• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.5
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• pp.65-72
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• 2006

In new generation vehicle technologies, a fuel cell vehicle becomes more important, by virtue of their emission merits. In addition, a fuel cell is considered as a major source to generate the electricity for vehicles in near future. This paper focuses on modeling of not only an electric vehicle and but also a fuel cell vehicle to estimate performances. And an EV cart is manufactured to verify the modeling. Speed, voltage, and current of the vehicle and modeling are compared to estimate them at acceleration test and driving mode test. The estimations are also compared with the data of the Ballard Nexa fuel cell stack. In order to investigate a fuel cell based vehicle, motor and fuel cell models are integrated in a electric vehicle model. The characteristics of individual components are also integrated. Calculated fuel cell equations show good agreements with test results. In the fuel cell vehicle simulation, maximum speed and hydrogen fuel consumption are estimated. Even though there is no experimental data from vehicle tests, the vehicle simulation showed physically-acceptable vehicle characteristics.

• Journal of Korean Neurosurgical Society
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• v.38 no.1
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• pp.47-53
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• 2005

Objective : Anti-malaria drugs may modulate tumor resistance to chemotherapeutic agents, but it has not been proven effective in the treatment of malignant gliomas. The aim of this study was to determine whether adequate pre-clinical data on co-administration of chemotherapeutic agents with anti-malaria drugs on malignant cell lines could be obtained that would warrant its further potential consideration for use in a clinical trial for malignant gliomas. Methods : Two malignant glioma cell lines [U87MG, T98G] were treated with chemotherapeutic agents alone or with anti-malaria drugs. Cells were incubated with drugs for 4 days. Following the 4-day incubation, drug sensitivity assays were performed using 3-[4,5-dimethyl-2-thiazol-2-yl] 2,5-diphenyltetrazolium bromide [MTT] assay following optimization of experimental conditions for each cell lines and cell viability was calculated. Results : In all of four chemotherapeutic agents[doxorubicin. vincrisitne, nimustine, and cisplatin], the cell viability was found to be markedly decreased when hydroxychloroquine was co-administered on both U87MG and T98G cell lines. The two way analysis of variance[ANOVA] yielded a statistically significant two-sided p-value of 0.0033[doxorubicin], 0.0005[vincrisitne], 0.0007[nimustine], and 0.0003[cisplatin] on U87MG cell lines and 0.0006[doxorubicin], 0.0421[vincrisitne], 0.0317[nimustine], and 0.0001[cisplatin] on T98G cell lines, respectively. However, treatment with chloroquine and primaquine did not induce a decrease in cell viability on both U87MG and T98G cell lines. Conclusion : Our data support further consideration of the use of hydroxychloroquine prior to systemic chemotherapy to maximize its tumoricidal effect for patients with malignant gliomas.

• Child Health Nursing Research
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• v.16 no.3
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• pp.203-210
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• 2010

Purpose: This study was done to identify cell phone addiction in high school students and variables predicting this addiction. Methods: The participants were 469 adolescents from four high schools. Data were collected through self-report questionnaires, and analyzed using the SPSS program. Results: Of the high school students, 88.4% reported being average users, 7.5%, heavy users, and 4.1%, cell phone addicted. Cell phone addiction was significantly correlated with immediate self-control, self-efficacy, depression, and peer support. Predictors of cell phone addiction were the following: receiving text message on weekends, immediate self-control, main use (text message), minute per call on weekdays, listening to music, gender (female), monthly call charges, depression, person called (friends), and self-efficacy. These factors explained 39% of variance in cell phone addiction. Conclusion: The above findings indicate that cell phone addiction in high school students was influenced by gender, cell phone use, and psychological factors. Therefore the approach to effective cell phone addiction management for high school students is to consider these variables when developing programs for these students.

