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The use of hair roots as experimental samples has been a research focus for understanding the effects of spaceflight on astronauts, because it has many advantages, one of which is the fact that hair matrix cells actively divide in a hair follicle and sensitively reflect the physical conditions of the human body. In 2009, a research program focusing on the analysis of astronauts’ hairs was initiated to examine the effects of long-term spaceflight on the gene expression and mineral metabolism in the human body. Since the number of samples per astronaut is limited to 5 strands of hairs at each sampling point, due to the ethical viewpoint of astronauts or limited resources in space, it is important to develop an effective method for the molecular analysis of small amounts of hair roots. In this study, mRNA successfully extracted from 1, 5, and 10 hair follicles was amplified and subjected to the DNA microarray analysis to compare the gene expression within subjects. The results indicated that (1) it was possible to perform the genetic analysis on hair samples stored at -80℃, even without a fixation buffer and (2) the newly modified method of mRNA extraction and analysis was effective in detecting differential gene expression in samples containing only 5 hairs. In conclusion, RNA was efficiently extracted from 5 hair roots, which is the same number of hair roots used in the space experiment; therefore, this method can be applied to genetically analyze astronauts’ hair samples.

Accepted: 2016-02-19, 資料番号: SA1160030000

Space-borne astronomical instruments require extensive characterization on the ground before launch. In the hard X-ray region however, it is difficult for a laboratory-based beamline using a conventional X-ray source to provide a capability sufficient for pre-flight high-precision calibration. In this paper, we describe an experiment to characterize a hard X-ray telescope at a synchrotron facility, mainly on the basis of experimental setup and examples of measured results. We have developed hard X-ray telescopes consisting of Wolter-I grazing incidence optics and platinum-carbon multilayer supermirror coatings. The telescopes have been characterized at the synchrotron facility SPring-8 beamline BL20B2. The measurements at BL20B2 have great advantages such as extremely high flux, large-sized and less-divergent beam, and monochromatic beam covering the entire hard X-ray region from 8 to over 100 keV. The telescope was illuminated by monochromatic hard X-rays, and the focused image was measured by high resolution hard X-ray imagers. The entire telescope aperture was mapped by a small beam, and the effective area and the point spread function were obtained as well as local optical properties for further diagnostics of the characteristics of the telescope.

Snakin-1 (SN-1) is a small cysteine-rich plant antimicrobial peptide with broad spectrum antimicrobial activity which was isolated from potato (Solanum tuberosum). Here, we carried out the expression of a recombinant SN-1 in the methylotrophic yeast Pichia pastoris, along with its purification and characterization. A DNA fragment encoding the mature SN-1 was cloned into pPIC9 vector and introduced into P. pastoris. A large amount of pure recombinant SN-1 (approximately 40 mg/1L culture) was obtained from a fed-batch fermentation culture after purification with a cation exchange column followed by RP-HPLC. The identity of the recombinant SN-1 was verified by MALDI-TOF MS, CD and (1)H NMR experiments. All these data strongly indicated that the recombinant SN-1 peptide had a folding with six disulfide bonds that was identical to the native SN-1. Our findings showed that SN-1 exhibited strong antimicrobial activity against test microorganisms and produced very weak hemolysis of mammalian erythrocytes. The mechanism of its antimicrobial action against Escherichia coli was investigated by both outer membrane permeability assay and cytoplasmic membrane depolarization assay. These assays demonstrated that SN-1 is a membrane-active antimicrobial peptide which can disrupt both outer and cytoplasmic membrane integrity. This is the first report on the recombinant expression and purification of a fully active SN-1 in P. pastoris.

The International Linear Collider: A Technical Progress Report marks the halfway point towards the Global Design Effort fulfilling its mandate to follow up the ILC Reference Design Report with a more optimised Technical Design Report (TDR) by the end of 2012. The TDR will be based on much of the work reported here and will contain all the elements needed to propose the ILC to collaborating governments, including a technical design and implementation plan that are realistic and have been better optimised for performance, cost and risk. We are on track to develop detailed plans for the ILC, such that once results from the Large Hadron Collider (LHC) at CERN establish the main science goals and parameters of the next machine, we will be in good position to make a strong proposal for this new major global project in particle physics. The two overriding issues for the ILC R&D programme are to demonstrate that the technical requirements for the accelerator are achievable with practical technologies, and that the ambitious physics goals can be addressed by realistic ILC detectors. This GDE interim report documents the impressive progress on the accelerator technologies that can make the ILC a reality. It highlights results of the technological demonstrations that are giving the community increased confidence that we will be ready to proceed with an ILC project following the TDR. The companion detector and physics report document likewise demonstrates how detector designs can meet the ambitious and detailed physics goals set out by the ILC Steering Committee. LHC results will likely affect the requirements for the machine design and the detectors, and we are monitoring that very closely, intending to adapt our design as those results become available.

The development of hard X-ray focusing optics for astrophysical observation is widely recognized as one of key technologies for future X-ray satellite missions. Utilizing InFOCμS balloon-borne experiment, we have developed thin-foil-nested hard X-ray telescope employing depth-graded Pt/C multilayer. Pre-flight calibration of the hard X-ray telescope for the 2004 flight was performed at X-ray beamline facilities in ISAS/JAXA and SPring-8. The effective area and image quality were estimated to be 51 cm 2 and 2.4 arcmin (half power diameter) at 30 keV, respectively. Limiting factors of its performance also investigated. And we revealed that the main factor was image degradation of an individual reflector. Based on such an investigation we are now continuously developing advanced hard X-ray telescope for future balloon experiments. From evaluation of upgraded test telescope, we get a response toward high resolution telescope in future years.

