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1.
Ultrasonics ; 113: 106343, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33540235

RESUMO

We experimentally investigate and characterize high order Lamb wave modes in a dry human skull. Specifically, we show that the diploë supports distinct wave modes in the sub-1.0 MHz frequency regime, and we employ these modes for the estimation of equivalent mechanical properties of cortical and trabecular bones. These modes are efficiently generated in a parietal region by direct contact excitation with a wedge beam transducer, and are recorded via infrared laser vibrometry. Frequency/wavenumber data are estimated using a matrix pencil method applied to wavefield measurements recorded on the outer cortical surface. The semi-analytical finite element model of an equivalent three-layered plate provides the platform for the identification of wave modes based on their through-the-thickness profiles, and supports the estimation of equivalent mechanical properties in conjunction with an optimization algorithm developed for this purpose. The results presented herein illustrate how high order Lamb waves can be used to gain understanding of the wave properties of a human skull and to estimate the orthotropic and equivalent isotropic mechanical properties of cortical and trabecular bones.


Assuntos
Crânio/fisiologia , Ultrassom/métodos , Fenômenos Biomecânicos , Análise de Elementos Finitos , Humanos , Técnicas In Vitro , Masculino
2.
Carbohydr Polym ; 251: 117006, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142573

RESUMO

Mushroom-derived polysaccharides (especially ß-glucans) are gaining much interest from researchers and industries recently due to their antioxidant, antitumor, immune-modulating activities, and other health benefits. Besides conventional extraction methods, a wide range of advanced extraction technologies is available nowadays for the recovery of these bioactive ingredients from mushrooms, such as ultrasonic-assisted extraction (UAE), microwave-assisted extraction (MAE), enzyme-assisted extraction (EAE), ultrasonic-microwave synergistic extraction (UMSE), subcritical water extraction (SWE), pulsed electric field-assisted extraction (PEFAE), aqueous two-phase extraction (ATPE), integrated extraction techniques, and other novel extraction technologies. This review describes the background of edible mushrooms, followed by the structural characteristics and biological activities of mushroom-derived polysaccharides. Then, the recent developments in the technologies used for the extraction of mushroom polysaccharides are discussed and summarized, together with their strengths and limitations as well as the underlying mechanisms. Finally, these advanced extraction techniques are compared and critically analyzed. Future outlook has also been proposed.


Assuntos
Agaricales/química , Polissacarídeos/isolamento & purificação , Micro-Ondas , Ultrassom/métodos
3.
J Sci Food Agric ; 101(1): 120-130, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32613628

RESUMO

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.


Assuntos
Mirtilos Azuis (Planta)/química , Carboidratos/química , Tecnologia de Alimentos/métodos , Extratos Vegetais/química , Ultrassom/métodos , Proteínas do Soro do Leite/química , Cápsulas/química , Frutas/química , Tamanho da Partícula , Pós/química , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/química , Temperatura , Ultrassom/instrumentação , Viscosidade , Difração de Raios X
4.
J Sci Food Agric ; 101(2): 648-658, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32691872

RESUMO

BACKGROUND: Clown featherback (Chitala ornata) skin, a by-product from the filleting process line, could serve as a good aquatic collagenous source. Nevertheless, the typical collagen extraction method is a time-consuming process providing a relatively low yield. Ultrasound had been reported to be an alternative technique for enhancing the extraction efficiency of several compounds, although the harsh conditions of ultrasound could affect their physicochemical and molecular characteristics. Thus, the application of ultrasonication under appropriate conditions could comprise a promising means for improving the extraction efficiency of collagen from clown featherback skin. RESULTS: Ultrasonication using different amplitudes (20-80%) and times (10-30 min) was implemented during extraction. An ultrasound-assisted process (UAP) was able to increase the yield of collagen (P ˂ 0.05) and could also result in a collagen purity decrease as evaluated by hydroxyproline content. There was no dramatic change in the solubility of resulting collagens. UAP induced protein degradation, particularly with an increasing amplitude and time, where slight changes in the isoelectric point value of collagen were observed. UAP had no adverse effect on molecular structure, where a triple-helical structure was still retained when an 80% amplitude was employed for 10 min (UAP-80/10-C). The amino acid composition of UAP-80/10-C reconfirmed the unique characteristic of collagen containing imino acid. CONCLUSION: An UAP under appropriate conditions could be used to improve the extraction yield with minimal effects on the molecular integrity of the resulting collagen. In addition, fish skin waste from the cutting process line, particularly clown featherback skin, could be exploited as a value-added product, comprising fish skin collagen. © 2020 Society of Chemical Industry.


