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Depuis plusieurs années, une recrudescence de la syphilis est décrite à La Réunion. L’épidémiologie y est caractérisée par une atteinte prépondérante chez des patients hétérosexuels avec de nombreuses femmes en âge de procréer infectées. La syphilis congénitale est donc un problème de santé publique sur cette île. La contre-indication à la doxycyline pendant la grossesse et les ruptures d’approvisionnement en benzathine benzylpénicilline nécessitent d’envisager d’autres thérapeutiques. L’azithromycine peut être une alternative dans certains cas. Cependant, la mutation A2058G du gène de l’ARN23Sconfère à Treponemapallidum(TP) une résistance à cet antibiotique. Afin de pouvoir envisager un traitement de masse dans ce département, nous avons cherché la présence de cette résistance dans les prélèvements positifs.

Activity coefficients at infinite dilution of 31 organic compounds in three room-temperature ionic liquids (RTILs) were determined using inverse gas chromatography. The measurements were carried out at different temperatures between 313.15 and 333.15 K. The regular solution theory was used to estimate the solubility parameters of each RTIL. Such a theory was also used to predict the CO2 solubility in a given RTIL and to estimate the upper critical solution temperature of a binary system containing 1-butanol and 1-butyl-3-methylimidazolium hexafluorophosphate. The accuracy of the results obtained indicates that the regular solution theory is a good tool to predict the phase behavior of mixtures containing RTILs.

Adsorption isotherms of two volatile organic compounds, toluene and m-xylene, on dealuminated Y zeolite (DAY) were measured at (25, 35, 45, and 55) °C using a vacuum microbalance system. The experimental data obtained were correlated with different existing adsorption isotherm models such as the Langmuir model and the Freundlich model.

Gas injection processes are among the most effective methods for enhanced oil recovery. A key parameter in the design of a gas injection project is the minimum miscibility pressure (MMP), the pressure at which the local displacement efficiency approaches 100%. From an experimental point of view, the MMP is routinely determined by slim tube displacements. However, because such experiments are very expensive (time-consuming), the question we want to answer in this article is as follows:  Is this still necessary to measure the MMP? In other words, may other quicker, easier and cheaper gas injection experiments such as swelling test or multicontact test (MCT) substitute for slim tube test? This paper concludes that when the injected gas is not pure CO2 (and probably not pure N2 or pure H2S), it is enough to fit only two parameters of the equation of state on data including classical PVT data + swelling data + MCT data and then to predict the MMP. The accuracy obtained is similar to the experimental uncertainty. It is thus possible to conclude that the slim tube test may be replaced by swelling tests and MCT, which are much cheaper.

In this work, the first enantioseparation in a SF-SMB unit, i.e., a simulated moving bed (SMB) operated under supercritical conditions, is reported. Complete separation of the two enantiomers of tetralol was achieved both in the pressure-gradient mode (where a pressure gradient is imposed along the four sections of the unit) and in the isocratic mode (where the pressure is kept constant). However, an almost 3-fold increase in productivity could be achieved in the pressure-gradient rather than the isocratic mode. The obtained results are explained and rationalized using recently developed design criteria for SMBs, the so-called “triangle theory”, which have been properly extended to allow for different pressure values in the different sections of the unit.

The ternary system CO2−limonene−citral was chosen as a model system in order to study the extraction of terpenes from lemon oil using supercritical carbon dioxide. Extractions were performed at several pressures and temperatures to evaluate the influence of these parameters on the separation efficiency. Extract composition was monitored by capillary gas chromatography. A theoretical model, based on a modified Peng−Robinson equation of state, was used to simulate the thermodynamic and mass transfer aspects of the extraction column. The critical parameters and the acentric factors of limonene and citral were estimated by group contribution methods. The method developed by Abdoul et al., which allows the calculation of binary interaction parameters (kij), was applied to terpenic compounds. The extraction experiments were simulated using this model, and the extraction profiles were accurately reproduced.

In this paper, a compositional model is proposed to calculate the phase behavior and the physical properties of condensate gases. Such a model is based on a very classical and easy to handle cubic equation of state coupled with correlations devoted to the estimation of the hydrocarbon physical properties. Moreover, to completely define the composition of the C20+ distillation residue, three distribution functions associated with the families n-alkanes, n-alkylbenzenes, and polyaromatics are introduced. The method developed in this work shows clearly enhanced results in comparison to previously published papers in the same area.

Adsorption isotherms of toluene on activated carbon were measured by time integration of the breakthrough curves at 298.15 K and 308.15 K using an apparatus developed for this purpose. Isotherms were also measured at 318.15 K and 333.15 K using a microbalance. Activated carbon was used as the adsorbent because it typically exhibits high adsorption capacities and shows potential as an adsorbent to effectively remove volatile organic compounds (VOCs) such as toluene. The experimental data were correlated with the following adsorption isotherms:  Langmuir, Freundlich, Toth, and Dubinin. All these models except the Langmuir model were able to correlate our data.

Very recently, Jaubert et al. proposed a purely predictive model for the phase equilibria computation of mixtures involving fatty acid esters (FAE) and supercritical carbon dioxide (SC−CO2). In this research note, the capability of the model to predict the isothermal phase diagrams of three binary systems recently measured by Crampon et al. is checked. The results obtained are very encouraging because the proposed model is able to predict the experimental bubble-point and dew-point pressures with an average deviation of 7%.

