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Bugaud C.,CIRAD | Deverge E.,Campus University | Daribo M.-O.,CIRAD | Ribeyre F.,CIRAD - Agricultural Research for Development | And 2 more authors.
Journal of the Science of Food and Agriculture | Year: 2011

BACKGROUND: Knowledge of the sensory diversity of a wide range of dessert bananas would be helpful in breeding programmes and so diversify the banana market. Descriptive sensory profiling was thus used to assess 13 cultivated bananas and four new triploid hybrids at an eating stage. RESULTS: A specific vocabulary was defined to describe the sensory traits of dessert bananas. The 17 cultivars assessed were ranked in five sensory clusters, which differed mainly in the intensity of sourness and sweetness. The first cluster, which contained the standard banana (Cavendish), received the lowest sourness and the highest sweetness and banana flavour scores. The second cluster was the sourest and firmest and had the highest chemical flavour score. The third cluster was characterised by the highest melting score, the fourth by the highest mealiness, astringency, grassy odour and flavour scores and the fifth by a balance between sourness and sweetness and the highest heterogeneous texture score. Firmness and sourness were correlated with rheological pulp firmness and titratable acidity respectively. CONCLUSION: The results led to the identification of relevant attributes that grouped the sensory diversity of dessert banana into five clusters. Combined with hedonic data, these results should help breeders to select banana hybrids. © 2011 Society of Chemical Industry.

Amami M.,Campus University
Industrial and Engineering Chemistry Research | Year: 2014

Crystallization of calcium sulfate dihydrate (CaSO4· 2H2O, gypsum) in sodium chloride solutions has been studied in the presence of magnesium ion. It was shown that Mg2+ has an inhibiting effect on the two stages of precipitation: nucleation and growth. Kinetic results were explained on the basis of the strong effect of magnesium ions on gypsum solubility. In the studied range of the ionic strength (IS), it was found that in the presence of NaCl the solubility increase stops beyond IS = 0.31 mol·L-1 whereas it continues to rise in the presence of MgCl2. X-ray diffraction analyses showed that magnesium ions act by substituting the calcium ones or by insertion in the defects of the gypsum crystal lattice. © 2014 American Chemical Society.

Sauvageot F.,Campus University | Herbreteau V.,Actilait | Berger M.,Insudiet | Dacremont C.,Campus University | Dacremont C.,University of Burgundy
Food Quality and Preference | Year: 2012

Fifteen groups of participants in nine laboratories performed triangle tests with two pairs of soft drinks. Groups differed in practice level with triangle tests: eight groups of 60 consumers who were not used to triangle test, three groups of qualified assessors who have already performed a few triangle tests, and four groups of trained assessors with a more extensive practice of triangle tests; qualified and trained groups included 9 or 18 assessors. The soft drinks were made from syrups at two levels of dilution in order to achieve about 55% of correct responses to test for difference and about 40% of correct responses to test for similarity. Participants performed three replicated tests with each pair of drinks, except the groups of 9 assessors who performed six replicated tests. When testing for difference, large inter-groups differences were observed. One consumer group and one trained group from two different laboratories failed by far to reach the critical number of correct responses leading to demonstrate a significant difference between products. For similarity test, all consumer groups demonstrated a significant similarity whereas two qualified groups and one trained group did not. This is explained by a slightly higher level of performance for qualified and trained assessors compared to consumers. © 2011 Elsevier Ltd.

Hernandez B.,University of Paris 13 | Pfluger F.,University of Paris 13 | Derbel N.,Campus University | De Coninck J.,Materia Nova | Ghomi M.,University of Paris 13
Journal of Physical Chemistry B | Year: 2010

In two recent reports of the same series (J. Phys. Chem. B 2007, 111, 1470-1477 and J. Phys. Chem. B 2009, 113, 3169-3178), we have described the geometrical and vibrational analysis of glycine and amino acids (AAs) with hydrophobic side chains through the joint use of optical spectroscopy and quantum mechanical calculations. Here, we report Raman scattering and Fourier-Transform Infrared (FT-IR) Attenuated Total Reflectance (ATR) spectra measured from the aqueous solutions (H2O and D2O) of L-lysine and L-arginine, i.e. two a-AAs with positively charged hydrophilic side chains. The discussion on the vibrational features of both AAs could be carried out thanks to the theoretical calculations performed by means of the Density Functional Theory (DFT) approach at the B3LYP/6-31++G* level. We have analyzed the influence of implicit (with a polarizable dielectric continuum) and explicit (by means of an H2O cluster interacating with H-donor and H-acceptor sites of AAs) hydration models. In addition, through the calculated geometrical parameters and vibrational wavenumbers, a discussion was performed on the effect of the Cl- anion interacting with the positively charged side chains of explicitely hydrated AAs. © 2010 American Chemical Society.

