합천호 수질 및 영양단계에 대한 평가

최형섭,조인철,변종환,문병현,허종수 한국환경농학회 2003 한국환경농학회지 Vol.22 No.1

호수 유입 하천인 황강의 1996~2001년 년도별 평균 수질은 COD 3.1~4,2 mg/L, T-N 2.460~3.550 mg/L, T-P 0.111~0.201 mg/L이였다. 호수내의 평균 수질은 COD가 1996년 1.9 mg/L에서 2001년 2.7 mg/L로 매년 조금씩 종가하는 것으로 나타났다. 호수내의 1996~2001년 년도별 평균 T-N 농도는 1.393~l.792 mg/L 이었으며, T-P농도는 0.018~0.023 mg/L 이였다. 식물성 플랑크톤의 발생 정도를 나타내는 Chl-α와 T-N, T-P와의 상관계수는 각각 0,382, 0.372였으며, 또한 수온과 강우량에 대한 상관계수는 각각 0.589, 0,526이였다. 따라서 합천댐의 경우 식물성 플랑크톤의 발생이 T-N, T-P보다 수온 및 강수량과 더 밀접한 관계가 있는 것으로 나타났다. 그리고 호수의 영양단계는 중영양~부영양 단계에 있는 것으로 평가되었다. The yearly average water qualifies of the Whang river, which flows into the Hapcheon lake, were COD 3.1~4.2 mg/L, T-N 2.460~3.550 mg/L, and T-P 0.111~0.201 mg/L during 1996~2001. The yearly average COD concentration of Hapcheon lake was increased from 1.9 mg/L (in 1996) to 2.7 mg/L (in 2000). However, T-N and T-P concentration of Hapcheon lake did not show increasing trend over the 6 year period. During 1996~2001, the yearly average concentrations of T-N, T-P were 1.383?1.792 mg/L, 0.018~0.023 mg/L, respectively. The correlation coefficients between chlorophyll α and T-N, T-P, rainfall intensity, water temperature were 0.382, 0372, 0.589, and 0.526, respectively. Therefore, the rainfall and water temperature appeared to play an important role for the variations of chlorophyll α concentration in the Hapcheon lake. Trophic state of the Hapcheon lake were evaluated to be in the range of mesotrophic to eutrophic.

백서 간세포에서 세포외부 칼슘이온이 아드레날린성 약물에 의한 glycogen phosphorylase 활성도에 미치는 영향

최병주,성재현,김중영 慶北大學校 醫科大學 1991 慶北齒大論文集 Vol.8 No.1

The influence of extracellular calcium ions on adrenergic activation of glycogen phosphorylase was studied in isolated rat hepatocyte. Treatment of isolated hepatocytes with epinephrine, phenylephrine and isoproterenol elicited a dose-dependent increase in stimulation of phosphorylase activity. The time course of the activation of phosphorylase by adrenergic agonists was investigated in hapatocytes incubated either with a physiological concentration of extracellular Ca^2+ (2.6mM) or in a medium containing no added Ca^2+. The basal activity of phosphorylase was decreased by approximately 75% in hepatocytes incubated in the low Ca^2+ medium. The addition of adrenergic agonist caused a rapid increase of phosphorylase in cells incubated in the high or low Ca^2+ medium and enzyme activity decreased gradually after reaching a maximum 5 min after adrenergic agonists addition, and basal activity was not attained over the 10-min period of the time course. The magnitude of the maximal stimulatory effect was significantly decreased by the absence of extracellular Ca^2+. The stimulation of phosphorylase induced by epinephrine in the high or low Ca^2+ medium was no longer apparent after 30 min, but a second addition of epinephrine at this time can restimulate phosphorylase to an extent similar to that of a first addition. The addition of CaCl_2 to cells exposed to epinephrine and phenylephrine for 10 min in a medium having a low extracellular Ca^2+ produced a further increase of phosphorylase activity which was larger than the changes observed upon CaCl_2 addition to untreated cells. In order to obtain more information about the mechanism of Ca^2+ entry across the plasma membrane, we investigated the effects of calcium channel blockers on epienphrine-induced phosphorylase activation. Pretreatment of the diltiazem, verapamil, and nifedipine interfered with the magnitude of the maximal effect mediated by epinephrine; the kinetics of the enzyme activity in nifedipine-treated cells was found to be different from that of other channel blockers. These results suggest that entry of extracellular Ca^2+ into the cell is required in order to obtain a sustained adrenergic stimulation of phosphorylase activity and to supply the intracellular Ca^2+ store. The results also indicate that calcium channel blockers inhibit the transport of Ca^2+ across the plasma membrane through a putative Ca^2+ transporter which differs in nature from potential-operated calcium channels in excitable cells. J. Kyungpook. Nat. Univ. Sch. Dent. Vol.8, No.1, 105∼125, 1991.

