Search results for: normalized glandular dose
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1818

Search results for: normalized glandular dose

1698 Influence of Pediococcus Pentasaceus Isolate “Dadih” (Buffalo Milk Fermended in Bamboo) the Bowel Frequence, Secretory Immunoglobulin a Level and Height of Ileum Villi of the Mice EPEC Induced Diarrhea

Authors: Endang Purwati Rahayuningsih

Abstract:

The aim of this study is Enteropathogenic Eschericia coli O157 (EPEC) is one of the pathogen that can cause inflamation and damage intestinal mucosa, which is leading diarrhea. Inflamation in the intestinal mucosa proved by the presence of secretory Immunoglobulin A (sIgA) on the feces. Isolate dadih is Pediococcus pentosaceus (P. pentosaceus) as a probiotic lactic acid bacteria (LAB) is very usefull to improve sIgA and intestinal mucosa. The objective, to determine the dose and duration administration of P. pentosaceus for bowel frequence, sIgA level and height of illeum villi in mice EPEC-induced diarrhea. Method, using Complete Randomized design studies in mice EPEC-induced diarrhea. Mice was classified into 2 factors. A factor (dose of probiotic) and B factor (duration of probiotic observation) consisted of 0 hour, 12 hours, 24 hours and 36 hours. A factor consisted of negative control, positive control (mice induced by EPEC) and 3 different dose experimental mice. The results were a very significant interaction between dose and duration administration of P. pentosaceus. Mean of the most frequent defecation of mice EPEC-induced was 55 graetly reduced into 12 ,after 24 hours administration P. pentosaceus dose 2 x 1010 cfu/g, Mean of sIgA level of mice induced EPEC was 1,60 μg/ml, very significant different (p<0,01). Mean of sIgA level after 24 administration P. pentosaceus dose 2 x 1010cfu/g was 2,65 μg/ml. Mean of height of illeum villi after induced EPEC 53,04 μm with very significant different after 24 hours administration P. pentosaceus dose 2 x 1010cfu/g (142,881μm). This study concluded that P. pentosaceus dose 2 x 1010cfu/g after 24 hours is very beneficial to reduced bowel frequence, increase sIgA level and improve the height illeum villi of mice EPEC-induced diarrhea.

Keywords: Pediococcus pentosaceus, sIgA, enteropathogenic Eschericia coli O157, diarrhea, illeum villi

Procedia PDF Downloads 477
1697 Dosimetric Comparison of Conventional Optimization Methods with Inverse Planning Simulated Annealing Technique

Authors: Shraddha Srivastava, N. K. Painuly, S. P. Mishra, Navin Singh, Muhsin Punchankandy, Kirti Srivastava, M. L. B. Bhatt

Abstract:

Various optimization methods used in interstitial brachytherapy are based on dwell positions and dwell weights alteration to produce dose distribution based on the implant geometry. Since these optimization schemes are not anatomy based, they could lead to deviations from the desired plan. This study was henceforth carried out to compare anatomy-based Inverse Planning Simulated Annealing (IPSA) optimization technique with graphical and geometrical optimization methods in interstitial high dose rate brachytherapy planning of cervical carcinoma. Six patients with 12 CT data sets of MUPIT implants in HDR brachytherapy of cervical cancer were prospectively studied. HR-CTV and organs at risk (OARs) were contoured in Oncentra treatment planning system (TPS) using GYN GEC-ESTRO guidelines on cervical carcinoma. Three sets of plans were generated for each fraction using IPSA, graphical optimization (GrOPT) and geometrical optimization (GOPT) methods. All patients were treated to a dose of 20 Gy in 2 fractions. The main objective was to cover at least 95% of HR-CTV with 100% of the prescribed dose (V100 ≥ 95% of HR-CTV). IPSA, GrOPT, and GOPT based plans were compared in terms of target coverage, OAR doses, homogeneity index (HI) and conformity index (COIN) using dose-volume histogram (DVH). Target volume coverage (mean V100) was found to be 93.980.87%, 91.341.02% and 85.052.84% for IPSA, GrOPT and GOPT plans respectively. Mean D90 (minimum dose received by 90% of HR-CTV) values for IPSA, GrOPT and GOPT plans were 10.19 ± 1.07 Gy, 10.17 ± 0.12 Gy and 7.99 ± 1.0 Gy respectively, while D100 (minimum dose received by 100% volume of HR-CTV) for IPSA, GrOPT and GOPT plans was 6.55 ± 0.85 Gy, 6.55 ± 0.65 Gy, 4.73 ± 0.14 Gy respectively. IPSA plans resulted in lower doses to the bladder (D₂

Keywords: cervical cancer, HDR brachytherapy, IPSA, MUPIT

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1696 Acoustic Echo Cancellation Using Different Adaptive Algorithms

Authors: Hamid Sharif, Nazish Saleem Abbas, Muhammad Haris Jamil

Abstract:

An adaptive filter is a filter that self-adjusts its transfer function according to an optimization algorithm driven by an error signal. Because of the complexity of the optimization algorithms, most adaptive filters are digital filters. Adaptive filtering constitutes one of the core technologies in digital signal processing and finds numerous application areas in science as well as in industry. Adaptive filtering techniques are used in a wide range of applications, including adaptive noise cancellation and echo cancellation. Acoustic echo cancellation is a common occurrence in today’s telecommunication systems. The signal interference caused by acoustic echo is distracting to both users and causes a reduction in the quality of the communication. In this paper, we review different techniques of adaptive filtering to reduce this unwanted echo. In this paper, we see the behavior of techniques and algorithms of adaptive filtering like Least Mean Square (LMS), Normalized Least Mean Square (NLMS), Variable Step-Size Least Mean Square (VSLMS), Variable Step-Size Normalized Least Mean Square (VSNLMS), New Varying Step Size LMS Algorithm (NVSSLMS) and Recursive Least Square (RLS) algorithms to reduce this unwanted echo, to increase communication quality.

