• Title/Summary/Keyword: response-surface

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Measurement of Dose outside a 6 MV Field Edge Using Optically Stimulated Luminescent Nano Dot Dosimeters (광자극형광나노닷선량계를 사용한 6 MV 조사야 가장자리 바깥 선량 측정)

  • Kim, Jongeon;Kim, Wontae
    • Journal of the Korean Society of Radiology
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    • v.8 no.7
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    • pp.449-454
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    • 2014
  • The purpose of this study is(was) to investigate the shielding ratio of 1 mmPb and the off axis ratio outside the field edge at depth of 1 cm from a phantom surface for 6 MV photon beam. A dose of 180 cGy was delivered to a depth of 10 cm for a $10{\times}10cm^2$ and $15{\times}15cm^2$ field in the SAD technique. The off axis ratio was calculated by measuring the dose of optically stimulated luminescent nanoDot dosimeters(OSLnDs) positioned at 2, 4 and 6 cm from the field edge, and the center axis of field. And the shielding ratio of 1 mmPb was calculated by measuring the dose of OSLnDs positioned at 2, 4 and 6 cm from the field edge.. As a result, for a $10{\times}10cm^2$ and $15{\times}15cm^2$ field, the off axis ratios were acquired 0.008-0.023 and 0.011-0.028, respectively. Also the shielding ratios of 1 mmPb were acquired 0.868-0.888 and 0.807-0.842, respectively. These results provide data to protect organs at risk outside the radiation treatment field.

Biological Degradation of Cypermethrin by Marine Bacteria, Cellulophaga lytica DAU203 (해양 세균 Cellulophaga lytica DAU203에 의한 사이퍼메트린의 생물학적 분해)

  • Lee, Je-Hoon;Lee, Yong-Suk;You, Ah-Young;Choi, Yong-Lark
    • Journal of Life Science
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    • v.28 no.4
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    • pp.483-487
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    • 2018
  • Cypermethrin, a commonly used domestic and agricultural pyrethroid pesticide, is widely considered detrimental to the environment and to many organisms because of its residual property and toxicity. Cellulophaga lytica DAU203, isolated from coastal sediment, was chosen because it degrade cypermethrin. Cellulophaga lytica DAU203 effectively degraded cypermethrin, as the utilized carbon source and substrate, in a mineral salt medium. Effective factors, such as carbon source, nitrogen source, initial pH, and temperature, for cypermethtin biological degradation by Cellulophaga lytica DAU203 were analyzed by one factor at a time method. Temperature ($22{\sim}42^{\circ}C$), initial pH (5~9), and yeast extract concentration (0.1~2.5%[w/v]) were selected as the three most important factors. There were optimized at $33.4^{\circ}C$, pH 7.7, and 2.4%(w/v) by response surface methodology, respectively. The Box- Behnken design consisting of 46 experimental runs with three replicates was used to optimize the independent variables which significantly influenced the cypermethrin biological degradation. This model for cypermethrin degradation by Cellulophaga lytica DAU203 is highly significant (p<0.05). Under the optimized condition, Cellulophaga lytica DAU203 degraded approximately 83.7 % of the cypermethrin within 5 days. These results suggest that Cellulophaga lytica DAU203 may be useful for the biological degradation of cypermethrin in cypermethrin-contaminated environments.

Morphological Variation and Density of Euglena viridis (Euglenophyceae) Related to Environmental Factors in the Urban Drainages (도시하천의 환경요인과 Euglena viridis의 형태 변이 및 밀도와의 관계)

