• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.29 no.2
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• pp.507-521
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• 1999

Osteopetrosis is an uncommon hereditary bone disorder whose prominent radiologic feature characterized by increased bone density. The authors reported a 7-year-old male patient who referred from local dental clinic for dental problems such as early exfoliation of deciduous teeth(#54,73,83) and delayed eruption of permanent teeth(#31.41.36.46). The patient appeared as a poorly developed. Dental X-ray films showed early exfoliation of deciduous teeth, delayed eruption of permanent teeth, and rampant caries. Lateral view of skull demonstrated increased opacity of calvarium, facial bones, and skull base. Generally the skeletal density is greatly increased throughout all bones. Facial CT showed poor development of paranasal sinuses and mastoid air cells. No hematopoietic and neurologic complications such as anemia, thrombocytopenia, blindness and deafness were found. Also mental retardation was not found. The final diagnosis of this case was a osteopetrosis tarda. Sometimes patient with osteopetrosis tarda may be developed dental problems prior to severe systemic symptoms. The dentist can be the first clinician to see the patient. It is very important for the dentist to have the knowledge of the osteopetrosis and to care the patient's dental problems to prevent complication such as osteomyelitis of jaws.

• The Korean Journal of Rheology
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• v.11 no.1
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• pp.44-49
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• 1999

Effects of particulate size and frictional characteristics were examined on the melting behavior of PP (polypropylene) in a batch mixer. Powder and pellet types of PP were used and each component was blended with PE (polyethylene) wax and clay, respectively. It was observed that small size particulates, i.e. powder systems exhibit accelerated melting behavior; and it was also found that the abrasive additive acts as an effective agent for fast melting of PP powder. Retardation of melting due to the reduced friction was observed in PP pellet/PE wax blends, while melting rate of PP powder was increased by addition of PE wax.

• Journal of Genetic Medicine
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• v.9 no.2
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• pp.89-92
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• 2012

Campomelic dysplasia (CMD) is a rare, often lethal, genetic disorder characterized by multiple congenital anomalies and abnormal development of the reproductive organs in males. Mutations in the SOX9 gene are known to cause CMD. We present a Korean CMD girl with a normal 46,XX karyotype and a female reproductive organ phenotype. She was born at 2.35 kg at 38 weeks of gestation and showed characteristic phenotypes, including cleft palate, micrognathia, hypertelorism, flat nasal bridge, congenital bowing of limbs, hypoplastic scapulae, deformed pelvis, and 11 pairs of ribs. She also had an atrioseptal defect of the heart and marked laryngotracheomalacia requiring tracheostomy and tracheopexy. SOX9 mutation analysis revealed the presence of a novel nonsense mutation, $p.Gln369^*$, and the patient was genetically confirmed to have CMD. Although she showed marked failure to thrive and neurodevelopmental delay, she is now 40 months of age and is the only surviving patient with CMD in Korea.

• Clinical and Experimental Pediatrics
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• v.55 no.6
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• pp.212-214
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• 2012

Rubinstein-Taybi syndrome (RTS) is characterized by peculiar facies, mental retardation, broad thumbs, and great toes. Approximately one-third of the affected individuals have a variety of congenital heart diseases. They can also have upper airway obstruction during sleep, due to hypotonia and the anatomy of the oropharynx and airway, which make these patients susceptible to obstructive sleep apnea (OSA). In our case, pulmonary hypertension was caused, successively, by congenital heart defects (a large patent ductus arteriosus and arch hypoplasia) and obstructive sleep apnea during early infancy. The congenital heart defects were surgically corrected, but persistent pulmonary hypertension was identified 2 months after the operation. This pulmonary hypertension was due to OSA, and it was relieved by nasal continuous positive airway pressure. This case is the first report of pulmonary hypertension from OSA in a young infant with RTS.

• Journal of Korean Academy of Nursing
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• v.35 no.1
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• pp.5-15
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• 2005

Purpose: This study was conducted to develop a behavioral checklist to predict an autistic disorder and to identify the earliest detecting time. Method: One hundred and fifty eight children including normal, autistic, institutionalized normal, and retarded were assessed using critical interaction behavioral markers from literature review. Data was collected by semi-structured mother-child interaction by videotape recording and analyzed byfactor analysis, Cronbach a, Kappa, $x^2$, and Duncan. Result: Ten behavioral markers were sorted into 2 factors; joint-attention and synchronized behavior. Autistic children were impaired in pretend play, odeclarative pointing, proimperative pointing, gaze-monitoring, referential looking, showing, joint-attention, rhythmical vocal exchange, and synchronized laughing. The sychronized behavior was also a critical marker to predict the autistic disorder. However, it was difficult to differentiate autistic disorder from mental retardation. In addition, the appropriate detecting time was around 18 months after birth. Conclusion: This checklist should be behavior markers to predict autistic disorder and could be useful as educational material at children's clinics, parents class, and for caregivers in the health center. In addition, early detection should lead to treatment being started as soon after 18 months of age as possible.