Keywords: adaptive acoustic, echo cancellation, LMS algorithm, adaptive filter, normalized least mean square (NLMS), variable step-size least mean square (VSLMS)

Procedia PDF Downloads 80
1695 Application of Rapid Eye Imagery in Crop Type Classification Using Vegetation Indices

Authors: Sunita Singh, Rajani Srivastava

Abstract:

For natural resource management and in other applications about earth observation revolutionary remote sensing technology plays a significant role. One of such application in monitoring and classification of crop types at spatial and temporal scale, as it provides latest, most precise and cost-effective information. Present study emphasizes the use of three different vegetation indices of Rapid Eye imagery on crop type classification. It also analyzed the effect of each indices on classification accuracy. Rapid Eye imagery is highly demanded and preferred for agricultural and forestry sectors as it has red-edge and NIR bands. The three indices used in this study were: the Normalized Difference Vegetation Index (NDVI), the Green Normalized Difference Vegetation Index (GNDVI), and the Normalized Difference Red Edge Index (NDRE) and all of these incorporated the Red Edge band. The study area is Varanasi district of Uttar Pradesh, India and Radial Basis Function (RBF) kernel was used here for the Support Vector Machines (SVMs) classification. Classification was performed with these three vegetation indices. The contribution of each indices on image classification accuracy was also tested with single band classification. Highest classification accuracy of 85% was obtained using three vegetation indices. The study concluded that NDRE has the highest contribution on classification accuracy compared to the other vegetation indices and the Rapid Eye imagery can get satisfactory results of classification accuracy without original bands.

Keywords: GNDVI, NDRE, NDVI, rapid eye, vegetation indices

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1694 Gamma Irradiation Effects on the Magnetic Properties of Hard Ferrites

Authors: F. Abbas Pour Khotbehsara, B. Salehpour, A. Kianvash

Abstract:

Many industrial materials like magnets need to be tested for the radiation environment expected at linear colliders (LC) where the accelerator and detectors will be subjected to large influences of beta, neutron and gamma’s over their life Gamma irradiation of the permanent sample magnets using a 60Co source was investigated up to an absorbed dose of 700Mrad shows a negligible effect on some magnetic properties of Nd-Fe-B. In this work, it has been tried to investigate the change of some important properties of Barium hexa ferrite. Results showed little decreases of magnetic properties at doses rang of 0.5 to 2.5 Mrad. But at the gamma irradiation dose up to 10 Mrad it is showed a few increase of properties. Also study of gamma irradiation of Nd-Fe-B showed considerably increase of magnetic properties.

Keywords: gamma ray irradiation, hard ferrite, magnetic coefficient, magnetic material, radiation dose

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1693 Assessment of Dose: Area Product of Common Radiographic Examinations in Selected Southern Nigerian Hospitals

Authors: Lateef Bamidele

Abstract:

Over the years, radiographic examinations are the most used diagnostic tools in the Nigerian health care system, but most diagnostic examinations carried out do not have records of patient doses. Lack of adequate information on patient doses has been a major hindrance in quantifying the radiological risk associated with radiographic examinations. This study aimed at estimating dose–area product (DAP) of patient examined in X-Ray units in selected hospitals in Southern Nigeria. The standard projections selected are chest posterior-anterior (PA), abdomen anterior-posterior (AP), pelvis AP, pelvis lateral (LAT), skull AP/PA, skull LAT, lumbar spine AP, lumbar spine, LAT. Measurement of entrance surface dose (ESD) was carried out using thermoluminescent dosimeter (TLD). Measured ESDs were converted into DAP using the beam area of patients. The results show that the mean DAP ranged from 0.17 to 18.35 Gycm². The results obtained in this study when compared with those of NRPB-HPE were found to be higher. These are an indication of non optimization of operational conditions.

Keywords: dose–area product, radiographic examinations, patient doses, optimization

Procedia PDF Downloads 176
1692 Assessment of Land Surface Temperature Using Satellite Remote Sensing

Authors: R. Vidhya, M. Navamuniyammal M. Sivakumar, S. Reeta

Abstract:

The unplanned urbanization affects the environment due to pollution, conditions of the atmosphere, decreased vegetation and the pervious and impervious soil surface. Considered to be a cumulative effect of all these impacts is the Urban Heat Island. In this paper, the urban heat island effect is studied for the Chennai city, TamilNadu, South India using satellite remote sensing data. LANDSAT 8 OLI and TIRS DATA acquired on 9th September 2014 were used to Land Surface Temperature (LST) map, vegetation fraction map, Impervious surface fraction, Normalized Difference Water Index (NDWI), Normalized Difference Building Index (NDBI) and Normalized Difference Vegetation Index (NDVI) map. The relationship among LST, Vegetation fraction, NDBI, NDWI, and NDVI was calculated. The Chennai city’s Urban Heat Island effect is significant, and the results indicate LST has strong negative correlation with the vegetation present and positive correlation with NDBI. The vegetation is the main factor to control urban heat island effect issues in urban area like Chennai City. This study will help in developing measures to land use planning to reduce the heat effects in urban area based on remote sensing derivatives.

Keywords: land surface temperature, brightness temperature, emissivity, vegetation index

Procedia PDF Downloads 275
1691 Supplier Selection by Bi-Objectives Mixed Integer Program Approach

Authors: K.-H. Yang

Abstract:

In the past, there was a lot of excellent research studies conducted on topics related to supplier selection. Because the considered factors of supplier selection are complicated and difficult to be quantified, most researchers deal supplier selection issues by qualitative approaches. Compared to qualitative approaches, quantitative approaches are less applicable in the real world. This study tried to apply the quantitative approach to study a supplier selection problem with considering operation cost and delivery reliability. By those factors, this study applies Normalized Normal Constraint Method to solve the dual objectives mixed integer program of the supplier selection problem.

Keywords: bi-objectives MIP, normalized normal constraint method, supplier selection, quantitative approach

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1690 Normalized P-Laplacian: From Stochastic Game to Image Processing

Authors: Abderrahim Elmoataz

Abstract:

More and more contemporary applications involve data in the form of functions defined on irregular and topologically complicated domains (images, meshs, points clouds, networks, etc). Such data are not organized as familiar digital signals and images sampled on regular lattices. However, they can be conveniently represented as graphs where each vertex represents measured data and each edge represents a relationship (connectivity or certain affinities or interaction) between two vertices. Processing and analyzing these types of data is a major challenge for both image and machine learning communities. Hence, it is very important to transfer to graphs and networks many of the mathematical tools which were initially developed on usual Euclidean spaces and proven to be efficient for many inverse problems and applications dealing with usual image and signal domains. Historically, the main tools for the study of graphs or networks come from combinatorial and graph theory. In recent years there has been an increasing interest in the investigation of one of the major mathematical tools for signal and image analysis, which are Partial Differential Equations (PDEs) variational methods on graphs. The normalized p-laplacian operator has been recently introduced to model a stochastic game called tug-of-war-game with noise. Part interest of this class of operators arises from the fact that it includes, as particular case, the infinity Laplacian, the mean curvature operator and the traditionnal Laplacian operators which was extensiveley used to models and to solve problems in image processing. The purpose of this paper is to introduce and to study a new class of normalized p-Laplacian on graphs. The introduction is based on the extension of p-harmonious function introduced in as discrete approximation for both infinity Laplacian and p-Laplacian equations. Finally, we propose to use these operators as a framework for solving many inverse problems in image processing.

