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Sample records for progeny concentration variations

  1. Thoron and radon progeny concentration measurements using direct progeny sensors in HLNRAs of Kerala

    International Nuclear Information System (INIS)

    Mishra, R.; Prajith, R.; Gole, A.C.; Kanse, S.D.; Chougaonkar, M.P.; Sapra, B.K.; Mayya, Y.S.; Jayalekshmi, P.; Nair, Raghu Ram K.

    2010-01-01

    Passive Progeny Dosimeters (PPDs) were deployed in 500 houses in 3 villages namely Allapad, Chavara and Neendakara villages of Karunagapally Taluk of Kollam district of Kerala. Each PPD unit is a combination of a DTPS and a DRPS placed side-by-side for time integrated thoron and radon progeny concentration estimation respectively. The PPDs were suspended vertically in the rooms, such that the nearest distance from any wall or surface was at least 30 cm. These are, as of now, being exposed for a period of 3 months, after which they will be retrieved and analysed by chemical etching and track counting. Simultaneously, external gamma radiation measurements have also been made using a survey meter; these showed a variation from 13 to 118 μR/h in indoors and 21 to 213 μR/h in the outdoor environments. Spot measurements of thoron progeny concentrations were also made in 7 selected houses using the conventional grab filter-paper sampling technique at a flow-rate of 21 min -1 for 30 minutes, followed by alpha counting. The average thoron progeny concentration was found to be 2.0 ± 0.7 Bq m -3 . In the outdoor environment, filter-paper sampling was carried out for 2 hours at 21 min -1 and the thoron progeny concentration was measured as 2.96 Bq m -3 . To corroborate these measurements, a flow mode integrated sampler which uses the DTPS and DRPS elements was used

  2. Variation of indoor radon progeny concentration and its role in dose assessment

    International Nuclear Information System (INIS)

    Singh, Manmohan; Singh, Kulwant; Singh, Surinder; Papp, Z.

    2008-01-01

    Instantaneous measurements of equilibrium equivalent concentration of radon (EEC Rn ) were taken over a period of 1 year in 2004 in a typical house at Amritsar city, located in the northwest part of India. A method based on absolute beta counting subsequent to grab aerosol sampling was used. During that year, EEC Rn varied between 1.56 Bq m -3 and 22.77 Bq m -3 with average value of 8.76 Bq m -3 . EEC Rn decreased with the transition from winter to summer and vice versa, having a negative correlation with outdoor temperature. The use of mechanical ventilation, under normal living conditions during summer, caused an extra decrease in the concentrations. The variations with temperature and mechanical ventilation are discussed. Some major issues related to the uncertainties in dose calculations caused by the lack of knowledge of equilibrium factor and ignoring the effect of life style on the radon and its progeny concentrations are discussed

  3. Concentration ratio of radon progeny in air

    International Nuclear Information System (INIS)

    Kobayashi, Tsuneo

    2000-01-01

    Investigations have been made on the concentration ratio of radon progeny in air. Data have been acquired intermittently since 1988 using alpha spectroscopic method around the author's office that is located in the northeastern part of Japan. Clarifying the behavior of radon progeny is an issue of wide importance to radiation protection, predicting earthquakes, etc. Let Rabc=ECRn(RaA)/{ECRn(RaB) + ECRn(RaC)}; the concentration ratio, Rabc, is relevant to the stability of the air. Statistical and time series analyses indicated several interesting results. To examine the log-normal distribution, Lilliefors test was made for logarithm of outdoor data every one year. Rabc passed the test 6 times for 9 years, while Radon progeny passed 8 times. Outdoor data indicated that the value of Rabc was lower in the morning, in other world, the air was more stable in the morning than in the afternoon. To see the seasonal variation, one-way layout analysis was made for four groups of data, i.e., spring (March to May), summer (June to August), autumn (September to November), and winter (December to February). Rabc indicated significantly higher level in spring and winter, in other word, air was stable in summer and autumn. Time series analysis was made for various variables; power spectra were estimated with autoregressive model that is equivalent to maximum entropy method. Power spectrum for Rabc was most similar to that of wind speed. One-year period, that is always remarkable for radon progeny, was not significant for Rabc. Three- to nine-day periods were often seen for Rabc, radon progeny, wind speed, and atmospheric pressure. These several-day periods are probably attributed to the passage of air masses. Twenty-day to thirty-day peak may be attributed to meteorological phenomena corresponding to the rotation period of the sun. Temperature indicated no significant periodicity except overwhelming one-year period. Wind speed is well known to affect the radon progeny concentration

  4. Temporal and vertical variations radon and its progeny related to atmospheric electrical conductivity

    International Nuclear Information System (INIS)

    Pruthvi Rani, K.S.; Chandrashekara, M.S.; Paramesh, L.

    2015-01-01

    Atmospheric radon, its progeny, electrical conductivity and meteorological parameters such as wind, temperature, humidity, pressure and rainfall were continuously monitored during 2012 to 2014 at one location in Mysuru city. The annual mean atmospheric radon concentration at the study location was found to be 16.4 Bqm -3 . The diurnal cycle of radon and its progeny show a peak in the early morning hours followed by a drastic decrease after sunrise and rising to a second peak in the afternoon. It was found that the stability of the atmosphere and ambient temperature played a major role in the diurnal variations. Higher concentrations of radon and its progeny were observed in winter and lower values in summer. This may due to the variations in origin of air mass and meteorological parameters. Wind direction analyses reveal that in sectors with air which has spent a longer period over the granitic region and low wind speeds will lead to higher concentrations of radon. Atmospheric electrical conductivity near the ground is mainly due to the ionization from radon and its progeny. The diurnal variations of conductivity and ionization rate due to radon and its individual progeny were of similar trend. In addition its significant dependence on meteorological parameters is confirmed. The vertical variations of atmospheric electrical conductivity were studied at different heights up to 250 m from the ground level. Higher values were observed close to the ground surface, there was a rapid reduction up to about 10 m and beyond that the conductivity gradually decreases. The diurnal conductivity cycle is studied at 10 m and 100 m showed the expected similar trend at both the heights but early morning maxima were considerably different, this confirms the accumulation of radon gas close to the ground surface during night time leading to increase of conductivity values. (author)

  5. The study of thoron and radon progeny concentrations in dwellings in Japan

    International Nuclear Information System (INIS)

    Guo, Q.; Shimo, M.; Ikebe, Y.

    1992-01-01

    Ths paper aims to make a comparison of different concentrations of thoron ( 220 Rn) progeny and radon ( 222 Rn) progeny in different kinds of dwellings. The potential alpha energy concentrations and the effective dose equivalent caused by thoron and radon progeny, respectively, have also been estimated. The measurements were carried out in 23 dwellings. The results indicate that thoron progeny concentrations indoors might be strongly affected by the type of building material used. Traditional Japanese buildings made with mud may have high thoron progeny concentrations of about 3.52 Bq.m -3 and a concentration ratio of thoron progeny to radon progeny of about 0.5, whereas in concrete dwellings thoron progeny concentrations are about 0.72 Bq.m -3 and the concentration ratio of thoron progeny to radon progeny is about 0.1. The annual effective dose equivalent of thoron progeny is 1.23 mSv in mud dwellings and 0.25 mSv in concrete dwellings. (author)

  6. Diurnal Variations of Equilibrium Factor and Unattached fraction of Radon Progeny in Some Houses and Laboratories

    International Nuclear Information System (INIS)

    Lee, Seung Chan; Kang, Hee Dong; Kim, Chang Kyu; Lee, Dong Myung

    2001-01-01

    The variation characteristics of radon concentration, equilibrium equivalent concentration and equilibrium factor in some house and laboratory buildings have been studied. The variation of equilibrium factor and the unattached fraction of radon progeny with ventilation condition have been also estimated. The averages of radon concentration, equilibrium equivalent concentration and equilibrium factor were 30 Bq m -3 , 19.6 Bq m -3 and 0.65 in seven houses, while 55.0 Bq m -3 , 31.9 Bq m -3 and 0.58 in three laboratory buildings, respectively. The diurnal variation of radon concentration, equilibrium equivalent concentration and equilibrium factor in indoor showed a typical pattern that the radon concentration, equilibrium equivalent concentration and equilibrium factor increased at dawn and morning, while decreased at midday and evening. While the equilibrium factor rate deceased in the indoor environment which was well ventilated, the unattached fraction of radon progeny increased. The equilibrium factor was in proportion to air pressure and humidity of indoor, whereas in inverse proportion to temperature

  7. Control of indoor radon and radon progeny concentrations

    International Nuclear Information System (INIS)

    Sextro, R.G.

    1985-05-01

    There are three general categories of techniques for the control of radon and radon progeny concentrations in indoor air - restriction of radon entry, reduction of indoor radon concentrations by ventilation or air cleaning, and removal of airborne radon progeny. The predominant radon entry process in most residences appears to be pressure driven flow of soil gas through cracks or other openings in the basement, slab, or subfloor. Sealing these openings or ventilation of the subslab or subfloor space are methods of reducing radon entry rates. Indoor radon concentrations may be reduced by increased ventilation. The use of charcoal filters for removal of radon gas in the indoor air by adsorption has also been proposed. Concentrations of radon progeny, which are responsible for most of the health risks associated with radon exposures, can be controlled by use of electrostatic or mechanical filtration. Air circulation can also reduce radon progeny concentrations in certain cases. This paper reviews the application and limitations of each of these control measures and discusses recent experimental results

  8. Integrating measurements of indoor thoron and its progeny concentrations

    International Nuclear Information System (INIS)

    Zhuo, W.H.; Iida, T.; Hashiguchi, Y.

    2000-01-01

    In recent years, indoor surveys in Europe and Asia revealed that the dose contribution from thoron and its progeny can equal or even exceed that of radon and its progeny. For measuring thoron and its progeny, several methods had been reported. However, convenient, low-cost and time-integrating measuring methods which are suitable for large-scale surveys are still unavailable. To solve this problem, three integrating measuring methods with allyl diglycol carbonate plastic (CR-39) as detectors have recently been. The results indicated that they are suitable for estimating the indoor thoron and its progeny concentrations when the public exposure to thoron and its progeny is taken into account. Cup monitor - Former types of passive integrating 222 Rn and 220 Rn cup monitors had been reported. Recently, in order to improve the sensitivity of thoron detection, the air exchange rate between the inner and outer cup was enhanced, and the radius of the hemisphere was reduced to 37.5 mm. Furthermore, the procedure of detector exchange was made to be more convenient. Equilibrium-equivalent 222 Rn and 220 Rn concentrations monitor (EEC monitor) - The measuring system is composed of a monitor head and a diaphragm pump. The total weight of the system is less than 1.5 kg, which makes it portable. The construction of the monitor head and the measuring principle were also reported by the authors. Thoron progeny deposition rate monitor - The monitor is simply constituted a piece of CR-39 covered with thin sheets of absorbers. The thickness of the absorbers are adjusted to let only the α particles emitted from 212 Pb impinge on the detector. The concentrations of thoron progeny are estimated from the deposition rates, assuming that the deposition velocities of thoron progeny are constant in general dwellings. The improved cup monitor has higher sensitivity than former monitors, with a calibration factor of 1.59x10 -3 tracks·cm -2 (Bq·m -3 ·h) -1 for thoron. The accuracy of the ECC

  9. Characteristics of radon and its progeny concentrations in air-conditioned office buildings in Tokyo

    International Nuclear Information System (INIS)

    Tokonami, S.; Furukawa, M.; Shicchi, Y.; Sanada, T.; Yamada, Y.

    2003-01-01

    A series of measurements were carried out to understand the characteristics of radon and its progeny in air-conditioned office buildings. Long-term measurements of radon were made with etched track detectors. Continuous measurements of radon and its progeny concentrations were also conducted in some buildings to study their temporal variations. The results show that radon and its progeny concentrations routinely varied along with working activities. They are generally low while people are working, due to air conditioning, whereas they rise steadily after the air conditioning stops. When considering action levels not only in homes but also workplaces, attention should be paid to annual doses from the viewpoint of radiation protection. The annual dose is generally estimated with a long-term measurement of radon concentration using a passive device such as an etched track detector. Since its reading corresponds to a long-term average concentration regardless of working hours, the annual dose will be overestimated. When comparing a real dose after considering the working hours, they differ by a factor of more than 2. (author)

  10. Diurnal variations of indoor radon progeny for Bangalore metropolitan, India

    International Nuclear Information System (INIS)

    Nagesh, V.; Sathish, L.A.; Nagaraja, K.; Sundareshan, S.

    2010-01-01

    Radon progenies are identified as major causes of the lung cancer if the activity is above its normal. It has not been clear whether radon poses a similar risk of causing lung cancer in humans exposed at generally lower levels found in homes, but a number of indoor radon survey have been carried out in recent years around the world. In view of this an attempt has been made for the measurement of diurnal variation of indoor radon levels for the environment of Bangalore metropolitan, India. The Radon progeny concentrations in terms of working level were measured using Kusnetz's method. The patterns of daily and annual changes in indoor Radon concentration have been observed in a general way for many years. However, understanding of the physical basis for these changes had to await the development of continuous monitors and a more complete knowledge of transport processes in the atmosphere. Over a continent, heating of the ground surface by the Sun during the day and cooling by radiation during the night causes a marked diurnal change in temperature near the surface. As a result cool air near the ground will accumulate radon isotopes from surface flux during the night; while during the day the warm air will be transported upward carrying radon with it. Many buildings show diurnal radon variations. Concentrations are relatively higher during night than daytime. This is influenced by the outdoor-indoor temperature contrast. This effect can be enhanced in buildings with strong diurnal use patterns. Buildings that have high average radon concentrations, but are only occupied for part of the day, may need to be measured during occupied periods to determine if there is significant diurnal radon variation. The results are discussed in detail. (author)

  11. Evaluation of indoor aerosol control devices and their effects on radon progeny concentrations

    International Nuclear Information System (INIS)

    Sextro, R.G.; Offermann, F.J.; Nazaroff, W.W.; Nero, A.V.; Revzan, K.L.; Yater, J.

    1984-02-01

    Eleven portable air cleaning devices have been evaluated for control of indoor concentrations of respirable particles, and their concomitant effects on radon progeny concentrations have been investigated. Of the devices we examined the electrostatic precipitators and extended surface filters had significant particle removal rates, while the particle removal rates for several small panel-filters, an ion-generator, and a pair of mixing fans were found to be negligible. The evaluation of radon progeny control produced similar results; the air cleaners which were effective in removing particles were also effective in reducing radon progeny concentrations. Furthermore, at the low particle concentrations, plateout of the unattached radon progeny was found to be a significant removal mechanism. The overall removal rates due to deposition of attached and unattached progeny have been estimated from these data, and the equilibrium factors for total and unattached progeny concentrations have been calculated as a function of particle concentration. 7 references, 2 figures

  12. Evaluation of indoor aerosol control devices and their effects on radon progeny concentrations

    International Nuclear Information System (INIS)

    Sextro, R.G.; Offerman, F.J.; Nazaroff, W.W.; Nero, A.V.; Revzan, K.; Yater, J.

    1984-01-01

    Eleven portable air cleaing devices have been evaluated for control of indoor concentrations of respirable particles, and their concomitant effects on radon progeny concentrations have been investigated. Of the devices we examined the electrostatic precipitators and extended surface filters had significant particle removal rates, while the particle removal rates for several small panel-filters, an ion-generator, and a pair of mixing fans were found to be negligible. The evaluation of radon progeny control produced similar results; the air cleaners which were effective in removing particles were also effective in reducing radon progeny concentrations. Futhermore, at the low particle concentrations, plateout of the unattached radon progeny was found to be a significant removal mechanism. The overall removal rates due to deposition of attached and unattached progeny have been estimated from these data, and the equilibrium factors for total and unattached progeny concentrations have been calculated as a function of particle concentration. (Author)

  13. Evaluation of indoor aerosol control devices and their effects on radon progeny concentrations. Revision

    International Nuclear Information System (INIS)

    Sextro, R.G.; Offermann, F.J.; Nazaroff, W.W.; Nero, A.V.; Revzan, K.L.; Yater, J.

    1984-11-01

    Eleven portable air cleaning devices have been evaluated for control of indoor concentrations of respirable particles, and their concomitant effects on radon progeny concentrations have been investigated. The experiments were conducted in a room-size chamber using cigarette smoke and radon injection from an external source. Of the devices examined the electrostatic precipitators and extended surface filters had significant particle removal rates, while the particle removal rates for several small panel-filters, an ion-generator, and a pair of mixing fans were found to be essentially negligible. The evaluation of radon progeny control produced similar results; the air cleaners which were effective in removing particles were also effective in reducing radon progeny concentrations. At the low particle concentrations, deposition of the unattached radon progeny on room surfaces was found to be a significant removal mechanism. Deposition rates of attached and unattached progeny have been estimated from these data, and were used to calculate the equilibrium factors for total and unattached progeny concentrations as a function of particle concentration. While particle removal reduces total airborne radon progeny concentrations, the relative alpha decay dose to the lungs appears to change very little as the particle concentration decreases due to the greater radiological importance of unattached progeny

  14. Measurements of thoron and radon progeny concentrations in Beijing, China

    International Nuclear Information System (INIS)

    Zhang Lei; Liu Cuihong; Guo Qiuju

    2008-01-01

    It has been reported that thoron levels in China are above the world average and may therefore make a significant contribution to the natural background radiation dose. We therefore conducted a pilot study of concentrations of both thoron and radon progeny during the spring of 2006 in the Beijing area, China. A new type of portable 24 h integrating monitor with a CR-39 detector was used during the survey. Seventy dwellings and eight outdoor sites were measured during the survey. For country houses built of red bricks and slurry, the average equilibrium equivalent concentrations (EEC) of thoron and radon were 1.02 ± 0.48 and 16.41 ± 9.02 Bq m -3 , respectively, whereas for city dwellings built of cement blocks and floor slabs, the results were 0.48 ± 0.47 and 11.50 ± 6.99 Bq m -3 for thoron and radon, respectively. For outdoor air, concentrations of thoron and radon progeny were 0.29 ± 0.28 and 7.05 ± 2.68 Bq m -3 , respectively. Radiation exposures from thoron and radon progeny were also evaluated; the ratio of dose contribution from thoron progeny to that of radon progeny was evaluated to be 28% and 17% in country houses and city dwellings, respectively. (note)

  15. Seasonal and diurnal variations in potential alpha energy concentrations at a location in tropical Australia

    International Nuclear Information System (INIS)

    Quintarelli, F.; Akber, R.

    1998-01-01

    Full text: Atmospheric concentrations of radon progeny activity were measured at two locations in tropical Australia during the time period 1992 - 1994. Meteorological parameters including atmospheric pressure, temperature and humidity were also recorded. The data were analysed for seasonal and diurnal variations, in order to establish correlations and associations amongst radon progeny concentrations and meteorological parameters. The paper describes the findings, including the attachment behaviour of radon progeny to ambient aerosol

  16. Control methods of radon and its progeny concentration in indoor atmosphere

    International Nuclear Information System (INIS)

    Ramachandran, T.V.; Subba Ramu, M.C.

    1990-01-01

    Exposure to radon-222 and its progeny in indoor atmosphere can result in significant inhalation risk to the population particularly to those living in houses with much higher levels of Rn. There are three methods generally used for the control of Rn and its progeny concentration in the indoor environment: (1) restricting the radon entry, (2) reduction of indoor radon concentration by ventilation or by aircleaning and (3) removal of airborne radon progeny by aerosol reduction. Prominent process of radon entry in most of the residence appears to be the pressure driven flow of soil gas through cracks or through other openings in the basements slab or subfloor. Sealing off these openings or ventilation of the slab or subfloor spaces are the methods of reducing the radon entry rate. Indoor radon progeny levels can also be reduced by decreasing the aerosol load in the dwellings. The results of a few experiments carried out to study the reduction in the working level concentration of radon, by decreasing the aerosol load are discussed in this paper. (author). 9 tabs., 8 figs., 37 refs

  17. Control of radon and its progeny concentration in indoor atmosphere

    International Nuclear Information System (INIS)

    Ramachandran, T.V.; Subbaramu, M.C.

    1986-01-01

    Exposure to radon daughter concentration in indoor atmosphere can result in a significant risk to the general public. There are two generally used methods for the control of radon and progeny concentration in the indoor atmosphere, namely restriction of radon entry and reduction of indoor radon and its progeny concentration by ventilation or by air cleaning. Predominant radon entry process in most of the dwellings appears to be by pressure driven flow of soil gas through cracks or other openings in the basement slab or subfloors. Sealing these openings or ventilation of the subslab or subfloor space are the methods for reducing the radon entry rates. Indoor radon concentration can also be reduced by increasing the ventilation and by using charcoal filters for the removal of radon gas in indoor air by absorption. Concentration of radon progeny, which are responsible for most of the health risks associatd with radon exposure can also be controlled by the use of electrostatic or mechanical filters. This study describes briefly the above control strategies used for reducing the inhalation doses to persons in dwellings. (author). 9 refs., 2 tables

  18. Study on calculation models and distribution rules of the radon concentration and its progenies concentration in blind roadway with forced-exhaust ventilation

    International Nuclear Information System (INIS)

    Ye Yongjun; Wang Liheng; Zhou Xinghuo; Li Xiangyang; Zhong Yongming; Wang Shuyun; Ding Dexin

    2014-01-01

    The forced-exhaust ventilation is an important way to control the concentration of radon and its progenies in long-distance blind driving roadway. It is of great significance for guiding the design of ventilation and radiation protection to study distribution characteristics of the concentration of radon and its progenies in the wind of roadway adopting the forced-exhaust ventilation. Therefore, according to the decay relationship of radon and its progenies, a simplified mathematical calculation model was built, which relates to the radon activity concentration and the potential alpha concentration of radon progenies. The paper also analyzed the sources of radon and its progenies in the limited space of the blind roadway. Then, based on the turbulence mass transfer theory of ventilation air flow, the paper established mathematical calculation models of distribution characteristics of the radon activity concentration and the potential alpha concentration of radon progenies in blind roadway with forced-exhaust ventilation, respectively. Finally, the paper applied the calculation models to a special blind roadway, and discussed the influence of the ventilation air inflow and the radon exhalation rate of rock wall on the distribution of radon concentration and the potential alpha concentration of radon progenies in the roadway. Meanwhile, some protective measurements were put forward to reduce the radiation dose of worker caused by radon and its progenies in the blind roadway. (authors)

  19. Effect of ventilation rate on concentrations of indoor radon and its progenies

    International Nuclear Information System (INIS)

    Wang Chunhong; Liu Yanyang; Liu Fudong; Liu Senlin; Chen Ling

    2012-01-01

    To study concentrations of indoor radon and its progenies, ventilation rates and their corresponding concentrations of indoor radon and its progenies were measured using tracer-gas dilution method. Results show that both ventilation rates and concentrations of indoor radon varied insignificantly and radon concentration were higher than the outdoor environment while doors and windows were all closed with air-conditioner on and off respectively; the concentrations declined and close to the outdoor level when doors and windows were all open with ventilators in operation. Accordingly, in modern life, especially in summer, people's preference for air-conditioners but natural ventilation would result in an increase of indoor radon concentration. (authors)

  20. Study on seasonal variation of indoor radon, thoron and their progeny levels in Hassan District of Karnataka, India

    International Nuclear Information System (INIS)

    Srinivasa, E.; Rangswamy, D.R.; Sannappa, J.

    2015-01-01

    Radon, thoron and their progeny concentrations have been measured in different types of buildings at different locations for different seasons in Hassan city using time-integrated passive radon dosimeters containing LR-115 Type II solid state nuclear track detector exposed for four seasons of 3 months each covering a period of one year from October 2012 to September 2013. The radon and thoron activity concentration in summer season in the corresponding dwellings has been found to vary from 7.4 to 45.7 Bq m -3 and 5.4 to 34.9 Bqm -3 with a median of 23.59±11 Bqm -3 and 1447±8 Bq -3 respectively. The radon progeny concentrations varies from 0.4 to 4.1 mWL with an average value of 1.83±1 mWL, while thoron progeny concentrations vary from 0.3 to 3.2 mWL with an average value of 1.12±0.7 mWL respectively. The annual effective dose received due to radon, thoron and its progeny by the inhabitants in the dwellings under study has also been calculated which is found to vary from 0.320±0.4 to 1.860 ±1.1 mSv y -1 with an average value of 0.9576 ± 0.8 mSv y -1 . In general, the level of radon-thoron was observed highest in winter and lowest in summer. A detail analysis of radon and thoron distribution in different houses with seasonal variation is presented in this paper. From this study it is observed that, bathrooms and kitchens have significantly higher radon concentrations as compared to other rooms in the dwellings. (author)

  1. Development of an integrated sampler based on direct 222Rn/220Rn progeny sensors in flow-mode for estimating unattached/attached progeny concentration

    International Nuclear Information System (INIS)

    Mishra, Rosaline; Sapra, B.K.; Mayya, Y.S.

    2009-01-01

    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 222 Rn/ 220 Rn progeny concentration. The essential element of this sampler is the direct 222 Rn/ 220 Rn 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 220 Rn 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 222 Rn 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.

  2. Filtration approach to mitigate indoor Thoron progeny concentration

    International Nuclear Information System (INIS)

    Wang, J.; Meisenberg, O.; Karg, E.; Tschiersch, J.; Chen, Y.

    2010-01-01

    This study investigates filtration of air as potential mitigation method of thoron progeny exposure. The experiments were conducted in a model room (volume 7.1 m 3 ) which was equipped with a pump and an HEPA (high efficiency particulate air) filter. Filtration at a rate of 0.2, 0.4, 0.5 and 0.8 h -1 during 88 h proved an effective practice in reducing the total indoor thoron decay product concentration. The results indicate that 0.4-0.8 h -1 filtration rate had almost the same filtration efficiency in decreasing the total thoron EEC (equilibrium equivalent concentration) by 97% while 80% of total thoron EEC were reduced by 0.2 h -1 filtration rate; meanwhile, the unattached thoron EEC rose significantly by 190, 270, 290%, respectively under 0.4-0.8 h -1 filtration rate, whereas 0.2 h -1 filtration rate increased unattached thoron EEC by 40%. The aerosol number size distribution variation reveals that filtration operation removes smaller particles faster or earlier than the larger ones. The annual effective dose calculated was reduced by 91-92% at a filtration rate of 0.4-0.8 h -1 while 75% reduced at 0.2 h -1 filtration rate after 88 h filtration process. (authors)

  3. Measurement of radon, thoron and their progeny concentrations in the dwellings of Pauri Garhwal, Uttarakhand, India

    International Nuclear Information System (INIS)

    Joshi, Veena; Bijalwan, Pramesh; Rawat, Jasbir; Yadav, Manjulata; Ramola, R.C.; Mishra, Rosaline

    2015-01-01

    It is well known that inhalation of radon, thoron and their progeny contribute more than 50% of natural background radiation dose to human being. The time integrated passive measurements of radon, thoron and their progeny concentrations were carried out in the dwellings of Pauri Garhwal, Uttarakhand, India. The measurements of radon and thoron concentrations were performed by LR-115 detector based single entry Pin-Hole dosimeter while for the measurement of progeny concentrations, LR-115 deposition based DTPS/DRPS technique was used. The experimental techniques and results obtained are discussed in detail. (author)

  4. Concentration of Radon Progeny in Air by Alpha Spectrometry Measurement

    International Nuclear Information System (INIS)

    Acena, M. L.; Crespo, M. T.

    1989-01-01

    The concentration of radon progeny in air has been determined by alpha spectrometry measurement of 214 Po and 318 Po. A known volume of air was passed through a filter, then the alpha activity was directly measured on this filter. (Author) 15 refs

  5. Study of radon progeny distribution and radiation dose rate in the atmosphere

    International Nuclear Information System (INIS)

    Fujinami, Naoto

    2009-01-01

    The absorbed dose rate in air of airborne gamma-ray and the concentration of radon progeny in surface air have been observed continuously in Maizuru, Japan. When data observed on fine days were plotted, with dose rate as ordinate and contraction as abscissa, these points traced with a lapse of time illustrated an anticlockwise looping for each day. This result suggests that the variation of absorbed dose rate lags behind that of concentration of radon progeny; this is due to the delay time incurred as the concentration level gradually varies from ground surface to upper air. Radon progeny concentrations in precipitation and in surface air have been observed there in order to study the relationship between the two concentrations and the influence of precipitation patterns on the concentration in precipitation. Results obtained from analysis of the observed data suggest that radon progeny in precipitation originate mainly from scavenging within the cloud (rainout) and not from that below the cloud (washout). (author)

  6. Daily and seasonal variations of outdoor alpha-activity concentration in Salzburg city/Austria

    International Nuclear Information System (INIS)

    Lettner, H.; Hubmer, A.K.; Rolle, R.; Winkler, R.; Steinhaeusler, F.

    1996-01-01

    Long-term continuous measurements of the atmospheric outdoor alpha-activity concentration have been performed by using a radioaerosol-monitor, roof-mounted 20 m above ground. The alpha-activity concentration was identified to be predominantly attributed to radon progeny. The total alpha-activity covers a range of two orders of magnitude. Three different components of variations could be identified with regard to temporal variations: Short-term diurnal component (daily variation), mid-term component (days to weeks) and long-term component (seasonal variation). Continuous measurements have been recorded since the end of 1993. The results of continuous measurements of the outdoor alpha-activity concentration over a time span from January 1994 to June 1995 are presented. (author)

  7. Multi-parametric approach towards the assessment of radon and thoron progeny exposures

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Rosaline, E-mail: rosaline@barc.gov.in, E-mail: rosaline.mishra@gmail.com; Sapra, B. K. [Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Mayya, Y. S. [Indian Institute of Technology, Mumbai (India)

    2014-02-15

    Conventionally, the dosimetry is carried out using radon and thoron gas concentration measurements and doses have been assigned using assumed equilibrium factors for the progeny species, which is inadequate pertaining to the variations in equilibrium factors and possibly due to significant thoron. In fact, since the true exposures depend upon the intricate mechanisms of progeny deposition in the lung, therefore an integrated approach for the assessment of progeny is essential. In this context, the recently developed deposition based progeny concentration measurement techniques (DTPS: Direct Thoron progeny sensors and DRPS: Direct Radon progeny sensors) appear to be best suited for radiological risk assessments both among occupational workers and general study populations. DTPS and DRPS consist of aluminized mylar mounted LR115 type passive detectors, which essentially detects the alpha particles emitted from the deposited progeny atoms on the detector surface. It gives direct measure of progeny activity concentrations in air. DTPS has a lower limit of detection limit of 0.1 Bq/m{sup 3} whereas that for DRPS is 1 Bq/m{sup 3}, hence are perfectly suitable for indoor environments. These DTPS and DRPS can be capped with 200-mesh type wire-screen to measure the coarse fraction of the progeny concentration and the corresponding coarse fraction deposition velocities as well as the time integrated fine fraction. DTPS and DRPS can also be lodged in an integrated sampler wherein the wire-mesh and filter-paper are arranged in an array in flow-mode, to measure the fine and coarse fraction concentration separately and simultaneously. The details are further discussed in the paper.

  8. A study on genetic variation and selective effect of principal characters of hybrid progenies of macro-mutants in peanut

    International Nuclear Information System (INIS)

    Qiu Qingrong

    1990-01-01

    In order to make good use of macro-mutants, we have studied the law of genetic variation and selective effect on the hybrid progenies of original varieties and of two macro-mutants with steady phenotypes. The results show that the hybrid progenies of the two experimental macro-mutants in the broad-sense heritability and the genetic advance of their main economical characters as well as the effect on selection are better than those of the hybrid progenies of the two original varieties. The selection rate from the macro-mutant hybrid progenies is 72.2% which is higher than that of the hybrid progenies of the two original varieties, and and a new prospecting strain has been obtained

  9. Effect of ventilation on concentrations of indoor radon- and thoron-progeny: Experimental verification of a simple model

    International Nuclear Information System (INIS)

    Sheets, R.W.; Thompson, C.C.

    1993-01-01

    Different models relating the dependence of radon ( 222 Rn)- and thoron ( 220 Rn)-progeny activities on room ventilation rates are presented in the literature. Some of these models predict that, as the rate of ventilation increases, activities of thoron progeny decrease more rapidly than those of radon progeny. Other models predict the opposite trend. In this study alpha activities of the radon progeny, 218 Po, 214 Pb, and 214 Bi, together with the thoron progeny 212 Pb, were measured over periods of several days in two rooms of a closed, heated house. Effective ventilation rates were calculated from measured 214 Pb/ 214 Bi ratios. A simple model in which progeny concentrations decrease by radioactive decay and by dilution with outside air has been used to calculate 212 Pb/ 214 Pb ratios as a function of ventilation rate. Calculated ratios are found to correlate significantly with experimentally-determined ratios (R 2 ∼ 0.5--0.8 at p < 0.005) confirming that, for this house, thoron progeny activities decrease faster than radon progeny activities with increasing rates of ventilation

  10. Long-term determination of airborne concentrations of unattached and attached radon progeny using stacked LR 115 detector with multi-step etching

    International Nuclear Information System (INIS)

    Nikezic, D.; Yu, K.N.

    2010-01-01

    We developed the theoretical basis for long-term determination of airborne concentrations of unattached and attached radon progeny. The work was separated into two parts. First, we showed that (stacked and multiply etched) LR 115 detectors could be used to determine airborne concentrations of the short-lived radon progeny, 218 Po and 214 Bi. The equilibrium factor F between radon and its progeny could then be determined through the use of the reduced equilibrium factor F red . The airborne concentrations of 214 Pb could then be determined. Second, we developed a method based on the airborne concentrations of 218 Po, 214 Pb and 214 Bi to determine the parameters of the Jacobi room model, viz., the ventilation rate λ v , aerosol attachment rate λ a , deposition rate of unattached progeny λ d u and the deposition rate of attached progeny λ d u . With these parameters, the unattached fraction f p of the potential alpha energy concentration could also be determined. Knowledge of f p , together with F, would enable more accurate determination of the effective dose in the human lung.

  11. Radon progeny mitigation using unipolar ion generators

    International Nuclear Information System (INIS)

    Sapra, B.K.; Arun Kumar; Khan, Arshad; Kothalkar, P.S.; Mayya, Y.S.

    2006-01-01

    Unipolar ion generators are often used for reduction of particulate levels in indoor environments. This paper explores the feasibility of their use in reducing radon progeny concentrations in a confined environment. Experiments have been carried out in a 10 m 3 test vessel in which ionizers are suspended in airspace and 226 Ra planchettes are placed as sources of radon. The radon, progeny and aerosol concentrations were estimated prior to and post-ioniser operation in the vessel using standard instruments and techniques. Results showed that the progeny concentrations decreased by a factor of about 10 with a mean life of about 35 min after ioniser was switched on. A mathematical model involving progeny, particle, ion space charge and electric field interaction processes been developed for estimating the various fractions of the progeny concentrations in the presence of the ionizer. The results of the model compared well with the experimental results. This study has a possible application for reducing progeny concentrations in U mines at local scales and specific working areas. (author)

  12. Development of a portable radon progeny monitor

    International Nuclear Information System (INIS)

    Iimoto, Takeshi; Kosako, Toshiso; Sugiura, Nobuyuki

    2000-01-01

    Important nuclides in the radon family contributing to the effective dose are the members of the radon short-life progeny, 218 Po and 214 Po and direct measurement of these progenies is suitable for dosimetry. Survey of the radon progeny concentrations in a number of dwellings and offices is very difficult because we have no convenient instrument for the measurement. At present, radon dosimetry is carried out based on the concentration of the parent radon itself. Therefore, for accurate estimation of public or personal effective dose, it is necessary to develop a facile and portable radon progeny monitor. In this study, a portable radon progeny monitor (PRPM) was designed and developed to automatically estimate the individual progeny concentration in the natural environment. The properties of PRPM were investigated. The dimensions of the entire instrument were 65 x 145 x 170 mm and the total weight was 780 g. The portability of PRPM was much superior to the conventional instrument. The PRPM can operate automatically to estimate individual progeny concentration. All component materials of the monitor were selected based on the data of specified performance, cost performance and availability bon the market. The concentration of individual radon progeny was estimated by the build-up decay. It was concluded that PRPM is much suitable for outdoor study and personal dose estimation, as well as indoor measurement. In the field survey, especially in mines and caverns, PRPM is found as a valuable and convenient instrument. (M.N.)

  13. Radon Progeny in Egyptian Underground Phosphate Mines

    International Nuclear Information System (INIS)

    El-Hady, M.A.; Mohammed, A.; El-Hussein, A.; Ali, A.E.; Ahmed, A.A.

    2001-01-01

    In addition to the workers in uranium mines, the staff of other underground mines, such as workers in underground phosphate mines, can be exposed to 222 Rn and its progeny. In this study the individual radon progeny concentrations were measured in three Egyptian underground phosphate mines to estimate the occupational exposure of the workers at those sites. A filter method was used to measure individual radon progeny concentrations ( 218 Po, 214 Pb and 214 Po). The reported mean values of radon progeny concentrations exceed the action levels which are recommended by ICRP 65 (1993). Based on the measured individual radon progeny concentrations ( 218 Po, 214 Pb and 214 Po) in these mines, the annual effective dose for the workers has been calculated using the lung dose model of ICRP 66 (1994). According to the obtained results, some countermeasures were recommended in this study to minimise these exposure levels. (author)

  14. Measurement of radon progeny concentrations in air by alpha-particle spectrometey

    International Nuclear Information System (INIS)

    Kerr, G.D.

    1975-07-01

    A technique is presented for measuring air concentrations of the short-lived progeny of radon-222 by the use of alpha spectrometry. In this technique, the concentration of RaA, RaB, and RaC are calculated from one integral count of the RaA and two integral counts of the RaC' alpha-particle activity collected on a filter with an air sampling device. The influence of air sampling and counting intervals of time on the accuracy of the calculated concentrations is discussed in the report. A computer program is presented for use with this technique. It is written in the BASIC language. The program will calculate the air concentrations of RaA, RaB, and RaC, and will estimate the accuracy in these calculated concentrations. (U.S.)

  15. Interaction of radon progeny with atmospheric aerosols

    International Nuclear Information System (INIS)

    Morawska, Lidia

    1994-01-01

    The radiological health hazard due to the airborne radon progeny depends on three factors (i) radon concentration in the air, (ii) radon progeny concentration, and (iii) active particle size distribution. Conclusions as to the health hazard cannot be drawn without full understanding of the interaction mechanisms between radon progeny and atmospheric aerosols. The aim of this work was to study the interaction mechanisms between radon progeny, natural environmental aerosols and environmental tobacco smoke (ETS). The experiments were performed under controlled laboratory conditions of radon concentration (1.85 and 3.70 Bq m -3 ), relative humidity (35, 50, 75 and 95%) and ETS generation. The size distribution of radioactivity carrying aerosols was measured using a wire screen diffusion battery system and size distribution of all airborne aerosols using a differential mobility particle sizer. The paper presents and discusses the results of activity size distribution and radon progeny concentration measurements for different environmental conditions. 7 refs., 2 tabs

  16. Bronchial dosimeter for radon progeny

    Energy Technology Data Exchange (ETDEWEB)

    Cheung, T.K.; Yu, K.N.; Nikezic, D.; Haque, A.K.M.M. [City University of Hong Kong, Hong Kong (China); Vucic, D. [Faculty of Technology, University of Nis, Lescovac (Yugoslavia)

    2000-05-01

    Traditionally, assessments of the bronchial dose from radon progeny were carried out by measuring the unattached fraction (f{sub p}) of potential alpha energy concentration (PAEC), the total PAEC, activity median diameters (AMDs) and equilibrium factor, and then using dosimetric lung models. A breakthrough was proposed by Hopke et al. (1990) to use multiple metal wire screens to mimic the deposition properties of radon progeny in the nasal (N) and tracheobronchial (T-B) regions directly. In particular, they were successful in using four layers of 400-mesh wire screens with a face velocity of 12 cm s{sup -1} for the simulation of radon progeny deposition in the T-B region. Oberstedt and Vanmarcke (1995) carried out precise calibrations for the system, and named the system as the 'bronchial dosimeter'. Based on these, Yu and Guan (1998) proposed a portable bronchial dosimeter similar to a normal measurement system for radon progeny or PAEC and consisted of only a single sampler and employed only one 400-mesh wire screen and one filter. However, all these 'bronchial dosimeters' in fact only determined the fraction of potential alpha energy from radon progeny deposited in the T-B region, which required certain assumptions and calculations to further give the final bronchial dose. In the present work, a true 'bronchial dosimeter' was designed, which consisted of three 400-mesh wire screens and a filter. With a face velocity of 11 cm s{sup -1}, the deposition pattern on the wire screens was found to satisfactorily match the variation of the dose conversion factor (in the unit of mSv/WLM) with the size of radon progeny from 1 to 1000 nm. In this way, this bronchial dosimeter directly gave the bronchial dose from the alpha counts recorded on the wire-screens and the filter paper. With the development of this bronchial dosimeter, the present practice of 'dose estimation' from large-scale radon surveys can be replaced by large

  17. Changes of indoor aerosol characteristics and their associated variation on the dose conversion factor due to radon progeny inhalation

    International Nuclear Information System (INIS)

    Tokonami, Shinji; Ishikawa, Tetsuo; Yonehara, Hidenori; Yamada, Yuji; Matsuzawa, Takao; Iimoto, Takeshi

    2003-01-01

    Since the dose conversion factor (hereafter called DCF) due to radon progeny inhalation is strongly dominated by aerosol characteristics in the environment, it is important to understand the air quality for accurate dose assessment. Thus temporal variations on aerosol concentration, its particle size and its related airborne radioactivities were continuously measured in an actual indoor environment with a relatively high radon concentration. The following human activities were added during the observation period: air-conditioning, removal of aerosol with an air cleaner and ventilation. DCFs based on these activities were evaluated with the latest International Commission of Radiological Protection (ICRP) respiratory tract model and were compared among them. Consequently, the present study has shown that operation of air cleaner enhanced the DCF critically because the unattached fraction increased significantly due to removal of aerosols. (author)

  18. Determination of radon and progeny concentrations in Brazilian underground mines

    International Nuclear Information System (INIS)

    Fraenkel, Mario O.; Gouvea, Vandir de Azevedo; Macacini, Jose F.; Cardozo, Katia; Carvalho Filho, Carlos A. de; Lima, Carlos E.

    2008-01-01

    The aim of this work is to present the activities related to the determination of radon and progeny concentrations in underground mines in Brazil. Radon is originated from decay of radium-226 and radium-228 present in rocks. Radon and its short-lived progeny can be retained in the workers pulmonary alveoli, and this way they bring about cancer risk to these mining professionals. The occurrence of high radon concentrations in underground coal and copper mines and the lack of systematic survey motivated CNEN, the regulatory agency, to develop the Radon Project, aiming to aid the formulation of a specific regulation with occupational dose limits consistent with international standards recommended by the International Atomic Energy Agency (IAEA). Dozens of underground mines are currently in operation in the national. It had to be noted that about 50% of these mines are located in Minas Gerais province, and for this reason it was chosen to start the Project. In each underground mine it is installed in selected points passive nuclear track etch radon detectors, type LEXAN and Cr-39, for periods from three to five months. It was also made local measurements with Dose Man Pro detectors from SARAD. The points are chosen according to geological features, radiometric activity and characteristics of prospect development. The determination of radon present in mines has been made in IEN (Nuclear Engineering Institute)/Rio de Janeiro-RJ, LAPOC (Pocos de Caldas Laboratory)/Pocos de Caldas-MG e ESPOA (Porto Alegre Office)/Porto Alegre-RS. Until now it was visited about 35 mines in a universe of about 50 mines, from which 20% showed concentration values higher than international limits (ICRP 65), between 500 and 1500 Bq.m -3 . (author)

  19. Environmental Concentration of Radon and Radon Progeny in a Nuclear Facility in a Decommissioning Stage

    International Nuclear Information System (INIS)

    Ramirez, M. P.; Correa, E.; Sancho, C.

    1999-01-01

    According to the new European Directive 96/29/EURATOM the radiological risk due to natural radionuclides must be consider and the pertinent periodic control must be realized. During the works performed at CIEMAT an estimation of the effective average doses due to Radon inhalation in work places of the installation have been performed. Radon and Radon progeny concentration has been measured in continuous joint whit the meteorological conditions as temperature, pressure and relative humidity. Two different equipment has been used: Alpha-guard whit ionization chamber detector and Eda-wlm-300 whit a semiconductor detector. A passive Radon detector, E-perm has been simultaneously used in the monitoring system. The results obtained during the measuring of Radon and Radon progeny concentrations indoors and estimation of doses have been analyzed and are presented in the paper. (Author) 11 refs

  20. The use of track registration detectors to reconstruct contemporary and historical airborne radon ( sup 2 sup 2 sup 2 Rn) and radon progeny concentrations for a radon-lung cancer epidemiologic study

    CERN Document Server

    Steck, D J

    1999-01-01

    Epidemiologic studies that investigate the relationship between radon and lung cancer require accurate estimates for the long-term average concentrations of radon progeny in dwellings. Year-to-year and home-to-home variations of radon in domestic environments pose serious difficulties for reconstructing an individual's long-term radon-related exposure. The use of contemporary radon gas concentrations as a surrogate for radon-related dose introduces additional uncertainty in dose assessment. Studies of glass exposed in radon chambers and in a home show that radon progeny deposited on, and implanted in, glass hold promise for reconstructing past radon concentrations in a variety of atmospheres. We developed an inexpensive track registration detector for the Iowa Radon Lung Cancer Study (IRLCS) that simultaneously measures contemporary airborne radon concentrations, surface deposited alpha activity density, and implanted sup 2 sup 1 sup 0 Po activity density. The implanted activity is used to reconstruct the cum...

  1. Control of respirable particles and radon progeny with portable air cleaners

    International Nuclear Information System (INIS)

    Offermann, F.J.; Sextro, R.G.; Fisk, W.J.; Nazaroff, W.W.; Nero, A.V.; Revzan, K.L.; Yater, J.

    1984-02-01

    Eleven portable air cleaning devices have been evaluated for control of indoor concentrations of respirable particles and radon progeny. Following injection of cigarette smoke and radon in a room-size chamber, decay rates for particles and radon progeny concentrations were measured with and without air cleaner operation. Particle concentrations were obtained for total number concentration and for number concentration by particle size. In tests with no air cleaner the natural decay rate for cigarette smoke was observed to be 0.2 hr -1 . Air cleaning rates for particles were found to be negligible for several small panel-filters, a residential ion-generator, and a pair of mixing fans. The electrostatic precipitators and extended surface filters tested had significant particle removal rates, and a HEPA-type filter was the most efficient air cleaner. The evaluation of radon progeny control produced similar results; the air cleaners which were effective in removing particles were also effective in removing radon progeny. At low particle concentrations plateout of the unattached radon progeny is an important removal mechanism. Based on data from these tests, the plateout rate for unattached progeny was found to be 15 hr -1 . The unattached fraction and the overall removal rate due to deposition of attached and unattached nuclides have been estimated for each radon decay product as a function of particle concentration. While air cleaning can be effective in reducing total radon progeny, concentrations of unattached radon progeny can increase with increasing air cleaning. 39 references, 26 figures, 9 tables

  2. Wind direction correlated measurements of radon and radon progeny in atmosphere: a method for radon source identification

    International Nuclear Information System (INIS)

    Akber, R.A.; Pfitzner, J.; Johnston, A.

    1994-01-01

    This paper describes the basic principles and methodology of a wind direction correlated measurement technique which is used to distinguish the mine-related and background components of radon and radon progeny concentrations in the vicinity of the ERA Ranger Uranium Mine. Simultaneous measurements of atmospheric radon and radon progeny concentrations and wind speed and direction were conducted using automatic sampling stations. The data were recorded as a time series of half hourly averages and grouped into sixteen 22.5 degrees wind sectors. The sampling interval and the wind sector width were chosen considering wind direction variability (σ θ ) over the sampling time interval. The data were then analysed for radon and radon progeny concentrations in each wind sector. Information about the wind frequency wind speed seasonal and diurnal variations in wind direction and radon concentrations was required for proper data analysis and interpretation of results. A comparison with model-based estimates for an identical time period shows agreement within about a factor of two between the two methods. 15 refs., 1 tab., 5 figs

  3. Radon progeny distribution in cylindrical diffusion chambers

    International Nuclear Information System (INIS)

    Pressyanov, Dobromir S.

    2008-01-01

    An algorithm to model the diffusion of radioactive decay chain atoms is presented. Exact mathematical solutions in cylindrical geometry are given. They are used to obtain expressions for the concentrations of 222 Rn progeny atoms in the volume and deposited on the wall surface in cylindrical diffusion chambers. The dependence of volume fractions of 222 Rn progeny and chamber sensitivity on the coefficient of diffusion of 222 Rn progeny atoms in air is modeled.

  4. FOLIAR NUTRIENT CONTENTS AND FRUIT YIELD IN CUSTARD APPLE PROGENIES

    Directory of Open Access Journals (Sweden)

    Paulo Sérgio Lima e Silva

    2009-01-01

    Full Text Available Foliar nutrient contents are evaluated in several fruit trees with many objectives. Leaf analysis constitutes a way of evaluating the nutritional requirements of crops. Due to the positive impact that fertilizers have on crop yields, researchers frequently try to evaluate the correlations between yield and foliar nutrient contents. This work's objective was to present fruit yields from the 4th to the 6th cropping seasons, evaluate foliar nutrient contents (on the 5th cropping season, and estimate the correlations between these two groups of traits for 20 half-sibling custard apple tree progenies. The progenies were evaluated in a random block design with five replicates and four plants per plot. One hundred leaves were collected from the middle third of the canopy (in height of each of four plants in each plot. The leaves were collected haphazardly, i.e., in a random manner, but without using a drawing mechanism. In the analysis of variance, the nutrient concentrations in the leaves from plants of each plot were represented by the average of four plants in the plot. Fruit yield in the various progenies did not depend on cropping season; progeny A4 was the most productive. No Spearman correlation was found between leaf nutrient concentrations and fruit yield. Increased nutrient concentrations in the leaves were progeny-dependent, i.e., with regard to Na (progenies FE5 and JG1, Ca (progeny A4, Mg (progeny SM7, N (progeny A3, P (progeny M, and K contents (progeny JG3. Spearman's correlation was negative between Na-Mg, Na-Ca, and Mg-P contents, and positive between Mg-Ca and N-K contents.

  5. Measurements of indoor radon and radon progeny in Mexico City

    International Nuclear Information System (INIS)

    Cheng, Y.S.; Rodriguez, G.P.

    1996-01-01

    Indoor radon has been a public concern associated with increased lung cancer risks. Radon decay products interact with indoor aerosols to form progeny with different size distributions, which may influence the lung dosimetry when the progeny are inhaled. Air pollution in Mexico City is a serious problems with high particulate concentrations, but there are few reports of indoor radon measurement. The purposes of this study were to measure the aerosol concentration, radon concentration, and radon activity size distribution in the living area of three houses in Mexico City. The radon concentration was monitored by a RGM-3 radon gas monitor (Eberline, Inc., Santa Fe, NM). A graded diffusion battery was used to determine the progeny concentration and activity size distribution. The concentration and size distribution of the indoor aerosols were monitored by a quartz, crystal microbalance cascade impactor. Our measurements showed high concentrations of indoor aerosols (20-180 gg m -3 ). However, the radon concentrations-were low ( -1 ), but showed a clear diurnal pattern with peak concentrations from 2-10 AM. The activity size distributions of radon progeny were trimodal, with peaks of 0.6 nm, 4-5 nm, and 100 rim. Most activities were associated with large particle sizes. Our results indicated that indoor radon concentration was not high, due in part to a relatively high air exchange with outdoor air. The high aerosol concentration may also play an important part in the activity size distribution of radon progeny

  6. Intra-specific variations in expression of stress-related genes in beech progenies are stronger than drought-induced responses.

    Science.gov (United States)

    Carsjens, Caroline; Nguyen Ngoc, Quynh; Guzy, Jonas; Knutzen, Florian; Meier, Ina Christin; Müller, Markus; Finkeldey, Reiner; Leuschner, Christoph; Polle, Andrea

    2014-12-01

    Rapidly decreasing water availability as a consequence of climate change is likely to endanger the range of long-lived tree species. A pressing question is, therefore, whether adaptation to drought exists in important temperate tree species like European beech (Fagus sylvatica L.), a wide-spread, dominant forest tree in Central Europe. Here, five beech stands were selected along a precipitation gradient from moist to dry conditions. Neutral genetic markers revealed strong variation within and little differentiation between the populations. Natural regeneration from these stands was transferred to a common garden and used to investigate the expression of genes for abscisic acid (ABA)-related drought signaling [9-cis-epoxy-dioxygenase (NCED), protein phosphatase 2C (PP2C), early responsive to dehydration (ERD)] and stress protection [ascorbate peroxidase (APX), superoxide dismutase (SOD), aldehyde dehydrogenase (ALDH), glutamine amidotransferase (GAT)] that are involved in drought acclimation. We hypothesized that progenies from dry sites exhibit constitutively higher expression levels of ABA- and stress-related genes and are less drought responsive than progenies from moist sites. Transcript levels and stress responses (leaf area loss, membrane integrity) of well-irrigated and drought-stressed plants were measured during the early, mid- and late growing season. Principal component (PC) analysis ordered the beech progenies according to the mean annual precipitation at tree origin by the transcript levels of SOD, ALDH, GAT and ERD as major loadings along PC1. PC2 separated moist and drought treatments with PP2C levels as important loading. These results suggest that phosphatase-mediated signaling is flexibly acclimated to the current requirements, whereas stress compensatory measures exhibited genotypic variation, apparently underlying climate selection. In contrast to expectation, the drought responses were less pronounced than the progeny-related differences and the

  7. Genetic Variation Among Open-Pollinated Progeny of Eastern Cottonwood

    Science.gov (United States)

    R. E. Farmer

    1970-01-01

    Improvement programs in eastern cottonwood (Populus deltoides Bartr.) are most frequently designed to produce genetically superior clones for direct commercial use. This paper describes a progeny test to assess genetic variability on which selection might be based.

  8. Growth variation and heritability in a second-generation Eucalyptus urophylla progeny test at Lad Krating Plantation, Chachoengsao province, Thailand

    Directory of Open Access Journals (Sweden)

    Lucky Nhlanhla Dlamini

    2017-06-01

    Full Text Available In Thailand, Eucalyptus urophylla was introduced with the main purpose of supplying raw material for pulp and chip wood production. The demand for genetically improved seed is increasing to support high productivity plantation establishment. One of the tree improvement activities established to meet the high demand for improved seed was a second generation progeny test at Lad Krating Plantation, Thailand to provide the best material for the successful plantation program. The aim of the current study was to compare growth variation of the first and second generation of Eucalyptus urophylla progeny that could provide information on suitable families for improved quality seed. The progeny test comprised the best 45 half-sib families selected from 80 half-sib families of the first-generation progeny test. The design of the progeny test was a randomized and complete block design (16 trees/plot × 45 plots/block × 9 blocks, with 4 rows of 4 trees at a spacing of 2 m × 1 m. Growth was assessed at age 3 yr. The average height and diameter at breast height over bark (DBH, was 13.72 m, and 8.75 cm, respectively. There were highly significant (p < 0.01 differences among provenances and families in both height and DBH. The individual heritability values for height and DBH were 0.48 and 0.60, respectively. The family heritability values for height and DBH were 0.98 and 0.99, respectively. These 45 half-sib families proved to be genetically superior ensuring higher productivity and contributing to the success of the Forest Industry Organization plantation at Lad Krating.

  9. Concentration of Radon, thoron and their progeny levels in different types of floorings, walls, rooms and building materials

    International Nuclear Information System (INIS)

    Sathish, L. A.; Nagaraja, K.; Ramanna, H. C.; Nagesh, V.; Sundareshan, S.

    2009-01-01

    Radon, thoron and their progenies are the most important contributions to human exposure from natural sources. Radon exists in soil gas, building materials, Indoor atmosphere etc. Among all the natural sources of radiation dose to human beings, inhalation of radon contributes a lot. The work presented here emphasizes the long term measurements of radon, thoron and their progeny concentrations in about 100 dwellings using solid state nuclear track detectors. Materials and Methods: Measurements were made using dosimeters and the concentrations were estimated by knowing the track density of films through spark counter, and sensitivity factor for bare, filter and membrane films. Results: Presence of radon and thoron in houses is the effect of several aspects such as the activity concentrations of uranium, radium and thorium in the local soil, building materials, ventilation of houses and also entry of radon into houses through the cracks in floor/wall. Conclusion: The observations reveal that the concentrations of radon and/or thoron are relatively higher in granite than in concrete, cement and bricks. In continuation to this the concentration observed in bathrooms is more compared to kitchen bedroom and living rooms. This study discloses that the residential rooms of good ventilation will avoid the health hazards due to radon and its rich materials.

  10. ARTICLE - Inbreeding depression in castor bean (Ricinus communis L. progenies

    Directory of Open Access Journals (Sweden)

    Milton Krieger

    2012-12-01

    Full Text Available The purpose of this study was to investigate inbreeding depression (DE in castor bean. From a population derived from the Guarani cultivar, 60 mother plants were sampled. Three types of progenies were obtained from each one: from self-pollination (AU, from crosses (CR and from open pollination (PL. Grain yield of the progenies was evaluated in two locations. There was a strong interaction of progenies x locations, which led to obtaining estimates within each location. Broad variation was observed in inbreeding depression, with mean values of 6.7% and 13.4%, comparing AU progenies with PL progenies. It was observed that the population has high potential for selecting promising inbred lines. The frequency of mother plants generating progenies with simultaneous high general combination capacity and low inbreeding depression was low. Recurrent selection will increase the occurrence of parent plants associating these two properties, which is necessary for obtaining superior synthetic varieties.

  11. Distribution characteristics of radon and its progeny in blind roadway with forced ventilation

    International Nuclear Information System (INIS)

    Ye Yongjun; Zhou Xinghuo; Li Xiangyang; Zhong Yongming; Liu Dong; Ding Dexin

    2012-01-01

    The blind roadway is not only the important workplaces, but also is important site of radon and its progeny generating and gathering, it is an important guiding significance for ventilation protection design to study distribution characteristics of radon and its progeny in blind roadway. Therefore, at first, the paper expounded the mathematical relationship between radon activity concentration with alpha potential concentration of radon progeny. Then, analyzed the sources of radon and its progeny, and established mathematical calculation model of Distribution characteristics of radon and its progeny in blind roadway with forced ventilation, respectively. Finally, using mathematical calculation models to analyze the influence law of multiple factors. (authors)

  12. Cellular lung dosimetry for inhaled thoron progeny: comparison with radon progeny

    International Nuclear Information System (INIS)

    Abd El-Hady, M.; Hofmann, W.; Balashazy, I.

    1998-01-01

    Recently an analytical method was developed to compute radiation doses deposited by 222 Rn progeny alpha particles in 1 μm spheres located at different depths in bronchial epithelium. The same method was now applied to alpha particles emitted from 220 Rn progeny deposited in bronchial airway surfaces. Results of the computations are presented in graphs. The mean cellular doses imparted by 220 Rn progeny to basal and secretory cell nuclei were compared with those produced by 222 Rn progeny; due to differences in alpha energies, radon progeny doses were found to be generally higher than those for thoron progeny. (A.K.)

  13. Radon Progeny In Underground Phosphate Mines and Their Activity Distributions In Human Lung

    International Nuclear Information System (INIS)

    Abd El-Hady, M.; Mohammed, A.; El-Hussein, A.; Ali, A.E.; Ahmed, A.A.

    2001-01-01

    In addition to workers in uranium mines, the staff of other underground mines, such as worker in underground phosphate mines, Can be exposed to 222 Rn and its progeny. In this study the individual radon progeny concentrations were measured in three Egyptian underground phosphate mines to estimate the occupational exposure to the workers in those sites. Active techniques are employed to fulfill the objective of measuring individual radon progeny concentrations (C RaA , C RaB and C RaC ). The mean reported values of radon progeny concentrations exceed the action levels recommended by ICRP 65 (1993). Based on the physical properties of attached radon progeny aerosol and physiological parameters for heavy work activity which recommended by ICRP 66 (1994). the deposition fraction for each airway generation was calculated. From the measured individual radon progeny concentrations in these mines and the calculated values of deposition fractions, the surface activity distribution per generation were calculated in human respiratory system (BB and regions). The maximum values of these activities were found in the upper bronchial airway generations. According to the obtained results, some of the corrective actions were recommended in this study

  14. Genetic variation of phytochemical compounds in progenies of Ilex paraguariensis St. Hil.

    Directory of Open Access Journals (Sweden)

    Euclides Lara Cardozo Junior

    2009-01-01

    Full Text Available Mate (Ilex paraguariensis St. Hil contains phytochemical compounds capable of preventing a number of healthproblems. Knowledge on the genetic contribution to the variability in these compounds can help to obtain mate progenies withhigher levels thereof in breeding programs. The composition of triterpene saponins, methylxanthines, chlorogenic acid andthe antioxidant activity of eight mate progenies were evaluated. Significant differences among progenies were verified incontents of triterpene saponins (0.003-0.080%, caffeine (0.226-1.377%, theobromine (0.176-0.831%, and chlorogenicacid (1.344-2.031% and in antioxidant activity (31.251-51.406%. The contents of theobromine were found to be negativelycorrelated with saponins and caffeine, and caffeine with chlorogenic acid, while theobromine was positively correlated withchlorogenic acid. The heritability values for saponins (75.09%, caffeine (75.19%, theobromine (66.87%, chlorogenic acid(52.86% and antioxidant activity (67.75% indicate the possibility of genetic gain in selection for these traits.

  15. An assessment method of dose equivalent due to indoor 220Rn progeny by using 220Rn concentration measured at a 20 cm distance from wall

    International Nuclear Information System (INIS)

    Iida, T.; Ikebe, Y.; Okamoto, K.; Guo, Q.; Yamasaki, T.

    1996-01-01

    A pair of passive cup monitors with a different air exchange openings was developed for measuring simultaneously 222 Rn and 220 Rn concentrations. Indoor 220 Rn concentrations were very high in traditional Japanese dwellings with soil walls. The 220 Rn concentration decreases exponentially with the distance from wall. The effective diffusion coefficient of 220 Rn in dwelling and the exhalation rate of 220 Rn from wall were evaluated from the distribution of the 220 Rn concentrations. Then, indoor 220 Rn progeny concentration could be estimated from the 220 Rn concentration at a 20 cm distance from wall. From the results of the surveys. the average annual effective dose equivalent due to 220 Rn progeny was expected to be 0.67 mSv/year in the traditional Japanese dwellings. (author)

  16. Behavior toxicity to Caenorhabditis elegans transferred to the progeny after exposure to sulfamethoxazole at environmentally relevant concentrations

    Institute of Scientific and Technical Information of China (English)

    Zhenyang Yu; Lei Jiang; Daqiang Yin

    2011-01-01

    Sulfamethoxazole (SMX) is one of the most common detected antibiotics in the environment. In order to study whether SMX can affect behavior and growth and whether these effects could be transferred to the progeny, Caenorhabditis elegans was exposed at environmentally relevant concentrations for 24, 48, 72 and 96 hr, respectively. After exposure, the exposed parent generation (Po) was measured for behavior and growth indicators, which were presented as percentage of controls (POC). Then their corresponding unexposed progeny (F1) was separated and measured for the same indicators. The lowest POC for Po after 96 hr-exposure at 100 mg/L were 37.8%, 12.7%, 45.8% and 70.1% for body bending frequency (BBF), reversal movement (RM), Omega turns (OT) and body length (BL), respectively. And F1 suffered defects with the lowest POC as 55.8%, 24.1%, 48.5% and 60.7% for BBF, RM, OT and BL, respectively. Defects in both Po and F1 showed a time- and concentration-dependent fashion and behavior indicators showed better sensitivity than growth indicator. The observed effects on F1 demonstrated the transferable properties of SMX. Defects of SMX at environmental concentrations suggested that it is necessary to perform further systematical studies on its ecological risk in actual conditions.

  17. Investigation of the exposure to radon and progeny in the thermal spas of Loutraki (Attica-Greece): Results from measurements and modelling

    International Nuclear Information System (INIS)

    Nikolopoulos, Dimitrios; Vogiannis, Efstratios; Petraki, Ermioni; Zisos, Athanasios; Louizi, Anna

    2010-01-01

    Radon and progeny ( 218 Po, 214 Pb, 214 Bi and 214 Po) in thermal spas are well known radioactive pollutants identified for additional radiation burden of patients due to the activity concentration peaks which appear during bath treatment or due to drinking of waters of high radon content. This burden affects additionally the working personnel of the spas. The present paper has focused on the thermal spas of Loutraki (Attica-Greece). The aim was the investigation of the health impact for patients and working personnel due to radon and progeny. Attention has been paid to radon and progeny transient concentration peaks (for bath treatment) and to radon of thermal waters (both for bath treatment and drinking therapy). Designed experiments have been carried out, which included radon and progeny activity concentration measurements in thermal waters and ambient air. Additionally, published models for description of radon and progeny transient concentration peaks were employed. The models were based on physicochemical processes involved and employed non linear first order derivative mass balance differential equations which were solved numerically with the aid of specially developed computer codes. The collected measurements were analysed incorporating these models. Results were checked via non linear statistical tests. Predictions and measurements were found in close agreement. Non linear parameters were estimated. The models were employed for dosimetric estimations of patients and working personnel. The effective doses of patients receiving bath treatment were found low but not negligible. The corresponding doses to patients receiving potable treatment were found high but below the proposed international limits. It was found that the working personnel are exposed to considerable effective doses, however well below the acceptable limits for workers. It was concluded that treatment and working in the Loutraki spas leads to intense variations of radon and progeny and

  18. Measurement of radon and thoron progenies in Coimbatore

    International Nuclear Information System (INIS)

    Sivakumar, R.; Selvasekarapandian, S.; Mahendraprasad, M.; Meenakshisundaram, V.; Santhanam, R.; Raghunath, V.M.

    2001-01-01

    The radon and thoron daughter concentrations have been measured in different dwellings of Coimbatore city by grab sampling method and two count. It has been found that the radon daughter concentration varies from 0.5 to 10.5 mWL with mean value of 2.9 mWL and that of thoron progeny is from 0.7 to 16.3 mWL with mean value of 3.8 mWL. The average annual effective dose equivalent due to radon daughters is found to be 1.3 mSv and that of thoron progeny is 3.8 mSv. (author)

  19. Development of an aerosol chamber for calibration of 220Rn progeny detectors

    Science.gov (United States)

    Sorimachi, Atsuyuki; Ishikawa, Tetsuo; Tokonami, Shinji

    2014-09-01

    This paper describes an aerosol chamber system that can be used for calibrations and performance experiments of passive 220Rn progeny detectors. For the purpose of this study, an aerosol generation system using carnauba wax as the aerosol material was mounted into the 220Rn chamber. We used the chamber to measure characteristics of the equilibrium factor (F) of 220Rn and unattached fraction (fp) of 220Rn progeny, which are important parameters for dose estimation. The first experiment showed that continuous and stable generation of the unattached and aerosol-attached 220Rn progeny concentrations was obtained. We observed that the spatial distributions in the chamber of the vertical profiles of the unattached and aerosol-attached 220Rn progeny concentrations were homogeneous, as were the particle number concentration and count median diameter. The values of F and fp and their characteristics observed in this study were in the same range as the values reported from indoor measurements. We found that the characteristics of F and fp were dependent on the aerosol conditions (particle diameter and particle number concentration).

  20. Radon and thoron progeny levels in air samples at Udagamandalam region of Nilgiris in India

    International Nuclear Information System (INIS)

    Manikandan, N.M.; Selvasekarapandian, S.; Sivakumar, R.; Raghunath, V.M.; Sundaram, V.M.; Santhanam, S.

    2002-01-01

    Measurement of concentration of radon and thoron daughter products in various indoor environment covering four seasons of a year in Udagamandalam Taluk of Nilgiris biosphere has been carried out using a high volume air sampler to assess the inhalation dose to the population which delivers higher dose than the radon and thoron gas alone. The potential alpha-energy concentrations of the radon and thoron progeny ranged from 0.97 to 12.72 mWL and from 1.63 to 15.83 mWL with a geometric mean of 6.02 and 7.89 mWL, respectively, taking all seasons into account. These measurements have yielded a wealth of data on the variation among the indoor radon and thoron progeny in various places during different seasons. The radon and thoron progeny levels are higher in winter seasons and are less in summer season with autumn and spring data lie in between winter and summer. Using the dose conversion factor for indoor exposures given in UNSCEAR 93 report the internal equivalent dose to the inhalation of radon progeny is evaluated to be 1357 μSv x y -1 and the corresponding annual effective dose equivalent value has been found to be 2.13 mSv x y -1 . It can be observed that the mean value of radon is higher than the Indian average. Also it is found the radon and thoron progeny levels are higher in the case of houses built with rock and granite and in tiled type houses of nearly 100 years old. The levels are less in the case of houses built with brick and cement. The observed results for different types of houses and seasons are discussed in this paper. (author)

  1. Progeny reproduction

    International Nuclear Information System (INIS)

    Mashneva, N.I.

    1984-01-01

    Studies on clarification of importance of different harmful factors of radiation and chemical nature on the function of progeny reproduction, growth and development are presented. Intake of radionuclides to organism, of white mices and rats in concentrations corresponding to 10 6 PCsub(s) ( 90 Sr, 210 Po, 210 Pb and other) is shown to result in 100% sterility of females, 10 5 -10 4 PCsub(s) concentrations cause damaging effect of different degrees of expression at later stages of effect. Smaller contents of radionuclides (10 3 -10 2 PCsub(s)) did not result in noticeable changes in reproductivity of animals. Similar regularities were observed under effect of different concentrations of chemical agent. Some peculiarities of animal physiology should be taken into account to obtain data of estimation of damaging effect of harmful factors on reproduction function

  2. Concentration of Radon Progeny in Air by Alpha Spectrometry Measurement; Medida de los descendientes del radon en aire por Espectrometria Alfa

    Energy Technology Data Exchange (ETDEWEB)

    Acena, M L; Crespo, M T

    1989-07-01

    The concentration of radon progeny in air has been determined by alpha spectrometry measurement of 214 Po and 318 Po. A known volume of air was passed through a filter, then the alpha activity was directly measured on this filter. (Author) 15 refs.

  3. Dosimetry of inhaled radon and thoron progeny

    International Nuclear Information System (INIS)

    James, A.C.

    1994-06-01

    This chapter reviews recent developments in modeling doses received by lung tissues, with particular emphasis on application of ICRP's new dosimetric model of the respiratory tract for extrapolating to other environments the established risks from exposure to radon progeny in underground mines. Factors discussed include: (1) the influence of physical characteristics of radon progeny aerosols on dose per unit exposure, e.g., the unattached fraction, and the activity-size distributions of clustered and attached progeny; (2) the dependence of dose on breathing rate, and on the exposed subject (man, woman or child); (3) the variability of dose per unit exposure in a home when exposure is expressed in terms of potential α energy or radon gas concentration; (4) the comparative dosimetry of thoron progeny; and (5) the effects of air-cleaning on lung dose. Also discussed is the apparent discrepancy between lung cancer risk estimates derived purely from dosimetry and the lung cancer incidence observed in the epidemiological studies of radon-exposed underground miners. Application of ICRP's recommended risk factors appears to overestimate radon lung-cancer risk for miners by a factor of three. ''Normalization'' of the calculated effective dose is therefore needed, at least for α dose from radon and thoron progeny, in order to obtain a realistic estimate of lung cancer risk

  4. Direct progeny detection techniques and random epidemiology

    International Nuclear Information System (INIS)

    Mayya, Y.S.; Mishra, Rosaline; Sapra, B.K.

    2015-01-01

    Over the past 40 years, there has been considerable progress in the measurements methods and their application to the estimates of risks due to radon among general populations. The previous decade saw major development in this regard. It was the direct estimate of indoor radon risk from epidemiological studies in Europe and North America. These were important findings that demonstrated the presence of lung cancer risks at residential radon levels supplementing the generally used risks estimates at high exposures obtained from uranium miner's data. The residential radon epidemiological studies largely used radon concentration as a measure of exposure. The exposure to decay products, which are primarily the dose givers, are assumed to be proportional to the measured gas concentrations. Also, the presence of thoron was neglected in these studies. Although several corrections have appeared to these assessments, the question of variability of actual decay product exposures has largely remained unaddressed. In order to circumvent this limitation, passive techniques were developed to estimate the decay product concentrations directly using deposition monitors. These are based on detecting the alpha particles from decay products deposited on an absorber mounted LR-115 detectors. Known as Direct radon, and Thoron Progeny sensors (DRPS/DTPS), these have been further refined to separate fine fraction from the coarse fraction by wire-mesh capping techniques. Large number environmental calibration exercises and field data generation has been carried out on the progeny concentrations in Indian and some European environments. The development of progeny sensors offers a new tool for future epidemiology. Since in the Indian context, there exist no radon related epidemiological estimates of risk, it is time one conducts large scale studies to seek possible correlations between DRPS/DTPS data and lung cancer risks. While epidemiological studies in High background radiation areas

  5. An intercomparison between gross α counting and gross β counting for grab-sampling determination of airborne radon progeny and thoron progeny

    International Nuclear Information System (INIS)

    Papp, Z.

    2006-01-01

    The instantaneous values of the airborne activity concentrations of radon progeny and thoron progeny have been determined 34 times in a closed and windowless room in a cellar using two independent grab-sampling methods in order to compare the performance of the methods. The activity concentration of radon ( 222 Rn) was also measured and it varied between 200 and 650 Bq m -3 . Two samples of radon and thoron progeny were collected simultaneously from roughly the same air volume by filtering. For the first method, the isotopes were collected on membrane filter and gross α counting was applied over several successive time intervals. This method was a slightly improved version of the methods that are applied generally for this reason for decades. For the second method, the isotopes were collected on glass-fibre filter and gross β counts were registered over several time intervals. This other method was developed a few years ago and the above series of measurements was the first opportunity to make an intercomparison between it and another similar method based on α counting. Individual radon progeny and thoron progeny activity concentrations (for the isotopes 218 Po, 214 Pb, 214 Bi and 212 Pb) were evaluated by both methods. The detailed investigation of the results showed that the systematic deviation of the methods is small but significant and isotope-dependent. The weighted averages of the β/α activity concentration ratios for 218 Po, 214 Pb, 214 Bi, EEDC 222 (Equilibrium-Equivalent Decay-product Concentration of radon progeny) and 212 Pb were 0.99±0.03, 0.90±0.02, 1.03±0.02, 0.96±0.02 and 0.80±0.03, respectively. The source of the systematic deviation is probably the inaccurate knowledge of the counting efficiencies mainly in the case of the α-counting method. A significant random-type difference between the results obtained with the two methods has also been revealed. For example, the β/α ratio for EEDC 222 varied between 0.81±0.01 and 1.22±0

  6. Development of calibration facility for radon and its progenies at NIM (China)

    International Nuclear Information System (INIS)

    Liang, J.C.; Liu, H.R.; Zhang, M.; Zheng, P.H.; Guo, Q.J.; Yang, Z.J.; Li, Z.S.; Zhang, L.

    2015-01-01

    Accurate measurement of radon and its progenies is the basis to control the radon dose and reduce the risk of lung cancer caused. The precise calibration of measuring instrument is an important part of the quality control of measurements of the concentration of radon and radon progenies. To establish Chinese national standards and realise reliable calibrations of measuring instrument for radon and its progenies, a radon chamber with regulation capability of environmental parameters, aerosol and radon concentrations was designed and constructed at National Institute of Metrology (NIM). The chamber has a total volume of ∼20 m 3 including an exposure volume of 12.44 m 3 . The radon concentration can be controlled from 12 Bq m -3 to the maximum of 232 kBq m -3 . The regulation range of temperature, relative humidity and aerosol are 0.66-44.39 deg. C, 16.4-95 %RH and 10 2 -10 6 cm -3 , respectively. The main advantages of the NIM radon chamber with respect to maintaining a stable concentration and equilibrium factor of radon progenies in a wide range through automatic regulation and control of radon and aerosol are described. (authors)

  7. Long-lived 222Rn progeny concentrations in ground level air of Milan

    International Nuclear Information System (INIS)

    Marcazzan, G.M.; Valli, G.; Vecchi, R.; Bocelli, R.

