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Natural polymer-based hydrogels as prospective tissue equivalent materials for radiation therapy and dosimetry
Natural polymer-based hydrogels have been extensively employed in tissue engineering and biomedical applications, owing to their biodegradability and biocompatibility. In the present work, we have investigated the efficacy of hydrogels such as agarose, hyaluronan, gelatin, carrageenan, chitosan, sodium alginate and collagen as tissue equivalent materials with respect to photon and charged particle (electron, proton and alpha particle) interactions, for use in radiation therapy and dosimetry. Tissue equivalence has been investigated by computing photon mass energy absorption coefficient (?en/?), kinetic energy released per unit mass (KERMA), equivalent atomic number (Zeq) and energy absorption build-up factors (EABF) relative to human tissues (soft tissue, cortical bone, skeletal muscle, breast tissue, lung tissue, adipose tissue, skin tissue, brain) in the energy range of 0.01515MeV. Ratio of effective atomic numbers (Zeff) have been examined for tissue-equivalence in the energy range of 10keV1GeV for charged particle interactions. Analysis using standard theoretical formulations revealed that all the selected natural polymers can serve as good tissue equivalent materials with respect to all human tissues except cortical bone. Notably, sodium alginate, collagen and hyaluronan are found to have radiation interaction characteristics close to that of human tissues. These results would be useful in deciding on the suitability of a natural polymer hydrogel as tissue substitute in the desired energy range. 2021, Australasian College of Physical Scientists and Engineers in Medicine. -
Transparent and lead-free Dy3+ doped lithium borate glasses for photon and neutron shielding applications
The exploration of trivalent rare-earth ion-doped lithium calcium borate glasses has surged recently due to their potential applications in solid-state lasers, medical imaging, and radiation shielding. This study focuses on transparent and lead-free Dy3+ doped lithium borate glasses for their efficacy as versatile radiation shields. Glasses with the chemical composition 50(Li2O): 20(CaO): 30?x(B2O3): x(Dy2O3) (x = 0.0, 0.1, 0.3, 0.5 and 1.0 mol% Dy2O3) were investigated. The structural changes in the lithium calcium borate glasses with Dy2O3 were investigated using Fourier transform infrared spectra of the synthesized glass samples. Experimental mass attenuation coefficients (?/?) of the glasses have been determined using NaI(Tl) detector spectrometer in the energy range of 0.356-1.332 MeV. Photon interaction parameters were computed using PAGEX software in the energy range of 0.015-15 MeV. Relative dose distribution (RDD) and specific absorbed fraction of energy (SAFE) were also investigated. Additionally, macroscopic fast neutron removal cross-sections ( ? R ) were computed to estimate neutron shielding efficiencies. The sample with 1 mol% Dy2O3(LBD1), displayed superior photon and neutron attenuation properties. Glasses with lower Dy2O3 doping concentrations (?1 mol%) showed comparable half-value layer and effective atomic number to reference materials with higher doping concentrations. Increasing Dy2O3 doping concentration improved photon shielding parameters, with ? R values ranging from 0.1460 to 0.1475 cm?1, higher than those of ordinary concrete, RS-360, and other reference materials. The results highlight the potential of Dy3+ doped lithium borate glasses as effective radiation shields. Further investigations on chemical combinations and Dy2O3 doping concentrations are warranted to fabricate glasses with enhanced properties. 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved. -
Bismuth (III) oxide decorated graphene oxide filled epoxy nanocomposites: thermo-mechanical and photon attenuation properties
In this study, bismuth (III) oxide (Bi2O3) decorated graphene oxide (GO) nanocomposites were employed as novel radioprotective fillers in the epoxy matrix. Decoration of GO with Bi2O3 would transform it as carrier for Bi2O3 particles, thereby enhancing the thermo-mechanical and radiation shielding properties of the epoxy composites through effective filler distribution. Structural and compositional studies confirmed the successful decoration of Bi2O3 on the surface of GO. Thereupon, epoxy composites containing decorated fillers at different loadings (5, 10 and 15 wt%) were synthesized using solution casting technique. The correlation between surface decoration and filler loading was systematically examined as function of thermo-mechanical, viscoelastic and radiation shielding properties of the composites. These nanocomposites displayed good thermal resistance (~ 450 C), high glass transition temperature (~ 136 C), elastic modulus (~ 4.36 GPa) and storage modulus, thereby confirming the improved dispersion and better interfacial adhesion in the composites. The formation of continuous filler network across epoxy matrix formed by decorated fillers significantly improved X-ray and ?