• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.421-422
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• 2002

The purpose of this paper is to investigate the leakage characteristics of the valve stem in the gasoline engines. Especially, three factors affecting oil leakage are the power cylinder, engine head system, and the positive crankcase ventilation system. Which is the most variables, analysis difficulty is the valve stem seal characteristics. The testing system is used with oil motoring system. The leakage of an engine is analyzed for the cylinder temperature, atmosphere pressure, positive pressure, negative pressure, revolution of the camshaft and the surface roughness of the valve stem.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7491-7496
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• 2015

Background: Biomarkers in breast neoplasms provide invaluable information regarding prognosis and help determining the optimal treatment. We investigated the possible correlation between cancer stem cell (CSC) markers (CD133, and ALDH1) in invasive ductal breast carcinomas with some clinicopathological parameters. Aim: To assess the correlation between expression of cancer stem cell (CSC) markers (CD133, and ALDH1) and clinicopathological parameters of invasive ductal breast carcinomas. Materials and Methods: Immunohistochemical analysis of CD133 and ALDH1 was performed on a series of 120 modified radical mastectomy (MRM) specimens diagnosed as invasive ductal breast carcinoma. Results: Expression of both CD133 and ALDH1 was significantly changed and related to tumor size, tumor stage (TNM), and lymph node metastasis. A negative correlation between CD133 and ALDH1 was found. Conclusions: Detecting the expression of CD133 and ALDH1 in invasive ductal breast carcinomas may be of help in more accurately predicting the aggressive properties and determining the optimal treatment.

• Mass Spectrometry Letters
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• v.7 no.4
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• pp.85-90
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• 2016

Post-translational modifications (PTMs) of proteins regulate self-renewal and differentiation in embryonic stem cells (ESCs). Nitration of tyrosine residues of proteins in ESCs modulates their downstream pathways, which can affect self-renewal and differentiation. However, protein tyrosine nitration (PTN) in ESCs has been rarely studied. We reviewed 23 nitrated sites in stem cell proteins. Functional enrichment analysis showed that these nitrated proteins are involved in signal transduction, cell adhesion and migration, and cell proliferation in ESCs. Comparison between the nitrated and known phosphorylated sites revealed that 7 nitrated sites had overlapping phosphorylated sites, indicating functional links of PTNs to their associated signaling pathways in ESCs. Therefore, nitrated proteome provides a basis for understanding potential roles of PTN in self-renewal and differentiation of ESCs.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.170-177
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• 2000

Sorting cut roses according to quality is very essential to increase the value of the product. Many factors are involved in determining the grade of cut roses: length, thickness, and straightness of stem, color and maturity of bud, and extra. Among these factors, the stem straightness and bud maturity are considered to be difficult to set proper classification criteria. In this study, a prototype machine and an analysis procedure were developed to grade cut roses according to stem straightness and bud maturity by utilizing color image processing and neural network. The test results indicated 15.8% classification error for stem straightness and 10.0% for bud maturity.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.651-652
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• 2006

The choice of suitable hip implant is one of important factors in total hip replacement (THR). In clinical view points, improper adaptation of hip implant might cause abnormal stress distribution to the bone, which can shorten the lifespan of replaced hip implant. Currently, interest in custom-designed hip implants has increased as studies reveals the importance of geometric shape of patient's femur in modeling and designing custom hip implants. In this study, we have developed the custom-designed hip implant models with various sizes in hip implant, and the stress distribution in the bone was analyzed using Finite Elements methods. It was found that minimizing the gap between implant stem and femoral cavity is crucial to minimize stress concentration in the bone.

• Journal of Plant Biology
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• v.12 no.1
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• pp.1-6
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• 1969

General components, free sugars, and free amino acids about Zostera marina which is much distributing and producing along the coastlines of Korea have been separated and identified through Ion exchange resin and Paper chromatography method. So distrigushed are sugars contained that this was quantitated by Bertrand method. 1) The result of the general component analysis of Zostera marina shows that there are much free sugars. 2) According to Bertrand method sugar containment quantitated from terrestrial stem and subterranean stem on Po-hang and Ko-hung areas is much more in terrestrial stem than subterranean stem. 3) Seven kinds of sugars are used in experiments(Table 2) among there glucose, fructose and sucrose which keep the sweetness are very much contained. 4) Shown in Fig. 3 ten kinds of free amino acids inspected from experimental liquid by Paper chromatography are separated, which are known, and one spot which in unknown is additionally separated, and in which four kinds of essential amino acid to nutrient are contained.

