The Nuclear Activity of the Galaxies in the Hickson Compact Groups

In order to investigate the nuclear activity of galaxies residing in compact groups of galaxies, we present results of our optical spectroscopic program made at Okayama Astrophysical Observatory. We have performed optical spectroscopy of 69 galaxies which belong to 31 Hickson Compact Groups (HCGs) of Galaxies. Among them, three galaxies have discordant redshifts. Further, spectral quality is too poor to classify other three galaxies. Therefore, we describe our results for the remaining 63 galaxies. Our main results are summarized below. (1) We have found in our sample; 28 AGN, 16 HII nuclei, and 19 normal galaxies which show no emission line. We used this HCG sample for statistical analyses. (2) Comparing the frequency distributions of activity types between the HCGs and the field galaxies whose data are taken from Ho, Filippenko, & Sargent (382 field galaxies), we find that the frequency of HII nuclei in the HCGs is significantly less than that in the field. However, this difference may be due to selection bias that our HCG sample contains more early-type galaxies than the field, because it is known that HII nuclei are rarer in early-type galaxies than in later ones. (3) Applying correction this morphological bias to the HCG sample, we find that there is no statistically significant difference in the frequency of occurrence of emission-line galaxies between the HCGs and the field. This implies that the dense galaxy environment in the HCGs does not affect triggering both the AGN activity and the nuclear starburst. We discuss some implications on the nuclear activity in the HCG galaxies.Comment: 33 pages (3 aasms4 LaTeX files), 5 figures (5 Postscript files: excluded Figure 1), Accepted for publication in The Astronomical Journa

Equitable and outdegree equitable domination number of graphs

Let G = (V, E) be a simple graph. A subset D of V is said to be a dominating set of G, if each vertex in V is either in D or has a neighbour in D. A subset D of V is said to be an equitable dominating set of G, if for every v ∈ V − D, there exists a vertex u ∈ D such that uv ∈ E(G) and |deg(u) − deg(v)| ≤ 1. The minimum cardinality of an equitable dominating set of G, denoted by γᵉ(G), is called the equitable domination number of G. The edges from a vertex u ∈ D to V − D are called the dominating edges of u from D. A dominating set D is called an outdegree equitable dominating set if the difference between the cardinalities of the sets of dominating edges from any two points of D is atmost one. The minimum cardinality of an outdegree equitable dominating set of G, denoted by γoe(G) is called the outdegree equitable domination number of G. In this paper we study equitable domination number and outdegree equitable domination number of some graphs.Publisher's Versio

Impact of coastal bottom trawling on target and non- target resources along the south west coast of India

The trawling is carried out almost throughout the year in the inshore water except for peak monsoon months. Their nonoperation is chiefly due to the unfavourable sea conditions or bans imposed by the governments as in Kerala, Tamilnadu, Andhra Pradesh or socially self-imposed ban as in Karnataka. The excessive fishing pressure exerted by the mechanized / motorized sector in a climatically limited coastal habitat up to a depth of about 50 m have not only affected the sustenance of some easily vulnerable resources, but also challenged the very existence of some shell fishes, fin fishes and bottom organisms, including the biota which are non-edible to man but vital in the food web of all exploitable resources. The present account pertains to the impact of the gear along the south-west coast (Karnataka and Kerala) trawling grounds preferably on the non- target by catch

Redshift dependence of the low-frequency turnover of quasars

I have identified a sample of quasars whose spectra exhibit clearly defined maxima at low frequencies. The turnover frequencies are found to increase with redshift, but the equipartition angular sizes, deduced on the assumption of a synchrotron self-absorption model, decrease much faster than is predicted by any simple cosmological model. I show that this variation may be due to the steep density gradient of the gas in the nuclear regions of the parent galaxies and to the increase in number density or luminosity of the sources at earlier epochs

Study on the induced maturation of the Indian pearl oyster Pinctada fucata (Gould) at Tuticorin, Tamil Nadu, India

