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Effect of Probiotics on Risk Factors for Human Disease: A Review (인간 질병의 위험 요인에 대한 Probiotics의 효과: 총설)

  • Chon, Jung-Whan;Kim, Dong-Hyeon;Kim, Hyun-Sook;Kim, Hong-Seok;Hwang, Dae-Geun;Song, Kwang-Young;Yim, Jin-Hyuk;Choi, Dasom;Lim, Jong-Soo;Seo, Kun-Ho
    • Journal of Dairy Science and Biotechnology
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    • v.32 no.1
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    • pp.17-29
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    • 2014
  • GRAS probiotics can be used to modulate intestinal microbiota and to alleviate various gastrointestinal disorders. In several recent studies, researchers have explored the potential expansion and usability of probiotics to reduce the risk factors associated with diseases, including obesity, hypercholesterolemia, arterial hypertension, hyperhomocysteinemia, and oxidative stress. In this review, our aim was to clarify the mechanism underlying interactions between hosts (animal or human) and probiotics and the beneficial effects of probiotics on human health.

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Study on the Biodegradability of Dispersants and Dispersant/Bunker-C Oil Mixtures and the Dissolved Oxygen Consumption in the Seawater(II) - The Biodegradability of Dispersant/Bunker-C Oil Mixtures and the Dissolved Oxygen Consumption in the Seawater - (해수중에서 유처리제 및 유처리제/Bunker-C유 혼합물의 생분해도와 용존산소소비에 관한 연구(II) - 유처리제/Bunker-C유 혼합물의 생분해도와 용존산소소비 -)

  • KIM Gwang-Su;PARK Chung-Kil;KIM Jong-Gu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.26 no.6
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    • pp.519-528
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    • 1993
  • The biodegradation experiment, the TOD analysis and the element analysis for dispersant, Bunker-C and dispersant/Bunker-C oil mixtures were conducted for the purposes of evaluating the biodegradability of dispersnat/Bunker-C oil mixtures and studying the consumption of dissolved oxygen with relation to biodegradation in the seawater. The results of biodegradation experiment showed the mixtures with $1:10{\sim}5:10$ mix ratios of dispersant to 4mg/l of Bunker-C oil to be $0.34{\sim}2.06mg/l$ of $BOD_5$ and to be $1.05{\sim}5.47mg/l$ of $BOD_{20}$ in natural seawater. The results of TOD analysis showed 1mg of Bunker-C oil to be 3.16mg of TOD. The results of element analysis showed the contents of carbon and hydrogen to be $87.3\%\;and\;11.5\%$ for Bunker-C oil, respectively, but nitrogen element was not detected in Bunker-C oil. The biodegradability of dispersant/Bunker-C oil mixture shown as the ratio of $BOD_5$/TOD was increased from $3\%\;to\;11\%$ as a mix ratio of dispersant to 4mg/l of Bunker-C oil changed from 1:10 to 5:10, and the mixtures were found to belong in the organic matter group of low-biodegradability. The deoxygenation rates($K_1$) and ultimate oxygen demands($L_o$) obtained through the biodegration experiment and Thomas slope method were found to be $0.072{\sim}0.097/day$ and $1.113{\sim}6.746mg/l$ for the mixtures with $1:10{\sim}5:10$ mix ratios of dispersant to 4mg/l of Bunker-C oil, respectively. The ultimate oxygen demand of mixture was increased as a mix ratio of dispersant to Bunker-C oil changed from 1:10 to 10:5. This means that the more dispersants are applied to the sea for Bunker-C oil cleanup, the more decreases the dissolved oxygen level in the seawater.