    2002-01-01

    Short-lived (2 18P o, 2 14P b, 2 14B i, 2 14P o) as well as long-lived (2 10P b, 2 10B i, 2 10P o) Radon's decay products in atmosphere are due to the 2 22R n exhalation from the continental Earth's crust, where it is generated in the 2 38U decay series. The measurement of the radionuclides concentration in the atmosphere - in addition to yielding valuable data for radioprotection purposes and for assessing the environmental impact of natural radioactivity - can provide information on atmospheric thermodynamic conditions as well as on atmospheric processes that involve aerosols such as transport, dispersion, removal rates and residence time. In particular, the concentration ratio of 2 10P b with other Radon's daughters can be used to obtain information on mean residence time of aerosols (Poet et al., 1972; Rangarajan, 1992; Gaggeler et al., 1995). Continuous measurements of hourly concentration of Radon and its short-lived progeny are routinely carried out in Milan by our group, and the temporal behaviour comes out a suitable tracer of atmospheric stability conditions and a local index of the evolution of the mixing layer height (Marcazzan et al., 1993; Marcazzan et al., 1997). The aim of this work was to measure the concentration and temporal behaviour of 2 10P b on a weekly and a monthly scale at ground level in the urban area of Milan and to get reliable measurements on the annual average concentration for the implementation of the existing data base (Preiss et al., 1996)

  8. Study of indoor radon, thoron and their progeny concentration levels in the surrounding areas of Mangaldoi, Assam

    International Nuclear Information System (INIS)

    Deka, P.C.; Sarkar, S.; Goswami, T.D.; Sarma, B.K.

    2006-01-01

    Natural sources contribute a significant percentage of radiation towards the total radiation exposure that humans receive. The majority of this natural radiation is harmless to humans in the ambient environment. However, radon, a major component of the natural radiation that humans are exposed to (greater than sixty percent), can pose a threat to the public health when radon gas accumulates in poorly ventilated residential and occupational settings. Measurements of concentration of radon, thoron and their decay products in various indoor environment covering four seasons of a year were carried out using the passive time-integrated method by employing LR-15 type II detectors in plastic twin-chamber dosimeter cups. The estimated indoor radon levels for well ventilated houses varied from a minimum value of 25.2 Bq.m -3 to a maximum of 80J Bq.m -3 with an annual geometric mean of 46.9 Bq.m -3 and that for poorly ventilated houses varied from a minimum value of 46.8 Bq.m -3 to a maximum of 146.8 Bq.m -3 with the annual geometric mean of 82 .2 Bq.m -3 . The thoron levels in well ventilated houses were also varied from a minimum value of 4.9 Bq.m -3 to a maximum of 21.5 Bq.m -3 with an annual geometric mean of 10.5 Bq.m -3 and that for poorly ventilated houses varied from a minimum of 6.3 Bq.m -3 to a maximum value of 29.2 Bq.m -3 with the annual geometric mean of 14.1 Bq.m -3 . Thus it is seen that both radon and thoron levels are higher in poorly ventilated houses than in well-ventilated houses. The ranges of radon and thoron progeny levels for well ventilated houses were 0.10 mWL to 0.58 mWL with an annual geometric mean of 0.21 mWL and 0.01 mWL to 0.06 mWL with an annual geometric mean of 0.03 mWL respectively. Similar variation was also observed in poorly ventilated houses. In poorly ventilated houses, the radon and thoron progeny levels varied between 0.16 mWL and 1.61 mWL with an annual geometric mean of 0.41 mWL and 0.02 to 029 mWL with the annual geometric mean

  9. Levels of radon gas concentration and progeny in homes of Potosi City, Bolivia to 4000 m

    International Nuclear Information System (INIS)

    Mamani M, R.; Claros J, J.; Vasquez A, R.

    2015-10-01

    Full text: In this work the presence of radon gas was determined, which is a radioactive contaminant that comes from underground, able to penetrate the houses. The danger is that when mixed air and when inhaled can cause serious damage to the lungs, for the short life time that has radon and progeny for decay, damaging the pulmonary alveoli and reducing breathing capacity of the habitants, then causing polycythemia in some cases. The study was carried out in homes in the city of Potosi, Bolivia located at 4000 m. The quantification of radon gas and progeny was performed with the equipment Alpha-Zaeller-2 (Az-2), quantification was realized in 6 zones of the city of Potosi, chosen randomly. In each zone were carried out measurements in 40 homes (2 rooms more permanent), both day and night, for a period of 3 days in two different seasons and with concentrations of average humidity of 20, 50 and 80%. The values obtained for each period vary depending on the season and 30 to 50% of the allowable values given by the EPA and Who for housing. (Author)

  10. Factors affecting daughters distribution among progeny testing Holstein bulls

    Directory of Open Access Journals (Sweden)

    Martino Cassandro

    2012-01-01

    Full Text Available The aim of this study was to investigate factors influencing the number of daughters of Holstein bulls during the progeny testing using data provided by the Italian Holstein Friesian Cattle Breeders Association. The hypothesis is that there are no differences among artificial insemination studs (AIS on the daughters distribution among progeny testing bulls. For each bull and beginning from 21 months of age, the distribution of daughters over the progeny testing period was calculated. Data were available on 1973 bulls born between 1986 and 2004, progeny tested in Italy and with at least 4 paternal half-sibs. On average, bulls exited the genetic centre at 11.3±1.1 months and reached their first official genetic proof at 58.0±3.1 months of age. An analysis of variance was performed on the cumulative frequency of daughters at 24, 36, 48, and 60 months. The generalized linear model included the fixed effects of year of birth of the bull (18 levels, artificial insemination stud (4 levels and sire of bull (137 levels. All effects significantly affected the variability of studied traits. Artificial insemination stud was the most important source of variation, followed by year of birth and sire of bull. Significant differences among AI studs exist, probably reflecting different strategies adopted during progeny testing.

  11. Development of a Progeny Marker for Steelhead; A Thesis submitted to Oregon State University.

    Energy Technology Data Exchange (ETDEWEB)

    Shippentower, Gene E. [Oregon State Univ., Corvallis, OR (United States)

    2009-04-15

    This study was undertaken to determine if strontium chloride could be used to create a trans-generational otolith mark in steelhead (Oncorhynchus mykiss). I completed two strontium injection trials and a survey of juvenile steelhead from various steelhead hatcheries. The two trials measured Sr:Ca ratios in otoliths in response to injections and the survey measured the natural variation in Sr:Ca ratios in otoliths of juvenile hatchery steelhead in response to the natural variation. In 2003, adult female Wallowa River, Oregon O. mykiss, were captured at the hatchery and evenly divided between a control group and two treatment groups. These females received an intraperitoneal injection of 1cc/500 g of body weight of a physiologically isotonic solution (0.9% saline) containing concentrations of 0 (control), 1000, or 5000 parts per million (ppm) of strontium chloride hexahydrate (SrCl2* 6H2O). Females were housed in a single outdoor tank until spawned artificially, and a distinct external tag identified each female within each treatment group. In 2004, female steelhead were captured throughout the duration of the adult returns to the Umatilla River basin and injected with 0, 1000, 5000, or 20,000-ppm strontium. In both trials, progeny of fish treated with strontium had significantly higher Sr:Ca ratios in the primordial region of their otoliths as measured using an electron wavelength dispersive microprobe. There was no difference in fertilization rates of eggs and survival rates of fry among treatment groups. Progeny from treated mothers were on average larger than progeny of untreated mothers. The Sr:Ca ratios in otoliths collected from various populations of steelhead were greater than the control values measured in both injections studies. This study suggests that the marking technique works and the utility for such a technique could be used for empirical observations in determining the relative fitness of progeny of adult hatchery origin fish

  12. Plate-out rates of radon progeny and particles in a spherical chamber

    International Nuclear Information System (INIS)

    Cheng, Y.S.; Chen, B.T.

    1990-01-01

    In indoor and mining environments, deposition or ''plate-out'' of radon progeny onto walls occurs simultaneously with attachment of the radon progeny to airborne particles. Attachment and plate-out processes affect the atmosphere in which radon exposures takes place by reducing concentrations and shifting activity size distributions. Both processes have important consequences in determining the deposition pattern and initial dose of inhaled radon progeny. Theoretical deposition models show that turbulence and natural convection in a room are the major factors that influence plate-out rates. Here we describe plate-out measurements for radon progeny and aerosol particles in a spherical chamber under controlled laboratory conditions. The temperature and velocity profiles in still and turbulent air were monitored. A 161-liter spherical aluminum chamber was used to study the mixing. During mixing, air velocity was detected when rotational speeds were higher than 500 rpm. Monodisperse silver aerosols and polystyrene latex particles in the size range of 5 nm to 2 μm were used in the deposition study. Radon-220 progeny were generated by passing Rn-220 gas into the chamber and letting the gas decay into 212 Pb. The deposition rates of the particles and radon progeny ( 212 Pb) in the chamber were determined by monitoring the concentration decay of the aerosol as a function of time

  13. Genetic variation in a grapevine progeny (Vitis vinifera L. cvs Grenache×Syrah) reveals inconsistencies between maintenance of daytime leaf water potential and response of transpiration rate under drought

    Science.gov (United States)

    Coupel-Ledru, Aude; Lebon, Éric; Christophe, Angélique; Doligez, Agnès; Cabrera-Bosquet, Llorenç; Péchier, Philippe; Hamard, Philippe; This, Patrice; Simonneau, Thierry

    2014-01-01

    In the face of water stress, plants evolved with different abilities to limit the decrease in leaf water potential, notably in the daytime (ΨM). So-called isohydric species efficiently maintain high ΨM, whereas anisohydric species cannot prevent ΨM from dropping as soil water deficit develops. The genetic and physiological origins of these differences in (an)isohydric behaviours remain to be clarified. This is of particular interest within species such as Vitis vinifera L. where continuous variation in the level of isohydry has been observed among cultivars. With this objective, a 2 year experiment was conducted on the pseudo-F1 progeny from a cross between the two widespread cultivars Syrah and Grenache using a phenotyping platform coupled to a controlled-environment chamber. Potted plants of all the progeny were analysed for ΨM, transpiration rate, and soil-to-leaf hydraulic conductance, under both well-watered and water deficit conditions. A high genetic variability was found for all the above traits. Four quantitative trait loci (QTLs) were detected for ΨM under water deficit conditions, and 28 other QTLs were detected for the different traits in either condition. Genetic variation in ΨM maintenance under water deficit weakly correlated with drought-induced reduction in transpiration rate in the progeny, and QTLs for both traits did not completely co-localize. This indicates that genetic variation in the control of ΨM under water deficit was not due simply to variation in transpiration sensitivity to soil drying. Possible origins of the diversity in (an)isohydric behaviours in grapevine are discussed on the basis of concurrent variations in soil-to-leaf hydraulic conductance and stomatal control of transpiration. PMID:25381432

  14. Radon and thoron progeny measurements using a portable radon sniffer

    International Nuclear Information System (INIS)

    Efendi, Z.; Jennings, P.

    1993-01-01

    A flexible version of the two-count method has been developed for use in rapid, inexpensive measurements of radon and thoron progeny working levels in residential and industrial premises in the Perth Metropolitan Area. The Method is adapted for use with a simple radon sniffer based on a low speed pump and an alpha counter. The flexibility of the method derives from the software, where some freedom is permitted in the selection of sampling times and post sampling analysis of the filters. This method has been tested on a variety of radioactive materials and it gives consistent, reliable results over a wide range of working levels. The results of a survey of Rn(222) and Rn(220) progeny levels in dwellings within the Perth Metropolitan Area are reported. This study shows that the mean concentration of indoor Rn(222) progeny was 4.7 mWL (17.4 Bq m -3 EEC) up to 23.3 mWL (86.4 Bq m -3 EEC). The mean thoron progeny concentration was 8.2 mWL (2.25 Bq m -3 EEC) with a range from 1 mWL (0.27 Bq m -3 EEC) to 64.5 mWL (17.74 Bq m -3 EEC). Using conversion factors of 0.061 mSv Bq -1 m -3 for Rn(222) progeny and 0.29 mSv Bq -1 m -3 for Rn(220) progeny respectively (UNSCEAR, 1982), it is estimated the average annual effective dose equivalent is 1.1 mSv for Rn(2220 and 0.6 mSv for Rn(220) respectively. 22 refs., 4 tabs., 1 fig

  15. Dose assessment from exposure to radon, thoron and their progeny concentrations in the dwellings of sub-mountainous region of Jammu and Kashmir, India

    International Nuclear Information System (INIS)

    Kaur, M.; Dr. B. R. Ambedkar National Institute of Technology, Jalandhar, Punjab; Kumar, A.; Mehra, R.; Mishra, R.

    2018-01-01

    The present work deals with the assessment of annual inhalation dose due to exposure of indoor radon, thoron and their progeny concentrations in the villages situated in sub-mountainous region of Jammu and Kashmir, India. The distribution of the data and the homogeneity of medians among different seasons and dwellings were assessed with the Shapiro-Wilk test and the Mann-Whitney test. The estimated total annual inhalation dose in these villages varied from 0.5 to 1.9 mSv year -1 which is less than the prescribed limit by ICRP (2008). Thus, the investigated area is safe from irradiation of radon, thoron and their progeny. (author)

  16. STUDY OF RADIATION EXPOSURE DUE TO RADON, THORON AND THEIR PROGENY IN THE INDOOR ENVIRONMENT OF RAJPUR REGION OF UTTARAKHAND HIMALAYA.

    Science.gov (United States)

    Kandari, Tushar; Aswal, Sunita; Prasad, Mukesh; Pant, Preeti; Bourai, A A; Ramola, R C

    2016-10-01

    In the present study, the measurements of indoor radon, thoron and their progeny concentrations have been carried out in the Rajpur region of Uttarakhand, Himalaya, India by using LR-115 solid-state nuclear track detector-based time-integrated techniques. The gas concentrations have been measured by single-entry pin-hole dosemeter technique, while for the progeny concentrations, deposition-based Direct Thoron and Radon Progeny Sensor technique has been used. The radiation doses due to the inhalation of radon, thoron and progeny have also been determined by using obtained concentrations of radon, thoron and their progeny in the study area. The average radon concentration varies from 75 to 123 Bq m -3 with an overall average of 89 Bq m -3 The average thoron concentration varies from 29 to 55 Bq m -3 with an overall average of 38 Bq m -3 The total annual effective dose received due to radon, thoron and their progeny varies from 2.4 to 4.1 mSv y -1 with an average of 2.9 mSv y -1 While the average equilibrium factor for radon and its progeny was found to be 0.39, for thoron and its progeny, it was 0.06. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Field investigation of surface-deposited radon progeny as a possible predictor of the airborne radon progeny dose rate.

    Science.gov (United States)

    Sun, Kainan; Steck, Daniel J; Field, R William

    2009-08-01

    The quantitative relationships between radon gas concentration, the surface-deposited activities of various radon progeny, the airborne radon progeny dose rate, and various residential environmental factors were investigated through actual field measurements in 38 selected Iowa houses occupied by either smokers or nonsmokers. Airborne dose rate was calculated from unattached and attached potential alpha energy concentrations (PAECs) using two dosimetric models with different activity-size weighting factors. These models are labeled Pdose and Jdose, respectively. Surface-deposited 218Po and 214Po were found significantly correlated to radon, unattached PAEC, and both airborne dose rates (p fireplace, or usage of a ceiling fan significantly, or marginally significantly, reduced the Pdose to 0.65 (90% CI 0.42-0.996), 0.54 (90% CI 0.28-1.02), and 0.66 (90% CI 0.45-0.96), respectively. For Jdose, only the usage of a ceiling fan significantly reduced the dose rate to 0.57 (90% CI 0.39-0.85). In smoking environments, deposited 218Po was a significant negative predictor for Pdose (RR 0.68, 90% CI 0.55-0.84) after adjusting for long-term 222Rn and environmental factors. A significant decrease of 0.72 (90% CI 0.64-0.83) in the mean Pdose was noted, after adjusting for the radon and radon progeny effects and other environmental factors, for every 10 additional cigarettes smoked in the room. A significant increase of 1.71 in the mean Pdose was found for large room size relative to small room size (90% CI 1.08-2.79) after adjusting for the radon and radon progeny effects as well as other environmental factors. Fireplace usage was found to significantly increase the mean Pdose to 1.71 (90% CI 1.20-2.45) after adjusting for other factors.

  18. Assessment of dose due to exposure to indoor radon and thoron progeny

    Directory of Open Access Journals (Sweden)

    Prasad Ganesh

    2010-01-01

    Full Text Available The components of the effective dose through inhalation from radon and its progeny are important for human health since they contribute to more than 50% of the total radiation dose from natural sources. As a consequence, radon has been identified as the second leading cause of lung cancer after smoking. Radon and its short lived decay products (218Po, 214Pb, 214Bi, 214Po present in dwellings are a radiation hazard, particularly if such sources are concentrated in the enclosed areas like poorly ventilated houses and underground mines. The indoor radon, thoron, and progeny concentrations were measured in a small hilly town of Budhakedar and the surrounding area of Tehri Garhwal, India, by using LR-115 Type II plastic track detector in a twin cup radon dosimeter. The concentrations of radon progeny were measured as the highest in winter and the lowest in summer while the thoron progeny concentration was found maximum in rainy season and minimum in autumn. The annual exposure to the potential alpha energy of radon and thoron were found to vary from 0.04 WLM to 0.69 WLM with an average value of 0.29 WLM, and 0.03 WLM to 0.37 WLM with an aver- age value of 0.16 WLM, respectively. The annual effective dose due to the exposure to indoor radon and progeny in Budhakedar homes was found to vary from 0.16 mSv to 2.72 mSv with an average value of 1.14 mSv and the effective dose due to the exposure to thoron and progeny was found to vary from 0.18 mSv to 2.49 mSv with an average value of 1.05 mSv. The results of systematic study have been obtained by considering the room as a space in which the radon and thoron levels are directly related to the dynamic and static parameters.

  19. Assessment of nanoparticle surface area by measuring unattached fraction of radon progeny

    Energy Technology Data Exchange (ETDEWEB)

    Ruzer, Lev S. [Ernest Orlando Lawrence Berkeley National Laboratory, Indoor Environment Department (United States)], E-mail: LSRuzer@lbl.gov

    2008-05-15

    A number of studies on the exposure of nanometer aerosols have indicated that health effects associated with low-solubility inhaled particles in the range of 1-100 nm may be more appropriately associated with particulate surface area than mass concentration. Such data on correlation between number, surface area and mass concentration are needed for exposure investigations, but the means for measuring aerosol surface area are not readily available. In this paper we propose a method for particle surface area assessment based on a new approach, deposition of the 'unattached fraction of radon progeny' onto nanometer aerosols.The proposed approach represents a synthesis of:(1) Derived direct analytical correlation between the 'unattached fraction' of radon progeny and surface area particle concentration in the range of 1-100 nm particle diameter;(2) Experimental data on correlation between the unattached fraction of radon progeny and particle surface area for particles with diameter in the range of 44 nm-2.1 {mu}m.

  20. Live animal measurements, carcass composition and plasma hormone and metabolite concentrations in male progeny of sires differing in genetic merit for beef production.

    Science.gov (United States)

    Clarke, A M; Drennan, M J; McGee, M; Kenny, D A; Evans, R D; Berry, D P

    2009-07-01

    In genetic improvement programmes for beef cattle, the effect of selecting for a given trait or index on other economically important traits, or their predictors, must be quantified to ensure no deleterious consequential effects go unnoticed. The objective was to compare live animal measurements, carcass composition and plasma hormone and metabolite concentrations of male progeny of sires selected on an economic index in Ireland. This beef carcass index (BCI) is expressed in euros and based on weaning weight, feed intake, carcass weight and carcass conformation and fat scores. The index is used to aid in the genetic comparison of animals for the expected profitability of their progeny at slaughter. A total of 107 progeny from beef sires of high (n = 11) or low (n = 11) genetic merit for the BCI were compared in either a bull (slaughtered at 16 months of age) or steer (slaughtered at 24 months of age) production system, following purchase after weaning (8 months of age) from commercial beef herds. Data were analysed as a 2 × 2 factorial design (two levels of genetic merit by two production systems). Progeny of high BCI sires had heavier carcasses, greater (P animal value (obtained by multiplying carcass weight by carcass value, which was based on the weight of meat in each cut by its commercial value) than progeny of low BCI sires. Regression of progeny performance on sire genetic merit was also undertaken across the entire data set. In steers, the effect of BCI on carcass meat proportion, calculated carcass value (c/kg) and animal value was positive (P carcass fat proportion (P carcass weight followed the same trends as BCI. Muscularity scores, carcass meat proportion and calculated carcass value increased, whereas scanned fat depth, carcass fat and bone proportions decreased with increasing sire EPD for conformation score. The opposite association was observed for sire EPD for fat score. Results from this study show that selection using the BCI had positive

  1. A radon progeny sampler for the determination of effective dose

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, S.B. [Australian Radiation Laboratory, Victoria (Australia)

    1997-12-01

    The design and simulated performance is described of a two-stage sampler (HE-Sampler) for {sup 222}Rn progeny. This HE-Sampler has a collection efficiency optimised to match the particle size dependency of the radon progeny dose conversion factor (DCF), derived from the latest Respiratory Tract Model of the International Commission on Radiological Protection, as implemented in the computer code RADEP. The He-Sampler comprises a wire screen pre-separator, matched to the nasal deposition, and a wire screen collector, matched to the respiratory tract collection. This HE-Sampler allows for the estimation of the radiation dose from the inhalation of {sup 222}Rn progeny, derived from two concurrent alpha particle activity measurements, one on the HE-Sampler screen collector and one on a reference filter sample. As a first approximation, the DCF is proportional to the collected fraction. The HE-Sampler response was simulated for a range of radon progeny size distributions to determine the error in the estimated DCF values. The simulation results show that the HE-Sampler is relatively insensitive to variations in sampling rate and in the screen parameters, particularly for environmental exposure. (Author).

  2. Field Investigation of the Surface-deposited Radon Progeny as a Possible Predictor of the Airborne Radon Progeny Dose Rate

    Science.gov (United States)

    Sun, Kainan; Steck, Daniel J.; Field, R. William

    2009-01-01

    The quantitative relationships between radon gas concentration, the surface-deposited activities of various radon progeny, the airborne radon progeny dose rate, and various residential environmental factors were investigated through actual field measurements in 38 selected Iowa houses occupied by either smokers or nonsmokers. Airborne dose rate was calculated from unattached and attached potential alpha energy concentrations (PAECs) using two dosimetric models with different activity-size weighting factors. These models are labeled Pdose and Jdose, respectively. Surface-deposited 218Po and 214Po were found significantly correlated to radon, unattached PAEC, and both airborne dose rates (p fireplace, or usage of a ceiling fan significantly, or marginal significantly, reduced the Pdose to 0.65 (90% CI 0.42–0.996), 0.54 (90% CI 0.28–1.02) and 0.66 (90% CI 0.45–0.96), respectively. For Jdose, only the usage of a ceiling fan significantly reduced the dose rate to 0.57 (90% CI 0.39–0.85). In smoking environments, deposited 218Po was a significant negative predictor for Pdose (RR 0.68, 90% CI 0.55–0.84) after adjusting for long-term 222Rn and environmental factors. A significant decrease of 0.72 (90% CI 0.64–0.83) in the mean Pdose was noted, after adjusting for the radon and radon progeny effects and other environmental factors, for every 10 increasing cigarettes smoked in the room. A significant increase of 1.71 in the mean Pdose was found for large room size relative to small room size (90% CI 1.08–2.79) after adjusting for the radon and radon progeny effects as well as other environmental factors. Fireplace usage was found to significantly increase the mean Pdose to 1.71 (90% CI 1.20–2.45) after adjusting for other factors. PMID:19590273

  3. Levels of thoron and progeny in high background radiation area of southeastern coast of Odisha (India))

    International Nuclear Information System (INIS)

    Ramola, R. C.; Gusain, G. S.; Rautela, B. S.; Sagar, D. V.; Prasad, G.; Shahoo, S. K.; Ishikawa, T.; Omori, Y.; Janik, M.; Sorimachi, A.; Tokonami, S.

    2012-01-01

    Exposure to radon, 222 Rn, is assumed to be the most significant source of natural radiation to human beings in most cases. It is thought that radon and its progeny are major factors that cause cancer. The presence of thoron, 220 Rn, was often neglected because it was considered that the quantity of thoron in the environment is less than that of radon. However, recent studies have shown that a high thoron concentration was found in some regions and the exposure to 220 Rn and its progeny can equal or several time exceed that of 220 Rn and its progeny. The results of thoron and its progeny measurements in the houses of high background radiation area (HBRA) of the southeastern coast of Odisha (India)) presented here. This area is one of the high background radiation areas in India with a large deposit of monazite sand which is the probable source of thoron. Both active and passive methods were employed for the measurement of thoron and its progeny in cement, brick and mud houses in the study area. Thoron concentration was measured using RAD-7 and Raduet. A CR-39 track detector was employed for the measurement of environmental thoron progeny, both in active and passive modes. Thoron and its progeny concentrations were found to be comparatively high in the area. A comparison between the results obtained with various techniques is presented in this paper. (authors)

  4. Levels of thoron and progeny in high background radiation area of southeastern coast of Odisha (India))

    Energy Technology Data Exchange (ETDEWEB)

    Ramola, R C; Gusain, G S; Rautela, B S [Dept. of Physics, H.N.B. Garhwal Univ., Badshahi Thaul Campus, Tehri Garhwal 249199 (India); Sagar, D V [Health Physics Unit EAD, BARC, IRE, OSCOM, Matikhalo, Ganjam, Odisha 761 045 (India); Prasad, G; Shahoo, S K; Ishikawa, T; Omori, Y; Janik, M [National Inst. of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba 263-8555 (Japan); Sorimachi, A; Tokonami, S [Inst. of Radiation Emergency Medicine, Hirosaki Univ., Aomori 036-8564 (Japan)

    2012-07-01

    Exposure to radon, {sup 222}Rn, is assumed to be the most significant source of natural radiation to human beings in most cases. It is thought that radon and its progeny are major factors that cause cancer. The presence of thoron, {sup 220}Rn, was often neglected because it was considered that the quantity of thoron in the environment is less than that of radon. However, recent studies have shown that a high thoron concentration was found in some regions and the exposure to {sup 220}Rn and its progeny can equal or several time exceed that of {sup 220}Rn and its progeny. The results of thoron and its progeny measurements in the houses of high background radiation area (HBRA) of the southeastern coast of Odisha (India)) presented here. This area is one of the high background radiation areas in India with a large deposit of monazite sand which is the probable source of thoron. Both active and passive methods were employed for the measurement of thoron and its progeny in cement, brick and mud houses in the study area. Thoron concentration was measured using RAD-7 and Raduet. A CR-39 track detector was employed for the measurement of environmental thoron progeny, both in active and passive modes. Thoron and its progeny concentrations were found to be comparatively high in the area. A comparison between the results obtained with various techniques is presented in this paper. (authors)

  5. Short- and long-term variability of radon progeny concentration in dwellings in the Czech Republic.

    Science.gov (United States)

    Slezáková, M; Navrátilová Rovenská, K; Tomásek, L; Holecek, J

    2013-03-01

    In this paper, repeated measurements of radon progeny concentration in dwellings in the Czech Republic are described. Two distinct data sets are available: one based on present measurements in 170 selected dwellings in the Central Bohemian Pluton with a primary measurement carried out in the 1990s and the other based on 1920 annual measurements in 960 single-family houses in the Czech Republic in 1992 and repeatedly in 1993. The analysis of variance model with random effects is applied to data to evaluate the variability of measurements. The calculated variability attributable to repeated measurements is compared with results from other countries. In epidemiological studies, ignoring the variability of measurements may lead to biased estimates of risk of lung cancer.

  6. Phytochemical profile of morphologically selected yerba-mate progenies

    Directory of Open Access Journals (Sweden)

    Alice Teresa Valduga

    2016-02-01

    Full Text Available ABSTRACT Yerba-mate (Ilex paraguariensis St. Hil is a native South American species. Plant progenies are populations that differ in terms of their productivity, morphology and phytochemical profile. This study aimed to determine the concentration of primary and secondary metabolites, such as antioxidants, in leaves, of yerba-mate progenies selected based on morphological characteristics. We evaluated the centesimal composition of secondary metabolites in the leaves of five yerba-mate plants. Methylxanthines and phenolic compounds were determined by UPLC-PDA, and antioxidant activity by measuring DPPH scavenging. Significant differences were found in centesimal composition and the contents of caffeine, theobromine, rutin and chlorogenic acid, as well as antioxidant activities, in selected progenies. The IC50 values were correlated with the chlorogenic acid levels (r2 = 0.5242 and soluble content (r2 = 0.7686. The morphological characteristics observed in yerba-mate leaves can be used as a tool for plant selection, to obtain matrices with different phytochemical profiles as a genetic material source.

  7. Effect of indoor-generated airborne particles on radon progeny dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Trassierra, C. Vargas [Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR (Italy); Stabile, L., E-mail: l.stabile@unicas.it [Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR (Italy); Cardellini, F.; Morawska, L. [National Institute of Ionizing Radiation Metrology (INMRI-ENEA), Rome (Italy); Buonanno, G. [Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, FR (Italy); International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane (Australia)

    2016-08-15

    Highlights: • Investigation of the interaction between particles and radon progeny dynamics. • Measurements of particles emitted by different indoor sources. • Tests performed in a controlled radon chamber. • Particle size strongly influences the radon progeny dynamics. • Particle surface area concentration is the key parameter of the radon-particle interaction. - Abstract: In order to investigate the interaction between radon progeny and particles, an experimental campaign was carried out in a radon chamber at the Italian National Institute of Ionizing Radiation Metrology, quantifying the amount of attached and unattached radon daughters present in air, as well as the equilibrium factor in the presence of particles generated through indoor sources. A fixed radon concentration was maintained, while particles were generated using incense sticks, mosquito coils and gas combustion. Aerosols were characterized in terms of particle concentrations and size distributions. Simultaneously, radon concentration and attached/unattached potential alpha energy concentration in the air were continuously monitored by two different devices, based on alpha spectroscopy techniques. The presence of particles was found to affect the attached fraction of radon decay products, in such a way that the particles acted as a sink for radionuclides. In terms of sources which emit large particles (e.g. incense, mosquito coils), which greatly increase particle surface area concentrations, the Equilibrium Factor was found to double with respect to the background level before particle generation sessions. On the contrary, the radon decay product dynamics were not influenced by gas combustion processes, mainly due to the small surface area of the particles emitted.

  8. Risk of lung cancer in animals following low exposures to Radon-222 progeny

    International Nuclear Information System (INIS)

    Duport, P.; Monchaux, G.; Morlier, J.P.

    1997-01-01

    Owing to the facts that a) large uncertainties affect the epidemiology of radon progeny-induced lung cancer in humans (especially at low exposures), and b) the rat is a good model for studying the carcinogenicity of radon progeny in humans, the risk of lung cancer following low exposures to low concentrations of radon progeny can be estimated from data obtained in the laboratory on rats exposed under controlled conditions. From the limited set of laboratory data on the induction of lung cancer in laboratory rats it appears that, at low exposures, the risk of lung cancer decreases with decreasing concentration, and that exposures of the order of 25 WLM, at an exposure rate of 2 WL do not produce any excess lung cancers. Since 20 WLM is a lifetime exposure comparable to those expected in occupational or indoors conditions and 2 WL is an exposure rate about 20 times higher dm current occupational exposures rates and 100 times higher than indoor ones, these observations may be indicative of threshold conditions for the induction of lung cancer by radon progeny. (author)

  9. Variability of silver fir (Abies alba Mill. progeny from the Tisovik Reserve expressed in needle traits and chloroplast microsatellite DNA

    Directory of Open Access Journals (Sweden)

    Pawlaczyk Ewa M.

    2017-01-01

    Full Text Available Progeny from nineteen family lines of silver fir (Abies alba Mill. from the Tisovik Reserve growing in an experimental plot were analyzed based on 4 chloroplast microsatellite DNA loci and 12 morphological and anatomical needle traits. The Tisovik Reserve is located in Białowieża Primeval Forest, 120 km north of the natural range limit of this species, and embraces a small and isolated natural population of silver fir. The aim of this study was to determine genetic variation within and between progeny lines. Analysis of phenotypic variation showed that the traits which differed most among individuals were the needle width and the distance from resin canals to vascular bundle. Those traits, which differed most between the progeny lines, were the number of endodermic cells around the vascular bund and the weight of hypodermic cells. In Tisovik progeny, we detected 107 different haplotypes. In progeny lines, we detected more haplotypes than in maternal trees, and most haplotypes did not exist in maternal trees. This may be the result of pollen influx from other silver fir stands. Progeny from Tisovik showed a higher level of variability in comparison with maternal trees.

  10. Genetic variation in dieback resistance in Fraxinus excelsior confirmed by progeny inoculation assay

    DEFF Research Database (Denmark)

    Lobo, Albin; McKinney, Lea Vig; Hansen, Jon Kehlet

    2015-01-01

    from low susceptible mother clones developed smaller necroses when compared to offspring from susceptible clones. Their crown damage due to natural infections was also significantly less. The correlation coefficient between average crown damages of mother clones and the average of their progeny was 0...

  11. Study on radon and thoron progeny levels in Gudalore in South India

    International Nuclear Information System (INIS)

    Selvasekarapandian, S.; Sivakumar, R.; Mugunthamanikandan, N.; Meenakshisundaram, V.; Santhanam, R.

    2000-01-01

    One of the important route of radiation exposure to man is through inhalation of air containing radioisotopes. A major contribution to inhalation dose comes from radon, thoron and its progenies. The indoor radon and thoron progeny levels are determined by two count method. In this method the radon and thoron progenies are collected on a glass fiber filter paper using volume air sampler (Staplex) and counted for alpha activity in ZnS (Ag) alpha counting system. It is observed that thoron working level is higher than the radon working level in all houses except few houses with stone walls and mosaic floor. Behavior of indoor radon and thoron working levels for different seasons at different houses are determined and discussed in detail. Radon and thoron working levels are measured high in winter, autumn, and low in summer and rainy seasons. Among all seasons highest value is measured in winter and low in summer and rainy seasons. Radon progeny working level varies from 1.659 to 6.675 mWL, whereas thoron progeny working level varies from 1.670 to 12.671 mWL. The geometric mean values of radon and thoron progeny concentration in the present study are 2.836 and 4.133 mWL. The high thoron progeny level observed in this is attributed to the high thorium content observed in soils of this area. (author)

  12. Indoor radon and its progeny levels in new type houses in rural area of Hubei

    International Nuclear Information System (INIS)

    He Quan; Xiong Zhaoxing; He Zuan; Zheng Youqing

    1993-01-01

    Using Cluster Sampling method, indoor radon of 54 rooms and radon progeny potential alpha-energy concentrations of 200 rooms were measured in the new type brick-concrete 2-storey flats and old type brick-wood single-storey residences in the rural area. Instant and cumulative samplings and measurements were made. The average per capita residential area of the surveyed houses was 28.1 m 2 , clear height 3.6 m. The geometric means of indoor radon concentration were 18.22 Bq.m -3 and 15.93 Bq.m -3 for storied and single-storey buildings, respectively; radon progeny potential alpha-energy concentrations were 2.62 mWL and 2.54 mWL, correspondingly. In storied buildings, the arithmetic mean of indoor cumulative radon concentration was 25.56 Bq.m -3 in summer, and 37.94 Bq.m -3 in winter. The annual effective dose equivalent of radon progeny inhaled indoors and outdoors was 0.80 mSv. (orig.). (6 refs., 1 fig., 5 tabs.)

  13. A nationwide survey of radon concentration in Japan. Indoor, outdoor and workplace

    International Nuclear Information System (INIS)

    Sanada, Tetsuya; Oikawa, Shinji; Kanno, Nobuyuki; Abukawa, Johji; Higuchi, Hideo

    2004-01-01

    The nationwide indoor, outdoor and workplace radon concentrations were surveyed in Japan. These surveys were conducted to estimate the natural radiation dose due to radon and its progeny for the general public. The radon concentration was measured using passive type radon monitor. The number of radon monitors were installed at indoor, outdoor and workplace for 940 houses, 705 points and 705 sites, respectively. The radon concentration was measured for one year at each measurement site. Annual mean radon concentration was obtained from four quarters measurements of 47 prefectures in Japan. The nationwide indoor, outdoor and workplace annual mean radon concentration were 15.5 Bq m -3 , 6.1 Bq m -3 and 20.8 Bq m -3 , respectively. Their radon concentration shows approximately a logarithmic normal distribution. Workplace showed relatively high radon concentration compared with other environments, may be due to construction materials and low ventilation rate. The indoor radon concentration found to be seasonal variation and architectural dependences. Seasonal variation and regional distribution of outdoor radon concentration was also observed. From the results of these radon surveys, the annual effective dose to the general public due to radon and its progeny was estimated to be 0.49 mSv y -1 in Japan. (author)

  14. A method for determining an indicator of effective dose calculation due to inhalation of Radon and its progeny from in vivo measurements

    International Nuclear Information System (INIS)

    Estrada, Julio Jose da Silva

    1994-01-01

    Direct measurement of the absolved dose to lung tissue from inhalation of radon and its progeny is not possible and must be calculated using dosimetric models, taking into consideration the several parameters upon which the dose calculation depends. To asses the dose due to inhalation of radon and its progeny, it is necessary to estimate the cumulative exposure. Historically, this has been done using WLM values estimated with measurements of radon concentration in air. The radon concentration in air varies significantly, however, in space with time, and the exposed individual is also constantly moving around. This makes it almost impossible to obtain a precise estimate of an individual's inhalation exposure. This work describes a pilot study to calculate lung dose from the deposition of radon progeny, via estimates of cumulative exposure derived from in vivo measurements of 210 Pb, in subjects exposed to above-average radon and its progeny concentrations in their home environments. The measurements were performed in a whole body counter. With this technique, the exposed individuals become, in affect, their own samplers and dosimeters and the estimate of cumulative exposure is not affected by the variation of the atmospheric concentration of radon and its progeny in time and space. Forty individuals identified as living in homes with radon levels ranging from about 740 Bq/m 3 to 150.000 Bq/m 3 were measured. Also, additional 34 measurements were made on personnel from NYUMC/NIEM who live in a residential area surrounding the laboratory in which the levels of radon have been shown to be at below average values. To realize these measurements a methodology was developed to determine the subject's background, using a head phantom made with a cubic plastic container containing known amounts of potassium and calcium dissolved in four liters of water. The effective doses calculated from the in vivo measurements are compared to effective doses estimated, for the same

  15. A radon progeny deposition model

    International Nuclear Information System (INIS)

    Rielage, Keith; Elliott, Steven R.; Hime, Andrew; Guiseppe, Vincent E.; Westerdale, S.

    2010-01-01

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly 222 Rn) and its subsequent progeny present in an experiment are potential backgrounds, also problematic is the deposition of radon progeny on detector materials. Exposure to radon at any stage of assembly of an experiment can result in surface contamination by progeny supported by the long half life (22 y) of 210 Pb on sensitive locations of a detector. An understanding of the potential surface contamination from deposition will enable requirements of radon-reduced air and clean room environments for the assembly of low background experiments. It is known that there are a number of environmental factors that govern the deposition of progeny onto surfaces. However, existing models have not explored the impact of some environmental factors important for low background experiments. A test stand has been constructed to deposit radon progeny on various surfaces under a controlled environment in order to develop a deposition model. Results from this test stand and the resulting deposition model are presented.

  16. A Radon Progeny Deposition Model

    International Nuclear Information System (INIS)

    Guiseppe, V. E.; Elliott, S. R.; Hime, A.; Rielage, K.; Westerdale, S.

    2011-01-01

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly 222 Rn) and its subsequent progeny present in an experiment are potential backgrounds, also problematic is the deposition of radon progeny on detector materials. Exposure to radon at any stage of assembly of an experiment can result in surface contamination by progeny supported by the long half life (22 y) of 210 Pb on sensitive locations of a detector. An understanding of the potential surface contamination from deposition will enable requirements of radon-reduced air and clean room environments for the assembly of low background experiments. It is known that there are a number of environmental factors that govern the deposition of progeny onto surfaces. However, existing models have not explored the impact of some environmental factors important for low background experiments. A test stand has been constructed to deposit radon progeny on various surfaces under a controlled environment in order to develop a deposition model. Results from this test stand and the resulting deposition model are presented.

  17. Frequency of Aneuploids in Progenies of Autotriploid Barley, Hordeum Vulgare L

    DEFF Research Database (Denmark)

    Sandfær, J.

    1979-01-01

    Chromosome counts of 863 progeny plants originating from 68 autotriploid barley plants revealed a considerable variation in chromosome numbers ranging from the diploid number (2n= 14) to 2n= 39. The most frequent groups were plants with 15 and 16 chromosomes each constituting about 27% of all pro...

  18. Maternal Exposure to Cadmium and Manganese Impairs Reproduction and Progeny Fitness in the Sea Urchin Paracentrotus lividus.

    Directory of Open Access Journals (Sweden)

    Oriana Migliaccio

    Full Text Available Metal contamination represents one of the major sources of pollution in marine environments. In this study we investigated the short-term effects of ecologically relevant cadmium and manganese concentrations (10(-6 and 3.6 x 10(-5 M, respectively on females of the sea urchin Paracentrotus lividus and their progeny, reared in the absence or presence of the metal. Cadmium is a well-known heavy metal, whereas manganese represents a potential emerging contaminant, resulting from an increased production of manganese-containing compounds. The effects of these agents were examined on both P. lividus adults and their offspring following reproductive state, morphology of embryos, nitric oxide (NO production and differential gene expression. Here, we demonstrated that both metals differentially impaired the fertilization processes of the treated female sea urchins, causing modifications in the reproductive state and also affecting NO production in the ovaries. A detailed analysis of the progeny showed a high percentage of abnormal embryos, associated to an increase in the endogenous NO levels and variations in the transcriptional expression of several genes involved in stress response, skeletogenesis, detoxification, multi drug efflux processes and NO production. Moreover, we found significant differences in the progeny from females exposed to metals and reared in metal-containing sea water compared to embryos reared in non-contaminated sea water. Overall, these results greatly expanded previous studies on the toxic effects of metals on P. lividus and provided new insights into the molecular events induced in the progeny of sea urchins exposed to metals.

  19. An Alpha spectrometer for measuring radon daughter individual activity concentration; Spettrometro Alfa per la misura delle concentrazioni individuali in attivita' della progenie del radon

    Energy Technology Data Exchange (ETDEWEB)

    Berico, M.; Formignani, M. [ENEA, Div. Protezione dell' Uomo e degli Ecosistemi, Centro Ricerche E. Clementel, Bologna (Italy); Mariotti, F. [Bologna Univ., Bologna (Italy). Dipt. di Fisica

    2001-07-01

    In the frame of the program of the Institute for Radiation Protection of ENEA, related to the evaluation of dose from radon and thoron progeny, an alpha spectrometer for the continuous air monitoring (CAM type) of radon and thoron has been realized. The constructive characteristics of the device are here presented together with energy and efficiency calibration. The device allows, by means of a screen type diffusion battery and a filter, to determinate the single radioactivity of each radionuclide of the progeny selecting them in relation to their diffusive behaviour (dichotomous particle size selection). The three-count filter method has been employed to measure the concentrations of {sup 218}Po, {sup 214}Pb and {sup 214}Bi in air. Radon and thoron effective doses using a dosimetric, instead of an epidemiologic approach, will be then evaluated. [Italian] Presso l'Istituto per la Radioprotezione, nell'ambito del programma di valutazione di dose da radon e' stato progettato e realizzato uno spettrometro alfa per il monitoraggio continuo in aria (CAM) della progenie del radon e del toron. Le caratteristiche costruttive dello strumento permettono, tramite l'utilizzo di batterie a diffusione a reti, di determinare l'attivita' individuale della progenie per diverse dimensioni granulometriche in particolare per la frazione attaccata e non al particolato amosferico con un taglio granulometrico di qualche nanometro. E' stato inoltre applicato un metodo spettrometrico a tre conteggi per il calcolo delle concentrazioni individuali della progenie del radon, {sup 218}Po, {sup 214}Pb and {sup 214}Bi, effettuando un conteggio alfa di {sup 218}Po e due conteggi alfa di {sup 214}Po. Tale informazione consentira' una valutazione della dose di radon utilizzando il modello dosimetrico in alternativa a quello epidemiologico.

  20. Comparative study on immunoglobulin Y transfer from breeding hens to egg yolk and progeny chicks in different breeds of poultry

    Directory of Open Access Journals (Sweden)

    Ritu Agrawal

    2016-04-01

    Full Text Available Aim: This study was undertaken to compare the immunoglobulin Y (IgY level and its efficacy in laying hens of four different breeds of poultry (viz.,Vanraja, Gramapriya, BlackRock, and KalingaBrown and its relative transfer in egg yolk and chick. Materials and Methods: This study was conducted in 48 apparently healthy laying hens vaccinated with Salmonella inactivated polyvalent vaccine, eggs and progeny chicks; 12 each from four different breeds of poultry,viz.,Vanraja, Gramapriya, BlackRock, and KalingaBrown. The methodology included measurement of egg and yolk weight, total protein and IgY in egg yolk, total serum protein and IgY in breeding hens, and progeny chicks and extent of IgY transfer from hens to yolk then to chicks. Further, Salmonella-specific antibodies in breeding hens, egg yolk and progeny chicks were assessed using O and H antigen by tube agglutination test. Results: The egg weight differed nonsignificantly (p>0.05 among breeds, however, breed wise significant variation (p0.05 difference among breed was found in total protein of egg yolk and chick. The IgY concentration in hens, egg yolk and chick was found to be in the range of 5.35±0.63- 5.83±0.65, 2.3±0.1-2.6±0.2, and 1.3±0.11-1.7±0.16 mg/ml, respectively which is uniform and independent of total protein concentration at all the three levels. Significant breed variations were not observed in maternal IgY transfer from breeding hens to chicks and were 25.62±1.42-36.06±4.34% of total IgY in parent flock. Moderate to higher rate of seroprevalence with peak titers of 1:640 against Salmonella-specific antibodies was observed in only 41.6% of breeding hens. Conclusion: No significant difference in the rate of transfer of IgY was observed in four breeds studied (viz.,Vanraja, Gramapriya, BlackRock, and KalingaBrown and moderate seropositivity was detected for Salmonella-specific antibodies in progeny chicks.

  1. Nickel sulfate induces numerous defects in Caenorhabditis elegans that can also be transferred to progeny

    International Nuclear Information System (INIS)

    Wang Dayong; Wang Yang

    2008-01-01

    Whether the multiple biological toxicities from nickel exposure could be transferred to progeny has not been clarified. In this report, we explored the Caenorhabditis elegans to analyze the multiple toxicities of nickel and their possibly transferable properties. The nickel toxicity caused multiple biological defects in a concentration-dependent manner. Moreover, most of these toxicities could be transferred and could be only partially rescued in progeny. Some specific phenotypes in progeny were also found to exhibit no obvious rescue phenotypes or to show even more severe defects than their parents. The defects caused by nickel exposure could be classified into four groups according to their transferring properties. That is, the defects caused by nickel exposure could be largely, or partially, or unable to be rescued, or became even more severe in progeny animals. Therefore, most of the nickel exposure-caused defects can be transferred from parents to their progeny to different degrees in C. elegans. - Nickel exposure can cause multi-biological toxicities and these defects can be transferred from parents to their progeny in C. elegans

  2. Nickel sulfate induces numerous defects in Caenorhabditis elegans that can also be transferred to progeny

    Energy Technology Data Exchange (ETDEWEB)

    Wang Dayong [Department of Genetics and Developmental Biology, Southeast University, Nanjing 210009 (China); Key Laboratory of Developmental Genes and Human Disease, Ministry of Education (China)], E-mail: dayongw@seu.edu.cn; Wang Yang [Department of Genetics and Developmental Biology, Southeast University, Nanjing 210009 (China); Key Laboratory of Developmental Genes and Human Disease, Ministry of Education (China)

    2008-02-15

    Whether the multiple biological toxicities from nickel exposure could be transferred to progeny has not been clarified. In this report, we explored the Caenorhabditis elegans to analyze the multiple toxicities of nickel and their possibly transferable properties. The nickel toxicity caused multiple biological defects in a concentration-dependent manner. Moreover, most of these toxicities could be transferred and could be only partially rescued in progeny. Some specific phenotypes in progeny were also found to exhibit no obvious rescue phenotypes or to show even more severe defects than their parents. The defects caused by nickel exposure could be classified into four groups according to their transferring properties. That is, the defects caused by nickel exposure could be largely, or partially, or unable to be rescued, or became even more severe in progeny animals. Therefore, most of the nickel exposure-caused defects can be transferred from parents to their progeny to different degrees in C. elegans. - Nickel exposure can cause multi-biological toxicities and these defects can be transferred from parents to their progeny in C. elegans.

  3. Portable monitors for measuring radon and its progenies air by intergrated sampling method

    International Nuclear Information System (INIS)

    Zhang Huaiqin; Su Jingling; Yao Wanyuan; Liu Jinhua

    1989-01-01

    Two kinds of portable monitors have been developed, which can be used to measure the concentration of radon or potential energy concentration of radon or potential energy concentration of radon progenies in air. The thermoluminescent material CaSO 4 (Tm) is used as a detecting element for both of them. The lowest detectable limit of the passive radon monitor is about 1.5 Bq/m 3 for radon in air, as the exposure time being one week. Its main advantages are high reliability and convenient manipulation. The working level monitor for radon progenies in air consists of a mini membrane pump and an integrating probe. The lowest detectable limit is about 6.2 x 10 -9 J/m 3 , as the sampling time being 6 hours. It weights only about 0.35 kg

  4. Dose-dependent in vivo cell-cycle changes following radon progeny exposure

    International Nuclear Information System (INIS)

    Johnson, N.F.; Carpenter, T.R.; Hickman, A.W.; Jaramillo, R.J.; Gurule, D.M.

    1994-01-01

    Exposures to low concentrations of alpha-emitting radon progeny are reported by the U.S. Environmental Protection Agency to be the second leading cause of lung cancer. Current risk estimates for lung cancer from the inhalation of radon progeny are based on data from underground uranium miners. To produce such risk estimates, calculations are based on several assumptions concerning exposure-response relationships rather than dose-response relationships. A better understanding of the mechanisms of interactions between alpha particles, the cells of the respiratory tract, and the progression toward cancer may validate the mathematical models used to derive risk estimates

  5. Levels of radon gas concentration and progeny in homes of Potosi City, Bolivia to 4000 m; Niveles de concentracion de gas radon y progenie en viviendas de la Ciudad de Potosi, Bolivia a 4000 msnm

    Energy Technology Data Exchange (ETDEWEB)

    Mamani M, R. [Universidad Autonoma Tomas Frias, Carrera de Fisica, Av. del maestro s/n, Edif. Central Potosi, Villa Imperial de Potosi (Bolivia, Plurinational State of); Claros J, J. [Universidad Autonoma Tomas Frias, Facultad de Minas Potosi, Centro de Investigacion, Av. Serrudo y Arce s/n, Villa Imperial de Potosi (Bolivia, Plurinational State of); Vasquez A, R., E-mail: raulm2k13@hotmail.com [Instituto Boliviano de Biologia de Altura, Calle Hoyos 953, La Paz (Bolivia, Plurinational State of)

    2015-10-15

    Full text: In this work the presence of radon gas was determined, which is a radioactive contaminant that comes from underground, able to penetrate the houses. The danger is that when mixed air and when inhaled can cause serious damage to the lungs, for the short life time that has radon and progeny for decay, damaging the pulmonary alveoli and reducing breathing capacity of the habitants, then causing polycythemia in some cases. The study was carried out in homes in the city of Potosi, Bolivia located at 4000 m. The quantification of radon gas and progeny was performed with the equipment Alpha-Zaeller-2 (Az-2), quantification was realized in 6 zones of the city of Potosi, chosen randomly. In each zone were carried out measurements in 40 homes (2 rooms more permanent), both day and night, for a period of 3 days in two different seasons and with concentrations of average humidity of 20, 50 and 80%. The values obtained for each period vary depending on the season and 30 to 50% of the allowable values given by the EPA and Who for housing. (Author)

  6. Intercomparison of active, passive and continuous instruments for radon and radon progeny measurements in the EML chamber and test facility

    International Nuclear Information System (INIS)

    George, A.C.; Knutson, E.O.; Tu, K.W.; Fisenne, I.M.

    1995-12-01

    The results from the May 1995 Intercomparison of Active, Passive and Continuous Instruments for Radon and Radon Progeny Measurement conducted in the EML radon exposure and test facility are presented. Represented were 13 participants that measure radon with open faced and diffusion barrier activated carbon collectors, 10 with nuclear alpha track detectors, 9 with short-term and long-term electret/ionization chambers, and 13 with active and passive commercial electronic continuous monitors. For radon progeny, there were four participants that came in person to take part in the grab sampling methodology for measuring individual radon progeny and the potential alpha energy concentration (PAEC). There were 11 participants with continuous and integrating commercial electronic instruments that are used for measuring the PAEC. The results indicate that all the tested instruments that measure radon fulfill their intended purpose. All instruments and methods used for grab sampling for radon progeny did very well. However, most of the continuous and integrating electronic instruments used for measuring the PAEC or working level appear to underestimate the potential risk from radon progeny when the concentration of particles onto which the radon progeny are attached is -3

  7. External gamma exposure to radon progeny in indoor air

    International Nuclear Information System (INIS)

    Fujimoto, Kenzo

    1985-01-01

    The external γ-exposure from radon progeny uniformly distributed in indoor air was estimated by a computer program that was developed. This program can calculate the fluence rate, exposure rate and average energy for any given point in a room of any given size. As numerical example, the exposure rate normalized to unit airborne activity is presented, together with the fluence-weighted and exposure-weighted average photon energies, for a room of representative geometry containing radon progeny in equilibrium. To cover other conditions encountered in practice, quantitative evaluations are additionally presented of the effect on the exposure brought by changes in certain parameters, such as equilibrium factor, wall thickness, room size and receptor position. The study has quantitatively substantiated the prevailing postulate that the effective dose equivalent due to external exposure resulting from normal indoor concentrations of airborne radon progeny in the room of representative geometry should only amount to 0.04 % of that from the internal exposure from the same sources, and that it should be of similarly negligible order compared with internal exposure also in the case of other room geometries. (author)

  8. Association of Increased Grain Iron and Zinc Concentrations with Agro-morphological Traits of Biofortified Rice

    Directory of Open Access Journals (Sweden)

    Laura Tatiana Moreno-Moyano

    2016-09-01

    Full Text Available Biofortification of rice (Oryza sativa L. with micronutrients is widely recognized as a sustainable strategy to alleviate human iron (Fe and zinc (Zn deficiencies in developing countries where rice is the staple food. Constitutive overexpression of the rice nicotianamine synthase (OsNAS genes has been successfully implemented to increase Fe and Zn concentrations in unpolished and polished rice grain. Intensive research is now needed to couple this high-micronutrient trait with high grain yields. We investigated associations of increased grain Fe and Zn concentrations with agro-morphological traits of backcross twice second filial (BC2F2 transgenic progeny carrying OsNAS1 or OsNAS2 overexpression constructs under indica/japonica and japonica/japonica genetic backgrounds. Thirteen agro-morphological traits were evaluated in BC2F2 transgenic progeny grown under hydroponic conditions. Concentrations of 8 mineral nutrients (Fe, Zn, copper, manganese, calcium, magnesium, potassium and phosphorus in roots, stems/sheaths, non-flag leaves, flag leaves, panicles and grain were also determined. A distance-based linear model (DistLM was utilized to extract plant tissue nutrient predictors accounting for the largest variation in agro-morphological traits differing between transgenic and non-transgenic progeny. Overall, the BC2F2 transgenic progeny contained up to 148% higher Fe and 336% higher Zn concentrations in unpolished grain compared to non-transgenic progeny. However, unpolished grain concentrations surpassing 23 µg Fe g-1 and 40 µg Zn g-1 in BC2F2 indica/japonica progeny, and 36 µg Fe g-1 and 56 µg Zn g1 in BC2F2 japonica/japonica progeny, were associated with significant reductions in grain yield. DistLM analyses identified grain-Zn and panicle-magnesium as the primary nutrient predictors associated with grain yield reductions in the indica/japonica and japonica/japonica progeny, respectively. We subsequently produced polished grain from high

  9. Seasonal variation of radon concentrations in UK homes

    International Nuclear Information System (INIS)

    Miles, J C H; Howarth, C B; Hunter, N

    2012-01-01

    The patterns of seasonal variation of radon concentrations were measured in 91 homes in five regions of the UK over a period of two years. The results showed that there was no significant difference between the regions in the pattern or magnitude of seasonal variation in radon concentrations. The arithmetic mean variation was found to be close to that found previously in the UK national survey. Differences in the pattern between the two years of the study were not significant. Two-thirds of homes in the study followed the expected pattern of high radon in the winter and low radon in the summer. Most of the rest showed little seasonal variation, and a few showed a reversed seasonal pattern. The study does not provide any clear evidence for the recorded house characteristics having an effect on the seasonal variation in radon concentrations in UK homes, though the statistical power for determining such effects is limited in this study. The magnitude of the seasonal variation varied widely between homes. Analysis of the individual results from the homes showed that because of the wide variation in the amount of seasonal variation, applying seasonal correction factors to the results of three-month measurements can yield only relatively small improvements in the accuracy of estimates of annual mean concentrations.

  10. Health effects of inhaled radon progeny

    International Nuclear Information System (INIS)

    Monchaux, G.

    1997-01-01

    The relationship between an increased risk of lung cancer and exposure to radon progeny has been studied in eleven cohorts of underground workers, both in uranium and non uranium mines as well as in experimental animals. Risk estimates derived from miners studies are used to assess the risk of lung cancer in relation to exposure to indoor radon progeny. Human and animal experimental data are reviewed in the perspective of risk assessment for low exposure to radon progeny, in the conditions of the contemporary working environment as well as the indoor domestic environment. (authors)

  11. Exposures to 222Rn and its progeny derived from implanted 210Po activity

    International Nuclear Information System (INIS)

    Nikezic, D.; Yu, K.N.

    2006-01-01

    The Jacobi room model was applied to study the relative contributions from the unattached and attached fractions to the implanted activity of 210 Po. It was found that under normal conditions, about 85% of the implantation was due to the unattached fraction. Sensitivity analysis was performed to identify the most important factors that influence the deposition and implantation of radon progeny. The main factors affecting the incorporation of 210 Po are the attachment rate, deposition rate of unattached progeny and the surface to volume ratio of the room. The calibration curves, which related the 210 Po activity per unit surface area to the concentrations of 222 Rn and of the radon progeny, were determined as functions of exposure times. The implanted activity is found to distribute close to a lognormal distribution. For an exposure of 20 years, the distribution has a geometric standard deviation of 2.2 and a geometric mean of 0.023Bq/m 2 /(Bq/m 3 ). The last value is considered as the calibration coefficient of the glass response in terms of the implanted 210 Po activity per unit surface area per unit concentration of 222 Rn for an exposure period of 20 years

  12. Particle size distribution of the radon progeny and ambient aerosols in the Underground Tourist Route "Liczyrzepa" Mine in Kowary Adit

    Science.gov (United States)

    Wołoszczuk, Katarzyna; Skubacz, Krystian

    2018-01-01

    Central Laboratory for Radiological Protection, in cooperation with Central Mining Institute performed measurements of radon concentration in air, potential alpha energy concentration (PAEC), particle size distribution of the radon progeny and ambient aerosols in the Underground Tourist-Educational Route "Liczyrzepa" Mine in Kowary Adit. A research study was developed to investigate the appropriate dose conversion factors for short-lived radon progeny. The particle size distribution of radon progeny was determined using Radon Progeny Particle Size Spectrometer (RPPSS). The device allows to receive the distribution of PAEC in the particle size range from 0.6 nm to 2494 nm, based on their activity measured on 8 stages composed of impaction plates or diffusion screens. The measurements of the ambient airborne particle size distribution were performed in the range from a few nanometres to about 20 micrometres using Aerodynamic Particle Sizer (APS) spectrometer and the Scanning Mobility Particle Sizer Spectrometer (SMPS).

  13. Seasonal variations of indoor radon concentrations

    International Nuclear Information System (INIS)

    Majborn, B.

    1990-01-01

    Seasonal variations of indoor radon concentrations have been studied in a cluster of 10 single-family houses. Eight of the houses are of a similar construction with slab-on-grade foundations. The remaining two houses have different substructures, one of them having a crawl space, and the other having partly a basement and partly a crawl space. A 'normal' seasonal variation of the radon concentration with a maximum in winter and a minimum in summer was observed in most of the houses. In these houses the variation showed a strong correlation with the indoor-outdoor temperature difference on a 2-month basis. However, deviating seasonal variations were observed in some of the houses, notably in the two houses having different substructures. This paper reports that a re-examination of the data obtained in a previous study indicates that winter/summer ratios of indoor radon concentrations in Danish houses depend on the house substructure. The mean winter/summer ratios were about 2.1 for houses with slab-on-grade foundations, 1.5 for houses having a basement, and 1.0 for houses with a crawl space (geometric mean values). However, a study with more houses in each substructure category will be needed to show whether or not the indicated differences are generally valid for Danish houses

  14. A study of radon variation in dwelling during 1988

    International Nuclear Information System (INIS)

    Shaikh, A.N.; Ramachandran, T.V.; Muraleedharan, T.S.; Subbaramu, M.C.

    1989-01-01

    Natural radioactivity due to radon and its progeny levels indoors contributes significantly to the total radiation to man. The main source of radon and its progeny in a dwelling is the emanation of radon gas from soil. The temperature and ventilation vary in a dwelling during the year. These parameters influence the indoor radon levels. The seasonal variation of radon was studied in a dwelling as well as in the outside air. The filter paper method and alpha counting, and the solid state track detector technique and track counting were used to study the radon levels. The geometric mean of radon daughters concentrations were 0.5 mWL and 0.8 mWL measured by filter-paper method and SSNTD method respectively. The geometric mean of radon concentrations were 6.2 Bqm -3 and 10.0 Bqm -3 by filter-paper method and SSNTD method respectively. (author). 3 figs., 3 tabs., 13 refs

  15. Measurements of radon progeny activity on typical indoor surfaces

    International Nuclear Information System (INIS)

    Knutson, E.O.; Gogolak, C.V.; Klemic, G.

    1992-01-01

    A number of studies aimed at defining how well radon progeny on surfaces can be measured, information that is needed in order to test physical/mathematical models governing indoor radon progeny behaviour, are described. One experiment compared the decomposition on to different surfaces. Only relatively small differences were found among metal, filter paper, broadcloth, corduroy fabric, vinyl wallpaper, glass, and latex paint, but polyethylene film collected two to four times as much as the others, due most likely to electrostatic charge on the plastic surface. Another experiment compared the gamma and gross alpha count methods of measuring surface activity for metal, filter paper, broadcloth and corduroy surfaces. No difference for the surfaces tested was found from which it is concluded that, even for rougher surfaces, progeny atoms deposit mainly on the outer layers. A final experiment compared in situ and surrogate-surface methods for measuring surface deposition. For most tests, the two methods agreed within 30%, and the average ratio was not significantly different from unity. 210 Po is a complication in the in situ method. An unexpected location effect was found in the experiments conducted in houses with high radon concentrations: the deposition on the ceiling was higher than on the surfaces. (author)

  16. Genetic parameters on Bali cattle progeny test population

    Science.gov (United States)

    Hariansyah, A. R.; Raharjo, A.; Zainuri, A.; Parwoto, Y.; Prasetiyo, D.; Prastowo, S.; Widyas, N.

    2018-03-01

    Bali cattle (Bos javanicus) is Indonesian indigenous cattle with having superior genetics potential on fitness traits in tropical environment and low feed quality. Bali Cattle Breeding Center Pulukan Indonesia conducted progeny test per annum in order to select bulls using offspring’s phenotype. This paper aimed to estimate the genetic parameters of yearling weight in Bali cattle progeny test populations and to observe the variation between periods in the above breeding center. Data were collected from the year of 2013 to 2014. There were four bulls (3 tests, 1 AI control) in 2013 and five bulls (4 tests, 1 AI) in 2014. Thirty breeding females were allocated per paddock per bull and allowed to mate naturally. In total 80 and 104 offspring’s records were obtained from 2013 and 2014 data, respectively. We built half-sib family model to estimate the additive genetic variance due to the sire and later estimate the breeding value (EBV) of each sire. Results showed that in 2013 the heritability (h2) for yearling weight was 0.19 while in 2014 was 0.79. In both years, tested bulls had higher EBV compared to the control bulls. The remarkable difference of heritability between years was due to the variations among bull candidates which might differ every year with regards to their origins. The fact that the EBV of tested bulls were higher than the control bulls gave us insight that despite the conservation policy and the continuous departure of Bali cattle bulls outside the Island, the population could still maintain its genetic quality.

  17. AGE-DEPENDENT INHALATION DOSE DUE TO EXPOSURE OF SHORT LIVED PROGENY OF RADON AND THORON FOR DIFFERENT AGE GROUPS IN JAMMU & KASHMIR, HIMALAYAS.

    Science.gov (United States)

    Sharma, Sumit; Kumar, Ajay; Mehra, Rohit

    2018-05-16

    Dosimetric approach is used in this study for the assessment of doses due to inhalation of short lived radon/thoron progeny to the inhabitants of Udhampur district of Jammu & Kashmir. This paper also presents the activity concentrations and unattached fraction of radon and thoron progeny. The observed annual concentration of attached and unattached 222Rn and 220Rn progeny has been found to vary from 8 to 32 and 0.09 to 14 Bq/m3, 0.75 to 3.16 and 0.01 to 1.13 Bq/m3, respectively. The inhalation doses from radon progeny to different body organs of different age groups have been calculated by using the age dependent biokinetic model. The attachment rate of 222Rn and indoor aerosol concentration of 222Rn and 220Rn have been estimated and their relation between them has also been studied. The dose conversion factor for mouth and nasal breathing to different exposure conditions has been obtained from Porstendorfer model.

  18. Study of radiation exposure due to radon, thoron and progeny in the indoor environment of Yamuna and Tons valleys of Garhwal Himalaya

    International Nuclear Information System (INIS)

    Prasad, Mukesh; Rawat, Mukesh; Dangwal, Anoop; Ramola, R.C.; Prasad, Ganesh; Mishra, Rosaline

    2016-01-01

    Long-term measurements of indoor radon, thoron and their progeny concentrations have been carried out in dwellings of Yamuna and Tons Valleys of Uttarkashi, Garhwal Himalaya to investigate the health risk associated with inhalation of radon, thoron and progeny. The experimentally determined values of radon, thoron and progeny concentrations were used to estimate the annual inhalation doses and annual effective doses. The annual inhalation dose has been found to vary from 0.8 to 3.9 mSv y -1 with an average of 1.8 mSv y -1 . The annual effective dose from the exposure to radon and its progeny in the study area has been found to vary from 0.1 to 2.4 mSv with an average of 1.2±0.6 mSv. Similarly, the annual effective dose due to thoron and its progeny has been found to vary from 0.2 to 1.5 mSv with an average of 0.6±0.4. The measurement techniques and results obtained are discussed in detail. (authors)

  19. Comparison of predicted and measured variations of indoor radon concentration

    International Nuclear Information System (INIS)

    Arvela, H.; Voutilainen, A.; Maekelaeinen, I.; Castren, O.; Winqvist, K.

    1988-01-01

    Prediction of the variations of indoor radon concentration were calculated using a model relating indoor radon concentration to radon entry rate, air infiltration and meteorological factors. These calculated variations have been compared with seasonal variations of 33 houses during 1-4 years, with winter-summer concentration ratios of 300 houses and the measured diurnal variation. In houses with a slab in ground contact the measured seasonal variations are quite often in agreement with variations predicted for nearly pure pressure difference driven flow. The contribution of a diffusion source is significant in houses with large porous concrete walls against the ground. Air flow due to seasonally variable thermal convection within eskers strongly affects the seasonal variations within houses located thereon. Measured and predicted winter-summer concentration ratios demonstrate that, on average, the ratio is a function of radon concentration. The ratio increases with increasing winter concentration. According to the model the diurnal maximum caused by a pressure difference driven flow occurs in the morning, a finding which is in agreement with the measurements. The model presented can be used for differentiating between factors affecting radon entry into houses. (author)

  20. Intercomparison of active and passive instruments for radon and radon progeny in North America

    International Nuclear Information System (INIS)

    George, A.C.; Tu, Keng-Wu; Knutson, E.O.

    1995-02-01

    An intercomparison exercise for radon and radon progeny instruments and methods was held at the Environmental Measurements Laboratory (EML) from April 22--May 2, 1994. The exercise was conducted in the new EML radon test and calibration facility in which conditions of exposure are very well controlled. The detection systems of the intercompared instruments consisted of. (1) pulse ionization chambers, (2) electret ionization chambers, (3) scintillation detectors, (4) alpha particle spectrometers with silicon diodes, surface barrier or diffused junction detectors, (5) registration of nuclear tracks in solid-state materials, and (6) activated carbon collectors counted by gamma-ray spectrometry or by alpha- and beta-liquid scintillation counting. 23 private firms, government laboratories and universities participated with a 165 passive integrating devices consisting of: Activated carbon collectors, nuclear alpha track detectors and electret ionization chambers, and 11 active and passive continuous radon monitors. Five portable integrating and continuous instruments were intercompared for radon progeny. Forty grab samples for radon progeny were taken by five groups that participated in person to test and evaluate their primary instruments and methods that measure individual radon progeny and the potential alpha energy concentration (PAEC) in indoor air. Results indicate that more than 80% of the measurements for radon performed with a variety of instruments, are within ±10% of actual value. The majority of the instruments that measure individual radon progeny and the PAEC gave results that are in good agreement with the EML reference value. Radon progeny measurements made with continuous and integrating instruments are satisfactory with room for improvement

  1. Characteristics of indoor radon and its progeny in a Japanese dwelling while using air appliances

    International Nuclear Information System (INIS)

    Pornnumpa, C.; Tokonami, S.; Sorimachi, A.; Kranrod, C.

    2015-01-01

    Characteristics of radon and its progeny were investigated in different air conditions by turning four types of indoor air appliances on and off in a two-story concrete Japanese dwelling. The four appliances were air conditioner, air cleaner, gas heater and cooker hood. The measurements were done using two devices: (1) a Si-based semiconductor detector for continuous measurement of indoor radon concentration and (2) a ZnS(Ag) scintillation counting system for equilibrium-equivalent radon concentration. Throughout the entire experiment, the cooker hood was the most effective in decreasing indoor radon concentration over a long period of time and the less effective was the air conditioner, while the air cleaner and gas heater did not affect the concentration of radon. However, the results measured in each air condition will differ according to the lifestyles and activities of the inhabitants. In this study, indoor radon and its progeny in a Japanese dwelling will be characterised by the different air conditions. (authors)

  2. Particle size distribution of the radon progeny and ambient aerosols in the Underground Tourist Route “Liczyrzepa” Mine in Kowary Adit

    Directory of Open Access Journals (Sweden)

    Wołoszczuk Katarzyna

    2018-01-01

    Full Text Available Central Laboratory for Radiological Protection, in cooperation with Central Mining Institute performed measurements of radon concentration in air, potential alpha energy concentration (PAEC, particle size distribution of the radon progeny and ambient aerosols in the Underground Tourist-Educational Route “Liczyrzepa” Mine in Kowary Adit. A research study was developed to investigate the appropriate dose conversion factors for short-lived radon progeny. The particle size distribution of radon progeny was determined using Radon Progeny Particle Size Spectrometer (RPPSS. The device allows to receive the distribution of PAEC in the particle size range from 0.6 nm to 2494 nm, based on their activity measured on 8 stages composed of impaction plates or diffusion screens. The measurements of the ambient airborne particle size distribution were performed in the range from a few nanometres to about 20 micrometres using Aerodynamic Particle Sizer (APS spectrometer and the Scanning Mobility Particle Sizer Spectrometer (SMPS.

  3. Design of a recirculating radon progeny aerosol generation and animal exposure system

    International Nuclear Information System (INIS)

    Newton, G.J.; Cuddihy, R.G.; Yeh, H.C.; Barr, E.B.; Boecker, B.B.

    1988-01-01

    Inhalation studies are being conducted at ITRI using laboratory animals exposed to radon-222 progeny attached to vector aerosols that are typical of indoor environments. The purpose of these studies is to identify the cells at risk from inhaled radon progeny and their locations within the respiratory tract. These studies require exposures up to 1000 working level months (WLM) within a few hours. Thus, large amounts of radium-226 are needed to produce the gaseous radon-222. A once-through-exposure-system was considered to be impractical because of statutory discharge limitations and the large amounts of radium that would be required. Therefore, a recirculating exposure system was designed and constructed that removes the aerosol after passing through the exposure chambers and recirculates purified air and radon. The purified radon is mixed with freshly evolving radon from a radon generator and passed Into a reaction-aging chamber where attachment of radon progeny to the vector aerosol occurs. The design includes: (1) 50-200 mg radium-226 in a radon generator, (2) 40 L/min total flow rate, (3) CO 2 removal, (4) reconstitution of oxygen tension and water vapor content to atmospheric levels, and (5) a trap for radon gas. A radon progeny exposure concentration in the range of 4,000 to 50,000 WL is being produced. (author)

  4. Occurrence of 222Rn and progeny in natural gas processing plants in western Canada

    International Nuclear Information System (INIS)

    Drummond, I.; Boucher, P.; Bradford, B.; Evans, H.; McLean, J.; Reczek, E.; Thunem, H.

    1990-01-01

    In Western Canada, there are many plants that process natural gas to remove impurities (CO 2 , H 2 S, H 2 O) and recover natural gas liquids (propane, butane, etc.). Trace quantities of 222 Rn present in the inlet stream are concentrated in streams rich with propane. Potential hazards to plant operators include direct inhalation of 222 Rn and progeny; exposure to gamma radiation from short-lived progeny deposited inside equipment; or inhalation of 210 Pb when contaminated equipment is opened for repair. Twenty-four plants operated by seven companies cooperated to assess these potential hazards. The findings indicate a substantial flux of 222 Rn and progeny passing through the plants, but little accumulation of radionuclides. In no case was there evidence of significant exposure of plant operators or maintenance personnel to ionizing radiation. Further investigation of pipeline operations, and chemical operations using natural gas liquids as feed stock, is recommended

  5. Measurement of the radon concentration in an underground public facility and dose assessment. Fukuoka Tenjin Shopping Center

    International Nuclear Information System (INIS)

    Narazaki, Yukinori; Tokonami, Shinji; Sanada, Tetsuya; Kanno, Nobuyuki; Yamada, Yuji

    2000-01-01

    Radon concentrations were measured with a passive radon detector from April 1998 through June 1999 in the Fukuoka Tenjin Underground Shopping Center to assess the dose affecting workers because of radon progeny inhalation. The radon concentration during the period was distributed from a range of 1.9 to 13.6 Bq/m 3 . The arithmetic average concentration was estimated to be 6.9±2.4 Bq/ 3 . The radon level was lower than that in dwellings in Japan and other countries. No spatial distribution of radon concentration was found in that area. From continuous measurement, the radon concentration was found to be high from midnight to noon and low in the afternoon. Little difference was noted between the daily average radon concentration and that during working hours. There was no seasonal variation. The equilibrium factor of 0.21±0.10 was obtained during working hours. The activity-weighted size distribution of radon progeny was evaluated by using the number distribution of ambient aerosols and the classical attachment theory. Consequently, the activity median diameter was 150 nm. The unattached fraction of radon progeny was estimated to be 0.025 with an empirical equation. The annual effective dose of workers at the Tenjin center was calculated with the dose conversion factor from the UNSCEAR 1993 report and estimated to be 0.024 mSv/y. (author)

  6. Detection of 210Po on filter papers 16 years after use for the collection of short-lived radon progeny in a room

    International Nuclear Information System (INIS)

    Abu-Jarad, F.; Fazal-ur-Rehman

    2003-01-01

    Radon gas was allowed to accumulate in its radium source and then injected into a 36 m 3 test room, resulting in an initial radon concentration of 15 kBq m -3 . Filter papers were used to collect the short-lived radon progeny and thus to measure the Potential Alpha Energy Concentration (PAEC) in-situ in the year 1984 at different times and conditions according to the experimental design. The radon progeny collected on the filter papers were studied as a function of aerosol particle concentration ranging from 10 2 -10 5 particles cm -3 in three different experiments. The highest aerosol particle concentration was generated by indoor cigarette smoking. Those filters were stored after the experiment, and were used after 16 years to study the activity of the radon long-lived alpha emitter progeny, 210 Po (T 1/2 =138 days). This isotope is separated from the short-lived progeny by 210 Pb beta emitter with 22.3 years half-life. After 16 years' storage of these filters, each filter paper was sandwiched and wrapped between two CR-39 nuclear track detectors, to put the detectors in contact with the surfaces of different filters, for 337 days. Correlation between the PAEC measured using filter papers in the year 1984 and the activity of long-lived alpha emitter 210 Po on the same filter papers measured in the year 2000 were studied. The results of the 210 Po activity showed a very good correlation of 0.92 with the PAEC 16 years ago. The results also depict that the PAEC and 210 Po activity in indoor air increased with the increase of aerosol particle concentration, which shows the attachment of short-lived radon progeny with the aerosol particles. The experiment proves that indoor cigarette smoking is a major source of aerosol particles carrying radon progeny and, thus, indoor cigarette smoking is an additional source of internal radiation hazard to the occupants whether smoker or non-smoker

  7. Assessment of indoor radon, thoron concentrations, and their relationship with seasonal variation and geology of Udhampur district, Jammu & Kashmir, India.