  • Kim, Jun-Tae;Boo, Sung-Min
    • Korean Journal of Ecology and Environment
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    • v.34 no.3 s.95
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    • pp.185-191
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    • 2001
  • The morphological variation and density of the Euglena viridis cells and environmental factors of urban waterways of Daejoncheon , Jeonjucheon, Kwangjucheon, Kumhogang, Mihocheon,and Musimcheon, Korea were studied from 25December, 1995 to 5 January, 1997 in order toelucidate possible relationships among the bio-logical and abiological factors. All E. viridis cells were same in having single star-cluster of chlo-roplast lobes and included two morphotypes based on other detailed morphology. The morphotype I cells agreed well with the typical form off. viridrs and commonly occurred in most of waters and bloomed with $5386\;cells\;{\cdot}\;mL^{-1}$ in Kwangjucheon. The density of the morphotype Ipositively correlated with ammonium (r = 0.80)and nitrite (r = 0.68), while negatively with nit-rate concentration. The morphotype II cells were characterized by having randomly scattered cytoplasmic granules beneath pellicle and unevenmargined lobes of chloroplasts. The density of the morphotype II positively correlated with nitrate (r = 0.98), while negatively correlated with ammonium and nitrite. However, the density of each morphotype was not significantly related with inorganic phosphate, temperature and pH of surface water. These results indicate that E. viridis includes two morphotypes in urban waterways in Korea, that coexist in the same period and station as a response of allocation of nitrogenous nutrients.

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Effects of Different Exercise Intensities on GLUT-4 and GRP-78 Protein Expression in Soleus Muscle of Streptozotocin-Induced Diabetic Rats with Caffeine Oral Administration (카페인 경구투여가 운동강도 차이에 따른 당뇨유발 흰쥐 가자미근의 GLUT4 및 GRP78 단백질 발현에 미치는 영향)

  • Yoon, Jae-Suk;Yoon, Jin-Hwan
    • Journal of Life Science
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    • v.14 no.5
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    • pp.741-746
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    • 2004
  • This study investigated the response of GLUT-4 and GRP-78 protein expression in soleus muscle of Streptozotocin-induced diabetic rats with caffeine oral administration by imposing different exercise intensities. Rats were randomly divided into 5 groups (n=6 in each group): diabetic group (D), diabetic-caffeine group (DC), diabetic-caffeine group with low intensity exercise (DCL), diabetic-caffeine group with moderate intensity exercise (DCM) and diabetic-caffeine group with high intensity exercise (DCH). The rats in DCL, DCM and DCH groups were exercised acutely by treadmill running for 8 meter/m, 16 meter/m and 25 meter/m, respectively. Little difference in GLUT-4 protein expression was shown in DC and DCL compared to D. GLUT-4 protein expression was decreased in DCM and increased in DCH was observed. GRP-78 protein expressions in DCL, DCM and DCH were little lower than that of D. An increase in GRP-78 protein was observed in DC. Improved insulin sensitivity with acute high intensity exercise gives the rats important therapy that lowers insulin requirement. This improvement of insulin sensitivity for glucose transport in skeletal muscle results from translocation of the GLUT-4 protein from the endoplasmic reticilum to the cell surface and increase in total quantity of GLUT-4 protein. It is not clear what mechanism reduced GRP-78 protein level in exercise group. It is merely conjectured that caffeine-induced lipolysis provided cells with energy in abundance and this relieved stress which cells are subjected to receive when performing exercise.

Optimum Enzyme Mixture of Cellulase, Hemicellulase, and Xylanase for Production of Water-Soluble Carbohydrates from Rice Straw (볏짚 유래 수용성 탄수화물 생산에 있어 cellulase, hemicellulase 및 xylanase 최적혼합조건)

  • Cho, Sang-Buem;Lee, Sang-Suk;Kim, Chang-Hyun;Ryu, Kyeong-Seon;Park, Hee-Jun;Myong, Hyun;Choi, Nag-Jin
    • Journal of Life Science
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    • v.22 no.1
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    • pp.74-79
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    • 2012
  • This study was conducted to investigate the production of water-soluble carbohydrates (WSCs) by treatment of different amounts of rice straw with cellulase, hemicellulase, and xylanase. Treatment of high amounts of rice straw (100 g/l) with cellulase and hemicellulase resulted in similar production of WSCs. Reducing the amount of rice straw to 50 g/l decreased the production of WSCs by hemicellulase but had no effect on WSC production by cellulase. The interaction among rice straw amounts, and hemicellulase and xylanase activities was investigated using a Box Behnken design and a response surface model. An interaction was found only between hemicellulase and xylanase. An enzyme mixture consisting of 0.55 mg/ml of hemicellulase and 0.65 mg/ml of xylanase generated the highest amounts of WSCs, regardless of the amount of rice straw provided. Therefore, the activity of cellulase was higher than that of either hemicellulose or xylanase for WSC production from rice straw. The interaction observed for hemicellulase and xylanase indicates that a combined enzyme treatment could improve the production of WSCs from rice straw.

