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Seasonal Variation of Contribution of Leaf-Litter Decomposition Rate in Soil Respiration in Temperate Deciduous Forest (토양호흡의 계절적 변이에 기여하는 리터의 분해속도)

  • Suh Sang-Uk;Min Youn-Kyung;Lee Jae-Seok
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.7 no.1
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    • pp.57-65
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    • 2005
  • In a forest ecosystem, the major source of soil carbon input is from litterfall and its decomposition. To understand the effect of litterfall and litter decomposition on seasonal variation of soil respiration and litter decomposition rates were measured in temperate deciduous forest in Korea. Annual litterfall collected from litter trap (1m x 1m) were 147.5 ± 8.2g Cm/sup -2/ yr/sup -1/ in 2003. About 47% of litterfall were Quercus serrata leaf followed by Carpinus laxiflora leaf (27 %), Carpinus cordata leaf (7 %), and others, such as other leaf, bark, branch, and acorn, were 20%. The decomposition rate was the highest in C. cordata (33.03%, k = 0.46), followed by C. laxiflora (25.73%, k = 0.30), and Q. serrata (24.17%, k = 0.28). The continuous measurement of soil respiration from January 2004 to December 2004 was carried out using AOCC (Automatic Open-Closed multi-Chamber system). The annual soil respiration rate was 629.6g Cm/sup -2/ yr/sup -1/ and the litter decomposition was 30.0g Cm/sup -2/ yr/sup -1/. The portion of litter decomposition rate on soil respiration rate was about 5%. From January to February, when the soil respiration rate was the lowest, about 11 % of soil respiration (7.4 ± l.4g Cm/sup -2/ month/sup -1/) were effected by litter decomposition rate (0.8g Cm/sup -2/ month/sup -1/). The highest soil respiration rate (111.5 ± 16.2g Cm/sup -2/ month/sup -1/) and litter decomposition rate (11.4g Cm/sup -2/ month/sup -1/) were showed in July to August. According to the regression analysis between soil respiration rate and litter decomposition, the soil respiration rate were related to litter decomposition with the correlations (r = 0.63).

Ultrastructural analysis and quantification of autophagic vacuoles in wild-type and atg5 knockout mouse embryonic fibroblast cells (정상 및 atg5 유전자 제거 섬유아세포에서 자가포식체의 미세구조 및 이들의 정량적 분석)

  • Choi, Suin;Jeon, Pureum;Huh, Yang Hoon;Lee, Jin-A
    • Analytical Science and Technology
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    • v.31 no.5
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    • pp.208-218
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    • 2018
  • Autophagy is a cellular process whereby cytosolic materials or organelles are taken up in a double-membrane vesicle structure known as an autophagosome and transported into a lysosome for degradation. Although autophagy has been studied at the genetic, cellular, or biochemical level, systematic ultrastructural quantitative analysis of autophagosomes during the autophagy process by using transmission electron microscopy (TEM) has not yet been reported. In this study, we performed ultrastructural analysis of autophagosomes in wild-type (WT) mouse embryonic fibroblasts (MEFs) and autophagy essential gene (atg5) knockout (KO) MEFs. First, we performed ultrastructural analysis of autophagosomes in WT MEFs compared to atg5 KO MEFs in basal autophagy or starvation-induced autophagy. Although we observed phagopore, early, late autophagosomes, or autolysosomes in WT MEFs, atg5 KO MEFs had immature autophagosomes that showed incomplete closure. Upon starvation, late autophagosomes accumulated in WT MEFs while the number of immature autophagosomes significantly increased in atg5 KO MEF indicating that atg5 plays an important role in the maturation of autophagosomes. Next, we examined autophagosomes in the cell model expressing polyQ-expanded N-terminal fragment of huntingtin. Our TEM analysis indicates that the number of late autophagosomes was significantly increased in the cells expressing the mutant huntingtin, indicating that improving the fusion of autophagosome with lysosome may be effective to enhance autophagy for the treatment of Huntington's disease. Taken together, the results of our study indicate that ultrastructural and quantitative analysis of autophagosomes using TEM can be applied to various human cellular disease models, and that they will provide an important insight for cellular pathogenesis of human diseases associated with autophagy.

