• PNF and Movement
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• v.6 no.3
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• pp.37-51
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• 2008

Purpose : This paper focuses on the emerging concept that adult central nervous system neurogenesis can be regulated by various physical activity, enriched environment, and pathological conditions. Neurogenesis-the production of new neuron-is an ongoing process that persists in the adult brain of mammalian, including humans. Result : The adult brain was thought be limited in its regenerative function. However, this concepts changed, recent evidence of neurogenesis in certain adult brain areas such as SVZ(subventricular zone) and SGZ(subgranular zone) in hippocampus, raised possibility for improved treatment for patient with stroke. Neural plasticity has an adaptive purpose, because an ability of the brain to change in response to peripheral stimulation, physical activity, experience, and injury. Conclusions : The major function of the neurogenesis in adult brain seems to be replacing the neuron that die regularly in discrete adult brain regions. These cells are capable of functionally integrating into neighboring neural cells, and reconnecting to the correct neural networks. This review suggest that various intervention, including physical activity, voluntary movement training, skilled forelimb reaching training, and enriched environment, induced neural cell production in certain adult brain, and associated with functional recovery after stroke.

• Journal of Korean Medicine Rehabilitation
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• v.28 no.2
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• pp.105-111
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• 2018

Objectives The purpose of this study was to examine the effects muscle fatigue at the knee muscles on balance during standing in healthy adults. Methods Thirty healthy adults were recruited along with their written informed consent. Subjects were randomly assigned to knee extensor group (fatigue on knee extensor, KE), and knee flexor group (fatigue on knee flexor, KF). And subjects performed exercise with each muscle group until muscle fatigue was induced. They were assessed balance ability by functional reaching test (FRT), limit of stability (LOS), and postural sway (one leg standing, normal eye open (NO), normal eye close (NC), pillow with eye open (FO), and pillow with eye close (FC)) before and after fatigue. Results There were significant group differences balance performances in FRT, anterior of limit of stability, one leg standing, and the muscle fatigue of knee muscles were decreased balance performances. The balance performance was affected by visual sense and proprioception. Conclusions These results show that the muscle fatigue of knee muscles decreased balance performance. Therefore, balance exercise program should be trained without muscle fatigue.

• Journal of Photoscience
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• v.9 no.3
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• pp.65-70
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• 2002

In the rice leaves treated with methyl viologen (MV), the photochemical efficiency of PSII (or $F_{v/}$F $m_{m}$) was significantly decreased, and significant portion of the photoinactivation process was reversible during the dark-recovery. The dark-reactivation process was relatively slow, reaching its plateau after 2-2.5 h of dark incubation. The damaged portion of functional PSII was 13％, based on the value of I/ $F_{o}$- I/ $F_{m}$ after this dark-recovery period. The reversible photoinactivation process of PSII function in the MV-treated leaves consisted of a xanthophyll cycle-dependent development of NPQ and a xanthophyll cycle-independent process. The latter process was reversible in the presence of nigericin. As well as the increase in the values of Chl fluorescence parameters, the epoxidation process during the dark-recovery after the MV-induced photooxidation was very slow. These results suggest that the photooxidative effect of MV is partly protected by the down-regulation of PSII before inducing physical damages in core proteins of PSII.I.I.I.I.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.4
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• pp.543-551
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• 2021

Changes in gluten surface hydrophobicity, which play an important role in the functional characteristics of protein, were measured according to various protein concentrations, pH levels, electrolytes concentrations, and alginate molecular weights using 8-anilino-1-naphthalene sulfonic acid (ANS) as a fluorescent probe. Gluten surface hydrophobicity decreased as gluten concentration increased, reaching a maximum pH of 7.0. The effects of alginate molecular weights and alginate concentration on the surface hydrophobicity, emulsifying activity index (EAI), and emulsion stability index (ESI) of gluten-sodium alginate dispersion (GAD) were measured. Gluten surface hydrophobicity rapidly increased the asl NaCl concentration of gluten solution up to 300 mM and showed no significant increase above 300 mM. However, gluten surface hydrophobicity notably decreased until the concentration of CaCl₂ and MgCl₂ reached 30 mM, indicating no significant variations above 30 mM. GAD surface hydrophobicity increased as the concentration and molecular weight of sodium alginate increased, however, gluten concentration increased as the GAD surface hydrophobicity decreased. The EAI and ESI of GAD increased as both molecular weight and concentration of sodium alginate increased.

• PNF and Movement
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• v.20 no.3
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• pp.383-390
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• 2022

Purpose: The purpose of this study was to examine the effect of three-week contract-and-relax (CR) interventions with and without reinforcement using temporal summation for flexibility and dynamic balance ability in young people with hamstring shortening. Methods: This study was conducted on 20 female college students with hamstring shortening. The participants were divided equally into two groups using stratified randomization: the CR group (CRG) and the CR with reinforcement group (CRRG). All interventions were applied three times a week for three weeks. The passive straight leg raise (PSLR) test and functional reaching test (FRT) were conducted on each participant before and after the three-week intervention. Results: In both groups, PSLR and FRT improved significantly after the three-week intervention compared to before intervention (p < 0.01). The amount of change in PSLR after the three-week intervention was significantly higher in CRRG than in CRG (p < 0.05). Conclusion: Three-week CR interventions with and without reinforcement were effective in improving PSLR and FRT. To improve hamstring shortening, CR intervention with reinforcement may be more useful than CR intervention without reinforcement.