-ray shielding properties of epoxy composites in the wide energy range of medical interest (301332 keV). Shielding efficiency of these lowly loaded BGO/epoxy composites were comparable with the composites containing Bi2O3 nanoparticles alone and highly loaded microcomposites. 2022 Japan Society for Composite Materials, Korean Society for Composite Materials and Informa UK Limited, trading as Taylor & Francis Group. -
Thermal, mechanical and ?-ray shielding properties of micro- and nano-Ta2O5 loaded DGEBA epoxy resin composites
In this work, we have investigated the synergistic effect of micro- and nano-Ta2O5 fillers in the epoxy matrix on the thermal, mechanical, and radioprotective properties of the composites. Morphological analysis revealed uniform dispersion of fillers in the matrix. Both the thermal stability and tensile properties of matrices have enhanced in the presence of fillers. Although the nanocomposites showed significantly higher tensile strength and Youngs modulus compared to micro-composites, the enhancement in these properties was predominant at low loadings. Dynamic mechanical analysis indicated good interfacial adhesion and positive reinforcing effect on the matrix even at higher loading (30 wt%) of nano-Ta2O5. ?-Ray attenuation studies performed in the energy range of 0.3561.332 MeV revealed better ?-ray shielding ability of nanocomposites compared to microcomposites at same weight fraction of fillers. In particular, ?-ray attenuation at 0.356 MeV for 30 wt% nano-Ta2O5 loaded epoxy composite was enhanced by around 13% compared to the microcomposite at the same loading. Increased surface-to-volume ratio of nanofillers and consequent increase in matrix-filler adhesion and radiation-matter interaction have manifested in an overall enhancement in the thermal, mechanical, dynamic mechanical, and radiation shielding characteristics of nano-Ta2O5/epoxy composites, proving them as promising ?-ray shields. 2021 Wiley Periodicals LLC. -
Sodium alginate/bismuth (III) oxide composites for ?-ray shielding applications
In the present work, we have explored the efficacy of bismuth (III) oxide (Bi2O3) loaded, calcium ion cross-linked solution cast sodium alginate composite films for radioprotective applications. Calcium ion cross-linking increased the water and chemical resistance, which further improved on introduction of Bi2O3 into the composites. The 40 wt% Bi2O3 loaded films showed good heat resistance with the peak degradation temperature reaching as high as 251C. The Bi2O3 loaded composites showed enhanced tensile strength (TS) and Youngs modulus (YM). Compared to high-modulus polymers like epoxy, high-density polyethylene (HDPE) and poly (vinyl chloride) (PVC), these exhibit relatively greater extent of stretching before breaking. The ?-ray attenuation experiments showed that mass attenuation coefficients of the composites at various ?-ray energies increased with filler loading. These composites are effective in shielding ?-rays from radioactive sources like 137Cs, 22Na, 133Ba, and 60Co that are widely employed in several medical and industrial applications. The overall enhancement in thermal, mechanical, and radiation shielding characteristics of the composites may be attributed to the uniform distribution of the fillers in alginate matrix. These nontoxic sodium alginate/Bi2O3 composites can be used as soft and biodegradable radiation shields, which may be processed to wearable forms. 2020 Wiley Periodicals LLC. -
Synthetic polymer hydrogels as potential tissue phantoms in radiation therapy and dosimetry
