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Bromothymol blue (BTB) pH indicator was encapsulated into polysiloxane network using the sol-gel process. Transparent monolithic disks of entrapped BTB were obtained in the presence of cetyl trimethyl ammonium bromide (CTAB) or dodecyl dimethyl amino oxide (Genaminox LA, GLA) surfactant. Ultraviolet visible spectra showed that the encapsulated BTB retains its structure in terms of its response to pH. The kinetic studies reveal that there was a faster response to pH in the case of GLA surfactant than in the case of CTAB. It is found that the co-entrapment of cationic surfactant CTAB or zwitterionic surfactant GLA with TEOS has shifted the equilibrium of the BTB to the ionized form due to the electrostatic interaction between the surfactant and the BTB anion and therefore the base form becomes more pronounced (e.g., shift from yellow to red) than that of sol-gel matrix without surfactant.

Phenol red was immobilised into a polysiloxane matrix using a sol-gel process to form pH optical sensors. The sol-gel was obtained by hydrolysis of tetraethoxysilane (TEOS) in the presence of phenol red (PR) and the appropriate surfactant. Different surfactants, namely cetyltrimethylammonium bromide (CTAB), dodecyldimetyl amino-oxide (GLA) and Triton X-100 (TX-100), were employed. Interestingly, the use of surfactants significantly improved the mesostructure of the silica and increased the porosity of the system. The two response pH ranges were shifted to pH 0.0–3.0 and pH 10.5–1.5M [OH−] compared with those of the free PR (pH 0.0–3.0 and pH 6.5–9.5). It is found that the pH response and the pKa shift of the phenol red were dependent, not only on the silica matrix but also on the ionic properties of surfactants. In the case of ionic surfactants such as CTAB or GLA, there was further shift to more acidic and more basic pH, whereas in the case of non-ionic surfactants such as TX-100 no significant change of...

Lead/lead oxide Pb/PbO2 modified electrodes was prepared for electrocatalytic oxidation of agrochemicals including herbicidal 2,4-D (albar super) and pure 2,4-dichlorophenoxy acetic acid. The results of electrocatalytic oxidation process of the agrochemical solutions were expressed in terms of the remaining concentration and COD removal. The different operating conditions of treatment process were investigated including current density, pH, temperature, time of electrolysis, type of conductive electrolyte, and its specific conductance. This electrode gives good results for the removal of agrochemicals and COD. Also, the results showed the best conductive electrolytes is NaCl. This observation was attributed to the small size of Na+ and contribution of Cl− ion in formation of OCl−.

Encapsulation of bromothymol blue (BTB) into a polysiloxane network was prepared using sol-gel method without using a catalyst. The co-entrappment of the bromothymol blue (BTB) and surfactant cetyltrimethyl ammonium bromide (CTAB) was used to modify the properties of the sol-gel matrixes which may provide a highly porous materials and made the polysiloxane network an excellent host for sensing molecules. Monolithic disks of trapped BTB were obtained with no leaching. Polarized light microscopy shows that a almost unique particle sizes distributions were formed. The immobilized BTB shows a response for various pH solutions, the feature of absorption spectra of the immobilized BTB was almost the same as that of the solutions.

In a pot experiment, oil cakes of cotton, flax, olive, sesame and soybean were mixed with soil at the rate of 5, 10, 15, 20 or 50 g/kg soil. We compared their nematicidal potential with carbofuran as a standard against the root-knot nematode, Meloidogyne incognita infecting tomato. Their effects on the growth parameters of tomato plants were also investigated. The results showed that M. incognita populations in the soil and root galling were significantly suppressed when the tested cakes, at all rates, were allowed to decompose in the soil. All oil cakes exhibited varying degrees of reduction compared to the control. The highest reduction in galls was noted in plants treated with sesame cake, whereas the lowest reduction was observed in plants treated with olive cake. On the other hand, the highest reduction in J2 was noticeable in the plants grown in olive-cake-amended soil followed by sesame, soybean, cotton and flax cake. In addition, employing a high rate of the tested cakes gave higher activ...

The aim of the present study was to formulate six different plant seed oils namely canola, cotton, flax, olive, sesame and soybean as emulsifiable concentrates. The composition of the formulation comprises at least one organic solvent, one surfactant and one plant oil. Physico-chemical properties of the formulated oils (emulsion stability test, cold stability and heat stability tests) were measured. The successfully emulsified oils were evaluated for nematicidal activity against Meloidogyne incognita infecting tomato plants under greenhouse conditions. Emulsified canola oil proved to be the most effective oil as a protectant against M. incognita infection to tomatoes followed by soybean, cotton, flax and sesame oil. In addition, employing a high rate of the tested emulsified oils gave higher activity in suppressing nematodes both in the soil and in tomato roots than using a low rate. Moreover, all tested formulated oils at both rates of application had no adverse effect on the growth of tomato pl...

