• 대한토목학회논문집
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• 제36권2호
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• pp.245-258
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• 2016

본 연구에서는 미 공병단의 내부 침식 평가 도구를 이용하여 서로 다른 결함 이력을 가진 국내 3개소의 필댐에 대해 내부 침식에 의한 지반공학적 파괴 시나리오의 시스템 응답 확률을 분석하였다. 분석된 확률을 국외 사례에서 조사된 시스템 응답 확률의 범위 및 국내 댐의 과거 사고 통계와 비교 분석하였다. 연구 대상 댐에서 구조물 인접부의 내부 침식 파괴에 대한 시스템 응답 확률은 최대 $10^{-5}$ 수준으로 다른 파괴 시나리오에 대한 값보다 상대적으로 매우 높게 평가되었으며, 실제 국내에서도 구조물 인접부에서 가장 빈번하게 내부 침식 사고가 발생하였다. 하지만 국외에서는 빈번하게 발생하는 기초 지반을 통한 내부 침식과 관련된 파괴 시나리오의 지반공학적 시스템 응답 확률은 상당히 낮은 수준의 $10^{-7}$으로 평가되었다. 이는 실제 국내에서 기초 지반을 통한 내부 침식으로 인해 발생한 댐 파괴 사례가 거의 전무하다는 사실과 유사한 결과이다.

• Clinical and Experimental Pediatrics
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• 제57권1호
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• pp.50-53
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• 2014

Hemophagocytic lymphohistiocytosis (HLH) occurs in the primary form (genetic or familial) or secondary form (acquired). The familial form of HLH (FHL) is a potentially fatal autosomal recessive disorder that occurs because of constitutional defects in cell-mediated cytotoxicity. Here, we report a fatal neonatal case of type 2 FHL (FHL2) that involved a novel frameshift mutation. Clinically, the newborn presented with severe sepsis-like features and required mechanical ventilation and continuous venovenous hemodiafiltration. Flow cytometry analysis showed marked HLH and complete absence of intracytoplasmic perforin expression in cytotoxic cells; therefore, we performed molecular genetic analyses for PRF1 mutations, which showed that the patient had a compound heterozygous mutation in PRF1, that is, c.65delC ($p.Pro22Argfs^*2$) and c.1090_1091delCT ($p.Leu364Glufs^*93$). Clinical and genetic assessments for FHL are required for neonates with refractory fever and progressive multiple organ failure, particularly when there is no evidence of microbiological or metabolic cause.

• Clinical and Experimental Pediatrics
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• 제59권sup1호
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• pp.49-52
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• 2016

X-linked agammaglobulinemia (XLA) is a hereditary humoral immunodeficiency that results from Bruton's tyrosine kinase (BTK ) gene mutations. These mutations cause defects in B-cell development, resulting in the virtual absence of these lymphocytes from the peripheral circulation. Consequently, this absence leads to a profound deficiency of lg all isotypes, and an increased susceptibility to encapsulated bacterial infections. A 15-month-old Korean boy presented with recurrent sinusitis and otitis media after 6 months of age, and had a family history of 2 maternal uncles with XLA. Laboratory tests revealed a profound deficiency of Ig isotypes, and a decreased count of $CD19^+$ B cells in the peripheral circulation. Based on his family history and our laboratory test results, he was diagnosed with XLA. We performed BTK gene analysis of peripheral blood samples obtained from family members to confirm the diagnosis. Mutational analysis revealed a novel hemizygous frameshift mutation (c.82delC, p.Arg28Alafs*5), in the BTK gene. His mother and maternal grandmother were heterozygous carriers of this mutation and his two maternal uncles were hemizygous at the same position. After XLA diagnosis, intravenous immunoglobulin (400 mg/kg, monthly) treatment was initiated; recurrent sinusitis and otitis media were subsequently brought under control. To our knowledge, this is the first reported case of a Korean pedigree with a novel mutation in the BTK gene.