• Journal of the Korean Chemical Society
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• v.29 no.4
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• pp.419-425
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• 1985

N-Methylamidinoglycine, an isomer of creatine which was postulated to be formed enzymatically in vitro, has been synthesized by coupling glycine with N, S-dimethylthiopseudouronium iodide in a yield of approxirnately 60%. On heating in acidic solution, it was converted to a cyclized form (isocreatinine) in analogy with the conversion of creatine to creatinine(anhydrous form). Structures were confirmed by an elemental analysis and proton NMR spectroscopy. Further studies on their characteristics were compared with those of creatine and creatinine in regard to isoelectric points(pI), retardation coefficients(Rf) on thin layer chromatography, and elution profiles on amino acid analyzer. In order to facilitate the comparison, $^{14}C$-labeled creatine, creatinine, isocreatine and isocreatinine were also synthesized.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.11
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• pp.2383-2389
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• 2002

This paper describes an experimental study on fatigue life extension by using cold working process in fastener hole of aircraft structure. Cold working process was applied for A12024-7351 specimens by considering the effect of edge margin on fatigue life. It is generally recognized that cold working process offers a protective zone around fastener hole of aluminum aircraft structure due to the residual compressive stresses which lead to retardation of crack growth. Thus this process provides the beneficial effect of increasing the fatigue life of the component. there by decreasing maintenance costs. It has also been successfully incorporated into damage tolerance and structural integrity programs. Cold working specimens were tested at constant amplitude peak cyclic stresses. Fatigue life of cold working specimen compared with that of specimen fabricated with base material. The increase of fatigue life for cold working specimen is discussed by both considering the effect of residual compressive stresses measured by X-ray diffraction technique and quantitative effect of edge margin.

• Journal of Genetic Medicine
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• v.4 no.2
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• pp.196-199
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• 2007

Coffin-Lowry syndrome (CLS) is a rare X-linked hereditary disorder characterized by moderate to severe mental retardation, facial dysmorphism, tapering fingers, and skeletal deformity. A 12-month-old boy was referred to our pediatric clinic for his developmental delay and seizure with fever. The boy exhibited a coarse facial appearance characterized by prominent, high-arched eyebrow, broad nose, downward palpebral fissure, high arched palate, hypodontia. The boy also showed finger tapering and puffy hand. Hypotonia, hyperextensible fingers and hypermobility of the joint were seen. Based on these findings, he was diagnosed as having Coffin-Lowry syndrome. We report a case of Coffin-Lowry syndrome with reference.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.12
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• pp.2070-2077
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• 2001

An experimental investigation of the effect of composite patching repair was conducted to characterize the fatigue crack growth behavior in thick A16061-T6 (6mm) panels with single bonded patch by fiber reinforced composite patch. Four patch lengths and no patch plate were examined. An analytical procedure, involving three-dimensional finite element method having three layers to model cracked aluminum plate, epoxy by adhesive and composite Patch, is calculated the stress intensity factors. From the calculated stress intensity factors, the fatigue crack growth rates are obtained. At the single patching type, different fatigue crack growth ratios through the palate thickness were investigated by using the experimental and analytical results. The results demonstrated that there was a definite variation in fatigue life depending on the size of composite patch. While crack reached the patch end, retardation of crack growth was also revealed in the bonded repair.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.421-425
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• 2007

The inhibitory effect of onion extract on polyphenol oxidase (PPO) and browning of peach juice was investigated. Various reducing agents such as L-ascorbic acid, L-cysteine, dithiothreitol, glutathione, and sodium pyrosulfite strongly inhibited polyphenol oxidase extracted from peach. The enzyme was also inhibited by addition of water extract of onion. Regardless of substrates used, the addition of heated onion extract exhibited stronger inhibitory effect on peach polyphenol oxidase activity than that of the fresh one. The inhibitory effect of onion extract was dependent on heating temperature and time. The onion extract inhibited the peach polyphenol oxidase non-competitively. The heating of onion extract in the presence of glucose, glycine stimulated the inhibitory effect of the onion extract, which suggests non-enzymatic browning products produced during heating might be responsible for the stronger inhibitory action of the heated onion extract. The retardation of peach juice browning by onion extract seems to be caused by inhibition of peach PPO.