Keywords: normalized p-laplacian, image processing, stochastic game, inverse problems

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1689 Comparison of the Dose Reached to the Rectum and Bladder in Two Treatment Methods by Tandem and Ovoid and Tandem and Ring in the High Dose Rate Brachytherapy of Cervical Cancer

Authors: Akbar Haghzadeh Saraskanroud, Amir Hossein Yahyavi Zanjani, Niloofar Kargar, Hanieh Ahrabi

Abstract:

Cervical cancer refers to an unusual growth of cells in the cervix. The cervix is the lower part of the uterus, which connects to the vagina. Various risk factors such as human papillomavirus (HPV), having a weakened immune system, smoking or breathing in secondhand smoke, reproductive factors, and obesity play important roles in causing most cervical cancers. When cervical cancer happens, surgery is often the first treatment option to remove it. Other treatments might include chemotherapy and targeted therapy medicines. Radiation therapy with high-energy photon beams also may be used. Sometimes combined treatment, including radiation with low-dose chemotherapy, was applied. Intracavitary brachytherapy is an integral part of radiotherapy for locally advanced gynecologic malignancies such as cervical cancer. In the treatment of cervical cancer, there are different tools for doing brachytherapy. Two combinations of different applicators for this purpose are Tandem and Ovoid and Tandem and Ring. This study evaluated the dose differences between these two methods in the organs at risk of the rectum, sigmoid, and bladder. In this study, the treatment planswere simulated by the Oncentra treatment planning system and Tandem, Ovid, and Rings of different sizes. CT scan images of 23 patients were treated with HDR_BT Elekta Flexitron system were used for this study. Contouring of HR-CTV, rectum and bladder was performed for all patients. Then, the received dose of 0.1 and 0.2cc volumes of organs at risk were obtained and compared for these two methods: T-Ovoid and T-Ring. By doing investigations and dose measurements of points A and B and the volumes specified by ICRU, it seems that when comparing ring and ovoid to tandem and ovoid, the total dose to the rectum was lower by about 11%, and the bladder was 7%. In the case of HR CTV, this comparison showed that this ratio is about 7% better. Figure 1 shows the amount of decrease in rectum dose in the T-Ring method compared to T-Ovoid. Figure 2 indicates the amount of decrease in bladder dose in the T-Ring method compared to T-Ovoid. Finally, figure 3 illustrates the amount of HR-CTV coverage in the T-Ring method compared to the T-Ovoid.

Keywords: cervical cancer, brachytherapy, rectum, tandem and ovoid, tandem and ring.

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1688 Low-Dose Chest Computed Tomography Can Help in Differential Diagnosis of Asthma–COPD Overlap Syndrome in Children

Authors: Frantisek Kopriva, Kamila Michalkova, Radim Dudek, Jana Volejnikova

Abstract:

Rationale: Diagnostic criteria of asthma–COPD overlap syndrome (ACOS) are controversial in pediatrics. Emphysema is characteristic of COPD and usually does not occur in typical asthma; its presence in patients with asthma suggests the concurrence with COPD. Low-dose chest computed tomography (CT) allows a non-invasive assessment of the lung tissue structure. Here we present CT findings of emphysematous changes in a child with ACOS. Patient and Methods: In a 6-year-old boy, atopy was confirmed by a skin prick test using common allergen extracts (grass and tree pollen, house dust mite, molds, cat, dog; manufacturer Stallergenes Greer, London, UK), where reactions over 3 mm were considered positive. Treatment with corticosteroids was started during the course of severe asthma. At 12 years of age, his spirometric parameters deteriorated despite treatment adjustment (VC 1.76 L=85%, FEV1 1.13 L=67%, TI%VCmax 64%, MEF25 19%, TLC 144%) and the bronchodilator test became negative. Results: Low-dose chest CT displayed irregular regions with increased radiolucency of pulmonary parenchyma (typical for hyperinflation in emphysematous changes) in both lungs. This was in accordance with the results of spirometric examination. Conclusions: ACOS is infrequent in children. However, low-dose chest CT scan can be considered to confirm this diagnosis or eliminate other diagnoses when the clinical condition is deteriorating and treatment response is poor.

Keywords: child, asthma, low-dose chest CT, ACOS

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1687 How Geant4 Hadronic Models Handle Tracking of Pion Particles Resulting from Antiproton Annihilation

Authors: M. B. Tavakoli, R. Reiazi, M. M. Mohammadi, K. Jabbari

Abstract:

From 2003, AD4/ACE experiment in CERN tried to investigate different aspects of antiproton as a new modality in particle therapy. Because of lack of reliable absolute dose measurements attempts to find out the radiobiological characteristics of antiproton have not reached to a reasonable result yet. From the other side, application of Geant4 in medical approaches is increased followed by Geant4-DNA project which focuses on using this code to predict radiation effects in the cellular scale. This way we can exploit Geant4-DNA results for antiproton. Unfortunately, previous studies showed there are serious problem in simulating an antiproton beam using Geant4. Since most of the problem was in the Bragg peak region which antiproton annihilates there, in this work we tried to understand if the problem came from the way in which Geant4 handles annihilation products especially pion particles. This way, we can predict the source of the dose discrepancies between Geant4 simulations and dose measurements done in CERN.

Keywords: Geant4, antiproton, annihilation, pion plus, pion minus

Procedia PDF Downloads 657
1686 Toxicities associated with EBRT and Brachytherapy for Intermediate and High Risk Prostate Cancer, Correlated with Intra-operative Dosing

Authors: Rebecca Dunne, Cormac Small, Geraldine O'Boyle, Nazir Ibrahim, Anisha

Abstract:

Prostate cancer is the most common cancer among men, excluding non-melanoma skin cancers. It is estimated that approximately 12% of men will develop prostate cancer during their lifetime. Patients with intermediate, high risk, and very-high risk prostate cancer often undergo a combination of radiation treatments. These treatments include external beam radiotherapy with a low-dose rate or high-dose rate brachytherapy boost, often with concomitant androgen deprivation therapy. The literature on follow-up of patients that receive brachytherapy is scarce, particularly follow-up of patients that undergo high-dose rate brachytherapy. This retrospective study aims to investigate the biochemical failure and toxicities associated with triple therapy and external beam radiotherapy given in combination with brachytherapy. Reported toxicities and prostate specific antigen (PSA) were retrospectively evaluated in eighty patients that previously underwent external beam radiotherapy with a low-dose rate or high dose-rate brachytherapy boost. The severity of toxicities were correlated with intra-operative dosing during brachytherapy on ultrasound and CT scan. The results of this study will provide further information for clinicians and patients when considering treatment options.