• Asian-Australasian Journal of Animal Sciences
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• 제30권12호
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• pp.1756-1763
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• 2017

Objective: The study aimed at assessing the effects of frozen storage duration on quality characteristics, lipid oxidation and sensory quality of various horse muscles. Methods: Five representative muscles: longissimus dorsi (LD), gluteus medius (GM), semimembranosus (SM), biceps femoris (BF), and triceps brachii (TB) at 24 h post-mortem obtained from 28-mo-old Jeju female breed horses (n = 8) were used in the present investigation. The muscles were vacuumpackaged and frozen at $-20^{\circ}C$ for 120, 240, and 360 days. All the samples were analyzed for thawing and cooking losses, pH, Warner-Bratzler shear forces (WBSF), color traits, total volatile basic nitrogen (TVBN), thiobarbituric acid reactive substances (TBARS) and sensory traits. The muscle samples analyzed on day 0 of frozen storage (fresh, non-frozen) were used for comparison. Results: Results revealed that thawing and cooking losses significantly (p<0.05) increased in all the muscles after 120 days and then remained unchanged up to 360 days of frozen storage. The TBARS and TVBN contents significantly increased as increasing frozen storage time up to 360 days (p<0.05). While, significant decreases in WBSF values were observed for all the muscles with increased frozen storage time (p<0.05). Frozen storage variously affected the color traits of the muscles for instance; the redness of LD, GM, and BF muscles showed a decreasing tendency during frozen storage while it was not changed in TB and SM muscles. Furthermore, the frozen storage did not produce detrimental effects on sensory quality as it did not cause flavor and juiciness defects whereas it partially improved the tenderness of all the muscles studied. Conclusion: Based on the results obtained from our work, it is concluded that frozen storage could be applied to increase the long-term shelf life of horsemeat while still retaining its sensory quality.

• Pediatric Infection and Vaccine
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• 제27권1호
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• pp.69-76
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• 2020

8세부터 17세까지 4회의 세균성 뇌수막염을 경험하였던 21세 남자에서 세균성 뇌수막염이 재발하였고, 혈액과 뇌척수액에서 group B streptococcus (GBS)가 배양되었다. GBS에 의한 성인 뇌수막염의 사례는 흔하지 않으며, 본 증례 환자의 경우에도 과거 소아청소년시기에 재발했던 뇌수막염의 원인은 Streptococcus pneumoniae였다. 저자들은 세균성 뇌수막염이 재발하는 원인 중 환자의 면역 결핍 여부에 대해서는 검사를 통해 배제하였고, 기존의 여러 연구결과에 비추어보아 첫 발병 시부터 존재했던 두개저 해부학적 이상이 S. pneumoniae에 의한 뇌수막염 재발의 원인이라고 판단하였다. 나아가 성인이 되어 GBS 뇌수막염이 발병한 이유는 GBS 혈청형에 대한 옵소닌 포식항체의 혈청학적 유병률을 조사한 연구에 비추어보아 증례 환자가 GBS Ib에 대한 항체가 음성인 경우라면, 해부학적 결함이 해결되지 않은 상태가 코인두 보균이 침습 감염을 일으킬 수 있는 경로가 되어 발병한 사례라고 생각하였다. 환자는 3주 간 항생제 치료 후 임상 경과가 호전되어 퇴원 후 다른 병원에서 수막종과 동반된 뇌기저부의 뇌척수액 누출을 확진 받고 수술을 받았다. 환자는 앞으로도 세균성 뇌수막염 재발 여부와 후유증으로 치료받고 있는 뇌전증에 대해 지속적인 추적관찰이 필요하다.

