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As photoemission plays a key role in surface potential of spacecraft materials in sunlight, the photoemission yield of spacecraft used polyimide film is required for surface potential analysis. To reveal the space environmental effects on the photoemission, the ground based degradations of polyimide film due to 500 keV electrons and 50 keV protons irradiation with 4 different fluences respectively, ultraviolet irradiation with 5 different doses, and atomic oxygen beam erosion with 2 different fluences were conducted separately. By using a developed measuring system, we measured the photoemission yield of the virgin and the 4 kinds of degraded polyimide films respectively and compared the results. It is inferred that, the variation of photoemission yield was obvious after electrons, protons and ultraviolet irradiation but slight for atomic oxygen erosion. The variation of photoemission yield has been explained from the viewpoint of surface reflectance, roughness, and the free radical concentration of the exposed samples. Besides, the Monte-Carlo analysis software Casino and SRIM were used to analysis the distribution and stopping power of electron and proton respectively. It is considered that, the degradation mechanism is the multiple effects of reflectance, free radicals and so forth.

The concept of taking conflict personally is largely underexplored by dominant conflict literature. The purpose of this study was to test the cross-cultural predictions of the associations between self-construal, the tendency to personalize conflict, and subsequent outcome variables such as negative feelings of being criticized and motivation to improve. The participants were 457 undergraduates, of which 185 were studying in Japan, and 272 were studying in the United States. The results indicated the significant negative relation between independent self-construal and taking conflict personally. On the contrary, interdependent self and taking conflict personally showed positive relation. In turn, taking conflict personally indicated positive relation with participants’ conflict management style, such as motivation to improve one’s own behaviors. Discussion of these results and their implications is provided.

Polymers used on low earth orbit (LEO) spacecraft surface suffer from an ultraviolet (UV) irradiation and orbital atomic oxygen (AO) erosion. These degradations may change the total electron emission yield (TEEY) of the materials and ultimately result in unexpected surface charging. In this paper, we chose polyimide (PI) film, a thermal control material, and carried out two types of ground-based degradation. The degradation methods were UV irradiation with five different equivalent solar hours, and AO erosion with two fluences equivalent to 0.5 and 1 year LEO flight time, respectively. Using an Auger microscope-based TEEY measurement system with a scanning measuring method, the TEEY of virgin and degraded PI films were tested and analyzed comparatively. The X-ray photoelectron spectrum, field-emission scanning electron microscope, and computational simulations were also used for element bonds analysis, roughness imaging, and electron depth calculation to discover the mechanisms of the degradation and their effects on the TEEY of the material.

The establishment of symbiotic associations in plants requires calcium oscillations that must be decoded to invoke downstream developmental programs. In animal systems, comparable calcium oscillations are decoded by calmodulin (CaM)–dependent protein kinases, but symbiotic signaling involves a calcium/CaM–dependent protein kinase (CCaMK) that is unique to plants. CCaMK differs from the animal CaM kinases by its dual ability to bind free calcium, via calcium binding EF-hand domains on the protein, or to bind calcium complexed with CaM, via a CaM binding domain. In this study, we dissect this dual regulation of CCaMK by calcium. We find that calcium binding to the EF-hand domains promotes autophosphorylation, which negatively regulates CCaMK by stabilizing the inactive state of the protein. By contrast, calcium-dependent CaM binding overrides the effects of autophosphorylation and activates the protein. The differential calcium binding affinities of the EF-hand domains compared with those of CaM suggest that CCaMK is maintained in the inactive state at basal calcium concentrations and is activated via CaM binding during calcium oscillations. This work provides a model for decoding calcium oscillations that uses differential calcium binding affinities to create a robust molecular switch that is responsive to calcium concentrations associated with both the basal state and with oscillations.

LTR retrotransposons are closely related to retroviruses and their activities shape eukaryotic genomes. Here, we present a complete Lotus japonicus insertion mutant collection generated by identification of 640,653 new insertion events following de novo activation of the LTR element Lotus retrotransposon 1 (LORE1) ( http : // lotus .au . dk). Insertion preferences are critical for effective gene targeting, and we exploit our large data set to analyse LTR element characteristics in this context. We infer the mechanism that generates the consensus palindromes typical of retroviral and LTR retrotransposon insertion sites, identify a short relaxed insertion site motif, and demonstrate selective integration into CHG-hypomethylated genes. These characteristics result in a steep increase in deleterious mutation rate following activation, and allow LORE1 active gene targeting to approach saturation within a population of 134,682 Lotus japonicus lines. We suggest that saturation mutagenesis using endogenous LTR retrotransposons with germinal activity can be used as a general and cost-efficient strategy for generation of non-transgenic mutant collections for unrestricted use in plant research. This article is protected by copyright. All rights reserved.