Assuntos
Colágeno/isolamento & purificação , Proteínas de Peixes/isolamento & purificação , Ultrassom/métodos , Aminoácidos/química , Animais , Colágeno/química , Proteínas de Peixes/química , Peixes , Pele/química , Solubilidade , Resíduos/análise
5.
PLoS One ; 15(9): e0239593, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32970754

RESUMO

The method for increasing the separation efficiency of particles smaller than 2.5 micrometers by combined ultrasonic agglomeration and swirling flow technique is proposed in the article. The swirling flow creates areas with an increased concentration of particles on the outer radius of the vortex. The ultrasonic exposure on these areas leads to more efficient agglomeration and the formation of agglomerates of many times larger than the original particles. The resulting agglomerates are easily separated from the gas flow. The design of the agglomerator was developed. The vortex velocity is determined, at which ultrasonic exposure on the swirling flow increases the average particle size d32 = 2.5 micrometer to 4.5 times. The ultrasonic exposure on a rectilinear flow can increase the particle size no more than 1.6 times for comparison. The proposed method is compared with inertial gas clearing in a cyclone. It was found that the proposed combined method allows increasing the cleaning efficiency from 46% to 85% at ultrasonic exposure on the swirling flow in the agglomerator and cyclone.


Assuntos
Hidrodinâmica , Nanopartículas/química , Ultrassom/métodos , Aerossóis/metabolismo , Separação Celular/métodos , Tamanho da Partícula , Fenômenos Físicos
6.
Medicine (Baltimore) ; 99(34): e21937, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32846863

RESUMO

RATIONALE: Microspherophakia is characterized by a small, spherical crystalline lens with increased sagittal diameter. Because of the uncertainty about the outcome, as well as the complexity of the operation and development of complications, the management and timing of surgical intervention for microspherophakia are still debated. Lens extraction is effective for avoiding the risk of pupillary blockage, but the outcome after operation is controversial. The iTrace (Tracey, USA) report shows the influence of low-order aberrations (LOA) and high-order aberrations (HOA), which may be valuable in predicting postoperative outcome. Our report concerns a child with microspherophakia who underwent lens extraction via the analysis of visual quality by iTrace. PATIENT CONCERNS: Our report is on the case of a 7-year-old girl whose parents observed she had to bring her papers and books extremely close to her face to read. On examination, the girl was bilaterally diagnosed microspherophakia with a small tremble lens. The objective refraction was -15.0 diopter of spherical power (DS)/-1.00 diopter of cylindrical power (DC) × 180 right eye (OD) and -12.5 DS/-1.50 DC × 20 left eye (OS). The HOA of OD and OS were high up to 0.926 and 0.659, respectively by iTrace. The visual quality remained terrible after correcting LOA (high myopia and astigmatism). According to iTrace report, the patient would get a good visual quality by extracting the clear lens with HOA from cornea after correcting LOA. The girl's parent opted for surgery on the left eye. DIAGNOSIS: Due to the patient's symptoms, examination results, she was diagnosed with microspherophakia. INTERVENTIONS: The patient underwent clear lens extraction by ultrasonic phacoemulsification and intraocular lens implantation. OUTCOMES: The first day after operation, total HOA was decreased to 0.077. Total LOA was 0.713. Corrected distance visual acuity (CDVA) is 20/20. One week after surgery, HOA was 0.110 and LOA was 0.328. CDVA was 20/25. CDVA was still 20/25 one month after surgery. The total HOA was 0.110 and the LOA was 0.334 by iTrace. LESSONS: ITrace not only plays an important role in analyzing potential reasons of undesirable preoperative visual quality but also can predict postoperative outcomes. All these functions are helpful for determining surgical intervention of microspherophakia cases.


