We present the case for a dark matter detector with directional sensitivity. This document was developed at the 2009 CYGNUS workshop on directional dark matter detection, and contains contributions from theorists and experimental groups in the field. We describe the need for a dark matter detector with directional sensitivity; each directional dark matter experiment presents their project's status; and we close with a feasibility study for scaling up to a one ton directional detector, which would cost around $150M.
A direction-sensitive dark matter search experiment at Kamioka underground laboratory with the NEWAGE-0.3a detector was performed. The NEWAGE-0.3a detector is a gaseous micro-time-projection chamber filled with CF 4 gas at 152 Torr. The fiducial volume and target mass are 20 × 25 × 31 cm 3 and 0.0115 kg, respectively. With an exposure of 0.524 kg·days, improved spin-dependent weakly interacting massive particle (WIMP)-proton cross section limits by a direction-sensitive method were achieved including a new record of 5400 pb for 150 GeV/c 2 WIMPs. We studied the remaining background and found that ambient γ-rays contributed about one-fifth of the remaining background and radioactive contaminants inside the gas chamber contributed the rest.
Human gamma interferon produced by recombinant Escherichia coli was degraded by endogenous protease after cell disruption. Specific cleavages took place at the center of two pairs of basic amino acids (Lys-131-Arg-132 and Arg-142-Arg-143) in the C-terminal region, giving rise to products with moleular weights of 17,500 and 16,000. The proteolytic activity was associated with the outer membrane ofE. coli. It was insensitive to the protease inhibitors diisopropylfluorophosphate, phenylmethylsulfonyl fluoride, tosyl-L-lysive chloromethyl ketone, EDTA, and p-chloromercuribenzoate. Benzamidie and the bivalent cations Zn2+ and Cu2+ inhibited the activity. Dynorphin A(1-13) (Tyr-Gly-Gly-Phe-Leu-Arg-Arg-Ile-Arg-Pro-Lys-Leu-Lys) was a good substrate and was preferentially cleaved at the center of Arg-6-Arg-7. Neither the amino nor carboxyl sides of Arg-9 and Lys-11 were digested. These results indicate that the protease spefically clkves the peptide bond between consecutive basic residues and therefore is different from the known membrane enzymes, proteases IV, V, and VI. We have designated this new enzyme protease VII.It is known that Escherichia coli contains a variety of membrane-bound proteolytic enzymes. Several lines of evidence indicate that these enzymes may play an important role in bacterial cell physiology. Specific cleavage reactions, such as the cleavage of colicins Ia, A, and Al to inactive polypeptide fragments (1), the cleavage of plasminogen to plasmin (9), caseinolytic activity (20), nitrate reductasesolubilizing activity (11), and ferric enterobactin receptormodifying activity (5), have been reported to be carried out by membrane preparations from E. coli. The purification and characterization of two membrane enzymes (protease IV and protease V) which are capable of degrading alkylated and high-molecular-weight cytoplasmic proteins have been reported by Pacaud (17). Protease IV has been identified by Ichihara et al. (6) as a signal peptide peptidase which degrades the signal peptide after its release from prolipoprotein by the signal peptidase during the maturation and export process. Additionally, Palmer and St. John have identified another membrane-associated protease termed protease VI (19). Protease VI is a serine protease located at the outer membrane of the cells and generates acid-soluble fragments from a mixture of E. coli membrane proteins. It may play a role in the turnover of E. coli membrane proteins, but the physiological role has not been identified.In the course of our investigations into the production of human gamma inteferon (4) in E. coli by recombinant DNA technology, we found a novel proteolytic activity in E. coli lysate. The human gamma interferon accumulated to a level about 10 to 15% that of the total E. coli proteins at the end of cultivation and was found to have undergone proteolytic cleavage in the C-terminal region after the cells were harvested and disrupted. The localization, inhibitor profile, and substrate specificity of the proteolytic enzyme revealed that it is a nov...
The antioxidant activity of the crude extract prepared from oregano (Origanum vulgare L.) and its antiinflammatory activities in mouse models of stressinduced gastritis and contact hypersensitivity were investigated. Oregano extract was a substrate for peroxidase, similar to phenol. Oregano extract exhibited iron-reducing activity, although its strength was approximately one-fifth of that of ascorbic acid. Oral administration of oregano extract significantly prevented mouse gastritis induced by cold-restraint stress. Percutaneous administration of oregano extract also significantly prevented mouse contact hypersensitivity induced by oxazolone. These antiinflammatory activities of oregano extract tended to be weaker than those of hydrocortisone. The antioxidant activities of oregano extract appear to contribute to its preventive effects against inflammatory diseases, such as stressinduced gastritis and contact hypersensitivity in mice.
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