• Membrane and Water Treatment
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• v.14 no.3
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• pp.121-128
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• 2023

This study introduces a NaOH/Zn-assisted hydrothermal method for the synthesis of zeolites derived from coal ash (CA). A zeolite/Zn adsorbent is successfully prepared by the activation of CA with NaOH and Zn; it is characterized by a high surface area and a negative surface charge.Methylene blue (MB) and methyl orange (MO) are selected as dye pollutants, and their adsorption onto the zeolite/Zn adsorbent is investigated. Results show the high adsorption capacities of MB and MO and that the negative surface charge facilitates electrostatic interactions between the adsorbates and adsorbents. The zeolite/Zn adsorbents shows the selective adsorption of positively charged dye MB via electrostatic interactions between the =NH+ group (positive dipole) and the oxygen functional group of the adsorbents (negative dipole). The selectivity for the positively charged dye is sufficiently high, with the removal efficiency reaching 99.41% within 10 min. By contrast, the negatively charged dye MO exhibits negligible absorption. These findings confirm the role of electrostatic interactions in the adsorption of MB, in addition to the effect of a large surface area. The results of this study are expected to facilitate the development of simple, eco-friendly, and cost-effective zeolite-based adsorptive composites from CA residuals for the selective removal of dye pollutants from CA waste.

• Journal of Microbiology and Biotechnology
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• v.33 no.5
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• pp.656-661
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• 2023

The aims of this study were to optimize the preparation of low-molecular-weight collagen using a proteolytic enzyme (alcalase) derived from the feet of Korean native chickens, and to characterize the process of collagen hydrolysis. Foreign bodies from chicken feet were removed using ultrasonication at 28 kHz with 1.36 kW for more than 25 min. The hydrolytic pattern and molecular weight distribution of enzyme-treated collagen from chicken feet were analyzed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and high-performance liquid chromatography, respectively. Ideally, chicken feet should be treated at 100℃ for 8 h to obtain a high collagen content using hot water extraction. The collagen content of the chicken foot extract was 13.9 g/100 g, and the proportion of low-molecular-weight collagen increased with increasing proteolytic enzyme concentration and reaction time. When treated with 1% alcalase, the average molecular weight of collagen decreased rapidly to 4,929 Da within 5 h and thereafter decreased at a slower rate, reaching 4,916 Da after 7 h. Size exclusion chromatography revealed that low-molecular-weight collagen peptides of approximately 1,000-5,000 Da were obtained after hydrolysis with 1% alcalase for 1 h.

• Journal of Intelligence and Information Systems
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• v.28 no.3
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• pp.139-159
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• 2022

As interest in health functional foods has increased since COVID-19, the importance of imported food safety inspections is growing. However, in contrast to the annual increase in imports of health functional foods, the budget and manpower required for inspections for import and export are reaching their limit. Hence, the purpose of this study is to propose a machine learning model that efficiently detects unsuitable food suitable for the characteristics of data possessed by government offices on imported food. First, the components of food import/export inspections data that affect the judgment of nonconformity were examined and derived variables were newly created. Second, in order to select features for the machine learning, class imbalance and nonlinearity were considered when performing exploratory analysis on imported food-related data. Third, we try to compare the performance and interpretability of each model by applying various machine learning techniques. In particular, the ensemble model was the best, and it was confirmed that the derived variables and models proposed in this study can be helpful to the system used in import/export inspections.

• Journal of Food Hygiene and Safety
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• v.38 no.4
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• pp.264-272
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• 2023

The aim of this study was to compare the antioxidant activities and functional contents of Korean conventional and Chinese seed gingers from the Jeollabuk-do Wanju and Chungcheongnam-do Seosan regions. Ginger samples were subjected to steaming treatments for different durations (2-8 h) at 121℃ using an autoclave. The antioxidant activity was evaluated by measuring total polyphenol and flavonoid contents and ABTS and DPPH radical scavenging activities, while functional ingredient contents were analyzed for gingerols and shogaols. The results showed that Wanju conventional seed ginger (WO-2) had the highest total polyphenol (85.24 mg GAE/g) and flavonoid (98.14 RE/100 g) contents, surpassing that of the control in all steamed groups at 6 h. ABTS radical scavenging activity showed a strong correlation with total polyphenol and flavonoid contents. The control groups indicated that Korean conventional seed ginger had 1.0-1.3 times higher gingerol contents compared to Chinese seed ginger. Furthermore, the content of shogaols, considered major functional ingredients, increased significantly with longer steaming durations, reaching the highest content (1,793 mg/kg) at 8 h, which was 1.0-1.8 times higher in Korean conventional seed ginger than that in Chinese seed ginger. These experiments provide valuable data supporting the excellence of Korean conventional seed ginger in the future.

• Investigative Magnetic Resonance Imaging
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• v.16 no.2
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• pp.136-141
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• 2012

Purpose : To investigate the pharmacologic modulation of motor task-dependent physiologic responses by antiplatelet agent, clopidogrel, during hand motor tasks in healthy subjects. Materials and Methods: Ten healthy, right-handed subjects underwent three functional magnetic resonance (fMRI) sessions: one before drug administration, one after high dose drug administration and one after reaching drug steady state. For the motor task fMRI, finger flexion-extension movements were performed. Blood oxygenation level dependent (BOLD) contrast was collected for each subject using a 3.0 T VHi (GE Healthcare, Milwaukee, USA) scanner. $T2^*$-weighted echo planar imaging was used for fMRI acquisition. The fMRI data processing and statistical analyses were carried out using SPM2. Results: Second-level analysis revealed significant increases in the extent of activation in the contralateral motor cortex including primary motor area (M1) after drug administration. The number of activated voxels in motor cortex was 173 without drug administration and the number increased to 1049 for high dose condition and 673 for steady-state condition respectively. However, there was no significant difference in the magnitude of BOLD signal change in terms of peak T value. Conclusion: The current results suggest that cerebral motor activity can be modulated by clopidogrel in healthy subjects and that fMRI is highly senstive to evidence such changes.