Environmental change based on diatom assemblages from Lake Yamanaka at the northern foot of Mt, Fuji, Central Japan

Environmental history in Lake Yamanaka was investigated based on diatom assemblages obtained from the 17.5m length borehole core in the lake center. Lake Yamanaka (surface area 6.89km²; maximun depth 14.3m; mean depth 9.4m; altitude above sea level 978m) is one of the Fuji Five Lakes and located at the northern foot of Mt.Fuji. Although this lake had been considered formed by the lava flow from Mt.Fuji about 1850 years ago, results of this research suggested that the formation age more old stage on account of the presence of planktonic diatoms mentioned below. The borehole core sample has mainly consists of unconsolidated silts and scoria fall deposits associated with sandstone layers. According to the composition of diatoms contained in silts, the geohistory of this lake was divided into 4 periods;i.e., 1) The 1'st swamp or river period (11.4-9.2m borehole core in depth); Epiphytic or benthic diatomes such as Flagiralia spp. or Epithemia sp. were dominant in these samples. 2) The 1'st lake period(9.2-6.0m borehole core in depth): Planktonic diatoms such as Aulacoseira sp. or Cyclotella sp. were dominant in these samples. 3) The 2'nd swamp or very shallow lake period(6.0-2.5m borehole core in depth): Epiphytic or benthic diatoms became dominant again. 4) The 2'nd lake period (2.5m-surface borehole core): Planktonic diatoms were dominant again.Article信州大学山地水環境教育研究センター研究報告 2: 105-110(2004)departmental bulletin pape

Multipole Fluctuations in Filled Skutterudites

In order to clarify exotic multipole properties of filled skutterudites, we evaluate multipole susceptibility for $n$=1$\sim$5, where $n$ is the local $f$-electron number, on the basis of a multiorbital Anderson model constructed using the $j$-$j$ coupling scheme. For $n$=1, magnetic fluctuations dominate over low-temperature electronic properties, while for $n$=2 and 4, electronic states are dominated by both magnetic and quadrupole fluctuations. For $n$=3 and 5, octupole fluctuations are found to be significant, depending on the crystalline electric field potential. We discuss possible relevance of the results to actual materials.Comment: 4 pages, 3 figures, JPSJ2.cls. To be published in J. Phys. Soc. Jp

Field resilient superconductivity in atomic layer crystalline materials

The recent study [S. Yoshizawa et al., Nature Communications 12, 1 (2021)] reported the field resilient superconductivity, that is, the enhancement of an in-plane critical magnetic field $H^{||}_{\rm c2}$ exceeding the paramagnetic limiting field in an atomic layer crystalline ($\sqrt{7}\times\sqrt{3}$)-In on a Si(111) substrate. The present article elucidates the origin of the observed field resilient noncentrosymmetric superconductivity in the highly crystalline two dimensional material. We developed the quasiclassical theory by incorporating the Fermi surface anisotropy together with an anisotropic spin splitting specific to atomic layer crystalline systems. The enhancement of the rescaled $H^{||}_{\rm c2}$ by the critical temperature at zero field occurs not only due to the disorder effect but also to an anisotropic non-ideal Rashba spin texture depending on the field direction. We also study the parity mixing effect to show the enhancement of $H^{||}_{\rm c2}$ is limited in the moderately clean regime because of the fragile $s$-wave pairing against nonmagnetic scattering in the case of the dominant odd parity component of a pair wavefunction. Furthermore, from the analysis of the transition line, we identify the field resilience factor taking account of the scattering and suppression of paramagnetic effects and discuss the origin of the field resilient superconductivity. Through the fitting of the $H^{||}_{\rm c2}$ data, the normal state electron scattering is discussed, mainly focusing on the role of atomic steps on a Si(111) surface.Comment: 13 pages, 6 figures, 1 tabl

Non-invasive assessment of arterial stiffness using oscillometric blood pressure measurement

<p>Abstract</p> <p>Background</p> <p>Arterial stiffness is a major contributor to cardiovascular diseases. Because current methods of measuring arterial stiffness are technically demanding, the purpose of this study was to develop a simple method of evaluating arterial stiffness using oscillometric blood pressure measurement.</p> <p>Methods</p> <p>Blood pressure was conventionally measured in the left upper arm of 173 individuals using an inflatable cuff. Using the time series of occlusive cuff pressure and the amplitudes of pulse oscillations, we calculated local slopes of the curve between the decreasing cuff pressure and corresponding arterial volume. Whole pressure-volume curve was derived from numerical integration of the local slopes. The curve was fitted using an equation and we identified a numerical coefficient of the equation as an index of arterial stiffness (Arterial Pressure-volume Index, API). We also measured brachial-ankle (baPWV) PWV and carotid-femoral (cfPWV) PWV using a vascular testing device and compared the values with API. Furthermore, we assessed carotid arterial compliance using ultrasound images to compare with API.</p> <p>Results</p> <p>The slope of the calculated pressure-volume curve was steeper for compliant (low baPWV or cfPWV) than stiff (high baPWV or cfPWV) arteries. API was related to baPWV (<it>r </it>= -0.53, <it>P </it>< 0.05), cfPWV (<it>r </it>= -0.49, <it>P </it>< 0.05), and carotid arterial compliance (<it>r </it>= 0.32, <it>P </it>< 0.05). A stepwise multiple regression analysis demonstrated that baPWV and carotid arterial compliance were the independent determinants of API, and that API was the independent determinant of baPWV and carotid arterial compliance.</p> <p>Conclusions</p> <p>These results suggest that our method can simply and simultaneously evaluate arterial stiffness and blood pressure based on oscillometric measurements of blood pressure.</p

An electron-microscopic study on lipogenesis

With the purpose to elucidate morphologically the site where fat synthesis takes place in the cell, electron-microscopic observation has been conducted on the interscapular brown fat tissue of mice at various periods of carbohydrate introduction after starvation. By starving mice, the depot lipids in the brown fat have been discharged almost completely, and the carbohydrate introduction has caused the biosynthesis of lipids from carbohydrtates in the same tissue. Observations on the tissues proved that the lipogenesis in the brown fat tissue cells takes place in the ground substance keeping the intimate correlation with the endoplasmic reticulum but not in the mitochondria.</p

Lokiarchaeota archaeon schizorhodopsin-2 (LaSzR2) is an inward proton pump displaying a characteristic feature of acid-induced spectral blue-shift

The photoreactive protein rhodopsin is widespread in microorganisms and has a variety of photobiological functions. Recently, a novel phylogenetically distinctive group named 'schizorhodopsin (SzR)' has been identified as an inward proton pump. We performed functional and spectroscopic studies on an uncharacterised schizorhodopsin from the phylum Lokiarchaeota archaeon. The protein, LaSzR2, having an all-trans-retinal chromophore, showed inward proton pump activity with an absorption maximum at 549 nm. The pH titration experiments revealed that the protonated Schiff base of the retinal chromophore (Lys188, pK(a)=12.3) is stabilised by the deprotonated counterion (presumably Asp184, pK(a)=3.7). The flash-photolysis experiments revealed the presence of two photointermediates, K and M. A proton was released and uptaken from bulk solution upon the formation and decay of the M intermediate. During the M-decay, the Schiff base was reprotonated by the proton from a proton donating residue (presumably Asp172). These properties were compared with other inward (SzRs and xenorhodopsins, XeRs) and outward proton pumps. Notably, LaSzR2 showed acid-induced spectral 'blue-shift' due to the protonation of the counterion, whereas outward proton pumps showed opposite shifts (red-shifts). Thus, we can distinguish between inward and outward proton pumps by the direction of the acid-induced spectral shift