This paper includes evaluations of composite tanks or pressure vessels based on fracture mechanics and an improved method for tank design. Problems of exfoliation between the mouthpiece and composite in current composite pressure vessels are shown, and the simple solution by inducing a slit into the mouthpiece near the bonding interface is proposed. The effect of the slit is evaluated using a geometrically simple model as well as a pressure vessel model designed for a rocket.

Enterohemorrhagic Escherichia coli (EHEC) delivers virulence factors into host cells through the type III secretion system (T3SS) to exert the bacterial pathogenicity. EHEC encodes more than 20 type III secretion system-delivered families of effectors that have different functions at different infectious stages and enable a successful infection. One of them, EspL2, is encoded on the SpLE3 phage-like element in EHEC O157:H7 Sakai and is well conserved among various EHEC strains. Here we show that, after delivery into host cells, EspL2 accumulated under adherent bacteria, as did polymerized F-actin. EspL2-expressing EHEC formed three-dimensional, condensed microcolonies, into which the host cell extended plasma membrane protrusions on an F-actin-rich cytoskeleton. EspL2 bound F-actin-aggregating annexin 2 directly, increasing its activity. In addition, annexin 2 depletion abolished the EspL2-dependent formation of condensed microcolonies and F-actin aggregation. The EspL2-induced pseudopod-like protrusion of the host plasma membrane interacted with and supported colonization by the bacteria, independent of Tir-mediated actin polymerization. Thus, EspL2 supports efficient colonization by increasing annexin 2's ability to aggregate Tir-induced F-actin and by modifying the morphology of the host cell membrane.

真空の科学と技術，大気の圧力の研究などのグエリケの業績は大変大きいにも関わらず，その全貌は不十分にしか紹介されていなかった．これは一つには彼が馬を用いて行ったマグデブルグの半球の実験があまりにも有名すぎたせいかもしれない．特にこの事情は我が国において著しいので，著者は 1. 叙説に続く 2. において現在得られる情報によりグエリケの伝記の概略を紹介することを試みた．さらに 3. において，彼の著作を中心に科学的業績について略説する．最後に 4. の結語において今後検討すべき課題について述べる．なお日本の文献は殆どが生まれたときの名前である Otto Gericke の姓であるゲーリケと書いてあるのに，本稿では“グエリケ”としたのは，現在欧米の文献は1666年の神聖ローマ帝国貴族の叙爵後の名前である Otto von Guericke を用いているから，それに従ったのである．

Enterohemorrhagic Escherichia coli is an emerging pathogen that causes diarrhea and hemolytic uremic syndrome. Much of the genomic information that affects virulence is acquired by horizontal transfer. Genes necessary for attaching and effacing lesions are located in the locus for enterocyte effacement (LEE) pathogenicity island. LEE gene transcription is positively regulated by Ler, which is also encoded by the LEE, and by Pch regulators, which are encoded at other loci. Here we identified genes whose transcription profiles were similar to those of the LEE genes, by comparing the effects of altering ler and pch transcript levels. We assigned these genes into two classes, according to their transcription profiles. By determining the binding profiles for Ler and Pch, we showed that both were involved in regulating one class of genes, but only Pch was involved in regulating the other class. Binding sites were found in the coding region as well as the promoter region of regulated genes, which include genes common to K12 strains as well as 0157-specific genes, suggesting that both act as a global regulator. These results indicate that Ler and Pch orchestrate the transcription of virulence genes, which are captured by horizontal transfer and scattered throughout the chromosome.

It is more than 40 years since 1960, when the first meeting of Symposium was convened. In these 40 years, human knowledge about plasma physics has increased enormously and technology has advanced a great deal to solve fusion energy problems, mainly thanks to the efforts of the Symposium member countries. Therefore, it is thought worthwhile to provide a written history of SOFT, which is practically representing the history of fusion research. Nowadays, the Symposium history suffers from the fact that it lacks formal records of its first few meetings. Because of this lack of formal records, it is difficult to know what technical and scientific subjects were discussed at those early meetings and what technological difficulties were recognized at such the first few SOFT meetings. We are not able to know what were agreed upon to solve the technological difficulties. This is the reason why I began gathering the records of the first few Symposium meetings. The efforts and difficulties I have made and encountered, respectively, are described in this paper. Time passes rapidly and it is becoming more and more difficult for me to complete my work. Therefore, since the Symposium usually has met in Europe, I wish European colleagues to read my paper, and would appreciate the importance of this problem. I am very glad if they take over the work from me.

