• Molecules and Cells
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• v.43 no.3
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• pp.276-285
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• 2020

Circadian rhythm is an endogenous oscillation of about 24-h period in many physiological processes and behaviors. This daily oscillation is maintained by the molecular clock machinery with transcriptional-translational feedback loops mediated by clock genes including Period2 (Per2) and Bmal1. Recently, it was revealed that gut microbiome exerts a significant impact on the circadian physiology and behavior of its host; however, the mechanism through which it regulates the molecular clock has remained elusive. 3-(4-hydroxyphenyl)propionic acid (4-OH-PPA) and 3-phenylpropionic acid (PPA) are major metabolites exclusively produced by Clostridium sporogenes and may function as unique chemical messengers communicating with its host. In the present study, we examined if two C. sporogenes-derived metabolites can modulate the oscillation of mammalian molecular clock. Interestingly, 4-OH-PPA and PPA increased the amplitude of both PER2 and Bmal1 oscillation in a dose-dependent manner following their administration immediately after the nadir or the peak of their rhythm. The phase of PER2 oscillation responded differently depending on the mode of administration of the metabolites. In addition, using an organotypic slice culture ex vivo, treatment with 4-OH-PPA increased the amplitude and lengthened the period of PER2 oscillation in the suprachiasmatic nucleus and other tissues. In summary, two C. sporogenes-derived metabolites are involved in the regulation of circadian oscillation of Per2 and Bmal1 clock genes in the host's peripheral and central clock machineries.

• Physical Therapy Korea
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• v.30 no.4
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• pp.306-313
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• 2023

Background: As social problems due to the acceleration of the aging era and the increase in the elderly population are becoming serious, virtual reality (VR)-based healthcare is emerging as an approach for preventing and managing health issues. Objects: This study used validity and reliability analyses to examine the clinical efficacy that is, the clinical value and usability of a novel VR cognitive evaluation system index that we developed. Methods: We developed a VR cognitive evaluation system based on motion recognition analysis evaluation for individuals aged 65 to 85. After conducting the Korean version of the Mini-Mental State Exam (K-MMSE) cognitive evaluation, the evaluation score was verified through correlation analysis in the VR cognitive evaluation system. To verify the construct validity of the two groups, the Global Deterioration Scale (GDS) grades were categorized into a normal cognitive group (GDS grade 1) and a cognitive impairment group (GDS grades 2 and 3). The data were measured twice to determine the reliability between the two measurements and assess the stability and clinical value of the evaluation system. Results: Our evaluation system had a high correlation of 0.85 with the widely used K-MMSE cognitive evaluation. The system had strong criterion-related validity at the 95% confidence interval. Compared to the average score of GDS grade 1 in the VR cognitive evaluation system, the average score of GDS grades 2 and 3 in the VR cognitive evaluation system was statistically significantly lower while also having strong construct validity at the 95% confidence interval. To measure the reliability of the VR cognitive evaluation system, tests-retests were conducted using the intraclass correlation coefficient (3,1), which equaled 0.923 and was statistically significant. Conclusion: The VR cognitive evaluation system we developed is a valid and reliable clinical tool to distinguish between normal cognitive status and mild cognitive impairment.

• Biomedical Science Letters
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• v.23 no.3
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• pp.281-285
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• 2017

The purpose of the current study is to investigate the cognition-enhancing effects of Ixeris dentata (Thunb) Nakai in scopolamine-induced amnesic mice. Scopolamine (2 mg/kg, i.p.) was used to induce amnesia in mice. The cognitive-enhancing activity of the IDE (10, 20 and $40{\mu}g/mL$) was studied by passive avoidance response, elevated plus maze and Y-maze behavioral paradigm in normal and scopolamine-induced amnesic mice. Scopolamine-induced cognitive deficits were significantly reversed by IDE (P < 0.001 at 20 mg/kg) in a dose-dependent fashion in all the behavioral paradigms tested. IDE possesses cognitive-enhancing properties in amnesic mice due to its potent antioxidant action.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2010.05a
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• pp.60-65
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• 2010

Language learning involves linguistic environments around the learner. So the variation in training input to which the learner is exposed has been linked to their language learning. We explore how linguistic experiences can cause differences in learning linguistic structural features, as investigate in a probabilistic graphical model. We manipulate the amounts of training input, composed of natural linguistic data from animation videos for children, from holistic (one-word expression) to compositional (two- to six-word one) gradually. The recognition and generation of sentences are a "probabilistic" constraint satisfaction process which is based on massively parallel DNA chemistry. Random sentence generation tasks succeed when networks begin with limited sentential lengths and vocabulary sizes and gradually expand with larger ones, like children's cognitive development in learning. This model supports the suggestion that variations in early linguistic environments with developmental steps may be useful for facilitating language acquisition.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.5
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• pp.2047-2066
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• 2016

In this paper, we investigate joint power allocation and relay selection (PARS) schemes in non-orthogonal cooperative protocol (NOCP) based cognitive relay networks. Generally, NOCP outperforms the orthogonal cooperative protocol (OCP), since it can provide more transmit diversity. However, most existing PARS schemes in cognitive relay networks focus on OCP, which are not suitable for NOCP. In the context of NOCP, we first derive the joint constraints of transmit power limit for secondary user (SU) and interference constraint for primary user (PU). Then we formulate optimization problems under the aforementioned constraints to maximize the capacity of SU in amplify-and-forward (AF) and decode-and-forward (DF) modes, respectively. Correspondingly, we derive the closed form solutions with respect to different parameters. Numerical results are provided to verify the performance improvement of the proposed PARS schemes.

