Observation of Allende and Antarctic meteorites by monochromatic X-ray CT based on synchrotron radiation

Three-dimensional CT images of the Allende meteorite with a high resolution of 10μm have been obtained nondestructively by a monochromatic X-ray computed tomography (CT) based on synchrotron radiation (SR). The metallic minerals, matrix and chondrules can be clearly observed in the CT images. The CT values, which express the image intensity, allow a quantitative elemental analysis including such as difference in the metallic minerals, i. e., pentlandite and troilite, using the comparison of CT images and elemental images measured by a computer-aided microanalyzer (CMA). The three-dimensional CT images indicate that the metallic minerals surround some chondrules, and the largest chondrule has two humps and well crystallized olivine in its center. These observations suggest that the three-dimensional SR-CT system is a useful method for identification of internal structures of stony meteorites. Additionally, information obtained from the CT images of Antarctic meteorites confirms that the SR-CT system can be applied to classification of stony chondrites

ムセン LAN ヲ モチイタ GPSデータ エンカク カイシュウ システム ノ カイハツ

無線LANを利用した2周波GPSデータ遠隔回収システムを開発した.このシステムは,GPSロガーとデータ送信装置からなる地上観測装置とデータ回収装置で構成され,コマンド送受信にはZigBee通信(2.4 GHz, 250 Kbps)を, GPSデータの送受信には無線LAN通信(2.4 GHz, 54 Mbps)を使用する.GPSロガーで収録された1秒サンプリングデータから毎日作成される30秒サンプリングデータファイルが送信される. これまで,(1)地上でのデータ回収試験,(2) 小型無人飛行機によるデータ回収試験,(3) 昭和基地・西の浦での実データ回収試験を実施した.(1) では,最大400 m 程度の距離で全データを回収でき,(2) では約250 m 以下の高さで飛行する飛行機により約24.5 MB のデータを回収できた.(3) では,10 分以内に約23.5 MB のGPS ブイデータの回収に成功しており,観測を止めることなくデータ回収が可能となった.A remote retrieval system, using a wireless LAN, was developed to retrieve dual-frequency GPS data. The system consists of a ground observation unit (comprising a dual-frequency GPS logger and a data transmission unit) and a data retrieval unit. In this system, we use the ZigBee communication protocol to transmit control commands (2.4 GHz, 250 Kbps) and a wireless LAN communication to transmit GPS data (2.4 GHz, 54 Mbps). Data of every 30 seconds to transmit to the data retrieval unit are re-sampled from 1-second data at 00 UT each day. We conducted three data-transmission tests with the system: (1) a ground data retrieval test, (2) a data retrieval test from the atmosphere of a few hundred meters high using a small unmanned aircraft, and (3) actual GPS-data retrieval tests from a GPS buoy deployed on sea ice at Nisi-no-ura Cove, Syowa Station, Antarctica. In test (1), we successfully received all the data from the ground observation unit when situated at distances of less than 400 m from the data retrieval unit. In test (2), we obtained approximately 24.5 MB of data from the aircraft at heights of less than 250 m. In test (3), we obtained approximately 23.5 MB of data from the GPS buoy within 10 minutes. The proposed system has the advantage of enabling continuous measurements without aborting the measurement at the data retrievals

Autoantibodies against matrix metalloproteinase-1 in patients with localized scleroderma

Background: Localized scleroderma (LSc) is characterized by cutaneous fibrosis and various autoantibodies. Objective: To determine the presence or levels of antibodies (Abs) against matrix metalloproteinase (MMP)-1 and their clinical relevance in LSc. Methods: Anti-MMP-1 Ab was examined by ELISA (Enzyme-Linked ImmunoSorbent Assay) and immunoblotting using human recombinant MMP-1. MMP-1 collagenase activity was determined using biotinylated collagen as substrate and the amount of cleaved biotinylated fragments of collagen by MMP-1 was measured by ELISA. Results: LSc patients exhibited significantly elevated IgG anti-MMP-1 Ab levels relative to normal controls at similar level of patients with systemic sclerosis (SSc). However, IgG anti-MMP-1 Ab levels were comparable among the 3 LSc subgroups: morphea, linear scleroderma, and generalized morphea. When absorbance values higher than the mean + 2S.D. of normal controls were considered positive, IgG or IgM anti-MMP-1 Ab was found in 46% and 49% of total LSc patients and SSc patients, respectively. Anti-MMP-1 Ab was detected most frequently in morphea patients (60%), followed by linear scleroderma patients (47%) and then generalized morphea patients (25%). LSc patients positive for IgG anti-MMP-1 Ab had elevated levels of IgG anti-single-stranded DNA Ab, IgG anti-nucleosome Ab, and shorter disease duration relative to those negative. The presence of anti-MMP-1 Ab in LSc patients was confirmed by immunoblotting. IgG isolated from LSc patients\u27 sera positive for IgG anti-MMP-1 Ab by ELISA inhibited MMP-1 collagenase activity. Conclusion: These results suggest that anti-MMP-1 autoantibody is a novel autoantibody in LSc. c 2008 Japanese Society for Investigative Dermatology

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements