Flow shear stabilization of hybrid electron-ion drift mode in tokamaks

International Nuclear Information System (INIS)

Bai, L.

2001-01-01

In this paper, a model of sheared flow stabilization on hybrid electron-ion drift mode is proposed. At first, in the presence of dissipative trapped electrons, there exists an intrinsic oscillation mode in tokamak plasmas, namely hybrid dissipative trapped electron-ion temperature gradient mode (hereafter, called as hybrid electron-ion drift mode). This conclusion is in agreement with the observations in the simulated tokamak experiment on the CLM. Then, it is found that the coupling between the sheared flows and dissipative trapped electrons is proposed as the stabilization mechanism of both toroidal sheared flow and poloidal sheared flow on the hybrid electron-ion drift mode, that is, similar to the stabilizing effect of poloidal sheared flow on edge plasmas in tokamaks, in the presence of both dissipative trapped electrons and toroidal sheared flow, large toroidal sheared flow is always a strong stabilizing effect on the hybrid electron-ion drift mode in internal transport barrier location, too. This result is consistent with the experimental observations in JT-60U. (author)

The Phenotypic Performances of Gerbera Local Bali X Rubby Red Hybrids

Directory of Open Access Journals (Sweden)

Kurnia Yuniarto

2018-02-01

Full Text Available Gerbera is one of important cut flowers in floriculture industries. It can substitute of chrysanthemum. The novelty of cultivar and superiority of characteristic of gerbera are necessary in the floriculture markets. New cultivars can be created through hybridization between cultivars. This study aimed to find out the phenotypic performances of gerbera hybrids of Local Bali x Rubby Red. The research was conducted in Indonesian Ornamental Crops Research Institute, West Java, Indonesia from January 2014 to September 2015. Eight progenies of F1 hybrids and their parents (Local Bali and Rubby Red were used as materials. In the hybridization process Local Bali and Rubby Red were used as female and male parents respectively. Genetic variabilities of Gerbera were achieved through this hybridization. Gerbera progeny no. 20.009 had the longest inflorescence diameter, the biggest outer sepal and the highest number of sepals compared to the others. The flower vase life of this progeny was not significantly difference to the male parent. Qualitative characters observation showed that the hybrids were classified into two groups based on flower type, four groups of outer ray florets and two-disc groups of petal color.

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.

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.

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.)

Strong electron dissipation by a mode converted ion hybrid (Bernstein) wave

International Nuclear Information System (INIS)

Lashmore-Davies, C.N.; Ram, A.K.

1996-01-01

The fast wave approximation, extended to include the effects of electron dissipation, is used to calculate the power mode converted to the ion hybrid (Bernstein) wave in the vicinity of the ion hybrid resonance. The power absorbed from the fast wave by ion cyclotron damping and by electron Landau and transit time damping (including cross terms) is also calculated. The fast wave equation is solved for either the Budden configuration of a cut-off-resonance pair or the triplet configuration of cut-off-resonance-cut-off. The fraction mode converted is compared for the triplet case and the Budden multi-pass situation. The electron damping rate of the ion hybrid wave is obtained from the local dispersion relation and a ray tracing code is used to calculate the damping of the mode converted ion hybrid wave by the electrons as it propagates away from the resonance. Quantitative results for a range of conditions relevant to JET, TFTR and ITER are given. copyright 1996 American Institute of Physics

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

Mapping the electrostatic potential of Au nanoparticles using hybrid electron holography

Energy Technology Data Exchange (ETDEWEB)

Ozsoy-Keskinbora, Cigdem, E-mail: c.ozsoy@fkf.mpg.de [Stuttgart Center for Electron Microscopy, Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart (Germany); Boothroyd, Chris B.; Dunin-Borkowski, Rafal E. [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich, 52425 Jülich (Germany); Aken, Peter A. van [Stuttgart Center for Electron Microscopy, Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart (Germany); Koch, Christoph T. [Structure Research & Electron Microscopy group, Department of Physics, Humboldt University of Berlin, Newtonstraße 15, 12489 Berlin (Germany)

2016-06-15

Electron holography is a powerful technique for characterizing electrostatic potentials, charge distributions, electric and magnetic fields, strain distributions and semiconductor dopant distributions with sub-nm spatial resolution. Mapping internal electrostatic and magnetic fields within nanoparticles and other low-dimensional materials by TEM requires both high spatial resolution and high phase sensitivity. Carrying out such an analysis fully quantitatively is even more challenging, since artefacts such as dynamical electron scattering may strongly affect the measurement. In-line electron holography, one of the variants of electron holography, features high phase sensitivity at high spatial frequencies, but suffers from inefficient phase recovery at low spatial frequencies. Off-axis electron holography, in contrast, can recover low spatial frequency phase information much more reliably, but is less effective in retrieving phase information at high spatial frequencies when compared to in-line holography. We investigate gold nanoparticles using hybrid electron holography at both atomic-resolution and intermediate magnification. Hybrid electron holography is a novel technique that synergistically combines off-axis and in-line electron holography, allowing the measurement of the complex wave function describing the scattered electrons with excellent signal-to-noise properties at both high and low spatial frequencies. The effect of dynamical electron scattering is minimized by beam tilt averaging. - Highlights: • Hybrid electron holography approach applied to Au nanoparticles. • Proof of principle of atomic resolution hybrid electron holography experiment demonstrated. • Dynamical scattering artifacts decrease by varying the illumination direction. • The effect of the number of iterations and noise on the low spatial frequencies in the phase are discussed.

Mapping the electrostatic potential of Au nanoparticles using hybrid electron holography

International Nuclear Information System (INIS)

Ozsoy-Keskinbora, Cigdem; Boothroyd, Chris B.; Dunin-Borkowski, Rafal E.; Aken, Peter A. van; Koch, Christoph T.

2016-01-01

Electron holography is a powerful technique for characterizing electrostatic potentials, charge distributions, electric and magnetic fields, strain distributions and semiconductor dopant distributions with sub-nm spatial resolution. Mapping internal electrostatic and magnetic fields within nanoparticles and other low-dimensional materials by TEM requires both high spatial resolution and high phase sensitivity. Carrying out such an analysis fully quantitatively is even more challenging, since artefacts such as dynamical electron scattering may strongly affect the measurement. In-line electron holography, one of the variants of electron holography, features high phase sensitivity at high spatial frequencies, but suffers from inefficient phase recovery at low spatial frequencies. Off-axis electron holography, in contrast, can recover low spatial frequency phase information much more reliably, but is less effective in retrieving phase information at high spatial frequencies when compared to in-line holography. We investigate gold nanoparticles using hybrid electron holography at both atomic-resolution and intermediate magnification. Hybrid electron holography is a novel technique that synergistically combines off-axis and in-line electron holography, allowing the measurement of the complex wave function describing the scattered electrons with excellent signal-to-noise properties at both high and low spatial frequencies. The effect of dynamical electron scattering is minimized by beam tilt averaging. - Highlights: • Hybrid electron holography approach applied to Au nanoparticles. • Proof of principle of atomic resolution hybrid electron holography experiment demonstrated. • Dynamical scattering artifacts decrease by varying the illumination direction. • The effect of the number of iterations and noise on the low spatial frequencies in the phase are discussed.

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)

Genetic parameters of pure and hybrid populations of Eucalyptus ...

African Journals Online (AJOL)

In order to review Sappi Forests' breeding strategy for E. urophylla × E. grandis hybrids, information is required regarding the genetic control of certain traits and the correlations between them. A hybrid seedling progeny trial was planted, comprising material generated by controlled pollinations in two within-species ...

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)

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)

Application of Hybrid IC's to the Automotive Electronics Market in Europe

OpenAIRE

Eckart von Roda

1981-01-01

In the last few years hybrids have been increasingly used in automotive electronics in Europe. With examples from the BOSCH and BLAUPUNKT production range their application in regulators, breakerless ignition modules, electronically-controlled fuel injection systems and car radios is illustrated. The elements and techniques used to assemble the hybrids, and the advantages which can be gained are discussed.

Development of an external readout electronics for a hybrid photon detector

CERN Document Server

Uyttenhove, Simon; Tichon, Jacques; Garcia, Salvador

The pixel hybrid photon detectors currently installed in the LHCb Cherenkov system encapsulate readout electronics in the vacuum tube envelope. The LHCb upgrade and the new trigger system will require their replacement with new photon detectors. The baseline photon detector candidate is the multi-anode photomultiplier. A hybrid photon detector with external readout electronics has been proposed as a backup option. This master thesis covers a R & D phase to investigate this latter concept. Extensive studies of the initial electronics system underlined the noise contributions from the Beetle chip used as front-end readout ASIC and from the ceramic carrier of the photon detector. New front-end electronic boards have been developed and made fully compatible with the existing LHCb-RICH infrastructure. With this compact readout system, Cherenkov photons have been successfully detected in a real particle beam environment. The proof-of-concept of a hybrid photon detector with external readout electronics was val...

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.

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

Electron heating using lower hybrid waves in the PLT tokamak

International Nuclear Information System (INIS)

Bell, R.E.; Bernabei, S.; Cavallo, A.; Chu, T.K.; Luce, T.; Motley, R.; Ono, M.; Stevens, J.; von Goeler, S.

1987-06-01

Lower hybrid waves with a narrow high velocity wave spectrum have been used to achieve high central electron temperatures in a tokamak plasma. Waves with a frequency of 2.45 GHz launched by a 16-waveguide grill at a power level less than 600 kW were used to increase the central electron temperature of the PLT plasma from 2.2 keV to 5 keV. The magnitude of the temperature increase depends strongly on the phase difference between the waveguides and on the direction of the launched wave. A reduction in the central electron thermal diffusivity is associated with the peaked electron temperature profiles of lower hybrid current-driven plasmas. 16 refs

Interspecific hybridization and inbreeding effect in seed from a Eucalyptus grandis x E. urophylla clonal orchard in Brazil

Directory of Open Access Journals (Sweden)

Campinhos Eduardo N.

1998-01-01

Full Text Available We used allozyme markers to estimate the amount of natural hybridization between Eucalyptus grandis and E. urophylla in a 7.4-hectare commercial hybrid-seed orchard planted in Espírito Santo, Brazil. This orchard was planted in 1982 using a honeycomb design, with each hexagonal plot containing one E. grandis tree surrounded by six E. urophylla trees. There were 267 replicated hexagonal plots in the orchard. Seeds were harvested from the E. grandis clone only. The multilocus outcrossing rate estimated for the E. grandis clone averaged 70.2%, ranging from 33.0 to 99.0% among individual trees. Contaminant pollination, inferred from progeny genotypes containing alleles not present in the seven parental clones, accounted for 14.4% of the hybrid seed. Contaminant pollen was attributed to neighboring eucalyptus stands isolated from the orchard by a 400-m wide belt of native forest. Inbred and hybrid progenies were identified by their allozyme genotypes and transplanted to the field. Field growth of inbred progeny was 30% lower than that of hybrid plants at two and three years of age.

Cytoplasmic male sterility contributes to hybrid incompatibility between subspecies of Arabidopsis lyrata.

Science.gov (United States)

Aalto, Esa A; Koelewijn, Hans-Peter; Savolainen, Outi

2013-10-03

In crosses between evolutionarily diverged populations, genomic incompatibilities may result in sterile hybrids, indicating evolution of reproductive isolation. In several plant families, crosses within a population can also lead to male sterile progeny because of conflict between the maternally and biparentally inherited genomes. We examined hybrid fertility between subspecies of the perennial outcrossing self-incompatible Lyrate rockcress (Arabidopsis lyrata) in large reciprocal F2 progenies and three generations of backcrosses. In one of the reciprocal F2 progenies, almost one-fourth of the plants were male-sterile. Correspondingly, almost one-half of the plants in one of the four reciprocal backcross progenies expressed male sterility. In an additional four independent F2 and backcross families, three segregated male sterility. The observed asymmetrical hybrid incompatibility is attributable to male sterility factors in one cytoplasm, for which the other population lacks effective fertility restorers. Genotyping of 96 molecular markers and quantitative trait locus mapping revealed that only 60% of the plants having the male sterile cytoplasm and lacking the corresponding restorers were phenotypically male-sterile. Genotyping data showed that there is only one restorer locus, which mapped to a 600-kb interval at the top of chromosome 2 in a region containing a cluster of pentatricopeptide repeat genes. Male fertility showed no trade-off with seed production. We discuss the role of cytoplasm and genomic conflict in incipient speciation and conclude that cytoplasmic male sterility-lowering hybrid fitness is a transient effect with limited potential to form permanent reproductive barriers between diverged populations of hermaphrodite self-incompatible species.

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

Mass production of shortleaf x slash pine hybrids by pollinating unbagged female flowers

Science.gov (United States)

Philip C. Wakeley; O.O. Wells; T.E. Campbell

1966-01-01

A simple method of mass-producing shortleaf x slash pine hybrids was attempted. Large quantities of slash pine pollen were spread on unbagged shortleaf flowers in the hope of recovering a high percentage of hybrid progeny and thus materially reducing the cost of producing such hybrids by conventional controlled pollination. The hybrid is very promising, but, as Snyder...

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.

The structural design and the electron optics of a hybrid electron-ion gun

International Nuclear Information System (INIS)

Bas, E.B.; Gisler, E.; Stucki, F.

1984-01-01

This paper describes a new kind of a particle gun called the hybrid gun. It is able to deliver a finely focused electron or ion beam simply by reversing the polarity of the acceleration voltage. The detailed design features of the gun are given and the electron-ion optical properties are discussed. (author)

Unilateral compatibility and genotypic difference in crossability in interspecific hybridization between Dianthus caryophyllus L. and Dianthus japonicus Thunb.

Science.gov (United States)

Nimura, M; Kato, J; Mii, M; Morioka, K

2003-05-01

Reciprocal interspecific crosses were carried out between six lines of Dianthus caryophyllus L. and one line of Dianthus japonicus Thunb. Although no seed was set when D. japonicus was used as the seed parent, six seedlings were successfully obtained from 2,380 immature ovules by applying the embryo-rescue technique. However, they showed seed parent-like morphology and no evidence for the hybridity by flow cytometry and RAPD analyses. When six lines of D. caryophyllus were used as seed parents, a total of 192 seedlings were successfully obtained without using the embryo-rescue technique. Among these seedlings, 12 out of 25 progenies obtained from the carnation line '98sp1651' were confirmed to be the hybrids. The remaining 13 progenies of this line, and the total 167 progenies obtained from the other carnation lines, had carnation-like morphology without any evidence of hybridity by flow cytometry and RAPD analyses. The progenies confirmed as hybrids had intermediate characters of the parents with respect to leaf width and flower size, but they had a uniform flower color, reddish purple, which was different from that of either parent. Since the hybrids obtained in the present study have some profitable characters such as vigorous growth in summer time, upright robust stem, broad leaves and early flowering, they are expected to be used for the breeding of carnation which is suitable for growing under the Japanese climate.

Interspecific hybridization between Crassostrea angulata and C. ariakensis

Science.gov (United States)

Yao, Tuo; Zhang, Yuehuan; Yan, Xiwu; Wang, Zhaoping; Li, Dongchun; Su, Jiaqi; Yu, Ruihai

2015-08-01

Interspecific hybridization can generate heterosis, which is proven to be a useful tool in selective breeding programs for oyster culture. Crassostrea angulata and C. ariakensis are two important economic shellfish species in China. We conducted 2 × 2 reciprocal crosses to determine whether these two species can cross-fertilize and their hybrids can hatch, survive and perform heterosis. Fertilization was found symmetrical without delay. The rate of fertilization success of C. angulata ♀ × C. ariakensis ♂ was lower than that of C. ariakensis ♀ × C. angulata ♂, and the success rate of both hybridizations was lower than that of two intraspecific crosses each. During the planktonic period, survival rate of the progeny was lower in the hybrid crosses than in the intraspecific crosses. On day 360, mean shell height of the progeny of C. angulata ♀ × C. angulata ♂ was highest, which was followed by that of C. angulata ♀ × C. ariakensis ♂, C. ariakensis ♀ × C. ariakensis ♂ and C. ariakensis ♀ × C. angulata ♂ in a descending order. Morphology of adults produced by the hybrid crosses was similar to that of C. angulata. Both hybrids underwent normal gonad development and produced mature gametes in the mating season. This study provided new insights into the quantitative traits in interspecific crosses of Crassostrea species, thus being of guidance value for selective breeding of oyster.

Electronic Structure Approach to Tunable Electronic Properties of Hybrid Organic-Inorganic Perovskites

Science.gov (United States)

Liu, Garnett; Huhn, William; Mitzi, David B.; Kanai, Yosuke; Blum, Volker

We present a study of the electronic structure of layered hybrid organic-inorganic perovskite (HOIP) materials using all-electron density-functional theory. Varying the nature of the organic and inorganic layers should enable systematically fine-tuning the carrier properties of each component. Using the HSE06 hybrid density functional including spin-orbit coupling (SOC), we validate the principle of tuning subsystem-specific parts of the electron band structures and densities of states in CH3NH3PbX3 (X=Cl, Br, I) compared to a modified organic component in layered (C6H5C2H4NH3) 2PbX4 (X=Cl, Br, I) and C20H22S4N2PbX4 (X=Cl, Br, I). We show that tunable shifts of electronic levels indeed arise by varying Cl, Br, I as the inorganic components, and CH3NH3+ , C6H5C2H4NH3+ , C20H22S4N22 + as the organic components. SOC is found to play an important role in splitting the conduction bands of the HOIP compounds investigated here. The frontier orbitals of the halide shift, increasing the gap, when Cl is substituted for Br and I.

In situ hybridization at the electron microscope level: hybrid detection by autoradiography and colloidal gold.

Science.gov (United States)

Hutchison, N J; Langer-Safer, P R; Ward, D C; Hamkalo, B A

1982-11-01

In situ hybridization has become a standard method for localizing DNA or RNA sequences in cytological preparations. We developed two methods to extend this technique to the transmission electron microscope level using mouse satellite DNA hybridization to whole mount metaphase chromosomes as the test system. The first method devised is a direct extension of standard light microscope level using mouse satellite DNA hybridization to whole mount metaphase chromosomes as the test system. The first method devised is a direct extension of standard light microscope in situ hybridization. Radioactively labeled complementary RNA (cRNA) is hybridized to metaphase chromosomes deposited on electron microscope grids and fixed in 70 percent ethanol vapor; hybridixation site are detected by autoradiography. Specific and intense labeling of chromosomal centromeric regions is observed even after relatively short exposure times. Inerphase nuclei present in some of the metaphase chromosome preparations also show defined paatterms of satellite DNA labeling which suggests that satellite-containing regions are associate with each other during interphase. The sensitivity of this method is estimated to at least as good as that at the light microscope level while the resolution is improved at least threefold. The second method, which circumvents the use of autoradiogrphic detection, uses biotin-labeled polynucleotide probes. After hybridization of these probes, either DNA or RNA, to fixed chromosomes on grids, hybrids are detected via reaction is improved at least threefold. The second method, which circumvents the use of autoradiographic detection, uses biotin-labeled polynucleotide probes. After hybridization of these probes, either DNA or RNA, to fixed chromosomes on grids, hybrids are detected via reaction with an antibody against biotin and secondary antibody adsorbed to the surface of over centromeric heterochromatin and along the associated peripheral fibers. Labeling is on average

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.

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.

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)

Computer simulations of upper-hybrid and electron cyclotron resonance heating

International Nuclear Information System (INIS)

Lin, A.T.; Lin, C.C.

1983-01-01

A 2 1/2 -dimensional relativistic electromagnetic particle code is used to investigate the dynamic behavior of electron heating around the electron cyclotron and upper-hybrid layers when an extraordinary wave is obliquely launched from the high-field side into a magnetized plasma. With a large angle of incidence most of the radiation wave energy converts into electrostatic electron Bernstein waves at the upper-hybrid layer. These mode-converted waves propagate back to the cyclotron layer and deposit their energy in the electrons through resonant interactions dominated first by the Doppler broadening and later by the relativistic mass correction. The line shape for both mechanisms has been observed in the simulations. At a later stage, the relativistic resonance effects shift the peak of the temperature profile to the high-field side. The heating ultimately causes the extraordinary wave to be substantially absorbed by the high-energy electrons. The steep temperature gradient created by the electron cyclotron heating eventually reflects a substantial part of the incident wave energy. The diamagnetic effects due to the gradient of the mode-converted Bernstein wave pressure enhance the spreading of the electron heating from the original electron cyclotron layer

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

DNA fingerprinting of Kentucky bluegrass cultivars and hybrids

Science.gov (United States)

As a high polyploidy, apomictic, self-incompatible, perennial grass, Kentucky bluegrass has such complex genetic architecture that conducting standard Mendelian genetic selection is currently impossible. One large hurdle is the inability to differentiate true hybrids from other apomictic progenies....

Hybrid 3D Printing of Soft Electronics.

Science.gov (United States)

Valentine, Alexander D; Busbee, Travis A; Boley, John William; Raney, Jordan R; Chortos, Alex; Kotikian, Arda; Berrigan, John Daniel; Durstock, Michael F; Lewis, Jennifer A

2017-10-01

Hybrid 3D printing is a new method for producing soft electronics that combines direct ink writing of conductive and dielectric elastomeric materials with automated pick-and-place of surface mount electronic components within an integrated additive manufacturing platform. Using this approach, insulating matrix and conductive electrode inks are directly printed in specific layouts. Passive and active electrical components are then integrated to produce the desired electronic circuitry by using an empty nozzle (in vacuum-on mode) to pick up individual components, place them onto the substrate, and then deposit them (in vacuum-off mode) in the desired location. The components are then interconnected via printed conductive traces to yield soft electronic devices that may find potential application in wearable electronics, soft robotics, and biomedical devices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of lower hybrid fast electron populations on electron temperature measurements at JET

International Nuclear Information System (INIS)

Tanzi, C.P.; Bartlett, D.V.; Schunke, B.

1993-01-01

The Lower Hybrid Current Drive (LHCD) system on JET has to date achieved up to 1.5 MA of driven current. This current is carried by a fast electron population with energies more than ten times the electron temperature and density about 10 -4 of the bulk plasma. This paper discusses the effects of this fast electron population on our ability to make reliable temperature measurements using ECE and reviews the effects on other plasma diagnostics which rely on ECE temperature measurements for their interpretation. (orig.)

A new hybrid code (CHIEF) implementing the inertial electron fluid equation without approximation

Science.gov (United States)

Muñoz, P. A.; Jain, N.; Kilian, P.; Büchner, J.

2018-03-01

We present a new hybrid algorithm implemented in the code CHIEF (Code Hybrid with Inertial Electron Fluid) for simulations of electron-ion plasmas. The algorithm treats the ions kinetically, modeled by the Particle-in-Cell (PiC) method, and electrons as an inertial fluid, modeled by electron fluid equations without any of the approximations used in most of the other hybrid codes with an inertial electron fluid. This kind of code is appropriate to model a large variety of quasineutral plasma phenomena where the electron inertia and/or ion kinetic effects are relevant. We present here the governing equations of the model, how these are discretized and implemented numerically, as well as six test problems to validate our numerical approach. Our chosen test problems, where the electron inertia and ion kinetic effects play the essential role, are: 0) Excitation of parallel eigenmodes to check numerical convergence and stability, 1) parallel (to a background magnetic field) propagating electromagnetic waves, 2) perpendicular propagating electrostatic waves (ion Bernstein modes), 3) ion beam right-hand instability (resonant and non-resonant), 4) ion Landau damping, 5) ion firehose instability, and 6) 2D oblique ion firehose instability. Our results reproduce successfully the predictions of linear and non-linear theory for all these problems, validating our code. All properties of this hybrid code make it ideal to study multi-scale phenomena between electron and ion scales such as collisionless shocks, magnetic reconnection and kinetic plasma turbulence in the dissipation range above the electron scales.

Hybrid functional calculation of electronic and phonon structure of BaSnO3

International Nuclear Information System (INIS)

Kim, Bog G.; Jo, J.Y.; Cheong, S.W.

2013-01-01

Barium stannate, BaSnO 3 (BSO), with a cubic perovskite structure, has been highlighted as a promising host material for the next generation transparent oxide electrodes. This study examined theoretically the electronic structure and phonon structure of BSO using hybrid density functional theory based on the HSE06 functional. The electronic structure results of BSO were corrected by extending the phonon calculations based on the hybrid density functional. The fundamental thermal properties were also predicted based on a hybrid functional calculation. Overall, a detailed understanding of the electronic structure, phonon modes and phonon dispersion of BSO will provide a theoretical starting-point for engineering applications of this material. - Graphical Abstract: (a) Crystal structure of BaSnO 3 . The center ball is Ba and small (red) ball on edge is oxygen and SnO 6 octahedrons are plotted as polyhedron. (b) Electronic band structure along the high symmetry point in the Brillouin zone using the HSE06 hybrid functional. (c) The phonon dispersion curve calculated using the HSE06 hybrid functional (d) Zone center lowest energy F 1u phonon mode. Highlights: ► We report the full hybrid functional calculation of not only the electronic structure but also the phonon structure for BaSnO 3 . ► The band gap calculation of HSE06 revealed an indirect gap with 2.48 eV. ► The effective mass at the conduction band minimum and valence band maximum was calculated. ► In addition, the phonon structure of BSO was calculated using the HSE06 functional. ► Finally, the heat capacity was calculated and compared with the recent experimental result.

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

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

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.

Characterization of anthocyanins in the hybrid progenies derived from Iris dichotoma and I. domestica by HPLC-DAD-ESI/MS analysis.

Science.gov (United States)

Xu, Wenji; Luo, Gangjun; Yu, Fengyang; Jia, Qingxiang; Zheng, Yang; Bi, Xiaoying; Lei, Jiajun

2018-06-01

Iris dichotoma with different flower colors and I. domestica are beardless wild irises belonging to the family Iridaceae that bloom in the summer and have long flowering periods. In this study, we collected three accessions of I. dichotoma with violet, yellow, and white flowers, respectively, in China, and crossed them with I. domestica individuals. The flower color of the hybrids derived from these crosses was categorized into eight groups: violet, purple, brown, orange, red, pink, yellow, and white. From this population, 45 individuals were selected for analysis, and their fully expanded inner and outer perianths were harvested for extraction of anthocyanins. Using high-performance liquid chromatography-mass spectrometry (HPLC-MS) analysis, 29 anthocyanins were identified by comparing MS and UV-visible spectra and elution order based on published data and guidelines. The 29 anthocyanins were classified into six groups: non-acylated glycosides (3RG, 3RG5G), acetylglycosides (3acRG5G), p-coumaroylglycosides (3pCRG, 3pCRG5G), caffeoylglycosides (3CRG5G), feruloylglycosides (3feRG, 3feRG5G), and acetyl-(p-coumaroyl) glycosides (3ac-pCRG5G). Acylated anthocyanin contents were considerably higher than non-acylated anthocyanin contents in the individuals evaluated, regardless of flower color, except in the yellow-flowered I. dichotoma and its yellow-flowered progeny. We found ten anthocyanins derived from pelargonidin, including pelargonidin 3-O-(caffeoyl)rutinoside-5-O-glucoside (Pg3CRG5G), pelargonidin 3-O-(feruloyl)rutinoside-5-O-glucoside (Pg3feRG5G), and pelargonidin 3-O-(feruloyl)rutinoside (Pg3feRG), that have not yet been reported in other Iris species. Moreover, delphinidin 3-O-(feruloyl) rutinoside-5-O-glucoside (Dp3feRG5G), and delphinidin 3-O-(feruloyl)rutinoside (Dp3feRG) were also characterized for the first time in Iris. Two to five major anthocyanins were detected in the petals of the violet and purple groups, whereas those of the brown group

Electronic and magnetic properties of modified silicene/graphene hybrid: Ab initio study

Energy Technology Data Exchange (ETDEWEB)

Chowdhury, Suman; Jana, Debnarayan, E-mail: cujanad@yahoo.com

2016-11-01

Among other two-dimensional (2D) novel materials, graphene and silicene both have drawn intense research interest among the researchers because they possess some unique intriguing properties which can change the scenario of the current electronic industry. In this work we have studied the electronic and the magnetic properties of a new kind of materials which is the hybrid of these two materials. Density functional theory (DFT) has been employed to calculate the relevant electronic and magnetic properties of this hybrid material. The pristine structure is modified by substitutional doping or by creating vacancy (Y-X, where one Y atom (Si or C) has been replaced by one X atom (B, N, Al, P or void)). The calculations have revealed that void systems are unstable while Si-B and Si-N are most stable ones. It has been noticed that some of these doped structures are magnetic in nature having induced mid-gap states in the system. In particular, Si-void structure is unstable yet it possess the highest magnetic moment of the order of 4 μ{sub B} (μ{sub B} being the Bohr magneton). The estimated band gaps of modified silicene/graphene hybrid from spin polarized partial density of states (PDOS) vary between 1.43–2.38 eV and 1.58–2.50 eV for spin-up and spin-down channel respectively. The implication of midgap states has been critically analysed in the light of magnetic nature. This study may be useful to build hybrid spintronic devices with controllable gap for spin up and spin down states. - Graphical abstract: We have studied the electronic and magnetic properties of silicene/graphene hybrid by employing density functional theory (DFT). - Highlights: • Electronic and magnetic properties of two dimensional graphene/silicene hybrid have been explored. • There is no magnetism in the system for a single carbon atom vacancy. • A net magnetic moment of 4.0 Bohr magneton is observed for a single silicon atom vacancy. • Unpaired electrons introduce mid-gap states which

Formation of diploid and triploid hybrid groupers (hybridization of Epinephelus coioides ♀ × Epinephelus lanceolatus ♂) and their 5S gene analysis.

Science.gov (United States)

Huang, Wen; Qin, Qinbo; Yang, Huirong; Li, Shuisheng; Hu, Chaoqun; Wang, Yude; Zhang, Yong; Liu, Shaojun; Lin, Haoran

2016-10-07

Interspecies hybridization is widely used to achieve heterosis or hybrid vigor, which has been observed and harnessed by breeders for centuries. Natural allopolyploid hybrids generally exhibit more superior heterosis than both the diploid progenies and their parental species. However, polyploid formation processes have been long ignored, the genetic basis of heterosis in polyploids remains elusive. In the present study, triploid hybrids had been demonstrated to contain two sets of chromosomes from mother species and one set from father species. Cellular polyploidization process in the embryos had been traced. The triploid hybrids might be formed by failure formation of the second polarized genome during the second meiosis stage. Four spindle centers were observed in anaphase stage of the first cell division. Three spindle centers were observed in side of cell plate after the first cell division. The 5S rDNA genes of four types of groupers were cloned and analyzed. The diploid and triploid hybrids had been proved to contain the tandem chimera structures which were recombined by maternal and paternal monomer units. The results indicated that genome re-fusion had occurred in the hybrid progenies. To further elucidate the genetic patterns of diploid and triploid hybrids, fluorescence chromosome location had been carried out, maternal 5S gene (M-386) were used as the probe. The triploid hybrids contained fewer fluorescence loci numbers than the maternal species. The results indicated that participation of paternal 5S gene in the triploid hybrid genome had degraded the match rates of M-386 probe. Our study is the first to investigate the cellular formation processes of natural allopolyploids in hybrid fish, the cellular polyploidization process may be caused by failure formation of the second polarized genome during the meiosis, and our results will provide the molecular basis of hybrid vigor in interspecies hybridization.

Inheritance of oilseed rape (Brassica napus) RAPD markers in a backcross progeny with Brassica campestris

DEFF Research Database (Denmark)

Mikkelsen, T.R.; Jensen, J.; Bagger Jørgensen, Rikke

1996-01-01

Different cultivars/transgenic lines of oilseed rape (Brassica napus) were crossed (as females) with different cultivars/populations of Brassica campestris. All cross combinations produced seed, with an average seed set per pollination of 9.8. Backcrossing of selected interspecific hybrids (as...... females) to B. campestris resulted in a much lower seed set, average 0.7 seed per pollination. In the single backcross progeny where a large enough population (92 plants) was obtained for analysis, 33 B. napus specific RAPD markers were investigated to determine the extent of transfer of oilseed rape...

Electron transport properties in ZnO nanowires/poly(3-hexylthiophene) hybrid nanostructure

International Nuclear Information System (INIS)

Cheng Ke; Cheng Gang; Wang Shujie; Fu Dongwei; Zou Bingsuo; Du Zuliang

2010-01-01

The ZnO nanowires (NWs) array/poly(3-hexylthiophene) (P3HT) hybrid prototype device was fabricated. An ultraviolet (UV) light of λ = 350 nm is used to investigate the photo-electric properties of the ZnO NWs array and hybrid structure. In this way, we can avoid the excitation of P3HT, which can give us a real electron transport ability of ZnO NWs itself. Our results demonstrated a higher and faster photo-electric response of 3 s for the hybrid structure while 9 s for the ZnO NWs array. The surface states related slow photo-electric response was also observed for them. The charge transfer mechanism and the influence of surface states were discussed. The current work provides us profound understandings on the electron transport ability of ZnO NWs array in a working hybrid polymer solar cell, which is crucial for optimizing the device performance.

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...

Modified electron-acoustic and lower-hybrid drift dissipative instability in a two-electron temperature plasma

International Nuclear Information System (INIS)

Bose, M.

1989-01-01

It is often found, in fusion devices as well as in the auroral ionosphere, that the electrons consist of two distinct group, viz., hot and cold. These two-temperature electron model is sometimes convenient for analytical purposes. Thus the authors have considered a two-temperature electron plasma. In this paper, they investigated analytically the drift dissipative instabilities of modified electron-acoustic and lower-hybrid wve in a two-electron temperature plasma. It is found that the modified electron-acoustic drift dissipative mode are strongly dependent on the number density of cold electrons. From the expression of the growth rate, it is clear that these cold electrons can control the growth of this mode as well

Somatically segregating clone of apomictic maize-tripsacum hybrid

International Nuclear Information System (INIS)

Yudin, B.F.; Lukina, L.A.

1988-01-01

The results of further study on clone AM-5, isolated in the progeny of γ-irradiated plants of the apomictic hybrid of maize with tripsacum (2n = 38) are reported. The variegated-leaf seedlings of the clone segregate somatically and produce variegated, mottled, green (phenotypically normal) plants in different ratios in the apomictic progenies. The variegated, and to a lesser degree, green segregants segregate further. The mottled apomictics as well as mottled branches of variegated seedlings maintain their phenotype on transplantation, however, these is a progressive enhancement of the characters of vegetative lethality. Lethals of two extra maize genomes to the AM-5 nucleus does not affect significantly the scope and nature of segregation. At the same time, the loss of tripsacum genome restores normal phenotype. Clone AM-5 is an example of hybrid apomictic form causing significant morphological variability, which is, nevertheless, not related with apomictic and reversion to the sexual process

Evidence for the Emergence of New Rice Types of Interspecific Hybrid Origin in West African Farmers' Fields

NARCIS (Netherlands)

Nuijten, H.A.C.P.; Treuren, van R.; Struik, P.C.; Mokuwa, G.A.; Okry, F.; Teeken, B.W.E.; Richards, P.

