Assessment of NORMs (238U, 232Th, 40K) and radiation hazard indices in Beldih apatite mine region of Purulia district, West Bengal, India.

The radiation arising from naturally occurring radioactive materials (NORMs) is the foremost contributor to the collective dose received by the global population. The present study aims to measure the natural background radiation level and the associated gamma radiation dose in air in the Beldih apatite mine region of Purulia district, India. This study is primarily focused on the determination of 238U, 232Th and 40K activities in the sub-surface soil of the study area. The measurements were carried out using a High Purity Germanium (HPGe) detector-based gamma-ray spectrometer with a relative efficiency of 80%. To achieve uniformity in exposure estimations, radium equivalent activity has been calculated. Additionally, the internal hazard index, external hazard index, radioactivity level index and gamma dose rates have been evaluated to estimate the radiation hazard levels in the study area. The comparison of obtained concentrations and hazard indices with global data (UNSCEAR. (2008). Sources, effects and risks of ionizing radiation. United nations scientific committee on the effects of atomic radiation (report to the general assembly, with Annexes).) suggests that this region lies in a relatively high background radiation zone.

Estimation of gross α-ß and tritium activities in groundwater samples using LSC-TDCR technique in and around the geothermal region of Eastern India.

The present study is an attempt to assess the radiogenic quality of groundwater on the basis of gross α, gross ß and tritium (3H or H-3) activities in the Bakreswar-Tantloi geothermal region of Chotanagpur Plateau, West Bengal and Jharkhand, India. The aforesaid parameters in groundwater samples were measured using liquid scintillation counting triple to double coincidence ratio (LSC-TDCR) technique. Groundwater samples collected from Bakreswar-Tantloi geothermal region show gross α activities from below the minimum detectable activity (BMDA) to 0.5 ± 0.05 Bq/L, gross ß activities from BMDA to 0.2 ± 0.01 Bq/L and H-3 activities from BMDA to 63.42 Bq/L. The average gross α, gross ß and H-3 activities are also within the permissible limits prescribed by the World Health Organization (WHO). Though the annual effective doses in some samples were higher than the reference dose level of 0.1 mSv, the overall result suggests that the groundwater in the Bakreswar-Tantloi geothermal region is radiologically safe considering the radionuclides covered in this study.

Liquid-liquid extraction of No-carrier-added 129Cs with various extractants.

Two different iodide targets, BiI3 and KI were irradiated by α-particles to produce 129Cs via 127I(α, 2n)129Cs reaction. 129Cs was separated from bulk Bi (when BiI3 was used as target) by anion exchanger TOA dissolved in cyclohexane. Irradiation of KI with alpha particle produced 129Cs along with minute amount 44mSc. 44mSc was successfully separated from 129Cs using 18-crown 6 ether dissolved in nitrobenzene.

Copper dependent ERK1/2 phosphorylation is essential for the viability of neurons and not glia.

Intracellular copper [Cu(I)] has been hypothesized to play role in the differentiation of the neurons. This necessitates understanding the role of Cu(I) not only in the neurons but also in the glia considering their anatomical proximity, contribution towards ion homeostasis, and neurodegeneration. In this study, we did a systematic investigation of the changes in the cellular copper homeostasis during neuronal and glial differentiation and the pathways triggered by them. Our study demonstrates increased mRNA for the plasma membrane copper transporter CTR1 leading to increased Cu(I) during the neuronal (PC-12) differentiation. ATP7A is retained in the trans-Golgi network (TGN) despite high Cu(I) demonstrating its utilization towards the neuronal differentiation. Intracellular copper triggers pathways essential for neurite generation and ERK1/2 activation during the neuronal differentiation. ERK1/2 activation also accompanies the differentiation of the foetal brain derived neuronal progenitor cells. The study demonstrates that ERK1/2 phosphorylation is essential for the viability of the neurons. In contrast, differentiated C-6 (glia) cells contain low intracellular copper and significant downregulation of the ERK1/2 phosphorylation demonstrating that ERK1/2 activation does not regulate the viability of the glia. But ATP7A shows vesicular localization despite low copper in the glia. In addition to the TGN, ATP7A localizes into RAB11 positive recycling endosomes in the glial neurites. Our study demonstrates the role of copper dependent ERK1/2 phosphorylation in the neuronal viability. Whereas glial differentiation largely involves sequestration of Cu(I) into the endosomes potentially (i) for ready release and (ii) rendering cytosolic copper unavailable for pathways like the ERK1/2 activation.