Keywords: toxicities, combination, brachytherapy, intra-operative dosing, biochemical failure

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1685 Optimizing the Doses of Chitosan/Tripolyphosphate Loaded Nanoparticles of Clodinofop Propargyl and Fenoxaprop-P-Ethyl to Manage Avena Fatua L.: An Environmentally Safer Alternative to Control Weeds

Authors: Muhammad Ather Nadeem, Bilal Ahmad Khan, Hussam F. Najeeb Alawadi, Athar Mahmood, Aneela Nijabat, Tasawer Abbas, Muhammad Habib, Abdullah

Abstract:

The global prevalence of Avena fatua infestation poses a significant challenge to wheat sustainability. While chemical control stands out as an efficient and rapid way to control weeds, concerns over developing resistance in weeds and environmental pollution have led to criticisms of herbicide use. Consequently, this study was designed to address these challenges through the chemical synthesis, characterization, and optimization of chitosan-based nanoparticles containing clodinofop Propargyl and fenoxaprop-P-ethyl for the effective management of A. fatua. Utilizing the ionic gelification technique, chitosan-based nanoparticles of clodinofop Propargyl and fenoxaprop-P-ethyl were prepared. These nanoparticles were applied at the 3-4 leaf stage of Phalaris minor weed, applying seven altered doses. These nanoparticles were applied at the 3-4 leaf stage of Phalaris minor weed, applying seven altered doses (D0 (Check weeds), D1 (Recommended dose of traditional-herbicide (TH), D2 (Recommended dose of Nano-herbicide (NPs-H)), D3 (NPs-H with 05-fold lower dose), D4 ((NPs-H) with 10-fold lower dose), D5 (NPs-H with 15-fold lower dose), and D6 (NPs-H with 20-fold lower dose)). Characterization of the chitosan-containing herbicide nanoparticles (CHT-NPs) was conducted using FT-IR analysis, demonstrating a perfect match with standard parameters. UV–visible spectrum further revealed absorption peaks at 310 nm for NPs of clodinofop propargyl and at 330 nm for NPs of fenoxaprop-p-ethyl. This research aims to contribute to sustainable weed management practices by addressing the challenges associated with chemical herbicide use. The application of chitosan-based nanoparticles (CHT-NPs) containing fenoxaprop-P-ethyl and clodinofop-propargyl at the recommended dose of the standard herbicide resulted in 100% mortality and visible injury to weeds. Surprisingly, when applied at a lower dose with 5-folds, these chitosan-containing nanoparticles of clodinofop Propargyl and fenoxaprop-P-ethyl demonstrated extreme control efficacy. Furthermore, at a 10-fold lower dose compared to standard herbicides and the recommended dose of clodinofop-propargyl and fenoxaprop-P-ethyl, the chitosan-based nanoparticles exhibited comparable effects on chlorophyll content, visual injury (%), mortality (%), plant height (cm), fresh weight (g), and dry weight (g) of A. fatua. This study indicates that chitosan/tripolyphosphate-loaded nanoparticles containing clodinofop-propargyl and fenoxaprop-P-ethyl can be effectively utilized for the management of A. fatua at a 10-fold lower dose, highlighting their potential for sustainable and efficient weed control.

Keywords: mortality, chitosan-based nanoparticles, visual injury, chlorophyl contents, 5-fold lower dose.

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1684 Measurement of 238U, 232Th and 40K in Soil Samples Collected from Coal City Dhanbad, India

Authors: Zubair Ahmad

Abstract:

Specific activities of the natural radionuclides 238U, 232Th and 40K were measured by using γ - ray spectrometric technique in soil samples collected from the city of Dhanbad, which is located near coal mines. Mean activity values for 238U, 232Th and 40K were found to be 60.29 Bq/kg, 64.50 Bq/kg and 481.0 Bq/kg, respectively. Mean radium equivalent activity, absorbed dose rate, outdoor dose, external hazard index, internal hazard index, for the area under study were determined as 189.53 Bq/kg, 87.21 nGy/h, 0.37 mSv/y, 0.52 and 0.64, respectively. The annual effective dose to the general public was found 0.44 mSv/y. This value lies well below the limit of 1 mSv/y as recommended by International Commission on Radiological Protection. Measured values were found safe for environment and public health.

Keywords: coal city Dhanbad, gamma-ray spectroscopy, natural radioactivity, soil samples

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1683 Predicting Dose Level and Length of Time for Radiation Exposure Using Gene Expression

Authors: Chao Sima, Shanaz Ghandhi, Sally A. Amundson, Michael L. Bittner, David J. Brenner

Abstract:

In a large-scale radiologic emergency, potentially affected population need to be triaged efficiently using various biomarkers where personal dosimeters are not likely worn by the individuals. It has long been established that radiation injury can be estimated effectively using panels of genetic biomarkers. Furthermore, the rate of radiation, in addition to dose of radiation, plays a major role in determining biological responses. Therefore, a better and more accurate triage involves estimating both the dose level of the exposure and the length of time of that exposure. To that end, a large in vivo study was carried out on mice with internal emitter caesium-137 (¹³⁷Cs). Four different injection doses of ¹³⁷Cs were used: 157.5 μCi, 191 μCi, 214.5μCi, and 259 μCi. Cohorts of 6~7 mice from the control arm and each of the dose levels were sacrificed, and blood was collected 2, 3, 5, 7 and 14 days after injection for microarray RNA gene expression analysis. Using a generalized linear model with penalized maximum likelihood, a panel of 244 genes was established and both the doses of injection and the number of days after injection were accurately predicted for all 155 subjects using this panel. This has proven that microarray gene expression can be used effectively in radiation biodosimetry in predicting both the dose levels and the length of exposure time, which provides a more holistic view on radiation exposure and helps improving radiation damage assessment and treatment.

