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Activated carbon fixed beds are classically used to remove volatile organic compounds (VOCs) present in gaseous emissions. In such use, an increase of local temperature due to exothermal adsorption has been reported; some accidental fires in the carbon bed due to the removal of high concentrations of ketones have been published. In this work, removal of VOCs was performed in a laboratory-scale pilot unit. In order to visualize the increase in local temperature, the adsorption front was tracked with a flame ionization detector and the thermal wave was simultaneously visualized with an infrared camera. In extreme conditions, fire in the adsorber and the combustion of activated carbon was achieved during ketone adsorption. Data have been extracted from these experiments, including local temperature, front velocity and carbon bed combustion conditions. [ABSTRACT FROM PUBLISHER]

The presence of pharmaceutical residues in water resources is a critical issue for the production of drinking water, even though trace concentrations are mostly encountered. The adsorption of eight micropollutants, in mixture, onto a microporous activated carbon fibre cloth was investigated. For each compound, the kinetics and isotherms of adsorption were studied in batch reactors with ultrapure water, groundwater and half-diluted groundwater. Experimental data were generated and compared to values calculated by the association of Ideal Adsorbed Solution Theory (IAST) model and the Homogeneous Surface Diffusion Model (HSDM). The impact of the nature and the content of Natural Organic Matter (NOM) was modelled considering an Equivalent Background Compound (EBC). The presence of NOM in the groundwater is largely detrimental for the adsorption of trace micropollutants.

Although there is a growing interest in Fenton oxidation processes based on natural catalysts, the use of laterite soil to promote sequential adsorption/oxidation treatments of fluoroquinolone antibiotics has been scarcely investigated. In this work, the ability of an african laterite containing goethite and hematite to remove flumequine (FLU), used as a representative compound of fluoroquinolone antibiotics, was evaluated under dark and UVA irradiation. Batch experiments and liquid chromatography analyses showed that the presence of laterite can enhance FLU removal from heavily contaminated water through both sorption and oxidation reactions (up to 94% removal of 77 μmol L -1 of FLU and 72% of mineralization). The heterogeneous reaction rate is dominated by the rate of intrinsic surface chemical reactions including sorption and oxidation of FLU, and light-induced reduction of Fe III sites to produce Fe II . Based on the probe and scavenging experiments, OH radicals were mainly involved in the heterogeneous oxidation reaction. The photo-assisted Fenton process showed a high efficiency of FLU removal even in the presence of a second fluoroquinolone antibiotic, norfloxacin (NOR), which can be co-found with FLU in affected environments. Determinations of kinetic rate constants and total organic carbon (TOC) for five sequential adsorption/oxidation cycles showed that laterite exhibited no deactivation of surface sites and an excellent catalytic stability. This cost-effective and environmentally friendly remediation technology may appear as a promising way for the removal of fluoroquinolone antibiotics from multi-contaminated waters., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Three volatile organic compounds (VOCs), benzene, cyclohexane, and dichloromethane, were adsorbed onto activated carbon fiber cloth. 1 H (magic-angle spinning (MAS) and pulsed field gradient (PFG)) NMR techniques were carried out, and the signals were analyzed in terms of peak surface areas and shifts. These techniques were shown to be very useful for determining (i) the intrinsic quantification of adsorbed molecules (VOCs and/or water) in the porosity of the materials (the adsorption capacities ranged from 0.2 to 4 mol·kg -1 ); (ii) the mechanisms of interactions between adsorbed organic molecules and the carbon walls (illustrations of positions of the molecule inside the pore volume are proposed; the proton-wall distance was less than 0.15 nm); and (iii) the diffusivities (surface diffusion coefficients (D S ) were estimated at ≈4.10 -12 m 2 ·s -1 for cyclohexane, ≈1.10 -11 m 2 ·s -1 for benzene, and ≈4.10 -11 m 2 ·s -1 for dichloromethane).