• International Journal of Computer Science & Network Security
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• v.21 no.4
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• pp.223-228
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• 2021

As a consequence of sudden outbreak of COVID-19 pandemic worldwide, educational institutes around the globe are forced to switch from traditional learning systems to e-learning systems. This has led to a variety of technology-driven pedagogies in e-teaching as well as e-learning. In order to take the best advantage, an appropriate understanding of the cognitive capability is of prime importance. This paper presents an intelligent cognitive maturity recognition system for confidence-based e-learning. We gather the data from actual test environment by involving a number of students and academicians to act as experts. Then a Genetic Programming based simulation and modeling is applied to generate a generalized classifier in the form of a mathematical expression. The simulation is derived towards an optimal space by carefully designed fitness function and assigning a range to each of the class labels. Experimental results validate that the proposed method yields comparative and superior results which makes it feasible to be used in real world scenarios.

• Journal of Korean Biological Nursing Science
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• v.18 no.4
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• pp.274-279
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• 2016

Purpose: Adolescents who experienced the alcohol consumption have gradually increased. Adolescence is a critical period of the neural plasticity in the brain. Neural plasticity is mediated by neurotrophins and has an impact on cognitive function. Environmental enrichment ameliorates the cognitive function and increases neurotrophins. Thus, we investigated the neuroprotective effect of environmental enrichment on ethanol induced cognitive impairment in adolescent rats. Methods: The ethanol groups and the controls groups were injected with ethanol (0.5g/kg) and phosphate buffered saline, respectively, through intraperitoneal from 28th day of birth for 11 days. The environmental enrichment groups were provided larger cages containing toys than the standard cage. Passive avoidance test and Y-maze test were performed to evaluate the spatial memory. Results: Environmental enrichment+ethanol group showed higher alterations than the standard environment+ethanol group in Y-maze test (p<.05). In hippocampus, The environmental enrichment+ethanol group showed significantly higher level of the number of c-fos positive celsl and density of tropomyosin receptors kinase B receptor than the standard environment+ethanol group (p<.05). Conclusion: So, we suggested that the environmental enrichment played a role as a prophylaxis for prevention of memory impairment induced by ethanol exposure in adolescence.

• Journal of The Korean Association For Science Education
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• v.18 no.3
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• pp.261-271
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• 1998

This study investigated the influences of applying the Cognitive Conflict Process Model (the Procedural Teaching Model using Cognitive Conflict Strategy: Kwon, 1989) upon students' achievement and attitudes in a middle school science concept instruction. For the treatment group, science instruction to apply the Cognitive Conflict Process Model was used. For the control group, traditional instruction was used. Prior to instruction, students' pre-conceptions test and attitudes test related to the science were administered. After instruction, the above two tests and the regular examinations were measured. Also students' perceptions of their teacher's new teaching style was investigated by questionnaire. But, above all, the main purpose of this study was to investigate the principal accompanying matters of general application of the teaching model to science concept instruction rather than conceptual and attitudinal change. Therefore, this study identified necessary conditions of applying the teaching model to science instruction.

• Journal of the Korean Chemical Society
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• v.51 no.6
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• pp.549-559
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• 2007

The purpose of this study was to investigate cognitive acceleration effect of the experimental group over three years compared with the control group through the ‘Thinking Science' program in the middle school students. The ‘Thinking Science' program was implemented to 168 students in 7th grade over a period of two years. After implementation of the ‘Thinking Science' program, the improvement of formal thinking ability of the students was almost twice examined with SRT VII as the post-test and the delayed test. It was shown that by the end of the implementation period the experimental group had achieved a significantly greater gain score in levels of cognitive development than had the control group. In the subsequent year during which there was no further implementation, the experimental group continued to develop at the same rate as the control group. However, it is clear that much more experimental students in mature concrete operational stage shifted to formal operational stage in delayed test. The results were also analyzed by gender, and cognitive levels of the students. In the post-test, the ratio of girls that shifted to formal operation stage in the experimental group increased as compared with the ratio of boys, while, in the delayed test cognitive level of boys was more effective than that of girls.

• Korean Journal of Cognitive Science
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• v.23 no.3
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• pp.367-388
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• 2012

The centennial of Alan Mathison Turing(23 June 1912 - 7 June 1954) is an appropriate occasion on which to assess his profound influence on the development of cognitive science. His contributions to and attitudes toward that field are discussed from the metamathematical perspective. This essay addresses (i)Turing's mathematical analysis of cognition, (ii)universal Turing machines, (iii)the limitations of universal Turing machines, (iv)oracle Turing machine beyond universal Turing machine, and (v)Turing test for cognitive science. Turing was a ground-breaker, eager to move on to new fields. He actually opened wider the scientific windows to the mind. The results show that first, by means of mathematical logic Turing discovered a new bridge between the mind and the physical world. Second, Turing gave a new formal analysis of operations of the mind. Third, Turing investigated oracle Turing machines and connectionist network machines as new models of minds beyond the limitations of his own universal machines. This paper explores why the cognitive scientist would be ever expecting a new Turing Test on the shoulder of Alan Turing.