• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.5
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• pp.228-236
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• 2009

In this study, we investigated morphological characteristics of $SF_6$ clathrate hydrate crystals to understand its formation and growth mechanism. $SF_6$ clathrate hydrate crystals were formed in high-pressure reaction cell charged with pure water and $SF_6$ gas at constant pressure and temperature. Two-phase ($SF_6$ gas/aqueous solution) and three-phase ($SF_6$ gas/aqueous solution/$SF_6$ liquid) conditions were investigated, In both conditions, dendritic shape hydrate crystals were grown as like fibriform crystals along upward growth direction at the gas/aqueous solution interface. In the case of the reaction process of three-phase condition, when the $SF_6$ gas bubbles which were generated in $SF_6$ liquid phase due to the reduction of reaction cell pressure stuck to the gas/aqueous interfaces, the hydrate phase were appeared at the surface of the bubbles. This paper presents the detail growth characteristics of $SF_6$ hydrate crystals including crystal nucleation, migration, growth and interference.

• Journal of Korean Society of Forest Science
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• v.96 no.3
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• pp.235-244
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• 2007

Potentials of AR CDM project in North Korea are assessed and feasible land area for AR CDM project is estimated. According to our estimation, There could be 515,000 hectares of forest lands deforested before 1990 in North Korea and 8,854 hectares at the regional level of Gae-sung City, which are eligible for AR CDM project, based on researches of satellite image analyses conducted from 1980's to 1990's. A baseline scenario assumed 44.73 tones of carbon stored in soil per hectare with no vegetation above ground remained during the project period following the default value of IPCC's Good Practice Guidance for LULUCF considering soil structure, climate and land use of the project area. The scenario also assumes that black rocust (Robinia pseudoacacia) is planted and the CDM project is implemented for 20 years. The costs for producing greenhouse gases CER (certified emission reduction) credits include costs of tree planting and forest management, and costs of project negotiation and transactions for issuing the credits. It is estimated that 376 tones of carbon dioxide per hectare can be accumulated and 503 temporary CER credits per hectare and 265 long-term CER credits per hectare could be produced during the project period. It is estimated to cost US$ 4.04 and US$ 7.67 to provide one unit of temporary credit and long-term credit, respectively. These values can be regarded as the cost of conferring emission commitment of a country or a private entity. However, it is not clear which option is better economically because the replacement periods are different in these two cases.

• The Journal of Korean Medicine
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• v.28 no.2 s.70
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• pp.93-113
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• 2007

Objective : To research Trends of studies about anti-inflammation and pain relief, obesity, and safety of herbal acupuncture therapy by analyzing domestic theses, published since 2001, about herbal acupuncture therapy. Methods : Domestic theses, published since 2001, mentioning anti-inflammation or pain relief, obesity, or safety of herbal acupuncture therapy were reviewed and analyzed. These theses were then classified by university, year, and subject. Results : The following results were obtained in this study. 1. Among published theses related to anti-inflammation effects of herbal-acupuncture, studies about arthritis comprised the most part, 52. In theses relating to causes of arthritis, 16 were about adjuvant, which was the most, followed by Type II collagen, LPS and carrageenan. Blood test, reactions of inflammation and revelation of cytokine and immune cellswere methods for evaluating anti-inflammation effect. The tendency of experimental methods was to focus on molecular biologic method. 2. In theses related to pain relief, many clinical attempts with herbal injection were carried out, and Carthami Flos and Scolopendrawere used most. Observing reduction of pain inducing factor and checking behavioral change were methods for evaluating pain relief. 3. In theses related to obesity, research focused on effects in association with spots on the body suitable for acupuncture. There were also attempts comparing effectiveness between single injections and complex injections. Astraball Radix, Angelica Gigantis Radix, Coicis Semen and Taeumjowetang were used. Evaluation of anti-obesity effects were by weight loss, food efficiency, blood lipid profile and evaluation of liver function. 4. In theses related to safety of herbal-acupuncture, Herba Chelidonii Chaenonelis Fructus, Clematis Florida Thunb, Corydalidis Tuber, Paeoniae Radix, and Carthami Flos which marked 2 theses each were most studied. Methods of evaluating safety were mostly by observing liver and kidney functions based on blood test, and by applying herbal injections to clinical treatment. Conclusion : Herbal acupuncture is being used in various ways associating with its anti-inflammation, pain relief and anti-obesity effect. Studies on efficacy and mechanism of herbal acupuncture are being conducted even at the molecular biology level.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.10
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• pp.1459-1465
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• 2013

