Determinants of Information Technology Usage Habit

Habit has been investigated as an antecedent of the information systems usage in a few literatures recent years. But little effort has been found on the determinants of habit itself in the information systems research. Drawing upon the insights from goal-directed behavior, habit/automaticity perspective, and IS continuance model, this paper proposes a research model for understanding the antecedents of the individual information technology usage habit. This study suggest that individual satisfaction, perceived enjoyment and user experience positively influence the strength of usage habit, and that perceived usefulness, confirmation of expectation and perceived enjoyment positively affect satisfaction. The implications are discussed, and contributions of this study are presented

Product Integration Formats and Consumers’ Evaluations of the Online Extended Product: a Product Integration Perspective

After launching new products, firms are spending substantial amount of resources into cross-product integration to attract traffic. While customers place increasing value on product integration, little is known about the influence of product integration on consumers’ evaluation of extended product. Based on the product presentation perspective, this study proposed and validated a research model through a scenario-based experiment. The findings suggest that value added integration, rather than the data interface and add-on module integration, is associated with a higher level of perceived diagnosticity. Perceived diagnosticity had a significant influence on consumers’ evaluations of the extended product. This study contributes to the research and practice by providing insights about product promotion within the online context

Prediction of histone deacetylase inhibition by triazole compounds based on artificial intelligence

A quantitative structure-activity relationship (QSAR) study was conducted to predict the anti-colon cancer and HDAC inhibition of triazole-containing compounds. Four descriptors were selected from 579 descriptors which have the most obvious effect on the inhibition of histone deacetylase (HDAC). Four QSAR models were constructed using heuristic algorithm (HM), random forest (RF), radial basis kernel function support vector machine (RBF-SVM) and support vector machine optimized by particle swarm optimization (PSO-SVM). Furthermore, the robustness of four QSAR models were verified by K-fold cross-validation method, which was described by Q2. In addition, the R2 of the four models are greater than 0.8, which indicates that the four descriptors selected are reasonable. Among the four models, model based on PSO-SVM method has the best prediction ability and robustness with R2 of 0.954, root mean squared error (RMSE) of 0.019 and Q2 of 0.916 for the training set and R2 of 0.965, RMSE of 0.017 and Q2 of 0.907 for the test set. In this study, four key descriptors were discovered, which will help to screen effective new anti-colon cancer drugs in the future

Structure, phosphorylation and U2AF65 binding of the N-terminal domain of splicing factor 1 during 3′-splice site recognition

Recognition of the 3′-splice site is a key step in pre-mRNA splicing and accomplished by a dynamic complex comprising splicing factor 1 (SF1) and the U2 snRNP auxiliary factor 65-kDa subunit (U2AF65). Both proteins mediate protein-protein and protein-RNA interactions for cooperative RNA-binding during spliceosome assembly. Here, we report the solution structure of a novel helix-hairpin domain in the N-terminal region of SF1 (SF1NTD). The nuclear magnetic resonance- and small-angle X-ray scattering-derived structure of a complex of the SF1NTD with the C-terminal U2AF homology motif domain of U2AF65 (U2AF65UHM) reveals that, in addition to the known U2AF65UHM-SF1 interaction, the helix-hairpin domain forms a secondary, hydrophobic interface with U2AF65UHM, which locks the orientation of the two subunits. Mutational analysis shows that the helix hairpin is essential for cooperative formation of the ternary SF1-U2AF65-RNA complex. We further show that tandem serine phosphorylation of a conserved Ser80-Pro81-Ser82-Pro83 motif rigidifies a long unstructured linker in the SF1 helix hairpin. Phosphorylation does not significantly alter the overall conformations of SF1, SF1-U2AF65 or the SF1-U2AF65-RNA complexes, but slightly enhances RNA binding. Our results indicate that the helix-hairpin domain of SF1 is required for cooperative 3′-splice site recognition presumably by stabilizing a unique quaternary arrangement of the SF1-U2AF65-RNA comple

Ferroptosis: new insight into the mechanisms of diabetic nephropathy and retinopathy

Diabetic nephropathy (DN) and diabetic retinopathy (DR) are the most serious and common diabetes-associated complications. DN and DR are all highly prevalent and dangerous global diseases, but the underlying mechanism remains to be elucidated. Ferroptosis, a relatively recently described type of cell death, has been confirmed to be involved in the occurrence and development of various diabetic complications. The disturbance of cellular iron metabolism directly triggers ferroptosis, and abnormal iron metabolism is closely related to diabetes. However, the molecular mechanism underlying the role of ferroptosis in DN and DR is still unclear, and needs further study. In this review article, we summarize and evaluate the mechanism of ferroptosis and its role and progress in DN and DR, it provides new ideas for the diagnosis and treatment of DN and DR

The Ginger-shaped Asteroid 4179 Toutatis: New Observations from a Successful Flyby of Chang'e-2

On 13 December 2012, Chang'e-2 conducted a successful flyby of the near-Earth asteroid 4179 Toutatis at a closest distance of 770 $\pm$ 120 meters from the asteroid's surface. The highest-resolution image, with a resolution of better than 3 meters, reveals new discoveries on the asteroid, e.g., a giant basin at the big end, a sharply perpendicular silhouette near the neck region, and direct evidence of boulders and regolith, which suggests that Toutatis may bear a rubble-pile structure. Toutatis' maximum physical length and width are (4.75 $\times$ 1.95 km) $\pm$10$\%$, respectively, and the direction of the +$z$ axis is estimated to be (250$\pm$5$^\circ$, 63$\pm$5$^\circ$) with respect to the J2000 ecliptic coordinate system. The bifurcated configuration is indicative of a contact binary origin for Toutatis, which is composed of two lobes (head and body). Chang'e-2 observations have significantly improved our understanding of the characteristics, formation, and evolution of asteroids in general.Comment: 21 pages, 3 figures, 1 tabl

ATP-Responsive and Near-Infrared-Emissive Nanocarriers for Anticancer Drug Delivery and Real-Time Imaging

Stimuli-responsive and imaging-guided drug delivery systems hold vast promise for enhancement of therapeutic efficacy. Here we report an adenosine-5'-triphosphate (ATP)-responsive and near-infrared (NIR)-emissive conjugated polymer-based nanocarrier for the controlled release of anticancer drugs and real-time imaging. We demonstrate that the conjugated polymeric nanocarriers functionalized with phenylboronic acid tags on surface as binding sites for ATP could be converted to the water-soluble conjugated polyelectrolytes in an ATP-rich environment, which promotes the disassembly of the drug carrier and subsequent release of the cargo. In vivo studies validate that this formulation exhibits promising capability for inhibition of tumor growth. We also evaluate the metabolism process by monitoring the fluorescence signal of the conjugated polymer through the in vivo NIR imaging