Crystallographic Characterization of Extraterrestrial Materials by Energy-Scanning X-ray Diffraction

We have continued our long-term project using X-ray diffraction to characterize a wide range of extraterrestrial samples. The stationary sample method with polychromatic X-rays is advantageous because the irradiated area of the sample is always same and fixed, meaning that all diffraction spots occur from the same area of the sample, however, unit cell parameters cannot be directly obtained by this method though they are very important for identification of mineral and for determination of crystal structures. In order to obtain the cell parameters even in the case of the sample stationary method, we apply energy scanning of a micro-beam of monochromatic SR at SPring-8

The effect of isoflavone-daidzein oral medication on cutaneous wound healing in female ovariectomized mice

This study investigated the influence of oral administration of isoflavone-daidzein on the cutaneous wound healing process in female ovariectomized mice. Eight-week-old female mice were divided into groups of ovariectomized mice and mice administered daidzein after an ovariectomy. Two full-thickness wounds on the dorsum were made in mice in both groups. There was no significant difference between wound areas of the two groups from wounding to healing during 15 days. The area in the group administered daidzein tended to be smaller than that in the ovariectomized group during the inflammatory phase 4 and 5 days after wounding . The rate of re-epithelialization in the group administered daidzein tended to be higher than that in the ovariectomized group in the inflammatory phase on day 3 (40.7 ± 17.6% and 21.0 ± 16.8%, respectively). Therefore, the administration of daidzein under lack of estrogen is expected to reduce the inflammation period and promote re-epithelialization. この研究は、卵巣摘出した雌マウスに皮膚創傷を作製し、経口投与したイソフラボン の一種であるダイゼインが、創傷治癒にどのような影響を与えるかを観察したもので ある。8 週令の雌マウスを卵巣摘出群と卵巣摘出し創作製した後にダイゼインを与え た2 群に分けた。両群共、卵巣摘出後、ダイゼインを含まない精製飼料で２週間飼育 後に、左右の背部に直径4mm の皮膚全層欠損層を作製した。創作製後、ダイゼインを 含まない飼料とダイゼインを含む飼料で2 週間飼育した。ダイゼインは、飼料1g に 0.01mg 含むように作製した。両群の創面積は、2 週間の間の毎日において、有意差は 見られなかった。しかし、炎症期である創作製後4 と5 日では、ダイゼイン食で飼育 した群が無ダイゼイン食で飼育した群が、やや創面積が小さい傾向がみられた（それ ぞれ、p 値が0.061、0.083 であった）。創作製後の3 日での、再上皮化の割合は、ダイゼイン群で40.7 ± 17.6%、無ダイゼイン群で21.0 ± 16.8%となり、ダイゼイ ン群はより上皮化が進んでいる傾向が見られた (p = 0.07)。これらの結果は、エス トロゲン欠乏状態で、ダイゼインの経口投与が、創傷治癒において、炎症を抑制し上 皮化を促進することを示唆している

Measuring the Shock Stage of Asteroid Regolith Grains by Electron Back-Scattered Diffraction

We have been analyzing Itokawa samples in order to definitively establish the degree of shock experienced by the regolith of asteroid Itokawa, and to devise a bridge between shock determinations by standard light optical petrography, crystal structures as determined by electron and X-ray diffraction. These techniques would then be available for samples returned from other asteroid regoliths

Measuring Shock Stage of ltokawa Regolith Grains by Electron Back-Scattered Diffraction and Synchrotron X-Ray Diffraction