Assuntos
Aberrometria/instrumentação , Doenças da Córnea/cirurgia , Ectopia do Cristalino/cirurgia , Glaucoma/cirurgia , Iris/anormalidades , Implante de Lente Intraocular/métodos , Facoemulsificação/instrumentação , Ultrassom/métodos , Astigmatismo/cirurgia , Criança , Doenças da Córnea/diagnóstico , Topografia da Córnea/instrumentação , Ectopia do Cristalino/diagnóstico , Feminino , Glaucoma/diagnóstico , Humanos , Iris/cirurgia , Miopia/cirurgia , Resultado do Tratamento , Acuidade Visual
7.
Food Chem ; 333: 127455, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32653683

RESUMO

Ultrasound (US) has been recognized as a non-thermal technology for accelerating blueberry wine aging for flavor development. However, influence of US on anthocyanin and color characteristics is uncertain. In this study, US was applied to new blueberry wine, and changes in color characteristics, anthocyanin content and anti-oxidant capacity were evaluated at early stage of aging period. Low-frequency power US resulted in an improvement in color characteristics and lower chromatic aberration as compared to untreated samples, specially at condition of 180 W, 20 min and 2 cycles. Furthermore, this contribution was attributed to unattenuated anthocyanins protected from US stress. Importantly, the structural polarity dependence was mediated by the impact of US on anthocyanins. Additionally, anti-oxidant activity of blueberry wine was not adversely affected under a moderate US condition. US treatment of blueberry wine was therefore considered to significantly enhance the color presentation, hinting at the possibility of promoting blueberry wine aging.


Assuntos
Antocianinas/química , Antioxidantes/química , Mirtilos Azuis (Planta) , Ultrassom/métodos , Vinho , Antocianinas/análise , Antioxidantes/análise , Mirtilos Azuis (Planta)/química , Cor , Indústria de Processamento de Alimentos/métodos , Vinho/análise
8.
Food Chem ; 333: 127500, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32693317

RESUMO

The objectives of this study were to optimize the condition of ultrasonic treatment combined with aqueous chlorine dioxide (ClO2) on nitrate content of spinach by response surface methodology (RSM), and determine the effectiveness of ultrasound (US) and ClO2 alone and in combination, on spinach postharvest quality during 7 days' storage period. The optimal treatment parameters obtained were ultrasonic power (300 W), ClO2 concentration (50 ppm), treatment time (4 min). The combined treatments significantly reduced the nitrate content and maintained better storage quality in terms of total soluble solids (TSS) and ascorbic acid content compared with the individual treatment or untreated. For Chlorophyll content, the combined treatment was significantly higher than the control and ClO2 treatment, but lower than ultrasonic treatment. The results demonstrated that US combined with ClO2 are promising alternatives for the reduction of nitrate content, as well as preserving the quality of stored leafy vegetables.


Assuntos
Compostos Clorados/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Nitratos/análise , Óxidos/farmacologia , Spinacia oleracea/química , Ultrassom/métodos , Ácido Ascórbico/análise , Clorofila/análise , Conservação de Alimentos/instrumentação , Armazenamento de Alimentos , Folhas de Planta/química , Spinacia oleracea/efeitos dos fármacos , Verduras/química , Verduras/efeitos dos fármacos
9.
J Chromatogr A ; 1625: 461307, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32709350

