• Journal of Chest Surgery
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• v.30 no.3
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• pp.253.1-262
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• 1997

Hypothermia during lung preservation decreases metabolic processes. After the rabbit lung was flushed with modified Euro-Collins solution, heart-lung block was harvested and the left lung was assessed after ligation of the right pulmonary artery and right main-stem bronchus. Heart-lung block was immersed in the same solution for 6 hours. The modified Euro-Collins solution and storage temperature of group 1(10 cases) was 4t, roup 2(10 cases) was l$0^{\circ}C$. On completion of the storage period, the left lung was ventilated and reperfused with blood u:high used a cross-circulating paracorporeal rabbit as a "biologic deoxygenator" for 60 minutes. Pulmonary artery pressure, airway pressure, difference in oxygen tension between mow and outflow perfusate and degree of pulmonary edema were assessed at 10-minute intervals while the left lung was ventilated at 0.8 of the inspired oxygen fraction. The mean pulmonary venous oxygen tensions at 10 and 60 minutes after reperfusion were 209.52$\pm$42.46 and 103.48$\pm$ 15.96 mmHg in group I versus 247.78$\pm$36.19 and 147.91 $\pm$ 11.07 mmHg in group II(p=0.049, (0.0001). The mean alveolar-arterial oxygen differences at 20 and 60 minutes after reperfusion were 357. 95$\pm$ 12.84 and 437.31 14.26 mmHg in group I versus 310.88$\pm$3).47 and )90.93$\pm$ 15.86 mmHg in group II (p=0.0092, (0.0001). The mean pulmonary arterial pressures at 10 and 60 minutes after reperfusion were 40.56$\pm$ 18.66 and 87. 2$\pm$ 17.22 mmHg in group I versus 31.22$\pm$6.84 and 65.78$\pm$ 11.02 mmHg in group rl (p : 0.048, 0.0062). The mean pulmonary vascular resistances at 10 and 60 minutes after reperfusion were 2.69$\pm$0.85 and 4.36$\pm$0.86 mmHg/ml/min in group I versus 1.99$\pm$0.39 and 3.29$\pm$0.55 mmHg/ml/min in group II(p : 0.0323, 0.0062). There were no difference between groups in peak airway pressure, lung compliance and degree of pulmonary edema. In conclusion that preservation of lung at l$0^{\circ}C$ was superior to preservation at 4$^{\circ}C$.}C$.

• Journal of Animal Science and Technology
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• v.55 no.1
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• pp.67-74
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• 2013

To know the emission amount of greenhouse gases from bedding materials of cowshed floor, the emission rates of methane ($CH_4$) and nitrous oxide ($N_2O$) gases from a simulated cowshed floor (SCF) with sawdust that manure loading rate into the bedding material could be accurately controlled were assessed in this study. The manure loading rates of Korean beef and Holstein dairy cattle into the SCF of $0.258m^2$ surface area with 10 to 15 cm height sawdust were $1.586kg/m^2/d$ and $3.588kg/m^2/d$, respectively, and those were calculated on the basis of "Standard model for sustainable livestock" and "Data for excretion amount of manure from livestock". All experiments were done in triplicates in three different seasons (May to July, Sep. to Nov., and Feb. to Apr.) using 12 SCFs. The effects of bedding material thickness on $CH_4$ and $N_2O$ emission from SCFs for both Korean beef cattle and Holstein dairy cattle were not statistically significant (p<0.05). Emission amount of $CH_4$ and $N_2O$ per square meter of SCF for Holstein dairy cattle was 7.5 and 1.2 times higher than that of Korean beef cattle, respectively. The yearly $CH_4$ amount per head was 17.7 times higher in Holstein dairy cattle, obtaining 130.4 g/head/year from SCF for Holstein dairy cattle and 7.4 g/head/year from SCF for Korean beef cattle, and $N_2O$ was also 3.8 times higher in Holstein dairy cattle (3,267 g/head/year in Korean beef cattle and 14,719 g/head/year in Holstein dairy cattle). However, the $N_2O$-N per loaded nitrogen into SCF was higher in Korean beef cattle, having 0.2148 and 0.1632 kg $N_2O$-N/kg N in Korean beef cattle and Holstein dairy cattle, respectively, and those values were 3.07 and 2.33 times higher than that of Intergovernmental Panel on Climate Change (IPCC) 2006 guideline (GL) (0.07 kg $N_2O$-N/kg N).