Studies on radiation stability of natural caffeine.

Behavior of isolated caffeine in 60Co- γ radiation environment was studied in solid form as well as in aqueous medium. No degradation in solid caffeine structure was observed after exposing up to a dose of 10 kGy. In aqueous medium, 98% radiolytic degradation of caffeine was observed after application of 1.26 kGy γ dose. Radiation chemical yield decreased with increasing dose. The degradation was mostly favored in neutral medium. Addition of ethanol decreased the radiolytic degradation efficiency.

Differentiating Wild and Apiary Honey by Elemental Profiling: a Case Study from Mangroves of Indian Sundarban.

Honey is a natural substance produced by honeybees from the nectar or secretion of flowering plants. Along with the botanical and geographical origin, several environmental factors also play a major role in determining the characteristics of honey. The aim of this study is to determine and compare the elemental concentration of various macro and trace elements in apiary and wild honeys collected from different parts of Indian Sundarbans. The elemental analysis was performed in inductively coupled plasma optical emission spectroscopy preceded by microwave digestion method. The concentrations of 19 elements (Ag, Al, As, B, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Pb, Se and Zn) were investigated from thirteen locations of Indian Sundarbans. This comparative study shows in wild honey samples, the concentration of K was highest followed by Ca, Mg and Na and Zn was lowest among all. In contrast, in apiary honey samples, Ca had maximum concentration followed by K, Mg and Na and Ag had minimum among all. The elemental concentration in honey from apiary was either equal or higher than their wild counterpart. The results of the factor analysis of PCA algorithm for wild and apiary honey samples were highly variable which implies that the elements are not coming from the same origin. The concentration of element was found to be highly variable across sites and across sources of honey samples.

Separation of 71,72As from alpha particle induced gallium oxide target by solid cation and anion exchangers, DOWEX-50 and DOWEX-1.

46.0 MeV alpha particle induced reaction on gallium oxide target results production of no-carrier-added (NCA) 71,72As and 67Ga tracer. 71,72As were separated from the target matrix by solid liquid extraction (SLX) using two different exchangers, Dowex-1 and Dowex-50. At best condition of 0.2 g Dowex-1 + 6 M HCl and 0.2 g Dowex-50 + 10-3 M HCl bulk gallium was completely extracted leaving behind NCA 71,72As in the aqueous phase. Dowex-50 was found to be more suitable and offered high separation factor, 3.2 × 105.

Theranostic Terbium Radioisotopes: Challenges in Production for Clinical Application.

Currently, research on terbium has gained a momentum owing to its four short-lived radioisotopes, 149Tb, 152Tb, 155Tb, and 161Tb, all of which can be considered in one or another field of nuclear medicine. The members of this emerging quadruplet family have appealing nuclear characteristics and have the potential to do justice to the proposed theory of theranostics nuclear medicine, which amalgamates therapeutic and diagnostic radioisotopes together. The main challenge for in vivo use of these radioisotopes is to produce them in sufficient quantity. This review discusses that, at present, neither light charged particle nor the heavy ion (HI) activation are suitable for large-scale production of neutron deficient terbium nuclides. Three technological factors like (i) enrichment of stable isotopes to a considerable level, (ii) non-availability of higher energies in commercial cyclotrons, and (iii) non-availability of the isotope separation technique coupled with commercial accelerators limit the large scale production of terbium radionuclides by light charged particle activation. If in future, the technology can overcome these hurdles, then the light charged particle activation of enriched targets would produce a high amount of useful terbium radionuclides. On the other hand, to date, the spallation reaction coupled with an online isotope separator has been found suitable for such a requirement, which has been adopted by the CERN MEDICIS programme. The therapeutic 161Tb radionuclide can be produced in a reactor by neutron bombardment on enriched 160Gd target to produce 161Gd which subsequently decays to 161Tb. The radiochemical separation is mandatory even if the ISOL technique is used to obtain high radioisotopic purity of the desired radioisotope.

Separation of 206Po from alpha particle irradiated lead bismuth eutectic target.

