• Journal of the Korean Society of Safety
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• v.12 no.3
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• pp.38-44
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• 1997

6063-T5 alloys are tested in laboratory air, water and 3% NaCl solution to investigate the effects of corrosive environment on the retardation behavior through single overload fatigue test. Also, the fatigue crack propagation and the crack closure behavior are studied. The results obtained in this experimental study are summarized as follows. 1) Behaviors of fatigue crack growth retardation are observed in water and 3% NaCl solution as they do in air. The number of delay cycles and the size of affected region by single overload decrease greatly in water and 3% NaCl compared with those in air. 2) In fractographic results, the overload marking by single overload appear remarkably in air, but indistinctly in water and 3% NaCl solution. 3) The effect of crack closure on crack propagation is most remarkable in the beginning of crack propagation. With crack propagation, the crack closure level and its effect decrease greatly.

• Journal of Aerospace System Engineering
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• v.1 no.1
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• pp.45-52
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• 2007

This paper analyzed the extension effects of fatigue life and the application of pre-indentation in aircraft structural material such as aluminum alloys. The test specimen used the thin sheet of aluminum alloy with a single-edged notch. The experiments were conducted after making the pre-crack under a constant amplitude loading. As the fatigue life extension technique, the pre-indentation making an indent on the predicted path of crack propagation was applied. The work presented here discussed about a proper mathematical relation between crack growth rate and the range of stress intensity factor and about the generalization of crack growth mechanism with large retardation effect. A technique to enhance the applicability of pre-indentation if also mentioned.

• Journal of Environmental Science International
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• v.11 no.12
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• pp.1315-1320
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• 2002

Since the enzymatic degradation of microbial poly[(R)-3-hydroxybutyrate-co-3-hydroxyvalerate] (P(3HB-co-3HV)) initially occurs by a surface erosion process, a degradation behavior could be controlled by the change of surface property. In order to control the rate of enzymatic degradation, plasma gas discharge and blending techniques were used to modify the surface of microbial P(3HB-co-3HV). The surface hydrophobic property of P(3HB-co-3HV) film was introduced by CF$_3$H plasma exposure. Also, the addition of small amount of polystyrene as a non-degradable polymer with lower surface energy to P(3HB-co-3HV) has been studied. The enzymatic degradation was carried out at 37 $^{\circ}C$ in 0.1 M potassium phosphate buffer (pH 7.4) in the presence of an extracellular PHB depolymerase purified from Alcaligenes facalis T1. Both results showed the significant retardation of enzymatic erosion due to the hydrophobicity and the enzyme inactivity of the fluorinated- and PS-enriched surface layers.

• BMB Reports
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• v.41 no.5
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• pp.363-368
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• 2008

Two genes of temperate mycobacteriophage L5, namely, gp63 and gp64, were hypothesized to be toxic to M. smegmatis. An identical L5 gp64 ortholog (designated hlg1) was cloned from homoimmune mycobacteriophage L1 and characterized at length here. As expected, hlg1 affected the growth of M. smegmatis when overexpressed from a resident plasmid. HLG1 (the protein encoded by hlg1) in fact caused growth retardation of M. smegmatis and the region encompassing its 57-114 C-terminal amino acid residues was found indispensable for its growthretardation activity. Both nucleic acid and protein biosynthesis were severely impaired in M. smegmatis expressing HLG1. Interestingly, HLG1 also affected E. coli almost similarly. This putative delayed early lipoprotein did not participate in the lytic growth of L1.

• Neonatal Medicine
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• v.28 no.1
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• pp.48-52
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• 2021

Aplasia cutis congenita (ACC) is a rare congenital disorder characterized by skin defects involving the epidermis, dermis, subcutaneous tissue, bone, and sometimes dura. It commonly affects the scalp in approximately 70% of cases, but the neck, trunk, and the extremities can also be affected. ACC can occur either as an isolated condition or associated with other anomalies and congenital syndromes, and it can be acquired either genetically or sporadically. Morbidity and mortality are associated with the defects of skull bone, dura, and other multiple anomalies. We herein report the case of a female infant, with a large scalp defect accompanied by a skull defect noted at birth, who developed mental retardation in the preschool years.

• Journal of Sasang Constitutional Medicine
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• v.20 no.3
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• pp.151-163
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• 2008

