Volume 14, Issue 2, 2014 April-June

Volume 14, No 2 Pages:
2014 April-June Articles: 6

Pride and prejudice of Indian science awards

There has been a vehement battle (but not bloody brutal) debate on the honorific inference of the most prestigious award in science in India. It is merely a disagreement on trivial conception of whether the award is well known and popularised among the general public. The arguments are strictly based on personal biases. But I won the day–or so I think!

Artificial neural network-based approach for Mizo character recognition system

This paper examines and compares different types of artificial neural networks for recognition of Mizo script. The Mizo script and English script are very similar in nature but special characters – Â, â, Ê, ê, Î, î, Ô, ô, Û, û, Ṭ, and ṭ – are incorporated in Mizo scripts which are not available in English script. In this experiment, an attempt was made to recognize Mizo script including capital letter, small letter, numerals, and special characters. The approach involves processing input images, conversion of image characters into binary matrix, analyzing and mapping the binary matrix, training and testing with a set of desired Mizo characters using different types of neural networks such as back propagation algorithm, radial basis function, learning vector quantization, and recurrent neural network. The results are compared with each other and suggest the best artificial neural networks algorithm for use in the recognition of Mizo script.

Nectar-feeding bat, Cynopterus sphinx pollinate Parkia speciosa flowers and increase fruit production

A study was carried out to establish the relationship between Parkia speciosa (local name Ṭah-lim) and nectar-feeding bat, Cynopterus sphinx with respect to pollination, and effects on fruit production. Eight flowering trees of P. speciosa from Lengteng Wildlife Sanctuary were selected for experimentation. During the flowering season of stink bean from August to November, 2013 visual observations were made twice a week during the night at 18:00 to 05:00 h. C. sphinx visits the capitulum and collects the nectar by landing on the capitulum. Duration of nectar collection by bat is around one second, and then visited the next flower to collect nectar simultaneously. To ascertain the pollination by bats, we captured the bats using mist nets. The yellow cream colour pollen was attached on their facial, neck region, abdomen and wings. This reveals that this bat provides a vital reciprocal service to P. speciosa flowers in terms of pollination. The present study also revealed that seasonality and availability of flowers influenced the frequency of bats. Also compared the average number of fruit production between frequently and randomly visit of P. speciosa trees by bats and observed that frequently visited trees by bats produced more fruits than randomly visited trees (P > 0.05).

Petrochemistry of Bhuban Formation rocks in and around Aizawl City, Mizoram, India

The area in and around Aizawl City is dominated by Middle and Upper Bhuban rock formations. Geologically and petrologically the area has not been so far explored therefore the present study was initiated. The study area is composed of sandstone and shale belonging to Middle and Upper Bhuban formation and lies in between 92°60’ E longitude and 23°58’ N latitude. Rock samples collected from different sections in the study area were analyzed to study the mineralogical compositions of the rocks and determination of the multi-elemental distribution using high precision X- ray fluorescence analysis. The study shows that the area is dominated by different rock units such as sandstone, shale, siltstone and shaly sandstones belonging to middle and upper Bhuban formation. Petrological studies reveal that sandstone is greywacke exhibiting argillaceous matrix mainly siliceous, ferruginous and calcareous (due to presence of fossils) and rock fragments. The oxide and silica weight percentage observed from the geochemical analysis indicate Na2O, K2O and MgO have the maximum variation in the study area. The trace elements Sc, Co, Ni, Cu, Zn, Ga, Pb, Th, Rb, U, Sr, Y, Zr, Nb, Ba, Cr, V in parts per million (ppm) show a different variation in sandstone, shale and siltstone. Ba is having maximum value >500 ppm followed by Zr in sandstone whereas Cr is maximum in shale. Prominent feature is a persistently higher amount of uranium (~4 ppm) in the rocks of Middle Bhuban rocks in contrast to the average abundance in sandstone i.e. 2 ppm.

A mathematical model of glucose-insulin interaction

In this paper, we present a mathematical model of diabetes mellitus, which is a metabolic disease concerned with the regulation process of glucose in the body by the pancreatic insulin. This paper considers the disappearance of glucose due to insulin action (insulin-dependent) as well as the disappearance of glucose due to tissue uptake such as the brain and nerve cells (insulin-independent) and rise in glucose level due to infusion through meal intake, oral glucose intake, continuous nutrition absorption and constant infusion. The linear and non-linear cases are considered and the model is analyzed using Lyapunov’s method. Conditions for local as well as global stability are obtained. Numerical simulations are carried out and graphs are also generated to indicate the role of insulin in the regulation process of glucose in the human body.

Theoretical investigation of electronic and optical properties of zinc blende structure of beryllium sulphide, BeS

A theoretical study of electronic and optical properties of zinc blende structure of BeS is presented by applying the full-potential linearized augmented plane wave (FP-LAPW) method within density-functional theory (DFT) as implemented in WIEN2k code. Our results are in agreement with previous theoretical and experimental studies on this important semiconductor compound. For the optical calculations, the dipole approximation is used. The imaginary part of dielectric function is calculated in momentum representation, which requires matrix elements of the momentum p between occupied and unoccupied states. The microscopic origin of the main features in the optical spectra is identified and also the factors responsible for most of the optical absorption.

Estimation of travel time of P- and S-waves in and around Sylhet and Mat faults in Surma Basin, northeast India

A regional seismicity map for Surma valley and the adjoining region, covering the area bounded by longitudes 90-95°E and latitude 22-26°N was prepared covering the period between 1969-2009 over the generalized tectonic map of the region. The best estimation ofhypocentral parameters form the prime input for the estimation of travel time of P- and S- waves of any region. The Riznichenko diagrams clearly show the change in shape of the travel time versus distance with increasing focal depth, indicative of both a geometrical effect and an increasing P-wave velocity. The Wadati diagrams show systematic decrease in ts/tp, suggesting that the velocity for shear waves increases faster than that for the compressional waves in the upper levels of the crust.