The efficacy of synthetic polymers as hydrogel phantoms for radiation therapy and dosimetry has been investigated for photon and charged particle (electron, proton and alpha particle) interactions. Tissue equivalence has been studied in terms of photon mass energy-absorption coefficients, KERMA (kinetic energy released per unit mass), equivalent atomic number and energy absorption build-up factors, relative to human tissues (skin, soft tissue, cortical bone and skeletal muscle), in the energy range 0.015-15 MeV. For charged particle interactions, ratio of effective atomic number is examined for tissue-equivalence in the energy region of 10 keV-1 GeV. Well established theoretical formulations are used for computation of photon mass-energy absorption effective atomic number, electron density and KERMA. Five-parameter geometric progression (G-P) fitting approximation is used to compute the values of energy absorption build-up factors. Effective atomic number for charged particle interaction is determined using logarithmic interpolation method. Using the analytical methodology, it has been revealed that all the selected synthetic polymers have good tissue-equivalence relative to all tissue except cortical bone. In particular, polyglycolic acid (PGA) and poly-lactic-co-glycolic acid (PLGA) prove to be best substitute material for photon interactions. On the other hand, % difference between effective atomic number for charged particle relative to human tissues is found least for polyethylene glycol (PEG) demonstrating adequate tissue-equivalence. Therefore, the present study is expected to be useful to choose most appropriate phantom material for radiation therapy. 2020 IOP Publishing Ltd. -
Nanoparticles as fillers in composites for x-ray and gamma-ray shielding: A review
In last few decades, nanomaterials have gained enormous attention in the scientific industry due to their tunable physico-chemical and biological properties with enhanced performance over their bulk counterparts. In particular, nanoparticles have been extensively investigated for their usefulness in X-ray and gamma-ray shielding applications. Various elements and compounds, with high atomic numbers and effective atomic numbers respectively, have the potential to form nanoparticles that offer remarkable enhancement in the shielding performance. Composites, obtained by doping different nanoparticles into structural matrices (concrete, glass, or polymers), not only possess striking thermo-mechanical properties but also are effective shielding materials to replace conventional lead shields. This review is an attempt to throw light on various aspects of nanoparticles and their influence on shielding effectiveness. The authors also summarize the experimental findings so as to highlight the potential underlying the radiation-matter interaction mechanism in nanostructured systems. Copyright 2023, IGI Global. -
Recent advances in lightweight epoxy-based composites for X-Ray and y-Ray shielding applications
Rapidly advancing technologies in the nuclear industry have led to the increased use of X-rays and ?-rays in our day-to-day life. They have emerged to be an integral part of several industries including medical diagnostics and imaging, nuclear medicine, reactor research facilities, industrial gauging, agricultural irradiation, geological exploration and security purposes. However, considering the adverse effects of prolonged exposure to these radiations on human health, this is also a cause of concern for mankind and radiation shielding and protection have become issues of paramount importance. In the search for alternatives to conventional shielding materials such as lead, metals, glass composites, ceramics and concretes, epoxy-based composites have emerged as promising X-ray and ?-ray shields. Material properties like high mechanical and bonding strength, high temperature resistance, low electrical conductivity and thermal expansion coefficients, dielectric constant with minimal shrinking stress and lightweight structure render epoxy composites to be particularly suitable for structural applications. Epoxy composites incorporated with fillers/additives such as inorganic metal oxides, carbon fibers, clay and carbon nanotubes are an emerging class of high-performance materials. The primary focus of this article is to present a detailed review on the recent research directed towards developing epoxy-based materials for radiation shielding applications. Influence of filler loading, filler size and interfacial adhesion on microstructural, thermo-mechanical and radioprotective efficacy of epoxy composites are discussed. We present a general overview and propose new possibilities for further research in this direction. 2022 Nova Science Publishers, Inc. -
Preparation and Characterization of Tungsten Carbide/Epoxy Composites for J-Ray Shielding
