Growing Neural Gas with Different Topologies for 3D Space Perception

Three-dimensional space perception is one of the most important capabilities for an autonomous mobile robot in order to operate a task in an unknown environment adaptively since the autonomous robot needs to detect the target object and estimate the 3D pose of the target object for performing given tasks efficiently. After the 3D point cloud is measured by an RGB-D camera, the autonomous robot needs to reconstruct a structure from the 3D point cloud with color information according to the given tasks since the point cloud is unstructured data. For reconstructing the unstructured point cloud, growing neural gas (GNG) based methods have been utilized in many research studies since GNG can learn the data distribution of the point cloud appropriately. However, the conventional GNG based methods have unsolved problems about the scalability and multi-viewpoint clustering. In this paper, therefore, we propose growing neural gas with different topologies (GNG-DT) as a new topological structure learning method for solving the problems. GNG-DT has multiple topologies of each property, while the conventional GNG method has a single topology of the input vector. In addition, the distance measurement in the winner node selection uses only the position information for preserving the environmental space of the point cloud. Next, we show several experimental results of the proposed method using simulation and RGB-D datasets measured by Kinect. In these experiments, we verified that our proposed method almost outperforms the other methods from the viewpoint of the quantization and clustering errors. Finally, we summarize our proposed method and discuss the future direction on this research

Casein kinase 1γ acts as a molecular switch for cell polarization through phosphorylation of the polarity factor Tea1 in fission yeast

Fission yeast undergoes growth polarity transition from monopolar to bipolar during G2 phase, designated NETO (New End Take Off). It is known that NETO onset involves two prerequisites, the completion of DNA replication and attainment of a certain cell size. However, the molecular mechanism remains unexplored. Here, we show that casein kinase 1γ, Cki3 is a critical determinant of NETO onset. Not only did cki3∆ cells undergo NETO during G1‐ or S‐phase, but they also displayed premature NETO under unperturbed conditions with a smaller cell size, leading to cell integrity defects. Cki3 interacted with the polarity factor Tea1, of which phosphorylation was dependent on Cki3 kinase activity. GFP nanotrap of Tea1 by Cki3 led to Tea1 hyperphosphorylation with monopolar growth, whereas the same entrapment by kinase‐dead Cki3 resulted in converse bipolar growth. Intriguingly, the Tea1 interactor Tea4 was dissociated from Tea1 by Cki3 entrapment. Mass spectrometry identified four phosphoserine residues within Tea1 that were hypophosphorylated in cki3∆ cells. Phosphomimetic Tea1 mutants showed compromised binding to Tea4 and NETO defects, indicating that these serine residues are critical for protein–protein interaction and NETO onset. Our findings provide significant insight into the mechanism by which cell polarization is regulated in a spatiotemporal manner.T.K. was the recipient of a JSPS fellowship (PD) and was partly supported by ‘Strategic Young Researcher Overseas Visits Program for Accelerating Brain Circulation’ from JSPS. This work was supported by Cancer Research UK (T.T. and A.P.S) and the Ministry of Education, Culture, Sports, Science and Technology (D.H.)

Detection of muscle fatigue by the surface electromyogram and its application

金沢大学理工研究域電子情報学系金沢大学理工研究域電子情報学系The muscle is moved by muscle fiber contraction receiving command from the brain. But, energy that moves muscle is not infinity. If muscle get into energy shortage, no matter how send command from the brain, muscle is not moved. Such a temporary muscular dysfunction is muscle fatigue. If muscle becomes excess fatigue condition, it may decrease work efficiency, or muscle strain. If we are able to measure muscle fatigue objectively, improve work efficiency, or avert muscle strain. Therefore, it is necessity to measure muscle fatigue. It is able to objectively measure with a surface electromyogram(EMG). The feature of muscle fatigue are increase in amplitude and make the transition from high frequency spectrum to low frequency spectrum. We evaluate muscle fatigue Mean Power Frequency (MPF). to evaluates frequency of surface EMG.We assume muscle recovery process is converse phenomenon from muscle fatigue, and it is able to evaluate elevated MPF. The purpose of the present study is to design of system that effective training, or improve work efficiency, or avert muscle strain uses feature of muscular fatigue and muscle recovery process. © 2010 IEEE

Connective tissue growth factor is correlated with peritoneal lymphangiogenesis.