Objective: Dendritic cells (DCs) are critical effectors of innate and adaptive immunity playing crucial roles in autoimmune responses. We previously showed that blood DC numbers were reduced in autoimmune antineutrophil cytoplasmic autoantibody-associated vasculitis (AAV). Here, we assessed toll-like receptor (TLR) responsiveness of blood DCs from patients with granulomatosis with polyangiitis (GPA) or microscopic polyangiitis (MPA)., Methods: Blood samples from healthy controls (HCs), GPA, or MPA patients, without treatment, during acute phase (AP) or remission phase (RP) were analyzed. Cytokine production by DCs and T cells was assessed on whole blood by flow cytometry after TLRs or polyclonal stimulation, respectively., Results: We first showed that GPA and MPA are associated with a decreased blood DC number during AP. Conventional DCs (cDCs) from patients with GPA and MPA in AP exhibited a profound decrease of IL-12/IL-23p40 production after TLR3, 4, or 7/8 stimulation compared to patients in remission and HC, with a return to normal values in RP. TNFα secretion was also affected, with a decrease in cDCs from GPA patients in AP after TLR3 stimulation but an increase after TLR7/8 stimulation. By contrast, the responsiveness of plasmacytoid DCs to TLR7 and 9 was only marginally affected. Finally, we observed that IFNγ-producing CD4 + T cell frequency was significantly lower in AP-GPA patients than in HC., Conclusion: We describe, for the first time, a dysregulated response to TLRs of circulating DCs in AAV patients mostly affecting cDCs that exhibit an unexpected reduced inflammatory cytokine secretion possibly contributing to an altered Th cell response.

Natural organic matter (NOM) is a major water constituent that affects the performance of water treatment processes. Several studies have shown that NOM can be adsorbed on the surface of oxides and may compete with other ions. The overall goal of this study was essentially to investigate the competitive adsorption between fluoride and NOM on activated alumina (AA). For this purpose, a humic acid (HA) was used as a model compound for NOM. The interaction of NOM with fluoride, the simultaneous competitive adsorption, and the effect of preloading AA with NOM were investigated. The specific absorbance of HA was determined at 254 nm. Size-exclusion chromatography measurements confirmed the adsorption of aromatic fractions of NOM onto AA. The presence of HA in the system inhibited fluoride sorption onto AA and the removal yield using fresh AA decreased from 70.4 % to 51.0 % in the presence of HA. The decrease was more pronounced using AA preloaded with HA, reaching 37.7 %. The interference of coexisting ions and their effect on fluoride removal capacity were evaluated, showing a severe impact of the presence of phosphate on the removal capacity unlike nitrates and sulfates, which slightly improved the fluoride sorption.

