The first determination of the actinide Th abundance for a red giant of the Ursa Minor dwarf galaxy

The Thorium abundance for the red giant COS82 in the Ursa Minor dwarf spheroidal galaxy is determined based on a high resolution spectrum. This is the first detection of actinides in an extra Galactic object. A detailed abundance pattern is determined for 12 other neutron-capture elements from the atomic number 39 to 68. These elements are significantly over-abundant with respect to other metals like Fe (> 1 dex) and their abundance pattern agrees well with those of the r-process-enhanced, very metal-poor stars known in the Galactic halo, while the metallicity of this object ([Fe/H] ~ -1.5) is much higher than these field stars ([Fe/H] ~ -3.0). The results indicate that the mechanism and the astrophysical site that are responsible for neutron-capture elements in COS82 is similar to that for field r-process-enhanced stars, while the condition of low mass star formation is quite different. An estimate of the age of this object based on the Th abundance ratio is discussed.Comment: 5 pages, 2 figures, 1 table, to appear in PAS

Chemical compositions of six metal-poor stars in the ultra-faint dwarf spheroidal galaxy Bo\"otes I

Ultra-faint dwarf galaxies recently discovered around the Milky Way (MW) contain extremely metal-poor stars, and might represent the building blocks of low-metallicity components of the MW. Among them, the Bo\"otes I dwarf spheroidal galaxy is of particular interest because of its exclusively old stellar population. We determine chemical compositions of six red giant stars in Bo\"otes I, based on the high-resolution spectra obtained with the High Dispersion Spectrograph mounted on the Subaru Telescope. Abundances of 12 elements, including C, Na, alpha, Fe-peak, and neutron capture elements, were determined for the sample stars. The abundance results were compared to those in field MW halo stars previously obtained using an abundance analysis technique similar to the present study. We confirm the low metallicity of Boo-094 ([Fe/H]=-3.4). Except for this star, the abundance ratios ([X/Fe]) of elements lighter than zinc are generally homogeneous with small scatter around the mean values in the metallicities spanned by the other five stars (-2.7-2.7 show no significant enhancement of carbon. The [Mg/Fe] and [Ca/Fe] ratios are almost constant with a modest decreasing trend with increasing [Fe/H] and are slightly lower than the field halo stars. The [Sr/Fe] and [Sr/Ba] ratios also tend to be lower in the Bo\"otes I stars than in the halo stars. Our results of small scatter in the [X/Fe] ratios for elements lighter than zinc suggest that these abundances were homogeneous among the ejecta of prior generation(s) of stars in this galaxy.Comment: 16 pages, 12 figures. Accepted to A&A, language correcte

Buoyancy-driven circulation as horizontal convection on β-plane

The nature of the steady buoyancy-driven circulation is investigated using multi-level numerical models. An ocean which extends over the northern and southern hemispheres is forced by cooling in a confined region and heating in the rest of the ocean through the sea surface. As is already known, the circulation and associated thermal structure strongly depend upon the effect of the vertical diffusivity. This nature of the buoyancy-driven circulation is found in the thermodynamic balance. The vertical diffusion plays an essential role in the whole ocean domain. In counterbalancing the vertical diffusion, the horizontal advection at the deepest levels and the vertical advection in the rest of the interior region plays a dominant role. Thus, horizontal transport of cold water from the convective (cooling) to the diffusive (heating) region occurs mainly in the lowest part of the deep water. It is a natural consequence of predominance of the vertical diffusion that the buoyancy-driven circulation has a significant vertical shear well below the thermocline; the Stommel and Arons pattern for the deep circulation tends to be confined in the lower part of the deep water. Details of a set of alternating zonal jets along the equator and associated meridional circulation are obtained and discussed, and dependence on diffusivity and viscosity is also discussed

Area Modeling using Stay Information for Large-Scale Users and Analysis for Influence of COVID-19

