• Title/Summary/Keyword: response-surface

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Effects of potassium channel modulators on the fatigue velocity of mouse skeletal muscle (K+ 통로 조절 약물이 마우스 골격근의 피로현상에 미치는 영향)

  • Lee, Ki-ho;Ryu, Pan-dong;Lee, Mun-han;Lee, Hang
    • Korean Journal of Veterinary Research
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    • v.35 no.2
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    • pp.245-254
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    • 1995
  • The density of ATP-sensitive potassium($K_{APT}$) channels, that open as intracellular ATP concentration falls below a critical level, is very high in skeletal muscle surface membrane and those high density may imply that $K_{ATP}$ channels have very important physiological roles. To elucidate a role of $K_{ATP}$ in relation to fatigue, the modulating effects of potassium channel openers and blockers on the fatigue velocity(FV) of mouse extensor hallucis longus muscle(EHL) were investigated in vitro. Twitch contraction was induced by an electrical field stimulation (EFS: 24-48V, 20ms, 0.2-4Hz) and resulting contraction force was isometrically recorded. The twitch forces were gradually decreased to 25% of initial contraction force(ICF) in $37.52{\pm}1.55sec$($mean{\pm}s.e.m.$, n=135), indicating the fatigue phenomena. The mean velocity for development of the fatigue was measured during the period that twitch force decreased to half($FV_{0/0.5}$) and during the period from half to 25%($FV_{0.5/0.25}$) of ICF. The fatigue was induced once every one hour and the tissue response was stable for up to 4 hours. In control condition, ICF was $5.8{\pm}0.12g$ (n=144) and decreased to 50% of ICF with the mean fatigue velocity of $0.182{\pm}0.006g/sec$($FV_{0/0.5}$, n=135) and from 50% to 25% of ICF with $0.084{\pm}0.004g/sec$($FV_{0.5/0.25}$, n=135). Cromakalim($50{\mu}M$) significantly increased $FV_{0.5/0.25}$(n=4). Glibenclamide($IC_{50}>50{\mu}M$), $Ba^{2+}$($IC_{50}=10{\mu}M$), 4-aminopyridine($FV_{0/0.5}$, $IC_{50}=0.5mM$; $FV_{0.5/0.25}$, $IC_{50}=2mM$) decreased both $FV_{0/0.5}$ and $FV_{0.5/0.25}$ concentration-dependently up to 75%. $TEA^+$(30mM), E-4031($10{\mu}M$), tolbutamide(1mM) decreased $FV_{0.5/0.25}$, but apamin(300nM) and $TEA^+$(10mM) showed no significant effects. Our results suggest that activation of the $K_{ATP}$ channels may be major cause of $K^+$ outflux during development of the fatigue and the isolated EHL muscle could be an useful experimental preparation in studying the fatigue phenomena in skeletal muscle. In addition, the possibility of activation of delayed rectifier during the fatigue development remains to be studied further.

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Effect of Extract or Crude Enzyme Extracted from the Fruit of Paper Mulberry (Broussonetia kazinoki Siebold) on Tenderness and Palatability of Jangchorim (닥나무 열매(緖寶子)의 농축액과 조효소가 장조림의 맛과 연화에 미치는 영향)

  • 윤숙자;장명숙
    • Korean journal of food and cookery science
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    • v.13 no.5
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    • pp.617-622
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    • 1997
  • The purpose of this study was to investigate the effect of the addition of the extract (0, 2, 4, 6, 8%) and crude enzyme (0, 0.05, 0.1, 0.5, 1%) extracted from the fruits of paper mulberry (Broussonetia kazinoki Siebold) on the tenderness and palatability of Jangchorim. Addition of up to 8% of the extract diminished the shear force by 4.8∼27%, while the addition of up to 1% of the crude enzyme begot 7.8∼34.2% decrease. Also, as the addition of the fruits of paper mulberry increased, the cooking loss was somewhat decreased, an the redness of cooked beef surface and free amino acid content in the liquid part of Jangchorim were generally increased. The contents of the mineral were in the order of Na, K, P, Ca, and Mg when crude enzyme was added. In sensory evaluation, the 4% crude extract from the fruit of paper mulberry and 0.1% addition in its crude enzyme showed the most favorable response.

