• Journal of The Korean Astronomical Society
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• v.33 no.2
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• pp.111-121
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• 2000

Many models of globular cluster formation assume the presence of cold dense clouds in early universe. Here we re-examine the Fall & Rees (1985) model for formation of proto-globular cluster clouds (PGCCs) via thermal instabilities in a protogalactic halo. We first argue, based on the previous study of two-dimensional numerical simulations of thermally unstable clouds in a stratified halo of galaxy clusters by Real et al. (1991), that under the protogalactic environments only nonlinear (${\delta}{\ge}1$) density inhomogeneities can condense into PGCCs without being disrupted by the buoyancy-driven dynamical instabilities. We then carry out numerical simulations of the collapse of overdense douds in one-dimensional spherical geometry, including self-gravity and radiative cooling down to T = $10^4$ K. Since imprinting of Jeans mass at $10^4$ K is essential to this model, here we focus on the cases where external UV background radiation prevents the formation of $H_2$ molecules and so prevent the cloud from cooling below $10^4$ K. The quantitative results from these simulations can be summarized as follows: 1) Perturbations smaller than $M_{min}\~(10^{5.6}\;M{\bigodot})(nh/0.05cm^{-3})^{-2}$ cool isobarically, where nh is the unperturbed halo density, while perturbations larger than $M_{min}\~(10^8\;M{\bigodot})(nh/0.05cm^{-3})^{-2}$ cool isochorically and thermal instabilities do not operate. On the other hand, intermediate size perturbations ($M_{min} < M_{pgcc} < M_{max}$) are compressed supersonically, accompanied by strong accretion shocks. 2) For supersonically collapsing clouds, the density compression factor after they cool to $T_c = 10^4$ K range $10^{2.5} - 10^6$, while the isobaric compression factor is only $10^{2.5}$. 3) Isobarically collapsed clouds ($M < M_{min}$) are too small to be gravitationally bound. For supersonically collapsing clouds, however, the Jeans mass can be reduced to as small as $10^{5.5}\;M_{\bigodot}(nh/0.05cm^{-3})^{-1/2}$ at the maximum compression owing to the increased density compression. 4) The density profile of simulated PGCCs can be approximated by a constant core with a halo of $p{\infty} r^{-2}$ rather than a singular isothermal sphere.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.15 no.1
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• pp.29-34
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• 2019

Prader-Willi Syndrome (PWS) is a rare neurologic disorder with a prevalence 1/10,000-30,000. The cause of PWS is an abnormalities of chromosome 15q11.2-q13 which is an imprinting gene. Obesity and hyperphagia are characteristic features on a PWS adult. On the other hand, the birth weight, height and body mass index (BMI) of PWS infants are 15-20% lower than those of normal babies and there is a failure to thrive until 24-month-old. Most of PWS patients are treated under general anesthesia and conscious sedation. This case is a treatment of severe caries in a PWS 46 month-old child without general anesthesia and conscious sedation. He came to the Department of Pediatric Dentistry, Kyung Hee University Dental Hospital at Gangdong, Seoul, Korea with a trauma history. He had a medical history with heart surgery and needed to take antibiotics prophylaxis. The luxated left upper primary tooth were removed and caries treatment were done as an outpatient without general anesthesia, conscious sedation.

• Membrane Journal
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• v.31 no.3
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• pp.219-227
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• 2021

