Pre-Flight Testing Results of Multiple Water Propulsion Systems - Resistojet and Ion Thruster for SmallSats

This paper described re-flight flight testing results of the miniature water propulsion system combined an ion thruster and resistojet thrusters which is to be demonstrated on-orbit by JAXA’s program named Innovative Satellite Technology Demonstration-3. The unified propulsion system has a huge potential to expand micro/nano-spacecraft utilization and decrease the risk of debris

Multiple Water Propulsion Systems: All Propulsive Capabilities for CubeSats From LEO to Deep Space

The proposal is a multiple water propulsion system which combines a water resistojet and water ion thruster

Subunit rotation in a single FoF1-ATP synthase in a living bacterium monitored by FRET

FoF1-ATP synthase is the ubiquitous membrane-bound enzyme in mitochondria, chloroplasts and bacteria which provides the 'chemical energy currency' adenosine triphosphate (ATP) for cellular processes. In Escherichia coli ATP synthesis is driven by a proton motive force (PMF) comprising a proton concentration difference {\Delta}pH plus an electric potential {\Delta}{\Psi} across the lipid membrane. Single-molecule in vitro experiments have confirmed that proton-driven subunit rotation within FoF1-ATP synthase is associated with ATP synthesis. Based on intramolecular distance measurements by single-molecule fluorescence resonance energy transfer (FRET) the kinetics of subunit rotation and the step sizes of the different rotor parts have been unraveled. However, these experiments were accomplished in the presence of a PMF consisting of a maximum {\Delta}pH ~ 4 and an unknown {\Delta}{\Psi}. In contrast, in living bacteria the maximum {\Delta}pH across the plasma membrane is likely 0.75, and {\Delta}{\Psi} has been measured between -80 and -140 mV. Thus the problem of in vivo catalytic turnover rates, or the in vivo rotational speed in single FoF1-ATP synthases, respectively, has to be solved. In addition, the absolute number of functional enzymes in a single bacterium required to maintain the high ATP levels has to be determined. We report our progress of measuring subunit rotation in single FoF1-ATP synthases in vitro and in vivo, which was enabled by a new labeling approach for single-molecule FRET measurements.Comment: 9 pages, 6 figure

On-Orbit Demonstration of the Water Resistojet Propulsion System on Commercial 6U-Sat SPHERE-1 EYE

SPHERE-1 EYE, a 6U CubeSat developed by Sony Group Corporation, was launched at the beginning of 2023. The satellite included a water resistojet propulsion system, which is designed for orbit raising after the initial checkout. The water resistojet propulsion system consists of a tank, a vaporizer, nozzles, a control board, and a power processing unit. The form factor of the propulsion system is 1.25 U, the wet mass is 1.4 kg, and the achievable total impulse of the system is 170 Ns or higher. A unique design of the water propulsion system is a vaporization chamber generating steam at room temperature and low pressure, under 10 kPa. The performance measured on the ground shows a thrust of 2.7 mN, and a specific impulse of 60 s. A qualification test campaign including vibration, shock, thermal, throughput, and system performance tests was conducted, followed by acceptance tests. On-orbit demonstration was conducted on March 3rd and 16th for all four nozzles and the thrust generation was confirmed. The estimated thrust on orbit was 6.1 - 7.2 mN. Comparison between the on-orbit results and the ground tests demonstrated the functionality of the system as anticipated

Generation and Evaluation of Concept Embeddings Via Fine-Tuning Using Automatically Tagged Corpus

Ibaraki UniversityNational Institute for Japanese Language and LinguisticsIbaraki Universit

Follistatin-like 5 is expressed in restricted areas of the adult mouse brain: Implications for its function in the olfactory system

Follistatin‐like 5 (Fstl5), a member of the follistatin family of genes, encodes a secretory glycoprotein. Previous studies revealed that other members of this family including Fstl1 and Fstl3 play an essential role in development, homeostasis, and congenital disorders. However, the in vivo function of Fstl5 is poorly understood. To gain insight into the function of Fstl5 in the mouse central nervous system, we examined the Fstl5 expression pattern in the adult mouse brain. The results of in situ hybridization analysis showed a highly restricted pattern of Fstl5, namely, with localization in the olfactory system, hippocampal CA3 area and granular cell layer of the cerebellum. Restricted expression in the olfactory system suggests a possible role for Fstl5 in maintaining odor perception