Keywords: caesium-137, gene expression microarray, multivariate responses prediction, radiation biodosimetry

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1682 Radon Concentration in the Water Samples of Hassan District, Karnataka, India

Authors: T. S. Shashikumar

Abstract:

Radon is a radioactive gas emitted from radium, a daughter product of uranium that occurs naturally in rocks and soil. Radon, together with its decay products, emits alpha particles that can damage lung tissue. The activity concentration of 222Ra has been analyzed in water samples collected from borewells and rivers in and around Hassan city, Karnataka State, India. The measurements were performed by Emanometry technique. The concentration of 222Rn in borewell waters varies from 18.49±1.89 to 397.26±12.3 Bql-1 with geometric mean 120.48±12.87 Bql-1 and in river waters it varies from 92.63±9.31 to 93.98±9.51 Bql-1 with geometric mean of 93.16±9.33 Bql-1. In the present study, the radon concentrations are higher in Adarshanagar and Viveka Nagar which are found to be 397.26±12.3 Bql-1 and 325.78±32.56 Bql-1. Most of the analysed samples show a 222Rn concentration more than 100 Bql-1 and this can be attributed to the geology of the area where the ground waters are located, which is predominantly of granitic characteristic. The average inhalation dose and ingestion dose in the borewell water are found to be 0.405 and 0.033 µSvy-1; and in river water it is found to be 0.234 and 0.019 µSvy-1, respectively. The average total effective dose rate in borewell waters and river waters are found to be 0.433 and 0.253 µSvy-1, which does not cause any health risk to the population of Hassan region.

Keywords: borewell, effective dose, emanometry, 222Rn

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1681 Analyzing Land use change and its impacts on the Urban Environment in a Fast Growing Metropolitan City of Pakistan

Authors: Muhammad Nasar-u-Minallah, Dagmar Haase, Salman Qureshi

Abstract:

In a rapidly growing developing country cities are becoming more urbanized leading to modifications in urban climate. Rapid urbanization, especially unplanned urban land expansion, together with climate change has a profound impact on the urban settlement and urban thermal environment. Cities, particularly Pakistan are facing remarkably environmental issues and uneven development, and thus it is important to strengthen the investigation of urban environmental pressure brought by land-use changes and urbanization. The present study investigated the long term modification of the urban environment by urbanization utilizing Spatio-temporal dynamics of land-use change, urban population data, urban heat islands, monthly maximum, and minimum temperature of thirty years, multi remote sensing imageries, and spectral indices such as Normalized Difference Built-up Index and Normalized Difference Vegetation Index. The results indicate rapid growth in an urban built-up area and a reduction in vegetation cover in the last three decades (1990-2020). A positive correlation between urban heat islands and Normalized Difference Built-up Index, whereas a negative correlation between urban heat islands and the Normalized Difference Vegetation Index clearly shows how urbanization is affecting the local environment. The increase in air and land surface temperature temperatures is dangerous to human comfort. Practical approaches, such as increasing the urban green spaces and proper planning of the cities, have been suggested to help prevent further modification of the urban thermal environment by urbanization. The findings of this work are thus important for multi-sectorial use in the cities of Pakistan. By taking into consideration these results, the urban planners, decision-makers, and local government can make different policies to mitigate the urban land use impacts on the urban thermal environment in Pakistan.

Keywords: land use, urban environment, local climate, Lahore

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1680 Estimation of Shear Wave Velocity from Cone Penetration Test for Structured Busan Clays

Authors: Vinod K. Singh, S. G. Chung

Abstract:

The degree of structuration of Busan clays at the mouth of Nakdong River mouth was highly influenced by the depositional environment, i.e., flow of the river stream, marine regression, and transgression during the sedimentation process. As a result, the geotechnical properties also varies along the depth with change in degree of structuration. Thus, the in-situ tests such as cone penetration test (CPT) could not be used to predict various geotechnical properties properly by using the conventional empirical methods. In this paper, the shear wave velocity (Vs) was measured from the field using the seismic dilatometer. The Vs was also measured in the laboratory from high quality undisturbed and remolded samples using bender element method to evaluate the degree of structuration. The degree of structuration was quantitatively defined by the modulus ratio of undisturbed to remolded soil samples which is found well correlated with the normalized void ratio (e0/eL) where eL is the void ratio at the liquid limit. It is revealed that the empirical method based on laboratory results incorporating e0/eL can predict Vs from the field more accurately. Thereafter, the CPT based empirical method was developed to estimate the shear wave velocity taking the effect of structuration in the consideration. The developed method was found to predict shear wave velocity reasonably for Busan clays.

Keywords: level of structuration, normalized modulus, normalized void ratio, shear wave velocity, site characterization

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1679 Comparative Evaluation of Pharmacologically Guided Approaches (PGA) to Determine Maximum Recommended Starting Dose (MRSD) of Monoclonal Antibodies for First Clinical Trial

Authors: Ibraheem Husain, Abul Kalam Najmi, Karishma Chester

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First-in-human (FIH) studies are a critical step in clinical development of any molecule that has shown therapeutic promise in preclinical evaluations, since preclinical research and safety studies into clinical development is a crucial step for successful development of monoclonal antibodies for guidance in pharmaceutical industry for the treatment of human diseases. Therefore, comparison between USFDA and nine pharmacologically guided approaches (PGA) (simple allometry, maximum life span potential, brain weight, rule of exponent (ROE), two species methods and one species methods) were made to determine maximum recommended starting dose (MRSD) for first in human clinical trials using four drugs namely Denosumab, Bevacizumab, Anakinra and Omalizumab. In our study, the predicted pharmacokinetic (pk) parameters and the estimated first-in-human dose of antibodies were compared with the observed human values. The study indicated that the clearance and volume of distribution of antibodies can be predicted with reasonable accuracy in human and a good estimate of first human dose can be obtained from the predicted human clearance and volume of distribution. A pictorial method evaluation chart was also developed based on fold errors for simultaneous evaluation of various methods.

