• Journal of Life Science
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• 제23권1호
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• pp.15-23
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• 2013

AprE51 from Bacillus amyloliquefaciens CH51 is a 27 kDa subtilisin-like protease with fibrinolytic activity. AprE51-6 showing increased catalytic activity was produced previously. To enhance the thermostability of AprE51-6, 2 residues, Gly-166 and Asn-218 based on B. subtilis subtilisin E were mutated by site-directed mutagenesis. The results of the mutational analysis showed that substitution of arginine for Gly-166 (AprE51-7) increased the fibrinolytic activity 1.8-fold. An N218S mutant (AprE51-8) also increased the fibrinolytic activity up to 4.5-fold in a fibrin plate assay. Purified AprE51-7 and AprE51-8 mutants had a 1.9- and a 2.5-fold higher $k_{cat}$, respectively, and a 2.1-1.9-fold lower $K_m$, respectively. This resulted in a 3.8- and a 4.7-fold increase in catalytic efficiency ($k_{cat}/K_m$), respectively, relative to that of wild-type AprE51. AprE51-8 had a broader pH range than AprE51-6 and nattokinase, especially at an alkaline pH value. In addition, AprE51-8 showed higher thermostability than AprE51-6 at $60^{\circ}C$. The half-lives of AprE51-7 and AprE51-8 at $50^{\circ}C$ were 21.5 and 27.3 min, respectively, which are 2.0 and 2.6 times longer, respectively, than that of the wild-type AprE51.

• Food Science and Preservation
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• 제16권5호
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• pp.734-741
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• 2009

Response surface methodology (RSM) was used to optimize extraction conditions for functional components of buckwheat (Fagopyrum esculentum). A central composite design was applied to investigate the effects of three independent variables, namelyextraction temperature (X1), extraction time (X2), and ethanol concentration (X3), on responses including extraction yield (Y1), total phenolic content in the extract (Y2), $\alpha$-glucosidase inhibition activity (Y3), and acetylcholine esterase (ACE) inhibition activity (Y4). Data were analyzed using an expert design strategy and statistical software. The maximum yield was 24.95% (w/w) at $55.75^{\circ}C$ extraction temperature, 8.75 hextraction time, and 15.65% (v/v) ethanol. The maximum total phenolic yield was 222.45 mg/100 g under the conditions of $28.11^{\circ}C$ extraction temperature, 8.65 h extraction time, and 81.72% (v/v) ethanol. The maximum $\alpha$-glucosidase inhibition activity was 85.38% at $9.62^{\circ}C$, 7.86 h, and 57.58% (v/v) ethanol. The maximum ACE inhibition activity was 86.91% under extraction conditions of $10.12^{\circ}C$, 4.86 h, and 44.44% (v/v) ethanol. Based on superimposition of a four-dimensional RSM with respect to levels of total phenolics, $\alpha$-glucosidase inhibition activity, and ACE inhibition activity, obtained under various extraction conditions, the optimum ranges of conditions were an extraction temperature of $0-70^{\circ}C$, an extraction time of 2-8 h, and an ethanol concentration of 30-80% (v/v).

• Journal of the Korean Society of Food Science and Nutrition
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• 제35권1호
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• pp.15-20
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• 2006

The water and $40\%$ ethanol extracts from mulberry fruits were tested for their antimicrobial activities against Helicobacter pylori and antioxidant. Kangwon III (Morus albba L.) was higher phenolic content (2.90 mg/g) than other water extracts. The phenolic contents of $40\%$ ethanol extracts from Kangwon III and Hihak were 3.02 mg/g and 2.46 mg/g, respectively . The ABTS [2,2'-azinobis(3-ethylbenzothiazoline-6-sulfornic acid)] radical decolorization, electron donating ability (EDA), thiobarbituric acid reactive substance (TBARS) and antioxidant protection factor (PF) were determined for water extracts and $40\%$ ethanol extracts from mulberry fruits. EDA was higher in water extracts than ethanol extract. EDA of water extract from Kangwon III was determined as $99.54\%$ while the activity of ethanol extracts was $89.61\%$ in Daechoukmyeun. The water extracts from Cheongilppong showed higher antioxidative activity than another mulberry fruits extract when evaluated by ABTS [2,2'-azinobis(3-ethylbenzothiaznoline-6-sulfornic acid)] radical decolorization, TBARS and antioxidant PF by water extracts. Kangwon III was higher phenolic content (2.90 mg/g) than other that of water extracts. $40\%$ ethanol extracts were determined that phenolic contents of Kangwon III, Hihak were 3.02 mg/g, 2.46 mg/g for each other. Antimicrobial activity showed the high value in water extracts of Cheongilppong, Kuksang 20. The result will be useful nature microbial medicine for mulberry fruits.