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Optimization of Goat Milk Yoghurt Preparation Conditions by Response Surface Methodology (반응표면 분석에 의한 산양유 요구르트의 제조조건 최적화)

  • Ham, Jun-Sang;Jeong, Seok-Geun;Shin, Ji-Hye;Choi, Mi-Young;Han, Gi-Sung;Chae, Hyun-Seok;Yoo, Young-Mo;Ahn, Jong-Nam;Ko, Sang-Hyun;Park, Kwang-Wook;Choi, Seok-Ho;Lee, Wan-Kyu
    • Food Science of Animal Resources
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    • v.27 no.3
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    • pp.345-350
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    • 2007
  • This study was carried out to establish the optimal preparation conditions of yoghurt made from goat milk with reduced goaty flavor by adding citrus concentrate and flavor. A central composite design was applied to investigate the effects of citrus concentrate ratio (0.5, 1.0, 1.5, 2.0, 2.5%), citrus flavor ratio (0.01, 0.02, 0.03, 0.04, 0.05%) and fructose ratio (3, 4, 5, 6, 7%). The physico-chemical and sensory characteristics of the sixteen yoghurt samples were compared. The addition of citrus concentrate had a significant (p<0.01) effect on the pH, $a^*,\;and\;b^*$ values. Regarding organoleptic properties, the addition of citrus concentrate had a significant (p<0.01) effect on color, and fructose had an effect on overall palatability. The maximum value of organoleptic goaty flavor was 2.35, more than double the minimum value. The optimum conditions predicted for minimizing goaty flavor of the yoghurt were 1.44% citrus concentrate, 0.0357% citrus flavor, and 6.91% fructose.

Multiple Cavitary Pulmonary Metastases from Cholangiocarcinoma (담관암의 다발성 공동성 폐전이)

  • Do, Mi Young;Chung, Jae Ho;Kim, Hee Man;Han, Seung Jin;Shim, Jae Min;Hwang, Sang Yon;Park, Moo Suk;Kim, Young Sam;Chang, Joon;Kim, Sung Kyu;Park, Seung Woo;Choe, Kyu Ok;Shin, Dong Hwan;Kim, Se Kyu
    • Tuberculosis and Respiratory Diseases
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    • v.56 no.2
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    • pp.216-220
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    • 2004
  • Because a cavitary pulmonary metastasis is rare, it may not be readily identified. However, various types of cancers can metastasize to the lung in the form of cavities. We report a case of a multiple cavitary metastases to the lung from a cholangiocarcinoma in a 60-year-old man. He complained of generalized weakness and a poor oral intake for 2 months. The plain chest radiography and the chest computed tomography showed multiple small thick-walled cavities and nodules the both lungs. A bronchoscopic examination revealed a focal irregularly elevated surface of the mucosa at the orifice of the superior segment of the right lower lobe and the biopsy demonstrated an infiltrative metastatic adenocarcinoma. The abdomen-pelvis computed tomography showed an ill-marginated and irregularly low-dense area in the right lobe of the liver and a diffuse dilatation of the peripheral intrahepatic bile ducts. The esophagogastroscopy and colonoscopy showed no abnormal findings. It was concluded that the cholangiocarcinoma of the liver metastasized to the lung in the form of cavities. Thereafter, the patient underwent six cycles of the systemic chemotherapy with gemcitabine and cisplatin, and the follow-up imaging studies showed a partial response.

Diagnostic Utility of Pleural Fluid Soluble Triggering Receptor Expressed on Myeloid Cells 1 Protein in Patients with Exudative Pleural Effusion (삼출성흉수에서 Soluble Triggering Receptor Expressed on Myeloid Cells 1 Proteion의 진단적 유용성)