• Applied Microscopy
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• v.51
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• pp.19.1-19.7
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• 2021

The main purpose of this paper is the preparation of transmission electron microscopy (TEM) samples from the microsized powders of lithium-ion secondary batteries. To avoid artefacts during TEM sample preparation, the use of ion slicer milling for thinning and maintaining the intrinsic structure is described. Argon-ion milling techniques have been widely examined to make optimal specimens, thereby making TEM analysis more reliable. In the past few years, the correction of spherical aberration (Cs) in scanning transmission electron microscopy (STEM) has been developing rapidly, which results in direct observation at an atomic level resolution not only at a high acceleration voltage but also at a deaccelerated voltage. In particular, low-kV application has markedly increased, which requires a sufficiently transparent specimen without structural distortion during the sample preparation process. In this study, sample preparation for high-resolution STEM observation is accomplished, and investigations on the crystal integrity are carried out by Cs-corrected STEM.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.6
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• pp.539-543
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• 2006

Lodging is classified as root lodging caused by the loss of supporting force in the root, bending caused by the deformation of the stem and breaking where the stem breaks down as loads exceeding critical elasticity were applied. This research excluded breaking which is not in a state of equilibrium and tried to partition the level of lodging using an algebraic model in root lodging and stem lodging, or bending. When a vertical load was applied, the deformation of the stem of rice plant showed the form of a quadratic equation. The trace of the panicle neck in the process of lodging was an ellipse-shape. When loading was pure root lodging, the trace of the panicle neck became a circle of which culm length is the radius. When it was a pure stem lodging, the trace of the panicle neck is an ellipse of which major axis is culm length and minor axis is 0.64* culm length. When both stem lodging and root lodging occurred in a natural setting, the partitioning of lodging can be calculated by a formula using eccentricity of an ellipse, S=e*100/0.768(S is the ratio of stem lodging in the whole lodging, e is eccentricity of the ellipse). This method is expected to be useful in simple lodging partitioning. We could also calculate the partitioning of stem lodging and root lodging as units of angles as an accuracy method, by using a straight line calculated by differentiating a quadratic equation of stem deformation at the origin of the coordinates. These two methods for dividing root and stem lodging showed different values. However, each of them showed almost same values with different lodging degree in one plant.

• International Journal of Stem Cells
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• v.16 no.2
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• pp.215-233
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• 2023

Background and Objectives: MYC, also known as an oncogenic reprogramming factor, is a multifunctional transcription factor that maintains induced pluripotent stem cells (iPSCs). Although MYC is frequently upregulated in various cancers and is correlated with a poor prognosis, MYC is downregulated and correlated with a good prognosis in lung adenocarcinoma. MYC and two other MYC family genes, MYCN and MYCL, have similar structures and could contribute to tumorigenic conversion both in vitro and in vivo. Methods and Results: We systematically investigated whether MYC family genes act as prognostic factors in various human cancers. We first evaluated alterations in the expression of MYC family genes in various cancers using the Oncomine and The Cancer Genome Atlas (TCGA) database and their mutation and copy number alterations using the TCGA database with cBioPortal. Then, we investigated the association between the expression of MYC family genes and the prognosis of cancer patients using various prognosis databases. Multivariate analysis also confirmed that co-expression of MYC/MYCL/MYCN was significantly associated with the prognosis of lung, gastric, liver, and breast cancers. Conclusions: Taken together, our results demonstrate that the MYC family can function not only as an oncogene but also as a tumor suppressor gene in various cancers, which could be used to develop a novel approach to cancer treatment.

• Child Health Nursing Research
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• v.26 no.4
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• pp.402-410
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• 2020

Purpose: This study aimed to determine the level of health-related quality of life (HRQoL) of children and adolescents who received hematopoietic stem cell transplantation (HSCT) and to examine factors influencing HRQoL. Methods: This cross-sectional descriptive study involved 85 participants aged 10 to 19 years who received treatment from 3 months to 5 years after HSCT. Symptom experiences, stress and coping, self-esteem, social support, and HRQoL were measured. Descriptive analysis, the independent t-test, one-way analysis of variance, Pearson correlation analysis, and stepwise multiple regression were used for data analysis. Results: The mean HRQoL score was 72.26 points out of 100. HRQoL showed statistically significant correlations with symptom experiences, stress, self-esteem, social support, satisfaction with peer relationships, and perceived attentiveness of the medical team. The most influential predictors of HRQoL were symptom experiences (β=-.51, p<.001) and satisfaction with peer relationships (β=.32, p<.001). Conclusion: The experiences of different symptoms by children and adolescents who receive HSCT must be considered. In addition, nursing interventions, such as self-help meetings with peer groups, should be provided to improve their HRQoL.