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Background: Normal reference values in healthy subjects for T-lymphocytes for both types of receptors, αβ and γδ, and their subsets are yet to be defined. The aim of this study was to measure peripheral blood αβ and γδ total T-lymphocytes and their subsets in a population of healthy subjects, in order to obtain valid reference values for studies in human pathology. Methods: We studied a total of 157 healthy subjects, 78 men and 79 women, establishing their levels of CD3+, CD4+, CD8+, CD56+, αβCD3+, αβCD3+CD4+, αβCD3+CD8+, αβCD3+CD56+, γδCD3+, γδCD3+CD4−CD8−, γδCD3+CD8+, and γδCD3+CD56+ T-cells by flow cytometry. The T-cell subsets were compared for different age and gender groups. Results: A significant decrease in CD3+, CD3+CD4+, CD3+CD4+ αβ, and CD3+ γδ T-cells was observed in elderly subjects. CD3+, CD3+ αβ, and CD3+CD4+ αβ T-cells increased in women, while CD3+CD56+ αβ T-cells increased in men. Conclusions. These reference values could be useful in further research studies for assessing changes that occur in the different αβ and γδ T subsets in human pathology. © 2012 International Clinical Cytometry Society

Core needle biopsy is increasingly replacing excisional lymph node biopsy in the diagnosis and subclassification of malignant lymphomas, with obvious advantages in terms of morbidity and costs. This technique has radically altered the diagnostic strategy of enlarged lymph nodes at our institution, avoiding unnecessary nodal excisions. It represents a viable alternative as long as the number and size of cores for morphologic and molecular studies are not compromised. This quick and safe technique can be applied to the initial diagnostic evaluation of malignant lymphomas as well as the reassessment of previously diagnosed malignant lymphomas at time of progression or recurrence.

Les techniques de biopsies guidees par imagerie constituent une alternative raisonnable a l’exerese chirurgicale ganglionnaire dans le diagnostic d’une hemopathie lymphoide, a condition de realiser de multiples prelevements de grande taille, dont certains seront congeles pour des etudes moleculaires eventuelles.

International audience; Two preliminary experiments show that a non-equilibrium situation can be easily encountered during a natural drying process. This leads us to reconsider the thermodynamic local equilibrium assumption, and propose a macroscopic two-equation model that takes into account mass exchange kinetics between the liquid and vapour phase. Numerical simulation of this theoretical model is then compared to experimental drying kinetics of soil columns. The discrepancies observed between the theoretical prediction and the experimental results are discussed. This contribution emphasizes the importance of such non-equilibrium phenomenon when modelling water transport in hygroscopic porous media.

A theoretical and experimental analysis of the phase change of a volatile liquid in an unsaturated soil is presented. Expression of the rate of phase change of the pore liquid is developed within the framework of nonequilibrium thermodynamics. An experiment is proposed in which the value of the phenomenological coefficient associated with this expression is measured. Two examples of results concerning the volatilisation of water and of a volatile hydrocarbon in a silty clayey sand illustrate the potentiality of the experiment. Variation of the phase change coefficient was determined at 30°C for both fluids and at 80°C for heptane, versus the liquid content of the soil.

This anick concerns the convective drying of natural rubber in granule form and aims at improving production. Parts of the research have already been published. With a validated mathematical model, il is possible to know the properties of the medium at any moment and for any point in the tayer. The research led to a simulation program for a zone-type industrial dnjir. The simulation program was used in an exhaustive study of the influence of the drying pifttfmeters for the design of a prototype industrial drier.

A model taking into account the simultaneous influence of mechanical and hygrometric actions (Mrani and al., 1995a, 1995b) was applied to study of the dehydration of a cylinder of highly deformable biphase gel (agar gel) (Mrani and al., 1995b). Numerical solution of the water transport equation and the mechanical equilibrium equation provided access to the water content and stresses and strains in the cylinder. The numerical results were validated for water content and overall deformation of gel cylinders. The model clearly shows the inversion of the curve of the faces of the cylinder observed experimentally. Three deformation phases were observed. In the first phase, when the concaveness of the faces of the cylinder was turned inwards, tractive stress appeared at the surface of the sample. More uniform distribution of the water content became established in a second phase and the cylinder recovered its initial shape corresponding to the relaxation of the stress state. In the third phase, the con...

A phenomenological equation is established for water transport in a biconstituent, isotropic, isothermal elastic medium. The equation includes a term related to the water content gradient and a term related to the deformation gradient. It is shown that in the case of an infinite plate, the transport law can be similar to Fick’s law in which water flux is proportional to the water content gradient alone. The apparent transport coefficient then depends on the hygroscopic and rheological coefficients of the medium. Experimental analysis of the evolution of water content profiles of agar gel plates validates this transport law and makes it possible to deduce the variation in apparent transport coefficient according to water content. Transport coefficients associated with water content and deformation gradients and applicable to any geometrical features are deduced.