Usefulness assessment of secondary shield for the lens exposure dose reduction during radiation treatment of peripheral orbit (안와 주변 방사선 치료 시 수정체 피폭선량 감소를 위한 2차 차폐의 유용성 평가)

  • Kwak, Yong Kuk;Hong, Sun Gi;Ha, Min Yong;Park, Jang Pil;Yoo, Sook Hyun;Cho, Woong
    • The Journal of Korean Society for Radiation Therapy
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    • v.27 no.1
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    • pp.87-95
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    • 2015
  • Purpose : This study presents the usefulness assessment of secondary shield for the lens exposure dose reduction during radiation treatment of peripheral orbit. Materials and Methods : We accomplished IMRT treatment plan similar with a real one through the computed treatment planning system after CT simulation using human phantom. For the secondary shield, we used Pb plate (thickness 3mm, diameter 25mm) and 3 mm tungsten eye-shield block. And we compared lens dose using OSLD between on TPS and on simulation. Also, we irradiated 200 MU(6 MV, SPD(Source to Phantom Distance)=100 cm, $F{\cdot}S\;5{\times}5cm$) on a 5cm acrylic phantom using the secondary shielding material of same condition, 3mm Pb and tungsten eye-shield block. And we carried out the same experiment using 8cm Pb block to limit effect of leakage & transmitted radiation out of irradiation field. We attached OSLD with a 1cm away from the field at the side of phantom and applied a 3mm bolus equivalent to the thickness of eyelid. Results : Using human phantom, the Lens dose on IMRT treatment plan is 315.9cGy and the real measurement value is 216.7cGy. And after secondary shield using 3mm Pb plate and tungsten eye-shield block, each lens dose is 234.3, 224.1 cGy. The result of a experiment using acrylic phantom, each value is 5.24, 5.42 and 5.39 cGy in case of no block, 3mm Pb plate and tungsten eye-shield block. Applying O.S.B out of the field, each value is 1.79, 2.00 and 2.02 cGy in case of no block, 3mm Pb plate and tungsten eye-shield block. Conclusion : When secondary shielding material is used to protect critical organ while irradiating photon, high atomic number material (like metal) that is near by critical organ can be cause of dose increase according to treatment region and beam direction because head leakage and collimator & MLC transmitted radiation are exist even if it's out of the field. The attempt of secondary shield for the decrease of exposure dose was meaningful, but untested attempt can have a reverse effect. So, a preliminary inspection through Q.A must be necessary.

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Sex Differences in the Pain Control by the Peripheral Opioid (성별에 따른 말초 opioid의 통증조절)

  • Bae, Sung-Jae;Kim, Wan-Su;Kang, Soo-Kyung;Auh, Q-Schick;Hong, Jung-Pyo;Chun, Yang-Hyun
    • Journal of Oral Medicine and Pain
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    • v.38 no.4
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    • pp.339-356
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    • 2013
  • This study was designed to evaluate the sex differences in the pain control effect by morphine injection to masticatory muscle pain patients. Patients with masticatory muscle pain visited the Department of Oral Medicine, Kyung Hee University Dental Hospital were recruited to this study and diagnosed by RDC/TMD. Experimental group were divided into four group each from male (n=20) and female (n=20); saline injection group (n=5), lidocaine injection group (n=5), morphine 1.5 mg injection group (n=5) and morphine 3 mg injection group (n=5). Evaluation list was the subjective pain evaluation(visual analogue scale, Mc Gill pain questionnaire, pain drawing) and the objective pain evaluation(pressure pain threshold, pressure pain tolerance) and evaluation time was injection before, after 1 hour, 24 hour, 48 hour and then it was analyzed statistically. The results were as follows : 1. The male and female were significantly different statistically morphine 3 mg group in visual analogue scale evaluation. (male: p<0.05, female: p<0.05) 2. The male and female were more significantly different statistically morphine 3 mg group than morphine 1.5 mg group in McGill pain questionnaire evaluation. (male: p<0.001, female: p<0.01) 3. The male were significantly different statistically morphine 3 mg group in pain drawing evaluation and pressure pain threshold evaluation. (PD: p<0.001, PPT: p<0.05) Therefore, it was revealed that the morphine 3 mg injection for masticatory muscle pain was effective to pain control male patients and more effect than female patients in the objective pain evaluation.