1. Objective This study was done to identify the anti-stress effect of Hyeongbangdojeok-san (HDS), Yanggyeoksanhwa-tang(YST) in Soyangin. 2. Methods Experimental animals were composed of YST, HDS+stress groups which were administered each by 200mg/kg, 400mg/kg and the Saline+stress group. On the 1st day, making the rats forced swim and on the 2nd day, applying Forced swimming test to the rats. After FST, the levels of Corticosterone in the blood were measured. For the study of learning retardation, memory ability and anxiety reaction, experimental animals were composed of YST, HDS+restraint stress groups which were administered each by 400mg/kg, no stress group and the Saline+restraint stress group. Restraint stress were applied 2 hours a day for 3 weeks. On the last day of the 3rd week, Elevated Plus Maze(EPM) was applied to the groups and Morris Water Maze(MWM) was applied to the groups for 7 days. 3. Results 1. As the results of measuring FST which reflects depression, the YST+stress group and the HDS+stress group showed significant effect in comparison with the Saline+stress group. The levels of Corticosterone in the blood were decreased only in the 400mg/kg YST+stress group. 2. As the results of measuring how long EPM which reflects anxiety reaction stayed in the open arm, there was the trend which can suppress anxiety reaction in the HDS+restraint stress group bur no statistical significance. But there was any suppression of anxiety reaction in the YST+restraint stress group. 3. According to the result of MWM, the saline+restraint stress group showed the learning retardation which means increased time arriving at goal compared to the normal group at the second and third day of measurement. On the contrary, a learning retardation was significantly decreased in the YST+restraint stress group at the third day of measurement. 4. Among the Probe trial test a memory loss occurred in the saline+restraint stress group, but memory ability was significantly increased in the YST+restraint stress group. 4. Conclusion: As the results above, Soyangin Yanggyeoksanhwa-tang has significant influence to the antidepression effect, the learning retardation, the anxiety reaction and also in the Hormone level. Hyeongbangdojeok-san has significant influence to the antidepression effect, in the Hormone level, bur not to the learning retardation and anxiety reaction. prefer to drink cold water, and who are suffering from chronic gastritis.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.11
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• pp.1495-1503
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• 2009

This experiment was conducted to determine the effect of dietary supplementation with BCAA (branched-chain amino acids: leucine, isoleucine and valine) on improving the growth of rats in a malnutritional IUGR (Intrauterine Growth Retardation) model, which was established by feeding restriction. In the experimental treatment, rats were fed purified diets supplemented with BCAA (mixed) during the whole gestation period, while arginine and alanine supplementation were set as the positive and negative control group, respectively. The results showed that, compared to the effect of alanine, BCAA reversed IUGR by increasing the fetus weights by 18.4% and placental weights by 18.0% while fetal numbers were statistically increased. Analysis of gene and protein expression revealed that BCAA treatment increased embryonic liver IGF-I expression; the uterus expressed higher levels of estrogen receptor-$\alpha$ (ER-$\alpha$) and progesterone receptor (PR), and the placenta expressed higher levels of IGF-II. Amino acid analysis of dam plasma revealed that BCAA supplementation effectively enhanced the plasma BCAA levels caused by the feed restriction. BCAA also enhanced the embryonic liver gluconeogenesis by augmenting the expression of two key enzymes, namely fructose-1,6-biphosphatase (FBP) and phosphoenolpyruvate carboxykinase (PEPCK). In conclusion, supplementation of BCAA increased litter size, embryonic weight and litter embryonic weight by improving the dam uterus and placental functions as well as increasing gluconeogenesis in the embryonic liver, which further provided energy to enhance the embryonic growth.

• Clinical and Experimental Pediatrics
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• v.46 no.6
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• pp.597-601
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• 2003

Trisomy 9 mosaic syndrome is a rarely reported chromosomal abnormality with high incidence of intrauterine growth retardation and perinatal death. Even a baby lives, he has severe mental retardation and significant malformations. The incidence and severity of malformations and mental retardation correlate with the percentage of trisomic cells in the different tissues. The characteristic craniofacial abnormalitis are narrow bifrontal diameter, up-slanted and short palpebral fissures, a prominent nasal bridge with a short root, a prominent lip covering a receding lower lip, low-set, posteriorly rotated, and misshapen ears. Ventricular septal defect is a main cardiac abnormality. Bony hypoplasia and dislocated hips have been frequently reported. Central nervous system, hepatobiliary, gastrointestinal and genitourinary abnormalities also had been reported. The authors report a baby who had characteristic abnormalities of trisomy 9 mosaicism with narrow temples, up-slanted palpebral fissures, a bulbous nose, thin and protruding upper lip, low set and malformed ears, hyperextended wrist and overlapping fingers. Cytogenetic analysis performed to confirm the chromosomal abnormality revealed trisomy 9, low level mosaic type.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.3
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• pp.246-252
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• 2014

$Br{\aa}nemark^{\prime}s$ original protocol required 4 to 6 months for implant osseointegration before placement of the definitive prosthesis. Although this approach gave very predictable results, it had certain drawbacks. The main disadvantages of this approach were prolonged treatment time, two surgical procedures, placement of a removable prosthesis that required modifications during the course of treatment, and a greater number of appointments. Immediate implant loading is a viable treatment method for selected cases. One of the greatest advantages of this method is the virtual surgery, which precedes the actual clinical treatment and eliminates any need for last minute decisions. The actual surgery time is decreased, since all steps are predetermined. These advantages aren't only more useful for normal patients but also for the mental retardation patients whose cooperation is difficult. This article presents a clinical approach made possible due to the guided implant surgery and CAD/CAM technique.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.4 no.1
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• pp.23-29
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• 2004

Cystinosis, an autosomal recessively inherited lysosomal storage disease, results from impaired transport of the amino acid cystine out of cellular lysosomes. The consequent accumulation and crystallization of cystine destroys tissues, causing growth retardation, Fanconi syndrome, renal failure, eye problems, and endocrinopathies. The gene for cystinosis, CTNS, was mapped to chromosome 17p13. The diagnosis of cystinosis is made by measuring the leukocyte cystine content and the presence of typical corneal crystals on slit-lamp examination is also diagnostic. Since treatment with cysteamine has proved extremely effective, early diagnosis and treatment are critical aspects. We experienced a typical case of cystinosis in a 12-year-old boy with growth retardation.