• Journal of the Korean Applied Science and Technology
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• v.37 no.2
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• pp.153-161
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• 2020

Arthrospira platensis is the oldest marine microalgae on the planet, is said to contain most of the nutrients needed by the human body. It's components are reported to contain a large amount of various substances such as phycocyanin, chlorophyll and β-carotene, and are known to have an aging and whitening effect. In this study, UVB-induced reactive oxygen species reduction efficacy and antioxidant activity of spirulina purified water extract were investigated. effect was confirmed by measuring DPPH radical scavenging activity, FRAP reducing power and ABTS⁺ radical scavenging activity of 0.05, 0.10, 0.50 1.0 mg/mL of spirulina purified water extract. The coagulation rate, hatching rate and heart rate toxicity were measured by treating spirulina purified water extract with 0.05, 0.10, 0.50 mg/mL concentration using Zebrafish, an alternative experimental animal model. UVB-induced ROS measurement was treated with spirulina extract at 0.05, 0.10, 0.50 mg/mL concentration, and then stained with DCFH-DA to confirm the inhibitory effect of ROS. As a result of measuring antioxidant effect, DPPH, FRAP and ABTS⁺ showed concentration-dependent antioxidant effects in comparison with ascorbic acid. and measuring the coagulation rate, hatching rate, and heart rate using Zebrafish, an alternative experimental animal, it was confirmed that there was no toxicity in 0.05 and 0.10 mg/mL except 0.5 mg/mL compared to the control group. The ROS scavenging activity of UVB-induced zebrafish showed higher ROS reduction than the positive control. The results of this study suggest that spirulina and purified water extracts are valuable for UV and skin protection cosmetics.

• Journal of Chest Surgery
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• v.42 no.4
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• pp.409-417
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• 2009

Background: Glutaraldehyde-fixed heterografts are prone to calcification after long-term implantation in human, and this is one of the limiting factors for the longevity of the heterografts used in cardiovascular surgery. The aim of the study was to evaluate the anticalcification effect of an ethanol and amino acids treatment on glutaraldehyde-fixed bovine pericardium. Material and Method: Bovine pericardial tissues were divided into 5 groups. Group 1 consisted of tissues fixed with glutaraldehyde, group 2 consisted of commercially available bovine pericardial valve tissues (Carpentier-Edwards PERIMOUNT), group 3 consisted of glutaraldehyde-fixed tissues treated with ethanol, group 4 consisted of glutaraldehyde-fixed tissues treated with ethanol and L-glutamic acid, and group 5 consisted of glutaraldehyde-fixed tissues treated with ethanol and homocysteic acid. The tissue microstructure was examined by light and electron microscopy. Tissue samples of each group were implanted into rat subcutaneous tissue for 3 $\sim$ 4 months and the calcium contents were measured after harvest. Result: The collagen fibers appeared to be well preserved in all the groups. The calcium contents of groups 2, 3, 4 and 5 (13.46$\pm$11.74, 0.33$\pm$0.02, 0.39$\pm$0.08 and 0.42$\pm$0.06 $\mu$g/mg, respectively) were all significantly lower than that of group 1 (149.97$\pm$28.25 $\mu$g/mg) (p<0.05). The calcium contents of groups 3, 4 and 5 were all significantly lower than that of group 2 (p<0.05). Conclusion: Treatment with ethanol alone or in combination with amino acids (L-glutamic acid or homocysteic acid) strongly prevented the calcification of glutaraldehyde-fixed bovine pericardium.

