• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.11
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• pp.2168-2174
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• 2009

Electrical railway system consists of rolling stock, track, signal and streetcar line system. Track circuit system is a vital system due to checking the location of trains. Track circuits are divided by using frequency and isolated electrically. Currently, there is not a regulation for the distance between track circuits using identical frequency. In case of installing additional track circuits in large stations or marshalling yard, the problem which is that the signal is not exactly transmitted to the track circuit occurs due to the mutual interference. In other words, the track circuit properly is not operated on account of wrong induction current by the mutual inductance between track circuits. In this paper, we suggest the electrical model between track circuits and numerically calculate demanded parameters in electrical model. The distance between track circuits satisfying the mutual inductance which does not happen to the mutual interference phenomenon is presented about the distance of track circuit. It is proved by using Matlab and PSpice program as the amplitude of mutual induced current.

• Journal of Korean Society of Forest Science
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• v.95 no.5
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• pp.532-538
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• 2006

Triphala is an important combination of three important forest fruits, i.e., Emblica officinalis, Terminalia chebula and Terminalia bellirica. Chittagong region in Bangladesh was once rich in triphala trees presently subject to the depletion. Thus, these forest resources are being threatened day by day. The study was conducted to learn the present using pattern of the triphala, causes of its depletion and the conservation strategies agreed by the villagers. Eight major uses of triphala trees were recognized. It was revealed that 100% respondents used the triphala as fruit tree followed by 71-78% as fuelwod. The present status of growing stock of triphala was found in depleted condition particularly in the Muslim dominated area. It was found that unawareness was the major cause for depleting the triphala trees agreed by the 87% respondents followed by depleting the village groves by 84%. Awareness creation (100%) and induction of social forestry program (92%) were found major recomendations by the vilagers to retard depleting the triphala tree species in the Chittagong region of Bangladesh.

• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.763-768
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• 2024

This study utilized Q methodology to analyze subjectivity and understand the various factors contributing to the employment difficulties faced by college students majoring in digital content, particularly focusing on practical education. The original data was obtained by administering a Q sample, designed around employment stress and job anxiety, to a purposively selected P sample of 31 individuals, who sorted and classified the statements. The analysis yielded four distinct types: 'lack of practical experience,' 'lack of employment and practical skills,' 'impaired career decision-making and weak will,' and 'lack of mentors and employment information.' Based on these types, the study suggests several implications and solutions, including facilitating student participation in internship programs, offering induction and non-curricular program education, conducting career exploration workshops, and expanding senior mentoring opportunities.

• Radiation Oncology Journal
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• v.21 no.3
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• pp.227-237
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• 2003

Purpose: The human chronic myelogenous leukemia cell line, K562, expresses the chimeric bcr-abl oncoprotein, whose deregulated protein tyrosine kinase activity antagonizes via DNA damaging agents. Previous experiments have shown that nanomolar concentrations of herbimycin A (HWA) coupled with X-irradiation have a synergistic effect in inducing apoptosis in the Ph-positive K562 leukemia cell line, but genistein, a PTK inhibitor, is non selective for the radiation-induced apoptosils on $p210^{bcr/abl}$ protected K562 cells. In these experiments, the cytoplasmic signal transduction pathways, the Induction on a number of transcription factors and the differential gene expression in this model were investigated. Materials and Methids: K562 cells in the exponential growth phase were used in this study. The cells were irradiated with 0.5-12 Gy, using a 6 Mev Linac (Clinac 1800, Varian, USA). Immediately after irradiation, the cells were treated with $0.25/muM$ of HMA and $25/muM$ of genistein, and the expressions and the activities of abl kinase, MAPK family, NF- kB, c-fos, c-myc, and thymidine kinase1 (TK1) were examined. The differential gene expressions induced by PTK inhibitors were also investigated. Results: The modulating effects of herbimycin A and genistein on the radiosensitivity of K562 cells were not related to the bcr-abl kinase activity. The signaling responses through the MAPK family of proteins, were not involved either in association with the radiation-induced apoptosis, which is accelerated by HMA, the expression of c-myc was increased. The combined treatment of genistein, with irradiation, enhanced NF- kB activity and the TK1 expression and activity. Conclusion: The effects of HMA and genistein on the radiosensitivity on the K562 cells were not related to the bcr-abl kinase activity in this study, another signaling pathway, besides the WAPK family responses to radiation to K562 cells, was found. Further evaluation using this model will provide valuable information for the optional radiosensitization or radioprotection.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.29 no.6
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• pp.421-429
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• 2003

