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Additional file 1. Supplementary Figures S1–S45, Supplementary Tables S1 and S2.

In protein structures, the fold is described according to the spatial arrangement of secondary structure elements (SSEs: α-helices and β-strands) and their connectivity. The connectivity or the pattern of links among SSEs is one of the most important factors for understanding the variety of protein folds. In this study, we introduced the connectivity strings that encode the connectivities by using the types, positions, and connections of SSEs, and computationally enumerated all the connectivities of two-layer αβ sandwiches. The calculated connectivities were compared with those in natural proteins determined using MICAN, a nonsequential structure comparison method. For 2α-4β, among 23,000 of all connectivities, only 48 were free from irregular connectivities such as loop crossing. Of these, only 20 were found in natural proteins and the superfamilies were biased toward certain types of connectivities. A similar disproportional distribution was confirmed for most of other spatial arrangements of SSEs in the two-layer αβ sandwiches. We found two connectivity rules that explain the bias well: the abundances of interlayer connecting loops that bridge SSEs in the distinct layers; and nonlocal β-strand pairs, two spatially adjacent β-strands located at discontinuous positions in the amino acid sequence. A two-dimensional plot of these two properties indicated that the two connectivity rules are not independent, which may be interpreted as a rule for the cooperativity of proteins.

Carbon fiber reinforced shape memory polymer (FR-SMP) has been developed for space deployable structures as solar paddles, antennas, etc. This material is lightweight, low-cost, and has high workability. We have experimentally proved enough tolerance against space environment for its mechanical and shapes recover property. Deploying test using flat plate models has been revealed that unidirectional reinforced configuration has good shape memory property due to well-balanced rigidity and flexibility. Hemisphere model has been produced through newly-developed FR-SMP dry prepreg., 資料番号: AA0049500010, レポート番号: JAXA-SP-06-006

H-2A launch vehicle general review revealed reduction in strength of thermal insulator on the fairing. Sealant which adheres sheet insulator was found incurable also. Mechanical tests and SEM (Scanning Electron Microscope) observations suggested that incomplete mixing of the raw materials was the reason of lower strength due to degraded uniformity of the insulator. By improving mixing process, well performed, firm insulator was achieved. Evaluation of cure processes proved that alcohol released during insulator cure obstructed hardening of sealant resulting in insufficient cure time. Adequate cure time assured reduced alcohol release and mature vulcanization of sealant. The process was improved based on these findings, and this resulted in more reliable insulator., 資料番号: AA0049056023, レポート番号: JAXA-SP-05-010

On October 25, 2004 ADEOS-2 (Advanced Earth Observing Satellite-2; Midori-2) ceased supplying observational data owing to a catastrophic power failure. FTA (Fault Tree Analysis) suggested that a rupture or short circuit of the power harness between the PDL (Solar Array Paddle Subsystem) and the electric power subsystem was the most likely cause. Material tests were conducted on the harness to elucidate the failure mechanism. High-temperature thermal cycling was seen to lead to anomalous expansion and contraction of the harness cable insulators. This phenomenon resulted in abrasion and fatigue of these materials., 資料番号: AA0048468019, レポート番号: JAXA-SP-04-010

Since spacecraft structures constitute a high proportion of total satellite mass, sandwich panels are commonly used which consist of a honeycomb core and either a CFRP or aluminum skin. Sandwich panels have a high specific rigidity, but are expensive to manufacture. JAXA has developed light weight sandwich panels using integral molding of CFRP-prepreg and light weight plastic foam. This material has good workability, design flexibility and a low cost of manufacture. Research on the material's applicability to space structures is almost completed. In this paper, reported are the results of vibration testing of a 50-kg class satellite assembly using these light weight sandwich panels., 資料番号: AA0048057025, レポート番号: JAXA-RM-04-010

ADEOS-2 (Advanced Earth Observing Satellite-2) stopped supplying observation data due to reduction of electric power supply. FTA (Fault Tree Analysis) suggested that breakage or short circuit of the power supply harness between PDL (Solar Array Paddle Subsystem) and the electric power subsystem was the most possible cause. Each phase of the failure scenario was evaluated with tests and analyses. This paper reports evaluation of material degradation for the failure case verification., 資料番号: AA0048057019, レポート番号: JAXA-RM-04-010

The safety for manned space systems is fundamental technology that should be secured. The purpose of research on off-gas monitoring technique is to ensure and improve the safety of manned space systems by developing the off-gas monitoring techniques for quickly and precisely detecting both toxic gases and abnormally elevated temperatures in manned space systems. Fire safety is especially important when using materials and parts in manned space systems. The human safety considerations of various materials and parts, in terms of their flammability and fire safety in a micro G environment, will promote their improved design and use., 資料番号: AA0048129014, レポート番号: JAXA-RM-04-011

8th Japan International SAMPE Symposium(November 18-21,2003), 資料番号: ARDS030531000

第47回宇宙科学技術連合講演会(2003年11月17-19日, 新潟コンベンションセンター「朱鷺メッセ」), 資料番号: ARDS03040000, レポート番号: 2G2

第1回宇宙環境シンポジウム(2004年12月2- 3日, 筑波宇宙センター 総合開発推進棟1階 大会議室), つくば市, 茨城県, 資料番号: ARDS04248000

The 24th International Symposium on Space Technology and Science(24th ISTS) (May 30-June 6, 2004, World Convention Center "Summit", PHOENIX SEAGAIA), Miyazaki, Japan, 資料番号: ARDS04037000, レポート番号: ISTS 2004-o-1-02v