Satellite-based study of physico-optical properties of aerosols over a westernmost location of Brahmaputra valley

This study examines the long term trend of the radiatively active atmospheric aerosols which can influence the Earth’s energy budget directly by scattering and absorbing radiation and indirectly by acting as cloud condensation nuclei. MODIS sensor on board the NASA Earth Observing System Terra and Aqua satellite based Aerosol Optical Depth (AOD) data are used for long term analysis of aerosols over Bongaigaon, Assam for the period August, 2002 to March, 2017. Highest AOD values are observed in pre-monsoon (March-May) season due to long range transportation as well as intense biomass burning activities especially as a part of Jhum cultivation. In general, AOD values are low in post-monsoon (October-November) season which may be due to wash out of aerosols by rain in the preceding months without enough replacement. The monthly AOD values vary from its highest value 0.949 in April, 2016 to its lowest value 0.107 in November, 2002 for the study period. From the comparison of MODIS Terra and Aqua AOD at 550 nm, it is clearly seen that generally Terra AOD at 10:30 hr is higher than the Aqua AOD at 13:30hr. A slowly increasing trend of both Aqua and Terra AOD at 550 nm is observed over the study location. The observed Ångström exponent value varies from its minimum value in monsoon season to its maximum value in winter season. With increasing AOD values, horizontal visibility decreases over Bongaigaon

Dynamics of Hot QCD Matter -- Current Status and Developments

The discovery and characterization of hot and dense QCD matter, known as Quark Gluon Plasma (QGP), remains the most international collaborative effort and synergy between theorists and experimentalists in modern nuclear physics to date. The experimentalists around the world not only collect an unprecedented amount of data in heavy-ion collisions, at Relativistic Heavy Ion Collider (RHIC), at Brookhaven National Laboratory (BNL) in New York, USA, and the Large Hadron Collider (LHC), at CERN in Geneva, Switzerland but also analyze these data to unravel the mystery of this new phase of matter that filled a few microseconds old universe, just after the Big Bang. In the meantime, advancements in theoretical works and computing capability extend our wisdom about the hot-dense QCD matter and its dynamics through mathematical equations. The exchange of ideas between experimentalists and theoreticians is crucial for the progress of our knowledge. The motivation of this first conference named "HOT QCD Matter 2022" is to bring the community together to have a discourse on this topic. In this article, there are 36 sections discussing various topics in the field of relativistic heavy-ion collisions and related phenomena that cover a snapshot of the current experimental observations and theoretical progress. This article begins with the theoretical overview of relativistic spin-hydrodynamics in the presence of the external magnetic field, followed by the Lattice QCD results on heavy quarks in QGP, and finally, it ends with an overview of experiment results.Comment: Compilation of the contributions (148 pages) as presented in the `Hot QCD Matter 2022 conference', held from May 12 to 14, 2022, jointly organized by IIT Goa & Goa University, Goa, Indi

Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC

Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe

Production of Extracellular Polymeric Substances by Halophilic Bacteria of Solar Salterns

Moderately halophilic aerobic bacteria were isolated from 31 soil and 18 water samples collected from multipond solar salterns of Gujarat, Orissa, and West Bengal, India. A total of 587 bacterial isolates with distinct morphological features were obtained from these samples following dilution and plating on MH agar medium supplemented with NaCl. The isolates were screened for growth associated extracellular polymeric substances (EPS) production in MY medium under batch culture. In all, 20 isolates were selected as potent ones producing more than 1 g/L of EPS. These EPS producing isolates were characterized in detail for their morphological, physiological, and biochemical features and tentatively identified as members belonging to the genera Halomonas, Salinicoccus, Bacillus, Aidingimonas, Alteromonas, and Chromohalobacter. Apart from EPS production, these isolates also hold promise towards the production of various biomolecules of industrial importance

Short term introduction of pollutants into the atmosphere at a location in the Brahmaputra Basin: A case study

