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We have investigated detailed plasma structure around the recombination front region (RFR), where volume electron-ion recombination (EIR) strongly occurs in detached plasmas, by using two-dimensional (2D) movable probe system as well as laser Thomson scattering diagnostics. The 2D distribution of electron density, electron temperature, and plasma potential around the RFR, has been revealed for the first time. The spatial distribution of the particle loss rate due to EIR estimated from electron temperature and electron density profiles indicated that the three-dimensional structure of the RFR adopts a cone structure. Furthermore, in the peripheral region of the RFR, the radial profile of the electron density was widened locally with increasing cross-field transport caused by plasma fluctuation. From the heat transport analysis of electrons, it was found that the thermal relaxation process between electrons and ions is important for the cooling of electrons, and that the convection of electrons regulates electron heat transport near the RFR. Keywords: Divertor, Detached plasma, Volume recombination, Recombination front

This study proposes a method for evaluating the axial decay length of the plasma pressure in detached helium plasmas with a fixed-point laser Thomson scattering and spectroscopic measurements in the linear divertor plasma simulator NAGDIS-II. By controlling the neutral gas pressure, the highly volume-recombining region called the “recombination front” was moved along the magnetic field. The differential terms for the electron pressure and the recombination-front position with respect to the neutral pressure were obtained. By using these two terms, the decay length of the plasma pressure was qualitatively calculated. In addition, from the movable Langmuir probe measurement, difference between the locally estimated decay length around the recombination front and the decay lengths over a wide axial range was discussed. The proposed method can be applied even in the huge heat flux condition where direct-contact measurements such as the Langmuir probe are not available.

Uridine diphosphate glucose dehydrogenase (UGDH) plays an important role in biosynthesis of hemicellulose by catalyzing oxidation of UDP-glucose (UDP-Glc) to UDP-glucuronate (UDP-GlcA), a key sugar nucleotide involved in biosynthesis of the plant cell wall. In this study, a UGDH ortholog referred to as LgUGDH was isolated from Larix gmelinii using PCR and rapid amplification of cDNA ends techniques. Real-time PCR shows that the LgUGDH gene was expressed primarily in larch stems in addition to its roots and leaves, and Southern blot analysis indicates that UGDH is encoded by two paralogous genes in L. gmelinii. Overexpression of LgUGDH increased the content of soluble sugars and hemicelluloses and enhanced vegetative growth and cold tolerance in transgenic Arabidopsis thaliana. These results reveal that L. gmelinii UGDH participates in sucrose/polysaccharide metabolism and cell wall biosynthesis and may be a good candidate gene for enhancing plant growth, cold tolerance, and hemicellulose content.

Aiming at getting any clue to the mechanism of characteristic behavior of meta-magnetic transition in CeRu2Si2 and the Ce 4f electronic states in Gd-poor contents, the (Ce-Gd)Ru2Si2 crystal mixed system was studied through magnetic measurements. A characteristic behavior of meta-magnetic transition observed in CeRu2Si2 was found to be reproduced in GdRu2Si2 in the temperature range between 30 K and 40 K. The meta-magnetic transition field was increased to higher field by the substitution of small amount of Gd contents of 0.01 and 0.02 at%. Furthermore, the reciprocal susceptibility in CeRu2Si2 (Gd=0) in temperature range between 15 K and 300 K revealed that the electronic state of Ce 4f was dominantly Ce3+, which was in accordance with a previous work, and the electronic states of Ce 4f in CeRu2Si2 could be described by the Van Vleck paramagnetic picture.

Abstract. Objective:  Shikonin, a component of the herbal medicine “Shikon”, is known to suppress inflammatory reactions, but its molecular targets are not identified. This study examines the effect of shikonin on human basophil degranulation response and aims to identify its targets. Materials:  Human basophils in isolated leukocytes from healthy volunteers’ peripheral blood; recombinant human Syk and Lyn tyrosine kinases. Methods:  Histamine release from basophils stimulated with anti-IgE antibody was analyzed fluorimetrically. Syk and Lyn kinase activities were tested in Vitro with recombinant proteins and analyzed by off-chip mobility shift assay. Results:  Shikonin dose-dependently inhibited the histamine release from basophils induced by anti-IgE antibody (IC50 = 2.6 ± 1.0 µM; mean ± SEM). A search for the target(s) of shikonin in the signal cascade of IgE-mediated activation showed that it strongly inhibits Syk (IC50 = 7.8 µM, in the recombinant kinase assay), which plays a pivotal role in the degranulation response. A less significant inhibition was found for Lyn, which phosphorylates FcεRI-βγ subunits and also Syk. Conclusions:  These results indicate that the inhibition of Syk-dependent phosphorylation events might underlie the blocked histamine release from human basophils, thus contributing to the anti-inflammatory effects of shikonin. [ABSTRACT FROM AUTHOR]

Three DNA fragments encoding part of a reverse transcriptase similar to that of Ty1- copia retrotransposons were isolated from suspension-cultured cells of the liverwort Marchantia paleacea var. diptera. Digestion of total DNA with methylation-sensitive and -insensitive isoschizomers revealed that, like those of the subtelomeric region, CpG sequences in retrotransposon genes were hypermethylated. The methylation status and expression of these retrotransposons was less affected by 5-azadeoxycytidine treatment compared to the subtelomeric region, which was considerably demethylated. [ABSTRACT FROM AUTHOR]

Moss chloroplasts should prove useful for studying the cyanobacteria-derived system in chloroplasts. To determine the effects of antibiotics that inhibit bacterial peptidoglycan synthesis, the numbers of chloroplasts in treated Physcomitrella patens cells were counted. Ampicillin and d-cycloserine caused a rapid decrease in the number of chloroplasts per cell. Fosfomycin affected half of the cells, while vancomycin affected a few cells. Conversely, bacitracin had no effect. With the decrease in chloroplast number, macrochloroplasts appeared in antibiotic-treated cells. Removal of the antibiotics resulted in the recovery of chloroplast number, suggesting that the decrease in number was directly dependent on the antibiotic treatment. Microscopic observations showed that the decrease in the number of chloroplasts resulted from cell division without chloroplast division. These results suggest that enzymes derived from the bacterial peptidoglycan synthesis pathway are related to moss chloroplast division. [ABSTRACT FROM AUTHOR]

Abstract This study introduces a novel diagnostic method to assess tropical atmosphere‐ocean coupling, using a two‐dimensional plane defined by the 90‐day high‐pass‐filtered sea surface temperature (SST) and column water vapor (CWV). The method was applied to reanalysis data and high‐resolution coupled atmosphere‐ocean simulation data. In the Indo–Pacific warm pool region, the phase relationship between SST and CWV remained consistent across both reanalysis and simulation data sets. However, differences in the temporal evolution of these variables were observed in the central Pacific region. The heat budget analysis results indicate that the differences between the two data sets in the central Pacific are related to variations in the effects of atmospheric disturbances on SST. This study demonstrates the potential of our novel diagnostic method for evaluating atmosphere–ocean coupling in climate models.