Design Methodology of a Low-Energy Reconfigurable Single-Chip DSP System

In this paper, we first present a reconfigurable architecture template for low-power digital signal processing, and then an energy conscious design methodology to bridge the algorithm to architecture gap. The energy efficiency of such an architecture and the effectiveness of the methodology are demonstrated in case study implementations targeting baseband voice processing and digital signal processing.     

Investigation of platelet activation and calcium store release by a topical hemostatic xerogel dressing for improved blood clotting

Adequate topical hemostatic dressings are required as first-line approach for reduction of uncontrolled hemorrhage, a leading cause of mortalities. Platelets play a major role during blood clotting to prevent hemorrhage during injuries. Here, we demonstrate the mechanisms activated through protease activating receptor 1 (PAR1), a platelet membrane protein in response to a porous composite xerogel dressing incorporating SiNPs (size 122 ± 10 nm) and calcium (2.5 mM), characterized by scanning electron microscopy–energy dispersive x-ray spectroscopy and Fourier transform infrared spectroscopy. The composite displayed 13.9-fold improved blood clotting index in comparison to commercial dressing. The composite displayed increased platelet aggregation due to development of well-formed pseudopodia as compared to bare xerogel, SFLLRN (a thrombin mimic), adenosine di-phosphate (a platelet activator), and heparin (a thrombin inhibitor). Further, PAR1 gene was significantly upregulated in model A549 epithelial cell line (1.2-fold) and human platelets (1.4-fold). The composite enhanced calcium release and its extrusion in A549 cells. Upregulation of PAR1 on the platelet surface and calcium release are crucial for platelet shape change and aggregation. The data indicate that xerogel composite containing SiNPs and calcium enhanced blood clotting through activation of PAR1. Such dressings can provide a potential hemostatic solution to reduce blood loss, disability, and mortality during surgery and trauma care.     

Structural and physical characteristics of Au2O3-doped sodium antimonate glasses – Part II electrical characteristics

In continuation of our earlier investigations on structural and physical characteristics of Au₂O₃-doped sodium antimonate glass-ceramics (Part-1), in this part we have investigated the influence of gold ions on electrical characteristics of the Na₂O–Sb₂O₃: Au₂O₃ glass-ceramics. The study contains the results of quantitate investigations on dielectric properties, impedance spectra and A.C. conductivity in larger ranges of continuous frequencies (4 Hz-8 MHz) and temperatures (300-630 K). The variations exhibited by dielectric parameters with temperature and also with frequency were discussed in terms of various polarization mechanisms. The observed dielectric relaxation effects were analyzed using pseudo Cole-Cole plot method and the analysis indicated spreading of relaxation times for dipoles. A.c. conductivity and also d.c. conductivity were found to decrease (to three orders of magnitude) with increase in Au₂O₃ concentration upto 0.1 mol%. The decrement is ascribed to the increasing concentration of Sb⁵⁺ ions that were predicted to participate in the glass network forming with SbO₄ units. Even though, both ionic and polaronic contributions are possible for conduction in the studied material, quantitative analysis of these results indicated that the polaronic conduction (due to intervalence transfer between Sb³⁺ ↔ Sb⁵⁺ and Au⁰ ↔ Au³⁺) is prevalent. The results have also suggested that there is a gradual decrement in the ionic component with increase in Au₂O₃ concentration. Variation in σ_ac in the low-temperature region could satisfactorily be explained using quantum mechanical tunneling (QMT) model. Analysis of the results of d.c. conductivity indicated that the small polaron hoping (SPH) model is valid, especially in a high-temperature region while the low temperature part of d.c. conductivity is analyzed based on variable range hopping (VRH) model. Overall, the increase in Au₂O₃ dopant concentration in the studied glass-ceramics caused a decrement in the magnitude of the conductivity or increase in the insulating strength of the material.     

Improving injection efficiency of gate modulation ROIC interface for HgCdTe IR photodiodes

Microsystem Technologies - A new interface circuit for readout of HgCdTe Infrared photodiodes is proposed that can be used for efficient transfer of photocurrent from the photodiodes to the...     

Influence of Binder Type on Color Characteristics of Cotton Fabric Colored with a Photochromic Colorant

Photochromic colorants change rapidly and reversibly from colorless to colored state when activated by ultraviolet radiation. They can be applied on textile substrates with use of organic binders. Different type of binders and their concentration may have a significant effect on color development and other related properties. In this work, a study of the effect of binder type at different concentrations on the color development, wash fastness and some comfort characteristics is undertaken. It was found that while these properties vary with binder type and concentration, the best color development is obtained at an optimum concentration of 5% binder. The presence of binder may affect comfort related properties of the fabrics, such as stiffness, water absorbency, air permeability, sometimes quite adversely. Hence a careful selection of the binder type is needed depending on the most important requirement in the colored fabrics.     

Structural,spectroscopic and optical properties of pure and gadolinium doped neodymium phosphate nanoparticles prepared using wet chemical route

ABSTRACT

Nanoparticles of neodymium phosphate and 5% gadolinium (Gd) doped neodymium phosphate prepared by co-precipitation technique belong to the monoclinic monazite phase with space group P2_1/n. The average crystallite size calculated using Debye-Scherrer and Williamson Hall method matches very well with grain size observed from scanning electron microscope images and Image J software. FTIR analysis signifies the presence of vibration modes along with the phosphate group and a slight shift in wave number was observed with the substitution of gadolinium into neodymium phosphate. Ultraviolet absorption spectrophotometer show transitions from ground state to various excited state within the 4f shell and the absorption edge shifts towards the lower wavelength side (blue shift) with the addition of dopant. Raman spectrum further confirms the formation of phosphate group with relevant peaks.     

Effect of γ‐irradiation on glycolysis of PET waste and preparation of ecofriendly coatings using bio‐based and recycled materials

Recycling of postconsumer poly (ethylene terephthalate) (PET) is a worldwide concern due to large increasing volume of these materials produced by society. In the present study, we report the effect of gamma irradiation on degradation of PET and its subsequent effect on glycolysis by using excess ethylene glycol (EG). The results as analyzed by molecular weight determination showed that extent of depolymerization of PET were dose dependent. The doses of 30, 50, 70, and 100 kGy resulted in decrease in the molecular weight by about 15%, 25%, 30%, and 40% respectively. The irradiated waste PET samples were further subjected to glycolysis using EG by conventional and microwave method which resulted in increased yield of monomeric product, bis (2‐hydroxyethylterephthalate) (BHET). The recycled material, BHET, was then used in combination with bio‐based monomers to prepare a new eco‐friendly polyester polyol which was analyzed for hydroxyl, saponification, acid value and further characterized by FTIR, ¹HNMR, and GPC techniques for molecular weight determination. Polyurethane coatings were prepared from the polyester polyol and various commercial polyisocyanate curing agents. The coated films were evaluated for their performance properties. Thermal properties of coatings were investigated by differential scanning calorimetry and thermogravimetric analysis. POLYM. ENG. SCI., 55:2653–2660, 2015. © 2015 Society of Plastics Engineers