안구의 비색소성 모양체 상피에서 발생한 유두상 선암종 -1예 보고-

최현주,최영진,이연수,이은정,강석진,김병기,심상인 대한병리학회 1998 Journal of Pathology and Translational Medicine Vol.32 No.12

ℓ-Carnitine의 金屬錯化合物에 관한 硏究

崔秉箕,金順美,趙顯英 同德女子大學校 1987 同大論叢 Vol.17 No.1

In order to clarify transportation, the mode of action of intracellular ℓ-Carnitine related to the β-oxidation of fatty acid. metal (Cu++, Cd++, Mn++, Mg++, Ni++ And Zn++) coordination complexes of ℓ-Carnitine were studied on acid dissociation, stability constant, thermal stability, and functional radical chelated with metal by means of I.R. spectroscopy, differential thermal analysis and Bjerrum's method. The obtained results are summerized as follows: 1. The acid dissociation constant of ℓ-Carnitine in aqueous solution(μ=0.02) was found to be 6.3×10-5 at 25℃. 2. L-carnitine has formed metal coordination complex with Ni++, Co++, Zn++, Mn++, Mg++ an Cd+. From data calculated p[A-] and n, stability constants (log K₂ and log K₃) are obtainde; Metal Complex Cd Co Mn Mg Ni Zn log K₂ 2.7 - - 3.22 - - log K₃ 3.05 2.84 3.33 3.07 2.85 3.83 3. According to I.R. spectral data, amino and carboxyl groups of ℓ-carnitine are assumed to participate in the complex formation. 4. According to differential thermal analysis, each metal-carnitine coordination complex has been shown Mn>Zn>Cd>Mg>Ni>Co in thermal stability. 5. It is assumed that metal/ligand ratios has 1:3 approximately.

근로자 폐기능검사 현황과 정도관리 요인에 대한 연구

최정근,손미아,김현경,백도명,최병순 大韓産業醫學會 1994 대한직업환경의학회지 Vol.6 No.2

Lung function test can be influenced by technical as well as biological variables, and the quality control of test has been stressed as an important part of lung function test program. This study was done to survey the current status of lung function test program in workers' health examination, and examine the variability of test results when quality control is not achieved. Forty nine Workers' Health Examination Institutes and 7 Pneumoconiosis Referal Centers were surveyed for their current lung function tests, types of spirometers, and performance of technicians. To examine the effect of quality control program of lung function tests on the variability of test results, 118 miners were tested under a quality control guideline and the results were compared to those obtained ignoring 4 major areas of the guideline - spirometer calibration, minimum number of tests per session, suitable prediction equations, and selection process of final results for each tested subject. Among surveyed Institutes and Centers, only 38%(20/53) are performing any calibration of spirometers, and most of those calibrations are done automatically by the machine. All the surveyed Institutes and Centers obtain acceptable tests no more than 2 times. The background of technicians include office workers and nurse aids without an adequate training in pulmonary physiology, and the testing posture and formats vary among Institutes and Centers. When the types of pulmonary dysfunction under the definition of the Ministry of labor were compared between those obtained with and without quality control guidelines, spirometer calibration affected the test results in 6(5.1%) out of 118 subjects. The change in the minimum number of adequate tests from 1 to 3 and more brought changes in 19(16.1%) subjects. The test results of 9(7.6%) subjects differed between two different prediction equations, and the results of 7(5.9%) subjects differed between two different selection process of final results. The current practice of lung function tests of workers needs quality control programs, and the results of this study indicate that the first remedy should be to bring the minimum number of acceptable test to more than 3.