    Science.gov (United States)

    Kumar, Ajay; Sharma, Sumit; Mehra, Rohit; Narang, Saurabh; Mishra, Rosaline

    2017-07-01

    Background The inhalation doses resulting from the exposure to radon, thoron, and their progeny are important quantities in estimating the radiation risk for epidemiological studies as the average global annual effective dose due to radon and its progeny is 1.3 mSv as compared to that of 2.4 mSv due to all other natural sources of ionizing radiation. Objectives The annual inhalation dose has been assessed with an aim of investigating the health risk to the inhabitants of the studied region. Methods Time integrated deposition based 222 Rn/ 220 Rn sensors have been used to measure concentrations in 146 dwellings of Udhampur district, Jammu and Kashmir. An active smart RnDuo monitor has also been used for comparison purposes. Results The range of indoor radon/thoron concentrations is found to vary from 11 to 58 Bqm -3 with an average value of 29 ± 9 Bqm -3 and from 25 to 185 Bqm -3 with an average value of 83 ± 32 Bqm -3 , respectively. About 10.7% dwellings have higher values than world average of 40 Bqm -3 prescribed by UNSCEAR. The relationship of indoor radon and thoron levels with different seasons, ventilation conditions, and different geological formations have been discussed. Conclusions The observed values of concentrations and average annual effective dose due to radon, thoron, and its progeny in the study area have been found to be below the recommended level of ICRP. The observed concentrations of 222 Rn and 220 Rn measured with active and passive techniques are found to be in good agreement.

  8. Variations of Rn-222 concentration in the Bratislava air

    International Nuclear Information System (INIS)

    Holy, K.; Bohm, R.; Polaskova, A.

    1996-01-01

    222 Rn is produced by alpha decay of 222 Ra in roil. A small fraction of totally produced 222 Rn escapes from coil particles into soil air. Then 222 Rn is transported predominantly by molecular diffusion into outdoor atmosphere. The radon concentration in the outdoor atmosphere is not stable. It varies irregularly depending on meteorological conditions. However there were found out regular daily and remand variations of 222 Rn concentration in outdoor atmosphere. These variations were measured in numerous works and results are summarized f.e. in work of Gesell. A simple model described the annual variations of 222 Rn concentration war published by Minato. A mathematical analysis of daily course of 222 Rn concentration in outdoor atmosphere was realized by Garzon et al. Some results of our study of 222 Rn variations in outdoor atmosphere of Bratislava are shown in this report. (author)

  9. STUDY OF RADIATION EXPOSURE DUE TO RADON, THORON AND PROGENY IN THE INDOOR ENVIRONMENT OF YAMUNA AND TONS VALLEYS OF GARHWAL HIMALAYA.

    Science.gov (United States)

    Prasad, Mukesh; Rawat, Mukesh; Dangwal, Anoop; Prasad, Ganesh; Mishra, Rosaline; Ramola, R C

    2016-10-01

    Long-term measurements of indoor radon, thoron and their progeny concentrations have been carried out in dwellings of Yamuna and Tons Valleys of Uttarkashi, Garhwal Himalaya to investigate the health risk associated with inhalation of radon, thoron and progeny. The experimentally determined values of radon, thoron and progeny concentrations were used to estimate the annual inhalation doses and annual effective doses. The annual inhalation dose has been found to vary from 0.8 to 3.9 mSv y -1 with an average of 1.8 mSv y -1 The annual effective dose from the exposure to radon and its progeny in the study area has been found to vary from 0.1 to 2.4 mSv with an average of 1.2±0.6 mSv. Similarly, the annual effective dose due to thoron and its progeny has been found to vary from 0.2 to 1.5 mSv with an average of 0.6±0.4. The measurement techniques and results obtained are discussed in detail. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.

    1992-07-01

    This report covers the second year of the 28 month grant current grant to Clarkson University to study the chemical and physical behavior of the polonium 218 atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and it dose to the cells in the respiratory tract are to be fully assessed. Two areas of radon progeny behavior are being pursued; laboratory studies under controlled conditions to better understand the fundamental physical and chemical process that affect the progeny's atmospheric behavior and studies in actual indoor environments to develop a better assessment of the exposure of the occupants of that space to the size and concentration of the indoor radioactive aerosol. This report describes the progress toward achieving these objectives.

  11. Detection of {sup 210}Po on filter papers 16 years after use for the collection of short-lived radon progeny in a room

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Jarad, F. E-mail: falah.abujarad@aramco.com; Fazal-ur-Rehman

    2003-07-01

    Radon gas was allowed to accumulate in its radium source and then injected into a 36 m{sup 3} test room, resulting in an initial radon concentration of 15 kBq m{sup -3}. Filter papers were used to collect the short-lived radon progeny and thus to measure the Potential Alpha Energy Concentration (PAEC) in-situ in the year 1984 at different times and conditions according to the experimental design. The radon progeny collected on the filter papers were studied as a function of aerosol particle concentration ranging from 10{sup 2}-10{sup 5} particles cm{sup -3} in three different experiments. The highest aerosol particle concentration was generated by indoor cigarette smoking. Those filters were stored after the experiment, and were used after 16 years to study the activity of the radon long-lived alpha emitter progeny, {sup 210}Po (T{sub 1/2}=138 days). This isotope is separated from the short-lived progeny by {sup 210}Pb beta emitter with 22.3 years half-life. After 16 years' storage of these filters, each filter paper was sandwiched and wrapped between two CR-39 nuclear track detectors, to put the detectors in contact with the surfaces of different filters, for 337 days. Correlation between the PAEC measured using filter papers in the year 1984 and the activity of long-lived alpha emitter {sup 210}Po on the same filter papers measured in the year 2000 were studied. The results of the {sup 210}Po activity showed a very good correlation of 0.92 with the PAEC 16 years ago. The results also depict that the PAEC and {sup 210}Po activity in indoor air increased with the increase of aerosol particle concentration, which shows the attachment of short-lived radon progeny with the aerosol particles. The experiment proves that indoor cigarette smoking is a major source of aerosol particles carrying radon progeny and, thus, indoor cigarette smoking is an additional source of internal radiation hazard to the occupants whether smoker or non-smoker.

  12. Attachment of radon progeny to cigarette-smoke aerosols

    International Nuclear Information System (INIS)

    Biermann, A.H.; Sawyer, S.R.

    1995-05-01

    The daughter products of radon gas are now recognized as a significant contributor to radiation exposure to the general public. It is also suspected that a synergistic effect exists with the combination cigarette smoking and radon exposure. We have conducted an experimental investigation to determine the physical nature of radon progeny interactions with cigarette smoke aerosols. The size distributions of the aerosols are characterized and attachment rates of radon progeny to cigarette-smoke aerosols are determined. Both the mainstream and sidestream portions of the smoke aerosol are investigated. Unattached radon progeny are very mobile and, in the presence of aerosols, readily attach to the particle surfaces. In this study, an aerosol chamber is used to contain the radon gas, progeny and aerosol mixture while allowing the attachment process to occur. The rate of attachment is dependent on the size distribution, or diffusion coefficient, of the radon progeny as well as the aerosol size distribution. The size distribution of the radon daughter products is monitored using a graded-screen diffusion battery. The diffusion battery also enables separation of the unattached radon progeny from those attached to the aerosol particles. Analysis of the radon decay products is accomplished using alpha spectrometry. The aerosols of interest are size fractionated with the aid of a differential mobility analyzer and cascade impactor. The measured attachment rates of progeny to the cigarette smoke are compared to those found in similar experiments using an ambient aerosol. The lowest attachment coefficients observed, ∼10 -6 cm 3 /s, occurred for the ambient aerosol. The sidestream and mainstream smoke aerosols exhibited higher attachment rates in that order. The results compared favorably with theories describing the coagulation process of aerosols

  13. Diurnal Variation of Radon Concentration in the Postojna Cave

    International Nuclear Information System (INIS)

    Gregoric, A.; Vaupotic, J.

    2011-01-01

    Postojna Cave, with 20 km of galleries, is the longest known cave system and also the largest of about 20 show caves in Slovenia and one of the most visited show caves in the world. It is well known that high concentrations of radon are common in karstic caves, although quantities of uranium (238U) in limestone are rather low. The reason for this is low natural ventilation of the underground cavities. Tectonic faults constitute an additional source of radon. Variations of radon concentration in cave air arise from a balance of the emission from cave surfaces and drip waters, decay in cave air, and exchange with the outside atmosphere. Because of its elevated radon concentrations, Postojna Cave has been under permanent radon survey since 1995. The influence of meteorological conditions on the radon levels and their temporal variations depends mostly on the shape of the cave, and the number and directions of cracks, corridors and fissures connecting the cave rooms with the outside atmosphere. The driving force for air movement in horizontal caves, and thus the inflow of fresh air and release of the cave air to the atmosphere, is the temperature difference between the cave air and outdoors, which causes seasonal pattern of radon concentration in the cave with high levels in summer and low in winter. However, on a daily scale different behaviour of radon can be observed at different locations in the cave. In this paper diurnal variation of radon concentration at two locations is presented and discussed. Postojna Cave is a horizontal cave with a stable yearly temperature around 10 degrees of @C. Continuous measurements of radon concentration were carried out from 2005 to 2010 at two locations along the guided tourist trail. Radon concentration was measured with Radim 5 WP monitors (SMM Company, Prague, Czech Republic) with sampling frequency once an hour. The evaluation of five-year radon monitoring at two sites in the Postojna Cave reveals significant diurnal and

  14. Characteristics of indoor radon and its progeny in a Japanese dwelling while using air appliances.

    Science.gov (United States)

    Pornnumpa, C; Tokonami, S; Sorimachi, A; Kranrod, C

    2015-11-01

    Characteristics of radon and its progeny were investigated in different air conditions by turning four types of indoor air appliances on and off in a two-story concrete Japanese dwelling. The four appliances were air conditioner, air cleaner, gas heater and cooker hood. The measurements were done using two devices: (1) a Si-based semiconductor detector for continuous measurement of indoor radon concentration and (2) a ZnS(Ag) scintillation counting system for equilibrium-equivalent radon concentration. Throughout the entire experiment, the cooker hood was the most effective in decreasing indoor radon concentration over a long period of time and the less effective was the air conditioner, while the air cleaner and gas heater did not affect the concentration of radon. However, the results measured in each air condition will differ according to the lifestyles and activities of the inhabitants. In this study, indoor radon and its progeny in a Japanese dwelling will be characterised by the different air conditions. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Attached and Unattached Activity Size Distribution of Short-Lived Radon Progeny (214Pb) and Evaluation of Deposition Fraction

    International Nuclear Information System (INIS)

    Mohamed, A.; Ahmed, A.A.; Ali, A.E.; Yuness, M.

    2009-01-01

    Inhalation of 2 '2 2 Rn progeny in the domestic environment contributes the greatest fraction of the natural radiation exposure to the public. Dosimetric models are most often used in the assessment of human lung doses due to inhaled radioactivity because of the difficulty in making direct measurements. These models require information about the parameters of activity size distributions of radon progeny. The current study presents measured data on the attached and unattached activity size distributions of radon progeny in indoor air in El-Minia, Egypt. The attached fraction was collected using a low pressure Berner cascade impactor technique. A screen diffusion battery was used for collecting the unattached fraction. Most of the attached activities for 222 Rn progeny were associated with aerosol particles of the accumulation mode. The mean activity median aerodynamic diameter (AMAD) of this mode for 21 4 P b was determined to be 401 nm with relative mean geometric standard deviation of 2.96. The mean value of specific air activity concentration of 214 Pb associated with that mode was determined to be 4.74 %0.44 Bq m -3 . The relative mean geometric standard deviations of unattached 214 Pb was determined to be 1.21 with the mean activity thermodynamic diameter (AMTD) of 1.2 nm. The mean unattached activity concentration of 214 Pb was found to be 0.44%0.14 Bq m-3. Based on the obtained results of radon progeny size distributions (unattached and attached), the deposition fractions in each airway generation of the human lung were evaluated by using a lung deposition model

  16. Progeny testing: proceedings of servicewide genetics workshop

    Science.gov (United States)

    Dick Miller

    1984-01-01

    The primary objective of this workshop was to discuss in detail the state- of-the-art of progeny testing. All aspects, from setting objectives through data collection and analysis, was be covered. We all know progeny testing is a highly technical phase of our tree improvement programs. Each task is critical and must be performed accurately and within a prescribed time...

  17. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres. Progress report, May 1, 1993--January 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.

    1993-01-01

    Progress is reported on the chemical and physical behavior of the {sup 218}Po atom immediately following its formation by the alpha decay of radon. Two areas of radon progeny behavior are being pursued; laboratory studies under controlled conditions to better understand the fundamental physical and chemical processes that affect the progeny`s atmospheric behavior and studies in actual indoor environments to develop a better assessment of the exposure of the occupants of that space to the size and concentration of the indoor radioactive aerosol. The specific tasks addressed were to determine the formation rates of {center_dot}OH radicals formed by the radiolysis of air following radon decay, to examine the formation of particles by the radiolytic oxidation of substances like SO{sub 2}, ethylene, and H{sub 2}S to lower vapor pressure compounds and determine the role of gas phase additives such as H{sub 2}O and NH{sub 3} in determining the particle size, to measure the rate of ion-induced nucleation using a thermal diffusion cloud chamber, and to measure the neutralization rate of {sup 218}PoO{sub x}{sup +} in O{sub 2} at low radon concentrations. Initial measurements were conducted of the activity size distributions in actual homes with occupants present so that the variability of the indoor activity size distributions can be assessed with respect to indoor aerosol sources and general lifestyle variations of the occupants. A prospective study of the utility of measurement of deposited {sup 210}Pb embedded in glass surfaces as a measure of the long-term, integrated exposure of the population to radon are described. Methodology was developed to determine the hygroscopicity of the indoor aerosol so that the changes in deposition efficiency of the radioactive indoor aerosol with hygroscopic growth in the respiratory tract can be assessed.

  18. Weekday variation in triglyceride concentrations in 1.8 million blood samples

    DEFF Research Database (Denmark)

    Jaskolowski, Jörn; Ritz, Christian; Sjödin, Anders Mikael

    2017-01-01

    BACKGROUND: Triglyceride (TG) concentration is used as a marker of cardio-metabolic risk. However, diurnal and possibly weekday variation exists in TG concentrations. OBJECTIVE: To investigate weekday variation in TG concentrations among 1.8 million blood samples drawn between 2008 and 2015 from...... variations in TG concentrations were recorded for out-patients between the age of 9 to 26 years, with up to 20% higher values on Mondays compared to Fridays (all PTriglyceride concentrations were highest after the weekend and gradually declined during the week. We suggest that unhealthy...

  19. Diurnal measurement of equilibrium equivalent radon/thoron concentration using time integrated flow mode grab sampler

    International Nuclear Information System (INIS)

    Pant, P.; Kandari, T.; Ramola, R.C.; Semwal, C.P.; Prasad, M.

    2018-01-01

    The basic processes which influenced the concentration of radon and thoron decay products are- attachment, recoil and deposition and by the room specific parameters of radon exhalation and ventilation. The freshly formed decay products have a high diffusivities (especially in air) and ability to stick to surfaces. According to UNSCEAR 1977, radon daughters may be combined as the so called equilibrium equivalent concentration which is related to the potential alpha energy distribution concentration. In the present study an effort has been made to see the diurnal variation of radon and thoron progeny concentration using time integrated flow mode sampler

  20. Deposition Pattern of Inhaled Thoron Progeny Size Distribution in Human Lung

    International Nuclear Information System (INIS)

    Mohamed, A.

    2005-01-01

    One of the important factors controlling the distribution of radiation dose to the different portions of the human respiratory tract is the deposition pattern of thoron progeny containing aerosol. Based on the activity size distribution parameters of thoron progeny, which were measured in El-Minia University, the deposition behavior of thoron progeny (attached and unattached) has been studied by using a stochastic deposition model. The measurements were performed with a wire screen diffusion battery and a low pressure cascade impactor (type Berner). The bronchial deposition efficiencies of particles in the size range of attached thoron progeny were found to be lower than those of unattached progeny. The effect of thoron progeny deposition by adult male has been also studied for various levels of physical exertion. An increase in the breathing rate was found to decrease the efficiencies with which inhaled progeny were deposited in the bronchi. As the ventilation rate increases from 0.54 to 1.5 m3 h-1, the average deposition efficiencies of airway generation 1 through 8 are expected to decrease by 22 % for 1.4 nm particles and by 38 % for 150 nm particles

  1. Utilisation of an Air-conditioning System to Control the Levels of Radon and Radon Progeny in a Workplace Environment

    International Nuclear Information System (INIS)

    Marley, F.

    2000-01-01

    From long-term real-time radon and radon progeny measurements taken in a relatively large retail store, cyclical patterns were evident, which were found to relate to the overriding influence of the timed air-conditioning system. Concentration of radon, radon progeny and the variability of F factor were found to depend significantly on the intermittent operation of this ventilation-air-conditioning system. After pressure equalisation remedial measures proved ineffective, the air-movement system was utilised to reduce the levels of radon and radon progeny to well within established norms applicable during working hours. It is demonstrated that the average levels for radon and radon progeny are reduced in absolute terms. This amounted to less than 12% of the general level, during designated work periods. Where air movement systems are already installed, as well as other circumstances, their regulation provides an economical solution to meeting legal and other standards for radon in the workplace. (author)

  2. Variation of atmospheric 210Pb concentration in the inland area of Chinese continent

    International Nuclear Information System (INIS)

    Doi, Taeko; Sato, Jun.

    1995-01-01

    Atmospheric concentrations of 210 Pb and their variations over Urumqi, Lanzhou and Baotou, cities located in inland area of Chinese continent, were observed for a period of 1 year in 1992. The monthly average concentrations ranged from 0.27 to 4.57 mBq/m 3 . The concentrations over these cities in winter were several times higher than that observed at Tsukuba Science City, Japan, and the range of variation was also larger. The variations in concentration over the 3 localities were similar to each other, showing the same seasonal variation pattern: low concentration appeared in summer and high in winter. This variation pattern was different from that observed at Tsukuba Science City. The variations in concentration over Chinese continent, where precipitation is much lower than that in Japan, correlated quite well with the variation in precipitation. (author)

  3. Genetic parameters and estimated genetic gains in young rubber tree progenies

    Directory of Open Access Journals (Sweden)

    Cecília Khusala Verardi

    2013-04-01

    Full Text Available The objective of this work was to assess the genetic parameters and to estimate genetic gains in young rubber tree progenies. The experiments were carried out during three years, in a randomized block design, with six replicates and ten plants per plot, in three representative Hevea crop regions of the state of São Paulo, Brazil. Twenty-two progenies were evaluated, from three to five years old, for rubber yield and annual girth growth. Genetic gain was estimated with the multi-effect index (MEI. Selection by progenies means provided greater estimated genetic gain than selection based on individuals, since heritability values of progeny means were greater than the ones of individual heritability, for both evaluated variables, in all the assessment years. The selection of the three best progenies for rubber yield provided a selection gain of 1.28 g per plant. The genetic gains estimated with MEI using data from early assessments (from 3 to 5-year-old were generally high for annual girth growth and rubber yield. The high genetic gains for annual girth growth in the first year of assessment indicate that progenies can be selected at the beginning of the breeding program. Population effective size was consistent with the three progenies selected, showing that they were not related and that the population genetic variability is ensured. Early selection with the genetic gains estimated by MEI can be made on rubber tree progenies.

  4. Internal microdosimetry of inhaled radon progeny in bronchial airways: advantages and limitations

    International Nuclear Information System (INIS)

    Hofmann, Werner; Fakir, Hatim; Pihet, Pascal

    2007-01-01

    The objective of the present study was to identify advantages and limitations of the application of microdosimetric concepts for inhaled radon progeny activities in the lungs. The methods employed for this analysis were a recently developed Monte- Carlo microdosimetry code for the calculation of energy deposition in bronchial target cells and the Probability Per Unit Track Length (PPUTL) model, which relates these microdosimetric parameters to cellular radiation effects. The major advantages of internal microdosimetry of radon progeny in bronchial airways are: (i) quantitative characterisation of non-uniform dose distributions and identification of target sites with enhanced carcinogenic potential, (ii) quantification of low doses of alpha particles by the number of cells hit and the dose received by those cells, (iii) illustration of the random variations of cellular doses by specific energy distributions and (iv) establishment of a direct link to cellular radiobiological effects. At present, a major limitation of microdosimetry is the extrapolation of the response of individual cells to the resulting tissue response, which is still not fully explored. (authors)

  5. Daily and seasonal variation of short-lived radon decay product concentrations in ground-level air at Munich-Neuherberg - a long-term study

    International Nuclear Information System (INIS)

    Winkler, R.

    2001-09-01

    Daily and seasonal variation of the equilibrium equivalent radon concentration (EEC Rn-222 ) and of the concentration of the short-lived radon decay product 214 Pb in ground-level air was investigated at Munich-Neuherberg from 1982 to 2000, and from 1989 to 2000, respectively. For this, the EEC was measured continuously with an alpha/beta aerosol monitor at 2.5 m above ground, and 214 Pb was determined by online gamma spectrometry at about 12 m above ground. The resulting time series were analysed statistically. For the respective periods, the measurements yielded a long-term average concentration of 7.8 Bq m -3 (geometric mean: 6.1 Bq m -3 ) for the EEC, and 6.0 Bq m -3 (geom. mean: 5.0 Bq m -3 ) for 214 Pb. In these periods, daily averages ranged from 0.6 to 49 Bq m -3 (EEC), and from 0.6 to 43 Bq m -3 ( 214 Pb). Monthly mean concentrations varied between 3.0 Bq m -3 in March 1988 and 20 Bq m -3 in October 1985 (EEC), and from 3.4 Bq m -3 in April 1992 to 11 Bq m -3 in October 1995 ( 214 Pb), respectively. The annual average concentrations were from 5.9 Bq m -3 in 1999 to 10.6 Bq m -3 in 1985 (EEC), and from 5.3 Bq m -3 in 1999 to 6.8 Bq m -3 in 1991 ( 214 Pb). From the long-term average equilibrium equivalent radon concentration (EEC), an average annual effective dose of 0.13 mSv due to the short-lived radon progeny outdoors was estimated. The time series showed distinct daily and seasonal variations. The variations from day to day are mainly caused by the actual weather conditions (wind, rain, etc.), i.e. the short-term turbulent conditions. The seasonal pattern is characterised by an autumn to winter maximum and an early summer minimum, and reflects the prevailing turbulent conditions at the respective seasons. As known, at Munich-Neuherberg during autumn and winter months (October/November to February) inversion weather conditions frequently occur, while the other months are characterised by more turbulent conditions. (orig.)

  6. Comparison of different methods for thoron progeny measurement

    International Nuclear Information System (INIS)

    Bi Lei; Zhu Li; Shang Bing; Cui Hongxing; Zhang Qingzhao

    2009-01-01

    Four popular methods for thoron progeny measurement were discussed, including the aspects of detector,principle, precondition, calculation advantages and disadvantages. Comparison experiments were made in mine and houses with high background in Yunnan Province. Since indoor thoron progeny changes with time obviously and with no rule, α track method is recommended in the area of radiation protection for environmental detection and assessment. (authors)

  7. Rapid determination of radon daughter concentrations

    International Nuclear Information System (INIS)

    Bigu, J.

    1990-08-01

    A technical evaluation of four radon 222 progeny measuring instruments has been conducted. The evaluation has been carried out under laboratory controlled conditions and at several locations in an underground uranium mine. The laboratory evaluation consisted of a thorough study of the behaviour and performance of the instruments under a wide variety of environmental conditions such as radon 222 gas concentration, radon 222 progeny concentration, temperature, relative humidity, aerosol concentration, and gamma-field exposure. The four instruments tested were: the Pylon WL-1000C, the MDA IWLM-811, the MIMIL IIM, and the EDA WLM-30. The readings of the instruments were compared with a widely accepted radon 222 progeny concentration measuring method, namely, the Thomas-Tsivoglou method. Two variables affected two instruments significantly, namely, under high aerosol concentration conditions, one of the instruments (EDA WLM-30) ceased to operate because of filter loading. The other variable was gamma-field exposure which affected another instrument (MDA-811) adversely. The instruments were rated according to several criteria. The overall best performer was the MIMIL IIM, although other instruments also fared quite well under a variety of experimental conditions

  8. An overview of thoron and its progeny in the indoor environment

    International Nuclear Information System (INIS)

    McLaughlin, J.

    2010-01-01

    An account is given of the behaviour of thoron and its progeny in the indoor environment. Emphasis is placed on the spatial distribution of these radionuclides in room air and on their interactions with indoor aerosols. How these aspects of thoron and progeny behaviour give rise to special problems for measuring them and assessing their radiological impact are described. Descriptions and comparisons are given of a range of thoron and progeny measurement techniques both passive and active. Recent progress in thoron dosimetry is described as well as compared with radon dosimetry. The results of some indoor thoron and progeny surveys carried out in different countries in recent years are given. As an example of this a summary account is presented of a recently concluded survey of thoron and its airborne progeny in over 200 houses in Ireland. (authors)

  9. Concentration variation of radon in the room

    International Nuclear Information System (INIS)

    Komaruzaman Mohd Noor; Haziman Hassan; Rosli Mahat; Yusof Md Amin

    1995-01-01

    The study was carried out to determine the variation of radon concentration in the room. Radon detector used was solid nuclear tracks detector (SSNTD) LR-115. From this result, suitable points to make radon measurement was determined

  10. Seasonal variation in heavy metal concentration in mangrove foliage

    Digital Repository Service at National Institute of Oceanography (India)

    Untawale, A.G.; Wafar, S.; Bhosle, N.B.

    Seasonal variation in the concentration of some heavy metals in the leaves of seven species of mangrove vegetation from Goa, revealed that maximum concentration of iron and manganese occurs during the monsoon season without any significant toxic...

  11. Variação genética em progênies de Myracrodruon urundeuva F.F. & M.F. Allemão em três sistemas de cultivo Genetic variation in progenies of Myracrodruon urundeuva F.F. & M.F. Allemao in three cultivation systems

    Directory of Open Access Journals (Sweden)

    Miguel Luiz Menezes Freitas

    2006-06-01

    Full Text Available Myracrodruon urundeuva (aroeira é uma das espécies arbóreas que apresentam madeira de maior durabilidade em contato com o solo. Em razão dessa característica, populações naturais de M. urundeuva, distribuídas por quase todo o Brasil, vêm sendo dizimadas. Desse modo, o presente trabalho teve por objetivo avaliar a expressão da variação genética em uma população natural de M. urundeuva procedente da Estação Ecológica do Instituto Florestal, localizada em Paulo de Faria, SP. Coletaram-se sementes de 30 árvores de polinização livre, em setembro de 1996. Com esse material, foram instalados três testes de progênies em diferentes sistemas de plantio em Selvíria, MS, obedecendo a um delineamento em blocos casualizados, com 30 tratamentos (progênies e três repetições. Foi assumido o modelo de cruzamento misto para essa espécie. Verificou-se que houve diferença significativa nos efeitos de progênies e ambiente (testes de progênies, e a interação progênies x ambientes não foi significativa. Desse modo, as progênies apresentaram comportamento semelhante nos diferentes ambientes. A melhor "performance" das progênies foi no plantio envolvendo M. urundeuva, Guazuma ulmifolia (Lam e Anandenanthera falcata (Benth. Speg., as quais também apresentaram considerável variação genética, indicando alto valor para programas de conservação e melhoramento genético.Myracrodruon urundeuva is one of the tree species the wood that presents the longest durability when in contact with soil. Because of this characteristic, populations of M. urundeuva have been decimated throughout Brazil. Therefore, this work aimed at analyzing the expression of genetic variation in a natural population of M. urundeuva from the Ecological Station of the Forest Institute, located in Paulo de Faria-SP. Seeds were collected from 30 free-pollination trees in September, 1996. By using this material, three progeny trials were installed in different

  12. Optimizing the number of progenies and replications in plant breeding experiments

    Directory of Open Access Journals (Sweden)

    João Luís da Silva Filho

    2013-01-01

    Full Text Available A determination criterion was proposed for the number of replications, r, and of evaluated progenies, Nr, given P experimentalplots, with Nr=P/r, and n progenies to be selected; its application was discussed in the selection of progenies of bulk populations,derived from two homozygous parents. For a known heritability at the plot level, h20, there is a critical n below which the gain isgreater with selection evaluating P/(r+1 progenies in r+1 than P/r progenies in r replications. Different h20 scenarios were simulatedin the F2 and F∞ generations, assuming no dominance. It was demonstrated that at any h20 , if n > 18.5% of P, larger gains are obtainedby assuming Nr = P, showing that the augmented block design could be used in the early stages of breeding programs. The higher h20,the higher must be the selection intensity to justify the use of additional replications.

  13. Studies of Radon and Radon Progeny in Air Conditioned Rooms in Hospitals

    International Nuclear Information System (INIS)

    Marley, F.; Denman, A.R.; Phillips, P.S.

    1998-01-01

    A series of continuous real-time radon and radon progeny measurements together with passive etched track detector measurements were performed in hospital premises during 1996. In one small room, detailed measurements over several weeks showed that both the radon concentration and the Equilibrium Factor depended on the intermittent operation of a filtered positive pressure displacement air-conditioning system, which was designed to conform to operating theatre standards. The average radon level measured while the air-conditioning was off was almost four times higher than that recorded whilst it was on. The progeny level was over five times higher than that whilst it was on. Thus, the Equilibrium Factor (F), was significantly lower when the air-conditioning was on. Measurements in similar rooms in two hospitals, confirmed that the reduction in radon level was a general finding. Thus staff working in such environments receive significantly lower radiation dose from radon than staff working in nearby normally ventilated rooms. (author)

  14. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres. Progress report, July 1, 1991--June 30, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.

    1992-07-01

    This report covers the second year of the 28 month grant current grant to Clarkson University to study the chemical and physical behavior of the polonium 218 atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and it dose to the cells in the respiratory tract are to be fully assessed. Two areas of radon progeny behavior are being pursued; laboratory studies under controlled conditions to better understand the fundamental physical and chemical process that affect the progeny`s atmospheric behavior and studies in actual indoor environments to develop a better assessment of the exposure of the occupants of that space to the size and concentration of the indoor radioactive aerosol. This report describes the progress toward achieving these objectives.

  15. Cytogenetic changes in the liver of progeny of irradiated male rats

    Energy Technology Data Exchange (ETDEWEB)

    Kropacova, K.; Slovinska, L.; Misurova, E. [P.J. Safarik Univ., Kosice (Slovakia)

    2002-06-01

    The transgenerational transmission of radiation damage of rat genom was studied on the basis of cytogenetic changes in somatic cells (hepatocytes). It was found, that the irradiation of rat males with dose of 3 Gy of gamma radiation caused latent cytogenetic damage to the liver, which was expressed during the course of an induced proliferation of hepatocytes (by partial hepatectomy) by lower proliferative activity and a high frequency of chromosomal aberrations. In the progeny of irradiated males (in the F{sub 1} generation), the radiation damage to DNA was manifested by similar changes, i.e. by lower proliferation activity and increase in ''spontaneous'' chromosomal aberration occurrence in liver regeneration after partial hepatectomy. Irradiating the progeny of irradiated males (the total radiation load of the progeny being 3 Gy+3 Gy) caused slighter changes in compared with irradiating the progeny of non-irradiated control males (the total radiation load of the progeny being 0 Gy+3 Gy), which suggests some kind of adaptive response, which was also found in other experimental systems and parameters. An analogous course of RNA and DNA quantitative changes in the liver of the F{sub 0} and F{sub 1} generations of rats confirms the partial transmission of radiation damage of genom to the progeny. (author)

  16. The German thoron progeny chamber-Concept and application

    International Nuclear Information System (INIS)

    Roettger, Annette; Honig, Anja; Arnold, Dirk

    2009-01-01

    Following completion of the project 'Generation and characterisation of reference atmospheres of thoron decay products for the calibration of measuring devices for thoron decay products', the Physikalisch-Technische Bundesanstalt (PTB) now operates a thoron progeny chamber in which 220 Rn (thoron), 222 Rn and its progenies can be made available under almost all ambient conditions. This allows all measuring systems to be calibrated under realistic climatic conditions with an accuracy unique worldwide.

  17. Radon concentration variations between and within buildings of a research institute

    International Nuclear Information System (INIS)

    Antignani, S.; Bochicchio, F.; Ampollini, M.; Venoso, G.; Bruni, B.; Innamorati, S.; Malaguti, L.; Stefano, A.

    2009-01-01

    Radon concentration in indoor air has been measured in many countries in a large number of buildings - mainly in houses but also in apartments and workplaces - mostly as a result of the application of radon policies and regulation requirements. However, few systematic analyses are available on radon concentration variations within buildings and between close buildings, especially as regards workplaces; such variations can have a significant impact on indoor radon exposure evaluation, and ultimately on the assessment of the dose from radon received by workers. Therefore, a project was started in 2006 aimed to study the spatial variation of radon concentration among and within about 40 buildings of the Istituto Superiore di Sanita (ISS), a research institute of public health located in Rome over a small area of less than 1 km 2 . Nuclear track detectors (CR-39) were used to measure radon concentration for two consecutive six-month periods, in more than 700 rooms of the surveyed buildings. The paper describes the project in detail and preliminary results regarding 558 rooms in 29 buildings. Coefficient of variation (CV) was calculated as a measure of relative variation of radon concentration between buildings, between floors, and between rooms on the same floor. The CV between buildings resulted quite high (88%), a lower CV (42%) was found for variation between floors, whereas room-to-room CV on the same floor ranged from 25% at first floor level to 48% at basement level. Floor mean ratios, with ground floor as the reference level, were calculated for each building in order to study the correlation between radon concentration and floor levels. Although no clear trend was observed, the average basement/ground floor ratio of radon concentrations resulted about 2.0, whereas the average sixth floor/ground floor ratio of radon concentrations was 0.5. Some discussion on the potential impact of the results of this study on policies and radon regulations are also included in

  18. DOSEmanPRO - active electronic online personal air sampler for detection of radon progeny long lived alpha nuclides

    International Nuclear Information System (INIS)

    Streil, T.; Oeser, V.

    2002-01-01

    Full text: Using the micro system - technology we developed a online personal air sampler not bigger than a mobile phone, to open a new dimension in personal dosimetry of inhaled radioactive aerosols. The DOSEman PRO containing an internal pump with a continuous air flow of 0.15 I/min sample the radon progeny or other nuclides on a millipore filter with excellent spectroscopic resolution. A 1.5 cm 2 light protected ion-implanted silicon detector analyses the alpha radiation at the filter. This small detector head contains also the pre amplification and pulse processing. The alpha radiation of the radon progeny and the long lived alpha nuclides is analyzed by a 60 channel spectrometer. The energy resolution of the online analyzed filter spectra is in the order of 150 keV. Mechanical and electronic design enables one to distinguish the long lived alpha nuclides from the radon and thoron progeny very easily. Using a special algorithm we correct the influence of the tailing of the radon progeny to the long lived alpha nuclides and take into consideration possible interference in determining the long lived alpha nuclides. Because of the air sampling volume of nearly 10 I/h, the system has a high efficiency. The detection limit by 2 hours sampling time is 0.05 Bq/m 3 alpha nuclide concentration. In a modified device for air sampling especially of long-lived alpha nuclides like uranium, radium or plutonium, the flow rate is increased to 0,3 1/min e.g. during a 10 h sampling period we can detect 0.005 Bq/m 3 in a low radon atmosphere. Assuming increased radon progeny concentration, the statistical error for the long lived alpha nuclides will be higher, but in most of the cases for use in nuclear facilities low radon concentrations are ambient conditions. This concept of an electronic personal air sampler with an alpha spectroscopy offers some outstanding advantages compared to passive dosimeters or off-line alpha air filters: The dose value and the nuclide concentration is

  19. Temporal variations in elemental concentrations of atmospheric aerosols in Mexico City

    International Nuclear Information System (INIS)

    Aldape U, F.

    1992-05-01

    Measurements are reported of elemental concentrations of airborne particulates in Mexico City and their time variation over a one-week period in the spring of 1988. Proton-induced X-ray emission analysis, PIXE, was used to analyse the atmospheric aerosols which were bombarded with 2.5 MeV protons from the 12 MV Tandem Van de Graaff accelerator at the National Institute of Nuclear Research, ININ. Variations in the elemental concentrations were observed over the time period studied. An intercomparison was made in the case of the element lead with PIXE results obtained at the Crocker Nuclear Laboratory, CNL, University of California for the same set of samples. Excellent agreement was obtained both for the time variation of the relative concentration and the absolute lead concentrations. These results give added confidence to the protocol adopted at ININ. (Author)

  20. Attached, unattached fraction of progeny concentrations and equilibrium factor for dose assessments from {sup 222}Rn and {sup 220}Rn

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Parminder; Saini, Komal; Bajwa, Bikramjit Singh [Guru Nanak Dev University, Department of Physics, Amritsar, Punjab (India); Mishra, Rosaline; Sahoo, Bijay Kumar [Bhabha Atomic Research Centre, Radiological Physics and Advisory Division, Mumbai (India)

    2016-08-15

    In this study, measurements of indoor radon ({sup 222}Rn), thoron ({sup 220}Rn) and their equilibrium equivalent concentration (EEC) were carried out in 96 dwellings from 22 different villages situated in Hamirpur district, Himachal Pradesh, India, by using LR-115 type II-based pinhole twin cup dosimeters and deposition-based progeny sensors (DRPS/DTPS). The annual average indoor {sup 222}Rn and {sup 220}Rn concentrations observed in these dwellings were 63.82 and 89.59 Bq/m{sup 3}, respectively, while the average EEC (attached + unattached) for {sup 222}Rn and {sup 220}Rn was 29.28 and 2.74 Bq/m{sup 3}. For {sup 222}Rn (f{sub Rn}) and {sup 220}Rn (f{sub Tn}), the average values of unattached fraction were 0.11 and 0.09, respectively. The equilibrium factors for radon (F{sub Rn}) and thoron (F{sub Tn}) varied from 0.12 to 0.77 with an average of 0.50, and from 0.01 to 0.34 with an average of 0.05, respectively. The annual inhalation dose due to mouth and nasal breathing was calculated using dose conversion factors and unattached fractions. The indoor annual effective doses for {sup 222}Rn (AEDR) and {sup 220}Rn (AEDT) were found to be 1.92 and 0.83 mSv a{sup -1}, respectively. The values of {sup 222}Rn/{sup 220}Rn concentrations and annual effective doses obtained in the present study are within the safe limits as recommended by the International Commission on Radiological Protection for indoor dwelling exposure conditions. (orig.)

  1. Determination of equilibrium factor between radon and its progeny using surface barrier detector for various shapes of passive radon dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Jamil, K. [PINSTECH, Islamabad (Pakistan). Environ. Radiat. Group; Fazal-ur-Rehman [PINSTECH, Islamabad (Pakistan). Environ. Radiat. Group; Ali, S. [PINSTECH, Islamabad (Pakistan). Environ. Radiat. Group; Khan, H.A. [PINSTECH, Islamabad (Pakistan). Environ. Radiat. Group

    1997-03-21

    In the field of radon dosimetry, it is customary to measure radon ({sup 222}Rn) concentration while potential health hazard is due to the radon short-lived progeny. When radon is in secular equilibrium, the measured activity of radon equals the activity of radon`s progeny. However, in practical cases an inequilibrium between radon and its progeny exists which is measured in terms of the equilibrium factor. To determine the equilibrium factor between radon and its progeny in a closed environment various shapes of passive dosimeters based upon solid state nuclear track detectors (SSNTDs) are employed. In order to observe the dependence of equilibrium factor upon shapes or effective volumes, experiments have been performed replacing the SSNTDs with a surface barrier detector in Karlsruhe diffusion chamber, pen-type and box-type dosimeters. Using the collected alpha spectra, the equilibrium factor has been determined for a radon-air mixture in a custom designed radon chamber simulating a closed environment of a room. The results show that the radon equilibrium factor is about 0.20 for different shapes of dosimeters studied in this research. It is concluded that the determination of equilibrium factor between radon and its progeny does not depend upon effective volume or shape of the passive dosimeters using alpha spectroscopic data acquired by surface barrier detector. (orig.).

  2. Determination of equilibrium factor between radon and its progeny using surface barrier detector for various shapes of passive radon dosimeters

    International Nuclear Information System (INIS)

    Jamil, K.; Fazal-ur-Rehman; Ali, S.; Khan, H.A.

    1997-01-01

    In the field of radon dosimetry, it is customary to measure radon ( 222 Rn) concentration while potential health hazard is due to the radon short-lived progeny. When radon is in secular equilibrium, the measured activity of radon equals the activity of radon's progeny. However, in practical cases an inequilibrium between radon and its progeny exists which is measured in terms of the equilibrium factor. To determine the equilibrium factor between radon and its progeny in a closed environment various shapes of passive dosimeters based upon solid state nuclear track detectors (SSNTDs) are employed. In order to observe the dependence of equilibrium factor upon shapes or effective volumes, experiments have been performed replacing the SSNTDs with a surface barrier detector in Karlsruhe diffusion chamber, pen-type and box-type dosimeters. Using the collected alpha spectra, the equilibrium factor has been determined for a radon-air mixture in a custom designed radon chamber simulating a closed environment of a room. The results show that the radon equilibrium factor is about 0.20 for different shapes of dosimeters studied in this research. It is concluded that the determination of equilibrium factor between radon and its progeny does not depend upon effective volume or shape of the passive dosimeters using alpha spectroscopic data acquired by surface barrier detector. (orig.)

  3. Estimation of radiological dose from radon, thoron and their progeny levels in the dwellings of Shivamogga district, Karnataka, India

    International Nuclear Information System (INIS)

    Rangaswamvi, D.R.; Sannappa, J.; Srinivasa, E.

    2018-01-01

    Among all natural radiation exposure to man, inhalation of radon, thoron and their progenies are the major contributor (50 %) to the dose from ionizing radiation received by the general population. Based on the results of epidemiological studies in Europe and North America, the World Health Organization (WHO) has recommended reducing the indoor radon reference level from 200 to 100 Bq.m -3 . In view of this, focus has now been given for simultaneous measurement of radon, thoron and their progeny concentration in indoor air and also to estimate radiological dose in the dwellings of the Shivamogga district. The geology of the Shivamogga district comprises different types of rock formation such as granites, schists, magnetites and gneisses, Meta basalt, laterites, quartz and chlorite schist, Graywacke etc. Present study was concentrating more in granite bed rock regions along with their surrounding regions

  4. A method for determining an indicator of effective dose calculation due to inhalation of Radon and its progeny from in vivo measurements; Um metodo para determinar um indicador para calcular dose efetiva devida a inalacao de Radonio e seus descendentes utilizando medicoes in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Estrada, Julio Jose da Silva

    1994-07-01

    Direct measurement of the absolved dose to lung tissue from inhalation of radon and its progeny is not possible and must be calculated using dosimetric models, taking into consideration the several parameters upon which the dose calculation depends. To asses the dose due to inhalation of radon and its progeny, it is necessary to estimate the cumulative exposure. Historically, this has been done using WLM values estimated with measurements of radon concentration in air. The radon concentration in air varies significantly, however, in space with time, and the exposed individual is also constantly moving around. This makes it almost impossible to obtain a precise estimate of an individual's inhalation exposure. This work describes a pilot study to calculate lung dose from the deposition of radon progeny, via estimates of cumulative exposure derived from in vivo measurements of {sup 210} Pb, in subjects exposed to above-average radon and its progeny concentrations in their home environments. The measurements were performed in a whole body counter. With this technique, the exposed individuals become, in affect, their own samplers and dosimeters and the estimate of cumulative exposure is not affected by the variation of the atmospheric concentration of radon and its progeny in time and space. Forty individuals identified as living in homes with radon levels ranging from about 740 Bq/m{sup 3} to 150.000 Bq/m{sup 3} were measured. Also, additional 34 measurements were made on personnel from NYUMC/NIEM who live in a residential area surrounding the laboratory in which the levels of radon have been shown to be at below average values. To realize these measurements a methodology was developed to determine the subject's background, using a head phantom made with a cubic plastic container containing known amounts of potassium and calcium dissolved in four liters of water. The effective doses calculated from the in vivo measurements are compared to effective doses estimated, for

  5. A method for determining an indicator of effective dose calculation due to inhalation of Radon and its progeny from in vivo measurements; Um metodo para determinar um indicador para calcular dose efetiva devida a inalacao de Radonio e seus descendentes utilizando medicoes in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Estrada, Julio Jose da Silva

    1994-07-01

    Direct measurement of the absolved dose to lung tissue from inhalation of radon and its progeny is not possible and must be calculated using dosimetric models, taking into consideration the several parameters upon which the dose calculation depends. To asses the dose due to inhalation of radon and its progeny, it is necessary to estimate the cumulative exposure. Historically, this has been done using WLM values estimated with measurements of radon concentration in air. The radon concentration in air varies significantly, however, in space with time, and the exposed individual is also constantly moving around. This makes it almost impossible to obtain a precise estimate of an individual's inhalation exposure. This work describes a pilot study to calculate lung dose from the deposition of radon progeny, via estimates of cumulative exposure derived from in vivo measurements of {sup 210} Pb, in subjects exposed to above-average radon and its progeny concentrations in their home environments. The measurements were performed in a whole body counter. With this technique, the exposed individuals become, in affect, their own samplers and dosimeters and the estimate of cumulative exposure is not affected by the variation of the atmospheric concentration of radon and its progeny in time and space. Forty individuals identified as living in homes with radon levels ranging from about 740 Bq/m{sup 3} to 150.000 Bq/m{sup 3} were measured. Also, additional 34 measurements were made on personnel from NYUMC/NIEM who live in a residential area surrounding the laboratory in which the levels of radon have been shown to be at below average values. To realize these measurements a methodology was developed to determine the subject's background, using a head phantom made with a cubic plastic container containing known amounts of potassium and calcium dissolved in four liters of water. The effective doses calculated from the in vivo measurements are compared to effective doses

  6. Secular variation of cosmic ray intensity recorded in the radiocarbon concentration of tree rings

    International Nuclear Information System (INIS)

    Kigoshi, K.

    1978-01-01

    Study of the secular variations of cosmic ray intensity on the basis of the secular variations of atmospheric radiocarbon concentration in 8000 years is considered. The data on the radiocarbon concentration is received by three laboratories using the dendrochronologically dated tree ring samples. In order to use the data the variations due to geochemical process must be eliminated. From this point of view the climatic effect on the atmospheric radiocarbon concenttration is estimated using the data on sunspot number and global surface temperature during 1650-1800 y. The barge influence of climate on the atmospheric radiocarbon concentration syggests the small contribution of change of radiocarbon production rate to the short-period fluctuations in the atmospheric radiocarbon concentration. Elimination of variations caused by climate and sunspot activities from the variations in atmospheric radiocarbon concentration gives a long-term scale of its concentration which agrees well to the observed paleo-geomagnetic data

  7. All eggs are not equal: the maternal environment affects progeny reproduction and developmental fate in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Simon C Harvey

    Full Text Available Maternal effects on progeny traits are common and these can profoundly alter progeny life history. Maternal effects can be adaptive, representing attempts to appropriately match offspring phenotype to the expected environment and are often mediated via trade-offs between progeny number and quality. Here we have investigated the effect of maternal food availability on progeny life history in the free-living nematode Caenorhabditis elegans.The maternal environment affects both reproductive traits and progeny development. Comparisons of the progeny of worms from high and low maternal food environments indicates that low maternal food availability reduces progeny reproduction in good environments, increases progeny reproduction in poor environments and decreases the likelihood that progeny will develop as dauer larvae. These analyses also indicate that the effects on progeny are not a simple consequence of changes in maternal body size, but are associated with an increase in the size of eggs produced by worms at low maternal food availabilities.These results indicate that the maternal environment affects both progeny reproduction and development in C. elegans and therefore that all progeny are not equal. The observed effects are consistent with changes to egg provisioning, which are beneficial in harsh environments, and of changes to progeny development, which are beneficial in harsh environments and detrimental in benign environments. These changes in progeny life history suggest that mothers in poor quality environments may be producing larger eggs that are better suited to poor conditions.

  8. Underground measurements of aerosol in radon and thoron progeny activity distributions

    International Nuclear Information System (INIS)

    Khan, A.; Bandi, F.; Phillips, C.R.; Duport, P.

    1990-01-01

    Aerosol and activity distributions of 218 Polonium, 214 Lead, 214 Bismuth, and 212 Lead were determined in two different underground mining environments by means of an optimized time-delay counting scheme and diffusion batteries. In one environment, diesel equipment was operating; and in the other, electrically powered equipment. The two environments differed significantly in total aerosol concentration. In the diesel environment, in particular, aerosol concentrations were unsteady, and fluctuated with vehicular traffic and mining activities. As measured by radon progeny disequilibrium, the age of the air ranged from about 25 to 60 minutes. Thoron working levels were of the same order as radon working levels. In this paper, comparisons are made between the aerosol and activity size distributions in both the diesel and electric mine

  9. Sex ratio variation and sex determination in Urtica dioica

    NARCIS (Netherlands)

    Glawe, Grit Anja

    2006-01-01

    This thesis will first document on variation in progeny sex ratios among individual female plants of Urtica dioica at our field site in Meijendel (Chapter 2). Next, we show that there is also considerable sex ratio variation among male and female flowering shoots in 26 natural populations studied

  10. Genetic Diversity and Relationships of Neolamarckia cadamba (Roxb. Bosser progenies through cluster analysis

    Directory of Open Access Journals (Sweden)

    M. Preethi Shree

    2018-04-01

    Full Text Available Genetic diversity analysis was conducted for biometric attributes in 20 progenies of Neolamarckia cadamba. The application of D2 clustering technique in Neolamarckia cadamba genetic resources resolved the 20 progenies into five clusters. The maximum intra cluster distance was shown by the cluster II. The maximum inter cluster distance was recorded between cluster III and V which indicated the presence of wider genetic distance between Neolamarckia cadamba progenies. Among the growth attributes, volume (36.84 % contributed maximum towards genetic divergence followed by bole height, basal diameter, tree height, number of branches in Neolamarckia cadamba progenies.

  11. Effect of calving distribution on beef cattle progeny performance.

    Science.gov (United States)

    Funston, R N; Musgrave, J A; Meyer, T L; Larson, D M

    2012-12-01

    Records collected between 1997 and 2010 were used to determine the effect of calving period on heifer (n = 1,019) and steer (n = 771) progeny from the Gudmundsen Sandhills Laboratory, Whitman, NE. Progeny were classified as being born in the first, second, or third 21-d period of the spring calving season within year. Heifer birth BW was lightest (P Birth to weaning ADG tended (P = 0.10) to be least for heifers born in the first calving period; however, weaning BW decreased (P = 0.03) with advancing calving period. Weaning to prebreeding ADG tended (P = 0.07) to be least for heifers born in the first period; however, prebreeding BW was greatest (P rates were lowest (P = 0.02) for heifers born in the third calving period (90, 86, and 78%, respectively). Birth date of the first calf of the heifer and birth BW decreased (P rates compared with heifers born in the third period. First calf progeny also had an earlier birth date and greater weaning BW. Steer calves born during the first 21 d of the calving season had greater weaning, final, and carcass weights; greater marbling scores; a greater percentage grading USDA modest or greater; and greater carcass value. Calving period of progeny significantly impacts performance.

  12. Radionuclide supply of the progeny via mother's milk

    International Nuclear Information System (INIS)

    Ovcharenko, E.P.

    1982-01-01

    While examining transition of radioactive substances from material organism to milk and then radionuclide administration with milk to progeny, a number of relationships had been revealed. They are similar to those discovered by the author during his study on transplacental radionuclide kinetics. The quantity of transition through placental and milk barriers of group 2 Periodical system radionuclides is inversally proportional to radionuclide mass number. There is evidence for the increase of radionuclide transition per different kinds of animal progeny mass unit during pregnancy as well as during lactation [ru

  13. Variation of Potential Yield of Hybrid Population of Robusta coffee (Coffea canepor

    Directory of Open Access Journals (Sweden)

    Novie Pranata Erdiansyah

    2014-08-01

    Full Text Available The low yield of Robusta coffee in Indonesia may be due to the use of planting materials derived from seeds. The research objective was to determine the variation of Robusta coffee yield wich local propagated by using seeds. The study was conducted in Kaliwining experimental Station of ICCRI (Indonesian Coffee andCocoa Research Institute. There were two populations observed. Number of progeny used in this study were 186 genotypes consisting of two groups from crossesBP 409 x Q 121 with 89 progenies and BP 961 x BP 409 with 81 progenies. The results showed that planting materials from seeds exhibit properties mixed results.Progeny that have the best results (yield more than 2 ton/ha not more than 5% of the total population. In both populations there is a big difference between the progenythat has high and low yield. Highest yield B population could reach 2,500 kg/ha and the C population reached 2,200 kg/ha. The lowest yield can only produce coffee270 kg/ha in populations B and 120 kg/ha in population C.Key words: Coffea canephora, hybrid, variation, yield

  14. Estimation of radon progeny equilibrium factors and their uncertainty bounds using solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Eappen, K.P.; Mayya, Y.S.; Patnaik, R.L.; Kushwaha, H.S.

    2006-01-01

    For the assessment of inhalation doses due to radon and its progeny to uranium mine workers, it is necessary to have information on the time integrated gas concentrations and equilibrium factors. Passive single cup dosimeters using solid state nuclear track detectors (SSNTD) are best suited for this purpose. These generally contain two SSNTDs, one placed inside the cup to measure only the radon gas concentration and other outside the cup for recording tracks due to both radon gas and the progeny species. However, since one obtains only two numbers by this method whereas information on four quantities is required for an unambiguous estimation of dose, there is a need for developing an optimal methodology for extracting information on the equilibrium factors. Several techniques proposed earlier have essentially been based on deterministic approaches, which do not fully take into account all the possible uncertainties in the environmental parameters. Keeping this in view, a simple 'mean of bounds' methodology is proposed to extract equilibrium factors based on their absolute bounds and the associated uncertainties as obtained from general arguments of radon progeny disequilibrium. This may be considered as reasonable estimates of the equilibrium factors in the absence of a knowledge of fluctuation in the environmental variables. The results are compared with those from direct measurements both in the laboratory and in real field situations. In view of the good agreement found between these, it is proposed that the simple mean of bounds estimate may be useful for practical applications in inhalation dosimetry of mine workers

  15. Prediction of direct and indirect genetic gains and genotypic correlations in rubber tree progenies

    Directory of Open Access Journals (Sweden)

    Cecília Khusala Verardi

    2011-09-01

    Full Text Available The objective of this work was to estimate the genetic parameters, genotypic and phenotypic correlations, and direct and indirect genetic gains among and within rubber tree (Hevea brasiliensis progenies. The experiment was set up at the Municipality of Jaú, SP, Brazil. A randomized complete block design was used, with 22 treatments (progenies, 6 replicates, and 10 plants per plot at a spacing of 3x3 m. Three‑year‑old progenies were assessed for girth, rubber yield, and bark thickness by direct and indirect gains and genotypic correlations. The number of latex vessel rings showed the best correlations, correlating positively and significantly with girth and bark thickness. Selection gains among progenies were greater than within progeny for all the variables analyzed. Total gains obtained were high, especially for girth increase and rubber yield, which were 93.38 and 105.95%, respectively. Young progeny selection can maximize the expected genetic gains, reducing the rubber tree selection cycle.

  16. Genetic Divergence in Eucalyptus camaldulensis Progenies in the Savanna Biome in Mato Grosso, Brazil.

    Directory of Open Access Journals (Sweden)

    Reginaldo Brito da Costa

    Full Text Available Assessing the parental genetic differences and their subsequent prediction of progeny performance is an important first step to assure the efficiency of any breeding program. In this study, we estimate the genetic divergence in Eucalyptus camaldulensis based on the morphological traits of 132 progenies grown in a savanna biome. Thus, a field experiment was performed using a randomized block design and five replications to compare divergences in total height, commercial height, diameter at breast height, stem form and survival rate at 48 months. Tocher's clustering method was performed using the Mahalanobis and Euclidian distances. The Mahalanobis distance seemed more reliable for the assessed parameters and clustered all of the progenies into fourteen major groups. The most similar progenies (86 accessions were clustered into Group I, while the most dissimilar (1 progeny represented Group XIV. The divergence analysis indicated that promising crosses could be made between progenies allocated in different groups for high genetic divergence and for favorable morphological traits.

  17. Absence of diurnal variation of C-reactive protein concentrations in healthy human subjects

    Science.gov (United States)

    Meier-Ewert, H. K.; Ridker, P. M.; Rifai, N.; Price, N.; Dinges, D. F.; Mullington, J. M.

    2001-01-01

    BACKGROUND: The concentration of C-reactive protein (CRP) in otherwise healthy subjects has been shown to predict future risk of myocardial infarction and stroke. CRP is synthesized by the liver in response to interleukin-6, the serum concentration of which is subject to diurnal variation. METHODS: To examine the existence of a time-of-day effect for baseline CRP values, we determined CRP concentrations in hourly blood samples drawn from healthy subjects (10 males, 3 females; age range, 21-35 years) during a baseline day in a controlled environment (8 h of nighttime sleep). RESULTS: Overall CRP concentrations were low, with only three subjects having CRP concentrations >2 mg/L. Comparison of raw data showed stability of CRP concentrations throughout the 24 h studied. When compared with cutoff values of CRP quintile derived from population-based studies, misclassification of greater than one quintile did not occur as a result of diurnal variation in any of the subjects studied. Nonparametric ANOVA comparing different time points showed no significant differences for both raw and z-transformed data. Analysis for rhythmic diurnal variation using a method fitting a cosine curve to the group data was negative. CONCLUSIONS: Our data show that baseline CRP concentrations are not subject to time-of-day variation and thus help to explain why CRP concentrations are a better predictor of vascular risk than interleukin-6. Determination of CRP for cardiovascular risk prediction may be performed without concern for diurnal variation.

  18. Portable devices for monitoring radon and its progeny in air

    International Nuclear Information System (INIS)

    Zhang Huaiqin; Yao Wanyuan; Su Jingling; Liu Jinhua

    1990-01-01

    We have developed two kinds of portable monitoring devices to measure the concentration and potential energy concentration of radon and its progeny in air. The thermoluminescence material CaSO4 (Tm) is used as the detection element. One of the devices is called passive radon monitor. The lowest detectable limit for radon in air is about 1.5 Bq/m 3 , as a sampling time being one week. Good reliability and ease to operate are its main advantages. The second kind of device is called a working level monitor which consists of a miniature remembrane pump and an integrating sampling probe. The lowest detectable limit is about 0.00043 WL (9x10 -9 J/m 3 ) for a sampling time of 6 hours. It weighs only 0.35 kg, but maintenance is necessary sometimes. (author). 6 refs, 2 figs, 4 tabs

  19. Examination of the influence of water-heated central heating systems on the levels of radon and radon progeny in the workplace

    International Nuclear Information System (INIS)

    Marley, F.; Denman, A.R.; Phillips, P.S.

    2000-01-01

    A series of continuous real-time radon and progeny measurements, together with passive etched-track detector measurements returning average values, were undertaken in commercial premises in Northamptonshire. Detailed measurements over several months in two separate buildings show that the level of both radon and progeny are determined to a major extent by the influence of the operation and timing of the central heating systems in place. Both buildings studied are similar in construction to many single-storey domestic properties. The operative heating system reduced the radon and progeny levels relative to the non-operating mode by over 40% during the heating period of a normal working day. The variation in temperature during this time was generally less than 3 deg. C, indicative of a heat retentive building. Because the equilibrium (F) fraction is reduced during the heating period, the reductions in radon and progeny are not uniform. In the workplaces studied, the work-cycle was normally limited to 0900-1700 hours Monday to Friday, the period when the lowest values were recorded. Average daily values would therefore overstate by more than 50% the maximum potential dose during normal attendance hours. The corollary is that living under similar circumstances in domestic environments, the operation and timing of this type of heating regime may well result in higher exposure in the home than at work

  20. Factors affecting yearly variations of indoor radon concentrations

    International Nuclear Information System (INIS)

    Steck, D.J.; Baynes, S.A.

    1996-01-01

    Since indoor radon exposures take place over many years while radon measurement periods are shorter, we are studying the yearly variation of indoor radon concentrations in approximately 100 houses located throughout Minnesota. Most houses were initially measured for one or more years in the late 1980's and for 5 consecutive years starting in 1990. Two houses have been monitored for 12 y. Each year, two alpha track detectors were placed on the two lowest livable levels. The year-to-year variations averaged about 35% (corrected for instrumental uncertainties) in both basements and first floors. The minimum observed variation was 5% and the maximum was 130%. Some homes have shown substantial variation associated with Structural modifications. While most homes show no obvious systematic trends, a few houses have shown temporal trends that may be associated with aging or climate. We are studying possible correlation between year-to-year radon variation, climatic variables (yearly-average and seasonal such as heating/cooling degree days, precipitation, soil moisture), and structural changes

  1. Measurment of radon, thoron and their progeny in indoor environment of Mohali, Punjab, Northern India, using pinhole dosimeters

    Directory of Open Access Journals (Sweden)

    Mehta Vimal

    2016-01-01

    Full Text Available The health hazards of radon and its decay products above certain levels are well known. However, for any preventive measures to be taken, we have to be aware of radon levels of that particular area. Measurement of radon and its decay products in indoor environments is an important aspect of assessing indoor air quality and health conditions associated with it. Keeping this in mind, measurements of radon, thoron and their progeny concentrations were carried out in Mohali, Northern India, using pinhole-based twin cup dosimeters. Radon exhalation rates of soil samples in the dwellings/areas were measured via an active technique of a continuous radon monitor. The indoor radon concentration in Mohali varied from 15.03 ± 0.61 Bq/m3 to 39.21 ± 1.46 Bq/m3 with an average of 26.95 Bq/m3 ,while thoron concentration in the same dwellings varied from 9.62 ± 0.54 Bq/m3 to 52.84 ± 2.77 Bq/m3 with an average of 31.09 Bq/m3. Radon progeny levels in dwellings under study varied from 1.63 to 4.24 mWL, with an average of 2.94 mWL, while thoron progeny levels varied from 0.26 to 1.43 mWL , with an average of 0.84 mWL. The annual dose received by the inhabitants of dwellings under study varied from 0.78 to 2.36 mSv, with an average of 1.61 mSv. The in situ gamma dose rate varied from 0.12 to 0.32 mSv/h.

  2. Detection of atmospheric tritium by scintillation. Variations in its concentration in France

    International Nuclear Information System (INIS)

    Bibron, R.

    1964-06-01

    The tritium released into the atmosphere as a result of the explosion of thermonuclear devices is a useful radioactive tracer for the study of certain geophysical problems. The low concentrations found however call for the use of extremely sensitive detectors. Two detection methods using liquid scintillators are described. In the first method, the sample is introduced into the scintillator in liquid form, after prior concentration of the tritium by electrolysis. In the second method the tritium is incorporated into the scintillator solvent molecule by chemical synthesis. In the last part of the report are examined the variations in the tritium concentration in rain-water and of the free hydrogen in the air in France. A discussion is then made of the seasonal variations in the case of rain-water and these are compared to the variations in the strontium-90 concentrations. (author) [fr

  3. Microdosimetry of radon progeny: Application to risk assessment

    International Nuclear Information System (INIS)

    Fisher, D.R.; Hui, T.E.; James, A.C.; Bond, V.P.

    1990-01-01

    We developed methods for calculating radiation doses to individual cells and cell nuclei of human bronchial epithelium from radon and progeny for specified levels of exposure, breathing rates, equilibrium factors, unattached fraction of progeny, and other factors that are important in radon dosimetry. If we also know which cells are likely precursors for cancer, and we also know their locations in the respiratory tract, we then may calculate the statistical probability that these cells are irradiated by alpha particles, the number of single alpha-particle hits, and the spectrum of doses delivered as a probability density in specific energy

  4. Exposure of workers to radon progeny in the Baradla cave at Aggtelek

    International Nuclear Information System (INIS)

    Dezsoe, Z.

    2004-01-01

    By measuring the radon concentration using active technique in all parts of the cave visited in a tour and furthermore by assessing also the time spent at these locations, it is possible to determine the radon level averaged over a tour. The time averaged radon concentration along the route of the cave investigated has been estimated to 970 Bq/m 3 in summer and 410 Bq/m 3 in winter. We concluded that in 62 % of the year cave climate shows warm season and only in 38 % cold season Rn-levels. On this basis the yearly mean radon concentration averaged over the tour comes to 750 Bq/m3. This figure, however, should not be used to estimate exposure because the number of visitors is substantially higher in summer than in winter, so that the tour guides work much more in summer (about 750 tours) than in winter (about 270 tours). Taking this into account, the yearly mean Rn concentration is to 820 Bq/m 3 . Since the dose is delivered by radon progeny and not radon itself, one has to also assess the equilibrium factor representative in the cave. The data available in the literature show that F is always larger than under normal ambient conditions. Published values are between 0.5 - 0.8. As part of this work, several radon progeny concentration measurements have also been made in the Baradla cave at different locations. The results confirm the occurrence of high F-values in caves. Furthermore, the equilibrium factor is increased by the presence of humans (visitors or cavers). In the Virgin Cave, F = 0.5 - 0.6, which increases steadily to about 0.8 due to the activity of man. In this work, F = 0.8 has been used for the dose assessment. Using the ICRP 65 dosimetry model, exposure was calculated to be 4.04 mJhm 3 , which corresponds to an effective dose of 5.8 mSv. (P.A.)

  5. Intercomparison of active, passive and continuous instruments for radon and radon progeny measurements in the EML chamber and test facility

    International Nuclear Information System (INIS)

    Scarpitta, S.C.; Tu, K.W.; Fisenne, I.M.; Cavallo, A.; Perry, P.

    1996-10-01

    Results are presented from the Fifth Intercomparison of Active, Passive and Continuous Instruments for Radon and Radon Progeny Measurements conducted in the EML radon exposure and test facility in May 1996. In total, thirty-four government, private and academic facilities participated in the exercise with over 170 passive and electronic devices exposed in the EML test chamber. During the first week of the exercise, passive and continuous measuring devices were exposed (usually in quadruplicate) to about 1,280 Bq m -3 222 Rn for 1--7 days. Radon progeny measurements were made during the second week of the exercise. The results indicate that all of the tested devices that measure radon gas performed well and fulfill their intended purpose. The grand mean (GM) ratio of the participants' reported values to the EML values, for all four radon device categories, was 0.99 ± 0.08. Eighty-five percent of all the radon measuring devices that were exposed in the EML radon test chamber were within ±1 standard deviation (SD) of the EML reference values. For the most part, radon progeny measurements were also quite good as compared to the EML values. The GM ratio for the 10 continuous PAEC instruments was 0.90 ± 0.12 with 75% of the devices within 1 SD of the EML reference values. Most of the continuous and integrating electronic instruments used for measuring the PAEC underestimated the EML values by about 10--15% probably because the concentration of particles onto which the radon progeny were attached was low (1,200--3,800 particles cm -3 ). The equilibrium factor at that particle concentration level was 0.10--0.22

  6. Long-term variation of outdoor radon equilibrium equivalent concentration

    Energy Technology Data Exchange (ETDEWEB)

    Hoetzl, H. [GSF-Forschungszentrum fuer Umwelt und Gesundheit, Inst. fuer Strahlenschutz, Oberschleissheim (Germany); Winkler, R. [GSF-Forschungszentrum fuer Umwelt und Gesundheit, Inst. fuer Strahlenschutz, Oberschleissheim (Germany)

    1994-10-01

    Long-term variation of outdoor radon equilibrium equivalent concentration was investigated from 1982 to 1992 at a semi-natural location 10 km north of Munich, southern Germany. For this period the continuous measurement yielded a long-term average of 8.6 Bq.m{sup -3} (arithmetic mean) and 6.9 Bq.m{sup -3} (geometric mean), from which an average annual effective dose of 0.14 mSv due to outdoor radon can be derived. A long-term trend of the radon concentration was not detectable over the whole period of observation. However, by time series analysis, a long-term cyclic pattern was identified with two maxima (1984-1986, 1989-1991) and two minima (1982-1983, 1987-1988). The seasonal pattern is characterized by an autumn maximum and an early summer minimum. On average, the seasonal maximum in October was found to be higher by a factor of 2 than the June minimum. The diurnal variation of the radon concentration shows a maximum in the early morning and a minimum in the afternoon. On average, this maximum is a factor of 2 higher than the minimum. In the long term a seasonal pattern was observed for diurnal variation, with an average diurnal maximum to minimum ratio of 1.5 in winter compared with 3.5 in the summer months. The radon concentration is correlated with a meteorological parameter (stagnation index) which takes into account horizontal and vertical exchange processes and the wash-out of aerosols in the lower atmosphere. (orig.)

  7. Long-term variation of outdoor radon equilibrium equivalent concentration

    International Nuclear Information System (INIS)

    Hoetzl, H.; Winkler, R.

    1994-01-01

    Long-term variation of outdoor radon equilibrium equivalent concentration was investigated from 1982 to 1992 at a semi-natural location 10 km north of Munich, southern Germany. For this period the continuous measurement yielded a long-term average of 8.6 Bq.m -3 (arithmetic mean) and 6.9 Bq.m -3 (geometric mean), from which an average annual effective dose of 0.14 mSv due to outdoor radon can be derived. A long-term trend of the radon concentration was not detectable over the whole period of observation. However, by time series analysis, a long-term cyclic pattern was identified with two maxima (1984-1986, 1989-1991) and two minima (1982-1983, 1987-1988). The seasonal pattern is characterized by an autumn maximum and an early summer minimum. On average, the seasonal maximum in October was found to be higher by a factor of 2 than the June minimum. The diurnal variation of the radon concentration shows a maximum in the early morning and a minimum in the afternoon. On average, this maximum is a factor of 2 higher than the minimum. In the long term a seasonal pattern was observed for diurnal variation, with an average diurnal maximum to minimum ratio of 1.5 in winter compared with 3.5 in the summer months. The radon concentration is correlated with a meteorological parameter (stagnation index) which takes into account horizontal and vertical exchange processes and the wash-out of aerosols in the lower atmosphere. (orig.)

  8. Morphometric and functional abnormalities of kidneys in the progeny of mice fed chocolate during pregnancy and lactation.

    Directory of Open Access Journals (Sweden)

    Ewa Skopińska-Rózewska

    2006-09-01

    Full Text Available Even most commonly consumed beverages like tea, coffee, chocolate and cocoa contain methylxanthines, biogenic amines and polyphenols, among them catechins, that exhibit significant biological activity and might profoundly affect the organism homeostasis. We have previously shown that 400 mg of bitter chocolate or 6 mg of theobromine added to the daily diet of pregnant and afterwards lactating mice affected embryonic angiogenesis and caused bone mineralization disturbances as well as limb shortening in 4-weeks old offspring. The aim of the present study was the morphometric and functional evaluation of kidneys in the 4-weeks old progeny mice fed according to the protocol mentioned above. Progeny from the mice fed chocolate presented considerable morphometric abnormalities in the kidney structure, with the lower number of glomeruli per mm2 and their increased diameter. Moreover, higher serum creatinine concentration was observed in that group of offspring. No morphometric or functional irregularities were found in the progeny of mice fed theobromine. Abnormalities demonstrated in the offspring of mice fed chocolate are not related to its theobromine content. Consequently, identification of active compound(s responsible for the observed effects is of vital importance.

  9. Leukemias in the progeny of exposed parents

    International Nuclear Information System (INIS)

    Kosenko, M.M.; Gudkova, N.V.

    1996-01-01

    The purpose of this study was to assess the incidence of leukemias among the progeny of exposed parents. The parents were exposed as a result of discharge of radioactive waste from the Mayak atomic plant into the Techa river in the Southern Urals. The doses per parents gonads, ranging from 0.035 to 1.27 Sv, were due to external exposure in 1950-1956 and to incorporation of Cs-137. Nine cases with leukemia and four with lympohoma were recorded in 13.500 antenatally exposed subjects and descendants of exposed parents over the period of 1950 to 1988. The leukemia morbidity index for the progeny of exposed parents was 2.51, which virtually not statistically differ from that in control group. Refs. 7, figs. 3, tabs. 3

  10. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres. Final project report

    International Nuclear Information System (INIS)

    Hopke, P.K.

    1996-09-01

    This report completes Clarkson University's study of the chemical and physical behavior of the 218 Po atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity in the sub-10 nm size range result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and it dose to the cells in the respiratory tract are to be fully assessed. In order to pursue this general goal, two areas of radon progeny behavior are being pursued; laboratory studies under controlled conditions to better understand the fundamental physical and chemical processes that affect the progeny's atmospheric behavior and studies in actual indoor environments to develop a better assessment of the exposure of the occupants of that space to the size and concentration of the indoor radioactive aerosol. Thus, two sets of specific goals have been established for this project. The specific tasks of the controlled laboratory studies are (1) Determine the formation rates of circ OH radicals formed by the radiolysis of air following radon decay; (2) Examine the formation of particles by the radiolytic oxidation of substances like SO 2 , ethylene, and H 2 S to lower vapor pressure compounds and determine the role of gas phase additives such as H 2 O and NH 3 in determining the particle size; (3) Measure the rate of ion-induced nucleation using a thermal diffusion cloud chamber, and (4) Measure the neutralization rate of 218 PoO x + in O 2 at low radon concentrations

  11. Progeny Clustering: A Method to Identify Biological Phenotypes

    Science.gov (United States)

    Hu, Chenyue W.; Kornblau, Steven M.; Slater, John H.; Qutub, Amina A.

    2015-01-01

    Estimating the optimal number of clusters is a major challenge in applying cluster analysis to any type of dataset, especially to biomedical datasets, which are high-dimensional and complex. Here, we introduce an improved method, Progeny Clustering, which is stability-based and exceptionally efficient in computing, to find the ideal number of clusters. The algorithm employs a novel Progeny Sampling method to reconstruct cluster identity, a co-occurrence probability matrix to assess the clustering stability, and a set of reference datasets to overcome inherent biases in the algorithm and data space. Our method was shown successful and robust when applied to two synthetic datasets (datasets of two-dimensions and ten-dimensions containing eight dimensions of pure noise), two standard biological datasets (the Iris dataset and Rat CNS dataset) and two biological datasets (a cell phenotype dataset and an acute myeloid leukemia (AML) reverse phase protein array (RPPA) dataset). Progeny Clustering outperformed some popular clustering evaluation methods in the ten-dimensional synthetic dataset as well as in the cell phenotype dataset, and it was the only method that successfully discovered clinically meaningful patient groupings in the AML RPPA dataset. PMID:26267476

  12. Radon concentration and working level in the Exploratory Studies Facility (ESF)

    International Nuclear Information System (INIS)

    Stiver, J.H.; Tung, Chao-Hsiung.