Activated carbon fiber cloths (ACFC) have shown promising results when applied to water treatment, especially for removing organic micropollutants such as pharmaceutical compounds. Nevertheless, further investigations are required, especially considering trace concentrations, which are found in current water treatment. Until now, most studies have been carried out at relatively high concentrations (mg L(-1)), since the experimental and analytical methodologies are more difficult and more expensive when dealing with lower concentrations (ng L(-1)). Therefore, the objective of this study was to validate an extrapolation procedure from high to low concentrations, for four compounds (Carbamazepine, Diclofenac, Caffeine and Acetaminophen). For this purpose, the reliability of the usual adsorption isotherm models, when extrapolated from high (mg L(-1)) to low concentrations (ng L(-1)), was assessed as well as the influence of numerous error functions. Some isotherm models (Freundlich, Toth) and error functions (RSS, ARE) show weaknesses to be used as an adsorption isotherms at low concentrations. However, from these results, the pairing of the Langmuir-Freundlich isotherm model with Marquardt's percent standard of deviation was evidenced as the best combination model, enabling the extrapolation of adsorption capacities by orders of magnitude., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Gaucher disease (GD) is caused by an autosomal-recessive deficiency of β-glucocerebrosidase leading to an accumulation of glucosylceramide in monocytes/macrophage lineage. We analyzed immune cells and especially the function of dendritic cells to evaluate the potential impact of glucosylceramide accumulation in these cells and its possible role in infections and malignancies usually described in this pathology. These analyses were performed for each patient without and under enzyme replacement therapy., Methods: Seven GD patients were studied and compared with healthy volunteers. Immune cells (B cells, T cells, NK, dendritic cells), were analyzed by flow cytometry directly on whole blood. Cytokine production by blood dendritic cells was assessed after stimulation by toll-like receptor ligands. Cytokines in sera were measured using a multiplex assay., Results: GD patients displayed decreased numbers of NK cells, γδ2 T cells and increased frequency of memory CD4(+)CD45RO(+) T cells, when compared to healthy controls. Numbers of dendritic cells (myeloid (mDC) and plasmacytoid (pDC) dendritic cells) were also decreased. We demonstrated that pDC from GD patients exhibited a decrease in IFNα production after TLR9 stimulation compared to controls. Importantly, enzyme replacement therapy restored pDC function. Finally, we observed an increase of IL-8 and IL-18 in GD patient sera, which were reduced under enzyme replacement therapy., Conclusions: Our data confirm that patients with GD exhibit altered numbers of innate and T lymphocytes and show for the first time that pDC from GD patients exhibit altered responsiveness to TLR9. These alterations could contribute to a decreased response to pathogens and could favor the development of malignancies., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Adsorption of Volatile Organic Compounds (VOCs) is one of the best remediation techniques for controlling industrial air pollution. In this paper, a quantitative predictor model for the characteristic adsorption energy (E) of the Dubinin-Radushkevich (DR) isotherm model has been established with R(2) value of 0.94. A predictor model for characteristic adsorption energy (E) has been established by using Multiple Linear Regression (MLR) analysis in a statistical package MINITAB. The experimental value of characteristic adsorption energy was computed by modeling the isotherm equilibrium data (which contain 120 isotherms involving five VOCs and eight activated carbons at 293, 313, 333, and 353 K) with the Gauss-Newton method in a statistical package R-STAT. The MLR model has been validated with the experimental equilibrium isotherm data points, and it will be implemented in the dynamic adsorption simulation model PROSIM. By implementing this model, it predicts an enormous range of 1200 isotherm equilibrium coefficients of DR model at different temperatures such as 293, 313, 333, and 353K (each isotherm has 10 equilibrium points by changing the concentration) just by a simple MLR characteristic energy model without any experiments., (Copyright © 2012 Elsevier Inc. All rights reserved.)

In this research work, the three different VOCs such as acetone, dichloromethane and ethyl formate (with corresponding families like ketone, halogenated-organic, ester) are recovered by using temperature swing adsorption (TSA) process. The vapors of these selected VOCs are adsorbed on a microporous activated carbon. After adsorption step, they are regenerated under the same operating conditions by hot nitrogen regeneration. In each case of regeneration, Factorial Experimental Design (FED) tool had been used to optimize the temperature, and the superficial velocity of the nitrogen for achieving maximum regeneration efficiency (R(E)) at an optimized operating cost (OP(€)). All the experimental results of adsorption step and hot nitrogen regeneration step had been validated by the simulation model PROSIM. The average error percentage between the simulation and experiment based on the mass of adsorption of dichloromethane was 3.1%. The average error percentages between the simulations and experiments based on the mass of dichloromethane regenerated by nitrogen regeneration were 4.5%., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The regeneration experiments of dichloromethane from activated carbon bed had been carried out by both hot nitrogen and steam to evaluate the regeneration performance and the operating cost of the regeneration step. Factorial Experimental Design (FED) tool had been implemented to optimize the temperature of nitrogen and the superficial velocity of the nitrogen to achieve maximum regeneration at an optimized operating cost. All the experimental results of adsorption step, hot nitrogen and steam regeneration step had been validated by the simulation model PROSIM. The average error percentage between the simulation and experiment based on the mass of adsorption of dichloromethane was 2.6%. The average error percentages between the simulations and experiments based on the mass of dichloromethane regenerated by nitrogen regeneration and steam regeneration were 3 and 12%, respectively. From the experiments, it had been shown that both the hot nitrogen and steam regeneration had regenerated 84% of dichloromethane. But the choice of hot nitrogen or steam regeneration depends on the regeneration time, operating costs, and purity of dichloromethane regenerated. A thorough investigation had been made about the advantages and limitations of both the hot nitrogen and steam regeneration of dichloromethane., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Organic vapors emitted from solvents used in chemical and pharmaceutical processes, or from hydrocarbon fuel storage stations at oil terminals, can be efficiently captured by adsorption onto activated carbon beds. To recover vapors after the adsorption step, two modes of regeneration were selected and could be possibly combined: thermal desorption by hot nitrogen flow and vacuum depressurization (VTSA). Because of ignition risks, the conditions in which the beds operate during the adsorption and regeneration steps need to be strictly controlled, as well as optimized to maintain good performances. In this work, the optimal conditions to be applied during the desorption step were determined from factorial experimental design (FED), and validated from the process simulation results. The regeneration performances were compared in terms of bed regeneration rate, concentration of recovered volatile organic compounds (VOC) and operating costs. As an example, this methodology was applied in case of dichloromethane. It has been shown that the combination of thermal and vacuum regeneration allows reaching 82% recovery of dichloromethane. Moreover, the vacuum desorption ended up in cooling the activated carbon bed from 93°C to 63°C and so that it significantly reduces the cooling time before starting a new cycle., (Copyright © 2011 Elsevier B.V. All rights reserved.)