• Pediatric Infection and Vaccine
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• 제13권2호
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• pp.180-185
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• 2006

침습적 Pseudomonas 감염은 대개 면역 저하 환자들에서 발생하며, 이는 높은 사망률과 관련이 있다. 그러나 드물게는 면역력이 정상인 숙주에서도 발생할 수 있다. 첫 번째 증례는 괴저성 농창과 Pseudomonas 패혈증이 발생한 5개월 여아이며, 두번째 증례는 9개월 남아에서 지역사회 감염으로 발생한 폐렴과 Pseudomonas 패혈증이다. 두 환아 모두에서 녹농균이 배양검사로 증명되어 감수성 있는 항생제를 사용하였으며, T 림프구, B 림프구, 보체, 식세포 등 면역력에 대한 검사는 모두 정상이었다. 저자들은 이전에 건강했던 영아들에서 발생한 침습성 녹농균 감염증 2례를 경험하였기에 이를 보고하는 바이다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.478-478
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• 2012

Recently, there are many researches in order to increase the deposition rate (D/R) and improve film uniformity and quality in the deposition of microcrystalline silicon thin film. These two factors are the most important issues in the fabrication of the thin film solar cell, and for the purpose of that, several process conditions, including the large area electrode (more than 1.1 X 1.3 (m2)), higher pressure (1 ~ 10 (Torr)), and very high frequency regime (VHF, 40 ~ 100 (MHz)), have been needed. But, in the case of large-area capacitively coupled discharges (CCP) driven at frequencies higher than the usual RF (13.56 (MHz)) frequency, the standing wave and skin effects should be the critical problems for obtaining the good plasma uniformity, and the ion damage on the thin film layer due to the high voltage between the substrate and the bulk plasma might cause the defects which degrade the film quality. In this study, we will propose the new concept of the large-area multi-electrode (a new multi-electrode concept for the large-area plasma source), which consists of a series of electrodes and grounds arranged by turns. The experimental results with this new electrode showed the processing performances of high D/R (1 ~ 2 (nm/sec)), controllable crystallinity (~70% and controllable), and good uniformity (less than 10%) at the conditions of the relatively high frequency of 40 MHz in the large-area electrode of 280 X 540 mm2. And, we also observed the SEM images of the deposited thin film at the conditions of peeling, normal microcrystalline, and powder formation, and discussed the mechanisms of the crystal formation and voids generation in the film in order to try the enhancement of the film quality compared to the cases of normal VHF capacitive discharges. Also, we will discuss the relation between the processing parameters (including gap length between electrode and substrate, operating pressure) and the processing results (D/R and crystallinity) with the process condition map for ${\mu}c$-Si:H formation at a fixed input power and gas flow rate. Finally, we will discuss the potential of the multi-electrode of the 3.5G-class large-area plasma processing (650 X 550 (mm2) to the possibility of the expansion of the new electrode concept to 8G class large-area plasma processing and the additional issues in order to improve the process efficiency.

• 한국재료학회지
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• 제13권6호
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• pp.347-351
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• 2003

II-Ⅵ ZnO compound semiconductor thin films were grown on $\alpha$-Al$_2$O$_3$(0001) single crystal substrate by radical beam assisted molecular beam epitaxy and the optical properties were investigated. Zn(6N) was evaporated using Knudsen cell and O radical was assisted at the partial pressure of 1$\times$10$^{4}$ Torr and radical beam source of 250-450 W RF power. In $\theta$-2$\theta$ x-ray diffraction analysis, ZnO thin film with 500 nm thickness showed only ZnO(0002)and ZnO(0004) peaks is believed to be well grown along c-axis orientation. Photoluminescence (PL) measurement using He-Cd ($\lambda$=325 nm) laser is obtained in the temperature range of 9 K-300 K. At 9 K and 300 K, only near band edge (NBE) is observed and the FWHM's of PL peak of the ZnO deposited at 450 RF power are 45 meV and 145 meV respectively. From no observation of any weak deep level peak even at room temperature PL, the ZnO grains are regarded to contain very low defect density and impurity to cause the deep-level defects. The peak position of free exciton showed slightly red-shift as temperature was increased, and from this result the binding energy of free exciton can be experimentally determined as much as $58\pm$0.5 meV, which is very closed to that of ZnO bulk. By van der Pauw 4-point probe measurement, the grown ZnO is proved to be n-type with the electron concentration($n_{e}$ ) $1.69$\times$10^{18}$$cm^3$, mobility($\mu$) $-12.3\textrm{cm}^2$/Vㆍs, and resistivity($\rho$) 0.30 $\Omega$$\cdot$cm.

