Utsunomiya University

About: Utsunomiya University is a education organization based out in Utsunomiya, Japan. It is known for research contribution in the topics: Laser & Holography. The organization has 4139 authors who have published 6812 publications receiving 91975 citations. The organization is also known as: Utsunomiya daigaku.

New results on νμ → ντ appearance with the OPERA experiment in the CNGS beam

Abstract: The OPERA neutrino experiment is designed to perform the first observation of neutrino oscillations in direct appearance mode in the ν μ → ν τ channel, via the detection of the τ-leptons created in charged current ν τ interactions. The detector, located in the underground Gran Sasso Laboratory, consists of an emulsion/lead target with an average mass of about 1.2 kt, complemented by electronic detectors. It is exposed to the CERN Neutrinos to Gran Sasso beam, with a baseline of 730 km and a mean energy of 17 GeV. The observation of the first ν τ candidate event and the analysis of the 2008-2009 neutrino sample have been reported in previous publications. This work describes substantial improvements in the analysis and in the evaluation of the detection efficiencies and backgrounds using new simulation tools. The analysis is extended to a sub-sample of 2010 and 2011 data, resulting from an electronic detector-based pre-selection, in which an additional ν τ candidate has been observed. The significance of the two events in terms of a ν μ → ν τ oscillation signal is of 2.40σ.

AtPep3 is a hormone-like peptide that plays a role in the salinity stress tolerance of plants.

Abstract: Significance Hormone-like peptides derived from small coding genes (<100 amino acids) have not been extensively characterized in relation to abiotic stress tolerance. Focusing on 17 salinity stress-inducible small coding genes in Arabidopsis, we showed that four genes conferred increased salinity stress tolerance when overexpressed in transgenic plants. One of the four genes (AtPROPEP3) was found to induce salinity stress tolerance by treatment with a 13-peptide (KPTPSSGKGGKHN) fragment, providing unique functional evidence for enhanced salinity stress tolerance in plants in response to a peptide treatment. Although the 13-peptide fragment shares homology with known peptides associated with immune response, the other peptides may encode unique hormone-like peptides associated with salinity stress tolerance. Peptides encoded by small coding genes play an important role in plant development, acting in a similar manner as phytohormones. Few hormone-like peptides, however, have been shown to play a role in abiotic stress tolerance. In the current study, 17 Arabidopsis genes coding for small peptides were found to be up-regulated in response to salinity stress. To identify peptides leading salinity stress tolerance, we generated transgenic Arabidopsis plants overexpressing these small coding genes and assessed survivability and root growth under salinity stress conditions. Results indicated that 4 of the 17 overexpressed genes increased salinity stress tolerance. Further studies focused on AtPROPEP3, which was the most highly up-regulated gene under salinity stress. Treatment of plants with synthetic peptides encoded by AtPROPEP3 revealed that a C-terminal peptide fragment (AtPep3) inhibited the salt-induced bleaching of chlorophyll in seedlings. Conversely, knockdown AtPROPEP3 transgenic plants exhibited a hypersensitive phenotype under salinity stress, which was complemented by the AtPep3 peptide. This functional AtPep3 peptide region overlaps with an AtPep3 elicitor peptide that is related to the immune response of plants. Functional analyses with a receptor mutant of AtPep3 revealed that AtPep3 was recognized by the PEPR1 receptor and that it functions to increase salinity stress tolerance in plants. Collectively, these data indicate that AtPep3 plays a significant role in both salinity stress tolerance and immune response in Arabidopsis.

Multi-TeV Gamma-Ray Flares from Markarian 421 in 2000 and 2001 Observed with the Tibet Air Shower Array

Abstract: Several strong TeV γ-ray flares were detected from Mrk 421 in the years 2000 and 2001 by the Tibet III air shower array at a level of statistical significance of 5.1 σ. Mrk 421 was unprecedentedly active at X-ray and TeV γ-ray energies during this period, and a positive correlation was found between the change of the all-sky monitor Rossi X-Ray Timing Explorer X-ray flux and the Tibet TeV γ-ray flux. When a power-law energy spectrum for γ-rays from this source is assumed, the spectral index is calculated to be -3.24 ± 0.69 at the most active phase in 2001. The spectral index observed by the Tibet air shower array is consistent with those obtained via imaging air Cerenkov telescopes.

In vitro regeneration of the medicinal woody plant Phellodendron amurense Rupr. through excised leaves

Abstract: Shoot organogenesis and plant establishment has been achieved for Phellodendron amurense Rupr. from excised leaf explants. Young leaf explants were collected from in vitro established shoot cultures and used for the induction of direct shoot regeneration, callus and subsequent differentiation into shoots on MS medium. Direct shoot regeneration was achieved by culturing 1 cm2 sections of about 10-day-old leaves on MS medium enriched with 4.4 μM BAP and 1.0 μM NAA after 4 weeks of culture. The leaf explants produced callus from their cut margins within 3 weeks of incubation on medium supplemented with 2.0 μM TDZ and 4.0 μM 2,4-D or 4.0 μM NAA. The maximum number of adventitious shoots was regenerated from the leaf-derived callus within 4 weeks of culture on MS medium containing 1.5 μM BAP and 1.0 μM NAA. The highest rate of shoot multiplication was achieved at the third subculture, and more than 65 shoots were produced per callus clump. For rooting, the in vitro proliferated and elongated shoots were excised into 2–4 cm long microcuttings, which were planted individually on a root-induction MS medium containing 2.0 μM IBA. Within 3 weeks of transfer to the rooting medium, all the cultured microcuttings produced 2–6 roots. The in vitro regenerated plantlets were transferred to Kanuma soil, and the survival rate ex vitro was 90%.