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The doping influenced carrier dynamics to maneuvering n-type to p-type semiconducting gold cluster assembly have been assessed. The resonance photoemission spectroscopic measurements corroborate an incremental rise in the density of states at the valence edge, the overlap of valence states due to doping, and the presence of distinct spin–orbit splitting and coupling in manganese-doping (Au7Mn) compared to gold clusters (Au8), originating from the relativistic effect resulted in a semiconducting property. The work function dependent current–voltage characteristics in metal–semiconductor configuration show Ohmic and Schottky behaviors assorting p-type carriers in Au7Mn in contrast to the n-type Au8 and are presenting an atomic cluster based fast electronic device. [ABSTRACT FROM AUTHOR]

The outstanding catalytic property of cerium oxide (CeO2) strongly depends on the polaron formation due to the oxygen vacancy ( V ̈ O ) defect and Ce4+ to Ce3+ transformation. Temperature plays an important role in the case of polaron generation in CeO2 and highly influences its electrical transport properties. Therefore, a much needed attention is required for detailed understanding of the effect of temperature on polaron formation and oxygen vacancy migration to get an idea about the improvement in the redox property of ceria. In this work, we have probed the generation of polarons in CeO2 thin-film deposited on a silicon (Si) substrate using the resonance photoemission spectroscopy (RPES) study. The RPES data show an increase in polaron density at the substrate–film interface of the thermally annealed film, indicating the formation of an interfacial Ce2O3 layer, which is, indeed, a phase change from the cubic to hexagonal structure. This leads to a modified electronic band structure, which has an impact on the capacitance–voltage (C–V) characteristics. This result nicely correlates the microscopic property of polarons and the macroscopic transport property of ceria. [ABSTRACT FROM AUTHOR]

Highly pathogenic Burkholderia pseudomallei is the causative agent of melioidosis, a neglected tropical disease endemic in Southeast Asian tropical region. This bacterium encompasses diverse virulence factors which further undergo dynamic gene-expression flux as it transits through distinct environmental niches within the host which may lead to manifestation of differential clinical symptoms. B. pseudomallei, is classified as a Tier 1 select agent in the United States and regarded as a risk group 3 organism in India with the potential to be used as bioweapon. Considering these facts, it is vital to uncover both physiological and genetic heterogeneity of B. pseudomallei, particularly to identify any novel virulence factors that may contribute to pathogenicity. B. pseudomallei strain CM000113 was isolated from a clinical case in India, characterized it for its physiological, biochemical, and prominently genetic traits through WGS. It has a type 2 morphotype with faster doubling time and high biofilm producing capacity as compared to Pseudomonas aeruginosa. The genome size is 7.3 Mbp and it is phylogenetically close to B. pseudomallei strain Mahidol 1106a and Burkholderia mallei Turkey 2. We observed genetic heterogeneity, as key virulence factors that were identified shows sequence dissimilarity with reference strains. Additionally, presence of genomic islands, harbouring two virulence factors, GmhA and GmhB2, associated with pathogenesis indicates possibility of horizontal gene transfer. These results emphasize the need for an extensive study focusing the genome of B. pseudomallei and its associated heterogeneity, to identify molecular biomarkers aiding to develop point-of-care diagnostic kits for early diagnosis of melioidosis. [ABSTRACT FROM AUTHOR]

The leachability of low-level radioactive waste was meticulously evaluated to determine the efficacy of a cement–vermiculite matrix for immobilisation. Laboratory-scale blocks, with a cement-to-vermiculite ratio of 1:0.1, were subjected to the IAEA-recommended semi-dynamic leaching test using rainwater (RW) from the disposal site and demineralised water (DW) for comparative analysis. The experimental data elucidated the transport phenomena governing Cs-137 release from the matrix. A strong positive correlation was observed between pH, conductivity, and Cs-137 activity release, indicating their interdependent dynamics. This research derived mathematical equations for both single-source term models describing the entire leaching process and the most fitting combination models, based on statistical parameters. Key leaching parameters, including a diffusion coefficient of 5.83E-07 cm2/d, a dissolution velocity of 4.93E-05 cm/d, and a first-order kinetic rate constant of 8.00E-05 d−1, were established and used to identify the optimal leaching model. These parameters are crucial for future radiological impact assessments of the area. Various physico-chemical observations during the leaching period were documented, with efforts to elucidate their underlying causes. The cumulative Cs-137 release of less than 1% over the study period and a leachability index of 7.2 confirmed the matrices' suitability for immobilising the studied waste. Research highlights: Cs-137 is the major long-lived radionuclide present in low-level radioactive waste. Waste is immobilized in cement–vermiculite matrix and disposed in reinforced concrete trenches at disposal site, Tarapur. Cs-137 leaching from cement-waste products using rainwater and demineralised water is studied using IAEA standard leaching test. Integrity of block is studied and Leaching parameters are evaluated from observed cumulative leach fraction. Using statistical parameter, Index of agreement, best-fit leaching mechanism for Cs-137 was established. The efficiency of the matrix in immobilising low-level waste is found suitable with Leachability Index > 6. Diffusion is the underlying controlling leaching mechanism. [ABSTRACT FROM AUTHOR]

The effects of Co doping on the structural and magnetic properties of a frustrated layered rare earth based synthetic analog of mineral francisite [Cu3La(SeO3)2O2Cl;(LaCufr)] have been investigated experimentally with a prior theoretical input. We have estimated intra-layer and inter-layer exchange interactions from density functional theory, which reveals the strong antiferromagnetic (AFM) nature of the studied compounds. 10 at. % Co-doped CuLafr confirms incorporation of Co2+ at the Cu2+ site with the local environment around dopant Co nearly similar around that of host Cu. An observed field-induced meta-magnetic transition and a spin reorientation transition have been interpreted considering magnetic exchange interactions. Co-doped LaCufr exhibits a decrease in the AFM ordering temperature and the critical field corresponding to a meta-magnetic spin-flip type transition. The competition and modulation among different intra-layer exchange interactions upon incorporation of Co into the Cu site may lead to such situations. The evidence of spin–phonon coupling from Raman analysis in both compounds is noteworthy and enriches their magnetic properties. [ABSTRACT FROM AUTHOR]

