59 research outputs found

    Vibration problem of a spherical tank containing jet propellant: numerical simulations

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    This document is the final report on the joint research project on vibration problem of a spherical tank containing jet propellant between IHI, Japan and SES, University of Southampton, UK. The background of the project is described. The fundamental principles and numerical method used in numerical simulations are presented. The detailed FEA models for each studied cases are given. The calculation results are presented using tables, curves, figures as well as the attached data files. The available experiment results are listed to compare with the numerical calculations. The calculation results show a fundamental agreement with the experiment results. The numerical analysis confirms that:1)Due to water – tank interaction, the natural frequencies of the water – tank system are decreased with the water level increase. For the 25% water level, the natural frequencies, especially heave mode frequency, shows a significant decrease compared with the empty case. However, with continuing increase the filed water more than 25% level, the decrease gradient of the natural frequencies gradually tends to zero. In the 100% water case, the natural frequency of heave mode is about 200 Hz which can not equal zero.2)Considering free surface wave effect produces a lot of sloshing modes of very low frequencies compared with the natural frequencies of the dry tank structure. Therefore, for dynamic response analysis with high frequency excitations, the free surface wave may be neglected. However, to assess loads caused by sloshing modes, the free surface waves have to be considered.3)There exist relative big deformations at the four tank support places in several vibration modes, which may produce a large local stress at support places to cause the product fail in vibration environment. A strengthen local design at the support places is needed.4)The dynamic response results are affected by damping coefficients of all modes used in the dynamic response analysis. The damping coefficients are approximately presented and therefore, the numerical results are good reference for practical designs.The report confirms that the original purpose of this joint research project has well completed by IHI and SES

    Multi-Dimensional Memory Frames and Action Generation in the MHP/RT Cognitive Architecture

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    AbstractThe main theme of this paper is to provide a cognitive architecture, MHP/RT (Model Human Processor with Realtime Constraints), that is appropriate for describing the idea, “The agent would not be getting an informational input or a reinforcement, but the inputs would be better described as perturbations on a self-organizing complex systems”, as stated in the call for the workshop, Enaction, Complex Systems and Cognitive Architectures. MHP/RT describes a cyclic process of action selection and memorization while one lives in the world, and the memory is gradually structured as multi-dimensional frames as one interacts with the environment. Behavioral processing constraints are imposed by conscious and unconscious processes, and behavior must be synchronized with the ever-changing external and internal environments. This paper provides a brief explanation of MHP/RT and multi-dimensional memory frames, followed by how memory is structured as one develops

    Gravity sensing in plant and animal cells

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    Gravity determines shape of body tissue and affects the functions of life, both in plants and animals. The cellular response to gravity is an active process of mechanotransduction. Although plants and animals share some common mechanisms of gravity sensing in spite of their distant phylogenetic origin, each species has its own mechanism to sense and respond to gravity. In this review, we discuss current understanding regarding the mechanisms of cellular gravity sensing in plants and animals. Understanding gravisensing also contributes to life on Earth, e.g., understanding osteoporosis and muscle atrophy. Furthermore, in the current age of Mars exploration, understanding cellular responses to gravity will form the foundation of living in space

    The relation between subjective symptom and circulation during orthostatic stress using a tilt table

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    起立負荷時における気分不良の有無と体循環,脳循環との関係について検討することを目的とし,電動チルト台を用いて起立負荷を行った.対象者は20代の自律神経疾患を有さない健常女性12名とし,起立負荷によって気分不良を示さなかった群を正常群とし,示した群を気分不良群とした.電動tilt tableを0°→ 30°→ 45°→ 60°→ 0°と変化させ,各段階を約3分ずつ保持した.その際,平均動脈血圧(MBP),心拍出量,心拍数,1回拍出量,総末梢血管抵抗,腓腹筋内側頭部のTotal Hb,中大脳動脈の平均血流速度(FV)と末梢血管抵抗(PI)を測定し,気分不良尺度を10段階評価でもって記録した.その結果,正常群は起立負荷に伴いFVは低下を示したが,MBP,PIに著変はなく,気分不良群はMBPの上昇に対してPIは減少し,FVはほぼ変化はみられなかった.一般的にめまいなどの気分不良症状は脳血流量の減少により生じるとされていたが,今回の結果では気分不良には脳血流量の増加による脳細動脈へのストレスなどが考えられた.This study aimed at considering the relation between subjective symptoms and the circulation of healthy women during orthostatic stress using a tilt table. From 12 healthy women in there twenties who don't have autonomic nervous disorders, two groups were formed: 1) a normal group which didn't feel ill during orthostatic stress, and 2) a FI group which feel ill during orthostatic stress. An electric tilt table was changed from 0°→30°→45°→60°→0°, and each stage was held for about 3 minutes. Mean artery blood pressure (MBP), cardiac output, heart rate, stroke volume, total peripheral resistance and total hemoglobin at the part of interior gastrocnemius (Total Hb), flow velocity (FV) and peripheral resistance (PI) of the middle cerebral artery (MCA) were measured. The scale of poor feeling was also recorded by10 stage evaluations. Consequently, although the normal group showed an FV fall with orthostatic stress,there were no significant changes in MBP and PI. In the FI group, PI decreased but FV didn't show muchchange with the rise of MBP. According to this result, the stress to the arteriola caused not by a fall but anincrease in the cerebral blood flows etc. seems thus to have been the source of the feeling