RESUMO

In this study, the ultrasonic-assisted dispersive solid phase extraction (UA-d-SPE) method coupled to gas chromatography-mass spectrometry (GC-MS) was applied for the analysis of phthalate esters in drinking water and distilled herbal beverages (Rosa, Mentha, Cichorium). A new nanocomposite based on layered double hydroxide supported on graphene oxide was synthesized and modified by sulfonated polyaniline via a simple one-pot in-situ polymerization method. The structure and morphology of the nanocomposite was confirmed by means of complementary techniques: Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and transmission electron microscopy. The effects of key parameters including adsorbent mass, type and amount of back extraction solvent, extraction and desorption time, pH of the solution and ionic strength were optimized and good precision and sensitivity were achieved. Under the optimum conditions, the limits of detection were between 0.06-0.3 ng mL-1 in aqueous solutions. The hybrid nanomaterial exhibited good adsorption ability toward phthalates in drinking water and distilled herbal beverages. The relative standard deviations (RSD%) for beverage samples varied from 0.1% to 9.9% (n = 3). The relative recoveries varied from 54.5% to 112.6%.


Assuntos
Compostos de Anilina/química , Bebidas/análise , Grafite/química , Hidróxidos/química , Ácidos Ftálicos/isolamento & purificação , Extração em Fase Sólida/métodos , Ácidos Sulfônicos/química , Ultrassom/métodos , Adsorção , Ésteres/análise , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Nanocompostos/química , Concentração Osmolar , Ácidos Ftálicos/análise , Preparações de Plantas/química , Reprodutibilidade dos Testes , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo , Difração de Raios X
11.
J Food Sci ; 85(6): 1742-1751, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32449951

RESUMO

Coffee leaves contain various bioactive compounds that are beneficial for human health. However, there are very limited researches related to the extraction of the bioactive phytochemicals from coffee leaves. In the present study, the extraction conditions for bioactive components from coffee leaves were optimized using Taguchi design and response surface methodology (RSM). Taguchi design was used to screen significant factors that affected the yield of phytochemicals including trigonelline, caffeine, chlorogenic acids, mangiferin, and rutin, total phenolic content (TPC) and antioxidant activity. Sequentially, a Box-Behnken design (BBD) was used to optimize the extraction conditions. Three factors including Liquid-to-solid (L:S) ratio, ethanol concentration, and extraction temperature that significantly affected most of the phytochemical yields and antioxidant activity were selected from the six variables using Taguchi design. The optimal extraction conditions obtained from RSM were 30.3:1 L:S ratio, 54.5% ethanol, and 80 °C when simultaneously considered four responses, including TPC, the yields of mangiferin and 5-CQA and DPPH scavenging capacity. Under the optimal conditions, the experimental results for the above four responses were 62.1 mg gallic acid/g, 4.1 mg/g, 11.4 mg/g, and 356.9 µmol Trolox/g, respectively, which were close to the predicted values. About 97% of phytochemicals can be extracted in the first two times of extraction. In conclusion, the combination of Taguchi design and response surface methodology can be successfully used to screen and optimize the significant factors that affected the bioactive components extracted from coffee leaves. PRACTICAL APPLICATION: Coffee leaves, the byproducts of coffee plants, are considered no- or low-value although it has a long history for using them as tea-like beverage and ethnomedicine by locals in the coffee plant growing countries. Bioactive components extracted from coffee leaves can be used as ingredients in functional beverages, functional food, and natural health products. These applications will add values to coffee leaves as well as increase the incomes of coffee farmers and workers.


Assuntos
Fracionamento Químico/métodos , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Ultrassom/métodos , Humanos , Fenóis/análise , Fenóis/isolamento & purificação , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/química
12.
Food Chem ; 328: 127135, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32473490

RESUMO

Watermelon seed, a watermelon processing industry by-product, is a good protein source for the preparation of antioxidant peptides due to its high protein content, low cost, special amino acid composition. Antioxidant hydrolysates obtained from watermelon seed protein (WSP) after slit divergent ultrasound (SDU) treatment were studied. The stepwise multiple linear regression model verified that the reducing power of watermelon seed protein hydrolysates (WSPHs) is positively related with -SH and ß-turn content of WSP (R2 = 0.931, p < 0.01). Using the degree of hydrolysis (DH) and reducing power as indicators, the WSPHs was prepared under the optimal conditions (ultrasound frequency: 20/28 kHz, time: 60 min, power density: 100 W/L) and divided into three components by ultrafiltration membrane (1 and 5 kDa). Compared with WSPHs and other fractions, WSPHs-I (Mw < 1 kDa) not only significantly protected HepG2 cells from H2O2-induced damage, but also greatly alleviated the liver injury caused by d-galactose in male SD rats.