열적 변화를 이용한 실내환경 가스의 분류

최낙진,심창현,송갑득,주병수,이윤수,이상문,이덕동,허증수 한국센서학회 2002 센서학회지 Vol.11 No.5

단일 기판위에 온도측정용 Pt 박막과 Pt 히터 그리고 가스 감지를 위하여 순수한 SnO_2 박막과 Pt가 첨가된 SnO_2박막을 설계하고 제작하였다. 제작된 소자는 실내환경가스인 이산화탄소, 프로판 그리고 부탄의 분류에 응용되었다. 동작 온도를 가변하기 위하여 히터의 입력 전압을 사다리꼴로 인가하면서 SnO_2 감지막의 반응특성과 실내환경가스들에 대한 분류여부를 조사하였다. 감지막 반응특성곡선에서 여러 변수들을 추출한 후 주성분분석(principal component analysis : PCA)을 통하여 가스 분류 특성을 검증하였다. Two SnO_2 based sensing films(pure SnO_2 and SnO_2/Pt) and a Pt thin film for temperature sensor on an alumina substrate were designed and fabricated for classifying the indoor environmental gases. By controlling the heating power in the shape of trapezoid, unique four sensing response curves created from both SnO_2 film and SnO_2/Pt film. Then, various parameters were extracted from sensing response curves and carried out principal component analysis(PCA). The results confirm that a sensor array with the proposed operating mode was extremely effective in classifying indoor environmental gases such as CO_2, C_3H_8, C_4H_10.

한국 연안 퇴적물에서 ^137Cs, ^90Sr 및 Pu 동위원소의 분포

최석원,진현국,김철수,노정환,김창규,노병환 대한방사선 방어학회 2002 방사선방어학회지 Vol.27 No.2

한국 주변 연안 15개 정점의 퇴적물(0∼20 cm)에서 ^137Cs, ^90Sr, ^239+240Pu 의 농도와 농도비를 조사했다. ^137Cs, ^90Sr, ^238Pu 및^239+240Pu의 평균 방사능 농도는 각각 2.24±0.79 Bq·kg^-1-dry, 0.20±0.04 Bq·kg^-1-dry, 0.009±0.005 Bq·kg^-1-dry 및 0.27±0.17 Bq·kg^-1-dry이다. ^137Cs/^90Sr, ^239+240Pu/^137Cs 및 ^238Pu/229+240Pu의 평균 농도 비와 ^239Pu/240의 평균 원자 비는 각각 11.2±2.9, 0.123±0.053, 0.033±0.01 및 0.218±0.036이다. 퇴적물에서 핵종의 농도 범위와 핵종간의 농도 비는 그 동안 주변국가의 퇴적물에서 조사한 값과 비슷하였다. 퇴적물에서 ^137Cs과 ^239+240Pu의 상관계수는 0.80이다. ^137Cs과 SOM, ^239+240Pu과 점토 함량과의 상관계수는 각각 0.69, 0.67 이다. The concentrations and activity ratios of ^137Cs, ^90Sr, ^238Pu and ^239+240Pu in sediment(0∼20 cm) at 15 coastal stations of Korea were determined. The mean concentrations of ^137Cs, ^90Sr, ^238Pu and ^239+240Pu are 2.24±0.79 Bq·kg^-1-dry, 0.20±0.04 Bq·kg^-1-dry, 0.009±0.005 Bq·kg^-1-dry and 0.27±0.17 Bq·kg^-1-dry, respectively. The mean activity ratios of ^137Cs/^90Sr, ^239+240Pu/^137Cs and ^238Pu/^229+240Pu and atomic ratio of ^240Pu/^239Pu are 11.2±2.9, 0.123±0.053 and 0.033±0.017 and 0.218±0.036, respectively. The concentrations and activity ratios in sediment samples are similar to those reported from neighbouring country in the northern hemisphere. The correlation coefficient of ^137Cs and ^239+240Pu is 0.80. The correlation coefficient of ^137Cs and soil organic matter(SOM), and ^239+240Pu and clay content are 0.69 and 0.67, respectively.

Seeds의 Crystallinity가 Cordierite의 상변태에 미치는 영향

최태현,전병세,이성우 慶南大學校 附設 工業技術硏究所 1994 硏究論文集 Vol.12 No.-

고밀도이며 고순도인 cordierite를 제조하기 위하여 solution sol-gel법과 α-cordierite의 seeding을 이용하였다. 시료를 분말과 monolith로 나누어 실험을 행하여 seed의 품질이 cordierite의 μ-type에서 α-type로의 상변태와 밀도에 관해서 각각 어떠한 영향을 미치는가에 대해서 알아보았다. 연구결과, 1000℃에서 합성한 seed용 분말보다 1300℃에서 합성한 seed용 분말이 더 α-cordierite 결정에 접근되어 있었고, 1300℃에서 합성한 seed를 첨가한 분말이 여러 범위의 온도에서 α-cordierite결정으로 가장 잘 발달하였으며, monolith의 경우 역시 1300℃에서 합성한 seed를 첨가한 것이 높은 밀도를 가지는 것으로 나타났다. 그러므로 cordierite의 homogeneity와 밀도는 첨가하는 seed의 crystallinity에 크게 좌우된다고 하겠다. Solution sol-gel(SSG) method and seeding were used to fabricate homogenious α-cordierite with high purity. The cordierite powders prepared by SSG and heat-treating at various temperature ranging 1000-1300℃ were added in the mixed or reacted with solution for seeding. Seed powder synthesized at 1300℃ was well developed to α-cordierite rather than any other seed powders at below 1300℃ and the quantity of α-phase was highest in the powder heat-treated at 1300℃ which had been added by seeding at 1300℃. The densities of all the monoliths were high because of existense of other phases like spinel. Therefore, the homogenity of resultant oxides depends on the crystallinity of seed.

