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In this work, the solubilities of carbamazepine (CBZ) (form III) in ethyl acetate, methyl acetate, ethylene glycol, chloroform and cyclohexylamine were determined by laser monitoring techniques at pressure above sea level, and the solubility data of CBZ (form III) in different pure solvents were fitted by the Modified Apelblat model and λh model. The result shows that the solubility of CBZ (form III) in five solvents increases as temperature rises, and the solubility in chloroform was the largest. The experimental solubility values of CBZ (form III) in ethyl acetate, methyl acetate, chloroform and cyclohexylamine were in better agreement with the simulated fitting values of the λh model. For ethylene glycol, the σ value was much larger than the other four solvents, and it can be seen from the λh model that ethylene glycol was closer to the ideal solution system than the other four solvents.

Nonsense-mediated mRNA decay (NMD) is a highly conserved regulatory mechanism of post-transcriptional gene expression in eukaryotic cells. NMD plays essential roles in mRNA quality and quantity control, and thus safeguards multiple biological processes including embryonic stem cell differentiation and organogenesis. UPF3A and UPF3B in vertebrate species, originated from a singleUPF3gene in yeast, are key factors in the NMD machinery. While UPF3B is a well-recognized weak NMD-promoting factor, whether UPF3A functions in promoting or suppressing NMD is under debate. In this study, we generated aUpf3aconditional knockout mouse strain, and established multiple lines of embryonic stem cells and somatic cells without UPF3A. Through extensive analysis on the expressions of 33 NMD targets, we found UPF3A neither represses NMD in mouse embryonic stem cells, somatic cells, nor in major organs including the liver, spleen, and thymus. Our study reinforces that UPF3A is dispensable for NMD when UPF3B is present. Furthermore, UPF3A may weakly and selectively promote NMD in certain murine organs.Summary blurbWe generated a newUpf3ainducible knockout mouse model and showed that UPF3A does not repress expressions of NMD target genes in embryonic stem cells, somatic fibroblasts, as well as multiple tissues from adult mice.

A new type of water-retaining, slow-release fertilizer (WSF) based on double-network hydrogels was fabricated via the ion-crosslinking of sodium carboxymethyl cellulose and the free radical polymerization of polymerizable β-cyclodextrin (MAH-CD), polyethylene glycol dimethacrylate (PEGDA), acrylamide (AM), and acrylic acid (AA) with urea-loaded halloysite as an additive. The effects of the AM to AA monomer ratio, the halloysite content, the AlCl3 content and the MAH-CD content on the swelling ratio were studied. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA) were applied to characterize the structure and properties of the WSF. The swelling behavior and water retention capacity of the fertilizer were investigated using a classic gravimetric method. The experimental results indicated that the presence of halloysite nanotubes clearly adjusted the swelling and release properties of the WSF. Kinetic modeling indicated that the swelling mechanism and slow release behavior were consistent with a Fickian diffusion mechanism. Form the considerations of its properties and raw materials, the fertilizer developed here has a good prospect of application and extension.

In this work, novel sodium alginate-based double-network hydrogel beads were prepared and applied for the water-retention and slow release of fertilizers (WSF). The WSF beads were prepared by ion-crosslinking and the free radical polymerization of acrylic acid, acrylamide, and polymerizable β-cyclodextrin in the presence of urea-loaded halloysites. The WSF beads were characterized using SEM, FTIR, and TGA. Their swelling capacity and water retention were measured by a weighing method and their slow-release behavior was studied by spectrophotometry. The water retention and slow release results showed that the fertilizer displayed improved urea release and water retention properties, indicating that halloysite nanotubes clearly improved the performance of fertilizers. In addition, the experimental data of the slow release of urea in water and soil better fitted the Korsmeyer-Peppas model compared with the Higuchi model, a zero-order model or a first order mode. The release behavior of the fertilizer beads followed a Fickian diffusion mechanism.

In this work, ternary phase diagrams of telmisartan-saccharin (TEL-SAC) cocrystal in methanol, ethanol, and quasi-ternary sections of the quaternary system TEL-SAC–chloroform–methanol were determin...

In this work, solubility of exo-3,6-epoxy-1,2,3,6-tetrahydrophthalic anhydride (ETA) was measured and discussed in acetone + ethanol, methyl acetate + ethanol, 1,4-dioxane + ethanol, and ethyl acet...

The solid–liquid phase equilibrium solubility of doxycycline hyclate (DH) in 10 pure organic solvents and cosolvent mixtures DMF (1) + ethanol (2), DMSO (1) + ethanol (2) and acetone (1) + ethanol ...

The solid-liquid phase equilibrium solubility of Doxofylline was measured and discussed in ten pure organic solvents and co-solvent mixtures of acetonitrile + ethanol (+or water) at temperature range from 278.15 to 323.15 K. Results indicated that experimental mole fraction (x) of Doxofylline in ten neat solvents followed this order: acetonitrile > tetrahydrofuran > benzene > acetone > ethyl acetate > methanol > 1-propanol ≈ 2-propanol > ethanol ≈ water, and solubility increased with temperature increasing. Moreover, experimental solubility of Doxofylline firstly increased and then declined with the mass fraction increasing of acetonitrile in acetonitrile + ethanol (+or water) mixture solvents at each temperature. Hansen solubility parameter and solvent effect were used for explaining and discussing solubility rule of Doxofylline in selected solvents. Model correlation indicated the NRTL model was the most suitable than other models to predict solubility of Doxofylline in pure solvents and Sun model was better than other models in mixture solvents with accompanied by temperature and composition. Furthermore, thermodynamic properties of standard molar enthalpy, molar Gibbs free energy and molar entropy in solution was calculated and discussed.