Assuntos
Antioxidantes/farmacologia , Citrullus/química , Hidrolisados de Proteína/química , Hidrolisados de Proteína/farmacologia , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Enzimas/metabolismo , Galactose/toxicidade , Células Hep G2 , Humanos , Peróxido de Hidrogênio/farmacologia , Hidrólise , Modelos Lineares , Masculino , Proteínas de Plantas/química , Proteínas de Plantas/farmacologia , Ratos Sprague-Dawley , Sementes/química , Ultrassom/instrumentação , Ultrassom/métodos
13.
Food Chem ; 322: 126645, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32335492

RESUMO

ß-Galactosidase formulations can be added to infant milks prior to feeding to reduce the level of lactose and to avoid symptoms of lactose intolerance. The hydrolysis of lactose affects osmolality, which is an important property of infant milk. This paper introduces novel ultrasonic technology for precision, real-time, non-destructive monitoring of osmolality of infant milks, including breast milk, during enzymatic hydrolysis of lactose by supplemental ß-galactosidases. This technology can be utilised in the development and testing of ß-galactosidase formulations. Additionally, ultrasonic real-time measurements of the average degree of polymerisation and molar mass of milk saccharides throughout the hydrolysis are discussed. Comparison of the ultrasonic results with discontinuous data of osmometry and HPLC showed an excellent agreement between the different techniques. The results elucidate the osmolality dynamics involved in the enzymatic hydrolysis of lactose in milks.


Assuntos
Fórmulas Infantis/química , Lactose/química , Leite Humano/química , Análise Espectral/métodos , Ultrassom/métodos , Animais , Bovinos , Feminino , Humanos , Hidrólise , Lactente , Peso Molecular , Oligossacarídeos/química , Concentração Osmolar , beta-Galactosidase/química
14.
J Food Sci ; 85(5): 1386-1396, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32333397

RESUMO

Ultrasound (US) is classified as a nonthermal treatment and it is used in food processing at a frequency range between 20 kHz and 1 MHz. Cavitation bubbles occur when the US strength is high enough to generate rarefaction that exceeds the intermolecular attraction forces in the medium. Currently, US is widely used in meat industries to enhance procedures, such as meat tenderization, emulsification mass transfer, marination, freezing, homogenization, crystallization, drying, and microorganism inactivation. In addition, combining ultrasonic energy with a sanitizing agent has a synergistic effect on microbial reduction. When poultry meat is treated using US, the expected quality is often better than the traditional methods, such as sanitization and freezing. US can be considered as a novel green technology for tenderizing and decontamination of poultry meat since both Escherichia coli and Salmonella are sensible to US. US improves the physical and chemical properties of meat proteins and can lead to a decrease in the α-helix in intramuscular protease complex in addition to a reduction in the viscosity coefficients. Therefore, ultrasonic treatment can be applied to enhance the textural properties of chicken meat. US can also be used to improve the drying rate when used under vacuum, compared with other traditional techniques. This review focuses on the potential of US applications in the management of poultry industries as the demand for good quality meat proteins is increasing worldwide.