2009-01-01

In West Africa two rice species (Oryza glaberrima Steud. and Oryza sativa L.) co-exist. Although originally it was thought that interspecific hybridization is impossible without biotechnological methods, progenies of hybridization appear to occur in farmer fields. AFLP analysis was used to assess

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

Inheritance of spike length in F3, F4 and F5 wheat hybrids obtained by different selection methods

Directory of Open Access Journals (Sweden)

Janković Snežana

2012-01-01

Full Text Available This study analyses the mode of inheritance of spike length in F3, F4 and F5 wheat hybrids obtained by pedigree, bulk and modified pedigree method of selection. Wheat hybrids were produced after crossing five varieties by M x N method. Three varieties were used as a female parent (Briscard, Carifen 12 and Rescler and two as a male component (Francuska and PKB-Prelivka. Descendents in F2 generation were produced from 6 F1 hybrids (3 x 2. Selection after F2 generation were undertaken from 1996 to 1999, while in 2000 the field experiments with complete breeding material were set up at the Institute 'PKB INI Agroekonomik' in Padinska Skela near Belgrade. Spike length was measured in progeny generations, from F3 to F5. It was observed that progenies had higher values for spike length than better parent (BP, with longer spikes in 5 out of 6 analyzed hybrids: Briscard x PKB-Prelivka, Carifen 12 x Francuska, Carifen 12 x PKB-Prelivka, Rescler x Francuska, and Rescler x PKB-Prelivka. From the above mentioned hybrid combinations, only Rescler x Francuska descendents in F5 generation obtained by pedigree and bulk selection inherited the spike length from the parent with lower value. High significant interaction was observed for spike length between genotype and generation of progenies in each of the applied selection methods.

Low-voltage protonic/electronic hybrid indium zinc oxide synaptic transistors on paper substrates

International Nuclear Information System (INIS)

Wu, Guodong; Wan, Changjin; Wan, Qing; Zhou, Jumei; Zhu, Liqiang

2014-01-01

Low-voltage (1.5 V) indium zinc oxide (IZO)-based electric-double-layer (EDL) thin-film transistors (TFTs) gated by nanogranular proton conducting SiO 2 electrolyte films are fabricated on paper substrates. Both enhancement-mode and depletion-mode operation are obtained by tuning the thickness of the IZO channel layer. Furthermore, such flexible IZO protonic/electronic hybrid EDL TFTs can be used as artificial synapses, and synaptic stimulation response and short-term synaptic plasticity function are demonstrated. The protonic/electronic hybrid EDL TFTs on paper substrates proposed here are promising for low-power flexible paper electronics, artificial synapses and bioelectronics. (paper)

Methods for fabrication of flexible hybrid electronics

Science.gov (United States)

Street, Robert A.; Mei, Ping; Krusor, Brent; Ready, Steve E.; Zhang, Yong; Schwartz, David E.; Pierre, Adrien; Doris, Sean E.; Russo, Beverly; Kor, Siv; Veres, Janos

2017-08-01

Printed and flexible hybrid electronics is an emerging technology with potential applications in smart labels, wearable electronics, soft robotics, and prosthetics. Printed solution-based materials are compatible with plastic film substrates that are flexible, soft, and stretchable, thus enabling conformal integration with non-planar objects. In addition, manufacturing by printing is scalable to large areas and is amenable to low-cost sheet-fed and roll-to-roll processes. FHE includes display and sensory components to interface with users and environments. On the system level, devices also require electronic circuits for power, memory, signal conditioning, and communications. Those electronic components can be integrated onto a flexible substrate by either assembly or printing. PARC has developed systems and processes for realizing both approaches. This talk presents fabrication methods with an emphasis on techniques recently developed for the assembly of off-the-shelf chips. A few examples of systems fabricated with this approach are also described.

Mapping the electrostatic potential of Au nanoparticles using hybrid electron holography.

Science.gov (United States)

Ozsoy-Keskinbora, Cigdem; Boothroyd, Chris B; Dunin-Borkowski, Rafal E; van Aken, Peter A; Koch, Christoph T

2016-06-01

Electron holography is a powerful technique for characterizing electrostatic potentials, charge distributions, electric and magnetic fields, strain distributions and semiconductor dopant distributions with sub-nm spatial resolution. Mapping internal electrostatic and magnetic fields within nanoparticles and other low-dimensional materials by TEM requires both high spatial resolution and high phase sensitivity. Carrying out such an analysis fully quantitatively is even more challenging, since artefacts such as dynamical electron scattering may strongly affect the measurement. In-line electron holography, one of the variants of electron holography, features high phase sensitivity at high spatial frequencies, but suffers from inefficient phase recovery at low spatial frequencies. Off-axis electron holography, in contrast, can recover low spatial frequency phase information much more reliably, but is less effective in retrieving phase information at high spatial frequencies when compared to in-line holography. We investigate gold nanoparticles using hybrid electron holography at both atomic-resolution and intermediate magnification. Hybrid electron holography is a novel technique that synergistically combines off-axis and in-line electron holography, allowing the measurement of the complex wave function describing the scattered electrons with excellent signal-to-noise properties at both high and low spatial frequencies. The effect of dynamical electron scattering is minimized by beam tilt averaging. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

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

The hybridized front end electronics of the Central Drift Chamber in the Stanford Linear Collider Detector

International Nuclear Information System (INIS)

Lo, C.C.; Kirsten, F.A.; Nakamura, M.

1987-10-01

In order to accommodate the high packaging density requirements for the front end electronics of the Central Drift Chamber (CDC) in the SLAC Linear Collider Detector (SLD), the CDC front end electronics has been hybridized. The hybrid package contains eight channels of amplifiers together with all the associated circuits for calibration, event recognition and power economy switching functions. A total of 1280 such hybrids are used in the CDC

Genetic parameters and estimated genetic gains in young rubber tree progenies

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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.

A Hybrid System Based on an Electronic Nose Coupled with an Electronic Tongue for the Characterization of Moroccan Waters

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Z. Haddi

2014-05-01

Full Text Available A hybrid multisensor system combined with multivariate analysis was applied to the characterization of different kinds of Moroccan waters. The proposed hybrid system based on an electronic nose coupled with an electronic tongue consisted of metal oxide semiconductors and potentiometric sensors respectively. Five Taguchi Gas Sensors were implemented in the electronic nose for the discrimination between mineral, natural, sparkling, river and tap waters. Afterwards, the electronic tongue, based on series of Ion-Selective-Electrodes was applied to the analysis of the same waters. Multisensor responses obtained from the waters were processed by two chemometrics: Principal Component Analysis (PCA and Linear Discriminant Analysis (LDA. PCA results using electronic nose data depict all of the potable water samples in a separate group from the samples that were originated from river. Furthermore, PCA and LDA analysis on electronic tongue data permitted clear and rapid recognizing of the different waters due to the concentration changes of the chemical parameters from source to another.

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

Superhard sp2–sp3 hybrid carbon allotropes with tunable electronic properties

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Meng Hu

2016-05-01

Full Text Available Four sp2–sp3 hybrid carbon allotropes are proposed on the basis of first principles calculations. These four carbon allotropes are energetically more favorable than graphite under suitable pressure conditions. They can be assembled from graphite through intralayer wrinkling and interlayer buckling, which is similar to the formation of diamond from graphite. For one of the sp2–sp3 hybrid carbon allotropes, mC24, the electron diffraction patterns match these of i-carbon, which is synthesized from shock-compressed graphite (H. Hirai and K. Kondo, Science, 1991, 253, 772. The allotropes exhibit tunable electronic characteristics from metallic to semiconductive with band gaps comparable to those of silicon allotropes. They are all superhard materials with Vickers hardness values comparable to that of cubic BN. The sp2–sp3 hybrid carbon allotroes are promising materials for photovoltaic electronic devices, and abrasive and grinding tools.

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

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)

Hybridization alters spontaneous mutation rates in a parent-of-origin-dependent fashion in Arabidopsis.

Science.gov (United States)

Bashir, Tufail; Sailer, Christian; Gerber, Florian; Loganathan, Nitin; Bhoopalan, Hemadev; Eichenberger, Christof; Grossniklaus, Ueli; Baskar, Ramamurthy

2014-05-01

Over 70 years ago, increased spontaneous mutation rates were observed in Drosophila spp. hybrids, but the genetic basis of this phenomenon is not well understood. The model plant Arabidopsis (Arabidopsis thaliana) offers unique opportunities to study the types of mutations induced upon hybridization and the frequency of their occurrence. Understanding the mutational effects of hybridization is important, as many crop plants are grown as hybrids. Besides, hybridization is important for speciation and its effects on genome integrity could be critical, as chromosomal rearrangements can lead to reproductive isolation. We examined the rates of hybridization-induced point and frameshift mutations as well as homologous recombination events in intraspecific Arabidopsis hybrids using a set of transgenic mutation detector lines that carry mutated or truncated versions of a reporter gene. We found that hybridization alters the frequency of different kinds of mutations. In general, Columbia (Col)×Cape Verde Islands and Col×C24 hybrid progeny had decreased T→G and T→A transversion rates but an increased C→T transition rate. Significant changes in frameshift mutation rates were also observed in some hybrids. In Col×C24 hybrids, there is a trend for increased homologous recombination rates, except for the hybrids from one line, while in Col×Cape Verde Islands hybrids, this rate is decreased. The overall genetic distance of the parents had no influence on mutation rates in the progeny, as closely related accessions on occasion displayed higher mutation rates than accessions that are separated farther apart. However, reciprocal hybrids had significantly different mutation rates, suggesting parent-of-origin-dependent effects on the mutation frequency.

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)

Alteration of terminal heterochromatin and chromosome rearrangements in derivatives of wheat-rye hybrids.

Science.gov (United States)

Fu, Shulan; Lv, Zhenling; Guo, Xiang; Zhang, Xiangqi; Han, Fangpu

2013-08-20

Wheat-rye addition and substitution lines and their self progenies revealed variations in telomeric heterochromatin and centromeres. Furthermore, a mitotically unstable dicentric chromosome and stable multicentric chromosomes were observed in the progeny of a Chinese Spring-Imperial rye 3R addition line. An unstable multicentric chromosome was found in the progeny of a 6R/6D substitution line. Drastic variation of terminal heterochromatin including movement and disappearance of terminal heterochromatin occurred in the progeny of wheat-rye addition line 3R, and the 5RS ditelosomic addition line. Highly stable minichromosomes were observed in the progeny of a monosomic 4R addition line, a ditelosomic 5RS addition line and a 6R/6D substitution line. Minichromosomes, with and without the FISH signals for telomeric DNA (TTTAGGG)n, derived from a monosomic 4R addition line are stable and transmissible to the next generation. The results indicated that centromeres and terminal heterochromatin can be profoundly altered in wheat-rye hybrid derivatives. Copyright © 2013. Published by Elsevier Ltd.

Removal of VOCs by hybrid electron beam reactor with catalyst bed

International Nuclear Information System (INIS)

Kim, Jinkyu; Han, Bumsoo; Kim, Yuri; Lee, J.H.; Park, C.R.; Kim, J.C.; Kim, J.C.; Kim, K.J.

2004-01-01

Electron beam decomposition of volatile organic compounds (VOCs) was studied in order to obtain information for developing effective treatment method of off-gases from industries. We have examined the combination of electron beam and catalyst honeycomb which is either 1% platinum based or ceramic honeycomb- based aluminum oxide, using a hybrid reactor in order to improve removal efficiency and CO 2 formation; and to suppress undesirable by-product formation e.g. O 3 , aerosol, H x C y. , and tar. The experiments were conducted using a pilot-scale treatment system (maximum capacity; 1800 N m 3 /h) that fitted the field size to scale up from the traditional laboratory scale system for VOC removal with electron beam irradiation. Toluene was selected as a typical VOC that was irradiated to investigate product formation, effect of ceramic and catalyst, and factors effecting overall efficiency of degradation. Styrene was selected as the most odorous compound among the VOCs of interest. It was found that VOCs could be destroyed more effectively using a hybrid system with catalyst bed than with electron beam irradiation only

Diagnostics of ballistic electrons in a dc/rf hybrid capacitively coupled discharge

International Nuclear Information System (INIS)

Xu Lin; Chen, Lee; Funk, Merritt; Ranjan, Alok; Hummel, Mike; Bravenec, Ron; Sundararajan, Radha; Economou, Demetre J.; Donnelly, Vincent M.

2008-01-01

The energy distribution of ballistic electrons in a dc/rf hybrid parallel-plate capacitively coupled plasma reactor was measured. Ballistic electrons originated as secondaries produced by ion and electron bombardment of the electrodes. The energy distribution of ballistic electrons peaked at the value of the negative bias applied to the dc electrode. As that bias became more negative, the ballistic electron current on the rf substrate electrode increased dramatically. The ion current on the dc electrode also increased

Cross effects on electron-cyclotron and lower-hybrid current drive in tokamak plasmas

International Nuclear Information System (INIS)

Fidone, I.; Giruzzi, G.; Krivenski, V.; Mazzucato, E.; Ziebell, L.F.

1986-11-01

Electron cyclotron resonance current drive in a tokamak plasma in the presence of a lower hybrid tail is investigated using a 2D Fokker-Planck code. For an extraordinary mode at oblique propagation and down-shifted frequency it is shown that the efficiency of electron cyclotron current drive becomes, i) substantially greater than the corresponding efficiency of a Maxwellian plasma at the same bulk temperature, ii) equal or greater than that of the lower hybrid waves, iii) comparable with the efficiency of a Maxwellian plasma at much higher temperature. This enhancement results from a beneficial cross-effect of the two waves on the formation of the current carrying electron tail. (5 fig; 17 refs)

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.

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.

Factors affecting daughters distribution among progeny testing Holstein bulls

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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.

The Hybridization Barrier between Herbaceous Medicago sativa and Woody M. arborea Is Weakened by Selection of Seed Parents

Directory of Open Access Journals (Sweden)

Edwin Bingham

2013-05-01

Full Text Available Medicago sativa, alfalfa or lucerne, and M. arborea were considered reproductively isolated until recently. Then, in 2003, an alfalfa genotype was identified that produced a few seeds and progeny with hybrid traits after a large number of pollinations by M. arborea. A derivative of this alfalfa genotype also produced a low frequency of progeny with hybrid traits. Thus, the hybridization barrier was weakened by selection of seed parents. Hybrids from both events expressed traits from M. arborea and M. arborea-specific DNA bands, although more of the M. sativa genome was retained, based on the DNA results. Thus, there was chromatin elimination during embryogenesis, resulting in partial hybrids (hereafter hybrids. However, more than 30 hybrids with an array of M. arborea traits have been obtained thus far, and research continues on the nature of the hybrids. Traits have been genetically transmitted in crosses, and selected traits are in use for alfalfa breeding. This paper reviews the first hybrids and then focuses on further weakening of the hybridization barrier with the discovery of a more efficient hybridizer derived from crossing Medicago sativa subspecies, sativa, coerulea and falcata. This genotype was found to have reproductive abnormalities associated with its complex subspecies origin that are best described as hybrid breakdown. In effect, this subspecies derivative is a bridge-cross parent that consistently produces hybrids. Reproductive abnormalities in the bridge-cross parent are reported and discussed.

The Hybridization Barrier between Herbaceous Medicago sativa and Woody M. arborea Is Weakened by Selection of Seed Parents

Science.gov (United States)

Bingham, Edwin; Armour, David; Irwin, John

2013-01-01

Medicago sativa, alfalfa or lucerne, and M. arborea were considered reproductively isolated until recently. Then, in 2003, an alfalfa genotype was identified that produced a few seeds and progeny with hybrid traits after a large number of pollinations by M. arborea. A derivative of this alfalfa genotype also produced a low frequency of progeny with hybrid traits. Thus, the hybridization barrier was weakened by selection of seed parents. Hybrids from both events expressed traits from M. arborea and M. arborea-specific DNA bands, although more of the M. sativa genome was retained, based on the DNA results. Thus, there was chromatin elimination during embryogenesis, resulting in partial hybrids (hereafter hybrids). However, more than 30 hybrids with an array of M. arborea traits have been obtained thus far, and research continues on the nature of the hybrids. Traits have been genetically transmitted in crosses, and selected traits are in use for alfalfa breeding. This paper reviews the first hybrids and then focuses on further weakening of the hybridization barrier with the discovery of a more efficient hybridizer derived from crossing Medicago sativa subspecies, sativa, coerulea and falcata. This genotype was found to have reproductive abnormalities associated with its complex subspecies origin that are best described as hybrid breakdown. In effect, this subspecies derivative is a bridge-cross parent that consistently produces hybrids. Reproductive abnormalities in the bridge-cross parent are reported and discussed. PMID:27137379

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.

Interfacial characterization of flexible hybrid electronics

Science.gov (United States)

Najafian, Sara; Amirkhizi, Alireza V.; Stapleton, Scott

2018-03-01

Flexible Hybrid Electronics (FHEs) are the new generation of electronics combining flexible plastic film substrates with electronic devices. Besides the electrical features, design improvements of FHEs depend on the prediction of their mechanical and failure behavior. Debonding of electronic components from the flexible substrate is one of the most common and critical failures of these devices, therefore, the experimental determination of material and interface properties is of great importance in the prediction of failure mechanisms. Traditional interface characterization involves isolated shear and normal mode tests such as the double cantilever beam (DCB) and end notch flexure (ENF) tests. However, due to the thin, flexible nature of the materials and manufacturing restrictions, tests mirroring traditional interface characterization experiments may not always be possible. The ideal goal of this research is to design experiments such that each mode of fracture is isolated. However, due to the complex nonlinear nature of the response and small geometries of FHEs, design of the proper tests to characterize the interface properties can be significantly time and cost consuming. Hence numerical modeling has been implemented to design these novel characterization experiments. This research involves loading case and specimen geometry parametric studies using numerical modeling to design future experiments where either shear or normal fracture modes are dominant. These virtual experiments will provide a foundation for designing similar tests for many different types of flexible electronics and predicting the failure mechanism independent of the specific FHE materials.

A review and design of power electronics converters for fuel cell hybrid system applications

DEFF Research Database (Denmark)

Zhang, Zhe; Pittini, Riccardo; Andersen, Michael A. E.

2012-01-01

This paper presents an overview of most promising power electronics topologies for a fuel cell hybrid power conversion system which can be utilized in many applications such as hybrid electrical vehicles (HEV), distributed generations (DG) and uninterruptible-power-supply (UPS) systems. Then...

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)

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)

Enhanced coupling of the fast wave to electrons through mode conversion to the ion hybrid wave

International Nuclear Information System (INIS)

Lashmore-Davies, C.N.; Fuchs, V.; Ram, A.K.; Bers, A.

1996-07-01

The mode conversion of the fast compressional Alfven wave to the ion hybrid wave is analyzed with particular reference to a plasma with two ion species present in approximately equal proportions. Two configurations are considered, the first referring to the usual resonance-cut-off case and the second to a cut-off-resonance-cut-off situation. The optimum conditions for maximising the mode converted energy are given. The second order fast wave equation is generalised to include the effect of the parallel electric field. Hence, all ion and electron loss mechanisms for the fast wave are incorporated, including mode conversion at the two-ion hybrid resonance. The significance of the approximate equality of the two ion species concentrations is that the mode converted ion hybrid wave is damped only by the electrons. The damping of the ion hybrid wave is described with the aid of the local dispersion relation and by means of a toroidal ray tracing code. In particular, the ray tracing calculation shows that the mode converted energy is totally absorbed by the electrons close to the two-ion hybrid resonance. The generalised fast wave equation is solved to determine how much energy is lost from the fast wave, incident from the low field side, before it encounters the two-ion hybrid resonance. For comparable concentrations of the two ion species, the mode converted power can be separated from the power directly absorbed by the ions and electrons from the fast wave. This allows the conditions to be ascertained under which strong electron heating through mode conversion dominates the direct dissipation of the fast wave. (UK)

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.

Electron imaging with Medipix2 hybrid pixel detector

CERN Document Server

McMullan, G; Chen, S; Henderson, R; Llopart, X; Summerfield, C; Tlustos, L; Faruqi, A R

2007-01-01

The electron imaging performance of Medipix2 is described. Medipix2 is a hybrid pixel detector composed of two layers. It has a sensor layer and a layer of readout electronics, in which each 55 μm×55 μm pixel has upper and lower energy discrimination and MHz rate counting. The sensor layer consists of a 300 μm slab of pixellated monolithic silicon and this is bonded to the readout chip. Experimental measurement of the detective quantum efficiency, DQE(0) at 120 keV shows that it can reach 85% independent of electron exposure, since the detector has zero noise, and the DQE(Nyquist) can reach 35% of that expected for a perfect detector (4/π2). Experimental measurement of the modulation transfer function (MTF) at Nyquist resolution for 120 keV electrons using a 60 keV lower energy threshold, yields a value that is 50% of that expected for a perfect detector (2/π). Finally, Monte Carlo simulations of electron tracks and energy deposited in adjacent pixels have been performed and used to calculate expected v...

Lower-hybrid wave penetration and effects on electron population

International Nuclear Information System (INIS)

Dupas, L.; Grelot, P.; Parlange, F.; Weisse, J.

1981-01-01

In a high-power-density lower-hybrid experiment (approximately 10kW.cm -2 ), a parallel index spectrum was measured and the radial position where sidebands are excited was deduced from pump and sideband wavenumber measurements. On this basis, some considerations on wave propagation are given which are compatible with some effects observed on electron population. (author)

Hybrid fluorescence and electron cryo-microscopy for simultaneous electron and photon imaging.

Science.gov (United States)

Iijima, Hirofumi; Fukuda, Yoshiyuki; Arai, Yoshihiro; Terakawa, Susumu; Yamamoto, Naoki; Nagayama, Kuniaki

2014-01-01

Integration of fluorescence light and transmission electron microscopy into the same device would represent an important advance in correlative microscopy, which traditionally involves two separate microscopes for imaging. To achieve such integration, the primary technical challenge that must be solved regards how to arrange two objective lenses used for light and electron microscopy in such a manner that they can properly focus on a single specimen. To address this issue, both lateral displacement of the specimen between two lenses and specimen rotation have been proposed. Such movement of the specimen allows sequential collection of two kinds of microscopic images of a single target, but prevents simultaneous imaging. This shortcoming has been made up by using a simple optical device, a reflection mirror. Here, we present an approach toward the versatile integration of fluorescence and electron microscopy for simultaneous imaging. The potential of simultaneous hybrid microscopy was demonstrated by fluorescence and electron sequential imaging of a fluorescent protein expressed in cells and cathodoluminescence imaging of fluorescent beads. Copyright © 2013 Elsevier Inc. All rights reserved.

Excitation of lower hybrid waves by electron beams in finite geometry plasmas

International Nuclear Information System (INIS)

Shoucri, M.m.; Gagne, R.R.J.

1978-01-01

The quasi-static lower hybrid eigenmodes of a plasma column in a cylindrical waveguide are determined, and their linear excitation by a small density electron beam is discussed for the cases of a hot electron beam as well as for a cold electron beam. It is shown that under certain conditions, finite geometry effects introduce important quantitative and qualitative differences with respect to the results obtained in an infinite geometry. (author)

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)

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)

Some results of applied interspecific hybridization in sunflower breeding

International Nuclear Information System (INIS)

Tsvetkova, F.

1976-01-01

Investigations on the interspecific hybridization in sunflower, aimed at developing a diversified initial selection material, were carried out Wild species of the diploid, tetraploid and hexaploid groups, varieties, hybrids, and selfed-lines of cultivated sunflower were used for crossings. To overcome incrossability between the species and sterility in the hybrids the method of f;cilitating of crossability by mutual gra'fting and gamma-rays treatment of seeds and pollen were applied. Results showed that: 1. By the method of interspecific hybridization forms might be produced resistant to more important diseases. 2. Interspecific hybridization in combination with other methods of selection might produce varieties and hybrids with a complex of valuable qualities. 3. Crossings between wild species and cultivated sunflower gave progenies with gene rale sterility. 4. The species H.tuberosus, H.scaberimus, H.arωphylus and H.lenticularis possess genes of full fertility restoration. (author)

Valence electronic structure of cobalt phthalocyanine from an optimally tuned range-separated hybrid functional.

Science.gov (United States)

Brumboiu, Iulia Emilia; Prokopiou, Georgia; Kronik, Leeor; Brena, Barbara

2017-07-28

We analyse the valence electronic structure of cobalt phthalocyanine (CoPc) by means of optimally tuning a range-separated hybrid functional. The tuning is performed by modifying both the amount of short-range exact exchange (α) included in the hybrid functional and the range-separation parameter (γ), with two strategies employed for finding the optimal γ for each α. The influence of these two parameters on the structural, electronic, and magnetic properties of CoPc is thoroughly investigated. The electronic structure is found to be very sensitive to the amount and range in which the exact exchange is included. The electronic structure obtained using the optimal parameters is compared to gas-phase photo-electron data and GW calculations, with the unoccupied states additionally compared with inverse photo-electron spectroscopy measurements. The calculated spectrum with tuned γ, determined for the optimal value of α = 0.1, yields a very good agreement with both experimental results and with GW calculations that well-reproduce the experimental data.

Generation of runaway electrons during deterioration of lower hybrid power coupling in lower hybrid current drive plasmas in the HT-7 tokamak

International Nuclear Information System (INIS)

Chen, Z Y; Ju, H J; Zhu, J X; Li, M; Cai, W D; Liang, H F; Wan, B N; Shi, Y J; Xu, H D

2009-01-01

Efficient coupling of lower hybrid (LH) power from the wave launcher to the plasma is a very important issue in lower hybrid current drive (LHCD) experiments. The large unbalanced reflections in the grill trigger the LH protection system, which will trip the power, resulting in the reduction of the coupled LH power. The generation of runaway electrons has been investigated in LHCD plasmas with deterioration of LH coupling in the HT-7 tokamak. The deterioration of LH coupling results in an increase of the loop voltage and a more energetic fast electron population. These two effects favor the generation of a runaway population. It is found that most of the fast electrons generated by LH waves through parallel electron Landau damping were converted into a runaway population through the acceleration from the toroidal electric field when significant deterioration of LH coupling occurs.

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

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)

A hybrid gyrokinetic ion and isothermal electron fluid code for astrophysical plasma

Science.gov (United States)

Kawazura, Y.; Barnes, M.

2018-05-01

This paper describes a new code for simulating astrophysical plasmas that solves a hybrid model composed of gyrokinetic ions (GKI) and an isothermal electron fluid (ITEF) Schekochihin et al. (2009) [9]. This model captures ion kinetic effects that are important near the ion gyro-radius scale while electron kinetic effects are ordered out by an electron-ion mass ratio expansion. The code is developed by incorporating the ITEF approximation into AstroGK, an Eulerian δf gyrokinetics code specialized to a slab geometry Numata et al. (2010) [41]. The new code treats the linear terms in the ITEF equations implicitly while the nonlinear terms are treated explicitly. We show linear and nonlinear benchmark tests to prove the validity and applicability of the simulation code. Since the fast electron timescale is eliminated by the mass ratio expansion, the Courant-Friedrichs-Lewy condition is much less restrictive than in full gyrokinetic codes; the present hybrid code runs ∼ 2√{mi /me } ∼ 100 times faster than AstroGK with a single ion species and kinetic electrons where mi /me is the ion-electron mass ratio. The improvement of the computational time makes it feasible to execute ion scale gyrokinetic simulations with a high velocity space resolution and to run multiple simulations to determine the dependence of turbulent dynamics on parameters such as electron-ion temperature ratio and plasma beta.

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

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

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.

Monitoring of beer fermentation based on hybrid electronic tongue.

Science.gov (United States)

Kutyła-Olesiuk, Anna; Zaborowski, Michał; Prokaryn, Piotr; Ciosek, Patrycja

2012-10-01

Monitoring of biotechnological processes, including fermentation is extremely important because of the rapidly occurring changes in the composition of the samples during the production. In the case of beer, the analysis of physicochemical parameters allows for the determination of the stage of fermentation process and the control of its possible perturbations. As a tool to control the beer production process a sensor array can be used, composed of potentiometric and voltammetric sensors (so-called hybrid Electronic Tongue, h-ET). The aim of this study is to apply electronic tongue system to distinguish samples obtained during alcoholic fermentation. The samples originate from batch of homemade beer fermentation and from two stages of the process: fermentation reaction and maturation of beer. The applied sensor array consists of 10 miniaturized ion-selective electrodes (potentiometric ET) and silicon based 3-electrode voltammetric transducers (voltammetric ET). The obtained results were processed using Partial Least Squares (PLS) and Partial Least Squares-Discriminant Analysis (PLS-DA). For potentiometric data, voltammetric data, and combined potentiometric and voltammetric data, comparison of the classification ability was conducted based on Root Mean Squared Error (RMSE), sensitivity, specificity, and coefficient F calculation. It is shown, that in the contrast to the separately used techniques, the developed hybrid system allowed for a better characterization of the beer samples. Data fusion in hybrid ET enables to obtain better results both in qualitative analysis (RMSE, specificity, sensitivity) and in quantitative analysis (RMSE, R(2), a, b). Copyright © 2012 Elsevier B.V. All rights reserved.

Polymer-metal hybrid transparent electrodes for flexible electronics

Science.gov (United States)

Kang, Hongkyu; Jung, Suhyun; Jeong, Soyeong; Kim, Geunjin; Lee, Kwanghee

2015-03-01

Despite nearly two decades of research, the absence of ideal flexible and transparent electrodes has been the largest obstacle in realizing flexible and printable electronics for future technologies. Here we report the fabrication of ‘polymer-metal hybrid electrodes’ with high-performance properties, including a bending radius 95% and a sheet resistance solar cells that exhibit a high power conversion efficiency of 10% and polymer light-emitting diodes that can outperform those based on transparent conducting oxides.

Ultrafast optical snapshots of hybrid perovskites reveal the origin of multiband electronic transitions

Science.gov (United States)

Appavoo, Kannatassen; Nie, Wanyi; Blancon, Jean-Christophe; Even, Jacky; Mohite, Aditya D.; Sfeir, Matthew Y.

2017-11-01

Connecting the complex electronic excitations of hybrid perovskites to their intricate organic-inorganic lattice structure has critical implications for energy conversion and optoelectronic technologies. Here we detail the multiband, multivalley electronic structure of a halide hybrid perovskite by measuring the absorption transients of a millimeter-scale-grain thin film as it undergoes a thermally controlled reversible tetragonal-to-orthogonal phase transition. Probing nearly single grains of this hybrid perovskite, we observe an unreported energy splitting (degeneracy lifting) of the high-energy 2.6 eV band in the tetragonal phase that further splits as the rotational degrees of freedom of the disordered C H3N H3 + molecules are reduced when the sample is cooled. This energy splitting drastically increases during an extended phase-transition coexistence region that persists from 160 to 120 K, becoming more pronounced in the orthorhombic phase. By tracking the temperature-dependent optical transition energies and using symmetry analysis that describes the evolution of electronic states from the tetragonal phase to the orthorhombic phase, we assign this energy splitting to the nearly degenerate transitions in the tetragonal phase from both the R - and M -point-derived states. Importantly, these assignments explain how momentum conservation effects lead to long hot-carrier lifetimes in the room-temperature tetragonal phase, with faster hot-carrier relaxation when the hybrid perovskite structurally transitions to the orthorhombic phase due to enhanced scattering at the Γ point.

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.

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

The chromosomal constitution of fish hybrid lineage revealed by 5S rDNA FISH.

Science.gov (United States)

Zhang, Chun; Ye, Lihai; Chen, Yiyi; Xiao, Jun; Wu, Yanhong; Tao, Min; Xiao, Yamei; Liu, Shaojun

2015-12-03

The establishment of the bisexual fertile fish hybrid lineage including the allodiploid and allotetraploid hybrids, from interspecific hybridization of red crucian carp (Carassius auratus red var. 2n = 100, 2n = AA) (♀) × common carp (Cyprinus carpio L. 2n = 100, 2n = BB) (♂), provided a good platform to investigate genetic relationship between the parents and their hybrid progenies. The chromosomal inheritance of diploid and allotetraploid hybrid progenies in successive generations, was studied by applying 5S rDNA fluorescence in situ hybridization. Signals of 5S rDNA distinguished the chromosomal constitution of common carp (B-genome) from red crucian carp (A-genome), in which two strong signals were observed on the first submetacentric chromosome, while no major signal was found in common carp. After fish hybridization, one strong signal of 5S rDNA was detected in the same locus on the chromosome of diploid hybrids. As expected, two strong signals were observed in 4nF3 tetraploid hybrids offspring and it is worth mentioning that two strong signals were detected in a separating bivalent of a primary spermatocyte in 4nF3. Furthermore, the mitosis of heterozygous chromosomes was shown normal and stable with blastular tissue histological studies. We revealed that 5S rDNA signal can be applied to discern A-genome from B-genome, and that 5S rDNA bearing chromosomes can be stably passed down in successive generations. Our work provided a significant method in fish breeding and this is important for studies in fish evolutionary biology.

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

Hybridized electromagnetic-triboelectric nanogenerator for scavenging biomechanical energy for sustainably powering wearable electronics.

Science.gov (United States)

Zhang, Kewei; Wang, Xue; Yang, Ya; Wang, Zhong Lin

2015-01-01

We report a hybridized electromagnetic-triboelectric nanogenerator for highly efficient scavenging of biomechanical energy to sustainably power wearable electronics by human walking. Based on the effective conjunction of triboelectrification and electromagnetic induction, the hybridized nanogenerator, with dimensions of 5 cm × 5 cm × 2.5 cm and a light weight of 60 g, integrates a triboelectric nanogenerator (TENG) that can deliver a peak output power of 4.9 mW under a loading resistance of 6 MΩ and an electromagnetic generator (EMG) that can deliver a peak output power of 3.5 mW under a loading resistance of 2 kΩ. The hybridized nanogenerator exhibits a good stability for the output performance and a much better charging performance than that of an individual energy-harvesting unit (TENG or EMG). Furthermore, the hybridized nanogenerator integrated in a commercial shoe has been utilized to harvest biomechanical energy induced by human walking to directly light up tens of light-emitting diodes in the shoe and sustainably power a smart pedometer for reading the data of a walking step, distance, and energy consumption. A wireless pedometer driven by the hybrid nanogenerator can work well to send the walking data to an iPhone under the distance of 25 m. This work pushes forward a significant step toward energy harvesting from human walking and its potential applications in sustainably powering wearable electronics.

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.

Inheritance patterns of enzymes and serum proteins of mallard-black duck hybrids

Science.gov (United States)

Morgan, R.P.; Meritt, D.W.; Block, S.B.; Cole, M.A.; Sulkin, S.T.; Lee, F.B.; Henny, C.J.

