영동세브란스병원 주산기 사망 1998~2003

조시현 ( Si Hyun Cho ),오자랑 ( Ja Rang Oh ),윤덕경 ( Duk Kyoung Yoon ),채용현 ( Yong Hyun Chae ),이미범 ( Mi Bum Lee ),이경은 ( Kyung Eun Lee ),이혜선 ( Hye Sun Lee ),전영은 ( Young Eun Chun ),황주연 ( Ju Youn Hwang ),김재훈 ( Ja 대한주산의학회 2008 大韓周産醫學會雜誌 Vol.19 No.1

목적: 최근 연도별 태아 빛 신생아의 질적 관리를 평가하고자 주산기 통계를 제공하고, 출생체중, 임신주수, 임신부 연령, 영아의 성, 산전 진찰 횟수와 사망원인별 주산기 사망을 분석하고자 하였다. 방법: 1998년부터 2003년까지 본원에서 출생한 단태아 4910예의 전자의무기록을 검토하였다. 주산기는 WHO정의에 따랐고 임상적 사망원인은 Aberdeen 분류를 기준으로 하였다. 결과: 조(교정) 주산기 사망률은 22.8 (13.4)였다. 임신 중단이나 중중기형아를 제외한 4.862예의 출생아 중 (1) 태아사망이 주산기 사망의 78% (51/65)였다. (2) 신생아(4,811예) 출생체중 1,000 g 미만, 1,000~1,499 g, 1,500~2,499 g의 빈도는 각각 0.3%. 0.7%. 5.6%로 생존율은 각각 73.7%, 86.1%, 99.6%였다. (3) 36주 이하의 조산아 사망은 총 신생아 사망의 약 86%(12/14)를 차지하였다. (4) 35세 이상의 고령 임신부(494예)의 주산기 사망률이 20.2로 다른 연령군의 경우보다 높았으나, 의미 있는 차이는 없었다(p=0.273). (5) 남아(2,616예)와 여아(2,245예)의 주산기 사망 시 성비는 173:100으로 남아의 주산기 사망이 의미 있게 높았다(p=0.03l). (6) 산전진찰 2번 미만의 출생아(204예)의 주산기 사망률이 152.0으로 2회 이상의 경우 7.3 보다 의미 있게 높았다(p<0.00l). 조 주산기 사망 112예의 원인을 보면 기형 31.3% 원인 모르는 미숙아 28.6%, 모성질환 10.7% 순이었다. 결론: 출생아 수가 매년 감소하나, 연도별 주산기 사망의 개선된 변화가 없어 특히 조산, 기형, 모성질환에 대한 주산기 관리가 더욱 요구된다. Objective: The aim of this study was to analyze the perinatal mortality rate (PMR) and to evaluate the risk factors of perinatal deaths such as birth weight, gestational age maternal age, fetal sex, number of antenatal visits, and cause of deaths. Methods: Review of electronic medical records of 4,910 cases of singleton deliveries from 1998 to 2003 at Yongdong Severance Hospital was done. The perinatal period was defined according to the WHO definition and the cause of mortality was determined according to Aberdeen Classification. Results: Crude (corrected) PMR was 22.8 (13.4). Among 4862 deliveries excluding termination of pregnancy and severe congenital anomalies, (1) stillbirths accounted for 78% (51/65) of perinatal deaths. (2) Distribution of neonatal birth weights less than 1,000 g, 1,000~1,499 g, 1,500 g~2,499 g were 0.3%, 0.7%, 5.6% with survival rates of 73.7%, 86.1%, and 99.6% respectively. (3) Deaths of preterm births accounted for 86% (12/14) of total neonatal deaths. (4) PMR of 494 cases of advanced maternal age was higher (20.2) than those of other age groups without statistical significance (p=0.273). (5) PMR of male-to-female ratio was 173:100 with statistical significance (p=0.031). (6) PMR of infants with less than 2 antenatal visits was 152.0, in comparison with the rate (7.3) of infants with more than 2 antenatal visits (P<0.001). Among 112 cases of crude perinatal deaths, the leading causes were congenital anomalies (31.3%), prematurity cause unknown (28.6%), and maternal disease (10.7%). Conclusions: The number of births is decreasing, but no significant decrease of PMR was observed. Therefore, intensive care of preterm infants and congenital anomalous babies should be improved.

