133 research outputs found

    Comparison between two state estimation techniqueds for linear systems

    Get PDF
    20th World Congress of the International Federation of Automatic Control, Jul 2017, Toulouse, FranceThis paper presents a comparison in terms of accuracy and complexity between two approaches used for state estimation of linear systems: a classic Kalman filter and a guaranteed set-membership state estimation technique. The main goal of this paper is to analyze the advantages of these techniques and to combine them in the future in a new accurate and simple extension that handles system uncertainties and chance constraints. Two academic examples illustrate the main differences between the compared techniques

    A new approach for Guaranteed ellipsoidal state estimation

    Get PDF
    The 19th World Congress of the International Federation of Automatic Control 2014. Cape Town, SudáfricaThis paper proposes a new ellipsoid-based guaranteed state estimation approach for linear discrete-time systems with bounded perturbations and bounded measurement noise. This approach is based on the minimization of the radius of the ellipsoidal state estimation set. Firstly, the ellipsoidal state estimation is computed by off-line solving a Linear Matrix Inequality optimization problem. Secondly, a new online method is developed in order to improve the accuracy of the estimation but it leads to an increase of the online computation load. A new scaling technique is proposed to reduce the computation time, while keeping a good accuracy of the state estimation. An illustrative example is analyzed in order to show the advantages of the proposed approach

    Étude comparative de l’activité antispasmodique de l’extrait aqueux d’Ajuga iva L. et de l’ibuprofène chez les souris

    Get PDF
    Ajuga iva (L.) Schreber, utilisé dans la pharmacopée traditionnelle, pour des troubles gastro-intestinaux, le diabète et comme  hypocholestérolémiante. L’étude pharmacologique de l’extrait aqueux d’Ajuga iva (Lamiaceae) a été effectuée à l’aide de modèles animaux. L’évaluation de l’activité analgésique, montre que l’extrait aqueux à 0,4g/ L de cette plante induit une diminution du nombre de crampes abdominales dans le test de writhing provoqué par l’acide acétique à 1% Ajuga iva a un effet analgésique plus efficace que celui de l’ibuprofène, en effet ce dernier provoque une inhibition de la douleur de 77,53±3,80 % et celui de ,l’extrait aqueux d’Ajuga iva de 85,39±4,29 % pour la même concentration (200mg/kg). L’extrait aqueux d’Ajuga iva a des propriétés analgésiques qui justifient son usage traditionnel. Les effets  thérapeutiques sont induits par divers composés révélés lors du tri phyto chimique de cette plante (alcaloïdes, flavonoïdes, polyphénols, saponosides, et tanins catéchiques) qui constituent la base scientifique de l’utilisation thérapeutique traditionnelle de la plante étudiée.Mots- clés : Ajuga iva L., extrait aqueux, effet analgésique, ibuprofène, writhing test

    Activité hypoglycémique de l’extrait aqueux d’Ajuga iva L. schreber chez les rats diabétiques induite par l’alloxane

    Get PDF
    Ajuga iva (L) schreber est utilisé en médecine traditionnelle dans le traitement du diabète. Le but de cette étude était d'évaluer l'activité l'hypoglycémique de l'extrait aqueux de la partie aérienne de cette plante sur un modèle animal. L’extrait a été préparé dans de l'eau bouillante et le filtrat aqueux a été lyophilisé et conservé. A iva est une plante capable d’induire une hypoglycémie chez les rats diabétiques. Alloxane a été administré en dose unique (150 mg poids corporel / kg) par injection intra-péritonéal. Des rats femelles Wistar (n = 30) pesant 200 ± 2g divisés en 5 groupes, ont reçu des doses différentes (0,05 g/mL, 0,10 g/mL, 0,15 g/mL) par voie orale. Cette opération est répétée tous les jours pendant 3 semaines. La glycémie a été déterminée par la méthode enzymatique colorimétrique par spectrophotométrie. Seul l’extrait aqueux à forte dose a diminuée le taux du glucose sanguins de 62, 96±7, 30% comparativement au groupe control. Dans la présente étude, le potentiel hypoglycémiant de A iva est démontré chez le rat. Ces résultats confirment l'utilisation de cette plante comme antidiabétique.Mots-clés : Ajuga iva, extrait aqueux, alloxane, activité hypoglycémique, diabète.Hypoglycemic Activity of the aqueous extract of Ajuga iva L. in diabetic rats induced by alloxanAjuga iva (L) schreber is used in traditional medicine in the treatment of diabetes, The purpose of this study was to evaluate hypoglycemic effect of the aqueous extract of aerial parts of this plant on animal model. The extract was prepared in boiling water and the aqueous filtrate was lyophilized and conserved. A iva is a plant capable of inducing hypoglycemia in diabetic rats. Alloxan was administered as a single dose (150 mg body weight / kg) injection intaperitoneal injection. Female Wistar rats (n = 30) weighing 200 ± 2g divided into 5 groups received different doses (0.05 GML-1, 0.10 GML-1, 0.15 g / mL) by oral route. This is repeated every day for three weeks. Blood glucose was determined by the enzymatic and colorimetric method by spectrophotometry. Only the aqueous extract high dose rate decreased blood glucose of 62, 96 ± 7, 30% compared with the control group. In the present study, the hypoglycemic potential of the A iva was demonstrated in rats. These results give support to the traditional use of this plant as antidiabetic herbal medicine.Keywords : Ajuga iva L, aqueous extract, alloxan, diabetes, hypoglycemic activity

