317 research outputs found
Environmental dependence of polycyclic aromatic hydrocarbon emission at z~0.8. Investigation by observing the RX J0152.7-1357 with AKARI
We study the environmental dependence of the strength of polycyclic aromatic
hydrocarbon (PAH) emission by AKARI observations of RX J0152.7-1357, a galaxy
cluster at z=0.84. PAH emission reflects the physical conditions of galaxies
and dominates 8 um luminosity (L8), which can directly be measured with the L15
band of AKARI. L8 to infrared luminosity (LIR) ratio is used as a tracer of the
PAH strength. Both photometric and spectroscopic redshifts are applied to
identify the cluster members. The L15-band-detected galaxies tend to reside in
the outskirt of the cluster and have optically green colour, R-z'~ 1.2. We find
no clear difference of the L8/LIR behaviour of galaxies in field and cluster
environment. The L8/LIR of cluster galaxies decreases with
specific-star-formation rate divided by that of main-sequence galaxies, and
with LIR, consistent with the results for field galaxies. The relation between
L8/LIR and LIR is between those at z=0 and z=2 in the literature. Our data also
shows that starburst galaxies, which have lower L8/LIR than main-sequence, are
located only in the outskirt of the cluster. All these findings extend previous
studies, indicating that environment affects only the fraction of galaxy types
and does not affect the L8/LIR behaviour of star-forming galaxies.Comment: 8 pages, 7 figures. Accepted for Publication in A&
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Survey of switching techniques in high-speed networks and their performance
One of the most promising approaches for high speed networks for integrated service applications is fast packet switching, or ATM (Asynchronous Transfer Mode). ATM can be characterized by very high speed transmission links and simple, hard wired protocols within a network. To match the transmission speed of the network links, and to minimize the overhead due to the processing of network protocols, the switching of cells is done in hardware switching fabrics in ATM networks.A number of designs has been proposed for implementing ATM switches. While many differences exist among the proposals, the vast majority of them is based on self-routing multi-stage interconnection networks. This is because of the desirable features of multi-stage interconnection networks such as self-routing capability and suitability for VLSI implementation.Existing ATM switch architectures can be classified into two major classes: blocking switches, where blockings of cells may occur within a switch when more than one cell contends for the same internal link, and non-blocking switches, where no internal blocking occurs. A large number of techniques has also been proposed to improve the performance of blocking and nonblocking switches. In this paper, we present an extensive survey of the existing proposals for ATM switch architectures, focusing on their performance issues
An intestinal bacterial metabolite (M1) of ginseng protopanaxadiol saponins inhibits tumor-induced neovascularization
The present study demonstrated that an intestinal bacterial metabolite (M1) of protopanaxadiol-type ginsenosides significantly inhibited the growth of implanted tumor and the intrahepatic metastasis by the implantation of a small fragment of colon 26-L5 tumor into the liver when it was administered orally. These findings indicates that M1 was effective for the inhibition of the growth and metastasis of colon26-L5 cells in addition to lung metastasis of B16-BL6 melanoma cells as have been reported previously. The conditioned medium of colon 26-L5 cellS (CM-L5) induced in vitro tube formation of hepatic sinusoidal endothelial (HSE) cells on Matrigel-coated substrates, which is considered to be an important step in the processes of tumor angiogenesis. \u27This activity of CML5 was abrogated by noncytotoxic concentrations of M1 in a concentration-dependent manner. Similarly, M1 eliminated the ability of CM-L5 to promote the migration of HSE cells concentration-dependently. These findings indicate that M1-induced inhibition of tumor growth and intrahepatic metastasis may be partly related to the suppression of tumor angiogenic responses including capillary tube formation and migration of HSE cells. 本研究では,薬用人参(Panax ginseng C.A.MEYER)のprotopanaxadiol-type ginsenosidesの主要な腸内細菌代謝物M1の経口投与は,マウス結腸癌colon 26-L5細胞の腫瘍小片を肝へ直接移植した後の移植部位での増殖と肝内移転に対して有意に抑制効果を示すことを明らかにした。この結果は,B16-BL6メラノーマ細胞による肺転移を抑制した以前の報告と同様に,co1on 26-L5細胞に対しても有効であることが示された。肝類洞内度細胞(HSE細胞)をマトリゲルをコートした基質上で,colon 26-L5細胞の培養上清(CM-L5)とともに培養すると,腫瘍血管新生の週程における重要なステップのひとつである,内度細胞の菅腔形成を誘導した。CM-L5による菅形成能は,細胞傷害性を示さない濃度範囲のM1により,濃度依存的に抑制された。同様に,CM-L5によるHSE細胞の移動能の亢進を,M1は濃度に依存して抑制した。以上,M1による結腸癌の肝における増殖及び肝内転移の抑制は,内度細胞の骨腔形成及ぴ移動能を含む血管新生反応の抑制と部分的に関係していることが示唆された
Advances and Analysis on Reducing Webpage Response Time with Effect of Edge Computing