1984-01-01

From 1974 to 1976, a breeding program was used to produce hybrids of black ducks and mallards for the evaluation of inheritance patterns of serum proteins and serum, liver and muscle enzymes. In addition to the crosses designed to produce hybrids, a series of matings in 1975 and 1976 were designed to evaluate inheritance patterns of a hybrid with either a black duck or mallard. At the F1 level, hybrids were easily distinguished using serum proteins. However, once a hybrid was crossed back to either a mallard or black duck, only 12?23% of the progeny were distinguishable from black ducks or mallards using serum proteins and 23?39% using esterases. Muscle, serum and liver enzymes were similar between the two species.

Electron transport limitation in P3HT:CdSe nanorods hybrid solar cells.

Science.gov (United States)

Lek, Jun Yan; Xing, Guichuan; Sum, Tze Chien; Lam, Yeng Ming

2014-01-22

Hybrid solar cells have the potential to be efficient solar-energy-harvesting devices that can combine the benefits of solution-processable organic materials and the extended absorption offered by inorganic materials. In this work, an understanding of the factors limiting the performance of hybrid solar cells is explored. Through photovoltaic-device characterization correlated with transient absorption spectroscopy measurements, it was found that the interfacial charge transfer between the organic (P3HT) and inorganic (CdSe nanorods) components is not the factor limiting the performance of these solar cells. The insulating original ligands retard the charge recombination between the charge-transfer states across the CdSe-P3HT interface, and this is actually beneficial for charge collection. These cells are, in fact, limited by the subsequent electron collection via CdSe nanoparticles to the electrodes. Hence, the design of a more continuous electron-transport pathway should greatly improve the performance of hybrid solar cells in the future.

On the interaction between radon progeny and particles generated by electronic and traditional cigarettes

Science.gov (United States)

Vargas Trassierra, C.; Cardellini, F.; Buonanno, G.; De Felice, P.

2015-04-01

During their entire lives, people are exposed to the pollutants present in indoor air. Recently, Electronic Nicotine Delivery Systems, mainly known as electronic cigarettes, have been widely commercialized: they deliver particles into the lungs of the users but a "second-hand smoke" has yet to be associated to this indoor source. On the other hand, the naturally-occurring radioactive gas, i.e. radon, represents a significant risk for lung cancer, and the cumulative action of these two agents could be worse than the agents separately would. In order to deepen the interaction between radon progeny and second-hand aerosol from different types of cigarettes, a designed experimental study was carried out by generating aerosol from e-cigarette vaping as well as from second-hand traditional smoke inside a walk-in radon chamber at the National Institute of Ionizing Radiation Metrology (INMRI) of Italy. In this chamber, the radon present in air comes naturally from the floor and ambient conditions are controlled. To characterize the sidestream smoke emitted by cigarettes, condensation particle counters and scanning mobility particle sizer were used. Radon concentration in the air was measured through an Alphaguard ionization chamber, whereas the measurement of radon decay product in the air was performed with the Tracelab BWLM Plus-2S Radon daughter Monitor. It was found an increase of the Potential Alpha-Energy Concentration (PAEC) due to the radon decay products attached to aerosol for higher particle number concentrations. This varied from 7.47 ± 0.34 MeV L-1 to 12.6 ± 0.26 MeV L-1 (69%) for the e-cigarette. In the case of traditional cigarette and at the same radon concentration, the increase was from 14.1 ± 0.43 MeV L-1 to 18.6 ± 0.19 MeV L-1 (31%). The equilibrium factor increases, varying from 23.4% ± 1.11% to 29.5% ± 0.26% and from 30.9% ± 1.0% to 38.1 ± 0.88 for the e-cigarette and traditional cigarette, respectively. These growths still continue for long

Superhard sp{sup 2}–sp{sup 3} hybrid carbon allotropes with tunable electronic properties

Energy Technology Data Exchange (ETDEWEB)

Hu, Meng; Ma, Mengdong; Zhao, Zhisheng; Yu, Dongli; He, Julong, E-mail: hjl@ysu.edu.cn [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China)

2016-05-15

Four sp{sup 2}–sp{sup 3} hybrid carbon allotropes are proposed on the basis of first principles calculations. These four carbon allotropes are energetically more favorable than graphite under suitable pressure conditions. They can be assembled from graphite through intralayer wrinkling and interlayer buckling, which is similar to the formation of diamond from graphite. For one of the sp{sup 2}–sp{sup 3} hybrid carbon allotropes, mC24, the electron diffraction patterns match these of i-carbon, which is synthesized from shock-compressed graphite (H. Hirai and K. Kondo, Science, 1991, 253, 772). The allotropes exhibit tunable electronic characteristics from metallic to semiconductive with band gaps comparable to those of silicon allotropes. They are all superhard materials with Vickers hardness values comparable to that of cubic BN. The sp{sup 2}–sp{sup 3} hybrid carbon allotroes are promising materials for photovoltaic electronic devices, and abrasive and grinding tools.

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

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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.

Electron Landau damping of lower hybrid waves from a finite length antenna

International Nuclear Information System (INIS)

Brambilla, M.

1977-01-01

Launching and propagation of Lower Hybrid Waves to heat large plasmas by Electron Landau Damping is discussed. Conditions on the appropriate frequency and on the antenna location in the plasma density profile are derived

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.

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

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.

Inheritance and effectiveness of two transgenes determining PVY resistance in progeny from crossing independently transformed tobacco lines.

Science.gov (United States)

Czubacka, Anna; Sacco, Ermanno; Olszak-Przybyś, Hanna; Doroszewska, Teresa

2017-05-01

Genetic transformation of plants allows us to obtain improved genotypes enriched with the desired traits. However, if transgenic lines were to be used in breeding programs the stability of inserted transgenes is essential. In the present study, we followed the inheritance of transgenes in hybrids originated from crossing two transgenic tobacco lines resistant to Potato virus Y (PVY): MN 944 LMV with the transgene containing Lettuce mosaic virus coat protein gene (LMV CP) and AC Gayed ROKY2 with PVY replicase gene (ROKY2). Progeny populations generated by successive self-pollination were analyzed with respect to the transgene segregation ratio and resistance to Potato virus Y in tests carried out under greenhouse conditions. The presence of the virus in inoculated plants was detected by DAS-ELISA method. The results demonstrated the Mendelian fashion of inheritance of transgenes which were segregated independently and stably. As a result, we obtained T 4 generation of hybrid with both transgenes stacked and which was highly resistant to PVY.

Inorganic-organic hybrid polymer for preparation of affiliating material using electron beam irradiation

International Nuclear Information System (INIS)

Chung, Jaeseung; Kim, Seongeun; Kim, Byounggak; Lee, Jongchan; Park, Jihyun; Lee, Byeongcheol

2011-01-01

Recently, silver nano materials have gained a lot of attentions in a variety of applications due to the unique biological, optical, and electrical properties. Especially, the antifouling property of these material is considered to be an important character for biomedical field, marine coatings industry, biosensor, and drug delivery. In this study, we design and synthesize the inorganic-organic hybrid polymer for preparation of affiliating materials. Silver nano materials having antifouling property with different shapes are prepared by control the electron beam irradiation conditions. Inorganic-organic hybrid polymer was synthesized and characterized. → Morphology and size controlled nano materials are prepared using electron beam irradiation. → Silver nano materials having various shapes can be used for antifouling material

Hybrid quantum circuit with a superconducting qubit coupled to an electron spin ensemble

Energy Technology Data Exchange (ETDEWEB)

Kubo, Yuimaru; Grezes, Cecile; Vion, Denis; Esteve, Daniel; Bertet, Patrice [Quantronics Group, SPEC (CNRS URA 2464), CEA-Saclay, 91191 Gif-sur-Yvette (France); Diniz, Igor; Auffeves, Alexia [Institut Neel, CNRS, BP 166, 38042 Grenoble (France); Isoya, Jun-ichi [Research Center for Knowledge Communities, University of Tsukuba, 305-8550 Tsukuba (Japan); Jacques, Vincent; Dreau, Anais; Roch, Jean-Francois [LPQM (CNRS, UMR 8537), Ecole Normale Superieure de Cachan, 94235 Cachan (France)

2013-07-01

We report the experimental realization of a hybrid quantum circuit combining a superconducting qubit and an ensemble of electronic spins. The qubit, of the transmon type, is coherently coupled to the spin ensemble consisting of nitrogen-vacancy (NV) centers in a diamond crystal via a frequency-tunable superconducting resonator acting as a quantum bus. Using this circuit, we prepare arbitrary superpositions of the qubit states that we store into collective excitations of the spin ensemble and retrieve back into the qubit. We also report a new method for detecting the magnetic resonance of electronic spins at low temperature with a qubit using the hybrid quantum circuit, as well as our recent progress on spin echo experiments.

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

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.

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

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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.

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

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

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

Multifaceted, cross-generational costs of hybridization in sibling Drosophila species.

Directory of Open Access Journals (Sweden)

Erin M Myers

Full Text Available Maladaptive hybridization, as determined by the pattern and intensity of selection against hybrid individuals, is an important factor contributing to the evolution of prezygotic reproductive isolation. To identify the consequences of hybridization between Drosophila pseudoobscura and D. persimilis, we estimated multiple fitness components for F1 hybrids and backcross progeny and used these to compare the relative fitness of parental species and their hybrids across two generations. We document many sources of intrinsic (developmental and extrinsic (ecological selection that dramatically increase the fitness costs of hybridization beyond the well-documented F1 male sterility in this model system. Our results indicate that the cost of hybridization accrues over multiple generations and reinforcement in this system is driven by selection against hybridization above and beyond the cost of hybrid male sterility; we estimate a fitness loss of >95% relative to the parental species across two generations of hybridization. Our findings demonstrate the importance of estimating hybridization costs using multiple fitness measures from multiple generations in an ecologically relevant context; so doing can reveal intense postzygotic selection against hybridization and thus, an enhanced role for reinforcement in the evolution of populations and diversification of species.

Multifaceted, cross-generational costs of hybridization in sibling Drosophila species.

Science.gov (United States)

Myers, Erin M; Harwell, Tiffany I; Yale, Elizabeth L; Lamb, Abigail M; Frankino, W Anthony

2013-01-01

Maladaptive hybridization, as determined by the pattern and intensity of selection against hybrid individuals, is an important factor contributing to the evolution of prezygotic reproductive isolation. To identify the consequences of hybridization between Drosophila pseudoobscura and D. persimilis, we estimated multiple fitness components for F1 hybrids and backcross progeny and used these to compare the relative fitness of parental species and their hybrids across two generations. We document many sources of intrinsic (developmental) and extrinsic (ecological) selection that dramatically increase the fitness costs of hybridization beyond the well-documented F1 male sterility in this model system. Our results indicate that the cost of hybridization accrues over multiple generations and reinforcement in this system is driven by selection against hybridization above and beyond the cost of hybrid male sterility; we estimate a fitness loss of >95% relative to the parental species across two generations of hybridization. Our findings demonstrate the importance of estimating hybridization costs using multiple fitness measures from multiple generations in an ecologically relevant context; so doing can reveal intense postzygotic selection against hybridization and thus, an enhanced role for reinforcement in the evolution of populations and diversification of species.

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

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

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)

Paired-pulse facilitation achieved in protonic/electronic hybrid indium gallium zinc oxide synaptic transistors

Energy Technology Data Exchange (ETDEWEB)

Guo, Li Qiang, E-mail: guoliqiang@ujs.edu.cn; Ding, Jian Ning; Huang, Yu Kai [Micro/Nano Science & Technology Center, Jiangsu University, Zhenjiang, 212013 (China); Zhu, Li Qiang, E-mail: lqzhu@nimte.ac.cn [Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China)

2015-08-15

Neuromorphic devices with paired pulse facilitation emulating that of biological synapses are the key to develop artificial neural networks. Here, phosphorus-doped nanogranular SiO{sub 2} electrolyte is used as gate dielectric for protonic/electronic hybrid indium gallium zinc oxide (IGZO) synaptic transistor. In such synaptic transistors, protons within the SiO{sub 2} electrolyte are deemed as neurotransmitters of biological synapses. Paired-pulse facilitation (PPF) behaviors for the analogous information were mimicked. The temperature dependent PPF behaviors were also investigated systematically. The results indicate that the protonic/electronic hybrid IGZO synaptic transistors would be promising candidates for inorganic synapses in artificial neural network applications.

Paired-pulse facilitation achieved in protonic/electronic hybrid indium gallium zinc oxide synaptic transistors

Directory of Open Access Journals (Sweden)

Li Qiang Guo

2015-08-01

Full Text Available Neuromorphic devices with paired pulse facilitation emulating that of biological synapses are the key to develop artificial neural networks. Here, phosphorus-doped nanogranular SiO2 electrolyte is used as gate dielectric for protonic/electronic hybrid indium gallium zinc oxide (IGZO synaptic transistor. In such synaptic transistors, protons within the SiO2 electrolyte are deemed as neurotransmitters of biological synapses. Paired-pulse facilitation (PPF behaviors for the analogous information were mimicked. The temperature dependent PPF behaviors were also investigated systematically. The results indicate that the protonic/electronic hybrid IGZO synaptic transistors would be promising candidates for inorganic synapses in artificial neural network applications.

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).

Effects of aerosol polydispersity on theoretical calculations of unattached fractions of radon progeny

International Nuclear Information System (INIS)

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

1987-01-01

Theoretical calculations of unattached fractions of radon progeny require prediction of an attachment coefficient. Average attachment coefficients for aerosols of various count median diameters, CMD, and geometric standard deviations, σ/sub g/, are calculated using four different theories. These theories are: (1) the kinetic theory, (2) the diffusion theory, (3) the hybrid theory and (4) the kinetic-diffusion theory. Comparisons of the various calculated attachment coefficients are made and the implications of using either the kinetic or the diffusion theory to calculate unattached fractions for aerosols of various CMD and σg are discussed. Significant errors may arise in use of either the kinetic theory or the diffusion theory. Large and unacceptable errors arise in calculating unattached fractions of a polydisperse aerosol by characterizing the aerosol as monodisperse. Unattached fractions of RaA are calculated for two mine aerosols and a room aerosol

Alteration of the genomic composition of Solanum nigrum (+) potato backcross derivatives by somatic hybridisation: selection of fusion hybrids by DNA measurements and GISH

NARCIS (Netherlands)

Horsman, K.; Gavrilenko, T.; Bergervoet, M.; Huigen, D.J.; Tjin Wong Joe, A.; Jacobsen, E.

2001-01-01

Fusion experiments were performed with a first (BC1-6738) and a second (BC2-9017) generation backcross hybrid of 6x Solanum nigrum (+) 2x potato somatic hybrids with potato cultivars. Because no progeny was obtained from the BC2 genotypes, alternative approaches were sought to overcome the sexual

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

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

Excitation of lower hybrid waves by electron beams in finite geometry plasmas

International Nuclear Information System (INIS)

Gagne, R.R.J.; Shoucri, M.M.

1978-01-01

The dispersion relations for the quasi-static lower hybrid surface waves are derived. Conditions for their existence and their linear excitation by a small density electron beam are discussed. Instabilities appearing in low-frequency surface waves are also discussed. (author)

Electron and ion heat transport with lower hybrid current drive and neutral beam injection heating in ASDEX

International Nuclear Information System (INIS)

Soeldner, F.X.; Pereverzev, G.V.; Bartiromo, R.; Fahrbach, H.U.; Leuterer, F.; Murmann, H.D.; Staebler, A.; Steuer, K.H.

1993-01-01

Transport code calculations were made for experiments with the combined operation of lower hybrid current drive and heating and of neutral beam injection heating on ASDEX. Peaking or flattening of the electron temperature profile are mainly explained by modifications of the MHD induced electron heat transport. They originate from current profile changes due to lower hybrid and neutral beam current drive and to contributions from the bootstrap current. Ion heat transport cannot be described by one single model for all heating scenarios. The ion heat conductivity is reduced during lower hybrid heated phases with respect to Ohmic and neutral beam heating. (author). 13 refs, 5 figs

Genetic characterization and fine mapping of S25, a hybrid male sterility gene, on rice chromosome 12.

Science.gov (United States)

Kubo, Takahiko; Yoshimura, Atsushi; Kurata, Nori

2018-02-10

Hybrid male sterility genes are important factors in creating postzygotic reproductive isolation barriers in plants. One such gene, S25, is known to cause severe transmission ratio distortion in inter-subspecific progeny of cultivated rice Oryza sativa ssp. indica and japonica. To further characterize the S25 gene, we fine-mapped and genetically characterized the S25 gene using near-isogenic lines with reciprocal genetic backgrounds. We mapped the S25 locus within the 0.67-1.02 Mb region on rice chromosome 12. Further genetic analyses revealed that S25 substantially reduced male fertility in the japonica background, but not in the indica background. In first-generation hybrid progeny, S25 had a milder effect than it had in the japonica background. These results suggest that the expression of S25 is epistatically regulated by at least one partially dominant gene present in the indica genome. This finding supports our previous studies showing that hybrid male sterility due to pollen killer genes results from epistatic interaction with other genes that are hidden in the genetic background.

Unexpected ancestry of Populus seedlings from a hybrid zone implies a large role for postzygotic selection in the maintenance of species.

Science.gov (United States)

Lindtke, Dorothea; Gompert, Zachariah; Lexer, Christian; Buerkle, C Alex

2014-09-01

In the context of potential interspecific gene flow, the integrity of species will be maintained by reproductive barriers that reduce genetic exchange, including traits associated with prezygotic isolation or poor performance of hybrids. Hybrid zones can be used to study the importance of different reproductive barriers, particularly when both parental species and hybrids occur in close spatial proximity. We investigated the importance of barriers to gene flow that act early vs. late in the life cycle of European Populus by quantifying the prevalence of homospecific and hybrid matings within a mosaic hybrid zone. We obtained genotypic data for 11 976 loci from progeny and their maternal parents and constructed a Bayesian model to estimate individual admixture proportions and hybrid classes for sampled trees and for the unsampled pollen parent. Matings that included one or two hybrid parents were common, resulting in admixture proportions of progeny that spanned the whole range of potential ancestries between the two parental species. This result contrasts strongly with the distribution of admixture proportions in adult trees, where intermediate hybrids and each of the parental species are separated into three discrete ancestry clusters. The existence of the full range of hybrids in seedlings is consistent with weak reproductive isolation early in the life cycle of Populus. Instead, a considerable amount of selection must take place between the seedling stage and maturity to remove many hybrid seedlings. Our results highlight that high hybridization rates and appreciable hybrid fitness do not necessarily conflict with the maintenance of species integrity. © 2014 John Wiley & Sons Ltd.

Pressure dependence of electron density distribution and d-p-π hybridization in titanate perovskite ferroelectrics

Science.gov (United States)

Yamanaka, Takamitsu; Nakamoto, Yuki; Ahart, Muhtar; Mao, Ho-kwang

2018-04-01

Electron density distributions of PbTi O3 , BaTi O3 , and SrTi O3 were determined by synchrotron x-ray powder diffraction up to 55 GPa at 300 K and ab initio quantum chemical molecular orbital (MO) calculations, together with a combination of maximum entropy method calculations. The intensity profiles of Bragg peaks reveal split atoms in both ferroelectric PbTi O3 and BaTi O3 , reflecting the two possible positions occupied by the Ti atom. The experimentally obtained atomic structure factor was used for the determination of the deformation in electron density and the d-p-π hybridization between dx z (and dy z) of Ti and px (and py) of O in the Ti-O bond. Ab initio MO calculations proved the change of the molecular orbital coupling and of Mulliken charges with a structure transformation. The Mulliken charge of Ti in the Ti O6 octahedron increased in the ionicity with increasing pressure in the cubic phase. The bonding nature is changed with a decrease in the hybridization of the Ti-O bond and the localization of the electron density with increasing pressure. The hybridization decreases with pressure and disappears in the cubic paraelectric phase, which has a much more localized electron density distribution.

Universal logic gates via liquid-electronic hybrid divider

KAUST Repository

Zhou, Bingpu

2012-01-01

We demonstrated two-input microdroplet-based universal logic gates using a liquid-electronic hybrid divider. All 16 Boolean logic functions have been realized by manipulating the applied voltages. The novel platform consists of a microfluidic chip with integrated microdroplet detectors and external electronic components. The microdroplet detectors act as the communication media for fluidic and electronic information exchange. The presence or absence of microdroplets at the detector translates into the binary signal 1 or 0. The embedded micro-mechanical pneumatically actuated valve (PAV), fabricated using the well-developed multilayer soft lithography technique, offers biocompatibility, flexibility and accuracy for the on-chip realization of different logic functions. The microfluidic chip can be scaled up to construct large-scale microfluidic logic computation. On the other hand, the microfluidic chip with a specific logic function can be applied to droplet-based chemical reactions for on-demand bio or chemical analysis. Our experimental results have presented an autonomously driven, precision-controlled microfluidic chip for chemical reactions based on the IF logic function. © 2012 The Royal Society of Chemistry.

Assignment of electron transfer flavoprotein-ubiquinone oxidoreductase (ETF-QO) to human chromosome 4q33 by fluorescence in situ hybridization and somatic cell hybridization.

Science.gov (United States)

Spector, E B; Seltzer, W K; Goodman, S I

1999-08-01

Electron transfer flavoprotein-ubiquinone oxidoreductase (ETF-QO) is a nuclear-encoded protein located in the inner mitochondrial membrane. Inherited defects of ETF-QO cause glutaric acidemia type II. We here describe the localization of the ETF-QO gene to human chromosome 4q33 by somatic cell hybridization and fluorescence in situ hybridization. Copyright 1999 Academic Press.

Comparison of the decomposition characteristics of aromatic VOCs using an electron beam hybrid system

International Nuclear Information System (INIS)

Son, Youn-Suk; Kim, Ki-Joon; Kim, Ji-Yong; Kim, Jo-Chun

2010-01-01

We applied a hybrid technique to assess the decomposition characteristics of ethylbenzene and toluene that annexed the catalyst technique with existing electron beam (EB) technology. The removal efficiency of ethylbenzene in the EB-catalyst hybrid turned out to be 30% greater than that of EB-only treatment. We concluded that ethylbenzene was decomposed more easily than toluene by EB irradiation. We compared the independent effects of the EB-catalyst hybrid and catalyst-only methods, and observed that the efficiency of the EB-catalyst hybrid demonstrated approximately 6% improvement for decomposing toluene and 20% improvement for decomposing ethylbenzene. The G-values for ethylbenzene increased with initial concentration and reactor type: for example, the G-values by reactor type at 2800 ppmC were 7.5-10.9 (EB-only) and 12.9-25.7 (EB-catalyst hybrid). We also observed a significant decrease in by-products as well as in the removal efficiencies associated with the EB-catalyst hybrid technique.

Comparison of the decomposition characteristics of aromatic VOCs using an electron beam hybrid system

Science.gov (United States)

Son, Youn-Suk; Kim, Ki-Joon; Kim, Ji-Yong; Kim, Jo-Chun

2010-12-01

We applied a hybrid technique to assess the decomposition characteristics of ethylbenzene and toluene that annexed the catalyst technique with existing electron beam (EB) technology. The removal efficiency of ethylbenzene in the EB-catalyst hybrid turned out to be 30% greater than that of EB-only treatment. We concluded that ethylbenzene was decomposed more easily than toluene by EB irradiation. We compared the independent effects of the EB-catalyst hybrid and catalyst-only methods, and observed that the efficiency of the EB-catalyst hybrid demonstrated approximately 6% improvement for decomposing toluene and 20% improvement for decomposing ethylbenzene. The G-values for ethylbenzene increased with initial concentration and reactor type: for example, the G-values by reactor type at 2800 ppmC were 7.5-10.9 (EB-only) and 12.9-25.7 (EB-catalyst hybrid). We also observed a significant decrease in by-products as well as in the removal efficiencies associated with the EB-catalyst hybrid technique.

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

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

Electron imaging with Medipix2 hybrid pixel detector

International Nuclear Information System (INIS)

McMullan, G.; Cattermole, D.M.; Chen, S.; Henderson, R.; Llopart, X.; Summerfield, C.; Tlustos, L.; Faruqi, A.R.

2007-01-01

The electron imaging performance of Medipix2 is described. Medipix2 is a hybrid pixel detector composed of two layers. It has a sensor layer and a layer of readout electronics, in which each 55 μmx55 μm pixel has upper and lower energy discrimination and MHz rate counting. The sensor layer consists of a 300 μm slab of pixellated monolithic silicon and this is bonded to the readout chip. Experimental measurement of the detective quantum efficiency, DQE(0) at 120 keV shows that it can reach ∼85% independent of electron exposure, since the detector has zero noise, and the DQE(Nyquist) can reach ∼35% of that expected for a perfect detector (4/π 2 ). Experimental measurement of the modulation transfer function (MTF) at Nyquist resolution for 120 keV electrons using a 60 keV lower energy threshold, yields a value that is 50% of that expected for a perfect detector (2/π). Finally, Monte Carlo simulations of electron tracks and energy deposited in adjacent pixels have been performed and used to calculate expected values for the MTF and DQE as a function of the threshold energy. The good agreement between theory and experiment allows suggestions for further improvements to be made with confidence. The present detector is already very useful for experiments that require a high DQE at very low doses

Electron imaging with Medipix2 hybrid pixel detector.

Science.gov (United States)

McMullan, G; Cattermole, D M; Chen, S; Henderson, R; Llopart, X; Summerfield, C; Tlustos, L; Faruqi, A R

2007-01-01

The electron imaging performance of Medipix2 is described. Medipix2 is a hybrid pixel detector composed of two layers. It has a sensor layer and a layer of readout electronics, in which each 55 microm x 55 microm pixel has upper and lower energy discrimination and MHz rate counting. The sensor layer consists of a 300 microm slab of pixellated monolithic silicon and this is bonded to the readout chip. Experimental measurement of the detective quantum efficiency, DQE(0) at 120 keV shows that it can reach approximately 85% independent of electron exposure, since the detector has zero noise, and the DQE(Nyquist) can reach approximately 35% of that expected for a perfect detector (4/pi(2)). Experimental measurement of the modulation transfer function (MTF) at Nyquist resolution for 120 keV electrons using a 60 keV lower energy threshold, yields a value that is 50% of that expected for a perfect detector (2/pi). Finally, Monte Carlo simulations of electron tracks and energy deposited in adjacent pixels have been performed and used to calculate expected values for the MTF and DQE as a function of the threshold energy. The good agreement between theory and experiment allows suggestions for further improvements to be made with confidence. The present detector is already very useful for experiments that require a high DQE at very low doses.

Isolation and molecular cytogenetic characterization of a wheat - Leymus mollis double monosomic addition line and its progenies with resistance to stripe rust.

Science.gov (United States)

Yang, Xiaofei; Li, Xin; Wang, Changyou; Chen, Chunhuan; Tian, Zengrong; Ji, Wanquan

2017-12-01

A common wheat - Leymus mollis (2n = 4x = 28, NsNsXmXm) double monosomic addition line, M11003-4-3-8/13/15 (2n = 44 = 42T.a + L.m2 + L.m3), with stripe rust resistance was developed (where T.a represents Triticum aestivum chromosome, L.m represents L. mollis chromosome, and L.m2/3 represents L. mollis chromosome of homoeologous groups 2 and 3). The progenies of line M11003-4-3-8/13/15 were characterized by cytological observation, specific molecular markers, fluorescence in situ hybridization (FISH), and genomic in situ hybridization (GISH). Among the progenies, there existed five different types (I, II, III, IV, and V) of chromosome constitution, the formulas of which were 2n = 44 = 42T.a + 1L.m2 + 1L.m3, 2n = 43 = 42T.a + 1L.m2, 2n = 43 = 42T.a + 1L.m3, 2n = 42 = 42T.a, and 2n = 44 = 42T.a + 2L.m2, respectively. Field disease screening showed that types I and III showed high resistance to stripe rust, while types II, IV, and V were susceptible. Leymus mollis was almost immune to stripe rust, whereas the wheat parent, cultivar 7182, was susceptible. Therefore, we concluded that the stripe rust resistance originated from L. mollis. These various lines could be further fully exploited as important disease resistance materials to enrich wheat genetic resources.

Ag–graphene hybrid conductive ink for writing electronics

International Nuclear Information System (INIS)

Xu, L Y; Yang, G Y; Jing, H Y; Han, Y D; Wei, J

2014-01-01

With the aim of preparing a method for the writing of electronics on paper by the use of common commercial rollerball pens loaded with conductive ink, hybrid conductive ink composed of Ag nanoparticles (15 wt%) and graphene–Ag composite nanosheets (0.15 wt%) formed by depositing Ag nanoparticles (∼10 nm) onto graphene sheets was prepared for the first time. Owing to the electrical pathway effect of graphene and the decreased contact resistance of graphene junctions by depositing Ag nanoparticles (NPs) onto graphene sheets, the concentration of Ag NPs was significantly reduced while maintaining high conductivity at a curing temperature of 100 ° C. A typical resistivity value measured was 1.9 × 10 −7  Ω m, which is 12 times the value for bulk silver. Even over thousands of bending cycles or rolling, the resistance values of writing tracks only increase slightly. The stability and flexibility of the writing circuits are good, demonstrating the promising future of this hybrid ink and direct writing method. (paper)

DEVELOPMENT AND COMPREHENSIVE ASSESSMENT OF BULBOUS FORMS OF INTERSPECIFIC HYBRIDS OF ONION ALLIUM CEPA x A. FISTULOSUM

Directory of Open Access Journals (Sweden)

V. S. Romanov

2016-01-01

Full Text Available One of the way of increasing of genetic variability of onion (Allium cepa L. is the interspecific hybridization. Development of onion interspecific hybrids consists of the study of initial breeding forms, its heterogeneity, ways of crossing and pollination, overcoming of outbreeding problem, sterility and weak fertility of the hybrids of first and next generations, specifics of hybrid’s seeds development, identification and selection of recombinant forms with breeding valuable traits. The stages of development of the bulbous forms of interspecific hybrids of onion are presented in the article. The study was conducted in the “All-Russian Scientific Research Institute of vegetable breeding and seed production” of the Moscow region. The plants of inbreed progenies I1-5 from BC1-2F5 of bulb forms of interspecific hybrids A. cepa х A. Fistulosum as well as the parental forms were analyzed. The breeding and phytopathological assessment of recombinant forms of onion interspecific hybrids was done for qualitative and quantitative traits and for resistance to downy mildew. Using the individual selection for quality and quantity traits, it was found that the forms, whose traits were not undergo the inbreeding depression because of the higher homozygosity can be used for development of linear initial material for breeding for heterosis. The forms with the inbreeding depression have to be used for crossbreeding. Along with increasing of homozygosity, the new modified genotypes appear because of potential variability and genes recombination. It allows to make the purposive selection of recombinant forms for valuable traits. The selected onion forms from inbreed progenies of I1-5 from BC1-2F5 which have bulbs of flat and well-rounded-flat shape are characterized by high resistance to downy mildew and bulbs with good storage ability. The selection process of the recombinant forms from progenies of onion interspecific hybrids obtained based on repeated

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.

A comprehensive overview of hybrid electric vehicle: Powertrain configurations, powertrain control techniques and electronic control units

Energy Technology Data Exchange (ETDEWEB)

Cagatay Bayindir, Kamil; Goezuekuecuek, Mehmet Ali; Teke, Ahmet [Cukurova University, Department of Electrical and Electronics Engineering, Balcali, Saricam, Adana (Turkey)

2011-02-15

The studies for hybrid electrical vehicle (HEV) have attracted considerable attention because of the necessity of developing alternative methods to generate energy for vehicles due to limited fuel based energy, global warming and exhaust emission limits in the last century. HEV incorporates internal composition engine, electric machines and power electronic equipments. In this study, overview of HEVs with a focus on hybrid configurations, energy management strategies and electronic control units are presented. Advantages and disadvantages of each configuration are clearly emphasized. The existing powertrain control techniques for HEVs are classified and comprehensively described. Electronic control units used in HEV configuration are also elaborated. The latest trends and technological challenges in the near future for HEVs are discussed. (author)

ZnO nanostructures as electron extraction layers for hybrid perovskite thin films

Science.gov (United States)

Nikolaidou, Katerina; Sarang, Som; Tung, Vincent; Lu, Jennifer; Ghosh, Sayantani

Optimum interaction between light harvesting media and electron transport layers is critical for the efficient operation of photovoltaic devices. In this work, ZnO layers of different morphologies are implemented as electron extraction and transport layers for hybrid perovskite CH3NH3PbI3 thin films. These include nanowires, nanoparticles, and single crystalline film. Charge transfer at the ZnO/perovskite interface is investigated and compared through ultra-fast characterization techniques, including temperature and power dependent spectroscopy, and time-resolved photoluminescence. The nanowires cause an enhancement in perovskite emission, which may be attributed to increased scattering and grain boundary formation. However, the ZnO layers with decreasing surface roughness exhibit better electron extraction, as inferred from photoluminescence quenching, reduction in the number of bound excitons, and reduced exciton lifetime in CH3NH3PbI3 samples. This systematic study is expected to provide an understanding of the fundamental processes occurring at the ZnO-CH3NH3PbI3 interface and ultimately, provide guidelines for the ideal configuration of ZnO-based hybrid Perovskite devices. This research was supported by National Aeronautics and Space administration (NASA) Grant No: NNX15AQ01A.

Quantum teleportation and entanglement swapping of electron spins in superconducting hybrid structures

Energy Technology Data Exchange (ETDEWEB)

Bubanja, Vladimir, E-mail: vladimir.bubanja@callaghaninnovation.govt.nz

2015-06-15

We present schemes for quantum teleportation and entanglement swapping of electronic spin states in hybrid superconductor–normal-metal systems. The proposed schemes employ subgap transport whereby the lowest order processes involve Cooper pair-electron and double Cooper-pair cotunneling in quantum teleportation and entanglement swapping protocols, respectively. The competition between elastic cotunneling and Cooper-pair splitting results in the success probability of 25% in both cases. Described implementations of these protocols are within reach of present-day experimental techniques.

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

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

Embryogenic calli induced in interspecific (Elaeis guineensis x E. oleifera hybrid zygotic embryos

Directory of Open Access Journals (Sweden)

Paula Cristina da Silva Angelo

2009-01-01

Full Text Available The hybridization between oil palm (Elaeis guineensis and caiaué (E. oleifera plants is directed to obtainprogenies presenting high yields like oil palm but with reduced shoot height and resistance to lethal yellowing like caiaué.Cloning F1, BC1 and BC2 progenies can make the replication of selection trials easier. The objective of this work was to inducesomatic embryogenesis in interspecific zygotic embryos collected 100 days after pollination. Three progenies were cultivatedin an induction medium developed for Tenera (E. guineensis tp. dura x pisifera embryos. The number of embryos bearing calliand germinating was recorded and submitted to the Z test. Calli were weighted and submitted to histological analysis.Progenies differed in the number of embryos presenting plumules and calli simultaneously. By the ninth month, the apices ofincompletely developed somatic embryos were observed protruding from the surfaces of nodular calli. Highly embryogenicand friable secondary calli producing globular somatic embryos were not observed.