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A Comparative Study on the Spatial Sense of Interior and Exterior Spaces (실내와 실외의 공간감 비교 연구)

  • Yoo, Mi-Kyoung;Im, Seung-Bin
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.5
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    • pp.63-72
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    • 2012
  • In contemporary times, "environmental designers" need to consider both exterior and interior aspects because of the growing trend in dissolution between exterior and interior spaces. To quantify "spatial sense" which serves as the standard for environmental design, this study has asked 63 subjects to evaluate 15 interior and 14 exterior spaces. The "spaciousness (small-large)", "openness(closed-open)", "warmness(warm-cold)", "brightness(bright-dark)", "softness(soft-hard)", "spatial intimacy" and "frequency of visit" were adopted as variables of spatial sense. Through the analysis of these variables, this study could gain the difference between spatial sense for exterior and interior environments, quantify the spatial sense that physically and psychologically appropriates to human beings. The result of this study can be summarized as follows: Twice the amount of spaciousness was observed between the interior and exterior spaces. And the standard on intimate space is established with W/H ratio of 5.71 and high Window/Wall Area ratio in the interior and an area of 3,800m2 and a W/H ratio of 5.57 in exterior. The difference between the spatial sense in the interior and exterior space is mostly dependent on the psychological sense. The increase of physical size caused by the interior space to be perceived as cold, dark and hard psychologically, but exterior space to be perceived as warm, bright and soft. Psychological senses, especially softness, affect spatial intimacy to the greatest extent among the given variables. As the psychological senses for interior spaces were largely independent from the given space's size and perceptive senses, the size of the interior space, which exhibited spatial intimacy, could not be deduced. In comparison to this, due to the high dependency between the psychological senses for exterior spaces and the given space's size and perceptive senses. The study also showed that interior and exterior spaces have relatively different spatial sense and physical standards. Such research results are predicted to provide applicable standards for environmental designers for exterior and interior spaces in the future.

The research for the yachting development of Korean Marina operation plans (요트 발전을 위한 한국형 마리나 운영방안에 관한 연구)

  • Jeong Jong-Seok;Hugh Ihl
    • Journal of Navigation and Port Research
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    • v.28 no.10 s.96
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    • pp.899-908
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    • 2004
  • The rise of income and introduction of 5 day a week working system give korean people opportunities to enjoy their leisure time. And many korean people have much interest in oceanic sports such as yachting and also oceanic leisure equipments. With the popularization and development of the equipments, the scope of oceanic activities has been expanding in Korea just as in the advanced oceanic countries. However, The current conditions for the sports in Korea are not advanced and even worse than underdeveloped countries. In order to develop the underdeveloped resources of Korean marina, we need to customize the marina models of advanced nations to serve the specific needs and circumstances of Korea As such we have carried out a comparative analysis of how Austrailia, Newzealand, Singapore, japan and Malaysia operate their marina, reaching the following conclusions. Firstly, in marina operations, in order to protect personal property rights and to preserve the environment, we must operate membership and non-membership, profit and non-profit schemes separately, yet without regulating the dress code entering or leaving the club house. Secondly, in order to accumulate greater value added, new sporting events should be hosted each year. There is also the need for an active use of volunteers, the generation of greater interest in yacht tourism, and the simplification of CIQ procedures for foreign yachts as well as the provision of language services. Thirdly, a permanent yacht school should be established, and classes should be taught by qualified instructors. Beginners, intermediary, and advanced learner classes should be managed separately with special emphasis on the dinghy yacht program for children. Fourthly, arrival and departure at the moorings must be regulated autonomically, and there must be systematic measures for the marina to be able, in part, to compensate for loss and damages to equipment, security and surveillance after usage fees have been paid for. Fifthly, marine safety personnel must be formed in accordance with Korea's current circumstances from civilian organizations in order to be used actively in benchmarking, rescue operations, and oceanic searches at times of disaster at sea.

Antithrombotic Activities of Cheongkookjang and Cheongkookjang Fermented with Green Tea or Mugwort (청국장 및 녹차, 쑥이 첨가된 청국장의 항혈전 활성)