Like any other facilities, nuclear facilities are likewise connected with risks to the personnel and environment. The impact assessment of any facility is one of the essential prerequisites for its smooth running. Uranium ore is processed through different stages, such as size reduction, leaching, filtration, product recovery and waste deposition. Different stages of the ore processing can redistribute the activity of radio-nuclides and their measurement is essential for the impact analysis of the facility. Variation in radon and gamma levels is internationally investigated as a marker for seasonality in the natural radiation environment of an area. Accordingly, investigation for both plant and solid waste disposal sites has been carried out for radon (222Rn) and gamma levels to examine the influence on the workers and environment. The radon concentration in the workplace is observed to vary between 20 and 150 Bq m−3, which is within the reference threshold of 300 Bq m−3 suggested in the ICRP recommendation (ICRP 2014). The impacts of the facility on the surrounding environment are indistinguishable from those of the background. Findings suggest that the seasonality of change in radon level is considerable at either site and the gamma level change in the mill is ascribed to the nature and quantity of the source rather than the seasonal influences. [ABSTRACT FROM AUTHOR]

This paper discusses the natural radioactivity levels in ilmenite ore and its final product. Two economically viable ores of titanium are ilmenite (FeO.TiO2) and rutile (TiO2). High-purity germanium (HPGe) detector was used to analyse samples of raw ore, its purified fraction and the final product (synthetic rutile). Radioactivity levels due to 238U and 232Th and its daughter products were estimated. The concentration of 238U and 232Th in raw ore, purified ore and synthetic rutile was found to be 204 ± 4 and 1208 ± 5, 89.0 ± 4 and 597.0 ± 4, 119 ± 2.5 and 398.0 ± 3 Bq/kg, respectively. The dose rates due to gamma photons estimated in raw ore and synthetic rutile were 572 nSv/h and 277 nSv/h, respectively. The activity index estimated was 5.3 for raw ore and 2.3 for final product (synthetic rutile). The final product contained only 25% of the radioactivity compared to the ore showing significant reduction in radioactivity due to the processing of the ore. [ABSTRACT FROM AUTHOR]

In view of the dispersible nature of the radiologically significant gaseous radon (222Rn) and its dependence on metrological variables, an investigation was carried out in the uranium mineralized region of Jaduguda. Two distinct locations, comprising of prototype dwellings and outdoor environment outside the dwellings were chosen for the comparative study. The investigation was carried out during monsoon, autumn and winter seasons so that a profile ranging from minima to maxima can be accounted. Along with the 222Rn concentration profile and gamma level, the metrological variables such as ambient temperature, pressure, relative humidity has also been investigated. Results of sixty six (66) outdoor and thirty nine (39) dwellings monitoring was found to have 222Rn concentration ranged from 9 to 68 Bq m−3 and 35 to 130 Bq m−3, respectively, in outdoor and indoor with corresponding average value of 222Rn concentration were found 34 ± 13 and 79 ± 24 Bq m−3, respectively. These values are well within the expected range of a uranium mineralized area. Also, the outdoor 222Rn activity concentration is about 43% of the indoor 222Rn activity concentration, which can be attributed to greater atmospheric dilution and related metrological variables like higher temperature. [ABSTRACT FROM AUTHOR]

The growing demand for prefabricated tailor-welded blanks in aircraft panel manufacturing stems from their ability to streamline assembly, reduce material usage, save time, and cut costs. Friction stir welding, known for overcoming common defects in conventional methods, is explored in this study. Similar materials with varying thicknesses are welded, evaluating performance with surface response methodology. Central composite design of experiments, with tool rotation speed and welding speed as factors, yields tensile strength, percentage elongation, and hardness as output responses. ANOVA confirms experimental design adequacy, and mathematical models reveal response surface trends. Microstructural analysis investigates material deposition in varying thickness workpieces. Tensile strength response surfaces show significant variations, with the peak of 149 MPa achieved at 900 rpm and 80 mm/min, approximately 80% of the base metal's strength. The highest and lowest tensile strength weld joints exhibit average grain sizes of 7.78 and 13.6 µm, respectively. [ABSTRACT FROM AUTHOR]

Research efforts are being devoted to realize colloidal, heavy metal ion free, and luminescent quantum dots. We address radiative recombination in Zn alloyed CuGaS2/ZnS core/shell chalcopyrite quantum dots (CQDs) emitting in the blue-green spectral region. QDs show a systematic increase in the optical band gap and emission energy with an increasing amount of Zn in their core. Intentionally making non-stoichiometric CQDs with core/shell geometry enables defect related emission with high intensity. The location of Cu related defect levels along with the valence band and conduction band edge was determined from electrochemical cyclic voltammetry (CV) measurements. The evolution of band gap energies with respect to Zn concentration examined using CV measurements matches well with the optical absorption data. The presence of Cu vacancies in off-stoichiometric samples introduces intra-gap levels, which serve as common acceptor levels for optical transitions. Luminescence transitions in these materials stem from the radiative recombination of electrons from conduction levels as well as donor levels, with holes localized at acceptor levels. Temperature dependent and excitation laser intensity dependent emission measurements confirm the role of the Cu vacancy related acceptor level in the emission. Local structure studies via extended X-ray absorption fine structure and X-ray absorption near edge structure analysis were carried out to understand how Zn is incorporated in CuGaS2 quantum dots and affects the luminescence. Electron spin resonance measurements confirm the presence of paramagnetic defect complexes. X-ray absorption near edge structure measurements indicate that Cu co-exists in +1 and +2 oxidation states in CuGaS2 quantum dots. [ABSTRACT FROM AUTHOR]