This study presents the development and implementation of a photoelectron current measurement system on-board HORYU-IV satellite to take on-orbit measurements from conductive and insulator surfaces. The measurement system aims at providing critical information on photoelectron yield of materials widely used onboard spacecraft. HORYU-IV is the fourth satellites of the HORYU series developed at Kyushu Institute of Technology and it was piggy-back launched on-board H-IIA F30 rocket at an altitude of 575 km on February 17, 2016 (JST). The measurement system mainly consists of current-voltage amplifier circuits for AU, Kapton® and black Kapton® samples with gains of 1x, 3x and 1x amplification, respectively. In this article, the analysis of the on-orbit results is presented. The on-orbit results show that a photoelectron current of 2.9nA and 3.1nA was measured from black Kapton® sample at respective elevations of 70.7° and 71.1°. These results respectively correspond to a current density of 14.0μA/m2 and 18.0μA/m2 at 71.1°. This study also presents various ground-based tests results performed to verify and validate the effectiveness of the photoelectron current measurement system developed for space applications.

Among leguminous plants, the model legume Lotus japonicus (Regel) Larsen has many biological and genetic advantages. We have developed a genetic linkage map of L. japonicus based on amplified fragment length polymorphism (AFLP), simple sequence repeat polymorphism (SSRP) and derived cleaved amplified polymorphic sequence (dCAPS). The F2 mapping population used was derived from a cross between two L. japonicus accessions Gifu B-129 and Miyakojima MG-20. These parental accessions showed remarkable cytological differences, particularly with respect to size and morphology of chromosomes 1 and 2. Using fluorescence in situ hybridization (FISH) with BAC clones from Gifu B-129 and TAC (Transformation-competent Artificial Chromosome) clones from Miyakojima MG-20, a reciprocal translocation was found to be responsible for the cytological differences between chromosomes 1 and 2. The borders of the translocations were identified by FISH and by alignment toward the L. filicaulis x L. japonicus Gifu B-129 linkage map. The markers from the main translocated region were located on linkage groups 1 and 2 of the two accessions, Gifu B-129 and Miyakojima MG-20, respectively. The framework of the linkage map was constructed based on codominant markers, and then dominant markers were integrated separately in each linkage group of the parents. The resulting linkage groups correspond to the six pairs of chromosomes of L. japonicus and consist of 287 markers with 487.3 cM length in Gifu B-129 and 277 markers with 481.6 cM length in Miyakojima MG-20. The map and marker information is available through the World Wide Web at http://www.kazusa.or.jp/lotus/.

Traditionally, Koreans and Japanese have been considered collectivistic in their communication behavior, in comparison to U.S. Americans. However, the important cultural differences (possibly subtle) in conflict management styles among the two collectivist cultures have been overlooked. This article aims to explore how Japanese and Koreans may differ in their preferences for different conflict management styles, focusing on the importance attached to conversational constraints in conflict situations. This article focuses on the following four conversational constraints: (1) concern for clarity; (2) concern for minimizing imposition; (3) concern for avoiding hurting the hearers feelings; and (4) concern for avoiding negative evaluation by the hearer. Several hypotheses were formulated based on the origins behind the conversational constraints in relation to the cultural orientations of Japanese and Koreans. A total of 534 undergraduate students, studying in Japan N = 235) and Korea (N = 299), participated in the study. Each participant was provided descriptions of the three conflict situations and was asked to rate the perceived importance of each constraint in each conflict situation. The main findings of this study point to a picture that Koreans are more collectivistic in conflict communication styles than Japanese. Specifically, the results of this study seem to suggest different processes of conflict management in the two cultures: Japanese as focusing on clarity constraint (conveying the message clearly and efficiently) more than Koreans, and Koreans focusing on social-relation constraints (avoiding imposition to the hearer or loss of face by the hearer) more than Japanese.

