408 research outputs found
Carrier Relaxation Dynamics in the Organic Superconductor kappa-(BEDT-TTF)(2)Cu(NCS)(2) Under Pressure
Photo-induced carrier relaxation dynamics have been investigated for the organic superconductor kappa-(BEDT-TTF)(2)Cu(NCS)(2) with different probe polarization under 1.3 kbar at low temperatures. We successfully observed the isotropic and anisotropic responses for the probe polarization, which were found to appear at 56 K. By comparing the responses with and without applying pressure, we found that those were slightly changed, indicating that the application of pressure has effect on the carrier relaxation dynamics
Emergent Spontaneous Movements Based on Embodiment: Toward a General Principle for Early Development
We investigate whether spontaneous movements, which initiate and guide early development in animals, can be accounted for by the properties underlying embodiment. We constructed computer and robotic models of several biological species with biologically plausible musculoskeletal bodies and nervous systems, and extracted the embodied and motor networks based on inter-muscle connectivities. In computer simulations and robot experiments, we found that the embodied and motor networks had similar global and local topologies, suggesting the key role of embodiment in generating spontaneous movements in animals
Emergent Spontaneous Movements Based on Embodiment: Toward a General Principle for Early Development
We investigate whether spontaneous movements, which initiate and guide early development in animals, can be accounted for by the properties underlying embodiment. We constructed computer and robotic models of several biological species with biologically plausible musculoskeletal bodies and nervous systems, and extracted the embodied and motor networks based on inter-muscle connectivities. In computer simulations and robot experiments, we found that the embodied and motor networks had similar global and local topologies, suggesting the key role of embodiment in generating spontaneous movements in animals
The influence of size, specific gravity, and head position on the swallowing of solid preparations
AbstractAimTo clarify the influence of size and specific gravity of solid preparations, and the position of healthy volunteers when swallowing, for the purpose of practical use in patient consultation regarding the taking of medicines.Materials and methodsThe paper reports three studies. Volunteers were asked to swallow four different capsules (A, large and heavy; B, large and light; C, small and heavy; D, small and light) in Study 1, two preparations with different positions (upright, horizontal, and chin-down) in Study 2, and two preparations before and after anesthetization of the bilateral lingual and inferior alveolar nerve in Study 3. The oral transit time (OTT) and pharyngeal transit time (PTT) were evaluated with videofluoroscopy.ResultsThe mean OTT became longer in the order of C, D, B, A. The mean PTT showed no statistically significant differences. The swallowing preference of the four preparations ranked by the subjects showed that difference in size but not the difference in specific gravity is a significant factor. In the chin-down position, OTT was shorter for two preparations, compared with the other two positions. The mean OTT for both the A and B preparations was significantly longer after the bilateral lingual and inferior alveolar nerves were anesthetized.ConclusionWhen swallowing solid preparations, a consideration of size and the position will enable ease of swallowing of medicines. This would especially be the case when delivery of the medicines to be taken by the aged suffering from oral hypoesthesia caused by an underlying disease
Effects of astaxanthin on accommodation, critical flicker fusion, and pattern visual evoked potential in visual display terminal workers
We evaluated the effects of astaxanthin, a red carotenoid, on accommodation, critical flicker fusion (CFF), and pattern visual evoked potential (PVEP) in visual display terminal (VDT) workers. As controls, 13 non-VDT workers received no supplementation (Group A). Twenty-six VDT workers were randomized into 2 groups: Group B consisted of 13 subjects who received oral astaxanthin, 5 mg/day, for 4 weeks, and Group C consisted of 13 subjects who received an oral placebo, 5 mg/day, for 4 weeks. No significant difference in age was noted among the 3 groups. A double-masked study was designed in Groups B and C. Accommodation amplitude in Group A was 3.7± 1.5 diopters. Accommodation amplitudes (2.3±1.4 and 2.2±1.0 diopters) in Groups B and C before supplementation were significantly (p<0.05) lower than in Group A. Accommodation amplitude (2.8±1.6 diopters) in Group B after astaxanthin treatment was significantly (p<0.01) larger than before supplementation, while accommodation amplitude (2.3±1.1 diopters) in Group C after placebo supplementation was unchanged. The CFFs and amplitude and latency of P100 in PVEP in Group A were 45.0±4.2 Hz, 6.5±1.8μV, and 101.3±6.5 msec, respectively. The CFFs in Groups B and C before supplementation were significantly (p<0.05) lower than in Group A. The CCFs in Groups B and C did not change after supplementation. Amplitudes and latencies of P100 in PVEP in Groups B and C before supplementation were similar to those in Group A and did not change after supplementation. Findings of the present study indicated that accommodation amplitude improved after astaxanthin supplementation in VDT workers. 