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.

Study of plasma termination using high-Z noble gas puffing in the JT-60U tokamak

Abstract: Argon, krypton and xenon were puffed with and without simultaneous hydrogen gas puffing into Ohmically heated plasmas of the JT-60U tokamak with low plasma currents in order to study the capability of disruption mitigation. It was found that krypton gas puffing can provide a plasma termination with smaller amounts of runaway electrons in comparison to argon and xenon gas puffing.

OsPIN1b is Involved in Rice Seminal Root Elongation by Regulating Root Apical Meristem Activity in Response to Low Nitrogen and Phosphate

Abstract: The response of plant root development to nutrient deficiencies is critical for crop production. Auxin, nitric oxide (NO), and strigolactones (SLs) are important regulators of root growth under low-nitrogen and -phosphate (LN and LP) conditions. Polar auxin transport in plants, which is mainly dependent on auxin efflux protein PINs, creates local auxin maxima to form the basis for root initiation and elongation; however, the PIN genes that play an important role in LN- and LP-modulated root growth remain unclear. qRT-PCR analysis of OsPIN family genes showed that the expression of OsPIN1b is most abundant in root tip and is significantly downregulated by LN, LP, sodium nitroprusside (SNP, NO donor), and GR24 (analogue of SLs) treatments. Seminal roots in ospin1b mutants were shorter than those of the wild type; and the seminal root, [3H]IAA transport, and IAA concentration responses to LN, LP, SNP, and GR24 application were attenuated in ospin1b-1 mutants. pCYCB1;1::GUS expression was upregulated by LN, LP, SNP, and GR24 treatments in wild type, but not in the ospin1b-1 mutant, suggesting that OsPIN1b is involved in auxin transport and acts as a downstream mediator of NO and SLs to induce meristem activity in root tip in rice under LN and LP.

Origin of protons accelerated by an intense laser and the dependence of their energy on the plasma density

Abstract: We study the high-energy (1-4 MeV) proton production from a slab plasma irradiated by a ultrashort high-power laser. In our 2.5-dimensional particle-in-cell simulations, a p-polarized laser beam of 1.6 x 10(19) W/cm(2), 300 fs, lambda(L)=1.053 microm, illuminates a slab plasma normally; the slab plasma consists of a hydrogen plasma, and the target plasma thickness and the laser spot size are 2.5lambda(L) and 5lambda(L), respectively. The simulation results show that an emitted proton energy depends on the slab plasma density, and three kinds of high-energy proton beams are generated at the target plasma surfaces: one kind of the proton beams is produced at the laser-illuminated target surface and accelerated to the same laser-incident side. The second is generated at the target surface opposite to the laser-illuminated target surface and is accelerated outward on the same side. The third is generated at the laser-illuminated target surface and accelerated to the opposite side while passing through the target plasma. The simulations also show a mechanism of proton accelerations. In an overdense plasma, laser energy goes to energies of hot electrons and magnetic fields in part; the electrons oscillate around the slab plasma so that a static electric field is generated and consequently protons are extracted. The magnetic field generated in the slab plasma exists longer and heats up the plasma electrons to sustain the static electric field even after the laser termination.

Apical dominance in saffron and the involvement of the branching enzymes CCD7 and CCD8 in the control of bud sprouting

Abstract: In saffron (Crocus sativus), new corms develop at the base of every shoot developed from the maternal corm, a globular underground storage stem. Since the degree of bud sprouts influences the number and size of new corms, and strigolactones (SLs) suppress growth of pre-formed axillary bud, it was considered appropriate to investigate SL involvement in physiology and molecular biology in saffron. We focused on two of the genes within the SL pathway, CCD7 and CCD8, encoding carotenoid cleavage enzymes required for the production of SLs. The CsCCD7 and CsCCD8 genes are the first ones isolated and characterized from a non-grass monocotyledonous plant. CsCCD7 and CsCCD8 expression showed some overlapping, although they were not identical. CsCCD8 was highly expressed in quiescent axillary buds and decapitation dramatically reduced its expression levels, suggesting its involvement in the suppression of axillary bud outgrowth. Furthermore, in vitro experiments showed also the involvement of auxin, cytokinin and jasmonic acid on the sprouting of axillary buds from corms in which the apical bud was removed. In addition, CsCCD8 expression, but not CsCCD7, was higher in the newly developed vascular tissue of axillary buds compared to the vascular tissue of the apical bud. We showed that production and transport of auxin in saffron corms could act synergistically with SLs to arrest the outgrowth of the axillary buds, similar to the control of above-ground shoot branching. In addition, jasmonic acid seems to play a prominent role in bud dormancy in saffron. While cytokinins from roots promote bud outgrowth. In addition the expression results of CsCCD8 suggest that SLs could positively regulate procambial activity and the development of new vascular tissues connecting leaves with the mother corm.

Radiolaria: achievements and unresolved issues: taxonomy and cytology

Abstract: The essentials of the taxonomy and cytology of Radiolaria at the order level are summarized from approximately 110 papers. Living Radiolaria comprise representatives of the following orders: Acantharia, Collodaria, Spumellaria, cyrtid Nassellaria, spyrid Nassellaria and Taxopodia ( Sticholonche). This analysis is based on the most recent molecular biological and fossil data. Phaeodaria, which used to belong to the Radiolaria, belong to the Cercozoa now. Heliozoa are closer to the Cercozoa than to the Alveolata or Radiolaria. A molecular phylogenetic analysis indicates that Polycystina (including Collodaria, Spumellaria and Nassellaria) should not be treated as a monophyletic group. “Polycystine” Radiolaria are characterized by the presence of axopodia, a capsular wall, and a fusule. The endoplasm consists of the Golgi bodies, mitochondria, and other organelles, whereas the ectoplasm is an alveolated reticulum with food, digestive, and perialgal vacuoles, suggesting zonal specialization. The Acantharia are characterized by the presence of a periplasmic cortex with myoneme, acting as a motile contractile plasmalemma, rather than a capsular wall. Taxopodia have thick axopodia and a thick nuclear wall instead of a capsular wall. Characteristic protoplasmic structures such as an intracapsular axopodial system and nucleus are found in “polycystine” Radiolaria, but these structures do not seem to reflect phylogenetic relationships.