• Transactions of Materials Processing
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• v.30 no.4
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• pp.201-210
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• 2021

• Annals of Clinical Neurophysiology
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• v.14 no.2
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• pp.64-71
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• 2012

Background: It is generally accepted that upper motor neuron (UMN) lesion can alter lower motor neuron (LMN) function by the plasticity of neural circuit. However there have been only few researches regarding the axonal excitability of LMN after UMN injury especially during the acute stage. The aim of this study was to investigate the nerve excitability properties of the LMNs following an acute to subacute supratentorial corticospinal tract lesion. Methods: An automated nerve excitability test (NET) using the threshold tracking technique was utilized to measure multiple excitability indices in median motor axons of 15 stroke patients and 20 controls. Testing of both paretic and non-paretic side was repeated twice, during the acute stage and subacute stage. The protocols calculated the strength-duration time constant from the duration-charge curve, parameters of threshold electrotonus (TE), the current-threshold relationship from sequential sub-threshold current, and the recovery cycle from sequential supra-threshold stimulation. Results: On the paretic side, compared with the control group, significant decline of superexcitablity and increase in the relative refractory period were observed during the subacute stage of stroke. Additionally, despite the absence of statistical significance, a mildly collapsing in ('fanning in') of the TE was found. Conclusions: Our results suggest that supratentorial brain lesions can affect peripheral axonal excitability even during the early stage. The NET pattern probably suggests background membrane depolarization of LMNs. These features could be associated with trans-synaptic regulation of UMNs to LMNs as one of the "neural plasticity" mechanisms in acute brain injury.

• Annals of Rehabilitation Medicine
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• v.42 no.6
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• pp.777-787
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• 2018

Objective To examine the long-term effects of the low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) combined with task-specific training on paretic hand function following subacute stroke. Methods Sixteen participants were randomly selected and grouped into two: the experimental group (real LF-rTMS) and the control group (sham LF-rTMS). All the 16 participants were then taken through a 1-hour task-specific training of the paretic hand. The corticospinal excitability (motor evoke potential [MEP] amplitude) of the non-lesioned hemisphere, and the paretic hand performance (Wolf Motor Function Test total movement time [WMFT-TMT]) were evaluated at baseline, after the LF-rTMS, immediately after task-specific training, 1 and 2 weeks after the training. Results Groups comparisons showed a significant difference in the MEP after LF-rTMS and after the training. Compared to the baseline, the MEP of the experimental group significantly decreased after LF-rTMS and after the training and that effect was maintained for 2 weeks. Group comparisons showed significant difference in WMFT-TMT after the training. Only in the experimental group, the WMFT-TMT of the can lifting item significantly reduced compared to the baseline and the effect was sustained for 2 weeks. Conclusion The results of this study established that the improvement in paretic hand after task-specific training was enhanced by LF-rTMS and it persisted for at least 2 weeks.

• Transactions of Materials Processing
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• v.6 no.6
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• pp.482-488
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• 1997

New carbon equivalent equation for the better prediction for the better prediction of roll force in a continuous hot strip mill has been formulated by applying a neural network method. In predicting roll force of steel strip, carbon equivalent equation which normalize the effects of various alloying elements by a carbon equivalent content is very critical for the accurate prediction of roll force. To overcome the complex relationships between alloying elements and operational variables such as temperature, strain, strain rate and so forth, a neural network method which is effective for multi-variable analysis was adopted in the present work as a tool to determine a proper carbon equivalent equation. The application of newly formulated carbon equivalent equation has increased prediction accuracy of roll force significantly and the effectiveness of neural network method is well confirmed in this study.

• Transactions of Materials Processing
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• v.29 no.6
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• pp.338-346
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• 2020

A V-bending test was performed in order to predict springback of high-strength steel sheets under various conditions. The results of V-Bending test were analyzed with artificial neural networks and FE-simulation, respectively, for the tool design. The results of design are discussed. The bending test result using the tool designed with artificial neural networks was about 92˚. However, the bending test result using the tool designed FE-simulation was about 94.5˚. Artificial neural networks are a useful tool along with FE-simulation in predicting springback.

