• Journal of Korean Neurosurgical Society
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• v.63 no.3
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• pp.338-341
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• 2020

Cases of syringomyelia associated with spinal dysraphism are distinct from those associated with hindbrain herniation or arachnoiditis in terms of the suspected pathogenetic mechanism. The symptoms of terminal syringomyelia are difficult to differentiate from the symptoms caused by spinal dysraphism. Nonetheless, syringomyelia has important clinical implications, as it is an important sign of cord tethering. The postoperative assessment of syringomyelia should be performed with caution.

• 대한생식의학회:학술대회논문집
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• 2004.06a
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• pp.60.1-60.1
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• 2004

• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.5
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• pp.383-392
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• 2007

In this paper, we study the prediction of depth and width of a defect in steam generator tube in nuclear power plant using neural network. To this end, we first generate eddy current testing (ECT) signals for 4 defect patterns of SG tube: I-In type, I-Out type, V-In type, and V-Out type. In particular, we generate 400 ECT signals for various widths and depths for each defect type by the numerical analysis program based on finite element modeling. From those generated ECT signals, we extract new feature vectors for the prediction of defect size, which include the angle between the two points where the maximum impedance and half the maximum impedance are achieved. Using the extracted feature vector, multi-layer perceptron with one hidden layer is used to predict the size of defects. Through the computer simulation study, it is shown that the proposed method achieves decent prediction performance in terms of maximum error and mean absolute percentage error (MAPE).

• Journal of the Korean Society for Nondestructive Testing
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• v.29 no.1
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• pp.27-35
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• 2009

In this paper, we study the classification of steam generator tube defects using an improved feature extraction. We consider 4 axisymmetric defect patterns of tube: I-In type, I-Out type, V-In type, and V-Out type. Through numerical analysis program based on finite element modeling, 400 ECT signals are generated by varying width and depth of each defect type. From those generated ECT signals, we propose new feature vectors that include an angle between the two points where the Maximum impedance and half the Maximum impedance, and angles between Maximum impedance point and 10%, 20%, 30%, 40% of Maximum impedance points. Also, multi-layer perceptron with one hidden layer is used to classify the defect patterns. Through the computer simulation study, it is shown that the proposed method achieves an improved defect classification performance in terms of Maximum Error and mean square Error.

• Women's Health Nursing
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• v.29 no.4
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• pp.291-301
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• 2023

Purpose: This study aimed to investigate the current status of effective folic acid intake and the level of folic acid knowledge of Chinese pregnant women and to analyze the relationship between effective folic acid intake and folic acid knowledge. Methods: From November 2021 to May 2022, 140 pregnant women at Yantai Yuhuangding Hospital in the Chinese province of Shandong, answered questions about their general characteristics, folic acid intake, and folic acid knowledge. The data were analyzed using the t-test, chi-square test, and logistic regression analysis, and were presented with frequency with percentage or mean±standard deviation. Results: Only 16.4% of the pregnant women (n=23) took folic acid effectively, using the following four criteria. Of all pregnant women who took folic acid, 72.2% took folic acid starting 1 month before pregnancy, 70.8% took folic acid up to 3 months after pregnancy, 36.8% took 400 ㎍ every time, and 78.6% took folic acid more than 24 days every month. The score for folic acid knowledge was relatively high (5.61±2.18 on a scale of 0-9). A higher folic acid knowledge score correlated with more effective folic acid intake (t=4.10, p<.001). Conclusions: Our study shows that the current recommendations to prevent neural tube defects through effective folic acid intake supplementation are not being fully implemented in China. Furthermore, folic acid knowledge was positively correlated with the effectiveness of its intake. Future education related to effective folic acid intake should emphasize the four methods of effective folic acid intake, especially regarding the recommended dose of 400 ㎍ every time.

• Toxicological Research
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• v.17
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• pp.11-16
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• 2001

The development of the central nervous system is a continuous process during the embryonic and fetal periods. For a better understanding of congenital anomalies of central nervous system, three major events of normal development, i.e., neurulation (3 to 4 weeks), brain vesicle formation (4 to 7 weeks) and mantle formation (over 8 weeks) should be kept in mind. The first category of anomalies is neural tube defect. Neural tube defects encompass all the anomalies arise in completion of neurulation. The second category of central nervous system anomalies is disorders of brain vesicle formation. This is anomaly that applies for "the face predicts the brain". Holoprosencephaly covers a spectrum of anomalies of intracranial and midfacial development which result from incomplete development and septation of midline structures within the forebrain or prosencephalon. The last category of central nervous system malformation is disorders involving the process of mantle formation. In the human, neurons are generated in two bursts, the first from 8 to 10 weeks and next from 12 to 14 weeks. By 16 weeks, most of the neurons have been generated and have started their migration into the cortex. Mechanism of migration disorders are multifactorial. Abnormal migration into the cortex, abnormal neurons, faulty neural growth within the cortex, unstable pial-glial border, degeneration of neurons, neural death by exogenous factors are some of the proposed mechanism. Agyria-pachygyria are characterized by a four-layerd cortex. Polymicrogyria is gyri that are too numerous and too small, and is morphologically heterogeneous. Cortical dysplasia is characterized by the presence Q[ abnormal neurons and glia arranged abnormally in focal areas of the cerebral cortex. Neuroglial malformative lesions associated with medically intractable epilepsy are hamartia or hamartoma, focal cortical dysplasia and microdysgenesis.ysgenesis.