Epitaxial growth and structural characterization of transparent conducting ZnO:Al thin film deposited on GaN substrate by rf magnetron sputtering

황재열,조채용,이상아,정세영 한국물리학회 2005 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.47 No.2

Transparent conducting oxide Al-modified (2 wt.%) ZnO (AZO) was deposited on a GaN/Al2O3 substrate by rf magnetron sputtering at a substrate temperature of 400 C. With the help of a small lattice mismatch (about 1.9 %) and structural similarity (hexagon on hexagon epitaxy), the AZO film was epitaxially grown on the GaN substrate. This was investigated by four-circle X-ray diffractometer by using monochromatized Cu K1 radiation. The AZO film was well oriented to the lattice of GaN on the a . b plane. This was confirmed by phi-scan measurements of (103) reflection of the AZO layer and of (103) reflection of the GaN substrate under fixed conditions of = 31.66 (2 = 62.858) and = 32.04 (2 = 63.435), respectively. The AZO film showed smooth surface roughness (Ra: 50 °A) and uniformly distributed grains. To investigate the optical transparency, the transmittance spectrum of the AZO/GaN-stacked film was characterized and showed a high transmittance (over 85 %) in the visible spectral range. The resistivity and carrier concentration of the AZO/GaN film, under varying annealing temperatures, were analyzed by Hall measurement and showed a maximal value of 2.38 × 10.4 ·cm and 2.57 × 1021 cm.3, respectively, for the 400 C-deposited film.

Structural and Photoluminescent Properties of S-doped ZnGa2O4:Mn2+ Thin Film Phosphors Grown on Various Substrates by Pulsed Laser Deposition

배종성,조채용,Jong Pil Kim,정중현,이성수,Ung Chan Choi 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.49 No.III

S-doped ZnGa2O4:Mn2+ thin-film phosphors have been grown on Si (100), Al2O3 (0001), and MgO (100) substrates by using the pulsed laser deposition technique. The structural characterization and luminescent properties of S-doped ZnGa2O4:Mn2+ films, according to oxygen pressures, were investigated. The films grown on substrates have different crystallinity and surface morphology. The photoluminescence (PL) of the films is highly dependent on the deposition conditions and, in particular, the oxygen pressure and the type of substrate. The highest emission intensity was observed with S-doped ZnGa2O4:Mn2+ films grown on MgO (100) substrates, whose brightness was 2.7 and 5.8 times higher than those of the films grown on Al2O3 (0001) and Si (100) substrates, respectively. It is indicated that MgO (100) substrate supports epitaxial growth of S-doped ZnGa2O4:Mn2+ films and larger grain size, due to high crystallinity, than any other substrates.

A biocompatible polymeric scaffold as cell-growth supporting biomaterials Fabrication, characterization and cellular responses

이현욱,조채용,박소영,강윤희 한국고분자학회 2009 한국고분자학회 학술대회 연구논문 초록집 Vol.2009 No.4

Rapid thermal annealing effect of Al-doped ZnO thin films

이원재,정세영,조채용,Kyung-Mok Cho 한국물리학회 2005 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.47 No.2

Al-doped ZnO (AZO) thin films were deposited at 250 C by rf-magnetron sputtering and then annealed by a rapid thermal process under different ambients. The annealing effects on the structural, electrical and optical properties of these AZO films were systematically investigated. It was found that all of the AZO films exhibited a c-axis-preferred orientation perpendicular to the substrate and that their crystallinity was improved with the annealing. A resistivity value of 2.2 × 10.4 ·cm was obtained on as-grown AZO films, and their resistivity continuously increased with increasing annealing temperature. The resistivity of the AZO film annealed in an oxygen ambientwas higher than for that annealed in a vacuum. The optical transmission characteristics of the AZO films showed an 85 90 % optical transmission in the visible range, and the band gap of the film annealed in oxygen was lower than for that annealed in a vacuum.j

Dielectric Properties of Artificially Textured (Ba0.5Sr0.5)TiO3 Thin Film Prepared by Pulsed Laser Deposition

