도시의 환원 황 화합물의 이산화황으로의 광화학적 변환

손장호,김기현 한국대기환경학회 2004 한국대기환경학회지 Vol.20 No.5

This study examines the local oxidation chemistry of reduced sulfur compounds (RSC) in the urban air. The chemical conversion of RSC (such as DMS, CS₂, H₂S, DMDS, and CH₃SH) to SO₂ was modeled using a photochemical box model. For our model prediction of the RSC oxidation, measurements were carried out from an urban monitoring station in Seoul (37.6˚N, 127.0˚E), Korea for three separate time periods (Sep. 17~18; Oct 23; and Oct. 27~28, 2003). The results of our measurements indicated that DMS and H₂S were the dominant RSC with their concentrations of 370±140 and 110±60 pptv, respectively. The conversion of DMDS to SO₂ can occur efficiently in comparison to other RSC, but it is not abundant enough to affect their cycles. The overall results of our study indicate that the photochemical conversion of the RSC can contribute < 20% of the observed SO₂.

유전자재조합 인간 골형성단백2 및 생흡수성고분자를 이용한 골형성유도체의 개발

이장희,김각균,안강민,김종원,이종호 大韓顎顔面成形再建外科學會 1999 Maxillofacial Plastic Reconstructive Surgery Vol.21 No.4

We tested the bone regenerating capacity and histologic response of bioresorbable matrix-type implant, which was made with Poly(lactide-co-glycolide)(PLGA) and bone apatite for the carrier of bone morphogenetic protein(BMP). The critical size defect of 8mm in diameter was created at the calvaria of SD rats(n=18), and repaired with polymer implant with 15㎍ of rhBMP-2(n=9) or without it(n=9). At 2 weeks, 1 months after implantation, the animals were sacrified(3 animals at every interval and group) and histologically evaluted. The calvarial defect which was repaired with polymer with BMP healed with newly formed bone about 70% of total defect. But that without BMP showed only 0 to under 30% bony healing. Inflammtory response was absent in both group through the experimental period, but there's marked foreign body giant response though it was a little less significant in polymer with BMP group. As the polymer was resorbed, the space was infiltrated and replaced by fibrovascular tissue, not by bone. In conclusion, our formulation of bioresorbable matrix implant loaded with bone morphogenetic protein works good as a bone regenerating material. However, it is mandatory to devise our system to have better osteoinductive and osteoconductive property, and less mutinucleated giant cell response.

同位元素 質量分析機에 의한 植物體中 ??N 測定法 確立 및 온주밀감의 尿素 葉面吸收量 測定에 관한 연구

유장걸,오상호 濟州大學校 亞熱帶農業硏究所 1998 亞熱帶農業硏究 Vol.15 No.-

ABSTRACT This study was conducted to establish the analytical conditions for determining 15N abundance ratio in plant leaves by the isotope ratio mass spectrometer. Effect of some factors related to the equipment performance such as tin capsule cleaning, ion source tunning, sample size and K-factor for total N analysis by the elemental analyzer were investigated using the standard reagents (urea and acetanilide), and citrus leaves. In addition, urea uptake by citrus leaves was measured with 8 and 20-month old leaves were dipped in 15N labelled urea solution(1.776 atom excess %) mixed with 0.05% surfactant and harvested 1, 2, 3, 10 and 17 days after 15N labelled urea application. 1. The analytical conditions for determining 15N isotope ratio in plant leaves a. N-peak was observed from the blank sample of tin capsule which is not cleaned. However, N-peak disappeared after cleaning tin capsules with acetone. b. K-factor for total N determination by the elemental aniyzer was evaluated in terms of the instrument stability. The result showed that the coefficient of variation for K-factor was low enough to obtain a good reproducibility. c. The optimal amount of standard reagents, (urea and acetanilide) and leaf sample for N analysis was in the range of 1 to 3 mg. d. The optimal N amount for 15N isotope ratio analysis was in the range of 0.359 to 0.424 mg. 2. The urea uptake by citrus leaves a. The amount of N absorbed by citrus leaves was increased by elevating the applied urea concentrations and had a maximum at 0.8-1.2% of urea concentrations. b. N amount contained in the leaves increased until 2 days after foliar application but thereafter decreased because N-translocation to the shoot became much more than N-uptake from leaf surface. c. N absorption by 8-month-old leaves was higher than 20-month-old leaves.

