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Measurement of total phenolic content and antioxidant activity of aerial parts of medicinal plant Coronopus didymus

Asian Pacific Journal of Tropical Medicine 2017年第8期10卷 855-862页

作者： Hafiza Noreen Nabil Semmar Muhammad Farman James S.O.McCullagh department of Chemistry Quaid-i-Azam UniversityIslamabad 45320Pakistan institut supérieur des sciences biologiques appliquées de tunis Tunisia Chemistry Research Laboratory Department of ChemistryUniversity of OxfordMansfield RoadOxford OX1 3TAUnited Kingdom

Objective: To evaluate the total phenolic content and compare the antioxidant activity of various solvent extracts and fractions from the aerial parts of Coronopus didymus through various assays. Methods: Total phenolic content was determined using the Folin-Ciocalteu assay and the in vitro antioxidant activity of a number of different extracts was investigated in a dose-dependent manner with three different methods: the 2,2-diphenyl-1-picrylhydrazyl(DPPH), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt(ABTS) and ferric reducing antioxidant power(FRAP) assays. A flavone was isolated from the most active ethanolic extract with high antioxidant activity using size exclusion chromatography. IC_(50) values were calculated for the DPPH and ABTS methods. The FRAP activity was assessed in terms of μM Fe(II) equivalent. Results: The phenolic content was found to be highest in the ethanol extract(CDA Et; 47.8 mM GAE) and the lowest in the dichloromethane extract(CDA DCM; 3.13 mM GAE). The ethanol extract showed high radical scavenging activity towards DPPH and ABTS radicals with IC_(50) values of(7.80 × 10~2) and(4.32 × 10~2) μg/m L, respectively. The most active ethanol extract had a FRAP value of 1 921.7 μM Fe(Ⅱ) equivalent. The isolated flavone F10C(5,7,4'-trihydroxy-3'-methoxy flavone) was far more effective for scavenging free radicals in the DPPH and ABTS assays with IC_(50) of 43.8 and 0.08 μg/m L, than the standard trolox, with IC_(50) values of 97.5 and 21.1 μg/m L, respectively. In addition, the flavone F10C and the standard ascorbic acid had FRAP values of 1 621.7 and 16 038.0 μM Fe(Ⅱ) equivalents, respectively. Conclusions: The total phenolic content of extracts in decreasing order is ethanol extract(CDA Et)> acetone extract(CDA ACE)> phenolic extract(CDA MW)> n-hexane extract(CDA nHX)> chloroform extract(CDA CHL)> dichloromethane extract(CDA DCM). The ordering of extracts in terms of antioxidant activity from highest to lowest is CDA Et> C

关键词： Coronopus didymus Antioxidant activity Total phenolic content Size exclusion chromatography

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Online conflict resolution strategies for human activity recognition in smart homes

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Journal of Control and decision 2023年第3期10卷 402-416页

作者： Amina Jarraya Amel Bouzeghoub Amel Borgi Facultédes sciences de tunis Universitéde Tunis El ManarTunisTunisia Samovar Télécom SudParisInstitut Polytechnique de ParisPalaiseauFrance Facultédes sciences de tunis Institut Supérieur d’InformatiqueUniversitéde Tunis El ManarTunisTunisia

DCR-OL is a Distributed Collaborative Reasoning multi-agent model with an Online Learning thataims to identify human activities in smart homes from distributed, heterogeneous and dynamicsensor data. In this model, distributed learning agents with diverse classifiers, detect sensorstream data, make local predictions, communicate and collaborate to identify current ***, they learn from their collaborations to improve their own performance in activity *** resolution strategies are applied to generate one final predicted activity when thelocal predicted activity of an agent is different from received predicted activities of other *** this paper, two conflict resolution strategies using online learning, w-max-trust and w-maxfreq,are proposed. We experimentally test these strategies by performing an evaluation studyon the Aruba dataset. The obtained results indicate an enhancement in terms of accuracy and Fmeasuremetrics compared to the offline strategies max-trust and max-freq and also to the onlineexisting one max-wPerf .