• Restorative Dentistry and Endodontics
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• 제23권2호
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• pp.656-669
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• 1998

Hydrogen peroxide at high concentration during walking bleaching may cause damage to the tooth structure and to the surrounding periodontal tissues and may develop external root resorption. Clinically, It is so important to find a method of prevention or minimization of these complications. The efficacy of various chamber-irrigating agents to eliminate residual hydrogen peroxide after walking bleaching was examined and compared with water rinse in this study. Extracted human 46 premolars without any cementoenamel junction defects were treated endodontically and based with IRM to 1 mm below CEJ and totally bleached 3 times for each tooth with 30% hydrogen peroxide and sodium perborate. Upon completion of the 3rd walking bleaching procedure, the cervical portion and pulp chamber of each group of teeth were irrigated with catalase, 70% ethylalcohol, acetone, and distilled water. And then, a radicular hydrogen peroxide penetration was measured with spectrophotometer immediately after each bleaching and following treatment with each chamber-irrigating agents, and the significance of their eliminating efficacy of residual hydrogen peroxide was analyzed by Kruskal-Wallis test. The results were obtained as follows. 1. Cervical root penetration of hydrogen peroxide was increased as the bleaching procedure was repeated(P<.01). 2. The most effective irrigant that removed residual hydrogen peroxide was the catalase, and the least effective one was water rinsing (P<.01).; there was no significant difference between the acetone and ethanol group. 3. The Irrigation with antioxidant enzyme or water-displacement solutions can eliminate residual oxygen radicals from the pulp chamber effectively after walking bleaching. So, these agents can reduce adverse effects such as cervical external resorption and periapical inflammation and prevent residual $O_2$ from impeding composite resin polymerization, thus increase the bonding strength of composite resin. This, in turn reduces microleakage and discoloration of the esthetic restoration, extending its service-life.

• Advances in pediatric surgery
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• 제20권2호
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• pp.38-42
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• 2014

Purpose: Gastroschisis and omphalocele are major anterior abdominal wall defects. The purpose of this study was to analyze the clinical differences and mortalities of gastroschisis and omphalocele in Asan Medical Center. Methods: A retrospective review of the medical records was conducted of 103 cases of gastroschisis and omphalocele from September 1989 to February 2013 in Asan Medical Center in Korea. Results: There were 43 cases (41.7%) of gastroschisis and 60 cases (58.3%) of omphalocele. There was a female predominance in both gastroschisis (60.5%) and omphalocele (58.3%). The average gestational age at delivery was $36.7{\pm}0.4$ weeks for both groups. The mean birth weights were $2,381.9{\pm}80.6g$ for gastroschisis and $2,779.4{\pm}82.8g$ for omphalocele (p=0.001). Mean maternal ages in the gastroschisis and omphalocele groups were $27.5{\pm}0.7$ years and $30.5{\pm}0.7$ years, respectively (p=0.002). Associated malformations were documented in 13 infants (30.2%) with gastroschisis and 46 infants (76.7%) with omphalocele (p<0.001). All of gastroschisis patients except one underwent surgery including 31 primary repairs and 11 staged repairs. Fifty-two infants with omphalocele underwent surgery-primary repair in 41 infants and staged repair in 11 infants. Among 103 cases, 19 cases (18.4%) expired. Mortality rates of gastroschisis and omphalocele were 23.3% (10/43 cases) and 15.0% (9/60 cases), respectively (p=0.287). The main causes of death were abdominal compartment syndrome (6/10 cases) in gastroschisis, respiratory failure (4/9 cases) and discharge against medical advice (4/9 cases) in omphalocele. Conclusion: Gastroschisisis was associated with younger maternal age and lower birth weight than omphalocele. Associated malformations were more common in omphalocele. The mortality rates did not make a statistical significance. This might be the improvement of treatment of cardiac anomalies, because no patient died from cardiac dysfunction in our study. Furthermore, abdominal compartment syndrome might be the main cause of death in gastroschisis.