The feasibility study of the uranium mill tailings generated from the Turamdih process plant as a construction material was evaluated by making bricks using the tailings as one of the components of the bricks. Two major techniques, such as moulding and pressing, were used to produce bricks from the tailings. Mill tailings in the bricks varied from 15 to 62% with other materials such as sand, cement, gypsum, lime, bed materials, LD slag, fly ash, and aggregates. The major qualifying criteria, such as compressive strength, water absorption, leaching test, and 222Rn exhalation rate, were estimated using the standard methods to assess the suitability of the bricks for use as construction material. Three types of qualified bricks with different tailings compositions (30%, 40% and 50%), along with the other materials in bulk quantities, were produced and used in the model house to evaluate the associated in situ radiological hazards. The in situ mean 222Rn exhalation rates from walls were 0.0007 Bq/m2/s, 0.0012 Bq/m2/s, and 0.0021 Bq/m2/s made of tailings bricks with respective tailings compositions of 30, 40, and 50%. The maximum indoor radon concentration likely to be contributed by the 50% tailings bricks was estimated to be less than 20 Bq/m3 for minimum air changes of 0.5 per h. The estimated radium equivalent activity (Raeq) indicated that the bricks can be suitably used in industrial buildings, foundations of non-residential buildings, and the construction of roads and bridges without any significant radiological hazards to members of the public. [ABSTRACT FROM AUTHOR]

The eastern coast of India, particularly near the Rushikulya River Bay, has several industries, port and urban settlements, which makes it important to study the dissolved radon concentration in the groundwater as well as in the seawater of this area. In the present study, 20 samples (9 groundwater and 11 seawater samples) were analysed using the AlphaGUARD radon monitor for the naturally occurring 222Rn. The study reveals that radon concentration in the groundwater is higher, which varies between 631 and 3142 Bq m−3 in comparison with the radon concentration in coastal waters that have a range between 160 and 289 Bq m−3. The difference in the concentration of radon in the shallow groundwater and the seawater shows that proper accounting for radon in the system will lead to quantification of the submarine groundwater discharge in this coastal region. [ABSTRACT FROM AUTHOR]

Measurements of atmospheric release from underground uranium mine at Narwapahar in state of Jharkhand has been done to assess the discharged 222Rn at surface from ventilation shafts of mine. Annual volume of atmospheric discharge has been estimated around 6 × 109 m3 from ventilation shafts of mine with associated radon (222Rn) activity around 2.3 × 1013 Becquerel. Such a huge amount of radioactivity discharge in open atmosphere through underground uranium mine is always under consideration to assess the exposure of public residing in surrounding villages, if any. Realizing the non-negligible health hazards due to radon exposure, the present study has been carried out to measure the radon concentrations in surface discharged air. A portable radon-measuring device (Alpha-guard) is used to determine the radon levels. Alpha-guard is used in diffusion mode for the measurements of radon concentration in the vicinity of ventilation shafts of the U-mine. The study reveals that the discharge of radon from mine exhaust is confined within 100 m of the discharge point of the mine (in no man area within mine premises) and it does not affect the inhalation hazards to inhabitants residing in public domain in nearby villages. [ABSTRACT FROM AUTHOR]

A study on natural radioactivity in soil around Tummalapalle uranium mineralised region was carried out. The aim of this study was to find the activity of primordial radionuclides 226Ra, 232Th and 40 K over the span of 5 years from 2018 to 2022 to understand the trend of activity of radionuclides in soil and impact of mining activities on the surrounding soil. The overall average activity of 226Ra, 232Th and 40 K over the years has been found to be 25 Bq/kg, 40 Bq/kg and 478 Bq/kg, respectively. The 226Ra and 232Th activities have been found to be less, whereas 40 K activity has been found to be slightly higher than the worldwide average of 32, 45 and 412 Bq/kg. The activity of radionuclides over the years does not show any increasing trend, which indicates that there is no impact of mining activities in the region on the soil in surrounding environment. Radium equivalent for soils was found to be 117.10 Bqkg−1, which is lower than the recommended limit of 370 Bqkg−1, and the annual effective external dose was found to be 345.56 µSvy−1, which is less than the worldwide average of 460 µSvy−1. External hazard index was found to be 0.35 Bq kg−1, which indicates insignificant radiation hazard from natural radionuclides in soil. [ABSTRACT FROM AUTHOR]

Gamma spectrometry technique is regularly used for the quantification of different gamma-emitting radionuclides in environmental matrices and other synthetic samples. This is a non-destructive comparative technique which requires the usage of Certified Reference materials from International agencies like IAEA, NIST, etc. Limited availability and high cost of these Certified Reference materials pose a major hindrance in their acquisition by radiometric laboratories, motivating their indigenous preparation. A total of five sets of two types of filter papers and one blank were prepared by spiking with variable activity of 226Ra by gravimetric and volumetric measurements in a standard geometry. Efficiency of both filter paper standards together, varied from 19.7 to 20.3% in the selected geometry on HPGe-based high-resolution gamma spectrometry system. MDA values were also observed to be suitable for environmental air particulate measurements. The values of efficiencies and MDA obtained indicate that these air filter standards can qualify as candidate reference standards for regular gamma spectrometric counting of air particulates on filter paper media. [ABSTRACT FROM AUTHOR]

An inter-comparison exercise is a quality control tool to standardize a laboratory and was performed between HPU lab at Nuclear Fuel Complex and RPS (NF) lab at Bhabha Atomic Research Centre to determine and compare the concentration of primordial radionuclides in a zircon sample received from Health Physics Unit (HPU), Indian Rare Earth Limited Manavalakurichi weighing 470 g. RPS (NF) lab is annually participating in international inter-comparison exercise conducted by IAEA and is a nodal laboratory for the in-house inter-laboratory comparison exercise. Thus, its values are considered true values. The measured concentrations for 238U and 232Th in zircon sample do not vary considerably as 0.37% variation is observed in true value and measured value of 238U and 0.32% variation is observed in true value and measured value of 232Th. U score is also calculated from the results obtained where it is found to be 0.124 for 238U and 0.195 for 232Th. Trueness and precision tests are also performed, and the laboratory results are found to be "acceptable". It represents that the laboratory performance is evaluated as satisfactory and does not significantly differ from the expected values as per the statistical tools. This ensures that the analytical measurement results of the laboratory are reliable and traceable to reference standard laboratory. [ABSTRACT FROM AUTHOR]

