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John M Manners - One of the best experts on this subject based on the ideXlab platform.
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homologues of the maize rust resistance gene rp1 d are genetically associated with a major rust resistance qtl in sorghum
Theoretical and Applied Genetics, 2004Co-Authors: C L Mcintyre, S Hermann, Rosanne E Casu, D Knight, Stevens M. Brumbley, S B Williams, Jan Drenth, I D Godwin, G R Smith, John M MannersAbstract:As part of a comparative mapping study between sugarcane and sorghum, a sugarcane cDNA clone with homology to the maize Rp1-D rust resistance gene was mapped in sorghum. The cDNA probe hybridised to multiple loci, including one on sorghum linkage group (LG) E in a region where a major rust resistance QTL had been previously mapped. Partial sorghum Rp1-D homologues were isolated from genomic DNA of rust-resistant and -susceptible Progeny selected from a sorghum mapping population. Sequencing of the Rp1-D homologues revealed five discrete sequence classes: three from resistant Progeny and two from susceptible Progeny. PCR primers specific to each sequence class were used to amplify products from the Progeny and confirmed that the five sequence classes mapped to the same locus on LG E. Cluster analysis of these sorghum sequences and available sugarcane, maize and sorghum Rp1-D homologue sequences showed that the maize Rp1-D sequence and the partial sugarcane Rp1-D homologue were clustered with one of the sorghum resistant Progeny sequence classes, while previously published sorghum Rp1-D homologue sequences clustered with the susceptible Progeny sequence classes. Full-length sequence information was obtained for one member of a resistant Progeny sequence class (Rp1-SO) and compared with the maize Rp1-D sequence and a previously identified sorghum Rp1 homologue (Rph1-2). There was considerable similarity between the two sorghum sequences and less similarity between the sorghum and maize sequences. These results suggest a conservation of function and gene sequence homology at the Rp1 loci of maize and sorghum and provide a basis for convenient PCR-based screening tools for putative rust resistance alleles in sorghum.
C L Mcintyre - One of the best experts on this subject based on the ideXlab platform.
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homologues of the maize rust resistance gene rp1 d are genetically associated with a major rust resistance qtl in sorghum
Theoretical and Applied Genetics, 2004Co-Authors: C L Mcintyre, S Hermann, Rosanne E Casu, D Knight, Stevens M. Brumbley, S B Williams, Jan Drenth, I D Godwin, G R Smith, John M MannersAbstract:As part of a comparative mapping study between sugarcane and sorghum, a sugarcane cDNA clone with homology to the maize Rp1-D rust resistance gene was mapped in sorghum. The cDNA probe hybridised to multiple loci, including one on sorghum linkage group (LG) E in a region where a major rust resistance QTL had been previously mapped. Partial sorghum Rp1-D homologues were isolated from genomic DNA of rust-resistant and -susceptible Progeny selected from a sorghum mapping population. Sequencing of the Rp1-D homologues revealed five discrete sequence classes: three from resistant Progeny and two from susceptible Progeny. PCR primers specific to each sequence class were used to amplify products from the Progeny and confirmed that the five sequence classes mapped to the same locus on LG E. Cluster analysis of these sorghum sequences and available sugarcane, maize and sorghum Rp1-D homologue sequences showed that the maize Rp1-D sequence and the partial sugarcane Rp1-D homologue were clustered with one of the sorghum resistant Progeny sequence classes, while previously published sorghum Rp1-D homologue sequences clustered with the susceptible Progeny sequence classes. Full-length sequence information was obtained for one member of a resistant Progeny sequence class (Rp1-SO) and compared with the maize Rp1-D sequence and a previously identified sorghum Rp1 homologue (Rph1-2). There was considerable similarity between the two sorghum sequences and less similarity between the sorghum and maize sequences. These results suggest a conservation of function and gene sequence homology at the Rp1 loci of maize and sorghum and provide a basis for convenient PCR-based screening tools for putative rust resistance alleles in sorghum.
Rosaline Mishra - One of the best experts on this subject based on the ideXlab platform.
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Assessment of Progeny concentrations of 222Rn/220Rn and their related doses using deposition-based direct Progeny sensors.