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)

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)

Existence of vigorous lineages of crop-wild hybrids in Lettuce under field conditions.

Science.gov (United States)

Hooftman, Danny A P; Hartman, Yorike; Oostermeijer, J Gerard B; Den Nijs, Hans J C M

2009-01-01

Plant to plant gene flow is a route of environmental exposure for GM plants specifically since crosses with wild relatives could lead to the formation of more vigorous hybrids, which could increase the rate of introgression and the environmental impact. Here, we test the first step in the process of potential transgene introgression: whether hybrid vigor can be inherited to the next generation, which could lead to fixation of altered, i.e., elevated, quantitative traits. The potential for a permanent elevated fitness was tested using individual autogamous progeny lineages of hybrids between the crop Lactuca sativa (Lettuce) and the wild species Lactuca serriola (Prickly Lettuce). We compared progeny from motherplants grown under either greenhouse or field conditions. The survival of young plants depended strongly on maternal environment. Furthermore, we observed that offspring reproductive fitness components were correlated with maternal fitness. Our study demonstrates that post-zygotic genotypic sorting at the young plants stage reduces the number of genotypes non-randomly, leading to inheritance of high levels of reproductive traits in the surviving hybrid lineages, compared to the pure wild relatives. Consequently, directional selection could lead to displacement of the pure wild relative and fixation of more vigorous genome segments originating from crops, stabilizing plant traits at elevated levels. Such information can be used to indentify segments which are less likely to introgress into wild relative populations as a target for transgene insertion. © ISBR, EDP Sciences, 2010.

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

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.

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.)

Self-powered textile for wearable electronics by hybridizing fiber-shaped nanogenerators, solar cells, and supercapacitors.

Science.gov (United States)

Wen, Zhen; Yeh, Min-Hsin; Guo, Hengyu; Wang, Jie; Zi, Yunlong; Xu, Weidong; Deng, Jianan; Zhu, Lei; Wang, Xin; Hu, Chenguo; Zhu, Liping; Sun, Xuhui; Wang, Zhong Lin

2016-10-01

Wearable electronics fabricated on lightweight and flexible substrate are believed to have great potential for portable devices, but their applications are limited by the life span of their batteries. We propose a hybridized self-charging power textile system with the aim of simultaneously collecting outdoor sunshine and random body motion energies and then storing them in an energy storage unit. Both of the harvested energies can be easily converted into electricity by using fiber-shaped dye-sensitized solar cells (for solar energy) and fiber-shaped triboelectric nanogenerators (for random body motion energy) and then further stored as chemical energy in fiber-shaped supercapacitors. Because of the all-fiber-shaped structure of the entire system, our proposed hybridized self-charging textile system can be easily woven into electronic textiles to fabricate smart clothes to sustainably operate mobile or wearable electronics.

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

Generation of suprathermal electrons during plasma current startup by lower hybrid waves in a tokamak

International Nuclear Information System (INIS)

Ohkubo, K.; Toi, K.; Kawahata, K.

1984-10-01

Suprathermal electrons which carry a seed current are generated by non-resonant parametric decay instability during initial phase of lower hybrid current startup in the JIPP T-IIU tokamak. From the numerical analysis, it is found that parametrically excited lower hybrid waves at lower side band can bridge the spectral gap between the thermal velocity and the low velocity end in the pump power spectrum. (author)

Cytogenetics and stripe rust resistance of wheat-Thinopyrum elongatum hybrid derivatives.

Science.gov (United States)

Li, Daiyan; Long, Dan; Li, Tinghui; Wu, Yanli; Wang, Yi; Zeng, Jian; Xu, Lili; Fan, Xing; Sha, Lina; Zhang, Haiqin; Zhou, Yonghong; Kang, Houyang

2018-01-01

Amphidiploids generated by distant hybridization are commonly used as genetic bridge to transfer desirable genes from wild wheat species into cultivated wheat. This method is typically used to enhance the resistance of wheat to biotic or abiotic stresses, and to increase crop yield and quality. Tetraploid Thinopyrum elongatum exhibits strong adaptability, resistance to stripe rust and Fusarium head blight, and tolerance to salt, drought, and cold. In the present study, we produced hybrid derivatives by crossing and backcrossing the Triticum durum-Th. elongatum partial amphidiploid ( Trititrigia 8801, 2 n  = 6 ×  = 42, AABBEE) with wheat cultivars common to the Sichuan Basin. By means of cytogenetic and disease resistance analyses, we identified progeny harboring alien chromosomes and measured their resistance to stripe rust. Hybrid progenies possessed chromosome numbers ranging from 40 to 47 (mean = 42.72), with 40.0% possessing 42 chromosomes. Genomic in situ hybridization revealed that the number of alien chromosomes ranged from 1 to 11. Out of the 50 of analyzed lines, five represented chromosome addition (2 n  = 44 = 42 W + 2E) and other five were chromosome substitution lines (2 n  = 42 = 40 W + 2E). Importantly, a single chromosome derived from wheat- Th. elongatum intergenomic Robertsonian translocations chromosome was occurred in 12 lines. Compared with the wheat parental cultivars ('CN16' and 'SM482'), the majority (70%) of the derivative lines were highly resistant to strains of stripe rust pathogen known to be prevalent in China. The findings suggest that these hybrid-derivative lines with stripe rust resistance could potentially be used as germplasm sources for further wheat improvement.

Development of aromatic VOC control technology by electron beam hybrid

International Nuclear Information System (INIS)

Kim, Jo-Chun; Kim, Ki-Joon

2006-01-01

As a fundamental study, the decomposition of volatile organic compounds (VOCs) using electron beam (EB) irradiation has been extensively investigated. EB treatments of VOCs such as toluene and styrene are discussed. The degradation characteristics were intensively investigated under various concentrations and irradiation doses to determine and improve VOC removal efficiencies. This work illustrates that the removal efficiencies of aromatic VOCs generally increase as their concentrations decrease and the irradiation doses increase. Based on these basic studies, it was found that by-products produced from EB irradiation of VOCs would cause a secondary pollution problem. Therefore, a novel hybrid technology has been applied to control aromatic VOC emissions by annexing the catalyst technique with conventional treatment study using EB technology. The experiments were carried out using a bench-scale at first, then a pilot-scale system was followed. Toluene was selected as a typical VOC for EB hybrid control to investigate by-products, effects of ceramic and catalyst, and factors affecting overall efficiency of degradation. It was concluded that VOCs could be destroyed more effectively by a novel hybrid system than single EB irradiation. (author)

Design and operation of an automated beta-particle counting system for the measurement of 220Rn (and 222Rn) progeny

International Nuclear Information System (INIS)

Bigu, J.

1992-01-01

A fully automated system of the continuous (active) type has been designed for the unattended quantification of 222 Rn progeny and 220 Rn progeny in calibration and test facilities, as well as working and living environments. The system uses a β-particle detector and associated electronic circuitry, in conjunction with an in-house microprocessor-based processing interface card and a personal computer, operated by specially developed in-house software. The system represents a significant improvement over systems using α-particle detectors because of its enhanced flexibility of design and virtual elimination of plate-out effects in the sampling head, and of self-absorption phenomena in the sampling filter. The β-particle system was tested and calibrated in a Radon and Thoron Test Facility of the walk-in type under a variety of experimental conditions. (author)

Generation and control of electronic hybrid entanglement via a two-dimensional Rashba anisotropic nanodot

Energy Technology Data Exchange (ETDEWEB)

Amiri, F.; Rastgoo, S.; Golshan, M.M., E-mail: golshan@susc.ac.ir

2014-06-13

In the present article we report the dynamics of electronic spin–subbands, as well as subband–subband, hybrid entanglements in a two-dimensional anisotropic quantum dot. The dot is under the influence of Rashba effect and an external magnetic field. To study the hybrid entanglements, we partition the system into two categories in which either spatial degrees of freedom, subbands, entangle with the spin or the subbands become entangled amongst themselves. For the first case we calculate the von Neumann entropy, while for the latter the negativity is calculated. Our calculations show that for both cases information is periodically distributed between the corresponding subspaces. Effects of Rashba parameter and magnetic field on the characteristics of such oscillatory behavior are also discussed. For spin–subband entanglement the oscillations include dips, surrounded by plateaus of maximal entanglement. The subband–subband entanglement shows vanishingly small plateaus. The duration of plateaus is controlled by Rashba coupling and the external field. - Highlights: • Dynamics of hybrid entanglements in a parabolic 2-dimensional electron gas is reported. • The electron gas is influenced by the Rashba spin–orbit coupling and a magnetic field. • Spin–subband entanglement exhibits oscillations with dips and maximal plateaus. • Subband–subband entanglement also oscillates, but with vanishingly small plateaus. • The vigilance of plateaus is controllable by the Rashba effect and/or the field.

Study of the fast electron distribution function in lower hybrid and electron cyclotron current driven plasmas in the WT-3 tokamak

International Nuclear Information System (INIS)

Ogura, K.; Tanaka, H.; Ide, S.

1991-01-01

The distribution function f(p-vector) of fast electrons produced by lower hybrid current drive (LHCD) is investigated in the WT-3 tokamak, using a combination of measurements of the hard X-ray (HXR) angular distribution with respect to the toroidal magnetic field and observations of the HXR radial profile. The data obtained indicate the formation of a plateau-like region in f(p-vector) which corresponds to a region of resonant interaction between the lower hybrid (LH) wave and the electrons. The energy of the fast electrons in the peripheral plasma region is observed to be higher than that in the central plasma region under operational conditions with a high plasma current (I p ≥ 80 kA). At low current (I p < or approx. 50 kA), however, the energy of fast electrons is constant along the plasma radius. In the current ramp-up phase, fast electrons are generated in the directions normal to and opposite to the LH wave propagation. The latter case is ascribed to a negatively biased toroidal electric field induced by the current ramp-up. To study the characteristic change of f(p-vector) for various current drive mechanisms, HXR measurements are performed in electron cyclotron current driven (ECCD) plasma and in Ohmic heating (OH) plasma. In ECCD plasma, the perpendicular energy of fast electrons increases, which indicates that fast electrons are accelerated perpendicularly by electron cyclotron heating. In both LHCD and ECCD plasmas, fast electrons flow in the direction opposite to the wave propagation, while no such fast electrons are formed in OH plasma. (author). 33 refs, 16 figs, 1 tab

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

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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.

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).

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

Early life traits of farm and wild Atlantic salmon Salmo salar and first generation hybrids in the south coast of Newfoundland.

Science.gov (United States)

Hamoutene, D; Perez-Casanova, J; Burt, K; Lush, L; Caines, J; Collier, C; Hinks, R

2017-06-01

This study examined fertilization rates, survival and early life-trait differences of pure farm, wild and first generation (F1) hybrid origin embryos after crossing farm and wild Atlantic salmon Salmo salar. Results show that despite a trend towards higher in vitro fertilization success for wild females, differences in fertilization success in river water are not significantly different among crosses. In a hatchery environment, wild females' progeny (pure wild and hybrids with wild maternal parent) hatched 7-11 days earlier than pure farm crosses and hybrids with farm maternal parents. In addition, pure wild progeny had higher total lengths (L T ) at hatch than pure farm crosses and hybrids. Directions in trait differences need to be tested in a river environment, but results clearly show the maternal influence on early stages beyond egg-size differences. Differences in L T were no longer significant at 70 days post hatch (shortly after the onset of exogenous feeding) showing the need to investigate later developmental stages to better assess somatic growth disparities due to genetic differences. Higher mortality rates of the most likely hybrids (farm female × wild male hybrids) at egg and fry stages and their delayed hatch suggest that these F1 hybrids might be less likely to survive the early larval stages than wild stocks. © 2017 Her Majesty the Queen in Right of Canada. Journal of Fish Biology © 2017 The Fisheries Society of the British Isles.

Complementary Self-Biased Logics Based on Single-Electron Transistor (SET)/CMOS Hybrid Process

Science.gov (United States)

Song, Ki-Whan; Lee, Yong Kyu; Sim, Jae Sung; Kim, Kyung Rok; Lee, Jong Duk; Park, Byung-Gook; You, Young Sub; Park, Joo-On; Jin, You Seung; Kim, Young-Wug

2005-04-01

We propose a complementary self-biasing method which enables the single-electron transistor (SET)/complementary metal-oxide semiconductor (CMOS) hybrid multi-valued logics (MVLs) to operate well at high temperatures, where the peak-to-valley current ratio (PVCR) of the Coulomb oscillation markedly decreases. The new architecture is implemented with a few transistors by utilizing the phase control capability of the sidewall depletion gates in dual-gate single-electron transistors (DGSETs). The suggested scheme is evaluated by a SPICE simulation with an analytical DGSET model. Furthermore, we have developed a new process technology for the SET/CMOS hybrid systems. We have confirmed that both of the fabricated devices, namely, SET and CMOS transistors, exhibit the ideal characteristics for the complementary self-biasing scheme: the SET shows clear Coulomb oscillations with a 100 mV period and the CMOS transistors show a high voltage gain.

Hybrid transport and diffusion modeling using electron thermal transport Monte Carlo SNB in DRACO

Science.gov (United States)

Chenhall, Jeffrey; Moses, Gregory

2017-10-01

The iSNB (implicit Schurtz Nicolai Busquet) multigroup diffusion electron thermal transport method is adapted into an Electron Thermal Transport Monte Carlo (ETTMC) transport method to better model angular and long mean free path non-local effects. Previously, the ETTMC model had been implemented in the 2D DRACO multiphysics code and found to produce consistent results with the iSNB method. Current work is focused on a hybridization of the computationally slower but higher fidelity ETTMC transport method with the computationally faster iSNB diffusion method in order to maximize computational efficiency. Furthermore, effects on the energy distribution of the heat flux divergence are studied. Work to date on the hybrid method will be presented. This work was supported by Sandia National Laboratories and the Univ. of Rochester Laboratory for Laser Energetics.

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

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

Hybrid male sterility between Drosophila willistoni species is caused by male failure to transfer sperm during copulation.

Science.gov (United States)

Civetta, Alberto; Gaudreau, Chelsea

2015-05-01

The biological concept of species stresses the importance of understanding what mechanisms maintain species reproductively isolated from each other. Often such mechanisms are divided into premating and postmating, with the latest being the result of either prezygotic or postzygotic isolation barriers. Drosophila willistoni quechua and Drosophila willistoni willistoni are two subspecies that experience reproductive isolation. When a D. w. quechua female is crossed with a D. w. willistoni male, the hybrid males (F1QW) are unable to father progeny; however, the reciprocal cross produces fertile hybrids. Thus, the mechanism of isolation is unidirectional hybrid male sterility. However, the sterile F1QW males contain large amounts of motile sperm. Here we explore whether pre-copulatory or post-copulatory pre-zygotic mechanisms serve as major deterrents in the ability of F1QW males to father progeny. Comparisons of parental and hybrid males copulation durations showed no significant reduction in copulation duration of F1QW males. Interrupted copulations of the parental species confirmed that sperm transfer occurs before the minimum copulation duration registered for F1QW males. However, we found that when females mate with F1QW males, sperm is not present inside the female storage organs and that the lack of sperm in storage is due to failure to transfer sperm rather than spillage or active sperm dumping by females. Sterility of F1QW hybrid males is primarily driven by their inability to transfer sperm during copulation.

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)

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.

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)

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.

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

The nature of excess electrons in anatase and rutile from hybrid DFT and RPA.

Science.gov (United States)

Spreafico, Clelia; VandeVondele, Joost

2014-12-21

The behavior of excess electrons in undoped and defect free bulk anatase and rutile TiO2 has been investigated by state-of-the-art electronic structure methods including hybrid density functional theory (DFT) and the random phase approximation (RPA). Consistent with experiment, charge trapping and polaron formation is observed in both anatase and rutile. The difference in the anisotropic shape of the polarons is characterized, confirming for anatase the large polaron picture. For anatase, where polaron formation energies are small, charge trapping is observed also with standard hybrid functionals, provided the simulation cell is sufficiently large (864 atoms) to accommodate the lattice relaxation. Even though hybrid orbitals are required as a starting point for RPA in this system, the obtained polaron formation energies are relatively insensitive to the amount of Hartree-Fock exchange employed. The difference in trapping energy between rutile and anatase can be obtained accurately with both hybrid functionals and RPA. Computed activation energies for polaron hopping and delocalization clearly show that anatase and rutile might have different charge transport mechanisms. In rutile, only hopping is likely, whereas in anatase hopping and delocalization are competing. Delocalization will result in conduction-band-like and thus enhanced transport. Anisotropic conduction, in agreement with experimental data, is observed, and results from the tendency to delocalize in the [001] direction in rutile and the (001) plane in anatase. For future work, our calculations serve as a benchmark and suggest RPA on top on hybrid orbitals (PBE0 with 30% Hartree-Fock exchange), as a suitable method to study the rich chemistry and physics of TiO2.

Hybrid (Vlasov-Fluid) simulation of ion-acoustic solitons chain formation including trapped electrons

Energy Technology Data Exchange (ETDEWEB)

Behjat, E.; Aminmansoor, F.; Abbasi, H. [Faculty of Energy Engineering and Physics, Amirkabir University of Technology, P. O. Box 15875-4413, Tehran (Iran, Islamic Republic of)

2015-08-15

Disintegration of a Gaussian profile into ion-acoustic solitons in the presence of trapped electrons [H. Hakimi Pajouh and H. Abbasi, Phys. Plasmas 15, 082105 (2008)] is revisited. Through a hybrid (Vlasov-Fluid) model, the restrictions associated with the simple modified Korteweg de-Vries (mKdV) model are studied. For instance, the lack of vital information in the phase space associated with the evolution of electron velocity distribution, the perturbative nature of mKdV model which limits it to the weak nonlinear cases, and the special spatio-temporal scaling based on which the mKdV is derived. Remarkable differences between the results of the two models lead us to conclude that the mKdV model can only monitor the general aspects of the dynamics, and the precise picture including the correct spatio-temporal scales and the properties of solitons should be studied within the framework of hybrid model.

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)

Direct switching control of DC-DC power electronic converters using hybrid system theory

Energy Technology Data Exchange (ETDEWEB)

Zhao, J.; Lin, F. [Wayne State Univ., Detroit, MI (United States). Dept. of Electrical and Computer Engineering; Wang, C. [Wayne State Univ., Detroit, MI (United States). Dept. of Electrical and Computer Engineering; Wayne State Univ., Detroit, MI (United States). Div. of Engineering Technology

2010-07-01

A direct switching control (DSC) scheme for power electronics converters was described. The system was designed for use in both traditional and renewable energy applications as well as in electric drive vehicles. The proposed control scheme was based on a detailed hybrid system converter model that used model predictive control (MPC), piecewise affine (PWA) approximations and constrained optimal control methods. A DC-DC converter was modelled as a hybrid machine. Switching among different modes of the DC-DC converter were modelled as discrete events controlled by the hybrid controller. The modelling scheme was applied to a Buck converter. The DSC was used to control the switch of the power converter based on a hybrid machine model. Results of the study showed that the method can be used to regulate output voltage and inductor currents. The method also provides fast transient responses and effectively regulates both currents and voltage. The controller can be used to provide immediate responses to dynamic disturbances and output voltage fluctuations. 23 refs., 7 figs.

The use of yellow fluorescent hybrids to indicate mating in Trypanosoma brucei

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Ferris Vanessa

2008-02-01

Full Text Available Abstract Background Trypanosoma brucei undergoes genetic exchange in its insect vector, the tsetse fly, by an unknown mechanism. The difficulties of working with this experimental system of genetic exchange have hampered investigation, particularly because the trypanosome life cycle stages involved cannot be cultured in vitro and therefore must be examined in the insect. Searching for small numbers of hybrid trypanosomes directly in the fly has become possible through the incorporation of fluorescent reporter genes, and we have previously carried out a successful cross using a reporter-repressor strategy. However, we could not be certain that all fluorescent trypanosomes observed in that cross were hybrids, due to mutations of the repressor leading to spontaneous fluorescence, and we have therefore developed an alternative strategy. Results To visualize the production of hybrids in the fly, parental trypanosome clones were transfected with a gene encoding Green Fluorescent Protein (GFP or Red Fluorescent Protein (RFP. Co-infection of flies with red and green fluorescent parental trypanosomes produced yellow fluorescent hybrids, which were easily visualized in the fly salivary glands. Yellow trypanosomes were not seen in midgut or proventricular samples and first appeared in the glands as epimastigotes as early as 13 days after fly infection. Cloned progeny originating from individual salivary glands had yellow, red, green or no fluorescence and were confirmed as hybrids by microsatellite, molecular karyotype and kinetoplast (mitochondrial DNA analyses. Hybrid clones showed biparental inheritance of both nuclear and kinetoplast genomes. While segregation and reassortment of the reporter genes and microsatellite alleles were consistent with Mendelian inheritance, flow cytometry measurement of DNA content revealed both diploid and polyploid trypanosomes among the hybrid progeny clones. Conclusion The strategy of using production of yellow hybrids

The role of meiotic drive in hybrid male sterility.

Science.gov (United States)

McDermott, Shannon R; Noor, Mohamed A F

2010-04-27

Meiotic drive causes the distortion of allelic segregation away from Mendelian expected ratios, often also reducing fecundity and favouring the evolution of drive suppressors. If different species evolve distinct drive-suppressor systems, then hybrid progeny may be sterile as a result of negative interactions of these systems' components. Although the hypothesis that meiotic drive may contribute to hybrid sterility, and thus species formation, fell out of favour early in the 1990s, recent results showing an association between drive and sterility have resurrected this previously controversial idea. Here, we review the different forms of meiotic drive and their possible roles in speciation. We discuss the recent empirical evidence for a link between drive and hybrid male sterility, also suggesting a possible mechanistic explanation for this link in the context of chromatin remodelling. Finally, we revisit the population genetics of drive that allow it to contribute to speciation.

A compact CMA spectrometer with axially integrated hybrid electron-ion gun for ISS, AES and sputter depth profile analysis

International Nuclear Information System (INIS)

Gisler, E.; Bas, E.B.

1986-01-01

Until now, the combined application of electrons and ions in surface analysis required two separate sources for electrons and ions with different incidence angles. The newly developed hybrid electron-ion gun, however, allows bombardment of the same sample area both with noble gas ions and with electrons coming from the same direction. By integrating such a hybrid gun axially in a cylindrical mirror energy analyser (CMA) a sensitive compact single flange spectrometer obtains for ion scattering spectroscopy (ISS), Auger electron spectroscopy (AES), and sputtering all within normal beam incidence. This concept makes accurate beam centering very easy. Additionally, the bombardment from the same direction both for sputtering and for surface analysis brings advantages in depth profiling. The scattering angle for ISS has a constant value of about 138 0 . The hybrid gun delivers typically an electron beam current of -20μA at 3keV for AES, and an ion beam current of +40 nA and +1.2μA at 2 keV for ISS and sputtering respectively. The switching time between ISS, AES, and sputtering mode is about 0.1 s. So this system is best suited for automatically controlled depth profile analysis. The design and operation of this new system will be described and some applications will be discussed. (author)

Chronic irradiation effects on variability of maize and teosinte hybrids

International Nuclear Information System (INIS)

Cerny, J.; Ledecky, J.; Holas, J.

1981-01-01

The plants of the F 1 generation of the back-crosses of maize and teosinte, radiomutant RTZM no. 1 (B1 and B2), were exposed to chronic irradiation with doses from 1000 to 2000 R in a gamma field during their growing season. In the M 4 to F 4 progenies of the B1 hybrid, the correlation between lateness and a higher number of cobs, typical of teosinte, line RTZM no. 1, was significantly distorted. M 4 to F 4 generation lines, characterized by the required higher number of cobs and earliness and by a medium to good combining ability in silage mass yield, were selected from both back-cross hybrids. (author)

Power electronics and electric machinery challenges and opportunities in electric and hybrid vehicles

Energy Technology Data Exchange (ETDEWEB)

Adams, D.J.; Hsu, J.S.; Young, R.W. [Oak Ridge National Lab., TN (United States); Peng, F.Z. [Univ. of Tennessee, Knoxville, TN (United States)

1997-06-01

The development of power electronics and electric machinery presents significant challenges to the advancement of electric and hybrid vehicles. Electronic components and systems development for vehicle applications have progressed from the replacement of mechanical systems to the availability of features that can only be realized through interacting electronic controls and devices. Near-term applications of power electronics in vehicles will enable integrated powertrain controls, integrated chassis system controls, and navigation and communications systems. Future applications of optimized electric machinery will enable highly efficient and lightweight systems. This paper will explore the areas where research and development is required to ensure the continued development of power electronics and electric machines to meet the rigorous demands of automotive applications. Additionally, recent advances in automotive related power electronics and electric machinery at Oak Ridge National Laboratory will be explained. 3 refs., 5 figs.

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.

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)

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)

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

Synergy between electron cyclotron and lower hybrid current drive on Tore Supra

International Nuclear Information System (INIS)

Giruzzi, G.; Artaud, J.F.; Dumont, R.J.; Imbeaux, F.; Bibet, P.; Berger-By, G.; Bouquey, F.; Clary, J.; Darbos, C.; Ekedahl, A.; Hoang, G.T.; Lennholm, M.; Maget, P.; Magne, R.; Segui, J.L.; Bruschi, A.; Granucci, G.

2005-01-01

Improvement (up to a factor ∼ 4) of the electron cyclotron (EC) current drive efficiency in plasmas sustained by lower hybrid (LH) current drive has been demonstrated in stationary conditions on the Tore Supra tokamak. This was made possible by feedback controlled discharges at zero loop voltage, constant plasma current and density. This effect, predicted by kinetic theory, results from a favorable interplay of the velocity space diffusions induced by the two waves: the EC wave pulling low-energy electrons out of the Maxwellian bulk, and the LH wave driving them to high parallel velocities. (author)

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)

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)

Distribution of 45S rDNA in Modern Rose Cultivars (Rosa hybrida), Rosa rugosa, and Their Interspecific Hybrids Revealed by Fluorescence in situ Hybridization.

Science.gov (United States)

Ding, Xiao-Liu; Xu, Ting-Liang; Wang, Jing; Luo, Le; Yu, Chao; Dong, Gui-Min; Pan, Hui-Tang; Zhang, Qi-Xiang

2016-01-01

To elucidate the evolutionary dynamics of the location and number of rDNA loci in the process of polyploidization in the genus Rosa, we examined 45S rDNA sites in the chromosomes of 6 modern rose cultivars (R. hybrida), 5 R. rugosa cultivars, and 20 hybrid progenies by fluorescence in situ hybridization. Variation in the number of rDNA sites in parents and their interspecific hybrids was detected. As expected, 4 rDNA sites were observed in the genomes of 4 modern rose cultivars, while 3 hybridization sites were observed in the 2 others. Two expected rDNA sites were found in 2 R. rugosa cultivars, while in the other 3 R. rugosa cultivars 4 sites were present. Among the 20 R. hybrida × R. rugosa offspring, 13 carried the expected number of rDNA sites, and 1 had 6 hybridization sites, which exceeded the expected number by far. The other 6 offspring had either 2 or 3 hybridization sites, which was less than expected. Differences in the number of rDNA loci were observed in interspecific offspring, indicating that rDNA loci exhibit instability after distant hybridization events. Abnormal chromosome pairing may be the main factor explaining the variation in rDNA sites during polyploidization. © 2016 S. Karger AG, Basel.

Misregulation of Gene Expression and Sterility in Interspecies Hybrids: Causal Links and Alternative Hypotheses.

Science.gov (United States)

Civetta, Alberto

2016-05-01

Understanding the origin of species is of interest to biologist in general and evolutionary biologist in particular. Hybrid male sterility (HMS) has been a focus in studies of speciation because sterility imposes a barrier to free gene flow between organisms, thus effectively isolating them as distinct species. In this review, I focus on the role of differential gene expression in HMS and speciation. Microarray and qPCR assays have established associations between misregulation of gene expression and sterility in hybrids between closely related species. These studies originally proposed disrupted expression of spermatogenesis genes as a causative of sterility. Alternatively, rapid genetic divergence of regulatory elements, particularly as they relate to the male sex (fast-male evolution), can drive the misregulation of sperm developmental genes in the absence of sterility. The use of fertile hybrids (both backcross and F1 progeny) as controls has lent support to this alternative explanation. Differences in gene expression between fertile and sterile hybrids can also be influenced by a pattern of faster evolution of the sex chromosome (fast-X evolution) than autosomes. In particular, it would be desirable to establish whether known X-chromosome sterility factors can act as trans-regulatory drivers of genome-wide patterns of misregulation. Genome-wide expression studies coupled with assays of proxies of sterility in F1 and BC progeny have identified candidate HMS genes but functional assays, and a better phenotypic characterization of sterility phenotypes, are needed to rigorously test how these genes might contribute to HMS.

Derivation of hybrid ES cell lines from two different strains of mice

Directory of Open Access Journals (Sweden)

Ho-Tak Lau

2016-03-01

Full Text Available Parental origin-dependent expression of the imprinted genes is essential for mammalian development. Zfp57 maintains genomic imprinting in mouse embryos and ES cells. To examine the allelic expression patterns of the imprinted genes in ES cells, we obtained multiple hybrid ES clones that were directly derived from the blastocysts generated from the cross between mice on two different genetic backgrounds. The blastocyst-derived ES clones displayed largely intact DNA methylation imprint at the tested imprinted regions. These hybrid ES clones will be useful for future studies to examine the allelic expression of the imprinted genes in ES cells and their differentiated progeny.

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

Protonic/electronic hybrid oxide transistor gated by chitosan and its full-swing low voltage inverter applications

Energy Technology Data Exchange (ETDEWEB)

Chao, Jin Yu [Shanxi Province Key Laboratory High Gravity Chemical Engineering, North University of China, Taiyuan 030051 (China); Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Zhu, Li Qiang, E-mail: lqzhu@nimte.ac.cn; Xiao, Hui [Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Yuan, Zhi Guo, E-mail: ncityzg@163.com [Shanxi Province Key Laboratory High Gravity Chemical Engineering, North University of China, Taiyuan 030051 (China)

2015-12-21

Modulation of charge carrier density in condensed materials based on ionic/electronic interaction has attracted much attention. Here, protonic/electronic hybrid indium-zinc-oxide (IZO) transistors gated by chitosan based electrolyte were obtained. The chitosan-based electrolyte illustrates a high proton conductivity and an extremely strong proton gating behavior. The transistor illustrates good electrical performances at a low operating voltage of ∼1.0 V such as on/off ratio of ∼3 × 10{sup 7}, subthreshold swing of ∼65 mV/dec, threshold voltage of ∼0.3 V, and mobility of ∼7 cm{sup 2}/V s. Good positive gate bias stress stabilities are obtained. Furthermore, a low voltage driven resistor-loaded inverter was built by using an IZO transistor in series with a load resistor, exhibiting a linear relationship between the voltage gain and the supplied voltage. The inverter is also used for decreasing noises of input signals. The protonic/electronic hybrid IZO transistors have potential applications in biochemical sensors and portable electronics.

Bosch automotive electrics and automotive electronics systems and components, networking and hybrid drive

CERN Document Server

2014-01-01

The significance of electrical and electronic systems has increased considerably in the last few years and this trend is set to continue. The characteristics feature of innovative systems is the fact that they can work together in a network. This requires powerful bus systems that the electronic control units can use to exchange information. Networking and the various bus systems used in motor vehicles are the prominent new topic in the 5th edition of the "Automotive Electric, Automotive Electronics" technical manual. The existing chapters have also been updated, so that this new edition brings the reader up to date on the subjects of electrical and electronic systems in the motor vehicle. Content Electrical and electronical systems – Basic principles of networking - Examples of networked vehicles – Bus systems – Architecture of electronic systems – Mechatronics – Elektronics – Electronic control Units – Software – Sensors – Actuators – Hybrid drives – Vehicle electrical system – Start...

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.

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

Apomixis: Engineering the Ability to Harness Hybrid Vigor in Crop Plants.

Science.gov (United States)

Conner, Joann A; Ozias-Akins, Peggy

2017-01-01

Apomixis, commonly defined as asexual reproduction through seed, is a reproductive trait that occurs in only a few minor crops, but would be highly valuable in major crops. Apomixis results in seed-derived progenies that are genetically identical to their maternal parent. The advantage of apomixis would lie in seed propagation of elite food, feed, and biofuel crops that are heterozygous such as hybrid corn and switchgrass or self-pollinating crops for which no commercial-scale hybrid production system is available. While hybrid plants often outperform parental lines in growth and higher yields, production of hybrid seed is accomplished through carefully controlled, labor intensive crosses. Both small farmers in developing countries who produce their own seed and commercial companies that market hybrid seed could benefit from the establishment of engineered apomixis in plants. In this chapter, we review what has been learned from studying natural apomicts and mutations in sexual plants leading to apomixis-like development, plus discuss how the components of apomixis could be successfully engineered in plants.

Third generation hybrid drive. Transmission-based integration of power electronics; Dritte Generation Hybridantrieb. Getriebenahe Integration der Leistungselektronik

Energy Technology Data Exchange (ETDEWEB)

Schoen, Wolfgang [ZF Friedrichshafen AG, Friedrichshafen (DE). Hybridantriebe (F und E); Lutz, Steffen [BMW AG, Muenchen (Germany); Hensler, Alexander [Technische Univ. Chemnitz (Germany); Munding, Andreas [Liebherr Elektronik GmbH, Lindau (Germany); Thoben, Markus [Infineon Technologies AG, Warstein (Germany); Zeidler, Dietmar [Kemet Electronics GmbH, Landsberg am Lech (Germany)

2011-06-15

The power electronics components in today's hybrid vehicles are situated at different places in the vehicle - till now far away from harsh and hot surroundings. In order to develop an integrated solution near the transmission, ZF and BMW launched the research project 'Electric components for active power transmissions' (EfA). On the basis of an eight-speed full hybrid transmission and together with Infineon, Kemet, Liebherr, and the University of Technology of Chemnitz, they are developing a power electronics unit, which facilitates doubling the power density while increasing the operating temperature. The project EfA will be concluded in June 2011. (orig.)