A closed container having a specified quantity of 226Ra was constructed as encapsulated 226Ra–222Rn source. The source in the form of a modified Lucas cell (LC) was used for standardization of Lucas cell alpha counting system. The performance of the prepared source was evaluated by simultaneous measurement of dissolved radon in water by Lucas cell method using alpha counting system and Alpha guard. Radon alpha counting system measures dissolved radon in water sample by gross alpha counting of aerated dissolved transferred to LC. The same samples were also measured simultaneously by Alpha guard using instant measurement of emanated radon in a closed circuit. The gross alpha counting method using the radon counting system produced result that is closely matching with the Alpha guard measurement. This validates the calibration of radon counting system by designed encapsulated source. The study provides an alternative for calibration in the absence of expensive radon source available in the market. [ABSTRACT FROM AUTHOR]

Underground uranium mines, in particular, is associated with radiological conditions normally not anticipated in other mining industries. Depending on the grade and characteristics of the uranium deposit, the radiological hazard considerations may widely vary. Although short lived radon progeny are the major contributor of individual dose to the miners, dose assessment using their activity concentration data is normally avoided. Mine dust, diesel fumes, high humidity and seepage from the surrounding surface poses additional difficulty in direct estimation of radon progeny activity concentration. Individual doses are computed through radon (222Rn) monitoring data and equilibrium ratio (F) between radon and its short lived progeny. Both ambient and passive techniques are used in Indian uranium mines for the dose assessment but the passive technique is preferred over the ambient as the later can explicitly account the individual worker during its uses. The device, Personal Radon Dosimeter (PRD), based on nuclear track registry on a LR-115 Kotak film has indigenously been designed after detailed scientific studies. Basic features of this device, their uses, track registry and calibration aspects along with dose assessment methodology of uranium miners are provided in the paper. [ABSTRACT FROM AUTHOR]

Gases from the breath exhalation can be used for the detection and estimation of associated contaminant in the human body. For the estimation of 226Ra body burden through the analyses of radon (222Rn) in the exhaled breath, similar technique has been considered for uranium miners in India. Initial experiments for Jaduguda underground uranium mine workers were based on qualitative approach due to the limitations of the sensitivity of the then available techniques. The inert gas 222Rn after its formation is soluble in the blood, may escape from the human body like other dissolved gases at lung/blood interface which can be removed through exhalation. Using a sensitive device that can effectively analyze the low activity concentration of radon, 226Ra body burden of the uranium miner can be estimated. The working principle, description and utility of the device as well as estimated 226Ra body burden are provided in the paper. Examination results of 244 subjects of uranium mines have shown a variation in the radium (226Ra) body burden from 0.54 to 3.75 kBq. The inexpensive technique can effectively be used in the field conditions due to high sensitivity, portability, low sampling time and minimal instrumentation requirements. [ABSTRACT FROM AUTHOR]

Participation in proficiency tests is an essential part of quality assurance activities for any laboratory involved in radiation metrology. Radioanalytical laboratory, Health Physics Division, BARC, regularly participates in national and international proficiency tests to demonstrate its radiometric capabilities for estimation of low-level natural and anthropogenic radionuclides in environmental matrices. The laboratory has been participating in annual IAEA Proficiency Tests conducted by Terrestrial Environmental Laboratory (TEL), IAEA, for estimation of natural radionuclides as well as fission and activation products in natural and spiked samples. This paper presents the results of estimation of 134Cs and 137Cs (two most important anthropogenic radionuclides that may be released from nuclear reactors during accident conditions) in spiked water samples in last five years of IAEA Proficiency Tests during 2018–2022. All results were lying well within 1σ level of the target values indicating the excellent analytical capability of this laboratory for analysis of 134Cs and 137Cs in aquatic environment. [ABSTRACT FROM AUTHOR]

The detection and measurement of radionuclides are indispensable processes, crucially guided by particle and photon emission mechanisms. Regulatory agencies and policymakers demand precise measurements to ensure compliance with safety standards and environmental protection mandates. To convert detection rates into meaningful activity values, certain vital parameters must be derived, necessitating validation through reference measurements, technical innovations, and proficiency testing. Gross alpha activity assessment holds particular significance in both finished products and the waste generated within naturally occurring radioactive materials (NORM) industries. The thickness of the radiation source emerges as a pivotal factor influencing gross alpha activity determination, owing to the energy losses incurred through self-absorption processes. This study endeavors to comprehensively investigate the impact of self-absorption in relation to source thickness, alongside an exploration of the associated procedural considerations. The research encompasses theoretical examinations of the range and stopping power of alpha particles as they interact with the source material itself, complemented by empirical measurements involving sources of varying thicknesses. Specifically, this study examines the influence of source thickness on the measurement of alpha activity within radioactive waste materials, originating from front-end nuclear facilities. In the context of this study, liquid wastes arise during the ore processing into uranium concentrate (sodium diuranate), subsequently conveyed to tailing ponds in slurry form. Solid wastes, on the other hand, predominantly consist of waste rock fragments produced during mining operations. A notable observation underscores the significance of self-absorption correction factors: In their absence, the measured values of alpha-specific activity experience substantial underestimation. This investigation yields self-absorption correction factors that have been quantified for varying source thicknesses. For liquid wastes, a second-degree polynomial fit, and for solid waste, a linear fit have been applied to these correction factors, facilitating improved accuracy in alpha activity measurements within radioactive samples. This research not only enhances our understanding of the intricate interplay between source thickness and self-absorption but also provides valuable insights for refining measurement methodologies in radiological assessments, especially concerning gross alpha activities in radioactive waste materials. [ABSTRACT FROM AUTHOR]