Lymphatic absorption in the peritoneal cavity may contribute to ultrafiltration failure in peritoneal dialysis (PD). Lymphatic vessels develop during PD-related peritoneal fibrosis. Connective tissue growth factor (CTGF, also called CCN2) is an important determinant of fibrotic tissue remodeling, but little is known about its possible involvement in lymphangiogenesis. In this study, we investigated the relationship between CTGF and peritoneal lymphangiogenesis. A positive correlation was observed between vascular endothelial growth factor-C (VEGF-C), a major lymphangiogenic growth factor, and the CTGF concentration in human PD effluents. CTGF expression was positively correlated with expression of lymphatic markers and VEGF-C in human peritoneal biopsies. We found a positive correlation between the increase in CTGF and the increase in VEGF-C in cultured human peritoneal mesothelial cells (HPMCs) treated with transforming growth factor-β1 (TGF-β1). The diaphragm is a central player in peritoneal lymphatic absorption. CTGF expression was also correlated with expression of VEGF-C and lymphatics in a rat diaphragmatic fibrosis model induced by chlorhexidine gluconate (CG). Furthermore, CTGF gene deletion reduced VEGF-C expression and peritoneal lymphangiogenesis in the mouse CG model. Inhibition of CTGF also reduced VEGF-C upregulation in HPMCs treated with TGF-β1. Our results suggest a close relationship between CTGF and PD-associated lymphangiogenesis

Dynamical aspects of quantum entanglement for weakly coupled kicked tops

We investigate how the dynamical production of quantum entanglement for weakly coupled, composite quantum systems is influenced by the chaotic dynamics of the corresponding classical system, using coupled kicked tops. The linear entropy for the subsystem (a kicked top) is employed as a measure of entanglement. A perturbative formula for the entanglement production rate is derived. The formula contains a correlation function that can be evaluated only from the information of uncoupled tops. Using this expression and the assumption that the correlation function decays exponentially which is plausible for chaotic tops, it is shown that {\it the increment of the strength of chaos does not enhance the production rate of entanglement} when the coupling is weak enough and the subsystems (kicked tops) are strongly chaotic. The result is confirmed by numerical experiments. The perturbative approach is also applied to a weakly chaotic region, where tori and chaotic sea coexist in the corresponding classical phase space, to reexamine a recent numerical study that suggests an intimate relationship between the linear stability of the corresponding classical trajectory and the entanglement production rate.Comment: 16 pages, 11 figures, submitted to Phys. Rev.

アートの記録・再現としての「アートブック」における活字・文字組版表現の研究

現代アートの表現手法は多様であり、その記録のための「アートブック」も様々な形式がある。また近年、アートの世界では言語表現･文字記号表現を含むものの重要性が増している。したがって従来の画像類の掲載・再現ではすまない記録法が求められている。本研究では考察されることの稀だった文字･組版表現とアートの記録について検証を行う。事例として2008年10月29日、ビジュアルデザイン学科による独自開催特別講義「Art ／内藤礼」を取り上げる。その繊細を極めた表現で国際的に活躍している美術科・内藤礼氏は、また寡黙な作家としても知られている。この特別講義は、自らの作品を語ることにきわめて稀な作家自身の言葉の貴重な記録となった。そうした内藤氏の表現の内実に対応した「本」をつくりあげることが本研究の課題であった。2009年12月、それは単行本「内藤礼〈母型〉」として刊行された。戸田ツトム教授の全面デザインによるこの単行本化の作業は、そうした高度なデザイン課題への挑戦でもあり、また現代デザインの隘路たる「デザインの消滅を企図するデザイン」への回答とも位置づけられるものとなった。作家の言葉の背後に広がる深い世界をいかに組版と図版により読者に伝えうるかという、デザインの試行である。As means of expression in contemporary art are diversied, art books as a medium for recording art also take many different styles. On the other hand, linguistic and character expressions have recently become increasingly important in the art scene.In this context, there should be a new means of recording art that goes beyond the simple presentation of graphic images in the conventional art books. This course studied typographic and compositional expression in art books as a medium for recording art.The course focused on exploring “Art / Rei Naito,” a special lecture presented by Department of Visual Design on October 29, 2008.Rei Naito is an artist whose refined sensitivity is highly reputed in the world. She is also renowned for being taciturn about her work. The lecture was a very rare opportunity in which the artist talked about her art. The purpose of this course was to make a “book” that reflects the essence of her artistic expression.The book, Naito Rei ＜Bokei＞, was published in December 2009. Designed entirely by Professor Tsutomu Toda, the whole process of making this book was a challenge to an advanced design issue as well as an answer to the “design intended to vanish design,” an aporia in contemporary design