• Molecules and Cells
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• v.42 no.8
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• pp.589-596
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• 2019

${\beta}Pix$ is a guanine nucleotide exchange factor for the Rho family small GTPases, Rac1 and Cdc42. It is known to regulate focal adhesion dynamics and cell migration. However, the in vivo role of ${\beta}Pix$ is currently not well understood. Here, we report the production and characterization of ${\beta}Pix$-KO mice. Loss of ${\beta}Pix$ results in embryonic lethality accompanied by abnormal developmental features, such as incomplete neural tube closure, impaired axial rotation, and failure of allantois-chorion fusion. We also generated ${\beta}Pix$-KO mouse embryonic fibroblasts (MEFs) to examine ${\beta}Pix$ function in mouse fibroblasts. ${\beta}Pix$-KO MEFs exhibit decreased Rac1 activity, and defects in cell spreading and platelet-derived growth factor (PDGF)-induced ruffle formation and chemotaxis. The average size of focal adhesions is increased in ${\beta}Pix$-KO MEFs. Interestingly, ${\beta}Pix$-KO MEFs showed increased motility in random migration and rapid wound healing with elevated levels of MLC2 phosphorylation. Taken together, our data demonstrate that ${\beta}Pix$ plays essential roles in early embryonic development, cell spreading, and cell migration in fibroblasts.

• Perinatology
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• v.29 no.4
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• pp.185-188
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• 2018

Jarcho-Levin syndrome is a congenital disorder characterized by several vertebral and costal anomalies. Other abnormalities have also been described, including neural tube defects, Arnold-Chiari malformation, renal/urinary tract abnormalities, hydrocephalus, hydroureteronephrosis, and meningomyelocele. We describe a spondylocostal dysplasia form of Jarcho-Levin syndrome that was prenatally diagnosed at 11 weeks of gestation and surviving. Although the patient had sporadic-type Jarcho-Levin syndrome, with normal karyotype and no family history of disease, the assessment of inheritance patterns and genetic counseling for the parents was important to inform them about the potential risks.

• Nutrition Research and Practice
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• v.12 no.1
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• pp.78-84
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• 2018

BACKGROUND/OBJECTIVES: Folic acid supplementation before pregnancy is known to reduce the risk of neural tube defects. The purposes of this study were to investigate the awareness, knowledge, and use of folic acid supplements along with their associated factors among non-pregnant Korean women of childbearing age. SUBJECTS/METHODS: From August 2012 to March 2013, 704 women aged 19-45 years completed a self-administered questionnaire regarding their awareness, knowledge, and use of folic acid as well as questions to identify risk of inadequate folate intake. RESULTS: Approximately 67% of women reported that they had heard of folic acid, and 23.7% had knowledge of both the role of folic acid in preventing birth defects and appropriate time for taking folic acid supplements to prevent birth defects. However, only 9.4% of women took folic acid supplements at the time of the survey. Women aged 19-24 years, unmarried women, and women who had never been pregnant were less likely to be aware and knowledgeable of folic acid or take folic acid supplements. In addition, women at high risk of inadequate folate intake were less likely to take folic acid supplements. In a multivariate analysis, women aged 19-24 years, women with a high school diploma or lower education level, and unmarried women were less likely to be aware and have knowledge of folic acid. The percentage of women taking folic acid supplements was significantly higher among knowledgeable women than among unknowledgeable women. CONCLUSIONS: These results support our hypothesis that women with knowledge of folic acid are more likely to take folic acid supplements. Therefore, educational programs or campaigns to improve knowledge regarding the importance of folic acid and to promote consumption of folic acid supplements as well as folate-rich foods are needed to target young, less educated, and unmarried women.

• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.1
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• pp.13-19
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• 2010

In this paper, we study a new estimation system for the prediction of steam generator tube defects. In the previous research works, defect size estimators were independently designed for each defect types in order to estimate the defect size. As a result, the structure of estimation system is rather complex and the estimation performance gets worse if the classification performance is degraded for some reason. This paper studies a new estimation system that does not require the classification of defect types. Although the previous works are expected to achieve much better estimation performance than the proposed system since it uses the estimator specialized in each defect, the performance difference is not so large. Therefore, it is expected that the proposed estimator can be effectively used for the case where the defect type classification is imperfect.