    1995-01-01

    Radon-222 ( 222 Rn) and 222 Rn progeny WL monitoring in the Exploratory Studies Facility (ESF) was initiated to support regulatory compliance. Measurements were taken over two periods, in Test Alcove No. 1 of the ESF, about 60 m from the tunnel entrance. For both periods, 222 Rn concentration was less than 10% of the Derived Air Concentration (DAC) set forth in DOE Order 5480.11. Thus, these assessments were sufficient to demonstrate regulatory compliance. Based on these findings, quarterly 222 Rn and 222 Rn progeny monitoring was initiated. Two systems each were employed for 222 Rn and 222 Rn progeny measurement. No significant differences were observed between the respective systems. An interesting finding was that at the time the measurements were taken, barometric pressure appeared to be the predominant factor controlling 222 Rn concentration in the ESF. This was true even during periods of ventilation shutdown

  13. Traceable measurements of the activity concentration in air

    International Nuclear Information System (INIS)

    Paul, Annette; Honig, Anja; Forkel-Wirth, Doris; Mueller, Andre; Marcos, Alicia

    2002-01-01

    The nuclear reactions induced by high energetic protons in heavy targets such as UC 2 and ThC cause a particular, complex radiation protection task at facilities like ISOLDE: the measurement of a mixture of different isotopes of the radioactive noble gas radon and the radon progenies in air. The knowledge of their respective activity concentration is fundamental for exposure assessments. Due to the complex mixture of activity concentrations in air, its precise determination is quite difficult. Therefore, a new procedure for taking reference samples was developed and implemented for the traceable measurement of the activity concentration of radioactive ions (e.g., radon progenies) in air. This technique is combined by measuring α-particles with a multi-wire ionization chamber for the parallel on-line determination of the activity concentration of different radon isotopes

  14. Wire-mesh capped deposition sensors: Novel passive tool for coarse fraction flux estimation of radon thoron progeny in indoor environments

    International Nuclear Information System (INIS)

    Mayya, Y.S.; Mishra, Rosaline; Prajith, Rama; Sapra, B.K.; Kushwaha, H.S.

    2010-01-01

    Deposition-based 222 Rn and 220 Rn progeny sensors act as unique, passive tools for determining the long time-averaged progeny deposition fluxes in the environment. The use of these deposition sensors as progeny concentration monitors was demonstrated in typical indoor environments as conceptually superior alternatives to gas-based indirect monitoring methods. In the present work, the dependency of these deposition monitors on various environmental parameters is minimized by capping the deposition sensor with a suitable wire mesh. These wire-mesh capped deposition sensors measure the coarse fraction deposition flux, which is less dependent on the change in environmental parameters like ventilation rate and turbulence. The calibration of these wire-mesh capped coarse fraction progeny sensors was carried out by laboratory controlled experiments. These sensors were deployed both in indoor and in occupational environments having widely different ventilation rates. The obtained coarse fraction deposition velocities were fairly constant in these environments, which further confirmed that the signal on the wire-mesh capped sensors show the least dependency on the change in environmental parameters. This technique has the potential to serve as a passive particle sizer in the general context of nanoparticles using progeny species as surrogates. On the whole, there exists a strong case for developing a passive system that responds only to coarse fraction for providing alternative tools for dosimetry and environmental fine particle research. - Research highlights: → Wire-mesh capped deposition sensor measures the coarse fraction deposition flux → Coarse fraction deposition flux less dependent on environmental conditions → Wire-mesh capped deposition sensor as passive particle sizer

  15. Maternal Diet and Insulin-Like Signaling Control Intergenerational Plasticity of Progeny Size and Starvation Resistance.

    Directory of Open Access Journals (Sweden)

    Jonathan D Hibshman

    2016-10-01

    Full Text Available Maternal effects of environmental conditions produce intergenerational phenotypic plasticity. Adaptive value of these effects depends on appropriate anticipation of environmental conditions in the next generation, and mismatch between conditions may contribute to disease. However, regulation of intergenerational plasticity is poorly understood. Dietary restriction (DR delays aging but maternal effects have not been investigated. We demonstrate maternal effects of DR in the roundworm C. elegans. Worms cultured in DR produce fewer but larger progeny. Nutrient availability is assessed in late larvae and young adults, rather than affecting a set point in young larvae, and maternal age independently affects progeny size. Reduced signaling through the insulin-like receptor daf-2/InsR in the maternal soma causes constitutively large progeny, and its effector daf-16/FoxO is required for this effect. nhr-49/Hnf4, pha-4/FoxA, and skn-1/Nrf also regulate progeny-size plasticity. Genetic analysis suggests that insulin-like signaling controls progeny size in part through regulation of nhr-49/Hnf4, and that pha-4/FoxA and skn-1/Nrf function in parallel to insulin-like signaling and nhr-49/Hnf4. Furthermore, progeny of DR worms are buffered from adverse consequences of early-larval starvation, growing faster and producing more offspring than progeny of worms fed ad libitum. These results suggest a fitness advantage when mothers and their progeny experience nutrient stress, compared to an environmental mismatch where only progeny are stressed. This work reveals maternal provisioning as an organismal response to DR, demonstrates potentially adaptive intergenerational phenotypic plasticity, and identifies conserved pathways mediating these effects.

  16. A nationwide radon concentration survey project in Japan. Outdoor and workplaces

    International Nuclear Information System (INIS)

    Oikawa, S.; Kanno, N.; Ohashi, N.; Abukawa, J.

    2003-01-01

    Nationwide survey for outdoor and workplace radon ( 222 Rn) concentration in Japan were carried out to evaluate the effective dose to the general public due to 222 Rn and its progeny. The 222 Rn concentration was measured by using passive-type radon/thoron discriminative monitor equipped with polycarbonate films. Concentration of 222 Rn was calculated from etch pit counts appeared on the polycarbonate film after chemical and electrochemical etching. For outdoor 222 Rn survey, the monitors were installed at about 700 points throughout Japan on every quarters of the fiscal year 1997 to 1999. The mean concentration of outdoor 222 Rn concentration was 6.1 Bq m -3 from the results of 696 measurement points. Seasonal variation of outdoor 222 Rn was found to be minimal in July to September, and maximal in October to December. For workplace 222 Rn survey, the monitors were installed at about 700 points in four categories (office, factory, school and hospital) on every quarters of the fiscal year 2000 to 2002. Nationwide mean 222 Rn concentration in workplaces was found to be 22.7 Bq m -3 for 2000 and 20.7 Bq m -3 for 2001, respectively. Seasonal variation of 222 Rn concentration measured at office, factory, school and hospital were also found to be minimal in July to September, and maximal in October to December. (author)

  17. Deposition of radon progeny in nonhuman primate nasal airways

    International Nuclear Information System (INIS)

    Yeh, H.C.; Cheng, Y.S.; Morgan, K.T.

    1992-01-01

    Radon progeny are usually associated with ultrafine particles ranging in diameter from 0.001 to 0.005 μm for open-quotes unattachedclose quotes progeny and from 0.005 to 0.2 μm for those attached to indoor aerosols. To assess the health effects of inhaling indoor radon progeny, it is necessary to study the regional deposition of these inhaled ultrafine particles. Laboratory animals are often used in studies of the toxicity of inhaled particles and vapors. Information on the deposition of particles larger than 0.2 μm in the nasal passages of laboratory animals is available; however, there is little information on the deposition of particles smaller than 0.2 μm. In this report, we describe the use of nasal casts of a rhesus monkey to measure total deposition of ultrafine aerosols, including unattached 220 Rn progeny, in a unidirectional-flow inhalation exposure system. Deposition data were obtained for monodisperse silver aerosols with particle sizes ranging from 0.005 to 0.2 μm, at several inspiratory and expiratory flow rates that represented normal breathing as well as hypo- and hyperventiliation. In addition, we studied the deposition of unattached 22- Rn progeny, at particle sizes from 0.001 to 0.003 μm. The deposition efficiency decreased with increasing particle size, indicating that diffusion was the dominant deposition mechanism. The effect of flow rate was essentially negligible. Based on assumptions that turbulent flow and complete mixing of aerosols occur in the nasal airways, a general equation E = 1-exp (-a D b Q c ) for d p ≤ 0.2 μm, was derived, where E is the deposition efficiency, d p is the particle diameter, D is the diffusion coefficient, and Q is the flow rate. Constants a, b, and c are estimated from experimental data, for either inspiration or expiration. This mathematical expression will be useful for making modifications to both deposition and dosimetry models

  18. Development of electret technology to measure indoor radon-daughter concentrations: Final report (Phase 1)

    International Nuclear Information System (INIS)

    Kotrappa, P.; Dempsey, J.C.; Stieff, L.R.

    1989-05-01

    A new type of radon progeny monitor called an electret radon progeny integrating sampling unit (E-RPISU) was developed and demonstrated which uses an electret ion chamber to measure the progeny concentration. A conventional 1 LPM particulate air sampling system is used to collect the progeny on a 35 cm 2 filter which is mounted on the side of the electret ion chamber such that the collected progeny are exposed to the inside of the chamber. The alpha radiation emitted by the progeny collected on the filter ionizes the air in the 220 ml chamber. The ions of opposite polarity collect on the surface of the 127 μm thick electret and reduce its surface voltage. A specially built surface voltmeter is used to measure the electret voltage before and after sampling. The electret voltage drop which occurs during the sampling period is shown to be proportional to the time integrated progeny concentration. Two prototype systems were fabricated and tested in homes and in calibrated radon chambers. The resulting data are presented and analyzed. The calibration factor for the E-RPISU ranged from 1.5 to 2.0 V/mWL-day depending on the electret voltage. Two of the E-RPISUs were delivered to UNC Geotech for further testing. 32 refs., 11 figs., 5 tabs

  19. Genetic diversity analysis of brassica napus/brassica campestris progenies using microsatellite markers

    International Nuclear Information System (INIS)

    Fayyaz, L.; Farhatullah, A.; Iqbal, S.; Kanwal, M.; Nawaz, I.

    2014-01-01

    Genetic diversity and relationship of F2 segregating progenies of interspecific crosses between B. napus N-501/B. campestris C-118 were studied. A set of 90 genotypes (2 parental lines and their 88 F2 progenies) was characterized separately using 24 microsatellite or SSR markers to cover the diversity as broadly as possibly present in them. In initial screening only 12 out of 24 SSR primers combination amplified DNA fragments, while the remaining 12 SSR primers did not amplify DNA fragment therefore those 12 SSR molecular markers were not used for further analysis. The 12 SSR primer combinations generated a total of 33 alleles, of that 32 were polymorphic loci, whereas only one was monomorphic locus. Primers BRMS-19 and BRMS-40 were highly polymorphic producing 4 bands each. Primer Ra2-D04 was less polymorphic and it produced only one band. The proportion of polymorphic loci was 95.83% which indicates high genetic diversity among the progenies. The average number of polymorphic alleles per locus was 2.66. The PIC values ranged from 0.395 for primer Ra2-E03 to 0.726 for primer BRMS-019 with an average genetic diversity (PIC value) of 0.584 per locus. Seven primers showed PIC values above 0.5 (50%) indicating high genetic diversity in the studied plant materials. Pair-wise similarity indices among 90 genotypes ranged from 0.3 to 0.95. Dendrogram obtained through UPGMA clustering of F2 progenies depicted eight main groups using similarity coefficient of 0.70. The progenies could be similar to their parents if they have the same banding patterns as that of the parents and could be distinguished from each other by the combination of fragments which are repeatedly present in one progeny and absent in the other. Considerable genetic diversity has been found among the F2 segregating progenies and their parents using SSR markers thus, SSR analysis proved to be a useful tool. (author)

  20. Genetic and epigenetic variations induced by wheat-rye 2R and 5R monosomic addition lines.

    Science.gov (United States)

    Fu, Shulan; Sun, Chuanfei; Yang, Manyu; Fei, Yunyan; Tan, Feiqun; Yan, Benju; Ren, Zhenglong; Tang, Zongxiang

    2013-01-01

    Monosomic alien addition lines (MAALs) can easily induce structural variation of chromosomes and have been used in crop breeding; however, it is unclear whether MAALs will induce drastic genetic and epigenetic alterations. In the present study, wheat-rye 2R and 5R MAALs together with their selfed progeny and parental common wheat were investigated through amplified fragment length polymorphism (AFLP) and methylation-sensitive amplification polymorphism (MSAP) analyses. The MAALs in different generations displayed different genetic variations. Some progeny that only contained 42 wheat chromosomes showed great genetic/epigenetic alterations. Cryptic rye chromatin has introgressed into the wheat genome. However, one of the progeny that contained cryptic rye chromatin did not display outstanding genetic/epigenetic variation. 78 and 49 sequences were cloned from changed AFLP and MSAP bands, respectively. Blastn search indicated that almost half of them showed no significant similarity to known sequences. Retrotransposons were mainly involved in genetic and epigenetic variations. Genetic variations basically affected Gypsy-like retrotransposons, whereas epigenetic alterations affected Copia-like and Gypsy-like retrotransposons equally. Genetic and epigenetic variations seldom affected low-copy coding DNA sequences. The results in the present study provided direct evidence to illustrate that monosomic wheat-rye addition lines could induce different and drastic genetic/epigenetic variations and these variations might not be caused by introgression of rye chromatins into wheat. Therefore, MAALs may be directly used as an effective means to broaden the genetic diversity of common wheat.

  1. Measurement of the deposited activity of the short-lived radon progeny in the human respiratory tract

    International Nuclear Information System (INIS)

    Vezzu, G.; Butterweck-Dempewolf, G.; Schuler, C.

    1998-01-01

    Volunteers were exposed in the radon chamber at Paul Scherrer Institut to an atmosphere enriched with highly unattached radon progeny. The deposited radon progeny activity in the respiratory tract of the volunteers was determined using a low level in-vivo counter. The detector arrangement and its calibration for the measurement of deposited radon progeny activity is described and the results for a mouth and a nose breathing volunteer are presented. For the nose breathing volunteer 55% of the deposited radon progeny activity was located in the head and the remaining 45% in the chest whereas for the mouth breathing volunteer 25% was located in the head and the remaining 75% in the chest. A mean clearance half-life for the deposited radon progeny from the respiratory tract of (2±1) h was obtained from the analyses of the temporal behaviour of the deposited radon progeny activity in the head. (orig.)

  2. Traceable measurements of the activity concentration in air

    CERN Document Server

    Paul, A; Forkel-Wirth, Doris; Müller, A; Marcos, A

    2002-01-01

    The nuclear reactions induced by high energetic protons in heavy targets such as UC/sub 2/ and ThC cause a particular, complex radiation protection task at facilities like ISOLDE: the measurement of a mixture of different isotopes of the radioactive noble gas radon and the radon progenies in air. The knowledge of their respective activity concentration is fundamental for exposure assessments. Due to the complex mixture of activity concentrations in air, its precise determination is quite difficult. Therefore, a new procedure for taking reference samples was developed and implemented for the traceable measurement of the activity concentration of radioactive ions (e.g., radon progenies) in air. This technique is combined by measuring alpha -particles with a multi-wire ionization chamber for the parallel on-line determination of the activity concentration of different radon isotopes. (10 refs).

  3. Selection of inbred maize (Zea mays L.) progenies by topcrosses conducted in contrasting environments.

    Science.gov (United States)

    Rodrigues, C S; Pacheco, C A P; Guedes, M L; Pinho, R G V; Castro, C R

    2016-09-23

    The aim of this study was to identify inbred progenies of S 0:1 maize (Zea mays L.) plants that were efficient at a low level of technology and responsive at a high level of technology through the use of topcrosses. Two contrasting environments were created using two levels of base fertilization and topdressing, so that the levels of nitrogen, phosphorus, and potassium were applied four times higher in one environment than in the other. We used S 0:1 progenies derived from commercial hybrids in topcrosses with two testers (an elite line from the flint heterotic group and an elite line from the dent heterotic group). The progenies and three controls were evaluated in an augmented block design in Nossa Senhora das Dores, SE, Brazil in the 2010 crop season. The average grain yield in the high-technological level was 21.44% greater than that in the low-technological level. There were no changes in progeny behavior in the two technological levels for grain yield. The testers did not differ in the average grain yield of the progenies at the two technological levels. Therefore, it is possible to select progenies derived from commercial hybrids that have an efficient response to fertilization.

  4. Seasonal variation in concentration of radon and thoron at non-uranium mines in China

    International Nuclear Information System (INIS)

    Cui Hongxing; Wu Yunyun; Zhang Qingzhao; Shang Bing

    2009-01-01

    Objective: To study the seasonal variation in concentrations of radon and thoron in non-uranium mine. Methods: Eight kinds of mineral types from 9 non-uranium mines were selected, including copper, gold, aluminium, manganese, antimonium, tungsten, copper-nickel and coal mines in 6 provinces, such as Yunnan, Shandong, Xinjiang, Heilongjiang, Hunan and Guizhou. LD-P R-T discriminative detectors were used to measure radon and thoron concentrations in underground mines during four seasons in one year. Results: Radon concentrations in underground mines showed a significantly seasonal variation. Radon concentration ranged from 35.5 to 4841 Bq/m 3 in summer, and the average value in four mines exceeded 1000 Bq/m 3 of the control limit for workplace (GB 18871-2002) . In winter, radon concentration ranged from 5 to 1917 Bq/m 3 , only one of them exceeded the control limit. The ratio of radon from summer to winter ranged from 2 to 12. Ventilation was one of the main factors which influenced the seasonal variation of radon. While the thoron concentration in underground mines showed a tendency that it was higher in summer and lower in winter. It was difficult to attain representative values for thoron, due to the influence of location of detectors. The seasonal variation of thoron should be further studied. Conclusions: Seasonal variation for radon and thoron should be taken into account to estimate the effective dose to miners. The values of radon concentration during the short term should be corrected. (authors)

  5. Chromosomal Behavior during Meiosis in the Progeny of Triticum timopheevii × Hexaploid Wild Oat.

    Directory of Open Access Journals (Sweden)

    Hongzhou An

    Full Text Available The meiotic behavior of pollen mother cells (PMCs of the F2 and F3 progeny from Triticum timopheevii × hexaploid wild oat was investigated by cytological analysis and sequential C-banding-genomic in situ hybridization (GISH in the present study. A cytological analysis showed that the chromosome numbers of the F2 and F3 progeny ranged from 28 to 41. A large number of univalents, lagging chromosomes, chromosome bridges and micronuclei were found at the metaphase I, anaphase I, anaphase II and tetrad stages in the F2 and F3 progeny. The averages of univalents were 3.50 and 2.73 per cell, and those of lagging chromosomes were 3.37 and 1.87 in the F2 and F3 progeny, respectively. The PMC meiotic indices of the F2 and F3 progeny were 12.22 and 20.34, respectively, indicating considerable genetic instability. A sequential C-banding-GISH analysis revealed that some chromosomes and fragments from the hexaploid wild oat were detected at metaphase I and anaphase I in the progeny, showing that the progeny were of true intergeneric hybrid origin. The alien chromosomes 6A, 7A, 3C and 2D were lost during transmission from F2 to F3. In addition, partial T. timopheevii chromosomes appeared in the form of univalents or lagging chromosomes, which might result from large genome differences between the parents, and the wild oat chromosome introgression interfered with the wheat homologues' normally pairing.

  6. Radon concentration in outdoor occupational environments in Aomori Prefecture, Japan

    International Nuclear Information System (INIS)

    Iyogi, T.; Ueda, S.; Hisamatsu, S.; Sakurai, N.; Inaba, J.

    2004-01-01

    The 222 Rn concentration in outdoor workplaces were measured in Aomori Prefecture, Japan as a part of a program on measurement of natural radiation background dose to people in the prefecture where Japan's first nuclear fuel cycling facilities are now under construction. 222 Rn concentrations were measured in 116 outdoor workplaces by passive Rn detectors for 10 months, which represented agricultural, forestry, fishery and construction/transportation workplaces. The 222 Rn concentrations in outdoor workplaces were generally lower than those in indoor environments. The dose to workers was estimated by using the results of the passive detectors as well as diurnal variation of 222 Rn and equilibrium factor measured with active-type detectors. The average dose from 222 Rn and its progenies to people in Aomori Prefecture was estimated as 0.39 mSv x y -1 based on the obtained results and results in indoor environments. The contribution of 222 Rn in outdoor workplaces to the total dose was 3.3% because of low occupancy ratio. (author)

  7. Unattached fraction and the size distribution of the radon progeny in indoor air

    International Nuclear Information System (INIS)

    Yamasaki, K.; Shimo, M.

    1992-01-01

    The size-distribution of the aerosol-attached radon progeny and the unattached (cluster) fraction were measured by using a low pressure cascade impactor and a single wire screen in a building of the nuclear facility. The radon concentration at the condition of ventilation 'ON' was about 50 Bq m -3 , but it increased exponentially after ventilation 'OFF' and reached to the saturated concentration of about 600 Bq m -3 . At the condition of low aerosol concentration without additional aerosol, the activity median aerodynamic diameter, the geometric standard deviation and the unattached fraction were, respectively, 0.4 μm, 2.7-2.9 and 0.3-0.5. On the other hand, at the condition of high aerosol concentration with burning a mosquito coil, these were, 0.4 μm, 2.1 and 0.02-0.03. These yield 2.5 times higher radiation dose conversion factors at the low aerosol condition than the high aerosol condition. (author)

  8. High Correlated Paternity Leads to Negative Effects on Progeny Performance in Two Mediterranean Shrub Species.

    Directory of Open Access Journals (Sweden)

    Sofia Nora

    Full Text Available Anthropogenic habitat deterioration can promote changes in plant mating systems that subsequently may affect progeny performance, thereby conditioning plant recruitment for the next generation. However, very few studies yet tested mating system parameters other than outcrossing rates; and the direct effects of the genetic diversity of the pollen received by maternal plants (i.e. correlated paternity has often been overlooked. In this study, we investigated the relation between correlated paternity and progeny performance in two common Mediterranean shrubs, Myrtus communis and Pistacia lentiscus. To do so, we collected open-pollinated progeny from selected maternal plants, calculated mating system parameters using microsatellite genotyping and conducted sowing experiments under greenhouse and field conditions. Our results showed that some progeny fitness components were negatively affected by the high correlated paternity of maternal plants. In Myrtus communis, high correlated paternity had a negative effect on the proportion and timing of seedling emergence in the natural field conditions and in the greenhouse sowing experiment, respectively. In Pistacia lentiscus, seedling emergence time under field conditions was also negatively influenced by high correlated paternity and a progeny survival analysis in the field experiment showed greater mortality of seedlings from maternal plants with high correlated paternity. Overall, we found effects of correlated paternity on the progeny performance of Myrtus communis, a self-compatible species. Further, we also detected effects of correlated paternity on the progeny emergence time and survival in Pistacia lentiscus, an obligate outcrossed species. This study represents one of the few existing empirical examples which highlight the influence that correlated paternity may exert on progeny performance in multiple stages during early seedling growth.

  9. Parental partners effects on progenies characteristics on hybridization within the Larix genus

    Energy Technology Data Exchange (ETDEWEB)

    Sindelar, J.; Frydl, J. [Forestry and Game Management Research Inst., Jiloviste (Czech Republic)

    1995-12-31

    Larch progenies of maternal clone No. 52-4-11 (Larix decidua Mill.) combined with the series of paternal clones of the same species and further of the Larix leptolepis Gord. and L. gmelini (Rupr.) Ledeb. species were evaluated on three research plots with larch (Larix sp.). Growth in height and thickness as well as stem forming were monitored at the age of 11 and 22 years. There was found out a significant share of variance falling on the action of mother, hence the existence of extra-nuclear heredity can be anticipated, particularly in interspecific hybrids. Comparing with the control in interspecific hybrids mostly luxuriant growth is displayed. On one of the studied plots there was found out the assumed growth depression in the quantitative characters of progenies originated from self-pollination. Some results of the research can be used as an auxiliary criterion in the selection of progenies and trees within the progenies for the establishment of seed orchards to produce hybrid seed of F2 generation. 24 refs, 6 figs, 6 tabs

  10. Parental partners effects on progenies characteristics on hybridization within the Larix genus

    Energy Technology Data Exchange (ETDEWEB)

    Sindelar, J; Frydl, J [Forestry and Game Management Research Inst., Jiloviste (Czech Republic)

    1996-12-31

    Larch progenies of maternal clone No. 52-4-11 (Larix decidua Mill.) combined with the series of paternal clones of the same species and further of the Larix leptolepis Gord. and L. gmelini (Rupr.) Ledeb. species were evaluated on three research plots with larch (Larix sp.). Growth in height and thickness as well as stem forming were monitored at the age of 11 and 22 years. There was found out a significant share of variance falling on the action of mother, hence the existence of extra-nuclear heredity can be anticipated, particularly in interspecific hybrids. Comparing with the control in interspecific hybrids mostly luxuriant growth is displayed. On one of the studied plots there was found out the assumed growth depression in the quantitative characters of progenies originated from self-pollination. Some results of the research can be used as an auxiliary criterion in the selection of progenies and trees within the progenies for the establishment of seed orchards to produce hybrid seed of F2 generation. 24 refs, 6 figs, 6 tabs

  11. Eggs and hatchlings variations in desert locusts: phase related characteristics and starvation tolerance

    Directory of Open Access Journals (Sweden)

    Koutaro Ould Maeno

    2013-12-01

    Full Text Available Locusts are grasshopper species that express phase polyphenism: modifying their behavior, morphology, coloration, life history and physiology in response to crowding. Desert locusts, Schistocerca gregaria, epigenetically modify progeny quality and quantity in response to crowding. Gregarious (crowded females produce larger but fewer progeny than do solitarious (isolated ones. The variability of progeny quality within single egg pod and the reasons why gregarious progeny have a better survival than solitarious ones remains unclear. This study investigated 1 the effects of rearing density on the variation in egg size within single egg pods 2 the starvation tolerance of hatchlings from mothers with different phases and 3 the physiological differences in hatchling energy reserve. Isolated females produced smaller but more eggs than did crowded ones. The variation in egg size within egg pods was greater in the latter than in the former. A negative relationship between egg size and number of eggs per egg pod was observed for both groups. Under starvation conditions, gregarious hatchlings survived significantly longer than solitarious ones. Among the solitarious hatchlings, the survival time was longer as hatchling body size increased. However, small individuals survived as long as large ones among the gregarious hatchlings. The percentage of water content per fresh body weight was almost equal between the two phases, before and after starvation. In contrast, the percentage of lipid content per dry body weight was significantly higher in gregarious hatchlings than in solitarious ones before starvation, but became almost equal after starvation. These results demonstrated that female locusts not only trade-off to modify their progeny size and number, but also vary progenies’ energy reserves. We hypothesized that gregarious females enhance their fitness by producing progeny differently adapted to high environmental variability and particularly to

  12. Inversion of the Jacobi-Porstendorfer room model for the radon progeny

    International Nuclear Information System (INIS)

    Thomas, J.; Jilek, K.; Brabec, M.

    2010-01-01

    The Jacobi-Porstendoerfer (J-P) room model describes the behaviour of radon progeny in the atmosphere of a room. It distinguishes between free and attached radon progeny in air. It has been successfully used without substantial changes for nearly 40 years. There have been several attempts to invert the model approximately to determine the parameters describing the physical processes. Here, an exact solution is aimed at as an algebraic inversion of the system of six linear equations for the five unknown physical parameters k, X, R, q f , q a of the room model. Two strong linear dependencies in this system, unfortunately do not allow to obtain a general solution (especially not for the ventilation coefficient k), but only a parameterized one or for reduced sets of unknown parameters. More, the impossibility to eliminate one of the two linear dependencies and the departures of the measured concentrations forces to solve a set of allowed combinations of equations of the algebraic system and to accept its mean values (therefore with variances) as a result of the algebraic inversion. These results are in agreement with results of the least squares method as well as of a sophisticated modern statistical approach. The algebraic approach provides, of course, a lot of analytical relations to study the mutual dependencies between the model parameters and the measurable quantities. (authors)

  13. Measurement of indoor radon-thoron and their progeny levels in dwellings and radon concentrations in ground water of Hassan city, Karnataka, India

    International Nuclear Information System (INIS)

    Srinivasa, E.; Rangaswamy, D.R.; Sannappa, J.

    2014-01-01

    The indoor radon and thoron concentrations in dwellings of Hassan city have been measured by using LR-115 type-Il Solid State Nuclear Tracks Detectors (SSNTDs). Measurements were carried in summer season from March to May-2013. The radon and thoron activity concentration in the corresponding dwellings has been found to vary from 7.4 to 45.7 Bqm -3 and 5.4 to 34.9 Bqm -3 with a median of 23.59±11 Bqm -3 and 14.47±8 Bqm -3 respectively. The overall average radon concentrations are found to be less than the lower reference level of 200 Bq m -3 of the International Commission on Radiological Protection. The annual effective dose received due to radon and its progeny by the inhabitants in the dwellings under study has also been calculated which found to vary from 0.320 ±0.4 to 1.86 ±1.1 mSv y -1 with an average value of 0.957±0.8 mSv -1 . The obtained results are much lower than the upper reference level of 10 mSv y -1 (ICRP 2007). Radon in bore well water at different locations of Hassan city was determined using the emanometry technique and exposure dose from ingestion of drinking water was estimated. The radon concentration in ground water was found to vary from 19.49 to 60.74 Bq l -1 with an average value of 47.16±14Bq l -1 . From this study it is evident that, the recorded ground water radon concentration values are higher than MCL of 11 Bq l -1 proposed by USEPA. The total dose due to inhalation and ingestion of 222 Rn in ground water ranges from 0.053 mSv y -1 to 0.165mSv y -1 with an average value of 0.127±0.038mSv y -1 . (author)

  14. Selection of arabica coffee progenies tolerant to heat stress

    Directory of Open Access Journals (Sweden)

    Alexsandro Lara Teixeira

    2015-07-01

    Full Text Available Due to high temperatures, practically all coffee farms in the state of Rondonia are of the C. canephora species. Thus, importing arabica coffee from other states becomes necessary for composition of blends, as well as for the specialty or gourmet coffee market. The purpose of this study was to select arabica coffee genotypes that exhibit satisfactory agronomic performance under high temperature conditions. The experiment was conducted in OuroPreto do Oeste, RO, Brazil, with mean annual temperature of 25.8°C and mean annual rainfall of 2300mm year-1. The experiment was composed of 114 arabica coffee genotypes, with 103 progenies and eleven control cultivars, provided by EPAMIG. A randomized block experimental design was used with three replications, spacing of 3.0x1.0 meters and five plants per plot. All the crop seasons showed significant difference for the green coffee yield trait. In joint analysis, significant differences were detected among progenies and control cultivars. In the average of the four harvests, green coffee yield was 32.38 bags ha-1. The cultivars 'CatuaíVermelho IAC 15', 'Obatã IAC 1669-20' and 'Catucaí Amarelo 2SLCAK' stood out, achieving yields greater than 40 bags ha-1. The gain obtained from selection was 14.33 bags ha-1, which is equivalent to an increase of 44.04% in production of green coffee. The progeny H514-7-10-6-2-3-9 stood out with an average yield of 51.20 bags ha-1. In regard to maturation cycle, 56% of the progenies were classified as early maturity and 44% as medium maturity. Late maturity genotypes were not observed

  15. Detection of somaclonal variation in micropropagated Hibiscus ...

    African Journals Online (AJOL)

    The main objective of micropropagation is to produce clones i.e. plants which are phenotypically and genetically identical to the mother plants. The culture of organized meristems usually guarantees the production of true-to-type plants but variations in the progenies have been widely reported. Hibiscus sabdariffa L. plants ...

  16. Radon: Chemical and physical states of radon progeny. Final technical report

    International Nuclear Information System (INIS)

    Castleman, A.W. Jr.

    1996-01-01

    The evolving chemical and physical form of radon progeny influence their transport to the bioreceptor and the extent to which that receptor can take up these species into various tissues. When first born following radioactive decay processes, the potentially deleterious radon progeny undergo various physical and chemical transformations as they transcend from a highly charged to a neutral state, and interact with various constituents of the environment. These transformations impact on the extent to which the radon progeny become associated with aerosol particles on the one hand, and their ultimate chemical form that is available for uptake in the biosystem, on the other. The program, which originally commenced in 1987, dealt with the basic chemistry and physics of radon progeny and hence impacted on several themes of importance to the DOE/OHER radon program. One of these is dose response, which is governed by the physical forms of the radon progeny, their transport to the bioreceptor and the chemical forms that govern their uptake. The second theme had to do with cellular responses, one of the major issues motivating the work. It is well known that various sizes of ions and molecules are selectively transported across cell membrane to differing degrees. This ultimately has to do with their chemical and physical forms, charge and size. The overall objective of the work was threefold: (1) quantifying the mechanisms and rates of the chemical and physical transformation; (2) ascertaining the ultimate chemical forms, and (3) determining the potential interactions of these chemical species with biological functional groups to ascertain their ultimate transport and incorporation within cells

  17. Genetic and epigenetic variations induced by wheat-rye 2R and 5R monosomic addition lines.

    Directory of Open Access Journals (Sweden)

    Shulan Fu

    Full Text Available BACKGROUND: Monosomic alien addition lines (MAALs can easily induce structural variation of chromosomes and have been used in crop breeding; however, it is unclear whether MAALs will induce drastic genetic and epigenetic alterations. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, wheat-rye 2R and 5R MAALs together with their selfed progeny and parental common wheat were investigated through amplified fragment length polymorphism (AFLP and methylation-sensitive amplification polymorphism (MSAP analyses. The MAALs in different generations displayed different genetic variations. Some progeny that only contained 42 wheat chromosomes showed great genetic/epigenetic alterations. Cryptic rye chromatin has introgressed into the wheat genome. However, one of the progeny that contained cryptic rye chromatin did not display outstanding genetic/epigenetic variation. 78 and 49 sequences were cloned from changed AFLP and MSAP bands, respectively. Blastn search indicated that almost half of them showed no significant similarity to known sequences. Retrotransposons were mainly involved in genetic and epigenetic variations. Genetic variations basically affected Gypsy-like retrotransposons, whereas epigenetic alterations affected Copia-like and Gypsy-like retrotransposons equally. Genetic and epigenetic variations seldom affected low-copy coding DNA sequences. CONCLUSIONS/SIGNIFICANCE: The results in the present study provided direct evidence to illustrate that monosomic wheat-rye addition lines could induce different and drastic genetic/epigenetic variations and these variations might not be caused by introgression of rye chromatins into wheat. Therefore, MAALs may be directly used as an effective means to broaden the genetic diversity of common wheat.

  18. Radon progeny dose conversion coefficients for Chinese males and females

    Energy Technology Data Exchange (ETDEWEB)

    Yu, K.N. E-mail: peter.yu@city.edu.hk; Cheung, T.T.K.; Haque, A.K.M.M.; Nikezic, D.; Lau, B.M.F.; Vucic, D

    2001-07-01

    The airway dimensions for Caucasian males have been scaled by multiplying by factors 0.95 and 0.88 to give those for Chinese males and females, respectively. Employing the most recent data on physical and biological parameters, the radiation doses to the basal and secretory cells due to {alpha} particles from {sup 218}Po and {sup 214}Po, homogeneously distributed in the mucous layer, have been calculated. The emission of {alpha} particles has been simulated by a Monte Carlo method. For both basal and secretory cells, the dose conversion coefficients (DCCs) for physical conditions of sleep, rest, light and heavy exercise, have been obtained for Chinese males and females for unattached progeny, and for attached progeny of diameters 0.02, 0.15, 0.25, 0.30 and 0.50 {mu}m. For basal cells, the coefficients lie in the range 0.69-6.82 mGy/(J s/m{sup 3}) or 8.7-86 mGy/WLM for unattached progeny and in the range 0.045-1.98 mGy/(J s/m{sup 3}) or 0.57-25 mGy/WLM for attached progeny. The corresponding ranges for Caucasian males are 1.27-8.81 mGy/(J s/m{sup 3}) or 16-111 mGy/WLM{sup -1} and 0.05-2.30 mGy/(J s/m{sup 3}) or 0.64-29 mGy/WLM. For secretory cells, the coefficients lie in the range 0.095-16.82 mGy/(J s/m{sup 3}) (1.2-212 mGy/WLM) for unattached progeny and in the range 0.095-6.67 mGy/(J s/m{sup 3}) (1.2-84 mGy/WLM) for attached progeny. The corresponding ranges for Caucasian males are 0.34-21.51 mGy/(J s/m{sup 3}) (4.3-271 mGy/WLM) and 0.1-7.78 mGy/(J s/m{sup 3}) (1.3-98 mGy/WLM). The overall DCCs calculated for a typical home environment are 0.59 and 0.52 mSv/(J s/m{sup 3}) (7.4 and 6.5 mSv/WLM) for Chinese males and females, respectively, which are 80 and 70% of the value, 0.73 mSv/(J s/m{sup 3}) (9.2 mSv/WLM), for Caucasian males.

  19. Chromosomal instability in the progeny of irradiated parents

    International Nuclear Information System (INIS)

    Voro btsova, I.E.; Vorobyova, M.V.; Bogomazova, A.N.

    1997-01-01

    Genomic instability have been demonstrated in irradiated cells as the increased frequency of sporadic chromosome aberrations persisted over multiple generations of cell divisions. We found that chromosomal instability characterized as well the somatic cells of irradiated parents progeny. It means that radiation induced genomic instability can be transmitted via germ line cells. As a measure of instability the sensitivity of chromosomes to radiation was estimated. In animal experiments the irradiation of mature germ cells of male rats (dose - 4.5 Gy of X-rays) increase the frequency of chromosome aberrations induced by challenging irradiation in regenerating hepatocytes, in bone marrow cells and in fetal fibroblasts in the progeny of irradiated male rats. The chromosomal sensitivity of cultivated lymphocytes to in vitro irradiation (1.5 Gy of γ(rays 137 Cs) is increased in the children born parents undergone antitumor radiotherapy or worked as 'liquidators' of Chernobyl accident consequences before conception in comparison to the children of unexposed parents. The cytogenetic radiosensitivity of lymphocytes to irradiation in vitro is also increased in children evacuated from contaminated by radionuclides areas ('positive' control group). The increased spontaneous frequency of chromatid-type acentric was found in all group of children with irradiation history. The instability of genome of irradiated parents progeny seems could be the mechanism of these health effects. (authors)

  20. Aubergine Controls Germline Stem Cell Self-Renewal and Progeny Differentiation via Distinct Mechanisms.

    Science.gov (United States)

    Ma, Xing; Zhu, Xiujuan; Han, Yingying; Story, Benjamin; Do, Trieu; Song, Xiaoqing; Wang, Su; Zhang, Ying; Blanchette, Marco; Gogol, Madelaine; Hall, Kate; Peak, Allison; Anoja, Perera; Xie, Ting

    2017-04-24

    Piwi family protein Aubergine (Aub) maintains genome integrity in late germ cells of the Drosophila ovary through Piwi-associated RNA-mediated repression of transposon activities. Although it is highly expressed in germline stem cells (GSCs) and early progeny, it remains unclear whether it plays any roles in early GSC lineage development. Here we report that Aub promotes GSC self-renewal and GSC progeny differentiation. RNA-iCLIP results show that Aub binds the mRNAs encoding self-renewal and differentiation factors in cultured GSCs. Aub controls GSC self-renewal by preventing DNA-damage-induced Chk2 activation and by translationally controlling the expression of self-renewal factors. It promotes GSC progeny differentiation by translationally controlling the expression of differentiation factors, including Bam. Therefore, this study reveals a function of Aub in GSCs and their progeny, which promotes translation of self-renewal and differentiation factors by directly binding to its target mRNAs and interacting with translational initiation factors. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Field applications of a radon barrier to reduce indoor airborne progeny

    International Nuclear Information System (INIS)

    Culot, M.V.J.; Olson, H.G.; Schiager, K.J.

    1978-01-01

    The use of uranium mill tailings in the foundations of dwellings has resulted in indoor radon progeny concentrations and gamma exposures in excess of levels presently allowed for the general public. An account is given of the applications of an epoxy coating on the indoor faces of the concrete foundations of three buildings in Grand Junction, Colorado. Epoxy barriers were shown to be effective for preventing radon influx into structures. Gamma exposure rates must be analyzed to ensure that buildup behind the barrier will not introduce an unacceptable gamma exposure level. The use of a sealant is especially economical in situations where structural integrity may be jeopardized by physical removal of uranium mill tailings. (author)

  2. Improvement in genetic characteristics and oil yield of selected soybean progenies from octuple crosses

    Directory of Open Access Journals (Sweden)

    Hamawaki Osvaldo Toshiyuki

    2000-01-01

    Full Text Available The objective of the present study was to evaluate 44 soybean octuple crosses in the F4:3[8] and F5:3[8] generations in order to select progenies superior for seed oil yield (OY and other important agronomic characteristics. Octuple crosses were hybridized in a chain mating system. In one group, crosses were carried out for three generations with the adapted x exotic parents until octuple crosses with 75% adapted genes and 25% exotic genes were obtained. In a second group, hybridization of adapted x adapted parents originated crosses with 100% adapted genes. During the growing season 1994/95, the progenies F4:3[8] were evaluated by using the augmented block design. The progenies F5:3[8] were evaluated during the growing season 1995/96 in three experiments using augmented block design without repetition. The octuple crosses gave origin to superior progenies for all the characters studied. In the C22 cross, OY values were 707 kg/ha. The estimates of heritability in relation to the crosses average resulted in the following mean, minimum and maximum values, respectively: number of days to maturity (52.35%, 3.71%, 84.23%; agronomic value (26.69%, 1.62%, 61.28% and grain yield (29.28%, 1.52%, 61.06%. The observed genetic gains for grain yield in the early, intermediate and late F5:3[8] progenies were superior to the expected genetic gains and the observed genetic gains for OY were more expressive in the early and late F5:[8] progenies. The genetic variability remaining in the selected progenies of some crosses suggests that further genetic gains for grain yield and OY might be possible with advanced selection cycles.

  3. Study of temporal variation of radon concentrations in public drinking water supplies

    International Nuclear Information System (INIS)

    York, E.L.

    1995-01-01

    The Environmental Protection Agency (EPA) has proposed a Maximum Contaminant Level (MCL) for radon-222 in public drinking water supplies of 300 pCi/L. Proposed monitoring requirements include collecting quarterly grab samples for the first year, then annual samples for the remainder of the compliance cycle provided first year quarterly samples average below the MCL. The focus of this research was to study the temporal variation of groundwater radon concentrations to investigate how reliably one can predict an annual average radon concentration based on the results of grab samples. Using a open-quotes slow-flowclose quotes collection method and liquid scintillation analysis, biweekly water samples were taken from ten public water supply wells in North Carolina (6 month - 11 month sampling periods). Based on study results, temporal variations exist in groundwater radon concentrations. Statistical analysis performed on the data indicates that grab samples taken from each of the ten wells during the study period would exhibit groundwater radon concentrations within 30% of their average radon concentration

  4. Radon and radon progeny in 70 houses in the Tennessee Valley area: study design and measurement methods

    International Nuclear Information System (INIS)

    Dudney, C.S.; Hawthorne, A.R.; Monar, K.P.; Quillen, J.L.; Clark, C. Jr.; Doane, R.W.; Wallace, R.G.; Reed, R.P.

    1986-01-01

    Levels of radon and its short-lived airborne progeny are being measured in a year-long study of 70 houses in four states in the Tennessee Valley. Various methods were used to solicit volunteers with differing degrees of success. Criteria for selection of houses in the study included presence of a lower level with cement floor and one or more block walls in contact with the soil, absence of obvious indications of technologically enhanced sources of radium, and proximity to one of four cities, (Knoxville, Chattanooga, Birmingham, or Florence). By design, most houses in the study are in the same neighborhood as at least one other house in the study. Houses range in age from newly constructed to about 40 years old. Most of the houses have more than 2000 square feet of finished floor space. The lower level encompasses a garage in most cases. More complete information pertaining to house characteristics will be gathered in the course of the study. Measurements are being made to obtain information on both location- and season-dependent variation of radon and radon progeny. Simultaneous measurements are made quarterly on both upper and lower levels of each house. Grab samples of air are collected and analyzed for radon using a modified Lucas cell technique. Short-term (10-minute) samples of airborne particulate material are collected and analyzed for radon progeny. One-week integrated measurements of working levels are made once each quarter using modified thermoluminescent dosimeters. Both three- and twelve-month integrated measurements of radon using track-etch monitors are being made. 19 references, 1 figures

  5. Unattached fraction of radon progeny in Polish coal mines

    International Nuclear Information System (INIS)

    Skubacz, K.; Michalik, B.

    2002-01-01

    The system of the monitoring of the radiation hazard in Polish coal mines is based on the monitoring of the workplaces. This system works since 1989 in all coal mines. It gives a very good basis for further epidemiological investigation and assessment of the health detriment within the population of the mines as a result of the exposure for natural radiation. It is very important problem, due to the fact of the presence in the mines another factors, which probably have a synergetic effects on the respiratory tracts. As the routine instrument, a device called ALFA-31 sampling probe was developed in our laboratory. This device was accomplished to regular dust sampler and simultaneous measurements of dust content and potential alpha energy concentration of radon progeny are obligatory in all underground mines in Poland. But the microcyclone used a separator of the respirable fraction which causes the cut-off of unattached fraction of radon progeny, On the other hand measurements of the unattached fraction of short lived radon progeny play a very important role in the investigations of the adequate dose from this source of radiation hazard. During field experiments the use of the alpha spectroscopy system is necessary, while measurements are done not in the vacuum chambers but under normal pressure. It leads to situation, when particular peaks in alpha spectrum are very wide and interfere with other peaks of another alpha-emitting radionuclides. Such instrumentation was designed and completed, and a survey in several underground mines was performed. The analysis of the obtained results must be done very carefully; in other case it may cause a very big uncertainty of the result. In this paper a new approach to the analysis of the alpha spectra has been described. This approach can be used also in other applications of alpha spectroscopy, in which the analysis of energy of alpha peaks in spectrum is needed. The method of the analysis is based on a non-linear regression

  6. Estimation of equilibrium factors of radon and its progeny using SSNTDs in the various dwellings of Hyderabad, Andhra Pradesh, India

    International Nuclear Information System (INIS)

    Yadagiri Reddy, P.; Rama Reddy, K.; Sreenath Reddy, M.

    2013-01-01

    In the estimation of effective dose in the indoor environment due to Radon and its progeny the equilibrium factor (F) plays a significant role. It is the radioactive equilibrium between radon and its short-lived decay products. Generally in the dose estimation is made taking the equilibrium factor 0.4 (UNSCEAR value) for the radon and its progeny. But in practice the concentration of radon and its progeny vary significantly with local environmental conditions and time, subsequently the equilibrium factor F also changes and hence affects the effective dose estimation of a particular dwelling. Therefore the UNSCEAR F value does not reflect the actual effective doses. Therefore, the present study is carried out to estimate the equilibrium factors in different types of dwellings in the urban Hyderabad using SSNTDs. It is found that, the equilibrium factors in the urban Hyderabad vary from 0.01 to 0.71 with an average 0.32 ± 0.23. The average F values of urban Hyderabad relatively lower than Indian average and global average. The reasons for the lower equilibrium factor values in the study area have been discussed in this paper. (author)

  7. Seasonal variation of radon concentration in different rooms of dwellings

    International Nuclear Information System (INIS)

    Jayasheelan, A.; Manjunatha, S.; Chandrashekaraiah, G.; Shankar, P.; Umeshareddy, K.; Ningappa, C.

    2016-01-01

    Indoor air is a dominant exposure for humans, where more than half of the body's intake during a lifetime. The main natural sources of indoor radon are soil, building materials like sand, rocks, cement, marble, bricks, ceramics, natural gas and the underground-derived water supply. In the present research, dwellings with similar building style (similar floorings and dimensions) from Tumkur city were studied for indoor radon, thoron and their progeny measurements for various seasons

  8. Intercomparison and intercalibration of passive/active radon and active radon progeny instruments and methods in North America

    International Nuclear Information System (INIS)

    George, A.C.; Tu, Keng W.

    1993-06-01

    An intercomparison and intercalibration exercise for radon and radon progeny measurements made with active and passive instruments was held at EML from October 22--30,1992. Twenty-five participants submitted 96 passive integrating devices, eight active devices for radon, and seven integrating devices for potential alpha energy concentration (PAEC). In addition, 40 grab samples for radon progeny analysis were taken by five groups that participated in person during the intercomparison. The results reported to EML indicate that the majority of the participants (70%) obtained mean results within 10% of the EML reference value. Although the instruments used in this exercise are based on different principles of collection and detection, they all appear reliable. However, in some instances there seemed to be some minor problems with quality control and calibration bias. Also, the large counting errors for the PAEC experienced by some of the participants can be minimized by using higher sampling air flow rates without sacrificing instrument portability

  9. Variations of surface ozone concentration across the Klang Valley, Malaysia

    Science.gov (United States)

    Latif, Mohd Talib; Huey, Lim Shun; Juneng, Liew

    2012-12-01

    Hourly air quality data covering the period 2004-2008 was obtained from the Air Quality Division, the Department of Environment (DOE) through long-term monitoring by Alam Sekitar Sdn. Bhd. (ASMA) were analysed to investigate the variations of surface ozone (O3) in the Klang Valley, Malaysia. A total of nine monitoring stations were selected for analysis in this study and the results show that there are distinct seasonal patterns in the surface O3 across the Klang Valley. A high surface O3 concentration is usually observed between January and April, while a low surface O3 concentration is found between June and August. Analysis of daily variations in surface O3 and the precursors - NO, NO2, CO, NMHC and UVb, indicate that the surface O3 photochemistry in this study area exhibits a positive response to the intensity and wavelength in UVb while being influenced by the concentration of NOx, particularly through tritration processes. Although results from our study suggested that NMHCs may influence the maximum O3 concentration, further investigation is required. Wind direction during different monsoons was found to influence the concentration of O3 around the Klang Valley. HYSPLIT back trajectories (-72 h) were used to indicate the air-mass transport patterns on days with high concentrations of surface O3 in the study area. Results show that 47% of the high O3 days was associated with the localized circulation. The remaining 32% and 22% were associated with mid-range and long-range transport across the South China Sea from the northeast.

  10. Risk assessment of exposure to radon concentration in indoor atmosphere and drinking water of Shimoga city, Karnataka, India

    International Nuclear Information System (INIS)

    Rangaswamy, D.R.; Sannappa, J.; Srinivasa, E.

    2016-01-01

    The exposure of population to natural sources of radiation has become an important issue in terms of radiological protection. The major contribution of dose from natural radiation in normal background regions arises due to inhalation of alpha-emitting radon and thoron, and their progenies, which are ubiquitous in both indoor and outdoor environs. The aim of the present study is to measure indoor radon, thoron and their progeny levels in the dwellings of Shimoga city and radon concentration in drinking water and to estimate the annual effective dose. The indoor concentration of radon, thoron and their progeny was measured using Solid-State Nuclear Track Detectors (SSNTDs) based twin chamber dosimeter cups. The 222 Rn concentration in drinking water was estimated by the Emanometry technique

  11. Patterns of Diel Variation in Nitrate Concentrations in the Potomac River

    Science.gov (United States)

    Burns, D. A.; Miller, M. P.; Pellerin, B. A.; Capel, P. D.

    2015-12-01

    The Potomac River is the second largest source of nitrogen to Chesapeake Bay, where reducing nutrient loads has been a focus of efforts to improve estuarine trophic status. Two years of high frequency sensor measurements of nitrate (NO3-) concentrations in the Upper Potomac River at the Little Falls gage were analyzed to quantify seasonal variation in the magnitude and timing of the apparent loss of NO3- from the water column that results from diel-driven processes. In addition to broad seasonal and flow-driven variation in NO3- concentrations, clear diel patterns were evident in the river, especially during low flow conditions that follow stormflow by several days. Diel variation was about 0.01 mg N/L in winter and 0.02 to 0.03 mg N/L in summer with intermediate values during spring and fall. This variation was equivalent to 10% occurred during some summer days. Maximum diel concentrations occurred during mid- to late-morning in most seasons, with the most repeatable patterns in summer and wider variation in timing during fall and winter. Diel NO3- loss diminished loads by about 0.6% in winter and 1.3% in summer, and diel-driven processes were minor compared to estimates of total in-stream NO3- loss that averaged about one-third of the inferred groundwater NO3- contribution to the river network. The magnitude of diel NO3- variation was more strongly related to metrics based on water temperature and discharge than to metrics based on photosynthetically active radiation. Despite the fairly low diminishment of NO3- loads attributable to diel variation, estimates of diel NO3- uptake were fairly high compared to published values from smaller streams and rivers. The diel NO3- patterns observed in the Potomac River are consistent with photosynthesis of periphyton as a principal driver which may be linked to denitrification through the release of labile carbon. The extent to which these diel patterns are related to measures of aquatic metabolism are unknown as is the role

  12. Unattached fraction and the aerosol size distribution of the radon progeny in a natural cave and mine atmospheres

    International Nuclear Information System (INIS)

    Butterweck, G.; Porstendoerfer, J.; Reineking, A.; Kesten, J.

    1992-01-01

    Measurements of the activity size distribution of aerosol-attached radon progeny and the amount of unattached radon daughters have been performed in mine atmospheres and a tourist cave. During working hours a large number (10 5 -10 6 cm -3 ) of aerosol particles is generated in mines, mainly by diesel engines. The activity size distribution of these aerosol particles has smaller median diameters (AMAD about 200 nm) than the aged aerosol existing in the mine during non-working hours (AMAD about 350 nm). Strictly correlated to the aerosol concentration, the unattached fraction of the radon progeny, f p , in the tourist cave (3000 particles per cm 3 ) is higher (f p = 0.1) than in mines (f p 0.01) during working hours. This yields 1.4-2.5 times higher radiation dose conversion factors in the natural cave than in mines under working conditions. (author)

  13. Temporal variation of carbonyl compound concentrations at a semi-rural site in Denmark

    DEFF Research Database (Denmark)

    Christensen, C.S.; Skov, H.; Nielsen, T.

    2000-01-01

    The atmospheric concentrations of formaldehyde, acetaldehyde and acetone were measured by the DNPH-technique at the semi-rural site Lille Valby, Denmark (55 degrees N) between May-July 1995, The average concentrations were observed to be 1.2 ppbv for formaldehyde, 0.8 ppbv for acetaldehyde and 1.......9 ppbv for acetone, For the set of carbonyl compounds, concentrations were found to be highly correlated, though only during daytime, The weak correlations observed during nighttime are believed to be caused by the dry deposition of especially formaldehyde, During periods with low photochemical activity...... of hydrocarbons during long-range transport. Especially, the concentration levels of acetone showed a pronounced seasonal-variation with the highest levels observed during summertime and lowest in winter and spring. The seasonal variation in the concentration levels of formaldehyde and acetaldehyde were small...

  14. Daily variation of the radon concentration indoors and outdoors and the influence of meteorological parameters

    International Nuclear Information System (INIS)

    Porstendoerfer, J.; Butterweck, G.; Reineking, A.

    1994-01-01

    Series of continuous radon measurements in the open atmosphere and in a dwelling, including the parallel measurement of meteorological parameters, were performed over a period of several weeks. The radon concentration in indoor and outdoor air depends on meteorological conditions. In the open atmosphere the radon concentration varies between 1 and 100 Bq m -3 , depending on weather conditions and time of day. During time periods of low turbulent air exchange (high pressure weather with clear night sky), especially in the night and early morning hours (night inversion layer), the diurnal variation of the radon concentration showed a pronounced maximum. Cloudy and windy weather conditions yield a small diurnal variation of the radon concentration. Indoors, the average level and the diurnal variation of the indoor radon concentration is also influenced by meteorological conditions. The measurements are consistent with a dependence of indoor radon concentrations on indoor-outdoor pressure differences. 11 refs., 4 figs

  15. Indoor radon progeny aerosol size measurements in urban, suburban, and rural regions

    International Nuclear Information System (INIS)

    Tu, K.W.; Knutson, E.O.; George, A.C.

    1991-01-01

    By using direct and indirect methods, the authors conducted size distribution measurements of radon progeny particles in a variety of indoor environments in urban, suburban, and rural areas. The radon progeny particle size distribution owing to indoor activities has two definable source categories: (1) gas combustion from stoves and kerosene heaters - particles were found to be smaller than 0.1 μm in diameter, mostly in the range 0.02-0.08 μm; and (2) cigarette smoking and food frying - particles were found to be larger, in the size range 0.1-0.2 μm. The radon progeny particle size distribution, without significant indoor activities, such as cooking, was found to be larger in rural areas than in urban or suburban areas. The modal diameters of the size spectra in the rural areas were two to three times larger than those in urban or suburban areas, around 0.3-0.4 bs. 0.1-0.2 μm. Results obtained by applying the attachment theory to the measured number-weighted size spectra from an electrical aerosol size analyzer support this finding. These results, if confirmed by more extensive studies, will be useful for the assessment of the risk from the inhalation of radon progeny in various indoor environments

  16. New strategy for evaluating grain cooking quality of progenies in dry bean breeding programs

    Directory of Open Access Journals (Sweden)

    Bruna Line Carvalho

    2017-04-01

    Full Text Available The methodology available for evaluating the cooking quality of dry beans is impractical for assessing a large number of progenies. The aims of this study were to propose a new strategy for evaluating cooking quality of grains and to estimate genetic and phenotypic parameters using a selection index. A total of 256 progenies of the 13thcycle of a recurrent selection program were evaluated at three locations for yield, grain type, and cooked grains. Samples of grains from each progeny were placing in a cooker and the percentage of cooked grains was assessed. The new strategy for evaluating cooking quality was efficient because it allowed a nine-fold increase in the number of progenies evaluated per unit time in comparison to available methods. The absence of association between grain yield and percentage of cooked grains or grain type indicated that it is possible to select high yielding lines with excellent grain aspect and good cooking properties using a selection index.

  17. Inherited effects in F1 progeny of partially sterile male phthorimaea operculella (Lepidoptera: Gelechiidae)

    International Nuclear Information System (INIS)

    Makee, H.; Saour, G.

    1998-01-01

    Adult male phthorimaea operculella (Zeller), were exposed to sub sterilizing doses of gamma irradiation: 100, 150 and 200 Gy. Inherited effects in the F 1 , progeny of irradiated male parents were examined. Mean developmental time and the percentage mortality of the F 1 progeny, of each examined dose, were higher than that of the control group. Moreover, the sex ratio of the F 1 , progeny was skewed in favor of the males. Mean longevity, fecundity, and the percentage fertility of the F 1 progeny were lower than those of their parents and the control group. Mating ability and the frequency of mating of F 1 adults were similar to those of their partially sterile male parents and the control. The genetic basis of the F 1 characteristics has been discussed. The use of sub sterilizing doses of irradiation could be considered as an important component in a potato tuber moth control strategy. (author). 17 refs., 3 tabs

  18. Need for an integrated approach towards the assessment of radon, thoron and their progeny exposures

    International Nuclear Information System (INIS)

    Mayya, Y.S.

    2008-01-01

    Recent publications dealing with epidemiological studies on North American and European populations have indicated statistically significant lung cancer risk coefficients attributable to residential radon exposures. These are essentially based on radon gas itself as the quantitative measure of exposures. However, considering that true exposures depend upon the intricate mechanisms of decay product deposition in the lung, it is necessary to go for the assessment of decay products including their size distributions and deposition velocities. This approach is essential for assessing the risks of thoron and its decay products which is of considerable importance in the public domain and in the thorium fuel cycle. The recent development of deposition based progeny concentration measurement techniques appear to be best suited for radiological risk assessments both among occupational workers and general study populations. These provide an easy to wear alternative for radon inhalation dosimetry similar to TLDs for external gamma radiations. It is urgently required to characterize their performance under a variety of residential indoor and workplace conditions. This may be achieved through an integrated multi-parametric study programme involving measurements of radon, thoron and their progeny concentrations along with fine and coarse fractions and indoor source terms. This will not only in delineate the true exposure profiles and indoor parameters (e.g. deposition velocities and air exchange rates) in the country, but also will help in establishing deposition dosimetry as a basic technique for inhalation exposure estimations for occupational workers and subjects living in high background radiation areas

  19. Cellular dosimetry for radon progeny alpha particles in bronchial tissue

    International Nuclear Information System (INIS)

    Mohamed, A.; Hofmann, W.; Balashazy, I.

    1996-01-01

    Inhaled radon progeny are deposited in different regions of the human bronchial tree as functions of particle size and flow rate. Following deposition and mucociliary clearance, the sensitive bronchial basal and secretory cells are irradiated by two different alpha particle sources: (i) radon progeny in the sol and/or gel phase of the mucous layer, and (ii) radon progeny within the bronchial epithelium. In the case of internally deposited radionuclides, direct measurement of the energy absorbed from the ionizing radiation emitted by the decaying radionuclides is rarely, if ever, possible. Therefore, one must rely on dosimetric models to obtain estimates of the spatial and temporal patterns of energy deposition in tissues and organs of the body. When the radionuclide is uniformly distributed throughout the volume of a tissue of homogeneous composition and when the size of the tissue is large compared to the range of the particulate emissions of the radionuclide, then the dose rate within the tissue is also uniform and the calculation of absorbed dose can proceed without complication. However, if non-uniformities in the spatial and temporal distributions of the radionuclide are coupled with heterogeneous tissue composition, then the calculation of absorbed dose becomes complex and uncertain. Such is the case with the dosimetry of inhaled radon and radon progeny in the respiratory tract. There are increasing demands to obtain a definitive explanation of the role of alpha particles emitted from radon daughters in the induction of lung cancer. Various authors have attempted to evaluate the dose to the bronchial region of the respiratory tract due to the inhalation of radon daughters

  20. Immunological status of the progeny of breeder hens kept on ochratoxin A (OTA)-contaminated feed.

    Science.gov (United States)

    Zahoor-Ul-Hassan; Khan, Muhammad Zargham; Khan, Ahrar; Javed, Ijaz; Saleemi, Muhammad Kashif

    2011-06-01

    This study aimed to evaluate the immunological status of the progeny of breeder hens kept on ochratoxin A (OTA)-contaminated feed. For this purpose, 84 White Leghorn (WL) layer breeder hens (40-weeks-of-age) were divided into seven groups (A-G). Hens in the Group A were fed a commercial layer ration while those in Groups B-G were kept on a diet amended with 0.1, 0.5, 1.0, 3.0, 5.0, or 10.0 mg OTA/kg, respectively, for 3 weeks. Fertile eggs were set for hatching on the weekly basis to get the progeny of each week separately. Hatched chicks (n = 10 from each group) were euthanized at Day 14 of age, and their immunological organs weighed and fixed in neutral buffered formalin. An indirect immunoperoxidase method was applied to study the frequency of immunoglobulin(s)-bearing cells in the spleen and bursa of Fabricius from these progeny. From other chicks within each set, at Day 16 of age, lymphoblastogenic responses against an intradermal administration of phytohemagglutinin (PHA-P) were determined. Relative weights of the bursa of Fabricius and of the thymus were significantly lower in the progeny of hens fed OTA-contaminated diet for 14 and 21 days. The frequencies of IgA-, IgG-, and IgM-bearing cells were also significantly (P ≤ 0.05) lower in the bursa of Fabricius and spleen of the progeny chicks obtained from dams fed the OTA-mixed diet. Progeny chicks obtained from the breeder hens fed higher doses of OTA showed significantly lower responses to PHA-P than did counterpart chicks from control hens. The findings of this study suggested that there were immunosuppressive effects from OTA in the progeny obtained from breeder hens kept on OTA-contaminated diets.

  1. Epistasis between QTLs for bone density variation in Copenhagen × dark agouti F2 rats

    OpenAIRE

    Koller, Daniel L.; Liu, Lixiang; Alam, Imranul; Sun, Qiwei; Econs, Michael J.; Foroud, Tatiana; Turner, Charles H.

    2009-01-01

    The variation in several of the risk factors for osteoporotic fracture, including bone mineral density (BMD), has been shown to be strongly influenced by genetic differences. However, the genetic architecture of BMD is complex in both humans and in model organisms. We previously reported quantitative trait locus (QTL) results for BMD from a genome screen of 828 F2 progeny of Copenhagen and dark agouti rats. These progeny also provide an excellent opportunity to search for epistatic effects, o...

  2. Asociación del color de la concha de reproductores de Argopecten purpuratus (Lamarck, 1819 con la supervivencia, crecimiento y desarrollo larval de sus progenies Association between shell color of breeds (Lamarck, 1819 and the survival, growth and larval development of their progenies

    Directory of Open Access Journals (Sweden)

    Ricardo M García

    2012-07-01

    most frequent shell colors. Knowing that Argopecten purpuratus shell color variation is under genetic control, in this work we test the hypothesis that loci that control shell color variation also affect larvae's growth rate, survival and/or development rate. Survival, growth and development rates were estimated in larvae produced in different crosses between brooders of A. purpuratus having low frequency shell colors (white or orange and "normal" (brown color. Results showed no significant differences in growth rates between larvae produced by crosses that involved brown shell parents, or orange by white parents. However, progenies of self fertilized orange and white parents showed significant differences in growth among them, and a lower growth rate than the remaining crosses. Results suggest that genes that control shell color variation in juvenile and adult A. purpuratus could affect the growth rates of their larvae, but not the development rate or survival.

  3. Variation in caffeine concentration in single coffee beans.

    Science.gov (United States)

    Fox, Glen P; Wu, Alex; Yiran, Liang; Force, Lesleigh

    2013-11-13

    Twenty-eight coffee samples from around the world were tested for caffeine levels to develop near-infrared reflectance spectroscopy (NIRS) calibrations for whole and ground coffee. Twenty-five individual beans from five of those coffees were used to develop a NIRS calibration for caffeine concentration in single beans. An international standard high-performance liquid chromatography method was used to analyze for caffeine content. Coffee is a legal stimulant and possesses a number of heath properties. However, there is variation in the level of caffeine in brewed coffee and other caffeinated beverages. Being able to sort beans on the basis of caffeine concentration will improve quality control in the level of caffeine in those beverages. The range in caffeine concentration was from 0.01 mg/g (decaffeinated coffee) to 19.9 mg/g (Italian coffee). The majority of coffees were around 10.0-12.0 mg/g. The NIRS results showed r(2) values for bulk unground and ground coffees were >0.90 with standard errors coffee beans. One application of this calibration could be sorting beans on caffeine concentration to provide greater quality control for high-end markets. Furthermore, bean sorting may open new markets for novel coffee products.

  4. Effect of strenuous maternal exercise before and during pregnancy on rat progeny renal function

    Directory of Open Access Journals (Sweden)

    Oliveira A.O.

    2004-01-01

    Full Text Available The effects of strenuous exercise before and during pregnancy on the renal function and morphological alterations of the progeny were determined in a study on female Wistar rats. This research was done based on a previous study carried out in our laboratory, which showed morphological alterations in rats submitted to this kind of exercise. As the form is related to the function, the physiological relevance of submitting a pregnant female to a high-intensity exercise training regimen could be explained by the fact that morphological alterations can influence kidney function. The animals were assigned to one of two groups: control animals that did not exercise during pregnancy and trained animals that swam for 120 min 5 days a week for 8 weeks before pregnancy and daily for 60 min over a period of 8 weeks starting on the second day of pregnancy. Seven rats of each group were analyzed for morphological alterations and for renal function. The progeny of the rats used for morphological evaluation were born by cesarean section and the progeny of the animals used to evaluate renal function were born normally. The progeny were two months old when renal function was evaluated. Fertility and morbidity were the same for both groups. Strenuous maternal exercise had no significant influence on glomerular filtration rate (GFR but renal plasma flow was lower in the progeny of the trained group (mean ± SD, 16.65 ± 3.77 ml min-1 kg-1 compared to the progeny of the control group (33.42 ± 2.56 ml min-1 kg-1. Antidiuretic and antinatriuretic effects on the progeny of the trained group were observed, since urine flow as percentage of GFR and the fraction of urinary sodium excretion were lower in this group (1.38 ± 0.10 and 0.60 ± 0.04%, respectively compared to the progeny of the control group (2.36 ± 0.11 and 1.55 ± 0.20%, respectively. Moreover, in this exercise program, fetuses from trained animals were small-sized (2.45 ± 0.19 vs 4.66 ± 2.45 g for

  5. A passive method for the determination of the equilibrium factor between radon gas and its short period progeny

    International Nuclear Information System (INIS)

    Lopez, Fabio O.; Canoba, Analia C.

    2001-01-01

    Due to the radiological importance of 222 Rn gas and its progeny of short period it is extremely necessary to count with an adequate methodology for the determination of its concentration in the different atmospheres in which human activity is developed. In this work a method was developed to determine the concentration of 222 Rn gas and the equilibrium factor between the concentration of the gas and its descendants, by means of a single device that has two Makrofol passive tracks detector. This device is completely passive and integrating, conditions that make it very appropriate to be used in any atmospheres in which human activity is developed, for example in houses, schools, places of work, underground mines, etc. (author)

  6. Age and sex dependent inhalation doses to members of the public from indoor thoron progeny

    Energy Technology Data Exchange (ETDEWEB)

    Bi, L; Tschiersch, J [Helmholtz Zentrum Muenchen-German Research Center for Environmental Health, Institute of Radiation Protection, D-85764, Neuherberg (Germany); Li, W B [Helmholtz Zentrum Muenchen-German Research Center for Environmental Health, Department of Medical Radiation Physics and Diagnostics, D-85764, Neuherberg (Germany); Li, J L, E-mail: bilei1983@gmail.com [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China)

    2010-12-01

    The increased indoor thoron level in Europe, North America and Asia has shown that the exposure to thoron and its decay products cannot be ignored in some environments. The contribution of thoron and its progeny can be a significant component of the total exposure from radon and thoron. In the present paper, radiation dose assessment of members of the public of different age and sex exposed to {sup 220}Rn progeny under different daily life activities is performed through a dosimetric approach. Dose conversion coefficients under typical indoor conditions were estimated to be in the range of 107 nSv (Bq h m{sup -3}){sup -1} for infant to 81.7 nSv (Bq h m{sup -3}){sup -1} for adult. The results of this work emphasized that small children receive a radiation dose of 25% more than adults under the same conditions, and people performing exercise receive a radiation dose 100% more than when sleeping. The results of this work are appropriate to the risk assessment of thoron exposure to members of the public who live in areas with high radon and thoron concentrations.

  7. Evaluasi Resistensi Progeni Anggrek Phalaenopsis terhadap Penyakit Busuk Lunak (Pseudomonas viridiflava

    Directory of Open Access Journals (Sweden)

    Hanudin Hanudin

    2018-01-01

    Full Text Available A bacterial soft rot disease caused by P. viridiflava was one of problems in orchid nursery, especially Phalaenopsis.  An evaluation on progenies derived from three crossing combinations were conducted to find out the symptom characteristic, development of infections of the disease and resistance response of the progenies against artificial infection of P. viridiflava. The research was conducted under a standard glass house conditions for Phalaenopsis involving 31 individuals from 3 progeny populations, namely P.157, E.2153 and E.2189. The results showed that symptoms were characterized by the lesion of the leaf tissues. On most accessions, the lesion enlarged and foul odor was detected as an indication of the successful establishment of bacterial infection. Based on the disease severity, three accessions (P.157-12, P.157-45, and P.157-71 had the lowest infections and were classified into resistant genotypes. One accession, i.e. P.157-32 was classified as susceptible and the rest 27 accessions were grouped into very susceptible class.

  8. Progeny of male rats treated with methadone: physiological and behavioural effects.

    Science.gov (United States)

    Joffe, J M; Peruzović, M; Milković, K

    1990-04-01

    Male rats were injected with methadone HCl (METH) at 5 mg/kg s.c. for 4 days prior to mating with drug-free females. Offspring resulting from these matings were compared with offspring of drug-free males. The progeny of METH-treated males gained less weight after weaning and had lighter thymuses as adults (but not in infancy). Gonadal weights did not differ in infancy or adulthood, and adrenal weights were heavier in female offspring in adulthood. In adulthood METH offspring were significantly different from controls on all behavioural tests used (open field activity, activity cage activity, passive avoidance latencies, shuttle box avoidances, and rotarod latencies), with the differences frequently affected by test order, days of testing, or sex of offspring. The effects in progeny of METH-treated males in the absence of differences in litter size or neonatal mortality indicate that paternal drug ingestion prior to mating can produce physiological and behavioural changes in progeny that are not dependent on detectable effects on early viability or growth.

  9. Effect of pollination mode on progeny of Panicum coloratum var. makarikariense: Implications for conservation and breeding

    Directory of Open Access Journals (Sweden)

    Lorena V. Armando

    2017-09-01

    Full Text Available Panicum coloratum var. makarikariense, a perennial grass native to Africa, is adapted to a wide range of soil and climatic conditions with potential to be used as forage in tropical and semi-arid regions around the world. Our objective was to understand how the pollination mode affects viable seed production and further survival of the progeny. We evaluated self- and open-pollinated progenies from different accessions by measuring the seed production of the parents and their germination performance, germination rate and seedling survival. Parents and progeny were also fingerprinted with Simple Sequence Repeats (SSR. Progeny produced through open-pollination resulted in significantly more filled seeds and superior seedling survival than self-pollination. These results indicate that accessions studied here rely heavily on cross-pollination, whereas the contribution of self-pollinated offspring to the population is likely to be low. SSR profiles showed that, on average, 85% of the progeny (arising from cross-pollination possessed paternal specific markers and 100% of them were genetically different from the maternal genotype. All plants examined had 4x = 36 chromosomes. Overall, our findings indicate that var. makarikariense is able to generate highly polymorphic progeny through segregation and recombination. This study provides reference information for the formulation of appropriate strategies for pasture germplasm management, conservation and development of breeding programs. 

  10. Studies on thoron progeny implantation in different materials

    International Nuclear Information System (INIS)

    Cosma, C.; Flore, A.; Pop, I.

    2003-01-01

    The purpose of this work is to obtain the alpha spectra for thoron daughters implanted at the surface of different materials and to show the possibility of this method to simulate the radon progeny implantation and thus to find some parameters used in the Jacobi model

  11. Measurements and statistical analyses of indoor radon concentrations in Tokyo and surrounding areas

    International Nuclear Information System (INIS)

    Sugiura, Shiroharu; Suzuki, Takashi; Inokoshi, Yukio

    1995-01-01

    Since the UNSCEAR report published in 1982, radiation exposure to the respiratory tract due to radon and its progeny has been regarded as the single largest contributor to the natural radiation exposure of the general public. In Japan, the measurement of radon gas concentrations in many types of buildings have been surveyed by national and private institutes. We also carried out the measurement of radon gas concentrations in different types of residential buildings in Tokyo and its adjoining prefectures from October 1988 to September 1991, to evaluate the potential radiation risk of the people living there. One or two simplified passive radon monitors were set up in each of the 34 residential buildings located in the above-mentioned area for an exposure period of 3 months each. Comparing the average concentrations in the buildings of different materials and structures, those in the concrete steel buildings were always higher than those in the wooden and the prefabricated mortared buildings. The radon concentrations were proved to become higher in autumn and winter, and lower in spring and summer. Radon concentrations in an underground room of a concrete steel building showed the highest value throughout our investigation, and statistically significant seasonal variation was detected by the X-11 method developed by the U.S. Bureau of Census. The values measured in a room at the first floor of the same concrete steel building also showed seasonal variation, but the phase of variation was different. Another multivariate analysis suggested that the building material and structure are the most important factors concerning the levels of radon concentration among other factors such as the age of the building and the use of ventilators. (author)

  12. Assessment of radiological effect of the indoor radon and its progeny

    International Nuclear Information System (INIS)

    Ramachandran, T.V.; Subbaramu, M.C.; Mishra, U.C.

    1988-01-01

    Of all the sources of environmental radiation, radon and its progeny are considered to be responsible for a significant dose to man, especially when they are in enclosed areas like underground mines, caves, cellars, poorly designed and badly ventilated houses. Linear extrapolation from the dose response value of the uranium miners exposed to higher levels of radon and its daughters also suggest that the majority of the lung cancer incidence could be due to radon. Higher indoor radon levels and shift in the disequilibrium of the progeny concentration in dwellings caused by the lower ventilation rate leads to severalfold increase of lung cancer incidence from radon. The large risk which is anticipated calls for further studies in this field and may also lead to the conclusion that the slight, but much feared, burden due to man-made radioactivity could be more than compensated by controlling critical segments of the environmental radioactivity. In this report the study of risk due to breathing of indoor radon is briefly reviewed. Dose equivalent to the exposed tissue of the respiratory tract of the people living in dwellings are evaluated. Like most of the risk assessment of low level radiation, the effort to quantify the effect of radon in terms of death rate dose due to lung cancer attributable to radon levels indoors, has to rely on the extrapolation from the effects of the higher exposure rate. In situations where soil or building materials contain elevated radium levels, living in energy efficient houses may be as dangerous as heavy smoking. (author). 8 tabs., 5 figs., 41 refs

  13. Microclimatic effects on outdoor radon and its progeny in a long-term study

    International Nuclear Information System (INIS)

    Schuetz, M.; Keller, G.; Kappel, R.J.A.

