Synthesis,Optimal Fabrication,and Physico-Mechanical Property Evaluation of PCL-b-PLLA Diblock Copolymer-Based Nanoscale Roughness Textured Electrospun Mats

Poly(ɛ-caprolactone)-block-poly(L-lactide) (PCL-b-PLLA) diblock copolymer and its electrospun mats (EMs) are characterized for their microstructural, thermal, and physico-mechanical properties. The EMs of synthesized copolymer exhibiting the optimal level of average fiber diameter (Co-FD) and diameter variation (Co-SD) are obtained following Taguchi's design of experiments (DOE). Electrospinning process parameters such as solution concentration, DMF content in CF/DMF solvent mixture, and applied voltage are varied at three different levels (L₉). Analysis of variance (ANOVA) indicated DMF content to be the major influencing factor on FD and SD of EMs with ∼95% confidence. Regression model indicated ∼88% accuracy in predicting the FD of the copolymer-based EMs. The physico-mechanical properties of the optimized EMs are evaluated vis-à-vis the influence of FD and SD on the mechanical properties. Atomic force microscopy revealed solvent evaporation induced radial inconsistencies, desirable in terms of nanoscale surface roughness, which is higher for Co-SD (∼600 nm) than in Co-FD (∼400 nm). The swelling and weight loss showed marked improvement in PCL-b-PLLA based EMs reiterating the possibility of their enhanced compatibility as biomedical materials.     

TINB: a topical interaction network builder from WWW

Wireless Networks - Social network is a collection of people generally called ‘actors’ who are connected to each other based on some association criteria like a friend, follow,...     

An intelligent approach for fingerprint presentation attack detection using ensemble learning with improved local image features

Multimedia Tools and Applications - The fingerprint-based authentication systems are being extensively deployed as security tool for providing access to the critical Cyber Physical Systems (CPS)....     

Wrap‐around electrodes for microLED tiled displays

The authors have developed a process to create wrap‐around electrodes (WAEs) on glass for use in tiled microLED display applications. The electrodes have small size and spacing, low resistance, and good reliability. In addition, an opaque overcoat protects the edges of the tiles and reduces seam visibility. These electrodes allow bezel‐free tiled operation for high‐resolution displays.     

FUCA: Fuzzy‐based unequal clustering algorithm to prolong the lifetime of wireless sensor networks

Wireless sensor network comprises billions of nodes that work collaboratively, gather data, and transmit to the sink. “Energy hole” or “hotspot” problem is a phenomenon in which nodes near to the sink die prematurely, which causes the network partition. This is because of the imbalance of the consumption of energy by the nodes in wireless sensor networks. This decreases the network's lifetime. Unequal clustering is a technique to cope up with this issue. In this paper, an algorithm, “fuzzy‐based unequal clustering algorithm,” is proposed to prolong the lifetime of the network. This protocol forms unequal clusters. This is to balance the energy consumption. Cluster head selection is done through fuzzy logic approach. Input variables are the distance to base station, residual energy, and density. Competition radius and rank are the two output fuzzy variables. Mamdani method is employed for fuzzy inference. The protocol is compared with well‐known algorithms, like low‐energy adaptive clustering hierarchy, energy‐aware unequal clustering fuzzy, multi‐objective fuzzy clustering algorithm, and fuzzy‐based unequal clustering under different network scenarios. In all the scenarios, the proposed protocol performs better. It extends the lifetime of the network as compared with its counterparts.     

Modulation of macrophage activation by ammonium metavanadate

The molecular basis of the immunotoxic effect of ammonium metavanadate on signal transduction involved in macrophage activation was studied in resident peritoneal macrophages (PEM) and a murine macrophage-like cell line, J774. A fourfold elevation in cytosolic free calcium levels was observed within 10 s following lipopolysaccharide (LPS) stimulation of the non-vanadate-exposed controls both in vitro and in vivo; the levels returned to prestimulation values within 70 s. Exposure to phorbol ester (PMA) did not result in any appreciable change in cytosolic free calcium levels. Compared to untreated controls, treatment with vanadate caused a significant elevation in basal cytosolic calcium levels. Such elevation was not enhanced further by LPS. LPS stimulation of macrophages also resulted in a significant elevation of membrane-associated protein kinase C (PKC) activity, which was, however, inhibited in a dose-dependent manner by vanadate in both in vitro and in vivo studies. Exposure to PMA also resulted in a significant elevation of membrane-associated PKC activity; vanadate treatment at lower levels did not cause downregulation, indicating that vanadate at these levels interfered with the receptor-mediated events rather than the enzyme directly. Vanadate at higher exposure levels inhibited the activity even in PMA-stimulated macrophages. No significant difference occurred in cytosolic PKC activities in control macrophages; vanadate treatment at lower levels resulted in a significant elevation of cytosolic PKC activities following stimulation with LPS or PMA, indicating that vanadate might be interfering with the translocation process.     

Synthesis and characterization of dextrin‐grafted polypropylene

We carried out the graft copolymerization of the water‐soluble natural polymer dextrin onto preirradiated polypropylene (PP) in an aqueous medium using benzoyl peroxide (BPO) as the radical initiator. PP was irradiated by γ rays from a Co⁶⁰ source at a constant dose rate of 3.40 kGy/h to introduce hydroperoxide linkages, which served as the sites for grafting. The graft copolymerization was studied as a function of different reaction parameters, and the maximum percentage grafting (P_g; 55%) of dextrin onto PP was obtained at optimum conditions of [BPO] = 5.165 × 10⁻² mol/L, temperature = 60°C in 120 min with 15 mL of water. Different grafting parameters, such as the percentage apparent grafting, percentage grafting, and percentage true grafting have been evaluated. The graft copolymers were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy. Swelling studies were carried out in pure, binary, ternary, and quaternary solvent systems composed of water, ethanol (EtOH), dimethyl sulfoxide (DMSO), and N,N‐dimethylformamide (DMF) at different ratios. The maximum swelling percentage PP‐g‐dextrin (both composite and true graft) was observed in pure DMSO and DMF followed by EtOH and water. Water‐retention studies of PP and PP‐g‐dextrin (both composite and true graft) were investigated at different time periods, temperatures, and pH values. The maximum percentage water retention of PP‐g‐dextrin (composite, 124%) was observed at 8 h and 50°C in a neutral medium (pH 7). © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Bus encoder design for reduced crosstalk,power and area in coupled VLSI interconnects

This research work presents a novel circuit for simultaneous reduction of power, crosstalk and area using bus encoding technique in RC modeled VLSI interconnect. Bus-invert method is used to reduce inter-wire coupling, which is actually responsible for crosstalk, delay and power dissipation in coupled interconnects. The proposed method focuses on simplified and improved encoder circuit for 4, 8 and 16 coupled lines. In past, the researchers developed encoders that usually focused on minimizing power dissipation and/or crosstalk, thereby paying heavy penalty in terms of chip area. However, the proposed encoder and decoder while significantly reducing crosstalk demonstrates an overall reduction of power dissipation by 68.76% through drastically limiting switching activity. Furthermore, while reducing the complexity, chip area and transistor count of the circuit is reduced by more than 57%.