  • Sim, Yun Su;Lee, Jin Hwa;Cheun, En Mi;Chang, Jung Hyun
    • Tuberculosis and Respiratory Diseases
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    • v.62 no.6
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    • pp.499-505
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    • 2007
  • Background: Triggering receptor expressed on myeloid cells 1 protein (TREM-1) is a cell surface molecule expressed on neutrophils and monocytes, and it plays an important role in myeloid cell-activated inflammatory response. The aim of this study was to investigate the diagnostic efficiency of soluble (s) TREM-1 in the patients who had pleural effusion from various causes. Methods: Forty-five patients with exudative pleural effusion were included in this study. The level of sTREM-1 was measured in both the serum and pleural fluids by immunoblot assay with using human-sTREM-1 antibody. Results: The pleural fluid sTREM-1 was significantly different in the three groups of exudative pleural effusion (p=0.011). Particularly, the patients with parapneumonic effusion were found to have significantly higher pleural fluid levels of sTREM-1 than patients with tuberculous (p<0.05) and malignant effusion, respectively (p<0.05). However, the serum sTREM-1 did not show a significant difference in the three groups. In order to evaluate the diagnostic utility of pleural fluid sTREM-1, the receiver operating characteristic (ROC) curve was constructed and the area under the curve (AUC) was 0.818 (p=0.001). Using a cutoff value of 103.5 pg/mL for the pleural fluid sTREM-1, the sensitivity and specificity were 73% and 81%, respectively, for differentiating parapneumonic effusion from tuberculous or malignant effusions. Conclusion: Pleural fluid sTREM-1 can be an additional marker for making the differential diagnosis of pleural effusion.

Evaluation of Clinical Usefulness of EIS(Electro Interstitial Scan) (EIS(Electro Interstitial Scan) 방법의 임상적 유효성 연구)

  • Kim, Soochan;Bae, Jang-Han;Jun, Min-Ho;Kim, Jaeuk U.
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.12
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    • pp.124-133
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    • 2015
  • Electro interstitial scan shows potential as a non-invasive screening method. It can discriminate some diseases based on electric current response to induce low intensity direct current to limbs or local area of body. DDFAO was invented in France and it is claimed that multi-channel EIS(Electro Interstitial Scan) is useful for various diseases, especially, diagnoses of endocrine system such as diabetics are very effective. In this study, we verified the repeatability and sensitivity of DDFAO by using a RC phantom model and its clinical usefulness using data obtained from normal and diabetes subject groups. As a result, it showed the repeatability and the output change according to change of phantom characteristic, but it was hard to distinguish normal and patient groups non-invasively with just six surface electrodes of DDFAO. The repeatability and the clinical accuracy was not sufficient for screening or diagnostic purposes, as well. In spite of the results with low repeatability and accuracy conducted in this study, we still need further investigations to improve the EIS-based measurement method; EIS is very convenient and simple and it shows potential as a screening tool of the whole body health conditions rather than localized disease diagnosis.

The study on the quality standards of groundwater in Korea in comparing to the developed countries (우리나라와 선진국간의 지하수 수질기준에 관한 고찰)

  • Bang, Sang-Weon;Jung, Jae-Hyun
    • Journal of Environmental Policy
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    • v.4 no.2
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    • pp.57-82
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    • 2005
  • In this study, we propose methods for. the efficient management and integrity of groundwater in response to a diminishing supply. As an alternative water resource for the future. we investigated and comparatively analyzed the quality standards of groundwater in the US (New York, Wisconsin and Texas), Austria, Netherlands, Canada, Japan and United Kingdom. These developed countries heavily depend on groundwater, more than 70%, for drinking water and apply those drinking water standards to groundwater quality. However, there exists few differences in the quality standards of groundwater among the countries, because each country possesses its own individual environment and management. In Korea, surface water pollution is getting serious and its water resources are diminishing. Therefore we propose several new quality criteria that many countries regulate at these days for their efficient management of groundwater. There is a need to divide BTEX criterion into Benzene, Toluene, Ethylbenzene and Xylene, individually. In. addition, it is needed to establish BTEX criteria into agricultural water and industrial water use standards as well as daily life use standards. Also, regulations for some PAHs, showing carcinogenicity, are required. Due to rapid industrialization various hazardous chemicals were utilized and their uses are increasing each year. Therefore, there is a strong need to introduce n~w standards and tighter regulations of the levels. At the same time, the criterion of nitrogenous compounds need' to be regulated individually in order to prevent the damage incurred by the compounds. Several developed countries have established standards for radon, previously caused environmental accidents in Korea. Therefore, we propose the necessity of groundwater quality standards for radon in this study.