The solubility data of tylosin tartrate in methanol + (tetrahydrofuran or acetone) mixtures was determined at atmospheric pressure by a gravimetric method over temperature range of 293.15–323.15 K. The experimental results indicated that solubility of tylosin tartrate increases with increasing temperature in selected solvents, and that solubility of tylosin tartrate first increases, reaches a maximum and then decreases with increasing the mass fraction of methanol in the binary solvent mixtures at constant temperature. Solubility data were correlated by Apelblat model and λh model, the results showed that the two models agreed well with the experimental data, and the λh model is a little more accurate than Apelblat model from R2 and the total root-mean-square deviations (RMSD). The molar enthalpy (△ Ho) and entropy (△ So) for tylosin tartrate dissolution in solvent mixtures were calculated with solubility data using van't Hoff equation, dissolution process of tylosin tartrate was endothermic process, △ Ho > 0 and was an entropy-drives process △ So > 0. Therefore, the experimental data and model parameters would provide essential support for industrial design and further theoretical studies.

Data on (solid + liquid) equilibrium of tylosin tartrate in {methanol + (ethanol, 1-propanol or 2-propanol)} solvents will provide essential support for industrial design and further theoretical studies. In this study, the solubility of tylosin tartrate in alcohol mixtures was measured over temperature range from (278.15 to 323.15) K under atmospheric pressure by a gravimetric method. From the experimental results, the solubility of tylosin tartrate in selected solvents noted above was found to increase with increasing temperature and mass fraction of methanol. The solubility data were correlated with the modified Apelblat equation, the λh equation and van’t Hoff equation. The results showed that the three equations agreed well with the experimental values, and that the modified Apelblat equation was more accurate than the λh equation and van’t Hoff equation. Further, the standard enthalpy, standard entropy and standard Gibbs free energy of solution of tylosin tartrate in mixed solvents were calculated according to solubility results, model parameters with modified Apelblat equation and van’t Hoff equation.

The synthesis of D-isoascorbyl stearate from D-isoascorbic acid and stearic acid with immobilized lipase (Novozym(®)435) as catalyst was studied. Response surface methodology and Box-Behnken design with six variables and three levels were employed to evaluate the effects of processing conditions on the conversion of D-isoascorbic acid. The results confirmed that the response surface method and statistical analysis were proved to be useful in developing optimal conditions for D-isoascorbyl stearate synthesis. The optimum conditions were predicted as follows: reaction temperature 48 °C, reaction time 17.7 h, immobilized lipase amount 50.0 % (w/w, of D-isoascorbic acid), substrate molar ratio 9:1 (stearic acid to D-isoascorbic acid), D-isoascorbic acid concentration 0.14 mol/L (based on solvent), 4A molecular sieve addition 200 g/L (based on solvent), and the optimal conversion was 90.6 %. Through the kinetics model fitting of the esterification, it was considered that the esterification conformed to a Ping-Pong bi-bi kinetic model with D-isoascorbic acid inhibition, and the obtained kinetic constants showed that the inhibition of D-isoascorbic acid and the enzyme affinity to substrate were abate with the increase of the reaction temperature.

The solubility values of Doxycycline Hyclate (DH) in water + methanol (or +ethanol and n-propanol) mixture solvents were measured and correlated from 276.95 K to 323.75 K. Experiment results indicated that solubility data in four pure solvents followed this order: methanol> ethanol≈water>n-propanol, and solubility data increased with increasing temperature in all selected solvents. In mixture solvents, the solubility data of Doxycycline Hyclate reached a minimum at xc = 0.75 in water(xc) + methanol(1-xc), a maximum at xc = 0.75 in water(xc) + ethanol(1-xc) and a maximum at xc = 0.8 in water(xc) + n-propanol(1-xc). Moreover, Experimental solubility data was well-correlated with the modified Apelblat model, the Apelblat-Jouyban Acree model and Van't Hoff-Jouyban Acree model, respectively. Correlation coefficient values and relative average deviation values showed these models were very consistent with the experimental values. Furthermore, thermodynamic properties of Doxycycline Hyclate in dissolution process were calculated and discussed from the experimental solubility and parameters of modified Apelblat model.

In China, water fluoridation was begun in Guangdong province in Guangzhou in 1965 and in Dongguan in 1974, and was stopped in 1983 and 1986, respectively. There is at present no fluoridation being practiced in China. Both cities are located north of Hong Kong and belong to the subtropical zone (mean temperature=71.1°F). According to Minoguchi's formula, an optimal fluoride concentration is 0.6-0.7ppm. The fluoride concentration was unstable for the first 10 years, when annual fluoride concentrations ranged from 0.8ppm to 0.9ppm, higher than the optimal fluoride concentration. After that the concentration was about 0.7ppm. The fluoride concentration of drinking water in Guangzhou may have been sometimes higher than the optimal fluoride concentration. In December 1990, seven years after fluoridation was discontinued, a dental survey of schoolchildren aged 15 was made in Guangzhou, and also in Fushan (0.2ppm) as a control area. Two dentists examined dental caries and one dentist examined dental fluorosis with Dean's Index, and other enamel defects were also recorded. Subjects were 62 students in Guangzhou and 71 students in Fushan. The mean DMFT was 0.44 (SE=0.10) in Guangzhou and 2.20 (0.33) in Fushan. The percent difference was 80% (p