Velocity-effective stress response of $CO_2$-saturated sandstones ($CO_2$로 포화된 사암의 속도-유효응력 반응)

  • Siggins, Anthony F.
    • Geophysics and Geophysical Exploration
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    • v.9 no.1
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    • pp.60-66
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    • 2006
  • Three differing sandstones, two synthetic and one field sample, have been tested ultrasonically under a range of confining pressures and pore pressures representative of in-situ reservoir pressures. These sandstones include: a synthetic sandstone with calcite intergranular cement produced using the CSIRO Calcite In-situ Precipitation Process (CIPS); a synthetic sandstone with silica intergranular cement; and a core sample from the Otway Basin Waarre Formation, Boggy Creek 1 well, from the target lithology for a trial $CO_2$ pilot project. Initial testing was carried on the cores at "room-dried" conditions, with confining pressures up to 65 MPa in steps of 5 MPa. All cores were then flooded with $CO_2$, initially in the gas phase at 6 MPa, $22^{\circ}C$, then with liquid-phase $CO_2$ at a temperature of $22^{\circ}C$ and pressures from 7 MPa to 17 MPa in steps of 5 MPa. Confining pressures varied from 10 MPa to 65 MPa. Ultrasonic waveforms for both P- and S-waves were recorded at each effective pressure increment. Velocity versus effective pressure responses were calculated from the experimental data for both P- and S-waves. Attenuations $(1/Q_p)$ were calculated from the waveform data using spectral ratio methods. Theoretical calculations of velocity as a function of effective pressure for each sandstone were made using the $CO_2$ pressure-density and $CO_2$ bulk modulus-pressure phase diagrams and Gassmann effective medium theory. Flooding the cores with gaseous phase $CO_2$ produced negligible change in velocity-effective stress relationships compared to the dry state (air saturated). Flooding with liquid-phase $CO_2$ at various pore pressures lowered velocities by approximately 8% on average compared to the air-saturated state. Attenuations increased with liquid-phase $CO_2$ flooding compared to the air-saturated case. Experimental data agreed with the Gassmann calculations at high effective pressures. The "critical" effective pressure, at which agreement with theory occurred, varied with sandstone type. Discrepancies are thought to be due to differing micro-crack populations in the microstructure of each sandstone type. The agreement with theory at high effective pressures is significant and gives some confidence in predicting seismic behaviour under field conditions when $CO_2$ is injected.

Plasma D-dimer Determination in the Diagnosis of Pulmonary Embolism (폐색전증의 진단에 있어 혈청 D-dimer 측정의 진단적 가치)

  • Lim, Chae-Man;Kim, Hong-Kyu;Choi, Kang-Hyun;Lee, Sand-Do;Koh, Youn-Suck;Kim, Woo-Sung;Jang, Jae-Suck;Kim, Dong-Soon;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.1
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    • pp.69-74
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    • 1996
  • Background: The diagnosis of pulmonary embolism (PE) based on clinical findings is often elusive and therefore requires confirmative diagnostic method. Pulmonary angiography, though the gold standard for the diagnosis of pulmonary embolism, is an invasive method and requires trained personnel and special equipment. Lung V/Q scan, on the other hand, is a noninvasive method but the diagnostic specificity and sensitivity arc not satisfactory in case that the results are either intermediate or low probability scan. Plasma D-dimer is generated when a thrombus is fibrinolysed by plasmin and is known to be increased in various thrombotic disorders. The aim of this study was to investigate the value of the determination of plasma D-dimer level in the diagnosis of pulmonary embolism. Methods: Pulmonary angiography was performed in 17 patients who were clinically suspected to have pulmonary embolism. 9 patients(PE, $56{\pm}13.4$ yrs, M:F=8:1) were diagnosed to have pulmonary embolism by pulmonary angiography. The control group were the 8 patients with negative pulmonary angiography and 13 orthopedic patients with no evidence of pulmonary embolism on scintigraphic and impedance plethysmographic studies(n=21) (non-PE, $54.5{\pm}11.1$ yrs, M:F=11:10). Plasma D-dimer was measured by latex agglutination method in study subjects and the results were analyzed according to the presence or absence of pulmonary embolism. Results: 1) The increased level of plasma D-dimer was more frequently observed in the patients with pulmonary embolism than in the controls(>0.5 mg/L, 8 in PE, 10 in non-PE; <0.5 mg/L, 1 in PE, 11 in non-PE, p=0.049). 2) The diagnostic value of plasma D-dimer level higher than 0.5 mg/L were as follows: sensitivity 88.9%(8/9), specificity 52.4%(11/21), positive predictive value 44.4%(8/18), and negative predictive value 91.7%(11/12). Conclusion: Plasma D-dimer determination showed high sensitivity and negative predictive value in the diagnosis of pulmonary embolism and is therefore thought to be useful in excluding the possibility of pulmonary embolism.