• Restorative Dentistry and Endodontics
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• 제31권4호
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• pp.312-322
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• 2006

The objectives of this study were to evaluate the effect of surface roughness on the surface color and translucency of the composite resins. Two composite resins (Esthet-X, Dentsply, Milford, USA and Charisma, Kulzer, Domagen, Germany) were used to investigate the surface color. Charisma was used to investigate the translucency. 40 disc samples (diameter: 8 mm, thickness: 5 mm) were made by each product to measure the surface color. Polymerized each sample's one side was treated by Sof-Lex finishing and polishing system (Group C, M, F, SF). 40 disc samples (diameter: 6 mm, thickness: 1 mm) were prepared to measure the opacity. 1 mm samples were ground one side with #600, #1000, #1500 and #2000 sandpapers. CIE $L^{*}a^{*}b^{*}$ values of each 5 mm thickness samples, and XYZ values of 1 mm thickness samples on the white and black background were measured with spectrophotometer (Spectrolino, GretagMacbeth, Regensdorf, Switzerland). Mean surface roughness (Ra) of all samples before and after surface treatment was measured using the Surface Roughness Tester SJ-301 (Mytutoyo, Tokyo, Japan). Regardless of type and shade of the composite resin, $L^{*}$ values measured in group C were higher than others (p < 0.05), and $L^{*}$ value decreased as the Ra value decreased except B3 shade of Esthet-X. But there were no significant difference in $a^{*}$ values among groups. In control group and SF, highest $b^{*}$ values were measured (p < 0.05), except B1 shade of Esthet-X. Contrast ratio decreased as the Ra value decreased (p < 0.05). With the above results, difference of surface roughness has influence on surface color and translucency of dental composite resins.

• Korean Journal of Poultry Science
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• 제43권2호
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• pp.111-118
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• 2016

Mycotoxins are secondary metabolites produced by molds, such as Aspergillus, Fusarium and Penicillium, that have adverse effects on animals and humans. Aflatoxin, ochratoxin, zearalenone, fumonisin and deoxynivalenol are the mycotoxins of greatest agro-economic importance and cause acute disease called mycotoxicoses. Mycotoxicosis in poultry birds results in decreased meat/egg production, immunosuppressant, and hepatotoxicosis. Some of toxins or their metabolites may be retained in animal or human tissues and induce health problems. This study was designed to develop a sensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the simultaneous detection and quantification of mycotoxins, such as aflatoxin $B_1$, aflatoxin $M_1$, ochratoxin A, zearalenone, fumonisin B and deoxynivalenol, in chicken liver and kidney tissues. The mycotoxins were extracted and purified using modified QUECHERS methods, separated by LC and detected by an electrospray ionisation interface (ESI) and tandem MS. Good precision and linearity were observed for most of six mycotoxins. The recovery test for each mycotoxin in liver and kidney tissues mostly indicated good average recovery rates between 80.94% and 98.10% and the coefficient of variation mostly under 13.78%, except for aflatoxin $M_1$ and fumonisin $B_1$. The limit of detection (LOD) for six mycotoxins was $7.6{\sim}145.79{\mu}g/kg$ in liver tissues and $6.07{\sim}197.20{\mu}g/kg$ in kidney tissues. The quantification limits (LOQ) for 6 mycotoxins were in the range $23.04{\sim}441.78{\mu}g/kg$ in liver tissues and $18.40{\sim}597.59{\mu}g/kg$ in kidney tissues, respectively. The developed multi-mycotoxin method in this study permits simultaneous, simple, and rapid determination of several co-existing mycotoxins in chicken liver and kidney tissues.

• The Korean Journal of Nuclear Medicine
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• 제39권1호
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• pp.21-25
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• 2005

Purpose: $^{14}C$-urea breath test (UBT) is a non-invasive and reliable method for the diagnosis of Helicobacter pylori (HP) infection. In this study, we evaluated the diagnostic performance of a new and rapid $^{14}C$-UBT (Heliprobe method), which was equipped with $Geiger-M\ddot{u}ller$ counter and compared the results with those obtained by using the conventional method. Materials and Methods: Forty-nine patients with dyspepsia underwent gastroduodenoscopy and $^{14}C$-UBT. A 37 KBq $^{14}C$-urea capsule was administered to patients and breath samples were collected. In Heliprobe method, patients exhaled into a Hellprobe BreathCard for 10 min. And then the activities of the BreathCard were countered using Heliprobe analyzer. In the conventional method, results were countered using liquid scintillation counter. During gastroduodenoscopy, 18 of 49 patients were underwent biopsies. According to these histologic results, we evaluated the diagnostic performance of two different methods and compared them. Also we evaluated the concordant and disconcordant rates between them. Results: In all 49 patients, concordant rate of both conventional and Heliprobe methods was 98% (48/49) and the discordant rate was 2% (1/49). Thirteen of 18 patients to whom biopsies were applied, were found to be HP positive on histologic results. And both Heliprobe method and conventional method classified 13 of 13 HP-positive patients and 5 of 5 HP-negative patients correctly (sensitivity 100%, specificity 100%, accuracy 100%). Conclusion: The Heliprobe method demonstrated the same diagnostic performance compared with the conventional method and was a simpler and more rapid technique.