외상성 교합으로 인한 어린이의 치주질환

최병재,고동현,김성오,이제호,손흥규 大韓小兒齒科學會 2004 大韓小兒齒科學會誌 Vol.31 No.3

외상성 교합은 교합력의 결과로서 치주조직에 가해지는 손상이다. 주된 증상은 치아의 동요도이고, 통증, 타진에 민감, 열에 민감한 증상이 동반될 수 있으며 교합력에 의해 치아가 이동을 할 수도 있다. 만성으로 진행시 치아의 과도한 교모가 나타나며 방사선학적으로 치근막 공간의 비후, 치조백선의 비후, 치조골의 방사선 투과성, 치근흡수 등이 나타날 수 있다.외상성 교합은 치주질환의 원인과 관련되어 있다. 증가된 치아동요도를 야기하며 외상성 교합 자체는 치은염과 치주낭을 발생시키지 않으나 국소적 치태와 염증이 존재하고 있는 하에서 골소실, 치주낭이 발생할 수 있다. 치은퇴축은 외상성 반월, 맥콜스 팽윤, 스틸만 균열의 형태로 나타난다. 본 증례는 하악 유견치 부위의 치주질환을 주소로 내원한 5세 남아로서 상하악 유견치의 조기 접촉에 의해 하악 좌우측 유견치의 중증도의 동요도, 교합마모, 치은 퇴축, 치조골 파괴의 증상이 나타났기에 보고하는 바이다. Trauma from occlusion(TFO) is injury to the periodontal tissue as a result of occlusal forces. Mobility is a common clinical sign of occlusal trauma. In acute occlusal trauma, this may be accomanied by pain, tenderness to percussion, thermal sensitivity, and pathologic tooth migration. Chronic occlusal trauma may be marked by excessive wear and gingival recession. Radiographic finding include a widened periodontal ligament space, radiolucence and condensation of the alveolar bone, and root resorption. TFO is related to the pathogenesis of periodontal disease. It can cause increased tooth mobility. TFO itself does not initate or aggravate marginal gingivitis or initiate periodontal pockets. Active trauma can accelerate bone loss, pocket formation and gingival recession depending on the presence of local irritants and inflammation. Gingival recession associated with occlusal forces includes traumatic crescent, McCall's festoon and Stillman's cleft. TFO plays a minor role in the pathogenesis of early to moderate periodontitis. A 5-year-old male visited Yonsei University Pedodontics clinic with a chief complaint about gingival recession. Mobility, excessive wear, gingival recession were detected by clinical exam on the both mandibular deciduous canine. On the radiographic view, vertical alveolar bone loss was observed on both mandibular deciduous canine.

슬관절에 히야루론산 주입후 발생한 활막성 연골종증 : 증례 보고

최의성,김용민,김동수,손현철,박경진,조병기,배승환 충북대학교 의과대학 충북대학교 의학연구소 2009 忠北醫大學術誌 Vol.18 No.2

활막성 연골종증은 비교적 드문 양성 종양으로 관절내 활액막 결체조직의 양성 반응성 이형성에 의해 여러 개의 연골성 결절을 형성하고 이것이 관절내로 유리되어 유리체를 형성하는 질환으로 주로 슬관절에 발생한다. 활막성 연골종증의 정확한 발생 기전은 아직 밝혀지지 않았으나 외상, 감염 등이 원인으로 제시되고 있다. 저자들은 슬관절 내 히야루론산 주입후 발생한 슬관절내 활막성 연골종증을 1 례 경험하였으며, 관절경적 제거술을 통해 만족스런 결과를 얻었다. As a relatively rare benign tumor, synovial chondromatosis forms several cartilaginous nodules by the benign reactive metaplasia of synovial connective tissues within joints, which are loosed into the joints and cause a disease forming loose body mainly in knee joint. Accurate mechanism of synovial chondromatosis has not been clarified yet; however, trauma, infections and others have been suggested as its possible causes. The authors of this study experienced an example of a patient with synovial chondromatosis in knee joint occurred after the injection of hyaluronic acid in the joints and had a satisfactory outcome through the arthroscopic resection.