Whole-genomic DNA probe를 이용한 구강 Streptococcus 균종의 식별

이영호,이장희,김각균,최선진 대한구강생물학회 1992 International Journal of Oral Biology Vol.16 No.1

DNA hybridization with whole-genomic DNA probe and restriction pattern analysis were done in search for a useful method for identification of the species of mutans group streptocci. Dot blots of genomic DNA of five strains (serotypes a, b, c and g) of mutans streptococci and on strain of Streptococcus sanguis were hybridized with ^32P-labeled whole-genomic DNA of Streptococcus mutans strain 10449 (serotype c) as a probe. Also, genomic DNAs of each strain were digested with two restriction enzymes (EcoRI and HindIII) and the restriction patterns were compared on 0.7% agarose gel after electrophoresis. Whole-genomic DNA probe of Strep. mutans strain 10449 was able to detect 3ng of homologous DNA per dot and was also able to detect the same amount of genomic DNA of a different strain of the same serotype with about the same intensity as shown on the autoradiogram. Genomic DNAs of differnet serotypes of mutans streptococci and of Strep. sanguis strain MPC1 were hybridized weakly with the probe at 50-100ng per dot. Genomic DNAs of six bacteria of two differnet genera (Bacteroides gingivalis and intermedius) were not hybridized with the probe at any concentration used in experiment. Restriction-digested patterns of genomic DNAs were all different from strain to strain, indicating genomic structures between each serotypes of mutans streptococci.

온주밀감의 수체부위에 따른 질소 함량 및 집적량

강영길,유장걸,오현도,오상호 濟州大學校 亞熱帶農業硏究所 1998 亞熱帶農業硏究 Vol.15 No.-

온주밀감에 있어 질소 시비법 개선의 기초자료로 활용하고자 흑색화산회토에 재식된 8년생 궁천조생 16 그루를 대상으로 수체부위별 건물중, N 함량, N 축적량, 건물중 및 N 축적량의 수체부위별 분포비율 등을 조사·분석한 견과를 요약하면 다음과 같다. 1. 그루당 건물중은 7.2~12.6 kg의 범위에 있었고 평균이 10.3 kg, CV가 16.5%이었다. 수체부위별 평균 건물중 분포비율은 뿌리에 총건물중의 22.6%, 줄기에 38.8%, 잎에 14.9%, 과실에 23.7%가 분포되어 있었다. 그루간 수체부위별 건물중 분포비율의 CV는 잎에서 가장 적었고(7.8%) 근간 및 수간에서 매우 컸다(38.5 및 42.6%). 2. 나무 전체 평균 N 함량은 1.13%이었고 뿌리, 줄기, 잎, 과실의 평균 N 함량은 각각 0.96, 0.75. 2.58, 0.99%이였으며, 세근, 녹지의 N 함량은 각각 1.83, 1.18%로 비교적 많은 편이었다. 수체부위별 N 함량의 CV는 4.3~14.6%로 건물중에 비하여 현저히 낮았고 잎(6.8%), 과육(4.6%), 과피(5.5%)에서 적었으나 녹지에서는 14.6%로 컸다. 3. 그루당 N 축적량은 80~145 9의 범위에 있었고 평균이 116 g이었는데, 뿌리에 N 총축적량의 19.3%, 줄기에 25.9%, 잎에 34.0%, 과실에 20.8%가 분포되어 있었다. 뿌리내 N 축적량의 16.4, 32.6, 51.0%가 각각 근간(stock), 중·대근, 세근에, 줄기내 N 축적량의 12.2, 19.8, 26 2, 41.8%가 각각 수간, 대지, 중지, 녹지에, 과실 N 축적량의 68.5%가 과육에 집적되어 있었다. 그루간 수체부위별 N 축적량의 CV는 수체부위별 건물중 분포비율에서와 대체로 비슷한 경향이었다. Dry weight, N content and accumulation, and the distribution of dry weight and N accumulation in various plant parts of sixteen 8-year old Satsuma mandarin trees (Citrus unshiu Marc. Cv. Miyakawa Wase) grown in volcanic ash soil were determined in December 1997 to obtain some information for improving N fertilization. Dry weight per tree ranged from 7.2 to 12.6 kg and averaged 10.3 kg (CV 16.5%) Roots, stems, leaves and fruits had 22.6, 38.8, 14.9, and 23.7% of total dry weight, respectively. The coefficient of variability for leaf dry weight distribution among 16 trees was least (7.8%) while the CV for stock and trunk dry weights great (38.5 and 42.6%, respectively). Average N content for whole tree, roots, stems, leaves and fruits had 1.13, 0.96, 0.75, 2.58 and 0.99%, respectively. Fine roots and twigs also had higher N content with 1.83 and 1.18%, respectively. The coefficient of variability for N content in the various parts of trees ranged from 4.3 (fruits) to 14.6% (twigs) and was much smaller than the CV for dry weight and N accumulation. Nitrogen accumulation per tree ranged from 80 to 145 g and averaged 116 g. Whole roots, stems, leaves and fruits had 19.3, 25.9, 34.0, and 20.8% of total N accumulation of whole tree, respectively. Stock, medium-big roots, and fine roots had 16.4. 32.6, and 51.0% of total N accumulation in whole roots, respectively, while trunk, big and medium branches, and twigs 12.2, 19.8, 26.2 and 41.8% of N accumulated in whole stems, respectively, and pulp 68.5% of N accumulated in whole fruit. The coefficients of variability for N a cumulation distribution among 16 trees had similar trend with dry weight distribution.