• Horticultural Science & Technology
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• 제33권1호
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• pp.47-54
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• 2015

This research was conducted to investigate the changes in moisture retention capacities of expanded rice-hull (ERH)-based root media and their influences on the growth of mother and daughter plants in vegetative propagation of 'Seolhyang' strawberry. The proportion of water at the container capacity of ERH medium was in the range of 20 to 23%. This range was lower than the 60 to 66% of strawberry-specialized medium, the 30 to 34% of soil mother material (SMM) and the 30 to 35% of loamy sand. The moisture content of ERH was reduced to 10 to 12% at 8 hours after irrigation, and there were large variations among replications of ERH medium. Among four kinds of root media formulated to contain ERH, the medium of ERH + coir dust (CD) (55 + 45%, v/v) had 26.5 and 32.5% water contents at 20 and 40 days after irrigation to daughter plants, respectively. The m edia o f ERH + sandy loam (S L) and E RH + S MM showed similar trends i n moisture r etention. The pH and EC i n the all root media tested were in the range of 6.7 to 7.1 and 0.03 to $0.08dS{\cdot}m^{-1}$, respectively. The pHs and ECs measured at 20 and 40 days after irrigation were not significantly different in each root medium. Among the root media formulated to contain ERH, the growth of daughter plants was the highest in the treatment of ERH + SL (55 + 45%, v/v). As the blending rate of coir dust was elevated in the ERH + CD media, moisture retention capacity increased gradually, but the growth of daughter plants became worse even though the medium showed higher moisture retention capacity than other root media tested. The growth of roots and aboveground tissues of daughter plants deteriorated in the root media formulated by blending ERH + perlite (PE) at various ratios. The results of this research suggest the optimum formulations of root media and management of moisture content in raising of strawberry daughter plants when ERH is a component of root media.

• Journal of Korean Philosophical Society
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• 제114호
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• pp.177-212
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• 2016

Kants Begriff der Freiheit des Willens ist sehr kompliziert und verwirrend. Denn sowie es Ziel der ${\gg}$Kritik der praktischen Vernunft${\ll}$ ist, die reine praktische Vernunft zu beweisen, liegt der Fokus von Kants Begriff der Freiheit auf der Freiheit von Zwang, wobei Kant eine unbestimmte Haltung zur Freiheit von Notwendigkeit einnimmt und sie dann $schie{\ss}lich$ leugnet. Leibnizens Begriff der Freiheit dagegen hebt die Freiheit von Notwendigkeit hervor, denn er sagt, dass der menschliche Wille nicht nur vom Zwang der Leidenschaft, sondern auch von Notwendigkeit frei sei. Die Struktur von Leibnizens Freiheitslehre unterscheidet sich zwar sehr von der Kants, aber die Charakterlehren beider Denker, in denen die $M{\ddot{o}}glichkeit$ der Vereinbarkeit von Freiheit und Notwendigkeit behandelt werden, weisen viele Parallelen auf. Zudem ist Leibnizens Begriff der Freiheit sehr eindeutig. Daher ist ein Vergleich von Leibnizens und Kants Begriff der Freiheit nicht nur sinnvoll und $f{\ddot{u}}hrt$ zu einem besserem $Verst{\ddot{a}}ndnis$ von Kants Freiheitsbegriff, durch die vergleichende Analyse stellt sich zudem auch heraus, dass auch bei Kant nicht nur Freiheit von Zwang, sondern auch Freiheit von Notwendigkeit $m{\ddot{o}}glich$ ist. Leibniz geht $f{\ddot{u}}r$ seine Freiheitslehre von dem Begriff der Freiheit vom Zwang der Leidenschaft, welcher von allen Rationalisten anerkannt wird, sowie von dem Begriff der Freiheit von der Notwendigkeit, welcher von Spinoza negiert wird, aus. Kant dagegen definiert Freiheit als $Unabh{\ddot{a}}ngigkeit$ von den Naturgesetzen, was diesen Begriff von Anfang an unklar macht. Kant war sich anfangs der Zweideutigkeit dieses Konzepts nicht $bewu{\ss}t$ und hat es undeutlich gebraucht, doch in der Neuauflage von ${\gg}$Die Religion innerhalb der $blo{\ss}en$ Vernunft${\ll}$ erkennt er den Unterschied in den zwei Begriffen der Willensfreiheit, weshalb er bei der Rechtslehre in der ${\gg}$Metaphysik der Sitten${\ll}$ dazu kommt, die Wahlfreiheit zu negieren. Aber in den Abschnitten, wo Kant in der ${\gg}$Kritik der reinen Vernunft${\ll}$ und der ${\gg}$Kritik der praktischen Vernunft${\ll}$ die Vereinbarkeit von Freiheit und Notwendigkeit behandelt, $f{\ddot{u}}hrt$ Kant aus, so wie auch Leibniz, dass der intelligible Charakter des Menschen sich durch wiederholte freie Wahl formt, womit sich $best{\ddot{a}}tigt$, dass auch Kant die Freiheit der Wahl anerkannt hat. Kant leugnet die Wahlfreiheit, weil er der Ansicht ist, dass der Begriff der Freiheit als ein einheitlicher Begriff definiert werden muss. Doch Freiheit muss nicht zwingend einheitlich definiert werden. Da Freiheit von Zwang und Freiheit von Notwendigkeit nicht $widerspr{\ddot{u}}chliche$ Begriffe sind, $k{\ddot{o}}nnen$ sie dem selben Willen gleichzeitig zugeteilt werden. Auch wird erst hierdurch Autonomie $m{\ddot{o}}glich$ gemacht.