Pseudo-diode based on protonic/electronic hybrid oxide transistor

Science.gov (United States)

Fu, Yang Ming; Liu, Yang Hui; Zhu, Li Qiang; Xiao, Hui; Song, An Ran

2018-01-01

Current rectification behavior has been proved to be essential in modern electronics. Here, a pseudo-diode is proposed based on protonic/electronic hybrid indium-gallium-zinc oxide electric-double-layer (EDL) transistor. The oxide EDL transistors are fabricated by using phosphorous silicate glass (PSG) based proton conducting electrolyte as gate dielectric. A diode operation mode is established on the transistor, originating from field configurable proton fluxes within the PSG electrolyte. Current rectification ratios have been modulated to values ranged between ˜4 and ˜50 000 with gate electrode biased at voltages ranged between -0.7 V and 0.1 V. Interestingly, the proposed pseudo-diode also exhibits field reconfigurable threshold voltages. When the gate is biased at -0.5 V and 0.3 V, threshold voltages are set to ˜-1.3 V and -0.55 V, respectively. The proposed pseudo-diode may find potential applications in brain-inspired platforms and low-power portable systems.

Hybrid Theory of P-Wave Electron-Hydrogen Elastic Scattering

Science.gov (United States)

Bhatia, Anand

2012-01-01

We report on a study of electron-hydrogen scattering, using a combination of a modified method of polarized orbitals and the optical potential formalism. The calculation is restricted to P waves in the elastic region, where the correlation functions are of Hylleraas type. It is found that the phase shifts are not significantly affected by the modification of the target function by a method similar to the method of polarized orbitals and they are close to the phase shifts calculated earlier by Bhatia. This indicates that the correlation function is general enough to include the target distortion (polarization) in the presence of the incident electron. The important fact is that in the present calculation, to obtain similar results only 35-term correlation function is needed in the wave function compared to the 220-term wave function required in the above-mentioned previous calculation. Results for the phase shifts, obtained in the present hybrid formalism, are rigorous lower bounds to the exact phase shifts.

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

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

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.

Comportamento fitotécnico da bananeira 'Prata-Anã' e de seus híbridos Phytotechnical behavior of 'Prata-Anã' banana and progeny hybrids

Directory of Open Access Journals (Sweden)

Sérgio Luiz Rodrigues Donato

2009-12-01

Full Text Available O objetivo deste trabalho foi avaliar o comportamento fitotécnico da bananeira 'Prata-Anã' e de quatro híbridos descendentes, em dois ciclos de produção, no Perímetro Irrigado do Estreito, sudoeste da Bahia. Utilizou-se o delineamento experimental inteiramente casualizado com cinco tratamentos: cultivar Prata-Anã e os híbridos Fhia-01 (BRS Fhia Maravilha, BRS Fhia-18, Fhia-18 e PA42-44, com dez repetições. Foram mensurados os descritores fenotípicos vegetativos, os de ciclo e os de rendimento. Foram observados os seguintes incrementos entre ciclos: na altura da planta, no perímetro do pseudocaule, no número de pencas e de frutos, e na produtividade. O híbrido Fhia-18 apresentou maior porte e perímetro do pseudocaule, a 'Prata-Anã' menor porte (com manutenção desse caráter no PA42-44. Os híbridos foram similares quanto ao número de filhos emitidos. Os híbridos BRS Fhia-18, Fhia-1 e PA42-44 foram mais precoces para a colheita e apresentaram frutos com maior comprimento que a genitora. Fhia-18 apresentou maior quantidade de frutos e PA42-44 menor número de pencas em comparação à genitora. Os híbridos BRS Fhia-18, Fhia-18 e Fhia-1 são mais produtivos que a genitora. 'Prata-Anã' é a mais suscetível à sigatoka-amarela, e PA42-44 é resistente e com maior retenção de folhas na colheita, porém, similar à genitora em produtividade.The objective of this work was to evaluate the phytotechnical behavior of 'Prata-Anã' banana and four progeny hybrids, during two production cycles, in the Perímetro Irrigado do Estreito, southwest of Bahia state, Brazil. The experimental design was completely randomized with five treatments: cultivar 'Prata-Anã' and the hybrids Fhia-01 (BRS Fhia Maravilha, BRS Fhia-18, Fhia 18 and PA42-44, with ten replicates. Phenotypic vegetative descriptors, cycle length and yield were measured. Increases occurred between cycles for: plant height, pseudostem perimeter, number of hands and fruits, and

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

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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

Induced mutants for the improvement of sesame and hybrid seed production

International Nuclear Information System (INIS)

Murty, G.S.S.

2001-01-01

With an overall objective to develop hybrids in sesame, induced mutants were used in cross breeding and five initial yield trials were conducted. For obtaining the mutant hybrids, recessive morphological mutants were used as female, and check varieties as male parents. In each trial, seed yields of mutant hybrids were compared with: i) the original parent in which the mutants were induced, ii) best check variety and iii) best cultivar hybrid. Among 138 mutant hybrids evaluated between 1994 and 1997, 18 showed superiority. In the development of hybrids, it is also desirable to have male sterile lines. By irradiating seeds with 400 Gy gamma rays, four genetic male sterile mutants were isolated. One of them, TMST-11 appears to be promising for breeding programme showing 100% male sterility and characterised by dark green foliage. To study the percent outcrossing, a monogenic chlorina mutant which can be identified from the seedling stage, was used in experiments conducted for two years. Among open pollinated plants, 92-98% plants were found outcrossed. Based on plant to row progenies, percent outcrossing ranged between 0.0 to 13.8%. (author)

Research Update: The electronic structure of hybrid perovskite layers and their energetic alignment in devices

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Selina Olthof

2016-09-01

Full Text Available In recent years, the interest in hybrid organic–inorganic perovskites has increased at a rapid pace due to their tremendous success in the field of thin film solar cells. This area closely ties together fundamental solid state research and device application, as it is necessary to understand the basic material properties to optimize the performances and open up new areas of application. In this regard, the energy levels and their respective alignment with adjacent charge transport layers play a crucial role. Currently, we are lacking a detailed understanding about the electronic structure and are struggling to understand what influences the alignment, how it varies, or how it can be intentionally modified. This research update aims at giving an overview over recent results regarding measurements of the electronic structure of hybrid perovskites using photoelectron spectroscopy to summarize the present status.

Hybrid functional pseudopotentials

Science.gov (United States)

Yang, Jing; Tan, Liang Z.; Rappe, Andrew M.

2018-02-01

The consistency between the exchange-correlation functional used in pseudopotential construction and in the actual density functional theory calculation is essential for the accurate prediction of fundamental properties of materials. However, routine hybrid density functional calculations at present still rely on generalized gradient approximation pseudopotentials due to the lack of hybrid functional pseudopotentials. Here, we present a scheme for generating hybrid functional pseudopotentials, and we analyze the importance of pseudopotential density functional consistency for hybrid functionals. For the PBE0 hybrid functional, we benchmark our pseudopotentials for structural parameters and fundamental electronic gaps of the Gaussian-2 (G2) molecular dataset and some simple solids. Our results show that using our PBE0 pseudopotentials in PBE0 calculations improves agreement with respect to all-electron calculations.

Evaluation of a hybrid paper-electronic medication management system at a residential aged care facility.

Science.gov (United States)

Elliott, Rohan A; Lee, Cik Yin; Hussainy, Safeera Y

2016-06-01

Objectives The aims of the study were to investigate discrepancies between general practitioners' paper medication orders and pharmacy-prepared electronic medication administration charts, back-up paper charts and dose-administration aids, as well as delays between prescribing, charting and administration, at a 90-bed residential aged care facility that used a hybrid paper-electronic medication management system. Methods A cross-sectional audit of medication orders, medication charts and dose-administration aids was performed to identify discrepancies. In addition, a retrospective audit was performed of delays between prescribing and availability of an updated electronic medication administration chart. Medication administration records were reviewed retrospectively to determine whether discrepancies and delays led to medication administration errors. Results Medication records for 88 residents (mean age 86 years) were audited. Residents were prescribed a median of eight regular medicines (interquartile range 5-12). One hundred and twenty-five discrepancies were identified. Forty-seven discrepancies, affecting 21 (24%) residents, led to a medication administration error. The most common discrepancies were medicine omission (44.0%) and extra medicine (19.2%). Delays from when medicines were prescribed to when they appeared on the electronic medication administration chart ranged from 18min to 98h. On nine occasions (for 10% of residents) the delay contributed to missed doses, usually antibiotics. Conclusion Medication discrepancies and delays were common. Improved systems for managing medication orders and charts are needed. What is known about the topic? Hybrid paper-electronic medication management systems, in which prescribers' orders are transcribed into an electronic system by pharmacy technicians and pharmacists to create medication administration charts, are increasingly replacing paper-based medication management systems in Australian residential aged care

Using GPU to calculate electron dose for hybrid pencil beam model

International Nuclear Information System (INIS)

Guo Chengjun; Li Xia; Hou Qing; Wu Zhangwen

2011-01-01

Hybrid pencil beam model (HPBM) offers an efficient approach to calculate the three-dimension dose distribution from a clinical electron beam. Still, clinical radiation treatment activity desires faster treatment plan process. Our work presented the fast implementation of HPBM-based electron dose calculation using graphics processing unit (GPU). The HPBM algorithm was implemented in compute unified device architecture running on the GPU, and C running on the CPU, respectively. Several tests with various sizes of the field, beamlet and voxel were used to evaluate our implementation. On an NVIDIA GeForce GTX470 GPU card, we achieved speedup factors of 2.18- 98.23 with acceptable accuracy, compared with the results from a Pentium E5500 2.80 GHz Dual-core CPU. (authors)

Electron currents in field reversed mirror dynamics: Theory and hybrid simulation

International Nuclear Information System (INIS)

Stark, R.A.

1987-01-01

To model the dynamics of the Field-Reversed Mirror (FRM) as a whole we have developed a 1-D radical hybrid code which also incorporates the above electron null current model. This code, named FROST, models the plasma as azimuthally symmetric with no axial dependence. A multi-group method in energy and canonical angular momentum describes the large-orbit ions from the beam. Massless fluid equations describe electrons and low energy ions. Since a fluid treatment for electrons is invalid near a field null, the null region electron current model discussed above has been included for this region, a unique feature. Results of simulation of neutral beam start-up in a 2XIIB-like plasma is discussed. There FROST predicts that electron currents will retard, but not prevent reversal of the magnetic field at the plasma center. These results are optimistic when compared to actual reversal experiments in 2XIIB, because there finite axial length effects and micro-instabilities substantially deteriorated the ion confinement. Nevertheless, because of the importance of the electron current in a low field region in the FRM, FROST represents a valuable intermediate step toward a more complete description of FRM dynamics. 54 refs., 50 figs., 3 tabs

Evidence to support natural hybridization between Anopheles sinensis and Anopheles kleini (Diptera: Culicidae): possibly a significant mechanism for gene introgression in sympatric populations

Science.gov (United States)

2014-01-01

Background Malaria caused by Plasmodium vivax is still a public health problem in the Republic of Korea (ROK), particularly regarding the recent re-emergence of this malarial species near the demilitarized zone in northwestern Paju City, Gyeonggi-do Province. Currently, at least 4 species (An. kleini, An. pullus, An. belenrae and An. lesteri) of the Hyrcanus Group are reported as possible natural vectors of vivax malaria in the ROK, and An. sinensis, which is the most dominant species, has long been incriminated as an important natural vector of this P. vivax. However, An. sinensis was ranked recently as a low potential vector. According to the discovery of natural hybrids between An. sinensis (a low potential vector for P. vivax) and An. kleini (a high potential vector for P. vivax) in Paju City, intensive investigation of this phenomenon is warranted under laboratory conditions. Methods Mosquitoes were collected during 2010-2012 from Paju City, ROK. Hybridization experiments used iso-female line colonies of these anophelines together with DNA analysis of ribosomal DNA [second internal transcribed spacer (ITS2)] and mitochondrial DNA [cytochrome c oxidase subunit I (COI)] of the parental colonies, F1-hybrids and repeated backcross progenies were performed intensively by using a PCR-based assay and pyrosequencing technology. Results The results from hybridization experiments and molecular investigations revealed that the mitochondrial COI gene was introgressed from An. sinensis into An. kleini. The An. sinensis progenies obtained from consecutive repeated backcrosses in both directions, i.e., F2-11 progeny [(An. sinensis x An. kleini) x An. sinensis] and F3-5 progeny [(An. kleini x An. sinensis) x An. kleini] provided good supportive evidence. Conclusions This study revealed introgression of the mitochondrial COI gene between An. sinensis and An. kleini through consecutive repeated backcrosses under laboratory conditions. This new body of knowledge will be

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

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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.

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.

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

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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. 

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)

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

Removal of the lower hybrid (LH) frequency time scale in test electron simulations of LH-induced tokamak edge electron flow

Czech Academy of Sciences Publication Activity Database

Fuchs, Vladimír; Petržílka, Václav; Gunn, J. P.; Goniche, M.

2002-01-01

Roč. 52, supplement D (2002), s. 45-50 ISSN 0011-4626. [Symposium on Plasma Physics and Technology/20th./. Prague, 10.06.2002-13.06.2002] Institutional research plan: CEZ:AV0Z2043910 Keywords : tokamak, edge electrons, lower hybrid antenna Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.311, year: 2002

Mediated Electron Transfer at Vertically Aligned Single-Walled Carbon Nanotube Electrodes During Detection of DNA Hybridization

Science.gov (United States)

Wallen, Rachel; Gokarn, Nirmal; Bercea, Priscila; Grzincic, Elissa; Bandyopadhyay, Krisanu

2015-06-01

Vertically aligned single-walled carbon nanotube (VASWCNT) assemblies are generated on cysteamine and 2-mercaptoethanol (2-ME)-functionalized gold surfaces through amide bond formation between carboxylic groups generated at the end of acid-shortened single-walled carbon nanotubes (SWCNTs) and amine groups present on the gold surfaces. Atomic force microscopy (AFM) imaging confirms the vertical alignment mode of SWCNT attachment through significant changes in surface roughness compared to bare gold surfaces and the lack of any horizontally aligned SWCNTs present. These SWCNT assemblies are further modified with an amine-terminated single-stranded probe-DNA. Subsequent hybridization of the surface-bound probe-DNA in the presence of complementary strands in solution is followed using impedance measurements in the presence of Fe(CN)6 3-/4- as the redox probe in solution, which show changes in the interfacial electrochemical properties, specifically the charge-transfer resistance, due to hybridization. In addition, hybridization of the probe-DNA is also compared when it is attached directly to the gold surfaces without any intermediary SWCNTs. Contrary to our expectations, impedance measurements show a decrease in charge-transfer resistance with time due to hybridization with 300 nM complementary DNA in solution with the probe-DNA attached to SWCNTs. In contrast, an increase in charge-transfer resistance is observed with time during hybridization when the probe-DNA is attached directly to the gold surfaces. The decrease in charge-transfer resistance during hybridization in the presence of VASWCNTs indicates an enhancement in the electron transfer process of the redox probe at the VASWCNT-modified electrode. The results suggest that VASWCNTs are acting as mediators of electron transfer, which facilitate the charge transfer of the redox probe at the electrode-solution interface.

Generation of auroral kilometric radiation in upper hybrid wave-lower hybrid soliton interaction

International Nuclear Information System (INIS)

Pottelette, R.; Dubouloz, N.; Treumann, R.A.

1992-01-01

Sporadic bursts of auroral kilometric radiation (AKR) associated with strong bursty electrostatic turbulence in the vicinity of the lower hybrid frequency have been frequently recorded in the AKR source region by the Viking satellite. The variation time scale of these emissions is typically 1 s, long enough for lower hybrid waves to grow to amplitudes of several hundred millivolts per meter and to evolve nonlinearly into solitons. On the basis on these observations it is suggested that formation of lower hybrid solitons may play a role in the generation of AKR. A theoretical model is proposed which is based on the direct acceleration of electrons in the combined lower hybrid soliton and upper hybrid wave fields. The solitons act as sporadic, localized antennas allowing for efficient conversions of the electrostatic energy stored in upper hybrid waves into electromagnetic radiation at a frequency above the X mode cutoff. Excitation of lower hybrid waves is due to the presence of energetic electron beams in the auroral zone found to be associated with steep plasma density gradients. Upper hybrid waves can be excited by a population of energetic electrons with loss cone distributions. The power of the electromagnetic radiation obtained is only noticeable in regions where the plasma frequency is less than the electron gyrofrequency. The theory predicts spectral power densities of the order of 10 -11 to 10 -9 W m -2 Hz -1 in the source region, in good agreement with the Viking observations. The sporadic nature of the radiation derives from lower hybrid soliton collapses which occur on ∼1-s time scales

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

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.

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.

Interspecific hybridization, polyploidization, and backcross of Brassica oleracea var. alboglabra with B. rapa var. purpurea morphologically recapitulate the evolution of Brassica vegetables.

Science.gov (United States)

Zhang, Xiaohui; Liu, Tongjin; Li, Xixiang; Duan, Mengmeng; Wang, Jinglei; Qiu, Yang; Wang, Haiping; Song, Jiangping; Shen, Di

2016-01-04

Brassica oleracea and B. rapa are two important vegetable crops. Both are composed of dozens of subspecies encompassing hundreds of varieties and cultivars. Synthetic B. napus with these two plants has been used extensively as a research model for the investigation of allopolyploid evolution. However, the mechanism underlying the explosive evolution of hundreds of varieties of B. oleracea and B. rapa within a short period is poorly understood. In the present study, interspecific hybridization between B. oleracea var. alboglabra and B. rapa var. purpurea was performed. The backcross progeny displayed extensive morphological variation, including some individuals that phenocopied subspecies other than their progenitors. Numerous interesting novel phenotypes and mutants were identified among the backcross progeny. The chromosomal recombination between the A and C genomes and the chromosomal asymmetric segregation were revealed using Simple Sequence Repeats (SSR) markers. These findings provide direct evidence in support of the hypothesis that interspecific hybridization and backcrossing have played roles in the evolution of the vast variety of vegetables among these species and suggest that combination of interspecific hybridization and backcrossing may facilitate the development of new mutants and novel phenotypes for both basic research and the breeding of new vegetable crops.

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.

Transmission electron microscopic method for gene mapping on polytene chromosomes by in situ hybridization

OpenAIRE

Wu, Madeline; Davidson, Norman

1981-01-01

A transmission electron microscope method for gene mapping by in situ hybridization to Drosophila polytene chromosomes has been developed. As electron-opaque labels, we use colloidal gold spheres having a diameter of 25 nm. The spheres are coated with a layer of protein to which Escherichia coli single-stranded DNA is photochemically crosslinked. Poly(dT) tails are added to the 3' OH ends of these DNA strands, and poly(dA) tails are added to the 3' OH ends of a fragmented cloned Drosophila DN...

Acceleration of electrons in the vicinity of a lower hybrid waveguide array

International Nuclear Information System (INIS)

Fuchs, V.; Goniche, M.; Demers, Y.; Jacquet, P.; Mailloux, J.

1996-01-01

The interaction of tokamak plasma edge electrons with the electric near field generated by a lower hybrid slow wave antenna is studied. Antenna field spectra of interest for current drive and/or plasma heating have lobes at high-n parallel values (n parallel approx-gt 30) intense enough for resonant acceleration of the relatively cold (∼25 eV) edge electrons. For waveguide electric fields, typically around 3 kV/cm, the higher-order modes overlap in the phase-space [B. V. Chirikov, Phys. Rep. 52, 263 (1979)], so that electron global stochasticity is induced. For Tokamak de Varennes (TdeV) [Dacute ecoste et al., Phys. Plasmas 1, 1497 (1994)] conditions and for 90 degree waveguide phasing, the stochastic limit in the current drive direction is about 2 keV, determined by the last overlapping mode. The progress of electrons through accessible phase space is very efficient: the TdeV 32 waveguide array can accelerate the electrons to the possible limit. An area-preserving map is derived to study the electron dynamics. Surface-of-section plots fully confirm the resonant wave-particle nature of the interaction. copyright 1996 American Institute of Physics

Selection processes in a citrus hybrid population using RAPD markers

Directory of Open Access Journals (Sweden)

Oliveira Roberto Pedroso de

2003-01-01

Full Text Available The objective of this work was to evaluate the processes of selection in a citrus hybrid population using segregation analysis of RAPD markers. The segregation of 123 RAPD markers between 'Cravo' mandarin (Citrus reticulata Blanco and 'Pêra' sweet orange (C. sinensis (L. Osbeck was analysed in a F1 progeny of 94 hybrids. Genetic composition, diversity, heterozygosity, differences in chromosomal structure and the presence of deleterious recessive genes are discussed based on the segregation ratios obtained. A high percentage of markers had a skeweness of the 1:1 expected segregation ratio in the F1 population. Many markers showed a 3:1 segregation ratio in both varieties and 1:3 in 'Pêra' sweet orange, probably due to directional selection processes. The distribution analysis of the frequencies of the segregant markers in a hybrid population is a simple method which allows a better understanding of the genetics of citrus group.

The formation of diploid and triploid hybrids of female grass carp × male blunt snout bream and their 5S rDNA analysis.

Science.gov (United States)

He, Weiguo; Xie, Lihua; Li, Tangluo; Liu, Shaojun; Xiao, Jun; Hu, Jie; Wang, Jing; Qin, Qinbo; Liu, Yun

2013-11-23

Hybridization is a useful strategy to alter the genotypes and phenotypes of the offspring. It could transfer the genome of one species to another through combing the different genome of parents in the hybrid offspring. And the offspring may exhibit advantages in growth rate, disease resistance, survival rate and appearance, which resulting from the combination of the beneficial traits from both parents. Diploid and triploid hybrids of female grass carp (Ctenopharyngodon idellus, GC, Cyprininae, 2n = 48) × male blunt snout bream (Megalobrama amblycephala, BSB, Cultrinae, 2n = 48) were successfully obtained by distant hybridization. Diploid hybrids had 48 chromosomes, with one set from GC and one set from BSB. Triploid hybrids possessed 72 chromosomes, with two sets from GC and one set from BSB.The morphological traits, growth rates, and feeding ecology of the parents and hybrid offspring were compared and analyzed. The two kinds of hybrid offspring exhibited significantly phenotypic divergence from GC and BSB. 2nGB hybrids showed similar growth rate compared to that of GC, and 3nGB hybrids significantly higher results. Furthermore, the feeding ecology of hybrid progeny was omnivorous.The 5S rDNA of GC, BSB and their hybrid offspring were also cloned and sequenced. There was only one type of 5S rDNA (designated type I: 180 bp) in GC and one type of 5S rDNA (designated type II: 188 bp) in BSB. However, in the hybrid progeny, diploid and triploid hybrids both inherited type I and type II from their parents, respectively. In addition, a chimera of type I and type II was observed in the genome of diploid and triploid hybrids, excepting a 10 bp of polyA insertion in type II sequence of the chimera of the diploid hybrids. This is the first report of diploid and triploid hybrids being produced by crossing GC and BSB, which have the same chromosome number. The obtainment of two new hybrid offspring has significance in fish genetic breeding. The results illustrate the effect

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)

Highly active bidirectional electron transfer by a self-assembled electroactive reduced-graphene-oxide-hybridized biofilm.

Science.gov (United States)

Yong, Yang-Chun; Yu, Yang-Yang; Zhang, Xinhai; Song, Hao

2014-04-22

Low extracellular electron transfer performance is often a bottleneck in developing high-performance bioelectrochemical systems. Herein, we show that the self-assembly of graphene oxide and Shewanella oneidensis MR-1 formed an electroactive, reduced-graphene-oxide-hybridized, three-dimensional macroporous biofilm, which enabled highly efficient bidirectional electron transfers between Shewanella and electrodes owing to high biomass incorporation and enhanced direct contact-based extracellular electron transfer. This 3D electroactive biofilm delivered a 25-fold increase in the outward current (oxidation current, electron flux from bacteria to electrodes) and 74-fold increase in the inward current (reduction current, electron flux from electrodes to bacteria) over that of the naturally occurring biofilms. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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)

An open-source framework for analyzing N-electron dynamics. II. Hybrid density functional theory/configuration interaction methodology.

Science.gov (United States)

Hermann, Gunter; Pohl, Vincent; Tremblay, Jean Christophe

2017-10-30

In this contribution, we extend our framework for analyzing and visualizing correlated many-electron dynamics to non-variational, highly scalable electronic structure method. Specifically, an explicitly time-dependent electronic wave packet is written as a linear combination of N-electron wave functions at the configuration interaction singles (CIS) level, which are obtained from a reference time-dependent density functional theory (TDDFT) calculation. The procedure is implemented in the open-source Python program detCI@ORBKIT, which extends the capabilities of our recently published post-processing toolbox (Hermann et al., J. Comput. Chem. 2016, 37, 1511). From the output of standard quantum chemistry packages using atom-centered Gaussian-type basis functions, the framework exploits the multideterminental structure of the hybrid TDDFT/CIS wave packet to compute fundamental one-electron quantities such as difference electronic densities, transient electronic flux densities, and transition dipole moments. The hybrid scheme is benchmarked against wave function data for the laser-driven state selective excitation in LiH. It is shown that all features of the electron dynamics are in good quantitative agreement with the higher-level method provided a judicious choice of functional is made. Broadband excitation of a medium-sized organic chromophore further demonstrates the scalability of the method. In addition, the time-dependent flux densities unravel the mechanistic details of the simulated charge migration process at a glance. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Highly efficient hybrid photovoltaics based on hyperbranched three-dimensional TiO2 electron transporting materials

KAUST Repository

Mahmood, Khalid; Swain, Bhabani Sankar; Amassian, Aram

2015-01-01

A 3D hyperbranched TiO2 electron transporting material is demonstrated, which exhibits superior carrier transport and lifetime, as well as excellent infiltration, leading to highly efficient mesostructured hybrid solar cells, such as lead-halide perovskites (15.5%) and dye-sensitized solar cells (11.2%).

Highly efficient hybrid photovoltaics based on hyperbranched three-dimensional TiO2 electron transporting materials

KAUST Repository

Mahmood, Khalid

2015-03-23

A 3D hyperbranched TiO2 electron transporting material is demonstrated, which exhibits superior carrier transport and lifetime, as well as excellent infiltration, leading to highly efficient mesostructured hybrid solar cells, such as lead-halide perovskites (15.5%) and dye-sensitized solar cells (11.2%).

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

Oxide nanomembrane hybrids with enhanced mechano- and thermo-sensitivity for semitransparent epidermal electronics.

Science.gov (United States)

Park, Minjoon; Do, Kyungsik; Kim, Jaemin; Son, Donghee; Koo, Ja Hoon; Park, Jinkyung; Song, Jun-Kyul; Kim, Ji Hoon; Lee, Minbaek; Hyeon, Taeghwan; Kim, Dae-Hyeong

2015-05-01

Oxide nanomembrane hybrids with enhanced mechano- and thermo-sensitivity for semitransparent epidermal electronics are developed. The use of nanomaterials (single wall nanotubes and silver nanoparticles) embedded in the oxide nanomembranes significantly enhances mechanical and thermal sensitivities. These mechanical and thermal sensors are utilized in wheelchair control and hypothermia detection, which are useful for patients with strokes. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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.

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)

Optimized calculation of the synergy conditions between electron cyclotron current drive and lower hybrid current drive on EAST

International Nuclear Information System (INIS)

Wei Wei; Ding Bo-Jiang; Li Miao-Hui; Zhang Xin-Jun; Wang Xiao-Jie; Peysson, Y; Decker, J; Zhang Lei

2016-01-01

The optimized synergy conditions between electron cyclotron current drive (ECCD) and lower hybrid current drive (LHCD) with normal parameters of the EAST tokamak are studied by using the C3PO/LUKE code based on the understanding of the synergy mechanisms so as to obtain a higher synergistic current and provide theoretical reference for the synergistic effect in the EAST experiment. The dependences of the synergistic effect on the parameters of two waves (lower hybrid wave (LHW) and electron cyclotron wave (ECW)), including the radial position of the power deposition, the power value of the LH and EC waves, and the parallel refractive indices of the LHW (N ∥ ) are presented and discussed. (paper)

A hybrid instrument combining electronic and photonic tunnelling for surface analysis

International Nuclear Information System (INIS)

Pechou, R.; Ajustron, F.; Seine, G.; Coratger, R.; Maurel, C.; Beauvillain, J.

2004-01-01

A PSTM working in the collection mode and based on an STM probe-sample regulation scheme has been developed. This original hybrid instrument for surface analysis uses apertureless metal-coated chemically etched optical fibres. The use of an electronic tunnelling-based feedback loop significantly reduces tip-sample distance and leads to the collection of a high level near-field optical (NFO) signal. A simple amplified photodiode is thus used to perform optical signal acquisition and to draw electromagnetic field maps of sample surfaces. Experimental results on nanostructured gold surfaces are presented

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

Structural, electronic, and optical properties of GaInO{sub 3}: A hybrid density functional study

Energy Technology Data Exchange (ETDEWEB)

Wang, V., E-mail: wangvei@icloud.com; Ma, D.-M.; Liu, R.-J.; Yang, C.-M. [Department of Applied Physics, Xi' an University of Technology, Xi' an 710054 (China); Xiao, W. [State Key Lab of Nonferrous Metals and Processes, General Research Institute for Nonferrous Metals, Beijing 100088 (China)

2014-01-28

The structural, electronic, and optical properties of GaInO{sub 3} have been studied by first-principles calculations based on Heyd-Scuseria-Ernzerhof hybrid functional theory. The optical properties, including the optical reflectivity, refractive index, extinction coefficient, absorption coefficient, and electron energy loss are discussed for radiation up to 60 eV together with the calculated electronic structure. Our results predicted that GaInO{sub 3} displays good transparency over the whole vision region, which is in good agreement with the experimental data available in the literature.

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.

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

UV irradiation as a tool for obtaining asymmetric somatic hybrids between Nicotiana plumbaginifolia and Lycopersicon esculentum

International Nuclear Information System (INIS)

Vlahova, M.; Hinnisdaels, S.; Frulleux, F.; Claeys, M.; Atanassov, A.; Jacobs, M.

1997-01-01

UV-irradiated kanamycin-resistant Lycopersicon esculentum leaf protoplasts were fused with wild-type Nicotiana plumbaginifolia leaf protoplasts. Hybrid calli were recovered after selection in kanamycin-containing medium and subsequently regenerated. Cytological analysis of these regenerants showed that several (2–4) tomato chromosomes, or chromosome fragments, were present in addition to a polyploid Nicotiana genome complement. All lines tested had neomycin phosphotransferase (NPTII) activity and the presence of the kanamycin gene was shown by Southern blotting. In two cases a different hybridization profile for the kanamycin gene, compared to the tomato donor partner, was observed, suggesting the occurence of intergenomic recombination events. The hybrid nature of the regenerants was further confirmed by Southernblotting experiments using either a ribosomal DNA sequence or a tomato-specific repeat as probes. The hybrids were partially fertile and some progeny could be obtained. Our results demonstrate that UV irradiation is a valuable alternative for asymmetric cell-hybridization experiments. (author)

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.

Changes in oil composition after chronic irradiation of winter and spring zero-erucic rape hybrids

International Nuclear Information System (INIS)

Fabry, A.; Cerny, J.

1980-01-01

Hybrid plants of the F1 generation of erucic-free spring Canadian rape and some winter rape cultivars containing erucic acid were irradiated in a gamma field with doses ranging between 5973 and 329 R during vegetation. Chronic irradiation increased significantly the frequency of zero- or low-erucic genotypes in the segregating F2 generation. Chronic irradiation disturbed the correlations between the contents of the studied fatty acids in the hybrid F1, F2 and F3 progenies. Lines of zero- and low-erucic winter rapes with a reduced content of linolenic acid and increased content of linoleic acid were obtained by selection. (author)

Medium-energy electrons and heavy ions in Jupiter's magnetosphere - Effects of lower hybrid wave-particle interactions

Science.gov (United States)

Barbosa, D. D.

1986-01-01

A theory of medium-energy (about keV) electrons and heavy ions in Jupiter's magnetosphere is presented. Lower hybrid waves are generated by the combined effects of a ring instability of neutral wind pickup ions and the modified two-stream instability associated with transport of cool Iogenic plasma. The quasi-linear energy diffusion coefficient for lower hybrid wave-particle interactions is evaluated, and several solutions to the diffusion equation are given. Calculations based on measured wave properties show that the noise substantially modifies the particle distribution functions. The effects are to accelerate superthermal ions and electrons to keV energies and to thermalize the pickup ions on time scales comparable to the particle residence time. The S(2+)/S(+) ratio at medium energies is a measure of the relative contribution from Iogenic thermal plasma and neutral wind ions, and this important quantity should be determined from future measurements. The theory also predicts a preferential acceleration of heavy ions with an accleration time that scales inversely with the root of the ion mass. Electrons accelerated by the process contribute to further reionization of the neutral wind by electron impact, thus providing a possible confirmation of Alfven's critical velocity effect in the Jovian magnetosphere.

Hybrid electric vehicle thermal management and study of the power electronics cooling; Gestion thermique du vehicule hybride et etude du refroidissement de l'electronique de puissance

Energy Technology Data Exchange (ETDEWEB)

Rouaud, C.

2004-07-01

For decreasing the engine's consumption and pollutant emissions, automobile makers are developing hybrid electric vehicles incorporating an electric motor and power electronics leading to new under-hood thermal constraints. This is why we first present the tests results of a new common cooling circuit for all the vehicle components. With the aim of developing new energy management strategies between the components, we have chosen the nodal method to simulate the thermal behaviour of the engine, the electric motor, the power electronics and the cooling circuit. The second part of this thesis deals with a thermal-hydraulic analysis of several power electronics cooling methods, which has led us to choose the multiple jet impingement cooling. Several tests have been made for characterising the performances of this technique and enabled us to establish an optimal configuration. The last part shows the thermal simulation results run with the help of an innovative reduction method of thermal models applied to the power electronics. This technique allowed us to have a low cost of time simulation and will permit, in the future, the real-time control of the hybrid electric vehicle components. (author)

Enabling fast electron transfer through both bacterial outer-membrane redox centers and endogenous electron mediators by polyaniline hybridized large-mesoporous carbon anode for high-performance microbial fuel cells

International Nuclear Information System (INIS)

Zou, Long; Qiao, Yan; Zhong, Canyu; Li, Chang Ming

2017-01-01

Both physical structure and chemical property of an electrode play critical roles in extracellular electron transfer from microbes to electrodes in microbial fuel cells (MFCs). Herein a novel polyaniline hybridized large mesoporous carbon (PANI-LMC) anode is fabricated from natural biomass by nanostructured CaCO 3 template-assisted carbonization followed by in situ chemical polymerizing PANI to enable fast extracellular electron transfer, in which the LMC with rich disorder-interconnected large mesopores (∼20−50 nm) and large surface area facilitates a fast mediated electron transfer through electron mediators, while the decorated PANI on LMC surface enables the direct electron transfer via bacterial outer-membrane redox centers. Owing to the unique synergistic effect from both excellent electron transfer paths, the PANI-LMC hybrid anode harvests high power electricity with a maximum output power density of 1280 mW m −2 in Shewanella putrefaciens CN32 MFCs, 10-fold higher than that of conventional carbon cloth. The findings from this work suggest a new insight on design of high-efficient anode according to the multiple and flexible electrochemical process for practical MFC applications.