• The Korea Journal of Herbology
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• v.24 no.1
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• pp.179-189
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• 2009

Objectives : Coptidis Rhizoma (Coptis japonica MAKINO; CR) is a well known crude drug as antimicrobial, antibacterial, anti-inflammatory, antioxidant activity. However, there is no study of the effect of CR on brain infarction and it's mechanism. The aim of this study was to investigate the effects on ischemic stroke induced by photothrombotic infarction by evaluating the functional & neuronal recovery after brain infarction. Materials & Methods : Male Sprague-Dawley rats (250-300 g) were induced photothrombotic brain infarction on sensorimotor cortex, and brain infarction volume by image J software (NIH, USA) after Nissl stain, also single pellet reaching task as a functional motor recovery were observed. After orally pretreated by CR (500 mg/kg) or normal saline as a sham control before 7 days from the time of photothrombotic infarction, rats were sacrificed. After then we analysed anti-inflammatory cytokines (TNF-$\alpha$, IL-6, IL-1$\beta$), by RT-PCR and ELISA method, and immunohistochemistry (GFAP, connexin-43) as a marker of neural plasticity. Results : CR (100, 250, 500 mg/kg) decreased the infarction volume dose-dependently, however the effect of 500mg/kg of CR (CR 500) showed the best (P=0.051). Also, CR 500 decreased the infarction volume time-dependently, the most effective time was 3-7 days after stroke. Photothrombosis increased inflammatory cytokines after infarction, CR 500 suppressed significantly mRNA expression of IL-1$\beta$, IL-6 and TNF-$\alpha$. In serum, CR 500 decreased the amount of IL-1$\beta$, 12h, 24h and 48h respectively (p < 0.05), also decreased that of IL-6 and TNF-$\alpha$, 12h respectively (p < 0.05) after infarction. The more astrocytes were observed and neural plasticity was facilitated in the rat brain of CR 500 than that of sham control in immunohistochemistry. Conclusions : This results suggest that CR decrease infarction volume and improve functional motor recovery in acute stage in photothrombotic ischemic infarction model in the mechanism of anti-inflammation and promoting neural plasticity.

• Korean Journal of Biological Psychiatry
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• v.9 no.2
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• pp.79-94
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• 2002

Polarisation of biological and psychosocial aspects of psychiatry is nowadays main stream. Current knowledges of the interaction between biology and psychology make it possible to consider a truly integrative approach of the two aspects. Research findings suggest that the neuronal plasticity is the key mechanism to answer how the mental function work to an environmental stimuli and how the psychotherapeutic approach work on the brain. Advances in neuroscience research have led to a more sophisticated understanding of how psychotherapy may affect brain function. Even though there have been a tremendous efforts to find out the neurobiological mechanism of mental function, the answer is at best premature. In this article, research findings about of neuronal plasticity, implicit memory, animal studies which were associated with psychotherapy and psychological aspects were reviewed.

• Transactions of Materials Processing
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• v.9 no.6
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• pp.644-652
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• 2000

Tube hydroforming is recently drawing attention of automotive industries due to its several advantages over conventional methods. It can produce wide range of products such as subframes, engine cradles, and exhaust manifolds with cheaper production cost by reducing overall number of processes. h successful tube hydroforming depends on the reasonable combination of the internal pressure and axial load at the tube ends. This paper deals with the optimal process design of hydroforming process using the genetic algorithm and neural network. An optimization technique is used in order to minimize the tube thickness variation by determining the optimal loading path in the tube expansion forming and the tube T-shape forming process.

• BMB Reports
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• v.50 no.5
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• pp.237-246
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• 2017

Synapse is the basic structural and functional component for neural communication in the brain. The presynaptic terminal is the structural and functionally essential area that initiates communication and maintains the continuous functional neural information flow. It contains synaptic vesicles (SV) filled with neurotransmitters, an active zone for release, and numerous proteins for SV fusion and retrieval. The structural and functional synaptic plasticity is a representative characteristic; however, it is highly vulnerable to various pathological conditions. In fact, synaptic alteration is thought to be central to neural disease processes. In particular, the alteration of the structural and functional phenotype of the presynaptic terminal is a highly significant evidence for neural diseases. In this review, we specifically describe structural and functional alteration of nerve terminals in several neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), Amyotrophic lateral sclerosis (ALS), and Huntington's disease (HD).

• The Mathematical Education
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• v.52 no.1
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• pp.19-41
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• 2013

What is the foundation of mathematical thinking? Is it logic based symbolic language system? or does it rely more on mental imagery and visuo-spatial abilities? What kind of neural changes happen if someone's mathematical abilities improve through practice? To answer these questions, basic cognitive processes including long term memory, working memory, visuo-spatial perception, number processes are considered through neuropsychological outcomes. Neuronal changes following development and practices are inspected and we can show there are neural networks critical for the mathematical thinking and development: prefrontal-anterior cingulate-parietal network. Through these inquiry, we can infer the answer to our question.