• Journal of Acupuncture Research
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• v.24 no.6
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• pp.137-148
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• 2007

Objectives : Following central nervous system (CNS) injury, inhibitory influences at the site of axonal damage occur. Glial cells become reactive and form a glial scar, know as gliosis. As well,myelin debris such as MAG inhibits axonal regeneration. Astrocyte-rich gliosis relates to up-regulation of GFAP and CD81, and eventually becomes a physical and mechanical barrier to axonal regeneration. It is postulated that when the astrocytic reaction is absent, regeneration of axons can occur. It was reported that treatment with anti CD81 antibodies enhanced functional recovery in rats with spinal cord injury. Methods : MAG is one of several endogenous axon regeneration inhibitors that limit recovery from central nervous system injury and disease. It was reported that molecules which block such inhibitors enhanced axon regeneration and functional recovery. Results : In this current study, the author investigated the effect of the water extract of Ginseng Radix on the regulation of CD81, GFAP and MAG which increases when gliosis occurs. MTT analysis was performed to examine cell viability, and cell based ELISA, Western Blot and PCR were used to detect the expression of CD81, GFAP and MAG. Immunohistochemistry was also performed to confirm in vivo. Conclusions : We observed that Ginseng Radix significantly down-regulates the expression of CD81, GFAP and MAG by means of cell based ELISA, Western Blot and PCR. In immunohistochemistry, expression of CD81, GFAP and MAG also decreased. Taken together, these results suggest that Ginseng Radix can be a candidate for regenerating CNS injury.

• Korean Chemical Engineering Research
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• v.48 no.6
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• pp.679-683
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• 2010

In this study, calcination temperature dependence of TS-1 catalyst was investigated in the hydroxylation of phenol with hydrogen peroxide during the regeneration of catalyst. Catalyst was regenerated 5 times by calcining at $550^{\circ}C$ and $700^{\circ}C$, respectively. When the catalyst was regenerated at $550^{\circ}C$ after 5th regeneration phenol conversion was decreased from 22.9% to 15.1% and at $700^{\circ}C$ after 5th regeneration phenol conversion was decreased from 22.9% to 18.8%. For formation ratio of catechol/hydroquinone was increased from 1.28 to 1.45 after 5th regeneration at $550^{\circ}C$, and from 1.28 to 1.20 after 5th regeneration at $700^{\circ}C$. The main reasons for deactivation of the catalyst were suggested by analyzing chemical/physical properties with XRD, UV-vis spectra, $N_2$ adsorption/desorption and TGA, and evaluating the catalytic activity such as phenol conversion and product selectivity.

• Journal of International Academy of Physical Therapy Research
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• v.3 no.1
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• pp.345-355
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• 2012

This study purposed to examine the effect of low power laser on pain response and axonal regeneration. In order to prepare peripheral nerve injury models, we crushed the sciatic nerve of Sprague-Dawley rats and treated them with low power laser for 21 days. The rats were divided into 4 groups: normal group(n=10); control group(n=10) without any treatment after the induction of sciatic nerve crush injury; experimental group I(n=10) treated with low power laser(0.21$mJ/mm^2$) after the induction of sciatic nerve crush injury; and experimental group II(n=10) treated with low power laser(5.25$mJ/mm^2$) after the induction of sciatic nerve crush injury. We measured spontaneous pain behavior(paw withdrawal latency test) and mechanical allodynia(von Frey filament test) for evaluating pain behavioral response, and measured the sciatic function index for evaluating the functional recovery of peripheral nerve before the induction of sciatic nerve crush injury and on day 1, 7, 14 and 21 after the induction. After the experiment was completed, changes in the H & E stain and toluidine blue stain were examined histopathologically, and changes in MAG(myelin associated glycoprotein) and c-fos were examined immunohistologically. According to the results of this study, when low power laser was applied to rat models with sciatic nerve crush injury for 21 days and the results were examined through pain behavior evaluation and neurobehavioral, histopathological and immunohistological analyses, low power laser was found to affect pain response and axonal regeneration in both experimental group I and experimental group II. Moreover, the effect on pain response and axonal regeneration was more positive in experimental group I to which output 0.21$mJ/mm^2$ was applied than in experimental group II to which 5.25$mJ/mm^2$ was applied.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.7A
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• pp.951-958
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• 2000