Ambient gamma radiation levels due to natural and anthropogenic sources play an important role in low level gamma spectrometric measurements of different sample matrices. Minimum detection level (MDL) of a high-resolution gamma spectrometry system directly depends on the background radiation levels. The variation of background radiation level due to the location (surface level or below ground level) of the laboratory housing the gamma spectrometric system and the impact of different shielding types is discussed in this study. Relocation of the system to a below ground level laboratory significantly brought down the background induced due to cosmic components. Corresponding reduction in count rates for major gamma emitters ranged from 36 to 59%. Consequently, the MDLs for corresponding peaks improved by 20 to 36%. Improvising the lead bricks-based passive shielding for the gamma spectrometry system to circular lead ring with graded Cu+Sn lining minimised the gamma background due to streaming of gamma rays through lead bricks and reduced the overall background. The combined effect of the location of laboratory below ground level and graded lead shielding resulted in reduction of MDL of the gamma spectrometry system for major gamma peaks by 54 to 80%. [ABSTRACT FROM AUTHOR]

The inter-comparison exercise results carried as a part of external quality control helps in establishing the accuracy and uncertainty of the method and the measurement system. The performance evaluation is based on the statistical performance indicators such as precision, trueness, relative bias and z-score. Z-score is used for scaling the difference between a participant's result and the assigned value for the concentration of the radio-analyte. It allows interpreting the data with different means and standard deviations and placing them on a common scale. This standard scale was used to compare result of the proficiency test made over the years for different radionuclides in matrices such as water, soil, sediment, seaweed, rice grain, having variable mean and standard deviation. [ABSTRACT FROM AUTHOR]

This paper discusses the different methods and instruments followed in India for the estimation of 222Rn, 220Rn, and their progeny. Radon concentration is either directly measured from radon alpha or its progeny alpha emissions. The duration of sampling, necessary information and specific application influence the selection of a particular monitor. In India, we use indigenously developed instruments like scintillation cells, LLRDs, electrostatic collection instruments, electret ion chamber, pulse ionization chamber-based Alpha Guard, electrostatic collection of Radon progeny atoms by RAD7 and Radon Scout Plus for the measurement of these carcinogenic gases. Scintillation cell-based measurement is found to be most reliable for the mine environment whereas highly sensitive instruments like ionization chamber and silicon detector are preferred for continuous radon tracking. Solid-state nuclear track detectors have also been used for long-term radon estimation covering the diurnal and seasonal variations. [ABSTRACT FROM AUTHOR]

The cornerstone of the study is to quantify the 222Rn/220Rn levels and the associated health risk in the environment of a heavy mineral-rich area in India. 222Rn and 220Rn activity was measured in environmental resources like soil, water, and indoor air. The analysis was performed using a well-calibrated online 222Rn/220Rn monitor (RAD 7) which is having a solid-state semiconductor detector system. The 222Rn depth profile in soil gas and exhalation rates of 222Rn and 220Rn from soil were monitored. The measured 222Rn activity in the indoor air of the study area concluded an effective radiation dose of 0.44–1.81 mSv.y−1 and an ELCR of 0.17–0.7%. Groundwater and surface waters from the high-background-radiation area were also analysed for dissolved 222Rn activity which contributes to a total radiation dose from 2.7 to 21.4 µSv.y−1. [ABSTRACT FROM AUTHOR]

Ba (Fe 1 / 2 Nb 1 / 2) O 3 ceramics are considered to be promising for technological applications owing to their high dielectric constant over a wide range of temperatures. However, there exists considerable discrepancy over the structural details. We address this discrepancy through a combined x-ray diffraction at room temperature and neutron powder diffraction measurements in the range from 5 K up to room temperature, supplemented by a comparative analysis of the earlier reported structures. Our study reveals a cubic structure with space group P m 3 ¯ m at all measured temperatures. Further, the x-ray near edge structure and extended x-ray absorption fine structure studies on the local environment of the Fe ions is consistent with the cubic symmetry. An appropriate value of U for DFT+ U calculations is obtained by comparison with x-ray absorption spectroscopy, which agrees well with the earlier reported electronic properties. [ABSTRACT FROM AUTHOR]

Reformist approaches to multiple sequence alignment (MSA) needed dropping an MSA at each alignment phase. But it illustrates the evidence of gap scoring rates for exact alignment. In the literature it has three types of sequences; Ribonucleic Acid, Deoxyribonucleic Acid, and Proteins. The MSA has been represented as a sequence alignment problem and solved using dynamic programming techniques. Due to the presence of a huge length of sequences in the MSA, the alignment of these sequences is complicated and time taking, even though sometimes optimal solution is not obtained. Therefore, MSA in the literature is categorized into the NP-complete. The genetic algorithm (GA) and its variations have been successfully used for solving NP-complete and thus prominently may be used for MSA problem that maximizes the sequence similarity. To address an MSA problem, an effective GA-based algorithm is explored. The "Non-dominated Sorting Genetic Algorithm (GA)-II" (NSGA-II) is extensively used model to explore this problem. To solve the MSA optimization problems, an adapted NSGA-II has been proposed and compressive analysis has been performed to verify the potency of the work deliberated here. [ABSTRACT FROM AUTHOR]

X‐ray absorption fine structure (XAFS) at the Cu K‐edge in copper complexes of L‐aspartic acid (asp) and L‐glutamic acid (glu), namely, [Cu(L‐asp)(H2O)].H2O (1) and [Cu(L‐glu)(H2O)].H2O (2) have been investigated using synchrotron radiation. Though, the crystal structure of both of the complexes 1 and 2 have been studied earlier using x‐ray crystallography, it was considered worthwhile to study the coordination geometry and electronic nature of Cu metal center using XAFS. EXAFS analysis indicated that Cu has distorted tetragonal pyramidal and distorted octahedral coordination in complexes, respectively. The XANES spectra have been simulated for the Cu center in the complexes and compared with the experimental XANES spectra. Further, p‐DOS and d‐DOS calculated simultaneously for absorbing Cu metal center have been correlated with the features and shape of the simulated XANES spectra as well as the experimental spectra. [ABSTRACT FROM AUTHOR]