关键词： Human activity recognition distributed reasoning learning agents smart homes online learning conflict resolution strategies sensor data stream

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BesT APPROXIMATION FOR WEIERSTRASS TRANSFORM CONNECTED WITH SPHERICAL MEAN OPERATOR

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Acta Mathematica Scientia 2012年第2期32卷 455-470页

作者： L.T.Rachdi N.Msehli Département de Math'ematiques Facult'e des Sciences de Tunis2092 El-ManarTunisia Département de Mathématiques et d'informatique Institut National des Sciences Appliquées et de Technologie de Tunis1080 TunisTunisia

Using reproducing kernels for Hilbert spaces, we give best approximation for Weierstrass transform associated with spherical mean operator. Also, estimates of extremal functions are checked.

关键词： Weierstrass transform spherical mean operator best approximation repro-ducing kernel extremal function

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TiO_2 nanotubes as solid-phase extraction adsorbent for the determination of polycyclic aromatic hydrocarbons in environmental water samples

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Journal of Environmental sciences 2011年第5期23卷 860-867页

作者： Bochra Bejaoui Kefi Latifa Latrous El Atrache Hafedh Kochkar Abdelhamid Ghorbel Laboratoire des Matériaux Utiles Institut National de Recherche et d'Analyse Physico-chimiqueple technologique Sidi-Thabet 2020 Tunis Tunisia Laboratoire de Chimie Analytique et Electrochimie Département de Chimie Facultédes Sciences de TunisCampus Universitaire2092 EL Manar TunisTunisia Laboratoire de Chimie des Matériaux et Catalyse Facultédes Sciences de TunisCampus Universitaire2092 EL Manar Tunis Tunisia

An analytical method based on TiO2 nanotubes solid-phase extraction （SPE） combined with gas chromatography （GC） was established for the analysis of seven polycyclic aromatic hydrocarbons （PAHs）： acenaphtylene, acenaphthene, anthracene, fluorene, phenanthrene, fluoranthene and pyrene. Factors affecting the extraction efficiency including the eluent type and its volume, adsorbent amount, sample volume, sample pH and sample flow rate were optimized. The characteristic data of analytical performance were determined to investigate the sensitivity and precision of the method. Under the optimized extraction conditions, the method showed good linearity in the range of 0.01-0.8 μg/mL, repeatability of the extraction （RSD were between 6.7% and 13.5%, n = 5） and satisfactory detection limits （0.017-0.059 μg/mL）. The developed method was successfully applied to the analysis of surface water （tap, river and dam） samples. The recoveries of PAHs spiked in environmental water samples ranged from 90% to 100%. All the results indicated the potential application of titanate nanotubes as solid-phase extraction adsorbents to pre-treat water samples.

关键词： Ti02 nanotubes hydrothermal treatment solid phase extraction gas chromatography polycyclic aromatic hydrocarbons

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Exact Solution of D-Dimensional Klein-Gordon Oscillator with Minimal Length

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Communications in Theoretical Physics 2010年第2期53卷 231-236页

作者： Y.Chargui L.Chetouani A.Trabelsi Unit de Recherche de Physique Nuclaire et des Hautes Energies Facult des Sciences de Tunis Dpartement de Physique Thorique Institut de Physique Universit de Constantine Route Ain El Bey Unite de Recherche de Physique Nucleaire et des Hautes Energies Faculte des Sciences de Tunis Centre National des sciences et Technologies Nuclaires

Specific modifications of the usual canonical commutation relations between position and momentumoperators have been proposed in the literature in order to implement the idea of the existence of a minimal observablelength. Here, we study a consequence of this proposal in relativistic quantum mechanics by solving in the momentumspace representation the Klein-Gordon oscillator in arbitrary dimensions. The exact bound states spectrum and thecorresponding momentum space wave function are obtained. Following Chang et al. (Phys. Rev. D 65 (2002) 125027),we discuss constraint that can be placed on the minimal length by measuring the energy levels of an electron in a penningtrap.

