80 research outputs found
Properties of atomic intercalated carbon K4 crystals
The stability of atomic intercalated carbon crystals, XC (X=H,
Li, Be, B, C, N, O, F, Na, Mg, Al, Si, P, S, Cl, K, Ca, Ga, Ge, As, Se, Br, Rb
or Sr) is evaluated by geometry optimization and frozen phonon analysis based
on first principles calculations. Although C is unstable, NaC and
MgC are found to be stable. It is shown that NaC and MgC are
metallic and semi conducting, respectively
A model relating transpiration for Japanese cedar and cypress plantations with stand structure
Previous studies have revealed that changes in forest structure due to management (e.g., thinning, aging, and clearcutting) could affect the forest water balance. However, there are unexplained variability in changes in the annual water balance with changing structure among different sites. This is the case even when analyzing data for specific species/regions. For a more advanced and process-based understanding of changes in the water balance with changing forest structure, we examined transpiration (E) observed using the sap-flux method for 14 Japanese cedar and cypress plantations with various structure (e.g., stem density and diameter) in Japan and surrounding areas and developed a model relating E with structural parameters. We expressed E using the simplified Penman–Monteith equation and modeled canopy conductance (G[c]) as a product of reference G[c] (G[cref]) when vapor pressure deficit is 1.0 kPa and functions expressing the responses of G[c] to meteorological factors. We determined G[cref] and parameters of the functions for the sites separately. E observed for the 14 sites was not reproduced well by the model when using mean values of G[cref] and the parameters among the sites. However, E observed for the sites was reproduced well when using G[cref] determined for each site and mean values of the parameters of the functions among the sites, similar to the case when using G[cref] and the parameters of the functions determined for each site. These results suggest that considering variations in G[cref] among the sites was important to reproduce variations in E, but considering variations in the parameters of the functions was not. Our analysis revealed that G[cref] linearly related with the sapwood area on a stand scale (A) and that Alinearly related with stem density (N) and powers of the mean stem diameter (d[m]). Thus, we proposed a model relating E with A (or N and d[m]), where G[cref] was calculated from A (or N and d[m]) and the parameters of the functions were assumed to be the mean values among the sites. This model estimates changes in Ewith changing structure from commonly available data (N and d[m]), and therefore helps improve our understanding of the underlying processes of the changes in the water balance for Japanese cedar and cypress plantations
Current Performance and On-Going Improvements of the 8.2 m Subaru Telescope
An overview of the current status of the 8.2 m Subaru Telescope constructed
and operated at Mauna Kea, Hawaii, by the National Astronomical Observatory of
Japan is presented. The basic design concept and the verified performance of
the telescope system are described. Also given are the status of the instrument
package offered to the astronomical community, the status of operation, and
some of the future plans. The status of the telescope reported in a number of
SPIE papers as of the summer of 2002 are incorporated with some updates
included as of 2004 February. However, readers are encouraged to check the most
updated status of the telescope through the home page,
http://subarutelescope.org/index.html, and/or the direct contact with the
observatory staff.Comment: 18 pages (17 pages in published version), 29 figures (GIF format),
This is the version before the galley proo
High resolution imaging polarimetry of HL Tau and magnetic field structure
We present high quality near infrared imaging polarimetry of HL Tau at 0.4 to
0.6 arcsec resolution, obtained with Subaru/CIAO and UKIRT/IRCAM. 3-D Monte
Carlo modelling with aligned oblate grains is used to probe the structure of
the circumstellar envelope and the magnetic field, as well as the dust
properties. At J band the source shows a centrosymmetric pattern dominated by
scattered light. In the H and K bands the central source becomes visible and
its polarisation appears to be dominated by dichroic extinction, with a
position angle inclined by ~40 degrees to the disc axis. The polarisation
pattern of the environs on scales up to 200 AU is consistent with the same
dichroic extinction signature superimposed on the centrosymmetric scattering
pattern. These data can be modelled with a magnetic field which is twisted on
scales from tens to hundreds of AU, or alternatively by a field which is
globally misaligned with the disc axis. A unique solution to the field
structure will require spatially resolved circular polarisation data. The best
fit Monte Carlo model indicates a shallow near infrared extinction law. When
combined with the observed high polarisation and non-negligible albedo these
constraints can be fitted with a grain model involving dirty water ice mantles
in which the largest particles have radii slightly in excess of 1 um. The best
fit model has an envelope structure which is slightly flattened on scales up to
several hundred AU. Both lobes of the bipolar outflow cavity contain a
substantial optical depth of dust (not just within the cavity walls). Curved,
approximately parabolic, cavity walls fit the data better than a conical
cavity. The small inner accretion disc observed at millimetre wavelengths is
not seen at this spatial resolution.Comment: Accepted by MNRAS, 21 pages, 10 figure
CO Multi-line Imaging of Nearby Galaxies (COMING) IV. Overview of the Project
Observations of the molecular gas in galaxies are vital to understanding the
evolution and star-forming histories of galaxies. However, galaxies with
molecular gas maps of their whole discs having sufficient resolution to
distinguish galactic structures are severely lacking. Millimeter wavelength
studies at a high angular resolution across multiple lines and transitions are
particularly needed, severely limiting our ability to infer the universal
properties of molecular gas in galaxies. Hence, we conducted a legacy project
with the 45 m telescope of the Nobeyama Radio Observatory, called the CO
Multi-line Imaging of Nearby Galaxies (COMING), which simultaneously observed
147 galaxies with high far-infrared flux in CO, CO, and CO
lines. The total molecular gas mass was derived using the standard
CO-to-H conversion factor and found to be positively correlated with the
total stellar mass derived from the WISE m band data. The fraction of
the total molecular gas mass to the total stellar mass in galaxies does not
depend on their Hubble types nor the existence of a galactic bar, although when
galaxies in individual morphological types are investigated separately, the
fraction seems to decrease with the total stellar mass in early-type galaxies
and vice versa in late-type galaxies. No differences in the distribution of the
total molecular gas mass, stellar mass, and the total molecular gas to stellar
mass ratio was observed between barred and non-barred galaxies, which is likely
the result of our sample selection criteria, in that we prioritized observing
FIR bright (and thus molecular gas-rich) galaxies.Comment: Accepted for publication in PASJ; 47 pages, 5 tables, 29 figures.