Asthma and Chronic Obstructive Pulmonary Disease (COPD) are principally lifestyle related chronic inflammatory airway disease. They are globally associated with various systemic comorbidities and mortality. Osteoporosis is the common associated metabolic bone disease with respiratory disturbances, which affect the prognosis and increase mortality and morbidity in the patients. Apart from OSTEOPOROSIS, exhaustive attention has been paid towards other associated systemic comorbidities like cardiovascular diseases, cerebrovascular diseases, metabolic syndrome, malnutrition, skeletal muscle dysfunction (sarcopenia), anxiety, depression and so on (Iheanacho et al. in Int J Chronic Obstr Pulm Dis 15:439–460, 2020; Singh et al. in Eur Respir J 53:1900164, 2019). Osteoporosis is a significant extrapulmonary manifestation in asthma and COPD, which are grossly neglected and inadequately treated. The comorbidities have significant impact in terms of morbidity, mortality and economic burden in asthma and COPD patients, hence management of asthma and COPD should comprise thorough management, as this will also have an impact on the outcome of these patients. Various risk factors such as smoking, systemic inflammation, vitamin deficiency, and the use of oral or inhaled corticosteroid are responsible for osteoporosis in patients with asthma and COPD. The presence of osteoporosis in patients with asthma and COPD is invariably asymptomatic unless complicated by fragility fractures, therefore, it is necessary to explore the pathogenesis of osteoporosis in asthma and COPD and special attention is to be paid for early recognition of patients at high risk for osteoporosis in these patients. This chapter is focussed on osteoporosis as an extrapulmonary manifestation of asthma and COPD with an emphasis on the pathogenesis, risk factor, potential mechanism of osteoporosis, diagnosis, and prevention with passing reference to treatment as well in asthma and COPD patients. [ABSTRACT FROM AUTHOR]

The most prevalent metabolic bone disease, osteoporosis, is characterized by a decrease in bone mineral density and alterations to the bone's microstructure, both of which can result in fragility fractures. It affects a significant section of the population. Acute or chronic pain from these fractures is typical in elderly adults with other coexisting conditions. Since the antiresorptive medication only partially reduces pain, other analgesics are required for effective pain management. NSAIDs or selective COX-2 inhibitors can reduce acute pain, but persistent neuropathic pain is difficult to manage with these drugs. Opioids have their adverse effects and safety concerns, although they can be used to address acute or chronic pain. Hence, a multifaceted approach is to be implemented, including pharmacological and nonpharmacological therapy and surgical treatment in a selected number of cases. This chapter briefly describes the etiology of pain, its mechanism, and pain management in osteoporotic patients. [ABSTRACT FROM AUTHOR]

Use of glucocorticoid in various diseases including rheumatology and respiratory diseases is on the rise because of its prompt beneficial effects. This culminates in osteoporosis and fragility fractures. Judicious use of glucocorticoid hence calls for attention with regard to the dose schedule, route of administration and accompanying enhancing factors. Institution of proper therapeutic management as per WHO risk stratification with anabolic and/or resorptive drugs like bisphosphonates, teriparatide or denosumab is necessary to prevent the eventuality of fragility fractures. Even otherwise, knowledge of glucocorticoid, its metabolism, various dose schedules, adverse effects are areas worth discussing. [ABSTRACT FROM AUTHOR]

Near-infrared (NIR) observations of normal Type Ia supernovae (SNe Ia) obtained between 150 and 500 d past maximum light reveal the existence of an extended plateau. Here, we present observations of the underluminous, 1991bg-like SN 2021qvv. Early, ground-based optical and NIR observations show that SN 2021qvv is similar to SN 2006mr, making it one of the dimmest, fastest evolving 1991bg-like SNe to date. Late-time (170–250 d) Hubble Space Telescope observations of SN 2021qvv reveal no sign of a plateau. An extrapolation of these observations backwards to earlier-phase NIR observations of SN 2006mr suggests the complete absence of an NIR plateau, at least out to 250 d. This absence may be due to a higher ionization state of the ejecta, as predicted by certain sub-Chandrasekhar-mass detonation models, or to the lower temperatures of the ejecta of 1991bg-like SNe, relative to normal SNe Ia, which might preclude their becoming fluorescent and shifting ultraviolet light into the NIR. This suggestion can be tested by acquiring NIR imaging of a sample of 1991bg-like SNe that covers the entire range from slowly evolving to fast-evolving events (0.2 ≲ s BV ≲ 0.6). A detection of the NIR plateau in slower evolving, hotter 1991bg-like SNe would provide further evidence that these SNe exist along a continuum with normal SNe Ia. Theoretical progenitor and explosion scenarios would then have to match the observed properties of both SN Ia subtypes. [ABSTRACT FROM AUTHOR]

Here, we report the synthesis of a novel quaternary Heusler alloy CoMnCrGa and its structural, magnetic, transport and electronic properties using both experimental and theoretical methods. DFT calculations on an ordered crystal structure with specific atomic positions (Ga at 4a, Mn at 4b, Cr at 4c and Co at 4d) reveal a half-metallic ferromagnetic (HMF) ground state having a very high spin polarization of 96.1%. In this work we show that despite having a mix of Mn (4b) and Cr (4c) atoms, CoMnCrGa exhibits all the signatures of the HMF characteristic, viz., adherence to the Slater–Pauling (S–P) rule to isothermal saturation magnetization and the absence of magnon scattering in temperature dependent resistivity data. Given its high TC (∼807 K), low magnetic moment and very high spin-polarization, the compound is a promising candidate for room temperature spintronics applications. [ABSTRACT FROM AUTHOR]

