Cooperative lattice coding and decoding in half-duplex channels

We propose novel lattice coding/decoding schemes for half-duplex outage-limited cooperative channels. These schemes are inspired by the cooperation protocols of Azarian et al. and enjoy an excellent performance-complexity tradeoff. More specifically, for the. relay channel, we first use our lattice coding framework to generalize Yang and Belfiore implementation of the non-orthogonal amplify and forward cooperation protocol. This generalization is shown to offer significant performance gains while keeping the decoding complexity manageable. We then devise a novel variant of the dynamic decode and forward protocol, along with a lattice-coded implementation, which enjoys a near-optimal diversity-multiplexing tradeoff with a low encoding/decoding complexity. Finally, for the cooperative multiple-access channel, we present a lattice-coded implementation of the non-orthogonal amplify and forward protocol and demonstrate its excellent performance-complexity tradeoff. Throughout the paper, we establish the performance gains of our proposed protocols via a comprehensive simulation study     

BIOSORPTION STUDIES ON NACL-MODIFIED CERATOPHYLLUM DEMERSUM: REMOVAL OF TOXIC CHROMIUM FROM AQUEOUS SOLUTION

The present research provides information on the Cr(VI) removal potential of NaCl-modified Ceratophyllum demersum, an aquatic plant biomass. The effects of various parameters including pH, biomass dosage, contact time, and initial concentration on Cr(VI) biosorption were investigated. The best conditions for Cr(VI) biosorption in the present study were: pH of 2, biosorbent dose of 8 g/L, and contact time of 60 min. Under these conditions, maximum adsorption capacity of modified C. demersum for Cr(VI) was 10.20 mg/g. The experimental biosorption data were modeled by Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherms. The biosorption process followed the Langmuir isotherm model with a high coefficient of determination (R² > 0.99). The biosorption process followed pseudo-second-order kinetics. Further, the biosorbent was characterized by Fourier transform-infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). The results showed that biosorption of Cr(VI) on NaCl-modified C. demersum occurred through chemical sorption.     

Mechanical and gelling properties of comminuted sausages containing chicken MDM

The present investigation focuses on the physicochemical properties, rheological behaviors and texture of raw and cooked emulsions containing different mechanically deboned meat (MDM) from chicken. MDMs were produced from the neck, backs and thighs. The texture and mechanical profile analyses were performed using a small deformation dynamic oscillation in a shear and instrumental texture analyzer. The mechanical spectra of the raw and cooked MDM emulsion gels were classified as weak gels based on their frequency sweep and tan δ results. Both the G′ and G″ values increased with increasing frequency in the temperature of 4 and 10 °C. The MDM from thighs had the lowest water holding capacity (WHC) and emulsifying (EC) values, while the MDM from backs had significant values of 2.41 and 128.87, respectively. The cooked emulsion containing backs showed the highest hardness and cohesiveness values, while the emulsion containing necks and thighs had the lowest texture parameters.     

Controlled synthesis and photocatalytic activities of barium hexaferrite nanoparticles and examine decolorization methyl orange on liver of rats

The controlled morphological of magnetic nanoparticles have gained great importance in a wide variety of applications due to their promising physico-chemical properties. Therefore, in this study, barium hexaferrite (BaFe₁₂O₁₉) nanoparticles were prepared with the simplest and most efficient chemical route, the two-step sol–gel method, in the presence of seven different and widely used surfactants. The aim of this research is to investigate the influence of the different surfactants on the morphology and particle size of the BaFe₁₂O₁₉ nanoparticles; therefore, different techniques were employed in order to elucidate the composition and structure of the BaFe₁₂O₁₉ nanoparticles such as XRD, SEM, FT-IR, and EDX. The magnetic properties were investigated by measuring the hysteresis loops. In order to investigate the role of BaFe₁₂O₁₉ nanoparticles as the photocatalysts, decolorization of methyl orange under ultraviolet light irradiation was also evaluated. In addition, the purity of decolorized water was examined by investigating its effect on the health condition of liver of rats.     

Analysis of biofilm growth in the presence of osmotic pressure and temperature effects

Transient mass transfer in a diffusion–reaction biofilm with a moving boundary was investigated analytically. The analysis incorporates both the diffusion processes into the biofilm as well as the reaction processes that lead to the expansion of the system. For first and second order reaction terms, the biofilm synthesis as a function of time was presented. The temporal development of the biomass was found to be in very good agreement with numerical results. The effects of osmotic pressure and temperature were also investigated and it was found that osmotic pressure plays a significant role in first order reactions but the temperature dependence is primarily found in the reaction kinetics and does not significantly influence osmotic pressure effects.     

Optical properties of wounds: diabetic versus healthy tissue

Diffuse photon density wave (DPDW) methodology at Near Infrared frequencies has been used to calculate absorption and scattering from wounds of healthy and diabetic rats. The diffusion equation for semi-infinite media is being used for calculating the absorption and scattering coefficients based on measurements of phase and amplitude with a frequency domain device. Differences observed during the course of healing in the two populations can be correlated to the delayed healing observed in diabetics. These results are encouraging and further work will focus on the implementation of this device to the clinical setting as a monitoring tool in chronic diabetic wounds.     

Structural investigation and response surface optimisation for improvement of kefiran production yield from a low-cost culture medium

Kefiran, a water-soluble heteropolysaccharide with molecular weight of 1.35 × 10⁶ Da and a specific optical rotation of +64° (c 1.0, H₂O), was isolated from kefir grains grown in cheese whey and further purified through DEAE-Sepharose XK26. Response surface methodology was employed to optimise the culture conditions for kefiran production from kefir grains to be lactose concentration 67 g/l, yeast extract 13 g/l, pH 5.7 and temperature 24 °C. Intrinsic viscosity was 5.84 dl/g using the Huggins extrapolation and 5.53 dl/g using the Kramer extrapolation. Monosaccharide analysis revealed that kefiran is composed of glucose (Glc) and galactose (Gal) in a relative molar ratio of 1.0:1.1. Its structural features were elucidated by a combination of FT-IR, methylation and GC–MS analysis, periodate oxidation–Smith degradation, partial acid hydrolysis and NMR spectroscopy (¹H, ¹³C and HMBC). The data obtained indicated that kefiran possessed a backbone of (1 → 6)-linked Glc, (1 → 3)-linked Gal, (1 → 4)-linked Gal, (1 → 4)-linked Glc and (1 → 2,6)-linked Gal, with a branch attached to O-2 of Gal residues and terminated with Glc residues.     

Estimation of phase wave-front aberration distribution function using wavelet transform profilometry

Reduction of image quality under the effects of wavefront aberration of the optical system has a direct impact on the vision system's performance. This paper tries to estimate the amount of aberration with the use of wavelet transform profilometry. The basic idea is based on the principle that under aberration effects, the position of the fringes' image on the image plane will change, and this change correlates with the amount of aberration. So the distribution of aberration function can directly be extracted through measuring the amount of changes in the fringes' image on the image plane. Experimental results and the empirical validity of this idea are evaluated.     

Time-domain analysis of lossy active transmission lines using FDTD method

In this paper, an accurate and efficient method for analysis of a GaAs MESFET including frequency-dependent losses of the electrodes in the time domain is presented. The time domain analysis is obtained based on the fully distributed model using finite-difference time-domain (FDTD) technique, with the assumption of the skin effect losses. The time-domain results are verified using the conventional time-domain to frequency-domain (TDFD) solution technique.