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We synthesized Poly(p-phenylene sulfonic acid-ran-2,5-benzophenone) (PPPS-BP) with high ion exchange capacity (IEC). This polymer formed a highly packed acid structure in the pores of porous thin substrates. In addition, the filled electrolyte polymer was cross-linked to obtain a practical membrane. In particular, the pores of the polyethylene microporous membrane were filled with cross-linked electrolytes with high IEC (5.1 meq g−1), derived from PPPS-BP, vinyl sulfonic acid, and triallyl isocyanurate. The membrane exhibited high proton conductivity and good single cell performance (H2/O2), equal to or higher than a commercial membrane (Nafion® HP) under a wide range of humidity conditions. The high proton conductivity appeared to be conferred by the highly packed acid structure in the membrane. The membrane also showed high mechanical durability in dry–wet cycle test. Therefore, the fabricated membrane presents as a good candidate for fuel cell applications under low relative humidity conditions.

SpaceWire is valuable because it facilitates the development of spacecraft subsystems such as payload instruments, mass memory, and onboard computers. On the other hand, it takes much time and effort for developers to configure an initiator of the SpaceWire network because they have to take account of the entire SpaceWire network in a spacecraft. As the target network becomes larger, the path addressing and the packet collision-free timeslot allocation are harder for the developers to configure. Furthermore, the configuration tables of the initiator should satisfy various constraints, such as the bandwidth limitation and priority of specific packets. These constraints are different in each spacecraft. In order that the developers can design the large-scale SpaceWire network efficiently, automatic configuration table generation under the constraints is indispensable. This paper presents a constraint-based configuration table generator (CTG) that automatically provides reliable redundant path routing and collision-free timeslot allocation for required transactions in the target topology. We apply a constraint solver to the CTG to set many kinds of user-defined constraints in the network. For example, the bandwidth limitation, priority of the packets, and other various constraints can be easily inputted into the CTG. The CTG automatically generates configuration tables satisfying these constraints. Additionally, the CTG reports network topology views with bandwidth utilization ratios. This helps developers to verify whether a generated configuration is just as designed. The CTG can also notify developers that their requirements cannot be solved. In this paper, we show the feasibility and effectiveness of this tool through evaluation using a large-scale SpaceWire network case.

The fluorescence properties of ion pair charge transfer (IPCT) complex with bithiophene group were studied by steady-state and time-resolved measurements in various solvents. The photophysical properties of 5,5′-di(4-pyridyl)-2,2′-bithiophene (DPBT) were identical to the unsubstituted bithiophene except for the peak wavelength. The absorption of polymeric 5,5′-di(4-pyridiniumyl)-2,2′-bithiophene (PBT2+) salts showed both the locally excited state (LE) and intramolecular charge transfer (ICT) bands in all solvents studied. In less-polar solvents such as cyclohexane and toluene, absorption spectra showed an IPCT band in addition to the LE and ICT bands. The fluorescence spectra of polymeric PBT2+ salts showed dual emission which originated from the LE and ICT states in polar solvents. The ICT fluorescence lifetime strongly depends on the solvent polarity. The fluorescence from the PBT2+ salts was effectively quenched by their counter ion in less-polar solvent. These results indicate that the counter halide anion affects on the excited-state relaxation process.

Viral vectors that can infect neurons transsynaptically and can strongly express foreign genes are useful for investigating the organization of neural circuits. We previously developed a propagation-competent rabies virus (RV) vector based on a highly attenuated HEP-Flury strain (rHEP5.0-CVSG), which selectively infects neurons and propagates between synaptically connected neurons in a retrograde direction. Its relatively low level of transgene expression, however, makes immunostaining necessary to visualize the morphological features of infected neurons. To increase the transgene expression level of this RV vector, in this study we focused on two viral proteins: the large protein (L) and matrix protein (M). We first attempted to enhance the expression of L, which is a viral RNA polymerase, by deleting the extra transcription unit and shortening the intergenic region between the G and L genes. This viral vector (rHEP5.0-GctL) showed increased transgene expression level with efficient transsynaptic transport. We next constructed an RV vector with a rearranged gene order (rHEP5.0-GML) with the aim to suppress the expression of M, which plays a regulatory role in virus RNA synthesis. Although this vector showed high transgene expression level, the efficiency of transsynaptic transport was low. To further evaluate the usability of rHEP5.0-GctL as a transsynaptic tracer, we inserted a fluorescent timer as a transgene, which changes the color of its fluorescence from blue to red over time. This viral vector enabled us the differentiation of primary infected neurons from secondary infected neurons in terms of the fluorescence wavelength. We expect this propagation-competent RV vector to be useful for elucidating the complex organization of the central nervous system.

SpaceFibre protocol, which is developed by European Space Agency as a standard protocol to communicate between payloads in satellite network, adopts multi-lane technique to increase transfer rate by using multiple physical links. To realize high transfer rate in which the multi-lane technique is needed, e.g. 20Gbps, FPGAs or ASICs devices to process the SpaceFibre protocol needs to increase operating frequency or to extend processing data width at one clock cycle. The later way is generally adapted for giga bps class transfer system since the operating frequency of FPGAs and ASICs for space systems is relatively lower than these devices for commercial systems. It is important to consider a length of data to be processed when extending the processing data width at one clock cycle. In the SpaceFibre protocol, it is effective to design processing device with 32-bits data width, because the minimum unit of transmitting/receiving data width is 32-bits. For example, however, if the width of data bus is assumed to 64-bits, it is possible that frame boundaries between leading data frame and following data frame is appeared in the middle of data bus. In this case, two frames have to be processed at the same time and it causes increase of complexity for processing and increase of circuit size. To mitigate the complexity, we change the frame length to be aligned with the utilized lane number at the framing layer. In this paper, we report the method for alignment of frame length and its evaluation results.

In this paper we present a trial of development of handheld AR supporting two interaction techniques based on the understanding that both real and virtual objects should be compatible in manipulation. One is the ability to contact virtual objects by user’s finger, as well as to physical objects in the real world. The virtual objects change their position, shape, and/or other graphical features according to his/her manipulation. The other technique we discuss in the paper concerns pseudo manipulation of virtual objects. The motion such as shake and tilt to a handheld device causes a certain effect to the virtual objects in the AR content.

A new polymer and small molecules containing the chromophore bis(2-(4-pyridiniumyl)thiazole) were synthesized. Their tetraphenylborate salts showed absorption spectral changes in the visible to near-infrared region accompanying a colour change from yellow to green on steady photoirradiation. From electron spin resonance measurements and comparison with Molecular Orbital PACkage (MOPAC) calculations, this was assigned to the formation of bis(2-(4-pyridiniumyl)thiazole) radicals due to a photoinduced electron-transfer reaction from tetraphenylborate and decomposition of its oxidized form. Transient absorption spectra corresponding to those of tetraphenylborate salts were observed for bromide salts on femtosecond laser excitation of the polymer in solid films and solutions. The fastest decay of transient absorption due to back electron transfer was less than 1 picosecond.