In wavelength-routed all-optical networks, signals are transmitted on a direct optical path, or a lightpath, in a single-hop manner without opto-electronic/electro-optic(OE/EO) conversion at intermediate nodes. However, due to the physical constraints of optical elements such as ASE noise and crosstalk signals can be degraded un a long path. To establish a connection under such impairments, the optical signal may need to be regenerated at intermediate nodes, dividing a lightpath into two or more fragments. However, since signal regeneration at intermediate nodes requires additional network resources, the selection of these nodes should be made carefully to minimize blocking of other lightpaths. In this paper, we deal with the problem of establishing a lightpath in a multihop manner under physical constraints. We provide both minimal-cost and heuristic algorithms for locating signal regeneration nodes(SRNs). For a minimal-cost algorithm, we formulate the problem using dynamic programming(DP) such that blocking of other lightpaths due to the lack of transmitters/receivers(TXs/RXs) and wavelengths is minimized throughout the network.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.33 no.3
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• pp.104-109
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• 2023

Electrospinning was performed using an eco-friendly solvent composed of acetic acid, ethyl acetate and distilled water to investigate the effect of gelatin concentration on mechanical properties and cytotoxicity of absorbable poly(D,L-lactic acid) (PDLLA)/gelatin blend membrane. The tensile stress, strain at break, and WUC of the PDLLA/gelatin (97/3) scaffold at 26 wt% concentration were determined to be 3.9 ± 0.7 MPa, 37 ± 1.3 %, and 273 ± 33 %, respectively. FT-IR results revealed that PDLLA and gelatin were bound only by van der Waals interactions. The cell viability of PDLLA/gelatin membranes containing 0 %, 1 %, 2 %, 3 %, and 4 % gelatin were more than 100 %, which makes all membranes highly suitable as a barrier membrane for absorbable periodontal tissue regeneration due to their marketed physical properties and biocompatibility.

• Journal of Korean Physical Therapy Science
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• v.14 no.1_4
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• pp.11-23
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• 2007

This study was performed to evaluate the effects of low-intensity ultrasound application to the peripheral nerve injury animal model on enhancement of nerve regeneration and functional recovery. Using aseptic microsurgical techniques, the sciatic nerve of adult male Sprague-Dawley rats was crushed at the outside of right mid-thigh for 30 seconds with fine forceps. Beginning just after surgery, various continuous-wave ultrasound treatments with intensities of 0.2 W/$cm^2$, 0.5 W /$cm^2$ and 1.0 W /$cm^2$ operated at 1 MHz or sham treatment were applied to the opposite inside of the crush site for 1 minute every other day with a transducer moving speed of 2cm/sec. For evaluation of the progress of sciatic nerve regeneration, c-Fos expression in the lumbar spinal cord (L4-5) dorsal horn was investigated. c-fos expression was markedly increased at 1hour after sciatic nerve crush injury, then gradually decreased thereafter. The c-fos expressions were significantly decreased (p<0.05) in all the experimental groups in comparison with the control group until 3days post-crush, and the degrees of decrease were higher in 0.5 W/$cm^2$ and 1 W/$cm^2$ intensity ultrasound application groups. It is suggested that low-intensity ultrasound application to an animal model of sciatic crush injury may suppress pain transmission and promote nerve regeneration, and which may result in delayed progress of muscle atrophy and accelerated progress of muscle recovery and eventually may result in accelerated and improved foot function recovery.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.2
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• pp.28-48
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• 2019

