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Electric-assisted capillary rise adsorption of polar and nonpolar solvents by cellulose and chitosan was studied by employing an electrostatic generator to assist a common capillary rise wetting by taking the anode and cathode electrodes respectively linked to a metal tube charged with samples and the probe solvent. To vary the voltage at 0, 100, 200, and 300 V, respectively, the recorded dynamic adsorption results showed that the cellulose and chitosan both kept a stable adsorption of the nonpolar hexane and diiodomethane, obviously ignoring the voltage increase. Moreover, the hexane amount adsorbed by cellulose and chitosan is similar, while the diiodomethane amount was adsorbed to a greater amount by cellulose as compared with the chitosan corresponding to these two biomaterials-based nonpolar components, for example, greater for cellulose and smaller for chitosan. Results also showed that the adsorption of polar water and formamide was gradually increased with the voltage increase, especially for chitosan, to correspond to the polar component of these materials, for example, greater for chitosan and smaller for cellulose. These adsorption behaviors suggested that the application of an extra electric field can only enhance the adsorption of polar solvent, and the molecular structure, for exmaple, the β-(1-4)-linked d-glucosamine units of chitosan, has sensitive electric field responses in polar solvent adsorption as compared with those of the β(1-4)-linked d-glucose units of cellulose. The reason for the electric adsorption behaviors was known due to the presence of an extra electric-field-induced reduction of the total surface tension of solvent and mainly the polar component. [ABSTRACT FROM AUTHOR]

Background: Few useful patient-reported outcomes scales for functional dyspepsia exist in China. Aims: The purpose of this work was to translate and cross-culturally adapt the Functional Digestive Disorders Quality of Life Questionnaire (FDDQL) from the English version to Chinese (in Mandarin). Methods: The following steps were performed: forward translations, synthesis of the translations, backward translations, pre-testing and field testing of FDDQL. Reliability, validity, responsiveness, confirmatory factor analysis, item response theory and differential item functioning of the scale were analyzed. Results: A total of 300 functional dyspepsia patients and 100 healthy people were included. The total Cronbach's alpha was 0.932, and split-half reliability coefficient was 0.823 with all test-retest coefficients greater than 0.9 except Coping With Disease domain. In construct validity analysis, every item correlated higher with its own domain than others. The comparative fit index of FDDQL was 0.902 and root mean square error of approximation was 0.076. Functional dyspepsia patients and healthy people had significant differences in all domains. After treatment, all domains had significant improvements except diet. Item response theory analysis showed the Person separation index of 0.920 and the threshold estimator of items was normally distributed with a mean of 0 and standard deviation of 1.27. The residuals of each item were between −2.5 and 2.5, without statistical significance. Differential item functioning analysis found that items had neither uniform nor non-uniform differential item functioning in different genders and age groups. Conclusions: The Chinese version of FDDQL has good psychometric properties and is suitable for measuring the health status of Chinese patients with functional dyspepsia. [ABSTRACT FROM AUTHOR]