Recent progress in silica aerogel Cherenkov radiator

In this paper, we present recent progress in the development of hydrophobic silica aerogel as a Cherenkov radiator. In addition to the conventional method, the recently developed pin-drying method for producing high-refractive-index aerogels with high transparency was studied in detail. Optical qualities and large tile handling for crack-free aerogels were investigated. Sufficient photons were detected from high-performance aerogels in a beam test.Comment: Proceedings of 2nd International Conference on Technology and Instrumentation in Particle Physics (TIPP 2011), to be published in Physics Procedia, 8 pages, 7 figure

Super Yang-Mills Theory from a Supermatrix Model

It is known that Yang-Mills theories on non-commutative space can be derived from large-N reduced models. Gauge fields in non-commutative Yang-Mills theories can be described as fluctuations of matrices expanded about an appropriate classical solution of the reduced models. We investigate a generalization of this procedure in superfield formalism. We show that we can construct a supermatrix model such that D=4 $\N=1$ super Yang-Mills theory can be derived from it. In addition, we can couple matter supermatrices to this supermatrix model and also construct models corresponding to $\N=2$ and $\N=4$ super Yang-Mills theories. In these investigations, we need to introduce a new non-anti-commutative superspace, and we investigate the definition of field theories on this space.Comment: 24 pages, published versio

Direct derivation of the Veneziano-Yankielowicz superpotential from matrix model

We derive the Veneziano-Yankielowicz superpotential directly from the matrix model by fixing the measure precisely. The essential requirement here is that the effective superpotential of the matrix model corresponding to the ${\cal N}=4$ supersymmetric Yang-Mills theory vanishes except for the tree gauge kinetic term. Thus we clarify the reason why the matrix model reproduces the Veneziano-Yankielowicz superpotential correctly in the Dijkgraaf-Vafa theory.Comment: 13 pages, to appear in Phys. Lett.

Dijkgraaf-Vafa theory as large-N reduction

We construct a large-N twisted reduced model of the four-dimensional super Yang-Mills theory coupled to one adjoint matter. We first consider a non-commutative version of the four-dimensional superspace, and then give the mapping rule between matrices and functions on this space explicitly. The supersymmetry is realized as a part of the internal $U(\infty)$ gauge symmetry in this reduced model. Our reduced model can be compared with the Dijkgraaf-Vafa theory that claims the low-energy glueball superpotential of the original gauge theory is governed by a simple one-matrix model. We show that their claim can be regarded as the large-N reduction in the sense that the one-matrix model they proposed can be identified with our reduced model. The map between matrices and functions enables us to make direct identities between the free energies and correlators of the gauge theory and the matrix model. As a by-product, we can give a natural explanation for the unconventional treatment of the one-matrix model in the Dijkgraaf-Vafa theory where eigenvalues lie around the top of the potential.Comment: 34 pages, LaTeX, to appear in Nucl. Phys.

Selective cyclooxygenase-2 inhibitors show a differential ability to inhibit proliferation and induce apoptosis of colon adenocarcinoma cells

AbstractAlthough the influence of selective cyclooxygenase (COX)-2 inhibitors on the proliferation of colon adenocarcinoma cells have been the subject of much investigation, relatively little research has compared the effects of different COX-2 inhibitors. Celecoxib strongly suppressed the proliferation of COX-2 expressing HT-29 cells at 10–40 μM. NS-398 and nimesulide also inhibited cell proliferation, whereas rofecoxib, meloxicam, and etodolac did not. Only celecoxib induced apoptosis of HT-29 cells, as detected on the basis of DNA fragmentation, TUNEL positivity, and caspase-3/7 activation. DNA fragmentation was also increasd in COX-2 non-expressing cell lines (SW-480 and HCT-116) by exposure to celecoxib for 6–24 h. All six COX-2 inhibitors suppressed the production of prostaglandin E2 by HT-29 cells, suggesting that the pro-apoptotic effect of celecoxib was unrelated to inhibition of COX-2. Inactivation of Akt might explain the differential pro-apoptotic effect of these selective COX-2 inhibitors on colon adenocarcinoma cells

A New Minimally Invasive Technique of Combined Chest Wall Resection for Lung Cancer : Advanced Data of Implication of Advanced Bipolar Device in Video-Assisted Chest Wall Resection for Lung Cancer.

We describe a novel method for resecting lung cancer that has invaded the chest wall using an advanced bipolar device during video-assisted thoracoscopic surgery. The method is convenient for both tumor and chest wall resection because it is easy to handle and less invasive than the currently used technique

Congenital Cystic Disease of the lung : An Autopsy Case

Many varieties of cysts occur in the lung : it includes not only true cysts but all lesions which mimic them. Recently congenital cystic disease of the lung has become widely observed and reported in literature. This is an autopsy case of congenital cystic disease of the lung of a new born

Optical and radiographical characterization of silica aerogel for Cherenkov radiator

We present optical and X-ray radiographical characterization of silica aerogels with refractive index from 1.05 to 1.07 for a Cherenkov radiator. A novel pin-drying method enables us to produce highly transparent hydrophobic aerogels with high refractive index by shrinking wet-gels. In order to investigate the uniformity in the density (i.e., refractive index) of an individual aerogel monolith, we use the laser Fraunhofer method, an X-ray absorption technique, and Cherenkov imaging by a ring imaging Cherenkov detector in a beam test. We observed an increase in density at the edge of the aerogel tiles, produced by pin-drying.Comment: To be published in IEEE Trans. Nucl. Sci., 7 pages, 9 figures, 1 tabl

The Arginine Residue within the C-Terminal Active Core of Bombyx mori Pheromone Biosynthesis-Activating Neuropeptide is Essential for Receptor Binding and Activation

In most lepidopteran insects, the biosynthesis of sex pheromones is regulated by pheromone biosynthesis-activating neuropeptide (PBAN). Bombyx mori PBAN (BomPBAN) consists of 33 amino acid residues and contains a C-terminus FSPRLamide motif as the active core. Among neuropeptides containing the FXPRLamide motif, the arginine (Arg, R) residue at the second position from the C-terminus is highly conserved across several neuropeptides, which can be designated as RXamide peptides. The purpose of this study was to clarify the role of the Arg residue in the BomPBAN active core. We synthesized 10-residue peptides corresponding to the C-terminal part of BomPBAN with a series of replacements at the second position from the C-terminus, termed the C2 position, and measured their efficacy in stimulating Ca2+ influx in insect cells expressing a fluorescent PBAN receptor chimera (PBANR–EGFP) using the fluorescent Ca2+ indicator, Fura Red–AM. The PBAN analogs with the C2 position replaced with alanine (Ala, A), aspartic acid (Asp, D), serine (Ser, S), or l-2-aminooctanoic acid (Aoc) decreased PBAN-like activity. RC2A (SKTRYFSPALamide) and RC2D (SKTRYFSPDLamide) had the lowest activity and could not inhibit the activity of PBAN C10 (SKTRYFSPRLamide). We also prepared Rhodamine Red-labeled peptides of the PBAN analogs and examined their ability to bind PBANR. In contrast to Rhodamine Red-PBAN C10 at 100 nM, none of the synthetic analogs exhibited PBANR binding at the same concentration. Taken together, our results demonstrate that the C2 Arg residue in BomPBAN is essential for PBANR binding and activation