406 research outputs found
Suzaku Observation of the Diffuse X-Ray Emission from the Open Cluster Westerlund 2: a Hypernova Remnant?
We present the analysis of Suzaku observations of the young open cluster
Westerlund 2, which is filled with diffuse X-ray emission. We found that the
emission consists of three thermal components or two thermal and one
non-thermal components. The upper limit of the energy flux of the non-thermal
component is smaller than that in the TeV band observed with H.E.S.S. This may
indicate that active particle acceleration has stopped in this cluster, and
that the accelerated electrons have already cooled. The gamma-ray emission
observed with H.E.S.S. is likely to come from high-energy protons, which hardly
cool in contrast with electrons. Metal abundances of the diffuse X-ray gas may
indicate the explosion of a massive star in the past.Comment: Accepted for publication in PAS
High Metallicity of the X-Ray Gas up to the Virial Radius of a Binary Cluster of Galaxies: Evidence of Galactic Superwinds at High-Redshift
We present an analysis of a Suzaku observation of the link region between the
galaxy clusters A399 and A401. We obtained the metallicity of the intracluster
medium (ICM) up to the cluster virial radii for the first time. We determine
the metallicity where the virial radii of the two clusters cross each other (~2
Mpc away from their centers) and found that it is comparable to that in their
inner regions (~0.2 Zsun). It is unlikely that the uniformity of metallicity up
to the virial radii is due to mixing caused by a cluster collision. Since the
ram-pressure is too small to strip the interstellar medium of galaxies around
the virial radius of a cluster, the fairly high metallicity that we found there
indicates that the metals in the ICM are not transported from member galaxies
by ram-pressure stripping. Instead, the uniformity suggests that the
proto-cluster region was extensively polluted with metals by extremely powerful
outflows (superwinds) from galaxies before the clusters formed. We also
searched for the oxygen emission from the warm--hot intergalactic medium in
that region and obtained a strict upper limit of the hydrogen density
(nH<4.1x10^-5 cm^-3).Comment: Typo corrected. The published version is available on-line free of
charge by the end of 2008. http://pasj.asj.or.jp/v60/sp1/60s133/60s133.pd
Properties of the Brightest Cluster Galaxy and Its Host Cluster
We investigate the relation between the properties of Brightest Cluster
Galaxies (BCGs) and those of their host clusters. To quantify the properties of
cluster hot gas, we employ the parameter of the fundamental plane of X-ray
clusters. It is found that the offset of the BCG from the peak of cluster X-ray
emission is larger for smaller clusters. The parameter (not the
redshift {\it z}), which mainly depends on virial density ,
is considered to represent the formation epoch of a cluster. We thus consider
that the offset of the BCG is correlated with the dynamical equilibrium state
of its host cluster. On the contrary, no significant correlation is found
between the absolute optical magnitude of the BCG and the parameter . If the
extreme brightness of the BCG is mainly acquired in the course of cluster
evolution by environmental effect, BCGs are expected to be brighter in large
clusters. Our result is not consistent with this simplified view. On the
contrary, it is possible that the extreme brightness of the BCG is likely to be
determined in the early history of cluster collapse.Comment: 18 pages, 9 figures, accepted for publication in Ap
On reproduction of a manuscript "Aquatic Zoology" lectured by Kanzo Uchimura at Suisan Denshujo
内村鑑三講述「水産動物學」は明治二十二年三月から明治二十三年八月まで、水産傳習所の第一回生に対して行われた内村鑑三の講義の筆録である。東京海洋大学附属図書館にその原本が所蔵されている。第一ページに内村鑑三講述と筆録されている。本稿はこの講義筆録を翻刻しその註をつけたものである。Kanzo Uchimura lectured to first year class of Suisan Denshujo (the predecessor of Faculty of Marine Science, Tokyo University of Marine Science and Technology) from March, 1889 to August, 1890, in Meiji era. Original manuscript entitled "Aquatic Zoology" handwritten by a student in the first year class, is deposited in the library of Tokyo University of Marine Science and Technology. In the first page, the title of "Aquatic Zoology lectured by Kanzo Uchimura" is written in kanji by writing brush. The purpose of this paper is to reproduce the manuscript "Aquatic Zoology" and to give some comments.東京海洋大学海洋科学部海洋環境学科魚類学研究
