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1.
PLoS One ; 18(4): e0283734, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37040363

RESUMO

This paper proposes a static anti-windup compensator (AWC) design methodology for the locally Lipschitz nonlinear systems, containing time-varying interval delays in input and output of the system in the presence of actuator saturation. Static AWC design is proposed for the systems by considering a delay-range-dependent methodology to consider less conservative delay bounds. The approach has been developed by utilizing an improved Lyapunov-Krasovskii functional, locally Lipschitz nonlinearity property, delay-interval, delay derivative upper bound, local sector condition, L2 gain reduction from exogenous input to exogenous output, improved Wirtinger inequality, additive time-varying delays, and convex optimization algorithms to obtain convex conditions for AWC gain calculations. In contrast to the existing results, the present work considers both input and output delays for the AWC design (along with their combined additive effect) and deals with a more generic locally Lipschitz class of nonlinear systems. The effectiveness of the proposed methodology is demonstrated via simulations for a nonlinear DC servo motor system, possessing multiple time-delays, dynamic nonlinearity and actuator constraints.


Assuntos
Redes Neurais de Computação , Percepção do Tempo , Algoritmos
2.
PLoS One ; 10(3): e0118914, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25790103

RESUMO

A 3-D beam scanning antenna array design is proposed that gives a whole 3-D spherical coverage and also suitable for various radar and body-worn devices in the Body Area Networks applications. The Array Factor (AF) of the proposed antenna is derived and its various parameters like directivity, Half Power Beam Width (HPBW) and Side Lobe Level (SLL) are calculated by varying the size of the proposed antenna array. Simulations were carried out in MATLAB 2012b. The radiators are considered isotropic and hence mutual coupling effects are ignored. The proposed array shows a considerable improvement against the existing cylindrical and coaxial cylindrical arrays in terms of 3-D scanning, size, directivity, HPBW and SLL.


Assuntos
Imageamento Tridimensional/instrumentação , Tecnologia sem Fio/instrumentação , Simulação por Computador , Imageamento Tridimensional/métodos
3.
Pak J Pharm Sci ; 27(6): 1881-4, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25362612

RESUMO

The present study is about to prepare stable cream of water-in-oil emulsion containing extracts of Crocus sativus against its base (without extracts) taken as control, to determine its stability on different storage conditions and effects on skin moisture contents and transepidermal water loss. The formulation contains 3% Crocus sativus (Saffron) concentrated extracts, and the base containing no extract, were formulated. Different stability tests were done on samples, which placed at 8°C, 25°C, 40°C and 40°C with 75% relative humidity, for 4 week period. These formulations (Creams) were applied on the cheeks of human volunteers for 8week period. To evaluate any effect produced by these formulations different skin parameters were monitored every week. The significant results of this study explored the fact that water-in-oil emulsion topical cream of saffron formulated from Crocus sativus extract has absolute physical stability at different storage conditions. The increase in skin moisture contents and changes in transepidermal water loss were significant (p<0.05) with respect to base and formulation respectively. Topical cream of Crocus sativus showed significant moisturizing effects on human skin.


Assuntos
Crocus , Emolientes/farmacologia , Extratos Vegetais/farmacologia , Água Corporal/metabolismo , Emulsões , Humanos , Concentração de Íons de Hidrogênio , Pomadas , Pele/efeitos dos fármacos , Pele/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-24311867

RESUMO

Aiming at the exploration of herbal use by society, crude extracts of the seeds of some commonly used medicinal plants (Vitis vinifera, Tamarindus indica and Glycin max) were screened for their free radical scavenging properties using ascorbic acid as standard antioxidant. Free radical scavenging activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical. The overall antioxidant activity of grape seeds (Vitis vinifera) was the strongest, followed in descending order by soybean (Glycin max) and tamarind (Tamarindus indica). The seeds extract of Vitis vinifera, Glycin max and Tamarindus indica showed 85.61%, 83.45% and 79.26%, DPPH scavenging activity respectively.


Assuntos
Sequestradores de Radicais Livres/análise , Glycine max/química , Extratos Vegetais/análise , Sementes , Tamarindus/química , Vitis/química , Antioxidantes/análise , Antioxidantes/química , Compostos de Bifenilo , Sequestradores de Radicais Livres/química , Radicais Livres , Indicadores e Reagentes , Picratos , Extratos Vegetais/química
5.
Atherosclerosis ; 210(2): 422-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20060974

RESUMO

OBJECTIVE: The preferred amino acids in the proteolytic sites have been considered to be similar between caspase-1 and caspase-9, which do not support their differential functions in inflammatory pyroptosis and apoptosis. We attempted to solve this problem. METHODS: We analyzed the flanking 20 amino acid residues in the cleavage sites in 34 caspase-1 and 11 capase-9 experimentally identified substrates. RESULTS: This study has made the following findings: first, we verified that caspase-1 and caspase-9 shared 100% aspartic acid in the P1 position. However, the structures in the cleavage sites of most caspase-1 substrates are different from that of caspase-9 substrates in the following three aspects, (a) the amino acid residues with the statistically high frequencies; (b) the hydrophobic amino acid occurrence frequencies; and (c) the charged amino acid occurrence frequencies; second, the amino acid pairs P1-P1' are different; third, our identified cleavage site patterns are useful in the prediction for the 91.4% cleavage sites of 35 new caspase-1 substrates. CONCLUSION: Since most caspase-1 substrates are involved in vascular function, inflammation and atherogenesis, our novel structural patterns for the caspases' substrates are significant in developing new diagnostics and therapeutics.


Assuntos
Apoptose , Caspase 1/metabolismo , Aminoácidos/química , Sítios de Ligação , Caspase 9/metabolismo , Caspases/metabolismo , Morte Celular , Regulação Enzimológica da Expressão Gênica , Humanos , Inflamação , Modelos Biológicos , Ligação Proteica , Especificidade por Substrato
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