황재열,정세영,조채용,배종성,이상아 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.49 No.III

Metal-ferroelectric-metal (MFM)-structured (Ba0.5Sr0.5)TiO3 (BST) thin films were deposited on a Pt(111)/TiO2/SiO2/Si substrate by pulsed laser deposition. The textures of BST films, such as those with (111), (100), and (110) orientations, were successfully controlled by oxygen partial pressure and laser energy under deposition. In spite of the use of (111)-oriented platinized silicon substrates, highly (100)-textured BST film was formed by control of the oxygen flow rate. Voltagedependent dielectric properties, including dielectric constant (r) and dielectric loss (tan ) of the BST capacitors, were studied by capacitance-voltage (C . V) measurements at room temperature. Tunability and figure of merit related to the texture ratio of BST (100) in BST films are also discussed. The texture-control method of MFM-structured BST film using the pulsed laser deposition technique indicated that such film could be a potential candidate for frequency agile device applications.

Physicochemical and mechanical properties of PCL/TiO₂ nanofibrous scaffold

박소영,이현욱,조채용,강윤희 한국고분자학회 2009 한국고분자학회 학술대회 연구논문 초록집 Vol.2009 No.4

Growth and Magnetic Properties of Ge1-xMnx Single Crystals

김성규,정세영,조채용,Sang Eon Park,조용찬 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.49 No.III

Group IV ferromagnetic semiconductor, Ge1.xMnx large size crystals were grown by the Czochralski method in an Ar ambient. The magnetic atom, Mn, was systematically doped into Ge crystal from x = 0 to x = 0.176 and these compositions precisely were obtained by glow discharge spectroscopy. The increase of Mn concentration brought a new Ge8Mn11 phase in Ge matrix. The magnetizations increase greatly reach a maximum value at x = 0.113. The formation of Ge8Mn11 phase is responsible for a ferromagnetic phase between 150 K and 281 K. Especially, in the ferromagnetic phase, the maximum remanent magnetization at x = 0.113 was 0.483 emu/g, which is larger than other results. This feature can be used for some spin devices, because of a large magnetic moment in a low magnetic field.

Polarization Dependence of the Optical Modal Gain in ZnO

Bumjin Kim,김광석,조채용 한국물리학회 2010 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.56 No.1

The modal gain spectrum due to the electron-hole plasma in ZnO was measured using a variablestripe-length method. A modal gain contour map for energy and stripe length allowed the modal gain saturation to be analyzed in terms of the spectral and the stripe length dependences. The modal gain was observed to be more significant in the TE mode than in the TM mode due to the polarization asymmetry of the wurtzite structure. We also found that the degree of polarization are enhanced as the stripe length increased, despite of modal gain saturation.

Ratio Dependence of the Visible Light Photocatalytic Efficiency for Zn_2Ti_(0.9)Cr_yFe_([0.1]-y)O_4: Cr/Fe (0.02 < y < 0.08) Photocatalyst Synthesized by Using a Solid State Reaction Method

Pramod H. Borse,조채용,K. T. Lim,Y. J. Lee,배종성,정의덕,H. G. Kim 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.1

We synthesized four different photocatalyst systems viz. Zn_2TiO_4, Zn_2Ti_(1-x)Fe_xO_4, Zn_2Ti_(1-x)Cr_xO_4 (0 ≤ x < 0.8) and Zn_2Ti_(0.9)Cr_yFe_([0.1]-y)O_4 (0.022TiO<SUB>4</SUB> was converted to visible light active material by controlled doping/co-doping of Cr and Fe metal-ions at Ti substitutional site. We investigated their structural, optical and photocatalytic water decomposition property. The co-doping induces strong absorption bands in visible region (at λ~ 480 nm and λ~ 620 nm) in the host band gap. The optimum system of Zn_2Ti_(0.9)Cr_(0.05)Fe_(0.05)O_4 yielded maximum H<SUB>2</SUB> generation. In contrast to the visible light inactivity of Fe and Cr doped Zn_2TiO_4, the H_2 production under visible light irradiation from co-doped samples, increased till the optimum ‘y’ value. Consequently, there exists an optimized co-dopant concentration for efficient photocatalytic hydrogen production under visible light (λ ≥ 420 nm).