    1994-01-01

    The dose due to the long term radon exposure is estimated from the radon concentration and from an equilibrium factor that in the literature is reported with a wide uncertainty. Therefore the radon equilibrium factor outdoors and its dependence on climatic effects should be investigated in a long-term study. Both the outdoor concentrations of radon and of its progeny near Ellweiler/Hunsrueck were measured continuously during 12 months and the resulting equilibrium factors were determined. Simultaneously to the every 2 hour's radon data many meterological parameters as temperature and relative to humidity of the air, barometric pressure and duration and amount of rainfall were recorded. At a height of 6 meters above ground and in 10 minute intervals the local wind direction and velocity were registered. By that a set of more than 3000 single measurements of the equilibrium factor and of the corresponding weather conditions was collected

  14. Comparison of methods and instruments for 222Rn/220Rn progeny measurement

    International Nuclear Information System (INIS)

    Liu Yanyang; Shang Bing; Wu Yunyun; Zhou Qingzhi

    2012-01-01

    In this paper, comparisons were made among three methods of measurement (grab measurement, continuous measurement and integrating measurement) and also measurement of different instruments for a radon/thoron mixed chamber. Taking the optimized five-segment method as a comparison criterion, for the equilibrium-equivalent concentration of 222 Rn, measured results of Balm and 24 h integrating detectors are 31% and 29% higher than the criterion, the results of Wl x, however, is 20% lower; and for 220 Rn progeny, the results of Fiji-142, Kf-602D, BWLM and 24 h integrating detector are 86%, 18%, 28% and 36% higher than the criterion respectively, except that of WLx, which is 5% lower. For the differences shown, further research is needed. (authors)

  15. Detection of atmospheric tritium by scintillation. Variations in its concentration in France; Detection du tritium atmospherique par scintillation. Evolution de sa concentration en France

    Energy Technology Data Exchange (ETDEWEB)

    Bibron, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-06-01

    The tritium released into the atmosphere as a result of the explosion of thermonuclear devices is a useful radioactive tracer for the study of certain geophysical problems. The low concentrations found however call for the use of extremely sensitive detectors. Two detection methods using liquid scintillators are described. In the first method, the sample is introduced into the scintillator in liquid form, after prior concentration of the tritium by electrolysis. In the second method the tritium is incorporated into the scintillator solvent molecule by chemical synthesis. In the last part of the report are examined the variations in the tritium concentration in rain-water and of the free hydrogen in the air in France. A discussion is then made of the seasonal variations in the case of rain-water and these are compared to the variations in the strontium-90 concentrations. (author) [French] Le tritium introduit dans l'atmosphere par les explosions d'armes thermonucleaires est un traceur radioactif Interessant pour l'etude de certains problemes de geophysique. Les faibles concentrations rencontrees obligent toutefois a utiliser des detecteurs extremement sensibles. On decrit deux methodes de detection utilisant des scintillateurs liquides. Dans la premiere methode, l'echantillon est introduit dans le scintillateur, sous forme aqueuse, apres une concentration prealable du tritium par electrolyse. Dans la seconde methode, le tritium est incorpore a la molecule du solvant du scintillateur par synthese chimique. Dans la derniere partie du rapport, on examine l'evolution de la concentration du tritium dans les eaux de precipitation et l'hydrogene libre de l'air en France. On discute ensuite les variations saisonnieres dans le cas des eaux de precipitation et on les compare aux variations du strontium 90. (auteur)

  16. Detection of atmospheric tritium by scintillation. Variations in its concentration in France; Detection du tritium atmospherique par scintillation. Evolution de sa concentration en France

    Energy Technology Data Exchange (ETDEWEB)

    Bibron, R. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-06-01

    The tritium released into the atmosphere as a result of the explosion of thermonuclear devices is a useful radioactive tracer for the study of certain geophysical problems. The low concentrations found however call for the use of extremely sensitive detectors. Two detection methods using liquid scintillators are described. In the first method, the sample is introduced into the scintillator in liquid form, after prior concentration of the tritium by electrolysis. In the second method the tritium is incorporated into the scintillator solvent molecule by chemical synthesis. In the last part of the report are examined the variations in the tritium concentration in rain-water and of the free hydrogen in the air in France. A discussion is then made of the seasonal variations in the case of rain-water and these are compared to the variations in the strontium-90 concentrations. (author) [French] Le tritium introduit dans l'atmosphere par les explosions d'armes thermonucleaires est un traceur radioactif Interessant pour l'etude de certains problemes de geophysique. Les faibles concentrations rencontrees obligent toutefois a utiliser des detecteurs extremement sensibles. On decrit deux methodes de detection utilisant des scintillateurs liquides. Dans la premiere methode, l'echantillon est introduit dans le scintillateur, sous forme aqueuse, apres une concentration prealable du tritium par electrolyse. Dans la seconde methode, le tritium est incorpore a la molecule du solvant du scintillateur par synthese chimique. Dans la derniere partie du rapport, on examine l'evolution de la concentration du tritium dans les eaux de precipitation et l'hydrogene libre de l'air en France. On discute ensuite les variations saisonnieres dans le cas des eaux de precipitation et on les compare aux variations du strontium 90. (auteur)

  17. Measurement of unattached radon progeny based in electrostatic deposition method

    International Nuclear Information System (INIS)

    Canoba, A.C.; Lopez, F.O.

    1999-01-01

    A method for the measurement of unattached radon progeny based on its electrostatic deposition onto wire screens, using only one pump, has been implemented and calibrated. The importance of being able of making use of this method is related with the special radiological significance that has the unattached fraction of the short-lived radon progeny. Because of this, the assessment of exposure could be directly related to dose with far greater accuracy than before. The advantages of this method are its simplicity, even with the tools needed for the sample collection, as well as the measurement instruments used. Also, the suitability of this method is enhanced by the fact that it can effectively be used with a simple measuring procedure such as the Kusnetz method. (author)

  18. Seasonal variations in heavy metal concentrations in soil and some ...

    African Journals Online (AJOL)

    In this study, the seasonal variations in concentrations of the heavy metals - As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn - in soil and crops from a farm near the refuse dump site of Obafemi Awolowo University, Ile-Ife, Nigeria were investigated during the two major seasons of Nigeria. This was done to assess the pollution ...

  19. Local deposition patterns of inhaled radon progeny in human bronchial airways

    International Nuclear Information System (INIS)

    Heistracher, T.; Hofmann, W.; Balashazy, I.

    1996-01-01

    The local distribution of radon decay products deposited within bronchial bifurcations, particularly the formation of hot spots, may be more relevant for the determination of cellular doses in bronchial tissue than the commonly computed deposition efficiency, which is conceptually equivalent to the assumption of a uniform nuclide distribution. It is well known that the initial states of lung cancer in humans preferably occur in upper airways close to the cardinal location. In this study we use a recently developed geometric approach of a physiologically realistic bifurcation to demonstrate the site sensitivity of radon progeny deposition for two particle sizes, which are representative of the unattached and attached fraction of radon progeny

  20. Indoor thoron and radon progeny measurements

    International Nuclear Information System (INIS)

    Tu, K.W.; George, A.C.; Lowder, W.M.; Gogolak, C.V.

    1992-01-01

    Measurements of indoor thoron ( 220 Rn) and radon ( 222 Rn) progeny activities were conducted in 40 homes and six public buildings in five states. A commercial alpha spectrometer system and four portable alpha integrating sampling monitors using diffused junction silicon detectors were used for sampling and recording of radionuclide data in particular the potential alpha energy concentrations (PAEC). The data were analysed for the ratios of PAEC- 220 Rn to PAEC- 222 Rn, and the correlations between the two quantities, and their estimated annual effective dose equivalent (AEDE). The results show that the PAEC ratios were 0.09, 0.6, 0.55, and 0.47, respectively, for all homes with the PAEC- 222 Rn > 400, between 100 and 400, -3 , and the total of all homes tested; the AEDE ratios were 0.03, 0.21, 0.19 and 0.16, respectively. No strong correlations were found between PAEC- 220 Rn and PAEC- 222 Rn, and between basement and ground floor data for PAEC- 220 Rn, but the PAEC- 222 Rn data showed a strong correlation between the basement and the ground floor values. Simultaneous measurements of PAEC- 220 Rn and PAEC- 222 Rn on the ground floor and in the basement of each of the 23 single-family houses tested suggests that 220 Rn entry from building materials may be as significant as from the underlying soil. (author)

  1. Lipid peroxidation and seed emergency in progenies of the yellow passion fruit plant

    Directory of Open Access Journals (Sweden)

    João Paulo Bestete de Oliveira

    2012-09-01

    Full Text Available The objective was to evaluate the percentage of emergency plantlets and lipid peroxidation in seeds of 29 half-sib progenies of yellow passion fruit (Passiflora edulis Sims. after 24 months under storage. The experimental design was completely randomized, with four replications of 50 seeds each, from which the treatments were the progenies (1-29. The evaluation of the percent plantlet emergency was accomplished at 14 and 28 days after sowing. The lipid peroxidation of the seeds was expressed as malondialdehyde (MDA content that was determined by the TBARS method. Approximately 21% of those half-sib progenies maintained the viability of their seeds for twenty-four months under storage. The results point out a remarkable genetic variability for vigor and emergency of the yellow passion fruit plantlets, with occurrence of individuals with high and other ones with low capacity to maintaining the physiologic quality of their seeds after storage.

  2. Wire screens as a tool for survey measurements of the unattached radon progeny in mines

    International Nuclear Information System (INIS)

    Janica, R.

    1996-07-01

    The radon hazard in mines is assessed by measuring the radioactivity accumulated on filters through which air is forced to flow. The filter collects both forms of the short-lived radon progeny, attached and unattached, and, therefore, the assessment is based on the measurement of the total radon progeny. Because of the special radiological significance of the unattached fraction of the short-lived radon progeny, the estimation of the radiation hazard to miners would be improved if the unattached fraction could be measured. This report describes two methods of measurement for the simultaneous determination of the unattached and the total radon progeny. The proposed methods comply with the criterion of practicality (imposed by the working conditions in the mine environment), that is, they are implemented using standard survey equipment and simple procedures. Both methods use wire screens to collect, preferentially, the unattached fraction. According to the first method, air is sampled through a wire screen and a backup filter, and the radioactivity accumulated on both the filter and the wire screen are measured separately using standard counting protocols (e.g. the Kusnetz protocol). The wire screen's efficiency for collecting the unattached radon progeny is determined, in advance, under laboratory conditions. The method assumes the validity of the collection efficiencies when the screens are used under field conditions. To avoid the uncertainty of the lab-determined collection efficiency, a new measuring method was proposed based on the sampling of air through two screens in series and a backup filter. The measurement of the ratio of the activities deposited on both screens allows an estimation of the screen collection efficiency under field conditions. Once this is done, the 'unattached fraction' and total radon progeny are determined by counting only one of the screens and the backup filter as described in the previous method. (author). 73 refs., 8 tabs., 21 figs

  3. Growth and Crown Vigor of 25 Year-Old Shortleaf Pine Progenies on a Littleleaf Disease Site

    Science.gov (United States)

    Stanley J. Zarnoch; John L. Ruehle; Roger P. Belanger; Donald H. Marx; W. Craig Bryan

    1994-01-01

    On a littleleaf disease site in South Carolina, most of the control-pollinated progeny of shrotleaf pines that appeared to be reesistant to the disease outperformed a check seedlot through age 25. Rankings of progeny based on volume changed little between ages 17 and 25.

  4. Relationship of 220Rn and 222Rn progeny levels in Canadian underground U mines

    International Nuclear Information System (INIS)

    Bigu, J.

    1988-01-01

    Radon-222 and 220 Rn progeny are found in some Canadian underground U mines. Because both can contribute to lung dose, their experimental determinations are important. The relationship between 222 Rn progeny Working Level [WL(Rn)] and 220 Rn progeny Working Level [WL(Tn)] has been investigated in U mines. Experimental measurements extended from 1981 to 1986 and consisted of about 700 measurements of each WL(Rn) and WL(Tn). The data were analyzed by standard linear and power-function regression analysis. A power-function relationship between WL(Rn) and WL(Tn) seemed to fit the experimental data best. The relationship obtained permits the calculation of WL(Tn) from experimental values of WL(Rn). The relationship is useful for lung-dose-calculation purposes and in mine-ventilation-engineering calculations

  5. Paternal cocaine taking elicits epigenetic remodeling and memory deficits in male progeny.

    Science.gov (United States)

    Wimmer, M E; Briand, L A; Fant, B; Guercio, L A; Arreola, A C; Schmidt, H D; Sidoli, S; Han, Y; Garcia, B A; Pierce, R C

    2017-11-01

    Paternal environmental perturbations including exposure to drugs of abuse can produce profound effects on the physiology and behavior of offspring via epigenetic modifications. Here we show that adult drug-naive male offspring of cocaine-exposed sires have memory formation deficits and associated reductions in NMDA receptor-mediated hippocampal synaptic plasticity. Reduced levels of the endogenous NMDA receptor co-agonist d-serine were accompanied by increased expression of the d-serine degrading enzyme d-amino acid oxidase (Dao1) in the hippocampus of cocaine-sired male progeny. Increased Dao1 transcription was associated with enrichment of permissive epigenetic marks on histone proteins in the hippocampus of male cocaine-sired progeny, some of which were enhanced near the Dao1 locus. Finally, hippocampal administration of d-serine reversed both the memory formation and synaptic plasticity deficits. Collectively, these results demonstrate that paternal cocaine exposure produces epigenetic remodeling in the hippocampus leading to NMDA receptor-dependent memory formation and synaptic plasticity impairments only in male progeny, which has significant implications for the male descendants of chronic cocaine users.

  6. Seasonal and diurnal variation in concentrations of gaseous and particulate phase endosulfan

    Science.gov (United States)

    Li, Qingbo; Wang, Xianyu; Song, Jing; Sui, Hongqi; Huang, Lei; Li, Lu

    2012-12-01

    Successive 52-week air monitoring of α-endosulfan (α-E), β-endosulfan (β-E) and endosulfan sulfate (E.S) in the gaseous and particulate phases was conducted in Dalian city, northeast China by using an active high-volume sampler. Significant seasonal and diurnal variations in endosulfan concentrations were observed. It was found that the concentration of gaseous-phase α-E peaked in the summer and the concentration of particulate phase α-E peaked in the winter. For E.S, both gaseous and particulate phase concentrations peaked in the summer. α-E was distributed predominantly in the gas phase in the summer but was distributed mainly in the particulate phase in the winter. β-E was distributed mainly in the gas phase in the summer and in the particulate phase at other times of the year. E.S was distributed mainly in the particulate phase throughout the year. Elevated temperatures facilitated the volatilization of α-E from particle surfaces but exerted little effect on β-E and had almost no effect on E.S. Trajectory-based analysis indicates that the seasonal variation in atmospheric concentrations of endosulfan in Dalian city was influenced strongly by the land and sea air masses. In addition, differences in endosulfan concentrations in the particulate phase between day and night were likely due to the circulation of sea/land breezes. The 'cold-condensation' effect occurring during the night may result in the attachment of endosulfan to the particulate phase.

  7. A family business: stem cell progeny join the niche to regulate homeostasis.

    Science.gov (United States)

    Hsu, Ya-Chieh; Fuchs, Elaine

    2012-01-23

    Stem cell niches, the discrete microenvironments in which the stem cells reside, play a dominant part in regulating stem cell activity and behaviours. Recent studies suggest that committed stem cell progeny become indispensable components of the niche in a wide range of stem cell systems. These unexpected niche inhabitants provide versatile feedback signals to their stem cell parents. Together with other heterologous cell types that constitute the niche, they contribute to the dynamics of the microenvironment. As progeny are often located in close proximity to stem cell niches, similar feedback regulations may be the underlying principles shared by different stem cell systems.

  8. Variability and performance evaluation of introgressed Nigerian dura x Deli dura oil palm progenies.

    Science.gov (United States)

    Noh, A; Rafii, M Y; Mohd Din, A; Kushairi, A; Norziha, A; Rajanaidu, N; Latif, M A; Malek, M A

    2014-04-03

    Twelve introgressed oil palm (Elaeis guineensis) progenies of Nigerian dura x Deli dura were evaluated for bunch yield, yield attributes, bunch quality components and vegetative characters at the Malaysian Palm Oil Board Research Station, in Keratong, Pahang, Malaysia. Analysis of variance revealed significant to highly significant genotypic differences, indicating sufficient genetic variability among the progenies for bunch yield and its attributes, vegetative characters and bunch quality components, except fruit to bunch ratio. Fresh fruit bunch yield ranged from 167 kg·palm(-1)·year(-1) in PK1330 to 212 kg·palm(-1)·year(-1) in PK1351, with a mean yield of 192 kg·palm(-1)·year(-1). Among the progeny, PK1313 had the highest oil to bunch ratio (19.36%), due to its high mesocarp to fruit ratio, fruit to bunch ratio and low shell to fruit ratio. Among the progenies, PK1313 produced the highest oil yield of 31.4 kg·palm(-1)·year(-1), due to a high mesocarp to fruit ratio (61.2%) and a low shell to fruit ratio (30.7%), coupled with high fruit to bunch ratio (65.6%). PK1330 was found promising for selection, as it had desirable vegetative characters, including smaller petiole cross section (27.15 cm2), short rachis length (4.83 m), short palm height (1.85 m), and the lowest leaf number (164.6), as these vegetative characters are prerequisites for selecting palms for high density planting and high yield per hectare. The genetic variability among the progenies was found to be high, indicating ample scope for further breeding, followed by selection.

  9. Optimization of filtration for control of exposure to radon progeny

    International Nuclear Information System (INIS)

    Curling, C.A.; Rudnick, S.N.; Ryan, P.B.; Moeller, D.W.

    1989-01-01

    The theoretical optimization of filter characteristics that minimize an individual's dose from the inhalation of radon progeny is described. The computer simulation presented combines models for a well-mixed room, lung deposition, and lung dose equivalent. A modified form of the Jacobi-Porstendorfer room model and the Jacobi-Eisfeld lung dosimetry model are used for the simulation. The parameters of the filter that are optimized include the filter's solidity, thickness, and fiber diameter. Room ventilation, particle size distribution and concentration, and other factors are specified. The theoretical model is used to determine optimal filter characteristics for reducing the lung dose equivalent under specified room conditions. The resulting optimal design is a thin filter (0.1 - 0.7 mm) of low solidity (0.5 - 1.0%) and relatively large diameter fibers (30 - 100 μm). This model indicates that a significant reduction in the dose-equivalent rate can be achieved through the use of a properly designed recirculating filter system

  10. Parentage assignment of progeny in mixed milt fertilization of ...

    African Journals Online (AJOL)

    Administrator

    2011-06-13

    Jun 13, 2011 ... individuals. Overall, 98.8% of progeny were assigned to their parents using Family Assignment. Program (FAP). Selection of hyper-variable microsatellites in Caspian brown trout to identify unique alleles was effective for unambiguous parentage determination and estimation of genetic diversity in this study.

  11. Effect of Polish and foreign purebred Arabian stallions on conformation traits of their progeny participating in shows in the last decade

    Directory of Open Access Journals (Sweden)

    Rafal Czarnecki

    2014-12-01

    Full Text Available Observations confirm correctness of the statement that the best recommendation for a stallion is his progeny. The aim of this study was indicating purebred Arabian stallions passing on to their progeny best conformation traits, assessed in Polish shows, in the past decade, taking into consideration their origin. The analysis included national and foreign stallions used in Polish breeding of purebred Arabian horses, which are fathers of at least 5 heads of progeny. The authors own research proved that progeny of foreign stallions statistically differed significantly from the progeny sired by Polish stallions within all conformation traits tested in shows. In the studied period, the highest final score (91.37 points and note for the trait type (19.11 points was characteristic of the progeny of QR Marc. The best head was passed on by stallions: QR Marc (19.06 points and WH Justice (18.78 points, born in the United States and owned by the European breeders. In the Top Ten of producers passing on a refined head to their progeny, there was only one Polish stallion bred in the Horse Stud Michalw, Ekstern (18.29 points. Progeny with the most correct body structure was sired by foreign stallions, Eden C (18.13 points and QR Marc (18.13 points, and by the Polish stallion, Zlocien (17.95 points. The highest score for the trait legs was obtained by the progeny of the Qatar stallion Gazal Al Shaqab (16.30 points. However, the title of the father of the best movers got an Israeli stallion, Laheeb (18.91 points.

  12. The effect of copper-amended fertiliser and copper oxide wire particles on the copper status of farmed red deer (Cervus elaphus) and their progeny.

    Science.gov (United States)

    Grace, N D; Wilson, P R; Quinn, A K

    2005-02-01

    To determine changes in serum and liver copper concentrations in postnatal, weaner, yearling, and mature deer after grazing pasture topdressed with copper (Cu) at two rates of application of copper sulphate (CuSO4(.)5H2O), and following oral administration of copper oxide (CuO) wire particles to some of the deer. In mid-March 2000 (Year 1), 1.1-ha paddocks (two/treatment) of ryegrass/white clover pasture received either 0 (Control), 6 (Low) or 12 (High) kg CuSO4(.)5H2O /ha applied with 250 kg potash superphosphate/ha. They were grazed by 4-month-old red deer hinds (n=11/treatment) from mid-April 2000 until early March 2001. In mid-March 2001 (Year 2), the pastures were topdressed again as for Year 1, and the original hinds, now yearlings which had grazed as a single group between studies, were returned to their respective treatments in mid-April 2001 and remained on the trial until mid-March 2002. They were mated during April/May. The pastures were also grazed by pregnant mature hinds (n=8/treatment) from mid-May 2001. As the Cu status (i.e. liver Cu concentration) of the yearling hinds on the pasture treated with 6 kg CuSO4(.)5H2O/ha was not significantly different from the untreated animals, in late July 2001 the yearling and mature deer on this treatment were treated orally with 10 g CuO wire particles. The mature hinds calved in November and the yearling hinds in December. Pasture samples were collected at about monthly intervals to determine concentrations of Cu and other minerals. In Year 1, liver biopsies and blood samples were collected at 4-6-weekly intervals for determination of Cu concentrations. In Year 2, samples were collected similarly at 6-12-weekly intervals. Liver biopsies and blood were also collected from progeny, along with milk from their dams. Liveweights were determined at 3-7-monthly intervals, as well as data on calving/mortality rates. Pasture Cu concentrations before the application of CuSO4(.)5H2O were 6-9 mg Cu/kg dry matter (DM) and

  13. Parentage assignment of progeny in mixed milt fertilization of ...

    African Journals Online (AJOL)

    Parentage of a stock of mixed milt produced progeny in current artificial breeding protocol of endangered Caspian brown trout, Salmo trutta caspius, was determined using three microsatellite loci chosen after a primary analysis of genetic diversity at nine microsatellite loci in the eight used breeder individuals. Overall ...

  14. Lung Deposition And Biological Effects Of Inhaled Radon Progenies

    International Nuclear Information System (INIS)

    Balashazy, I.; Farkas, A.; Szoke, I.; Moustafa, M.; Kudela, G.

    2010-01-01

    Inhaled radon progenies provide more than the half of natural radiation exposure. There is increasing evidence that the cellular distribution of radiation burden is an important factor regarding the biological response to ionisation radiation, thus, one of our tasks was the characterisation of the distribution of cellular exposure. Histological studies of former uranium miners presented strong correlation between primer deposition hot spots and neoplastic lesions. Most of these lesions were located along the carinal regions of the large bronchial airways. In the present work, computational fluid dynamics (CFD) approaches have been applied to simulate the deposition distribution of inhaled radon progenies along central human airways. The geometry and the cellular structure of epithelial lung tissue were numerically reconstructed based on anatomical and histological data. Single and multiple ha-hit and cellular dose distributions have been computed applying Monte Carlo modelling techniques at different breathing conditions. Figure 1. Deposition enhancement factor (EF) of inhaled radon progenies on a central airway bifurcation in airway generations 4-5 during light physical activity breathing condition. Size of scanning surface element is a 45μm side triangle. Left panel: EF max=1400,Dp=200 nm (attached). Right panel: EF max1290, Dp= 1 nm (unattached). Values of local per average deposition densities, that is, enhancement factors (Figure 1), hit probabilities and doses may be up to two-three orders of magnitude higher in the deposition hot spots than the average values. Dose calculations revealed that some cell clusters may receive high doses even at low exposure conditions. Applying the model to different radiation exposure conditions useful relations can be received regarding the linear-non threshold hypothesis

  15. Measurement of size distribution for 220Rn progeny attached aerosols

    International Nuclear Information System (INIS)

    Zhang Lei; Guo Qiuju; Zhuo Weihai

    2008-01-01

    The size distribution of radioactive aerosols is a very important factor for evaluating the inner exposure dose contributed by radon and thoron progeny in environments. In order to measure the size distribution of thoron progeny attached radioactive aerosols, a device was developed using wire screens. The count median diameter (CMD) and the geometric standard deviation (GSD) of attached radioactive aerosols were calculated by collecting ThB and using CR-39 as detector. Field measurement results at Yangjiang City in Guangdong Province show that the CMDs distribute between 30 and 130 nm, and the GSDs are between 1.9 and 3.3. It also shows that the more humid country, the smaller CMDs, and the ventilation has great influence on the size distribution of aerosols. The CMDs of adobe house are smaller than that of the concrete houses. (authors)

  16. Atmospheric concentrations of 7Be, 10Be and 210Pb in northeast Asia

    International Nuclear Information System (INIS)

    Yamagata, T.; Tada, W.; T saito; Nagai, H.; Murayama, M.; Momoshima, N.; Matsuzaki, H.

    2005-01-01

    Cosmogenic nuclides 7 Be (T 1/2 = 53.3 d) and 10 Be (T 1/2 = 1.5 X 10 6 y) are very useful tracer for the aerosols originated in the upper atmosphere, In the case of 10 Be in surface air, however, two components from upper troposphere and from re-suspended dust from soil are mixed. We try to divide these sources, in order to know an interpretation of aerosol drives. To try to separate the two different source of 10 Be, we use 210 Pb (T 1/2 = 22.3y), progeny of 222 Rn, as continental component. In this study, the distribution of these nuclides in aerosols collected in the Northwest pacific and adjacent seas by employing the research Vessels as cut off the re-suspended dusts from soil are reported. Since research expeditions are mostly short term, continuous observation is very difficult. So we observed at Tokyo and Hachijo-Island, remote island located 300 km south from Tokyo, in 2002-2004. Seasonal variations for 7 Be, 10 Be and 210 Pb concentration were similar pattern at Tokyo and Hachijo-Island. The concentrations were high in April and October to November and low in July to August. Although 210 Pb concentration showed the seasonal variation similar to 7 Be concentration, the average 210 Pb concentration of Tokyo showed the value high about 35% as compared with Hachijo-Island, while the average 7 Be concentration having been mostly in agreement at both points. For the distribution of these nuclide, 7 Be and 10 Be concentrations in ocean air showed strong latitude dependence but 210 Pb concentration depend on distance from continent.

  17. Milk production and composition, and progeny performance in young ewes with high merit for rapid growth and muscle and fat accumulation.

    Science.gov (United States)

    Rosales Nieto, C A; Ferguson, M B; Macleay, C A; Briegel, J R; Wood, D A; Martin, G B; Bencini, R; Thompson, A N

    2018-02-26

    In ewe lambs, acceleration of growth and accumulation of both muscle and fat leads to earlier sexual maturity and better reproductive performance. The next stage in the development of this theme is to test whether these aspects of growth in young ewes affect milk production in their first lactation and the growth of their first progeny. We studied 75 young Merino ewes that had known phenotypic values for depth of eye muscle (EMD) and fat (FAT), and known Australian Sheep Breeding Values for post-weaning weight (PWT) and depths of eye muscle (PEMD) and fat (PFAT). They lambed for the first time at 1 year of age. Their lambs were weighed weekly from birth to weaning at 10 weeks to determine live weight gain and weaning weight. Progeny birth weight was positively associated with live weight gain and weaning weight (P0.05). The PWT of the sire was positively associated with live weight gain (P0.05). The concentrations of fat, protein, lactose and total solids in the milk were not affected by the phenotype or genotype of the mothers or of the sires of the mothers, or by the sex of the progeny (P>0.05). We conclude that selection of young Merino ewes for better growth, and more rapid accumulation of muscle and fat, will lead to progeny that are heavier at birth, grow faster and are heavier at weaning. Moreover, milk production and composition do not seem to be affected by the genetic merit of the mother for post-weaning live weight or PEMD or PFAT. Therefore, Merino ewes can lamb at 1 year of age without affecting the production objectives of the Merino sheep industry.

  18. Lung dosimetry for inhaled radon progeny in smokers

    International Nuclear Information System (INIS)

    Baias, P. F.; Hofmann, W.; Winkler-Heil, R.; Cosma, C.; Duliu, O. G.

    2010-01-01

    Cigarette smoking may change the morphological and physiological parameters of the lung. Thus the primary objective of the present study was to investigate to what extent these smoke-induced changes can modify deposition, clearance and resulting doses of inhaled radon progeny relative to healthy non-smokers (NSs). Doses to sensitive bronchial target cells were computed for four categories of smokers: (1) Light, short-term (LST) smokers, (2) light, long-term (LLT) smokers, (3) heavy, short-term (HST) smokers and (4) heavy, long-term (HLT) smokers. Because of only small changes of morphological and physiological parameters, doses for the LST smokers hardly differed from those for NSs. For LLT and HST smokers, even a protective effect could be observed, caused by a thicker mucus layer and increased mucus velocities. Only in the case of HLT smokers were doses higher by about a factor of 2 than those for NSs, caused primarily by impaired mucociliary clearance, higher breathing frequency, reduced lung volume and airway obstructions. These higher doses suggest that the contribution of inhaled radon progeny to the risk of lung cancer in smokers may be higher than currently assumed on the basis of NS doses. (authors)

  19. Measurement of radon and thoron progeny size distributions and dose assessments at the mineral treatment industry in Thailand

    International Nuclear Information System (INIS)

    Chutima Kranrod; Supitcha Chanyotha; Nares Chankow

    2013-01-01

    A new portable type cascade impactor has been developed to determine the activity size distribution of radon and thoron progeny in a natural environment more efficiently. The modified impactor consists of 4 stages with a back up filter stage for the collection of aerosol samples. The aerosol cut points in the impactor are set for 10, 2.5, 1 and 0.5 μm at a flow rate of 4 L min -1 . Five CR-39 chips were used as alpha detectors for each stage. In order to separate α particles emitted from radon and thoron progeny, CR-39 detectors are covered with aluminum-vaporized Mylar films. The thickness of each film is adjusted to allow α particles emitted from radon and thoron progeny to reach the CR-39 detectors. The technique has been successfully tested in field studies, particularly inside a mineral treatment industry in Thailand to estimate doses in the working environment. The dose calculations by lung dose evaluation program showed that activity median aerodynamic diameters played a significant role in determining the particle size distributions of the attached radon and thoron progeny. The dose conversion factor determined from short term measurements due to exposure from the inhalation of thoron and its progeny was found to be 4 times higher than comparable values for radon and its progeny. The effective dose for workers exposed to radon is about 4-6 times higher than thoron. (author)

  20. Effect of Organic Selenium from Se-enriched Alga (Chlorella spp. on Selenium Transfer from Sows to Their Progeny

    Directory of Open Access Journals (Sweden)

    Martin Svoboda

    2009-01-01

    Full Text Available The study was conducted to determine the efficacy of organic Se from Se-enriched alga Chlorella spp. in placental transfer to piglets. In group A (n = 8 the sows were fed during the gestation a diet supplemented with inorganic Se (sodium selenite, 0.3 mg/kg. In group B (n = 8 the diet of the sows was supplemented with organic Se from Se-enriched alga (0.3 mg/kg. The Se concentrations in the whole blood (P P Chlorella spp. in sows resulted in greater transfer of Se to their progeny.

  1. Genotypic and environmental variation in chromium, cadmium and lead concentrations in rice.

    Science.gov (United States)

    Zeng, Fanrong; Mao, Ying; Cheng, Wangda; Wu, Feibo; Zhang, Guoping

    2008-05-01

    Genotypic and environmental variation in Cr, Cd and Pb concentrations of rice grains and the interaction between these metals were investigated by using 138 rice genotypes grown in three contaminated soils. There were significant genotypic differences in the three heavy metal concentrations of rice grains, with the absolute difference among 138 genotypes in grain Cr, Cd and Pb concentrations being 24.5-, 9.1- and 23.8-folds, respectively, under the slightly contaminated soil (containing 4.61mgkg(-1) Cr, 1.09mgkg(-1) Cd and Pb 28.28mgkg(-1), respectively). A highly significant interaction occurred between genotype and environment (soil type) in the heavy metal concentrations of rice grains. Cr concentration in rice grains was not correlated with Cd and Pb concentration. However, there was a significant correlation between Cd and Pb in slightly and highly contaminated soils. The results suggest the possibility to develop the rice cultivars with low Cd and Pb concentrations in grain.

  2. Radioactivity on the surfaces of computer monitors and television screens due to progeny palatal

    International Nuclear Information System (INIS)

    Abdel-Nady, A.; Morsy, A.A.

    2002-01-01

    Computer monitors and television screens can collect radon progeny. Radon decay forming meta-stable progeny, namely, Po-218, Po-214, and Po-210, which are found mostly in positively, charged aerosol particles. These particles are attract by the large negative field of a video display terminals (VDT) leading to buildup of radioactivity on the VDT screen. The charged aerosol particles might drift in the electric field between the VDT and the operator and be accelerated into the operator's face. The aim of this work is to measure these phenomena set of ultra-sensitive TASTRAK detectors used to measure the plate out of positively charged radioactive radon progeny. The track detectors were fixed on the outer monitor screen. For an occupational computer worker spending 200 days per year for 6 hours a day. It was found that the mean dose equivalent was 1.77 mSv, 0.25 mSv/year for normal CRT and LCD monitors respectively

  3. The study of triploid progenies crossed between different ploidy ...

    African Journals Online (AJOL)

    The study of triploid progenies crossed between different ploidy grapes. L Sun, G Zhang, A Yan, H Xu. Abstract. The cross between different ploidy grape was one of the effective ways to obtain new seedless cultivars, in this study, through testing the changes of the ovule weight and observing its anatomical structure, the ...

  4. Autumn frost hardiness in Norway spruce plus tree progeny and trees of the local and transferred provenances in central Sweden.

    Science.gov (United States)

    Hannerz, Mats; Westin, Johan

    2005-09-01

    Reforestation with provenances from locations remote from the planting site (transferred provenances) or the progeny of trees of local provenances selected for superior form and vigor (plus trees) offer alternative means to increase yield over that obtained by the use of seed from unselected trees of the local provenance. Under Swedish conditions, Norway spruce (Picea abies (L.) Karst.) of certain transferred provenances generally has an advantage in productivity relative to the local provenance comparable to that of progeny of plus trees. The aim of this study was to explore the extent to which productivity gains achieved by provenance transfer or the use of plus tree progeny are associated with reductions in autumn frost hardiness, relative to that of trees of the local provenance. In a field trial with 19-year-old trees in central Sweden, bud hardiness was tested on four occasions during the autumn of 2002. Trees of the local provenance were compared with trees of a south Swedish provenance originating 3 degrees of latitude to the south, a Belarusian provenance and the progeny of plus trees of local origin. The Belarusian provenance was the least hardy and the local provenance the most hardy, with plus tree progeny and the south Swedish provenance being intermediate in hardiness. Both the Belarusian provenance and the plus tree progeny were significantly taller than trees of the other populations. Within provenances, tree height was negatively correlated with autumn frost hardiness. Among the plus tree progeny, however, no such correlation between tree height and autumn frost hardiness was found. It is concluded that although the gain in productivity achieved by provenance transfer from Belarus was comparable to that achieved by using the progeny of plus trees of the local provenance, the use of trees of the Belarus provenance involved an increased risk of autumn frost damage because of later hardening.

  5. Experimental determination of the absorption rate of unattached radon progeny from respiratory tract to blood

    International Nuclear Information System (INIS)

    Butterweck, G.; Schuler, Ch.; Vessl, G.; Mueller, R.; Marsh, J.W.; Thrift, S.; Birchall, A.

    2002-01-01

    An exposure methodology was developed for the determination of the absorption rate of unattached radon progeny deposited in the human respiratory tract to blood. Twenty-one volunteers were exposed in a radon chamber during well-controlled aerosol and radon progeny conditions, with predominantly unattached radon daughters. Special efforts were made to restrict the dose to the volunteers to an absolute maximum of 0.08 mSv. Measurements of radon gas and radon progeny in blood samples of these volunteers indicated absorption half times of 20 min to 60 min. Former determinations, mainly performed with much larger aerosol particles of diameters between 100 nm and 1000 nm, implied absorption half times around 10 h. This indicates that the absorption of radon decay products from ciliated airways into blood is dependent upon particle size and particle composition. (author)

  6. Influence of Meteorological Conditions in the Annual Variation of Environmental Radon Activity

    International Nuclear Information System (INIS)

    Márquez, J.L.; Sáez, J.C.; Álvarez, A.; Quiñones, J.

    2015-01-01

    The aim of this study is to determine the correlations that exist between Rn gas, the Rn progeny and the meteorological variables. Also it takes part from the study to observe which variables are responsible of ambient dose equivalent rate variations. The study of correlations between different variables was performed using two methodologies; the first of them is a graphical representation of all variables to observe the temporal evolution of each variable and the second is the application of a Principal Component Analysis. The study of variables behavior has been divided into three periods (day, month and year), considering the presence and absence of rainfall for daily and monthly period. Several correlations have been identified between the Rn gas, Rn progeny and meteorological variables. It has also identified the influence of rainfall on the ambient dose equivalent rate due to the radon progeny. To complete the study, a theoretical model based on an adjustment by the least-squares has been performed to estimate the levels of exhaled radon in atmosphere for any day of the year.

  7. REPRODUCTIVE SYSTEM AND POLLEN FLOW IN PROGENIES OF Qualea grandiflora Mart., A TYPICAL SPECIES OF THE BRAZILIAN CERRADO

    Directory of Open Access Journals (Sweden)

    Lia Maris Orth Ritter Antiqueira

    2015-04-01

    Full Text Available This study analyzed the reproductive system and the pollen dispersion pattern of Qualea grandiflora progenies. This is a typical species from the Brazilian Cerrado about which there are not too many studies from the genetics point of view. The study was conducted in an area of 2.2 hectares located in the Conservation Unit managed by the Forest Institute of the state of São Paulo, Brazil (Assis State Forest. Total genomic DNA of 300 seeds from 25 plants (12 seeds from each plant was extracted and amplified using specific primers to obtain microsatellite markers. Results showed that selfing is frequent among adults and progenies, and the species reproduces by outcrossing between related and unrelated individuals (0.913. The single-locus outcrossing rate was 0.632, which indicates that mating between unrelated individuals is more frequent than between related plants. The selfing rate was low (0.087, that is, the species is allogamous and self-fertilization is reduced. About 35% of the plants in the progenies were full-sibs, and about 57%, half-sibs. Besides, about 8% of the progenies were selfing siblings. The genetic differentiation coefficient within progenies was 0.139, whereas the fixation rate was about 27%. The estimate of the effective size revealed that the genetic representativeness of descent was lower than expected in random mating progenies: The analyzed samples corresponded to only 13.2 individuals of an ideal panmictic population. In environmental recovery programs, seeds, preferably from different fruits, should be collected from 95 trees to preserve the genetic diversity of the species.

  8. Variation among chlorine concentration ratios for native and agronomic plants

    International Nuclear Information System (INIS)

    Sheppard, S.C.; Evenden, W.G.; Macdonald, C.R.

    1999-01-01

    Variation among plant/soil concentration ratios (CRs) for important radionuclides requires attention because it is a major source of uncertainty in nuclear environmental safety assessments. For agronomic plants, variation among plant species is easy to deal with because there are relatively few species. In natural settings, there are vastly more species and the question becomes how to develop representative statistical distributions of CRs. Chlorine (Cl) is a good element with which to address this problem, because 36 Cl is a key radionuclide in nuclear waste disposal and yet stable Cl is easily measured in the environment. We measured CRs (dry weight basis) for Cl among edible parts of agronomic plants at one site, and found a geometric mean (GM) of 10, a geometric standard deviation (GSD) of 1.9 and a range of 5-66. When the GM was weighted by the relative contributions of the various plants to the human diet, it rose to 16. Among native plants at five sites, each site representative of a specific environment, the GMs were 4.0-13 and the GSDs were 2.9-6.2. The CRs for individual species ranged from 0.8 to 170. However, when weighted by relative contributions of the plants to selected animal diets, the GMs were as high as 50. The conclusions are that: the variation in CR for agronomic plants is a subset of the variation among native or all plants, variation among species (the GSD) can be sixfold, and variation among species is large enough that typical diets of specific animals could expose them to several-fold higher amounts of Cl (or 36 Cl) than expected from generic CR values. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  9. Genotypic and environmental variation in chromium, cadmium and lead concentrations in rice

    International Nuclear Information System (INIS)

    Zeng Fanrong; Mao Ying; Cheng Wangda; Wu Feibo; Zhang Guoping

    2008-01-01

    Genotypic and environmental variation in Cr, Cd and Pb concentrations of rice grains and the interaction between these metals were investigated by using 138 rice genotypes grown in three contaminated soils. There were significant genotypic differences in the three heavy metal concentrations of rice grains, with the absolute difference among 138 genotypes in grain Cr, Cd and Pb concentrations being 24.5-, 9.1- and 23.8-folds, respectively, under the slightly contaminated soil (containing 4.61 mg kg -1 Cr, 1.09 mg kg -1 Cd and Pb 28.28 mg kg -1 , respectively). A highly significant interaction occurred between genotype and environment (soil type) in the heavy metal concentrations of rice grains. Cr concentration in rice grains was not correlated with Cd and Pb concentration. However, there was a significant correlation between Cd and Pb in slightly and highly contaminated soils. The results suggest the possibility to develop the rice cultivars with low Cd and Pb concentrations in grain. - Some rice genotypes had consistently low grain Cr, Cd and Pb concentrations under the soil with differently contaminated levels

  10. Possible causes of variation in acrylamide concentration in French fries prepared in food service establishments: an observational study.

    Science.gov (United States)

    Sanny, M; Jinap, S; Bakker, E J; van Boekel, M A J S; Luning, P A

    2012-05-01

    Acrylamide is a probable human carcinogen, and its presence in a range of fried and oven-cooked foods has raised considerable health concern world-wide. Dietary intake studies observed significant variations in acrylamide concentrations, which complicate risk assessment and the establishment of effective control measures. The objective of this study was to obtain an insight into the actual variation in acrylamide concentrations in French fries prepared under typical conditions in a food service establishment (FSE). Besides acrylamide, frying time, frying temperature, and reducing sugars were measured and the actual practices at receiving, thawing and frying during French fries preparation were observed and recorded. The variation in the actual frying temperature contributed most to the variation in acrylamide concentrations, followed by the variation in actual frying time; no obvious effect of reducing sugars was found. The lack of standardised control of frying temperature and frying time (due to inadequate frying equipment) and the variable practices of food handlers seem to contribute most to the large variation and high acrylamide concentrations in French fries prepared in a restaurant type of FSE as compared to chain fast-food services, and institutional caterers. The obtained insights in this study can be used to develop dedicated control measures in FSE, which may contribute to a sustainable reduction in the acrylamide intake. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Variations of leaf N and P concentrations in shrubland biomes across northern China: phylogeny, climate, and soil

    Science.gov (United States)

    Yang, Xian; Chi, Xiulian; Ji, Chengjun; Liu, Hongyan; Ma, Wenhong; Mohhammat, Anwar; Shi, Zhaoyong; Wang, Xiangping; Yu, Shunli; Yue, Ming; Tang, Zhiyao

    2016-08-01

    Concentrations of leaf nitrogen (N) and phosphorus (P) are two key traits of plants for ecosystem functioning and dynamics. Foliar stoichiometry varies remarkably among life forms. However, previous studies have focused on the stoichiometric patterns of trees and grasses, leaving a significant knowledge gap for shrubs. In this study, we explored the intraspecific and interspecific variations of leaf N and P concentrations in response to the changes in climate, soil property, and evolutionary history. We analysed 1486 samples composed of 163 shrub species from 361 shrubland sites in northern China encompassing 46.1° (86.7-132.8° E) in longitude and 19.8° (32.6-52.4° N) in latitude. Leaf N concentrations decreased with precipitation, while leaf P concentrations decreased with temperature and increased with precipitation and soil total P concentrations. Both leaf N and P concentrations were phylogenetically conserved, but leaf P concentrations were less conserved than leaf N concentrations. At the community level, climate explained more interspecific variation of leaf nutrient concentrations, while soil nutrients explained most of the intraspecific variation. These results suggested that leaf N and P concentrations responded to climate, soil, and phylogeny in different ways. Climate influenced the community chemical traits through the shift in species composition, whereas soil directly influenced the community chemical traits. New patterns were discovered using our observations on specific regions and vegetation types, which improved our knowledge of broad biogeographic patterns of leaf chemical traits.

  12. Variation in acrylamide concentration in French fries : effects of control measures in food service establishments

    NARCIS (Netherlands)

    Sanny, M.A.I.

    2012-01-01

    The aim of this thesis was first to identify the major technological and managerial factors and to investigate their contribution to variation in acrylamide concentrations. The second aim was to investigate the effect of technological and managerial control measures on the concentration and

  13. Variation of dissolved organic nitrogen concentration during the ultrasonic pretreatment to Microcystis aeruginosa.

    Science.gov (United States)

    Liu, Cheng; Wang, Jie; Cao, Zhen; Chen, Wei; Bi, Hongkai

    2016-03-01

    Algae cells were the main sources of dissolved organic nitrogen (DON) in raw water with plenty of algae, and ultrasonic pretreatment was one of the algae-controlling methods through the damage of algae cells. However, the variation of DON concentration during the ultrasonic treatment process was not confirmed. Variation of DON concentration during the processes of low frequency ultrasound treatment of Microcystis aeruginosa was investigated. In addition, the effect of sonication on the metabolite concentration, algae cellar activity and the subsequent coagulation performance were discussed. The results showed that after a long duration of ultrasonic (60 s), nearly 90% of the algal cells were damaged and the maximum concentration of DON attained more than 3 mg/L. In order to control the leakage extent of DON, the sonication time should be less than 30 s with power intensity of more than 1.0 W/cm(3). In the mean time, ultrasonic treatment could inhibit the reactivation and the proliferation of algal, keep the algae cell wall integrity and enhance coagulation effectively under the same condition. However, ultrasound frequency had little effect on DON at the frequency range used in this study (20-150 kHz). Copyright © 2015 Elsevier B.V. All rights reserved.

  14. The effect of pollen source vs. flower type on progeny performance and seed predation under contrasting light environments in a cleistogamous herb.

    Science.gov (United States)

    Munguía-Rosas, Miguel A; Campos-Navarrete, María J; Parra-Tabla, Víctor

    2013-01-01

    Dimorphic cleistogamy is a specialized form of mixed mating system where a single plant produces both open, potentially outcrossed chasmogamous (CH) and closed, obligately self-pollinated cleistogamous (CL) flowers. Typically, CH flowers and seeds are bigger and energetically more costly than those of CL. Although the effects of inbreeding and floral dimorphism are critical to understanding the evolution and maintenance of cleistogamy, these effects have been repeatedly confounded. In an attempt to separate these effects, we compared the performance of progeny derived from the two floral morphs while controlling for the source of pollen. That is, flower type and pollen source effects were assessed by comparing the performance of progeny derived from selfed CH vs. CL and outcrossed CH vs. selfed CH flowers, respectively. The experiment was carried out with the herb Ruellia nudiflora under two contrasting light environments. Outcrossed progeny generally performed better than selfed progeny. However, inbreeding depression ranges from low (1%) to moderate (36%), with the greatest value detected under shaded conditions when cumulative fitness was used. Although flower type generally had less of an effect on progeny performance than pollen source did, the progeny derived from selfed CH flowers largely outperformed the progeny from CL flowers, but only under shaded conditions and when cumulative fitness was taken into account. On the other hand, the source of pollen and flower type influenced seed predation, with selfed CH progeny the most heavily attacked by predators. Therefore, the effects of pollen source and flower type are environment-dependant and seed predators may increase the genetic differences between progeny derived from CH and CL flowers. Inbreeding depression alone cannot account for the maintenance of a mixed mating system in R. nudiflora and other unidentified mechanisms must thus be involved.

  15. The effect of pollen source vs. flower type on progeny performance and seed predation under contrasting light environments in a cleistogamous herb.

    Directory of Open Access Journals (Sweden)

    Miguel A Munguía-Rosas

    Full Text Available Dimorphic cleistogamy is a specialized form of mixed mating system where a single plant produces both open, potentially outcrossed chasmogamous (CH and closed, obligately self-pollinated cleistogamous (CL flowers. Typically, CH flowers and seeds are bigger and energetically more costly than those of CL. Although the effects of inbreeding and floral dimorphism are critical to understanding the evolution and maintenance of cleistogamy, these effects have been repeatedly confounded. In an attempt to separate these effects, we compared the performance of progeny derived from the two floral morphs while controlling for the source of pollen. That is, flower type and pollen source effects were assessed by comparing the performance of progeny derived from selfed CH vs. CL and outcrossed CH vs. selfed CH flowers, respectively. The experiment was carried out with the herb Ruellia nudiflora under two contrasting light environments. Outcrossed progeny generally performed better than selfed progeny. However, inbreeding depression ranges from low (1% to moderate (36%, with the greatest value detected under shaded conditions when cumulative fitness was used. Although flower type generally had less of an effect on progeny performance than pollen source did, the progeny derived from selfed CH flowers largely outperformed the progeny from CL flowers, but only under shaded conditions and when cumulative fitness was taken into account. On the other hand, the source of pollen and flower type influenced seed predation, with selfed CH progeny the most heavily attacked by predators. Therefore, the effects of pollen source and flower type are environment-dependant and seed predators may increase the genetic differences between progeny derived from CH and CL flowers. Inbreeding depression alone cannot account for the maintenance of a mixed mating system in R. nudiflora and other unidentified mechanisms must thus be involved.

  16. Preliminary results on variations of radon concentration associated with rock deformation in a uranium mine

    Science.gov (United States)

    Verdoya, Massimo; Bochiolo, Massimo; Chiozzi, Paolo; Pasquale, Vincenzo; Armadillo, Egidio; Rizzello, Daniele; Chiaberto, Enrico

    2013-04-01

    Time-series of radon concentration and environmental parameters were recently recorded in a uranium mine gallery, located in the Maritime Alps (NW Italy). The mine was bored in metarhyolites and porphyric schists mainly composed by quartz, feldspar, sericite and fluorite. U-bearing minerals are generally concentrated in veins heterogeneously spaced and made of crystals of metaautunite and metatorbernite. Radon air concentration monitoring was performed with an ionization chamber which was placed at the bottom of the gallery. Hourly mean values of temperature, pressure, and relative humidity were also measured. External data of atmospheric temperature, pressure and rainfall were also available from a meteorological station located nearby, at a similar altitude of the mine. The analysis of the time series recorded showed variation of radon concentration, of large amplitude, exhibiting daily and half-daily periods, which do not seem correlated with meteorological records. Searching for the origin of radon concentration changes and monitoring their amplitude as a function of time can provide important clues on the complex emanation process. During this process, radon reaches the air- and water-filled interstices by recoil and diffusion, where its migration is directed towards lower concentration regions, following the local gradient. The radon emanation from the rock matrix could also be controlled by stress changes acting on the rate of migration of radon into fissures, and fractures. This may yield emanation boosts due to rock extension and the consequent crack broadening, and emanation decrease when joints between cracks close. Thus, besides interaction and mass transfer with the external atmospheric environment, one possible explanation for the periodic changes in radon concentrations in the investigated mine, could be the variation of rock deformation related to lunar-solar tides. The large variation of concentration could be also due to the fact that the mine is

  17. Feeding broiler breeder males. 4. Deficient feed allocation reduces fertility and broiler progeny body weight.

    Science.gov (United States)

    Romero-Sanchez, H; Plumstead, P W; Leksrisompong, N; Brannan, K E; Brake, J

    2008-04-01

    Two experiments were conducted to evaluate the effects of male broiler breeder feed intake on broiler progeny performance. In experiment 1, a low cumulative nutrition program supplied 29,580 kcal of ME and 1,470 g of CP, whereas a high cumulative nutrition program supplied 33,500 kcal of ME and 1,730 g of CP to photostimulation at 21 wk of age. Two diets (HiDiet and LoDiet) were formulated, and a single feeding program was used to achieve the selected nutrient intakes. The HiDiet group of males in experiment 1 achieved greater BW and exhibited lower fertility when fed as the LoDiet males from the onset of egg production. The HiDiet breeder males subsequently produced male broilers from eggs laid at 29 wk of age that exhibited lower BW at 42 d. This was due to the heaviest 50% of the breeder males in this treatment not gaining BW consistently due to less-than-adequate ME intake relative to their greater BW requirements. Two feeding programs during the production period (constant or increasing) were compared in experiment 2. Broilers were hatched from eggs laid at 32 and 48 wk of age to evaluate the vertical effect of male treatments on progeny performance. No difference in fertility or broiler performance was found at 32 wk. However, the constant feeding program produced lower fertility from 36 to 55 wk of age, and this resulted in a lower male and female broiler progeny BW at 42 d of age from eggs collected at 48 wk of age. Adequate breeder male feed allocation during the production period improved fertility and favorably affected broiler progeny performance in both experiments. However, broiler progeny effects were observed only when there were differences in fertility, which suggests that the males with the greatest genetic potential were not mating at these times.

  18. Prevention of inclusion body hepatitis/hydropericardium syndrome in progeny chickens by vaccination of breeders with fowl adenovirus and chicken anemia virus.

    Science.gov (United States)

    Toro, H; González, C; Cerda, L; Morales, M A; Dooner, P; Salamero, M

    2002-01-01

    The hypothesis that an effective protection of progeny chickens against inclusion body hepatitis/hydropericardium syndrome (IBH/HP) can be achieved by dual vaccination of breeders with fowl adenovirus (FAV) serotype 4 and chicken anemia virus (CAV) was tested. Thus, 17-wk-old brown leghorn pullet groups were vaccinated by different schemes including single FAV (inactivated), single CAV (attenuated), FAV and CAV dually, or were not vaccinated (controls). Subsequent progenies of these breeders were challenged with the virulent strains FAV-341 and CAV-10343 following three strategies: 1) FAV-341 intramuscularly (i.m.) at day 10 of age (only FAV-vaccinated and control progenies); 2) FAV + CAV i.m. simultaneously at day 10 of age (all progenies); 3) CAV i.m. at day 1 and FAV orally at day 10 of age (all progenies). The induction of IBH/HP in these progenies was evaluated throughout a 10-day period. Both breeder groups vaccinated against FAV and those vaccinated against CAV increased virus neutralizing specific antibodies. Challenge strategy 1 showed 26.6% mortality in control progeny chickens and 13.3% in the progeny of FAV-vaccinated breeders. Presence of lesions in the liver of these groups showed no significant differences (P > 0.05), suggesting a discreet protective effect of the vaccine. Challenge strategy 2 showed 29.4% mortality in controls and 94% of chickens showed hepatic inclusion bodies (HIB). Single CAV vaccination of breeders did not demonstrate a beneficial effect, with both mortality and liver lesions resembling the nonvaccinated controls. FAV vaccination of breeders significantly reduced both mortality (7.4%) and liver lesions (26% HIB) (P vaccination of breeders with FAV and CAV proved to be necessary to achieve maximum protection of the progeny (no mortality and 7% HIB). Challenge strategy 3 produced no mortality but consistent liver damage in controls (96% HIB). In this case, both CAV and FAV + CAV-vaccinated breeders showed best protection results

  19. Past as Prologue: Educational Psychology's Legacy and Progeny

    Science.gov (United States)

    Alexander, Patricia A.

    2018-01-01

    On the occasion of the 125th anniversary of the American Psychological Association, the legacies and progenies of the discipline of educational psychology are explored. To capture those legacies, transformational and influential contributions by educational psychologists to schools and society are described as key themes. Those themes entail: the…

  20. Temporal variations of atmospheric CO2 concentration in a temperate deciduous forest in central Japan

    International Nuclear Information System (INIS)

    Murayama, Shohei; Saigusa, Nobuko; Yamamoto, Susumu; Kondo, Hiroaki; Eguchi, Yozo; Chan, Douglas

    2003-01-01

    In order to examine the temporal variation of the atmospheric CO 2 concentration in a temperate deciduous forest, and its relationship with meteorological conditions, continuous measurements of CO 2 and meteorological parameters have been made since 1993 on a tower at Takayama in the central part of Japan. In addition to an average secular increase in atmospheric CO 2 of 1.8 ppm/yr, diurnal variation with a maximum during the night-time to early morning and a minimum in the afternoon is observed from late spring to early fall; the diurnal cycle is not so clearly observed in the remaining seasons of the year. A concentration difference between above and below the canopy, and its diurnal variation, can also be seen clearly in summer. Daily mean concentration data show a prominent seasonal cycle. The maximum and the minimum of the seasonal cycle occur in April and from mid August to mid September, respectively. Day-to-day changes in the diurnal cycle of CO 2 are highly dependent on the day-to-day variations in meteorological conditions. However, CO 2 variations on longer time scales (>10 d) appear to be linearly related to changes in respiration. At Takayama, variations in the 10-d standard deviation of daily mean CO 2 data and 10-d averaged respiration show distinct relationships with soil temperature during spring and fall seasons. In spring, respiration has a stronger exponential dependence on soil temperature than in fall. Interestingly, in summer when soil temperature becomes greater than about 15 deg C, biological respiration becomes more variable and independent of the soil temperature. Thus, at the Takayama site, the Q10 relationship is seasonally dependent, and does not represent well the biological respiration process when the soil temperature rises above 15 deg C

  1. Inherited sterility in progeny of irradiated male cotton leafworm, spodoptera littoralis (boisd)

    International Nuclear Information System (INIS)

    Sallam, H.A.

    1991-01-01

    Full grown male pupae of spodoptera littoralis were exposed to sub sterilizing doses of 7.5, 10, 12.5 or 15 krad of gamma radiation and mated with unirradiated females. In another trial, male pupae irradiated with 10 krad were crossed with unirradiated females, and their progeny were out crossed or inbred. In all cases, the effects of these treatments on some biological aspects in the resulting progeny for 3 generations were studied. Larval and pupal mortality were 21 to 53% and 5 to 30% higher than the normal among F 1 and F 2 , respectively. THE average developmental time from egg hatch to adult emergence was not affected and so, also sex ratio which seemed about normal.2 tab

  2. Inherited sterility in progeny of irradiated male cotton leafworm, spodoptera littoralis (boisd)

    Energy Technology Data Exchange (ETDEWEB)

    Sallam, H A

    1991-01-01

    Full grown male pupae of spodoptera littoralis were exposed to sub sterilizing doses of 7.5, 10, 12.5 or 15 krad of gamma radiation and mated with unirradiated females. In another trial, male pupae irradiated with 10 krad were crossed with unirradiated females, and their progeny were out crossed or inbred. In all cases, the effects of these treatments on some biological aspects in the resulting progeny for 3 generations were studied. Larval and pupal mortality were 21 to 53% and 5 to 30% higher than the normal among F[sub 1] and F[sub 2], respectively. THE average developmental time from egg hatch to adult emergence was not affected and so, also sex ratio which seemed about normal.2 tab.

  3. The seasonal variation of radon concentration in the atmosphere of Chichi-jima island in the pacific ocean

    International Nuclear Information System (INIS)

    Yoshioka, Katsuhiro

    2008-01-01

    We continuously measured the radon concentration from April 2001 to December 2004 in Chichi-jima Is. We expect that the radon concentration at Chichi-jima Is. would be influenced only by the air mass transported through the long distance. The hourly values had very large variations, ranging from 0.2 to 6.0 Bqm -3 . No diurnal periodicity was found in the variation of the radon concentration. We found that the monthly averages of the radon concentration had a clear long term pattern, showing the highest in the winter and the lowest in the summer. To analyze the radon long time variation, an arriving air mass is grouped into five sectors according to the backward trajectory. Sector I is the sea areas surrounding Chichi-jima Is. Sector II including Philippines, Indonesia and the southeast Asia is spread the southwestern Pacific Ocean from Chichi-jima Is. and sector V is spread the northeastern way to the southeast. Sector III includes China, Mongolia, Korea and the western Japan region and sector IV two regions of the eastern Siberia and the eastern Japan. The radon long time variation showed a high positive correlation between the number of arrivals of the continental air mass, while strong negative correlation between the maritime air mass. (author)

  4. The behavior of maize hybrids generated from contrasting progenies regarding the use of nitrogen

    Directory of Open Access Journals (Sweden)

    Fernando Lisboa Guedes

    2014-11-01

    Full Text Available The purpose of this study was to evaluate the performance of maize hybrids synthesized from contrasting genotypes with regard to the use of nitrogen that were selected for their performance in topcrosses. Sixty-seven S0:1 progenies derived from the germplasm bank of Ufla were evaluated in topcross combinations with two testers  at two nitrogen levels. The six progenies with the greatest tolerance and responsiveness to nitrogen (RT and the five with the least tolerance and responsiveness (RnTn were selected and, were, afterwards, crossed in a complete diallel, for a total of 55 hybrid combinations. The following genetic parameters were estimated: genetic variance among the hybrids (σ^2G, broad sense heritability in the mean of the hybrids, and selective accuracy (r^2gg. It was observed that the genetic parameters were greater in the environments with available nitrogen and that the early selection by performance in topcrosses of progenies tolerant to low N levels may not be made with high intensity. The hybrids tolerant to low N levels were obtained by crossing contrasting parents.

  5. Single Low-Dose Ionizing Radiation Induces Genotoxicity in Adult Zebrafish and its Non-Irradiated Progeny.

    Science.gov (United States)

    Lemos, J; Neuparth, T; Trigo, M; Costa, P; Vieira, D; Cunha, L; Ponte, F; Costa, P S; Metello, L F; Carvalho, A P

    2017-02-01

    This study investigated to what extent a single exposure to low doses of ionizing radiation can induce genotoxic damage in irradiated adult zebrafish (Danio rerio) and its non-irradiated F1 progeny. Four groups of adult zebrafish were irradiated with a single dose of X-rays at 0 (control), 100, 500 and 1000 mGy, respectively, and couples of each group were allowed to reproduce following irradiation. Blood of parental fish and whole-body offspring were analysed by the comet assay for detection of DNA damage. The level of DNA damage in irradiated parental fish increased in a radiation dose-dependent manner at day 1 post-irradiation, but returned to the control level thereafter. The level of DNA damage in the progeny was directly correlated with the parental irradiation dose. Results highlight the genotoxic risk of a single exposure to low-dose ionizing radiation in irradiated individuals and also in its non-irradiated progeny.

  6. Vesicular transport of progeny parvovirus particles through ER and Golgi regulates maturation and cytolysis.

    Science.gov (United States)

    Bär, Séverine; Rommelaere, Jean; Nüesch, Jürg P F

    2013-09-01

    Progeny particles of non-enveloped lytic parvoviruses were previously shown to be actively transported to the cell periphery through vesicles in a gelsolin-dependent manner. This process involves rearrangement and destruction of actin filaments, while microtubules become protected throughout the infection. Here the focus is on the intracellular egress pathway, as well as its impact on the properties and release of progeny virions. By colocalization with cellular marker proteins and specific modulation of the pathways through over-expression of variant effector genes transduced by recombinant adeno-associated virus vectors, we show that progeny PV particles become engulfed into COPII-vesicles in the endoplasmic reticulum (ER) and are transported through the Golgi to the plasma membrane. Besides known factors like sar1, sec24, rab1, the ERM family proteins, radixin and moesin play (an) essential role(s) in the formation/loading and targeting of virus-containing COPII-vesicles. These proteins also contribute to the transport through ER and Golgi of the well described analogue of cellular proteins, the secreted Gaussia luciferase in absence of virus infection. It is therefore likely that radixin and moesin also serve for a more general function in cellular exocytosis. Finally, parvovirus egress via ER and Golgi appears to be necessary for virions to gain full infectivity through post-assembly modifications (e.g. phosphorylation). While not being absolutely required for cytolysis and progeny virus release, vesicular transport of parvoviruses through ER and Golgi significantly accelerates these processes pointing to a regulatory role of this transport pathway.

  7. Seasonal variations of radon concentrations in single-family houses with different sub-structures

    DEFF Research Database (Denmark)

    Majborn, B.

    1992-01-01

    Seasonal variations of indoor radon concentrations have been studied in 70 single-family houses selected according to the type of sub-structure and the type of soil underneath the house. Five categories of sub-structure were included - slab-on-grade, crawl space, basement, and combinations...... of basement with slab-on-grade or crawl space. Half of the houses are located on clayey till and the other half on glaciofluvial gravel. In each house radon was measured in a living room and a bedroom, in the basement if present, and in the crawl space if present and accessible. The measurements were made...... with track detectors on a quarterly basis throughout a year. For living rooms and bedrooms the seasonal variations range from being highly significant for the slab-on-grade houses to being insignificant for the crawl space houses. For basements and crawl spaces the geometric mean radon concentrations do...

  8. Studies on radon concentration at the work places of Mysuru, Bengaluru, Tumkuru and Kolar Districts of Karnataka State, South India

    International Nuclear Information System (INIS)

    Ningappa, C.; Reddy, K. Umesha; Rangaswamy, D.R.; Sannappa, J.

    2015-01-01

    Radon is a radioactive noble gas and is the decay product of naturally occurring uranium. It decays into radioactive metal ions polonium-218 and polonium-214 by alpha radiation, which are harmful to the human health. The concentrations of radon and its progeny inside a given working place depends on activity of radium both in the soil surrounding the workplace and in the building materials, atmospheric conditions, design of the workplace, porosity of the surrounding soil, building layout, and the ventilation habits of the inhabitants of the building. The estimation of dose due to radon and its progeny to the general public and workers at work places are very important. Thus, concentration of radon and its progeny and dose due to radon and its progeny to the public and workers were measured at sixty workplaces of Mysuru, Bengaluru, Tumkur and Kolar districts based on geology and willingness of the workplace owner using twin cup dosimeter based on Solid State Nuclear Track Detectors (SSNTDs) and results are discussed in the present study. The values measured indoor radon in the area of study ranged from a 11.6 to 284.8 Bq.m -3 . (author)

  9. Experimental verification of the attachment theory of radon progeny onto ambient aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Tokonami, Shinji

    2000-01-01

    The attachment theory of radon progeny onto ambient aerosols was experimentally verified with a cascade impactor and a graded screen array at the EML environmental chamber. Monodisperse aerosols in the size range of 70 to 500 nm were generated with Carnauba wax by means of the evaporation-condensation method. The temperature and the relative humidity in the chamber were set at 20 C and 20%, respectively, throughout the entire experiment. When the aerosols were being injected into the chamber, both the number size distribution and the activity-weighted size distribution of attached radon progeny were stable. The activity-weighted size distribution was compared with the attachment rate distribution obtained by measuring the number size distribution with the SMPS and multiplying the size-dependent attachment coefficient. There was a relatively good agreement between the two distributions.

  10. Temporal variations of Escherichia coli concentrations in a large Midwestern river

    Science.gov (United States)

    Schilling, K.E.; Zhang, Y.-K.; Hill, D.R.; Jones, C.S.; Wolter, C.F.

    2009-01-01

    The Raccoon River used by the Des Moines Water Works to serve more than 400,000 people in central Iowa is threatened by contamination from Escherichia coli bacteria from point and nonpoint sources. The 9389 km2 watershed is highly agricultural, with 73% of the land in row crop production and widespread animal production. Results from 2155 grab samples from 1997 to 2005 for E. coli analysis were examined for temporal variations. E. coli concentrations were found to vary across years, seasons, and flow conditions, with a 9-year mean value of 1156 most probable number (MPN)/100 ml. Monthly concentrations exhibited clear seasonality with highest values in May through July. Although E. coli concentrations were higher during periods of greater discharge, the relation of log E. coli to log discharge was not particularly strong (r2 = 0.35). The variogram of E. coli concentrations showed temporal correlation within a span of 4 days suggesting that concentrations measured on 1 day may be related in time to concentrations measured up to 3 days later and beyond 4 days the concentrations vary randomly. The spectral analysis of the time series of E. coli was also carried out and was fitted well with the spectrum of an exponential covariance function. Deciphering temporal patterns and correlation of E. coli bacteria in streams may be useful for developing future monitoring strategies to track concentration patterns and loads. ?? 2008 Elsevier B.V. All rights reserved.

  11. Causes of seasonal variations of Cs-134/137 activity concentrations in surface air

    International Nuclear Information System (INIS)

    Hoetzl, H.; Winkler, R.

    1993-01-01

    In winter months maxima of Cs-134/137 activity concentrations in air are observed at several locations in Europe. To clarify this phenomenon, from October 1991 to November 1992 we performed a program for aerosol collection on a short-term scale based on collecting intervals of 48-72 hours. The local meteorological parameters were determined simultaneously. Statistical analysis of these observations reveiled a highly significant positive correlation between Cs-137 activity concentration and the so-called 'Stagnationsindex'. Based on this relationship the seasonal variations of Cs-134/137 concentrations in ground-level air can be explained by atmospheric inversion conditions frequently occurring during fall- and wintermonths. (orig.) [de

  12. Induced genetic variation for aluminum and salt tolerance in rice

    International Nuclear Information System (INIS)

    Chaudhry, M.A.; Yoshida, S.; Vegara, B.S.

    1989-01-01

    Full text: MNH applied to fertilized egg cells of 'Taichung 65' led to an increase in genetic variation in the progenies. Of a M 2 population of 15,000 seedlings, 2.3% were scored tolerant to salt. Tolerant plants showed less shoot and root growth inhibition. 50 variants expressed different degrees of tolerance to Al, even up to 30 ppm. The tolerance was related to longer root development. (author)

  13. Spatiotemporal variation of radon and carbon dioxide concentrations in an underground quarry: coupled processes of natural ventilation, barometric pumping and internal mixing

    International Nuclear Information System (INIS)

    Perrier, Frederic; Richon, Patrick

    2010-01-01

    Radon-222 and carbon dioxide concentrations have been measured during several years at several points in the atmosphere of an underground limestone quarry located at a depth of 18 m in Vincennes, near Paris, France. Both concentrations showed a seasonal cycle. Radon concentration varied from 1200 to 2000 Bq m -3 in summer to about 800-1400 Bq m -3 in winter, indicating winter ventilation rates varying from 0.6 to 2.5 x 10 -6 s -1 . Carbon dioxide concentration varied from 0.9 to 1.0% in summer, to about 0.1-0.3% in winter. Radon concentration can be corrected for natural ventilation using temperature measurements. The obtained model also accounts for the measured seasonal variation of carbon dioxide. After correction, radon concentrations still exhibit significant temporal variation, mostly associated with the variation of atmospheric pressure, with coupling coefficients varying from -7 to -26 Bq m -3 hPa -1 . This variation can be accounted for using a barometric pumping model, coupled with natural ventilation in winter, and including internal mixing as well. After correction, radon concentrations exhibit residual temporal variation, poorly correlated between different points, with standard deviations varying from 3 to 6%. This study shows that temporal variation of radon concentrations in underground cavities can be understood to a satisfactory level of detail using non-linear and time-dependent modelling. It is important to understand the temporal variation of radon concentrations and the limitations in their modelling to monitor the properties of natural or artificial underground settings, and to be able to assess the existence of new processes, for example associated with the preparatory phases of volcanic eruptions or earthquakes.

  14. Pre-disposition and epigenetics govern variation in bacterial survival upon stress.

    Directory of Open Access Journals (Sweden)

    Ming Ni

    Full Text Available Bacteria suffer various stresses in their unpredictable environment. In response, clonal populations may exhibit cell-to-cell variation, hypothetically to maximize their survival. The origins, propagation, and consequences of this variability remain poorly understood. Variability persists through cell division events, yet detailed lineage information for individual stress-response phenotypes is scarce. This work combines time-lapse microscopy and microfluidics to uniformly manipulate the environmental changes experienced by clonal bacteria. We quantify the growth rates and RpoH-driven heat-shock responses of individual Escherichia coli within their lineage context, stressed by low streptomycin concentrations. We observe an increased variation in phenotypes, as different as survival from death, that can be traced to asymmetric division events occurring prior to stress induction. Epigenetic inheritance contributes to the propagation of the observed phenotypic variation, resulting in three-fold increase of the RpoH-driven expression autocorrelation time following stress induction. We propose that the increased permeability of streptomycin-stressed cells serves as a positive feedback loop underlying this epigenetic effect. Our results suggest that stochasticity, pre-disposition, and epigenetic effects are at the source of stress-induced variability. Unlike in a bet-hedging strategy, we observe that cells with a higher investment in maintenance, measured as the basal RpoH transcriptional activity prior to antibiotic treatment, are more likely to give rise to stressed, frail progeny.

  15. The measurement of thoron (220Rn) concentration in indoor air continuously using pylon model WLx

    International Nuclear Information System (INIS)

    Hasnel Sofyan

    2011-01-01

    The concentration of thoron ( 220 Rn) in particular location can be higher than radon ( 220 Rn), however, its presence is always neglected. This might be due to the difficulties in calibration and discrimination between radon and thoron. From biokinetic and dosimetric model, it has been known that the dominant contribution of thoron to the effective dose is in the lungs. UNSCEAR estimates the doses contribution of thoron and its progenies is between 5-10% of the annual dose received by the general public and the risk level is 4.4 times greater than radon and progenies. Therefore, it is necessary to study the thoron concentration in indoor air and workplaces. Radon-thoron concentration in indoor air can be determined by direct methods using Pylon Model WLx device and passive methods using Solid State Nuclear Track Detector (SSNTDs). In this research the measurement of thoron was carried out continuously using Pylon Model WLx equipment that is sensitive to radon for 24, 65, 72, 116 and 154 hours in different rooms. The measurement result showed that the mean value of thoron working level (WL) concentration obtained in room-1 was 2.53 ± 0.67 Bq/m 3 with maximum and minimum of thoron concentrations were 3.37 and 2.22 Bq/m 3 respectively. From the measurement in different locations, it was obtained that the largest and smallest average concentrations of thoron progenies were 0.83 ± 0.23 Bq/m 3 and 0.29 ± 0.64 Bq/m 3 , while the maximum and minimum concentration values were 7.80 Bq/m 3 and 0.01 Bq/m 3 respectively. Pylon Model WLx device is not enables to be used for longer and large scale survey area concurrently, so the SSNTDs which is sensitive to the emission of alpha particles and can measure cumulative thoron concentrations is required. (author)

  16. Rearing and gamma radiation effects on mature pupae of pink bollworm and their F1 progeny

    International Nuclear Information System (INIS)

    Qureshi, Z.A.; Ahmed, N.; Hussain, T.

    1993-01-01

    Pink bollworm larvae were successfully reared in captivity on a casein wheat germ diet. The substitution of casein with soyflour, corn-cob grit and wheat germ, and casein for peanut flour, resulted in delayed development, reduced pupal recovery and fecundity of the adult moths. This reduction was more drastic in corn-cob grit and peanut flour diets. The irradiation of mature pupae at 50-200 Gy resulted in decreased adult emergence with increased gamma radiation doses, and more deformed moths were recorded at a dose of 200 Gy. Adults following irradiation of mature pupae when crossed with untreated males or females or treated individuals crossed to treated exhibited reduced fecundity and fertility with the increasing doses. This reduction was more pronounced when treated males were crossed with treated females. Females were relatively more sensitive to gamma radiation, as a reduced number of eggs was obtained when treated females were crossed with untreated males. At 200 Gy, no F 1 progeny were obtained from any cross involving treated parents. The fecundity and fertility were reduced significantly when F 1 males or F 1 females from male parents irradiated as mature pupae were mated with untreated insects at both 100 and 150 Gy. However, inherited sterility was more pronounced when F 1 males were crossed with untreated females than when F 1 females were crossed with untreated males. Similarly reduced fecundity and fertility in F 1 progeny from female parents irradiated as mature pupae, both at 100 and 150 Gy, were also recorded in crosses as described for male F 1 progeny. The fecundity and fertility were the lowest in F 1 progeny of both male and female parents irradiated as mature pupae when compared with the F 1 progeny of male or female irradiated parents separately. (author). 28 refs, 7 tabs

  17. Results of the first 5 years of a study on year-to-year variations of radon concentration in Italian dwellings

    International Nuclear Information System (INIS)

    Bochicchio, F.; Ampollini, M.; Antignani, S.; Bruni, B.; Quarto, M.; Venoso, G.