  • Lee, Kyung-Ae;Jang, Jeong-Oak;Yoon, Hye-Kyung;Kim, Moo-Sung
    • Korean Journal of Microbiology
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    • v.43 no.4
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    • pp.298-303
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    • 2007
  • Antithrombotic activities of water extract of cheongkookjang and cheongkookjang fermented with green tea or mugwort were evaluated on some antithrombosis related activities in vitro and thrombotic death inhibition in vivo. Cheongkookjang made of white soybean (Glycine max) or black small soybean (Rhynchosia nulubilis) showed potent antioxidative activities. Addition of green tea or mugwort during cheongkookjang fermentation increased the antioxidative activity, cheongkookjang with green tea showed more drastic increase compared with cheongkookjang with mugwort. Nitrite scavenging effects of the cheongkookjang extracts were prominent but the addition of green tea or mugwort seldom increased the scavenging effects. All the cheongkookjang extracts showed strong inhibitory activities on platelet aggregation. The inhibitory activities of cheongkookjang were increased considerably by addition of green tea or mugwort even with low concentration. Plasmin unit as fibrinolytic activity was not affected considerably by addition of green tea. Addition of mugwort decreased the activity transiently at low concentration ($0.3{\sim}1.0%$) but increased again slowly at higher concentration ($1{\sim}3%$). In vitro thrombotic death inhibition test, the antithrombotic activity of cheongkookjang made of black small bean with green tea was higher by about 1.5 times compared to that without green tea. As results, cheongkookjang might inhibit antithrombosis not only by fibrinolytic action but also by inhibition of platelet aggregation and antioxidative action. The addition of functional materials such as green tea or mugwort could increase the antithrombotic function, even at low concentration.

What Do Scientists Think about the Nature of Science? - Exploring Views of the Nature of Science of Korean Scientists Related with Life Science Area (우리나라 생명과학 관련 분야 재미 과학자들은 어떻게 과학의 본성을 이해하고 있는가?)

  • Lee, Young Hee
    • Journal of The Korean Association For Science Education
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    • v.34 no.7
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    • pp.677-691
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    • 2014
  • Understanding of the nature of science (NOS) has been a consistent topic as one of the most important goals in science education for the past several decades. Even though there is a variety of research related with the NOS conducted in science education, few researches has been conducted for the conception of scientists regards to the nature of science (Bayir et al., 2014; Taylor et al., 2008; Wong & Hudson, 2008). Recently, researchers in science education turned their attention to identifying views of scientists about the nature of science since they recognized the importance of participation of scientists in science education (Southerland et al., 2003; Taylor et al., 2008). This study was conducted to examine the Korean scientists' views of the nature of science. Through the use of semi-structured questionnaire and in-depth interview the views of 35 scientists who belong to the Korean-American Scientists and Engineers Association (KSEA) regards to the nature of science were explored. Findings show that while the scientists have more informed views with respect to the tentativeness of scientific knowledge, cultural and social influence embedded in science, the limitation of science, and the collaboration of science with others, the scientists have more na${\ddot{i}}$ve views about the distinction between laws and theories, the existence of a universal scientific method, and the importance of imagination and creativity. As such, it can be assumed that the scientists cannot conceptualize their notion in a philosophical sense even though they are engaged in scientific work in reality (Bayir et al., 2014).

Protective Effects of New Herbal Composition (MH-30) against Radiation Injuries in Hematopoietic and Self-Renewal Tissues (생약조성물(MH-30)의 면역조혈계 및 재생조직 방사선 손상에 대한 방호 효과)

  • Jung, Uhee;Park, Hae-Ran;Lee, Ho-Yong;Baek, Ga-Young;Jo, Sung-Kee
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.7
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    • pp.948-957
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    • 2016
  • We previously developed an herbal composition (HemoHIM) based on the water extracts of Angelica gigas radix, Cnidium officinale rhizoma, and Paeonia japonica radix to protect and recover hematopoietic and intestinal tissues against radiation injuries. In this study, to develop a composition with improved activities based on enhanced fat-soluble polyphenol contents, we prepared a new herbal composition, MH-30, from the above three herbs by 30% ethanol extraction and hot water extraction. HPLC analysis of the ethanol fractions of MH-30 and HemoHIM revealed that MH-30 had higher contents of many fat-soluble polyphenol compounds than HemoHIM (8.7-fold increase for decursin), whereas contents of water-soluble polyphenol compounds showed little differences between the two compositions. Then, we evaluated MH-30 and HemoHIM for their in vitro antioxidant and immune cell-stimulating activities as well as in vivo protective effects against radiation injuries in hematopoietic and self-renewal tissues. In antioxidant activity assays, MH-30 showed higher hydroxyl radical scavenging activity than HemoHIM (1.4- to 1.9-fold for compositions and 2.3- to 4.5-fold for ethanol fractions). On the other hand, MH-30 and HemoHIM exhibited similar immune cell-stimulating activities as measured by in vitro lymphocyte proliferation. MH-30 increased endogenous spleen colony formation, decreased bone marrow cell apoptosis, and enhanced survival of intestinal crypts in irradiated mice, demonstrating effective protection of MH-30 against radiation-induced injuries in hematopoietic and self-renewal tissues. The 30-day survival rate of lethally irradiated mice, a comprehensive index for radioprotective efficacy, was also elevated by MH-30. Noticeably, MH-30 showed higher protective effects than HemoHIM in all mouse experiments. These results demonstrate that MH-30 can protect hematopoietic and self-renewal tissues against radiation injuries more effectively than HemoHIM. Therefore, MH-30 can be a good candidate to reduce radiation injuries in hematopoietic and self-renewal tissues incurred by radiation accidents or cancer radiation therapy.