The preparation of transparent monolithic silica doping with Alizarin Red S was carried out by acid catalyzed sol–gel reaction of tetraethylorthosilicate (TEOS) in the presence of Alizarin Red S. The immobilized Alizarin Red S pH indicator shows similar behavior as its solution counterpart. The UV/VIS spectra indicate that the Alizarin Red S retains its structure during the sol–gel reactions in terms of response to pH. Therefore, the Alizarin Red S can be regarded as uniformly distributed in the sol–gel matrix. Also, addition of the dye plus SDS into the sol–gel matrix modifies the structure of the net work and makes it more homogeneous and increases the surface area. These characteristics were justified by using polarized microscope technique.

This research involves the behavior of thymol phtalein pH indicator entrapped into the sol‐gel derived inorganic matrix. The method is based on the physical entrapment of the reagent molecules in the sol‐gel matrix. The immobilized thymol phthalein pH indicator shows behavior similar to its solution counterpart. The UV/vis spectra indicate that the thymol phthalein retains its structure during the sol‐gel reactions in terms of response to pH. Thymol phthalein can be regarded as uniformly distributed in the sol‐gel matrix. This observation has been confirmed using polarized microscopy. This research shows that thymol phtalein can be immobilized in sol‐gel glasses and used as a solid pH sensor.

This research reports on the oxidation of different amines such as dibutylamine, diethylamine, dipropylamine, ethylamine, ethylmethylamine, propylamine, triethylamine, and trimethylamine by 0.001 M potassium ferricyanide in the presence of 0.03 M NaOH at 25°C in aqueous medium and/or in 0.03 M N,N-dimethyldodecylamine N-oxide (DDAO). Oxidation rates were studied with a spectrophotometer at 420 nm. The experimental data showed that the reaction was first-order with respect to [amine]T and [Fe(CN)6]3−. Also, the rate constant (kobs) had values within the concentration range of 0.015–0.05 M of NaOH and increased above the critical micelle concentration values of DDAO. The dependence of the reaction rate on the nature of the salt was also investigated, and the thermodynamic parameters ΔG*, ΔH*, and ΔS* were calculated. A pseudo-phase model was applied to the system, and the binding constant of the amine to DDAO micelles was calculated.

The phase diagram for the Genaminox 1216 (a zwitterionic surfactant), pentanol‐water system has been constructed at 25°C. The sequence of the phases varies from L1, L1*/Lα, Lα, two phases and L2 as the system was made more lipophilic. Identification of the phases was done by means of crossed polarizer, electrical conductivity and optical polarizing microscopy techniques. Through surface tension measurements, a critical micelle concentration (CMC) of 9 × 10−4 M for the surfactant in aqueous solution was determined. Aromatic salts (such as sodium salicylate and sodium benzoate) reduce the value of this CMC more than aliphatic salts (a sodium citrate and sodium oxalate).This behavior indicates that aromatic salts promote the surfactant assembly more than aliphatic salts. Methyl orange (MO) was used as a solvatochromic reporter to study the nature of interaction of additives with the surfactant by using a UV‐vis technique. The λmax absorption band for aqueous MO has a peak at 463 nm. A blue shift in ...

The kinetic and catalytic oxidation of dibutylamine(DBA), diethyl‐amine(DEA), dipropylamine(DPA), ethylamine(EA), ethylmethylamine(EMA), propylamine (PA), triethylamine(TEA), and trimethylamine(TMA) by 0.001 M potassium ferricyanide in the presence of 0.03 M NaOH at 25°C in aqueous and/or in and 0.003 M sodium dioctylsulfosuccinate (AOT) have been studied using visible spectrophotometry at 420 nm. The present data show that the reaction is first‐order with respect to [amine]T and [Fe(CN)6]3−. Also, the k obs have constant values over 0.015–0.05 M NaOH and decrease below the CMC (of AOT) and increase above the CMC. The characteristics of reaction have been studied in the presence of different salts with common cation or anion. It was observed that in aqueous solution, the k obs values increase with increasing salt concentration for both (0.005–0.06 M) common cation and (0.1–0.6 M) for common anion. But in the presence of AOT, values of k obs initially decrease up to 0.015 M for both types of salts...

Heterogeneity within the self-renewal durability of adult hematopoietic stem cells (HSCs) challenges our understanding of the molecular framework underlying HSC function. Gene expression studies have been hampered by the presence of multiple HSC subtypes and contaminating non-HSCs in bulk HSC populations. To gain deeper insight into the gene expression program of murine HSCs, we combined single-cell functional assays with flow cytometric index sorting and single-cell gene expression assays. Through bioinformatic integration of these datasets, we designed an unbiased sorting strategy that separates non-HSCs away from HSCs, and single-cell transplantation experiments using the enriched population were combined with RNA-seq data to identifykey molecules that associate with long-term durable self-renewal, producing a single-cell molecular dataset that is linked to functional stem cell activity. Finally, we demonstrated the broader applicability of this approach for linking key molecules with defined cellular functions in another stem cell system.