Single parent adoption (SPA) is a relatively new construct worldwide and in India. The Ministry of Women and Child Development, Government of India, has laid down criteria for adoption in general and SPA in particular, in conjunction with the Juvenile Justice Act (Care and Protection of Children), 2015. There is scant literature on this topic of SPA, more so in India, that looks into the various psychological nuances of SPA from a mental health professional's (MHP) perspective. This review paper aims to assess SPA from the perspective of a MHP that will focus on its various legal nuances as well as the psychological connotations attached to it. For this, a search strategy was employed that included a thorough literature search from two databases (PubMed and Google Scholar) with relevant keywords related to the topic. The various legal issues pertaining to SPA in the current scenario, the psychological issues and challenges faced by single parents, the behavioral outcomes of adoptees who are adopted by single parents, and ways to deal with the various obstacles of SPA are discussed. [ABSTRACT FROM AUTHOR]

We report on the large-area and high-quality growth of single- to few-monolayer thick MoS2 thin films on oxidized Si (100) substrates via the pulsed laser deposition method. Our Raman, x-ray photoelectron spectroscopic, and FE-SEM measurements confirmed that atomically thin MoS2 layers are highly uniform and are stoichiometric. We found a type-I band alignment at the MoS2/SiO2 heterointerfaces through photoemission spectroscopic valence-band measurements. The valence- and conduction band offset (VBO and CBO) at the 1L MoS2/SiO2 interface was observed to be 3.91 and 2.96 ± 0.05 eV, respectively. The values of VBO and CBO increase up to 4.15 and 3.56 ± 0.05 eV, respectively, with an increase in the MoS2 layer number. This observation can be attributed to the shift of the Mo-4dz2 orbitals due to interlayer coupling for thicker MoS2 films, reducing its bandgap, resulting in an increment in VBO and CBO values. [ABSTRACT FROM AUTHOR]

Detailed structural and optical properties of α-(AlxCr1−x)2O3 (0 ≤ x ≤ 1) synthesized by the solid state reaction method have been investigated. Single phase α-(AlxCr1−x)2O3 with space group R 3 ¯ c is obtained for the full composition range of 0 ≤ x ≤ 1. Variations in the lattice parameters a and c have been determined. Lattice parameter c follows Vegard's law, while the lattice parameter a shows a clear deviation with a bowing parameter of −0.035 Å. This behavior of the lattice parameters of α-(AlxCr1−x)2O3 with x is explained in detail by studying the local structure. Extended x-ray absorption fine structure spectroscopy shows a reduction in the values of Cr–O bond lengths with composition x. Optical absorption measurements of α-(Al1−xCrx)2O3 for 0 ≤ x ≤ 1 show a large bandgap tunability of 1.9 eV (from 3.4 eV to 5.3 eV). The photoemission spectroscopy data and the analysis of partial density of states obtained from first principles electronic structure calculations suggest that the valence band maxima is mainly composed of Cr 3d levels, which hybridize with the O 2p levels. Increased contribution of O 2p partial density of states is observed with Al substitution, which is expected to enhance p-type carrier conduction in the α-(AlxCr1−x)2O3 system as compared to the parent α-Cr2O3 system. Thus, the large bandgap, its tunability in the UV region, and the predicted enhancement of p-type conductivity in the α-(AlxCr1−x)2O3 system make it a potential candidate for application in UV based photo-detectors and transparent electronics. [ABSTRACT FROM AUTHOR]

We present the results of resonant photoemission spectroscopy experiments on Mo 1 − x Re x alloy compositions spanning over two electronic topological transitions (ETTs) at critical concentrations x C 1 = 0.05 and x C 2 = 0.11. Photoelectrons show an additional resonance (R 3) in constant initial state spectra of alloys along with two resonances (R 1 and R 2), which are similar to those observed in molybdenum. All the resonances show Fano-like line shapes. Asymmetry parameter q of resonances R 1 and R 3 of alloys is observed to be large and negative. Our analysis suggests that the origin of large negative q is associated with phonon assisted interband scattering between Mo-like states and the narrow band that appeared due to ETT. [ABSTRACT FROM AUTHOR]

In recent times, ultra-thin films of hafnium oxide (HfO2) have shown ferroelectricity (FE) attributed to the orthorhombic (o) phase of HfO2 with space group Pca21. This polar o-phase could be stabilized in the doped thin film of the oxide. In the present work, both polar and non-polar o-phases of HfO2 could be stabilized in Gd-doped bulk polycrystalline HfO2. Rietveld analysis of XRD data shows that the relative population of o-phases in the presence of the monoclinic (m) phase of HfO2 increases with increasing Gd-content. The local environment around the host atom has been investigated by time differential perturbed angular correlation (TDPAC) spectroscopy, synchrotron based X-ray near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) measurements. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) measurements showed a reduction in grain size with increasing Gd-dopant indicating a solute drag effect. It could be established that the segregation of the Gd-dopant in the grain boundary is a thermodynamically favorable process and the solute drag effect plays an important role in nucleation of the o-phase in bulk HfO2. Stabilization of Gd in both Pbca and Pca21 phases of HfO2 was supported by defect formation energy calculations using density functional theory (DFT). The present study has important implications in future applications of HfO2 in ferroelectric devices and in understanding the role of dopants in stabilizing the o-phase of HfO2 in the bulk. [ABSTRACT FROM AUTHOR]

Even though the use of uranium mill tailings as a construction material is prohibitive such prototype dwellings can be constructed for developing models for the human exposure assessment. Among the potential challenges of uranium mill tailings build-up of radon (222Rn) from the tailings pile and subsequent migration following dispersion is assumed significance due to the associated inhalation hazard of its progeny. Sources of such exposure are predominantly considered as the 226Ra (parent of 222Rn) present in the construction material and underlying geophysical characteristics. In the present investigation, a model is developed presuming the use of mill tailings as the construction material of a dwelling (prototype). The numerical model prediction for 1.14 Air Changes per Hour (ACH) reflects that the level can be approximated at 300 Bq m−3, a reference level proposed in ICRP recommendation (ICRP 2014). [ABSTRACT FROM AUTHOR]