Environmental Science and Pollution Research, 2018Co-Authors: Sumit Sharma, Rohit Mehra, Manpreet Kaur, Ajay Kumar, Rosaline MishraAbstract:Indoor radon and thoron concentrations in the domestic environment result in natural radiation exposure to the public due to the inhalation of their short-lived decay products. Keeping this in view, the annual effective dose and other radiation risks due to radon/thoron progenies have been calculated. In this study, newly developed time deposition-based Progeny sensors (DTPS/DRPS) were used for long-term passive determination of Progeny concentrations in the environment of Jammu and Kashmir, Himalayas, India. The total equilibrium equivalent radon (EECRA + U) and thoron (EECTA + U) concentrations (“A” and “U” referring to attached and unattached fractions) were found to vary from 5 to 38 Bq m−3 with an average value of 18 Bq m−3 and from 0.48 to 5.49 Bq m−3 with an average value of 1.69 Bq m−3, respectively. The aerosol concentration, equilibrium factors, and unattached fractions for radon and thoron Progeny have been estimated in normal living conditions and their dependence on each others have also been studied. The annual equilibrium factor for radon and thoron Progeny has been determined from the calculated data. The estimated annual effective dose due to radon Progeny (0.34 to 2.42 mSv y−1) and thoron Progeny (0.13 to 1.54 mSv y−1) is found to be below the world’s recommended level. Based on measurements of mean values of the unattached fraction, dose conversion factors (DCFs) in units of mSv per working level month (WLM) has been calculated and the average calculated values of DCFs are 24, 10, and 13 mSv WLM−1. The variability of equilibrium factor and radon/thoron Progeny with different seasons, ventilation conditions, and types of houses were also analyzed.
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Assessment of attached and unattached Progeny concentrations of 222 Rn/ 220 Rn and their contribution to dose using deposition-based Progeny sensors
Environmental Earth Sciences, 2017Co-Authors: Manpreet Kaur, Rohit Mehra, Ajay Kumar, Rosaline MishraAbstract:The exposure of radiation from natural sources to population has become an important issue in terms of radiological protection. Mostly natural radiation comes from radon (222Rn), thoron (220Rn) and their solid short-lived daughter products that are the main threat to public health risk. The results presented in this paper are from a survey carried out in 40 villages of Jammu district, Sub-Mountainous region of Jammu and Kashmir, India, to quantify Progeny concentration of radon and thoron using a passive time integrating, deposition-based technique. For estimating the total (attached + unattached) Progeny concentration of radon/thoron, direct radon/thoron Progeny sensors (DRPS/DTPS) have been used and only attached Progeny concentration of radon/thoron has been measured by using wire-mesh capped direct radon/thoron Progeny sensors (WM-DRPS/WM-DTPS). The study has been conducted for a period of 1 year during winter, rainy and summer seasons in all 112 dwellings. The exposure time of the sensors was 4 months. In this survey, the variability of Progeny concentration of radon and thoron based upon variation in building construction materials and seasons-wise has also been discussed and efforts have been made to provide the reason for these variations. The highest level of Progeny concentration of radon/thoron was found in the mud-type dwellings compared with dwellings made of concrete, cement and marble. Indoor and outdoor gamma dose rate (µSvh−1) has also been measured and correlated indoor gamma annual effective dose (µSvy−1) with Progeny annual effective dose (µSvy−1).
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Estimation of attached and unattached Progeny of 222Rn and 220Rn concentration using deposition based Progeny sensors
Radiation Protection Dosimetry, 2015Co-Authors: Rohit Mehra, Pargin Bangotra, Kirandeep Kaur, S. D. Kanse, Rosaline MishraAbstract:: The attached and unattached radon and thoron Progeny concentrations have been calculated using deposition-based Progeny sensors in Mansa, Muktsar, Bathinda and Faridkot districts of Punjab, India. The total (attached + unattached) equilibrium-equivalent (222)Rn concentration (EECRA + U) and total (attached + unattached) equilibrium-equivalent (220)Rn concentration (EECTA + U) were found to vary from 9 to 46 Bqm(-3) and 0.5 to 3.1 Bq m(-3), respectively. The concentrations of attached Progeny nuclides for both (222)Rn and (220)Rn have been found to be greater than the unattached Progeny nuclides in the dwellings of studied area. An attempt has also been made to assess the effective dose for (222)Rn and (220)Rn in the studied area. The radiation dose originated from (222)Rn and (220)Rn Progeny is low and health risk is negligible.