• Korean Parent-Child Health Journal
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• v.15 no.2
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• pp.60-70
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• 2012

Purpose: This study was done to examine factors influencing cell phone addiction for middle school students by gender. Methods: The participants were 228 male students and 228 female students in two middle schools. Data were collected through self-report questionnaires, and analyzed using the SPSS/WIN 19.0 program. Results: Cell phone addictions of female students are higher than those of male students. Factors influencing cell phone addiction for male students were mimicry, sending text message on weekdays, immediate self-control, grade, syntony, and monthly call charge, explaining 42.2% of variance in cell phone addiction. Factors influencing cell phone addiction for female students were internet addiction, sending and receiving text message on weekends, immediate self-control, long-term self-control, use time, main use, syntony, and monthly call charge, explaining 46.8% of variance in cell phone addiction. Conclusion: The results indicated that cell phone addiction and its influencing factors differed by gender. Therefore the approach to effective cell phone addiction management program for middle school students should consider gender differences.

• Molecules and Cells
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• v.42 no.3
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• pp.189-199
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• 2019

Cell-to-cell variability in gene expression exists even in a homogeneous population of cells. Dissecting such cellular heterogeneity within a biological system is a prerequisite for understanding how a biological system is developed, homeostatically regulated, and responds to external perturbations. Single-cell RNA sequencing (scRNA-seq) allows the quantitative and unbiased characterization of cellular heterogeneity by providing genome-wide molecular profiles from tens of thousands of individual cells. A major question in analyzing scRNA-seq data is how to account for the observed cell-to-cell variability. In this review, we provide an overview of scRNA-seq protocols, computational approaches for dissecting cellular heterogeneity, and future directions of single-cell transcriptomic analysis.

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.3
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• pp.121-134
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• 2006

Purpose : Cuscuta chinensis Lam. is utilized extensively as important medicines for threatened abortion habitual abortion. However, objective data related to an embryo is not existed until now. Therefore, this study is focused to find out stability of Cuscuta chinensis Lam. about an embryo during pregnancy based on data related to stability of nerve cell and antioxydative effect by using neural cell line, PC 12 cell. Methods : Experimentation concerns cytotoxic effects and antioxydative effect through methods such as MTT ssay, western botting after abstracting an undiluted solution from domestic Cuscuta chinensis Lam. Results : 1. As a result of experimentation on MTT assay according to each magnification from Cuscuta chinensis Lam. extraction solution with different abstraction methods, cytotoxic effect is not observed to all extract except an undiluted solution which is abstracted from MeOH stiring. Also, an undiluted solution in stiring with MeOH could not confirm whether come from Cuscuta chinensis Lam. or not. 2. As a result of revelation of Bax and GSK-3${\beta}$ which is responsive to the first stage from general stress in order to observe antioxydative effects of Cuscuta chinensis Lam. revelation of Bax by Cuscuta chinensis Lam. appeared to decrease. Conclusion : Cytotoxic effects with Cuscuta chinensis Lam. about PC12 cell is not discovered and it assume that it would be anti apoptotic effect by ROS as Bax and GSK-3${\beta}$ inviable effect. In the future, this study could be used as basic data for additional research on Cuscuta chinensis Lam. and effect and stability of complicated prescriptions for keeping pregnancy.

• Korean Journal of Clinical Pharmacy
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• v.28 no.1
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• pp.24-29
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• 2018

Background: Cyclosporine is an immunosuppressive agent used to treat and prevent graft versus host reaction (GVHR)-a complication associated with stem cell transplantation. This study aimed to develop a population pharmacokinetic model of cyclosporine and investigate factors affecting cyclosporine clearance in pediatric hematopoietic stem cell transplant patients. Methods: A total of 650 cyclosporine concentrations recorded in 65 patients who underwent hematopoietic stem cell transplantation were used. Data including age, sex, weight, height, body surface area (BSA), type of disease, chemotherapy before stem cell transplantation, type of donor, serum creatinine levels, total bilirubin concentration, hematocrit value, and type of concomitant anti-fungal agents and methylprednisolone used were retrospectively collected. Data related to cyclosporine dosage, administration time, and blood concentration were also collected. All data were analyzed using the non-linear mixed effect model; a two-compartment model with first-order elimination was used. Results: The population pharmacokinetic model of cyclosporine using the NONMEM program was as follows: $CL(L/h)=5.9{\times}(BSA/1.2)^{0.9}$, V2 (L) = 54.5, Q (L/h) = 3.5, V3 (L) = 1080.0, $k_a(h^{-1})=0.000377$. BSA was selected as a covariate of cyclosporine clearance, which increased with an increase in BSA. Conclusion: A population pharmacokinetic model for Korean pediatric hematopoietic stem cell transplant patients was developed, and the important factor affecting cyclosporine clearance was found to be BSA. The model might contribute to the development of the most appropriate dosing regimen for cyclosporine. Further studies on population pharmacokinetics should be carried out, prospectively targeting pediatric patients.