Polymer composites have attracted considerable attention as potential light weight and cost-effective shielding materials which could be used for applications in nuclear reactors, nuclear waste transportation, as protective cloth/apron for personnel in hospitals, and shielding instruments on-board satellites from space radiations. In this context, we have developed diglycidyl ether of bisphenol A (DGEBA)-based epoxy resin composites loaded with tungsten carbide (WC) for J-ray shielding. Epoxy composites containing different loadings (0, 10, 30 and 50 wt%) of WC were synthesized by room temperature solution casting technique. Structural and morphological studies of the composites were performed using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Thermal and tensile properties of epoxy were enhanced in the presence of WC fillers. Thermogravimetric analysis revealed the major degradation temperature occurring between 430C and 580C for all epoxy/WC composites. The tensile strength and Youngs modulus of the composites enhanced with loading, owing to greater intermolecular reinforcing effect, uniform stress distribution and enhanced energy-absorbing capacity. J-Ray attenuation studies performed in the energy region of 0.356 1.332 MeV using NaI(Tl) detector spectrometer showed the 50 wt% tungsten carbide/epoxy composites to have highest radiation attenuation at all the energies. The overall enhancement in thermal, mechanical, and radiation shielding characteristics of the composites may be attributed to the uniformity in distribution of the fillers in epoxy matrix. These nontoxic tungsten carbide/epoxy composites may be suitable as materials for shielding in radiation environments. 2022 American Institute of Physics Inc.. All rights reserved. -
X-Ray and ?-Ray Shielding Efficiency of Polymer Composites: Choice of Fillers, Effect of Loading and Filler Size, Photon Energy and Multifunctionality
Use of X-rays and ?-rays have become inevitable in medical sectors like radiology, interventional cardiology and diagnostic imaging, radiation physics laboratories, nuclear reactors and accelerator facilities. As radiation exposures above permitted levels pose potential risk to personnel working in close proximity to these facilities, protective measures aimed at reducing the exposure for safeguarding against harmful effects of ionizing radiations are essential. Traditionally, lead and lead based materials have been used as efficient radiation shielding materials owing to the high atomic number and high density of lead. Presently, use of lead is discouraged due to its heavy weight, toxicity and long-term effects on the environment. Consequently, the last two decades have seen research on light weight and cost-effective polymer composites with appropriate additives, having good workability, high specific strength, thermo-chemical stability and radiation shielding efficacy, gaining momentum. This article gives an overview of the state-of-the-art polymer composites reinforced with different fillers studied for their use as effective radiation shields. Here, we summarize the recent advancement and current trends in polymer composites-based radiation shields highlighting the different approaches adopted, choice of polymer/fillers, shielding effectiveness in terms of either linear and/or mass attenuation coefficients, for those who venture into radiation research and development. 2022 Taylor & Francis Group, LLC. -
Enhanced visible light induced dye degradation and antibacterial activities of ZnO/NiO nanocomposite synthesized using Clitoria ternatea flower extract
In this study, ZnO/NiO Nanocomposites (NCs) were prepared using a rapid, simple and eco-friendly green synthesis method using medicinal flower extract of Clitoria ternatea and their visible light assisted dye degradation and antibacterial properties were investigated. The synthesised ZnO/NiO NCs were characterised by ultravioletvisible (UVVis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), High resolution transmission electron microscopy (TEM) and Selected area electron diffraction (SAED) studies. XRD results revealed that ZnO/NiO NCs exhibit hexagonal wurtzite and cubic crystal structure with an average crystallite size of 18 nm. HRTEM images revealed roughly spherical and hexagonal morphology with an average particle size of 23 nm. The antibacterial activity of ZnO/NiO NCs examined against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria using well diffusion method indicated significant antibacterial activity. The photocatalytic activity of the ZnO/NiO NCs showed 83.4 % and 84.4 % of dye degradation efficiency, respectively against Bromophenol Blue (BPB) and Crystal Violet (CV) dye for 150 min under sun light irradiation. The result shows that the ZnO/NiO NCs investigated in this study exhibited a strong potential agent and was successful in the removal of dye from wastewater. 2022 Elsevier B.V. -