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An integrated approach for the assessment of the thoron Progeny exposures using direct thoron Progeny sensors
Radiation Protection Dosimetry, 2010Co-Authors: Rosaline Mishra, B.k. Sapra, R. Prajith, Y.s. MayyaAbstract:: Assessing the risks due to thoron and its Progeny is of considerable importance in the public domain and in operations related to the thorium fuel cycle. Deposition-based Progeny concentration measurement techniques (direct thoron Progeny sensors, DTPSs) appear to be best suited for radiological risk assessments among both occupational workers and general populations. The DTPSs lodged in wire-mesh and filter paper-integrated sampler and operated in flow mode can be used to measure the unattached and attached fractions. The wire-mesh-capped DTPS system can be used to measure the deposition velocity of the unattached and attached fractions separately. In the present work, the DTPSs in different modes have been described and the experiments for measuring the multiple parameters related to the indoor thoron Progeny are presented.
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Development of an integrated sampler based on direct 222Rn/220Rn Progeny sensors in flow-mode for estimating unattached/attached Progeny concentration
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2009Co-Authors: Rosaline Mishra, B.k. Sapra, Y.s. MayyaAbstract:Abstract A flow-mode integrated sampler consisting of a wire-mesh and filter-paper array along with passive solid state nuclear track detectors has been developed for estimating unattached and attached fraction of 222Rn/220Rn Progeny concentration. The essential element of this sampler is the direct 222Rn/220Rn Progeny sensor (DRPS/DTPS), which is an absorber-mounted-LR115 type nuclear track detector that selectively registers the alpha particles emitted from the Progeny deposited on its surface. During sampling at a specified flow-rate, the unattached Progeny is captured on the wire-mesh; while the attached Progeny gets transmitted and is captured on the filter-paper. The alpha particles emitted by the deposited Progeny atoms are registered on the sensors placed at a specified distance facing the wire-mesh and the filter-paper, respectively. The various steps involved in the development of this flow-mode direct Progeny sampler such as the optimization of the sampling rate and the distance between the sensor and the deposition substrate are discussed. The sensitivity factor of the DTPS-loaded sampler for 220Rn Progeny deposited on the wire-mesh and filter-paper is found to be 23.77 ± 0.64 (track cm−2 h−1) (Bq m−3)−1 and 22.30 ± 0.18 (track cm−2 h−1) (Bq m−3)−1, respectively; while that of DRPS-loaded sampler for 222Rn Progeny deposition, is 3.03 ± 0.14 (track cm−2 h−1) (Bq m−3)−1 and 2.08 ± 0.07 (track cm−2 h−1) (Bq m−3)−1, respectively. The highlight of this flow-mode sampler is its high sensitivity and that it utilizes the passive technique for estimating the unattached and attached Progeny concentration, thus doing away with the alpha counting procedures.
Shinji Tokonami - One of the best experts on this subject based on the ideXlab platform.
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comparative analysis of radon thoron and thoron Progeny concentration measurements
Journal of Radiation Research, 2013Co-Authors: Miroslaw Janik, Shinji Tokonami, C Kranrod, Atsuyuki Sorimachi, Tetsuo Ishikawa, Masahiro Hosoda, J Mclaughlin, Byunguck ChangAbstract:This study examined correlations between radon, thoron and thoron Progeny concentrations based on surveys conducted in several different countries. For this purpose, passive detectors developed or modified by the National Institute of Radiological Sciences (NIRS) were used. Radon and thoron concentrations were measured using passive discriminative radon-thoron detectors. Thoron Progeny measurements were conducted using the NIRS-modified detector, originally developed by Zhuo and Iida. Weak correlations were found between radon and thoron as well as between thoron and thoron Progeny. The statistical evaluation showed that attention should be paid to the thoron equilibrium factor for calculation of thoron Progeny concentrations based on thoron measurements. In addition, this evaluation indicated that radon, thoron and thoron Progeny were independent parameters, so it would be difficult to estimate the concentration of one from those of the others.
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Characteristics of thoron and thoron Progeny in Canadian homes
Radiation and Environmental Biophysics, 2010Co-Authors: Jing Chen, Atsuyuki Sorimachi, Deborah Moir, Shinji TokonamiAbstract:Naturally occurring isotopes of radon in indoor air are identified as the second leading cause of lung cancer after tobacco smoking. Radon-222 (radon gas) and radon-220 (thoron gas) are the most common isotopes of radon. While the radon equilibrium factor is well established, the equilibrium factor between thoron Progeny and thoron gas is still not well known. Thoron gas and Progeny concentrations were determined in the lowest floors of 138 Canadian homes simultaneously. While thoron gas was only detectable in about 52% of the homes, thoron Progeny concentrations were measured in every home surveyed. Thoron concentrations, thoron Progeny concentrations, and the equilibrium factors varied widely and were log-normally distributed. With a 3 months simultaneous measurement of thoron and thoron Progeny concentrations, the equilibrium factor was determined to be 0.024 with a geometric standard deviation of 2.7.