Cette etude aborde la mesure des proprietes d'un biopolymere, le gel d'agar, au cours d'un processus de deshydratation. La morphologie du gel est mise en evidence par des observations au microscope electronique en utilisant une technique de cryofracture ; il est montre que la morphologie initiale diphasique du gel d'agar est preservee lors de l'evolution de la teneur en eau. L'etude des proprietes hygroscopiques du gel, par la determination de l'isotherme de desorption, permet, en particulier, de situer le domaine hygroscopique du materiau. On etudie ensuite le retrait du gel d'agar, par la determination des variations du coefficient de contraction et du coefficient d'expansion hygrometrique, en fonction de l'humidite du milieu. On aborde enfin l'etude rheologique du gel qui presente un comportement macroscopique elastique. La variation du module de Young en fonction de la teneur en eau est determinee par des essais de compression simple. Ce resultat est ensuite combine a des mesures de la vitesse de propagation d'ondes ultrasonores pour determiner la variation du coefficient de Poisson avec la teneur en eau.

An analysis of convective drying of natural rubber in granule form. Exploitation of the mathematical model developed from analysis of internal transfers requires determination of the ‘drying rate’ and the ‘energy exchange coefficient’ between the material and the drying air. This was performed using a portable laboratory drier at the production site, avoiding the problem of changes in the material during transport. Analysis of the drying kinetics of material in thin layers led to modelling the drying rate at the temperatures, rates and relative humidity values encountered in industrial driers. The energy exchange coefficient was found by measurement of air and granule temperatures. Thick layer trials showed the suitability of the model for simulation of changes in moisture content and temperature of air and granules in a granular environment. The study as a whole led to the development of a computer program for simulating a zone drier. This software can be used to optimise the management of an in...

The mathematical model proposed enables the description of mass and energy transfers during convection drying of granular materials. It shows evolution of the water content of the material in time and space, air and grain temperature, relative humidity of intergranular air, settling of the layer. mass energy and mass power input. Operation of the model requires experimenral determination of the water exchange coefficient between the material and drying air using thin layer drying kinetics. The software proposed enables the simulation of thick layers of granular material, as in an industrial drier. It is applied to the drying of natural rubber, taking into account the characteristics of the drying air and the flux direction in each drier zone. The aim of simulation is to optimise drying panmeters for improvement of the management and possibly the design or industrial driers.

ABSTRACT A numerical model of isothermal drying of deformable substances is proposed. The model is applied in a uni-directional case to analysis of water transport in a sphere of agar ge. The simulation program makes it possible to calculate the water content fields and def rmations and stresses in the sphere during drying. Validation of the water content profile results is proposed by the experimental study of the dehydration of gel spheres in a sugar solution. The sensitivity of internal stresses to drying conditions is then analysed.

Within the framework of a procedure for scale-changing by averaging a representative elementary volume, theorems are developed to relate the averages of derivatives to the derivatives of averages over a surface, using elementary differential calculus. These theorems form the basis of a general macroscopic balance equation for a given quantity over interfaces of a dispersed multiphase medium. The equations of phase interfaces complement equations related to bulk phases describing transport in dispersed multiphase media.

Three multivariate techniques (principal components analysis, correspondence factor analysis and spectral map analsis) are applied to x-ray fluorescence data from glass-making objects from the 5th century AD found in Tarragona (Tarraco in the Roman Empire). The information obtained by displaying th eobjects and variables in each reduced factor space is compared. The presence of redundant information is shown. The visualization of groups of objects and of the relationship between objects and variables allows the formulation of hypotheses concerning the origin of the samples and the presence of local glassworks.

On propose une methode d'elaboration de modeles mathematiques permettant d'aborder les applications liees a l'exploitation thermique du sous-sol. Cette methode, basee sur la thermodynamique des processus irreversibles, est illustree dans le cas du stockage de chaleur dans les sols non satures. On presente les resultats experimentaux d'une aire d'essai de stockage de chaleur ; ces resultats sont utilises pour : 1) Analyser les modifications provoquees par le stockage dans la couche de sol non saturee. 2) Valider le modele mathematique et proposer un modele simplifie du site de stockage.

Nous etudions la mesure de la conductivite thermique des sols a l’aide d’une sonde cylindrique en regime transitoire et nous examinons en particulier l’influence des conditions de mise en place de la sonde.

The purpose of this work was to elaborate a mathematical model describing the evolution of non-saturated soil used as a heat storage medium. The high temperatures encountered in this application lead to important elementary phenomena as far as heat and mass transfer are concerned but which are often negligible at ambient temperatures.

The aim of the project is to study the mass and energy transfers in a non-saturated layer of soil placed above a saturated layer.

The efficiency of energy storage in a saturated layer is linked to a great extend to the energy and matter losses through the non-saturated layer of soil lying above the saturated layer used as a storage zone. In order to study this problem we constructed a physical model of sufficiently large size. A test programme has made it possible to simulate heat storage at 60° C. The surface of the soil was subjected to controlled conditions and then natural atmospheric conditions. The physical model serves as a prototype for the study of the behaviour of a natural site. The evolutions of the physical model make it possible to judge the modifications in the state of the non-saturated layer of soil and to come to conclusions regarding possible harmful effects of storage. The physical model has given experimental results that confirm the validity of a local three-phase mathematical model. This confirmation allows this model to be used in the future for making forecasts for other sites.