Modern webpages consist of many rich objects dynamically produced by servers and client terminals at diverse locations, so we face an increase in web response time. To reduce the time, edge computing, in which dynamic objects are generated and delivered from edge nodes, is effective. For ISPs and CDN providers, it is desirable to estimate the effect of reducing the web response time when introducing edge computing. Therefore, in this paper, we derive a simple formula that estimates the lower bound of the reduction of the response time by modeling flows obtaining objects of webpages. We investigate the effect of edge computing in each webpage category, e.g., News and Sports, using data measured by browsing about 1,000 popular webpages from 12 locations in the world on PlanetLab
Natural history of Upshaw-Schulman syndrome based on ADAMTS13 gene analysis in Japan
Upshaw–Schulman syndrome (USS) is an extremely rare hereditary deficiency of ADAMTS13 activity, termed congenital TTP. The clinical signs are usually mild during childhood, often with isolated thrombocytopenia. But their symptoms become more evident when patients have infections or get pregnant. We identified 43 USS-patients in Japan, who ranged in age from early childhood to 79 years of age. Analysing the natural history of these USS patients based on ADAMTS13 gene mutations may help characterise their clinical phenotypes. Severe neonatal jaundice that requires exchange blood transfusion, a hallmark of USS, was found in 18 of 43 patients (42%). During childhood, 25 of 43 patients were correctly diagnosed with USS without gender disparity. These 25 patients were categorised as having ‘the early-onset phenotype’. Between 15 and 45 years of age, 15 were correctly diagnosed, and, interestingly, they were all female. The remaining three patients were male and were diagnosed when they were older than 45 years of age, suggesting that they were ‘the late-onset phenotype’. Two of these three males developed sudden overt TTP when they were 55 and 63 years old, respectively. These two men had two different homozygous ADAMTS13 gene mutations, p.R193W/p.R193W and p.C1024R/p.C1024R, respectively. Both of which were not discovered in the US or Western countries. In vitro expression studies showed that these two proteins were consistently secreted into the culture medium but to a lesser extent and with reduced activity compared to the wild-type protein. Our results indicate that ‘the late-onset phenotype’ of USS is formed with ethnic specificity.・The definitive version is available at " http://dx.doi.org/10.1111/j.1538-7836.2011.04341.x "・State of the Art 2011 : XXIII Congress of the International Society on Thrombosis and Haemostasis Invited Reviewhttp://dx.doi.org/10.1111/j.1538-7836.2011.04341.
Periodic alternation between intake and exhaust of air in dynamic insulation
Dynamic insulation (DI) can recover heat lost in conduction by drawing cold outdoor air into indoor through an insulation wall in winter. A “breathing DI” system we proposed in the past has functions both as an insulated envelope and as a highly efficient heat exchanger for ventilation. It is alternated periodically that the outdoor air is drawn through half of walls made of breathable inorganic concrete (BIC) and the indoor air is exhausted through the other half of the BIC walls. In order to put the breathing DI system into practice in housing construction, this paper presents some studies from various points of view in addition to the past studies on heat and moisture transport based on laboratory experiments and numerical simulations. We first experimentally studied the filtering efficiency and clogging of a BIC panel. This showed that approximately 30 % of the atmospheric dust can be captured by a BIC panel and no clogging would occur for at least 10 years. We also measured the sorption and desorption of formaldehyde by a BIC panel to confirm the effectiveness of a BIC wall to sorb gaseous state formaldehyde. We furthermore constructed a new test house at Ibaraki, Japan, to confirm the thermal performance of the breathing DI system based on full scale experiments
Performance Analysis of Signaling Delay for Wireless Cellular Networks
In wireless cellular networks, signaling traffic such as location update, paging and handoff due to the user\u27s mobility takes a considerable portion of the total traffic load. In addition, the maximum allowable delays may be different among the signaling packets. In this paper, we present an analytical model for evaluating a total processing delay of signaling packets of wireless cellular networks, which integrates the delays of the radio channel and the processing delay at the wired portion. Through numerical examples, we show that priority processing is effective for reducing the handoff processing delays. We also evaluate the delay difference among cells according to their position within the location area, and the influence of number of terminals upon the processing delays
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