Keywords: clinical pharmacology (CPH), clinical research (CRE), clinical trials (CTR), maximum recommended starting dose (MRSD), clearance and volume of distribution

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1678 Accuracy of Computed Tomography Dose Monitor Values: A Multicentric Study in India

Authors: Adhimoolam Saravana Kumar, K. N. Govindarajan, B. Devanand, R. Rajakumar

Abstract:

The quality of Computed Tomography (CT) procedures has improved in recent years due to technological developments and increased diagnostic ability of CT scanners. Due to the fact that CT doses are the peak among diagnostic radiology practices, it is of great significance to be aware of patient’s CT radiation dose whenever a CT examination is preferred. CT radiation dose delivered to patients in the form of volume CT dose index (CTDIvol) values, is displayed on scanner monitors at the end of each examination and it is an important fact to assure that this information is accurate. The objective of this study was to estimate the CTDIvol values for great number of patients during the most frequent CT examinations, to study the comparison between CT dose monitor values and measured ones, as well as to highlight the fluctuation of CTDIvol values for the same CT examination at different centres and scanner models. The output CT dose indices measurements were carried out on single and multislice scanners for available kV, 5 mm slice thickness, 100 mA and FOV combination used. The 100 CT scanners were involved in this study. Data with regard to 15,000 examinations in patients, who underwent routine head, chest and abdomen CT were collected using a questionnaire sent to a large number of hospitals. Out of the 15,000 examinations, 5000 were head CT examinations, 5000 were chest CT examinations and 5000 were abdominal CT examinations. Comprehensive quality assurance (QA) was performed for all the machines involved in this work. Followed by QA, CT phantom dose measurements were carried out in South India using actual scanning parameters used clinically by the hospitals. From this study, we have measured the mean divergence between the measured and displayed CTDIvol values were 5.2, 8.4, and -5.7 for selected head, chest and abdomen procedures for protocols as mentioned above, respectively. Thus, this investigation revealed an observable change in CT practices, with a much wider range of studies being performed currently in South India. This reflects the improved capacity of CT scanners to scan longer scan lengths and at finer resolutions as permitted by helical and multislice technology. Also, some of the CT scanners have used smaller slice thickness for routine CT procedures to achieve better resolution and image quality. It leads to an increase in the patient radiation dose as well as the measured CTDIv, so it is suggested that such CT scanners should select appropriate slice thickness and scanning parameters in order to reduce the patient dose. If these routine scan parameters for head, chest and abdomen procedures are optimized than the dose indices would be optimal and lead to the lowering of the CT doses. In South Indian region all the CT machines were routinely tested for QA once in a year as per AERB requirements.

Keywords: CT dose index, weighted CTDI, volumetric CTDI, radiation dose

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1677 Impact of a Biopesticide Formulated an Entomopathogenic Fungus Metarhizium Anisopliae et Abstracts of Two Different Plants Sage (Salvia officinalis) and American Paper (Schinus molle) on Aphis Fabae (Homoptera - Aphididae)

Authors: Hicham Abidallah

Abstract:

In this work we realized a formulation of an entomopathogenic fungus Metarhizium anisopliae with a dose of 1,7 x 105 spores/ml, and aqueous abstracts of two different plants sage (Salvia officinalis) and American paper (Schinus molle) with they’re full dose and half dose, on a black bean aphid populations (Aphis fabae) on a bean crop planted in pots at semi-controlled conditions. Five formulations were achieved (Met, Fd, F1/2d, Sd et S1/2d) and tested on six blocks each one contained six pots. This study revealed that four (04) formulations exercised an influence over black bean aphid (Met, Fd, F1/2d, Sd), of which Metarhizium marked the most elevated and aggressive toxicity with an efficiency of 99,24%, however, sage formulation with the half dose (S1/2d ) marked a weak toxicity with an efficiency of 18%. Test of Metarhizium anisopliae on bees didn’t show toxicity, and no mortality has been marked, and no trace of green Muscardine observed.

Keywords: Metarhizium anisopliae, salvia officinalis, Schinus molle, Aphis fabae, efficiency degree

Procedia PDF Downloads 372
1676 A Hybrid Normalized Gradient Correlation Based Thermal Image Registration for Morphoea

Authors: L. I. Izhar, T. Stathaki, K. Howell

Abstract:

Analyzing and interpreting of thermograms have been increasingly employed in the diagnosis and monitoring of diseases thanks to its non-invasive, non-harmful nature and low cost. In this paper, a novel system is proposed to improve diagnosis and monitoring of morphoea skin disorder based on integration with the published lines of Blaschko. In the proposed system, image registration based on global and local registration methods are found inevitable. This paper presents a modified normalized gradient cross-correlation (NGC) method to reduce large geometrical differences between two multimodal images that are represented by smooth gray edge maps is proposed for the global registration approach. This method is improved further by incorporating an iterative-based normalized cross-correlation coefficient (NCC) method. It is found that by replacing the final registration part of the NGC method where translational differences are solved in the spatial Fourier domain with the NCC method performed in the spatial domain, the performance and robustness of the NGC method can be greatly improved. It is shown in this paper that the hybrid NGC method not only outperforms phase correlation (PC) method but also improved misregistration due to translation, suffered by the modified NGC method alone for thermograms with ill-defined jawline. This also demonstrates that by using the gradients of the gray edge maps and a hybrid technique, the performance of the PC based image registration method can be greatly improved.

Keywords: Blaschko’s lines, image registration, morphoea, thermal imaging

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1675 Study of Effects of Hydro-Alcoholic Extract of Asparagus Root (Asparagus officinalis) Ontestes Spermyogenesis Index of Laboratory Mouse

Authors: Hamid Karimi, Naegar Mahdavi, Hossein Tayefi Nasrabadi

Abstract:

Spermatozoids production rate and its quality are more important factors in the diagnosis of infertility. Also, spematozids activity have a more important role in fertilization. Some medicinal plants as Asparagus(Asparagus officinalis) has many antioxidant component. Therefore, They can affect testes tissue to production more and high-quality spermatozoids. In this survey, Asparagus root extract is studied on spermatogenesis index in the laboratory mouse testes. Hydro-alcoholic extract of asparagus root is prepared and examined on four group of the mature male mouse. Blank group without extract, group 1,100ml/kg dose, group 2, 200 ml/kg dose and group 3, 300ml/kg dose. Then, mice are euthanized, and testes are removed. Testes are weighted, and paraffinized blocks are prepared. TDI(Tubular Differentiation Index) and SPI(Spermiation Index) are studied on histological sections by light microscope. This study results were showed that TDI and SPI in treatments groups with 200 and 300 ml/kg dose had significant enhancement (P<0.05). Consequently, Extract of Asparagus root can enhance spermatozoid production and, therefore, cause improve fertility in male laboratory mice.