Molecularly imprinted membrane (MIM) is a porous polymer membrane incorporating with the molecular recognizing sites. In this study, the supporting P(AN-co-MA) asymmetric membrane was prepared by nonsolvent induced phase separation (NIPS) method. And then, MIM with lysozyme template sites was prepared using the surface imprinting method on the P(AN-co-MA) asymmetric membrane introducing a photoactive iniferter and then photo-grafting. The P(AN-co-MA) asymmetric membrane was modified with 3-chloropropyltrimethoxysilane and dithiocarbamate as a photoactive iniferter. To prepare a lysozyme imprinted membrane, the modified P(AN-co-MA) membrane was copolymerized with acrylamide as a functional momomer, N,N'-methylene bisacrylamide as a crosslinker and lysozyme as a template in the UV irradiation environment. The lysozyme imprinted MIM was analyzed by using SEM, FT-IR and EDS measurements. Its results confirm that all the P(AN-co-MA) membranes have an asymmetric structure and the iniferter group is successfully introduced on the membrane surface. The process parameters were adjusted to obtain MIM having the excellent lysozyme adsorption. The maximum lysozyme adsorption capacity reaches at 2.7 mg/g, which is 13 times higher than that of the non imprinted membrane (NIM). The permselective membrane filtration experiments of ovalbumin to lysozyme show that the P(AN-co-MA) MIM preferentially bounds a greater amount of lysozyme.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.1
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• pp.8-17
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• 2023

In conventional liquid crystal display(LCD) manufacturing process, Indium Tin Oxide(ITO) as transparent electrode and rubbing process of polyimide as alignment layer are essential process to apply electric field and align liquid crystal molecules. However, there are some limits that deposition of ITO requires high vacuum state, and rubbing process might damage the device with tribolectric discharge. In this paper, we made nanocomposite with PEDOT:PSS and MWNT to replace ITO and constructed alignment layer by nano imprint lithography with nano wrinkle pattern, to replace rubbing process. These replacement made that only one PEDOT:PSS/MWNT film can function as two layers of ITO and polyimide alignment layer, which means simplification of process. Transferred nano wrinkle patterns functioned well as alignment layer, and we found out lowered threshold voltage and shortened response time as MWNT content increase, which is related to increment of electric conductivity of the film. Through this study, it may able to contribute to process simplification, reducing process cost, and suggesting a solution to disadvantage of rubbing process.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.84-84
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• 2003

DNA methylation is involved in epigenetic processes such as X-chromosome inactivation, imprinting and silencing of transposons. DNA methylation is a highly plastic and critical component of mammalian development The DNA methyltransferases (Dnmts) are responsible for the generation of genomic methylation patterns, which lead to transcriptional silencing. The maintenance DNA methyltransferase enzyme, Dnmt 1, and the de novo methyltransferase, Dnmt3a and Dnmt3b, are indispensable for development because mice homozygous for the targeted disruption of any of these genes are not viable. The occurrence of DNA methylation is not random, and it can result in gene silencing The mechanisms underlying these processes are poorly understood. It is well established that DNA methylation and histone deacetylation operate along a common mechanistic pathway to repress transcription through the action of methyl-binding domain proteins (MBDs), which are components of, or recruit, histone deacetylase (HDAC) complexes to methylated DNA. As a basis for future studies on the role of the DNA-methyl-transferase in porcine development, we have isolated and characterized a partial cDNA coding for the porcine Dnmt1. Total RNA of testis, lung and ovary was isolated with TRlzol according to the manufacture's specifications. 5 ug of total RNA was reverse transcribed with Super Script II in the presence of porcine Dnmt 1 specific primers. Standard PCRs were performed in a total volume of 50 ul with cDNA as template. Two DNA fragmenets in different position were produced about 700bp, 1500bp and were cloned into pCR II-TOPO according to the manufacture's specification. Assembly of all sequences resulted in a cDNA from 158bp of 5'to 4861bp of 3'compare with the known human maintenance methyltransferase. Now, we are cloning the unknown Dnmt 1 region by 5'-RACE method and expression of Dnmt 1 in tissues from adult porcine animals.