关键词： Klein-Gordon oscillator minimal length energy spectrum

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Physiological Responses of Pea Plants to Salinity and Gibberellic Acid

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Phyton-International Journal of Experimental Botany 2023年第1期92卷 149-164页

作者： Houneida Attia department of Biology College of ScienceTaif UniversityTaif21944Saudi Arabia Laboratoire ProductivitéVégétale et Contraintes Environnementales Département des Sciences BiologiquesFacultédes Sciences de TunisUniversitéTunis El ManarTunis2092Tunisia

Pea is a seed *** is rich in cellulose fibre and *** is also a significant source of minerals and *** this paper,we set out to better characterize the physiological responses of Pisum sativum *** the combined effects of NaCl,100 mM and gibberellins(GA3).Our analysis revealed that NaCl caused a decrease in growth resulting in a reduction in root elongation,distribution and density,leaf number and leaf area,and a decrease in dry matter of roots and ***,the contribution of GA3 in the salty environment induced an increase in these different parameters suggesting an improving effect of this hormone on growth of pea in presence of *** also led to a disturbance of the photosynthetic ***,level of chlorophyll pigments(a and total)and photosynthetic activity were decreased compared to the control ***,the exogenous supply of GA3 restored this decrease in net CO_(2) assimilation,but not in chlorophyll *** analyses were performed on the effect of salinity/GA3 interaction on osmolytes(soluble sugars and starch).Our results showed an increase in sugars and a decrease in starch in the presence of 100 mM *** salt-GA3 combination resulted in compensation of soluble sugar contents but not of starch contents,suggesting a beneficial effect of GA3 under saline stress *** of three main polyamines putrescine,spermidine,and spermine increased significantly in all organs of salt-treated plants.

关键词： Pisum sativum L. salinity gibberellic acid growth sugars polyamines

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Mid/far-infrared photo-detectors based on graphene asymmetric quantum wells

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Chinese Physics B 2016年第9期25卷 573-580页

作者： E Ben Salem R Chaabani S Jaziri institut Preparatoire aux Etudes d'Ingenieurs de tunis 2 Rue Jawaher Lel Nahrou Monfleury 1089 Tunisie Laboratoire de Physique de la Matiere Condensee Departement de Physique Faculte des Sciences de Tunis Campus Universitaire 2092 Tunisie departement de Physique Faculte des Sciences de Bizerte Jarzouna 7021 Bizerte

We conducted a theoretical study on the electronic properties of a single-layer graphene asymmetric quantum *** of energy levels is limited by electron–hole conversion at the barrier interfaces and free-electron ***–hole conversion at the barrier interfaces can be controlled by introducing an asymmetry between barriers and taking into account the effect of the interactions of the graphene sheet with the *** interaction with the substrate induces an effective mass to carriers,allowing observation of Fabry–P′erot resonances under normal incidence and extinction of Klein *** asymmetry,between barriers creates a transmission gap between confined states and free-electron continuum,allowing the large graphene asymmetric quantum well to be exploited as a photo-detector operating at mid-and far-infrared frequency regimes.

关键词： graphene quantum wells reflection coefficient photo-detector

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A Thermo-Mechanical Behavior Simulation of A NiTi Staple Used for the Correction of Idiopathic Scoliosis

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Journal of Biomaterials and Nanobiotechnology 2012年第1期3卷 61-69页

作者： Fafa Ben Hatira Kaouthar Saidane institut National des sciences appliquées et de Technologie (INSAT) Université de Carthage Tunis Tunisia

