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1.
Ultrason Sonochem ; 101: 106672, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37925915

RESUMO

Ovalbumin (OVA), characterized by its high concentration in eggs, possesses remarkable foaming properties. Nevertheless, OVA is highly sensitive to thermal changes and acid-base conditions, substantially hampering its application potential for foaming purposes within the food industry. This experiment aimed to examine the effects of preheating and high-intensity ultrasound (HIU) treatment at different powers on OVA foaming properties and explore the underlying mechanisms. The results revealed that OVA exhibited the highest foaming capacity (31.5 %) and foaming stability (96.7 %) under the treatment condition of 200w + 60°C. Additionally, significant improvements were observed in the content of free sulfhydryl groups (37.27 µmg/g), solution viscosity (142.33 mPa·s), and surface hydrophobicity (37.27 µg BPB) under this condition. The absolute value of the zeta potential (-10.28 mV) was significantly increased in the 200w + 60°C treatment group. Moreover, the polymer dispersity index of OVA (0.6045) was significantly reduced, resulting in improved dispersion than the control group. The structural analysis revealed significant changes in the α-helix and ß-sheet content of OVA after treatment at 200w + 60 °C. The X-ray diffraction pattern exhibited sharper peaks, indicating a crystal structure, and the fluorescence peak displayed a slight blue shift along with increased hydrophobicity. Moreover, the preheating and HIU treatment induced a continuous uneven and irregular pore structure in OVA, which ultimately enhanced its foaming properties. In conclusion, the preheating and HIU treatment offers a novel approach to enhance the foaming properties of OVA.


Assuntos
Ovalbumina , Ovalbumina/química , Interações Hidrofóbicas e Hidrofílicas , Viscosidade
2.
Food Res Int ; 169: 112916, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37254350

RESUMO

This investigation aims to elucidate the roles of lipids on the volatilome evolution of postmortem lamb and its possible modulated mechanism behind. Firstly, the physicochemical properties were evaluated as coordinating role of flavor quality, and results suggested that chilled storage improved tenderness of muscle tissue and induced color variation of lamb. According to multivariate results, the pattern shifts of volatile profile of chilled lamb could be differentiated successfully. Besides, the potential differential aroma-active compounds were identified, including up-regulated heptanol, 1-octen-3-ol, 6-methyl-2-heptanone, 3-heptanone, 2-pentyl furan and octanol in early stage of storage (days 0-3) and down-regulated hexanal, pentanal, hexanol, octanol, 6-methy-2-heptanone, heptanol, 1-octen-3-ol and benzaldehyde in later stage of storage (days 3-7). Then, discriminant analysis recognized the differential lipid species corresponding to different stages of lamb flavor development, involving phospholipids, sphingolipids, glycerolipids and fatty acyls. Herein, the degradation of acyl carnitine and diglyceride may be an important pathway that contributed to volatilome evolution of postmortem lamb in the early stage of storage. These results demonstrated a potential relationship between headspace volatilome and lipidome evolutions, providing a comprehensive understanding for development of lipid-derived volatile compounds of chilled lamb and useful for lamb characteristic flavor quality evaluation and control in future.


Assuntos
Lipidômica , Carne Vermelha , Ovinos , Animais , Heptanol , Carne Vermelha/análise , Octanóis
3.
Sci Rep ; 12(1): 21339, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494500

RESUMO

Nonlinear phenomenon is presently attracting considerable attention in the field of microelectromechanical systems (MEMS). By adjusting a controllable tuning voltage, the nonlinearity of microdevices, especially on microactuators, can be precisely manipulated. To trap and separate small particles, generating a large and stable rotation force is critical in micromanipulations. Here, we report a simple and potential angular momentum cell comprising a piezoelectric MEMS-based nonlinear multi-mode resonator with integrated electrodes. A nonlinear rotating nodal line has been observed in specific frequency bands by applying a controllable low voltage of sub 5 V on a 4-port resonator made of lead zirconate titanate (PZT) thin films. The magnitude of the actuated voltage is Complementary-Metal-Oxide-Semiconductor (CMOS)-compatible and easy to integrate with the circuit. Furthermore, the real-time rotation motion of the MEMS-based nonlinear multi-mode resonator is also verified by a laser doppler vibrometer (LDV) at both chirp and single input frequencies, respectively. Therefore, this angular momentum cell shows great potential in the application of micromanipulation.