• Journal of Applied Biological Chemistry
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• v.57 no.3
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• pp.227-234
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• 2014

The anti-inflammatory effect of Sargassum micracanthum water extract (SMWE) was investigated using lipopolysaccharide (LPS)-induced inflammatory response in this study. The murine macrophage cell line RAW 264.7 cells were used and MTT assay was performed to measure the cell proliferation ability. The secretion of nitric oxide (NO), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin-6 (IL-6), and IL-$1{\beta}$ was measured in LPS-induced RAW 264.7 cells by ELISA. The expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and nuclear transcription factor-kappa B p65 protein was studied by immunoblotting. The Balb/c mice were used for an acute toxicity test, and imprinting control region mice were purchased to evaluate a croton oil-induced ear edema. As a result, there was no cytotoxicity in the macrophage proliferation treated with SMWE compared to the control. NO levels decreased with increasing concentration of SMWE and were inhibited over 50%. Moreover, the secretion of IL-6, TNF-${\alpha}$, and IL-$1{\beta}$ was suppressed in a dose-dependent manner, especially, IL-$1{\beta}$ inhibition activity was over 50% at 50 ${mu}g$/mL. The formation of ear edema of mice was reduced at the highest dose tested compared to that in the control. Moreover, in acute toxicity test, no moralities occurred in mice administered 5,000 mg/kg body weight of SMWE over 2 weeks observation period. These results suggested that SMWE may have significant effects on inflammatory factors and be potential anti-inflammatory therapeutic materials.

• Journal of Genetic Medicine
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• v.6 no.1
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• pp.56-61
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• 2009

Purpose: Preeclampsia is a multifactorial disorder with genetic and environmental components. Recently, the STOX1 gene, identified as a candidate gene for preeclampsia in Dutch women, has been shown to be placentally expressed and subject to imprinting with preferential transmission of the maternal allele. The purpose of this study is to investigate whether there is an association between the STOX1 Y153H variation and preeclampsia in Korean pregnant women. Materials and Methods: This study involved 202 preeclamptic and 204 healthy pregnant women who were genotyped for the Y153H variant of the STOX1 gene using a commercially available SNapShot assay kit and an ABI Prism 3730 DNA Analyzer. Results: There were no significant differences in genotype frequencies of the Y153H variant of the STOX1 gene between preeclamptic patients and normal controls (P>0.05). The H allele frequency of the STOX1 Y153H variation was similar in patients with preeclampsia (87.1%) and in normal controls (86.5%). In addition, multiple logistic regression analysis showed that the YH, HH, and YH/HH genotypes were not associated with an increased risk of preeclampsia when compared to the YY genotype. Conclusion: This is the first study to characterize the Y153H variant of the STOX1 gene in Korean patients with preeclampsia. We found no differences in the genotype and allele frequencies between preeclamptic and normal pregnancies. Although limited by a relatively small sample size, our study suggests that the STOX1 Y153H variation is not associated with the development of preeclampsia in Korean pregnant women.

• Progress in Medical Physics
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• v.23 no.4
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• pp.269-278
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• 2012

Aquaplast Thermoplastic (AT) is a tissue-equivalent oral compensator that has been developed to improve dose uniformity at the common boundary and around the treated area during radiotherapy in patients with head and neck cancer. In order to assess the usefulness of AT, the degree of improvement in dose distribution and physical properties were compared to those of oral compensators made using paraffin, alginate, and putty, which are materials conventionally used in dental imprinting. To assess the physical properties, strength evaluations (compression and drop evaluations) and natural deformation evaluations (volume change over time) were performed; a Gafchromic EBT2 film and a glass dosimeter inserted into a developed phantom for dose verification were used to measure the common boundary dose and the beam profile to assess the dose delivery. When the natural deformation of the oral compensators was assessed over a two-month period, alginate exhibited a maximum of 80% change in volume from moisture evaporation, while the remaining tissue-equivalent properties, including those of AT, showed a change in volume that was less than 3%. In a free-fall test at a height of 1.5 m (repeated 5 times as a strength evaluation), paraffin was easily damaged by the impact, but AT exhibited no damage from the fall. In compressive strength testing, AT was not destroyed even at 8 times the force needed for paraffin. In dose verification using a glass dosimeter, the results showed that in a single test, the tissue-equivalent (about 80 Hounsfield Units [HU]) AT delivered about 4.9% lower surface dose in terms of delivery of an output coefficient (monitor unit), which was 4% lower than putty and exhibited a value of about 1,000 HU or higher during a dose delivery of the same formulation. In addition, when the incident direction of the beam was used as a reference, the uniformity of the dose, as assessed from the beam profile at the boundary after passing through the oral compensators, was 11.41, 3.98, and 4.30 for air, AT, and putty, respectively. The AT oral compensator had a higher strength and lower probability of material transformation than the oral compensators conventionally used as a tissue-equivalent material, and a uniform dose distribution was successfully formed at the boundary and surrounding area including the mouth. It was also possible to deliver a uniformly formulated dose and reduce the skin dose delivery.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.21 no.1
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• pp.7-14
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• 2021