Background: The present study was conducted to study the resilience capacity towards changing climate of a farming community who reared specifically Murrah buffaloes in their livestock production system for their livelihood. As the study area was breeding tract of Murrah buffalo, hence in-depth study of resilience was performed in frequent changing climate. Methods: In order to assess the resilience capacity and their relation with socioeconomic characteristic, total 320 Murrah buffalo farmers across four districts in India's Trans-Gangetic Plain, data were gathered using focused group discussions, PRA tools and in person interviews. Statistical tools such as principal component analysis for index development, cumulative square root methods for categorization of respondents and regression analysis were performed for exploring relationship. Result: Result depicted that majority of the farmers has medium level of climate resilience index score i.e. 0.456. Further, it was found that farmer's involvement in social institute such as, gram panchayat, agriculture and dairy co-operative society, self-help group, farmers' association and others affected their resilience capacity in changing climatic scenario. The need for better technology inclusion and access to more formal systems of finance is necessary to increase the overall resilience capacity of households. [ABSTRACT FROM AUTHOR]

Background: Infertility is a disease of the male or female reproductive system defined by the failure to achieve a pregnancy after 12 months or more of regular unprotected sexual intercourse. Aims: The aim of this study was to estimate the prevalence of infertility and its association with reproductive risk factors amongst women of reproductive age group (18-49 years) in district Sonepat, Haryana. Settings and Design: This observational community-based cross-sectional study was conducted amongst 444 reproductive age group (18-49 years) women residing in district Sonepat, from August 2021 to May 2022. Materials and Methods: A simple random sampling technique was used to select the study subjects. After taking written informed consent, all the participants were interviewed using a pre-designed, pre-tested semi-structured questionnaire for desired information. Statistical Analysis Used: Mean and standard deviation (SD) were calculated for quantitative data. Percentages and proportions were calculated for qualitative data. Results: Out of 444 study population, majority of women were fertile (88.7%), while 6.3% of women were secondary infertile and 5% of women were primary infertile. Most women were aged between 30 and 39 years. The difference of occurrence of infertility in relation to genital discharge (P = 0.049), genital ulcer/sores (P ≤ 0.001), groin swelling (P ≤ 0.001), warts (P = 0.015), menstrual cycle duration (P ≤ 0.001) and menstrual flow amount (P = 0.048) was statistically significant. The mean age of menarche for the female with infertility was 14.34 years (standard deviation = 1.40). Conclusion: Almost all of the symptoms of sexually transmitted infection/reproductive tract infection were high amongst infertile females. Awareness generation about the preventable risk factors and provision of infertility care services at primary healthcare facilities will be of use in addressing infertility in Sonepat. [ABSTRACT FROM AUTHOR]

The study's aim is to assess drinking water quality in the springs of the state of Sikkim. Physico-chemical properties and pathogenic bacterial presence (including their drug resistance profile) have been studied across seasons. Important findings are (a) the concentration of iron and manganese is above the permissible limit; (b) high contamination with pathogenic bacteria exists. These are Escherichia coli (22.4%) followed by Klebsiella spp. (20.6%), Citrobacter spp. (7.5%) and Shigella spp. (7.1%). Isolated samples show that these bacteria have high resistance to common antibiotics. [ABSTRACT FROM AUTHOR]

The feasibility of X-ray absorption fine-structure (XAFS) experiments of ultradilute metalloproteins under in vivo conditions (T = 300 K, pH = 7) at the BL-9 bending-magnet beamline (Indus-2) is reported, using as an example analogous synthetic Zn (0.1 mM) M1dr solution. The (Zn K-edge) XAFS of M1dr solution was measured with a four-element silicon drift detector. The first-shell fit was tested and found to be robust against statistical noise, generating reliable nearest-neighbor bond results. The results are found to be invariant between physiological and non-physiological conditions, which confirms the robust coordination chemistry of Zn with important biological implications. The scope of improving spectral quality for accommodation of higher-shell analysis is addressed. [ABSTRACT FROM AUTHOR]

Background: Hospital Waste collection and proper disposal has become a significant concern for both the medical and general community. It is estimated that 10-25% of healthcare waste is hazardous, with the potential to create a variety of health problems. Handling, segregation, mutilation, disinfection, storage, transportation and final disposal are vital steps for safe and scientific management of Hospital waste in any establishment. Objectives: To assess the knowledge of hospital Waste management among healthcare personnel working in a tertiary care centre. Methods: To assess the knowledge of hospital Waste management among healthcare personnel working in a tertiary care hospital. A hospital based cross sectional study was conducted. The Study participants included nursing staff, ward boys and cleaning staff working in the institute who deal with Medical waste and were selected randomly to make the sample size of 250 with equal representation in both categories. A pretested semi-structured questionnaire was used. Results: The study showed gaps in the knowledge of categories of respondents. The knowledge of the existence of Medical waste management in nurses was (79%), as well as in cleaning staff was (37%). The knowledge in practical aspects of Medical waste management was better in nurses, as compare to cleaning staff. [ABSTRACT FROM AUTHOR]

The optical performance of low-bilayer-thickness metallic multilayers (ML) can be improved significantly by limiting the intermixing of consecutive layers at the interfaces. Barrier layers are supposed to exhibit a decisive role in controlling diffusion across the interfaces. The element-specific grazing incidence extended X-ray absorption fine structure technique using synchrotron radiation has been used in conjunction with grazing incidence X-ray reflectivity and diffuse X-ray scattering measurements to study the impact of the two most common barrier layers, viz., C and B4C, at the interfaces of Cr/Sc MLs. The diffusion propagation is reduced by both the barrier layers; however, it is found that the improvement is more significant with the B4C barrier layer. It is seen that C forms an intermixed layer with Sc and leads to carbide formation at the interface, which then acts as shielding and prevents further interdiffusion, while B4C hardly penetrates into Sc and stops the overlap between Sc and Cr directly by wetting the corresponding interface. Thus, the above measurements reveal crucial and precise information regarding the elemental diffusion kinetics at the interfaces of Cr/Sc MLs in a non-destructive way, which is very important for technological applications of these MLs as X-ray optical devices. [ABSTRACT FROM AUTHOR]