Dynamic tensile and shear storage moduli of PEG/silica-polymorph composites

The effect of silica polymorphs on the thermomechanical properties of 0, 5, 10, and 20 wt % silica particles-reinforced-based poly(ethylene glycol) (PEG) composites have been studied as a function of temperature using dynamic mechanical analysis (DMA). The silica polymorphs exhibited quartz (Q), cristobalite (C), and amorphous (A) phases, which were obtained by processing natural silica sand. The DMA thermomechanical properties were determined in tensile (E) and shear (G) modes. The maximum storage moduli (E′ and G′) were achieved by samples with 20 wt % silica for all type of fillers. These values increased approximately 12 times for PEG/Q, 10 times for PEG/A, and 11 times for PEG/C composites compared to the pure PEG. Furthermore, the Poisson's ratio values of the composites were filler phase dependent, that is, 0.39–0.47 for PEG/Q, 0.15–0.18 for PEG/A, and somewhat anomalous for PEG/C composites. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47372.     

Effects of natural weathering on the degradation of alkaline‐treated peanut shell filled recycled polypropylene composites

The present work evaluates the potential of the natural filler peanut shell powder (PSP) on the properties and degradation behavior of alkaline‐treated PSP filled recycled polypropylene (RPP) composites. For this purpose, 0–40 wt% of untreated PSP and hydrogen peroxide‐treated PSP were incorporated into RPP composites that were fabricated via a melt‐mixing molding system. The fabricated composites were exposed to the natural environment of Penang, Malaysia for 6 months. The properties of both untreated and treated RPP/PSP composites were assessed. Results showed that the tensile properties of the treated RPP/PSP composites were higher than that of the untreated RPP/PSP composites. The treated RPP/PSP composites were less affected by weathering degradation compared to the untreated RPP/PSP composites. An increase in the carbonyl index of both composites also confirmed that some degradation had taken place. On comparing the crystallinity of both composites, the treated composites showed lower crystallinity than untreated composites. J. VINYL ADDIT. TECHNOL., 25:26–34, 2019. © 2018 Society of Plastics Engineers     

Differential Action of Connexin Hemichannel and Pannexin Channel Therapeutics for Potential Treatment of Retinal Diseases

Dysregulation of retinal function in the early stages of light-induced retinal degeneration involves pannexins and connexins. These two types of proteins may contribute to channels that release ATP, leading to activation of the inflammasome pathway, spread of inflammation and retinal dysfunction. However, the effect of pannexin channel block alone or block of both pannexin channels and connexin hemichannels in parallel on retinal activity in vivo is unknown. In this study, the pannexin channel blocker probenecid and the connexin hemichannel blocker tonabersat were used in the light-damaged rat retina. Retinal function was evaluated using electroretinography (ERG), retinal structure was analyzed using optical coherence tomography (OCT) imaging and the tissue response to light-induced injury was assessed immunohistochemically with antibodies against glial fibrillary acidic protein (GFAP), Ionized calcium binding adaptor molecule 1 (Iba-1) and Connexin43 (Cx43). Probenecid did not further enhance the therapeutic effect of connexin hemichannel block in this model, but on its own improved activity of certain inner retina neurons. The therapeutic benefit of blocking connexin hemichannels was further evaluated by comparing these data against results from our previously published studies that also used the light-damaged rat retina model. The analysis showed that treatment with tonabersat alone was better than probenecid alone at restoring retinal function in the light-damaged retina model. The results assist in the interpretation of the differential action of connexin hemichannel and pannexin channel therapeutics for potential treatment of retinal diseases.     

Synthesis of a Kind of Temperature-responsive Cell Culture Surface for Corneal Sheet

In this study,acrylic acid(AA) and 4-azidoaniline were used to modify poly(N-isopropylacrylamide)(NIPAAm) in order to fabricate temperature-responsive surface for corneal epithelia cell adhesion and detachment.First,NIPAAm was copolymerized with acrylic acid.Then,the copolymer was coupled with azidoaniline to synthesize AzPhPIA,derivative of p(NIPAAm-co-AA),which possesses both thermo-and photo-sensitivities.Second,the synthesized copolymer was characterized by high performance liquid chromatography(HPLC),F...     

Review on Progressive Freeze Concentration Designs

Progressive freeze concentration (PFC) is a process where only a large single ice crystal is formed in the system and grown on the cooling surface so that the separation between the ice crystal and the mother solution is very easy. This makes the system very simple and leads to a lower cost. The conventional setup of PFC produces ice with high purity but lower productivity than suspension freeze concentration (SFC). The volume of ice produced is also usually low. Hence, continued areas of the development for PFC system include the quest for improved productivity and better efficiency. Different kinds of design have been investigated, which are easy to operate and cost-effective besides the ability to obtain high quality of product and better efficiency of the system. The PFC system is recognized as a good alternative if high-quality products can be produced with higher productivity. In this article, previous researches on PFC designs were reviewed for the purpose of providing an understanding on methods of designing a PFC system and also to provide references for future application of PFC.     

Self-generation of reward by logarithmic transformation of multiple sensor evaluations

Artificial Life and Robotics - Although the design of the reward function in reinforcement learning is important, it is difficult to design a system that can adapt to a variety of environments and...     

Feature Selection and Extraction Methods for Power Systems Transient Stability Assessment Employing Computational Intelligence Techniques

One of the important aspects in achieving better performance for transient stability assessment (TSA) of power systems employing computational intelligence (CI) techniques is by incorporating feature reduction techniques. For small power system the number of features may be small but when larger systems are considered the number of features increased as the size of the systems increases. Apart from employing faster CI techniques to achieve faster and accurate TSA of power system, feature reduction techniques are needed in reducing the input features while preserving the needed information so as to make faster training of the CI technique. This paper presents feature reductions techniques used, namely correlation analysis and principle component analysis, in reducing number of input features presented to two CI techniques for TSA, namely probabilistic neural network (PNN) and least squares support vector machines (LS-SVM). The proposed feature reduction techniques are implemented and tested on the IEEE 39-bus test system and 87-bus Malaysia’s power system. Numerical results are presented to demonstrate the performance of the feature reduction techniques and its effects on the accuracies and time taken for training the two CI techniques.     

LPP solution schemes for use with face recognition

Locality preserving projection (LPP) is a manifold learning method widely used in pattern recognition and computer vision. The face recognition application of LPP is known to suffer from a number of problems including the small sample size (SSS) problem, the fact that it might produce statistically identical transform results for neighboring samples, and that its classification performance seems to be heavily influenced by its parameters. In this paper, we propose three novel solution schemes for LPP. Experimental results also show that the proposed LPP solution scheme is able to classify much more accurately than conventional LPP and to obtain a classification performance that is only little influenced by the definition of neighbor samples.