Purpose: Pseudohypoparathyroidism (PHP) is caused by genetic and epigenetic alteration in the GNAS locus, and characterized by the resistance to multiple hormones and the Albright's hereditary osteodystrophy (AHO) phenotype. This study investigated the phenotypic characteristics and molecular features of PHP. Methods: Eight patients who diagnosed as PHP were enrolled at Pusan National University Children's hospital and clinical features, biochemical and genetic findings were retrospectively reviewed. Results: Of a total of 8 patients, 5 were diagnosed with PHP1a, and 3 were diagnosed with PHP1b. Patients with PHP1a had three different mutations in the GNAS gene, and patients with PHPIb had imprinting defect in differentially methylated regions (DMRs) of the GNAS locus. Two novel GNAS variants were identified in patients with PHP1a, including c.313-2A>T and c.1094G>A. All patients with PHP1a displayed AHO features; short stature (80%), brachydactyly (80%), a round face (80%), obesity (40%), heterotopic ossification (60%), and intellectual disability (60%), whereas only one patient (33.3%) with PHP1b showed AHO feature such as a round face. When phenotypic features between PHP1a and PHP1b patients were compared, patients with PHP1b showed a tendency of higher current height standard deviation scores (SDS) compared to patients with PHP1a, (-3.2±2.1 vs.-1.1±0.8; P=0.06) Conclusions: This study summarizes the phenotypic and genetic features of the PHP patients. Although we found considerable clinical overlap between PHP1a and PHP1b, further long-term follow-up is needed to evaluate the growth and development of children with PHP, as well as the effects of end-organ resistances to endocrine hormones.

• Journal of Popular Narrative
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• v.25 no.2
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• pp.117-167
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• 2019

The aim of this article is to illuminate the Park Yeol(朴烈)·Kaneko Humiko(金子文子) Case from the perspective of performance, by analyzing newspapers published in Colonial Korea. The Park Yeol·Kaneko Humiko Case include the High Treason Incident(大逆事件) case and the mysterious photo(怪寫眞) case that occurred in Tokyo in Imperial Japan from 1923 to 1926. Even though Park Yeol·Kaneko Humiko were individually imprisoned during this period, they proceeded to act shrewdly and preposterously as performers. First, they made the trial itself into an astonishing case by donning traditional Korean clothes and insisting on using the Korean language in Japanese Imperial Court. Second, they caused the judge in charge to accidentally take the so-called 'mysterious photo,' which later led to the collapse of the Japanese cabinet. The newspapers published in Colonial Korea served as unique stage on which Park Yeol and Kaneko Humiko performed. The newspaper articles reported on the public trials as if it were a drama, describing their clothes, look, and dialogue in public court. The news about them was published not as it occurred but in a plotted sequence because of a press ban, consequentially building suspense among readers. Meanwhile, the Korean newspaper editorials pointed out the injustice of the High Treason Incident, breaking down the Japanese judge's opinion. The Park Yeol·Kaneko Humiko Case was a social drama that revealed the disharmony that led to the breakdown of Taisho Democracy and imprinting national resistance in Japan as well as in Korea.