• The korean journal of orthodontics
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• v.40 no.1
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• pp.16-26
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• 2010

Objective: The purposes of this study were to evaluate the force and stress depending on the type, deflection and thickness of the materials and to evaluate the mechanical properties of thermoplastic materials after repeated loading. Methods: Four types of thermoplastic products were tested. Force until the deflections of 2.0 mm and the stress when the materials were restoring to its resting position were evaluated. The mechanical properties of thermoplastic materials evaluated after 5 repeated loading cycles. Results: The interaction was observed between the thickness and the deflection (p < 0.05) from the regression equation. Thickness and amount of deflection rather than products and materials showed the largest effect on force and stress. In all products, at least 159 gf of force was required for more than 1.0 mm deflection or when materials with 1.0 mm thickness were deflected. The stress recorded was more than 19 gf/$mm^2$. During repeated loading, each group showed significant difference on the force and the stress (p < 0.01), 10 - 17% reduction of force and 4 - 7% reduction of stress in average. Conclusions: Proper thickness of thermoplastic materials and deflection level of tooth movement should be decided for the physiologic tooth movement. Force decay after repeated loading should be considered for the efficient tooth movement.

• KSBB Journal
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• v.24 no.1
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• pp.30-40
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• 2009

Statistical optimization of the production medium was carried out in order to find an optimal medium composition in itaconic acid fermentation process. Itaconic acid utilized in the manufacture of various synthetic resins is a dicarboxylic acid biosynthesized by fungal cells of Aspergillus terreus in a branch of the TCA cycle via decarboxylation of cis-aconitate. Through OFAT (one factor at a time) experiments, six components (glucose, fructose, sucrose, soluble starch, soybean meal and cottonseed flour) were found to have significant effects on itaconic production among various carbon- and nitrogen-sources. Hence, using these six factors, interactive effects were investigated via fractional factorial design, showing that the initial concentrations of sucrose and cottonseed flour should be high for enhanced production of itaconic acid. Furthermore, through full factorial design (FFD) experiments, negative effects of $KH_2PO_4$ and $MgSO_4$ on itaconic acid biosynthesis were demonstrated, when excess amounts of the each component were initially added. Based on the FFD analysis, further statistical experiments were conducted along the steepest ascent path, followed by response surface method (RSM) in order to obtain optimal concentrations of the constituent nutrients. As a result, optimized concentrations of sucrose and cottonseed flour were found to be 90.4g/L and 53.8g/L respectively, with the corresponding production level of itaconic acid to be 4.36 g/L (about 7 fold higher productivity as compared to the previous production medium). From these experimental results, it was assumed that optimum ratio of the constituent carbon (sucrose) and nitrogen (cottonseed flour) sources was one of the most important factors for the enhanced production of itaconic acid.

• Korean Journal of Food Science and Technology
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• v.52 no.4
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• pp.369-376
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• 2020

The purpose of this study was to evaluate the antioxidant components and activities of HR02/04(8:2)-W, a mixture of S. quelpaertensis Nakai and F. erecta var. sieboldii. We investigated the p-coumaric acid, total flavonoid, and total phenol contents. To evaluate the antioxidant efficacy, we measured the 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzthiazoline6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity, FRAP activity, reducing power, and ORAC value. We observed the protective effect of hydrogen peroxide against cell damage in human dermal fibroblasts. As a result of the experiment, the p-coumaric acid, total flavonoid, and total phenol contents were 75.62±1.56 mg/100 g, 21.57±0.84 mg rutin equivalent (RE)/g, and 21.25±1.31 mg gallic acid equivalent (GAE)/g, respectively. In the experiments on antioxidant activity, HR02/04(8:2)-W was found to have significantly increased antioxidant activity. In the human dermal fibroblasts, the HR02/04(8:2)-W treated groups could effectively protect cells against oxidative damage. In this study, we confirmed that HR02/04(8:2)-W is a material with effective physiological antioxidant activity.

