Evaluation of the evolution of relationships between topics over time

Topics that attract public attention can originate from current events or developments, might be influenced by situations in the past, and often continue to be of interest in the future. When respective information is made available textually, one possibility of detecting such topics of public importance consists in scrutinizing, e.g., appropriate press articles using—given the continual growth of information—text processing techniques enriched by computer routines which examine present-day textual material, check historical publications, find newly emerging topics, and are able to track topic trends over time. Information clustering based on content-(dis)similarity of the underlying textual material and graph-theoretical considerations to deal with the network of relationships between content-similar topics are described and combined in a new approach. Explanatory examples of topic detection and tracking in online news articles illustrate the usefulness of the approach in different situations.     

Atomic decompositions and Hardy’s inequality on weak Hardy-Morrey spaces

We introduce the weak Hardy-Morrey spaces in this paper. We also obtain the atomic decompositions of the weak Hardy-Morrey spaces. By using these decompositions, we establish the Hardy inequalities on the weak Hardy-Morrey spaces.     

A mod 2 index theorem for pin<Superscript>−</Superscript> manifolds

We establish a mod 2 index theorem for real vector bundles over 8k + 2 dimensional compact pin^? manifolds. The analytic index is the reduced η invariant of (twisted) Dirac operators and the topological index is defined through KO-theory. Our main result extends the mod 2 index theorem of Atiyah and Singer (1971) to non-orientable manifolds.     

Multi-recurrence and van der Waerden systems

We explore recurrence properties arising from dynamical approach to the van der Waerden theorem and similar combinatorial problems. We describe relations between these properties and study their consequences for dynamics. In particular, we present a measure-theoretical analog of a result of Glasner on multi-transitivity of topologically weakly mixing minimal maps. We also obtain a dynamical proof of the existence of a C-set with zero Banach density.     

Quasi-triangular Hopf algebras and invariant Jacobians

We show that two module homomorphisms for groups and Lie algebras established by Xi can be generalized to the setting of quasi-triangular Hopf algebras. These module homomorphisms played a key role in his proof of a conjecture of Yau (1998). They will also be useful in the problem of decomposition of tensor products of modules. Additionally, we give another generalization of result of Xi in terms of Chevalley-Eilenberg complex.     

Estimated conditional score function for missing mechanism model with nonignorable nonresponse

Missing data mechanism often depends on the values of the responses, which leads to nonignorable nonresponses. In such a situation, inference based on approaches that ignore the missing data mechanism could not be valid. A crucial step is to model the nature of missingness. We specify a parametric model for missingness mechanism, and then propose a conditional score function approach for estimation. This approach imputes the score function by taking the conditional expectation of the score function for the missing data given the available information. Inference procedure is then followed by replacing unknown terms with the related nonparametric estimators based on the observed data. The proposed score function does not suffer from the non-identifiability problem, and the proposed estimator is shown to be consistent and asymptotically normal. We also construct a confidence region for the parameter of interest using empirical likelihood method. Simulation studies demonstrate that the proposed inference procedure performs well in many settings. We apply the proposed method to a data set from research in a growth hormone and exercise intervention study.     

Glycyl-alanyl-histidine protects PC12 cells against hydrogen peroxide toxicity

Background

Peptides with cytoprotective functions, including antioxidants and anti-infectives, could be useful therapeutics. Carnosine, β-alanine-histidine, is a dipeptide with anti-oxidant properties. Tripeptides of Ala-His-Lys, Pro-His-His, or Tyr-His-Tyr are also of interest in this respect.

Results

We synthesized several histidine-containing peptides including glycine or alanine, and tested their cytoprotective effects on hydrogen peroxide toxicity for PC12 cells. Of all these peptides (Gly-His-His, Ala-His-His, Ala-His-Ala, Ala-Ala-His, Ala-Gly-His, Gly-Ala-His (GAH), Ala-His-Gly, His-Ala-Gly, His-His-His, Gly-His-Ala, and Gly-Gly-His), GAH was found to have the strongest cytoprotective activity. GAH decreased lactate dehydrogenase (LDH) leakage, apoptosis, morphological changes, and nuclear membrane permeability changes against hydrogen peroxide toxicity in PC12 cells. The cytoprotective activity of GAH was superior to that of carnosine against hydrogen peroxide toxicity in PC12 cells. GAH also protected PC12 cells against damage caused by actinomycin D and staurosporine. Additionally, it was found that GAH also protected SH-SY5Y and Jurkat cells from damage caused by hydrogen peroxide, as assessed by LDH leakage.

Conclusion

Thus, a novel tripeptide, GAH, has been identified as having broad cytoprotective effects against hydrogen peroxide-induced cell damage.

     

Preparation and Characterization of Functionalized Polyaniline-Based Nanocomposite as an Antibacterial Agent

Polyaniline-co-phenylenediamine (PAn/PDA) nanocomposite has been prepared in the aqueous medium using sodium dodecyl benzene sulfonate (DBSNa) and hydroxypropylcellulose (HPC) as a surfactant. The tests used in this research to characterize the products were SEM, TEM, FTIR, UV–Visible and TGA for morphology, particle size, chemical structure and stability. The results confirm that the spherical nanocomposites (40–90 nm) were formed with high thermal stability. It is shown in the results that the physicochemical properties of poly(alkyl substituted anilines) are depended on the substituent groups that are bonded to N-position. The prepared nanocomposites were then tested for the antibacterial properties against three pathogenic strains. The antibacterial properties of nanocomposites were investigated by disk diffusion, minimum inhibitory concentration (MIC), minimum bactericidal concentrations (MBC), and bactericidal kinetic methods. The disk diffusion result indicated that the diameter of the inhibition zones of PAn/PDA–HPC nanocomposite was 9, 11, and 10 mm against E. coli, P. aeruginosa, and S. aureus respectively. It was found that the value of MIC of PAn/PDA–HPC nanocomposite against E. coli, P. aeruginosa and S. aureus were 2.5, 1.25 and 2.5 mg/mL respectively. The evaluation results revealed the PAn/PDA–HPC nanocomposite exhibited excellent inhibitory activity against both gram-negative and gram-positive bacteria.     

Synthesis and Thermal Performance of Polyurea Microcapsulated Phase Change Materials by Interfacial Polymerization

Microencapsulated phase change materials with paraffin as the core material were synthesized by interfacial polymerization of isophorone diisocyanate with diethylene triamine. The particle size and particle size distribution, morphology, thermal performance and the encapsulation efficiency of the prepared materials were investigated. The results of Fourier transform infrared spectrometer and X-ray photoelectron spectroscopy suggested that the paraffin core was well encapsulated by the polyurea resin. The particle size of the prepared materials decreased and its distribution became narrow with the increase of the emulsification time, stirring speed and emulsifier amount. The thermal gravimetric analysis indicated that the prepared materials exhibited good thermal stability, while the differential scanning calorimetry their high encapsulation efficiency.