    Parámetros químicos y actividad antioxidante de aceitunas de mesa al estilo natural de color cambiante de la variedad Sigoise

    Get PDF
    A chemical characterization of turning color table olives of the Sigoise variety was made through their processing as natural-style. Polyphenols, sugars, tocopherols, fatty acids, and antioxidant activity in the olives were monitored throughout the elaboration process. Oleuropein, salidroside, hydroxytyrosol 4-glucoside, rutin, ligustroside and verbascoside showed a decrease of 16.90-83.34%, while hydroxytyrosol increased during the first months of brining. Glucose was consumed by 90% due to the metabolism of the fermentative microbiota. The tocopherol content remained stable during the process and only the α-tocopherol decreased. The fatty acids were not affected. The loss in antioxidant compounds resulted in a decrease in the percentage of DPPH radical inhibition from 75.91% in the raw fruit to 44.20% after 150 days of brining. Therefore, the turning color natural table olives of the Sigoise variety are a good source of bioactive compounds.La caracterización química de las aceitunas en salmuera de color cambiante de la variedad Sigoise se ha estudiado durante el proceso de elaboración, en particular la concentración de fenoles, azúcares, tocoferoles, ácidos grasos y la actividad antioxidante. La concentración de oleuropeína, salidrósido, hidroxitirosol 4-glucósido, rutina, ligustrósido y verbascósido disminuyó un 16,90-83,34% durante el primer mes en salmuera. El 90% de la glucosa fue consumida debido al metabolismo de la microbiota fermentativa. El contenido en tocoferoles se mantuvo constante durante el proceso y solo disminuyó el α-tocoferol. Los ácidos grasos no se vieron afectados. La pérdida de actividad antioxidante se tradujo en una disminución del porcentaje de inhibición del radical DPPH de un 75,91% del fruto fresco a 44,20% después de 150 días en salmuera. A pesar de todo, la aceituna color cambiante de la variedad Sigoise en salmuera es una buena fuente de compuestos bioactivos

    Étude phytochimique et évaluation de l’activité anti-oxydante de Thymus CIliatus ssp. Coloratus

    Get PDF
    Thymus ciliatus ssp. Coloratus, plante aromatique, spontanée et répandue en régions méditerranéennes et dans le nord de l’Algérie est très utilisée par les populations locales pour ses vertus médicinales. Les tests phytochimiques appliqués au Thymus ciliatus ssp coloratus ont montré la présence de quelques familles de composés chimiques et notamment les flavonoïdes. L'activité antioxydante in vitro de l’extrait de flavonoïdes a été évaluée par la technique de réduction du fer « FRAP » (ferric reducing antioxydant power) et par le test de DPPH. La première méthode a montré que la fraction acétate d’éthyle de la partie aérienne a une capacité à réduire le fer plus marquée que celles de l’acide ascorbique et le BHA et que celle des racines, est nettement inférieure. Quant aux fractions butanoliques des flavonoïdes de la partie aérienne et des racines, elles ont une capacité à réduire le fer largement inférieure à celles de l’acide ascorbique et le BHA. L’activité antioxydante, obtenue par la second procédé et relative à la fraction acétate d’éthyle des flavonoïdes de la partie aérienne de la plante est plus importante (I.C₅₀=0,85 mg/mL) que celles obtenues à partir d’antioxydants utilisés dans les industries alimentaire et pharmaceutique en l’occurrence l’acide ascorbique (I.C₅₀ = 1,12 mg/mL) et le BHA (I.C₅₀=1,61 mg/mL).Mots-clés : Thymus coloratus, activité antioxydant, flavonoïde, FRAP, DPPH.Phytochemical study and evaluation of the antioxidant activity of thymus ciliatus ssp. Coloratus Thymus ciliatus ssp. coloratus, aromatic plant, spontaneous and widespread in the Mediterranean and in northern Algeria is widely used by local people for its medicinal properties. Phytochemical tests applied for Thymus sciliatus ssp coloratus showed the presence of several families of chemical compounds including flavonoïds. The in vitro antioxidant activity of flavonoïds extract was evaluated by the iron reduction technique "FRAP" (ferric reducing antioxidant power) and DPPH test. The first method showed that the ethyl acetate fraction of the aerial part has an ability to reduce the iron greater than ascorbic acid and BHA and the roots, is significantly lower. As for butanol fractions of flavonoïds from the aerial part and roots, they have an ability to reduce iron significantly lower than those of ascorbic acid and BHA. The antioxidant activity obtained by the second method and on the ethyl acetate fraction of flavonoïds from the aerial part of the plant is more important (I.C₅₀ = 0.85 mg / mL) than those obtained from 'antioxidants used in food and pharmaceutical industries namely ascorbic acid (I.C₅₀ = 1.12 mg / mL) and BHA (I.C₅₀ = 1.61 mg / mL).Keywords : Thymus coloratus, antioxidant activity, flavonoïd, FRAP, DPPH

    The human phosphotyrosine signaling network: evolution and hotspots of hijacking in cancer.