A segmented Hybrid Photon Detector with integrated auto-triggering front-end electronics for a PET scanner

CERN Document Server

Chesi, Enrico Guido; Joram, C; Mathot, S; Séguinot, Jacques; Weilhammer, P; Ciocia, F; De Leo, R; Nappi, E; Vilardi, I; Argentieri, A; Corsi, F; Dragone, A; Pasqua, D

2006-01-01

We describe the design, fabrication and test results of a segmented Hybrid Photon Detector with integrated auto-triggering front-end electronics. Both the photodetector and its VLSI readout electronics are custom designed and have been tailored to the requirements of a recently proposed novel geometrical concept of a Positron Emission Tomograph. Emphasis is put on the PET specific features of the device. The detector has been fabricated in the photocathode facility at CERN.

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.

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.

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.

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.

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.

Research of a hybrid undulator

International Nuclear Information System (INIS)

Ma Youwu; Wu Bing; Liu Bo

1995-12-01

A 1.5 m tapered hybrid undulator has been designed and built for mid-infrared free electron laser experiments at CIAE. The undulator utilizes the REC-steel hybrid configuration. The magnetic gap and magnetic field taper can be continuously adjusted. The rms error of the peak field is less than 0.53%. The electron trajectory deviation is around 0.03 mm. The design of undulator, sorting of magnets in hybrid undulator using simulated annealing technique, the motion of electron beam in the ideal and measured magnetic field, magnetic field measurement technique and magnetic field adjustment are described. (6 refs., 10 figs., 1 tab)

Asymmetry and polymorphism of hybrid male sterility during the early stages of speciation in house mice.

Science.gov (United States)

Good, Jeffrey M; Handel, Mary Ann; Nachman, Michael W

2008-01-01

House mice offer a powerful system for dissecting the genetic basis of phenotypes that isolate species in the early stages of speciation. We used a series of reciprocal crosses between wild-derived strains of Mus musculus and M. domesticus to examine F(1) hybrid male sterility, one of the primary phenotypes thought to isolate these species. We report four main results. First, we found significantly smaller testes and fewer sperm in hybrid male progeny of most crosses. Second, in some crosses hybrid male sterility was asymmetric and depended on the species origin of the X chromosome. These observations confirm and extend previous findings, underscoring the central role that the M. musculus X chromosome plays in reproductive isolation. Third, comparisons among reciprocal crosses revealed polymorphism at one or more hybrid incompatibilities within M. musculus. Fourth, the spermatogenic phenotype of this polymorphic interaction appears distinct from previously described hybrid incompatibilities between these species. These data build on previous studies of speciation in house mice and show that the genetic basis of hybrid male sterility is fairly complex, even at this early stage of divergence.

N-type polymers as electron extraction layers in hybrid perovskite solar cells with improved ambient stability

NARCIS (Netherlands)

Shao, S.; Chen, Z.; Fang, H. -H.; ten Brink, G. H.; Bartesaghi, D.; Adjokatse, S.; Koster, L. J. A.; Kooi, B. J.; Facchetti, A.; Loi, M. A.

2016-01-01

We studied three n-type polymers of the naphthalenediimide-bithiophene family as electron extraction layers (EELs) in hybrid perovskite solar cells. The recombination mechanism in these devices is found to be heavily influenced by the EEL transport properties. The maximum efficiency of the devices

Electronic properties of B and Al doped graphane: A hybrid density functional study

Science.gov (United States)

Mapasha, R. E.; Igumbor, E.; Andriambelaza, N. F.; Chetty, N.

2018-04-01

Using a hybrid density functional theory approach parametrized by Heyd, Scuseria and Ernzerhof (HSE06 hybrid functional), we study the energetics, structural and electronic properties of a graphane monolayer substitutionally doped with the B (BCH) and Al (AlCH) atoms. The BCH defect can be integrated within a graphane monolayer at a relative low formation energy, without major structural distortions and symmetry breaking. The AlCH defect relaxes outward of the monolayer and breaks the symmetry. The density of states plots indicate that BCH doped graphane monolayer is a wide band gap semiconductor, whereas the AlCH defect introduces the spin dependent mid gap states at the vicinity of the Fermi level, revealing a metallic character with the pronounced magnetic features. We further examine the response of the Al dependent spin states on the multiple charge states doping. We find that the defect formation energy, structural and electronic properties can be altered via charge state modulation. The +1 charge doping opens an energy band gap of 1.75 eV. This value corresponds to the wavelength in the visible spectrum, suggesting an ideal material for solar cell absorbers. Our study fine tunes the graphane band gap through the foreign atom doping as well as via defect charge state modulation.

Mechanisms of the negative synergy effect between electron cyclotron current drive and lower hybrid current drive in tokamak

International Nuclear Information System (INIS)

Chen Shaoyong; Hong Binbin; Tang Changjian; Yang Wen; Zhang Xinjun

2013-01-01

The synergy current drive by combining electron cyclotron wave (ECW) with lower hybrid wave (LHW) can be used to either increase the noninductive current drive efficiency or shape the plasma current profile. In this paper, the synergy current drive by ECW and LHW is studied with numerical simulation. The nonlinear relationship between the wave powers and the synergy current of ECW and LHW is revealed. When the LHW power is small, the synergy current reduces as the ECW power increases, and the synergy current is even reduced to lower than zero, which is referred as negative synergy in the this context. Research shows that the mechanism of the negative synergy is the peaking effect of LHW power profile and the trapped electrons effect. The present research is helpful for understanding the physics of synergy between electron cyclotron current drive and lower hybrid current drive, it can also instruct the design of experiments. (authors)

Numerical analysis on the synergy between electron cyclotron current drive and lower hybrid current drive in tokamak plasmas

International Nuclear Information System (INIS)

Chen, S Y; Hong, B B; Liu, Y; Lu, W; Huang, J; Tang, C J; Ding, X T; Zhang, X J; Hu, Y J

2012-01-01

The synergy between electron cyclotron current drive (ECCD) and lower hybrid current drive (LHCD) is investigated numerically with the parameters of the HL-2A tokamak. Based on the understanding of the synergy mechanisms, a high current driven efficiency or a desired radial current profile can be achieved through properly matching the parameters of ECCD and LHCD due to the flexibility of ECCD. Meanwhile, it is found that the total current driven by the electron cyclotron wave (ECW) and the lower hybrid wave (LHW) simultaneously can be smaller than the sum of the currents driven by the ECW and LHW separately, when the power of the ECW is much larger than the LHW power. One of the reasons leading to this phenomenon (referred to as negative synergy in this context) is that fast current-carrying electrons tend to be trapped, when the perpendicular velocity driven by the ECW is large and the parallel velocity decided by the LHW is correspondingly small. (paper)

Hybridization rates between lettuce (Lactuca sativa) and its wild relative (L. serriola) under field conditions.

Science.gov (United States)

D'Andrea, Luigi; Felber, François; Guadagnuolo, Roberto

2008-01-01

Hybridization and introgression between crops and wild relatives may have important evolutionary and ecological consequences such as gene swamping or increased invasiveness. In the present study, we investigated hybridization under field conditions between crop lettuce (Lactuca sativa) and its wild relative prickly lettuce (L. serriola), two cross-compatible, predominantly autogamous and insect pollinated species. In 2003 and 2004, we estimated the rates of hybridization between L. sativa and L. serriola in close-to-reality field experiments carried out in two locations of Northern Switzerland. Seeds set by the experimental wild plants were collected and sown (44 352 in 2003 and 252 345 in 2004). Progeny was screened morphologically for detecting natural hybrids. Prior to the experiment, specific RAPD markers were used to confirm that morphological characters were reliable for hybrid identification. Hybridization occurred up to the maximal distance tested (40 m), and hybridization rates varied between 0 to 26%, decreasing with distance. More than 80% of the wild plants produced at least one hybrid (incidence of hybridization, IH) at 0 m and 1 m. It equaled 4 to 5% at 40 m. In sympatric crop-wild populations, cross-pollination between cultivated lettuce and its wild relative has to be seen as the rule rather than the exception for short distances.

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 ...

Hybridized electronic states in potassium-doped picene probed by soft x-ray spectroscopies

Directory of Open Access Journals (Sweden)

Hiroyuki Yamane

2012-12-01

Full Text Available The electronic structure of the unoccupied and occupied states of potassium (K-doped and undoped picene crystalline films has been investigated by using the element-selective and bulk-sensitive photon-detection methods of X-ray absorption and emission spectroscopies. We observed the formation of the doping-induced unoccupied and occupied electronic states in K-doped picene. By applying the inner-shell resonant-excitation experiments, we observed the evidence for the orbital hybridization between K and picene near the Fermi energy. Furthermore, the resonant X-ray emission experiment suggests the presence of the Raman-active vibronic interaction in K-doped picene. These experimental evidences play a crucial role in the superconductivity of K-doped picene.

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

The analysis of single-electron orbits in a free electron laser based upon a rectangular hybrid wiggler

International Nuclear Information System (INIS)

Kordbacheh, A.; Ghahremaninezhad, Roghayeh; Maraghechi, B.

2012-01-01

A three-dimensional analysis of a novel free-electron laser (FEL) based upon a rectangular hybrid wiggler (RHW) is presented. This RHW is designed in a configuration composed of rectangular rings with alternating ferrite and dielectric spacers immersed in a solenoidal magnetic field. An analytic model of RHW is introduced by solution of Laplace's equation for the magnetostatic fields under the appropriate boundary conditions. The single-electron orbits in combined RHW and axial guide magnetic fields are studied when only the first and the third spatial harmonic components of the RHW field are taken into account and the higher order terms are ignored. The results indicate that the third spatial harmonic leads to group III orbits with a strong negative mass regime particularly in large solenoidal magnetic fields. RHW is found to be a promising candidate with favorable characteristics to be used in microwave FEL.

The analysis of single-electron orbits in a free electron laser based upon a rectangular hybrid wiggler

Science.gov (United States)

Kordbacheh, A.; Ghahremaninezhad, Roghayeh; Maraghechi, B.

2012-09-01

A three-dimensional analysis of a novel free-electron laser (FEL) based upon a rectangular hybrid wiggler (RHW) is presented. This RHW is designed in a configuration composed of rectangular rings with alternating ferrite and dielectric spacers immersed in a solenoidal magnetic field. An analytic model of RHW is introduced by solution of Laplace's equation for the magnetostatic fields under the appropriate boundary conditions. The single-electron orbits in combined RHW and axial guide magnetic fields are studied when only the first and the third spatial harmonic components of the RHW field are taken into account and the higher order terms are ignored. The results indicate that the third spatial harmonic leads to group III orbits with a strong negative mass regime particularly in large solenoidal magnetic fields. RHW is found to be a promising candidate with favorable characteristics to be used in microwave FEL.

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)

Detection of secondary electrons with pixelated hybrid semiconductor detectors

International Nuclear Information System (INIS)

Gebert, Ulrike Sonja

2011-01-01

Within the scope of this thesis, secondary electrons were detected with a pixelated semiconductor detector named Timepix. The Timepix detector consists of electronics and a sensor made from a semiconductor material. The connection of sensor and electronics is done for each pixel individually using bump bonds. Electrons with energies above 3 keV can be detected with the sensor. One electron produces a certain amount of electron-hole pairs according to its energy. The charge then drifts along an electric field to the pixel electronics, where it induces an electric signal. Even without a sensor it is possible to detect an electric signal from approximately 1000 electrons directly in the pixel electronics. Two different detector systems to detect secondary electrons using the Timepix detector were investigated during this thesis. First of all, a hybrid photon detector (HPD) was used to detect single photoelectrons. The HPD consists of a vacuum vessel with an entrance window and a cesium iodine photocathode at the inner surface of the window. Photoelectrons are released from the photocathode by incident light and are accelerated in an electric field towards the Timepix detector, where the point of interaction and the arrival time of the electron is determined. With a proximity focusing setup, a time resolution of 12 ns (with an acceleration voltage of 20 kV between photocathode and Timepix detector) was obtained. The HPD examined in this thesis showed a strong dependence of the dark rate form the acceleration voltage and the pressure in the vacuum vessel. At a pressure of few 10 -5 mbar and an acceleration voltage of 20 kV, the dark rate was about 800 Hz per mm 2 area of the read out photocathode. One possibility to reduce the dark rate is to identify ion feedback events. With a slightly modified setup it was possible to reduce the dark rate to 0.5 Hz/mm 2 . To achieve this, a new photocathode was mounted in a shorter distance to the detector. The measurements where

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

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)

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)

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.

Direct Observation of Electron-Phonon Coupling and Slow Vibrational Relaxation in Organic-Inorganic Hybrid Perovskites

Science.gov (United States)

Hurtado Parra, Sebastian; Straus, Daniel; Iotov, Natasha; Fichera, Bryan; Gebhardt, Julian; Rappe, Andrew; Subotnik, Joseph; Kikkawa, James; Kagan, Cherie

Quantum and dielectric confinement effects in Ruddlesden-Popper 2D hybrid perovskites create excitons with a binding energy exceeding 150 meV. We exploit the large exciton binding energy to study exciton and carrier dynamics as well as electron-phonon coupling (EPC) in hybrid perovskites using absorption and photoluminescence (PL) spectroscopies. At temperatures 75 K, excitonic absorption and PL exhibit homogeneous broadening. While absorption remains homogeneous, PL becomes inhomogeneous at temperatures <75K, which we speculate is caused by the formation and subsequent dynamics of a polaronic exciton. This work is supported by the U.S. Department of Energy, Office of Basic Energy Sciences Grant DE-SC0002158 and the National Science Foundation Graduate Research Fellowship Grant DGE-1321851.

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)

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)

Genetic molecular analysis of Coffea arabica (Rubiaceae hybrids using SRAP markers

Directory of Open Access Journals (Sweden)

Manoj Kumar Mishra

2011-06-01

Full Text Available In Coffea arabica (arabica coffee, the phenotypic as well as genetic variability has been found low because of the narrow genetic basis and self fertile nature of the species. Because of high similarity in phenotypic appearance among the majority of arabica collections, selection of parental lines for inter-varietals hybridization and identification of resultant hybrids at an early stage of plant growth is difficult. DNA markers are known to be reliable in identifying closely related cultivars and hybrids. Sequence Related Amplified Polymorphism (SRAP is a new molecular marker technology developed based on PCR. In this paper, sixty arabica-hybrid progenies belonging to six crosses were analyzed using 31 highly polymorphic SRAP markers. The analysis revealed seven types of SRAP marker profiles which are useful in discriminating the parents and hybrids. The number of bands amplified per primer pair ranges from 6.13 to 8.58 with average number of seven bands. Among six hybrid combinations, percentage of bands shared between hybrids and their parents ranged from 66.29% to 85.71% with polymorphic bands varied from 27.64% to 60.0%. Percentage of hybrid specific fragments obtained in various hybrid combinations ranged from 0.71% to 10.86% and ascribed to the consequence of meiotic recombination. Based on the similarity index calculation, it was observed that F1 hybrids share maximum number of bands with the female parent compared to male parent. The results obtained in the present study revealed the effectiveness of SRAP technique in cultivar identification and hybrid analysis in this coffee species. Rev. Biol. Trop. 59 (2: 607-617. Epub 2011 June 01.

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

Electronic properties of CdWO{sub 4}: Use of hybrid exchange and correlation functionals

Energy Technology Data Exchange (ETDEWEB)

Meena, B. S., E-mail: bsmphysics@gmail.com; Mund, H. S.; Ahuja, B. L. [Department of Physics, University College of Science, M. L. Sukhadia University, Udaipur-313001 (India); Heda, N. L. [Department of Pure and Applied Physics, University of Kota, Kota-324010 (India)

2016-05-23

Energy bands, density of states (DOS), Mulliken population (MP) and electron momentum densities (EMDs) of CdWO{sub 4} are presented using hybrid exchange and correlation functionals namely B3LYP, B3PW and PBE0. To validate the present hybrid potentials, theoretical EMDs have been compared with the experimental Compton profile. It is found that LCAO-B3LYP based Compton profile gives a better agreement with experiment than other theoretical profiles. The energy bands and DOS show a wide band gap semiconducting nature of CdWO{sub 4}. The theoretical band gap obtained using B3LYP scheme reconciles well with the available experimental data. In addition, we have also presented the anisotropies in EMDs along [100], [110] and [001] directions and the bonding effects using the MP data.

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

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.

Temperature Dependent Surface Structures and Electronic Properties of Organic-Inorganic Hybrid Perovskite Single Crystals

Science.gov (United States)

Jao, M.-H.; Teague, M. L.; Huang, J.-S.; Tseng, W.-S.; Yeh, N.-C.

Organic-inorganic hybrid perovskites, arising from research of low-cost high performance photovoltaics, have become promising materials not only for solar cells but also for various optoelectronic and spintronic applications. An interesting aspect of the hybrid perovskites is that their material properties, such as the band gap, can be easily tuned by varying the composition, temperature, and the crystalline phases. Additionally, the surface structure is critically important for their optoelectronic applications. It is speculated that different crystalline facets could show different trap densities, thus resulting in microscopically inhomogeneous performance. Here we report direct studies of the surface structures and electronic properties of hybrid perovskite CH3NH3PbI3 single crystals by scanning tunneling microscopy and spectroscopy (STM/STS). We found long-range spatially homogeneous tunneling conductance spectra with a well-defined energy gap of (1.55 +/- 0.1) eV at 300 K in the tetragonal phase, suggesting high quality of the single crystals. The energy gap increased to (1.81 +/- 0.1) eV in the orthorhombic phase, below the tetragonal-to-orthorhombic phase transition temperature at 150 K. Detailed studies of the temperature evolution in the spatially resolved surface structures and local density of states will be discussed to elucidate how these properties may influence the optoelectronic performance of the hybrid perovskites. We thank the support from NTU in Taiwan and from NSF in the US.

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.

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 ...

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.

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)

Strong Depletion in Hybrid Perovskite p-n Junctions Induced by Local Electronic Doping.

Science.gov (United States)

Ou, Qingdong; Zhang, Yupeng; Wang, Ziyu; Yuwono, Jodie A; Wang, Rongbin; Dai, Zhigao; Li, Wei; Zheng, Changxi; Xu, Zai-Quan; Qi, Xiang; Duhm, Steffen; Medhekar, Nikhil V; Zhang, Han; Bao, Qiaoliang

2018-04-01

A semiconductor p-n junction typically has a doping-induced carrier depletion region, where the doping level positively correlates with the built-in potential and negatively correlates with the depletion layer width. In conventional bulk and atomically thin junctions, this correlation challenges the synergy of the internal field and its spatial extent in carrier generation/transport. Organic-inorganic hybrid perovskites, a class of crystalline ionic semiconductors, are promising alternatives because of their direct badgap, long diffusion length, and large dielectric constant. Here, strong depletion in a lateral p-n junction induced by local electronic doping at the surface of individual CH 3 NH 3 PbI 3 perovskite nanosheets is reported. Unlike conventional surface doping with a weak van der Waals adsorption, covalent bonding and hydrogen bonding between a MoO 3 dopant and the perovskite are theoretically predicted and experimentally verified. The strong hybridization-induced electronic coupling leads to an enhanced built-in electric field. The large electric permittivity arising from the ionic polarizability further contributes to the formation of an unusually broad depletion region up to 10 µm in the junction. Under visible optical excitation without electrical bias, the lateral diode demonstrates unprecedented photovoltaic conversion with an external quantum efficiency of 3.93% and a photodetection responsivity of 1.42 A W -1 . © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Rectification of electronic heat current by a hybrid thermal diode.

Science.gov (United States)

Martínez-Pérez, Maria José; Fornieri, Antonio; Giazotto, Francesco

2015-04-01

Thermal diodes--devices that allow heat to flow preferentially in one direction--are one of the key tools for the implementation of solid-state thermal circuits. These would find application in many fields of nanoscience, including cooling, energy harvesting, thermal isolation, radiation detection and quantum information, or in emerging fields such as phononics and coherent caloritronics. However, both in terms of phononic and electronic heat conduction (the latter being the focus of this work), their experimental realization remains very challenging. A highly efficient thermal diode should provide a difference of at least one order of magnitude between the heat current transmitted in the forward temperature (T) bias configuration (Jfw) and that generated with T-bias reversal (Jrev), leading to ℛ = Jfw/Jrev ≫ 1 or ≪ 1. So far, ℛ ≈ 1.07-1.4 has been reported in phononic devices, and ℛ ≈ 1.1 has been obtained with a quantum-dot electronic thermal rectifier at cryogenic temperatures. Here, we show that unprecedentedly high ratios of ℛ ≈ 140 can be achieved in a hybrid device combining normal metals tunnel-coupled to superconductors. Our approach provides a high-performance realization of a thermal diode for electronic heat current that could be successfully implemented in true low-temperature solid-state thermal circuits.

Three-input gate logic circuits on chemically assembled single-electron transistors with organic and inorganic hybrid passivation layers.

Science.gov (United States)

Majima, Yutaka; Hackenberger, Guillaume; Azuma, Yasuo; Kano, Shinya; Matsuzaki, Kosuke; Susaki, Tomofumi; Sakamoto, Masanori; Teranishi, Toshiharu

2017-01-01

Single-electron transistors (SETs) are sub-10-nm scale electronic devices based on conductive Coulomb islands sandwiched between double-barrier tunneling barriers. Chemically assembled SETs with alkanethiol-protected Au nanoparticles show highly stable Coulomb diamonds and two-input logic operations. The combination of bottom-up and top-down processes used to form the passivation layer is vital for realizing multi-gate chemically assembled SET circuits, as this combination enables us to connect conventional complementary metal oxide semiconductor (CMOS) technologies via planar processes. Here, three-input gate exclusive-OR (XOR) logic operations are demonstrated in passivated chemically assembled SETs. The passivation layer is a hybrid bilayer of self-assembled monolayers (SAMs) and pulsed laser deposited (PLD) aluminum oxide (AlO[Formula: see text]), and top-gate electrodes were prepared on the hybrid passivation layers. Top and two-side-gated SETs showed clear Coulomb oscillation and diamonds for each of the three available gates, and three-input gate XOR logic operation was clearly demonstrated. These results show the potential of chemically assembled SETs to work as logic devices with multi-gate inputs using organic and inorganic hybrid passivation layers.

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.

Landau damping of dust acoustic waves in the presence of hybrid nonthermal nonextensive electrons

Science.gov (United States)

El-Taibany, W. F.; Zedan, N. A.; Taha, R. M.

2018-06-01

Based on the kinetic theory, Landau damping of dust acoustic waves (DAWs) propagating in a dusty plasma composed of hybrid nonthermal nonextensive distributed electrons, Maxwellian distributed ions and negatively charged dust grains is investigated using Vlasov-Poisson's equations. The characteristics of the DAWs Landau damping are discussed. It is found that the wave frequency increases by decreasing (increasing) the value of nonextensive (nonthermal) parameter, q (α ). It is recognized that α plays a significant role in observing damping or growing DAW oscillations. For small values of α , damping modes have been observed until reaching a certain value of α at which ω i vanishes, then a growing mode appears in the case of superextensive electrons. However, only damping DAW modes are observed in case of subextensive electrons. The present study is useful in the space situations where such distribution exists.

Organic electronic materials: Recent advances in the dft description of the ground and excited states using tuned range-separated hybrid functionals

KAUST Repository

Körzdörfer, Thomas

2014-11-18

Density functional theory (DFT) and its time-dependent extension (TD-DFT) are powerful tools enabling the theoretical prediction of the ground- and excited-state properties of organic electronic materials with reasonable accuracy at affordable computational costs. Due to their excellent accuracy-to-numerical-costs ratio, semilocal and global hybrid functionals such as B3LYP have become the workhorse for geometry optimizations and the prediction of vibrational spectra in modern theoretical organic chemistry. Despite the overwhelming success of these out-of-the-box functionals for such applications, the computational treatment of electronic and structural properties that are of particular interest in organic electronic materials sometimes reveals severe and qualitative failures of such functionals. Important examples include the overestimation of conjugation, torsional barriers, and electronic coupling as well as the underestimation of bond-length alternations or excited-state energies in low-band-gap polymers.In this Account, we highlight how these failures can be traced back to the delocalization error inherent to semilocal and global hybrid functionals, which leads to the spurious delocalization of electron densities and an overestimation of conjugation. The delocalization error for systems and functionals of interest can be quantified by allowing for fractional occupation of the highest occupied molecular orbital. It can be minimized by using long-range corrected hybrid functionals and a nonempirical tuning procedure for the range-separation parameter.We then review the benefits and drawbacks of using tuned long-range corrected hybrid functionals for the description of the ground and excited states of π-conjugated systems. In particular, we show that this approach provides for robust and efficient means of characterizing the electronic couplings in organic mixed-valence systems, for the calculation of accurate torsional barriers at the polymer limit, and for the

Occurrence of metaxenia and false hybrids in Brassica juncea L. cv. Kikarashina × B. napus

Science.gov (United States)

Tsuda, Mai; Konagaya, Ken-ichi; Okuzaki, Ayako; Kaneko, Yukio; Tabei, Yutaka

2011-01-01

Imported genetically modified (GM) canola (Brassica napus) is approved by Japanese law. Some GM canola varieties have been found around importation sites, and there is public concern that these may have any harmful effects on related species such as reduction of wild relatives. Because B. juncea is distributed throughout Japan and is known to be high crossability with B. napus, it is assumed to be a recipient of B. napus. However, there are few reports for introgression of cross-combination in B. juncea × B. napus. To assess crossability, we artificially pollinated B. juncea with B. napus. After harvesting a large number of progeny seeds, we observed false hybrids and metaxenia of seed coats. Seed coat color was classified into four categories and false hybrids were confirmed by morphological characteristics and random amplified polymorphic DNA (RAPD) markers. Furthermore, the occurrence of false hybrids was affected by varietal differences in B. napus, whereas that of metaxenia was related to hybridity. Therefore, we suggest that metaxenia can be used as a marker for hybrid identification in B. juncea L. cv. Kikarashina × B. napus. Our results suggest that hybrid productivity in B. juncea × B. napus should not be evaluated by only seed productivity, crossability ought to be assessed the detection of true hybrids. PMID:23136472

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.

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.

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)

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.

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

Donor–acceptor graphene-based hybrid materials facilitating photo-induced electron-transfer reactions

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Anastasios Stergiou

2014-09-01

Full Text Available Graphene research and in particular the topic of chemical functionalization of graphene has exploded in the last decade. The main aim is to increase the solubility and thereby enhance the processability of the material, which is otherwise insoluble and inapplicable for technological applications when stacked in the form of graphite. To this end, initially, graphite was oxidized under harsh conditions to yield exfoliated graphene oxide sheets that are soluble in aqueous media and amenable to chemical modifications due to the presence of carboxylic acid groups at the edges of the lattice. However, it was obvious that the high-defect framework of graphene oxide cannot be readily utilized in applications that are governed by charge-transfer processes, for example, in solar cells. Alternatively, exfoliated graphene has been applied toward the realization of some donor–acceptor hybrid materials with photo- and/or electro-active components. The main body of research regarding obtaining donor–acceptor hybrid materials based on graphene to facilitate charge-transfer phenomena, which is reviewed here, concerns the incorporation of porphyrins and phthalocyanines onto graphene sheets. Through illustrative schemes, the preparation and most importantly the photophysical properties of such graphene-based ensembles will be described. Important parameters, such as the generation of the charge-separated state upon photoexcitation of the organic electron donor, the lifetimes of the charge-separation and charge-recombination as well as the incident-photon-to-current efficiency value for some donor–acceptor graphene-based hybrids, will be discussed.

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

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…

Determination of the energy of suprathermal electrons during lower hybrid current drive on PBX-M

International Nuclear Information System (INIS)

von Goeler, S.; Bernabei, S.; Davis, W.; Ignat, D.; Kaita, R.; Roney, P.; Stevens, J.; Post-Zwicker, A.

1993-06-01

Suprathermal electrons are diagnosed by a hard x-ray pinhole camera during lower hybrid current drive on PBX-M. The experimental hard x-ray images are compared with simulated images, which result from an integration of the relativistic bremsstrahlung along lines-of-sight through the bean-shaped plasma. Images with centrally peaked and radially hollow radiation profiles are easily distinguished. The energy distribution of the suprathermal electrons is analyzed by comparing images taken with different absorber foils. An effective photon temperature is derived from the experimental images, and a comparison with simulated photon temperatures yields the energy of the suprathermal electrons. The analysis indicates that the energy of the suprathermal electrons in the hollow discharges is in the 50 to 100 key range in the center of the discharge. There seems to exist a very small higher energy component close to the plasma edge

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

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.

Reação de híbridos, linhagens e progênies de pimentão à requeima causada por Phytophthora capsici e ao mosaico amarelo causado por Pepper yellow mosaic vírus (PepYMV Reaction of hybrids, lines and progenies of sweet pepper the blight caused by Phytophthora capsici and to Pepper yellow mosaic virus (PepYMV

Directory of Open Access Journals (Sweden)

Ildon Rodrigues do Nascimento

2007-02-01

. PIM-013 e MYR-29 são fontes de resistência promissoras a P. capsici PepYMV, respectivamente, para serem utilizadas no desenvolvimento de híbridos com resistência a esses patógenos.Resistance to pepper blight induced by Phytophthora capsici and to yellow mosaic caused by a potyvirus species (PepYMV are two priorities of most pepper (Capsicum annuum L. breeding programmes in Brazil. The reactions of three commercial hybrids (Magali-R, Atenas F1, and Fortuna Super F1 to both P. capsici and PepYMV was studied, along with those of 20 experimental hybrids, 6 inbred lines and two F2:4 progenies from the Universidade Federal of Lavras pepper breeding programme. Trials in randomized complete block designs were carried out independently for each of the pathogens, with four and two replications, respectively. Each replications comprised 8 plants in 128-cell speeding styrofoam trays, kept in plastic-covered greenhouses protected with screen at the sides. Evaluation of symptoms was made from the 4th to the 14th and from the 15 th to the 40th day after inoculation (DAI for P. capsici and PepYMV, respectively. Inoculation with P. capsici was made by dispensing 5mL of a 10(4 zoospore.mL-1 solution at the soil around the base of each plant. PepYMV was mechanically inoculated from extracts of previously infected leaves of TNN tobacco. Hybrids Magali-R and Fortuna Super were susceptible to P. capsici, while the hybrid Atenas, the access Criollo de Morellos 334, the progeny PIX-030 pl#03-2 and PIX-030 pl#06-3 (both originated from crosses with Criollo de Morellos, and the line PIM-013 were resistant. Among the experimental hybrids, three were also resistant to P. capsici, all three having PIM-013 as one of the parental lines. Resistance to PepYMV was found in Criollo de Morellos 334, progeny PIX-030 pl#03-2 and PIX-030 pl#06-3, and in the commercial hybrid Magali, besides 6 other experimental hybrids having line MYR-29 as one of the parental ines. The only treatment with resistance

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)

Two-stream instabilities from the lower-hybrid frequency to the electron cyclotron frequency: application to the front of quasi-perpendicular shocks

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L. Muschietti

2017-09-01

Full Text Available Quasi-perpendicular supercritical shocks are characterized by the presence of a magnetic foot due to the accumulation of a fraction of the incoming ions that is reflected by the shock front. There, three different plasma populations coexist (incoming ion core, reflected ion beam, electrons and can excite various two-stream instabilities (TSIs owing to their relative drifts. These instabilities represent local sources of turbulence with a wide frequency range extending from the lower hybrid to the electron cyclotron. Their linear features are analyzed by means of both a dispersion study and numerical PIC simulations. Three main types of TSI and correspondingly excited waves are identified: i. Oblique whistlers due to the (so-called fast relative drift between reflected ions/electrons; the waves propagate toward upstream away from the shock front at a strongly oblique angle (θ ∼ 50° to the ambient magnetic field Bo, have frequencies a few times the lower hybrid, and have wavelengths a fraction of the ion inertia length c∕ωpi. ii. Quasi-perpendicular whistlers due to the (so-called slow relative drift between incoming ions/electrons; the waves propagate toward the shock ramp at an angle θ a few degrees off 90°, have frequencies around the lower hybrid, and have wavelengths several times the electron inertia length c∕ωpe. iii. Extended Bernstein waves which also propagate in the quasi-perpendicular domain, yet are due to the (so-called fast relative drift between reflected ions/electrons; the instability is an extension of the electron cyclotron drift instability (normally strictly perpendicular and electrostatic and produces waves with a magnetic component which have frequencies close to the electron cyclotron as well as wavelengths close to the electron gyroradius and which propagate toward upstream. Present results are compared with previous works in order to stress some features not previously analyzed and to define a more

Radially localized measurements of superthermal electrons using oblique electron cyclotron emission

International Nuclear Information System (INIS)

Preische, S.; Efthimion, P.C.; Kaye, S.M.

1996-05-01

It is shown that radial localization of optically tin Electron Cyclotron Emission from superthermal electrons can be imposed by observation of emission upshifted from the thermal cyclotron resonance in the horizontal midplane of a tokamak. A new and unique diagnostic has been proposed and operated to make radially localized measurements of superthermal electrons during Lower Hybrid Current Drive on the PBX-M tokamak. The superthermal electron density profile as well as moments of the electron energy distribution as a function of radius are measured during Lower Hybrid Current Drive. The time evolution of these measurements after the Lower Hybrid power is turned off are given and the observed behavior reflects the collisional isotropization of the energy distribution and radial diffusion of the spatial profile

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.)

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.

The Effect of Altered Soil Moisture on Hybridization Rate in a Crop-Wild System (Raphanus spp..

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Lesley G Campbell

Full Text Available Since plant mating choices are flexible and responsive to the environment, rates of spontaneous hybridization may vary across ecological clines. Developing a robust and predictive framework for rates of plant gene flow requires assessing the role of environmental sensitivity on plant reproductive traits, relative abundance, and pollen vectors. Therefore, across a soil moisture gradient, we quantified pollinator movement, life-history trait variation, and unidirectional hybridization rates from crop (Raphanus sativus to wild (Raphanus raphanistrum radish populations. Both radish species were grown together in relatively dry (no rain, relatively wet (double rain, or control soil moisture conditions in Ohio, USA. We measured wild and crop radish life-history, phenology and pollinator visitation patterns. To quantify hybridization rates from crop-to-wild species, we used a simply inherited morphological marker to detect F1 hybrid progeny. Although crop-to-wild hybridization did not respond to watering treatments, the abundance of hybrid offspring was higher in fruits produced late in the period of phenological overlap, when both species had roughly equal numbers of open flowers. Therefore, the timing of fruit production and its relationship to flowering overlap may be more important to hybrid zone formation in Raphanus spp. than soil moisture or pollen vector movements.

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.

