On the Magnetostriction of Iron-Aluminium Alloys and a New Alloy "Alfer"

The magnetostriction of iron-aluminium alloys has been measured by the apparatus designed by the present investigators in various longitudinal fields of less than 1200 Oersteds. The positive magnetostriction of iron gradually increases by the addition of aluminium, while the negative one descreases. All the alloys containing more than 5.90% Al have only a positive magnetostriction, and especially in the case of alloys containing more than 8.80% Al the magnetostriction always increases with the magnetizing field or the intensity of magnetization ; showing no maximum. The magnetostriction at a constant field of 1, 100 Oersteds shows a negative value, in the range of lees than 5.3% Al content, while a positive value in the aluminium content above this percentage. In the range of the aluminium content 11.5-13.2% the magnetostriction is very high ; its highest value being 40×10 of 13.14% Al allcy. These alloys may be excellent magnetostriction materials for a supersonic cscillator and have been called "Alfer" by the present investigators

Evolutionary phases of gas-rich galaxies in a galaxy cluster at z=1.46

We report a survey of molecular gas in galaxies in the XMMXCS J2215.9-1738 cluster at $z=1.46$. We have detected emission lines from 17 galaxies within a radius of $R_{200}$ from the cluster center, in Band 3 data of the Atacama Large Millimeter/submillimeter Array (ALMA) with a coverage of 93 -- 95 GHz in frequency and 2.33 arcmin$^2$ in spatial direction. The lines are all identified as CO $J$=2--1 emission lines from cluster members at $z\sim1.46$ by their redshifts and the colors of their optical and near-infrared (NIR) counterparts. The line luminosities reach down to $L'_{\rm CO(2-1)}=4.5\times10^{9}$ K km s$^{-1}$ pc$^2$. The spatial distribution of galaxies with a detection of CO(2--1) suggests that they disappear from the very center of the cluster. The phase-space diagram showing relative velocity versus cluster-centric distance indicates that the gas-rich galaxies have entered the cluster more recently than the gas-poor star-forming galaxies and passive galaxies located in the virialized region of this cluster. The results imply that the galaxies have experienced ram-pressure stripping and/or strangulation during the course of infall towards the cluster center and then the molecular gas in the galaxies at the cluster center is depleted by star formation.Comment: 7 pages, 4 figures, 1 table, accepted for publication in the ApJ Letter

Superconductivity in a van der Waals layered quasicrystal

van der Waals (vdW) layered transition-metal chalcogenides are attracting significant attention owing to their fascinating physical properties. This group of materials consists of abundant members with various elements, having a variety of different structures. However, all vdW layered materials studied to date have been limited to crystalline materials, and the physical properties of vdW layered quasicrystals have not yet been reported. Here, we report on the discovery of superconductivity in a vdW layered quasicrystal of Ta1.6Te. The electrical resistivity, magnetic susceptibility, and specific heat of the Ta1.6Te quasicrystal fabricated by reaction sintering, unambiguously validated the occurrence of bulk superconductivity at a transition temperature of ~1 K. This discovery can pioneer new research on assessing the physical properties of vdW layered quasicrystals as well as two-dimensional quasicrystals; moreover, it paves the way toward new frontiers of superconductivity in thermodynamically stable quasicrystals, which has been the predominant challenge facing condensed matter physics since the discovery of quasicrystals almost four decades ago

Microscopic Temperature Control Reveals Cooperative Regulation of Actin–Myosin Interaction by Drebrin E

胎児の神経を形作る仕組みは精密な温度センサー --母体の体温維持が神経の成熟に重要であることを示唆--. 京都大学プレスリリース. 2021-11-10.Drebrin E is a regulatory protein of intracellular force produced by actomyosin complexes, that is, myosin molecular motors interacting with actin filaments. The expression level of drebrin E in nerve cells decreases as the animal grows, suggesting its pivotal but unclarified role in neuronal development. Here, by applying the microscopic heat pulse method to actomyosin motility assay, the regulatory mechanism is examined from the room temperature up to 37 °C without a thermal denaturing of proteins. We show that the inhibition of actomyosin motility by drebrin E is eliminated immediately and reversibly during heating and depends on drebrin E concentration. The direct observation of quantum dot-labeled drebrin E implies its stable binding to actin filaments during the heat-induced sliding. Our results suggest that drebrin E allosterically modifies the actin filament structure to regulate cooperatively the actomyosin activity at the maintained in vivo body temperature

Coherent monochromatic phonons in highly purified semiconducting single-wall carbon nanotubes

We have used a femtosecond pump-probe impulsive Raman technique to explore the polarization dependence of coherent optical phonons in highly purified and aligned semiconducting single-wall carbon nanotubes (SWCNTs). Coherent phonon spectra for the radial breathing modes (RBMs) exhibit a different monochromatic frequency between the film and solution samples, indicating the presence of differing exciton excitation processes. By varying the polarization of the incident pump beam on the aligned SWCNT film, we found that the anisotropy of the coherent RBM excitation depends on the laser wavelength, which we consider to be associated with the resonant and off-resonant behavior of RBM excitation

Amino Acid Metabolism and Transport in Soybean Plants

The ammonium produced by nitrogen fixation in the bacteroid is rapidly excreted to cytosol of infected cell of soybean nodules and then assimilated into glutamine and glutamic acid, by glutamine synthetase/glutamate synthase pathway. Most of the nitrogen is further assimilated into ureides, allantoin, and allantoic acid, via purine synthesis, and they are transported through xylem to the shoots. Nitrate absorbed in the roots is reduced by nitrate reductase and nitrite reductase to ammonia either in the roots or leaves. The ammonia is also assimilated by glutamine synthetase/glutamate synthase pathway, and mainly transported by asparagine, and not ureides. The nitrogen transported into leaves is readily utilized for protein synthesis, and then, some of them are decomposed and retransported to roots, apical shoots, and pods via phloem mainly in the form of asparagine