16 research outputs found
A Case of Colonic Metastasis of Breast Cancer Positive for Estrogen Receptor
This is the first report of a metastatic colon cancer of breast cancer positive for estrogen receptor. A 56-year-old woman who had undergone standard radical mastectomy due to right breast cancer was suffered from left lower abdominal pain. Barium enema and proctoscopy revealed a narrowing at the rectum and the descending colon. Needle biopsy of the rectum revealed Group 5. The resection of the left colon, the rectum and the ovaries were performed. Foci were macroscopically present at the rectum, the sigmoid colon and the descending colon. Histological examination revealed that colonic foci were metastases from the breast cancer of lobular carcinoma. The colonic preparation was positive for estrogen receptor
Large-scale Filamentary Structure around the Protocluster at Redshift z=3.1
We report the discovery of a large-scale coherent filamentary structure of
Lyman alpha emitters in a redshift space at z=3.1. We carried out spectroscopic
observations to map the three dimensional structure of the belt-like feature of
the Lyman alpha emitters discovered by our previous narrow-band imaging
observations centered on the protocluster at z=3.1. The feature was found to
consist of at least three physical filaments connecting with each other. The
result is in qualitative agreement with the prediction of the 'biased'
galaxy-formation theories that galaxies preferentially formed in large-scale
filamentary or sheet-like mass overdensities in the early Universe. We also
found that the two known giant Lyman alpha emission-line nebulae showing high
star-formation activities are located near the intersection of these filaments,
which presumably evolves into a massive cluster of galaxies in the local
Universe. This may suggest that massive galaxy formation occurs at the
characteristic place in the surrounding large-scale structure at high redshift.Comment: 11 pages, 3 figures, accepted for publication in ApJ Letter
Gas Motion Study of Lya Emitters at z~2 Using UV and Optical Spectral Lines
We present the results of Magellan/MMIRS and Keck/NIRSPEC spectroscopy for
five Lya emitters (LAEs) at z=2.2 for which high-resolution FUV spectra from
Magellan/MagE are available. We detect nebular emission lines including Ha on
the individual basis and low-ionization interstellar (LIS) absorption lines in
a stacked FUV spectrum, and measure average offset velocities of the Lya line,
Delta_v_Lya, and LIS absorption lines, Delta_v_abs, with respect to the
systemic velocity defined by the nebular lines. For a sample of eight z~2-3
LAEs without AGN from our study and the literature, we obtain Delta_v_Lya =
175+/-35 km s^{-1}, which is significantly smaller than that of Lyman-break
Galaxies (LBGs), Delta_v_Lya=400 km s^{-1}. The stacked FUV spectrum gives
Delta_v_abs = -179 +/- 73 km s^{-1}, comparable to that of LBGs. These positive
Delta_v_Lya and negative Delta_v_abs suggest that LAEs also have outflows. In
contrast to LBGs, however, the LAEs' Delta_v_Lya is as small as |Delta_v_abs|,
suggesting low neutral hydrogen column densities. Such a low column density
with a small number of resonant scattering may cause the observed strong Lya
emission of LAEs. We find an anti-correlation between Lya equivalent width (EW)
and Delta_v_Lya in a compilation of LAE and LBG samples. Although its physical
origin is not clear, this anti-correlation result appears to challenge the
hypothesis that a strong outflow, by means of a reduced number of resonant
scattering, produces a large EW. If LAEs at z>6 have similarly small
Delta_v_Lya values, constraints on the reionization history derived from the
Lya transmissivity may need to be revised.Comment: 15 pages, 13 figures, 7 tables. Accepted for publication in Ap
The End of the Reionization Epoch Probed by Ly-alpha Emitters at z=6.5 in the Subaru Deep Field
We report an extensive search for Lyman-alpha emitters (LAEs) at z=6.5 in the
Subaru Deep Field. Subsequent spectroscopy with Subaru and Keck identified
eight more LAEs, giving a total of 17 spectroscopically confirmed LAEs at
z=6.5. Based on this spectroscopic sample of 17, complemented by a photometric
sample of 58 LAEs, we have derived a more accurate Lyman-alpha luminosity
function of LAEs at z=6.5, which reveals an apparent deficit at the bright end
of ~0.75 mag fainter L*, compared with that observed at z=5.7. The difference
in the LAE luminosity functions between z=5.7 and 6.5 is significant at the
3-sigma level, which is reduced to 2-sigma when cosmic variance is taken into
account. This result may imply that the reionization of the universe has not
been completed at z=6.5. We found that the spatial distribution of LAEs at
z=6.5 was homogeneous over the field. We discuss the implications of these
results for the reionization of the universe.Comment: To appear in APJ vol.648. Only minor corrections have been made.
Black&White version is available at
http://zone.mtk.nao.ac.jp/~kashik/sdf/z6p5lae/paper/sdf_z6p5lae_bw.pd
A Search for Lyman alpha Emitters at Redshift 3.7
We present the results of a survey for emission-line objects based on optical
intermediate-band ( = 5736 \AA ~ and = 280
\AA) and broad-band (, , , and ) observations of the
Subaru/XMM-Newton Deep Field on the 8.2 m Subaru telescope with the Subaru
Prime Focus Camera, Suprime-Cam. All the data were obtained during the
guaranteed time observations of the Suprime-Cam instrument. The
intermediate-band image covered a sky area with 10\minpoint62 \times
12\minpoint40 \approx 132 arcmin in the Subaru/XMM-Newton Deep Field
(Ouchi et al.).
Using this image, we have found 23 emission-line sources whose observed
emission-line equivalent widths are greater than 250 \AA. Their optical
multicolor properties indicate that six emission-line sources are Ly
emitters at 3.7 (). They are either intense
starburst galaxies or active galactic nuclei like quasars at 3.7.
