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The radioactivity levels of natural radionuclides 226Ra, 232Th, and 40K in the rocks of Dakshina Kannada region of southern India were measured by NaI (Tl) gamma-ray spectrometer. The specific activities of 226Ra, 232Th, and 40K ranged from 4.2 ± 0.4 to 74.5 ± 1.7 Bq kg−1, 14.5 ± 0.7 to 83.5 ± 1.6 Bq kg−1, and 172 ± 3 to 964 ± 7 Bq kg−1 with the mean of 25.1 ± 1.0 Bq kg−1, 36.1 ± 1.0 Bq kg−1, and 502 ± 5.0 Bq kg−1, respectively. The normality of the frequency distribution curves of 226Ra, 232Th, and 40K was tested using the Kolmogorov–Smirnov test. The radiological hazard indices were computed from the measured activity concentration of natural radionuclides in rocks and these were found to be within acceptable levels. To investigate the sources of radioactivity, the minerals involved in the rocks were detected using XRD and FTIR. The mineralogical studies reveal that the principal sources of gamma radiation in the study area are 232Th-rich phosphates and 40K-bearing feldspars. [ABSTRACT FROM AUTHOR]

Radiological hazards due natural radioactivity in rocks were assessed in the Udupi district on the south west coast of India. The activity of radionuclides 226Ra, 232Th and 40K in rocks, as a commonly used construction material were estimated. The radiological hazards to the population of the region were evaluated. The 232Th activity concentration in granitic rocks was found to be high. To trace the sources of radioactivity in rocks, the mineralogical studies were carried out using XRD and FTIR technique. The studies indicated that the thorium phosphates and potassium bearing feldspars minerals are the main source of radioactivity in rocks. [ABSTRACT FROM AUTHOR]

Carbonaceous meteorites provide clues with regard to prebiotic chemistry and the origin of life. Geological Survey of India recorded a carbonaceous chondrite meteorite fall in Mukundpura, India, on June 6, 2017. We conducted a study to investigate the microbial community that survived the meteorite impact. 16S rRNA metagenomic sequencing indicates the presence of Actinobacteria, Proteobacteria, and Acidobacteria in meteorite impact soil. Comparative phylogenetic analysis revealed an intriguing abundance of class Bacilli in the impact soil. Bacillus thermocopriae IR-1, a moderately thermotolerant organism, was isolated from a rock, impacted by the Mukundpura meteorite. We investigated the resilience of B. thermocopriae IR-1 to environmental stresses and impact shock in a Reddy shock tube. Bacillus thermocopriae IR-1 survived (28.82% survival) the effect of shock waves at a peak shock pressure of 300 kPa, temperature 400 K, and Mach number of 1.47. This investigation presents the first report on the effect of impact shock on B. thermocopriae IR-1. The study is also the first report on studying the microbial diversity and isolation of bacteria from impact crater soil immediately after meteorite impact event. [ABSTRACT FROM AUTHOR]

This essay uses the concept of desire to reinfuse existing conversations about the postcolonial condition and its relationship with globalization. The essay uses the Indian uptake of the seemingly alien cultural practice of rock music to understand the confluence of vestigial structures of colonialism and a globalizing subjectivity that challenge unified notions of a national identity in India. By exploring media coverage of rock and testimony from musicians, the essay unravels the liminal spaces of destabilized identities and fragmented subjectivities that mark the global postcolonial condition. In doing so, it illuminates the role of structures, past and present, in shaping cultural desire and determining affective responses to global culture. [ABSTRACT FROM AUTHOR]

Systematic studies on radiation level and distribution of radionuclides have been carried out in riverine environs of three major rivers of coastal Karnataka, viz. Kali, Sharavathi and Netravathi. The ambient gamma radiation levels along three rivers were measured using a portable plastic scintillometer. Activity concentrations of 226Ra, 232Th and 40K in soil, sediment and rock were measured using a NaI(Tl) gamma-ray spectrometer. In the Kali, Sharavathi and Netravathi riverbanks, the median values of absorbed gamma dose rates in air were found to be 44nGyh−1, 35nGyh−1 and 57nGyh−1, respectively. The highest activity of 226Ra was found in riverbank soil samples of Sharavathi River. The highest activities of 232Th and 40K were found in riverbank soil and sediment samples of Netravathi River. In Kali River, the highest 226Ra activity was recorded for rock samples. To assess the radiological hazard of natural radioactivity in the samples, absorbed gamma dose rates in air, radium equivalent activity, representative level index, external hazard index and internal hazard index associated with the radionuclides were calculated and compared with internationally recommended values. The representative level index (I γr) values are high in sediment samples of Netravathi River. The radium equivalent activity (Raeq), external hazard index (H ex) and internal hazard index (H in) values are high in rock samples of Kali River. The results of these investigations are presented and discussed in this paper. [Copyright &y& Elsevier]

LR-115 plastic track detectors have been used for the measurement of radon exhalation rate and radium concentration in soil and rock samples from Nurpur and its adjoining areas of Kangra district, Himachal Pradesh, India. Uranium concentration is also determined in these samples using fission track technique. The work is undertaken to explore the possibility of uranium prospection and health risk assessments due to uranium and radium in the study area. A positive correlation has been observed between uranium and radon exhalation rate in soil and rocks. [ABSTRACT FROM AUTHOR]

This paper discusses the results of systematic measurement of activity concentrations of 226Ra, 232Th and 40K in riverine samples of river Sharavathi, one of the major rivers of coastal Karnataka in India. Activity concentrations of 226Ra, 232Th and 40K in soil, sediment and rock were measured by Na(I) Tl gamma-ray spectrometry. To assess the radiological hazards of the natural radioactivity in the samples, absorbed gamma-dose rates in air, radium equivalent activity, representative level index, external hazard index and internal hazard index values associated with the radionuclides were calculated and compared with the international recommended values. The representative level index (Igr) values are high in soil and sediment samples. The external hazard index (Hex) and internal hazard index (Hin) values are low in rock samples of the Sharavathi River. [ABSTRACT FROM AUTHOR]