Lead bismuth eutectic (LBE) target was bombarded with 46 MeV α-particle. Possibility of separation of no-carrier-added (NCA) polonium radioisotopes from the bulk lead-bismuth eutectic target was explored. Differential precipitation showed presence of Po with bulk Bi, leaving behind bulk Pb in aqueous medium. NCA 206Po radioisotope was then separated from bulk Bi using trioctylamine (TOA) as the extractant. At best condition of 0.01 M TOA+0.1 M HCl, highest separation factor (>500) was achieved between NCA Po and bulk Bi.

Interaction of metal oxide nanoparticles with microplastics: Impact of weathering under riverine conditions.

The ubiquitous distribution of microplastics (MPs) leads to inevitable interactions with the toxic pollutants present in the environment including metal-oxide nanoparticles. This study investigates the interaction of CeO2 nanoparticles (CeNPs) with MPs generated from a disposable plastic container. Further, rough MPs (R-MPs), generated through mechanical abrasion of MPs with sand, were used to probe the impact of roughness. To understand the sorption kinetics and underlying interaction processes, batch experiments were carried out. The results distinctly indicate that CeNPs sorption occurred on MPs surfaces and was consistent with the pseudo-second order kinetics model. For pristine MPs, the sorption capacity was as high as 12.9 mg/g while for R-MPs kinetic equilibrium was achieved faster and an enhanced sorption capacity (13.4 mg/g) was identified. A rise in sorption with an increase in salinity was noted while pH and humic acid exhibited a negative correlation. The observed interactions were attributed to the aggregation profile and surface charge of CeNPs and MPs. Surprisingly, CeNPs also got loaded onto MPs in non-agitated and undisturbed conditions. The sorption process was influenced by the type of aqueous matrix and the sorption capacity at equilibrium followed the trend: distilled water> synthetic freshwater> river water. FTIR spectra, zeta potential, SEM imaging, and elemental mapping revealed electrostatic interaction as the dominant mechanism. This work contributes towards the knowledge gap on the environmental risk of MPs.

Fabrication of thiophene-chitosan hydrogel-trap for efficient immobilization of mercury (II) from aqueous environs.

The fabrication of thiophene-chitosan (TCS) hydrogel has been carried out to show the excellent binding performance of Hg(II) from an aqueous solution of heavy metal ions in presence of thiophene moiety within the hydrogel network. Thiophene moiety has been implanted within chitosan, a wild bio-resources, through a facile Schiff base condensation strategy with 2-thiophenecarboxaldehyde to develop a three-dimensional network of TCS hydrogel. The parameters influencing adsorption capacity such as pH, volume of functional agent, contact time, amount of the hydrogel are included to broaden the in-depth study for the adsorption window of Hg(II) followed by the desorption and reusability performance of TCS. The results indicate that the TCS hydrogel for Hg(II) followed pseudo-second-order kinetics. Ethylenediaminetetraacetic acid (EDTA), acts as a better eluent compared to HCl to desorb Hg(II) and even after recurring adsorption/desorption cycles, removal efficacy of TCS hydrogel could be retained.

Retromer retrieves the Wilson disease protein ATP7B from endolysosomes in a copper-dependent manner.

The Wilson disease protein, ATP7B maintains copper (herein referring to the Cu+ ion) homeostasis in the liver. ATP7B traffics from trans-Golgi network to endolysosomes to export excess copper. Regulation of ATP7B trafficking to and from endolysosomes is not well understood. We investigated the fate of ATP7B after copper export. At high copper levels, ATP7B traffics primarily to acidic, active hydrolase (cathepsin-B)-positive endolysosomes and, upon subsequent copper chelation, returns to the trans-Golgi network (TGN). At high copper, ATP7B colocalizes with endolysosomal markers and with a core member of retromer complex, VPS35. Knocking down VPS35 did not abrogate the copper export function of ATP7B or its copper-responsive anterograde trafficking to vesicles; rather upon subsequent copper chelation, ATP7B failed to relocalize to the TGN, which was rescued by overexpressing wild-type VPS35. Overexpressing mutants of the retromer complex-associated proteins Rab7A and COMMD1 yielded a similar non-recycling phenotype of ATP7B. At high copper, VPS35 and ATP7B are juxtaposed on the same endolysosome and form a large complex that is stabilized by in vivo photoamino acid labeling and UV-crosslinking. We demonstrate that retromer regulates endolysosome to TGN trafficking of copper transporter ATP7B in a manner that is dependent upon intracellular copper.