As technological and scientific path-finder towards future observatory missions, a balloon-born hard X-ray imaging observation experiment InFOCμS has been developed. The payload has flown four times since 2000. In its 2004 Fall flight campaign InFOCμS successfully achieved first scientific observations of multiple astronomical objects from galactic compacts to cluster of galaxies. Significant signal has been detected from bright galactic objects while analysis of extragalactic objects is underway. InFOCμS plans additional and upgraded telescope-detector system as early as 2006. High energy telescope for nuclear gamma-ray line observations is under planning.

A Four-stage X-ray Telescope (FXT) has been developed as the best-fit optics for the Diffuse Intergalactic Oxygen Surveyor (DIOS) mission, a small satellite mission for mapping observations of the warm-hot intergalactic medium. The FXT mirrors are based on a conical approximation of the Wolter-I design, fabrication technique used in the Suzaku satellite. We developed processes for fabricating a large-diameter (≥ 50 cm) foil mirror and made a new full size quadrant housing 60 cm in diameter with four-stage integrated alignment plates. We made optical measurement using one set of four-stage mirrors over than diameter of more than 50 cm.

This paper presents characterization of hard X-ray telescope using synchrotron facility, mainly on experimental setup, benefits of such experiment, and measurement results only available by means of bright synchrotron light. We have developed hard X-ray telescope consisting of Wolter-I grazing incidence optics with platinum-carbon multilayer supermirror surfaces. Telescopes have been fabricated for InFOCuS balloon experiment, and we achieved first scientific flight in 2004. The hard X-ray telescope on board InFOCuS has been characterized at synchrotron facility SPring-8/BL20B2, Japan. Measurement at BL20B2 has great advantages such as extremely high flux, large sized and less divergent beam, and monochromatic beam covering entire hard X-ray region from 8 to over 100keV. A 16m-long experiment hutch is another feature suitable for measurements of hard X-ray telescopes. The telescope was illuminated by monochromatic hard X-rays, and focused image was measured by high resolution hard X-ray imager. Whole telescope aperture was mapped by small beam, and effective area and point spread function are obtained as well as local optical properties for further diagnostics of telescope characteristics.

Hard X-ray focusing observation is important to reveal non-thermal emission mechanism and origin in active galaxies and clusters of galaxies. We have carried out the hard X-ray observation throughout the ¥infocus program, which is an international balloon-borne experiment in collaboration with NASA/GSFC and Nagoya University. The telescope is conical approximation of Wolter-I optics with 8 m focal length and 40 cm diameter. It consists of 255 nested thin (0.17 mm thickness) reflectors with incidence angles of 0.10° to 0.36°. Reflectors are coated with depth-graded platinum-carbon (Pt/C) multilayers, so-called supermirrors, with periodic length of 2.6 to 13 nm and bi-layer number of 28 to 79, depending on incidence angles. We are now continuously fabricating advanced next hard X-ray telescope for the second ¥infocus flight in 2004. Compared with the first telescope, the following improvements have been made on the second one. Supermirror reflectors have wider sensitivity in energy band of 20-60 keV adopting optimum supermirror design for balloon observation, and smaller interfacial roughness owing to complete replication technique. For upgrading of the image quality, we then adopted stiffer reflector substrate, selected replication mandrel with better shape, and the modified telescope housing with higher alignment accuracy for reflectors. The performance of the new hard X-ray telescope was measured in X-ray beamline facility in ISAS/JAXA and synchrotron radiation facility SPring-8. The effective area and image quality are obtained to be 45 cm2 at 30 keV and 23 cm2 at 40 keV, and 2.5 arcmin in half power diameter, respectively. In this paper we report our development of the upgraded hard X-ray telescope for the second balloon flight experiment.

We have been developing the hard X-ray telescope for balloon borne experiment named InFOC µ S. The “rstInFOC µ S ”ight was carried out on July, 2001. In this ”ight, we obtained hard X-ray image of Cygnus X-1 above20 keV. This is “rst observation with hard X-ray telescope using multilayers. In this mission, the platinum-carbondepth graded multilayers (supermirror) are used as X-ray re”ectors combining multi nested thin foil optics toobtain enough eciency in the hard X-ray region. They make us possible to obtain 40 cm 3 eective area at 30keV with 40 cm diameter of the telescope.After the “rst ”ight, the hard X-ray telescope was recoveredwithout any damages, we measured performancesof the telescope in synchrotron radiation facility SPring-8. We obtained the results, the half power diameter(HPD) is 2.4 arcmin and eective area is 38 cm 2 at 30 keV. These results show that no degradation of theperformances of the hard X-ray telescope was observed in this measurement.Furthermore, We begin to fabricate new hard X-ray telescope for future InFOC µ S ”ight. The design of themultilayer supermirrors are improved to widen the energy band. The performances of this telescope includingeective area and spatial resolution are measured using synchrotron radiation facility SPring-8 and ISAS 30 mX-ray beam line. The measured eectiv e area is signi“can tly larger than the “rst telescope especially above 30keV.Keywords: hard X-ray, multilayer, supermirror, telescope, balloon