A simple software for swift computation of photon and charged particle interaction parameters: PAGEX
PAGEX is a compact and user-friendly cross-platform software developed for swift computation of photon (X-ray and ?-ray) and charged particle interaction parameters for various applications. It is designed based on well-established theoretical formulations and computational techniques integrating various Python packages to effectively calculate parameters such as partial/total photon interaction cross-sections and mass attenuation coefficients, charged particle mass stopping powers and cross-sections, effective atomic number and electron density, mass-energy absorption coefficient, KERMA and build-up factors over a wide energy range. This tool is capable of generating both tabular and graphical outputs which can be saved in any user desired format. PAGEX has been verified against other widely employed software and databases, demonstrating good agreement. This software which facilitates robust computation is freely available from the authors. 2021 Elsevier Ltd -
Blocking intrusion logic using optimized multi-head convolution in wireless sensor network
Wireless sensor nodes (WSN) combine sensing and communication capabilities in the smallest sensor network component. Sensor nodes have basic networking capabilities, such as wireless connection with other nodes, data storage, and a microcontroller to do basic processing. The intrusion detection problem is well analyzed and there exist numerous techniques to solve this issue but suffer will poor intrusion detection accuracy and a higher false alarm ratio. To overcome this challenge, a novel Intrusion Detection via Salp Swarm Optimization based Deep Learning Algorithm (ID-SODA) has been proposed which classifies intrusion node and non-intrusion node. The proposed ID-SODA technique uses the k-means clustering algorithm to perform clustering. The Salp Swarm Optimization (SSO) technique takes into residual energy, distance, and cost while choosing the cluster head selection (CHS). The CHS is given the input to a multi-head convolutional neural network (MHCNN), which will classify into intrusion node and non-intrusion node. The performance analysis of the suggested ID-SODA is evaluated based on the parameters like accuracy, precision, F1 score, detection rate, recall, false alarm rate, and false negative rate. The suggested ID-SODA achieves an accuracy range of 98.95%. The result shows that the suggested ID-SODA improves the overall accuracy better than 6.56%, 2.94%, and 2.95% in SMOTE, SLGBM, and GWOSVM-IDS respectively. 2023 - IOS Press. All rights reserved. -
Effective atomic number and electron density of some biologically important lipids for electron, proton, alpha particle and photon interactions
X-ray, ?-ray and charged particle interaction parameters of biomolecules are useful in medical diagnosis and radiation therapy as exposure to radiations can cause energy of photons and charged particles to be deposited in body through various interaction processes. With this in view, the effective atomic number (Zeff) and electron density (Neff) of some biologically important lipids for X-ray, ?-ray and charged particle interactions were studied in the energy range 10 keV500 MeV using logarithmic interpolation method. A non-monotonic variation in Zeff values was observed for protons and alpha particles in low and intermediate energy regions respectively whereas a sudden increase in Zeff was observed for electron interaction in higher energy region. Zeff values were maximum in higher energy region for total electron interactions whereas maximum values of Zeff for total alpha particle interactions were at relatively lower energies. Highest Zeff values were found at lower energy region of photoelectric absorption dominance for photon interactions. Variation in Neff seems to be similar to variation in Zeff as they are inter-related. 2020 Elsevier Ltd -
The dharma of Kama: Kamasra's morality of integrated Purusartha
[No abstract available] -
The family strengths of the Lambhanis of Bellary district /
The study titled The Family Strengths of the Lambhanis of Bellary District aimed at identifying and exploring Family Strengths of the Lambhanis their perpetuation. The study was based on the Family Strengths Model using an Interpretivistic Research Philosophy and a Grounded Theory Research Paradigm within a Qualitative Framework. The sample of the study was taken through a key informant. The participants were from Dasarhalli Thanda, Bellary District, Karnataka. They were all adults both men and women. Three Focus Groups were conducted and the interviews were unstructured, data was collected until Data Saturation was reached. The data was recorded/taped, translated and transcripts written. The data gathered was then coded based on the Grounded Theory Method proposed by Strauss and Corbin (1998). -