Monitoring for the Color Formation of a Doraji Tea by Soaking of Threonine and Sucrose Solution and Roasting (Threonine과 Sucrose 용액에 침지 및 볶음에 의한 도라지차의 색상 발현 모니터링)

  • Lee, Gee-Dong;Jeong, Yong-Jin;Park, Nan-Young;Kwon, Joong-Ho
    • Korean Journal of Food Science and Technology
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    • v.31 no.4
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    • pp.938-944
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    • 1999
  • Response surface methodology (RSM) was used for monitoring the changes of Hunter's color and organoleptic colors of roasted doraji tea with variations in threonine concentration of soaking solution and roasting condition. In soaking and roasting processes based on the central composite design with variations in threonine concentration of soaking solution, roasting temperature and roasting time, coefficients of determinations $(R^{2})$ of the models were above 0.87 (p<0.05) in Hunter's color parameters and organoleptic color. Hunter's color L value of roasted doragi tea was maximized in 0.09% threonine concentration of soaking solution, $142.37^{\circ}C$ and 21.94 min in roasting condition. Hunter's color a value of roasted doragi tea was maximized in 1.24% threonine concentration of soaking solution, $154.01^{\circ}C$ and 28.59 min in roasting condition, minimized in 1.67% threonine concentration of soaking solution, $137.61^{\circ}C$ and 24.62 min in roasting condition, Hunter's color b value of roasted doragi tea was maximized in 1.10% threonine concentration of soaking solution, $154.72^{\circ}C$ and 27.12 min in roasting condition. The maximum quality of organoleptic color of roasted doragi tea was soaked in 1.25% threonine concentration, and roasted at $141.81^{\circ}C$ for 34.14 min.

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Growth response of Calla (Zantedeschia) to root zone environmental conditions in Highland (고랭지에서의 근권환경에 따른 유색칼라(Zantedeschia)의 생육반응)

  • Nam, Chun-Woo;Yoo, Dong-Lim;Kim, Su-Jeong;Suh, Jong-Teak;Paek, Kee-Yoeup;Lee, Sang Gyu;Yoon, Moo Kyung
    • Korean Journal of Agricultural Science
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    • v.40 no.4
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    • pp.325-331
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    • 2013
  • This experiment has been carried out to determine optimal culture conditions for the production of cut flowers and tubers of Calla (Zantedeschia 'Golden Affair' and 'Black Magic') in highlands. Treatments consisted of various levels of root zone environments, Results are as follows: Calla 'Golden Affair' were grown with different mulching materials such as Non-mulching, Black film, reflective film, Rice hull. Mulching materials resulted in no difference in the number of cut flowers but flower length was highest in reflective film. Calla 'Black Magic' were treated with various soil water content, soil type and watering time. Number of cut flowers and flower quality were greatest when the plants were watered at -80 kPa soil water content. No symptoms of soft rot (Erwinia carotovora) was observed at this soil water content. The occurrence of soft rot was observed with similar percentage according to soil type and the soil water content. When Calla 'Black Magic' were watered at the time of soil surface drying, growth was greater compared to others. Air temperature and PPF affected plant growth and photosynthesis. Photosynthetic rate was greatest at $25^{\circ}C$ and PPF $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, while lowest at $28^{\circ}C$ and PPF $800{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Soft rot did not occur without regard to dipping treatment (0, 5, 10, 24, 48 hours) when the day and night temperature were maintained at $25^{\circ}C$ and $20^{\circ}C$, respectively.