4.
Sensors (Basel) ; 22(21)2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36366039

RESUMO

Healthcare is an important medical topic in recent years. In this study, the novelty we propose is the intelligent healthcare system using an inequality-type optimization mathematical model with signal-to-noise ratio (SNR) and wavelet-domain low-frequency amplitude adjustment techniques to hide patients' confidential data in their electrocardiogram (ECG) signals. The extraction of the hidden patient information also utilizes the low-frequency amplitude adjustment. The detailed steps of establishing the system are as follows. To integrate confidential patient data into ECG signals, we first propose a nonlinear model to optimize the quality of ECG signals with the embedded patients' confidential data including patient name, patient birthdate, date of medical treatment, and medical history. Then, we apply Simulated Annealing (SA) to solve the nonlinear model such that the ECG signals with embedded patients' confidential data have good SNR, good root mean square error (RMSE), and high similarity. In other words, the distortion of the PQRST complexes and the ECG shape caused by the embedded patients' confidential data is very small, and thus the quality of the embedded ECG signals meets the requirements of physiological diagnostics. In the terminals, one can receive the ECG signals with the embedded patients' confidential data. In addition, the embedded patients' confidential data can be received and extracted without the original ECG signals. The experimental results confirm the efficiency that our method maintains a high quality of each ECG signal with the embedded patient confidential data. Moreover, the embedded confidential data shows a good robustness against common attacks.


Assuntos
Eletrocardiografia , Processamento de Sinais Assistido por Computador , Humanos , Eletrocardiografia/métodos , Razão Sinal-Ruído , Modelos Teóricos , Atenção à Saúde , Algoritmos
5.
Ultrason Sonochem ; 64: 105018, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32070902

RESUMO

An ultrasonic technique was applied to formulation of two-phase water-in-paraffin oil emulsions loading a high-molecular polysaccharide chitosan (CS) and stabilized by an oil-soluble surfactant (Span80) at different operational conditions. The influence of chitosan molecular properties, phase volume ratio (φw), Span80 volume fraction (φs) and ultrasonic processing parameters were systemically investigated on the basis of mean droplet diameter (MDD) and polydispersity index (PDI) of emulsions. It was observed that the molecular weight (Mw) of CS was an important influential factor to MDD due to the non-Newtonian properties of CS solution varying with Mw. The minimum MDD of 198.5 nm with PDI of 0.326 was obtained with ultrasonic amplitude of 32% for 15 min at an optimum φw of 35%, φs of 8%, probe position of 2.2 cm to the top of emulsion, while CS with Mw of 400 kDa and deacetylation degree of 84.6% was used. The rise of emulsion viscosity and the reduction of negative zeta potential at φw increasing from 5% to 35% were beneficial to obtain finer droplets and more uniform distribution of emulsions, and emulsion viscosity could be represented as a monotonically-decreasing power function of MDD at the same φw. FTIR analysis indicated that the molecular structure of paraffin oil was unaffected during ultrasonication. Moreover, the emulsions exhibited a good stability at 4 °C with a slight phase separation at 25 °C after 24 h of storage. By analyzing the evolution of MDD, PDI and sedimentation index (SI) with time, coalescence model showed better fitting results as comparison to Ostwald ripening model, which demonstrated that the coalescence or flocculation was the dominant destabilizing mechanism for such W/O emulsions encapsulating CS. This study may provide a valuable contribution for the application of a non-Newtonian macromolecule solution as dispersed phase to generate nano-size W/O emulsions via ultrasound, and widen knowledge and interest of such emulsions in the functional biomaterial field.