A theoretical model was built to simulate the adsorption of volatile organic compounds (VOCs) onto activated carbons in a fixed bed. This model was validated on a set of experimental data obtained for the adsorption of acetone, ethyl formate, and dichloromethane onto five commercial activated carbons. The influence of operating conditions was modeled with various VOC contents atthe inlet of the adsorber and superficial velocities of the gas-phase from 0.14 to 0.28 m.s(-1). Breakthrough times and maximum temperature rises were computed with a coefficient of determination of 0.988 and 0.901, respectively. The simulation was then extended to the adsorption of mixtures of VOCs. From the comparison of simulation and experimental results, the advantage of accounting for dispersions of heat and mass is shown and the importance in taking into account the temperature effect on the equilibrium data is demonstrated.

Background: The French has been insufficiently characterized so far for mitochondrial DNA (mtDNA) diversity., Aims: The study aimed to enhance the information available for the French mtDNA pool and to explore the potential microgeographical differentiation of two French regions selected for their linguistic and historical idiosyncrasies., Subjects and Methods: A total of 868 samples from 12 different locations in France were collected. They were sequenced for the hypervariable segment I (HVS-I) and typed for haplogroup defining markers from the coding region either by restriction fragment length polymorphism (RFLP) or by a new protocol based on the 5' nuclease allelic discrimination. The mtDNA gene pools of French Basques and Bretons were compared in terms of frequency and composition with relevant neighbouring populations., Results: The French Basques' mtDNA pool shares some common features with that of the Spanish Basques, such as the high frequency of haplogroup H. However, the French Basques exhibit a number of distinct features, most notably expressed in the prevalence of haplogroups linked with the Neolithic diffusion in Europe. In Brittany, Finistère shows closer affinities with Britain and Scandinavia than the two other departments of Brittany., Conclusion: The mtDNA haplogroup composition of the French does not differ significantly from the surrounding European genetic landscape. At a finer grain, microgeographical differentiation can be revealed, as shown for the French Basque country and for Brittany.

New series of 2(or 3)-arylmethylenenaphtho[2,1-b]furan-3(or 2)-ones were synthesized, characterized and tested for anticancer properties in vitro. The target compounds were prepared by Knoevenagel coupling between the naphthofuranones 3, 28-30 and formyl derivatives. 2-(4-Oxo-1-benzopyran-3-ylmethylene)naphtho[2,1-b]furan-3-one 36 was the most active compound (IC50 (L1210) = 1.6 microM). These compounds were also evaluated, in an independent manner, as inhibitors of Src protein tyrosine kinase, but only minor activity was observed.

Several new pyridazino[1',6':1,2]pyrido[3,4-b]indol-5-inium derivatives were synthesised from beta-carboline derivatives and their cytotoxic activity and effect on the cell cycle were evaluated against L1210 cancer cells.

We have characterized the human gene SLC39A4, which encodes a protein with features characteristic of a ZIP zinc transporter. The chromosomal location and expression of SLC39A4, together with mutational analysis of eight families affected with acrodermatitis enteropathica, suggest that SLC39A4 is centrally involved in the pathogenesis of this condition.