    2009-01-01

    Radon concentration in air is subject to significant variations at different time scales, owing to several factors. In general, the shorter the time period considered, the larger the variations in radon concentration, e.g., day-to-day variations are usually higher than month-to-month variations. An average over 12 consecutive months is generally considered the best estimate of the long-term average radon concentration. Due to practical reasons, however, very few data are available on year-to-year variations. Year-to-year variations can have quite a relevant impact on radon policies and on the assessment of health risks from exposures to radon. Therefore, a project was started in 1996 aimed to evaluate year-to-year variations in a sample of dwellings. Systematic radon measurements have been made with LR 115 based radon detectors (closed type) in the living room and one bedroom of a sample of dwellings in Rome (Italy). The analysis of the results of the first five consecutive years of measurements, regarding the 76 dwellings included in the final analysis, showed relatively low year-to-year variations, with a median coefficient of variation of 14% (range 3%-42%), smaller than that observed in studies from other European countries. Therefore, in the analyzed sample, 12-month measurements can be considered a good estimate of the average radon concentration, at least within a 5-year period. This is quite important for radon regulations and policies, e.g. annual measurements could be recommended and repetition of radon measurements could not be necessary within periods of 5 years. Moreover, the impact of the observed year-to-year variations on the lung cancer risk estimated in the Italian epidemiological study is expected to be not high, if variations on periods up to about 30 years can be assumed similar to those observed in this study.

  18. Inheritance of fruit colour in normal and irradiated progenies of brinjal

    International Nuclear Information System (INIS)

    Gopimony, R.; George, M.K.; Gopinathan Nair, V.

    1980-01-01

    The inheritance of fruit colour in brinjal (Solanum melongena) was studied by analysing the progeny belonging to the F 1 M 2 , F 1 M 1 and F 2 M 2 generations resulting from a cross between varieties insanum and purple giant followed by gamma irradiation. The F 2 phenotypic frequencies fitted very well with the dihybrid ratio indicating that the fruit colour is governed by two independently inherited genes. Three colour mutants, namely, purple, mottled green and white were induced in the F 1 M 1 generation by the irradiation. The appearance of these mutants is explained as due to independent mutations at either or both of the two goenetic loci. The colour pattern in the F 2 M 2 progenies derived from the F 1 M 1 mutants substantiates the two gene mechanism for the inheritance of fruit colour. The genotypes for the different colour types in the F 1 , F 2 and F 1 M 1 mutants have been indicated and discussed. (author)

  19. Distribution of radon concentration in residences and others buildings of Belo Horizonte city, MG, Brazil

    International Nuclear Information System (INIS)

    Santos, Talita de Oliveira

    2010-01-01

    Human beings are exposed to ionizing radiation from many natural sources. Radon and its progeny have been recognized as the most important contributors to the natural radioactivity dose, accounting for about half of all human exposure to ionizing radiation. Radon is a α-radioactive noble gas derived from the natural series of uranium and thorium, which occurs in a wide concentration range in all geological materials, especially, in rocks, soils and waters. By diffusion and convection, radon migrates from the rocks and soils to atmosphere and through fissures, pipes and holes it may enter the dwellings and other buildings. Another important radon source in dwellings is its emanation from the construction material. The radon progeny concentration in dwellings has been receiving considerable global attention due to its potential effect in causing lung cancer if it deposited in upper respiratory tract when inhaled. This work presents radon concentration distribution in dwellings in Metropolitan Region of Belo Horizonte - RMBH. The geological settings of the area are Archean rocks of Granitic Gneissic Complex and of metasediments sequences of the great Precambrian unit of the Iron Quadrangle of Minas Gerais, Brazil. Radon concentration measurements were carried out with continuous detector AlphaGUARD PQ200PRO (Genitron), in passive mode and with passive detectors E-PERM Electrets Ion Chamber-EIC. The radon progeny concentration was carried out with a solid state alpha spectroscope, the DOSEman PRO (Sarad). It was found an indoor radon concentration varying in a large range from 4 to 2664,0 Bq.m"-"3, with an average value of 108.0 Bq.m"-"3, median of 70 Bq.m"-"3, geometric mean equal to 76 Bq.m"-"3 and standard deviation of 170 Bq.m"-"3. About 15% of the results are over the United States Environmental Protection Agency (U.S. EPA) actions level, which is 148 Bq.m"-"3.The equilibrium factor between radon and its progeny were determined in dwellings, as 0.3 in average

  20. Monitoring variation in greenhouse gases concentration in urban environment of Delhi.

    Science.gov (United States)

    Sahay, Samraj; Ghosh, Chirashree

    2013-01-01

    Cities across the globe are considered as major anthropogenic sources of greenhouse gases (GHG), yet very few efforts has been made to monitor ambient concentration of GHG in cities, especially in a developing country like India. Here, variations in the ambient concentrations of carbon dioxide (CO(2)) and methane (CH(4)) in residential, commercial, and industrial areas of Delhi are determined from fortnightly daytime observations from July, 2008 to March, 2009. Results indicate that the average daytime ambient concentration of CO(2) varied from 495 to 554 ppm in authorized residential areas, 503 to 621 ppm in the slums or jhuggies in the unauthorized residential areas, 489 to 582 ppm in commercial areas, and 512 to 568 ppm in industrial areas with an average of 541 ± 27 ppm. CH(4) concentration varied from 652 to 5,356 ppbv in authorized residential areas, 500 to 15,220 ppbv in the unauthorized residential areas, 921 to 11,000 ppbv in the commercial areas, and 250 to 2,550 ppbv in the industrial areas with an average of 3,226 ± 1,090 ppbv. A low mid-afternoon CO(2) concentration was observed at most of the sites, primarily due to strong biospheric photosynthesis coupled with strong vertical mixing.

  1. Spatiotemporal variation of radon and carbon dioxide concentrations in an underground quarry: coupled processes of natural ventilation, barometric pumping and internal mixing.

    Science.gov (United States)

    Perrier, Frédéric; Richon, Patrick

    2010-04-01

    Radon-222 and carbon dioxide concentrations have been measured during several years at several points in the atmosphere of an underground limestone quarry located at a depth of 18 m in Vincennes, near Paris, France. Both concentrations showed a seasonal cycle. Radon concentration varied from 1200 to 2000 Bq m(-3) in summer to about 800-1400 Bq m(-3) in winter, indicating winter ventilation rates varying from 0.6 to 2.5 x 10(-6) s(-1). Carbon dioxide concentration varied from 0.9 to 1.0% in summer, to about 0.1-0.3% in winter. Radon concentration can be corrected for natural ventilation using temperature measurements. The obtained model also accounts for the measured seasonal variation of carbon dioxide. After correction, radon concentrations still exhibit significant temporal variation, mostly associated with the variation of atmospheric pressure, with coupling coefficients varying from -7 to -26 Bq m(-3) hPa(-1). This variation can be accounted for using a barometric pumping model, coupled with natural ventilation in winter, and including internal mixing as well. After correction, radon concentrations exhibit residual temporal variation, poorly correlated between different points, with standard deviations varying from 3 to 6%. This study shows that temporal variation of radon concentrations in underground cavities can be understood to a satisfactory level of detail using non-linear and time-dependent modelling. It is important to understand the temporal variation of radon concentrations and the limitations in their modelling to monitor the properties of natural or artificial underground settings, and to be able to assess the existence of new processes, for example associated with the preparatory phases of volcanic eruptions or earthquakes. Copyright 2009 Elsevier Ltd. All rights reserved.

  2. Identification of steelhead and resident rainbow trout progeny in the Deschutes River, Oregon, revealed with otolith microchemistry

    Science.gov (United States)

    Zimmerman, C.E.; Reeves, G.H.

    2002-01-01

    Comparisons of strontium:calcium (Sr:Ca) ratios in otolith primordia and freshwater growth regions were used to identify the progeny of steelhead Oncorhynchus mykiss (anadromous rainbow trout) and resident rainbow trout in the Deschutes River, Oregon. We cultured progeny of known adult steelhead and resident rainbow trout to confirm the relationship between Sr:Ca ratios in otolith primordia and the life history of the maternal parent. The mean (??SD) Sr:Ca ratio was significantly higher in the otolith primordia of the progeny of steelhead (0.001461 ?? 0.00029; n = 100) than in those of the progeny of resident rainbow trout (0.000829 ?? 0.000012; n = 100). We used comparisons of Sr:Ca ratios in the primordia and first-summer growth regions of otoliths to determine the maternal origin of unknown O. mykiss juveniles (n = 272) collected from rearing habitats within the main-stem Deschutes River and tributary rearing habitats and thus to ascertain the relative proportion of each life history morph in each rearing habitat. Resident rainbow trout fry dominated the bi-monthly samples collected from main-stem rearing habitats between May and November 1995. Steelhead fry dominated samples collected from below waterfalls on two tributaries in 1996 and 1998.

  3. Ray tissues as an indirect measure of relative sap-sugar concentration in sugar maple

    Science.gov (United States)

    Peter W. Garrett; Kenneth R. Dudzik; Kenneth R. Dudzik

    1989-01-01

    Attempts to correlate ray tissue as a percentage of total wood volume with sap-sugar concentrations of sugar maple progenies were unsuccessful. These results raise doubts about our ability to use a relatively constant value such as ray-tissue volume in a selection program designed to increase the sap-sugar concentration of sugar maple seedlings.

  4. Analysis of variation in few-group cross section behavior subjected to burnup and boron concentration

    International Nuclear Information System (INIS)

    Zhang Zongyao; Li Dongsheng.

    1986-01-01

    The paper analyzes the variations of few-group cross section behavior in neutron diffusion subjected to fuel burnup and critical boron concentration in a core. The influences of the behavior on the core excess reactivity, crirical boron concentration, power distribution and the yield of isotopes are also analyzed. A reactor core of samll-medium-sized nuclear power plant is analyzed as an example

  5. Measurement of unattached radon progeny based in electrostatic deposition method; Medicion de la fraccion no unida a aerosoles de la progenie de {sup 222}Rn mediante un metodo de deposicion electrostatica

    Energy Technology Data Exchange (ETDEWEB)

    Canoba, A C; Lopez, F O

    1999-07-01

    A method for the measurement of unattached radon progeny based on its electrostatic deposition onto wire screens, using only one pump, has been implemented and calibrated. The importance of being able of making use of this method is related with the special radiological significance that has the unattached fraction of the short-lived radon progeny. Because of this, the assessment of exposure could be directly related to dose with far greater accuracy than before. The advantages of this method are its simplicity, even with the tools needed for the sample collection, as well as the measurement instruments used. Also, the suitability of this method is enhanced by the fact that it can effectively be used with a simple measuring procedure such as the Kusnetz method. (author)

  6. Seasonal variation of sperm quality and the relationship between spermatocrit and sperm concentration in yamú Brycon amazonicus

    DEFF Research Database (Denmark)

    Cruz-Casallas, Pablo E.; Medina-Robles, Víctor M.; Velasco-Santamaría, Yohana M.

    2007-01-01

    and sperm concentration were examined over two reproductive seasons. Activation time, spermatocrit, and sperm concentration were significantly higher in 2003 than in 2004. Spermatocrit and sperm concentration showed a significant positive relationship (r2=0.79). During the 2004 reproductive season......, a significant variation was observed for spermatocrit and sperm concentration between the initial period (February 15th to March 14th) and the middle and final periods (March 15th to April 14th and April 15th to May 14th, respectively). Neither the ion concentrations nor the glucose and cholesterol...... concentrations varied between any periods of the reproductive season. Osmolality and triglyceride concentrations showed significant variations between periods during the reproductive season....

  7. Radon concentration levels in Fatima Jinnah women university Pakistan

    International Nuclear Information System (INIS)

    Khan, S.A.; Ali, S.; Tufail, A.; Qureshi, A.A.

    2005-01-01

    Public exposure to radioactive gas radon and its progeny present in the air results in the largest contribution to total effective dose received by human beings. It is therefore of great concern to monitor radon concentration in energy conserved air tight buildings. Measurements of radon in the Fatima Jinnah Women University (FJWU) have been carried out for investigation and comparison of radon concentration in the new and old buildings of the campus at Rawalpindi, Pakistan. The study was done because according to the international guidelines concerning environmental problems, it is necessary to evaluate and know the radon levels, especially since most of the natural radiation dose to human beings comes from radon gas and its progeny. Solid State Nuclear Track Detectors (SSNTDs) being efficient, therefore, the measurements were carried out by passive, time integrated method, using CR-39 detector in polythene bags. The detectors were exposed for more than six month in various locations indoors and outdoors. The detectors were etched using NaOH, the tracks were counted manually, and the track density was converted to radon concentration. Radon concentration varied from 31 to 213 Bq.m -3 in old building and from 27 to 143 Bq.m -3 in new buildings, showing slight elevated values in the old buildings. Radon concentration values were found to be less than the values quoted by radiation protection agencies. Radiation dose due to radon varied in the university campus depending on occupancy factor. (author)

  8. Estimation of radon concentration in dwellings in and around ...

    Indian Academy of Sciences (India)

    Besides, it is also known that out of the total radiation dose received from natural and man-made sources, 60% of the dose is due to radon and its progeny. Taking this into account, an attempt has been made to estimate radon concentration in dwellings in and around Guwahati using aluminium dosimeter cups with CR-39 ...

  9. Effects of oral, subchronic cadmium administration on fertility prenatal and postnatal progeny development in rats

    Energy Technology Data Exchange (ETDEWEB)

    Baranski, B.; Stetkiewicz, I.; Sitarek, K.; Szymczak, W.

    1983-12-01

    Cadmium chloride was administered by gavage to female rats 5 days a week for 5 weeks, then during mating and gestation periods at doses of 0.04, 0.4, and 4 mg Cd/kg/day. Treatment with cadmium neither affected the survival and fertility of females, nor produced overt fetotoxic effects. Fetal cadmium concentration was not related to the level of exposure. Litter size, body weight gain and viability of offspring during 2 months after parturition were similar in all groups. The exploratory locomotor activity of 2-month-old males and females born to rats given 0.4 and 4 mg Cd/kg/day was significantly reduced. The progeny of cadmium-treated females showed decreased performance in the rotarod test. In general, the degree of behavioral impairment was dose-related.

  10. Atmospheric concentration of 210Pb in East Asia and its contribution to Japanese islands by long-range transport

    International Nuclear Information System (INIS)

    Doi, Taeko; Sato, Shin; Sato, Jun

    2007-01-01

    Atmospheric 210 Pb is a long-lived progeny of 222 Rn generated from the earth's crust and exists as adsorbed onto the surface of aerosol particles. The distribution of atmospheric 210 Pb in East Asia reflects (1) the concentration levels in continental and maritime air masses and (2) the spatial extent of the continental air mass. This paper reviews the previously observed results on seasonal variation of 210 Pb concentration at several sites of Japan, Korea and China to evaluate the contribution of continental to Japanese atmosphere, and the specific activity of 210 Pb in the main components of aerosol samples and discusses from the view point of the Japanese islands. The authors conclude that aerosols from continental East Asia in winter contain more soil particles with low specific radioactivity of 210 Pb than the aerosols in Japan and that the natural radionuclide is extremely useful tracer for researches on meteorological phenomena and global transfer of environmental pollution. (S. Ohno)

  11. Selección por conformación de reproductores de tilapia roja Oreochromis sp., mediante prueba de progenie

    Directory of Open Access Journals (Sweden)

    Hermes Pineda S.

    2013-10-01

    Full Text Available Objetivo. Contribuir con la caracterización estadística y genotípica (media, media del error estándar, varianza y heredabilidad de la Longitud Total (LT y Longitud Altura del Lomo (LAL, y plantear una estrategia de selección para mejorar la calidad de la semilla de reproductores de tilapia roja Oreochromis sp. Materiales y métodos. El proyecto se realizó en la Granja Experimental y de Producción Piscícola (PCJIC, a un Km del municipio de San Jerónimo, distante 61 Km al Occidente de Medellín (Antioquia. Se conformaron tres grupos de cruzamientos, cada uno en proporción de 3 hembras por 1 macho así: un cruce Hembras Blancas (HB x Macho Rojo (MR y dos cruces Hembras Blancas (HB x Macho Blanco (MB. Las progenies fueron medidas a los 60 días post eclosión, teniendo en cuenta los supuestos estadísticos. Resultados. El ANOVA mostró que las progenies difieren significativamente (p<0.001 para ambas variables continuas. La LT fue mayor para la progenie del cruzamiento HBxMB sin reversión (8.04±1.04cm y LAL fue mayor para la progenie HBxMR (2.33±0.44cm. La correlación pareada entre las variables fue altamente significativa (r≥0.79, p<0.001. Las heredabilidades fueron 0.59 (LT y 0.64 (LAL. Los porcentajes de manchas en las progenies fueron HBxMR (34% y HBxMB no revertida (66%. Conclusiones. La progenie del Grupo 1 HBxMR tuvo los reproductores para una mejor selección por conformación, por lo que se sugiere aumentar el número de animales con mayor LAL. También, considerar la menor cantidad de manchas oscuras y realizar un manejo de reproductores por grupos independientes para selección masal.

  12. Study on the variation of the distant crossing rice by ion beam implantation

    International Nuclear Information System (INIS)

    Wu Yuejin; Li Hong; Song Mei; Yu Zengliang; Wu Jingde; Tong Jiping; Zheng Leya

    2005-01-01

    The following contents including the original receptor EI213 and other two control materials, RAPD polymorphism, photosynthetic efficiency, and the number of vascular bundles of the first internodes below the peduncle have been studied for the eight F7 transgenic lines obtained from ion beam implantation. The results showed that there was a significant variation in genomes of maize-rice line, compared with the receptor EI213, after the total exogenous maize DNA was introduced into EI213. The number of the vascular bundles of maize-rich progeny's line was obviously much larger than those of the original receptor EI213 and other two controls GER-3 and MH63, and along with the photosynthetic efficiency of maize-rice progeny's lines being gone up. Moreover, the parenchyma cells around the vascular bundles of the transgenic lines became much larger in number and in size than those around the controls. All these indicated that the maize-rich progeny's lines are really different from and superior to the receptor and the controls. It is a novel and useful way to apply ion beam implantation in transferring DNA from C 4 plant maize into C 3 plant rice. (authors)

  13. Temporal variations of radon concentration in the saturated soil of Alpine grassland: The role of groundwater flow

    International Nuclear Information System (INIS)

    Perrier, Frederic; Richon, Patrick; Sabroux, Jean-Christophe

    2009-01-01

    Radon concentration has been monitored from 1995 to 1999 in the soil of the Sur-Fretes ridge (French Alps), covered with snow from November to April. Measurements were performed at 70 cm depth, with a sampling time of 1 h, at two points: the summit of the ridge, at an altitude of 1792 m, and the bottom of the ridge, at an altitude of 1590 m. On the summit, radon concentration shows a moderate seasonal variation, with a high value from October to April (winter), and a low value from May to September (summer). At the bottom of the ridge, a large and opposite seasonal variation is observed, with a low value in winter and a high value in summer. Fluctuations of the radon concentration seem to be associated with temperature variations, an effect which is largely delusory. Indeed, these variations are actually due to water infiltration. A simplified mixing model is used to show that, at the summit of the ridge, two effects compete in the radon response: a slow infiltration response, rich in radon, with a typical time scale of days, and a fast infiltration of radon-poor rainwater. At the bottom of the ridge, similarly, two groundwater contributions compete: one slow infiltration response, similar to the response seen at the summit, and an additional slower response, with a typical time scale of about a month. This second slower response can be interpreted as the aquifer discharge in response to snow melt. This study shows that, while caution is necessary to properly interpret the various effects, the temporal variations of the radon concentration in soil can be understood reasonably well, and appear to be a sensitive tool to study the subtle interplay of near surface transfer processes of groundwater with different transit times

  14. Temporal variations of radon concentration in the saturated soil of Alpine grassland: the role of groundwater flow.

    Science.gov (United States)

    Perrier, Frédéric; Richon, Patrick; Sabroux, Jean-Christophe

    2009-03-15

    Radon concentration has been monitored from 1995 to 1999 in the soil of the Sur-Frêtes ridge (French Alps), covered with snow from November to April. Measurements were performed at 70 cm depth, with a sampling time of 1 h, at two points: the summit of the ridge, at an altitude of 1792 m, and the bottom of the ridge, at an altitude of 1590 m. On the summit, radon concentration shows a moderate seasonal variation, with a high value from October to April (winter), and a low value from May to September (summer). At the bottom of the ridge, a large and opposite seasonal variation is observed, with a low value in winter and a high value in summer. Fluctuations of the radon concentration seem to be associated with temperature variations, an effect which is largely delusory. Indeed, these variations are actually due to water infiltration. A simplified mixing model is used to show that, at the summit of the ridge, two effects compete in the radon response: a slow infiltration response, rich in radon, with a typical time scale of days, and a fast infiltration of radon-poor rainwater. At the bottom of the ridge, similarly, two groundwater contributions compete: one slow infiltration response, similar to the response seen at the summit, and an additional slower response, with a typical time scale of about a month. This second slower response can be interpreted as the aquifer discharge in response to snow melt. This study shows that, while caution is necessary to properly interpret the various effects, the temporal variations of the radon concentration in soil can be understood reasonably well, and appear to be a sensitive tool to study the subtle interplay of near surface transfer processes of groundwater with different transit times.

  15. The influence of variation of deuterium's concentration on the immunity system

    International Nuclear Information System (INIS)

    Tamaian, Radu

    2007-01-01

    Hydrogen's substitution by deuterium represents an environmental alteration at which the organism (in vivo) and the cells (in vitro), respectively, if they can't accommodate will recede. In this way the variations of deuterium's isotopic abundance can be compared with the environmental factors of stress (variations of temperature, quantity of nourishment, radiations, etc). As different forms of existence of life are more or less sensitive at environment's factors variations, so they respond in different ways to concentration variations of deuterium from the living environment/organism. Consequently the mammals' immunity system (IS) presents different feed-backs. The main results are stressed as follows: - a. The use as alimentary adjuvant of deuterium depleted water (DDW) in prolonged periods (21 days) increased the capacity of unspecific immunity defense against the specific bacterial aggression, both in Gram-positive bacteria (Streptococcus pneumoniae558) and of Gram-negative (Klebsiella pneumoniae507); - b. The immunosuppression determined by cyclophosphamide-alquilant agent with medullary depletion of white series reduced the survival of inoculated animals, even in the conditions in which the animals have received dietary supplement with DDW; - c. The immunosuppression through medullary depletion due to irradiation reduced also the survival of inoculated animals, even in the conditions in which the animals have received dietary supplement with DDW. Those mentioned herein lead to the hypothesis that prolonged administration of DDW simulates the unspecific immunity defence, probably through the stimulation of the hematogenic marrow and of lymphopoietic and granulopoietic stem cells. (author)

  16. Sudetic larch in Germany - Results of provenance and progeny research

    Energy Technology Data Exchange (ETDEWEB)

    Weisgerber, H. [Forest Centre for Management Planning, Research and Ecology, Hann Muenden (Germany)

    1995-12-31

    There are only a few older sources of Sudetic larch in Germany. They distinguish themselves by outstanding growth and low susceptibility to canker. This impression was confirmed by results of provenance research. The Sudetic larch tested in comparison with numerous other provenances proved to be fast-growing, site-tolerant, to a large extent insusceptible to canker, with straight but also slightly to moderately curved stems. The Sudetic provenances behave remarkably uniformly as regards these characteristics. In addition to provenance research investigations have been going on for a long time in Germany into individual differences within the Sudetic larch populations. A report is given on the results of progeny tests from free and controlled pollination, using the example of a seed orchard consisting of 54 clones. We point also to possibilities for improving stem quality by selection steps. The results of provenance and progeny research on Sudetic larch are in the meantime being put to use to a large extent in practical forestry. The forest administrations of various federal lands recommend the use of reproductive material of Sudetic origin and from seed orchards. 20 refs, 3 figs

  17. Sudetic larch in Germany - Results of provenance and progeny research

    Energy Technology Data Exchange (ETDEWEB)

    Weisgerber, H [Forest Centre for Management Planning, Research and Ecology, Hann Muenden (Germany)

    1996-12-31

    There are only a few older sources of Sudetic larch in Germany. They distinguish themselves by outstanding growth and low susceptibility to canker. This impression was confirmed by results of provenance research. The Sudetic larch tested in comparison with numerous other provenances proved to be fast-growing, site-tolerant, to a large extent insusceptible to canker, with straight but also slightly to moderately curved stems. The Sudetic provenances behave remarkably uniformly as regards these characteristics. In addition to provenance research investigations have been going on for a long time in Germany into individual differences within the Sudetic larch populations. A report is given on the results of progeny tests from free and controlled pollination, using the example of a seed orchard consisting of 54 clones. We point also to possibilities for improving stem quality by selection steps. The results of provenance and progeny research on Sudetic larch are in the meantime being put to use to a large extent in practical forestry. The forest administrations of various federal lands recommend the use of reproductive material of Sudetic origin and from seed orchards. 20 refs, 3 figs

  18. Epstein-Barr Virus BKRF4 Gene Product Is Required for Efficient Progeny Production.

    Science.gov (United States)

    Masud, H M Abdullah Al; Watanabe, Takahiro; Yoshida, Masahiro; Sato, Yoshitaka; Goshima, Fumi; Kimura, Hiroshi; Murata, Takayuki

    2017-12-01

    Epstein-Barr virus (EBV), a member of human gammaherpesvirus, infects mainly B cells. EBV has two alternative life cycles, latent and lytic, and is reactivated occasionally from the latent stage to the lytic cycle. To combat EBV-associated disorders, understanding the molecular mechanisms of the EBV lytic replication cycle is also important. Here, we focused on an EBV lytic gene, BKRF4. Using our anti-BKRF4 antibody, we revealed that the BKRF4 gene product is expressed during the lytic cycle with late kinetics. To characterize the role of BKRF4, we constructed BKRF4-knockout mutants using the bacterial artificial chromosome (BAC) and CRISPR/Cas9 systems. Although disruption of the BKRF4 gene had almost no effect on viral protein expression and DNA synthesis, it significantly decreased progeny virion levels in HEK293 and Akata cells. Furthermore, we show that BKRF4 is involved not only in production of progeny virions but also in increasing the infectivity of the virus particles. Immunoprecipitation assays revealed that BKRF4 interacted with a virion protein, BGLF2. We showed that the C-terminal region of BKRF4 was critical for this interaction and for efficient progeny production. Immunofluorescence analysis revealed that BKRF4 partially colocalized with BGLF2 in the nucleus and perinuclear region. Finally, we showed that BKRF4 is a phosphorylated, possible tegument protein and that the EBV protein kinase BGLF4 may be important for this phosphorylation. Taken together, our data suggest that BKRF4 is involved in the production of infectious virions. IMPORTANCE Although the latent genes of EBV have been studied extensively, the lytic genes are less well characterized. This study focused on one such lytic gene, BKRF4, which is conserved only among gammaherpesviruses (ORF45 of Kaposi's sarcoma-associated herpesvirus or murine herpesvirus 68). After preparing the BKRF4 knockout virus using B95-8 EBV-BAC, we demonstrated that the BKRF4 gene was involved in infectious

  19. Contribution of progenies segregating for macromutations to the micromutations in lentil (Lens culinaris Medik.)

    International Nuclear Information System (INIS)

    Solanki, I.S.; Sharma, B.

    2001-01-01

    Healthy seeds of a macrosperma lentil cv Precoz Selection were treated with three doses each of ethylene imine (EI), N-nitroso-N-ethyl urea (NEU) and gamma rays. The M1 material in each treatment was classified into four groups of mutagenic damage. On the basis of macromutations induced in M2 generation, different progenies were classified into two broad groups, i.e. macromutational and non-macromutational. The latter group was again classified into selected and unselected groups on the basis of inter- and intra-family selection in M2. M3 consisted of three distinct plant populations, viz., macromutational, selected and unselected. With regard to CV, different M3 populations were observed in the order: macromutational unselected selected. NEU induced the highest amount of polygenic variability for different characters in various populations, followed by EI and gamma rays. The highest frequency of promising progenies was obtained in the selected population, followed by macromutational and unselected populations. The contribution of selected population to the total M3 promising progenies was the highest, followed by unselected and macromutational populations. Among mutagens, NEU and, between damage groups, HH (high seedling damage and high sterility) contributed maximum to total M3 promising selections [it

  20. SSR marker analysis on genetic variation of M3 from maize inbred lines 48-2 and R08 after irradiation inducement

    International Nuclear Information System (INIS)

    Li Qi; Shi Haichun; Ke Yongpei; Yuan Jichao; Yu Xuejie

    2011-01-01

    Analyzing the biological effects and the genetic variations of maize mutagenic progenies is important to facilitate effective selections and utilization of the mutants. In this study, the genetic variation of 103 mutagenic progenies of M 3 lines of inbred lines 48-2 and R08 with 60 Co γ-rays inducement were evaluated with SSR molecular markers. The results indicated that, the amplitude of polymorphism information content (PIC) of the 48-2 and R08 M 3 lines ranged 0.307 ∼ 0.948 and 0.108 ∼ 0.955, with an average of 0.762 and 0.701, respectively. The amplitude of genetic diversity indexes (H') ranged 0.552 ∼ 2.830 and 0.254 ∼ 3.309, with an average of 1.830 and 1.777, respectively. The average value of genetic similarity coefficient of the 49 M 3 lines of 48-2 with its check (M673) was 0.8194. However, the average value of genetic similarity coefficient of the M 3 lines of R08 with its check (M487) was 0.8373. Based on the genetic similarity coefficient, inbred lines 48-2, R08 and their 101 M 3 lines were clustered in 7 and 5 populations respectively. This phenomenon indicated that massive genetic variation could appear in progenies due to irradiation. The strengthen of selection and utilization of mutants based on the breeding objectives and in accordance with the feature and regularity on genetic variations of main characteristics of mutant lines in various populations could be enhanced in breeding program, to some extent, which can increase the breeding efficiency of irradiation induced mutation in maize. (authors)

  1. Diurnal variation and reliability of the urine lactate concentration after maximal exercise.

    Science.gov (United States)

    Nikolaidis, Stefanos; Kosmidis, Ioannis; Sougioultzis, Michail; Kabasakalis, Athanasios; Mougios, Vassilis

    2018-01-01

    The postexercise urine lactate concentration is a novel valid exercise biomarker, which has exhibited satisfactory reliability in the morning hours under controlled water intake. The aim of the present study was to investigate the diurnal variation of the postexercise urine lactate concentration and its reliability in the afternoon hours. Thirty-two healthy children (11 boys and 21 girls) and 23 adults (13 men and 10 women) participated in the study. All participants performed two identical sessions of eight 25 m bouts of maximal freestyle swimming executed every 2 min with passive recovery in between. These sessions were performed in the morning and afternoon and were separated by 3-4 days. Adults performed an additional afternoon session that was also separated by 3-4 days. All swimmers drank 500 mL of water before and another 500 mL after each test. Capillary blood and urine samples were collected before and after each test for lactate determination. Urine creatinine, urine density and body water content were also measured. The intraclass correlation coefficient was used as a reliability index between the morning and afternoon tests, as well as between the afternoon test and retest. Swimming performance and body water content exhibited excellent reliability in both children and adults. The postexercise blood lactate concentration did not show diurnal variation, showing a good reliability between the morning and afternoon tests, as well as high reliability between the afternoon test and retest. The postexercise urine density and lactate concentration were affected by time of day. However, when lactate was normalized to creatinine, it exhibited excellent reliability in children and good-to-high reliability in adults. The postexercise urine lactate concentration showed high reliability between the afternoon test and retest, independent of creatinine normalization. The postexercise blood and urine lactate concentrations were significantly correlated in all

  2. Selection and genetic gains for juvenile traits in progenies of Hevea in São Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    Paulo de Souza Gonçalves

    2004-01-01

    Full Text Available Five yield traits were investigated in three-year-old progenies from open-pollinated rubber trees [Hevea brasiliensis (Willd. ex Adr. de Juss Muell.-Arg.]. Twenty progenies were evaluated in a randomized, complete block design replicated three times using 10 plants per linear plot at the North Central Experimental Station in Pindorama, São Paulo State, Brazil. The characters evaluated included the average yield of rubber, growth vigor, bark thickness, total number of latex vessel rings and latex vessel size. Highly significant (p were 37%, 35%, 69%, 10% and 16%, respectively. Significant positive genotypic and phenotypic correlations were found between the yield of rubber and growth vigor (r g = 0.73, r p = 0.70, bark thickness (r g = 0.70**, r p = 0.75** and the total number of latex vessel rings (r g = 0.64, r p = 0.80. There was no relationship between yield and latex vessel size, growth vigor or total number of latex vessel rings. Based on these data, selecting the best two out of 20 progenies would result in a genetic gain of 12.3% and 6.8% for yield of rubber and growth vigor, respectively. The two best individual ortets within each progeny would result in a genetic gain of 27.7% and 9.1%, with a total gain of 40% and 16% for these two traits, respectively.

  3. Temporal variations of methane concentration and isotopic composition in groundwater of the St. Lawrence Lowlands, eastern Canada

    Science.gov (United States)

    Rivard, Christine; Bordeleau, Geneviève; Lavoie, Denis; Lefebvre, René; Malet, Xavier

    2018-03-01

    Dissolved methane concentrations in shallow groundwater are known to vary both spatially and temporally. The extent of these variations is poorly documented although this knowledge is critical for distinguishing natural fluctuations from anthropogenic impacts stemming from oil and gas activities. This issue was addressed as part of a groundwater research project aiming to assess the risk of shale gas development for groundwater quality over a 500-km2 area in the St. Lawrence Lowlands (Quebec, Canada). A specific study was carried out to define the natural variability of methane concentrations and carbon and hydrogen isotope ratios in groundwater, as dissolved methane is naturally ubiquitous in aquifers of this area. Monitoring was carried out over a period of up to 2.5 years in seven monitoring wells. Results showed that for a given well, using the same sampling depth and technique, methane concentrations can vary over time from 2.5 to 6 times relative to the lowest recorded value. Methane isotopic composition, which is a useful tool to distinguish gas origin, was found to be stable for most wells, but varied significantly over time in the two wells where methane concentrations are the lowest. The use of concentration ratios, as well as isotopic composition of methane and dissolved inorganic carbon (DIC), helped unravel the processes responsible for these variations. This study indicates that both methane concentrations and isotopic composition, as well as DIC isotopes, should be regularly monitored over at least 1 year to establish their potential natural variations prior to hydrocarbon development.

  4. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.

    1992-07-01

    This report describes studies on the chemical and physical behavior of the [sup 218]Po atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity in the sub-10 nm size range result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and its dose to the cells in the respiratory tract are to be fully assessed. The specific tasks of the controlled laboratory studies are to determine the formation rates of [center dot]OH radicals formed by the radiolysis of air following radon decay, to examine the formation of particles by the radiolytic oxidation of substances like SO[sub 2] ethylene, and H[sub 2]S to lower vapor pressure compounds and determine the role of gas phase additives such as H[sub 2]O and NH[sub 3] in determining the particle size, to measure the rate of ion-induced nucleation using a thermal diffusion cloud chamber, and to measure the neutralization rate of [sup 218]Po[sub x][sup +] in O[sub 2] at low radon concentrations. Tasks of the exposure studies in occupied indoor spaces are to initiate measurements of the activity size distributions in actual homes with occupants present so that the variability of the indoor activity size distributions can be assessed with respect to indoor aerosol sources and general lifestyle variations of the occupants, to initiate a prospective study of the utility of measurement of deposited [sup 210]Pb embedded in glass surfaces as a measure of the long-term, integrated exposure of the population to radon, and to develop the methodology to determine the hygroscopicity of the indoor aerosol so that the changes in deposition efficiency of the radioactive indoor aerosol with hygroscopic growth in the respiratory tract can be assessed.

  5. Circadian variation in serum cortisol during hydrocortisone replacement is not attributable to changes in cortisol-binding globulin concentrations.

    Science.gov (United States)

    Chung, T T; Gunganah, K; Monson, J P; Drake, W M

    2016-04-01

    Patients taking hydrocortisone (HC) replacement for primary or secondary adrenal failure require individual adjustment of their dose. In addition to modifying the administered doses of HC for each patient, physicians are increasingly interested in variations in the bioavailability of glucocorticoid replacement. One potential determinant of the bioavailability of replaced HC is a variation in serum cortisol-binding globulin (CBG) concentration, which may, in turn, affect interpretation of cortisol profiles and individual dose selection for patients on hydrocortisone replacement therapy. To investigate the hypothesis that there is a circadian variation in CBG levels. A total of 34 male patients divided into 3 groups (10 patients with non-somatotroph structural pituitary disease on HC replacement, 11 patients with treated acromegaly on HC replacement and 13 patients with treated acromegaly not on HC replacement) and 10 healthy volunteers were included. Cortisol and CBG levels were measured at 6 time points (0800, 1100, 1300, 1500, 1700 and 1900). No significant circadian variation in CBG concentration was found in any of the 4 groups. Circadian variation in serum cortisol during hydrocortisone replacement is not attributable to changes in cortisol-binding globulin concentration. Changes in serum cortisol levels may thus be explained by other factors including 11 β-hydroxysteroid dehydrogenase type 1 activity or circadian changes in the binding properties of CBG. © 2015 John Wiley & Sons Ltd.

  6. Eco-logo-genetical characteristic of seed progeny of the Taraxacum officinale S.L. from the zone of east-ural radioactive trace

    International Nuclear Information System (INIS)

    Pozolotina, V.; Ulyanova, E.

    2004-01-01

    Levels of soil contamination with 90 Sr and 137 Cs radionuclides within the zone of Eastern-Ural radioactive trace, at the plots differently distant from the place of Kyshtym accident of 1957, exceed values of the global level 4-40 times. It was shown that the same coeno-population from EURT in the different years revealed the whole variety of previously described low-level irradiation effects. They are: stimulating one (vitality indexes in seed progeny exceed significantly those registered in the background samples); the depressing one, marked for high mortality level; and an indifferent effect showing neither significant differences from the background plants. Variation scope exceeding the normal one in regard to plants growth and development rates, as well as high frequencies of chromosome and morphological aberrations indicate to the plant genome non-stability caused by chronic low-level irradiation loads. Seed progeny also demonstrated the similar ambiguous response to additional irradiation, which is confirmed by allozyme analysis results. Standard electrophoretic methods are applicable to the dandelion studies. Some enzyme systems (Got, Dia) seem to be more suitable for seedlings, whereas the others provided satisfactory results being used for the seed material. In plant coeno-populations situated in radionuclides-polluted zone, genomic recombination processes show higher intensity. High enzymatic variability provides the material for natural selection and increase the adaptive potential of coeno-populations. (author)

  7. A review of lung-to-blood absorption rates for radon progeny

    International Nuclear Information System (INIS)

    Marsh, J. W.; Bailey, M. R.

    2013-01-01

    The International Commission on Radiological Protection (ICRP) Publication 66 Human Respiratory Tract Model (HRTM) treats clearance of materials from the respiratory tract as a competitive process between absorption into blood and particle transport to the alimentary tract and lymphatics. The ICRP recommended default absorption rates for lead and polonium (Type M) in ICRP Publication 71 but stated that the values were not appropriate for short-lived radon progeny. This paper reviews and evaluates published data from volunteer and laboratory animal experiments to estimate the HRTM absorption parameter values for short-lived radon progeny. Animal studies showed that lead ions have two phases of absorption: ∼10 % absorbed with a half-time of ∼15 min, the rest with a half-time of ∼10 h. The studies also indicated that some of the lead ions were bound to respiratory tract components. Bound fractions, f b , for lead were estimated from volunteer and animal studies and ranged from 0.2 to 0.8. Based on the evaluations of published data, the following HRTM absorption parameter values were derived for lead as a decay product of radon: f r = 0.1, s r = 100 d -1 , s s = 1.7 d -1 , f b = 0.5 and s b = 1.7 d -1 . Effective doses calculated assuming these absorption parameter values instead of a single absorption half-time of 10 h with no binding (as has generally been assumed) are only a few per cent higher. However, as there is some conflicting evidence on the absorption kinetics for radon progeny, dose calculations have been carried out for different sets of absorption parameter values derived from different studies. The results of these calculations are discussed. (authors)

  8. Cow and herd variation in milk urea nitrogen concentrations in lactating dairy cattle.

    Science.gov (United States)

    Aguilar, M; Hanigan, M D; Tucker, H A; Jones, B L; Garbade, S K; McGilliard, M L; Stallings, C C; Knowlton, K F; James, R E

    2012-12-01

    Milk urea nitrogen (MUN) is correlated with N balance, N intake, and dietary N content, and thus is a good indicator of proper feeding management with respect to protein. It is commonly used to monitor feeding programs to achieve environmental goals; however, genetic diversity also exists among cows. It was hypothesized that phenotypic diversity among cows could bias feed management decisions when monitoring tools do not consider genetic diversity associated with MUN. The objective of the work was to evaluate the effect of cow and herd variation on MUN. Data from 2 previously published research trials and a field trial were subjected to multivariate regression analyses using a mixed model. Analyses of the research trial data showed that MUN concentrations could be predicted equally well from diet composition, milk yield, and milk components regardless of whether dry matter intake was included in the regression model. This indicated that cow and herd variation could be accurately estimated from field trial data when feed intake was not known. Milk urea N was correlated with dietary protein and neutral detergent fiber content, milk yield, milk protein content, and days in milk for both data sets. Cow was a highly significant determinant of MUN regardless of the data set used, and herd trended to significance for the field trial data. When all other variables were held constant, a percentage unit change in dietary protein concentration resulted in a 1.1mg/dL change in MUN. Least squares means estimates of MUN concentrations across herds ranged from a low of 13.6 mg/dL to a high of 17.3 mg/dL. If the observed MUN for the high herd were caused solely by high crude protein feeding, then the herd would have to reduce dietary protein to a concentration of 12.8% of dry matter to achieve a MUN concentration of 12 mg/dL, likely resulting in lost milk production. If the observed phenotypic variation is due to genetic differences among cows, genetic choices could result in

  9. Toxicity of some insecticides to F1 progeny of the cotton leaf worm; Spodoptera littoralis (Boisd) gamma irradiated as parental pupae (Lepidoptera: Noctuidae)

    International Nuclear Information System (INIS)

    El-Shall, S.S.A.; Hazaa, M.A.M.; Alm El-Din, M.M.S.

    2006-01-01

    The response of the F1 Progeny of Cotton Leaf worm; Spodoptera littoralis Boisd, (from male irradiated as parental pupae with 0, 50, 100 and 150 Gy of gamma irradiation) to Silicron, Atabron and Catabroun were studied. The lethal concentration doses of insecticides that kill 10,50 and 90 % of population (LC 10 , LC 50 and LC 90 ); The lethal time that kill 50% of population (LT 50 ) and the Tolerance Ratio(T.R) to the different previous insecticides were employed as parameters for measuring the response of irradiated and un-irradiated progeny. The results indicated that, the dose of irradiation and time post insecticides application had a great role in alter the response of F1 progeny of S. littoralis to the different-insecticides. Also, gamma irradiation increased the toxicity of Silicron at 2 and 4 days post insecticide treatments. By time elapsing after insecticide application the irradiated larvae became virtually the same degree of susceptibility as compared to non-irradiated ones. As well, 50 Gy slightly alter the toxicity of Atabron, while population irradiated with 100 and 150 Gy showed a high level of susceptibility to Atabron at 22 and 26 days post insecticide treatments as compared to un-irradiated population. In addition, the toxicity of Catabroun increased in case of irradiated population at most of interval time post insecticide treatments as compared to un-irradiated ones. Furthermore, a Comparison was made and discussed between the susceptibility of irradiated population only, population treated with insecticides only and population treated with both insecticides and radiation by using the standard parameter LT 50

  10. Seedling-sapling growth variation in a southern Illinios black walnut provenance/progeny test

    Science.gov (United States)

    George Rink; J. W. Van Sambeek

    1987-01-01

    Nursery root and shoot measurements and annual height, basal diameter and survival data for the 5 years after outplanting were used to describe black walnut growth variation in southern Illinois. At age 5 sapling height narrow-sense heritability was found to be 0.49 for 131 open-pollinated families from across the black walnut comercial range. Greatest height and...

  11. Study on the influence of CR-39 detector size on radon progeny detection in indoor environments

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, L. A.; Hadler, J. C.; Lixandrão F, A. L.; Guedes, S.; Takizawa, R. H. [Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, UNICAMP, 13083-970 Campinas, SP (Brazil)

    2014-11-11

    It is well known that radon daughters up to {sup 214}Po are the real contaminants to be considered in case of indoor radon contamination. Assemblies consisting of 6 circular bare sheets of CR-39, a nuclear track detector, with radius varying from 0.15 to 1.2 cm were exposed far from any material surface for periods of approximately 6 months in 13 different indoor rooms (7 workplaces and 6 dwellings), where ventilation was moderate or poor. It was observed that track density was as greater as smaller was the detector radius. Track density data were fitted using an equation deduced based on the assumption that the behavior of radon and its progeny in the air was described by Fick's Law, i.e., when the main mechanism of transport of radon progeny in the air is diffusion. As many people spend great part of their time in closed or poorly ventilated environments, the confirmation they present equilibrium between radon and its progeny is an interesting start for dosimetric calculations concerning this contamination.

  12. Radon and progeny sourced dose assessment of spa employees in balneological sites

    International Nuclear Information System (INIS)

    Kemal Uzun, Sefa; Demiroez, Isik

    2016-01-01

    This study was conducted in the scope of IAEA project with the name 'Establishing a Systematic Radioactivity Survey and Total Effective Dose Assessment in Natural Balneological Sites' (TUR/9/018), at the Health Physics department of Saraykoey Nuclear Research and Training Center (SANAEM). The aim of this study is estimation of radon and progeny sourced effective dose for the people who are working at the spa facilities by measuring radon activity concentration (RAC) at the ambient air of indoor spa pools and dressing rooms. As it is known, the source of the radon gas is the radium content of the earth crust. Therefore, thermal waters coming from ground may contain dissolved radon and the radon can diffuse water to air. So the ambient air of spa pools can contain serious RAC that depends on a lot of parameters. In this regard, RAC measurements were executed at the 70 spa facilities in Turkey. The measurements were done with both active and passive methods at ambient air of spa pools and dressing rooms. Thus, active measurements were carried out by using the Alphaguard R with diffusion mode during half an hour, and passive measurements were carried out by using the humidity resistive CR-39 radon detectors during 2 months. Results show that RAC values at ambient air of spa pools varies between 13 Bq m -3 and 10 kBq m -3 . Because long-term measurements are more reliable, if it is available, for dose calculations passive radon measurements (with CR-39 detectors) at ambient air of spa pools and dressing rooms were used, otherwise active measurement results were used. With the measurement by the conversion coefficients of ICRP 65 and occupational data of the employees has got from questionnaire forms, effective dose values were calculated. According to the calculations, spa employees are exposed to annual average dose between 0.05 and 29 mSv because of radon and progeny. (authors)

  13. No significant level of inheritable interchromosomal aberrations in the progeny of bystander primary human fibroblasts after alpha particle irradiation

    Science.gov (United States)

    Hu, Burong; Zhu, Jiayun; Zhou, Hongning; Hei, Tom K.

    2013-02-01

    A major concern for bystander effects is the probability that normal healthy cells adjacent to the irradiated cells become genomically unstable and undergo further carcinogenesis after therapeutic irradiation or space mission where astronauts are exposed to low dose of heavy ions. Genomic instability is a hallmark of cancer cells. In the present study, two irradiation protocols were performed in order to ensure pure populations of bystander cells and the genomic instability in their progeny were investigated. After irradiation, chromosomal aberrations of cells were analyzed at designated time points using G2 phase premature chromosome condensation (G2-PCC) coupled with Giemsa staining and with multiplex fluorescent in situ hybridization (mFISH). Our Giemsa staining assay demonstrated that elevated yields of chromatid breaks were induced in the progeny of pure bystander primary fibroblasts up to 20 days after irradiation. mFISH assay showed no significant level of inheritable interchromosomal aberrations were induced in the progeny of the bystander cell groups, while the fractions of gross aberrations (chromatid breaks or chromosomal breaks) significantly increased in some bystander cell groups. These results suggest that genomic instability occurred in the progeny of the irradiation associated bystander normal fibroblasts exclude the inheritable interchromosomal aberration.

  14. Study on character variation induced by introducing exogenous DNA into upland cotton with ion implantation

    International Nuclear Information System (INIS)

    Cheng Beijiu; Tian Qiuyuan; Li Zhan; Zhou Liren

    1996-01-01

    The exogenous DNAs of G. Bickll P. and H. Cannabinus were introduced into the upland cotton Si 2 by Ar + implantation and DNA solution trickling method. The results showed that the exogenous DNA introduction was promoted significantly and the types and frequencies of character variation in progeny were increased by Ar + implantation. Furthermore, most of the variation tend to be stable. Among the Ar + implantation doses tested, 2 x 10 15 Ar + /cm 2 was the best for introducing exogenous DNA and inducing character variation, the variation rate reached to 16.2%. Some new lines with character of resistance to wilt disease, early maturity, few gland in seed and fine fiber quality have been obtained

  15. Epigenetic, histopathological and transcriptomic effects following exposure to depleted uranium in adult zebrafish and their progeny

    Energy Technology Data Exchange (ETDEWEB)

    Gombeau, Kewin, E-mail: kewin.gombeau@gmail.com [Institut de Radioprotection et de SÛreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Bourdineaud, Jean-Paul, E-mail: jean-paul.bourdineaud@u-bordeaux.fr [Université de Bordeaux, CNRS, UMR 5805, EPOC, 33400 Talence (France); Ravanat, Jean-Luc, E-mail: jean-luc.ravanat@cea.fr [Univ. Grenoble Alpes, INAC-SyMMES, 38000 Grenoble (France); CEA, INAC-SCIB Laboratoire des Lésions des Acides Nucléiques, 38000 Grenoble (France); Armant, Olivier, E-mail: olivier.armant@irsn.fr [Institut de Radioprotection et de SÛreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Camilleri, Virginie, E-mail: virginie.camilleri@irsn.fr [Institut de Radioprotection et de SÛreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Cavalie, Isabelle, E-mail: isabelle.cavalie@irsn.fr [Institut de Radioprotection et de SÛreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Floriani, Magali, E-mail: magali.floriani@irsn.fr [Institut de Radioprotection et de SÛreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); and others

    2017-03-15

    Highlights: • The parental DU-exposure induced a significant transfer of uranium into eggs. • Du-exposed progeny exhibited a significant 2-fold increased DNA methylation level. • The transcriptomic response was deeply modified in the DU-exposed organisms. • DU-exposed adult and offspring presented significant histopathological injuries. - Abstract: This study investigated the effects of adult zebrafish exposure to a nominal concentration of 20 μg L{sup −1} of depleted uranium (DU) for six days upon DNA methylation, gene expression and the appearance of histopathological damage in their progeny. In the embryos at the 2–8 cell stage, the parental exposure induced significant DU accumulation, with levels seven times higher than those measured in the control embryos, but in larvae 96 h post-fertilisation (hpf), uranium concentration had already returned to a level identical to that of the control larvae. A significant two-fold increase in the global level of DNA methylation was observed in embryos as early as the prim5 (24 hpf) stage and was still maintained at the 96 hpf stage despite the fact that DU had already been depurated at the later stage. RNA sequencing analysis indicated an impact of parental exposure upon the total RNAs transmitted from the mother to eggs, and the up-regulated genes were those associated with post-traductional protein modification and trafficking and cellular signalling pathways, whereas the down-regulated genes concerned the translational process, cell cycle regulation and several cell signalling pathways. Alterations of photoreceptor cells and the axon-axon junctions between photoreceptors were observed in the eyes of adult fish exposed for 10 days to DU. Actin and myosin filament disorganisation was observed in the skeletal muscles of 96 hpf larvae, at a stage when the maternally transmitted DU had already been excreted. These data reveal the extreme sensitivity of zebrafish embryos to DU transmitted through the oocyte by

  16. Epigenetic, histopathological and transcriptomic effects following exposure to depleted uranium in adult zebrafish and their progeny

    International Nuclear Information System (INIS)

    Gombeau, Kewin; Bourdineaud, Jean-Paul; Ravanat, Jean-Luc; Armant, Olivier; Camilleri, Virginie; Cavalie, Isabelle; Floriani, Magali

    2017-01-01

    Highlights: • The parental DU-exposure induced a significant transfer of uranium into eggs. • Du-exposed progeny exhibited a significant 2-fold increased DNA methylation level. • The transcriptomic response was deeply modified in the DU-exposed organisms. • DU-exposed adult and offspring presented significant histopathological injuries. - Abstract: This study investigated the effects of adult zebrafish exposure to a nominal concentration of 20 μg L −1 of depleted uranium (DU) for six days upon DNA methylation, gene expression and the appearance of histopathological damage in their progeny. In the embryos at the 2–8 cell stage, the parental exposure induced significant DU accumulation, with levels seven times higher than those measured in the control embryos, but in larvae 96 h post-fertilisation (hpf), uranium concentration had already returned to a level identical to that of the control larvae. A significant two-fold increase in the global level of DNA methylation was observed in embryos as early as the prim5 (24 hpf) stage and was still maintained at the 96 hpf stage despite the fact that DU had already been depurated at the later stage. RNA sequencing analysis indicated an impact of parental exposure upon the total RNAs transmitted from the mother to eggs, and the up-regulated genes were those associated with post-traductional protein modification and trafficking and cellular signalling pathways, whereas the down-regulated genes concerned the translational process, cell cycle regulation and several cell signalling pathways. Alterations of photoreceptor cells and the axon-axon junctions between photoreceptors were observed in the eyes of adult fish exposed for 10 days to DU. Actin and myosin filament disorganisation was observed in the skeletal muscles of 96 hpf larvae, at a stage when the maternally transmitted DU had already been excreted. These data reveal the extreme sensitivity of zebrafish embryos to DU transmitted through the oocyte by exposed

  17. Cadmium speciation and accumulation in periphyton in a small stream with dynamic concentration variations

    Energy Technology Data Exchange (ETDEWEB)

    Bradac, Philippe [Eawag, Swiss Federal Institute of Aquatic Science and Technology, P.O. Box 611, CH-8600 Duebendorf (Switzerland); ETH, Swiss Federal Institute of Technology, Department of Environmental Sciences, CH-8092 Zurich (Switzerland); Wagner, Bettina; Kistler, David; Traber, Jacqueline; Behra, Renata [Eawag, Swiss Federal Institute of Aquatic Science and Technology, P.O. Box 611, CH-8600 Duebendorf (Switzerland); Sigg, Laura, E-mail: laura.sigg@eawag.c [Eawag, Swiss Federal Institute of Aquatic Science and Technology, P.O. Box 611, CH-8600 Duebendorf (Switzerland); ETH, Swiss Federal Institute of Technology, Department of Environmental Sciences, CH-8092 Zurich (Switzerland)

    2010-03-15

    Accumulation of cadmium in periphyton was investigated under field conditions while Cd concentration and speciation were dynamically varying in a small stream during rain events. Speciation in water was determined in situ by diffusion gradient in thin-films (DGT) and by modeling of complexation with fulvic acids. During the rain events, dissolved Cd concentrations increased from 0.17 nM to 0.27-0.36 nM, and 70-97% were DGT-labile. Cd content in periphyton closely followed Cd concentrations in water, despite higher concentrations of Zn and Mn, and may be controlled by either free or DGT-labile Cd concentrations. Decrease of Cd content in periphyton after the rain events was slower than the decrease of Cd concentration in water. Concentrations of Zn, Mn, Cu, Pb and Fe in periphyton also followed the dynamic variations of metal concentrations in water. Repeated exposure of periphyton to elevated dissolved Cd may lead to Cd accumulation. - Cadmium accumulation in periphyton was examined in a small stream during rain events in relation to Cd speciation.

  18. Cadmium speciation and accumulation in periphyton in a small stream with dynamic concentration variations

    International Nuclear Information System (INIS)

    Bradac, Philippe; Wagner, Bettina; Kistler, David; Traber, Jacqueline; Behra, Renata; Sigg, Laura

    2010-01-01

    Accumulation of cadmium in periphyton was investigated under field conditions while Cd concentration and speciation were dynamically varying in a small stream during rain events. Speciation in water was determined in situ by diffusion gradient in thin-films (DGT) and by modeling of complexation with fulvic acids. During the rain events, dissolved Cd concentrations increased from 0.17 nM to 0.27-0.36 nM, and 70-97% were DGT-labile. Cd content in periphyton closely followed Cd concentrations in water, despite higher concentrations of Zn and Mn, and may be controlled by either free or DGT-labile Cd concentrations. Decrease of Cd content in periphyton after the rain events was slower than the decrease of Cd concentration in water. Concentrations of Zn, Mn, Cu, Pb and Fe in periphyton also followed the dynamic variations of metal concentrations in water. Repeated exposure of periphyton to elevated dissolved Cd may lead to Cd accumulation. - Cadmium accumulation in periphyton was examined in a small stream during rain events in relation to Cd speciation.

  19. Genetic variation in tolerance of Douglas-fir to Swiss needle cast as assessed by symptom expression.

    Science.gov (United States)

    G.R. Jonhson

    2002-01-01

    The incidence of Swiss needle cast on Douglas-fir has increased significantly in recent years on the Oregon coast. Genetic variation in symptoms of disease infection, as measured by foliage traits, was assessed in two series of progeny trials to determine whether these "crown health" indicators were under genetic control and correlated with tolerance;...

  20. Estimation of the variations of ventilation rate and indoor radon concentration using the observed wind velocity and indoor-outdoor temperature difference

    International Nuclear Information System (INIS)

    Nagano, Katsuhiro; Inose, Yuichi; Kojima, Hiroshi

    2006-01-01

    The indoor radon concentration in the building depends on the ventilation rate. Measurement results of indoor-outdoor pressure difference showed the ventilation rate correlated closely with the indoor-outdoor pressure difference. The observation results showed that one of factor of indoor-outdoor pressure difference was the wind velocity. When the wind velocity is small, the ventilation rate is affected by the indoor-outdoor temperature difference and the effect depends on the wind velocity. The temporal variation of indoor radon concentration was predicted by the time depending indoor radon balance model and the ventilation rate estimated from the wind velocity and the indoor-outdoor temperature difference. The temporal variations of predicted radon concentration gave good agreement with the experimental values. The measurement method, indoor radon concentration and ventilation rate, factors of temporal variation of ventilation rate, and prediction of indoor radon concentration are reported. (S.Y.)

  1. Prediction of lung cells oncogenic transformation for induced radon progeny alpha particles using sugarscape cellular automata.

    Science.gov (United States)

    Baradaran, Samaneh; Maleknasr, Niaz; Setayeshi, Saeed; Akbari, Mohammad Esmaeil

    2014-01-01

    Alpha particle irradiation from radon progeny is one of the major natural sources of effective dose in the public population. Oncogenic transformation is a biological effectiveness of radon progeny alpha particle hits. The biological effects which has caused by exposure to radon, were the main result of a complex series of physical, chemical, biological and physiological interactions. The cellular and molecular mechanisms for radon-induced carcinogenesis have not been clear yet. Various biological models, including cultured cells and animals, have been found useful for studying the carcinogenesis effects of radon progeny alpha particles. In this paper, sugars cape cellular automata have been presented for computational study of complex biological effect of radon progeny alpha particles in lung bronchial airways. The model has included mechanism of DNA damage, which has been induced alpha particles hits, and then formation of transformation in the lung cells. Biomarkers were an objective measure or evaluation of normal or abnormal biological processes. In the model, the metabolism rate of infected cell has been induced alpha particles traversals, as a biomarker, has been followed to reach oncogenic transformation. The model results have successfully validated in comparison with "in vitro oncogenic transformation data" for C3H 10T1/2 cells. This model has provided an opportunity to study the cellular and molecular changes, at the various stages in radiation carcinogenesis, involving human cells. It has become well known that simulation could be used to investigate complex biomedical systems, in situations where traditional methodologies were difficult or too costly to employ.

  2. An Alpha spectrometer for measuring radon daughter individual activity concentration

    International Nuclear Information System (INIS)

    Berico, M.; Formignani, M.; Mariotti, F.

    2001-01-01

    In the frame of the program of the Institute for Radiation Protection of ENEA, related to the evaluation of dose from radon and thoron progeny, an alpha spectrometer for the continuous air monitoring (CAM type) of radon and thoron has been realized. The constructive characteristics of the device are here presented together with energy and efficiency calibration. The device allows, by means of a screen type diffusion battery and a filter, to determinate the single radioactivity of each radionuclide of the progeny selecting them in relation to their diffusive behaviour (dichotomous particle size selection). The three-count filter method has been employed to measure the concentrations of 218 Po, 214 Pb and 214 Bi in air. Radon and thoron effective doses using a dosimetric, instead of an epidemiologic approach, will be then evaluated [it

  3. Suppression of local haze variations in MERIS images over turbid coastal waters for retrieval of suspended sediment concentration

    NARCIS (Netherlands)

    Shen, F.; Verhoef, W.

    2010-01-01

    Atmospheric correction over turbid waters can be problematic if atmospheric haze is spatially variable. In this case the retrieval of water quality is hampered by the fact that haze variations could be partly mistaken for variations in suspended sediment concentration (SSC). In this study we propose

  4. Spread of Hepatitis B Viruses In Vitro Requires Extracellular Progeny and May Be Codetermined by Polarized Egress

    Science.gov (United States)

    Funk, A.; Hohenberg, H.; Mhamdi, M.; Will, H.; Sirma, H.

    2004-01-01

    Viruses can spread by different mechanisms: via intracellular particles through cell junctions to neighboring cells or via secreted virions to adjacent or remote cells. The observation of clusters of hepadnavirus-infected cells both in vivo and in primary hepatocytes neither proves the first mechanism nor excludes the second. In order to test which mechanism, if not both, is used by hepatitis B viruses in order to spread, we used primary duck hepatocytes and duck hepatitis B virus (DHBV) as an infection model. If extracellular progeny virus alone determines spreading, neutralizing antisera or drugs blocking virus binding to hepatocytes should abolish secondary infection. In order to test this, we used DHBV envelope-specific neutralizing antisera, as well as suramin, a known inhibitor of infection. Both reagents strongly reduced hepatocellular attachment of viral particles and almost completely abolished primary infection, whereas an ongoing intracellular infection was not affected as long as no progeny virus was released. In contrast, incubation of infected primary hepatocytes with these reagents during release of progeny virus completely prevented secondary infection. Moreover, the combination of electron and immunofluorescence microscopy analyses revealed the residence of viral particles in cytoplasmic vesicles preferentially located near the basolateral membrane of infected hepatocytes. Taken together, these data strongly suggest that hepatitis B viruses mainly spread by secreted, extracellular progeny and point to polarized egress of viral particles into intercellular compartments, which restricts their diffusion and favors transmission of virus to adjacent cells. PMID:15047813

  5. ANÁLISIS ESPACIAL DE VARIANZA COMO ALTERNATIVA DE EVALUACIÓN DE ENSAYOS DE PROGENIES FORESTALES

    Directory of Open Access Journals (Sweden)

    Victor Morales

    2016-01-01

    Full Text Available El uso del diseño en bloques y la aleatori - zación de las diferentes progenies en cada uno de los bloques puede ser insuficiente para el control local de la variación dentro del área del ensayo. La presencia de micro-sitios dispersos influyen en el crecimiento de los individuos, incidiendo de forma importante sobre los resultados del análisis de varianza convencional. El presente trabajo propone y describe una metodología de análisis para ensayos de progenie en la investigación forestal, que compara varios procedimientos de análisis espacial de varianzas con referencia a incorporar o no el efecto de bloque y el modelado de la tendencia superficial sobre datos registra - dos provenientes de un ensayo de Progenies de Pachira quinata (Jacq. W.S. Alverson por un periodo de 3 años de evaluación. Se estableció un protocolo de análisis que incluye diagnósti - co de correlación de los residuales, modelado de la estructura de correlación-variación y un análisis de varianza espacial. Se demostró la existencia de residuales o errores experimentales que no cumplen el supuesto de independencia, requisito fundamental para realizar un análisis de la varianza basado en diseño. El modelo con mejor ajuste fue aquel que capturó la variación superficial mediante el polinómico cúbico con el modelado de los errores correlacionados (modelo geoestadístico esférico. Las pruebas de medias de progenies estimadas por el modelo espacial con tendencia polinómica arrojó un ordenamiento diferente a las pruebas de medias estimadas bajo el análisis basado en diseño en bloques.

  6. Generation of viable progeny from dead brooders of endangered catfish Clarias magur (Hamilton, 1822

    Directory of Open Access Journals (Sweden)

    Sullip Kumar Majhi

    2017-10-01

    Full Text Available The obligatory air-breathing catfish Clarias magur is a prime candidate for aquaculture owing to its unique taste, high growth rate, and hardy nature. However, recently the IUCN has listed the species under the endangered category because the population has critically declined in the wild. The sexually mature C. magur brooders are often collected from their natural habitats for seed production in captivity. In many cases, the brooder dies due to handling injuries or confinement stress. In this study, we demonstrated that viable progeny could be generated from freshly dead sexually mature C. magur. Three hours after death, the gonads were excised, macroscopically examined and gamete viability was evaluated. Artificial fertilization was performed by mixing the sperm suspension with the eggs. Water was added after 1 min of mixing to activate the fertilization process. We observed 85%-93% fertilization success from gametes derived from dead donors as opposed to 90%-95% from those derived from live control donors. The embryos showed normal development and resulted in the generation of 88%-92% viable progeny, which was similar to the progeny derived from control donors (92%-93%. The results obtained in this study will have profound implications in enhancing the seed production of endangered C. magur and could potentially be applied to other key commercially or endangered fish species. Keywords: Biological sciences, Developmental biology, Zoology

  7. Long-term variations of man-made radionuclide concentrations in a bio-indicator Mytilus galloprovincialis from the French Mediterranean coast

    International Nuclear Information System (INIS)

    Charmasson, S.; Barker, E.; Calmet, D.; Pruchon, A.S.; Thebault, H.

    1999-01-01

    Results from a 14-year monitoring (1984-1997) of man-made radionuclide (137Cs and 106Ru) levels in Mytilus galloprovincialis collected monthly on the French Mediterranean coast are presented. In this area sources of man-made radionuclides are on the one hand atmospheric fallout from both the past nuclear testings and the Chernobyl accident and on the other hand discharges from nuclear installations located on the Rhone River banks, especially those from the spent nuclear fuel reprocessing plant in Marcoule. Long-term variations of radionuclide concentrations in Mytilus demonstrated seasonal variations which are linked to the reproductive cycle of these organisms as well as to variations in land-based inputs of man-made radionuclides. A comparative study of these seasonal variations has been carried out with the aid of spectral analysis. Due to differences in released activities and discharge patterns, flow rates appear to govern mainly the 137Cs variations in the Rhone waters, whereas 106Ru variations are driven by the discharges. In the area under the influence of the Rhone outflow, 137Cs variations in mussels are characterized by seasonal variations which are themselves inversely correlated with variations of 137Cs concentrations in Rhone waters. This cyclic component seems to be closely linked to the mussel reproductive cycle. The possible influence of other parameters is discussed

  8. Estimating seasonal variations in cloud droplet number concentration over the boreal forest from satellite observations

    NARCIS (Netherlands)

    Janssen, R.; Ganzeveld, L.N.; Kabat, P.; Kulmala, M.; Nieminen, T.; Roebeling, R.A.

    2011-01-01

    Seasonal variations in cloud droplet number concentration (NCD) in low-level stratiform clouds over the boreal forest are estimated from MODIS observations of cloud optical and microphysical properties, using a sub-adiabatic cloud model to interpret vertical profiles of cloud properties. An

  9. Variation of atmospheric tritium concentration in three chemical forms at Toki, Japan: 2004-12.

    Science.gov (United States)

    Tanaka, M; Uda, T

    2015-11-01

    Atmospheric tritium concentrations of HTO, HT and CH3T have been measured at Toki, Japan, for the environmental impact assessment of tritium for a fusion test facility. According to the data from 2004 to 2012, the concentrations of HT and HTO in water vapour tend to increase in spring. The seasonal variation in HT concentration at Toki was compared with the H2 concentration between 1990 and 2005 at Tae-ahn Peninsula, Republic of Korea, which is at approximately the same latitude as Toki. The monthly average of HT-specific activity varied from 1.24 × 10(5) to 1.76 × 10(5) TU. The peak of the monthly average H2 concentration did not match that of HT. This indicates that the mechanism of the production or the source of HT might be different from the production mechanism of H2. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Temporal Variation of Ambient PM10 Concentration within an Urban-Industrial Environment

    Science.gov (United States)

    Wong, Yoon-Keaw; Noor, Norazian Mohamed; Izzah Mohamad Hashim, Nur

    2018-03-01

    PM10 concentration in the ambient air has been reported to be the main pollutant affecting human health, particularly in the urban areas. This research is conducted to study the variation of PM10 concentration at the three urban-industrial areas in Malaysia, namely Shah Alam, Kuala Terengganu and Melaka. In addition, the association and correlation between PM10 concentration and other air pollutants will be distinguished. Five years interval dataset (2008-2012) consisting of PM10, SOX, NOX and O3 concentrations and other weather parameters such as wind speed, humidity and temperature were obtained from Department of Environment, Malaysia. Shah Alam shows the highest average of PM10 concentration with the value of 62.76 μg/m3 in June, whereas for Kuala Terengganu was 59.29 μg/m3 in February and 46.61 μg/m3 in August for Melaka. Two peaks were observed from the time series plot using the averaged monthly PM10 concentration. First peak occurs when PM10 concentration rises from January to February and the second peak is reached in June and remain high for the next two consecutive months for Shah Alam and Kuala Terengganu. Meanwhile the second peak for Melaka is only achieved in August as a result of the transboundary of smoke from forest fires in the Sumatra region during dry season from May to September. Both of the pollutants can be sourced from rapid industrial activities at Shah Alam. PM10 concentration is strongly correlated with carbon monoxide concentration in Kuala Terengganu and Melaka with value of r2 = 0.1725 and 0.2744 respectively. High carbon monoxide and PM10 concentration are associated with burning of fossil fuel from increased number of vehicles at these areas.

  11. Measuring variation of indoor radon concentration using bare nuclear tracks detectors, scintillation counters and surface barrier detectors

    International Nuclear Information System (INIS)

    Ishak, I.; Mahat, R.H.; Amin, Y.M.

    1996-01-01

    Bare LRI 15 nuclear track detectors , scintillators counter and surface barrier detectors were used to measured the indoor radon concentration in various location within two rooms. Spatial variation of the radon concentration is caused by positioning of the door, windows, furniture, cracks in the building and also distances from floor, wall and ceiling. It is found that the change in temperature are causing radon concentration to increase at certain time of the day

  12. Variations in 137Cs activity concentrations in individual fruitbodies in clusters of Cantharellus tubaeformis

    International Nuclear Information System (INIS)

    Nikolova, I.; Johanson, K.J.

    1999-01-01

    Fruitbodies of Cantharellus tubaeformis grown in clusters were collected from a normal Swedish coniferous forest. In the laboratory, individual fruitbodies were transferred into plastic vials and the 137 Cs activity concentrations were determined and expressed as Bq kg -1 fresh weight. After drying at 55 o , the 137 CS levels were recalculated and expressed as Bq kg -1 dry weight. Large variations of 137 Cs activity concentrations between individual fruitbodies within the clusters were observed. In 1995, the range in the 137 CS levels of individual fruitbodies in one cluster were from 9,194 to 164,811 and in another cluster from 2,338 to 38,377 Bq kg -1 . The mean values for these two clusters were 90,294 and 13,556 Bq kg -1 respectively. In 1998, the mean value for eight clusters showed a range from 26,373 to 67,281 Bq kg -1 . The largest variations between individual fruitbodies within a cluster were from 11,875 to 107,160 Bq kg -1 . Refs. 10 (author)

  13. Comparison of outdoor activity size distributions of 220 Rn and 222 Rn progeny and their Influences on lung dosimetry distributions

    International Nuclear Information System (INIS)

    Mohamed, A.; El-Hussein, A.; Ahmed, A.

    2005-01-01

    In the case of internally deposited radionuclides, direct measurement of the energy absorbed from ionizing radiation emitted by the decaying radionuclides is rarely, if ever, possible. Therefore, one must rely on dosimetric models to obtain estimates of the spatial and temporal patterns of energy deposition in human lung. T These models always need some information about the parameters of activity size distributions of thoron and radon progeny. In the present work, the attached and unattached activity size distributions of thoron and radon progeny were measured in outdoor air of El-Minia, Egypt. The attached samples were collected using a low pressure Berner cascade impactor technique, while a constructed screen diffusion b attery was used for collecting the unattached samples. Most of the attached activities for 222 Rn and 220 Rn progeny were associated with the aerosol particles of the accumulation mode. The activity size distribution of thoron progeny was found to be shifted to slightly smaller particle size, compared to radon progeny. An analytical method has been developed to compute the local energy deposition of 2l2 Bi alpha particles in a target volume of 1 jam spheres located at different depths in bronchial epithelium. In order to reach the target, alpha particles travel either through tissue alone (near-wall dose) or through air and tissue (far-wall dose). It was found that the contribution of near-wall dose is higher than that of the far wall dose. While the depth-dose distributions for nuclides uniformly distributed within the epithelium are practically constant with

  14. Impacts of interannual variation of the East Asian winter monsoon on aerosol concentrations over eastern China

    Science.gov (United States)

    Zhu, J.; Liao, H.; Li, J.; Feng, J.

    2012-04-01

    China has been experiencing increased concentrations of aerosols, commonly attributed to the large increases in emissions associated with the rapid economic development. We apply a global three-dimensional Goddard Earth Observing System chemical transport model (GEOS-Chem) driven by the NASA/GEOS-4 assimilated meteorological data to quantify the impacts of East Asian winter monsoon (EAWM) on the aerosol concentrations over eastern China. We found that the simulated aerosol concentrations over eastern China have strong interannual variation and negative correlations with the strength of EAWM. Model results show that, accounting for sulfate, nitrate, ammonium, black carbon, and organic carbon aerosols, the winter surface layer PM2.5 concentration averaged over eastern China (110°-125°E, 20°-45°N) can be 17.97% (4.78 µg m-3) higher in the weak monsoon years than that in the strong monsoon years. Regionally, the weakening of EAWM is shown to be able to increase PM2.5 concentration in the middle and lower reach of the Yellow River by 12 µg m-3. This point indicates that climate change associated with variation of EAWM has an essential influence on worsening air quality over eastern China. The possible causes of higher aerosol concentrations in the weak monsoon years may be attributed to the changing in wind fields and planetary boundary layer height between the weak and strong monsoon years. Sensitivity studies are performed to identify the role of chemical reaction associated with temperature and humidity on the higher aerosol concentrations in the weak monsoon years over eastern China.

  15. Influence of diurnal variation and fasting on serum iron concentrations in a community-based population.

    Science.gov (United States)

    Nguyen, Leonard T; Buse, Joshua D; Baskin, Leland; Sadrzadeh, S M Hossein; Naugler, Christopher

    2017-12-01

    Serum iron is an important clinical test to help identify cases of iron deficiency or overload. Fluctuations caused by diurnal variation and diet are thought to influence test results, which may affect clinical patient management. We examined the impact of these preanalytical factors on iron concentrations in a large community-based cohort. Serum iron concentration, blood collection time, fasting duration, patient age and sex were obtained for community-based clinical testing from the Laboratory Information Service at Calgary Laboratory Services for the period of January 2011 to December 2015. A total of 276,307 individual test results were obtained. Iron levels were relatively high over a long period from 8:00 to 15:00. Mean concentrations were highest at blood collection times of 11:00 for adult men and 12:00 for adult women and children, however iron levels peaked as late as 15:00 in teenagers. With regard to fasting, iron levels required approximately 5h post-prandial time to return to a baseline, except for children and teenage females where no significant variation was seen until after 11h fasting. After 10h fasting, iron concentrations in all patient groups gradually increased to higher levels compared to earlier fasting times. Serum iron concentrations remain reasonably stable during most daytime hours for testing purposes. In adults, blood collection after 5 to 9h fasting provides a representative estimate of a patient's iron levels. For patients who have fasted overnight, i.e. ≥12h fasting, clinicians should be aware that iron concentrations may be elevated beyond otherwise usual levels. Copyright © 2017. Published by Elsevier Inc.

  16. Spatial and Seasonal Variation of dissolved organic carbon (DOC) concentrations in Irish streams: importance of soil and topography characteristics.