We have been analyzing Itokawa samples in order to definitively establish the degree of shock experienced by the regolith of asteroid Itokawa, and to devise a bridge between shock determinations by standard light optical petrography, crystal structures as determined by electron and X-ray diffraction techniques. We are making measurements of olivine crystal structures and using these to elucidate critical regolith impact processes. We use electron back-scattered diffraction (EBSD) and synchrotron X-ray diffraction (SXRD). We are comparing the Itokawa samples to L and LL chondrite meteorites chosen to span the shock scale experienced by Itokawa, specifically Chainpur (LL3.4, Shock Stage 1), Semarkona (LL3.00, S2), Kilabo (LL6, S3), NWA100 (L6, S4) and Chelyabinsk (LL5, S4). In SXRD we measure the line broadening of olivine reflections as a measure of shock stage. In this presentation we concentrate on the EBSD work. We employed JSC's Supra 55 variable pressure FEG-SEM and Bruker EBSD system. We are not seeking actual strain values, but rather indirect strain-related measurements such as extent of intra-grain lattice rotation, and determining whether shock state "standards" (meteorite samples of accepted shock state, and appropriate small grain size) show strain measurements that may be statistically differentiated, using a sampling of particles (number and size range) typical of asteroid regoliths. Using our system we determined that a column pressure of 9 Pa and no C-coating on the sample was optimal. We varied camera exposure time and gain to optimize mapping performance, concluding that 320x240 pattern pixilation, frame averaging of 3, 15 kV, and low extractor voltage yielded an acceptable balance of hit rate (>90%), speed (11 fps) and map quality using an exposure time of 30 ms (gain 650). We found that there was no strong effect of step size on Grain Orientation Spread (GOS) and Grain Reference Orientation Deviation angle (GROD-a) distribution; there was some effect on grain average Kernel Average Misorientation (KAM) (reduced with smaller step size for the same grain), as expected. We monitored GOS, Maximum Orientation Spread (MOS) and GROD-a differences between whole olivine grains and sub-sampled areas, and found that there were significant differences between the whole grain dataset and subsets, as well as between subsets, likely due to sampling-related "noise". Also, in general (and logically) whole grains exhibit greater degrees of cumulative lattice rotation. Sampling size affects the apparent strain character of the grain, at least as measured by GOS, MOS and GROD-a. There were differences in the distribution frequencies of GOS and MOS between shock stages, and in plots of MOS and GOS vs. grain diameter. These results are generally consistent with those reported this year. However, it is unknown whether the differences between samples of different shock states exceeds the clustering of these values to the extent that shock stage determinations can still be made with confidence. We are investigating this by examination of meteorites with higher shock stage 4 to 5. Our research will improve our understanding of how small, primitive solar system bodies formed and evolved, and improve understanding of the processes that determine the history and future of habitability of environments on other solar system bodies. The results will directly enrich the ongoing asteroid and comet exploration missions by NASA and JAXA, and broaden our understanding of the origin and evolution of small bodies in the early solar system, and elucidate the nature of asteroid and comet regolith

〔伝統的な言語文化〕の学習指導改善 －落語教材の検討を通して－

Review of the book Leimon: Studies Presented to Lennart Rydén on his Sixty-Fifth Birthday (edited by Jan Olof Rosenqvist)

Current status of space gravitational wave antenna DECIGO and B-DECIGO

Deci-hertz Interferometer Gravitational Wave Observatory (DECIGO) is the future Japanese space mission with a frequency band of 0.1 Hz to 10 Hz. DECIGO aims at the detection of primordial gravitational waves, which could be produced during the inflationary period right after the birth of the universe. There are many other scientific objectives of DECIGO, including the direct measurement of the acceleration of the expansion of the universe, and reliable and accurate predictions of the timing and locations of neutron star/black hole binary coalescences. DECIGO consists of four clusters of observatories placed in the heliocentric orbit. Each cluster consists of three spacecraft, which form three Fabry-Perot Michelson interferometers with an arm length of 1,000 km. Three clusters of DECIGO will be placed far from each other, and the fourth cluster will be placed in the same position as one of the three clusters to obtain the correlation signals for the detection of the primordial gravitational waves. We plan to launch B-DECIGO, which is a scientific pathfinder of DECIGO, before DECIGO in the 2030s to demonstrate the technologies required for DECIGO, as well as to obtain fruitful scientific results to further expand the multi-messenger astronomy.Comment: 10 pages, 3 figure

Current status of space gravitational wave antenna DECIGO and B-DECIGO

The Deci-hertz Interferometer Gravitational Wave Observatory (DECIGO) is a future Japanese space mission with a frequency band of 0.1 Hz to 10 Hz. DECIGO aims at the detection of primordial gravitational waves, which could have been produced during the inflationary period right after the birth of the Universe. There are many other scientific objectives of DECIGO, including the direct measurement of the acceleration of the expansion of the Universe, and reliable and accurate predictions of the timing and locations of neutron star/black hole binary coalescences. DECIGO consists of four clusters of observatories placed in heliocentric orbit. Each cluster consists of three spacecraft, which form three Fabry–Pérot Michelson interferometers with an arm length of 1000 km. Three DECIGO clusters will be placed far from each other, and the fourth will be placed in the same position as one of the other three to obtain correlation signals for the detection of primordial gravitational waves. We plan to launch B-DECIGO, which is a scientific pathfinder for DECIGO, before DECIGO in the 2030s to demonstrate the technologies required for DECIGO, as well as to obtain fruitful scientific results to further expand multi-messenger astronomy