ORNL TNS program: microwave start-up of tokamak plasmas near electron cyclotron and upper hybrid resonances

International Nuclear Information System (INIS)

Peng, Y.K.M.; Borowski, S.K.

1977-12-01

The scenario of toroidal plasma start-up with microwave initiation and heating near the electron cyclotron frequency is suggested and examined here. We assume microwave irradiation from the high field side and an anomalously large absorption of the extraordinary waves near the upper hybrid resonance. The dominant electron energy losses are assumed to be due to magnetic field curvature and parallel drifts, ionization of neutrals, cooling by ions, and radiation by low Z impurities. It is shown by particle and energy balance considerations that electron temperatures around 250 eV and densities of 10 12 to 10 13 cm -3 can be maintained, at least in a narrow region near the upper hybrid resonance, with modest microwave powers in the Impurity Study Experiment (ISX) (120 kW at 28 GHz) and The Next Step (TNS) (0.57 MW at 120 GHz). The loop voltages required for start-up from these initial plasmas are also estimated. It is shown that the loop voltage can be reduced by a factor of five to ten from that for unassisted start-up without an increase in the resistive loss in volt-seconds. If this reduction in loop voltage is verified in the ISX experiments, substantial savings in the cost of power supplies for the ohmic heating (OH) and equilibrium field (EF) coils can be realized in future large tokamaks

Electronic traffic signs: The interplay between hybrid and full matrix e-signs

Energy Technology Data Exchange (ETDEWEB)

Lucas-Alba, A.; Hernando Mazon, A.; Blanch Mico, A.M.; Gutierrez Perez, D.; Echeverria Villaspi, J.I.; Landa Tejero-Garces, N.

2016-07-01

Road signs constitute a complex and growing communication system where different elements (pictograms, shapes, texts, etc.) are combined following different strategies. In this paper we have confronted drivers with a number of messages (congestion or road works, before, between, after location/s) developed as an adaptation of Advance Location Signs (class G, 1c in the 1968 Convention) to electronic displays. We manipulate two main factors a) the reading strategy (top-down vs. bottom-up) and the type of matrix display (hybrid, dissociating pictogram and text, vs. full matrix), in a repeated measures experimental design. The time taken to answer and the response given (correct, incorrect) was measured for each of the 24 message-blocks. Results show that the organization of the elements displayed is a key determinant for driver comprehension. Further thoughts on the need to understand the interplay between the formats adopted by static vs electronic message signs are provided. (Author)

Modeling of the electron distribution based on bremsstrahlung emission during lower hybrid current drive on PLT

Energy Technology Data Exchange (ETDEWEB)

Stevens, J.E.; von Goeler, S.; Bernabei, S.; Bitter, M.; Chu, T.K.; Efthimion, P.; Fisch, N.; Hooke, W.; Hosea, J.; Jobes, F.

1985-03-01

Lower hybrid current drive requires the generation of a high energy electron tail anisotropic in velocity. Measurements of bremsstrahlung emission produced by this tail are compared with the calculated emission from reasonable model distributions. The physical basis and the sensitivity of this modeling process are described and the plasma properties of current driven discharges which can be derived from the model are discussed.

Modeling of the electron distribution based on bremsstrahlung emission during lower hybrid current drive on PLT

International Nuclear Information System (INIS)

Stevens, J.E.; von Goeler, S.; Bernabei, S.

1985-03-01

Lower hybrid current drive requires the generation of a high energy electron tail anisotropic in velocity. Measurements of bremsstrahlung emission produced by this tail are compared with the calculated emission from reasonable model distributions. The physical basis and the sensitivity of this modeling process are described and the plasma properties of current driven discharges which can be derived from the model are discussed

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.

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)

Genetic analysis of post-mating reproductive barriers in hybridizing European Populus species.

Science.gov (United States)

Macaya-Sanz, D; Suter, L; Joseph, J; Barbará, T; Alba, N; González-Martínez, S C; Widmer, A; Lexer, C

2011-10-01

Molecular genetic analyses of experimental crosses provide important information on the strength and nature of post-mating barriers to gene exchange between divergent populations, which are topics of great interest to evolutionary geneticists and breeders. Although not a trivial task in long-lived organisms such as trees, experimental interspecific recombinants can sometimes be created through controlled crosses involving natural F(1)'s. Here, we used this approach to understand the genetics of post-mating isolation and barriers to introgression in Populus alba and Populus tremula, two ecologically divergent, hybridizing forest trees. We studied 86 interspecific backcross (BC(1)) progeny and >350 individuals from natural populations of these species for up to 98 nuclear genetic markers, including microsatellites, indels and single nucleotide polymorphisms, and inferred the origin of the cytoplasm of the cross with plastid DNA. Genetic analysis of the BC(1) revealed extensive segregation distortions on six chromosomes, and >90% of these (12 out of 13) favored P. tremula donor alleles in the heterospecific genomic background. Since selection was documented during early diploid stages of the progeny, this surprising result was attributed to epistasis, cyto-nuclear coadaptation, heterozygote advantage at nuclear loci experiencing introgression or a combination of these. Our results indicate that gene flow across 'porous' species barriers affects these poplars and aspens beyond neutral, Mendelian expectations and suggests the mechanisms responsible. Contrary to expectations, the Populus sex determination region is not protected from introgression. Understanding the population dynamics of the Populus sex determination region will require tests based on natural interspecific hybrid zones.

Highly transparent, low-haze, hybrid cellulose nanopaper as electrodes for flexible electronics

KAUST Repository

Xu, Xuezhu

2016-06-01

Paper is an excellent candidate to replace plastics as a substrate for flexible electronics due to its low cost, renewability and flexibility. Cellulose nanopaper (CNP), a new type of paper made of nanosized cellulose fibers, is a promising substrate material for transparent and flexible electrodes due to its potentially high transparency and high mechanical strength. Although CNP substrates can achieve high transparency, they are still characterized by high diffuse transmittance and small direct transmittance, resulting in high optical haze of the substrates. In this study, we proposed a simple methodology for large-scale production of high-transparency, low-haze CNP comprising both long cellulose nanofibrils (CNFs) and short cellulose nanocrystals (CNCs). By varying the CNC/CNF ratio in the hybrid CNP, we could tailor its total transmittance, direct transmittance and diffuse transmittance. By increasing the CNC content, the optical haze of the hybrid CNP could be decreased and its transparency could be increased. The direct transmittance and optical haze of the CNP were 75.1% and 10.0%, respectively, greatly improved from the values of previously reported CNP (31.1% and 62.0%, respectively). Transparent, flexible electrodes were fabricated by coating the hybrid CNP with silver nanowires (AgNWs). The electrodes showed a low sheet resistance (minimum 1.2 Ω sq-1) and a high total transmittance (maximum of 82.5%). The electrodes were used to make a light emitting diode (LED) assembly to demonstrate their potential use in flexible displays. © 2016 The Royal Society of Chemistry.

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.

Performance of cotton leaf curl virus resistant intrahirsutum f/sub 1/ hybrids

International Nuclear Information System (INIS)

Baloch, M.J.

2004-01-01

The first and foremost effort to combat the devastating cotton leaf curl virus (clcv) disease would be to utilize those clcv resistant germplasm in a hybridization programme which can enhance the possibilities of selecting desirable progenies from segregating populations. In this connection, 16 clcv intrahirsutum F1 hybrids were developed and evaluated for their performance. The hybrids, on an average gave an increase of 26.02 % in seed cotton yield; 11.52 % in bolls per plant; 14.23 % in boll weight; 4.28 % in lint; 3.89 % in fibre length and 8.21 % in earliness against the average of parents. However, among the hybrids, the top three scoring for yield were, BH.121 x Cyto.9/91, Cyto.9/91 x CRIS-226 and VH-137 x CRIS-226. The number of bolls per plant was found to be a major contributing factor for increased yield because the hybrids which set higher bolls correspondingly gave higher yields. Boll weight was not regarded as an important attribute to increase yield because hybrids with moderate boll sizes were among the top three high yielders. For lint %, the hybrids CRIS-129 x LRA-5166 and FH-901 x VH-137 were first for fibre length, whereas CRIS-121 x Cyto.51 and BH-124 x CIM-448 were among the top two rankers. Regarding earliness, the hybrids CRIS-121 x Cyto. 51 gave the highest boll opening percent and next in order was the hybrid VH-137 x DNH-49. Our results thus generally suggest that although the best three hybrids were desirable for other traits, the choice of the hybrids may be made on the priority for characters to be bred. (author)

Measurement of lower-hybrid-driven current profile by Abel inversion of electron-cyclotron wave transmission spectra

International Nuclear Information System (INIS)

Fidone, I.; Giruzzi, G.; Caron, X.; Meyer, R.L.

1991-01-01

A method for measuring the radial profile of the lower-hybrid-driven current in a low-density tokamak plasma using electron-cyclotron wave attenuation is discussed. This diagnostic scheme is reminiscent of the transmission interferometry approach, commonly used in tokamaks to measure the plasma density, but now the wave amplitude instead of the phase is measured. Wave attenuation of the ordinary mode at ω p much-lt ω c along vertical chords is measured; at these frequencies, the waves are absorbed by the superthermal tail sustained by lower-hybrid waves and the local wave absorption coefficient is proportional to the noninductive current density. The radial profile of this current is obtained from Abel inversion. An application to the Tore Supra tokamak is presented

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

Genomic Characterization of Interspecific Hybrids and an Admixture Population Derived from Panicum amarum × P. virgatum

Directory of Open Access Journals (Sweden)

Christopher Heffelfinger

2015-07-01

Full Text Available Switchgrass ( L. and its relatives are regarded as top bioenergy crop candidates; however, one critical barrier is the introduction of useful genetic diversity and the development of new cultivars and hybrids. Combining genomes from related cultivars and species provides an opportunity to introduce new traits. In switchgrass, a breeding advantage would be achieved by combining the genomes of intervarietal ecotypes or interspecific hybrids. The recovery of wide crosses, however, is often tedious and may involve complicated embryo rescue and numerous backcrosses. Here, we demonstrate a straightforward approach to wide crosses involving the use of a selectable transgene for recovery of interspecific [ cv. Alamo × Ell var or Atlantic Coastal Panicgrass (ACP] F hybrids followed by backcrossing to generate a nontransgenic admixture population. A nontransgenic herbicide-sensitive (HbS admixture population of 83 FBC progeny was analyzed by genotyping-by-sequencing (GBS to characterize local ancestry, parental contribution, and patterns of recombination. These results demonstrate a widely applicable breeding strategy that makes use of transgenic selectable resistance to identify and recover true hybrids.

Role of electron back action on photons in hybridizing double-layer graphene plasmons with localized photons

Science.gov (United States)

Huang, Danhong; Iurov, Andrii; Gumbs, Godfrey

2018-05-01

In this paper, we deal with the electromagnetic coupling between an incident surface-plasmon-polariton wave and relativistic electrons in two graphene layers. Our previous investigation was limited to single-layer graphene (Iurov et al 2017 Phys. Rev. B 96 081408). However, the present work, is both an expanded and extended version of this previous Phys. Rev. B paper after having included very detailed theoretical formalisms and extensive comparisons of results from either one or two graphene layers embedded in a dielectric medium. The additional retarded Coulomb interaction between two graphene layers will compete with the coupling between the single graphene layer and the surface of a conductor. Consequently, some distinctive features, such as triply-hybridized absorption peaks and a new acoustic-like graphene plasmon mode within the anticrossing region, have been found for the double-layer graphene system. Physically, our theory is self-consistent, in comparison with a commonly adopted perturbative theory, for studying hybrid light-plasmon modes and the electron back action on photons. Instead of usual radiation or grating-deflection field coupling, a surface-plasmon-polariton localized field coupling is introduced with completely different dispersion relations for radiative (small wave numbers) and evanescent (large wave numbers) field modes. Technically, the exactly calculated effective scattering matrix for this theory can be employed to construct an effective-medium theory in order to improve the accuracy of the well-known finite-difference time-domain method for solving Maxwell’s equations numerically. Practically, the predicted triply-hybridized absorption peaks can excite polaritons only, giving rise to a possible polariton-condensation based laser.

Power sources for portable electronics and hybrid cars: lithium batteries and fuel cells.

Science.gov (United States)

Scrosati, Bruno

2005-01-01

The activities in progress in our laboratory for the development of batteries and fuel cells for portable electronics and hybrid car applications are reviewed and discussed. In the case of lithium batteries, the research has been mainly focused on the characterization of new electrode and electrolyte materials. Results related to disordered carbon anodes and improved, solvent-free, as well as gel-type, polymer electrolytes are particularly stressed. It is shown that the use of proper gel electrolytes, in combination with suitable electrode couples, allows the development of new types of safe, reliable, and low-cost lithium ion batteries which appear to be very promising power sources for hybrid vehicles. Some of the technologies proven to be successful in the lithium battery area are readapted for use in fuel cells. In particular, this approach has been followed for the preparation of low-cost and stable protonic membranes to be proposed as an alternative to the expensive, perfluorosulfonic membranes presently used in polymer electrolyte membrane fuel cells (PEMFCs). Copyright 2005 The Japan Chemical Journal Forum and Wiley Periodicals, Inc

Implications of orbital hybridization on the electronic properties of doped quantum dots: the case of Cu:CdSe

Science.gov (United States)

Wright, Joshua T.; Forsythe, Kyle; Hutchins, Jamie; Meulenberg, Robert W.

2016-04-01

This paper investigates how chemical dopants affect the electronic properties of CdSe quantum dots (QDs) and why a model that incorporates the concepts of orbital hybridization must be used to understand these properties. Extended X-ray absorption fine structure spectroscopy measurements show that copper dopants in CdSe QDs occur primarily through a statistical doping mechanism. Ultraviolet photoemission spectroscopy (UPS) experiments provide a detailed insight on the valence band (VB) structure of doped and undoped QDs. Using UPS measurements, we are able to observe photoemission from the Cu d-levels above VB maximum of the QDs which allows a complete picture of the energy band landscape of these materials. This information provides insights into many of the physical properties of doped QDs, including the highly debated near-infrared photoluminescence in Cu doped CdSe QDs. We show that all our results point to a common theme of orbital hybridization in Cu doped CdSe QDs which leads to optically and electronically active states below the conduction band minimum. Our model is supported from current-voltage measurements of doped and undoped materials, which exhibit Schottky to Ohmic behavior with Cu doping, suggestive of a tuning of the lowest energy states near the Fermi level.This paper investigates how chemical dopants affect the electronic properties of CdSe quantum dots (QDs) and why a model that incorporates the concepts of orbital hybridization must be used to understand these properties. Extended X-ray absorption fine structure spectroscopy measurements show that copper dopants in CdSe QDs occur primarily through a statistical doping mechanism. Ultraviolet photoemission spectroscopy (UPS) experiments provide a detailed insight on the valence band (VB) structure of doped and undoped QDs. Using UPS measurements, we are able to observe photoemission from the Cu d-levels above VB maximum of the QDs which allows a complete picture of the energy band landscape of

An improved embryo-rescue protocol for hybrid progeny from seedless Vitis vinifera grapes × wild Chinese Vitis species.

Science.gov (United States)

Li, Gui Rong; Ji, Wei; Wang, Gang; Zhang, Jian Xia; Wang, Yue Jin

A highly efficient technique of embryo rescue is critical when using stenospermocarpic Vitis vinifera cultivars (female parents) to breed novel, disease-resistant, seedless grape cultivars by hybridizing with wild Chinese Vitis species (male parents) having many disease-resistance alleles. The effects of various factors on the improvement of embryo formation, germination, and plantlet development for seven hybrid combinations were studied. The results indicated that Beichun and Shuangyou were the best male parents. The best sampling time for ovule inoculation differed among the female parents. When hybrid ovules were cultured on a double-phase medium with five different solid medium types, percent embryo formation was highest (11.3-28.3%) on a modified MM3 medium. Percentages of embryo germination (15.4-55.4%) and plantlet development (11.15-44.6%) were all highest when embryos were cultured on Woody Plant Medium + 5.7 μM indole-3-acetic acid + 4.4 μM 6-benzylaminopurine + 1.4 μM gibberellic acid + 2% sucrose + 0.05% casein hydrolysate + 0.3% activated charcoal + 0.7% agar. In the absence of other amino acids, the addition of proline significantly increased embryo formation (36.1%), embryo germination (64.6%), and plantlet development (90.5%). A highly efficient protocol has been developed for hybrid embryo rescue from seedless V. vinifera grapes × wild Chinese Vitis species that results in a significant improvement in breeding efficiency for new disease-resistant seedless grapes.

Measurement and modelling of suprathermal electron bursts generated in front of a lower hybrid antenna

Czech Academy of Sciences Publication Activity Database

Gunn, J. P.; Fuchs, Vladimír; Petržílka, Václav; Ekedahl, A.; Fedorczak, N.; Goniche, M.; Hillairet, J.

2016-01-01

Roč. 56, č. 3 (2016), č. článku 036004. ISSN 0029-5515 R&D Projects: GA MŠk(CZ) LM2011021 Institutional support: RVO:61389021 Keywords : lower hybrid * scrape off layer * SOL turbulence * Landau damping * suprathermal electrons Subject RIV: BL - Plasma and Gas Discharge Physics OBOR OECD: Fluids and plasma physics (including surface physics) Impact factor: 3.307, year: 2016 http://iopscience.iop.org/article/10.1088/0029-5515/56/3/036004

High-current electron beam coupling to hybrid waveguide and plasma modes in a dielectric Cherenkov maser with a plasma layer

International Nuclear Information System (INIS)

Shlapakovski, Anatoli S.

2002-01-01

The linear theory of a dielectric Cherenkov maser with a plasma layer has been developed. The dispersion relation has been derived for the model of infinitely thin, fully magnetized, monoenergetic hollow electron beam, in the axisymmetric case. The results of the numerical solution of the dispersion relation and the analysis of the beam coupling to hybrid waves, both hybrid waveguide and hybrid plasma modes, are presented. For the hybrid waveguide mode, spatial growth rate dependences on frequency at different plasma densities demonstrate improvement in gain for moderate densities, but strong shifting the amplification band and narrowing the bandwidth. For the hybrid plasma mode, the case of mildly relativistic, 200-250 keV beams is of interest, so that the wave phase velocity is just slightly greater than the speed of light in a dielectric medium. It has been shown that depending on beam and plasma parameters, the hybrid plasma mode can be separated from the hybrid waveguide mode, or be coupled to it through the beam resulting in strong gain increase, or exhibit a flat gain vs frequency dependence over a very broad band. The parameters, at which the -3 dB bandwidth calculated for 30 dB peak gain exceeds an octave, have been found

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)

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).

Study in electron microscopy of the formation of the hybrid layer using adhesive systems One Coat and Experimental (EXL 759), at the Facultad de Odontologia of the Universidad de Costa Rica

International Nuclear Information System (INIS)

Santamaria Guzman, S. Marcela; Guevara Lopez, Rodrigo

2012-01-01

The formation of the hybrid layer is observed in dental pieces in vitro, utilizing conventional adhesives systems and of self etching with different times of acid etching, by applying of electron microscopy. Samples of dental pieces are prepared utilizing conventional adhesive systems as Single Bond 2 of 3M, One Coat of Coltene and the adhesive self etching Experimental (EXL 759) of 3M. Samples of dental pieces collected have been molars recently extracted and later stored in jars with water. Samples prepared with the adhesive systems are observed in the electron microscope to obtain images of the hybrid layers formed. The hybrid layers formed are compared observing the photographs of the images obtained in the electron microscope. The adhesive system that has allowed the formation of a hybrid layer more convenient is determined. The time of acid etching is determined and has interfered in the formation of a hybrid layer more stable [es

Current-drive and plasma formation experiments on the Versator-II tokamak using lower-hybrid and electron-cyclotron waves

International Nuclear Information System (INIS)

Colborn, J.A.

1992-01-01

During lower-hybrid current-driven (LHCD) tokamak discharges with thermal electron temperature T e ∼ 150 eV, a two-parallel-temperature tail is observed in the electron distribution function. The cold tail extends to parallel energy E parallel ∼ 4.5 keV with temperature T cold tail ∼ 1.5 keV, and the hot tail extends to E parallel > 150 keV with T hot tail > 40 keV. Fokker-Planck computer simulations suggest the cold tail is created by low power, high-N parallel sidelobes in the lower-hybrid antenna spectrum, and that these sidelobes bridge the spectral gap, enabling current drive on small tokamaks such as Versator. During plasma-formation experiments using 28 GHz electroncyclotron (EC) waves, the plasma is born near the EC layer, then moves toward the upper-hybrid (UH) layer within 100-200μs. Wave power is detected in the plasma with frequency f = 300 MHz. Measured turbulent plasma fluctuations are correlated with decay-wave amplitude. Electron-cyclotron current-drive (ECCD) is observed with loop voltage V loop ≤ 0 and fully sustained plasma current I p approx-lt 15 kA at densities up to [n e ] = 2 x 10 12 cm -3 . The efficiency falls rapidly to zero as the density is raised, suggesting the ECCD depends on low collisonality. The EC waves enhance magnetic turbulence in the frequency range 50 kHz approx-lt f approx-lt 400 kHz by up to an order of magnitude. The time-of-arrival of the turbulence to probes at the plasma boundary is longer when the EC layer is farther from the probes

Estimates for Genetic Variance Components in Reciprocal Recurrent Selection in Populations Derived from Maize Single-Cross Hybrids

Directory of Open Access Journals (Sweden)

Matheus Costa dos Reis

2014-01-01

Full Text Available This study was carried out to obtain the estimates of genetic variance and covariance components related to intra- and interpopulation in the original populations (C0 and in the third cycle (C3 of reciprocal recurrent selection (RRS which allows breeders to define the best breeding strategy. For that purpose, the half-sib progenies of intrapopulation (P11 and P22 and interpopulation (P12 and P21 from populations 1 and 2 derived from single-cross hybrids in the 0 and 3 cycles of the reciprocal recurrent selection program were used. The intra- and interpopulation progenies were evaluated in a 10×10 triple lattice design in two separate locations. The data for unhusked ear weight (ear weight without husk and plant height were collected. All genetic variance and covariance components were estimated from the expected mean squares. The breakdown of additive variance into intrapopulation and interpopulation additive deviations (στ2 and the covariance between these and their intrapopulation additive effects (CovAτ found predominance of the dominance effect for unhusked ear weight. Plant height for these components shows that the intrapopulation additive effect explains most of the variation. Estimates for intrapopulation and interpopulation additive genetic variances confirm that populations derived from single-cross hybrids have potential for recurrent selection programs.

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.

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...

Lower hybrid heating data on the Wega experiment revisited using ion stochastic heating and electron Landau damping theories

International Nuclear Information System (INIS)

Gormezano, C.; Hess, W.; Ichtchenko, G.

1980-07-01

The already obtained data on the Wega Tokamak by lower hybrid heating (f=500 MHz - Psub(HF)=130 KW) are revisited in the light of recent theories on ion stochastic heating and quasi-linear electron Landau damping. It is possible to correctly estimate with these theories the fast ion mean energy, the H.F. power density coupled to the ions and that coupled to the electrons. The values of the parallel index of refraction, Nsub(//), which are necessary to obtain a good quantitative agreement between experiment and theoretical estimates, are the same for the ions and for the electrons, even though at higher values than expected

Design of a hybrid double-sideband/single-sideband (schlieren) objective aperture suitable for electron microscopy

Energy Technology Data Exchange (ETDEWEB)

Buijsse, Bart; Laarhoven, Frank M.H.M. van [FEI Company, PO Box 80066, 5600 KA Eindhoven (Netherlands); Schmid, Andreas K.; Cambie, Rossana; Cabrini, Stefano; Jin, Jian [Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States); Glaeser, Robert M., E-mail: rmglaeser@lbl.gov [Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States)

2011-12-15

A novel design is described for an aperture that blocks a half-plane of the electron diffraction pattern out to a desired scattering angle, and then - except for a narrow support beam - transmits all of the scattered electrons beyond that angle. Our proposed tulip-shaped design is thus a hybrid between the single-sideband (ssb) aperture, which blocks a full half-plane of the diffraction pattern, and the conventional (i.e. fully open) double-sideband (dsb) aperture. The benefits of this hybrid design include the fact that such an aperture allows one to obtain high-contrast images of weak-phase objects with the objective lens set to Scherzer defocus. We further demonstrate that such apertures can be fabricated from thin-foil materials by milling with a focused ion beam (FIB), and that such apertures are fully compatible with the requirements of imaging out to a resolution of at least 0.34 nm. As is known from earlier work with single-sideband apertures, however, the edge of such an aperture can introduce unwanted, electrostatic phase shifts due to charging. The principal requirement for using such an aperture in a routine data-collection mode is thus to discover appropriate materials, protocols for fabrication and processing and conditions of use such that the hybrid aperture remains free of charging over long periods of time. -- Highlights: Black-Right-Pointing-Pointer New objective-aperture design is proposed for imaging weak-phase objects. Black-Right-Pointing-Pointer Design produces single-sideband contrast at low spatial frequencies. Black-Right-Pointing-Pointer Design also retains Scherzer-defocus phase contrast at higher resolution. Black-Right-Pointing-Pointer Proof-of-concept results are presented for microfabricated apertures. Black-Right-Pointing-Pointer Charging of such apertures during use remains an experimental challenge.

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)

Genomic islands of differentiation in two songbird species reveal candidate genes for hybrid female sterility.

Science.gov (United States)

Mořkovský, Libor; Janoušek, Václav; Reif, Jiří; Rídl, Jakub; Pačes, Jan; Choleva, Lukáš; Janko, Karel; Nachman, Michael W; Reifová, Radka

2018-02-01

Hybrid sterility is a common first step in the evolution of postzygotic reproductive isolation. According to Haldane's Rule, it affects predominantly the heterogametic sex. While the genetic basis of hybrid male sterility in organisms with heterogametic males has been studied for decades, the genetic basis of hybrid female sterility in organisms with heterogametic females has received much less attention. We investigated the genetic basis of reproductive isolation in two closely related avian species, the common nightingale (Luscinia megarhynchos) and the thrush nightingale (L. luscinia), that hybridize in a secondary contact zone and produce viable hybrid progeny. In accordance with Haldane's Rule, hybrid females are sterile, while hybrid males are fertile, allowing gene flow to occur between the species. Using transcriptomic data from multiple individuals of both nightingale species, we identified genomic islands of high differentiation (F ST ) and of high divergence (D xy ), and we analysed gene content and patterns of molecular evolution within these islands. Interestingly, we found that these islands were enriched for genes related to female meiosis and metabolism. The islands of high differentiation and divergence were also characterized by higher levels of linkage disequilibrium than the rest of the genome in both species indicating that they might be situated in genomic regions of low recombination. This study provides one of the first insights into genetic basis of hybrid female sterility in organisms with heterogametic females. © 2018 John Wiley & Sons Ltd.

Electron field emission characteristics of graphene/carbon nanotubes hybrid field emitter

International Nuclear Information System (INIS)

Chen, Leifeng; He, Hong; Yu, Hua; Cao, Yiqi; Lei, Da; Menggen, QiQiGe; Wu, Chaoxing; Hu, Liqin

2014-01-01

The graphene (GP) and multi-walled carbon nanotubes (MCNTs) hybrid nanostructure emitter was constructed by a larger scale electrophoretic deposition (EPD) method. The field emission (FE) performance of the hybrid emitter is greatly improved compared with that of only GP or MCNTs emitter. The low turn-on electric field (EF), the low threshold EF and the reliability FE properties are obtained from the hybrid emitter. The better FE properties result from the improved electrical properties. For further enhancement FE of hybrids, Ag Nanoparticles (NPs) were decorated on the hybrids and FE characteristics were also studied. These studies indicate that we can use the hybrid nanostructure to improve conductivity and contact resistance, which results in enhancement of the FE properties

A neural network detection system for lower-hybrid cavities in electron plasma density measured by the FREJA satellite

International Nuclear Information System (INIS)

Waldemark, J.; Karlsson, Jan

1995-03-01

This paper presents a lower-hybrid cavity detection system, CDS, for measurements of electron plasma density on the FREJA satellite wave experiment. The system can reduce the amount of data to be analysed by as much as 96% and still retain more than 85% of the desired information. The CDS is a combination of a hybrid neural network, HNN and expert rules. The HNN is a Self Organizing Map, SOM, combined with a feed forward back propagation neural net, BP. The CDS can be controlled by the user to operate with various degrees of sensitivity. Maximum detection capability is as high as 95% with data reduction lowered to 85%. 10 refs

Evidence for the emergence of new rice types of interspecific hybrid origin in West African farmers' fields.

Directory of Open Access Journals (Sweden)

Edwin Nuijten

2009-10-01

Full Text Available In West Africa two rice species (Oryza glaberrima Steud. and Oryza sativa L. co-exist. Although originally it was thought that interspecific hybridization is impossible without biotechnological methods, progenies of hybridization appear to occur in farmer fields. AFLP analysis was used to assess genetic diversity in West Africa (including the countries The Gambia, Senegal, Guinea Bissau, Guinea Conakry, Sierra Leone, Ghana and Togo using 315 rice samples morphologically classified prior to analysis. We show evidence for farmer interspecific hybrids of African and Asian rice, resulting in a group of novel genotypes, and identify possible mechanisms for in-field hybridization. Spontaneous back-crossing events play a crucial role, resulting in different groups of genetic diversity in different regions developed by natural and cultural selection, often under adverse conditions. These new groups of genotypes may have potential relevance for exploitation by plant breeders. Future advances in crop development could be achieved through co-operation between scientists and marginalized farmer groups in order to address challenges of rapid adaptation in a world of increasing socio-political and climatic uncertainty.

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)

Nanostructured hybrid films containing nanophosphor: Fabrication and electronic spectral properties

Energy Technology Data Exchange (ETDEWEB)

Camacho, S.A. [Instituto de Biociencias, Letras e Ciencias Exatas, UNESP - Univ Estadual Paulista, Rua Cristovao Colombo, 2265, 15054-000 Sao Jose do Rio Preto, SP (Brazil); Aoki, P.H.B.; Constantino, C.J.L. [Faculdade de Ciencias e Tecnologia, UNESP - Univ Estadual Paulista, Rua Roberto Simonsen, 305, 19060-900 Presidente Prudente, SP (Brazil); Aroca, R.F. [Materials and Surface Science Group, University of Windsor, Windsor, Ont., Canada N9B3P4 (Canada); Pires, A.M., E-mail: anapires@fct.unesp.br [Faculdade de Ciencias e Tecnologia, UNESP - Univ Estadual Paulista, Rua Roberto Simonsen, 305, 19060-900 Presidente Prudente, SP (Brazil)

2012-11-15

Highlights: Black-Right-Pointing-Pointer Hybrid film containing the cationic polyelectrolyte PAH and Y{sub 2}O{sub 3}: Er, Yb nanophosphor. Black-Right-Pointing-Pointer LbL film growth was monitored by absorbance x concentration in UV-Vis absorption. Black-Right-Pointing-Pointer FTIR indicated existence of secondary interactions between PAH - nanophosphor layers. Black-Right-Pointing-Pointer The morphology and the spatial distribution of the LbL film were analyzed by Raman. Black-Right-Pointing-Pointer We observed intense electronic emission lines from doping ions in the micro-Raman. - Abstract: The intensive research of the optical properties of rare-earth ions is due to the high quantum efficiency of their emission, very narrow bands, and excellent fluorescence monochromaticity. The photoluminescence data presented here show that the nanophosphor remains a green emitter in Layer-by-Layer (LbL) films leading to potential application in optical devices or biological labeling. The LbL technique, an established method for thin film fabrication with molecular architecture control, is used in the manufacture of a hybrid film containing the cationic polyelectrolyte poly (allylamine hydrochloride) (PAH) and Y{sub 2}O{sub 3}: Er, Yb nanophosphor. The spectroscopic properties of this luminescent nanomaterial are extracted from the spectral data of the powder, cast film and LbL films. The growth of the LbL film was monitored by absorbance versus concentration plots in ultraviolet-visible (UV-Vis) absorption spectroscopy. The presence of both PAH and nanophosphor in the LbL film was confirmed by Fourier transform infrared (FTIR) absorption spectroscopy. The FTIR data also ruled out the existence of chemical interactions between the PAH and nanophosphor layers, which means that secondary interactions (like Van der Waals forces) might be the driving forces for LbL film growth. The morphology and the spatial distribution of the LbL film components along the film surface were

Applications of the Hybrid Theory to the Scattering of Electrons from HE+ and Li++ and Resonances in these Systems

Science.gov (United States)

Bhatia, Anand K.

2008-01-01

Applications of the hybrid theory to the scattering of electrons from Ile+ and Li++ and resonances in these systems, A. K. Bhatia, NASA/Goddard Space Flight Center- The Hybrid theory of electron-hydrogen elastic scattering [I] is applied to the S-wave scattering of electrons from He+ and Li++. In this method, both short-range and long-range correlations are included in the Schrodinger equation at the same time. Phase shifts obtained in this calculation have rigorous lower bounds to the exact phase shifts and they are compared with those obtained using the Feshbach projection operator formalism [2], the close-coupling approach [3], and Harris-Nesbet method [4]. The agreement among all the calculations is very good. These systems have doubly-excited or Feshbach resonances embedded in the continuum. The resonance parameters for the lowest ' S resonances in He and Li+ are calculated and they are compared with the results obtained using the Feshbach projection operator formalism [5,6]. It is concluded that accurate resonance parameters can be obtained by the present method, which has the advantage of including corrections due to neighboring resonances and the continuum in which these resonances are embedded.

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

UCare navigator: A dynamic guide to the hybrid electronic and paper medical record in transition.

Science.gov (United States)

Bokser, Seth J; Cucina, Russell J; Love, Jeffrey S; Blum, Michael S

2007-10-11

During the phased transition from a paper-based record to an electronic health record (EHR), we found that clinicians had difficulty remembering where to find important clinical documents. We describe our experience with the design and use of a web-based map of the hybrid medical record. With between 50 to 75 unique visits per day, the UCare Navigator has served as an important aid to clinicians practicing in the transitional environment of a large EHR implementation.

Optical orientation in ferromagnet/semiconductor hybrids

International Nuclear Information System (INIS)

Korenev, V L

2008-01-01

The physics of optical pumping of semiconductor electrons in ferromagnet/semiconductor hybrids is discussed. Optically oriented semiconductor electrons detect the magnetic state of a ferromagnetic film. In turn, the ferromagnetism of the hybrid can be controlled optically with the help of a semiconductor. Spin–spin interactions near the ferromagnet/semiconductor interface play a crucial role in the optical readout and the manipulation of ferromagnetism

Optical orientation in ferromagnet/semiconductor hybrids

Science.gov (United States)

Korenev, V. L.