    Science.gov (United States)

    Liu, Wen; Xu, Xianli; McGoff, Nicola M; Eaton, James M; Leahy, Paul; Foley, Nelius; Kiely, Gerard

    2014-05-01

    Dissolved organic carbon (DOC) concentrations have increased in many sites in Europe and North America in recent decades. High DOC concentrations can damage the structure and functions of aquatic ecosystems by influencing water chemistry. This study investigated the spatial and seasonal variation of DOC concentrations in Irish streams across 55 sites at seven time occasions over 1 year (2006/2007). The DOC concentrations ranged from 0.9 to 25.9 mg/L with a mean value of 6.8 and a median value of 5.7 mg/L and varied significantly over the course of the year. The DOC concentrations from late winter (February: 5.2 ± 3.0 mg/L across 55 sites) and early spring (April: 4.5 ± 3.5 mg/L) had significantly lower DOC concentrations than autumn (October: mean 8.3 ± 5.6 mg/L) and early winter (December: 8.3 ± 5.1 mg/L). The DOC production sources (e.g., litterfall) or the accumulation of DOC over dry periods might be the driving factor of seasonal change in Irish stream DOC concentrations. Analysis of data using stepwise multiple linear regression techniques identified the topographic index (TI, an indication of saturation-excess runoff potential) and soil conditions (organic carbon content and soil drainage characteristics) as key factors in controlling DOC spatial variation in different seasons. The TI and soil carbon content (e.g., soil organic carbon; peat occurrence) are positively related to DOC concentrations, while well-drained soils are negatively related to DOC concentrations. The knowledge of spatial and seasonal variation of DOC concentrations in streams and their drivers are essential for optimum riverine water resources management.

  17. Analysis of disconnected diallel mating designs II: results from a third generation progeny test of the New Zealand radiata pine improvement programme.

    Science.gov (United States)

    J.N. King; M.J. Carson; G.R. Johnson

    1998-01-01

    Genetic parameters from a second generation (F2) disconnected diallel progeny test of the New Zealand radiata pine improvement programme are presented. Heritability estimates of growth and yield traits of 0.2 are similar to progeny test results of the previous generation (F1) generation tests. A trend of declining dominance...

  18. Proceedings of radon and radon progeny measurements in Australia symposium

    International Nuclear Information System (INIS)

    Akber, R.A.; Harris, F.

    1994-01-01

    This publication contain papers presented at a symposium on radon and radon progeny measurements in Australia, held in Canberra on 18 February 1994. The emphasis was on results of measurements in different exposure situations, however information on methodology and techniques was also included. The scope of the symposium expanded through participation by scientists from China, French Polynesia and New Zealand. A list of participants and their organizations is included at the end of the proceedings. refs., tabs., figs

  19. Measurement of unattached aerosols of 222 Rn progeny by means of an electrostatic deposition method

    International Nuclear Information System (INIS)

    Canoba, Analia C.; Lopez, Fabio O.

    2001-01-01

    A method for the measurement of unattached radon progeny based on its electrostatic deposition onto wire screens, using only one pump, has been implemented and calibrated. The importance of being able of making use of this method is related with the special radiological significance that has the unattached fraction of the short-lived radon progeny. Because of this, the assesment of exposure could be directly related to dose with far greater accuracy than before.The advantages of this method are its simplicity, even with the tools needed for the sample collection, as well as the measurement instruments used. Also, the suitability of this method is enhanced by the fact that it can effectively be used with a simple measuring procedure such as the Kusnetz method. (author)

  20. A novel modelling approach for spatial and temporal variations in nitrate concentrations in an N-impacted UK small upland river basin

    International Nuclear Information System (INIS)

    Smart, Richard P.; Cresser, Malcolm S.; Calver, Louise J.; Clark, Matthew; Chapman, Pippa J.

    2005-01-01

    Monthly data for 11 moorland streams displaying marked seasonality and spatial variation in nitrate concentrations have been used with readily available catchment characteristics to develop a method for predicting stream water nitrate concentrations throughout an upland river network in the Lake District, UK. Over a 12-month period, a simple asymmetric truncated cosine function of day number is used to describe seasonality effects on stream water nitrate concentrations. This is then adjusted to compensate for differences in seasonality effects with catchment elevation. Occurrence of greater proportions of steeper slopes (>20 deg. -40 deg. ) in individual catchments facilitated nitrate leaching, as did increased extent of occurrence of outcropping rocks. It is shown that the spatial and temporal variation in nitrate concentration through the river network studied may therefore be effectively represented by an equation which is a function of day number, % outcropping rock and % of catchment area with a >20 deg. -40 deg. slope. - A novel model of spatial and temporal variations in stream water nitrate concentration throughout an N-impacted upland catchment is described

  1. Spatial variation of epoxyscillirosidine concentrations in Moraea pallida (yellow tulp in South Africa

    Directory of Open Access Journals (Sweden)

    Christo J. Botha

    2013-05-01

    Full Text Available Moraea pallida (yellow tulp poisoning is economically the most important intoxication of livestock in South Africa. Poisoning varies according to locality, climatic conditions and growth stage of the plant. The primary objective of this study was to determine the concentration of the toxic principle, epoxyscillirosidine, in yellow tulp leaves and to ascertain the variability of epoxyscillirosidine concentrations within and between different locations. A secondary objective was to utilise Geographic Information Systems in an attempt to explain the variability in toxicity. Flowering yellow tulp plants were collected at 26 sampling points across 20 districts of South Africa. The leaves of five plants per sampling point were extracted and submitted for liquid chromatography/mass spectrometry analysis. A large variation in mean epoxyscillirosidine concentrations, ranging from 3.32 μg/g – 238.27 μg/g, occurred between different geographical regions. The epoxyscillirosidine concentrations also varied tremendously between individual plants (n= 5 collected at the same sampling point, with up to a 24 times difference between the lowest and highest concentration detected. No generalised correlation between epoxyscillirosidine concentrations and soil elemental concentrations could be established. However, samples obtained from the north-eastern part of the sampling region tended to have higher epoxyscillirosidine concentrations compared to samples obtained from the south-western part of the sampling region. Higher toxin concentrations in the northeast were associated with statistically significant higher soil concentrations of iron, bismuth, bromide, cadmium, chromium, rubidium, tellurium, thallium, titanium and zinc, whilst soil concentrations of strontium and soil pH, were significantly lower. This study corroborated the contention that epoxyscillirosidine concentration in yellow tulp fluctuates and may explain the variability in toxicity.

  2. Distribution and seasonal variation of concentrations of particulate carbohydrates and uronic acids in the northern Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Khodse, V.B.; Fernandes, L.; Gopalakrishna, V.V.; Bhosle, N.B.; Fernandes, V.; Matondkar, S.G.P.; Bhushan, R.

    particulate carbohydrate (TPCHO), total particulate uronic acid (TPURA) and total particulate neutral carbohydrate (TPNCHO) concentrations and composition. Strong spatial, temporal and depth related variations were evident in the distribution...

  3. Progeny Density and Nest Availability Affect Parasitism Risk and Reproduction in a Solitary Bee (Osmia lignaria) (Hymenoptera: Megachilidae).

    Science.gov (United States)

    Farzan, Shahla

    2018-02-08

    Gregarious nesting behavior occurs in a broad diversity of solitary bees and wasps. Despite the prevalence of aggregative nesting, the underlying drivers and fitness consequences of this behavior remain unclear. I investigated the effect of two key characteristics of nesting aggregations (cavity availability and progeny density) on reproduction and brood parasitism rates in the blue orchard bee (Osmia lignaria Say) (Hymenoptera: Megachilidae), a solitary species that nests gregariously and appears to be attracted to nesting conspecifics. To do so, I experimentally manipulated nest cavity availability in a region of northern Utah with naturally occurring populations of O. lignaria. Nest cavity availability had a negative effect on cuckoo bee (Stelis montana Cresson) (Hymenoptera: Megachilidae) parasitism rates, with lower parasitism rates occurring in nest blocks with more available cavities. For both S. montana and the cleptoparasitic blister beetle Tricrania stansburyi Haldeman (Coleoptera: Meloidae), brood parasitism rate was negatively correlated with log-transformed O. lignaria progeny density. Finally, cavity availability had a positive effect on male O. lignaria body weight, with the heaviest male progeny produced in nest blocks with the most cavities. These results suggest that cavity availability and progeny density can have substantial effects on brood parasitism risk and reproduction in this solitary bee species. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Seasonal variations of 222Rn concentrations in the air of a tunnel located in Nagano City

    International Nuclear Information System (INIS)

    Muramatsu, H.; Tashiro, Y.; Hasegawa, N.; Misawa, C.; Minami, M.

    2000-01-01

    The survey of 222 Rn concentrations in the air of tunnels constructed during World War II at Nagano City has been performed using a solid-state nuclear track detector technique. Concentrations of several thousands Bq m -3 were observed at inner most areas of the tunnel. A seasonal variation was clearly observed; in summer, several times higher concentrations than in winter were observed, which may be due to a stack effect induced by the temperature difference between the tunnel air and the outside air in each season. The concentrations of radon in the tunnel air decrease exponentially towards the openings of the tunnel, which indicates that the radon concentration in the tunnel is basically governed by diffusion and mixing of radon gas with air. (author)

  5. Spatial and time variations of radon-222 concentration in the atmosphere of a dead-end horizontal tunnel

    International Nuclear Information System (INIS)

    Richon, Patrick; Perrier, Frederic; Sabroux, Jean-Christophe; Trique, Michaeel; Ferry, Cecile; Voisin, Vincent; Pili, Eric

    2004-01-01

    The concentration of radon-222 has been monitored since 1995 in the atmosphere of a 2 m transverse dimension, 128 m long, dead-end horizontal tunnel located in the French Alps, at an altitude of 1600 m. Most of the time, the radon concentration is stable, with an average value ranging from 200 Bq m -3 near the entrance to about 1000 Bq m -3 in the most confined section, with an equilibrium factor between radon and its short-lived decay products varying from 0.61 to 0.78. However, radon bursts are repeatedly observed, with amplitudes reaching up to 36 x 10 3 Bq m -3 and durations varying from one to several weeks, with similar spatial variations along the tunnel as the background concentration. These spatial variations are qualitatively interpreted in terms of natural ventilation. Comparing the radon background concentration with the measured radon exhalation flux at the wall yields an estimate of 8 ± 2 x 10 -6 s -1 (0.03 ± 0.007 h -1 ) for the ventilation rate. The hypothesis that the bursts could be due to transient changes in ventilation can be ruled out. Thus, the bursts are the results of transient increased radon exhalation at the walls, that could be due to meteorological effects or possibly combined hydrological and mechanical forcing associated with the water level variations of the nearby Roselend reservoir lake. Such studies are of interest for radiation protection in poorly ventilated underground settings, and, ultimately, for a better understanding of radon exhalation associated with tectonic or volcanic processes

  6. SENSITIVITY OF MORNINGGLORY PLANTS AND THEIR PROGENIES TO GLUFOSINATE AMMONIUM

    OpenAIRE

    BRITO, I.P.F.S.; MORAES, C.P.; MARCHESI, B.B.; CARBONARI, C.A.; VELINI, E.D.

    2017-01-01

    ABSTRACT The sensitivity of weed species to herbicides is variable, and the behavior can be repeated or not in the next generation. The objective of this study was to evaluate the response of morningglory plants to different doses of glufosinate ammonium and the sensitivity of plant populations and their progenies to the herbicide. Three studies were conducted, all in a greenhouse and repeated in two periods. In the first study, two experiments were conducted to examine the dose-response curv...

  7. Regionalization based on spatial and seasonal variation in ground-level ozone concentrations across China.

    Science.gov (United States)

    Cheng, Linjun; Wang, Shuai; Gong, Zhengyu; Li, Hong; Yang, Qi; Wang, Yeyao

    2018-05-01

    Owing to the vast territory of China and strong regional characteristic of ozone pollution, it's desirable for policy makers to have a targeted and prioritized regulation and ozone pollution control strategy in China based on scientific evidences. It's important to assess its current pollution status as well as spatial and temporal variation patterns across China. Recent advances of national monitoring networks provide an opportunity to insight the actions of ozone pollution. Here, we present rotated empirical orthogonal function (REOF) analysis that was used on studying the spatiotemporal characteristics of daily ozone concentrations. Based on results of REOF analysis in pollution seasons for 3years' observations, twelve regions with clear patterns were identified in China. The patterns of temporal variation of ozone in each region were separated well and different from each other, reflecting local meteorological, photochemical or pollution features. A rising trend in annual averaged Eight-hour Average Ozone Concentrations (O 3 -8hr) from 2014 to 2016 was observed for all regions, except for the Tibetan Plateau. The mean values of annual and 90 percentile concentrations for all 338 cities were 82.6±14.6 and 133.9±25.8μg/m 3 , respectively, in 2015. The regionalization results of ozone were found to be influenced greatly by terrain features, indicating significant terrain and landform effects on ozone spatial correlations. Among 12 regions, North China Plain, Huanghuai Plain, Central Yangtze River Plain, Pearl River Delta and Sichuan Basin were realized as priority regions for mitigation strategies, due to their higher ozone concentrations and dense population. Copyright © 2017. Published by Elsevier B.V.

  8. Individual variation in p53 and Cip1 expression profiles in normal human fibroblast strains following exposure to high-let radiation

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, T.R.; Johnson, N.F.; Gilliland, F.D. [Univ. of New Mexico, Albuquerque, NM (United States)] [and others

    1995-12-01

    Exposure to {alpha}-particles emitted by radon progeny appears to be the second-leading cause of lung cancer mortality. However, individual susceptibility to the carcinogenic effects of {alpha}-particles remains poorly characterized. Variation in susceptibility to cancer produced by certian classes of DNA-damaging chemicals is suspected to involve differences in metabolic activation and detoxication. Susceptibility to {alpha}-particle-induced cancer may involve variations in capacity or opportunity to repair DNA damage. Subtle variations in DNA repair capacity would more likely explain radon-related lung cancer susceptibility. The p53 tumor suppressor protein accumulates as a cellular response to DNA damage from ionizing radiation and regulates arrest in the G{sub 1} portion of the cell cycle. Arrest in G{sub 1} portion of the cell cycle. While upstream regulation of p53 protein stability is poorly understood, variations in the ability to accumulate p53 following DNA damage represent potential variations in lung cancer susceptibility related to radon progeny. Further, transcription of the cell-cycle regulatory gene Cip1 is regulated by p53 and increases following ionizing radiation. Therefore, variations in the expression of Cip1 following {alpha}-particle exposure may also be a susceptibility factor in radon-related lung cancers. The purpose of the present investigation was to measure p53 and Cip1 protein induction following {alpha}-particle exposure of fibroblast lines from nine individuals to determine if there were significant variations. The expression of Cip1 protein indicates the differences in response are biologically relevant.

  9. Individual variation in p53 and Cip1 expression profiles in normal human fibroblast strains following exposure to high-let radiation

    International Nuclear Information System (INIS)

    Carpenter, T.R.; Johnson, N.F.; Gilliland, F.D.

    1995-01-01

    Exposure to α-particles emitted by radon progeny appears to be the second-leading cause of lung cancer mortality. However, individual susceptibility to the carcinogenic effects of α-particles remains poorly characterized. Variation in susceptibility to cancer produced by certian classes of DNA-damaging chemicals is suspected to involve differences in metabolic activation and detoxication. Susceptibility to α-particle-induced cancer may involve variations in capacity or opportunity to repair DNA damage. Subtle variations in DNA repair capacity would more likely explain radon-related lung cancer susceptibility. The p53 tumor suppressor protein accumulates as a cellular response to DNA damage from ionizing radiation and regulates arrest in the G 1 portion of the cell cycle. Arrest in G 1 portion of the cell cycle. While upstream regulation of p53 protein stability is poorly understood, variations in the ability to accumulate p53 following DNA damage represent potential variations in lung cancer susceptibility related to radon progeny. Further, transcription of the cell-cycle regulatory gene Cip1 is regulated by p53 and increases following ionizing radiation. Therefore, variations in the expression of Cip1 following α-particle exposure may also be a susceptibility factor in radon-related lung cancers. The purpose of the present investigation was to measure p53 and Cip1 protein induction following α-particle exposure of fibroblast lines from nine individuals to determine if there were significant variations. The expression of Cip1 protein indicates the differences in response are biologically relevant

  10. A study of diurnal variations of radon and thoron concentrations in different indoor environmental conditions

    International Nuclear Information System (INIS)

    Pant, Preeti; Prasad, Mukesh; Ramola, R.C.

    2015-01-01

    The measurements for diurnal variations in radon ( 222 Rn) and thoron ( 220 Rn) concentrations were performed in the different indoor conditions of Tehri Garhwal, Uttarakhand, India by using AlphaGUARD, Portable Radon Monitor and RAD7. While selecting the dwellings, the ventilation conditions, building materials, life style of the inhabitants and their exposure time indoors were also considered. The behavior of indoor radon and thoron concentrations was observed for different type of dwellings with different environmental conditions. The measurement techniques, results obtained and comparison of the results are discussed in details. (author)

  11. Evaluation of the separation and purification of 227Th from its decay progeny by anion exchange and extraction chromatography

    International Nuclear Information System (INIS)

    Ivanov, P.I.; Collins, S.M.; Es, E.M. van; García-Miranda, M.; Jerome, S.M.; Russell, B.C.

    2017-01-01

    Thorium-227 is currently undergoing evaluation as a potential radionuclide for targeted cancer therapy, and as such a high chemical purity of the material is required. To establish a reliable procedure for radiochemical isolation of 227 Th from the parent 227 Ac and decay progeny, which includes the radiotherapeutic 223 Ra, the performance of three different separation schemes based on ion-exchange and extraction chromatography have been evaluated. The results suggest that both ion exchange and extraction chromatographic techniques can be successfully used for the separation of 227 Th from its decay progeny, however extraction chromatographic resins demonstrate favourable performance in terms of Th recovery and purification from radionuclide impurities. - Highlights: • Development of a radiochemical separation of 227 Th from residual 227Ac as well as from decay progeny. • Evaluation of ion-exchange and extraction chromatography techniques. • TEVA resin demonstrates favourable performance in terms of Th recovery and purification. • Developed method is applicable to both nuclear medicine and environmental analysis.

  12. Survey of radon concentrations in three Italian towns

    International Nuclear Information System (INIS)

    Malanca, A.; Pessina, V.; Dallara, G.

    1992-01-01

    Radon-222 was measured in 187 dwellings in Parma, Reggio Emilia, and Orvieto. Samples were collected using activated carbon canisters, placed in basements and on the upper floors for at least 48 h in the period starting from January 1989 to July 1990. Gamma spectroscopy was used for the measurement of 222 Rn and its progeny. The data for the three towns show a lognormal distribution. Owing to the high radium concentration in building materials and underlying soil, high radon concentrations were observed in Orvieto's dwellings. Additional measurements carried out in 22 public schools of Parma and Reggio Emilia showed moderate radon concentrations, while significant radon levels were recorded in 37 castles and ancient buildings in Parma and Reggio Emilia provinces

  13. Ethanol Consumption by Wistar Rat Dams Affects Selenium Bioavailability and Antioxidant Balance in Their Progeny

    Directory of Open Access Journals (Sweden)

    Olimpia Carreras

    2009-07-01

    Full Text Available Ethanol consumption affects maternal nutrition, the mothers’ antioxidant balance and the future health of their progeny. Selenium (Se is a trace element cofactor of the enzyme glutathione peroxidase (GPx. We will study the effect of ethanol on Se bioavailability in dams and in their progeny. We have used three experimental groups of dams: control, chronic ethanol and pair-fed; and three groups of pups. Se levels were measured by graphite-furnace atomic absorption spectrometry. Serum and hepatic GPx activity was determined by spectrometry. We have concluded that ethanol decreased Se retention in dams, affecting their tissue Se deposits and those of their offspring, while also compromising their progeny’s weight and oxidation balance. These effects of ethanol are caused by a reduction in Se intake and a direct alcohol-generated oxidation action.

  14. Changes in the rat lung after exposure to radon and its progeny: Effects on incorporation of bromodeoxyuridine in epithelial cells and on the incidence of nuclear aberrations in Alveolar macrophages

    International Nuclear Information System (INIS)

    Taya, A.; Morgan, A.; Baker, S.T.; Humphreys, J.A.H.; Collier, C.G.; Bisson, M.

    1994-01-01

    The aim of this study was to investigate some responses of cells in the rat respiratory tract as a function of time after inhalation exposure to various levels of radon and its progeny. Rats were exposed to a constant concentration of radon and its progeny to give cumulative exposure levels of 120, 225, 440 and 990 working level months (WLM). An additional unexposed group of rats served as controls. The end points selected for investigation were (a) the incorporation of bromodeoxyuridine (BrdU) in epithelial cells of the conducting airways and of the alveolar region of the respiratory tract and (b) the incidence of alveolar macrophages with nuclear aberrations. After exposure, the incidence of epithelial cells incorporating BrdU-the labeling index-increased in all regions of the respiratory tract examined, but the increase occurred later in alveolar than in airway epithelial cells. The highest labeling index was found in bronchial epithelial cells, which probably received the highest radiation dose. After an initial induction period, the incidence of alveolar macrophages with nuclear aberrations also increased. The possibility of using the labeling index of alveolar and airway epithelial cells, and/or the incidence of nuclear aberrations in alveolar macrophages, to estimate the radiation dose to various regions of the respiratory tract after exposure of rats to radon and its progeny is discussed. 22 refs., 3 figs., 1 tab

  15. Variation of molecular hydrogen tropospheric concentration over Southern Poland - results of the continuous chromatographic measurements.

    Science.gov (United States)

    Necki, J.; Chmura, L.

    2012-04-01

    process with precision better than 1ppb. But a temporary problems with UV lamp power supply module considerably hampers the research and adversely affect the reproducibility of the analysis. The results should be treated as a preliminary diagnosis of the diurnal and seasonal variation of the hydrogen concentration at the mountain site. The average short term variation of hydrogen concentrations does not exceed 50ppb and reveals the periodic nature except special situations when the concentration abruptly rises up by 150ppb and returns to an average of 480-520ppb. It is possible to observe the variations with larger time constant probably related with mezzo-scale circulation in atmosphere and slight seasonality in the level of hydrogen observed in autumn and in winter (with amplitude of 50ppb). Measurements carried out at Kasprowy Wierch were also used to balance the hydrogen for the city of Kraków. The work was partly financed from Polish national grant N N305 400939.

  16. The predatory mite Phytoseiulus persimilis adjusts patch-leaving to own and progeny prey needs.

    Science.gov (United States)

    Vanas, V; Enigl, M; Walzer, A; Schausberger, P

    2006-01-01

    Integration of optimal foraging and optimal oviposition theories suggests that predator females should adjust patch leaving to own and progeny prey needs to maximize current and future reproductive success. We tested this hypothesis in the predatory mite Phytoseiulus persimilis and its patchily distributed prey, the two-spotted spider mite Tetranychus urticae. In three separate experiments we assessed (1) the minimum number of prey needed to complete juvenile development, (2) the minimum number of prey needed to produce an egg, and (3) the ratio between eggs laid and spider mites left when a gravid P. persimilis female leaves a patch. Experiments (1) and (2) were the pre-requirements to assess the fitness costs associated with staying or leaving a prey patch. Immature P. persimilis needed at least 7 and on average 14+/-3.6 (SD) T. urticae eggs to reach adulthood. Gravid females needed at least 5 and on average 8.5+/-3.1 (SD) T. urticae eggs to produce an egg. Most females left the initial patch before spider mite extinction, leaving prey for progeny to develop to adulthood. Females placed in a low density patch left 5.6+/-6.1 (SD) eggs per egg laid, whereas those placed in a high density patch left 15.8+/-13.7 (SD) eggs per egg laid. The three experiments in concert suggest that gravid P. persimilis females are able to balance the trade off between optimal foraging and optimal oviposition and adjust patch-leaving to own and progeny prey needs.

  17. Azadirachtin effects on mating success, gametic abnormalities and progeny survival in Drosophila melanogaster (Diptera).

    Science.gov (United States)

    Oulhaci, Chemseddine M; Denis, Béatrice; Kilani-Morakchi, Samira; Sandoz, Jean-Christophe; Kaiser, Laure; Joly, Dominique; Aribi, Nadia

    2018-01-01

    Azadirachtin is a prominent natural pesticide and represents an alternative to conventional insecticides. It has been successfully used against insect pests. However, its effects on reproduction require further analysis. Here we investigated lethal and sublethal effects of azadirachtin, on treated adults in a model insect, Drosophila melanogaster (Meigen). Dose-mortality relationships as well as several parameters of reproduction (mating, spermatogenesis, oogenesis and fertility) were examined. Neem-Azal, a commercial formulation of azadirachtin, applied topically on newly emerged adults, increased mortality with a positive dose-dependent relationship. The LD 50 (0.63 μg) was determined 24 h after treatment using a non-linear regression. Adults surviving this dose had a mating success that was divided by 3 and a progeny production reduced by half when males were treated, and even more when females were treated. When combining probability of survival, of mating and reduced progeny, it appeared that LD 50 induced a 98% reduction in reproductive rates. Reduced progeny was partially explained by the effect of adult treatment on gametes number and abnormalities. The number of cysts and the apical nuclei positions within the cysts decreased by 29.7% and 20%, respectively, in males. In females, the number of oocytes per ovary and the volume of basal oocytes also decreased by 16.1% and 32.4%, respectively. Azadirachtin causes significant toxic effects in both sexes and decreases the fecundity and fertility of D. melanogaster. Females are more sensitive to azadirachtin. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  18. Influence of source type and air exchange on variations of indoor radon concentration

    International Nuclear Information System (INIS)

    Arvela, H.; Winqvist, K.

    1986-04-01

    The model relates radon concentration to source strength and its variations, air exchange rate and meteorological factors. Two types of sources have been studied. The pressure difference dependent source is made up of radon transported with soil pore air and driven by pressure difference due to the stack effect. The constant source is made up of radon transported by diffusion from building materials or from soil. The air exchange rate depends exponentially on indoor-outdoor temperature difference and linearly on wind speed. These two inputs have been summed in quadrature. In a house with a constant source radon concentration decreases when the air exchange rate increases due to the increasing temperature difference, whereas the pressure difference dependent source causes an increasing concentration. This is due to the fact that the effect of the source strength increase is stronger than the decreasing effect of air exchange on concentration. The winter-summer concentration ratio depends on the combination of the two types of source. A pure pressure dependent source leads to the winter-summer ratio of 2-3.5 (winter -5 deg C, summer +15 deg C, wind speed 3 m/s). A strong contribution of a constant source is needed to cause a summer concentration higher than the winter concentration. The model is in agreement with the winter-summer concentration ratios measured. This ratio increases with the increasing winter concentration. The measured ratio was near 1.0 for houses with winter concentration of 200 Bq m''3 or less and near 2.0 with concentration of 1000 Bq m''3. In a house with a constant source, the diurnal maximum occurs in the afternoon, while in houses with a pressure difference dependent source the time of maximum is early in the morning

  19. Seasonal variation of copper and zinc concentrations in the oyster Saccostrea cuccullata from the Dampier Archipelago, Western Australia: implications for pollution monitoring.

    Science.gov (United States)

    Talbot, V

    1986-12-01

    The intertidal rock oyster Saccostrea cuccullata, sampled at eight sites on eight occasions over a 1-year period, contained mean Cu and Zn concentrations ranging between 34 and 267 and 206 and 4078 mg kg-1 dry weight, respectively. In the study area, Cu and Zn emanate from sewage and boat slips (antifouling paints), while Zn probably also originates from coolant water from an electricity power generating station and iron ore exporting facilities. Highest oyster wet weight, Cu and Zn concentrations and loads occurred in January (spawning period), indicating that metal variation was not reciprocating wet weight. Lowest metal concentrations and loads occurred in October (period of onset of gametogenesis), while lowest wet weight occurred in April (post-spawning period). No significant (P less than 0.001) variation in the wet to dry weight ratio was noted temporally. However, significant, though slight, variation was noted between polluted and unpolluted oysters. Results of this study indicate that pollution control monitoring programs should consider: seasonal variation of metal concentrations; portion of the year during which standards are exceeded; oyster size and availability for human consumption; suitability of standards where shellfish are not consumed as a staple diet; appropriate size indicies which can be used for selecting specimens for intersite comparisons; wet to dry weight calculations: techniques, spatial and temporal variations; and the physical dynamics of sites used.

  20. Responses to two-way selection on growth in mass-spawned F1 progeny of Argopecten irradians concentricus (Say)

    Science.gov (United States)

    Wang, Hui; Liu, Jin; Li, Yanhong; Zhu, Xiaowen; Liu, Zhigang

    2014-03-01

    In the present study, the effect of one-generation divergent selection on the growth and survival of the bay scallop ( Argopecten irradians concentricus) was examined to evaluate the efficacy of a selection program currently being carried out in Beibu Bay in the South China Sea. A total of 146 adult scallops were randomly selected from the same cultured population of A. i. concentricus, and divided into two groups in shell length (anterior-posterior measurement): large (4.91-6.02 cm, n=74) and small (3.31-4.18 cm, n=72). At the same time, a control group was also randomly sampled (4.21-4.88 cm, n =80). Mass-spawned F 1 progenies from the three size groups were obtained and reared under identical conditions at all growth phases. The effects of two-way (or upward-downward) selection on fertilization rate, hatching rate, survival rate, daily growth in shell length and body weight were assessed in the three size groups. Results show that significant differences ( Pfertilization rate ( P>0.05), among the three groups. The hatching rate, survival rate and daily growth of the progeny of large-sized parents were greater than those of the control group ( Pbody weight were 0.32 ± 0.04 cm and 2.18 ± 0.05 g, respectively, for the upward selection, and -0.14 ± 0.03 cm and -2.77 ± 0.06 g, respectively, for the downward selection. The realized heritability estimates of shell length and body weight were 0.38 ± 0.06 cm and 0.22 ± 0.07 g for the upward selection, and 0.24 ± 0.06 cm and 0.37 ± 0.09 g for the downward selection, respectively. The change in growth by bidirectional selection suggests that high genetic variation may be present in the cultured bay scallop population in China.

  1. Comparison of indoor radon and thoron concentrations in the urban and rural dwellings of Chhattisgarh state of India

    International Nuclear Information System (INIS)

    Khokhar, M.S.K.; Kher, R.S.; Rathore, V.B.; Pandey, S.; Ramachandran, T.V.

    2008-01-01

    In the frame of nationwide radon/thoron monitoring program, indoor radon/thoron and their progeny concentrations have been estimated for 210 dwellings situated in 8 towns (urban) and 9 villages (rural) of Chhattisgarh state of India. The measurement has been made on quarterly integrating cycle for one full year in each dwelling. Twin chamber dosimeter cup with LR-115 Type-II Solid State Nuclear Track Detector was used for the measurement of indoor radon/thoron concentration. The results show that the geometric mean of indoor thoron concentration in urban dwellings varies from 11.57 to 25.88Bqm -3 with an overall geometric mean value of 16.65Bqm -3 , while in rural dwellings it varies from 12.50 to 30.08Bqm -3 with an overall geometric mean value of 19.00Bqm -3 . The potential alpha energy concentration (PAEC) levels of thoron in the urban and rural dwellings are found to be 2.58 and 4.57 mWL, respectively. Similarly, the geometric mean of indoor radon concentrations in urban dwellings is found to vary from 20.20 to 30.13Bqm -3 with an overall geometric mean value of 25.28Bqm -3 , while in rural dwellings it varies from 15.50 to 36.05Bqm -3 with an overall geometric mean value of 27.32Bqm -3 . The PAEC levels of radon in the urban and rural dwellings are found to be 1.50 and 1.87 mWL, respectively. The dose contribution of thoron and progeny in total inhalation dose has been found to be more than 20% in all the surveyed places that show the necessity to pay attention to the presence of thoron and progeny from public health point of view

  2. Transient gestational exposure to drinking water containing excess hexavalent chromium modifies insulin signaling in liver and skeletal muscle of rat progeny.

    Science.gov (United States)

    Shobana, Navaneethabalakrishnan; Aruldhas, Mariajoseph Michael; Tochhawng, Lalmuankimi; Loganathan, Ayyalu; Balaji, Sadhasivam; Kumar, Mani Kathiresh; Banu, Liaquat Alikhan Sheerin; Navin, Ajit Kumar; Mayilvanan, Chinnaiyan; Ilangovan, Ramachandran; Balasubramanian, Karundevi

    2017-11-01

    Chromium (Cr), an essential micronutrient potentiates insulin action, whereas excess hexavalent Cr (CrVI) acts as an endocrine disruptor. Pregnant mothers living in areas abutting industries using the metal and chromite ore dumps are exposed to ground water contaminated with Cr. Nevertheless, the impact of prenatal exposure to excess CrVI on insulin signaling in the progeny remains obscure. We tested the hypothesis "transient gestational exposure to drinking water containing excess CrVI may modify insulin signaling during postnatal life". Pregnant Wistar rats were given drinking water containing 50, 100 and 200 ppm CrVI (K 2 Cr 2 O 7 ) from gestational day 9-14 encompassing the period of organogenesis; the male progenies were tested at postnatal day 60. Neither fasting blood glucose nor oral glucose tolerance was altered in CrVI treated progeny. Nevertheless, western blot detection pointed out attenuated expression level of insulin receptor (IR), its downstream signaling molecules (IRS-1, pIRS-1 Tyr632 , Akt and pAkt Ser473 ) and organ specific glucose transporters (GLUT2 in liver and GLUT4 in gastrocnemius muscle), along with a significant increase in serum insulin level in male progenies exposed to CrVI. While 14 C-2-deoxy glucose uptake increased in the liver, the same decreased in the skeletal muscle whereas, 14 C-glucose oxidation recorded a consistent decrease in both tissues of CrVI exposed rats. These findings support our hypothesis and suggest that transient gestational exposure to excess CrVI may affect insulin signaling and glucose oxidation in the progeny, predictably rendering them vulnerable to insulin resistance. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Role of radon and its progeny in the origin and evolution of life on earth

    International Nuclear Information System (INIS)

    Subba Ramu, M.C.; Vohra, K.G.

    1980-01-01

    The role of natural ionising radiations from radon and its progeny in catalysing certain chemical reactions and aiding certain biological phenomena leading to the formation and evolution of life on earth is explained with illustrations. (M.G.B.)

  4. Measurement of unattached aerosols of {sup 222} Rn progeny by means of an electrostatic deposition method; Medicion de la fraccion no unida a aerosoles de la progenie de {sup 222} Rn mediante un metodo de deposicion electrostatica

    Energy Technology Data Exchange (ETDEWEB)

    Canoba, Analia C; Lopez, Fabio O [Autoridad Regulatoria Nuclear, Buenos Aires (Argentina)

    2001-07-01

    A method for the measurement of unattached radon progeny based on its electrostatic deposition onto wire screens, using only one pump, has been implemented and calibrated. The importance of being able of making use of this method is related with the special radiological significance that has the unattached fraction of the short-lived radon progeny. Because of this, the assesment of exposure could be directly related to dose with far greater accuracy than before.The advantages of this method are its simplicity, even with the tools needed for the sample collection, as well as the measurement instruments used. Also, the suitability of this method is enhanced by the fact that it can effectively be used with a simple measuring procedure such as the Kusnetz method. (author)

  5. AtHMA4 Drives Natural Variation in Leaf Zn Concentration of Arabidopsis thaliana

    Science.gov (United States)

    Chen, Zi-Ru; Kuang, Lu; Gao, Yi-Qun; Wang, Ya-Ling; Salt, David E.; Chao, Dai-Yin

    2018-01-01

    Zinc (Zn) is an essential element for plant growth and development, and Zn derived from crop plants in the diet is also important for human health. Here, we report that genetic variation in Heavy Metal-ATPase 4 (HMA4) controls natural variation in leaf Zn content. Investigation of the natural variation in leaf Zn content in a world-wide collection of 349 Arabidopsis thaliana wild collected accessions identified two accessions, Van-0 and Fab-2, which accumulate significantly lower Zn when compared with Col-0. Both quantitative trait loci (QTL) analysis and bulked segregant analysis (BSA) identified HMA4 as a strong candidate accounting for this variation in leaf Zn concentration. Genetic complementation experiments confirmed this hypothesis. Sequence analysis revealed that a 1-bp deletion in the third exon of HMA4 from Fab-2 is responsible for the lose of function of HMA4 driving the low Zn observed in Fab-2. Unlike in Fab-2 polymorphisms in the promoter region were found to be responsible for the weak function of HMA4 in Van-0. This is supported by both an expression analysis of HMA4 in Van-0 and through a series of T-DNA insertion mutants which generate truncated HMA4 promoters in the Col-0 background. In addition, we also observed that Fab-2, Van-0 and the hma4-2 null mutant in the Col-0 background show enhanced resistance to a combination of high Zn and high Cd in the growth medium, raising the possibility that variation at HMA4 may play a role in environmental adaptation. PMID:29545819

  6. AtHMA4 Drives Natural Variation in Leaf Zn Concentration of Arabidopsis thaliana.

    Science.gov (United States)

    Chen, Zi-Ru; Kuang, Lu; Gao, Yi-Qun; Wang, Ya-Ling; Salt, David E; Chao, Dai-Yin

    2018-01-01

    Zinc (Zn) is an essential element for plant growth and development, and Zn derived from crop plants in the diet is also important for human health. Here, we report that genetic variation in Heavy Metal-ATPase 4 ( HMA4 ) controls natural variation in leaf Zn content. Investigation of the natural variation in leaf Zn content in a world-wide collection of 349 Arabidopsis thaliana wild collected accessions identified two accessions, Van-0 and Fab-2, which accumulate significantly lower Zn when compared with Col-0. Both quantitative trait loci (QTL) analysis and bulked segregant analysis (BSA) identified HMA4 as a strong candidate accounting for this variation in leaf Zn concentration. Genetic complementation experiments confirmed this hypothesis. Sequence analysis revealed that a 1-bp deletion in the third exon of HMA4 from Fab-2 is responsible for the lose of function of HMA4 driving the low Zn observed in Fab-2. Unlike in Fab-2 polymorphisms in the promoter region were found to be responsible for the weak function of HMA4 in Van-0. This is supported by both an expression analysis of HMA4 in Van-0 and through a series of T-DNA insertion mutants which generate truncated HMA4 promoters in the Col-0 background. In addition, we also observed that Fab-2, Van-0 and the hma4-2 null mutant in the Col-0 background show enhanced resistance to a combination of high Zn and high Cd in the growth medium, raising the possibility that variation at HMA4 may play a role in environmental adaptation.

  7. Beneficial effect of feeding a ketogenic diet to mothers on brain development in their progeny with a murine model of pyruvate dehydrogenase complex deficiency.

    Science.gov (United States)

    Pliss, Lioudmila; Jatania, Urvi; Patel, Mulchand S

    2016-06-01

    Pyruvate dehydrogenase complex (PDC) deficiency is a major inborn error of oxidative metabolism of pyruvate in the mitochondria causing congenital lactic acidosis and primarily structural and functional abnormalities of the central nervous system. To provide an alternate source of acetyl-CoA derived from ketone bodies to the developing brain, a formula high in fat content is widely employed as a treatment. In the present study we investigated efficacy of a high-fat diet given to mothers during pregnancy and lactation on lessening of the impact of PDC deficiency on brain development in PDC-deficient female progeny. A murine model of systemic PDC deficiency by interrupting the X-linked Pdha1 gene was employed in this study. Maternal consumption of a high-fat diet during pregnancy and lactation had no effect on number of live-birth, body growth, tissue PDC activity levels, as well as the in vitro rates of glucose oxidation and fatty acid biosynthesis by the developing brain of PDC-deficient female offspring during the postnatal age 35 days, as compared to the PDC-deficient progeny born to dams on a chow diet. Interestingly, brain weight was normalized in PDC-deficient progeny of high fat-fed mothers with improvement in impairment in brain structure deficit whereas brain weight was significantly decreased and was associated with greater cerebral structural defects in progeny of chow-fed mothers as compared to control progeny of mothers fed either a chow or high fat diet. The findings provide for the first time experimental support for beneficial effects of a ketogenic diet during the prenatal and early postnatal periods on the brain development of PDC-deficient mammalian progeny.

  8. Variations of caesium isotope concentrations in air and fallout at Dalat, South Vietnam, 1986-1991

    International Nuclear Information System (INIS)

    Pham Zuy Hien; Nguyen Thanh Binh; Truong Y.; Vuong Thu Bac; Nguyen Trong Ngo.

    1993-01-01

    Monthly records of Cs-137 and Cs-134 concentrations in air and fallout at Dalat for the period 1986-1991 are presented and discussed. The concentration variations exhibit distinct maxima during December-January, when dry fallout dominated. These peaks are explained by the intrusion of more radioactive cold air masses from temperate northern latitudes during the development of large-scale anticyclones frequently observed in the most active winter monsoon period. High dry fallout velocities (about 10 cm/s) determined from this data clearly demonstrate one of the most relevant characteristics of cold air masses: behind the cold front, vertical air motion is descending

  9. Mass spectrometric studies of the cluster formation of radon progeny

    Energy Technology Data Exchange (ETDEWEB)

    Gong, S L [Toronto Univ., ON (Canada). Dept. of Chemical Engineering and Applied Chemistry

    1994-12-31

    A new experimental system is developed to study the cluster formation of radon progeny with neutral molecules in the environment, which includes a modified mass spectrometer and a surface barrier detector. With the system, the cluster research is carried out at molecular level at which the mass of individual cluster formed is measured. A theory is also proposed to treat the cluster formation as a discrete process based on the ion-dipole and dipole-dipole interactions. Comparison between the theory and experiment is given. (author). 16 refs., 6 figs.

  10. Mass spectrometric studies of the cluster formation of radon progeny

    International Nuclear Information System (INIS)

    Gong, S.L.

    1993-01-01

    A new experimental system is developed to study the cluster formation of radon progeny with neutral molecules in the environment, which includes a modified mass spectrometer and a surface barrier detector. With the system, the cluster research is carried out at molecular level at which the mass of individual cluster formed is measured. A theory is also proposed to treat the cluster formation as a discrete process based on the ion-dipole and dipole-dipole interactions. Comparison between the theory and experiment is given. (author). 16 refs., 6 figs

  11. Investigation of microbial adaptation to salinity variation for treatment of reverse osmosis concentrate by membrane bioreactor

    DEFF Research Database (Denmark)

    Jang, Duksoo; Moon, Chungman; Ahn, Kyuhong

    2014-01-01

    quantitative study on a microbial adaptation strategy for variations on salt concentration (0–20 g/L), lab-scale membrane bioreactors (7L working volume) with polypropylene hollow fiber membrane module (pore size 0.4 μm) were used with different adaptation strategies: instant and stepwise mode. The performance...

  12. Chemical segregation of progeny of camphor trees with high camphor c.q. Linalool content

    NARCIS (Netherlands)

    Khien, P.V.; Chien, Ho Trung; Dung, N.X.; Leclercq, A.X.; Leclercq, P.A.

    1998-01-01

    The propagation of open pollinated seed from two camphor trees with a high camphor and linalool content, respectively, yielded 115 progeny. The chemical composition of the leaf oils of these trees was analyzed by a combination of capillary GC and GC/MS. Four chemotypes could be distinguished among

  13. Seasonal variation in the composition and concentration of butyltin compounds in marine fish of Taiwan

    International Nuclear Information System (INIS)

    Dong, C.D.; Chen, C.W.; Liu, L.L.

    2004-01-01

    For the first time, strong evidence is presented to demonstrate that the accumulations of butyltin compounds (BTs) exhibit seasonal variations with respect to their compositions and concentrations in marine fishes. Measurements were made on the benthic ponyfish Leiogenathus splendens and lizardfish Trachinocephalus myops inhabiting the west coast of Taiwan. In the whole body samples of the ponyfish, BT concentrations ranged from 236 to 2501 ng/g wet wt, with those in winter considerably higher than in the other seasons (p summer > spring (p<0.05). Meanwhile, TBT (41%) was predominant in spring, whereas DBT (50 and 68%) was most heavily concentrated in summer and autumn (p<0.001). Seasonally mediated physiological changes, such as dilution due to growth and metabolic compensation, may play important roles in forming different BT accumulation patterns among seasons and organisms

  14. Assessment of Inhibition of Ebola Virus Progeny Production by Antiviral Compounds.

    Science.gov (United States)

    Falzarano, Darryl

    2017-01-01

    Assessment of small molecule compounds against filoviruses, such as Ebola virus, has identified numerous compounds that appear to have antiviral activity and should presumably be further investigated in animal efficacy trials. However, despite the many compounds that are purported to have good antiviral activity in in vitro studies, there are few instances where any efficacy has been reported in nonhuman primate models. Many of the high-throughput screening assays use reporter systems that only recapitulate a portion of the virus life cycle, while other assays only assess antiviral activity at relatively early time points. Moreover, many assays do not assess virus progeny production. A more in-depth evaluation of small numbers of test compounds is useful to economize resources and to generate higher quality antiviral hits. Assessing virus progeny production as late as 5 days post-infection allows for the elimination of compounds that have initial antiviral effects that are not sustained or where the virus rapidly develops resistance. While this eliminates many potential lead compounds that may be worthy of further structure-activity relationship (SAR) development, it also quickly excludes compounds that in their current form are unlikely to be effective in animal models. In addition, the inclusion of multiple assays that assess both cell viability and cell cytotoxicity, via different mechanisms, provides a more thorough assessment to exclude compounds that are not direct-acting antivirals.

  15. 220Radon (Thoron) and progeny exposures in the front-end of nuclear fuel cycle activities with special reference to radioactive minerals, thorium and rare earths processing

    International Nuclear Information System (INIS)

    Pillai, P.M.B.

    2008-01-01

    Radon is a major Source of radiation exposure both at home and work places due to its universal presence. The International Commission on Radiological Protection has always treated the radioactive noble gas radon ( 222 Rn) and its isotope thoron ( 220 Rn) as a separate subject. ICRP Publication 65 (ICRP, 1993) summarizes the current knowledge of health effects of inhaled radon and its decay products and gives recommendations/guidelines for the control of exposures due to high radon levels encountered in dwellings and work places. A major departure from earlier publications on the subject is the entirely epidemiological considerations for developing the recommendations. In work place monitoring the progeny concentrations are of primary concern than the gases themselves. However radon/thoron gas measurements may also be used provided reliable information on the equilibrium factors are available. Though many developments have taken place and many options are available for individual monitoring for radon (mainly progeny) exposures of occupational workers, a viable personal dosimeter for individual monitoring for thoron daughters is yet to materialize. The doses are mostly estimated by making use of work place monitoring data in combination with occupancy factors

  16. Repeatability of number of progeny born to bulls used in group mating of cows

    Science.gov (United States)

    The group mating of bulls in pasture situations is a management practice that might be more efficient if an individual bull’s ability to sire calves could be predicted. Retrospective data on numbers of progeny born to bulls from 4 populations (Angus and 3 composite breeds) in 4 consecutive years of...

  17. Modeling the dependency of radon concentration levels inside ancient Egyptian tombs on the ambient temperature variations

    International Nuclear Information System (INIS)

    Metwally, S.M.; Abo-Elmagdb, M.; Salamaa, E.

    2007-01-01

    Radon concentration inside partially closed places like dwellings, caves and tombs, depends on many parameters. Some parameters are known quantitatively as radon exhalation rate for walls, decay constant, surface to volume ratio and outdoor concentration while other parameters as ventilation rate is in common known qualitatively due to useless of traditional methods (tracer gases) in many places as ancient Egyptian tombs. This work introduces a derived mathematical model to evaluate the sensitivity of radon concentration levels inside single sided opening places as ancient Egyptian tombs on the ambient temperature differences. The obtained formula for the natural ventilation rate depends on the indoor and outdoor temperature difference and the geometrical dimensions of the doorway. The effects of in and out flow mixing, air viscosity, streamline contraction, swirling flow and turbulence, were taken into consideration in terms of an empirical correction factor. According UNSCEAR reports, the exhalation rate Φ=C ra λ rn fρ s (1-ε)L; C ra the effective radium content, λ rn decay constant, f emanation fraction, ρ s soil grain density, ε porosity and L diffusion length, these are approximately static parameters but the variability of ambient temperature introduces a source of energy of fluctuating strength to radon atoms in rocks which controls the flow rate and the ambient content of radon. Therefore, the change of outdoor and indoor temperature difference causes fluctuation of value and direction of volume flow rate in such places consequently causes the daily variation and on average the seasonal variation of radon concentration. Therefore according to the present model, the daily accurate expectation of radon concentrations inside ancient Egyptian tombs, require precise measurements of indoor and outdoor temperatures

  18. Spatiotemporal Variation in Mangrove Chlorophyll Concentration Using Landsat 8

    Directory of Open Access Journals (Sweden)

    Julio Pastor-Guzman

    2015-11-01

    Full Text Available There is a need to develop indicators of mangrove condition using remotely sensed data. However, remote estimation of leaf and canopy biochemical properties and vegetation condition remains challenging. In this paper, we (i tested the performance of selected hyperspectral and broad band indices to predict chlorophyll concentration (CC on mangrove leaves and (ii showed the potential of Landsat 8 for estimation of mangrove CC at the landscape level. Relative leaf CC and leaf spectral response were measured at 12 Elementary Sampling Units (ESU distributed along the northwest coast of the Yucatan Peninsula, Mexico. Linear regression models and coefficients of determination were computed to measure the association between CC and spectral response. At leaf level, the narrow band indices with the largest correlation with CC were Vogelmann indices and the MTCI (R2 > 0.5. Indices with spectral bands around the red edge (705–753 nm were more sensitive to mangrove leaf CC. At the ESU level Landsat 8 NDVI green, which uses the green band in its formulation explained most of the variation in CC (R2 > 0.8. Accuracy assessment between estimated CC and observed CC using the leave-one-out cross-validation (LOOCV method yielded a root mean squared error (RMSE = 15 mg·cm−2, and R2 = 0.703. CC maps showing the spatiotemporal variation of CC at landscape scale were created using the linear model. Our results indicate that Landsat 8 NDVI green can be employed to estimate CC in large mangrove areas where ground networks cannot be applied, and mapping techniques based on satellite data, are necessary. Furthermore, using upcoming technologies that will include two bands around the red edge such as Sentinel 2 will improve mangrove monitoring at higher spatial and temporal resolutions.

  19. Underwater in situ measurements of radionuclides in selected submarine groundwater springs, Mediterranean sea

    International Nuclear Information System (INIS)

    Tsabaris, C.; Scholten, J.; Karageorgis, A. P.; Comanducci, J. F.; Georgopoulos, D.; Liong Wee Kwong, L.; Patiris, D. L.; Papathanassiou, E.

    2010-01-01

    The application of the in situ measurement system 'KATERINA' for monitoring of radon progenies in submarine groundwater discharge (SGD) was investigated at different locations in the Mediterranean Sea (Chalkida, Stoupa, Korfos and Cabbe). At Chalkida and Stoupa radon progenies concentration exhibited almost constant values of 1.2±0.1 and 2.5±0.2 Bq l -1 , respectively. At Korfos these activities ranged between 1.4±0.1 and 2.3±0.2 Bq l -1 exhibiting inverse relationship with salinity. At Cabbe the in situ measured data were compared with radon measurements obtained by liquid scintillation counter. The system also resolved radon progeny variations of SGD on time scales above 1 h. The radioactivity levels of radon progenies from all sites were found considerably lower (approximately 2 orders of magnitude) than the commonly accepted limits for radon in drinking water. (authors)

  20. Variation of elemental concentration in hair of the Japanese in terms of age, sex and hair treatment

    International Nuclear Information System (INIS)

    Takeuchi, T.; Hayashi, T.; Takada, J.; Hayashi, Y.; Koyama, M.; Shinogi, M.; Aoki, A.; Tomiyama, T.; Katayama, K.

    1982-01-01

    Instrumental neutron activation analysis has been performed on human hair of the normal Japanese individuals to define the baseline levels of trace elements. A statistical analysis which is not influenced by detection limits, has been carried out to elucidate the variations of elemental concentrations in terms of age, sex and hair treatment. Correlation coefficients have been calculated between the logarithmic concentrations of the elements determined in the groups classified according to sex, age and hair treatment. Their significant levels have been evaluated. (author)

  1. Variation in sperm displacement and its association with accessory gland protein loci in Drosophila melanogaster.

    Science.gov (United States)

    Clark, A G; Aguadé, M; Prout, T; Harshman, L G; Langley, C H

    1995-01-01

    Genes that influence mating and/or fertilization success may be targets for strong natural selection. If females remate frequently relative to the duration of sperm storage and rate of sperm use, sperm displacement may be an important component of male reproductive success. Although it has long been known that mutant laboratory stocks of Drosophila differ in sperm displacement, the magnitude of the naturally occurring genetic variation in this character has not been systematically quantified. Here we report the results of a screen for variation in sperm displacement among 152 lines of Drosophilia melanogaster that were made homozygous for second and/or third chromosomes recovered from natural populations. Sperm displacement was assayed by scoring the progeny of cn;bw females that had been mated sequentially to cn;bw and tested males in either order. Highly significant differences were seen in both the ability to displace sperm that is resident in the female's reproductive tract and in the ability to resist displacement by subsequent sperm. Most lines exhibited nearly complete displacement, having nearly all progeny sired by the second male, but several lines had as few as half the progeny fathered by the second male. Lines that were identified in the screen for naturally occurring variation in sperm displacement were also characterized for single-strand conformation polymorphisms (SSCP) at seven accessory gland protein (Acp) genes, Glucose dehydrogenase (Gld), and Esterase-6 (Est-6). Acp genes encode proteins that are in some cases known to be transmitted to the female in the seminal fluid and are likely candidates for genes that might mediate the phenomenon of sperm displacement. Significant associations were found between particular Acp alleles at four different loci (Acp26Aa/Ab, Acp29B, Acp36DE and Acp53E) and the ability of males to resist displacement by subsequent sperm. There was no correlation between the ability to displace resident sperm and the ability

  2. Occurrence of dsRNA Mycovirus (LeV-FMRI0339 in the Edible Mushroom Lentinula edodes and Meiotic Stability of LeV-FMRI0339 among Monokaryotic Progeny

    Directory of Open Access Journals (Sweden)

    Jung-Mi Kim

    2013-12-01

    Full Text Available dsRNA was found in malformed cultures of Lentinula edodes strain FMRI0339, one of the three most popular sawdust cultivated commercial strains of shiitake, and was also found in healthy-looking fruiting bodies and actively growing mycelia. Cloning of the partial genome of the dsRNA revealed the presence of the RdRp sequence of a novel L. edodes mycovirus (LeV, and sequence comparison of the cloned amplicon showed identical sequences sequence to known RNA-dependent RNA polymerase genes of LeV found in strain HKA. The meiotic stability of dsRNA was examined by measuring the ratio of the presence of dsRNA among sexual monokaryotic progeny. More than 40% of the monokaryotic progeny still contained the dsRNA, indicating the persistence of dsRNA during sexual reproduction. Comparing the mycelia growth of monokaryotic progeny suggested that there appeared to be a tendency toward a lower frequency of virus incidence in actively growing progeny.

  3. Exploring spatial and temporal variations of cadmium concentrations in pacific oysters from british columbia.

    Science.gov (United States)

    Feng, Cindy Xin; Cao, Jiguo; Bendell, Leah

    2011-09-01

    Oysters from the Pacific Northwest coast of British Columbia, Canada, contain high levels of cadmium, in some cases exceeding some international food safety guidelines. A primary goal of this article is the investigation of the spatial and temporal variation in cadmium concentrations for oysters sampled from coastal British Columbia. Such information is important so that recommendations can be made as to where and when oysters can be cultured such that accumulation of cadmium within these oysters is minimized. Some modern statistical methods are applied to achieve this goal, including monotone spline smoothing, functional principal component analysis, and semi-parametric additive modeling. Oyster growth rates are estimated as the first derivatives of the monotone smoothing growth curves. Some important patterns in cadmium accumulation by oysters are observed. For example, most inland regions tend to have a higher level of cadmium concentration than most coastal regions, so more caution needs to be taken for shellfish aquaculture practices occurring in the inland regions. The semi-parametric additive modeling shows that oyster cadmium concentration decreases with oyster length, and oysters sampled at 7 m have higher average cadmium concentration than those sampled at 1 m. © 2010, The International Biometric Society.

  4. Variation of ascorbic acid concentration in fruits of cultivated and wild apples.

    Science.gov (United States)

    Fang, Ting; Zhen, Qiaoling; Liao, Liao; Owiti, Albert; Zhao, Li; Korban, Schuyler S; Han, Yuepeng

    2017-06-15

    Ascorbic acid (AsA) content in mature fruits of 457 apple accessions were measured, and a great variation in AsA concentration was detected. Wild fruits showed significantly higher level of AsA than cultivated fruits. Fruit AsA content was positively correlated with malic acid content, but negatively correlated with fruit weight and soluble solid content. Thus, the difference in AsA content between the wild and cultivated fruits could be attributed to an indirect consequence of human selection for larger fruit size, less acidity, and increased sweetness during apple domestication. Additionally, AsA concentration was extremely high in fruit at the juvenile stage, but dramatically decreased at the expanding and mature stages. The expression levels of three genes controlling AsA accumulation, MdGGP1, MdDHAR3-3, and MdNAT7-2, were significantly negatively correlated with AsA contents in fruits, suggesting a feedback regulation mechanism in AsA-related gene expression. Our results could be helpful for future apple breeding. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Validation of the abbreviated Radon Progeny Integrating Sampling Unit (RPISU) method for Mesa County, Colorado

    International Nuclear Information System (INIS)

    Langner, G.H. Jr.

    1987-06-01

    The US Department of Energy (DOE) Office of Remedial Action and Waste Technology established the Technical Measurements Center at the DOE Grand Junction, Colorado, Projects Office to standardize, calibrate, and compare measurements made in support of DOE remedial action programs. Indoor radon-daughter concentration measurements are made to determine whether a structure is in need of remedial action. The Technical Measurements Center conducted this study to validate an abbreviated Radon Progeny Integrated Sampling Unit (RPISU) method of making indoor radon-daughter measurements to determine whether a structure has a radon-daughter concentration (RDC) below the levels specified in various program standards. The Technical Measurements Center established a criterion against which RDC measurements made using the RPISU sampling method are evaluated to determine if sampling can be terminated or whether further measurements are required. This abbreviated RPISU criterion was tested against 317 actual sets of RPISU data from measurements made over an eight-year period in Mesa County, Colorado. The data from each location were tested against a standard that was assumed to be the same as the actual annual average RDC from that location. At only two locations was the criterion found to fail. Using the abbreviated RPISU method, only 0.6% of locations sampled can be expected to be falsely indicated as having annual average RDC levels below a given standard

  6. Morphological and cytological evaluation of progeny obtained from pollination of Fragaria x ananassa Duch. with Potentilla spp.

    Directory of Open Access Journals (Sweden)

    Katarzyna Niemirowicz-Szczytt

    2014-01-01

    Full Text Available In the second year of growth, 131 (of 159 progeny from pollination of F. X ananassa with Potentilla spp. were examined for morphological characters such as leaf shape and lay-out, the ability to produce runners, flowering, the color of flower petals, sex, ability to develop torus and viability of seeds. On the basis of these characters, among which the ability of expansion of the fleshy receptacle (torus serves to distinguish representatives of the genus Fragaria from Potentilla species, the progeny from this intergeneric pollination was considered matroclinous (850/o produce fleshy fruits and the remaining plants also show Fragaria traits. Matroclinous plants preserve traits of the maternal species, but show a variability of these characters within the species, thus;, they are not identical with the varie.ties from which they arose. Matroclinous plants differ widely in ploidy. Among the 153 examined individuals, tetraploids were most numerously represented (41%, next came penta- and hexaploids (36%, octoploids (8%, mixoploids and aneuploids (6,5%, triploids (5.5% and others. From among 199 matroclinous plants, 77 produce relatively highly viable seeds in open pollination, 33 gave seeds of low viability and 8 produced completely sterile seeds. Preliminary examination of the progeny of matroclinous plants seems to indicate that it is possible to obtain a next fertile generation.

  7. Sex determination in beetles: Production of all male progeny by Parental RNAi knockdown of transformer

    Science.gov (United States)

    Shukla, Jayendra Nath; Palli, Subba Reddy

    2012-01-01

    Sex in insects is determined by a cascade of regulators ultimately controlling sex-specific splicing of a transcription factor, Doublesex (Dsx). We recently identified homolog of dsx in the red flour beetle, Tribolium castaneum (Tcdsx). Here, we report on the identification and characterization of a regulator of Tcdsx splicing in T. castaneum. Two male-specific and one female-specific isoforms of T. castaneum transformer (Tctra) were identified. RNA interference-aided knockdown of Tctra in pupa or adults caused a change in sex from females to males by diverting the splicing of Tcdsx pre-mRNA to male-specific isoform. All the pupa and adults developed from Tctra dsRNA injected final instar larvae showed male-specific sexually dimorphic structures. Tctra parental RNAi caused an elimination of females from the progeny resulting in production of all male progeny. Transformer parental RNAi could be used to produce all male population for use in pest control though sterile male release methods. PMID:22924109

  8. Modeling the dependency of radon concentration levels inside ancient Egyptian tombs on the ambient temperature variations

    Energy Technology Data Exchange (ETDEWEB)

    Metwally, S M; Abo-Elmagdb, M [Faculty of Science, Department of Physics, Ain Shams University, P. O. Box 11566, Cairo (Egypt); Salamaa, E [National Institute for Standard, Radiation Measurements Department, Cairo (Egypt)

    2007-06-15

    Radon concentration inside partially closed places like dwellings, caves and tombs, depends on many parameters. Some parameters are known quantitatively as radon exhalation rate for walls, decay constant, surface to volume ratio and outdoor concentration while other parameters as ventilation rate is in common known qualitatively due to useless of traditional methods (tracer gases) in many places as ancient Egyptian tombs. This work introduces a derived mathematical model to evaluate the sensitivity of radon concentration levels inside single sided opening places as ancient Egyptian tombs on the ambient temperature differences. The obtained formula for the natural ventilation rate depends on the indoor and outdoor temperature difference and the geometrical dimensions of the doorway. The effects of in and out flow mixing, air viscosity, streamline contraction, swirling flow and turbulence, were taken into consideration in terms of an empirical correction factor. According UNSCEAR reports, the exhalation rate {phi}=C{sub ra}{lambda}{sub rn} f{rho}{sub s}(1-{epsilon})L; C{sub ra} the effective radium content, {lambda}{sub rn} decay constant, f emanation fraction, {rho}{sub s} soil grain density, {epsilon} porosity and L diffusion length, these are approximately static parameters but the variability of ambient temperature introduces a source of energy of fluctuating strength to radon atoms in rocks which controls the flow rate and the ambient content of radon. Therefore, the change of outdoor and indoor temperature difference causes fluctuation of value and direction of volume flow rate in such places consequently causes the daily variation and on average the seasonal variation of radon concentration. Therefore according to the present model, the daily accurate expectation of radon concentrations inside ancient Egyptian tombs, require precise measurements of indoor and outdoor temperatures.

  9. Simulation of laminar and turbulent concentric pipe flows with the isogeometric variational multiscale method

    KAUST Repository

    Ghaffari Motlagh, Yousef; Ahn, Hyungtaek; Hughes, Thomas Jr R; Calo, Victor M.

    2013-01-01

    We present an application of the residual-based variational multiscale modeling methodology to the computation of laminar and turbulent concentric annular pipe flows. Isogeometric analysis is utilized for higher-order approximation of the solution using Non-Uniform Rational B-Splines (NURBS). The ability of NURBS to exactly represent curved geometries makes NURBS-based isogeometric analysis attractive for the application to the flow through annular channels. We demonstrate the applicability of the methodology to both laminar and turbulent flow regimes. © 2012 Elsevier Ltd.

  10. Effect of natural ventilation on radon and radon progeny levels in houses. Rept. for Apr 90-Sep 91

    International Nuclear Information System (INIS)

    Cavallo, A.; Gadsby, K.; Reddy, T.A.; Socolow, R.

    1991-01-01

    The paper discusses the effect of natural ventilation on radon and radon progeny levels in houses. Contradicting the widely held assumption that ventilation is ineffective in reducing indoor radon concentrations, experiments in a research house have shown that the basement radon level can be reduced by a factor of 5 to 10 using only natural ventilation. Measurement of the outdoor-basement pressure differential and the radon entry rate shows that this unexpectedly large reduction in indoor radon levels is caused by two complementary physical processes: (1) the obvious one, dilution, which lowers radon concentrations by adding uncontaminated outdoor air; and (2) although less evident, introducing a pressure break in the system through an open basement window which, in turn, reduces the outdoor-basement pressure differential and the rate at which radon-laden soil gas is drawn into the house. The radon entry rate was found to be a linear function of basement depressurization up to a differential pressure of about 4 Pa, as would be expected for laminar soil gas flow; opening two basement windows approximately doubled the building air exchange rate and reduced the radon entry rate by up to a factor of 5

  11. Norway spruce (Picea abies Karst. variability in progeny tests in Bosnia and Herzegovina

    Directory of Open Access Journals (Sweden)

    Cvjetković Branislav

    2017-01-01

    Full Text Available Norway spruce is one of the most important economic species is Bosnia and Herzegovina. It is the species at the edge of its natural range; nevertheless it attains significant growth and yield results. The species is often used for afforestation purposes. In the previous period, 4 progeny tests of Norway spruce were established in Bosnia and Herzegovina. The offspring from 6 natural populations: Han Pijesak 1, Han Pijesak 2, Foča, Potoci, Olovo and Kneževo were build-in the progeny tests. In 2016, the samples of Norway spruce from 2 progeny tests: Srebrenica and Drinić were collected. In total, 360 samples were collected. DNA isolation was done according to Dumoline et al. (1990. For assessment of genetic differences among populations, co-dominant nSSR microsatellite system had been used. The number of effective alleles ranged from 7.78 in the population Potoci up to 15 in the population Kneževo, the average number of alleles was 13. The observed heterozygosity ranged from 0.61 for the population Han Pijesak 2 up to 0.68 for population Kneževo. The average observed heterozygosity was 0.65. Fixation index was in the range from -0.073 in the population Potoci, to 0.030 for the population Han Pijesak 2. The average value of Wright fixation index is -0.007. The average fixation index indicates the existence of a very small number of homozygotes. Concerning the variability among populations it has been concluded that the total level of genetic differentiation among populations was very low (FST= 0.026. The result of Nei’s genetic distance shows that the populations Olovo and Potoci are separated from other populations. The results obtained by genetic markers, in addition with other, morphological and physiological markers will be the basis for the further investigation of Norway spruce adaptability and possibility for the transfer of genetic material in light of climate changes.

  12. Evaluation of the degree of resistance of maternal scots pine trees and their progeny to the action of SO/sub 2/, O/sub 3/ and a mixture of these gases

    Energy Technology Data Exchange (ETDEWEB)

    Bialobok, S; Karolewski, P

    1978-01-01

    Detached shoots of trees and 10 months old seedlings from seed collected from these trees, from 17 clones of Scots pine, had been subjected to the action of sulfur dioxide, ozone and a mixture of these gases. The plants were exposed to the gases in chambers specially adapted for the purpose. The concentrations of gases used and the durations of exposition permitted a considerable differentiation of the degree of needle injury observed on individual trees. On the basis of the experiments conducted a comparison was made of the injuries to needles of mother trees and to their seedling progenies made by the various gas treatments. A significant positive correlation was observed between the injuries in mothers and in the progenies due to SO/sub 2/ and O/sub 3/ acting alone. Comparison of the injuries observed on single needles and on needle pairs in fascicles allowed us to conclude that the latter were more sensitive to the action of SO/sub 2/ while with ozone the opposite is true. 22 references, 4 figures, 5 tables.

  13. Investigation of Differences in Fertility among Progenies from Self-Pollinated Chrysanthemum

    Directory of Open Access Journals (Sweden)

    Fan Wang

    2018-03-01

    Full Text Available Most chrysanthemum cultivars are self-incompatible, so it is very difficult to create pure lines that are important in chrysanthemum breeding and theoretical studies. In our previous study, we obtained a self-compatible chrysanthemum cultivar and its self-pollinated seed set was 56.50%. It was interesting that the seed set of its ten progenies ranged from 0% to 37.23%. Examination of the factors causing the differences in the seed set will lead to an improved understanding of chrysanthemum self-incompatibility, and provide valuable information for creating pure lines. Pollen morphology, pollen germination percentage, pistil receptivity and embryo development were investigated using the in vitro culture method, the paraffin section technique, scanning electron microscopy and transmission electron microscopy. Moreover, RNA sequencing and bioinformatics were applied to analyzing the transcriptomic profiles of mature stigmas and anthers. It was found that the self-pollinated seed set of “Q10-33-1①”,”Q10-33-1③”,”Q10-33-1④” and “Q10-33-1⑩” were 37.23%, 26.77%, 7.97% and 0%, respectively. The differences in fertility among four progenies were mainly attributable to differences in pollen germination percentage and pistil receptivity. Failure of the seed set in “Q10-33-1⑩” was possibly due to self-incompatibility. In the transcriptomic files, 22 potential stigma S genes and 8 potential pollen S genes were found out.

  14. Maternal Transfer of Vitamin C in Channel Catfish (Ictalurus Punctatus) Effects Reproduction and Progeny Performance

    Science.gov (United States)

    Two routes of maternal transfer of vitamin C in channel catfish female broodfish prior to spawning were explored as a strategy to incorporate the vitamin to determine its effect on reproduction and subsequent performance of the progeny. Accumulation of vitamin C was higher (p<0.05) in ovarian tissu...

  15. Genetic changes in progeny of bystander human fibroblasts after microbeam irradiation with X-rays, protons or carbon ions: the relevance to cancer risk.

    Science.gov (United States)

    Autsavapromporn, Narongchai; Plante, Ianik; Liu, Cuihua; Konishi, Teruaki; Usami, Noriko; Funayama, Tomoo; Azzam, Edouard I; Murakami, Takeshi; Suzuki, Masao

    2015-01-01

    Radiation-induced bystander effects have important implications in radiotherapy. Their persistence in normal cells may contribute to risk of health hazards, including cancer. This study investigates the role of radiation quality and gap junction intercellular communication (GJIC) in the propagation of harmful effects in progeny of bystander cells. Confluent human skin fibroblasts were exposed to microbeam radiations with different linear energy transfer (LET) at mean absorbed doses of 0.4 Gy by which 0.036-0.4% of the cells were directly targeted by radiation. Following 20 population doublings, the cells were harvested and assayed for micronucleus formation, gene mutation and protein oxidation. Our results showed that expression of stressful effects in the progeny of bystander cells is dependent on LET. The progeny of bystander cells exposed to X-rays (LET ∼6 keV/μm) or protons (LET ∼11 keV/μm) showed persistent oxidative stress, which correlated with increased micronucleus formation and mutation at the hypoxanthine-guanine phosphoribosyl-transferase (HPRT) locus. Such effects were not observed after irradiation by carbon ions (LET ∼103 keV/μm). Interestingly, progeny of bystander cells from cultures exposed to protons or carbon ions under conditions where GJIC was inhibited harbored reduced oxidative and genetic damage. This mitigating effect was not detected when the cultures were exposed to X-rays. These findings suggest that cellular exposure to proton and heavy charged particle with LET properties similar to those used here can reduce the risk of lesions associated with cancer. The ability of cells to communicate via gap junctions at the time of irradiation appears to impact residual damage in progeny of bystander cells.

  16. The ratio of long-lived to short-lived radon-222 progeny concentrations in ground-level air

    International Nuclear Information System (INIS)

    Hoetzl, H.; Winkler, R.

    1996-01-01

    The ratio of 210 Pb air concentration to the short-lived radon ( 222 Rn) decay products concentration at ground level was investigated at a semi-rural location 10 km north of Munich, south Germany, for a period of 11 years (1982-1992). The average ratio from 132 monthly mean values has been found to be (7.5±2.2) x 10 -5 (arithmetic mean±S.D.). While the time series of the short-lived radon daughter concentration exhibit a distinct seasonal pattern with maxima mostly in October of each year, the course of 210 Pb air concentration is characterized by high values from October through February. Consequently, high ratios of 210 Pb to short-lived decay product concentration are often observed in the winter months of December-February. To study the influence of meteorological conditions on this behaviour, 210 Pb and 214 Pb concentrations were measured on a short-term basis with sampling intervals of 2-3 days from October 1991 to November 1992. The air concentrations obtained within those intervals were then correlated with actual meteorological parameters. On the base of this investigation the seasonal behaviour can essentially be explained by the more frequent inversion weather conditions in winter than in the summer months. At the same location, the average ratio of 210 Po to 210 Pb concentration in ground level air has been found to be 0.079 from 459 weakly mean values between 1976 and 1985. Hence, the corresponding average ratios of the short-lived radon daughters (EEC) to 210 Pb and 210 Po, were 1:7.5x10 -5 and 1:0.6 x 10 -5 , respectively

  17. Temporal variation in fish mercury concentrations within lakes from the western Aleutian Archipelago, Alaska.

    Directory of Open Access Journals (Sweden)

    Leah A Kenney

    Full Text Available We assessed temporal variation in mercury (Hg concentrations of threespine stickleback (Gasterosteus aculeatus from Agattu Island, Aleutian Archipelago, Alaska. Total Hg concentrations in whole-bodied stickleback were measured at two-week intervals from two sites in each of two lakes from June 1 to August 10, 2011 during the time period when lakes were ice-free. Across all sites and sampling events, stickleback Hg concentrations ranged from 0.37-1.07 µg/g dry weight (dw, with a mean (± SE of 0.55 ± 0.01 µg/g dw. Mean fish Hg concentrations declined by 9% during the study period, from 0.57 ± 0.01 µg/g dw in early June to 0.52 ± 0.01 µg/g dw in mid-August. Mean fish Hg concentrations were 6% higher in Loon Lake (0.56 ± 0.01 µg/g dw than in Lake 696 (0.53 ± 0.01 µg/g dw, and 4% higher in males (0.56 ± 0.01 µg/g dw than in females (0.54 ± 0.01 µg/g dw. Loon Lake was distinguished from Lake 696 by the presence of piscivorous waterbirds during the breeding season. Mercury concentrations in stickleback from Agattu Island were higher than would be expected for an area without known point sources of Hg pollution, and high enough to be of concern to the health of piscivorous wildlife.

  18. Temporal variation in fish mercury concentrations within lakes from the western Aleutian Archipelago, Alaska

    Science.gov (United States)

    Kenney, Leah A.; Eagles-Smith, Collin A.; Ackerman, Joshua T.; von Hippel, Frank A.

    2014-01-01

    We assessed temporal variation in mercury (Hg) concentrations of threespine stickleback (Gasterosteus aculeatus) from Agattu Island, Aleutian Archipelago, Alaska. Total Hg concentrations in whole-bodied stickleback were measured at two-week intervals from two sites in each of two lakes from June 1 to August 10, 2011 during the time period when lakes were ice-free. Across all sites and sampling events, stickleback Hg concentrations ranged from 0.37–1.07 µg/g dry weight (dw), with a mean (± SE) of 0.55±0.01 µg/g dw. Mean fish Hg concentrations declined by 9% during the study period, from 0.57±0.01 µg/g dw in early June to 0.52±0.01 µg/g dw in mid-August. Mean fish Hg concentrations were 6% higher in Loon Lake (0.56±0.01 µg/g dw) than in Lake 696 (0.53±0.01 µg/g dw), and 4% higher in males (0.56±0.01 µg/g dw) than in females (0.54±0.01 µg/g dw). Loon Lake was distinguished from Lake 696 by the presence of piscivorous waterbirds during the breeding season. Mercury concentrations in stickleback from Agattu Island were higher than would be expected for an area without known point sources of Hg pollution, and high enough to be of concern to the health of piscivorous wildlife.

  19. Submicron-sized aerosol and radon progeny measurements in an uranium mine

    International Nuclear Information System (INIS)

    Boulaud, D.; Chouard, J.C.

    1992-01-01

    Submicron-sized aerosol was studied in an uranium mine using an Electrical Aerosol Analyzer and a Differential Mobility Particle Sizer. In addition radon progeny particle size distributions were measured using a prototype instrument developed by us (SDI 2000). With cascade impactor the number weighted mean electrical mobility diameters and the geometric standard deviations ranged respectively from 0.05 to 0.1 μm and 1.8 to 2. The gross alpha activity weighted mean thermodynamic diameters ranged typically from 0.1 to 0.2 μm. 6 refs., 3 figs

  20. Measurement of the size distributions of radon progeny in indoor air

    International Nuclear Information System (INIS)

    Hopke, P.K.; Ramamurthi, M.; Li, C.S.

    1990-01-01

    A major problem in evaluating the health risk posed by airborne radon progeny in indoor atmospheres is the lack of available information on the activity-weighted size distributions that occur in the domestic environment. With an automated, semicontinuous, graded screen array system, we made a series of measurements of activity-weighted size distributions in several houses in the northeastern United States. Measurements were made in an unoccupied house, in which human aerosol-generating activities were simulated. The time evolution of the aerosol size distribution was measured in each situation. Results of these measurements are presented

  1. Changes in feed intake, growth, feed efficiency, and body composition of beef cattle fed forage then concentrate diets

    Science.gov (United States)

    The objective of this experiment was to determine changes in production traits and body composition of beef steers and heifers when fed a forage-based ration followed by a concentrate-based ration. Cattle were progeny of composite breed cows bred to Charolais, Simmental, and Red Angus bulls. Appro...