Conformational properties of ethylene glycol, oligo-, and poly(ethylene oxide) ranging in weight-average molecular weight ( M w ) from 62 to 1.1 × 10 7 have been studied by static light scattering and viscometry in salt-free and 0.45 M K 2 SO 4 water and in benzene. Above M w = 6 × 10 3 , intrinsic viscosity ([η]) and z -average square radius of gyration (〈 S 2 〉 2 ) of PEO in a salt-free solution at 25°C, [η] = 4.33 × 10 −4 M w 0.67 9 dl g −1 and 〈 S 2 〉 z = 4.08 × 10 −18 M w 1.1 6 cm 2 , respectively. The second virial coefficient is positive in water at 25°C but one order of magnitude smaller than reported by Devanand et al. ( Macromolecules , 1991, 24 , 5943). A θ-temperature for PEO in 0.45 M K 2 SO 4 aqueous solution is determined to be 34.5°C and above M w = 4 × 10 2 , [η] and 〈 S 2 〉 z follow the power laws for an unperturbed polymer chain. The characteristic ratio ( C ∞ ) of PEO is 5.2 ± 0.1. 9.3Awas determined for the persistence length and 8.7A −1 for the molar mass per unit contour length of a PEO chain, based on the helical wormlike touched-bead model. The PEO chain in water behaves as a flexible polymer with a relatively large hydrodynamic diameter (9A) because of the hydration of the PEO chain.

The purpose of this study was to determine whether or not “self‐construals” (Markus & Kitayama, 1991) are an aspect of culture that accounts for the perceived importance of conversational constraints. To spell out the way in which culture influences communication styles, we developed a mediation model. The model assumes that the perceived importance of conversational constraints is determined by values, e.g., independent versus interdependent self‐construals, and that values (self‐construals) are determined in part by culture. Participants were 972 undergraduates studying in Korea, Japan, Hawai'i, and the mainland United States. After being presented with six situations, participants rated the perceived importance of each of three constraints in relation to each situation. They then completed a scale reflecting the independent and interdependent dimensions of their self‐construals. The results were consistent with the proposed mediation model. Culture‐level individualism influenced independent self‐constr...

従来大型コンピュータの上で多くの化学研究者たちによって利用されてきたX線結晶構造解析システムUNICSIIIをパーソナルコンピュータ・ワークステーションへ移植した。パーソナルコンピュータとしては32ビットMS-DOSマシン、ワークステーションとしてはUNIXマシンを対象とした。MS-DOSマシンでは15年前のFACOMの大型機に若干優る程度の実行速度を得られ、UNIXマシンにおいてはその数倍の速度と大型機におけるJCLに類似した環境を実現できた。結晶構造の画面への表示あるいは印刷の機能を持つプログラムを移植したことにより、手軽に結晶構造を表示・印刷させることができ、さらには図を文章中に容易に張り込むことができるようになった。

Comparisons of helium (He) transport and exhaust in L-mode and in an enhanced confinement regime (H-mode), which is induced by a polarizing electrode, have been made for the TEXTOR tokamak. The results show an increased tendency for He accumulation when bulk plasma energy and particle confinement are improved during the polarization induced H-mode. Since these results imply that a high He pumping efficiency may be necessary for H-mode burning plasmas, we have begun exploring He transport in a divertor H-mode, similar to that proposed for International Thermonuclear Experimental Reactor (ITER). A collaborative program has been initiated to measure He transport and scaling on DIII-D during L-mode, H-mode, and ELMing H-mode plasma conditions. To simulate the presence of He ash in DIII-D, a 25 ms He puff is injected into a DIII-D plasma resulting in a He concentration of {approx}5%. The time dependence of the He{sup 2+} density profiles in the plasma core is measured by charge-exchange recombination spectroscopy at 11 radial locations.

In this paper, a scaling law on the landing behavior of a lunar probe is discussed. In order to derive an effective scaling law, all of possible non-dimensional numbers, called pi-numbers, were examined at first based on the principle equations of physics related to the phenomena. One strict relationship was then derived in terms of the size between a real model and a corresponding scale model. The relationship suggests that the scale models should have the size of one sixth of the real ones when studying the motion behavior of mechanical systems on the Moon. The fact has been well known in the space community. However, such a strict law is not always practical in laboratory experiments on the ground. Therefore, possibilities to relax the law were investigated; hence two candidate relationships were obtained. Experiments in a vacuum chamber using simulated lunar soil were carried out to validate these relaxed laws, and concluded was that inertia forces and soil-cohesion forces dominate over gravity forces for the landing dynamics. Elimination of the gravity forces from the primary consideration in the scale model experiments will make the verification process of the lunar landing systems easy and more practical.