In the induced maturation experiments of the pearl oyster Pinctada fucata (Gould), 7.5 ± 3.54%, 6.67% and 15 ± 7.07% fully mature pearl oysters were obtained on day 43, 42 and 36 in oysters fed with mixed algae (T-1), mixed algae and raw corn flour (T-2), mixed algae and raw rice flour (T-3), respectively under laboratory conditions. Among the treatments, it was observed that the (T-3) mixed algae with raw rice flour gave the best results with pearl oysters maturing 62.5 ± 7.08% under laboratory conditions on day 29 itself. Whereas, 35 % ± 7.07 % of fully mature pearl oysters were obtained on the 15th day and 36th day from the farm and laboratory, respectively and none in the non fed. Of the matured animals, 43.33% of stage III animals fed on mixed algae changed to stage IV within 19 days, while gonad of 40 ± 14.14% of pearl oysters without feeding changed to stage IV within 26 days under laboratory conditions. Maturity of 53.12 ± 11.97% pearl oysters did not change when maintained in the farm conditions within 24 days

High-frequency structure of Ooty occultation sources. I Sources with central components

The NRAO three-element interferometer operating simultaneously at 2695 and 8085 MHz has been used to study 39 Ooty occultation sources which have been found to be double at 327 MHz. This paper reports on the comparison of the high- and low-frequency structures of five out of nine of the above sources which show an additional central component at the high frequencies. The spectral indices (below 10 GHz) of the central components vary from positive, nearly zero to negative values as high as -0.65. The indices of the extended components are all steeper than about -0.9. Two of the sources are also shown to have compact subcomponents within the extended components. The fraction of the total flux density within the central components of the present sample of 39 weak sources appears to be higher than among the brighter sample of 3C sources

The Irreducible String and an Infinity of Additional Constants of Motion in a Deposition-Evaporation Model on a Line

We study a model of stochastic deposition-evaporation with recombination, of three species of dimers on a line. This model is a generalization of the model recently introduced by Barma {\it et. al.} (1993 {\it Phys. Rev. Lett.} {\bf 70} 1033) to $q\ge 3$ states per site. It has an infinite number of constants of motion, in addition to the infinity of conservation laws of the original model which are encoded as the conservation of the irreducible string. We determine the number of dynamically disconnected sectors and their sizes in this model exactly. Using the additional symmetry we construct a class of exact eigenvectors of the stochastic matrix. The autocorrelation function decays with different powers of $t$ in different sectors. We find that the spatial correlation function has an algebraic decay with exponent 3/2, in the sector corresponding to the initial state in which all sites are in the same state. The dynamical exponent is nontrivial in this sector, and we estimate it numerically by exact diagonalization of the stochastic matrix for small sizes. We find that in this case $z=2.39\pm0.05$.Comment: Some minor errors in the first version has been correcte

Improvements in Refractory Practices in Reheating furnaces in Tisco

The rated capacity of the authors' plant is two million tonnes of ingot all of which are processed through the primary and finishing mills. Various products manufactured in these mills are- blooms, slabs, billets, rails, heavy and light structurals, wheels, tyres, axles, plates, sheets, merchant mill products, etc. In spite of the fact that the plant is more than 70 years old, the finished products produced are over 100% capacity for the past four years

Domestic fish marketing in India - changing structure, conduct, performance and policies

This study has been conducted in all the major coastal states and some selected inland states to understand the domestic marketing of fish in India. The total marketing costs of auctioneer, wholesaler, retailer, vendor, marine fishermen cooperative society and contractor/freshwater fishermen cooperative society have been found to be Re 0.98, Rs 8.89, Rs 6.61, Rs 4.50, Rs 6.00 and Rs 3.51, respectively. The marketing efficiencies for Indian major carps (IMC), sardine and seer fish have been found to vary from 34 per cent to 74 per cent, depending on the length of market channel. The marketing efficiency has been found more in the case of marine species than freshwater species, since the latter travel longer distances from the point of production to consumption centre, passing many intermediaries as compared to the former. The fisherman’s share in consumer’s rupee has shown variations across species, marketing channels and markets. The infrastructure facilities at most of the surveyed landing centres, fishing harbours and wholesale and retail markets have been found grossly inadequate and poorly maintained. The study has highlighted the need for formulating a uniform market policy for fishes for easy operation and regulation so that the country’s fish production is efficiently managed and delivered to the consuming population, ensuring at the same time remunerative prices to the fishers.Marketing,