In order to treat scoliosis, a thermo-mechanical behavior study of shape memory alloy bone staple has been proposed. A pre-stretched shape-memory-alloy bone staple, which has been heated above the transition temperature, provides greater compressive force upon insertion between two vertebrae and allows the control of idiopathic scoliosis development. Until now, the optimal design has not been reached due to the lack of appropriate design tools for shape memory alloy devices. In this paper, a shape memory alloy bone staple model is proposed by developing a user subroutine UMAT based on Boyd et al. unified thermodynamic shape memory alloy constitutive law using the finite element analysis software, ABAQUS. The numerical results for superelastic and shape memory effect under the tensile and three-point bending tests are presented. Simulations of the shape memory effects and force generation of the shape memory alloy staple are also shown.

关键词： Shape Memory Alloy Constitutive Law Finite Element Modeling Idiopathic Scoliosis Staple

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Epistasis and Maternal Effect in Resistance to Puccinia coronata ***. avenae Eriks in Oats(Avena sp.)

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Agricultural sciences in China 2010年第10期9卷 1462-1466页

作者： Bnejdi F Hammami I Allagui M B Saadoun M el Gazzah M Laboratoire de Génétique et Biométrie Faculté des sciences de tunis Université Tunis institut National de la Recherche Agronomique de tunisie(INRAT) Rue Hadi Karray

The objective of this paper was to investigate the mode of heredity for resistance in oats （Avena sp.） to crown rust caused by Puccinia coronata Cda. f. sp. avenae Eriks, Eight generations of 2 crosses were used to estimate genetic effects and narrow-sense heritability （NSH）. Separate generation means analysis （GMA） indicated a complex gene action controlling this trait with additive, dominance, epistatic and maternal effects （ME）. The genetic model which assumed no epistasis and no ME did not accurately describe the resistance to P. coronata. In both crosses, the digenic epistatic model with ME was sufficient to explain variation in generation means for isolate CRec58 and isolate CRec46. Additive dominance and epistatic components were negative in most cases, suggesting that gene effects contributed more to the resistance than to the susceptibility. The estimated values of NSH were 15-99% depending upon the cross and isolates. The results indicated that appropriate choice of maternal parent and recurrent selection would increase resistance to crown rust in oats.

关键词： epistasis heritability maternal effect resistance

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Chemical composition of Rosmarinus and Lavandula essential oils and their insecticidal effects on Orgyia trigotephras(Lepidoptera,Lymantriidae)

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Asian Pacific Journal of Tropical Medicine 2015年第2期8卷 98-103页

作者： Ben Slimane Badreddine Ezzine Olfa Dhahri Samir Chograni Hnia Ben Jamaa Mohamed Lahbib institut superieur des sciences et Technologies de l'Environnement de Borj-Cédria B.P.1003Hammam-Lif 2050-Tunisia institut National de Recherche en Génie Rural Eaux et ForêtsTunis.Tunisia institut National des sciences appliquees et Technologiques.tunis.tunisia

Objective:To evaluate toxic activities of essential oils obtained from Rosmarinus officinalis and Lavandula stoechas against the fourth larval instars of Orgyia ***:A total of 1 200 larvae were divided into three groups Ⅰ,Ⅱ,Ⅲ.Group Ⅰ was to investigate the effect of extracted essential oils from these aromatic plants as gastric *** thuringiensis and ethanol were used as control *** Ⅱ was used as contact action and Group Ⅲ was used as fumigant *** and ethanol were used as control *** the three experiments,the effect of essential oils on larvae was ***:The chemical composition of essential oils from two medicinal plants was determined and,their insecticidal effects on the fourth larval slate of Orgyia trigotephras were *** two simples presented an insecticidal activity,nevertheless Rosmarinus officinalis essential oil was less efficient compared to Lavandula stoechas one are ***:The relationship between the chemical composition and the biologieal activities is confirmed by the present *** the potential uses of these essential oils as bioinsecticides can he considered as an alternative to the use of synthetic products.

关键词： Rosmarinus Lavandula Orgyia trigotephras essential oils Insect control

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