This paper describes effects of gravity on mobility performance of wheeled rovers for future lunar/planetary exploration missions. A series of model tests of a wheel‐terrain system were performed on an aircraft during variable gravity maneuvers, and it became clear that slip of the wheel becomes high when the gravity is less than 1/2G. In addition to the flight experiments, the same model tests were performed in a laboratory on the ground (1G condition). The experiments were demonstrated with variable wheel loads by using counterweights. As a result of the on‐ground experiments, the mobility performance under low wheel load conditions was found to be improved contrary to the flight experiments. In case of the flight experiments, not only the wheel load but also bearing in the terrain changes with respect to the gravity level, while only the wheel load changes in case of the on‐ground experiments. Thus, running under a reduced gravity condition becomes difficult because the terrain generates higher rolling...

A toroidal belt pump limiter has been designed, constructed, installed and operated in the TEXTOR tokamak. The Advanced Limiter TEST-II, or ALT-II, is carried out as a partnership under a joint agreement between the European Community, Japan and the United States. ALT-II is designed to withstand the high heat fluxes (greater than 500 W/cm 2 ) intrinsic to the boundary region of tokamak plasmas while simultaneously removing 5% to 10% of the core plasma efflux. The belt consists of eight segments, each 28 cm wide, 150 cm long, and 1.2 cm thick, and each is covered with shaped graphite tiles. Mounted behind each blade is a “scoop” system which captures plasma flowing past the leading edges and behind the blades. This plasma neutralizes on a collector plate and the resulting neutral gas is pumped. During ohmic discharges, 50 to 60 A of current is collected in the scoops and removal rates up to 0.25 Torr-l/s are achieved. The blades are instrumented with Langmuir probes and thermo couples, and other diagnostics include infrared cameras, H α -monitors, pressure gauges, helium charge exchange spectroscopy, and helium gas diagnostics. The plasma edge and the operation of the pump limiter system are described.

In TEXTOR helium removal experiments with the pump-limiter ALT-II have started. To simulate the presence of helium ash in the plasma, helium is injected into the discharge (e.g. at t = 0.7s) as a short pulse of Δt = 20ms. It is found that the He is removed from the discharge in an e-folding time of about half a second for neutral beam heated plasmas and in an e-folding time of about 1.5 s in an OH plasma. The exhaust efficiency of helium amounts to about 8% and is close to the one for deuterium. The fuelling efficiency for the injected helium is found to be in the range of 50–100%; the remaining part seems to be stored in the TEXTOR walls. An estimate of the surface density leads to a value of several times 1013 cm−2. This helium can easily be liberated in succeeding discharges and can be removed efficiently when ALT is pumping.

Graphite tiles from both the ALT-II and inner-bumper limiters were removed from TEXTOR and subjected to materials analysis. Scanning-electron microscopy and energy dispersive X-ray analysis were performed at the Institut fur Reaktorwerkstoffe, Forschungszentrum Julich. Deuterium profiles and metallic contamination were examined using external ion beam analysis at Sandia National Laboratory-Albuquerque. The erosion and hydrogen recycling of the tiles, while subjected to plasma bombardment, were studied at University of California, Los Angeles. In-situ analysis of the inner-bumper limiter tiles was performed by Sandia National Laboratory-Livermore using beta backscattering. Results indicate low metallic impurity concentration on the surfaces of both types of tiles. Increased metallic concentration coincides with regions of increased plasma flux to the surface. The ALT-II tiles exhibit a uniformly eroded surface. The inner-bumper limiter tiles show both eroded and redeposited regions, in agreement with power deposition measurements to the tiles in TEXTOR. The redeposited regions show enhanced erosion and recycling when exposed to controlled plasma bombardment.

Recent topics on new materials for vacuum techniques mainly developed in Japan are overviewed with special emphasis on those which were motivated from the applications to nuclear fusion and accelerator researches, such as graphite, CC composites, ceramics, oxygen free copper and aluminum alloy vacuum components with honeycomb structure. High performance composite anode for X-ray tube, a good example of graphite and application of Chemical Vapour Deposition Technique, is also described.

In the current space development, space explorations are focused on by many space agencies in the world. Next lunar missions will be required to land on steep surface among rocks and craters. For the purpose of lunar soft-landing, dynamics analysis is necessaly especially in contact dynamics with regolith. This paper discusses landing simulation using Mechanical Dynamics Software ADAMS (product by MSC. Software Corp.). Simulation model is based on the lander in the SELENE-B project by Japan Aerospace Exploration Agency. The lander has four landing-gears, and total mass is 400-500kg. Two specific characteristics of simulation model are expressions for honey-comb-core in a landing-gear, and contact dynamics with regolith on the lunar surface. Simulation in this paper especially focuses on influences onsoft-lamding by lander orientation, slope angle, and friction force.