2008-11-01

The physics of optical pumping of semiconductor electrons in ferromagnet/semiconductor hybrids is discussed. Optically oriented semiconductor electrons detect the magnetic state of a ferromagnetic film. In turn, the ferromagnetism of the hybrid can be controlled optically with the help of a semiconductor. Spin-spin interactions near the ferromagnet/semiconductor interface play a crucial role in the optical readout and the manipulation of ferromagnetism.

Optical Orientation in Ferromagnet/Semiconductor Hybrids

OpenAIRE

Korenev, V. L.

2008-01-01

The physics of optical pumping of semiconductor electrons in the ferromagnet/semiconductor hybrids is discussed. Optically oriented semiconductor electrons detect the magnetic state of the ferromagnetic film. In turn, the ferromagnetism of the hybrid can be controlled optically with the help of the semiconductor. Spin-spin interactions near the interface ferromagnet/semiconductor play crucial role in the optical readout and the manipulation of ferromagnetism.

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.

Hybrid graphene and graphitic carbon nitride nanocomposite: gap opening, electron-hole puddle, interfacial charge transfer, and enhanced visible light response.

Science.gov (United States)

Du, Aijun; Sanvito, Stefano; Li, Zhen; Wang, Dawei; Jiao, Yan; Liao, Ting; Sun, Qiao; Ng, Yun Hau; Zhu, Zhonghua; Amal, Rose; Smith, Sean C

2012-03-07

Opening up a band gap and finding a suitable substrate material are two big challenges for building graphene-based nanodevices. Using state-of-the-art hybrid density functional theory incorporating long-range dispersion corrections, we investigate the interface between optically active graphitic carbon nitride (g-C(3)N(4)) and electronically active graphene. We find an inhomogeneous planar substrate (g-C(3)N(4)) promotes electron-rich and hole-rich regions, i.e., forming a well-defined electron-hole puddle, on the supported graphene layer. The composite displays significant charge transfer from graphene to the g-C(3)N(4) substrate, which alters the electronic properties of both components. In particular, the strong electronic coupling at the graphene/g-C(3)N(4) interface opens a 70 meV gap in g-C(3)N(4)-supported graphene, a feature that can potentially allow overcoming the graphene's band gap hurdle in constructing field effect transistors. Additionally, the 2-D planar structure of g-C(3)N(4) is free of dangling bonds, providing an ideal substrate for graphene to sit on. Furthermore, when compared to a pure g-C(3)N(4) monolayer, the hybrid graphene/g-C(3)N(4) complex displays an enhanced optical absorption in the visible region, a promising feature for novel photovoltaic and photocatalytic applications. © 2012 American Chemical Society

FY1995 study of electronic coservice project which used Optical-Smart Hybrid Card; 1995 nendo hikari IC hybrid card wo mochiite katei kara ukeru gyosei denshika service project

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

As one of advanced multi media service, We can think about electoronization-network changing of the public coservice. that the official system provides. It can be expected to improve the life environment for a nation by the electronization. The purpose of this research is to clarify the off-line administration of an individual information and the issue on security. We constructed the experimental system using the Internet and Optical-IC hybrid card that an individual information is administrated. The system provides the following services. (1) On-stop moving service (2) Electronic certificate publishing service (3) Electronic ticket publishing service We have mounted client terminals at Fuchu city hall, Yokohama city hall, and Keio University, and made field experimentation. (NEDO)

Hydrogen atom as a quantum-classical hybrid system

International Nuclear Information System (INIS)

Zhan, Fei; Wu, Biao

2013-01-01

Hydrogen atom is studied as a quantum-classical hybrid system, where the proton is treated as a classical object while the electron is regarded as a quantum object. We use a well known mean-field approach to describe this hybrid hydrogen atom; the resulting dynamics for the electron and the proton is compared to their full quantum dynamics. The electron dynamics in the hybrid description is found to be only marginally different from its full quantum counterpart. The situation is very different for the proton: in the hybrid description, the proton behaves like a free particle; in the fully quantum description, the wave packet center of the proton orbits around the center of mass. Furthermore, we find that the failure to describe the proton dynamics properly can be regarded as a manifestation of the fact that there is no conservation of momentum in the mean-field hybrid approach. We expect that such a failure is a common feature for all existing approaches for quantum-classical hybrid systems of Born-Oppenheimer type.

GENETIC DIVERSITY OF INTERSPECIFIC HYBRIDS OF THE GENUS ALLIUM L.

Directory of Open Access Journals (Sweden)

V. S. Romanov

2018-01-01

Full Text Available Selection based on interspecific hybridization of fundamentally new plant forms with a unique combination of genetic material allows expanding the scope of genotypic and phenotypic variability. In this work the comparative analysis of plants of interspecific hybrids of genus Allium L. from various inbred descendants of combinations of crossing of species A. cepa х A. vavilovii and A. cepa х A. fistulosum on selection traits is carried out.Forms were identified: by mass of the bulb more than 100 g; with contrasting coloration of dry cover scales bulbs; by the index of the shape of the bulb; on the resistance to peronosporosis of plants of the first year of vegetation and seed plants; by the number of arrows; height of the arrow; on seed production with a sufficiently high percentage of fertile plants. Plants of interspecific hybrids of onions formed bulbs weighing from 20 to 120 g, with white, golden-yellow, dark golden-yellow, brownish and dark purple color of dry covering scales of a bulb. Plants of interspecific hybrids of onions were flat and round-flat shape of the bulb with the frequency of symptoms ranging from 6.9 to 93.3% and from 11.7 to 93.3%. In a phytopathological evaluation of interspecific hybrids of onions the first year of vegetation identified plants with resistance to downy mildew is from 0 to 4.0 points. Was studied the frequency of occurrence of plants in the progenies weight, colour, bulb type, number, height of the seedstalk, seed productivity and resistance to downy mildew. The increase of genetic diversity in onion plants obtained on the basis of interspecific hybridization, backcrossing and inbreeding is shown.

Nanotubule and Tour Molecule Based Molecular Electronics: Suggestion for a Hybrid Approach

Science.gov (United States)

Srivastava, Deepak; Saini, Subhash (Technical Monitor)

1998-01-01

Recent experimental and theoretical attempts and results indicate two distinct broad pathways towards future molecular electronic devices and architectures. The first is the approach via Tour type ladder molecules and their junctions which can be fabricated with solution phase chemical approaches. Second are fullerenes or nanotubules and their junctions which may have better conductance, switching and amplifying characteristics but can not be made through well controlled and defined chemical means. A hybrid approach combining the two pathways to take advantage of the characteristics of both is suggested. Dimension and scale of such devices would be somewhere in between isolated molecule and nanotubule based devices but it maybe possible to use self-assembly towards larger functional and logicalunits.

Highly segmented large-area hybrid photodiodes with bialkali photocathodes and enclosed VLSI readout electronics

CERN Document Server

Braem, André; Filthaut, Frank; Go, A; Joram, C; Weilhammer, Peter; Wicht, P; Dulinski, W; Séguinot, Jacques; Wenzel, H; Ypsilantis, Thomas

2000-01-01

We report on the principles, design, fabrication, and operation of a highly segmented, large-area hybrid photodiode, which is being developed in the framework of the LHCb RICH project. The device consists of a cylindrical, 127 mm diameter vacuum envelope capped with a spherical borosilicate UV-glass entrance window, with an active-to-total-area fraction of 81A fountain-focusing electron optics is used to demagnify the image onto a 50 mm diameter silicon sensor, containing 2048 pads of size 1*1 mm/sup 2/. (10 refs).

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

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

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

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

Lower hybrid waves at the shock front: a reassessment

Directory of Open Access Journals (Sweden)

S. N. Walker

2008-03-01

Full Text Available The primary process occurring at a collisionless shock is the redistribution of the bulk upstream energy into other degrees of freedom. One part of this process results in the acceleration of electrons at the shock front. Accelerated electrons are observed at the terrestrial and other planetary shocks, comets, and their effects are observed in astrophysical phenomena such as supernova remnants and jets in the form of X-ray bremsstrahlung radiation. One of the physical models for electron acceleration at supercritical shocks is based on low-hybrid turbulence due to the presence of reflected ions in the foot region. Since lower hybrid waves propagate almost perpendicular to the magnetic field they can be simultaneously in resonance with both the unmagnetised ions (ω=Vik⊥ and magnetised electrons (ω=Vek||. In this paper, Cluster observations of the electric field are used to study the occurrence of lower hybrid waves in the front of the terrestrial bow shock. It is shown that the lower hybrid waves exist as isolated wave packets. However, the very low level of the observed lower hybrid turbulence is too small to impart significant energisation to the electron population.

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

Maize x Teosinte Hybrid Cobs Do Not Prevent Crop Gene Introgression.

Science.gov (United States)

Chavez, Nancy B; Flores, Jose J; Martin, Joseph; Ellstrand, Norman C; Guadagnuolo, Roberto; Heredia, Sylvia; Welles, Shana R

2012-06-01

Maize x Teosinte Hybrid Cobs Do Not Prevent Crop Gene Introgression. Whether introgression from crops to wild relatives can occur is an important component of transgene risk assessment. In the case of maize, which co-occurs with its wild relative teosinte in Mexico, the possibility of introgression has been controversial. Maize is cross-compatible with teosinte, and spontaneous hybridization is known to occur. Some scientists have hypothesized that the maize x teosinte cob infructescence will prevent progeny dispersal, thus preventing introgression. Motivated by a prior study where we found maize x teosinte hybrid fruits naturally dispersed under field conditions, we tested whether hybrid cobs hold their fruits as tightly as maize cobs. We found the force required to detach hybrid fruits was substantially and significantly less than that for maize. Consequently, we expect that introgression of transgenes from maize into teosinte in Mexico should occur largely unimpeded by the hybrid cob.La mazorca o elote híbrido de maíz x teocintle no impide la introgresión de genes transgénicos provenientes del cultivo. La introgresión entre el maíz cultivado y el maíz silvestre, o teocintle, es un componente importante en la evaluación ambiental relacionada con los riesgos de la introducción de genes transgénicos. La posibilidad de introgresión entre el maíz domesticado y el teocintle ha sido un tema controversial, en particular en México, donde maíz y teocintle coexisten. El maíz es compatible con el teocintle y la hibridización espontánea ocurre entre ellos. Algunos científicos han planteado como hipótesis que al cruzar el maíz con teocintle, la estructura interna de la infrutescencia que sujeta los frutos conocida como la mazorca de maíz o el elote, impide la dispersión de la progenie evitando que la introgresión ocurra. Los resultados de un estudio previo evidencian la dispersión de los frutos híbridos del maíz x teocintle en condiciones naturales

Room Temperature, Hybrid Sodium-Based Flow Batteries with Multi-Electron Transfer Redox Reactions

Science.gov (United States)

Shamie, Jack S.; Liu, Caihong; Shaw, Leon L.; Sprenkle, Vincent L.

2015-01-01

We introduce a new concept of hybrid Na-based flow batteries (HNFBs) with a molten Na alloy anode in conjunction with a flowing catholyte separated by a solid Na-ion exchange membrane for grid-scale energy storage. Such HNFBs can operate at ambient temperature, allow catholytes to have multiple electron transfer redox reactions per active ion, offer wide selection of catholyte chemistries with multiple active ions to couple with the highly negative Na alloy anode, and enable the use of both aqueous and non-aqueous catholytes. Further, the molten Na alloy anode permits the decoupled design of power and energy since a large volume of the molten Na alloy can be used with a limited ion-exchange membrane size. In this proof-of-concept study, the feasibility of multi-electron transfer redox reactions per active ion and multiple active ions for catholytes has been demonstrated. The critical barriers to mature this new HNFBs have also been explored. PMID:26063629

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.).

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.)

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.

Tuning the hybridization and magnetic ground state of electron and hole doped CeOs2Al10 : An x-ray spectroscopy study

Science.gov (United States)

Chen, Kai; Sundermann, Martin; Strigari, Fabio; Kawabata, Jo; Takabatake, Toshiro; Tanaka, Arata; Bencok, Peter; Choueikani, Fadi; Severing, Andrea

2018-04-01

Here we present linear and circular polarized soft x-ray absorption spectroscopy (XAS) data at the Ce M4 ,5 edges of the electron (Ir) and hole-doped (Re) Kondo semiconductor CeOs2Al10 . Both substitutions have a strong impact on the unusual high Néel temperature TN=28.5 K, and also the direction of the ordered moment in case of Ir. The substitution dependence of the linear dichroism is weak thus validating the crystal-field description of CeOs2Al10 being representative for the Re and Ir substituted compounds. The impact of electron and hole doping on the hybridization between conduction and 4 f electrons is related to the amount of f0 in the ground state and reduction of x-ray magnetic circular dichroism. A relationship of c f -hybridization strength and enhanced TN is discussed. The direction and doping dependence of the circular dichroism strongly supports the idea of strong Kondo screening along the crystallographic a direction.

Design and realization of a fast low noise electronics for a hybrid pixel X-ray detector dedicated to small animal imaging

International Nuclear Information System (INIS)

Chantepie, B.

2008-12-01

Since the invention of computerized tomography (CT), charge integration detector were widely employed for X-ray biomedical imaging applications. Nevertheless, other options exist. A new technology of direct detection using semiconductors has been developed for high energy physics instrumentation. This new technology, called hybrid pixel detector, works in photon counting mode and allows for selecting the minimum energy of the counted photons. The ImXgam research team at CPPM develops the PIXSCAN demonstrator, a CT-scanner using the hybrid pixel detector XPAD. The aim of this project is to evaluate the improvement in image quality and in dose delivered during X-ray examinations of a small animal. After a first prototype of a hybrid pixel detector XPAD1 proving the feasibility of the project, a complete imager XPAD2 was designed and integrated in the PIXSCAN demonstrator. Since then, with the evolution of microelectronic industry, important improvements are conceivable. To reducing the size of pixels and to improving the energy resolution of detectors, a third design XPAD3 was conceived and will be soon integrated in a second generation of PIXSCAN demonstrator. In this project, my thesis work consisted in taking part to the design of the detector readout electronics, to the characterization of the chips and of the hybrid pixel detectors, and also to the definition of a auto-zeroing architecture for pixels. The first and second chapters present X-ray medical imaging and particle detection with semi-conductors and its modelling. The third chapter deals with the specifications of electronic circuits for imaging applications first for analog pixels then for digital pixels and describes the general architecture of the integrated circuits. The validation tests are presented in the fourth chapter while the last chapter gives an account of expected changes in pixel electronics

Hybrid circuit prototypes for the CMS Tracker upgrade front-end electronics

International Nuclear Information System (INIS)

Blanchot, G; Honma, A; Kovacs, M; Braga, D; Raymond, M

2013-01-01

New high-density interconnect hybrid circuits are under development for the CMS tracker modules at the HL-LHC. These hybrids will provide module connectivity between flip-chip front-end ASICs, strip sensors and a service board for the data transmission and powering. Rigid organic-based substrate prototypes and also a flexible hybrid design have been built, containing up to eight front-end flip chip ASICs. A description of the function of the hybrid circuit in the tracker, the first prototype designs, results of some electrical and mechanical properties from the prototypes, and examples of the integration of the hybrids into detector modules are presented

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)

Optical emission spectroscopy of metal vapor dominated laser-arc hybrid welding plasma

International Nuclear Information System (INIS)

Ribic, B.; DebRoy, T.; Burgardt, P.

2011-01-01

During laser-arc hybrid welding, plasma properties affect the welding process and the weld quality. However, hybrid welding plasmas have not been systematically studied. Here we examine electron temperatures, species densities, and electrical conductivity for laser, arc, and laser-arc hybrid welding using optical emission spectroscopy. The effects of arc currents and heat source separation distances were examined because these parameters significantly affect weld quality. Time-average plasma electron temperatures, electron and ion densities, electrical conductivity, and arc stability decrease with increasing heat source separation distance during hybrid welding. Heat source separation distance affects these properties more significantly than the arc current within the range of currents considered. Improved arc stability and higher electrical conductivity of the hybrid welding plasma result from increased heat flux, electron temperatures, electron density, and metal vapor concentrations relative to arc or laser welding.

Divergência genética entre progênies de café robusta Genetic divergence among robusta coffe progenies

Directory of Open Access Journals (Sweden)

Milana Gonçalves Ivoglo

2008-12-01

recurrent selection and production of hybrids. The importance of the traits for divergence was, also, evaluated by the sequential discards the variables, according its relative contributions. The trial was carry out in an experimental field located in the Pólo Regional do Nordeste Paulista, Mococa-SP, using randomized blocks with 21 treatments and 24 replicates. The datas were analyzed by Tocher and UPGMA methods. The matrix of genetic divergence was gotten on the generalized Mahalanobis distance that it served of base for the formation of the groups. The employed methods had been efficient in detecting ample genetic variability between the evaluated progenies. Some groups of similarity had been identified. The IAC 2262, IAC 2290, IAC 2286, IAC 2292 and IAC 2291 progenies are indicated to compose programs of intercrosses, being considered the most promising in the attainment of segregantes populations or hybrid heterotics. The characteristics that had less contributed for the genetic divergence had been: canopy diameter before pruning, plant height before pruning and leaf area.

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.

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.

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.

Organic electronic materials: Recent advances in the dft description of the ground and excited states using tuned range-separated hybrid functionals

KAUST Repository

Kö rzdö rfer, Thomas; Bredas, Jean-Luc

2014-01-01

-band-gap polymers.In this Account, we highlight how these failures can be traced back to the delocalization error inherent to semilocal and global hybrid functionals, which leads to the spurious delocalization of electron densities and an overestimation

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)

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.

Hybrid additive manufacturing of 3D electronic systems

International Nuclear Information System (INIS)

Li, J; Wasley, T; Nguyen, T T; Kay, R; Ta, V D; Shephard, J D; Stringer, J; Smith, P; Esenturk, E; Connaughton, C

2016-01-01

A novel hybrid additive manufacturing (AM) technology combining digital light projection (DLP) stereolithography (SL) with 3D micro-dispensing alongside conventional surface mount packaging is presented in this work. This technology overcomes the inherent limitations of individual AM processes and integrates seamlessly with conventional packaging processes to enable the deposition of multiple materials. This facilitates the creation of bespoke end-use products with complex 3D geometry and multi-layer embedded electronic systems. Through a combination of four-point probe measurement and non-contact focus variation microscopy, it was identified that there was no obvious adverse effect of DLP SL embedding process on the electrical conductivity of printed conductors. The resistivity maintained to be less than 4  ×  10 −4 Ω · cm before and after DLP SL embedding when cured at 100 °C for 1 h. The mechanical strength of SL specimens with thick polymerized layers was also identified through tensile testing. It was found that the polymerization thickness should be minimised (less than 2 mm) to maximise the bonding strength. As a demonstrator a polymer pyramid with embedded triple-layer 555 LED blinking circuitry was successfully fabricated to prove the technical viability. (paper)

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.

Lower hybrid waves at the shock front: a reassessment

Directory of Open Access Journals (Sweden)

S. N. Walker

2008-03-01

Full Text Available The primary process occurring at a collisionless shock is the redistribution of the bulk upstream energy into other degrees of freedom. One part of this process results in the acceleration of electrons at the shock front. Accelerated electrons are observed at the terrestrial and other planetary shocks, comets, and their effects are observed in astrophysical phenomena such as supernova remnants and jets in the form of X-ray bremsstrahlung radiation. One of the physical models for electron acceleration at supercritical shocks is based on low-hybrid turbulence due to the presence of reflected ions in the foot region. Since lower hybrid waves propagate almost perpendicular to the magnetic field they can be simultaneously in resonance with both the unmagnetised ions (ω=V_ik_⊥ and magnetised electrons (ω=V_ek_||. In this paper, Cluster observations of the electric field are used to study the occurrence of lower hybrid waves in the front of the terrestrial bow shock. It is shown that the lower hybrid waves exist as isolated wave packets. However, the very low level of the observed lower hybrid turbulence is too small to impart significant energisation to the electron population.

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.

Different selective pressures lead to different genomic outcomes as newly-formed hybrid yeasts evolve

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Piotrowski Jeff S

2012-04-01

Full Text Available Abstract Background Interspecific hybridization occurs in every eukaryotic kingdom. While hybrid progeny are frequently at a selective disadvantage, in some instances their increased genome size and complexity may result in greater stress resistance than their ancestors, which can be adaptively advantageous at the edges of their ancestors' ranges. While this phenomenon has been repeatedly documented in the field, the response of hybrid populations to long-term selection has not often been explored in the lab. To fill this knowledge gap we crossed the two most distantly related members of the Saccharomyces sensu stricto group, S. cerevisiae and S. uvarum, and established a mixed population of homoploid and aneuploid hybrids to study how different types of selection impact hybrid genome structure. Results As temperature was raised incrementally from 31°C to 46.5°C over 500 generations of continuous culture, selection favored loss of the S. uvarum genome, although the kinetics of genome loss differed among independent replicates. Temperature-selected isolates exhibited greater inherent and induced thermal tolerance than parental species and founding hybrids, and also exhibited ethanol resistance. In contrast, as exogenous ethanol was increased from 0% to 14% over 500 generations of continuous culture, selection favored euploid S. cerevisiae x S. uvarum hybrids. Ethanol-selected isolates were more ethanol tolerant than S. uvarum and one of the founding hybrids, but did not exhibit resistance to temperature stress. Relative to parental and founding hybrids, temperature-selected strains showed heritable differences in cell wall structure in the forms of increased resistance to zymolyase digestion and Micafungin, which targets cell wall biosynthesis. Conclusions This is the first study to show experimentally that the genomic fate of newly-formed interspecific hybrids depends on the type of selection they encounter during the course of evolution

ANÁLISIS ESPACIAL DE VARIANZA COMO ALTERNATIVA DE EVALUACIÓN DE ENSAYOS DE PROGENIES FORESTALES

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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.

Generation of viable progeny from dead brooders of endangered catfish Clarias magur (Hamilton, 1822

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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

Experimental demonstration of synergy between electron cyclotron and lower hybrid current drive on Tore Supra

International Nuclear Information System (INIS)

Artaud, J.F.; Giruzzi, G.; Dumont, R.J.; Imbeaux, F.; Bibet, P.; Bouquey, F.; Clary, J.; Ekedahl, A.; Hoang, G.T.; Lennholm, M.; Magne, R.; Segui, J.L.

2004-01-01

Non-inductive current drive (CD) has two main applications in tokamaks: sustainment of a substantial fraction of the toroidal plasma current necessary for the plasma confinement and control of the plasma stability and transport properties by appropriate shaping of the current density profile. For the first kind of applications, lower hybrid (LH) waves are known to provide the highest efficiency (defined as the ratio of the driven current to the injected wave power), although with limited control capability. Conversely, electron cyclotron (EC) waves drive highly localized currents, and are therefore particularly suited for control purposes, but their CD efficiency is much lower than that of LH waves (typically, an order of magnitude in present day experiments). Various calculations have demonstrated an interesting property: the current driven by the simultaneous use of the two waves, I(LH+EC), can be significantly larger than the sum I(LH)+I(EC) of the currents separately driven by the two waves in the same plasma conditions. This property, called synergy effect. The peculiar experimental conditions attainable on the Tore Supra tokamak have allowed the first experimental demonstration of the synergy between EC and LH current drive. The significant improvement of the electron cyclotron current drive (ECCD) efficiency in the presence of low hybrid current drive (LHCD), predicted by kinetic theory and confirmed by stationary experiments on Tore Supra, opens up the possibility of using ECCD as an efficient current profile control tool in LHCD plasmas

Dependence of synergy current driven by lower hybrid wave and electron cyclotron wave on the frequency and parallel refractive index of electron cyclotron wave for Tokamaks

International Nuclear Information System (INIS)

Huang, J.; Chen, S. Y.; Tang, C. J.

2014-01-01

The physical mechanism of the synergy current driven by lower hybrid wave (LHW) and electron cyclotron wave (ECW) in tokamaks is investigated using theoretical analysis and simulation methods in the present paper. Research shows that the synergy relationship between the two waves in velocity space strongly depends on the frequency ω and parallel refractive index N // of ECW. For a given spectrum of LHW, the parameter range of ECW, in which the synergy current exists, can be predicted by theoretical analysis, and these results are consistent with the simulation results. It is shown that the synergy effect is mainly caused by the electrons accelerated by both ECW and LHW, and the acceleration of these electrons requires that there is overlap of the resonance regions of the two waves in velocity space

Electron transport in polycyclic aromatic hydrocarbons/boron nitride hybrid structures: density functional theory combined with the nonequilibrium Green's function.

Science.gov (United States)

Panahi, S F K S; Namiranian, Afshin; Soleimani, Maryam; Jamaati, Maryam

2018-02-07

We investigate the electronic transport properties of two types of junction based on single polyaromatic hydrocarbons (PAHs) and PAHs embedded in boron nitride (h-BN) nanoribbons, using nonequilibrium Green's functions (NEGF) and density functional theory (DFT). In the PAH junctions, a Fano resonance line shape at the Fermi energy in the transport feature can be clearly seen. In hybrid junctions, structural asymmetries enable interactions between the electronic states, leading to observation of interface-based transport. Our findings reveal that the interface of PAH/h-BN strongly affects the transport properties of the structures.

Comparison performance of split plug-in hybrid electric vehicle and hybrid electric vehicle using ADVISOR

Directory of Open Access Journals (Sweden)

Mohd Rashid Muhammad Ikram

2017-01-01

Full Text Available Electric vehicle suffers from relatively short range and long charging times and consequently has not become an acceptable solution to the automotive consumer. The addition of an internal combustion engine to extend the range of the electric vehicle is one method of exploiting the high efficiency and lack of emissions of the electric vehicle while retaining the range and convenient refuelling times of a conventional gasoline powered vehicle. The term that describes this type of vehicle is a hybrid electric vehicle. Many configurations of hybrid electric vehicles have been designed and implemented, namely the series, parallel and power-split configurations. This paper discusses the comparison between Split Plug-in Hybrid Electric Vehicle(SPHEV and Hybrid Electric Vehicle(HEV. Modelling methods such as physics-based Resistive Companion Form technique and Bond Graph method are presented with powertrain component and system modelling examples. The modelling and simulation capability of existing tools such as ADvanced VehIcle SimulatOR (ADVISOR is demonstrated through application examples. Since power electronics is indispensable in hybrid vehicles, the issue of numerical oscillations in dynamic simulations involving power electronics is briefly addressed.

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

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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.

The auroral electron accelerator

International Nuclear Information System (INIS)

Bryant, D.A.; Hall, D.S.

1989-01-01

A model of the auroral electron acceleration process is presented in which the electrons are accelerated resonantly by lower-hybrid waves. The essentially stochastic acceleration process is approximated for the purposes of computation by a deterministic model involving an empirically derived energy transfer function. The empirical function, which is consistent with all that is known of electron energization by lower-hybrid waves, allows many, possibly all, observed features of the electron distribution to be reproduced. It is suggested that the process occurs widely in both space and laboratory plasmas. (author)

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

Cytoplasmic-genetic male sterility gene provides direct evidence for some hybrid rice recently evolving into weedy rice

Science.gov (United States)

Zhang, Jingxu; Lu, Zuomei; Dai, Weimin; Song, Xiaoling; Peng, Yufa; Valverde, Bernal E.; Qiang, Sheng

2015-01-01

Weedy rice infests paddy fields worldwide at an alarmingly increasing rate. There is substantial evidence indicating that many weedy rice forms originated from or are closely related to cultivated rice. There is suspicion that the outbreak of weedy rice in China may be related to widely grown hybrid rice due to its heterosis and the diversity of its progeny, but this notion remains unsupported by direct evidence. We screened weedy rice accessions by both genetic and molecular marker tests for the cytoplasmic male sterility (CMS) genes (Wild abortive, WA, and Boro type, BT) most widely used in the production of indica and japonica three-line hybrid rice as a diagnostic trait of direct parenthood. Sixteen weedy rice accessions of the 358 tested (4.5%) contained the CMS-WA gene; none contained the CMS-BT gene. These 16 accessions represent weedy rices recently evolved from maternal hybrid rice derivatives, given the primarily maternal inheritance of this trait. Our results provide key direct evidence that hybrid rice can be involved in the evolution of some weedy rice accessions, but is not a primary factor in the recent outbreak of weedy rice in China. PMID:26012494

Cytoplasmic-genetic male sterility gene provides direct evidence for some hybrid rice recently evolving into weedy rice.

Science.gov (United States)

Zhang, Jingxu; Lu, Zuomei; Dai, Weimin; Song, Xiaoling; Peng, Yufa; Valverde, Bernal E; Qiang, Sheng

2015-05-27

Weedy rice infests paddy fields worldwide at an alarmingly increasing rate. There is substantial evidence indicating that many weedy rice forms originated from or are closely related to cultivated rice. There is suspicion that the outbreak of weedy rice in China may be related to widely grown hybrid rice due to its heterosis and the diversity of its progeny, but this notion remains unsupported by direct evidence. We screened weedy rice accessions by both genetic and molecular marker tests for the cytoplasmic male sterility (CMS) genes (Wild abortive, WA, and Boro type, BT) most widely used in the production of indica and japonica three-line hybrid rice as a diagnostic trait of direct parenthood. Sixteen weedy rice accessions of the 358 tested (4.5%) contained the CMS-WA gene; none contained the CMS-BT gene. These 16 accessions represent weedy rices recently evolved from maternal hybrid rice derivatives, given the primarily maternal inheritance of this trait. Our results provide key direct evidence that hybrid rice can be involved in the evolution of some weedy rice accessions, but is not a primary factor in the recent outbreak of weedy rice in China.

Wireless, intraoral hybrid electronics for real-time quantification of sodium intake toward hypertension management.

Science.gov (United States)

Lee, Yongkuk; Howe, Connor; Mishra, Saswat; Lee, Dong Sup; Mahmood, Musa; Piper, Matthew; Kim, Youngbin; Tieu, Katie; Byun, Hun-Soo; Coffey, James P; Shayan, Mahdis; Chun, Youngjae; Costanzo, Richard M; Yeo, Woon-Hong

2018-05-22

Recent wearable devices offer portable monitoring of biopotentials, heart rate, or physical activity, allowing for active management of human health and wellness. Such systems can be inserted in the oral cavity for measuring food intake in regard to controlling eating behavior, directly related to diseases such as hypertension, diabetes, and obesity. However, existing devices using plastic circuit boards and rigid sensors are not ideal for oral insertion. A user-comfortable system for the oral cavity requires an ultrathin, low-profile, and soft electronic platform along with miniaturized sensors. Here, we introduce a stretchable hybrid electronic system that has an exceptionally small form factor, enabling a long-range wireless monitoring of sodium intake. Computational study of flexible mechanics and soft materials provides fundamental aspects of key design factors for a tissue-friendly configuration, incorporating a stretchable circuit and sensor. Analytical calculation and experimental study enables reliable wireless circuitry that accommodates dynamic mechanical stress. Systematic in vitro modeling characterizes the functionality of a sodium sensor in the electronics. In vivo demonstration with human subjects captures the device feasibility for real-time quantification of sodium intake, which can be used to manage hypertension.

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

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

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

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

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...

Evolution of insect pest and disease resistant, high-yielding and improved quality varieties of cotton by use of ionizing radiation. Part of a coordinated programme on the use of induced mutations for disease resistance in crop plants

International Nuclear Information System (INIS)

Vasti, S.M.

1981-06-01

Disease resistant, high yielding and higher quality cotton varieties were developed. 42 interspecific hybrid progenies of earlier crosses between Gossypium barbadense and Gossypium tomentosum or Gossypium barbadense and Gossypium hirsutum were included. Out of these, 22 progenies in F 3 generation were irradiated by gamma radiation doses of 20 and 25 kR. A list is given of interspecific hybrid progenies, as are the lists of boll rot susceptible and resistant plants in the irradiated and non-irradiated populations and/or successful crosses made between 1977 and 1978

Island shape, size and interface dependency on electronic and magnetic properties of graphene hexagonal-boron nitride (h-BN) in-plane hybrids

Science.gov (United States)

Akman, Nurten; Özdoğan, Cem

2018-04-01

We systematically investigate the energetics of ion implantation, stability, electronic, and magnetic properties of graphene/hexagonal boron nitrate (h-BN) in-plane hybrids through first principle calculations. We consider hexagonal and triangular islands in supercells of graphene and h-BN layouts. In the case of triangular islands, both phases mix with each other by either solely Csbnd N or Csbnd B bonds. We also patterned triangles with predominating Csbnd N or Csbnd B bonds at their interfaces. The energetics of island implantation is discussed in detail. Formation energies point out that the island implantation could be even exothermic for all hybrids studied in this work. Effects of size and shape of the island, and dominating bonding sort at the island-layout interfaces on the stability, band gap, and magnetic properties of hybrids are studied particularly. The hybrids become more stable with increasing island size. Regardless of the layout, hybrids with hexagonal islands are all non-magnetic and semiconducting. One can thus open a band gap in the semimetallic graphene by mixing it with the h-BN phase. In general, hybrids containing graphene triangles show metallic property and exhibit considerable amount of magnetic moments for possible localized spin utilizations. Total magnetic moment of hybrids with both graphene and h-BN layouts increases with growing triangle island as well. The spin densities of magnetic hybrids are derived from interfaces of the islands and diminish towards their center. We suggest that the increase in stability and magnetic moment depend on the number of atoms at the interfaces rather than the island size.

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

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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.

Molecular Evidence for Natural Hybridization between Cotoneaster dielsianus and C. glaucophyllus

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Mingwan Li

2017-05-01

served as the maternal parent at the initial hybridization event. We proposed that anthropological disturbance provided an opportunity for hybridization between C. dielsianus and C. glaucophyllus, and a tetraploid F1 successfully bred many identical progenies via apomixis. Under this situation, species integrity could be maintained for these Cotoneaster species, but attentions should be kept for this new-born hybrid.

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...

Electron optics in hybrid photodetectors in magnetic fields

International Nuclear Information System (INIS)

Green, D.

1996-12-01

The CMS detector design has the hadronic calorimeter immersed in a 4 T magnetic field. The scintillator photon transducer must work reliably in this environment. The baseline phototransducer is the ''hybrid photomultiplier'', which consists of a standard photocathode (S20) followed by a high field acceleration onto the surface of a Si diode. Such a device has a linear response, 1 e out for every 3.6 eV of potential drop in excess of the threshold needed to penetrate the passivation layer of the diode. A threshold voltage of ∼2 kV is typical of these devices, leading to a gain of ∼2000 at 10 kV applied voltage. In the interest of reducing costs, the Si surface can be cut into pixels. However, the optics of the electron trajectories must be well understood so as to avoid crosstalk between pixels caused by misalignment of the accelerating electric field and the axis of the CMS magnetic field. The depletion depth of the Si is quite standard, ∼300 μm. The source capacity is ∼20 pF. The output pulse has a ∼6 nsec risetime for > 60 V diode biasing. The device is expected to be highly immune to magnetic field effects due to the short spacing, ∼3 mm, between photocathode and Si

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

International Nuclear Information System (INIS)