Photometric studies of some starburst galaxies

We present the results of a detailed morphological analysis of ten starburst galaxies selected from the Markarian catalogue of uv-excess objects. CCD surface photometry of these galaxies was carried out based on observations made in B, V (Johnson) and R, I (Kron-Cousins) band passes. We present the radial variations of surface brightness, ellipticity, position angle and the colour indices for each galaxy obtained using ellipse fitting isophotal analysis. The residual images constructed for extracting the fine structure are also presented. A variety of morphological types are found to host the starburst phenomenon. The star formation activity is not confined to the nuclear region alone, but it also occurs at various locations in the galaxy and is seen as clumpy regions. The colour index and the residual images are used for deriving information about the sites of enhanced star formation activity and the triggers of the starburst. The luminosity profiles show an exponential behaviour in the outer region. The disk scale lengths and the half-light radii are derived. The contribution of the burst component has been estimated and the colours of the burst component are presented. Strong isophotal twisting is detected in all the S0 and E galaxies: Mrk 1002, Mrk 1308 and Mrk 14, in the sample. This is accompanied by boxiness in some cases, suggesting that a merger is responsible for the starburst activity in these galaxies. In case of isolated spirals, a bar or a central oval distortion appear to be the likely trigger for the starburst.Comment: 12 pages of text and 28 figures. Uses aastex. To be published in A&A

Impact of Land Use Change on Climate: A Study of Tripura

Land use is the human utilization for money, private, recreational, conservational and administrative purposes. The idea of land use is firmly interwoven with human network advancement. Examples of human turn of events and land use have molded the earth legitimately and internationally since ancient occasions. Current improvement designs, along with highlights of the common habitat and the outcomes of past advancement exercises, decide future advancement openings, and furthermore the requirement for rebuilding or upgrade of natural assets. North-east India is the abode of highly endemic flora and fauna preserving the pristine environment with little human interference until recent times. However, for past two decades a drastic change in the land use pattern in the region has been observed which may threaten the fragile ecological balance of the region. Tripura, known as one of the seven sisters, is a bamboo resource and second largest rubber producer in India. Tripura has the highest number of primate species found in any Indian state. However, as compared to its other sisters, the state is economically backward. The land use of the state is undergoing rapid change which is facilitated to a great extent by rapidly increasing population. The present paper deals with the changing land use of Tripura especially in the last two and a half decades. The objective of the study is to analyse the changing land use of the state in general and changes in agricultural and non-agricultural land use in particular based upon the data collected from secondary sources like Statistical Abstract of Tripura, Population Tables of Census 1991, 2001 and 2011 along with the information collected from various government websites

Production and characterization of pyocyanin pigment from Pseudomonas aeruginosa

Pyocyanin, a blue-green phenazine pigment, is produced by various strains of Pseudomonas aeruginosa and has demonstrated diverse applications in medicine, agriculture, environmental protection, and nanotechnology. This study aimed to isolate and purify pyocyanin pigment from Pseudomonas aeruginosa cultures grown in different media, including succinate, glucose, King’s B, and Muller-Hinton broth. The chloroform extraction method was employed to extract the pigment, resulting in the separation of two layers, with the pyocyanin-enriched pigment residing in the lower blue layer containing chloroform. Subsequently, the pigment was subjected to further purification using column chromatography on a silica gel column, employing chloroform as the elution solvent. The purified pyocyanin was verified by thin-layer chromatography (TLC), ensuring its integrity and purity. The UV-Vis spectrophotometer was then employed to characterize the purified pigments, providing valuable insights into their spectral properties. The results indicate successful isolation and purification of pyocyanin pigment from Pseudomonas aeruginosa cultures in various media, demonstrating the versatility of the extraction method used. The characterization through UV-Vis spectrophotometry confirms the purity of the obtained pigment, validating its potential applicability in a wide range of fields, including medicine, agriculture, environmental management, and nanotechnology for the synthesis of silver nanoparticles. This research contributes to a better understanding of pyocyanin production in Pseudomonas aeruginosa and offers valuable insights into its potential applications, thereby opening new avenues for further exploration and exploitation of this valuable pigment in various industrial and scientific domain