On-line supplementary images are available at this URL
(https://astro3.sci.hokudai.ac.jp/~radio/coming/publications/). CO data is
available at the Japanese Virtual Observatory (JVO) website
(https://jvo.nao.ac.jp/portal/nobeyama/coming.do) and the project website
(https://astro3.sci.hokudai.ac.jp/~radio/coming/data/
STUDIES ON CHICK SALMONELLOSIS : II. SALMONELLA SENFTENBERG INFECTION IN CHICKS
Experimental studies were carried out to clarify the mode of S. senftenberg infection in newly hatched chicks in some hatcheries situated in or near Sapporo and to clarify the presence or disappearance of S. senftenberg which invaded into baby chicks' bodies. At the same time the reasons for the appearance of S. senftenberg in hatching compartments of incubators and the influence of S. senftenberg upon baby chicks were discussed. The conclusions obtained are summarized as follows : 1. In any hatchery so far as the writers have investigated, S. senftenberg came to be detected in the hatching compartments of incubators at time over 6〜7 weeks after the beginning of hatching (Tables 1,2 and 3). 2. The newly hatched chicks originated from such incubators are usually infected in the incubators with S. senftenberg through their respiratory and digestive organs, and the rate of S. senftenberg infection among chicks tends to run parallel with the rate of multiplication of S. senftenberg in the incubator (Tables 1,2 and 3). 3. These infected chicks carry the greatest numbers of S. senftenberg during first about 1 week of life, but so far as they are brooded under good feeding, management and sanitation, they remain healthy in appearance. They usually eliminate S. senftenberg from their bodies in 4〜6 weeks without therapeutic measures (Tables 6 and 7) and may be expected to exhibit no sequelae by S. senftenberg in future. 4. The regions where S. senftenberg lurks in baby chicks' bodies are the respiratory and digestive organs (Tables 6 and 7). 5. It is sure that S. senftenberg multiplies in hatching compartments of incubators working with normal temperature and humidity. However it is not yet proved what may bring, and how S. senftenberg is brought into the incubator for the first time. 6. As S. senftenberg contained in incubator is readily killed by formaldehyde gas, the hatching compartments of incubators should be cleansed and disinfected with the fumigation of formalin at intervals of 6 weeks after the beginning of hatching
ISOLATION OF SALMONELLA NEW BRUNSWICK FROM CHICKENS
Salmonella new brunswick was isolated from 4 apparently healthy chicks less than 25 days old. This is considered to be the first instance in which S. new brunswick has been isolated from animals (avian species) other than human beings in Japan
盲腸を利用して虫垂導尿路の延長を図った虫垂臍ストーマMainz pouchの1例
53歳男.8cmの虫垂の遠位側3cmに強い炎症性狭窄が術中に判明した症例で, 盲腸部をGIA自動縫合器を用いて管状化することにより, 虫垂道尿管路の延長(4cmの延長で径9cm)を図った.得られた遊離虫垂をMitrofanoff法でパウチ吻合を行い, 盲腸即断端を臍窩と吻合した.術後経過は順調で, 軽度ストーマ狭窄はあるもののブジーのみで軽快し, 良好な結果が得られたThe Mainz pouch with appendix-umbilical stoma is a very stable method for continent, self-catheterizable urinary reservoir in the presence of a healthy appendix. If the appendix is too short or an unexpected stenosis is seen at its distal portion, the elongation of the conduit using a part of the cecum and the implantation of the conduit to the pouch by the Mitrofanoff method can be a good alternative procedure. We herein report our experience in a 53-year-old male with high grade, invasive bladder tumor, who underwent cystourethrectomy and appendix Mainz pouch operation using the above technique
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