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Mitigation of the effective dose of radon decay products through the use of an air cleaner in a dwelling in Okinawa, Japan
Applied Radiation and Isotopes, 2009Co-Authors: C Kranrod, Miroslaw Janik, Shinji Tokonami, Atsuyuki Sorimachi, Tetsuo Ishikawa, Reina Shingaki, Masahide Furukawa, Supitcha Chanyotha, Nares ChankowAbstract:Abstract Field measurements were conducted to assess the effects of an air cleaner on radon mitigation in a dwelling with a high radon concentration in Okinawa, Japan. The measurements included indoor radon concentration, individual radon Progeny concentration, equilibrium equivalent concentration of radon (EECRn), unattached fraction, and size distribution of aerosol-attached radon Progeny. These measurements were conducted in a 74 m3 room with/without the use of an air cleaner. The results showed that the mean radon concentration during the measurement was quite high (301 Bq m−3). The operation of air cleaner decreased the radon Progeny activity concentration, EECRn and equilibrium factor by 33%, 57% and 71%, respectively, whereas the unattached fraction increased by 174%. In addition, the activity concentration of attached radon Progeny in the accumulation mode (50–2000 nm) was obviously deceased by 42%, when the air cleaner was operated. According to dosimetric calculations, the operation of air cleaner reduced the effective dose due to radon Progeny by about 50%.
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Measurements of radon, thoron and their Progeny in Gifu prefecture, Japan
Journal of Radioanalytical and Nuclear Chemistry, 2005Co-Authors: Cs. Németh, Shinji Tokonami, Tetsuo Ishikawa, H. Takahashi, W. Zhuo, M. ShimoAbstract:Due to the rocky neighborhood, consisting of mostly granite with high radium content, an elevated radon concentration was found in a territory of Gifu prefecture situated in the middle of Japan. Radon concentrations in water were measured and were found to be considerably high. Since indoor radon and radon Progeny concentrations might be relatively high, their concentrations were also analyzed. Besides the radon and radon Progeny, thoron and thoron Progeny concentrations were also investigated. Dose estimations for radon and thoron in indoor air are discussed.
I D Godwin - One of the best experts on this subject based on the ideXlab platform.
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homologues of the maize rust resistance gene rp1 d are genetically associated with a major rust resistance qtl in sorghum
Theoretical and Applied Genetics, 2004Co-Authors: C L Mcintyre, S Hermann, Rosanne E Casu, D Knight, Stevens M. Brumbley, S B Williams, Jan Drenth, I D Godwin, G R Smith, John M MannersAbstract:As part of a comparative mapping study between sugarcane and sorghum, a sugarcane cDNA clone with homology to the maize Rp1-D rust resistance gene was mapped in sorghum. The cDNA probe hybridised to multiple loci, including one on sorghum linkage group (LG) E in a region where a major rust resistance QTL had been previously mapped. Partial sorghum Rp1-D homologues were isolated from genomic DNA of rust-resistant and -susceptible Progeny selected from a sorghum mapping population. Sequencing of the Rp1-D homologues revealed five discrete sequence classes: three from resistant Progeny and two from susceptible Progeny. PCR primers specific to each sequence class were used to amplify products from the Progeny and confirmed that the five sequence classes mapped to the same locus on LG E. Cluster analysis of these sorghum sequences and available sugarcane, maize and sorghum Rp1-D homologue sequences showed that the maize Rp1-D sequence and the partial sugarcane Rp1-D homologue were clustered with one of the sorghum resistant Progeny sequence classes, while previously published sorghum Rp1-D homologue sequences clustered with the susceptible Progeny sequence classes. Full-length sequence information was obtained for one member of a resistant Progeny sequence class (Rp1-SO) and compared with the maize Rp1-D sequence and a previously identified sorghum Rp1 homologue (Rph1-2). There was considerable similarity between the two sorghum sequences and less similarity between the sorghum and maize sequences. These results suggest a conservation of function and gene sequence homology at the Rp1 loci of maize and sorghum and provide a basis for convenient PCR-based screening tools for putative rust resistance alleles in sorghum.
