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The issue of unified dissipativity-based Arcak-type state estimator design for delayed static neural networks (SNNs) with leakage term and noise distraction was considered here. An Arcak-type state observer, which is compact than the usually used Luenberger-type state estimator, is selected to implement the subject of a unified dissipativity performance of SNNs. This paper primarily concentrates on the issue of Arcak-type state estimator of delayed SNNs involving leakage delay. The first attempt is made to tackle the Arcak-type state estimator of SNNs with time delay in leakage term in this paper based on the unified criteria, by constructing a novel Lyapunov functional together with newly improved integral inequalities. As a result, a novel unified state estimation criterion is launched in the form of linear matrix inequalities (LMIs) and put forward to justify the dynamics of error system is extended dissipative with the influence of leakage term and estimator gain matrices K¯1 and K¯2. Finally, an interesting simulation study is ultimately explored to show the performance of the established unified dissipativity-based theoretical results, in which, comparison results are also made together with recent works as a special case.
Assuntos
Redes Neurais de Computação , Algoritmos , Simulação por Computador , Fatores de TempoRESUMO
This paper investigates the problems of exponential stability and dissipativity of generalized neural networks (GNNs) with time-varying delay signals. By constructing a novel Lyapunov-Krasovskii functionals (LKFs) with triple integral terms that contain more advantages of the state vectors of the neural networks, and the upper bound on the time-varying delay signals are formulated. We employ a new integral inequality technique (IIT), free-matrix-based (FMB) integral inequality approach, and Wirtinger double integral inequality (WDII) technique together with the reciprocally convex combination (RCC) approach to bound the time derivative of the LKFs. An improved exponential stability and strictly (Q,S,R)-γ-dissipative conditions of the addressed systems are represented by the linear matrix inequalities (LMIs). Finally, four interesting numerical examples are developed to verify the usefulness of the proposed method with a practical application to a biological network.
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Modelos Teóricos , Redes Neurais de Computação , Algoritmos , Fatores de TempoRESUMO
This paper deals with the problem of delay-interval-dependent stability criteria for switched Hopfield neural networks of neutral type with successive time-varying delay components. A novel Lyapunov-Krasovskii (L-K) functionals with triple integral terms which involves more information on the state vectors of the neural networks and upper bound of the successive time-varying delays is constructed. By using the famous Jensen's inequality, Wirtinger double integral inequality, introducing of some zero equations and using the reciprocal convex combination technique and Finsler's lemma, a novel delay-interval dependent stability criterion is derived in terms of linear matrix inequalities, which can be efficiently solved via standard numerical software. Moreover, it is also assumed that the lower bound of the successive leakage and discrete time-varying delays is not restricted to be zero. In addition, the obtained condition shows potential advantages over the existing ones since no useful term is ignored throughout the estimate of upper bound of the derivative of L-K functional. Using several examples, it is shown that the proposed stabilization theorem is asymptotically stable. Finally, illustrative examples are presented to demonstrate the effectiveness and usefulness of the proposed approach with a four-tank benchmark real-world problem.
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For the first time an easy-to-make receptor 2-chloro-3-(thiazol-2-ylamino)naphthalene-1,4-dione (R1) for highly selective sensing of Hg(ii) ions in aqueous solution and in the solid state through the formation of an Hg-C bond was developed. The Hg(ii) ion sensing properties of R1 were investigated using UV-Vis, fluorescence and (1)H & (13)C NMR spectral studies. The results indicated that the receptor selectively senses Hg(ii) ions via the formation of a 1 : 1 complex of moderate stability (Ka = 3.5 × 10(4) M(-1)). The NMR spectral studies indicated that complexation between R1 and Hg(ii) occurs through the formation of an Hg-C bond (after deprotonation), which was confirmed by a single crystal XRD analysis of the product. When Hg(ii) was added to a solution of R1 in DMF-water (1 : 9 v/v), a dramatic color change from pale brown to blue was observed, while many common cations and anions did not interfere with the recognition process. The detection limit was 0.3 µM, which is much lower than the permissible limit of Hg(ii) in drinking water (0.001 mg L(-1)) as recommended by the WHO. The simple grinding of R1 with Hg(ii) in the solid state also exhibited the same dramatic colour change which is easily detectable visually.
Assuntos
Mercúrio/análise , Mercúrio/química , Técnicas de Síntese em Fase Sólida/métodos , Água/análise , Água/química , Colorimetria/métodos , Espectroscopia de Ressonância Magnética/métodos , Soluções/análise , Soluções/químicaRESUMO
The design, synthesis, characterization and their anion sensing properties of two receptors capable of exhibiting azo-hydrazone tautomerism are reported. The anion sensing properties have been investigated using electronic, fluorescence and nuclear magnetic spectral studies in addition to electrochemical and visual detection experiments. Both the receptors selectively bind fluoride ion with >100 nm red-shift in the electronic spectrum and the color changes from yellow to red. The results of the spectral studies revealed that the sensing mechanism involves fluoride ion induced change of chromophore from C=N (hydrazone form) to N=N (azo form) in these receptors leading to the visible color change. Density Functional Theory calculations were conducted to rationalize the optical response of the receptors.