Assuntos
Manipulação de Alimentos/métodos , Carne/análise , Ultrassom/métodos , Animais , Manipulação de Alimentos/instrumentação , Congelamento , Aves Domésticas , Salmonella/genética , Salmonella/isolamento & purificação , Ultrassom/instrumentação , Vácuo
15.
Int J Nanomedicine ; 15: 2027-2044, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32273700

RESUMO

Purpose: As one of the classic anti-Canidia albicans (CA) and vulvovaginal candidiasis (VVC) drugs, nystatin (NYS) is limited by poor water solubility and easy aggregation. Traditional NYS vaginal delivery formulations do not fully adapt to the specific environment of the vaginal cavity. The use of exopolysaccharides (EPS) has great application potential in emulsifiers, but its use has not been reported in nanoemulsions. In this work, an EPS/NYS nanoemulsion (ENNE) was developed to improve the activities of NYS against CA and VVC. Methods: The ENNE was prepared by ultrasonic method using EPS as an emulsifier, liquid paraffin oil as an oil phase, PEG400 as a co-emulsifier, and NYS as the loaded drug. ENNE preparation was optimized by response surface method. After optimization, in vitro and in vivo analysis of the anti-CA activity; animal experiments; staining with propidium iodide (PI), periodic acid-schiff (PAS), and hematoxylin-eosin (H&E); and cytokine experiments were performed to investigate the therapeutic ability against VVC. Results: The optimal formulation and preparation parameters of ENNE were determined as follows: EPS content of 1.5%, PEG400 content of 3.2%, NYS content of 700 µg/mL, paraffin oil content of 5.0%, ultrasonic time of 15 min, and ultrasonic amplitude of 35%. The ENNE showed an encapsulated structure with an average particle size of 131.1 ± 4.32 nm. ENNE exhibited high storage and pH stability, as well as slow release. The minimum inhibitory concentration (MIC) of ENNE against CA was only 0.125 µg/mL and the inhibition zone was 19.0 ± 0.5 mm, for greatly improved anti-CA effect. The prepared ENNE destroyed the membrane of CA cells, and exhibited good anti-CA effect in vivo and therapeutic ability against VVC. Conclusion: The results of this study will promote the application of EPS in nanotechnology, which should lead to new and effective local drug formulations for treating VVC.


Assuntos
Antifúngicos/administração & dosagem , Candidíase Vulvovaginal/tratamento farmacológico , Emulsões/química , Nanoestruturas/administração & dosagem , Nistatina/administração & dosagem , Administração Intravaginal , Animais , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Citocinas , Emulsificantes/química , Emulsões/administração & dosagem , Feminino , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana , Nanoestruturas/química , Nistatina/farmacologia , Tamanho da Partícula , Polietilenoglicóis/química , Polissacarídeos Bacterianos/química , Ultrassom/métodos
16.
Ultrasonics ; 104: 106110, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32146383

RESUMO

Surface mechanical attrition treatment (SMAT) of metallic biomaterials has gained significant importance due to its ability to develop nano structure in the surface region. In the present study, the microstructural changes and corrosion behavior of the commercially pure titanium (cp-Ti), following different durations of ultrasonic shot peening (USSP) has been investigated. cp-Ti was shot peened for different durations from 0 to 120 s and the treated samples were examined for microstructural changes in the surface region, cell viability and corrosion behavior. Cell viability was considerably increased after USSP for 60-120 s, exhibiting maximum for the 90 s of USSP. The passivation tendency was also improved with peening duration up to 90 s, however, it declined for longer duration of USSP. The beneficial effects of USSP may be attributed to nano structuring in the surface region and development of higher positive potentials at the USSP treated surface. Transmission Electron Microscope (TEM) examination of the USSPed surface revealed dislocation entanglement and substructure. Also, higher surface volta potential was observed over the USSPed sample exhibiting better cell proliferation. The present work is corollary to previous work of the group and mainly discusses the role of USSP duration, as a process parameter, on the cell viability and corrosion resistance of cp-Ti.