    Decreased serum pyridoxal levels in schizophrenia : meta-analysis and Mendelian randomization analysis

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    Background: Alterations in one-carbon metabolism have been associated with schizophrenia, and vitamin B6 is one of the key components in this pathway. Methods: We first conducted a case–control study of serum pyridoxal levels and schizophrenia in a large Japanese cohort (n = 1276). Subsequently, we conducted a meta-analysis of association studies (n = 2125). Second, we investigated whether rs4654748, which was identified in a genome-wide association study as a vitamin B6-related single nucleotide polymorphism, was genetically implicated in patients with schizophrenia in the Japanese population (n = 10 689). Finally, we assessed the effect of serum pyridoxal levels on schizophrenia risk using a Mendelian randomization (MR) approach. Results: Serum pyridoxal levels were significantly lower in patients with schizophrenia than in controls, not only in our cohort, but also in the pooled data set of the meta-analysis of association studies (standardized mean difference –0.48, 95% confidence interval [CI] –0.57 to –0.39, p = 9.8 × 10–24). We failed to find a significant association between rs4654748 and schizophrenia. Furthermore, an MR analysis failed to find a causal relationship between pyridoxal levels and schizophrenia risk (odds ratio 0.99, 95% CI 0.65–1.51, p = 0.96). Limitations: Food consumption and medications may have affected serum pyridoxal levels in our cross-sectional study. Sample size, number of instrumental variables and substantial heterogeneity among patients with schizophrenia are limitations of an MR analysis. Conclusion: We found decreased serum pyridoxal levels in patients with schizophrenia in this observational study. However, we failed to obtain data supporting a causal relationship between pyridoxal levels and schizophrenia risk using the MR approach

    トクシマシ イシカイ ガ ウンエイ スル トクシマシ チイキ ホウカツ シエン センター ノ トリクミ

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    The Tokushima City Integrated Community Care Support Center, a public institution responsible for the Long-Term Care Insurance and welfare administration of Tokushima City, has high business operations fair and neutrality. The only support center in Tokushima City has been entrusted to the Tokushima City Medical Association and is a large center unusual in Japan. We are working to cooperation with relevant organizations to support the medical and health, welfare and care of the community. We try to establish an Integrated Community Care system, as elderly can continue to live so long and dignified. We divided a daily living area of Tokushima City into four, and have placed the staff for each area. The current number of staff is 54 people in total, including public health nurses, social workers, chief care managers, and so on. Number of consultations reaches 36,000 per year. Occasionally, we received over 160 consultations a day. There are a wide variety of consultation contents such as Dementia and long-term care services, elder abuse and consumer damage. Because of Medical Association’s operation, we are able to easily construct cooperation with the healthcare and the long-time care system. Therefore, the all citizens of Tokushima City can receive standard services equally, fair, and neutrally. There is no regional disparity, there is no user of the enclosure. Because we have14branches of the support center in the city, they can bring a high level convenience to the citizens. It seems necessary to focus on the development of four promotions for the future citizens, ① Enhancement of the center output ② Cooperation of the healthcare and the long-term care ③ Improvement of the area community care conference ④ Increase of measures against Dementia

    CNVs in Three Psychiatric Disorders

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    BACKGROUND: We aimed to determine the similarities and differences in the roles of genic and regulatory copy number variations (CNVs) in bipolar disorder (BD), schizophrenia (SCZ), and autism spectrum disorder (ASD). METHODS: Based on high-resolution CNV data from 8708 Japanese samples, we performed to our knowledge the largest cross-disorder analysis of genic and regulatory CNVs in BD, SCZ, and ASD. RESULTS: In genic CNVs, we found an increased burden of smaller (500 kb) exonic CNVs in SCZ/ASD. Pathogenic CNVs linked to neurodevelopmental disorders were significantly associated with the risk for each disorder, but BD and SCZ/ASD differed in terms of the effect size (smaller in BD) and subtype distribution of CNVs linked to neurodevelopmental disorders. We identified 3 synaptic genes (DLG2, PCDH15, and ASTN2) as risk factors for BD. Whereas gene set analysis showed that BD-associated pathways were restricted to chromatin biology, SCZ and ASD involved more extensive and similar pathways. Nevertheless, a correlation analysis of gene set results indicated weak but significant pathway similarities between BD and SCZ or ASD (r = 0.25–0.31). In SCZ and ASD, but not BD, CNVs were significantly enriched in enhancers and promoters in brain tissue. CONCLUSIONS: BD and SCZ/ASD differ in terms of CNV burden, characteristics of CNVs linked to neurodevelopmental disorders, and regulatory CNVs. On the other hand, they have shared molecular mechanisms, including chromatin biology. The BD risk genes identified here could provide insight into the pathogenesis of BD
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