Keywords: histology, spermatozoid, ASP [aragus, testes

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1674 Status of Radiation Protection at Radiation Oncology, BPKM Cancer Hospital, Nepal

Authors: Surendra B. Chand, P. P. Chaurasia, M. P. Adhikari, R. N. Yadav

Abstract:

Objective: The objective of this work was to evaluate all the safety procedures toward the radiation protection for workers in the radiation oncology department. Materials and Methods: The annual thermoluminescent dosimeters (TLDs) reports for five years of the staffs were evaluated, radiation surveys were done in the control consoles, radiotherapy machines room and waiting areas of all machines using Aloka survey meter. Results: The five years TLD reports shows that the whole body dose of the individual staffs is found within the annual dose limit except the accidental exposures. Radiation exposures in the working areas are also safe limits. Conclusion: The radiation safety practices for radiation protection are satisfactory and the radiation workers of the departments are found working within the safe limit.

Keywords: radiation protection, safety, ICRP, dose limits, TLD, radiation devices

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1673 Comparison of Titanium and Aluminum Functions as Spoilers for Dose Uniformity Achievement in Abutting Oblique Electron Fields: A Monte Carlo Simulation Study

Authors: Faranak Felfeliyan, Parvaneh Shokrani, Maryam Atarod

Abstract:

Introduction Using electron beam is widespread in radiotherapy. The main criteria in radiation therapy is to irradiate the tumor volume with maximum prescribed dose and minimum dose to vital organs around it. Using abutting fields is common in radiotherapy. The main problem in using abutting fields is dose inhomogeneity in the junction region. Electron beam divergence and lateral scattering may lead to hot and cold spots in the junction region. One solution for this problem is using of a spoiler to broaden the penumbra and uniform dose in the junction region. The goal of this research was to compare titanium and aluminum effects as a spoiler for dose uniformity achievement in the junction region of oblique electron fields with Monte Carlo simulation. Dose uniformity in the junction region depends on density, scattering power, thickness of the spoiler and the angle between two fields. Materials and Methods In this study, Monte Carlo model of Siemens Primus linear accelerator was simulated for a 5 MeV nominal energy electron beam using manufacture provided specifications. BEAMnrc and EGSnrc user code were used to simulate the treatment head in electron mode (simulation of beam model). The resulting phase space file was used as a source for dose calculations for 10×10 cm2 field size at SSD=100 cm in a 30×30×45 cm3 water phantom using DOSXYZnrc user code (dose calculations). An automatic MP3-M water phantom tank, MEPHYSTO mc2 software platform and a Semi-Flex Chamber-31010 with sensitive vol­ume of 0.125 cm3 (PTW, Freiburg, Germany) were used for dose distribution measurements. Moreover, the electron field size was 10×10 cm2 and SSD=100 cm. Validation of devel­oped beam model was done by comparing the measured and calculated depth and lateral dose distributions (verification of electron beam model). Simulation of spoilers (using SLAB compo­nent module) placed at the end of the electron applicator, was done using previously vali­dated phase space file for a 5 MeV nominal energy and 10×10 cm2 field size (simulation of spoiler). An in-house routine was developed in order to calculate the combined isodose curves re­sulting from the two simulated abutting fields (calculation of dose distribution in abutting electron fields). Results Verification of the developed 5.9 MeV elec­tron beam model was done by comparing the calculated and measured dose distributions. The maximum percentage difference between calculated and measured PDD was 1%, except for the build-up region in which the difference was 2%. The difference between calculated and measured profile was 2% at the edges of the field and less than 1% in other regions. The effect of PMMA, aluminum, titanium and chromium in dose uniformity achievement in abutting normal electron fields with equivalent thicknesses to 5mm PMMA was evaluated. Comparing R90 and uniformity index of different materials, aluminum was chosen as the optimum spoiler. Titanium has the maximum surface dose. Thus, aluminum and titanium had been chosen to use for dose uniformity achievement in oblique electron fields. Using the optimum beam spoiler, junction dose decreased from 160% to 110% for 15 degrees, from 180% to 120% for 30 degrees, from 160% to 120% for 45 degrees and from 180% to 100% for 60 degrees oblique abutting fields. Using Titanium spoiler, junction dose decreased from 160% to 120% for 15 degrees, 180% to 120% for 30 degrees, 160% to 120% for 45 degrees and 180% to 110% for 60 degrees. In addition, penumbra width for 15 degrees, without spoiler in the surface was 10 mm and was increased to 15.5 mm with titanium spoiler. For 30 degrees, from 9 mm to 15 mm, for 45 degrees from 4 mm to 6 mm and for 60 degrees, from 5 mm to 8 mm. Conclusion Using spoilers, penumbra width at the surface increased, size and depth of hot spots was decreased and dose homogeneity improved at the junc­tion of abutting electron fields. Dose at the junction region of abutting oblique fields was improved significantly by using spoiler. Maximum dose at the junction region for 15⁰, 30⁰, 45⁰ and 60⁰ was decreased about 40%, 60%, 40% and 70% respectively for Titanium and about 50%, 60%, 40% and 80% for Aluminum. Considering significantly decrease in maximum dose using titanium spoiler, unfortunately, dose distribution in the junction region was not decreased less than 110%.

Keywords: abutting fields, electron beam, radiation therapy, spoilers

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1672 Robustness of the Deep Chroma Extractor and Locally-Normalized Quarter Tone Filters in Automatic Chord Estimation under Reverberant Conditions

Authors: Luis Alvarado, Victor Poblete, Isaac Gonzalez, Yetzabeth Gonzalez

Abstract:

In MIREX 2016 (http://www.music-ir.org/mirex), the deep neural network (DNN)-Deep Chroma Extractor, proposed by Korzeniowski and Wiedmer, reached the highest score in an audio chord recognition task. In the present paper, this tool is assessed under acoustic reverberant environments and distinct source-microphone distances. The evaluation dataset comprises The Beatles and Queen datasets. These datasets are sequentially re-recorded with a single microphone in a real reverberant chamber at four reverberation times (0 -anechoic-, 1, 2, and 3 s, approximately), as well as four source-microphone distances (32, 64, 128, and 256 cm). It is expected that the performance of the trained DNN will dramatically decrease under these acoustic conditions with signals degraded by room reverberation and distance to the source. Recently, the effect of the bio-inspired Locally-Normalized Cepstral Coefficients (LNCC), has been assessed in a text independent speaker verification task using speech signals degraded by additive noise at different signal-to-noise ratios with variations of recording distance, and it has also been assessed under reverberant conditions with variations of recording distance. LNCC showed a performance so high as the state-of-the-art Mel Frequency Cepstral Coefficient filters. Based on these results, this paper proposes a variation of locally-normalized triangular filters called Locally-Normalized Quarter Tone (LNQT) filters. By using the LNQT spectrogram, robustness improvements of the trained Deep Chroma Extractor are expected, compared with classical triangular filters, and thus compensating the music signal degradation improving the accuracy of the chord recognition system.

