How Do Mobile Social Apps Matter for College Students' Satisfaction in Group-Based Learning? The Mediation of Collaborative Learning.

Recently, many universities apply mobile tools to teaching practices. For instance, some teachers may set up groups on mobile social apps and assign course tasks and advise college students to submit papers online. Nevertheless, how these mobile social apps affect teaching practices, especially the process of students' satisfaction needs to be further explored. To fill this research gap, we build a theoretical model of how mobile social apps' functions affect course satisfaction from the perspective of Media Richness theory and the Uses and Gratifications (U and G) theory. A total of 186 valid questionnaires from college students in China were collected, and a structural equation model was built to test our research model. The results show that as: (1) only the communication function has positive impacts on knowledge sharing, while the impact of the information storing function and information distribution function on knowledge sharing is not significant; (2) knowledge sharing does not affect course satisfaction in a direct way, but it can act indirectly through promoting collaborative learning, which shows the mediating role of collaborative learning. The theoretical implications and practical implications of the study are discussed.

Comprehensive studies on the nature of interaction between carboxylated multi-walled carbon nanotubes and bovine serum albumin.

Herein, the interaction between carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) and bovine serum albumin has been investigated by using circular dichroism, UV-vis, and fluorescence spectroscopic methods and molecular modeling in order to better understand the basic behavior of carbon nanotubes in biological systems. The spectral results showed that MWCNTs-COOH bound to BSA and induced the relatively large changes in secondary structure of protein by mainly hydrophobic forces and π-π stacking interactions. Thermal denaturation of BSA in the presence of MWCNTs-COOH indicated that carbon nanotubes acted as a structure destabilizer for BSA. In addition, the putative binding site of MWCNTs-COOH on BSA was near to domain II. With regard to human health, the present study could provide a better understanding of the biological properties, cytotocicity of surface modified carbon nanotubes.

The Primary Research on the Gut Microbes in KKAy Mice.

In the first part of this paper, gut microbial difference of two genotypes mice was researched. The gut microbial community of type 2 diabetes animal model KKAy mice and normal C57BL/6J mice had clear distinctions in DGGE (denaturing gradient gel electrophoresis) profiles. The pairwise similarity coefficient (C s ) was only 26-44 % between KKAy and C57BL/6J, but C s was 82-100 % among same genotypes mice. Thirteen dominant bands were cloned from DGGE profiles to exhibit difference on gut microbial structure further. In the second part of this paper, the influence of hypoglycemic drug Pioglitazone on the gut microbes in KKAy mice was researched by gut microbial diversity analysis and principal component analysis (PCA). The results showed that Pioglitazone reduced the gut microbial diversity slightly and changed gut microbial structure of KKAy mice to that of normal C57BL/6J mice.