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The Gifted Students' View on Argumentation and the Aspects of the Argumentation in Problem-Solving Type Experiment (문제해결형 탐구실험에서 나타난 영재학생들의 논의 양상 및 논의활동에 대한 인식)

  • Shin, Ho-Sim;Kim, Hyun-Joo
    • Journal of The Korean Association For Science Education
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    • v.31 no.4
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    • pp.567-586
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    • 2011
  • The purpose of this study was to investigate the gifted students' view on argumentation and the aspects of the argumentation in problem-solving type experiment. As a result, very lively argumentation was identified but quality enhancement on argumentation wasn't found over time. Students made frequent use of dialogic argumentation component, and especially, request & response component was highly used. Though usage frequency is low, the component of ground & question on ground was shown in 3rd class, and simple agreement gradually reduced, and reinforcing elaboration & metacognitive question has slightly increased. Also, students' argumentation were closely related to teachers' teaching approaches as some teacher-led steps doesn't appear in students' argumentation. By comparison in steps, 'problem solving activity & result analysis' step included 2 times more argument components than the previous step. We also found that method grouping teams does not almost affect the argumentation of gifted students. By survey results, most students recognized that they experienced free argumentation and this program activate argumentation and 'strange things' or 'difficulty' of program topics are obstacles in vitalization of argumentation. 'Surface growth experiments' was the most lively argumentation topic. The argumentation was lively made in the step of 'finding solution. 'Teachers' scaffolding accelerate the argumentation and help resolve difficulties in argumentation. Thus, students have positive recognition for the argumentation process in the experiments and recognize that argumentation process is needed.

Studies on the Fermentation Characteristics of Yogurt Added with Pregelatinized Rice Flour (호화쌀가루를 첨가한 요구르트의 발효특성에 관한 연구)

  • Kim, Soo-Hee;Kim, An-Na;An, Byung-Kyu;Choi, Soo-Keun
    • Culinary science and hospitality research
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    • v.20 no.4
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    • pp.37-48
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    • 2014
  • The purpose of this study is developing a formulation with an optimum sensory point by using yogurt added with rice flour and pregelatinized rice flour(alpha rice flour) optimized by response surface method(RSM). The pH, acidity, sugar content, viscosity and number of lactic acid bacteria during fermentation of two types of yogurt(added with rice flour and pregelatinized rice flour) optimized by RSM were analyzed As the fermentation time of both types of yogurt increased, pH showed decreasing trend. The titratable acidity showed increasing trend as fermentation time increased. Sugar content decreased as fermentation time increased. The reasons are believed to be the sugar decrease during glycolysis and lactic acid fermentation. Viscosity was the highest at 6 hours of fermentation. After 10 hours of fermentation, the viscosity was higher than it was before the fermentation. The number of lactic acid bacteria of yogurt added with rice flour and pregelatinized rice flour was 7.43~9.00 log CFU/mL, which is more than optimum value. Therefore, it is possible to confirm that adding rice flour during yogurt manufacturing increases the number of lactic acid bacteria.

Monitoring of Roast Color Formation in Ginseng Using Threonine and Sucrose (Threonine과 Sucrose를 이용한 인삼의 색상 발현 모니터링)

  • Lee, Gee-Dong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.5
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    • pp.735-740
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    • 2014
  • The study investigated the roast color formation properties of ginseng upon soaking in threonine/sucrose solution followed by roasting. To determine operational parameters, including threonine concentration ($X_1$, 0.1~0.9%), sucrose concentration ($X_2$, 1.0~3.0%), and roasting temperature ($X_3$, $130{\sim}170^{\circ}C$), response surface methodology was applied to monitor color properties, including brown color intensity, Hunter's colors, and organoleptic color. Coefficients of determinations ($R^2$) of the models were above 0.8758 (P<0.05) in terms of brown color intensity and Hunter's color parameters. Brown color intensity of roasted ginseng extract was maximized in 0.70% threonine and 2.32% sucrose soaking solution under roasting conditions of 25 min at $166.03^{\circ}C$. a values of roasted ginseng were maximized in 0.74% threonine and 2.19% sucrose soaking solution under roasting conditions of $165.40^{\circ}C$. b values of roasted ginseng were maximized in 0.61% threonine and 2.28% sucrose soaking solution under roasting conditions of $159.16^{\circ}C$. The maximum organoleptic color score of roasted ginseng extract was 7.27 in 0.53% threonine and 1.01% sucrose soaking solution under roasting conditions of $146.96^{\circ}C$.