Keywords: chord recognition, deep neural networks, feature extraction, music information retrieval

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1671 Random Variation of Treated Volumes in Fractionated 2D Image Based HDR Brachytherapy for Cervical Cancer

Authors: R. Tudugala, B. M. A. I. Balasooriya, W. M. Ediri Arachchi, R. W. M. W. K. Rathnayake, T. D. Premaratna

Abstract:

Brachytherapy involves placing a source of radiation near the cancer site which gives promising prognosis for cervical cancer treatments. The purpose of this study was to evaluate the effect of random variation of treated volumes in between fractions in the 2D image based fractionated high dose rate brachytherapy for cervical cancer at National Cancer Institute Maharagama, Sri Lanka. Dose plans were analyzed for 150 cervical cancer patients with orthogonal radiographs (2D) based brachytherapy. ICRU treated volumes was modeled by translating the applicators with the help of “Multisource HDR plus software”. The difference of treated volumes with respect to the applicator geometry was analyzed by using SPSS 18 software; to derived patient population based estimates of delivered treated volumes relative to ideally treated volumes. Packing was evaluated according to bladder dose, rectum dose and geometry of the dose distribution by three consultant radiation oncologist. The difference of treated volumes depends on types of the applicators, which was used in fractionated brachytherapy. The means of the “Difference of Treated Volume” (DTV) for “Evenly activated tandem (ET)” length” group was ((X_1)) -0.48 cm3 and ((X_2)) 11.85 cm3 for “Unevenly activated tandem length (UET) group. The range of the DTV for ET group was 35.80 cm3 whereas UET group 104.80 cm3. One sample T test was performed to compare the DTV with “Ideal treatment volume difference (0.00cm3)”. It is evident that P value was 0.732 for ET group and for UET it was 0.00 moreover independent two sample T test was performed to compare ET and UET groups and calculated P value was 0.005. Packing was evaluated under three categories 59.38% used “Convenient Packing Technique”, 33.33% used “Fairly Packing Technique” and 7.29% used “Not Convenient Packing” in their fractionated brachytherapy treatments. Random variation of treated volume in ET group is much lower than UET group and there is a significant difference (p<0.05) in between ET and UET groups which affects the dose distribution of the treatment. Furthermore, it can be concluded nearly 92.71% patient’s packing were used acceptable packing technique at NCIM, Sri Lanka.

Keywords: brachytherapy, cervical cancer, high dose rate, tandem, treated volumes

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1670 Annual Effective Dose Associated with Radon in Groundwater Samples from Mining Communities Within the Ife-Ilesha Schist Belt, Southwestern Nigeria.

Authors: Paulinah Oyindamola Fasanmi, Matthew Omoniyi Isinkaye

Abstract:

In this study, the activity concentration of ²²²Rn in groundwater samples collected from gold and kaolin mining communities within the Ife-Ilesha schist belt, southwestern Nigeria, with their corresponding annual effective doses have been determined using the Durridge RAD-7, radon-in-water detector. The mean concentration of ²²²Rn in all the groundwater samples was 13.83 Bql-¹. In borehole water, ²²²Rn had a mean value of 20.68 Bql-¹, while it had a mean value of 11.67 Bql-¹ in well water samples. The mean activity concentration of radon obtained from the gold mining communities ranged from 1.6 Bql-¹ from Igun town to 4.8 Bql-¹ from Ilesha town. A higher mean value of 41.8 Bql-¹ was, however, obtained from Ijero, which is the kaolin mining community. The mean annual effective dose due to ingestion and inhalation of radon from groundwater samples was obtained to be 35.35 μSvyr-¹ and 34.86 nSvyr-¹, respectively. The mean annual ingestion dose estimated for well water samples was 29.90 μSvyr-¹, while 52.85 μSvyr-¹ was obtained for borehole water samples. On the other hand, the mean annual inhalation dose for well water was 29.49 nSvyr-¹, while for borehole water, 52.13 nSvyr-¹ was obtained. The mean annual effective dose due to ingestion of radon in groundwater from the gold mining communities ranged from 4.10 μSvyr-¹ from Igun to 13.1 μSvyr-¹ from Ilesha, while a mean value of 106.7 μSvyr-¹ was obtained from Ijero kaolin mining community. For inhalation, the mean value varied from 4.0 nSvyr-¹ from Igun to 12.9 nSvyr-¹ from Ilesha, while 105.2 nSvyr-¹ was obtained from the kaolin mining community. The mean annual effective dose due to ingestion and inhalation is lower than the reference level of 100 μSvyr-¹ recommended by World Health Organization except for values obtained from Ijero kaolin mining community, which exceeded the reference levels. It has been concluded that as far as radon-related health risks are concerned, groundwater from gold mining communities is generally safe, while groundwater from kaolin mining communities needs mitigation and monitoring. It has been discovered that Kaolin mining impacts groundwater with ²²²Rn than gold mining. Also, the radon level in borehole water exceeds its level in well water.

Keywords: 222Rn, Groundwater, Radioactivity, Annual Effective Dose, Mining.

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1669 Effect of Gamma Irradiation on Structural and Optical Properties of ZnO/Mesoporous Silica Nanocomposite

Authors: K. Sowri Babu, P. Srinath, N. Rajeswara Rao, K. Venugopal Reddy

Abstract:

The effect of gamma ray irradiation on morphology and optical properties of ZnO/Mesoporous silica (MPS) nanocomposite was studied. The ZnO/MPS nanocomposite was irradiated with gamma rays of doses 30, 60, and 90 kGy and dose-rate of irradiation was 0.15 kGy/hour. Irradiated samples are characterized with FE-SEM, FT-IR, UV-vis, and Photoluminescence (PL) spectrometers. SEM pictures showed that morphology changed from spherical to flake like morphology. UV-vis analysis showed that the band gap increased with increase of gamma ray irradiation dose. This enhancement of the band gap is assigned to the depletion of oxygen vacancies with irradiation. The intensity of PL peak decreased gradually with increase of gamma ray irradiation dose. The decrease in PL intensity is attributed to the decrease of oxygen vacancies at the interface due to poor interface and improper passivation between ZnO/MPS.

Keywords: ZnO nanoparticles, nanocomposites, mesoporous silica, photoluminescence

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