Assuntos
Compostos Azo/química , Fluoretos/química , Hidrazonas/química , Modelos Químicos , Espectrofotometria/métodosRESUMO
The present study demonstrates the anti-tumor effects of combined supplementations of dietary fish oil (Maxepa) and 1alpha,25-dihydroxyvitamin D(3) (vitamin D(3)) on 7,12-dimethylbenz(alpha)anthracene (DMBA)-induced rat mammary carcinogenesis. Female Sprague-Dawley rats at 50 days of age were treated with 7,12-dimethylbenz(alpha)anthracene (DMBA; 0.5mg/100g body weight) by a single tail vein injection in an oil emulsion. Both fish oil (rich in EPA and DHA) and vitamin D(3) were administered orally at a dose of 0.5 ml/day/rat and 0.3 microg/100 microL propylene glycol twice a week respectively and continued to 35 weeks after DMBA administration. Fish oil in combination with vitamin D(3) resulted in a significant reduction in incidence, multiplicity and volume of mammary tumors. These supplementation also inhibited DMBA-induced mammary 7-methylguanine DNA adducts formation, which was measured by HPLC-fluorescence assay (at four sequential time points; ANOVA, F=42.56, P<0.0001). Immunohistochemical analysis revealed that the effect of fish oil and vitamin D(3) occurred through suppression of cell proliferation (BrdU-LI: P<0.0001). Fish oil and vitamin D(3) together also reduced the mRNA expression of iNOS (84%, P<0.05). In view of their natural availability, non-toxicity and acceptability; combined supplementation of fish oil and vitamin D(3) might be effective for chemoprevention of mammary carcinogenesis.
Assuntos
9,10-Dimetil-1,2-benzantraceno/toxicidade , Calcitriol/farmacologia , Carcinógenos/toxicidade , Óleos de Peixe/farmacologia , Neoplasias Mamárias Experimentais/prevenção & controle , Animais , Sequência de Bases , Bromodesoxiuridina/metabolismo , Proliferação de Células , Primers do DNA , Feminino , Neoplasias Mamárias Experimentais/enzimologia , Neoplasias Mamárias Experimentais/patologia , Óxido Nítrico Sintase Tipo II/genética , RNA Mensageiro/genética , Ratos , Ratos Sprague-DawleyRESUMO
An attempt has been made to understand the hydrogeochemical parameters to develop water quality index in Thirumanimuttar sub-basin. A total of 148 groundwater samples were collected and analyzed for major cations and anions. The domination of cations and anions was in the order of Na>Mg>Ca>K for cations and Cl>HCO(3) >SO(4) in anions. The hydrogeochemical facies indicate alkalis (Na and K) exceed alkaline earths (Ca and Mg) and strong acids (Cl and SO(4)) exceed weak acid (HCO(3)). Water quality index rating was calculated to quantify overall water quality for human consumption. The PRM samples exhibit poor quality in greater percentage when compared with POM due to effective leaching of ions, over exploitation of groundwater, direct discharge of effluents and agricultural impact. The overlay of WQI with chloride and EC correspond to the same locations indicating the poor quality of groundwater in the study area. SAR, Na%, and TH were noted higher during both the seasons indicating most of the groundwater locations not suitable for irrigation purposes.
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Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Água Doce/química , Humanos , ÍndiaRESUMO
Chitosan adsorbed microspheres containing tetanus toxoid were prepared in the size range of 10 mum to 75 mum, by emulsion-cross linking technique at different speeds of agitation. The amount of tetanus toxoid incorporated into chitosan microspheres were estimated by limes flocculation test and in vivo evaluation of tetanus toxoid adsorbed chitosan microspheres were determined by toxin neutralization method using albino mice. The results of in vivo release for the batches of 10 mum and 25 mum correlates with the results of in vitro in which both the batches passes the limit of IP standard (4 Lf) where as, for the batches of 50 mum and 75 mum, the in vitro release of tetanus toxoid was 2 Lf. But our in vivo studies for the batches of 50 mum and 75 mum fail to pass the limit stated in IP. The release of tetanus toxoid from the chitosan microspheres was found to be sustained for the period of 6 months.
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The essential oil of leaves of various cupressus species Viz., C.glauca, C.funebris, C.lawsonia, C. macrocarpa & C. sempervirens have been studied for their antimicrobial activity against certain gram positive [B. substilis, S.aureus], gram negative [E.coli, P.aeruginesa] and fungi (A.niger, A.flavus, C.albicans & A. fumigatus) using two fold serial dilution technique. Our results revealed that, all the species possess significant antibacterial & antifungal activities.
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Leaves of Dodonaea viscose Linn are used in the treatment of gout and rheumatism. This present work deals with pharmacognostical studies such as leaf constants, ash values, extractive values and also preliminary phytochemical studies of leaves of Dodonaea Viscosa Linn.