All-words WSDとfine-tuningを利用した分類語彙表の語義の分散表現の構築

Ibaraki UniversityIbaraki UniversityIbaraki University会議名: 言語資源活用ワークショップ2019, 開催地: 国立国語研究所, 会期: 2019年9月2日−4日, 主催: 国立国語研究所 コーパス開発センター近年、単語を低次元の実数値ベクトルで表した分散表現が自然言語処理の様々な分野で利用されている。さらに、単語の分散表現や、その作成手法の応用により語義ごとの分散表現を作成する研究がされており多くのタスクで有効な結果を残している。しかし、一般に人手で語義が付与されたコーパスは量が少ないため、十分な量の語義が付与されたコーパスの確保は困難である。そこで、本稿では、語義を自動的に付与した大量の精度が低いコーパスから、作成した分散表現をもとに、人手で語義が付与された少量の精度が高いコーパスを用いてfine-tuningを行い、分類語彙表の語義の分散表現を作成し、その精度を検証した。その結果、分散表現の距離を用いた順位付けによる評価により、fine-tuningによる精度の向上が認められた

Attractive and permissive activities of semaphorin 5A toward dorsal root ganglion axons in higher vertebrate embryos

Elongation of the efferent fibers of dorsal root ganglion (DRG) neurons toward their peripheral targets occurs during development. Attractive or permissive systems may be involved in this elongation. However, the molecular mechanisms that control it are largely unknown. Here we show that class 5 semaphorin Sema5A had attractive/permissive effects on DRG axons. In mouse embryos, Sema5A was expressed in and around the path of DRG efferent fibers, and cell aggregates secreting Sema5A attracted DRG axons in vitro. We also found that ectopic Sema5A expression in the spinal cord attracted DRG axons. Together, these findings suggest that Sema5A functions as an attractant to elongate DRG fibers and contributes to the formation of the early sensory network

A three-component model of the spinal nerve ramification: Bringing together the human gross anatomy and modern Embryology

Due to its long history, the study of human gross anatomy has not adequately incorporated modern embryological findings; consequently, the current understanding has often been incompatible with recent discoveries from molecular studies. Notably, the traditional epaxial and hypaxial muscle distinction, and their corresponding innervation by the dorsal and ventral rami of the spinal nerve, do not correspond to the primaxial and abaxial muscle distinction, defined by the mesodermal lineages of target tissues. To resolve the disagreement between adult anatomy and embryology, we here propose a novel hypothetical model of spinal nerve ramification. Our model is based on the previously unknown developmental process of the intercostal nerves. Observations of these nerves in the mouse embryos revealed that the intercostal nerves initially had superficial and deep ventral branches, which is contrary to the general perception of a single ventral branch. The initial dual innervation pattern later changes into an adult-like single branch pattern following the retraction of the superficial branch. The modified intercostal nerves consist of the canonical ventral branches and novel branches that run on the muscular surface of the thorax, which sprout from the lateral cutaneous branches. We formulated the embryonic branching pattern into the hypothetical ramification model of the human spinal nerve so that the branching pattern is compatible with the developmental context of the target muscles. In our model, every spinal nerve consists of three components: (1) segmental branches that innervate the primaxial muscles, including the dorsal rami, and short branches and long superficial anterior branches from the ventral rami; (2) plexus-forming intramural branches, the serial homolog of the canonical intercostal nerves, which innervate the abaxial portion of the body wall; and (3) plexus-forming extramural branches, the series of novel branches located outside of the body wall, which innervate the girdle and limb muscles. The selective elaboration or deletion of each component successfully explains the reasoning for the standard morphology and variability of the spinal nerve. Therefore, our model brings a novel understanding of spinal nerve development and valuable information for basic and clinical sciences regarding the diverse branching patterns of the spinal nerve

AQT-D: Demonstration of the Water Resistojet Propulsion System by the ISS-Deployed CubeSat

AQT-D (AQua Thruster-Demonstrator) is a 3U CubeSat for a demonstration of a water resistojet propulsion system developed by The University of Tokyo. AQT-D installed the 1U propulsion system using water as a propellant, named AQUARIUS-1U (AQUA ResIstojet propUlsion System 1U). We completed the design and assembly of the AQT-D flight model. AQUARIUS-1U was fired on a pendulum-type thrust balance, and its performance was directly characterized in both a stand-alone test and an integrated test using an entire spacecraft system. AQT-D is currently scheduled to be delivered to JAXA in July 2019 and launched to the International Space Station (ISS) in the middle of 2019 by the H-IIB rocket. AQT-D will be deployed from the Japanese Experiment Module (JEM), known as Kibo, and demonstrate water propulsion technology