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A Structural Equation Modeling on Quality of Social Roles and Health for Married Working Mothers (유배우 취업모의 사회적 역할의 질과 건강에 대한 구조모형)

  • Park, Eun-Ok
    • Research in Community and Public Health Nursing
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    • v.12 no.2
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    • pp.450-458
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    • 2001
  • Purpose: The purpose of this study was to establish a structural equation model on social roles and health for married working mothers. to determine the effects of social roles on Korean women's health and to explore the mediating role of self-esteem in the relationship between social roles qualities and health. Method Data were collected from 323 employed women with partner and children. lived in Seoul and near Seoul. Response rate was 62.3%. The instruments for measurements were Role Quality Scale developed by Park et al. (1999). Rosenberg's Self-Esteem Scale. and 31 items from SF-36 developed by Ware & Sherboune(l992). Results: The effect of marital role quality on self-esteem and the effect of parental role quality on health were not significant. Modification model fitted with the collected data very well. as evidenced by the small chi-square(0.58), the very high goodness-of-fit(GFI = 1.00), and adjusted goodness-of-fit (AGFI = 0.99), and very small root mean square residual(RMSR=0.0072), and the slope of Q-plot is over 1. 41% of the variance in self-esteem and 21% of the variance in health were accounted for by these variables. Conclusion: Further research concerned with the mediating effects of self-esteem in the role and health relationship should be covered the issue of various role combinations. And it is necessary to examine the influence of subfactor of quality of social roles on health.

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Personality Type Test(MBTI) of the Korean Bruxism Patients (한국 이갈이 환자의 성격 유형 검사(MBTI))

  • Lee, Hyun-Ae;Auh, Q-Schick;Jung, Kee-Taig;Chun, Yang-Hyun;Hong, Jung-Pyo
    • Journal of Oral Medicine and Pain
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    • v.33 no.1
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    • pp.41-48
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    • 2008
  • The focus of this study is to analyze the effect of stress on the health of bruxism patients using the MBTI system. The most common personality type will be identified among the bruxism patients and by understanding their personality & their handling of stress, more comprehesive and effective treatment plan can be constructed. The study will also conclude that the type of personality has big effect on the cause of bruxism, and that this will be considered in the treatment plan in this hospital. The result of the study is as follow. First, more bruxism patients were type I than type E. It can be suggested that this result is due to the introversive people maintaining their energy how within themselves, and private are less to likely to release there stress than the expressive people. Second, among the bruxism patients significantly more type T were found compared to type F. This implies the bruxism tend to follow principals, scientific and analysing during decision making rather than basing their decision an meanings, emotions and influences. Thirdly, more bruxism patients clarified into ST in comparison to non-bruxism patients. This is thought to be due to probable increased stress and anxiety following ST people's tendency to more strict and realistic thinking according to effectiveness, evidence-based and productivity. Fourth, the type IJ was the most of the bruxism patients. We can come to the conclusion that decision-oriented introversion people who have hard to change, a thoroughgoing preparation characters are likely to grind their teeth by their detailed characters. Fifth, the type IT was the most of the bruxism patients. Bruxism patients are usually influenced by spirit, easily hearted, awed of relationship and attention. So, their intensity of stress is much bigger because of their personality. The last, Type IS was the most of the bruxism patients. It means that introvert sensitive types who have characters of calm, passive but defence to other's emotion, also neutral, keep moderation, and have cold-heartedness are likely to grind their teeth frequently. In conclusion it is evident that bruxism patients have particular personality types. Precisive, analysing and introversive bruxism patients are expected to have higher sensitivities to stress.