Two segatane diterpenoids containing a bicyclic [4,3,1] ring system were isolated, together with 11 known diterpenoids, four segetanes, five jatrophanes and two paralianes, from the aerial parts of Euphorbia paralias. The structures of the new compounds were established by spectroscopic means, including by 2D NMR and CD spectroscopic analyses. The antifeedant and antiviral activities of the isolated compounds are also described.

The ternary phase diagrams of zwitterionic single-chain hydrocarbon surfactant (tetradecyldimethylaminoxide, C14DMAO)—a perfluoro cosurfactant (1,1-H-dihydroperfluorooctanol, C7F15CH2OH)-H2O, and C14DMAO-C7F15CH2OH-H2O-HCl have been studied at 25°C. The identification of the phases was done by means of electrical conductivity, optical polarizing microscopy, and 2H-NMR techniques. In this system the originally uncharged zwitterionic surfactant was increasingly charged by protonation through addition of HCl. The sequence of the phases observed is similar to that observed for hydrocarbon surfactant–cosurfactant mixtures, namely, L1, L1/Lα, Lα and L2, as relative volume fraction of apolar compound increases over that of polar compound. The absence of sponge phase (L3) is a result of the high bending constant of the mixed bilayers in this perfluoro system.

The ternary phase diagram of dodecyl dimethyl amino oxide (C12DMAO) perfluorooctanol (C7F15CH2OH) – H2O, sodium dodecyl sulfate (SDS) – (C7F15CH2OH) – H20, C12DMAO/SDS (66/33, w/w) – (C7F15CH2OH) – H20, and C12DMAO/SDS (33/66, w/w) – (C7F15CH2OH) – H20 systems have been studied. The identification of the phases was done by macroscopic observation of the sample either by naked eye or through crossed polarizers. For further characterization of the phases, different techniques were used such as electrical conductivity, polarization microscopy, 2H-NMR, and small angle X-ray scattering. The microstructure resulting from the self assembly of the surfactant can vary from normal micelle (L1), lamlar liquid crystal (Lα), to reverse micelles (L2), as relative volume fraction of apolar component increases over that of polar component.

Humans chronically infected with schistosomiasis usually have impaired parasite Ag-specific lymphocyte proliferation and IFN-gamma production that may facilitate persistence of the parasite while producing little clinical disease. The mechanisms that contribute to the immunologic hyporesponsiveness in these patients remain undefined. IL-10 has been shown to exert an inhibitory effect on cell-mediated immunity. To determine whether endogenous IL-10 has a role in regulating parasite-specific anergy in schistosomiasis, neutralizing anti-IL-10 added to PBMC from Schistosoma haematobium patients' enhanced adult worm (SWAP)- or egg Ag (SEA)-driven lymphocyte proliferation and/or IFN-gamma production by 2- to >100-fold in 32 of 38 subjects. In contrast, anti-IL-10 failed to significantly augment the mycobacterial Ag, purified protein derivative (PPD)-driven lymphocyte proliferation, or IFN-gamma production in 9 or 10 of 14 individuals, respectively. SWAP or SEA triggered IL-10 release from PBMC of both patients and healthy individuals; however, CD4+ cells were a significant source of IL-10 only in infected subjects. PPD relative to SWAP induced fivefold less IL-10 release by CD4+ cells (p < 0.01). A possible mechanism whereby IL-10 suppressed Ag-specific T cell responses was demonstrated by the ability of SWAP and not PPD to suppress B7 expression on PBMC. Anti-IL-10 completely inhibited the parasite Ag-induced down-regulation of B7 expression. These studies indicate that IL-10 contributes to parasite Ag-induced T cell hyporesponsiveness observed in patients with chronic schistosomiasis hematobia.

International audience; Zinc oxide nanoparticles were prepared and subsequently deposited onto the surface of the cotton fiber by ultrasonic irradiation. The optical, structure and morphology of the coated and un-coated cotton were examined by UV, fourier transform infrared spectroscopy, X-ray diffraction analysis (XRD) and scanning electron microscope (SEM)/Energy Dispersive X-ray analysis. XRD analysis revealed the presence of the crystalline metal oxide of hexagonal phase with an average crystallite size of 12 nm. These nanoparticles are probably physically adsorbed onto the cotton fiber surface. SEM analysis showed a distribution of ZnO nanorod assemblies of various diameters and lengths physically adsorbed onto the cotton fiber surface may take place. The ZnO-cotton fiber nano-composite were tested against Escherichia coli (gram negative) and Staphylococcus aureus (gram positive) cultures, and showed a significant antimicrobial activity.