the mechanical-stirred (MS), ultrasonic (US) and MS-US reactors, respectively. Suitable methanol to oil molar ratio and the catalyst loading values were found to be 6 and 1 of oil, respectively. The effect of ultrasonic operating parameters; i.e. frequency, location, and number of transducer, has been investigated. Based on the conversion yield at the reactor outlet after 1 h, the number of transducers showed a relevant role in the reaction rate. Frequency and transducer location would appear to have no significant effect. The properties of the obtained biodiesel (density, viscosity, pour point, and flash point) satisfy the ASTM standard. The combined MS-US reactors improved the reaction rate affording the methyl esters in higher yield.


Asunto(s)
Biocombustibles , Aceites de Plantas/química , Ultrasonido/métodos , Catálisis , Ésteres , Metanol/química , Aceite de Palma , Fenómenos Físicos , Ultrasonido/instrumentación
20.
J Periodontol ; 85(4): 562-8, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23855840

RESUMEN

BACKGROUND: The aerosol generated by an ultrasonic scaler contains microorganisms that can penetrate into the body through the respiratory system of dental surgeons and patients. The aim of this pilot study is to evaluate and compare the efficacy of commercially available preprocedural mouthrinses containing 0.2% chlorhexidine gluconate, an herbal mouthwash, and water in reducing the levels of viable bacteria in aerosols. METHODS: This single-center, double-masked, placebo-controlled, randomized, three-group parallel design was conducted over a period of 45 days. Twenty-four patients with chronic periodontitis were divided randomly into three groups (A, B, and C) of eight patients each to receive 0.2% chlorhexidine gluconate, herbal mouthwash, and water, respectively, as a preprocedural rinse. The aerosol produced by the ultrasonic unit was collected at patient's chest area, doctor's chest area, and assistant's chest area on blood agar plates in all three groups. The blood agar plates were incubated at 37°C for 48 hours, and the total number of colony-forming units (CFUs) was counted and statistically analyzed. RESULTS: The results showed that CFUs in groups A and B were significantly reduced compared with group C, P <0.001 (analysis of variance). Also, CFUs in group A were significantly reduced compared with group B, P <0.05 (independent t-test). The numbers of CFUs were highest at the patient's chest area and lowest at the assistant's chest area. CONCLUSION: This study suggests that a routine preprocedural mouthrinse could eliminate the majority of bacterial aerosols generated by the use of an ultrasonic unit, and that 0.2% chlorhexidine gluconate is more effective than herbal mouthwash.


Asunto(s)
Microbiología del Aire , Contaminantes Ocupacionales del Aire , Contaminación del Aire Interior/prevención & control , Bacterias/efectos de los fármacos , Raspado Dental/métodos , Antisépticos Bucales/uso terapéutico , Ultrasonido/instrumentación , Adulto , Aerosoles , Antiinfecciosos Locales/uso terapéutico , Carga Bacteriana/efectos de los fármacos , Clorhexidina/análogos & derivados , Clorhexidina/uso terapéutico , Periodontitis Crónica/terapia , Método Doble Ciego , Femenino , Humanos , Masculino , Viabilidad Microbiana/efectos de los fármacos , Persona de Mediana Edad , Fitoterapia/métodos , Proyectos Piloto , Placebos , Extractos Vegetales/uso terapéutico , Resultado del Tratamiento
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