29 research outputs found

    Neutrino Oscillations, Fluctuations and Solar Magneto-gravity Waves

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    This review has two parts. The first part summarizes the current observational constraints on fluctuations in the solar medium deep within the solar Radiative Zone, and shows how the KamLAND and SNO-salt data combine to make the experimental determination of the neutrino oscillation parameters largely insensitive to prior assumptions about the nature of these oscillations. As part of a search for plausible sources of solar fluctuations to which neutrinos could be sensitive, the second part of the talk summarizes a preliminary analysis of the influence of magnetic fields on helioseismic waves. Using simplifying assumptions which should apply to modes in the solar radiative zone, we find a resonance between Alfven waves and helioseismic g-modes which potentially modifies the solar density profile fairly significantly over comparatively short distance scales, too narrow to be ruled out by present-day analyses of p-wave helioseismic spectra.Comment: Plenary talk presented at AHEP 2003, Valencia, Spain, October 200

    Large mixing angle oscillations as a probe of the deep solar interior

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    We re-examine the sensitivity of solar neutrino oscillations to noise in the solar interior using the best current estimates of neutrino properties. Our results show that the measurement of neutrino properties at KamLAND provides new information about fluctuations in the solar environment on scales to which standard helioseismic constraints are largely insensitive. We also show how the determination of neutrino oscillation parameters from a combined fit of KamLAND and solar data depends strongly on the magnitude of solar density fluctuations. We argue that a resonance between helioseismic and Alfven waves might provide a physical mechanism for generating these fluctuations and, if so, neutrino-oscillation measurements could be used to constrain the size of magnetic fields deep within the solar radiative zone.Comment: 13 pages, LaTeX file using AASLaTeX, 6 figures included. Improved version including the new KamLAND data. To appear in APJ letter

    Resonant origin for density fluctuations deep within the Sun: helioseismology and magneto-gravity waves

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    We analyze helioseismic waves near the solar equator in the presence of magnetic fields deep within the solar radiative zone. We find that reasonable magnetic fields can significantly alter the shapes of the wave profiles for helioseismic g-modes. They can do so because the existence of density gradients allows g-modes to resonantly excite Alfven waves, causing mode energy to be funnelled along magnetic field lines, away from the solar equatorial plane. The resulting wave forms show comparatively sharp spikes in the density profile at radii where these resonances take place. We estimate how big these waves might be in the Sun, and perform a first search for observable consequences. We find the density excursions at the resonances to be too narrow to be ruled out by present-day analyses of p-wave helioseismic spectra, even if their amplitudes were to be larger than a few percent. (In contrast it has been shown in (Burgess et al. 2002) that such density excursions could affect solar neutrino fluxes in an important way.) Because solar p-waves are not strongly influenced by radiative-zone magnetic fields, standard analyses of helioseismic data should not be significantly altered. The influence of the magnetic field on the g-mode frequency spectrum could be used to probe sufficiently large radiative-zone magnetic fields should solar g-modes ever be definitively observed. Our results would have stronger implications if overstable solar g-modes should prove to have very large amplitudes, as has sometimes been argued.Comment: 18 pages, 6 figures; misprints correcte