Purpose : Neoadjuvant chemotherapy is commonly used to treat cancer patients as adjunct treatment, but if the microvascular tissue transfer is performed simulataneously with cancer resection surgery, the induction chemotherapy might affect the survival rate of vascularized free flap. Our study will focus on the effect of induction chemotherapy on the free flaps which were made on white rat abdomen after injection of 5-FU. Materials and Methods: The experimental rat groups were divided into three groups (total 24 rats) as a normal control group, 24 hrs group after 5-FU injection, 3 days group after 5-FU injection. Inferior abdominal island flaps of 8 Sprague Dawley rats on each group were made and immediately were induced into an ischemic state by clamping the supplying inferior epigastric artery and vein with microvascular clamp for a hour to induce a similiar free flap circumstance, then the inferior abdominal skin flaps were reperfused by releasing the clamps. The flaps on abdomen were repositioned and sutured. The experimental data for flap survival rate was collected by digital photo taking, analysed by computer image program to compare with the flap luminosity. The rats were sacrificed at 3 days, 5 days, 7 days after flap preparation and specimens of the flap were taken and stained with H-E staining. The microscopic finding was made under magnification of 200 and 400. Results: 1. Gross findings on each groups showed the healing condition was good as following sequences; normal, 24 hrs group after chemotherapy, 3 days group after chemotherpy. 2. The values of flap luminosity for evaluation of flap survival rate also showed the same sequences as gross findings of healing state. 3. The microscopic findings of epidermis necrosis, inflammation state, dermis fibrosis, vessel change, fatty tissue layer thinning were compared with each group. The 3 days group after chemotherapy showed remarkably poor healing condition compared to other groups. Conclusion: Chemotherapy agents affected the healing process of free flap, but healing condition was recovered spontaneously as post-injection periods passed out. In opposite to our expectation, 3 days group showed the bad flap condition in comparing with 24 hours group which was considered as immatured body circulation state of chemotherapy agent. It showed that 3 weeks in human being after chemotherapy was not proper as timing of microvascular tissue transfer if 3 days group in rat was considered as same healing period of 3 weeks in human being. More delayed healing timing than 3 weeks might be required in clinical application of free tissue transfer.

• Journal of Plant Biotechnology
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• v.38 no.1
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• pp.62-68
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• 2011

Calmodulin (CaM), a $Ca^{2+}$ binding protein in eukaryotes, mediates cellular $Ca^{2+}$ signals in response to a variety of biotic and abiotic external stimuli. The $Ca^{2+}$-bound CaM transduces signals by modulating the activities of numerous CaM-binding proteins. As a CaM binding protein, AtCBP63 ($\b{A}$rabidopsis thaliana $\b{C}$aM-binding protein $\underline{63}$ kD) has been known to be positively involved in plant defense signaling pathway. To investigate the pathogen resistance function of AtCBP63 in potato, we constructed transgenic potato (Solanum tuberosum L.) plants constitutively overexpressing AtCBP63 under the control of cauliflower mosaic virus (CaMV) 35S promoter. The overexpression of the AtCBP63 in potato plants resulted in the high level induction of pathogenesis-related (PR) genes such as PR-2, PR-3 and PR-5. In addition, the AtCBP63 transgenic potato showed significantly enhanced resistance against a pathogen causing bacterial soft rot, Erwinia carotovora ssp. Carotovora (ECC). These results suggest that a CaM binding protein from Arabidopsis, AtCBP63, plays a positive role in pathogen resistance in potato.

• Korean Journal of Microbiology
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• v.47 no.4
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• pp.342-347
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• 2011

T cells play a key role in viral infection. However, in patients with chronic hepatitis C virus (HCV) infection, HCV-specific T cells are dysfunctional and impaired in the liver, which is the primary site for HCV replication. There are multiple potential mechanisms for HCV-specific T cell dysfunction including induction of immune inhibitory pathways (program death-1; PD-1, cytotoxic t lymphocyte associated antigen-4; CTLA-4) and immune tolerance induced specific for the liver. However, the interaction between hepatocytes and HCV-specific CD8 T cells has not clearly established. In this study, we confirmed huh (human hepatoma) 7.5 cells expressing HLA (human leukocyte antigen) A2 presented antigen to activate HCV-specific CD8 T cells in HLA A2-restricted manner and expression of PD-L (program death ligand) 1 on huh7.5 cells reduced HCV-specific CD8 T cell activation, suggesting an immune modulatory activity. Loss of HCV-specific tetramer responses following antigenic stimulation correlated with increased caspase-3 activity. In addition, PD-L1 on huh7.5 cells rescued HCV-specific CD8 T cells from apoptosis. Our results suggest that the interaction between PD-L1 and PD-1 can recover the function of HCV-specific CD8 T cells in the liver, which could be applied in therapy of HCV chronic infection.