• Journal of Pharmacopuncture
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• v.17 no.1
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• pp.20-26
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• 2014

Objectives: The study aimed to determine changes in laboratory data for cancer patients receiving Korean medicine (KM) care, with a focus on patients' functional status, cancer-coagulation factors and cancer immunity. Methods: We conducted an observational study of various cancer patients in all stages admitted to the East-West Cancer Center (EWCC), Dunsan Korean Hospital of Daejeon University, from Mar. 2011 to Aug. 2011. All patients were under the center's multi-modality Korean-medicine-based inpatient cancer care program. The hospitalization stay at EWCC ranged from 9 to 34 days. A total of 80 patients were followed in their routine hematologic laboratory screenings performed before and after hospitalization. Patients were divided into three groups depending on the status of their treatment: prevention of recurrence and metastasis group, KM treatment only group, and combination of conventional and KM treatment group. The lab reports included natural killer cell count (CD16 + CD56), fibrinogen, white blood cell (WBC), lymphocytes, monocytes, neutrophil, red blood cell (RBC), hemoglobin, platelet, Erythrocyte Sedimentation Rate (ESR), and Eastern Cooperative Oncology Group (ECOG) performance status. Results: With a Focus on patients' functional status, cancer-coagulation factors and cancer immunity, emphasis was placed on the NK cell count, fibrinogen count, and ECOG scores. Data generally revealed decreased fibrinogen count, fluctuating NK cell count and decreased ECOG, meaning improved performance status in all groups. The KM treatment only group showed the largest decrease in mean fibrinogen count and the largest increase in mean NK cell count. However, the group's ECOG score showed the smallest decrease, which may be due to the concentration of late-cancer-stage patients in that particular group. Conclusions: Multi-modality KM inpatient care may have positive effect on lowering the cancer coagulation factor fibrinogen, but its correlation with the change in the NK cell count is not clear.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.4
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• pp.258-263
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• 2010

A numerical stack model has been developed to predict the temperature at a constant-load operation of molten carbonate fuel cell stacks. For the validity of the model, the simulated results with several boundary conditions were compared in the cell temperature data obtained from 75 kW class MCFC stack operation. It was shown that the simulated results with the existing boundary condition, which the stack outlet temperature was fixed at $650^{\circ}C$, didn't match well with the measured data. On the other hand, the stack model with the outlet temperature modified by the outlet manifold temperature measured from the stack under several electric loads was found to explain the measured cell temperature distribution well. The results show that the model can be used to predict the cell temperature distribution in the stacks by the measurement of the manifold outlet temperature.

• ALGAE
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• v.26 no.2
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• pp.201-208
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• 2011

A monoterpene lactone, loliolide was successively isolated from brown seaweed, Sargassum ringgoldianum subsp. coreanum using column chromatography and high-performance liquid chromatography. The structure of the isolated compound was determined by comparison of EIMS and NMR spectral data with the previously published data. The antioxidant activities of loliolide were also evaluated by DPPH and $H_2O_2$ radical and intracellular reactive oxygen species scavenging assays, and it showed moderate activities in all antioxidant assays. Furthermore, loliolide was found to exert positive dose-dependent effects in the protective effects against $H_2O_2$-induced cell damage which were determined via MTT, Hoechst staining assays and cell cycle analysis. This is the first study on chemical constituent of this seaweed according to our best knowledge. These results clearly indicated that loliolide isolated from Sargassum ringgoldianum subsp. coreanum can protect the cells against $H_2O_2$-induced cell damage or apoptosis.