221 research outputs found

    Application of Partitioned Iterative Coupling Approach to Multi-physics

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     The engineering needs which have to consider the multi-physics are increasing. When the multi-phase problem is treated by monolithic coupling approach, there are some difficulties such as the increase in the number of degree of freedom, the complication of the program code and so on. In order to overcome these shortcomings in considering the new additional phase, we applied the partitioned iterative coupling approach to the Hydro-Mechanical coupled problem in this research. In the partitioned iterative coupling approach, the behavior of single phases can be individually calculated and the interaction between the phases has been considered at an appropriate timing by the middleware. The middleware plays a role to regulate the single-phase analysis. In this research, we carried out the numerical simulation of one-dimensional consolidation by both the partitioned iterative coupling scheme and the monolithic coupling scheme, and then we confirmed that the numerical results are the same. Through the research, it figured out the efficient iterative scheme

    Computational model of recurrent subthalamo-pallidal circuit for generation of parkinsonian oscillations

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    Parkinson’s disease is a movement disorder caused by dopamine depletion in the basal ganglia. Abnormally synchronized neuronal oscillations between 8 Hz and 15 Hz in the basal ganglia are implicated in motor symptoms of Parkinson’s disease. However, how these abnormal oscillations are generated and maintained in the dopamine-depleted state is unknown. Based on neural recordings in a primate model of Parkinson’s disease and other experimental and computational evidence, we hypothesized that the recurrent circuit between the subthalamic nucleus (STN) and the external segment of the globus pallidus (GPe) generates and maintains parkinsonian oscillations, and that the cortical excitatory input to the STN amplifies them. To investigate this hypothesis through computer simulations, we developed a spiking neuron model of the STN-GPe circuit by incorporating electrophysiological properties of neurons and synapses. A systematic parameter search by computer simulation identified regions in the space of the intrinsic excitability of GPe neurons and synaptic strength from the GPe to the STN that reproduce normal and parkinsonian states. In the parkinsonian state, reduced firing of GPe neurons and increased GPe-STN inhibition trigger burst activities of STN neurons with strong post-inhibitory rebound excitation, which is usually subject to short-term depression. STN neuronal bursts are shaped into the 8-15-Hz, synchronous oscillations via recurrent interactions of STN and GPe neurons. Furthermore, we show that cortical excitatory input to the STN can amplify or suppress pathological STN oscillations depending on their phase and strength, predicting conditions of cortical inputs to the STN for suppressing oscillations

    Diel vertical migration of zooplankton off Adélie Land (East Antarctica) during austral summer, 2010, inferred from echograms

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    第2回極域科学シンポジウム/第33回極域生物シンポジウム 11月17日(木) 統計数理研究所 3階リフレッシュフロ

    Development and validation of a new scoring system for prognostic prediction of community-acquired pneumonia in older adults

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    The discriminative power of CURB-65 for mortality in community-acquired pneumonia (CAP) is suspected to decrease with age. However, a useful prognostic prediction model for older patients with CAP has not been established. This study aimed to develop and validate a new scoring system for predicting mortality in older patients with CAP. We recruited two prospective cohorts including patients aged ≥ 65 years and hospitalized with CAP. In the derivation (n = 872) and validation cohorts (n = 1, 158), the average age was 82.0 and 80.6 years and the 30-day mortality rate was 7.6% (n = 66) and 7.4% (n = 86), respectively. A new scoring system was developed based on factors associated with 30-day mortality, identified by multivariate analysis in the derivation cohort. This scoring system named CHUBA comprised five variables: confusion, hypoxemia (SpO2 ≤ 90% or PaO2 ≤ 60 mmHg), blood urea nitrogen ≥ 30 mg/dL, bedridden state, and serum albumin level ≤ 3.0 g/dL. With regard to 30-day mortality, the area under the receiver operating characteristic curve for CURB-65 and CHUBA was 0.672 (95% confidence interval, 0.607–0.732) and 0.809 (95% confidence interval, 0.751–0.856; P < 0.001), respectively. The effectiveness of CHUBA was statistically confirmed in the external validation cohort. In conclusion, a simpler novel scoring system, CHUBA, was established for predicting mortality in older patients with CAP

    A Case of Granulocyte-Colony Stimulating Factor-Producing Hepatocellular Carcinoma Confirmed by Immunohistochemistry

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    Granulocyte-colony stimulating factor (G-CSF) is a naturally occurring glycoprotein that stimulates the proliferation and maturation of precursor cells in the bone marrow into fully differentiated neutrophils. Several reports of G-CSF-producing malignant tumors have been published, but scarcely any in the hepatobiliary system, such as in hepatocellular carcinoma (HCC). Here, we encountered a 69-yr-old man with a hepatic tumor who had received right hepatic resection. He showed leukocytosis of 25,450/µL along with elevated serum G-CSF. Histological examination of surgical samples demonstrated immunohistochemical staining for G-CSF, but not for G-CSF receptor. The patient survived without recurrence for four years, but ultimately passed away with multiple bone metastases. In light of the above, clinicians may consider G-CSF-producing HCC when encountering patients with leukocytosis and a hepatic tumor. More cases are needed to clarify the clinical picture of G-CSF-producing HCC
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