• Journal of Life Science
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• v.21 no.10
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• pp.1494-1499
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• 2011

${\beta}$-lapachone, a quinone of lapachol extracted from the bark of the lapacho tree, has been found to induce apoptosis in various human cancer cells. In the present study, we investigated further possible mechanisms by which ${\beta}$-lapachone exerts its pro-apoptotic action in cultured human lung cancer A549 cells. ${\beta}$-lapachone treatment resulted in inhibition of growth and induction of apoptosis in a concentration-dependent manner, as determined by MTT assay and flow cytometry analysis. The induction of apoptosis by ${\beta}$-lapachone was associated with up-regulation of the expression of p53 and p21 in both transcriptional and translational levels, and the phosphorylation of p53. In addition, ${\beta}$-lapachone activated caspase-3 and -9, and induced degradation of caspase-3 target proteins such as poly (ADP-ribose) polymerase (PARP) and ${\beta}$-catenin. Furthermore, ${\beta}$-lapachone treatment caused a progressive decrease in the expression levels of cyclooxygenase (COX)-2 without significant changes in the levels of COX-1, which was correlated with a decrease in prostaglandin E2 synthesis. Taken together, these results indicated that ${\beta}$-lapachone may have therapeutic potential in human lung cancer treatment.

• Korean journal of applied entomology
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• v.55 no.2
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• pp.177-188
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• 2016

The alpha-proteobacterium Wolbachia is one of the most important intracellular symbionts of arthropods. This Gram-negative bacterium is involved in many biological processes and is currently considered as a potential tool for biological control. Wolbachia is a cytoplasmic bacterium, maternally transferred through generations, and to facilitate its success, it has evolved several strategies that manipulate its host reproductive system to increase the number of infected individuals in the host population. The variety of Wolbachia was first recognized using genes wsp, 16S rRNA, ftsZ, gltA and groEL as molecular markers while strain genotypes of Wolbachia are determined of Multilocus sequence typing (MLST) and sequence of amino acid in region, hyper variable regions (HVRs) in protein WSP. Possible uses of the bacteria and their predominant phenotypes in control programs for agricultural pests and human disease vectors have been considered. Phenotypes are known to induce cytoplasmic incompatibility (CI), parthenogenesis induction (PI), feminization (F) and male killing (MK). Finally, applications of the bacterium in control programs of agricultural and medical insect pests have been discussed.

• Journal of Oriental Neuropsychiatry
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• v.20 no.2
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• pp.111-120
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• 2009

Objectives : This study was performed to investigate the effects of Needle Electrode Electrical Stimulation (NEES) on ischemia-induced cerebrovascular accidents. After obstruction and reperfusion of ${\ast}{\ast}$ arteries in white mice, the amounts of necrosis and inflammation related substances IL-6, Caspase-3, and PARP, C-fos were measured in neurons of the hippocampus. The following results were obtained. Methods : This study used 21 male specific pathogen free (SPF) SD (Sprague Dawley) rats, 8 weeks of age and approximately 300 g in weight, that were given at least 1 week to adapt to the lab environment Each exposed artery was completely occluded with non-absorbent suture thread and kept in that state for 5 minutes. The sutures were then removed to allow reperfusion of blood. Test group is control group for comparison with the common carotid artery occlusion models, a GI group that underwent common carotid artery occlusion, and a needle electrode electrical stimulation (NEES) group that underwent NEES after artery occlusion. The GI and NEES groups were given 12, 24, or 48 hours of reperfusion before NEES. NEES device (PG6, ITO, Japan, 9V, current, 2Hz) was used to stimulate the right and left acupoint ST36 of the SD rats for 30 minutes while they were sedated with 3% isoflurane. An immunohistochemistry test was done on the forebrains of the GI induced rats. All the data collected from this study was symbolized and analyzed using a statistics processing program (SPSS 12.0K/PC). The level of significance was set at ${\alpha}$=0.05 and a T-TEST analysis was used to find out the effects of treatment on each of the groups: the normal group, the CVA induced group, and the treatment after CVA induction group. Results : Both PARP and C-fos immuno-reactive cells, related to apoptosis, were greater in the GI groups than the NEES group. Caspase and IL-6 immuno-reactive cells, related to inflammation, were greater in the GI and NEES groups than the control group. Conclusions : This research was conducted to study the effects of NEES on CVA due to ischemia. Occlusion and reperfusion was performed on the common carotid arteries of white rats, after which amounts of substances related to neuron necrosis and inflammation - PARP, IL-6, Caspase-3, and C-fos - were measured in the Hippocampus