Biochemical Characterizations of Phenylalanine Ammonia-Lyase and its Mutants to Develop an Enzymatic Therapy for Phenylketonuria (페닐케톤뇨증의 효소치료 개발을 위한 phenylalanine ammonia-lyase 및 유전자 변이형의 생화학적 특성)

  • Kim, Woo-Mi
    • Journal of Life Science
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    • v.19 no.9
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    • pp.1226-1231
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    • 2009
  • Enzyme substitution with recombinant phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) is currently being explored for treatment of phenylketonuria (PKU), an autosomal recessive genetic disorder with mutations of the gene encoding phenylalanine-4-hydroxylase (EC 1.14.16.1). However, oral administration of PAL is limited because of proteolytic digestion in the gastrointestinal tract. The aim of this study was to determine the biochemical properties of PAL and delinate the susceptibility of wild-type PAL to pancreatic proteolysis by exploring several mutants, and to develop therapeutic drugs with PAL for PKU. The specific activity of PAL was assayed and its optimal pH, temperature stability, and intestinal protease susceptibility were investigated. Its $V_{max}$ values for phenylalanine and tyrosine were 1.77 and $0.47{\mu}mol$/ min/mg protein, respectively, and its $K_m$ values were $4.77{\times}10^{-4}$ and $4.37{\times}10^{-4}\;M$, respectively. PAL showed an optimal pH at 8.5, corresponding to the average pH range of the small intestine. It showed no loss of activity at $-80^{\circ}C$ for 5 months and possessed 93.4% of its activity under $4^{\circ}C$ for 4 wks. PAL was susceptible to chymotrypsin digestion and, to a lesser extent, to trypsin, elastase, carboxypeptidase A, and B. The trypsin and chymotrypsin cleaving sites were mutated to investigate protection from pancreatic digestion and the specific activities of these mutants were evaluated. The six mutants displayed low specific activities compared to the wild-type, suggesting that the primary trypsin and chymotrypsin cleaving sites may be essential for catalytic reaction. The PAL mutants could therefore be applied as a pretreatment modality without susceptibility to proteolytic attack, however, additional modification for enhancing enzymatic activity is needed to reduce the Phe levels effectively.

The Limnological Survey and Phosphorus Loading of Lake Hoengsung (횡성호의 육수학적 조사와 인부하)

  • Kwon, Sang-Yong;Kim, Bom-Chul;Heo, Woo-Myung
    • Korean Journal of Ecology and Environment
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    • v.37 no.4 s.109
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    • pp.411-422
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    • 2004
  • A limnological survey was conducted in a reservoir, Lake Hoengsung located in Kangwondo, Korea, from July 2000 to September 2001 on the monthly basis. Phosphorus loading from the watershed was estimated by measuring total phosphorus concentration in the main tributary. Secchi disc transparency, epilimnetic (0-5 m) turbidity, chlorophyll a (Chl-a), total phosphorus (TP), total nitrogen(TN) and silica concentration were in the range of 0.9-3.5 m, 0.1-8.5 NTU, 0.3-32.4 mgChl $m^{-3}$, 5-46 mgP $m^{-3}$, 0.83-3.55 mgN $L^{-1}$ and 0.5-9.6 mgSi $L^{-1}$, respectively. Green algae and cyanobacteria dominated phytoplankton community in warm seasons, from July through October, 2000. In July a green alga (Scenedesmus sp.) was dominant with a maximum cell density of 10,480 cells mL. Cyanobacteria (Microcystics sp.) dominated in August and September with cell density of 3,492 and 295 cells mL ,respectively. Species diversity of phytoplankton was highest (2.22) in July. The trophic state of the reservoir can be classified as eutrophic on the basis of TP, Chl-a, and Secchi disc transparency. Because TP concentration was high in flood period, most of phosphorus loading was concentrated in rainy season. TP loading was calculated by multiplying TP and flow rate. The dam managing company measured inflow rate of the reservoir daily, while TP was measured by weekly surveys. TP of unmeasured days was estimated from the empirical relationship of TP and the flow rate of the main tributary; $TP=5.59Q^{0.45}\;(R^2=0.47)$. Annual TP loading was calculated to be 4.45 tP $yr^{-1}$, and the areal P loading was 0.77 gP $m^{-2}\;yr^{-1}$ which is similar to the critical P loading for eutrophication by Vollenweider's phosphorus model, 0.72 gP $m^{-2}\;yr^{-1}$.