    Full text link
    Phosphotyrosine (pTyr) signaling, which plays a central role in cell-cell and cell-environment interactions, has been considered to be an evolutionary innovation in multicellular metazoans. However, neither the emergence nor the evolution of the human pTyr signaling system is currently understood. Tyrosine kinase (TK) circuits, each of which consists of a TK writer, a kinase substrate, and a related reader, such as Src homology (SH) 2 domains and pTyr-binding (PTB) domains, comprise the core machinery of the pTyr signaling network. In this study, we analyzed the evolutionary trajectories of 583 literature-derived and 50,000 computationally predicted human TK circuits in 19 representative eukaryotic species and assigned their evolutionary origins. We found that human TK circuits for intracellular pTyr signaling originated largely from primitive organisms, whereas the inter- or extracellular signaling circuits experienced significant expansion in the bilaterian lineage through the back-wiring of newly evolved kinases to primitive substrates and SH2/PTB domains. Conversely, the TK circuits that are involved in tissue-specific signaling evolved mainly in vertebrates by the back-wiring of vertebrate substrates to primitive kinases and SH2/PTB domains. Importantly, we found that cancer signaling preferentially employs the pTyr sites, which are linked to more TK circuits. Our work provides insights into the evolutionary paths of the human pTyr signaling circuits and suggests the use of a network approach for cancer intervention through the targeting of key pTyr sites and their associated signaling hubs in the network

    The human phosphotyrosine signaling network: Evolution and hotspots of hijacking in cancer

    Get PDF
    Phosphotyrosine (pTyr) signaling, which plays a central role in cell-cell and cell-environment interactions, has been considered to be an evolutionary innovation in multicellular metazoans. However, neither the emergence nor the evolution of the human pTyr signaling system is currently understood. Tyrosine kinase (TK) circuits, each of which consists of a TK writer, a kinase substrate, and a related reader, such as Src homology (SH) 2 domains and pTyr-binding (PTB) domains, comprise the core machinery of the pTyr signaling network. In this study, we analyzed the evolutionary trajectories of 583 literature-derived and 50,000 computationally predicted human TK circuits in 19 representative eukaryotic species and assigned their evolutionary origins. We found that human TK circuits for intracellular pTyr signaling originated largely from primitive organisms, whereas the inter- or extracellular signaling circuits experienced significant expansion in the bilaterian lineage through the back- wiring of newly evolved kinases to primitive substrates and SH2/PTB domains. Conversely, the TK circuits that are involved in tissue-specific signaling evolved mainly in vertebrates by the back-wiring of vertebrate substrates to primitive kinases and SH2/PTB domains. Importantly, we found that cancer signaling preferentially employs the pTyr sites, which are linked to more TK circuits. Our work provides insights into the evolutionary paths of the human pTyr signaling circuits and suggests the use of a network approach for cancer intervention through the targeting of key pTyr sites and their associated signaling hubs in the network. © 2012, Published by Cold Spring Harbor Laboratory Press

    Functional outcomes in adult patients with herpes simplex encephalitis admitted to the ICU: a multicenter cohort study

    Get PDF
    PURPOSE: We aimed to study the association of body temperature and other admission factors with outcomes of herpes simplex encephalitis (HSE) adult patients requiring ICU admission. METHODS: We conducted a retrospective multicenter study on patients diagnosed with HSE in 47 ICUs in France, between 2007 and 2017. Fever was defined as a body temperature higher or equal to 38.3 °C. Multivariate logistic regression analysis was used to identify factors associated with poor outcome at 90 days, defined by a score of 3-6 (indicating moderate-to-severe disability or death) on the modified Rankin scale. RESULTS: Overall, 259 patients with a score on the Glasgow coma scale of 9 (6-12) and a body temperature of 38.7 (38.1-39.2) °C at admission were studied. At 90 days, 185 (71%) patients had a poor outcome, including 44 (17%) deaths. After adjusting for age, fever (OR = 2.21; 95% CI 1.18-4.16), mechanical ventilation (OR = 2.21; 95% CI 1.21-4.03), and MRI brain lesions > 3 lobes (OR = 3.04; 95% CI 1.35-6.81) were independently associated with poor outcome. By contrast, a direct ICU admission, as compared to initial admission to the hospital wards (i.e., indirect ICU admission), was protective (OR = 0.52; 95% CI 0.28-0.95). Sensitivity analyses performed after adjustment for functional status before admission and reason for ICU admission yielded similar results. CONCLUSIONS: In HSE adult patients requiring ICU admission, several admission factors are associated with an increased risk of poor functional outcome. The identification of potentially modifiable factors, namely, elevated admission body temperature and indirect ICU admission, provides an opportunity for testing further intervention strategies
    • …
    corecore