Two more emission-line sources may also be Ly emitters at
3.7 although their multicolor properties are marginal. Among the remaining 15
emission-line objects, eight objects appear strong emission-line galaxies at
lower redshift; e.g., [O {\sc ii}] 3727 emitters at ,
H at , or [O {\sc iii}]5007 emitters at . The remaining seven objects are unclassified because they are
too faint to be detected in broad-band images. We discuss observational
properties of these strong emission-line sources. In particular, our data allow
us to estimate the star formation density at for the first
time.Comment: Accepted for publication in AJ;14 pages, 26 figures (all figures are
JPEG file
Clustering of Lyman Break Galaxies at z=4 and 5 in The Subaru Deep Field: Luminosity Dependence of The Correlation Function Slope
We explored the clustering properties of Lyman Break Galaxies (LBGs) at z=4
and 5 with an angular two-point correlation function on the basis of the very
deep and wide Subaru Deep Field data. We found an apparent dependence of the
correlation function slope on UV luminosity for LBGs at both z=4 and 5. More
luminous LBGs have a steeper correlation function. To compare these
observational results, we constructed numerical mock LBG catalogs based on a
semianalytic model of hierarchical clustering combined with high-resolution
N-body simulation, carefully mimicking the observational selection effects. The
luminosity functions for LBGs predicted by this mock catalog were found to be
almost consistent with the observation. Moreover, the overall correlation
functions of LBGs were reproduced reasonably well. The observed dependence of
the clustering on UV luminosity was not reproduced by the model, unless
subsamples of distinct halo mass were considered. That is, LBGs belonging to
more massive dark haloes had steeper and larger-amplitude correlation
functions. With this model, we found that LBG multiplicity in massive dark
halos amplifies the clustering strength at small scales, which steepens the
slope of the correlation function. The hierarchical clustering model could
therefore be reconciled with the observed luminosity-dependence of the angular
correlation function, if there is a tight correlation between UV luminosity and
halo mass. Our finding that the slope of the correlation function depends on
luminosity could be an indication that massive dark halos hosted multiple
bright LBGs (abridged).Comment: 16 pages, 17 figures, Accepted for publication in ApJ, Full
resolution version is available at
http://zone.mtk.nao.ac.jp/~kashik/sdf/acf/sdf_lbgacf.pd
Completing the Census of Ly-alpha Emitters at the Reionization Epoch
We carried out extended spectroscopic confirmations of Ly-alpha emitters
(LAEs) at z=6.5 and 5.7 in the Subaru Deep Field. Now, the total number of
spectroscopically confirmed LAEs is 45 and 54 at z=6.5 and 5.7, respectively,
and at least 81% (70%) of our photometric candidates at z=6.5 (5.7) have been
spectroscopically identified as real LAEs. We made careful measurements of the
Ly-alpha luminosity, both photometrically and spectroscopically, to accurately
determine the Ly-alpha and rest-UV luminosity functions (LFs). The
substantially improved evaluation of the Ly-alpha LF at z=6.5 shows an apparent
deficit from z=5.7 at least at the bright end, and a possible decline even at
the faint end, though small uncertainties remain. The rest-UV LFs at z=6.5 and
5.7 are in good agreement, at least at the bright end, in clear contrast to the
differences seen in the Ly-alpha LF. These results imply an increase in the
neutral fraction of the intergalactic medium from z=5.7 to 6.5. The rest-frame
equivalent width (EW_0) distribution at z=6.5 seems to be systematically
smaller than z=5.7, and it shows an extended tail toward larger EW_0. The
bright end of the rest-UV LF can be reproduced from the observed Ly-alpha LF
and a reasonable EW_0-UV luminosity relation. Integrating this rest-UV LF
provides the first measurement of the contribution of LAEs to the photon budget
required for reionization. The derived UV LF suggests that the fractional
contribution of LAEs to the photon budget among Lyman break galaxies
significantly increases towards faint magnitudes. Low-luminosity LAEs could
dominate the ionizing photon budget, though this inference depends strongly on
the uncertain faint-end slope of the Ly-alpha LF.Comment: 19 pages, 14 figures. Accepted for publication in Ap
Corrosion Damage Detection in Headrace Tunnel Using YOLOv7 with Continuous Wall Images
Infrastructure that was constructed during the high economic growth period of Japan is starting to deteriorate; thus, there is a need for the maintenance and management of these structures. The basis of maintenance and management is the inspection process, which involves finding and recording damage. However, in headrace tunnels, the water supply is interrupted during inspection; thus, it is desirable to comprehensively photograph and record the tunnel wall and detect damage using the captured images to significantly reduce the water supply interruption time. Given this background, the aim of this study is to establish an investigation and assessment system for deformation points in the inner walls of headrace tunnels and to perform efficient maintenance and management of the tunnels. First, we develop a mobile headrace photography device that photographs the walls of the headrace tunnel with a charge-coupled device line camera. Next, we develop a method using YOLOv7 for detecting chalk marks at the damage locations made during cleaning of the tunnel walls that were photographed by the imaging system, and these results are used as a basis to develop a system that automatically accumulates and plots damage locations and distributions. For chalking detection using continuous wall surface images, a high accuracy of 99.02% is achieved. Furthermore, the system can evaluate the total number and distribution of deteriorated areas, which can be used to identify the causes of change over time and the occurrence of deterioration phenomena. The developed system can significantly reduce the duration and cost of inspections and surveys, and the results can be used to select priority repair areas and to predict deterioration through data accumulation, contributing to appropriate management of headrace tunnels