    БИОЛОГИЧЕСКАЯ ЭФФЕКТИВНОСТЬ РАЗЛИЧНЫХ ПРЕПАРАТОВ ПРОТИВ СЕМЕННОЙ ИНФЕКЦИИ СОСУДИСТОГО БАКТЕРИОЗА КАПУСТЫ

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    Black rot (pathogen – Xanthomonas campestris pv. campestris) is one of the most harmful diseases of brassicas. Seedlings growing in trays in greenhouse can meet rapid spreading of the pathogen and heavy yield loss even at very low seed infection level. This work was targeted on efficiency comparison for different plant protection agents against black root infection in seeds. Antibacterial effect of the agents was tested in vitro by well diffusion, direct placement of the agent onto bacterial lawn, and by incubation of bacterial suspension with the agents. Biological efficiency of the agents against seed infection was tests by seed soaking or by wet treatment. High antibacterial effect against black rot pathogen in vitro was shown for bacteriophage cocktail, Biocomposite-correct, Zeroxxe, Peroxyacetic acid (NUK15), Ps 11, and Kocide 2000. Highest biological efficiency against seed infection by black rot was shown for bacteriophage cocktail, Biocomposite-correct, Zeroxxe, Peroxyacetic acid (NUK15), and Kocide 2000.Сосудистый бактериоз (возбудитель – Xanthomonas campestris pv. campestris) – одна из наиболее опасных болезней капустных культур. При выращивании рассадным методом даже небольшая зараженность семян приводит к массовому распространению патогена и, в дальнейшем, к значительным потерям урожая в поле. Целью работы было сравнительное испытание эффективности препаратов различного происхождения в отношении семенной инфекции сосудистого бактериоза капусты. Проводили оценку антибактериальной активности препаратов in vitro методом диффузии из лунок, методом нанесения капли препарата на газон бактерий, а также методом совместной инкубации суспензий испытываемых препаратов и патогена. Оценку биологическую эффективности препаратов против семенной инфекции сосудистого бактериоза капусты проводили методами замачивания семян и обработки с увлажнением. Показано, что сильной антибактериальной активностью по отношению к возбудителю сосудистого бактериоза капусты в условиях in vitro обладали консорциум бактериофагов, Биокомпозит-коррект, Зерокс, НУК 15, Ps 11 и Косайд 2000. Наибольшую биологическую эффективность в подавлении семенной инфекции сосудистого бактериоза показали бактериофаги, Биокомпозит-коррект, НУК 15, Зерокс и Косайд 2000

    Cornering Solar Radiative-Zone Fluctuations with KamLAND and SNO Salt

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    We update the best constraints on fluctuations in the solar medium deep within the solar Radiative Zone to include the new SNO-salt solar neutrino measurements. We find that these new measurements are now sufficiently precise that neutrino oscillation parameters can be inferred independently of any assumptions about fluctuation properties. Constraints on fluctuations are also improved, with amplitudes of 5% now excluded at the 99% confidence level for correlation lengths in the range of several hundred km. Because they are sensitive to correlation lengths which are so short, these solar neutrino results are complementary to constraints coming from helioseismology.Comment: 4 pages, LaTeX file using RevTEX4, 6 figures include

    THE BIOLOGICAL EFFECTIVENESS OF VARIOUS PREPARATIONS AGAINST SEED INFECTION OF CABBAGE BLACK ROT

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    Black rot (pathogen – Xanthomonas campestris pv. campestris) is one of the most harmful diseases of brassicas. Seedlings growing in trays in greenhouse can meet rapid spreading of the pathogen and heavy yield loss even at very low seed infection level. This work was targeted on efficiency comparison for different plant protection agents against black root infection in seeds. Antibacterial effect of the agents was tested in vitro by well diffusion, direct placement of the agent onto bacterial lawn, and by incubation of bacterial suspension with the agents. Biological efficiency of the agents against seed infection was tests by seed soaking or by wet treatment. High antibacterial effect against black rot pathogen in vitro was shown for bacteriophage cocktail, Biocomposite-correct, Zeroxxe, Peroxyacetic acid (NUK15), Ps 11, and Kocide 2000. Highest biological efficiency against seed infection by black rot was shown for bacteriophage cocktail, Biocomposite-correct, Zeroxxe, Peroxyacetic acid (NUK15), and Kocide 2000

    Evaluation of resistance of head cabbage hybrids to black rot disease

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    The paper presents the results of a comparison of the reaction of commercial hybrids of cabbage infected by different methods and different strains of the black rot pathogen Xanthomonas campestris pv. campestris. The influence of the infection method and strain on progress of pathogen in the plant was evaluated by statistical methods. The qualitative response of hybrids to infection by a number of the pathogen strains of different races was used to build a validated model of gene-for- gene interaction. It is shown that due to change of genetic structure of the pathogen in 2012, were previously resistant hybrids became susceptible to a new population of the pathogen
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