An Efficient Synthesis of 2'-O-(β-D-Ribofuranosyl)biopterin
N(2)-(N,N-Dimethylaminomethylene)-3-[2-(4-nitrophenyl)ethyl]-1',2'-di-O (trimethylsilyl)biopterin (4) was prepared
from biopterin (1a, 86% overall yield) in 5 steps. Glycosylation of 4 with 1,2,3,5-tetra-O-acetyl-β D-ribofuranose (5a) and its 2,3,5-tri-O-benzoyl analog (5b) respectively afforded the corresponding 2'-O-(2,3,5-tri-Oacetyl-
and 2,3,5-tri-O-benzoyl-β-D ribofuranosyl)biopterin derivatives (6a, 42% and 6b, 60%) as major products. Removal of the protecting groups of 6b provided 2'-O-(β-D-ribofuranosyl)biopterin (1c, 87% overall yield) in 3 steps
Two Distinct Pathways to Development of Squamous Cell Carcinoma of the Vulva
Squamous cell carcinoma (SCC) accounts for approximately 95% of the malignant tumors of the vaginal vulva and is mostly found in elderly women. The future numbers of patients with vulvar SCC is expected to rise, mainly because of the proportional increase in the average age of the general population. Two different pathways for vulvar SCC have been put forth. The first pathway is triggered by infection with a high-risk-type Human Papillomavirus (HPV). Integration of the HPV DNA into the host genome leads to the development of a typical vulvar intraepithelial neoplasia (VIN), accompanied with overexpression of p14ARF and p16INK4A. This lesion subsequently forms a warty- or basaloid-type SCC. The HPV vaccine is a promising new tool for prevention of this HPV related SCC of the vulva. The second pathway is HPV-independent. Keratinizing SCC develops within a background of lichen sclerosus (LS) through a differentiated VIN. It has a different set of genetic alterations than those in the first pathway, including p53 mutations, allelic imbalances (AI), and microsatellite instability (MSI). Further clinical and basic research is still required to understand and prevent vulvar SCC. Capsule. Two pathway for pathogenesis of squamous cell carcinoma of the value are reviewed
Study of Genetic Effects of Sulphur Mustard Gas on Former Workers of Ohkunojima Poison Gas Factory and Their Offspring
General health examination and one-dimensional electrophoretic examination to detect mutations at the protein level were conducted in order to elucidate potential genetic effects of sulphur mustard gas on children of the former workers of Ohkunojima Poison Gas Factory.
In the general examination, no disease which was definitely considered to be caused by genetic effects was observed, and no examination values obtained for the children proved to be significantly abnormal compared with those for their parents.
Blood samples from 456 children were electrophoretically examined for 30 protein systems. A total of 36 protein variants were detected in 10 protein systems, and the frequency of variants was 2.63 per 1,000 tests. Family study was completed for 32 of these variants, all of which were confirmed to be genetic variants. In 29,868 locus tests, mutation occurred in germ cells of parents could not be detected.
Among 36 variants, two PGM2 variants and one GPI variant were detected for the first time in this study
Treatment with flunitrazepam of continuous spikes and waves during slow wave sleep (CSWS) in children
SummaryWe describe our treatment of two boys with continuous spikes and waves during slow wave sleep (CSWS). One of the boys was suffering from non-convulsive status epilepticus and the other from conscious disturbance with automatism. Their ictal EEG readings showed continuous diffuse spike and wave complexes, which were considered to show electrical status. The boys were diagnosed as having CSWS, and were later diagnosed with Landau–Kleffner syndrome (LKS). EEG readings returned to normal on intravenous injection of flunitazepam (FZP) at a dose of 0.02mg/kg, suggesting that FZP is an effective treatment for CSWS
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