Modern consumer appliances such as wireless communication and multimedia systems present very strong requirements for the digital parts of these systems: digital design process must provide solutions which offer high performance, flexibility for multifunctional use, and energy efficiency. Over the past decade, the reconfigurable computing platform has been an emerging approach in scientific research and in practical implementations to meet these requirements. The paper, “Design of Partially Reconfigurable Computing System and Implementation on Virtex-4 FPGA” by Sandeep Sharma, Ashutosh Gupta, Manoj Duhan and Solomon Raju Kota presents the methodological algorithm of partial reconfiguration flow for execution and implementation of reconfigurable modules on Xilinx Virtex-4(XC4VFX12) device. The design of the interface controller through UART for 32-bit RM was discussed. All the modules were designed and simulated with supporting simulation tool using ModelSim-6.0d and synthesized with Xilinx 9.1.02i_PR10 (ISE).

Using Microwave reflection to determine the moisture content of soil relies on change in the dielectric constant of soil with moisture content. This in turn affects the emission and reflection of energy from the soil. In the paper, “Viewing Angle-Dependent Microwave Reflection Studies on Moisture-Laden Black Soil”, the authors, Vijaya Puri, S S Nalawade and M S Patil, report the angle-dependent microwave reflection studies on the X (8-12 GHz) and Ku (12.4-18 GHz) bands of two types of moisture-laden black soils.

All the soil samples were taken from Kolhapur district in Maharashtra, India. Standard gain horn antenna was used to study the attenuation of microwaves in the reflection mode. The authors concluded that at angles of reflection of 90° and 75°, the sensitivity of the instrument to moisture content was very high. It was also concluded that microwave in the frequency range 16.5 GHz to 17.2 GHz was more useful for detecting the type of soil.

Multifunctional reactors involving in-situ separation of products from the reactants have recently attracted the chemical industries. Reactive distillation involves such a reactor that combines reaction and distillation in a single unit and in-situ product removal. The two major benefits of reactive distillation operation are: higher conversions rates due to shifting the equilibrium to the product side and improved selectivities due to removal of products from the reaction zone. In the paper, “Sensitivity Analysis of Steady-State Methyl Acetate Synthesis Reactive Distillation Column Using Aspen Plus”, the authors, Dipaloy Datta and Dipesh S Patle, have considered the esterification reaction of methanol by acetic acid to form methyl acetate for sensitivity analysis. This reaction was taken up for studies because reaction distillation is a useful method to recover the product from the reactant in the case of equilibrium-limited reactions like esterification and ester hydrolysis. The RADFRAC model from the steady-state simulator Aspen Plus version 20.1 was considered to simulate the process. The steady-state simulated results showed good agreement with the experimental results obtained by Popken et al. Various design variables were considered and optimized to obtain the total conversion of the reactants into product and the better separation of the product.

Molecular biology is centered around synthetic oligonucleotides because nearly every technique in molecular biology like PCR, Real-Time PCR, DNA sequencing, site-directed mutagenesis and Single-Nucleotide Polymorphism (SNP) assays employs chemically synthesized DNAs or RNAs. The oligonucleotide is custom-made according to the specific needs of the individual researcher and purified according to the application for which it is intended. Developments in oligonucleotide applications have spurred dramatic technological advances in oligonucleotide synthesis, purification and quality control. Traditional methods reported for the preparation of nonradio labeled oligonucleotides involving the incorporation of 3' amino functional group(s) are cumbersome and require the incorporation of protected amino group in the polymer support. The paper “An Economical Polymer Support for the Synthesis of 3' Amino Group Containing Oligonucleotides” by Ajay Kumar describes an economical solid phase method for the synthesis of 3'-amino group containing oligonucleotide. This method involves the derivatization of CPG polymer support using 3-bromo-1-(4,4'-dimethoxytrityl)-2-propanol. The oligonucleotide synthesized using this method was characterized by reversed phase FPLC and UV spectroscopy.

In the biological studies of amphibians, accurate age determination of individuals has been one of the most important subjects. Historically, age estimation has long been attempted through the analyses of size frequency distributions of populations or by mark-recapture records of individuals. Recently, however, these classic techniques have been replaced or supplemented by more reliable methods of skeletochronology. Skeletochronology is a method used to determine the age of an individual from bone histology. The method is based on growth lines found in cortical bone. The method assumes that cyclic growth lines in cortical bone are annual, and hence each line in a transverse cross-section of a long bone represents one year of life. The line or thin zone (annulus) consists of avascular tissue and is the amount of bone deposited during the non-growing season (usually winter); the thicker zone is the growth attained during the growing season. In some instances, growth ceases almost completely during the non-growing season, so that the annulus is reduced to a single line called the Line of Arrested Growth (LAG), also known as a Rest Line. The paper, “Age Determination in Common Indian Toad, Bufo melanostictus, by Skeletochronology” by B N Andia, P K Dixit, S Behera and H N Behera analyzes the growth pattern for a complete age series of Bufo melanostictus using skeletochronology.

Decision Support Systems (DSS) support decision-making activities that would be very useful in the comparative evaluation of maintenance strategies. The paper, “Reliability Evaluation and Decision Support System of a Pharmaceutical Plant” by Deepika Garg, Kuldeep Kumar and Jai Singh proposes a method to compute the reliability for a pharmaceutical plant and discusses a DSS for the same. The mathematical model of the unit was developed using Markov birth-death process using a probabilistic approach. The differential equations developed are solved to develop the steady-state availability, and the system performance has been studied for various availability levels for different combinations of failures and repair rates of the subsystems making up the system.

-- Elizabeth Zacharias
Consulting Editor