  2. RADON PROGENY AS AN EXPERIMENTAL TOOL FOR DOSIMETRY OF NANOAEROSOLS

    Energy Technology Data Exchange (ETDEWEB)

    Ruzer, Lev; Ruzer, Lev S.; Apte, Michael G.

    2008-02-25

    The study of aerosol exposure and dosimetry measurements and related quantitation of health effects are important to the understanding of the consequences of air pollution, and are discussed widely in the scientific literature. During the last 10 years the need to correlate aerosol exposure and biological effects has become especially important due to rapid development of a new, revolutionary industry ?-- nanotechnology. Nanoproduct commerce is predicted to top $1 trillion by 2015. Quantitative assessment of aerosol particle behavior in air and in lung deposition, and dosimetry in different parts of the lung, particularly for nanoaerosols, remains poor despite several decades of study. Direct measurements on humans are still needed in order to validate the hollow cast, animal studies, and lung deposition modeling. We discuss here the use of nanoscale radon decay products as an experimental tool in the study of local deposition and lung dosimetry for nanoaerosols. The issue of the safe use of radon progeny in such measurements is discussed based on a comparison of measured exposure in 3 settings: general population, miners, and in a human experiment conducted at the Paul Scherer Institute (PSI) in Switzerland. One of the properties of radon progeny is that they consist partly of 1 nm radioactive particles called unattached activity; having extremely small size and high diffusion coefficients, these particles can be potentially useful as radioactive tracers in the study of nanometer-sized aerosols. We present a theoretical and experimental study of the correlation between the unattached activity and aerosol particle surface area, together with a description of its calibration and method for measurement of the unattached fraction.

  3. The ratio of long-lived to short-lived radon-222 progeny concentrations in ground-level air

    Energy Technology Data Exchange (ETDEWEB)

    Hoetzl, H.; Winkler, R. [Institut fuer Strahlenschutz, GSF-Forschungszentrum fuer Umwelt und Gesundheit, Neuherberg Oberschleissheim (Germany)

    1996-02-09

    The ratio of {sup 210}Pb air concentration to the short-lived radon ({sup 222}Rn) decay products concentration at ground level was investigated at a semi-rural location 10 km north of Munich, south Germany, for a period of 11 years (1982-1992). The average ratio from 132 monthly mean values has been found to be (7.5{+-}2.2) x 10{sup -5} (arithmetic mean{+-}S.D.). While the time series of the short-lived radon daughter concentration exhibit a distinct seasonal pattern with maxima mostly in October of each year, the course of {sup 210}Pb air concentration is characterized by high values from October through February. Consequently, high ratios of {sup 210}Pb to short-lived decay product concentration are often observed in the winter months of December-February. To study the influence of meteorological conditions on this behaviour, {sup 210}Pb and {sup 214}Pb concentrations were measured on a short-term basis with sampling intervals of 2-3 days from October 1991 to November 1992. The air concentrations obtained within those intervals were then correlated with actual meteorological parameters. On the base of this investigation the seasonal behaviour can essentially be explained by the more frequent inversion weather conditions in winter than in the summer months. At the same location, the average ratio of {sup 210}Po to {sup 210}Pb concentration in ground level air has been found to be 0.079 from 459 weakly mean values between 1976 and 1985. Hence, the corresponding average ratios of the short-lived radon daughters (EEC) to {sup 210}Pb and {sup 210}Po, were 1:7.5x10{sup -5} and 1:0.6 x 10{sup -5}, respectively.

  4. Spatial and temporal variations of radon concentrations in groundwater of hard rock aquifers in Madurai district, India

    International Nuclear Information System (INIS)

    Thivya, C.; Chidambaram, S.; Thilagavathi, R.; Nepolian, M.; Tirumalesh, K.; Prasanna, M.V.

    2017-01-01

    Radon ("2"2"2Rn) and other radionuclides in groundwater can lead to health problems if present in higher concentrations. A study was carried out in Madurai district of Tamilnadu by collecting groundwater samples for four different seasons and aims to identify the regions with higher "2"2"2Rn concentration along with their spatial and seasonal variations. "2"2"2Rn has been compared with field parameters, log pCO_2, major ions and uranium to detect the factors responsible for the higher concentration in groundwater. The weathering process induces the release of higher uranium ions from the granitic terrain from the rock matrix which enhances the "2"2"2Rn levels in groundwater. (author)

  5. Experimental alternatives for evaluation of progenies and clones in eucalyptus breeding programs

    Directory of Open Access Journals (Sweden)

    Souza Elaine Aparecida de

    2003-01-01

    Full Text Available The feasibility of using augmented block designs and spatial analysis methods for early stage selection in eucalyptus breeding programs was tested. A total of 113 half-sib progenies of Eucalyptus urophylla and eight clones were evaluated in an 11 x 11 triple lattice experiment at two locations: Posto da Mata (Bahia, Brazil and São Mateus (Minas Gerais, Brazil. Four checks were randomly allocated within each block. Plots consisted of 15 m long rows containing 6 plants spaced 3 m apart. The girth at breast height (cm/plant was evaluated at 19 and 26 months of age. Variance analyses were performed according to the following methods: lattice design, randomized complete block design, augmented block design, Papadakis method, moving means method, and check plots. Comparisons among different methods were based on the magnitude of experimental errors and precision of the estimates of genetic and phenotypic parameters. General results indicated that augmented block design is useful to evaluate progenies and clones in early selection in eucalyptus breeding programs using moderate and low selection intensities. However, this design is not suitable for estimating genetic and phenotypic parameters due to its low precision. Check plots, nearest neighbour, Papadakis (1937, and moving means methods were efficient in removing the heterogeneity within blocks. These efficiencies were compared to that in lattice analysis for estimation of genetic and phenotypic parameters.

  6. Possible causes of variation in acrylamide concentration in French fries prepared in food service establishments: an observational study

    NARCIS (Netherlands)

    Sanny, M.A.I.; Jinap, S.; Bakker, E.J.; Boekel, van M.A.J.S.; Luning, P.A.

    2012-01-01

    Acrylamide is a probable human carcinogen, and its presence in a range of fried and oven-cooked foods has raised considerable health concern world-wide. Dietary intake studies observed significant variations in acrylamide concentrations, which complicate risk assessment and the establishment of

  7. Biological control of short-term variations in the concentration of DMSP and DMS during a Phaeocystis spring bloom

    NARCIS (Netherlands)

    van Duyl, FC; Gieskes, WWC; Kop, AJ; Lewis, WE

    1998-01-01

    In the spring of 1995. short-term variations in the concentration of particulate and dissolved dimethylsulfoniopropionate (DMSP) and dimethylsulfide (DMS) were monitored in the western Wadden Sea, a shallow coastal region in open connection with the North Sea. Significant correlations were found

  8. Radon in an underground cave system in Victoria

    International Nuclear Information System (INIS)

    Hedt, J.C.; Boal, T.J.

    1998-01-01

    Radon levels in a cave system in Victoria have been measured. The variation of radon and radon progeny levels with time, position throughout the cave and season have been determined. The radiation exposure of tour guides were estimated. The data is being used to develop a radiation management plan for the tour guides. Radon concentration within a cave system was proven to be dependent to a large extent upon the rate of air exchange with outside. Cave ventilation is the single most important factor in determining if there is diurnal variation in the radon concentration

  9. Temporal-spatial variation of DOC concentration, UV absorbance and the flux estimation in the Lower Dagu River, China

    Science.gov (United States)

    Xi, Min; Kong, Fanlong; Li, Yue; Kong, Fanting

    2017-12-01

    Dissolved organic carbon (DOC) is an important component for both carbon cycle and energy balance. The concentration, UV absorbance, and export flux of DOC in the natural environment dominate many important transport processes. To better understand the temporal and spatial variation of DOC, 7 sites along the Lower Dagu River were chosen to conduct a comprehensive measurement from March 2013 to February 2014. Specifically, water samples were collected from the Lower Dagu River between the 26th and 29th of every month during the experimental period. The DOC concentration (CDOC) and UV absorbance were analyzed using a total organic carbon analyzer and the ultraviolet-visible absorption spectrum, and the DOC export flux was estimated with a simple empirical model. The results showed that the CDOC of the Lower Dagu River varied from 1.32 to 12.56 mg/L, consistent with global rivers. The CDOC and UV absorbance showed significant spatial variation in the Dagu River during the experiential period because of the upstream natural processes and human activities in the watershed. The spatial variation is mainly due to dam or reservoir constructions, riverside ecological environment changes, and non-point source or wastewater discharge. The seasonal variation of CDOC was mainly related to the source of water DOC, river runoff, and temperature, and the UV absorbance and humification degree of DOC had no obvious differences among months ( P<0.05). UV absorbance was applied to test the CDOC in Lower Dagu River using wave lengths of 254 and 280 nm. The results revealed that the annual DOC export flux varied from 1.6 to 3.76 × 105 g C/km2/yr in a complete hydrological year, significantly lower than the global average. It is worth mentioning that the DOC export flux was mainly concentrated in summer (˜90% of all-year flux in July and August), since the runoff in the Dagu River took place frequently in summer. These observations implied environment change could bring the temporal

  10. Intraspecific variation in 137Cs activity concentration in sporocarps of Suillus variegatus in seven Swedish populations

    International Nuclear Information System (INIS)

    Dahlberg, Anders; Nikolova, Ivanka; Johanson, K.-J.

    1997-01-01

    Following the Chernobyl accident in 1986, sporocarps of Suillus variegatus in Sweden showed a large amount of individual variation in concentration of 137 Cs activity. Our aim was to determine the degrees to which this variability in sporocarp 137 Cs levels could be explained by differences between (i) local populations, (ii) fungal genets and (iii) locations within genets. Five populations in a 100-yr-old Scots pine forest, located within a 1 km 2 area, and two populations in Scots pine/Norway spruce forest, located 40 km north-west of Uppsala, were investigated. In total, 154 sporocarps were analysed to determine their 137 Cs content. Of these, the genetic affiliations of 86 were successfully characterized using somatic incompatibility reactions. Twenty-six genets were found which, on average, consisted of 6.5 sporocarps. The genets averaged 7.5 m in size, measured as the length between the most distant sporocarps. The mean sporocarp 137 Cs level was 67.1 ± 2.8 kBq kgsup(-1) D.W. (range between 13.6 and 182). According to analyses of variance, within-population variation accounted for 60% of the total variation in 137 Cs levels, while 40% was ascribed to variation among populations. Within a population, 137 Cs levels did not generally differ significantly between genets. Plausible reasons for intraspecific variation in radiocaesium content in sporocarps are discussed. (author)

  11. Spartial and seasonal variations in concentrations of polycyclic aromatic hydrocarbons in water and sediment of Kisumu City bay of Winam Gulf, Lake Victoria-Kenya.

    Science.gov (United States)

    Kwach, Bowa O; Lalah, Joseph O; Shem, Wandiga O

    2009-11-01

    Seasonal and offshore concentration variations for selected sixteen priority pollutant polycyclic aromatic hydrocarbons (PAHs) in surface sediments and water of Car Wash and Kisat areas of Winam Gulf, Lake Victoria, have been investigated. PAHs concentrations in sediments and water range from 0.4 to 31.95 microg/g dry weight and 3.32 to 55.8 microg/L, respectively. Statistical analysis of the PAHs concentrations showed that the most contaminated samples are found during rainy season (April, 2006), 5 m offshore for sediments and 10 m offshore for water. Dry season (October, 2005) generally recorded lower concentrations. The variations showed significant difference (p < or = 0.05) with season and distance of sampling from the shore.

  12. Numerical modelling of local deposition patients, activity distributions and cellular hit probabilities of inhaled radon progenies in human airways

    International Nuclear Information System (INIS)

    Farkas, A.; Balashazy, I.; Szoeke, I.

    2003-01-01

    The general objective of our research is modelling the biophysical processes of the effects of inhaled radon progenies. This effort is related to the rejection or support of the linear no threshold (LNT) dose-effect hypothesis, which seems to be one of the most challenging tasks of current radiation protection. Our approximation and results may also serve as a useful tool for lung cancer models. In this study, deposition patterns, activity distributions and alpha-hit probabilities of inhaled radon progenies in the large airways of the human tracheobronchial tree are computed. The airflow fields and related particle deposition patterns strongly depend on the shape of airway geometry and breathing pattern. Computed deposition patterns of attached an unattached radon progenies are strongly inhomogeneous creating hot spots at the carinal regions and downstream of the inner sides of the daughter airways. The results suggest that in the vicinity of the carinal regions the multiple hit probabilities are quite high even at low average doses and increase exponentially in the low-dose range. Thus, even the so-called low doses may present high doses for large clusters of cells. The cell transformation probabilities are much higher in these regions and this phenomenon cannot be modeled with average burdens. (authors)

  13. A correlation of long term effects and radiation quality in the progeny of bystander cells after microbeam radiations: The experimental study of radiotherapy for cancer risk mitigation

    Science.gov (United States)

    Autsavapromporn, N.; Konishi, T.; Liu, C.; Plante, I.; Funayama, T.; Usami, N.; Azzam, EI; Suzuki, M.

    2017-06-01

    The goal of this study is to investigate the role of radiation quality and gap junction intercellular communication (GJIC) in the propagation of delayed stressful effects in the progeny of bystander human skin fibroblasts cultures (NB1RGB). Briefly, confluent NB1RGB cells in the presence and absence of gap junction inhibitor (AGA) were exposed to ionizing radiation (IR) with a different linear energy transfer (LET) either 5.35 keV X rays (LET ∼6 keV/μm) or 18.3 MeV/u carbon (LET ∼103 keV/μm) microbeam radiations. Following 20 populations post-irradiation, the progeny of bystander NB1RGB cells were harvested and assayed for several of biological endpoints. Our results showed that expression of stressful effects in the progeny of bystander cells is dependent on LET. The progeny of bystander cells exposed to low-LET X rays showed the persistence of oxidative stress and it was correlated with the increased mutant fraction. Such effect were not observed after high-LET carbon ions. Interestingly, inhibition of GJIC mitigated the toxic effects in the progeny of bystander cells. Together, the results contribute to the understanding of the fundamental radiation biology relating to the high-LET carbon ions to mitigate cancer risk after radiotherapy. Furthermore, GJIC be considered as a critical mediator in the bystander mutagenic effect.

  14. Death losses due to stillbirth, neonatal death and diseases in cloned cattle derived from somatic cell nuclear transfer and their progeny: a result of nationwide survey in Japan.

    Science.gov (United States)

    Watanabe, Shinya; Nagai, Takashi

    2009-06-01

    To obtain the data concerning death losses due to stillbirth, neonatal death and diseases in cloned cattle derived from somatic cell nuclear transfer (SCNT) and their progeny produced by Japanese institutions, a nationwide survey was carried out in July-August, 2006. As a result, lifetime data concerning 482 SCNT cattle (97.5% of cattle produced in the country at that time) and 202 progeny of SCNT cattle were accumulated and the death loss of these cattle was analyzed. Although 1/3 of delivered SCNT calves died during the perinatal period due to stillbirth and neonatal death, incidence of death loss due to diseases in SCNT cattle surviving more than 200 days after birth seems to be the same as these in conventionally bred cattle. In contrast, progeny of SCNT cattle showed the same level in death loss as observed in conventionally bred cattle throughout their lifetime. These results suggest that robust health would be expected in SCNT cattle surviving to adulthood and their progeny.

  15. Variations of uranium concentrations in a multi-aquifer system under the impact of surface water-groundwater interaction

    Science.gov (United States)

    Wu, Ya; Li, Junxia; Wang, Yanxin; Xie, Xianjun

    2018-04-01

    Understanding uranium (U) mobility is vital to minimizing its concentrations in potential drinking water sources. In this study, we report spatial-seasonal variations in U speciation and concentrations in a multi-aquifer system under the impact of Sanggan River in Datong basin, northern China. Hydrochemical and H, O, Sr isotopic data, thermodynamic calculations, and geochemical modeling are used to investigate the mechanisms of surface water-groundwater mixing-induced mobilization and natural attenuation of U. In the study site, groundwater U concentrations are up to 30.2 μg/L, and exhibit strong spatial-seasonal variations that are related to pH and Eh values, as well as dissolved Ca2+, HCO3-, and Fe(III) concentrations. For the alkaline aquifers of this site (pH 7.02-8.44), U mobilization is due to the formation and desorption of Ca2UO2(CO3)30 and CaUO2(CO3)32- caused by groundwater Ca2+ elevation via mineral weathering and Na-Ca exchange, incorporated U(VI) release from calcite, and U(IV) oxidation by Fe(OH)3. U immobilization is linked to the adsorption of CaUO2(CO3)32- and UO2(CO3)34- shifted from Ca2UO2(CO3)30 because of HCO3- elevation and Ca2+ depletion, U(VI) co-precipitation with calcite, and U(VI) reduction by adsorbed Fe2+ and FeS. Those results are of great significance for the groundwater resource management of this and similar other surface water-groundwater interaction zones.

  16. Continuous progeny testing, use and selection of proven bulls in Israel

    Directory of Open Access Journals (Sweden)

    R. Bar-Anan

    1983-12-01

    Full Text Available The breeding policy of the Israeli Holstein-type dairy cattle is reviewed. The bulls are progeny tested on their daughters’ first three lactations. The traits evaluated are the following: milk, fat, yield persistency, fertility, incidence of mastitis, and % cullings for three most important reasons. The test analysis takes into account the genetic level of daughters’ contemporaries and maternal grandsires. The paper describes a general outline of the selection decisions in AI bulls. Considerable amount of imported semen is used for breeding young bulls. Breeding goals are discussed against the estimated genetic parameters for and between the given traits.

  17. Lake transparency: a window into decadal variations in dissolved organic carbon concentrations in Lakes of Acadia National Park, Maine

    Science.gov (United States)

    Roesler, Collin S.; Culbertson, Charles W.

    2016-01-01

    A forty year time series of Secchi depth observations from approximately 25 lakes in Acadia National Park, Maine, USA, evidences large variations in transparency between lakes but relatively little seasonal cycle within lakes. However, there are coherent patterns over the time series, suggesting large scale processes are responsible. It has been suggested that variations in colored dissolved organic matter (CDOM) are primarily responsible for the variations in transparency, both between lakes and over time and further that CDOM is a robust optical proxy for dissolved organic carbon (DOC). Here we present a forward model of Secchi depth as a function of DOC based upon first principles and bio-optical relationships. Inverting the model to estimate DOC concentration from Secchi depth observations compared well with the measured DOC concentrations collected since 1995 (RMS error < 1.3 mg C l-1). This inverse model allows the time series of DOC to be extended back to the mid 1970s when only Secchi depth observations were collected, and thus provides a means for investigating lake response to climate forcing, changing atmospheric chemistry and watershed characteristics, including land cover and land use.

  18. Feeding dried distillers grains with solubles to lactating beef cows: impact of excess protein and fat on post-weaning progeny growth, glucose tolerance and carcass traits.

    Science.gov (United States)

    Shee, C N; Lemenager, R P; Schoonmaker, J P

    2018-04-01

    insulin concentrations and area under the curve of progeny as measured by IVGTT were not affected by maternal diet (P⩾0.16). Maternal DDGS supplementation decreased marbling score (P=0.04), but did not influence carcass grading percentage or any other carcass characteristic (P⩾0.17).

  19. Dietary manipulation of the sow milk does not influence the lipid absorption capacity of the progeny

    DEFF Research Database (Denmark)

    Lauridsen, Charlotte; Hedemann, Mette Skou; Pierzynowski, Stefan

    2007-01-01

    A control diet without supplemental fat and four diets containing 8% of coconut oil, rapeseed oil, fish oil or sunflower oil were fed to lactating sows in order to investigate the lipid absorption capacity of their progeny in terms of pancreatic enzyme activity, hormonal regulation, and bile salt...

  20. How do air ions reflect variations in ionising radiation in the lower atmosphere in a boreal forest?

    Directory of Open Access Journals (Sweden)

    X. Chen

    2016-11-01

    Full Text Available Most of the ion production in the atmosphere is attributed to ionising radiation. In the lower atmosphere, ionising radiation consists mainly of the decay emissions of radon and its progeny, gamma radiation of the terrestrial origin as well as photons and elementary particles of cosmic radiation. These types of radiation produce ion pairs via the ionisation of nitrogen and oxygen as well as trace species in the atmosphere, the rate of which is defined as the ionising capacity. Larger air ions are produced out of the initial charge carriers by processes such as clustering or attachment to pre-existing aerosol particles. This study aimed (1 to identify the key factors responsible for the variability in ionising radiation and in the observed air ion concentrations, (2 to reveal the linkage between them and (3 to provide an in-depth analysis into the effects of ionising radiation on air ion formation, based on measurement data collected during 2003–2006 from a boreal forest site in southern Finland. In general, gamma radiation dominated the ion production in the lower atmosphere. Variations in the ionising capacity came from mixing layer dynamics, soil type and moisture content, meteorological conditions, long-distance transportation, snow cover attenuation and precipitation. Slightly similar diurnal patterns to variations in the ionising capacity were observed in air ion concentrations of the cluster size (0.8–1.7 nm in mobility diameters. However, features observed in the 0.8–1 nm ion concentration were in good connection to variations of the ionising capacity. Further, by carefully constraining perturbing variables, a strong dependency of the cluster ion concentration on the ionising capacity was identified, proving the functionality of ionising radiation in air ion production in the lower atmosphere. This relationship, however, was only clearly observed on new particle formation (NPF days, possibly indicating that charges after

  1. Temporal variability of the quality of Taraxacum officinale seed progeny from the East-Ural radioactive trace: is there an interaction between low level radiation and weather conditions?

    Science.gov (United States)

    Pozolotina, Vera N; Antonova, Elena V

    2017-03-01

    The multiple stressors, in different combinations, may impact differently upon seed quality, and low-level doses of radiation may enhance synergistic or antagonistic effects. During 1991-2014 we investigated the quality of the dandelion (Taraxacum officinale s.l.) seed progeny growing under low-level radiation exposure at the East-Ural Radioactive Trace (EURT) area (result of the Kyshtym accident, Russia), and in plants from areas exposed to background radiation. The viability of the dandelion seed progeny was assessed according to chronic radiation exposure, accounting for the variability of weather conditions among years. Environmental factors (temperature, precipitation, and their ratio in different months) can modify the radiobiological effects. We found a wide range of possible responses to multiple stressors: inhibition, stimulation, and indifferent effects in different seasons. The intraspecific variability of the quality of dandelion seed progeny was greatly increased under conditions of low doses of chronic irradiation. Temperature was the most significant factor for seed progeny formation in the EURT zone, whereas the sums of precipitation and ratios of precipitation to temperature dominantly affected organisms from the background population.

  2. Determination of Lung-to-Blood Absorption Rates for Lead and Bismuth which are Appropriate for Radon Progeny

    International Nuclear Information System (INIS)

    Marsh, J.W.; Birchall, A.

    1999-01-01

    The ICRP Publication 66 Human Respiratory Tract Model (HRTM) treats clearance as a competitive process between absorption into blood and particle transport to the gastrointestinal tract and lymphatics. The ICRP recommends default absorption rates for lead and bismuth in ICRP Publication 71 but states that the values are not appropriate for short-lived radon progeny. This paper describes an evaluation of published data from volunteer experiments to estimate the absorption half-times of lead and bismuth that are appropriate for short-lived radon progeny. The absorption half-time for lead was determined to be 10±2 h, based on 212 Pb lung and blood retention data from several studies. The absorption half-time for bismuth was estimated to be about 13 h, based on 212 Bi urinary excretion data from one experiment and the ICRP biokinetic model for bismuth as a decay product of lead. (author)

  3. Spatial and temporal variation of THg concentrations in run-off water from 19 boreal catchments, 2000–2010

    International Nuclear Information System (INIS)

    Eklöf, Karin; Fölster, Jens; Sonesten, Lars; Bishop, Kevin

    2012-01-01

    Total mercury concentrations are presented for 19 Swedish watercourses 2000–2010, together with an analysis of factors affecting these concentrations in space and time. Organic matter (OM) measured as absorbance at 420 nm (Abs 420 ) and total organic carbon (TOC) were the variables most strongly correlated with THg concentrations in the pooled dataset from all 19 watercourses, explaining 66% and 61% of the variance respectively. The correlation between THg and OM indicates that OM is the main controlling factor independent of geographical variation in Hg deposition, geology, or any other factor evaluated in this study. Despite an increase in TOC concentrations at most sites during the study period, THg increased in only one of the watercourses, and the THg/TOC ratio decreased significantly at six sites. The Abs 420 did not increase like TOC. We suggest that OM-fractions absorbing at 420 nm are more important for Hg mobilization than other OM-fractions. - Highlights: ► THg was measured bimonthly 2000–2010 from 19 watercourses across Sweden. ► OM quantity and quality explained most of the THg variation in space and time. ► Despite a temporal increase of TOC in most sites, THg increased in just one. ► THg was more strongly correlated with Abs 420 than TOC. - Despite strong spatial similarity in the THg/TOC ratio across large gradients of climate, land use and deposition, THg did not follow the temporal TOC trends in individual watercourses.

  4. Study of a Greek area with enhanced indoor radon concentrations

    International Nuclear Information System (INIS)

    Louizi, A.; Nikolopoulos, D.; Koukouliou, V.; Kehagia, K.

    2003-01-01

    In this paper the focus is on Arnea Chalkidikis, an area in Greece with granitic geological background and indications of possible elevated radon concentration indoors. Data are reported of indoor radon measurements with etched track detectors and those used for dosimetric estimations. Moreover, data are reported on soil gas and soil radon concentrations in Arnea, as well as radon and uranium concentrations in water samples. From the measured radon concentrations in water samples the contribution to the overall dose has been calculated. For a period of 1 month, indoor radon and progeny activity has also been monitored in the dwelling that has the maximum indoor radon concentration in Greece. This dwelling is in Arnea and the dose delivered to the inhabitants has been calculated. Mean annual effective dose due to indoor radon was 4.5 mSv and about 11% of this was due to the use of water. Mean soil gas concentration and soil radon concentration were (90 ± 30) kBq m -3 (P -3 (P -1 (P<0.05). (author)

  5. Radon Progenies as a Source of Gross Alpha-beta Activities in Drinking Water in Vinaninkarena, Antsirabe-Madagascar

    International Nuclear Information System (INIS)

    Raoelina Andriambololona; Rabesiranana, N.; Rasolonirina, M.; Rakotomanga, H.

    2004-01-01

    The village of Vinaninkarena, Antsirabe, Madagascar is located in a high radioactivity area. With the aim of assessing the health impact of radioactivity pollution, a survey was conducted around an abandoned radium mining. Waters from 24 sampling points, including 5 wells and 13 springs were sampled. The water radioactivity was measured using a portable Triathler LSC, model 425-034 from Hidex Turku. Each sample is counted more than 3 times: less than 2h after sampling, 4h to few days and more than 3 weeks after when 226 Ra attains equilibrium with 222 Rn and its short-lived daughters. Combination of water non miscible, radon extractive LS cocktail and water miscible one is used to reveal contribution of radium, radon and its short lived progenies to the gross alpha-beta activities. Maximum activity values found are : 3.6±0.3 Bq.L -1 for 226 Ra, 554±9 Bq.L -1 for the excess of radon, and 408±8 Bq.L -1 for the excess of radon progenies. Based on these data, a daily consumption of 2 L of these waters by a standard person would produce an annual 226 Ra ingestion well above the annual intake limit for 226 Ra. Moreover, the increasing gross alpha-beta activity resulting from radon progenies raises the issue of health effects. The potential for rapid spring-to-mouth delivery, which is frequent in rural area, may expose the water consumer to the short-lived alpha particle emitters.

  6. Spatial variation of particle number concentration in school microscale environments and its impact on exposure assessment.

    Science.gov (United States)

    Salimi, Farhad; Mazaheri, Mandana; Clifford, Sam; Crilley, Leigh R; Laiman, Rusdin; Morawska, Lidia

    2013-05-21

    It has not yet been established whether the spatial variation of particle number concentration (PNC) within a microscale environment can have an effect on exposure estimation results. In general, the degree of spatial variation within microscale environments remains unclear, since previous studies have only focused on spatial variation within macroscale environments. The aims of this study were to determine the spatial variation of PNC within microscale school environments, in order to assess the importance of the number of monitoring sites on exposure estimation. Furthermore, this paper aims to identify which parameters have the largest influence on spatial variation as well as the relationship between those parameters and spatial variation. Air quality measurements were conducted for two consecutive weeks at each of the 25 schools across Brisbane, Australia. PNC was measured at three sites within the grounds of each school, along with the measurement of meteorological and several other air quality parameters. Traffic density was recorded for the busiest road adjacent to the school. Spatial variation at each school was quantified using coefficient of variation (CV). The portion of CV associated with instrument uncertainty was found to be 0.3, and, therefore, CV was corrected so that only noninstrument uncertainty was analyzed in the data. The median corrected CV (CVc) ranged from 0 to 0.35 across the schools, with 12 schools found to exhibit spatial variation. The study determined the number of required monitoring sites at schools with spatial variability and tested the deviation in exposure estimation arising from using only a single site. Nine schools required two measurement sites and three schools required three sites. Overall, the deviation in exposure estimation from using only one monitoring site was as much as 1 order of magnitude. The study also tested the association of spatial variation with wind speed/direction and traffic density, using partial

  7. Influence of sire breed on the interplay among rumen microbial populations inhabiting the rumen liquid of the progeny in beef cattle.

    Directory of Open Access Journals (Sweden)

    Emma Hernandez-Sanabria

    Full Text Available This study aimed to evaluate whether the host genetic background impact the ruminal microbial communities of the progeny of sires from three different breeds under different diets. Eighty five bacterial and twenty eight methanogen phylotypes from 49 individuals of diverging sire breed (Angus, ANG; Charolais, CHA; and Hybrid, HYB, fed high energy density (HE and low energy density (LE diets were determined and correlated with breed, rumen fermentation and phenotypic variables, using multivariate statistical approaches. When bacterial phylotypes were compared between diets, ANG offspring showed the lowest number of diet-associated phylotypes, whereas CHA and HYB progenies had seventeen and twenty-three diet-associated phylotypes, respectively. For the methanogen phylotypes, there were no sire breed-associated phylotypes; however, seven phylotypes were significantly different among breeds on either diet (P<0.05. Sire breed did not influence the metabolic variables measured when high energy diet was fed. A correlation matrix of all pairwise comparisons among frequencies of bacterial and methanogen phylotypes uncovered their relationships with sire breed. A cluster containing methanogen phylotypes M16 (Methanobrevibacter gottschalkii and M20 (Methanobrevibacter smithii, and bacterial phylotype B62 (Robinsoniella sp. in Angus offspring fed low energy diet reflected the metabolic interactions among microbial consortia. The clustering of the phylotype frequencies from the three breeds indicated that phylotypes detected in CHA and HYB progenies are more similar among them, compared to ANG animals. Our results revealed that the frequency of particular microbial phylotypes in the progeny of cattle may be influenced by the sire breed when different diets are fed and ultimately further impact host metabolic functions, such as feed efficiency.

  8. Effect of concentration variation in graphene oxide (GO) membranes for water flux optimization

    Science.gov (United States)

    Kumar, Shani; Garg, Amit; Chowdhuri, Arijit

    2018-05-01

    Graphene oxide, sister material of Graphene has generated tremendous research interest in fields of energy storage, catalyst material, adsorbent material for heavy metals and dyes, green energy production, drug delivery agent, a gas sensing material as well as in membrane based water purification and desalination systems1-3 etc. In this paper, we are reporting the effect of concentration variation in GO membranes on water flux. GO has been synthesized by Hummer's method with related characterizations like XRD, Raman, SEM and FTIR carried out. GO membranes have been developed using pressure assisted filtration assembly (Water Vac-100) over Cellulose Acetate membrane support (47 mm dia. and 0.45 µm pore size), Millipore.

  9. Age and sex variation in serum albumin concentration: an observational study.

    Science.gov (United States)

    Weaving, Gary; Batstone, Gifford F; Jones, Richard G

    2016-01-01

    In the UK, a common reference interval for serum albumin is widely used irrespective of age or sex. Implicit in this is that laboratories produce analytically similar results. This paper challenges the validity of this approach. A three-week collection of results sent to all primary care centres in England has been analysed by age, sex and laboratory. In all, 1,079,193 serum albumin reports were included in this analysis. The mean population serum albumin concentration increases to peak at around age 20 years and then decreases with increasing age. Values in females decrease more rapidly but become close to male values at 60 years. The variation between laboratories was large and potentially clinically significant. Reference intervals for serum albumin should be stratified by age and sex. Until there is greater methodological standardization, laboratories should determine their own reference intervals and not accept a single consensus reference interval. © The Author(s) 2015.

  10. Epistasis between QTLs for bone density variation in Copenhagen × dark agouti F2 rats

    Science.gov (United States)

    Liu, Lixiang; Alam, Imranul; Sun, Qiwei; Econs, Michael J.; Foroud, Tatiana; Turner, Charles H.

    2010-01-01

    The variation in several of the risk factors for osteoporotic fracture, including bone mineral density (BMD), has been shown to be strongly influenced by genetic differences. However, the genetic architecture of BMD is complex in both humans and in model organisms. We previously reported quantitative trait locus (QTL) results for BMD from a genome screen of 828 F2 progeny of Copenhagen and dark agouti rats. These progeny also provide an excellent opportunity to search for epistatic effects, or interaction between genetic loci, that contribute to fracture risk. Microsatellite marker data from a 20-cM genome screen was analyzed along with weight-adjusted bone density (DXA and pQCT) phenotypic data using the R/qtl software package. Genotype and phenotype data were permuted to determine genome-wide significance thresholds for the full model and epistasis (interaction) LOD scores corresponding to an alpha level of 0.01. A novel locus on chromosome 15 and a previously reported chromosome 14 QTL demonstrated a strong epistatic effect on BMD at the femur by DXA (LOD = 5.4). Two novel QTLs on chromosomes 2 and 12 were found to interact to affect total BMD at the femur midshaft by pQCT (LOD = 5.0). These results provide new information regarding the mode of action of previously identified QTL in the rat, as well as identifying novel loci that act in combination with known QTL or with other novel loci to contribute to BMD variation. PMID:19153792

  11. Epistasis between QTLs for bone density variation in Copenhagen x dark agouti F2 rats.

    Science.gov (United States)

    Koller, Daniel L; Liu, Lixiang; Alam, Imranul; Sun, Qiwei; Econs, Michael J; Foroud, Tatiana; Turner, Charles H

    2009-03-01

    The variation in several of the risk factors for osteoporotic fracture, including bone mineral density (BMD), has been shown to be strongly influenced by genetic differences. However, the genetic architecture of BMD is complex in both humans and in model organisms. We previously reported quantitative trait locus (QTL) results for BMD from a genome screen of 828 F2 progeny of Copenhagen and dark agouti rats. These progeny also provide an excellent opportunity to search for epistatic effects, or interaction between genetic loci, that contribute to fracture risk. Microsatellite marker data from a 20-cM genome screen was analyzed along with weight-adjusted bone density (DXA and pQCT) phenotypic data using the R/qtl software package. Genotype and phenotype data were permuted to determine genome-wide significance thresholds for the full model and epistasis (interaction) LOD scores corresponding to an alpha level of 0.01. A novel locus on chromosome 15 and a previously reported chromosome 14 QTL demonstrated a strong epistatic effect on BMD at the femur by DXA (LOD = 5.4). Two novel QTLs on chromosomes 2 and 12 were found to interact to affect total BMD at the femur midshaft by pQCT (LOD = 5.0). These results provide new information regarding the mode of action of previously identified QTL in the rat, as well as identifying novel loci that act in combination with known QTL or with other novel loci to contribute to BMD variation.

  12. The spatial and temporal variation of total suspended solid concentration in Pearl River Estuary during 1987-2015 based on remote sensing.

    Science.gov (United States)

    Wang, Chongyang; Li, Weijiao; Chen, Shuisen; Li, Dan; Wang, Danni; Liu, Jia

    2018-03-15

    The movement and migration of total suspended solid (TSS) are the essential component of global material cycling and change. Based on the TSS concentrations retrieved from 112 scenes of Landsat remote sensing imageries during 1987-2015, the spatial and temporal variations of TSS concentration in high flow season and low flow seasons of six sub-regions (west shoal, west channel, middle shoal, east channel, east shoal and Pearl River Estuary Chinese White Dolphin National Nature Reserve and its adjacent waters (NNR)) of Pearl River Estuary (PRE) were analyzed and compared by statistical simulation. It was found that TSS concentrations in east and west shoals were about 23mg/L and 64mg/L higher than that of the middle shoal, respectively. There was a significant decreasing trend of TSS concentration from the northwest (223.7mg/L) to southeast (51.4mg/L) of study area, with an average reduction of 5.86mg/Lperkm, which mainly attributes to unique interaction of runoff and tide in PRE. In high flow season, there existed a significant and definite annual cycle period (5-8years) of TSS concentration change primarily responding to the periodic variation of precipitation. There were five full-fledged period changes of TSS detected in west shoal and west channel (the years of changes in 1988, 1994, 1998, 2003, 2010, 2015), while there were the last four cycle periods found in middle shoal, east channel, east shoal and NNR only. TSS concentrations in shoals and channels of PRE showed a significant decreased trend mainly due to the dam construction at the same time, with an average annual TSS concentration decrease of 5.7-10.1mg/L in high flow season from 1988 to 2015. There was no significant change trend of TSS concentration in NNR before 2003, but the TSS concentration decreased significantly after the establishment of the NNR since June 2003, with an average annual decrease of 9.7mg/L from 2004 to 2015. It was deduced that man-made protection measures had a great influence

  13. Radioactivity of some specific underground workplaces in Hungary

    International Nuclear Information System (INIS)

    Szerbin, P.

    1998-01-01

    In this study, radon and radon daughter concentrations were measured in specific underground workplaces: in vine cellars, showcaves and caves for speleotherapeutic treatment of patients. These workplaces are considered to be affected by high radon concentrations, the workers in some cases can be exposed to radiation from radon and short-lived daughters at levels, comparable to those of other underground workplaces such as uranium mines. The aim of the study was to reveal the variation of the radon and radon progeny concentration, and to estimate the dose to the workers and visitors of these workplaces from the radon daughters. Seasonal variations of radon concentrations have been found in most of the caves investigated. The magnitude of the variation depends on the degree of isolation of the cave cavity from the outdoor atmosphere. The radon concentrations of the vine cellars were much lower than that of the caves. Because of the produced carbon dioxide gas in the process of sugar fermentation even the very old cellars are constructed well ventilated, consequently radon can not be accumulated in this underground cavities. From the measured radon and progeny concentrations cumulative potential alpha energy exposure, bronchial dose, and effective dose values were calculated for the staff, patients and visitors. The effective dose values for the cave personnel do not exceed the 10 mSv year -1 upper bound of the action level recommended for workplaces and even much lower for workers of cellars. The doses for visitors and patients were one or two magnitudes lower than that of the workers. (author)

  14. A vegetation control on seasonal variations in global atmospheric mercury concentrations

    Science.gov (United States)

    Jiskra, Martin; Sonke, Jeroen E.; Obrist, Daniel; Bieser, Johannes; Ebinghaus, Ralf; Myhre, Cathrine Lund; Pfaffhuber, Katrine Aspmo; Wängberg, Ingvar; Kyllönen, Katriina; Worthy, Doug; Martin, Lynwill G.; Labuschagne, Casper; Mkololo, Thumeka; Ramonet, Michel; Magand, Olivier; Dommergue, Aurélien

    2018-04-01

    Anthropogenic mercury emissions are transported through the atmosphere as gaseous elemental mercury (Hg(0)) before they are deposited to Earth's surface. Strong seasonality in atmospheric Hg(0) concentrations in the Northern Hemisphere has been explained by two factors: anthropogenic Hg(0) emissions are thought to peak in winter due to higher energy consumption, and atmospheric oxidation rates of Hg(0) are faster in summer. Oxidation-driven Hg(0) seasonality should be equally pronounced in the Southern Hemisphere, which is inconsistent with observations of constant year-round Hg(0) levels. Here, we assess the role of Hg(0) uptake by vegetation as an alternative mechanism for driving Hg(0) seasonality. We find that at terrestrial sites in the Northern Hemisphere, Hg(0) co-varies with CO2, which is known to exhibit a minimum in summer when CO2 is assimilated by vegetation. The amplitude of seasonal oscillations in the atmospheric Hg(0) concentration increases with latitude and is larger at inland terrestrial sites than coastal sites. Using satellite data, we find that the photosynthetic activity of vegetation correlates with Hg(0) levels at individual sites and across continents. We suggest that terrestrial vegetation acts as a global Hg(0) pump, which can contribute to seasonal variations of atmospheric Hg(0), and that decreasing Hg(0) levels in the Northern Hemisphere over the past 20 years can be partly attributed to increased terrestrial net primary production.

  15. Evaluation of between-cow variation in milk urea and rumen ammonia nitrogen concentrations and the association with nitrogen utilization and diet digestibility in lactating cows.

    Science.gov (United States)

    Huhtanen, P; Cabezas-Garcia, E H; Krizsan, S J; Shingfield, K J

    2015-05-01

    Concentrations of milk urea N (MUN) are influenced by dietary crude protein concentration and intake and could therefore be used as a biomarker of the efficiency of N utilization for milk production (milk N/N intake; MNE) in lactating cows. In the present investigation, data from milk-production trials (production data set; n=1,804 cow/period observations from 21 change-over studies) and metabolic studies involving measurements of nutrient flow at the omasum in lactating cows (flow data set; n=450 cow/period observations from 29 studies) were used to evaluate the influence of between-cow variation on the relationship of MUN with MNE, urinary N (UN) output, and diet digestibility. All measurements were made on cows fed diets based on grass silage supplemented with a range of protein supplements. Data were analyzed by mixed-model regression analysis with diet within experiment and period within experiment as random effects, allowing the effect of diet and period to be excluded. Between-cow coefficient of variation in MUN concentration and MNE was 0.13 and 0.07 in the production data set and 0.11 and 0.08 in the flow data set, respectively. Based on residual variance, the best model for predicting MNE developed from the production data set was MNE (g/kg)=238 + 7.0 × milk yield (MY; kg/d) - 0.064 × MY(2) - 2.7 × MUN (mg/dL) - 0.10 body weight (kg). For the flow data set, including both MUN and rumen ammonia N concentration with MY in the model accounted for more variation in MNE than when either term was used with MY alone. The best model for predicting UN excretion developed from the production data set (n=443) was UN (g/d)=-29 + 4.3 × dry matter intake (kg/d) + 4.3 × MUN + 0.14 × body weight. Between-cow variation had a smaller influence on the association of MUN with MNE and UN output than published estimates of these relationships based on treatment means, in which differences in MUN generally arise from variation in dietary crude protein concentration. For

  16. Genetic consequences of irradiation of one or both parents (results of experiments on Wistar rats). Exitus Lethalis in Wistar rats progeny after irradiation of one or both parents

    International Nuclear Information System (INIS)

    Nefedov, I.Yu.; Nefedova, I.Yu.; Palyga, G.F.

    2001-01-01

    Using offsprings of Wistar rats the quantitative regulations in their death in ontogenesis following irradiation of one or both parents at 0.25-4 Gy doses, the sex cells of which were at stages of mature oocytes and spermatozoa. are investigated. It is determined that the progeny death depends on the value of radiation dose to gametes of parents and takes place mainly in embryogenesis. Progeny of both exposed parents may have an increase in death as compared to that for one parent exposed. Phenomenon of progeny death increase resulted from the fertilization of both parents exposed to radiation is observed at the low doses and is absent at high radiation doses [ru

  17. Radon parameters in outdoor air

    International Nuclear Information System (INIS)

    Porstendoerfer, J.; Zock, Ch.; Wendt, J.; Reineking, A.

    2002-01-01

    For dose estimation by inhalation of the short lived radon progeny in outdoor air, the equilibrium factor (F), the unattached fraction (f p ), and the activity size distribution of the radon progeny were measured. Besides the radon parameter the meteorological parameter like temperature, wind speed, and rainfall intensity were registered. The measurements were carried out continuously for several weeks to find out the variation with time (day/night) and for different weather conditions. The radon gas, the unattached and aerosol-attached radon progenies were measured with an monitor developed for continuous measurements in outdoor air with low activity concentrations. For the determination of the activity size distribution a low pressure online alpha cascade impactor was used. The measured values of the equilibrium factor varied between 0.5-0.8 depending on weather conditions and time of the day. For high pressure weather conditions a diurnal variation of the F-factor was obtained. A lower average value (F=0.25) was registered during rainy days. The obtained f p -values varied between 0.04 and 0.12. They were higher than expected. The measured activity size distribution of the radon progeny averaged over a measurement period of three weeks can be approximated by a sum of three log-normal distributions. The greatest activity fraction is adsorbed on aerosol particles in the accumulation size range (100-1000 nm) with activity median diameters and geometric standard deviation values between 250-450 nm and 1.5-3.0, respectively. The activity median diameter of this accumulation mode in outdoor air was significantly greater than in indoor air (150-250 nm). An influence of the weather conditions on the activity of the accumulation particles was not significant. In contrast to the results of measurements in houses a small but significant fraction of the radon progeny (average value: 2%) is attached on coarse particles (>1000 nm). This fraction varied between 0-10%. 20

  18. Intein-mediated Cre protein assembly for transgene excision in hybrid progeny of transgenic Arabidopsis.

    Science.gov (United States)

    Ge, Jia; Wang, Lijun; Yang, Chen; Ran, Lingyu; Wen, Mengling; Fu, Xianan; Fan, Di; Luo, Keming

    2016-10-01

    An approach for restoring recombination activity of complementation split-Cre was developed to excise the transgene in hybrid progeny of GM crops. Growing concerns about the biosafety of genetically modified (GM) crops has currently become a limited factor affecting the public acceptance. Several approaches have been developed to generate selectable-marker-gene-free GM crops. However, no strategy was reported to be broadly applicable to hybrid crops. Previous studies have demonstrated that complementation split-Cre recombinase restored recombination activity in transgenic plants. In this study, we found that split-Cre mediated by split-intein Synechocystis sp. DnaE had high recombination efficiency when Cre recombinase was split at Asp232/Asp233 (866 bp). Furthermore, we constructed two plant expression vectors, pCA-NCre-In and pCA-Ic-CCre, containing NCre866-In and Ic-CCre866 fragments, respectively. After transformation, parent lines of transgenic Arabidopsis with one single copy were generated and used for hybridization. The results of GUS staining demonstrated that the recombination activity of split-Cre could be reassembled in these hybrid progeny of transgenic plants through hybridization and the foreign genes flanked by two loxP sites were efficiently excised. Our strategy may provide an effective approach for generating the next generation of GM hybrid crops without biosafety concerns.

  19. Radon in air concentrations arising from storage of articles containing radium or thorium

    International Nuclear Information System (INIS)

    Slater, M.; Gooding, M.

    2006-01-01

    A major component of public and occupational radiation exposure worldwide arises from the inhalation of radon and thoron gases, produced during the decay of naturally occurring uranium and thorium respectively. Whilst radon and thoron exposures are normally associated with the natural environment, there may also be a risk associated with sources, manufactured articles and waste produced through refining and concentration of naturally occurring radioactive material. Sources and articles manufactured from refined uranium do not normally give rise to the release of radon as the uranium progeny are largely removed during production and, if removed, will take thousands of years to reach full equilibrium with the uranium parent isotopes. Exposure to radon -222 ( 222 Rn) may, however, arise in areas where the uranium-238 ( 238 U) daughter radium-226 ( 226 Ra) is concentrated, for example in the form of sources, luminous articles or low-specific activity (LSA) scale. Exposure to radon- 220 ( 220 Rn), otherwise known as thoron, may occur in areas where thorium isotopes are concentrated, for example as manufactured laboratory thorium compounds. This paper explores the issues affecting radon and thoron release from manufactured articles containing uranium and thorium and their progeny. A methodology is provided for the calculation of 222 Rn and 220 Rn in air concentrations likely to arise as a result of the storage and use of articles containing radium-226 ( 226 Ra) or thorium-232 ( 232 Th). The methodology provided in the document allows derivation of the equilibrium equivalent radon concentration and the radon exposure rate in circumstances where the ventilation rate and volume of the facility can be reliably estimated and the quantities of 226 Ra or 232 Th held are known. A critical variable in the calculation is the release fraction (i.e. the proportion of radon generated that is release to atmosphere), and this paper considers methods for estimating this parameter

  20. Broiler performance, hatching egg, and age relationships of progeny from standard and dwarf broiler dams.

    Science.gov (United States)

    Tahir, M; Cervantes, H; Farmer, C W; Shim, M Y; Pesti, G M

    2011-06-01

    The relationship of egg and chick weights to the performance of broiler chickens from two 42-wk-old flocks (standard and dwarf dams) having male parents from the same genetic stock was investigated in this study. Fertility (91.7 vs. 94.7%) and hatchability (95.2 vs. 96.3%) were not significantly (P > 0.10) different for eggs from standard and dwarf dams, respectively. Egg weight contributed significantly to the variation in BW [BW = β(0) + β(i) (egg weight) + β(i) (dam) + β(i) (sex)]. Body weight as a function of chick weight was not significant. However, chick weight was significant when included in a model with egg weight, suggesting that significant differences in BW at 50 d could be attributed to both egg and chick weights. The negative coefficient for chick weight indicated that between the 2 broilers of the same egg weight, the one with the greater chick weight would have the smaller 50-d BW. Chick weight was a linear function of egg weight. Similarly, the effect of egg or chick weight on broiler BW at 35 or 50 d was best represented by a single linear function. Dam genotype did not contribute significantly to variation in 50-d BW after variation attributable to egg weight was removed from the model. Differences in BW attributable to egg weight increased with broiler age. The coefficients of egg weight and chick weight showed that the differences in BW per gram of egg were 1.43, 3.06, 6.24, and 7.61 g and those per gram of chick were 1.87, 3.99, 8.14, and 9.93 g, respectively, at 7, 21, 35, and 50 d. Body weight increased by 0.1563 times egg weight (and 0.2092 times chick weight) with each additional day of age for both sexes and genotypes. Clearly, both egg and chick weights are important for modeling or predicting market-age broiler BW and economic returns. The relatively small relationship between BW and egg weight demonstrates that genetic selection over the past 3 decades has decreased the influence of egg weight on broiler growth. The present dwarf

  1. Radon, thoron and their progeny levels in some dwellings of Union Territory Chandigarh, India using SSNTDs

    International Nuclear Information System (INIS)

    Mehta, Vimal; Kumar, Amit; Chauhan, R.P.; Mudahar, G.S.

    2013-01-01

    Indoor air quality is an important issue for protection against adverse health effects caused by the inhalation of pollutants because most individuals spend 90% of their time indoors and that indoor air quality is deteriorated by a large variety of sources. Out of these sources radon is a major pollutant and is an important global problem of radiation hygiene. Radon and its progeny are the major contributors in the radiation dose received by general population of the world. Next to cigarette smoking, the inhalation of radon gas and the products of its radioactive disintegration are considered the most significant cause of lung cancer. Due to the potentially serious public health implications of exposure to high levels of radon, the environmental monitoring of radon, thoron and their progeny in some dwellings of Chandigarh, union territory of India has been carried out. The radon-thoron twin dosimeter cups were used for the study. The aim of the study is the possible health risk assessment in the dwellings under consideration. (author)

  2. Serum uric acid concentrations and SLC2A9 genetic variation in Hispanic children: The Viva La Familia Study

    Science.gov (United States)

    Elevated concentrations of serum uric acid are associated with increased risk of gout and renal and cardiovascular diseases. Genetic studies in adults have consistently identified associations of solute carrier family 2, member 9 (SLC2A9), polymorphisms with variation in serum uric acid. However, it...

  3. Trophic calculations reveal the mechanism of population-level variation in mercury concentrations between marine ecosystems: Case studies of two polar seabirds

    International Nuclear Information System (INIS)

    Brasso, Rebecka L.; Polito, Michael J.

    2013-01-01

    Highlights: • Ecosystem-specific baseline and consumer δ 15 N paired for population-specific trophic level. • Source of population-level variation in mercury exposure identified in two seabirds. • High mercury and trophic position suggests trophic driver of population-level variation. • Trophic similarities, differing mercury reveals geographic differences in bioavailability. -- Abstract: The incorporation of quantitative trophic level analysis in ecotoxicological studies provides explanatory power to identify the factors, trophic or environmental, driving population-level variation in mercury exposure at large geographic scales. In the Antarctic marine ecosystem, mercury concentrations and stable isotope values in Adélie penguins (Pygoscelis adeliae) were compared between the Antarctic Peninsula and the Ross Sea. Correcting tissue δ 15 N values for baseline δ 15 N values revealed population-level differences in trophic position which contributes to differences in mercury. Data from Thick-billed murres (Uria lomvia) were synthesized from published values from Baffin Bay and Svalbard to demonstrate the utility of baseline δ 15 N values in identifying differences in environmental mercury exposure independent of diet. Here, we demonstrate the importance of calculating population-specific trophic level data to uncover the source of variation in mercury concentrations between geographically distinct populations of marine predators

  4. Identification of cocoa trees combining high yield potential and resistance to diseases in segregating progenies In Ecuador

    Science.gov (United States)

    Diseases and low yielding planting material are the main factors limiting production of “fine” or “flavour” cocoa in Ecuador. This makes it necessary to develop modern varieties capable of overcoming these limitations. During the 1960s and 1970s INIAP tested several progenies from selected crosses...

  5. Differential gene expression of wheat progeny with contrasting levels of transpiration efficiency.

    Science.gov (United States)

    Xue, Gang-Ping; McIntyre, C Lynne; Chapman, Scott; Bower, Neil I; Way, Heather; Reverter, Antonio; Clarke, Bryan; Shorter, Ray

    2006-08-01

    High water use efficiency or transpiration efficiency (TE) in wheat is a desirable physiological trait for increasing grain yield under water-limited environments. The identification of genes associated with this trait would facilitate the selection for genotypes with higher TE using molecular markers. We performed an expression profiling (microarray) analysis of approximately 16,000 unique wheat ESTs to identify genes that were differentially expressed between wheat progeny lines with contrasting TE levels from a cross between Quarrion (high TE) and Genaro 81 (low TE). We also conducted a second microarray analysis to identify genes responsive to drought stress in wheat leaves. Ninety-three genes that were differentially expressed between high and low TE progeny lines were identified. One fifth of these genes were markedly responsive to drought stress. Several potential growth-related regulatory genes, which were down-regulated by drought, were expressed at a higher level in the high TE lines than the low TE lines and are potentially associated with a biomass production component of the Quarrion-derived high TE trait. Eighteen of the TE differentially expressed genes were further analysed using quantitative RT-PCR on a separate set of plant samples from those used for microarray analysis. The expression levels of 11 of the 18 genes were positively correlated with the high TE trait, measured as carbon isotope discrimination (Delta(13)C). These data indicate that some of these TE differentially expressed genes are candidates for investigating processes that underlie the high TE trait or for use as expression quantitative trait loci (eQTLs) for TE.

  6. Determination of the variation of mercury isotope concentration based on spectral-phase effects

    International Nuclear Information System (INIS)

    Ganeev, A.A.; Man', D.D.; Turkin, Yu.I.

    1988-01-01

    A method of isotopic atomic-absorption analysis, based on spectral-phase effects in which there is no need to use several sources of radiation with pure isotopes of the analyte element, was developed. The method made it possible to simplify the analysis and to determine the variation of the concentration of mercury isotopes from one deposit to another with an accuracy several times higher that of traditional methods of spectral isotopic analysis. The method was tested on mercury 198 and mercury 202. The isotopic analyzer is diagramed and described. The mechanism of spectral-phase effects was determined by the difference in effective photon lifetimes, corresponding to different components of the hyperfine structure of the resonance line of mercury at 254 nm

  7. Variation of NO2 and NOx concentrations between and within 36 European study areas: Results from the ESCAPE study

    NARCIS (Netherlands)

    Cyrys, J.; Eeftens, M.R.|info:eu-repo/dai/nl/315028300; Heinrich, J.; Ampe, C.; Armengaud, A.; Beelen, R.; Bellander, T.; Beregszaszi, T.; Birk, M.; Cesaroni, G.; Cirach, M.; de Hoogh, K.; de Nazelle, A.; de Vocht, F.; Declercq, C.; Dėdelė, A.; Dimakopoulou, K.; Eriksen, K.; Galassi, C.; Grąulevičienė, R.; Grivas, G.; Gruzieva, O.; Gustafsson, A.H.; Hoffmann, B.; Iakovides, M.; Ineichen, A.; Krämer, U.; Lanki, T.; Lozano, P.; Madsen, C.; Meliefste, K.; Modig, L.; Mölter, A.; Mosler, G.; Nieuwenhuijsen, M.; Nonnemacher, M.; Oldenwening, M.; Peters, A.; Pontet, S.; Probst-Hensch, N.; Quass, U.; Raaschou-Nielsen, O.; Ranzi, A.; Sugiri, D.; Stephanou, E.G.; Taimisto, P.; Tsai, M-Y.; Vaskövi, É.; Villani, S.; Wang, M.|info:eu-repo/dai/nl/345480279; Brunekreef, B.|info:eu-repo/dai/nl/067548180; Hoek, G.|info:eu-repo/dai/nl/069553475

    2012-01-01

    The ESCAPE study (European Study of Cohorts for Air Pollution Effects) investigates long-term effects of exposure to air pollution on human health in Europe. This paper documents the spatial variation of measured NO2 and NOx concentrations between and within 36 ESCAPE study areas across Europe. In

  8. Effects of feeding ground redberry juniper (Juniperus pinchotii) to gestating ewes on pre- and postpartum performance, serum metabolites and hormones, milk fatty acid composition, and progeny preweaning performance.

    Science.gov (United States)

    Stewart, W C; Whitney, T R; Scholljegerdes, E J; Hallford, D M; Walker, J W; Adams, R P; Naumann, H D

    2017-09-01

    The objective of this research was to evaluate effects of replacing sorghum × Sudangrass hay with ground juniper in gestating ewe supplements on pre- and postpartum growth performance, serum metabolites and hormonal concentrations, milk fatty acid composition, and progeny preweaning performance. In a completely randomized design, commercial Rambouillet ewes (age = 3 to 5 yr; initial BW = 65.2 ± 1.6 kg) on a base diet of long-stem sorghum × Sudangrass hay were assigned to 1 of 4 dietary supplements in which ground juniper replaced 0% (CNTL), 33% (18JUN), 66% (36JUN), or 100% (54JUN) of the ground sorghum × Sudangrass hay in a pelleted supplement with ground juniper from d 38 ± 4 of gestation to 2 d postpartum. Treatment DM diet intake overall (g/kg BW) in ewes receiving no juniper was similar ( ≥ 0.38) to that of those receiving increasing concentrations of juniper. Changes in ewe BW and BCS were similar ( ≥ 0.24) in ewes throughout gestation. All serum metabolites and hormones were within normal clinical ranges; however, serum IGF-1 decreased linearly ( = 0.003), alanine increased (linear; = 0.003), and serum Na decreased (linear; = 0.049) as the percentage of juniper increased in the diet. Ewe milk fatty acid composition was similar ( > 0.05) for the majority of fatty acids across treatment groups, with the exception of arachidonic acid (C20:4n6) being greater ( hormones measured pre- and postpartum. Lamb birth weight and preweaning performance appeared unaffected by maternal consumption of ground juniper containing supplements. Results also provide novel information regarding the effects of plant secondary compound consumption throughout pregnancy on ewe and progeny performance and health.

  9. Silencing of a putative immunophilin gene in the cattle tick Rhipicephalus (Boophilus microplus increases the infection rate of Babesia bovis in larval progeny

    Directory of Open Access Journals (Sweden)

    Knowles Donald P

    2009-11-01

    Full Text Available Abstract Background The cattle tick Rhipicephalus (Boophilus microplus is involved in the transmission of the protozoan Babesia bovis, the etiological agent of bovine babesiosis. Interactions between ticks and protozoa are poorly understood and the investigation of tick genes that affect tick fitness and protozoan infection can set the stage for dissecting the molecular interactions between the two species. Results In this study, RNA interference was used to silence R. microplus genes that had been previously shown to be up-regulated in response to B. bovis infection. The silencing of a putative immunophilin gene (Imnp in female ticks fed on a calf acutely infected with B. bovis decreased the hatching rate and survival of larval progeny. Interestingly, Imnp was up-regulated significantly in ovaries of R. microplus in response to B. bovis infection and its silencing in female ticks significantly increased the infection rate of the protozoan in larval progeny. The results also showed that the silencing of a putative Kunitz-type serine protease inhibitor (Spi gene and a putative lipocalin (Lpc gene decreased the fitness of R. microplus females, but had no significant effect on the infection rate of B. bovis in larval progeny. Conclusion The silencing of the Imnp, Spi or Lpc genes decreased the fitness of R. microplus females fed on a calf during acute B. bovis infection. The Imnp gene data suggest that this putative immunophilin gene is involved in the defense system of R. microplus against B. bovis and may play a role in controlling the protozoan infection in tick ovaries and larval progeny.

  10. Probing the application of Fourier Transform Infrared (FTIR) spectroscopy for assessment of deposited flux of Radon and Thoron progeny in high exposure conditions

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, R., E-mail: rosaline@barc.gov.in; Sapra, B.K.; Rout, R.P.; Prajith, R.

    2016-12-01

    Direct measurement of Radon and Thoron progeny in the atmosphere and occupational environments such as Uranium mines, Uranium and Thorium handling facilities has gained importance because of its radiological significance in inhalation dose assessment. In this regard, Radon and Thoron Progeny sensors (DTPS and DRPS) are the only passive solid state nuclear track detector (SSNTD, LR115) based devices which are being extensively used for time integrated direct progeny measurements. An essential component of the analysis is the chemical etching of the detectors, followed by spark counting of tracks and then estimation of the inhalation dose using appropriate calibration factors. Alternatively, the tracks may be counted using image analysis techniques. However, under high exposure conditions, both these methods have inherent limitations and errors arising due to increased frequency of tracks. In the present work, we probe the use of Fourier Transform Infra Red (FTIR) spectroscopy to analyse the deposited fluence of the progeny particulates based on change in transmittance of the nitric group vibrational bands of the LR115. A linear relationship between the transmittance and the deposited fluence was observed, which can be used to estimate the deposited fluence rate and the inhalation dose. This alternative method of analysis will provide a faster and non-destructive technique for inhalation dose assessment, specially for routine large scale measurements. - Highlights: • An alternative method of inhalation dose assessment. • Linearity between the transmittance of nitric goup bands and the deposited fluence. • Faster and non-destructive technique for high exposure scenarios.

  11. Variation of haemoglobin extinction coefficients can cause errors in the determination of haemoglobin concentration measured by near-infrared spectroscopy

    International Nuclear Information System (INIS)

    Kim, J G; Liu, H

    2007-01-01

    Near-infrared spectroscopy or imaging has been extensively applied to various biomedical applications since it can detect the concentrations of oxyhaemoglobin (HbO 2 ), deoxyhaemoglobin (Hb) and total haemoglobin (Hb total ) from deep tissues. To quantify concentrations of these haemoglobin derivatives, the extinction coefficient values of HbO 2 and Hb have to be employed. However, it was not well recognized among researchers that small differences in extinction coefficients could cause significant errors in quantifying the concentrations of haemoglobin derivatives. In this study, we derived equations to estimate errors of haemoglobin derivatives caused by the variation of haemoglobin extinction coefficients. To prove our error analysis, we performed experiments using liquid-tissue phantoms containing 1% Intralipid in a phosphate-buffered saline solution. The gas intervention of pure oxygen was given in the solution to examine the oxygenation changes in the phantom, and 3 mL of human blood was added twice to show the changes in [Hb total ]. The error calculation has shown that even a small variation (0.01 cm -1 mM -1 ) in extinction coefficients can produce appreciable relative errors in quantification of Δ[HbO 2 ], Δ[Hb] and Δ[Hb total ]. We have also observed that the error of Δ[Hb total ] is not always larger than those of Δ[HbO 2 ] and Δ[Hb]. This study concludes that we need to be aware of any variation in haemoglobin extinction coefficients, which could result from changes in temperature, and to utilize corresponding animal's haemoglobin extinction coefficients for the animal experiments, in order to obtain more accurate values of Δ[HbO 2 ], Δ[Hb] and Δ[Hb total ] from in vivo tissue measurements

  12. Variation of haemoglobin extinction coefficients can cause errors in the determination of haemoglobin concentration measured by near-infrared spectroscopy

    Science.gov (United States)

    Kim, J. G.; Liu, H.

    2007-10-01

    Near-infrared spectroscopy or imaging has been extensively applied to various biomedical applications since it can detect the concentrations of oxyhaemoglobin (HbO2), deoxyhaemoglobin (Hb) and total haemoglobin (Hbtotal) from deep tissues. To quantify concentrations of these haemoglobin derivatives, the extinction coefficient values of HbO2 and Hb have to be employed. However, it was not well recognized among researchers that small differences in extinction coefficients could cause significant errors in quantifying the concentrations of haemoglobin derivatives. In this study, we derived equations to estimate errors of haemoglobin derivatives caused by the variation of haemoglobin extinction coefficients. To prove our error analysis, we performed experiments using liquid-tissue phantoms containing 1% Intralipid in a phosphate-buffered saline solution. The gas intervention of pure oxygen was given in the solution to examine the oxygenation changes in the phantom, and 3 mL of human blood was added twice to show the changes in [Hbtotal]. The error calculation has shown that even a small variation (0.01 cm-1 mM-1) in extinction coefficients can produce appreciable relative errors in quantification of Δ[HbO2], Δ[Hb] and Δ[Hbtotal]. We have also observed that the error of Δ[Hbtotal] is not always larger than those of Δ[HbO2] and Δ[Hb]. This study concludes that we need to be aware of any variation in haemoglobin extinction coefficients, which could result from changes in temperature, and to utilize corresponding animal's haemoglobin extinction coefficients for the animal experiments, in order to obtain more accurate values of Δ[HbO2], Δ[Hb] and Δ[Hbtotal] from in vivo tissue measurements.

  13. The Influence of Variation in Time and HCl Concentration to the Glucose Produced from Kepok Banana

    Science.gov (United States)

    Widodo M, Rohman; Noviyanto, Denny; RM, Faisal

    2016-01-01

    Kepok banana (Musa paradisiaca) is a plant that has many advantagesfrom its fruit, stems, leaves, flowers and cob. However, we just tend to take benefit from the fruit. We grow and harvest the fruit without taking advantages from other parts. So they would be a waste or detrimental to animal nest if not used. The idea to take the benefit from the banana crop yields, especially cob is rarely explored. This study is an introduction to the use of banana weevil especially from the glucose it contains. This study uses current methods of hydrolysis using HCl as a catalyst with the concentration variation of 0.4 N, 0.6 N and 0.8 N and hydrolysis times variation of 20 minutes, 25 minutes and 30 minutes. The stages in the hydrolysis include preparation of materials, the process of hydrolysis and analysis of test results using Fehling and titrate with standard glucose solution. HCl is used as a catalyst because it is cheaper than the enzyme that has the same function. NaOH 60% is used for neutralizing the pH of the filtrate result of hydrolysis. From the results of analysis, known thatthe biggest yield of glucose is at concentration 0.8 N and at 30 minutes reaction, it contains 6.25 gram glucose / 20 gram dry sampel, and the convertion is 27.22% at 20 gram dry sampel.

  14. Intraspecific variation in {sup 137}Cs activity concentration in sporocarps of Suillus variegatus in seven Swedish populations

    Energy Technology Data Exchange (ETDEWEB)

    Dahlberg, Anders [Swedish Univ. of Agricultural Sciences, Forest Mycology and Pathology Dept., Uppsala (Sweden); Nikolova, Ivanka; Johanson, K.-J. [Swedish Univ. of Agricultural Sciences, Radioecology Dept., Uppsala (Sweden)

    1997-05-01

    Following the Chernobyl accident in 1986, sporocarps of Suillus variegatus in Sweden showed a large amount of individual variation in concentration of {sup 137}Cs activity. Our aim was to determine the degrees to which this variability in sporocarp {sup 137}Cs levels could be explained by differences between (i) local populations, (ii) fungal genets and (iii) locations within genets. Five populations in a 100-yr-old Scots pine forest, located within a 1 km{sup 2} area, and two populations in Scots pine/Norway spruce forest, located 40 km north-west of Uppsala, were investigated. In total, 154 sporocarps were analysed to determine their {sup 137}Cs content. Of these, the genetic affiliations of 86 were successfully characterized using somatic incompatibility reactions. Twenty-six genets were found which, on average, consisted of 6.5 sporocarps. The genets averaged 7.5 m in size, measured as the length between the most distant sporocarps. The mean sporocarp {sup 137}Cs level was 67.1 {+-} 2.8 kBq kgsup(-1) D.W. (range between 13.6 and 182). According to analyses of variance, within-population variation accounted for 60% of the total variation in {sup 137}Cs levels, while 40% was ascribed to variation among populations. Within a population, {sup 137}Cs levels did not generally differ significantly between genets. Plausible reasons for intraspecific variation in radiocaesium content in sporocarps are discussed. (author).

  15. VARIABILIDAD GENÉTICA DEL CRECIMIENTO EN PROGENIES SELECTAS DE Pinus radiata

    Directory of Open Access Journals (Sweden)

    Freddy Mora

    2006-09-01

    Full Text Available Heredabilidad en sentido estricto (h2, correlación genética intra-clase (2IC y componentes de varianza para la altura, diámetro a la altura del pecho (DAP y volumen del fuste, a los siete años de edad después de la plantación, fueron analizados en dos ensayos de progenie de Pinus radiata establecidos en el sur de Chile, en orden a examinar la variabilidad genética del crecimiento en una generación avanzada de la especie. Estos ensayos incluyeron árboles provenientes de propagación vegetativa y generativa. Las heredabilidades fueron estimadas para los árboles originados de semillas, y mostraron los siguientes valores: altura, 0.08-0.13; diámetro a la altura del pecho, 0-0.13; volumen del fuste, 0-0.09. Los valores de la correlación genética intra-clase, estimados para el grupo de árboles originados de propagación vegetativa, fueron moderados a bajos (2IC: altura, 0.1-0.11; diámetro a la altura del pecho, 0.01-0.05; volumen del fuste, 0.03-0.06. No obstante la presencia de heredabilidades y correlaciones moderadas para algunas características y, la variación relativamente limitada entre grupos de árboles reflejan la fuerte selección realizada a las progenies. En general, los árboles provenientes de estacas presentaron una tendencia a la menor variación intra-genotípica, y evidenciaron magnitudes relativas de las varianzas debida al grupo (2G mayores a las varianzas familiares (2F, en cuatro de seis caracteres evaluados, indicando una tendencia a la mayor homogeneidad en el crecimiento, característica común de la propagación vegetativa.

  16. A study on variation in dissolved silica concentration in groundwater of hard rock aquifers in Southeast coast of India

    International Nuclear Information System (INIS)

    Pradeep, K; Nepolian, M; Anandhan, P; Chandran; Kaviyarasan, R; Chidambaram, S; Prasanna, M V

    2016-01-01

    Ground water of hard rock aquifers due to its lesser permeability results in the increased residence time, which leads to the higher concentration of ions. Hence in order to understand the hydro-geochemistry of the groundwater of a hard rock aquifer in India, 23 groundwater samples were collected from different locations of the study area and subjected to analysis of major cations and anions. The results of silica showed different range of concentration and was plotted in different groups. In order to understand the reason for this variation, different techniques like Thermodynamics, Statistics and GIS were adopted and it was inferred that the concentration was mainly governed by lithology and land use pattern of the study area. (paper)

  17. Influencia del estrés térmico en la calidad panadera del trigo: progenies con diferentes niveles de sensibilidad Effects of heat stress on breadmaking quality of wheat: progenies with different levels of sensitivity

    Directory of Open Access Journals (Sweden)

    Z. A. Gaido

    2008-12-01

    Full Text Available Picos de altas temperaturas durante el llenado del grano de trigo están relacionados con modificaciones de la calidad panadera, especialmente con disminuciones en la fuerza de la masa. Se evaluó la influencia del estrés térmico en la calidad de progenies de trigo pan clasificándolas en grupos según su sensibilidad. Se analizaron 60 progenies de trigo durante 3 años consecutivos. Se tomaron fechas de siembra, espigazón, cosecha y temperaturas máximas diarias. Se determinó, para cada muestra, la variable estrés térmico total (ETT, definida como la sumatoria de grados de los episodios de estrés térmico (al menos 2 días consecutivos con temperaturas > 30 ºC durante el periodo del llenado efectivo del grano, estableciéndose 3 niveles: bajo, medio y alto. Se midieron proteína en grano (PTG, gluten húmedo (GH y variables mixográficas. Se realizaron análisis de la varianza y coeficientes de correlación de Pearson. Para niveles de ETT medio y alto disminuyeron PTG, GH y altura mixográfica (Amix, mientras que la fuerza de la masa medida en tiempo de desarrollo mixográfico (TDmix disminuyó sólo en 62% de las muestras. En este sentido, se identificaron genotipos que poseen tolerancia al estrés térmico y una mayor estabilidad de la masa.Periods of heat stress during the grain filling have been observed to influence the baking quality of wheat with a decline in dough strength. The objective of this study was to evaluate the effects of heat stress on bread-making quality of wheat and to identify progenies with different levels of sensitivity. Sixty wheat progenies were analyzed for three consecutive years. The dates of sowing, heading, harvests and the daily maximum temperatures were taken. For each sample, the total heat stress (ETT, defined as the cumulative number of degrees of the episodes of heat stress (at least two consecutive days with temperatures > 30 ºC happened during the grain filling period, was determined. Three

  18. The Progeny Test Half-Sib Paraserianthes falcataria L. Nielsen at Taman Hutan Blok Cikabayan

    Directory of Open Access Journals (Sweden)

    Ali Mukmin

    2012-09-01

    Full Text Available 800x600 Analysis of genetic parameters in seedling seed orchard progeny trial of Paraserianthes falcataria at Taman Hutan Blok Cikabayan are very important to decide to continue  the breeding program.  The analysis was coducted on estimation of individual heritability and genetic correlation between traits. Result of analysis shows that individual heritability for height, diameter and form traits.  Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4

  19. Use of chemical mutagen for induction of useful genetic variation in different oil seed rape (brassica napus L.) cultivars

    International Nuclear Information System (INIS)

    Ali, I.; Shah, S.A.; Shah, S.J.A.; Rehman, K.

    1995-01-01

    Pre soaked seeds for 16 hrs of oil seed Rape cvs. Tower and Wester were treated with 1-3% concentrations of ethylene methane sulphonate (EMS) for 4 hrs with the objective to generate variation in characters of importance such as, early maturity, semi dwarf stature, lodging resistance and different yield components. After post washing (4 hrs) the seeds were filter dried and planted directly in the field as M1. Selection for desirable mutants was carried out in M2 and a number of mutants with desirable traits were selected during 1990-91. The mutants were tested for stability of the selected traits in plant to progenies in M3/M4 during 1992 and 1993. The stable 17 mutants were evaluated for yield and other agronomic characters in M5, in preliminary yield trials, during 1993-94. Eleven mutants exhibited early maturity and high yield potential than parent and local commercial variety. The promising mutants will be further tested in yield trials in future for confirmation of results. (author)

  20. Diurnal variation of the serum leptin concentration in patients with anorexia nervosa

    DEFF Research Database (Denmark)

    Støving, R K; Vinten, J; Handberg, A

    1998-01-01

    , however, this has been reported to be absent in normal weighted amenorrheic athletes. Anorexia nervosa is associated with multiple endocrine abnormalities. Hypothalamic amenorrhoea often precedes the weight loss and may persist after weight recovery. We hypothesized that leptin could be involved...... in the regulation of eating behaviour and gonadal function in anorexia nervosa. DESIGN: We measured the concentration of leptin in serum samples taken after an overnight fast in 18 female anorexia nervosa patients and 11 controls. To study diurnal variation, eight patients and 11 controls were hospitalized for 24 h...... and had a standardized diet at regular times. Seven blood samples were obtained at 4 h intervals from each subject. PATIENTS: The patients fulfilled the DSM-IV criteria for anorexia nervosa. The mean body mass index for the patients was 14.2 +/- 2.3 kg/m2 and for controls 20.3 +/- 1.7 kg/m2. RESULTS...