Jelassi R.,Campus University | Khemaissia H.,Campus University | Nasri-Ammar K.,Campus University
African Journal of Ecology | Year: 2012

During 1 year from spring 2007 to winter 2008, we conducted four seasonal samplings along a transect in the supralittoral zone of Bizerte Lagoon at Menzel Jmil (Tunisia) to study the intra-annual variation of Peracarida diversity, Talitridae and Oniscidea. For each season, one transect was studied and quadrates were placed successively from the shoreline to the road backing the shore. Talitridae and Oniscidea were the most abundant taxa in our samples reaching highest densities in summer, when fourteen species were found. The minimum and maximum values of species richness of Talitridae were observed in winter (four species) and summer (eight species), respectively, while for Oniscidea, species richness ranged from one species in winter and five species in spring. Both Talitridae and Oniscidea exhibited intra-annual variation in their spatial distribution; in that, they moved away from the shoreline in winter and were found near the waterline in the other seasons. ANOVA test shows a high significant correlation between both Talitridae with Suaeda maritima and Oniscidea with the plants S. maritima,Salicornia arabica and Obione portulacoides. © 2012 Blackwell Publishing Ltd.

Saadi C.,Campus University | Chaoui H.,Campus University
Procedia Computer Science | Year: 2016

The cloud computing security has become a basic necessity. It acquires knowledge about vulnerabilities, attacks, activities of attackers and tools to secure it. This work proposes new cloud infrastructure architecture, which combines IDS based on mobile agent sand using three types of honeypots in order to detect attacks, to study the behavior of attackers, increase the added value of Honeypot and IDS based mobile agents, solve systems limitations intrusion detection, improve knowledge bases IDS thus increase the detection rate in our cloud environment. © 2016 The Authors. Published by Elsevier B.V.

Mikael A.,Campus University | Gueguen P.,Campus University | Bard P.-Y.,Campus University | Roux P.,Campus University | Langlais M.,Campus University
Bulletin of the Seismological Society of America | Year: 2013

The characterization and monitoring of buildings is an issue that has attracted the interest of many sectors over the last two decades. With the increasing use of permanent, continuous, and real-time networks, ambient vibrations can provide a simple tool for the identification of dynamic building parameters. This study is focused on the long-term variation of frequency and damping in several buildings, using the Random Decrement Technique (RDT). RDT provides a fast, robust, and accurate long-term analysis and improves the reliability of frequency and damping measurements for structural health monitoring. This reveals particularly useful information for finding out precisely how far changes in modal parameters can be related to changes in physical properties. This paper highlights the reversible changes of the structure's dynamic parameters, correlated with external forces, such as temperature and exposure to the sun. Contrasting behaviors are observed, including correlation and anticorrelation with temperature variations.

Ruggiero J.,Campus University | Chaneliere T.,Campus University | Le Gouet J.-L.,Campus University
Journal of the Optical Society of America B: Optical Physics | Year: 2010

We investigate coherent propagation through a large optical density Tm 3+ :YAG crystal. Using an ultrastable laser, fiber filtering, and site selection, we investigate the transmitted pulse temporal profile. The plane-wave condition is satisfied by selection of the illuminated-spot central area. We pay special attention to π pulse transmission in the prospect of implementing optical quantum storage protocols. © 2009 Optical Society of America.

Stouky M.A.,Campus University | Chaoui H.,Campus University
Proceedings of 2016 SAI Computing Conference, SAI 2016 | Year: 2016

Companies operating in some areas can gather all the data they need with relative ease, more specifically marketing companies, social networks or internet companies to name but a few. However when it comes to analyzing these data, many problems may occur. Insufficient resources that can store all this flood of data or highly significant response time to get the results. In some definitions of Big Data, one of the main characteristics is Velocity as the results should be obtained quickly. This is why optimization is a top priority while working in a Big Data environment. In this paper we provide a state-of-the-art report of the main causes of performance related problems in a Big Data environment. Our study is mainly focused on Hadoop as it is free and the most popular solution when it comes to Big Data. © 2016 IEEE.

Das D.,Dinhata College | Messaadi A.,Campus University | Barhoumi Z.,Campus University | Ouerfelli N.,Campus University | Ouerfelli N.,Tunis el Manar University
Journal of Solution Chemistry | Year: 2012

Excess molar volumes, viscosity deviations, and isentropic compressibility changes in N,N-dimethylacetamide + water binary mixtures at (298.15, 308.15 and 318.15) K were calculated from experimental density, viscosity and sound velocity results presented in previous work. Here these experimental values were used to test the applicability of the correlative reduced Redlich-Kister equation and the recently proposed Herráez equation, as well as their corresponding relative functions. Their correlation ability at different temperatures, and the use of different numbers of parameters, are discussed for the case of limited experimental data. The relative functions are important to reduce the effect of temperature and, consequently, to reveal the effects of different types of interactions. Values of the limiting excess partial molar volume at infinite dilution were deduced using different methods. Also, the activation parameters and partial molar Gibbs energy of activation of viscous flow were analyzed as functions of composition. Correlation between the two Arrhenius parameters of viscosity in all composition domains show the existence of two distinct behaviors, separated by a stabilized structure over a short range of mole fractions from (0.2 to 0.3) in N,N-dimethylacetamide. In this regard, a correlation equation recently proposed by Belda has also been applied to the present system for deriving molar volume properties, in order to assess the validity of the proposed equation,. © Springer Science+Business Media, LLC 2012.

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