Assuntos
Células-Tronco Mesenquimais/fisiologia , Nanoestruturas/química , Titânio/química , Ultrassom/métodos , Proliferação de Células , Sobrevivência Celular , Corrosão , Técnicas Eletroquímicas , Humanos , Teste de Materiais , Microscopia de Força Atômica , Microscopia Eletrônica , Propriedades de Superfície , Difração de Raios X
17.
Rev. cuba. pediatr ; 92(1): e990, ene.-mar. 2020. graf
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1093749

RESUMO

Introducción: El síndrome prune belly es una rara y compleja anomalía congénita y el seudo prune belly es aún más raro y en muchas ocasiones no se diagnostica como tal. Objetivo: Describir un paciente con las características de este síndrome. Presentación del caso: Feto de sexo masculino que en la semana 23 del embarazo el ultrasonido prenatal detectó dilatación pélvica bilateral y se propuso la interrupción del embarazo que no fue aceptada por los padres. Al nacer se observa criptorquidia bilateral, el ultrasonido renal a las 34 horas de nacido confirma dilatación pélvica bilateral severa, se indica profilaxis con cefalexina, y a los cuatro dias de nacido es enviado a consulta de nefrología. Al llegar a consulta se observa la ausencia de testículos en ambas bolsas escrotales y el ultrasonido abdominal a los 16 dias confirma dilatación pélvica renal derecha severa y uréter dilatado en su tercio superior con 6 mm de diámetro y ureteropielocaliectasia severa del lado izquierdo; no se visualiza testículo derecho y el izquierdo en canal inguinal mide 7 × 10 mm. La gammagrafía estática demostró hipocaptación marcada del radiofármaco por el riñón izquierdo y disminución de la función renal relativa y en la uretrocistografía miccional se encontró dilatación vesical y reflujo vesicoureteral con ureterohidronefrosis bilateral. Conclusiones: El seudo síndrome prune belly presenta alteraciones complejas del tracto urinario que son las que establecen el pronóstico en estos casos(AU)


Introduction: Prune belly syndrome is a rare and complex congenital anomaly and the pseudo prune belly is even rarer and often not diagnosed as such. Objective: To describe a patient with the characteristics of this syndrome. Presentation of the case: Male fetus that in the 23rd week of pregnancy it was detected a bilateral pelvic dilatation in the prenatal ultrasound; and it was proposed the termination of pregnancy which was not accepted by the parents. At birth it is observed bilateral cryptorchidism; the renal ultrasound at 34 hours after birth confirmed bilateral severe pelvic dilation, it is indicated prophylaxis with cephalexin, and at four days after birth, the newborn is remitted to the Nephrology consultation. In the consultation it was noticed the absence of scrotal sacs in both testicles and the abdominal ultrasound at 16 days after birth confirmed severe right renal pelvic dilatation and dilated ureter in its upper third with 6 mm of diameter and severe uretero-pielocaliectasy in the left side; it is not visualized the right testicle and the left in the inguinal channel measured 7 × 10 mm. Static scintigraphy showed marked hypocaptation of the radiopharmaceutical by the left kidney and decreased relative renal function, and in the voiding cystourethrogram it was found bladder dilation and vesicoureteral reflux with bilateral ureterohydronephrosis. Conclusions: The pseudo prune belly syndrome presents complex abnormalities of the urinary tract that are those which establish the prognosis in these cases(AU)


Assuntos
Humanos , Masculino , Recém-Nascido , Síndrome do Abdome em Ameixa Seca/diagnóstico por imagem , Ultrassom/métodos , Feto/anormalidades
18.
PLoS One ; 15(2): e0228892, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32045453