AbstractIntensive fire ignition and cracker work activities takes place during the festival of light called Diwali in India, celebrated for a period of few days in the month of October or November every year. The firecracker releases several pollutants [such as particulate matter (PM), black carbon (BC), organics, trace gases] near the surface. The effect of firecrackers on the atmospheric constituents is evaluated over Dibrugarh by monitoring the concentrations of PM, PM10 (particle radius ≤10 µm), PM2.5 (particle radius ≤2.5 µm) and BC during the Diwali and post-Diwali days (5 days after the Diwali Festival) in the years 2009 and 2010. Monthly average concentrations of each species except for the Diwali and post Diwali days is considered as the background concentrations. The concentration levels of the pollutants as recorded on the Diwali days are found to be a number of times higher (5.33 and 2.50 times for PM10, 5.74 and 2.65 times for PM2.5, 1.21 and 1.66 times for BC for the year 2009 and 2010, respectively) than the background levels at the peak hours of the fire work activity. To delineate the contribution of fireworks to the high concentrations of the species we performed air mass back trajectory analysis using the NOAA–HYSPLIT model in order to examine the existence of the transported aerosols. The ten day accumulated MODIS fire maps are also analyzed to mark out the contribution of aerosols from biomass burning. These analyses reveal that the higher concentrations of near surface aerosols including BC during the festival is due to the local effect of firework activities, neither because of long–range transport nor due to biomass burning activities. However, the higher concentration of pollutants for short periods has not degraded air quality substantially to cause health risks to people exposed to the festival in this environment

Partial characterization of an extracellular polysaccharide produced by the moderately halophilic bacterium <i>Halomonas xianhensis</i> SUR308

<div><p>A moderately halophilic bacterium, <i>Halomonas xianhensis</i> SUR308 (Genbank Accession No. KJ933394) was isolated from a multi-pond solar saltern at Surala, Ganjam district, Odisha, India. The isolate produced a significant amount (7.87 g l⁻¹) of extracellular polysaccharides (EPS) when grown in malt extract–yeast extract medium supplemented with 2.5% NaCl, 0.5% casein hydrolysate and 3% glucose. The EPS was isolated and purified following the conventional method of precipitation and dialysis. Chromatographic analysis (paper, GC and GC-MS) of the hydrolyzed EPS confirmed its heteropolymeric nature and showed that it is composed mainly of glucose (45.74 mol%), galactose (33.67 mol %) and mannose (17.83 mol%). Fourier-transform infrared spectroscopy indicated the presence of methylene and carboxyl groups as characteristic functional groups. In addition, its proton nuclear magnetic resonance spectrum revealed functional groups specific for extracellular polysaccharides. X-ray diffraction analysis revealed the amorphous nature (CI_xrd, 0.56) of the EPS. It was thermostable up to 250°C and displayed pseudoplastic rheology and remarkable stability against pH and salts. These unique properties of the EPS produced by <i>H. xianhensis</i> indicate its potential to act as an agent for detoxification, emulsification and diverse biological activities.</p></div

Seasonal Migration, Social Change and Migrants? Rights: Lessons from West Bengal

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Seasonal Migration and Welfare/Illfare in Eastern India: A Social Analysis

Over 500,000 people are regularly engaged in seasonal migration for rice work into southern West Bengal. This paper analyses social processes at work in the interactions between employers and workers, and the welfare/illfare outcomes. Group identities based on religion and ethnicity are strengthened through the experience of migration and deployed by some migrants to make this form of employment less degrading. In West Bengal seasonal migration can involve practical welfare gains. Importantly, an informal wage floor has been put into place and managed by the peasant union allied to the largest party in the Left Front regime. However, the costs and risks of migration remain high

Seasonal migration, employer-worker interactions, and shifting ethnic identities in contemporary West Bengal

This article tells of changing social and spatial identities in the countryside of con temporary West Bengal. It draws on a study of interactions between those seeking wage work in agriculture and the people trying to recruit them. We find a continuing and nested process of both self-identification and categorisation. Unconscious as well as conscious ethnic affinities are consolidated and changed. At the same time, identities are used instrumentally by workers to make the outcome of negotiations less demeaning, and by employers to bargain more effectivelyfor the workforce they need. The context is one of the emergence of capitalist production relations in agriculture, presided over by a coalition government led by the Communist Party of India (Marxist). The newly pros perous agriculture has been a source of wealth for capitalist employers, reinforcing constructions of difference in relation to the migrant workers they employ. At the same time, many employers are attracted by the prospects of urban,jobs and life-styles and invest in their children's education. Migrant workers show a similar ambivalence, being attracted by the potential earnings and consumption possibilities arising out of being employed in the West Bengal 'rice bowl', and simultaneously repelled by the dangers they associate with the place