赤色カロチノイドの一種であるアスタキサンチンのvisual display terminal(VDT)作業者の調節力,中心フリッカー値,パターン視覚誘発電位に及ぼす影響を調べた。VDT作業を行わない13人をコントロールとした(Group A)。26人のVDT作業者を2群に無作為に分けた。Group Bはアスタキサンチン一日5mg 4週間内服した13人で,Group Cはアスタキサンチンを含有しないカプセルを4週間内服した13人とした。外見上同じカプセルでの内服投与を行った。結果:Group AはGroup B及びGroup Cと比較して,調節力,中心フリッカー値は有意に高い値であったが,パターン視覚誘発電位検査結果は,Group B,Cと有意差はなかった。Group Bでは,アスタキサンチンの投与前後で有意な調節力の改善がみられた(p<0.01)。しかし,中心フリッカー値,パターン視覚誘発電位に変化はみられなかった。Group Cでは,投与前後で,調節力,中心フリッカー値,パターン視覚誘発電位に変化はみられなかった。考察:VDT作業者では,非作業者と比べ調節力,中心フリッカー値が低下していることは以前より報告されており,今回の我々の研究でも同様の結果であった。VDT作業者で,アスタキサンチン非内服群では,調節力は投与前後で変化がなかったが,アスタキサンチンの内服群で,有意に調節力が改善した。VDT作業者の調節力の改善には,アスタキサンチンの内服が有効と考えられた
ヒト胎児シミュレーションを用いた発達における身体性寄与の構成論的解明
学位の種別: 課程博士審査委員会委員 : (主査)東京大学教授 國吉 康夫, 東京大学教授 多賀 厳太郎, 東京大学教授 神崎 亮平, 東京大学教授 廣瀬 通孝, 東京大学教授 中村 仁彦University of Tokyo(東京大学
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Artificial intelligence approaches to predicting and detecting cognitive decline in older adults: A conceptual review.
Preserving cognition and mental capacity is critical to aging with autonomy. Early detection of pathological cognitive decline facilitates the greatest impact of restorative or preventative treatments. Artificial Intelligence (AI) in healthcare is the use of computational algorithms that mimic human cognitive functions to analyze complex medical data. AI technologies like machine learning (ML) support the integration of biological, psychological, and social factors when approaching diagnosis, prognosis, and treatment of disease. This paper serves to acquaint clinicians and other stakeholders with the use, benefits, and limitations of AI for predicting, diagnosing, and classifying mild and major neurocognitive impairments, by providing a conceptual overview of this topic with emphasis on the features explored and AI techniques employed. We present studies that fell into six categories of features used for these purposes: (1) sociodemographics; (2) clinical and psychometric assessments; (3) neuroimaging and neurophysiology; (4) electronic health records and claims; (5) novel assessments (e.g., sensors for digital data); and (6) genomics/other omics. For each category we provide examples of AI approaches, including supervised and unsupervised ML, deep learning, and natural language processing. AI technology, still nascent in healthcare, has great potential to transform the way we diagnose and treat patients with neurocognitive disorders
Balance Measures Derived from Insole Sensor Differentiate Prodromal Dementia with Lewy Bodies
Dementia with Lewy bodies is the second most common type of neurodegenerative
dementia, and identification at the prodromal stagei.e., mild cognitive
impairment due to Lewy bodies (MCI-LB)is important for providing appropriate
care. However, MCI-LB is often underrecognized because of its diversity in
clinical manifestations and similarities with other conditions such as mild
cognitive impairment due to Alzheimer's disease (MCI-AD). In this study, we
propose a machine learning-based automatic pipeline that helps identify MCI-LB
by exploiting balance measures acquired with an insole sensor during a 30-s
standing task. An experiment with 98 participants (14 MCI-LB, 38 MCI-AD, 46
cognitively normal) showed that the resultant models could discriminate MCI-LB
from the other groups with up to 78.0% accuracy (AUC: 0.681), which was 6.8%
better than the accuracy of a reference model based on demographic and clinical
neuropsychological measures. Our findings may open up a new approach for timely
identification of MCI-LB, enabling better care for patients
Scalable parallel elastic–plastic finite element analysis using a quasi-Newton method with a balancing domain decomposition preconditioner
A domain decomposition method for large-scale elastic–plastic problems is proposed. The proposed method is based on a quasi-Newton method in conjunction with a balancing domain decomposition preconditioner. The use of a quasi-Newton method overcomes two problems associated with the conventional domain decomposition method based on the Newton–Raphson method: (1) avoidance of a double-loop iteration algorithm, which generally has large computational complexity, and (2) consideration of the local concentration of nonlinear deformation, which is observed in elastic–plastic problems with stress concentration. Moreover, the application of a balancing domain decomposition preconditioner ensures scalability. Using the conventional and proposed domain decomposition methods, several numerical tests, including weak scaling tests, were performed. The convergence performance of the proposed method is comparable to that of the conventional method. In particular, in elastic–plastic analysis, the proposed method exhibits better convergence performance than the conventional method
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