RESUMO

Ultrasonic vocalizations (USV) of laboratory rodents may serve as age-dependent indicators of emotional arousal and anxiety. Fast-growing Arvicolinae rodent species might be advantageous wild-type animal models for behavioural and medical research related to USV ontogeny. For the yellow steppe lemming Eolagurus luteus, only audible calls of adults were previously described. This study provides categorization and spectrographic analyses of 1176 USV calls emitted by 120 individual yellow steppe lemmings at 12 age classes, from birth to breeding adults over 90 days (d) of age, 10 individuals per age class, up to 10 USV calls per individual. The USV calls emerged since 1st day of pup life and occurred at all 12 age classes and in both sexes. The unified 2-min isolation procedure on an unfamiliar territory was equally applicable for inducing USV calls at all age classes. Rapid physical growth (1 g body weight gain per day from birth to 40 d of age) and the early (9-12 d) eyes opening correlated with the early (9-12 d) emergence of mature vocal patterns of USV calls. The mature vocal patterns included a prominent shift in percentages of chevron and upward contours of fundamental frequency (f0) and the changes in the acoustic variables of USV calls. Call duration was the longest at 1-4 d, significantly shorter at 9-12 d and did not between 9-12-d and older age classes. The maximum fundamental frequency (f0max) decreased with increase of age class, from about 50 kHz in neonates to about 40 kHz in adults. These ontogenetic pathways of USV duration and f0max (towards shorter and lower-frequency USV calls) were reminiscent of those in laboratory mice Mus musculus.


Assuntos
Vocalização Animal/classificação , Vocalização Animal/fisiologia , Acústica , Animais , Arvicolinae/crescimento & desenvolvimento , Arvicolinae/metabolismo , Emoções/fisiologia , Feminino , Masculino , Comportamento Social , Espectrografia do Som/métodos , Ondas Ultrassônicas , Ultrassom/métodos
19.
Sensors (Basel) ; 20(3)2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32028735

RESUMO

To protect crops from diseases and increase yields, chemical agents are applied by boom sprayers. To achieve the optimal effect, the boom and the crop canopy should be kept at an appropriate distance. So, it is crucial to be able to distinguish the crop canopy from other plant leaves. Based on ultrasonic ranging, this paper adopts the fuzzy iterative self-organizing data analysis technique algorithm to identify the canopy location. According to the structural characteristics of the crop canopy, based on fuzzy clustering, the algorithm can dynamically adjust the number and center of clusters so as to get the optimal results. Therefore, the distances from the sensor to the canopy or the ground can be accurately acquired, and the influence of lower leaves on the measurement results can be alleviated. Potted corn plants from the 3-leaf stage to the 6-leaf stage were tested on an experiment bench. The results showed that the calculated distances from the sensor to the canopy using this method had good correlation with the manually measured distances. The maximum error of calculated values appeared at the 3-leaf stage. With the growth of plants, the error of calculated values decreased. The increased sensor moving speeds led to increased error due to the reduced data points. From the 3-leaf stage to the 5-leaf stage, the distances from the sensor to the ground can also be obtained at the same time. The method proposed in this paper provides a practical resolution to localize the canopy for adjusting the height of sprayer boom.


Assuntos
Produtos Agrícolas , Análise de Dados , Folhas de Planta/crescimento & desenvolvimento , Ultrassom/métodos , Algoritmos , Humanos , Folhas de Planta/anatomia & histologia
20.
PLoS One ; 15(2): e0228907, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32040540

RESUMO

Rodents' ultrasonic vocalizations (USVs) provide useful information for assessing their social behaviors. Despite previous efforts in classifying subcategories of time-frequency patterns of USV syllables to study their functional relevance, methods for detecting vocal elements from continuously recorded data have remained sub-optimal. Here, we propose a novel procedure for detecting USV segments in continuous sound data containing background noise recorded during the observation of social behavior. The proposed procedure utilizes a stable version of the sound spectrogram and additional signal processing for better separation of vocal signals by reducing the variation of the background noise. Our procedure also provides precise time tracking of spectral peaks within each syllable. We demonstrated that this procedure can be applied to a variety of USVs obtained from several rodent species. Performance tests showed this method had greater accuracy in detecting USV syllables than conventional detection methods.


Assuntos
Roedores/fisiologia , Espectrografia do Som/métodos , Ultrassom/métodos , Vocalização Animal/fisiologia , Acústica , Animais , Bases de Dados Factuais , Feminino , Gerbillinae/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Muridae/fisiologia , Ratos , Ratos Endogâmicos Lew , Processamento de Sinais Assistido por Computador , Razão Sinal-Ruído , Espectrografia do Som/estatística & dados numéricos , Ultrassom/estatística & dados numéricos
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