Aparna Lakshmanan S.,St Xaviers College For Women |
Bujtas C.,University of Pannonia |
Tuza Z.,Hungarian Academy of Sciences
Electronic Journal of Combinatorics | Year: 2015
Putting the concept of line graph in a more general setting, for a positive integer k the k-line graph Lk(G) of a graph G has the Kk-subgraphs of G as its vertices, and two vertices of Lk(G) are adjacent if the corresponding copies of Kk in G share k-1 vertices. Then, 2-line graph is just the line graph in usual sense, whilst 3-line graph is also known as triangle graph. The k-anti-Gallai graph Δk(G) of G is a specified subgraph of Lk(G) in which two vertices are adjacent if the corresponding two Kk-subgraphs are contained in a common Kk+1-subgraph in G. We give a unified characterization for nontrivial connected graphs G and F such that the Cartesian product G□F is a k-line graph. In particular for k = 3, this answers the question of Bagga (2004), yielding the necessary and suficient condition that G is the line graph of a triangle-free graph and F is a complete graph (or vice versa). We show that for any k ≥ 3, the k-line graph of a connected graph G is isomorphic to the line graph of G if and only if G = Kk+2. Furthermore, we prove that the recognition problem of k-line graphs and that of k-anti-Gallai graphs are NP-complete for each k ≥ 3. © 2015, Australian National University. All rights reserved.
Bose L.S.,Amrita University |
Sujatha N.V.,St Xaviers College For Women |
Narayanankutty K.,Amrita University |
Murthy J.,Indian Institute of Astrophysics
Astronomy Letters | Year: 2015
We have used Spitzer observations of galaxies in the ELAIS-N1 region centered at 16h10m01s, +54◦30′36″ to extend the effective sensitivity of GALEX UV observations of the same region. Spitzer is more sensitive to external galaxies than GALEX and we have searched for UV sources at the positions of galaxies in the Spitzer catalog. This has allowed us to extend the sensitivity of the GALEX instrument to 27th magnitude. We have compared the derived number counts of galaxies in the two GALEX bands to standard models of galaxy evolution finding good agreement.The total contribution of these galaxies to the UV background is about 40 photons cm−2 sr−1 s−1 Å−1, in agreement with previous determinations. © 2015, Pleiades Publishing, Inc.
Aneymol V.S.,St Xaviers College For Women |
Williamson M.,Byl Nair Charitable Hospital
International Journal of Pharma and Bio Sciences | Year: 2012
Morbidity and mortality in HIV diseases is due to the occurrence of threatening opportunistic infections. Toxoplasma gondii is a cellular parasite (causative agent of Toxoplasmosis). Toxoplasma has been recognized as an important cause of morbidity and mortality among immunocompromised patients. The present study focuses on the incidence of Toxoplasmosis among HIV seropositive. In the present study T.gondii co-infection was observed in 23% of HIV sero positive patients. 50% female and 57.7% of pediatric group were infected and were statistically significant (p< 0.01). Out of 23 pediatric patients studied for CD4:CD8 ratio, 14 patients were showing significant antibody titer with CD4:CD8 ratio in the range of 0.1- 0.7. The viral load of 14 patients was between 21,600 - 4, 97,429 eq/ml. Out of 14 T.gondii positive patients, 7 patients showed very weak viremia and remaining 7 showed moderate viremia.
Karmaly K.A.,St Xaviers College For Women |
Rabeesh T.P.,St Xaviers College For Women |
Sumesh S.,St Xaviers College For Women
Journal of Entomological Research | Year: 2012
A new species of Cerapachys Smith has been described from Palakkad district, Kerala and its affinities have been discussed with related species.