Streamlined electrochemical harvesting of cobalt and nickel from soft cemented carbide scrap for superior supercapacitors
We propose a complete circular economy and sustainability model from soft cemented carbide scrap to supercapacitor application. An enhanced recovery of cobalt and nickel was observed when deep eutectic solvent was used. A comparative in-situ electrochemical deposition of the recovered metals was done on stainless steel (SS), SS/activated carbon (AC), and SS/AC/polyaniline (PANI). The optimization of electrochemical extraction was carried out by varying voltage, time, and temperature. The surface area and conductive polymer's electronic distribution contributed to different surface morphological deposition of specific metals on them. Unique fluffy particle deposition was observed on the surface as fine grain particles with uniform particle size within 1 m. The fabricated supercapacitors showed the pseudocapacitance behaviour. The presence of metal oxide nanocomposite deposition as the active material is particularly pronounced in the SS/AC/PANI device due to the inclusion of PANI as an active material and its substantial contribution to pseudocapacitance. The higher charge-discharge time of SS/AC/PANI at the same current densities compared to SS/AC may be due to the above-mentioned additional contribution of PANI's quickly reversible redox behavior. Hence, the overall electrochemical extraction from scrap to supercapacitor will undoubtedly lead to achieving the sustainable development goals (SDGs) 2024 -
READING AND ENGAGING WITH KACEN CALLENDERS MOONFLOWER THROUGH INTERSECTIONAL PEDAGOGIES
This chapter argues that privileged perspectives can be decentered using intersectional pedagogies when engaging with literary texts such as Moonflower, a novel that engages children with vital topics relating to race, gender, and mental health. 2024 selection and editorial matter, KaaVonia Hinton and Karen Michele Chandler; individual chapters, the contributors. All rights reserved. -
Canopy removal on satellite images using classification and contrast enhancement
The increasing the usage of satellite remote sensing for a civilian purpose has proved to be the most cost-effective mapping environmental changes with regard to natural resources, particularly in developing countries. Forests as one part of the wildlife of human societies in economic growth and permanency of natural resources in the countries of the world. But because of various details such as the growth of population, progressively varying forest to the other unfitting applications such as agriculture, providing energy and fuel, millions of hectares from the natural means are destroyed every year, and the remainder of the surface changes quantitatively and qualitatively. For better management of the forests, the evolution of forest area and rate of forest concentration should be examined. It is achievable that, there isnt any change in the field of the forest during the time, but the density of forest canopy is changed. Estimation of forest canopy cover has recently become an essential part of the forest. Therefore, the research study is to develop Forest Canopy Remover, which is used to get an accurate result of Forest and deforested area from the satellite earth images. It is used to calculate forest density using vegetation. Then, the changes in area and forest density during a particular period can be distinguished. 2020 IJSTR. -
Energy efficient data collection in sparse sensor networks using multiple Mobile Data Patrons
Wireless sensor networks consist of sensor nodes that can sense the environment and forward the sensed data to the destination. It takes multiple hops for the data to get transmitted from the source to the destination node. Mobile Data Patron is a high energy mobile data collector that collects data from the sensors within sparse networks. In sparse networks, the sensors detect the physical phenomenon, and the MDP is used to collect data generated by the sensors. In existing models, a single MDP is used to collect data from sensors within sparse networks. It requires high amounts of energy for long-range data transmission to the base station. The proposed work uses multiple MDPs to solve the energy depletion problem. The research also focuses on improving the data transfer rate so that the MDPs lose minimal amounts of energy. 2020