This research is aimed at identifying the perception associated with urban regeneration and predicting policy implications of future directions by analyzing the trend of urban regeneration depicted in the mass media by utilizing SNA (Semantic-Network Analysis) techniques. As the number of articles has increased, it is noted through analysis that the interrelationships between social phenomena and issues have combined to form the meaning of urban regeneration. Overall, 'urban' and 'regeneration' keywords also appeared at different periods, with 'urban' closely related to 'regeneration' starting in 1970 when urbanization was becoming more prevalent. It was analyzed that the frequency of 'urban' appeared more frequently in the early 1990s, while the frequency of 'rural' decreased sharply. Until the 1990s, the slums and the recession that appeared as side effects of urban problem-solving policies were mostly concentrated in cities. Policy discussions were conducted with the goal of improving the physical environment of cities rather than concentrating on the surrounding rural areas. The distributions of the keywords 'development' and 'regeneration' have increased quantitatively since the 1970s, and urban polarization has exploded due to the development of the external growth of cities, mirroring the trend of accelerated environmental threats. In particular, the keywords for 'regeneration' emerged mainly related to environmental problems, which led to the need for urban regeneration, and environmentally and ecologically friendly development. The emergence of "urban," "regeneration" and "environment" as keywords having to do with urban regeneration grew in the 1990s. This suggests that urban regeneration is now linked to "environment", as that has become a social issue.

• Land and Housing Review
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• v.13 no.1
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• pp.23-38
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• 2022

As city tourism has recently been evaluated as a major indicator of urban competitiveness, strengthening the role of cities as tourist destinations has received more attention. However, industrialization and urbanization of many cities lead to population decline, extinction of traditional industries, and deterioration of living environments, weakening urban functions and competitiveness. Thus, it is essential for declining cities to build a measure to restore urban competitiveness by enhancing urban functions. Accordingly, this study focused on socio-cultural urban regeneration by exploring physical spaces for tourism destinations in declining cities. Different from general tourist destinations, tourism destinations of urban regeneration have a temporal perspective covering the past, present, and future. How does the temporal perspective of urban regeneration tourist destinations affect tourists' satisfaction and behavioral intention? In order to address these questions, this study conducts an empirical analysis based on structural equation modeling (SEM) using the sample of tourists who have visited urban regeneration tourism destinations. With SEM, this paper investigates structural relationships across variables by testing the hypothesis established in the proposed research model. The results show that precious memories of the past are the most important factor for tourists to visit urban regeneration tourist destinations. The empirical findings of this study will contribute to the research areas of urban tourism, urban regeneration tourism, and urban regeneration tourism destinations. In addition, this study can provide practical implications to develop socio-cultural contents of urban regeneration areas as tourism resources to establish plans for urban regeneration projects and achieve sustainable development strategies.

• Journal of the Korean Institute of Rural Architecture
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• v.23 no.2
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• pp.9-16
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• 2021

The purpose of this study is to maintain the existing characteristics of the city by utilizing the physical decline status and floating population in small and medium cities residential areas. In addition, it intends to present the direction of flexible urban regeneration and maintenance by reflecting regional characteristics and current status. A total of three data were used in this study. Building data, floating population data, and census output area data were used. Building data and floating population data were classified into five classes. The graded data were joined to the census output area data and analyzed by overlapping the two data. As a result of analysis of 17 residential areas in 5 small and medium cities in Jeollanam-do, 4 types, 2 management models, and 4 indicators could be presented by grade and regional characteristics. This study is meaningful in that it is possible to plan regionally customized urban regeneration/maintenance management plans and projects through the typology of the current status and characteristics of the region, which is an important step in the bottom-up form.

• Journal of the Korean Society of Visualization
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• v.20 no.2
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• pp.70-77
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• 2022

Skeletal muscle tissues feature cellular heterogeneity, including differentiated myofibers, myoblasts, and satellite cells. Thanks to the presence of undifferentiated myoblasts and satellite cells, skeletal muscle tissues can self-regenerate after injury. In skeletal muscle regeneration, the collective motions among these cell types must play a significant role, but little is known about the dynamic collective behavior during the regeneration. In this study, we constructed in vitro platform to visualize the migration behavior of skeletal muscle cells in specific conditions that mimic the biochemical environment of injured skeletal muscles. We then visualized the spatiotemporal distribution of stresses arising from the differential collectiveness in the cellular clusters under different conditions. From these analyses, we identified that the heterogeneous population of muscle cells exhibited distinct collective migration patterns in the injury-mimicking condition, suggesting selective activation of a specific cell type by the biochemical cues from the injured skeletal muscles.