Assuntos
Quitosana/química , Óleos/química , Sonicação , Água/química , Cápsulas , Emulsões , Peso Molecular , Parafina/química , Viscosidade
6.
Korean J Physiol Pharmacol ; 23(3): 161-169, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31080347

RESUMO

Fumigaclavine C (FC), an active indole alkaloid, is obtained from endophytic Aspergillus terreus (strain No. FC118) by the root of Rhizophora stylosa (Rhizophoraceae). This study is designed to evaluate whether FC has anti-adipogenic effects in 3T3-L1 adipocytes and whether it ameliorates lipid accumulation in high-fat diet (HFD)-induced obese mice. FC notably increased the levels of glycerol in the culture supernatants and markedly reduced lipid accumulation in 3T3-L1 adipocytes. FC differentially inhibited the expressions of adipogenesis-related genes, including the peroxisome proliferator-activated receptor proteins, CCAAT/enhancer-binding proteins, and sterol regulatory element-binding proteins. FC markedly reduced the expressions of lipid synthesis-related genes, such as the fatty acid binding protein, lipoprotein lipase, and fatty acid synthase. Furthermore, FC significantly increased the expressions of lipolysis-related genes, such as the hormone-sensitive lipase, Aquaporin-7, and adipose triglyceride lipase. In HFD-induced obese mice, intraperitoneal injections of FC decreased both the body weight and visceral adipose tissue weight. FC administration significantly reduced lipid accumulation. Moreover, FC could dose-dependently and differentially regulate the expressions of lipid metabolism-related transcription factors. All these data indicated that FC exhibited anti-obesity effects through modulating adipogenesis and lipolysis.

7.
Int J Med Mushrooms ; 21(9): 865-874, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32450026

RESUMO

In this study, phenolic compounds that graded prepared from Pleurotus citrinopileatus using different solvents were obtained. The total content of phenolic and flavonoid, the phenolic profiles, the antioxidant activities, the tyrosinase, and α-glucosidase inhibitory activities of different extracts were determined. The results showed the phenolic and flavonoid content in different extracts ranging from 0.188 to 2.677 mg GAE/g DW and 0.137 to 0.445 mg QE/g DW, respectively. Six phenolic compounds were identified in different extracts by HPLC and the content range from 0.48 to 5778.59 µg/g DW. The water extracts showed strong scavenging activity of radicals and tyrosinase inhibitory activity, whereas acetone extracts showed obvious reducing power and high α-glucosidase inhibitory activity. These findings confirm that the P. citrinopileatus mushroom is a potential natural source of antioxidants for use in food and medicine industries along with their possible applications in ant-melanin and antidiabetic applications.


Assuntos
Inibidores de Glicosídeo Hidrolases/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Fenóis/análise , Pleurotus/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Flavonoides/análise , alfa-Glucosidases/metabolismo
8.
Comput Med Imaging Graph ; 32(7): 601-10, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18722751

RESUMO

Automation of liver positron emission tomography (PET) image segmentation is proposed in this paper. A new active contour model (ACM), called Poisson Gradient Vector Flow (PGVF), with genetic algorithm (GA) constructs a scheme to automatically find the contour of liver in the PET images. PET is widely used for the clinical purpose, but image quality of PET makes the image segmentation be a tough work. Three image data sets are tested for evaluating the new segmentation approach of liver PET images. One image data set is adapted from the study of one person with a normal liver. The other two image data sets are adapted from the studies of two patients with abnormal livers. The results show that the regions of interest (ROI) of liver are automatically segmented from the images of three data sets.


Assuntos
Algoritmos , Inteligência Artificial , Interpretação de Imagem Assistida por Computador/métodos , Fígado/diagnóstico por imagem , Reconhecimento Automatizado de Padrão/métodos , Humanos , Aumento da Imagem/métodos , Cintilografia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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