Two in vitro experiments were conducted to evaluate the effect of methylcellulose (MC) on i) bacterial detachment from rice straw as well as ii) inhibition of bacterial attachment and fiber digestibility. To evaluate the effect of MC on fibrolytic bacterial detachment (Exp 1), in vitro bacterial cultures with 0.1% (w/v) MC solution were compared with cultures without MC after 8 h incubation. The effect of MC on inhibition of bacterial attachment was determined by comparing with real-time PCR the populations of F. succinogenes, R. flavefaciens and R. albus established on rice straw pre-treated with 0.1% MC with those on untreated straw after incubation for 0, 6 and 12 h (Exp 2). The major fibrolytic bacterial attachment on rice straw showed significantly lower populations with either the addition of MC to the culture or pre-treated rice straw compared to controls (p<0.05). Also, the digestibility of rice straw with MC was significantly lower compared with control (p<0.05). The F. succinogenes population did not show detachment from rice straw, but showed an inhibition of attachment and proliferation on rice straw in accordance with a decrease of fiber digestion. The detachments of Ruminococcus species co-existed preventing the proliferations with subsequent reduction of fiber degradation by MC during the incubation. Their detachments were induced from stable colonization as well as the initial adhesion on rice straw by MC in in vitro ruminal fermentation. Furthermore, the detachment of R. albus was more sensitive to MC than was R. flavefaciens. These results showed the certain evidence that attachment of major fibrolytic bacteria had an effect on fiber digestion in the rumen, and each of fibrolytic bacteria, F. succinogenes, R. flavefaciens and R. albus had a specific mechanism of attachment and detachment to fiber.

• Nutritional Sciences
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• v.9 no.2
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• pp.124-130
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• 2006

To examine the effects of alcohol consumption on body fluid restoration and fat mobilization following exercise induced dehydration, nine healthy collegiate men ($24{\pm}2yrs,\;177{\pm}5cm,\;72{\pm}8kg,\;10.5{\pm}2.3%$ body fat) underwent three experiments. In each experiment, subjects ran on a treadmill to reduce individual body mass to $2.2{\pm}0.1%$ and consumed one of three beverages containing 0, 4, or 8% alcohol over 60 min followed by 4 hr of resting recovery. They consumed approximately 150% of weight loss $(2053{\pm}204,\;2091{\pm}149,\;and\;1943{\pm}295mL)$ and content of alcohol was $9.9{\pm}1.0(0%),\;71.9{\pm}5.1(4%)$, and $132.2{\pm}20.1g$ (8% trial). Body weight, urine volume and samples, blood samples, and thirst sensation were measured five times; at baseline, immediately after exercise, and 0, 1st, and 4th hr of recovery. Blood alcohol concentration after ingestion was $0.0{\pm}0.0(0%),\;0.1{\pm}0.02(4%)$, and $0.2{\pm}0.03%$ (8% trial). No differences in blood sodium and potassium concentrations, and urine specific gravity were noticed over time periods and trials. Thirst sensation tended to be elevated in all trials immediately after exercises and urine output was elevated during the recovery. The magnitude of changes in these variables was proportional to the alcohol concentrations, but not statistically significant. While serum osmolality was not different among trials and time periods in 0 and 4% trials, it was higher during recovery than the baseline in the 8% trial (P<0.01). Triglycerides did not change throughout the time period and among trials. Free fatty acids were elevated after exercise in all trials and 4th hr of recovery in 0% (P<0.05). Subjects' net body fluid balance at 4th hr of recovery was negatively maintained and proportional to alcohol concentrations. Only 8% trials showed a significant reduction at 1st and 4th hr of recovery compared to 0 hr. The results suggested that diuretic effect of alcohol after moderate level of dehydration appeared dose dependent, but beverage containing alcohol up to 4% did not induce impaired rehydration than alcohol free drinks. Alcohol effects on fat mobilization during recovery appeared to be minimal and the mechanism is unclear.

• BMB Reports
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• v.46 no.8
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• pp.422-427
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• 2013

Although BMP9 is highly capable of promoting osteogenic differentiation of mesenchymal stem cell (MSCs), the molecular mechanism involved remains to be fully elucidated. Here, we explore the possible involvement and detail role of JNKs (c-Jun N-terminal kinases) in BMP9-induced osteogenic differentiation of MSCs. It was found that BMP9 stimulated the activation of JNKs in MSCs. BMP9-induced osteogenic differentiation of MSCs was dramatically inhibited by JNKs inhibitor SP600125. Moreover, BMP9-activated Smads signaling was decreased by SP600125 treatment in MSCs. The effects of inhibitor are reproduced with adenoviruses expressing siRNA targeted JNKs. Taken together, our results revealed that JNKs was activated in BMP9-induced osteogenic differentiation of MSCs. What is most noteworthy, however, is that inhibition of JNKs activity resulted in reduction of BMP9-induced osteogenic differentiation of MSCs, implying that activation of JNKs is essential for BMP9 osteoinductive activity.