Understanding how people use area in a city can be a valuable information in a wide range of fields, from marketing to urban planning. Area usage is subject to change over time due to various events including seasonal shifts and pandemics. Before the spread of smartphones, this data had been collected through questionnaire survey. However, this is not a sustainable approach in terms of time to results and cost. There are many existing studies on area modeling, which characterize an area with some kind of information, using Point of Interest (POI) or inter-area movement data. However, since POI is data that is statically tied to space, and inter-area movement data ignores the behavior of people within an area, existing methods are not sufficient in terms of capturing area usage changes. In this paper, we propose a novel area modeling method named Area2Vec, inspired by Word2Vec, which models areas based on people's location data. This method is based on the discovery that it is possible to characterize an area based on its usage by using people's stay information in the area. And it is a novel method that can reflect the dynamically changing people's behavior in an area in the modeling results. We validated Area2vec by performing a functional classification of areas in a district of Japan. The results show that Area2Vec can be usable in general area analysis. We also investigated area usage changes due to COVID-19 in two districts in Japan. We could find that COVID-19 made people refrain from unnecessary going out, such as visiting entertainment areas.Comment: This paper is an English translation of the paper published in the Transactions of the Information Processing Society of Japan (http://doi.org/10.20729/00213190

Accessing surface Brillouin zone and band structure of picene single crystals

We have experimentally revealed the band structure and the surface Brillouin zone of insulating picene single crystals (SCs), the mother organic system for a recently discovered aromatic superconductor, with ultraviolet photoelectron spectroscopy (UPS) and low-energy electron diffraction with laser for photoconduction. A hole effective mass of 2.24 m_0 and the hole mobility mu_h >= 9.0 cm^2/Vs (298 K) were deduced in Gamma-Y direction. We have further shown that some picene SCs did not show charging during UPS even without the laser, which indicates that pristine UPS works for high-quality organic SCs.Comment: 5 pages, 4 figures, Phys. Rev. Lett. 108, 226401 (2012

1006-44 A Prognostic Factor in Coronary Artery Disease (CAD): Platelet-Dependent Thrombin Generation in Patients with CAD

We examined platelet-dependent thrombin generation in patients with coronary artery disease (CAD). Thrombin generation was measured according to the method of Aronson et al (Circulation, 1992). 0.5ml of platelet rich plasma (PRP, 15×104/ml) was prepared, and 40mM of CaCl, was added to start clotting. 0.5mM of S-2238 was added to each sample in a microtiter plate every 10min, and the plate was read kinetically at a wavelength of 405nm on a microtiter plate reader. The patients with CAD devided into 3 groups.Thrombin generation 20 min after CaCI2, additon is:Control (n=12)48±10(mOD)Stable angina (SAP) (n=15)79±27Unstable angina (UAP) (n=15)**562±155Acute myocardial infarct (AMI) (n=43)**440±269**p<0.01 compared to SAPThe patients with UAP and AMI showed marked increase in thrombin generation compared to SAP and control subjects. AMI patients with severe coronary artery disease (Group B) showed higher levels of thrombin generation (Group A, Gensini score<32: 382±248 mOD vs Group B, Gensini score> 31: 578±238, P<0.05). LVEF of group A is significantly higher than that of group B (P < 0.05). These findings indicate that patients with UAP and AMI have an evidence of hypercoagulable states and that platelet-dependent thrombin generation may play an important role in pathophysiology of UAP or AMI, and may be a prognostic factor in CAD

Prediction of Electric Field Strength at 10m Distance Using Emission Source Finding Method

The equipment under test (EUT) was modeled by current sources. The current positions were estimated using the finding method of radiated emission source by electric field strength data alone. The current vectors were determined by the conditions, where Norm (deviation between the calculated electric field and the measured one) was minimized. Using estimated current sources model, the electric filed strength at 10m distance was predicted. The predicted results were compared with the measured data for an imitated equipment and a personal computer. The results indicate that the radiation patterns were similar to the measured ones, and the maximum electric field strength at10m distance was comparable to the measured value and the calculated value on the assumption where electric field decreases in proportion to distance.2004 International Symposium on Electromagnetic Compatibility (EMC\u2704/Sendai), June 1-4, 2004, Sendai International Center, Sendai, Japa

石川達三研究 : 新資料の発見による再構築

鹿児島国際大