• Journal of Space Technology and Applications
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• 제1권3호
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• pp.283-301
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• 2021

In order to satisfy the intellectual curiosity of mankind to explore the unknown, National Aeronautics and Space Administration (NASA) in the United States and European Space Agency (ESA) in Europe are embarking on various R&D under the motto of the grand dream of pioneering space into a safe and sustainable environment. In the 2020s and 30s, it is expected that advanced giant observation equipment will be in operation, such as the development of a 10-meter-class telescope in space. In Korea, following the development of the 0.15 m Near-Infrared Imaging Spectrometer (NISS), Korea Astronomy and Space Science Institute (KASI) is also participating a 0.2 m Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer (SPHEREx) as an international cooperation partner in small exploration telescope. However, domestic experience in the development and operation of the space telescopes is still insufficient, and there is no plan with long-term prospects for constructing telescopes. In order to answer questions about the unknown world that mankind has not experienced using our own equipment, planning and preparation for the construction of a space telescope through close cooperation among industry-university-institute-government is urgently needed. In this paper, the necessity, background, development goals, and expected effects of the development of the Korean Space Telescope are summarized conceptually, and a working group (WG) is also proposed. In the WG activities, Korea shall take the lead in establishing the Korean-style space telescope development plan, and will start a valuable step to establish the national direction in the field of space astronomy and related technologies. We hope that the WG will be another milestone in Korea's space development.

• Journal of Practical Agriculture & Fisheries Research
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• 제16권1호
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• pp.193-206
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• 2014

The objectives of the project are to increase farmers' income through GAP and to reduce the loss of agricultural produce, for which the Korean partner takes a role of transferring needed technologies to the project site. To accomplish the project plan, it is set to implement the project with six components: construction of buildings, installation of agricultural facilities, establishment of demonstration farms, dispatching experts, conducting training program in Korea and provision of equipments. The Project Management Committee and the Project Implementation Team are consisted of Korean experts and senior officials from Department of Agriculture, Myanmar that managed the project systematically to ensure the success of the project. The process of the project are; the ceremony of laying the foundation and commencing the construction of training center in April, 2012. The Ribbon Cutting Ceremony for the completion of GAP Training Center was successfully held under PMC (MOAI, GAPI/ARDC) arrangement in SAl, Naypyitaw on June 17, 2012. The Chairman of GAPI, Dr. Sang Mu Lee, Director General U Kyaw Win of DOA, officials and staff members from Korea and Myanmar, teachers and students from SAl attended the ceremony. The team carried out an inspection and fixing donors' plates on donated project machineries, agro-equipments, vehicles, computers and printer, furniture, tools and so forth. Demonstration farm for paddy rice, fruits and vegetables was laid out in April, 2012. Twenty nine Korean rice varieties and many Korean vegetable varieties were introduced into GAP Project farm to check the suitability of the varieties under Myanmar growing conditions. Paddy was cultivated three times in DAR and twice in SAl. In June 2012, vinyl houses were started to be constructed for raising seedlings and finished in December 2012. Fruit orchard for mango, longan and dragon fruit was established in June, 2012. Vegetables were grown until successful harvest and the harvested produce was used for panel testing and distribution in January 2013. Machineries for postharvest handling systems were imported in November 2012. Setting the washing line for vegetables were finished and the system as run for testing in June 2013. New water tanks, pine lines, pump house and electricity were set up in October 2013.