Radiogenic quality assessment of ground and riverine water samples collected from Indian Sundarbans.

The present study attempts to generate the first baseline data on gross α and ß activities in groundwater and riverine water samples collected from different regions of Indian Sundarbans, a part of the world's largest mangrove ecosystem. Until the present, no information is available related to radioactivity measurement in water samples from this vast area. Gross alpha-beta activities were measured by liquid scintillation counting-triple to double coincidence ratio (LSC-TDCR) technique. The minimum detectable activities in present experimental condition were found to be 21 mBq L-1 and 55 mBq L-1 for gross α and ß respectively. Gross alpha activities in all groundwater and riverine samples were found to be below the detection limit (BDL), whereas gross beta activities in groundwater and riverine samples varied from BDL to 0.46 ± 0.24 Bq L-1 and BDL to 0.90 ± 0.26 Bq L-1 respectively, which are below WHO recommended value 1 Bq L-1. Annual effective doses were below 0.1 mSv. U and Th concentrations in the water samples were determined by ultrasonic-nebulizer assisted Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and found to be BDL. For assessing 3H activity, double-distilled water samples were measured by LSC-TDCR technique, which provided BDL result.

A Tripartite Interaction among the Basidiomycete Rhodotorula mucilaginosa, N2-Fixing Endobacteria, and Rice Improves Plant Nitrogen Nutrition.

Nitrogen (N) limits crop yield, and improvement of N nutrition remains a key goal for crop research; one approach to improve N nutrition is identifying plant-interacting, N2-fixing microbes. Rhodotorula mucilaginosa JGTA-S1 is a basidiomycetous yeast endophyte of narrowleaf cattail (Typha angustifolia). JGTA-S1 could not convert nitrate or nitrite to ammonium but harbors diazotrophic (N2-fixing) endobacteria (Pseudomonas stutzeri) that allow JGTA-S1 to fix N2 and grow in a N-free environment; moreover, P. stutzeri dinitrogen reductase was transcribed in JGTA-S1 even under adequate N. Endobacteria-deficient JGTA-S1 had reduced fitness, which was restored by reintroducing P. stutzeri JGTA-S1 colonizes rice (Oryza sativa), significantly improving its growth, N content, and relative N-use efficiency. Endofungal P. stutzeri plays a significant role in increasing the biomass and ammonium content of rice treated with JGTA-S1; also, JGTA-S1 has better N2-fixing ability than free-living P. stutzeri and provides fixed N to the plant. Genes involved in N metabolism, N transporters, and NODULE INCEPTION-like transcription factors were upregulated in rice roots within 24 h of JGTA-S1 treatment. In association with rice, JGTA-S1 has a filamentous phase and P. stutzeri only penetrated filamentous JGTA-S1. Together, these results demonstrate an interkingdom interaction that improves rice N nutrition.

Author Correction: An Endophytic Bacterial Consortium modulates multiple strategies to improve Arsenic Phytoremediation Efficacy in Solanum nigrum.

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An Endophytic Bacterial Consortium modulates multiple strategies to improve Arsenic Phytoremediation Efficacy in Solanum nigrum.

Endophytic microbes isolated from plants growing in contaminated habitats possess specialized properties that help their host detoxify the contaminant/s. The possibility of using microbe-assisted phytoremediation for the clean-up of Arsenic (As) contaminated soils of the Ganga-Brahmaputra delta of India, was explored using As-tolerant endophytic microbes from an As-tolerant plant Lantana camara collected from the contaminated site and an intermediate As-accumulator plant Solanum nigrum. Endophytes from L. camara established within S. nigrum as a surrogate host. The microbes most effectively improved plant growth besides increasing bioaccumulation and root-to-shoot transport of As when applied as a consortium. Better phosphate nutrition, photosynthetic performance, and elevated glutathione levels were observed in consortium-treated plants particularly under As-stress. The consortium maintained heightened ROS levels in the plant without any deleterious effect and concomitantly boosted distinct antioxidant defense mechanisms in the shoot and root of As-treated plants. Increased consortium-mediated As(V) to As(III) conversion appeared to be a crucial step in As-detoxification/translocation. Four aquaporins were differentially regulated by the endophytes and/or As. The most interesting finding was the strong upregulation of an MRP transporter in the root by the As + endophytes, which suggested a major alteration of As-detoxification/accumulation pattern upon endophyte treatment that improved As-phytoremediation.