Protective Effect of Rhus Semialata M. extract on Epidermal Stem Cells against UV Irradiation (자외선 조사된 상피 줄기세포에 대한 붉나무 추출물의 보호 효과)

  • Woo, Hyunjoo;You, Jiyoung;Park, Deokhoon;Jung, Eunsun
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.45 no.4
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    • pp.415-422
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    • 2019
  • Human epidermal stem cells(ESCs) residing in the basement membrane of the skin have an important role in maintenance of skin homeostasis of epidermal layer. Although, ESCs provide new cells to repair damaged tissue in response to tissue injury, subsets of stem cells remain in the quiescent state protected from differentiation and senescence for prolonged survivals. In this perspective, the stem cell niche, which is specific microenvironment composed of niche cells and an extracellular matrix(ECM), supplies the relevant signal to save stem cells from microenvironmental damages. The expression of stemness marker on the surface of ESCs contributes to the attachment on their ECM of the basement membrane, which lead to growth potential and apoptotic resistance against environmental stimuli. In this study, we observed that UV irradiation, a major factor of environmental stimuli, reduced the expression of α2, β1 and α6 integrin in ESCs. Rhus Semialata M extract(RSE) showed inhibitory effect on the UVB-induced reduction of integrin expression. Furthermore, RSE could upregulate the expression of Col-IV and Laminin, which contribute to the attachment of ESCs. These results indicated that RSE could be a potent ingredient for the protection of ESCs from UV irradiation by increasing the expression of integrin and substrate ECM components at their niche.

Antioxidative and Nitrite Scavenging Activities of Polygonatum odoratum Root Extracts with Different Steaming and Roasting Conditions (둥굴레 근경의 증자 및 볶음조건에 따른 추출물의 항산화성 및 아질산염 소거능 변화)

  • Kim Kyung-Tae;Kim Jung-Ok;Lee Gee-Dong;Kwon Joong-Ho
    • Food Science and Preservation
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    • v.12 no.2
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    • pp.166-172
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    • 2005
  • Response surface methodology (RSM) was applied to monitor the effects of steaming and roasting conditions of Polygonatum odoratum roots an total phenolics content, electron donating ability (EDA) and nitrite-scavenging ability (NSA) of the extract. In steaming and roasting processes based on the central composite design. with variations in steaming time $(60\~180\;min)$, roasting temperature $(110\~150\;min)$ and roasting time $(10\~50\;min)$, coefficients of determinations $(R^2)$ were 0.9356 (p<0.01) in total phenolics, 0.9578 (p<0.01) in EDA and 0.9436 (p<0.01) in NSA (pH 3.0). The maximum value of total phenolics was $2847.67\;mg\%$ at 135.59 min of steaming time, $143.84^{\circ}C$ of roasting temperature and 43.47 min of roasting time. The maximum value of EDA was $75.00\%$ in 108.98 min, $135.56^{\circ}C$ and 48.86 min. The maximum value of NSA (pH 3.0) was $87.38\%$ in 162.80 min, $143.88^{\circ}C$ and 31.97 min, respectively. Total phenolics content of the extract was influenced by heating conditions in the order of roasting temperature, steaming time and roasting time. While EDA and NSA were appreciably influenced by roasting time, followed by roasting temperature and steaming time.

Gait Phases Detection from EMG and FSR Signals in Walkingamong Children (근전도와 저항 센서를 이용한 보행 단계 감지)

  • Jang, Eun-Hye;Chi, Su-Young;Lee, Jae-Yeon;Cho, Young-Jo;Chun, Byung-Tae
    • Science of Emotion and Sensibility
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    • v.13 no.1
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    • pp.207-214
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    • 2010
  • The aim of this study was to investigate upper and lower limb muscle activity using EMG(electromyogram) sensors while walking and identify normal gait pattern using FSR(force sensing resistor) sensor. Fifteen college students participated in this study and their EMG and FSR signal were measured during stopping and walking trials. EMG signals from upper(pectoralis major and trapezius) and lower limbs(rectus femoris, biceps femoris, vastus medialis, vastus lateralis, semimembranosus, semitendinosus, soleus, peroneus longus, gastrocnemius medialis, and gastrocnemius lateralis) were obtained using the surface electrodes. FSR measured pressures on 8 areas of the sole of the foot during walking. EMG results showed that all muscle activities except for vastus lateralis and semimembranosus during walking had higher amplitudes than stopping. Additionally, muscle activities associated with stance and swing phase during walking were identified. Results on FSR showed that stance and swing phases were detected by FSR signals during a gait cycle. Eight gait phases-initial contact, loading response, mid stance, terminal stance, pre swing, initial swing, mid swing, and terminal swing- were classified.

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