• Journal of Internet Computing and Services
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• v.18 no.1
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• pp.77-88
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• 2017

Recently, with the advent of knowledge based society where information and knowledge make values, patents which are the representative form of intellectual property have become important, and the number of the patents follows growing trends. Thus, it needs to classify the patents depending on the technological topic of the invention appropriately in order to use a vast amount of the patent information effectively. IPC (International Patent Classification) is widely used for this situation. Researches about IPC automatic classification have been studied using data mining and machine learning algorithms to improve current IPC classification task which categorizes patent documents by hand. However, most of the previous researches have focused on applying various existing machine learning methods to the patent documents rather than considering on the characteristics of the data or the structure of patent documents. In this paper, therefore, we propose to use two structural fields, technical field and background, considered as having impacts on the patent classification, where the two field are selected by applying of the characteristics of patent documents and the role of the structural fields. We also construct multi-label classification model to reflect what a patent document could have multiple IPCs. Furthermore, we propose a method to classify patent documents at the IPC subclass level comprised of 630 categories so that we investigate the possibility of applying the IPC multi-label classification model into the real field. The effect of structural fields of patent documents are examined using 564,793 registered patents in Korea, and 87.2% precision is obtained in the case of using title, abstract, claims, technical field and background. From this sequence, we verify that the technical field and background have an important role in improving the precision of IPC multi-label classification in IPC subclass level.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.5
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• pp.511-519
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• 2008

Statement of problem: An incompatibility between the initiator systems of self-curing composite resins and light-curing adhesives was supposed recently. Purpose: The purpose of the study was to evaluate the influence of activators for self/dual bonding on dentin shear bonding strengths. Material and methods: Fifty human molars were divided into 5 groups. A flat dentin surface was created for each tooth. A self-curing composite resin (Luxacore) was bonded with the following adhesives (n = 10); One-Step, Prime&Bond NT, AdheSE, Prime&Bond NT and AdheSE were also used in combination with activators. Shear bond strengths were measured after 24 hours of water storage. The specimens were loaded in shear in the Instron until failure at a 1 mm/min crosshead speed. Data were compared using one-way ANOVA and Tukey HSD test (${\alpha}$= 0.05). Results: The dentin adhesive systems in order of decreasing median bond strength were One-Step > Prime&Bond NT with activator, AdheSE with activator > Prime&Bond NT, AdheSE. Among adhesives, One-Step had the highest bond strength. Prime&Bond NT with activator had higher bond strengths than Prime&Bond NT that was used alone, and so was AdheSE. Conclusion: Shear bond strengths were increased in Prime&Bond NT and AdheSE when these were used with activators comparing used without activators. But using activators was not effective clinically comparing One-Step.

• Progress in Medical Physics
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• v.21 no.2
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• pp.201-208
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• 2010

Recently, along with technology development of endoscopic equipment, a stent has been developed for the convenience of operation, shortening of recovery times, and reduction of patient's pain. To this end, optimal factors are simulated for the stent structure and mechanical reaction and verified using finite element analysis. In order to compare to present commercialized product such as Zilver (Cook, Bloomington, Indiana, USA) and S.M.A.R.T (Cordis, Bridgewater Towsnhip, New Jersey, USA), mechanical impact factors were determined through Taguchi factor analysis, and flexibility and expandability of all the products including ours were tested using finite element analysis. Also, important factors were sought that fulfill the optimal condition using central composition method of response surface analysis, and optimal design were carried out based on the important factors. From the centra composition method of Response surface analysis, it is found that importat factors for flexibility is stent thickness (T) and unit area (W) and those for expandability is stent thickness (T). In results, important factors for optimum condition are 0.17 mm for stent thickness (T) and $0.09\;mm^2$ for unit area (W). Determined and verified by finite element analysis in out research institute, a stent was manufactured and tested with the results of better flexibility and expandability in optimal condition compared to other products. Recently, As Finite element analysis stent mechanical property assessment for research much proceed. But time and reduce expenses research rarely stent of optimum coditions. In this research, Important factor as mechanical impact factor stent Taguchi factor analysis arrangement to find flexibility with expansibility as Finite element analysis. Also, Using to Center composition method of Response surface method appropriate optimized condition searching for important factor, these considering had design optimized. Production stent time and reduce expenses was able to do the more coincide with optimum conditions. These kind of things as application plan industry of stent development period of time and reduce expenses etc. be of help to many economic development.