Salem Semmanur Nagara Chettiayar’s Cultural Rituals – Ethnographical Research

In ethnic social life each race has its differences due to the environment in which they live. Some common customs are found in all communities. Transition in cultural life is natural. It is human nature to set each of the transitions in relation to a ritual. Salem Chemmanur Chettiars perform biological rituals during each transition. Human life is characterized by various transitions from birth to death. Rituals and beliefs are found in every community. Putting the sugar water on the baby at birth is seen as a ritual. These rituals are performed according to the developmental stage of the child as he or she grows to a certain size, such as a hemisphere rope around the waist. Such rituals are common among the girl child and some other rituals are performed as she grows up. Women perform the flowering ritual during flowering. Booppu ritual is seen as a defilement ritual. Poop is the first menstrual period. The flower is a sign that the woman has become fertile. This event is considered as an important transformation of life. Like this, wedding ceremonies are considered to be the primary transition ceremony. Death rites are the final event of human life. Various such rituals are observed in the lives of the Chettiars of Salem Semmanur

NGC 7419: A young open cluster with a number of very young intermediate mass pre-MS stars

We present a photometric and spectroscopic study of the young open cluster NGC 7419, which is know to host a large number of classical Be stars for reasons not well understood. Based on CCD photometric observations of 327 stars in UBV passbands, we estimated the cluster parameters as, reddening E(B-V) = 1.65 +/- 0.15 mag and distance = 2900 +/- 400 pc. The turn off age of the cluster was estimated as 25 +/- 5 Myr using isochrone fits. UBV data of the stars were combined with JHK data from 2MASS and were used to create the near infrared (NIR) (J-H) vs (H-K) colour-colour diagram. A large fraction of stars (42%) was found to have NIR excess and their location in the diagram was used to identify them as intermediate mass pre-MS stars. The isochrone fits to pre-MS stars in the optical colour-magnitude diagram showed that the turn-on age of the cluster is 0.3 - 3 Myr. This indicates that there has been a recent episode of star formation in the vicinity of the cluster. Slit-less spectra were used to identify 27 stars which showed H-alpha in emission in the field of the cluster, of which 6 are new identifications. All these stars were found to show NIR excess and located closer to the region populated by Herbig Ae/Be stars in the (J-H) vs (H-K) diagram. Slit spectra of 25 stars were obtained in the region 3700A - 9000A. The spectral features were found to be very similar to those of Herbig Be stars. Those stars were found to be more reddened than the main sequence stars by 0.4 mag on an average. Thus the emission line stars found in this cluster are more similar to the Herbig Be type stars where the circumstellar material is the remnant of the accretion disk.Comment: 20 pages, 11 figures, Accepted for publishing in MNRAS on April 19, 200

Contraction and domination in fuzzy graphs

Fuzzy sets and logics is a true crowning achievement of the century. Among the variety of exemplary changes in science and technology, the concept of uncertainty played a significant role, which led to the development of fuzzy sets, which in turn helped in the transition from graph theory to fuzzy graph theory. This paper familiarizes an improved concept in fuzzy graphs, called contraction. Two types of contraction namely edge contraction and neighbourhood contraction are introduced. We developed these two concepts in fuzzy graphs and analyse its effect on domination number and edge domination number. Any research is meaningful only by its contribution to the society. The modern world and the field of networks are inseparable. We have applied our concept to a wired network problem.Publisher's Versio

The AGN and Gas Disk in the Low Surface Brightness Galaxy PGC045080

We present radio observations and optical spectroscopy of the giant low surface brightness (LSB) galaxy PGC 045080 (or 1300+0144). PGC 045080 is a moderately distant galaxy having a highly inclined optical disk and massive HI gas content. Radio continuum observations of the galaxy were carried out at 320 MHz, 610 MHz and 1.4 GHz. Continuum emission was detected and mapped in the galaxy. The emission appears extended over the inner disk at all three frequencies. At 1.4 GHz and 610 MHz it appears to have two distinct lobes. We also did optical spectroscopy of the galaxy nucleus; the spectrum did not show any strong emission lines associated with AGN activity but the presence of a weak AGN cannot be ruled out. Furthermore, comparison of the H$\alpha$ flux and radio continuum at 1.4 GHz suggests that a significant fraction of the emission is non-thermal in nature. Hence we conclude that a weak or hidden AGN may be present in PGC 045080. The extended radio emission represents lobes/jets from the AGN. These observations show that although LSB galaxies are metal poor and have very little star formation, their centers can host significant AGN activity. We also mapped the HI gas disk and velocity field in PGC 045080. The HI disk extends well beyond the optical disk and appears warped. In the HI intensity maps, the disk appears distinctly lopsided. The velocity field is disturbed on the lopsided side of the disk but is fairly uniform in the other half. We derived the HI rotation curve for the galaxy from the velocity field. The rotation curve has a flat rotation speed of ~ 190 km/s.Comment: Paper contains 14 figures and 4 tables. Figures 8, 10 (color) and 13 supplied separately. Accepted for publication in MNRA

Ethnomedicinal Perspectives of Botanicals used by Malayali Tribes in Vattal Hills of Dharmapuri (TN), India

An ethnobotanical survey was conducted to collect information about the medicinal plants used by Malayali tribes in Dharmapuri district Tamilnadu, India. Informations presented here were gathered from Malayali tribes using an integrated approach of botanical collections and interview schedules. A total of 7 informants were interviewed and 27 ethno medicinal plant species distributed in 16 families have been documented. Medicinal plants used by Malayali tribes have been listed along with plant parts used with its medicinal significance. For most of the ailments fresh plant materials were invariably used. Further, it could be inferred that plants were most commonly used to cure skin diseases, poison bites, stomachache and nervous disorders. Collected information depicts that Malayali tribes largely depend on medicinal plants to meet their primary health care needs