연속측정방법을 이용한 도심권 대기질 내 저농도 황화합물의 관측에 대한 연구

최여진,김기현,오상인,손장호 한국대기환경학회 2004 한국대기환경학회지 Vol.20 No.2

In this study, the concentrations of major reduced sulfur compounds (H₂S, CH₃SH, DMS, and DMDS) were determined from ambient air in a monitoring station located in the mid-eastern area of Seoul. Measurements of sulfur species were conducted by the combination of on-line air sampling, thermal desorption, and capillary GC/PFPD analysis. A total number of 143 hourly samples were collected in the two time periods set between June and July 2003. The mean concentrations of four sulfur species measured in the whole study period were found on the order: DMS (535±183H) > H₂S (47±10) > DMDS (35±22) > CH₃SH (6.19±29.4 pptv). The results of this study show that the concentrations of DMS at the study area are generally higher than those reported previously in the oceanic environments, while those of other sulfur species are not easy to compare with due to the lack of data. The H₂S concentrations were generally higher during the daytime than the nighttime, whereas those of others generally exhibited a reversed diurnal pattern. The overall results of our study suggest that the distribution of major reduced S compounds should be controlled by diverse processes in the urban area.

cDNA array를 이용한 피골세포 분화관련 유전자의 탐색

조영준,이장희,이창섭,이상호 大韓小兒齒科學會 2002 大韓小兒齒科學會誌 Vol.29 No.2

RAW 264.7과 이것이 분화한 파골세포양 세포에서 파골세포 분화관련유전자의 전체적인 유전자 발현을 조사하기 위해 cDNA array 방법을 사용하였다. 1176 cDNA spot grid가 있는 Mouse Atlas cDNA array 결과를 확인하기 위하여 역전사 효소 중합반응 검사를 시행하였다. cDNA array 결과 6개의 유전자가 2.5% 이상 발현이 증가하였으며(PKC beta Ⅱ, POMC, PTEN 등), 16개의 유전자가 2.5%이상 발현이 감소하였다(Osteopontin, Cyclin D1, Cathepsin C, PTMA 등). PKC beta Ⅱ유전자의 역전사-효소 중합 반응 검사 결과 이 유전자를 확인할 수 있었다. 파골세포 분화 결과 RAW 264.7 세포주에 비해 파골세포양 세포에서 PKC beta Ⅱ 유전자가 발현이 많았다. 파골세포 분화 관련 유전자는 RAW 264.7 세포주의 파골세포 분화와 연관을 보였다. To examine the global gene expression of osteoclastogenesis-related genes in RAW 264.7 and its differentiated OCLs through the use of Atlas Mouse cDNA Array 2.1 membranes printed with 1176 well-characterized mouse genes involved in biology. Both samples were screened in parallel using cDNA expression arrays. The array re-sults were additionally validated using RT-PCR. The results of cDNA arrays showed that 6 genes were up-regu-lated >2.5-fold (PKC beta Ⅱ, POMC, PTEN, etc) and 16 genes were down-regulated >2.5-fold (Osteopontin, Cyclin D1, Cathepsin C, PTMA, etc) in both samples at the mRNA level. RT-PCR analysis of PKC beta Ⅱ of these differentially expressed genes gave result consistent with cDNA array findings. The result of osteoclastoge-nesis showed that the PKC beta Ⅱ gene was overexpressed in OCLs compared with RAW264.7 cell line. Osteoclastogenesis-related genes are differentially expressed in RAW264.7 cell line and its differentiated OCLs. its gene overexpression correlates with osteoclast differentiation in RAW264.7 cell line.

Overall Conversion Efficiency for Dimethylsulfide to Sulfur Dioxide in the Marine Boundary Layer-An Overview

Zang-Ho Shon 한국대기환경학회 2002 한국대기환경학회지 Vol.18 No.E2

Evaluation of Methyl lodide(CH₃I) Flux Based on Airborne Field Observations

Zang-Ho Shon 한국대기환경학회 2004 한국대기환경학회지 Vol.20 No.E2

A total of 10 boundary layer sampling events over the Pacific Ocean were analyzed for the purpose of defining the sea-to-air CH₃I flux using a mass balance photochemical model. These events were recorded on the National Center for Atmospheric Research (NCAR) C -130 aircraft as part of the Aerosol Charac-terization Experiment (ACE 1). The latitude range, covered by these events, was 2˚N to 55˚S. The flux ranges were 4 to 33 nmol m^-2 day^-1, with an average value of 11±8 nmol m^-2 day^-1. This study also indicated that the current approach to estimate the flux was not systematically different from the sea-air exchange model.

Characteristics of NO-NO₂ System with Different Chemical Regimes during MIRAGE-Mex Field Campaign

Zang-Ho Shon,Sasha Madronich,Sang-Keun Song 한국대기환경학회 2007 한국대기환경학회 학술대회논문집 Vol.- No.-