• Korean Chemical Engineering Research
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• v.45 no.5
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• pp.523-528
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• 2007

The objectives of this research are to investigate the mechanism of coagulation affecting UF, find out the effect of metal salt coagulant on membrane fouling. Either rapid mixing + UF or slow mixing + UF process caused much less flux decline. For PACl coagulant, the rate of flux decline was reduced for both hydrophilic and hydrophobic membrane than alum due to higher formation of flocs. In addition, the rate of flux decline for the hydrophobic membrane was significantly greater than for the hydrophilic membrane, regardless of pretreatment conditions. In general, Coagulation pretreatment significantly reduced the fouling of the hydrophilic membrane, but did little decrease the flux reduction of the hydrophobic membrane. When an Al(III) salt is added to water, monomers, polymers, or solid precipitates may form. Different Al(III) coagulants (alum and PACl) show to have different Al species distribution over a rapid mixing condition. During the rapid mixing period, for alum, formation of dissolved Al(III) (monomer and polymer) increases, but for PACl, precipitates of $Al(OH)_{3(s)}$ increases rapidly. This experimental results pointed out that precipitates of $Al(OH)_{3(s)}$ rather than dissolved Al(III) formation is major factor affecting flux decline for the membrane.

• Microbiology and Biotechnology Letters
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• v.41 no.1
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• pp.88-95
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• 2013

Candida biofilms are self-organized microbial communities growing on the surfaces of host tissues and medical devices. These biofilms have been displaying increasing resistance against conventional antifungal agents. The roots of Scutellaria baicalensis have been widely used for medicinal purpose throughout East Asia. The aim of the present study was to evaluate the effect of S. baicalensis aqueous extract upon the preformed biofilms of 10 clinical C. albicans isolates, and assess the mechanism of the antibiofilm activity. Its effect on preformed biofilm was judged using an XTT reduction assay and the metabolic activity of all tested strains were reduced ($57.7{\pm}17.3$%) at MIC values. The S. baicalenis extract inhibited (1, 3)-${\beta}$-D-glucan synthase activity. The effect of S. baicalensis on the morphology of C. albicans was related to the changes in growth caused by inhibiting glucan synthesis; most cells were round and swollen, and cell walls were densely stained or ruptured. The anticandidal activity was fungicidal, and the extract also arrested C. albicans cells at $G_0/G_1$. The data suggest that S. baicalensis has multiple fatal effects on target fungi, which ultimately result in cell wall disruption and killing by inhibiting (1, 3)-${\beta}$-D-glucan synthesis. Therefore, S. baicalensis holds great promise for use in treating and eliminating biofilm-associated Candida infections.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.12
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• pp.1262-1267
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• 2008

Reductive discolorization studies were conducted. Azo-dyes usually have biological toxicity and it is known that the dyes are hardly removed by biological treatments. One of the simplest way to remove the color is to break the azo-bond and it is possible to break the bond with zero-valent metals. Three types of azo-dyes (Cibacron Briliant Yellow 3G-P (CBY3G-P), Benzopurpurin 4b (B-4B), Chicago sky blue 6b (CSB6B)) were tested. All tested azo-dyes were highly pH dependent and lower pH was preferred. The reaction mechanism was reductive cleavage and amines were expected as products. The dissolved iron ions from zero-valent iron can also remove the color through coagulation and precipitation and a set of experiments were conducted to evaluate the contribution by the dissolved iron. The results indicated that the contribution were also dependent on the type of dyes. This study showed that the reductive cleavage using zero-valent iron could be an alternative for the azo-dye waste water.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.5
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• pp.397-405
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• 2001

The ryanodine receptor, a $Ca^{2+}$ release channel of the sarcoplasmic reticulum (SR), is responsible for the rapid release of $Ca^{2+}$ that activates cardiac muscle contraction. In the excitation-contraction coupling cascade, activation of SR $Ca^{2+}$ release channel is initiated by the activity of sarcolemmal $Ca^{2+}$ channels, the dihydropyridine receptors. Previous study showed that the relaxation defect of diabetic heart was due to the changes of the expressional levels of SR $Ca^{2+}$ATPase and phospholamban. In the diabetic heart contractile abnormalities were also observed, and one of the mechanisms for these changes could include alterations in the expression and/or activity levels of various $Ca^{2+}$ regulatory proteins involving cardiac contraction. In the present study, underlying mechanisms for the functional derangement of the diabetic cardiomyopathy were investigated with respect to ryanodine receptor, and dihydropyridine receptor at the transcriptional and translational levels. Quantitative changes of ryanodine receptors and the dihydropyridine receptors, and the functional consequences of those changes in diabetic heart were investigated. The levels of protein and mRNA of the ryanodine receptor in diabetic rats were comparable to these of the control. However, the binding capacity of ryanodine was significantly decreased in diabetic rat hearts. Furthermore, the reduction in the binding capacity of ryanodine receptor was completely restored by insulin. This result suggests that there were no transcriptional and translational changes but functional changes, such as conformational changes of the $Ca^{2+}$ release channel, which might be regulated by insulin. The protein level of the dihydropyridine receptor and the binding capacity of nitrendipine in the sarcolemmal membranes of diabetic rats were not different as compared to these of the control. In conclusion, in diabetic hearts, $Ca^{2+}$ release processes are impaired, which are likely to lead to functional derangement of contraction of heart. This dysregulation of intracellular $Ca^{2+}$ concentration could explain for clinical findings of diabetic cardiomyopathy and provide the scientific basis for more effective treatments of diabetic patients. In view of these results, insulin may be involved in the control of intracellular $Ca^{2+}$ in the cardiomyocyte via unknown mechanism, which needs further study.