In this paper, an easily computable algorithm, allowing the calculation of the minimum miscibility pressure (MMP) whatever the displacement mechanism, is described. Such an algorithm is based on a multiple mixing cell calculation without any porous media. Only thermodynamic equations are taken into account i.e., a P/T flash routine is only required. Computational speed is from 15 to 80 times faster than using a commercial one-dimensional (1D) simulator, but the accuracy is the same.

In this paper, real crude oils are dealt with which are modeled with an average of 30 components. On the selected examples, neither the initial tie line, i.e., the tie line that extends through the original oil composition, nor the gas tie line, i.e., the tie line that extends through the injected gas composition, controls the miscibility process. In any case, the miscibility process is controlled by one of the (nc − 3) crossover tie lines, if nc is the number of components in the crude oil. However, it is shown that the miscibility process may be a pure vaporizing gas drive mechanism (VGDM). To be more precise, it is shown that a mixed condensing/vaporizing mechanism may, with increasing pressure, turn into a pure VGDM. This means that the classical definition of a VGDM, i.e., the lowest pressure at which the initial tie line is critical, must be changed. This is the main point of this paper. In the case of a VGDM controlled by a crossover tie line, the MMP (the lowest pressure at which the key crossover tie line becomes critical) may still be computed by a one cell simulation algorithm. Another aim of this paper is to explain what really happens during a one cell simulation and to give proof that such an algorithm may not make critical the initial or the gas tie line.

In this paper, a purely predictive model for the phase equilibria computation of mixtures involving fatty acids (FA) and supercritical carbon dioxide (SC-CO2) is proposed. In a first step, the phase equilibria modeling of FA/CO2 binary systems were performed using the Peng−Robinson equation of state. To obtain a purely predictive model, the group contribution method developed by Abdoul et al. which allows the prediction of the binary interaction parameters (kij) was extended to FA compounds. In a second step, the proposed model was used to predict the phase equilibria data of ternary and quaternary systems found in the literature. In a last step, bubble-point and dew-point pressures of systems involving CO2 and multicomponent mixtures of FA were measured in our laboratory, and the previous model was used in order to check its capability in predicting these data.

In this paper, a purely predictive model for the phase equilibria computation of mixtures involving fatty acid esters (FAE) and supercritical carbon dioxide is proposed. In a first step, the phase equilibria modeling of FAE/CO2 binary systems were performed using the Peng−Robinson equation of state. To obtain a purely predictive model, the critical properties (Tc, Pc) and the acentric factor (ω) of the FAE were estimated with specific correlations. Moreover, the group contribution method developed by Abdoul et al., which allows the prediction of binary interaction parameters (kij), was extended to ester compounds and an additional group (the ester function) was defined. Such an approach allowed us to correlate with quite good accuracy all the binary FAE/CO2 systems. In a second step, dew points of (CO2/fish oil) systems were measured and the previous model was used to check its capability in predicting these data. The fish oil under study contained 30 different fatty acid ethyl esters, and the model was able to predict with very good accuracy the measured saturation pressures.

Hemoglobin Grange‐Blanche [β27(B9) Ala → Val] is a new variant found in a Portuguese family. The carriers present moderate erythrocytosis. Upon isoelectric focusing, Hb Grange‐Blanche was slightly more cathodic than Hb A. βGrange‐Blanchechain migrated like the Gγ chain when submitted to electrophoresis in the presence of urea‐Triton X‐100. The precentage of Hb Grange‐Blanche was about 50% in the heterozygous state. Oxygen affinity was increased (P50= 22 mmHg), but heme‐heme interaction was normal. An abnormal tryptic peptide (βT3) was isolated using HPLC. Its composition allowed us to deduce unambiguously the amino acid change. The latter is the third mutation found in position 27 of the β‐chain. Because of its normal expression and its elevated affinity for oxygen, Hb Grange‐Blanche contrasts with Hb Knossos [β27(B9) Ala → Ser], a β‐thalassemic variant with low affinity.

L’infection à Chlamydia trachomatis(CT) est l’infection sexuellement transmissible bactérienne la plus répandue dans le monde. Souvent asymptomatique, elle peut se compliquer de séquelles chez la femme. En France, depuis 2003, il est préconisé un dépistage systématique du CTdans les centres de dépistage chez les femmes de moins de 25 ans. Le réseau « RésIST-Réunion » permet la surveillance de la syphilis, de la gonococcie et de la lymphogranulomatose rectale. Les réseaux de laboratoires dédiés aux infections à chlamydiae et gonocoque n’ont pas été mis en place à la Réunion. L’objectif principal de cette étude est de déterminer la prévalence de CTchez les patientes consultant en centre de dépistage à la Réunion. L’objectif secondaire est d’affiner les données épidémiologiques associés à cette infection.

La syphilis est une infection sexuellement transmissible dont la prévalence mondiale est estimée à 0,5 % en 2012. Alors que la syphilis est en augmentation dans la littérature nationale et internationale dans les pays développés parmi les hommes ayant des rapports sexuels avec des hommes, la situation semble différer à la Réunion. L’objectif était de déterminer la prévalence de la syphilis,ses caractéristiques cliniques et ses facteurs de risque dans un centre gratuit d’information, de dépistage et de diagnostic des infections sexuellement transmissibles du sud de la Réunion.