Development of Embedded Board for Integrated Radiation Exposure Protection Fireman's Life-saving Alarm (일체형 방사선 피폭 방호 소방관 인명구조 경보기의 임베디드 보드 개발)

  • Lee, Young-Ji;Lee, Joo-Hyun;Lee, Seung-Ho
    • Journal of IKEEE
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    • v.23 no.4
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    • pp.1461-1464
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    • 2019
  • In this paper, we propose the development of embedded board for integrated radiation exposure protection fireman's life-saving alarm capable of location tracking and radiation measurement. The proposed techniques consist of signal processing unit, communication unit, power unit, main control unit. Signal processing units apply shielding design, noise reduction technology and electromagnetic wave subtraction technology. The communication unit is designed to communicate using the wifi method. In the main control unit, power consumption is reduced to a minimum, and a high performance system is formed through small, high density and low heat generation. The proposed techniques are equipment operated by exposure to poor conditions, such as disaster and fire sites, so they are designed and manufactured for external appearance considering waterproof and thermal endurance. The proposed techniques were tested by an authorized testing agency to determine the effectiveness of embedded board. The waterproof grade has achieved the IP67 rating, which can maintain stable performance even when flooded with water at the disaster site due to the nature of the fireman's equipment. The operating temperature was measured in the range of -10℃ to 50℃ to cope with a wide range of environmental changes at the disaster site. The battery life was measured to be available 144 hours after a single charge to cope with emergency disasters such as a collapse accident. The maximum communication distance, including the PCB, was measured to operate at 54.2 meters, a range wider than the existing 50 meters, at a straight line with the command-and-control vehicle in the event of a disaster. Therefore, the effectiveness of embedded board for embedded board for integrated radiation exposure protection fireman's life-saving alarm has been demonstrated.

The Effects of Question-Creation Training on Metacognition, Self-efficacy and Question Levels (문제생성훈련 수업이 중학생의 메타인지와 자기효능감 및 문제 수준에 미치는 영향)

  • Ryu, Soo-Jin;Kim, Yoon-Seok;Lee, Ji-Hwa;Moon, Seong-Bae
    • Journal of The Korean Association For Science Education
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    • v.31 no.2
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    • pp.225-238
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    • 2011
  • The purpose of this study was to investigate the effects of the instruction with question-creation training, compared with traditional science instructions. The instruction with question-creation training is to give students chances to make questions by themselves based on what they learned before the end of the classes. The four effects of the instruction were studied: students' achievement, metacognition, self-efficacy, and the level of the questions created by the students according to different proficiency levels. Research data was gathered from 65 second grade students at a middle school in Busan. The comparative group was instructed in traditional lecture-type teaching method. The experimental group was instructed with questioncreation training. Students in the experimental group were asked to make 3 questions by themselves and then, to solve their peers' questions about 15 minutes before the end of the classes. Both groups were divided into 3 groups by proficiency level according to the results of last semester's science test. Before the research, a metacognition test and a self-efficacy test were conducted. After the research, an achievement test, a question level test, a metacognition test, and a self-efficacy test were conducted and analyzed by t-test. The research data for question level was analyzed by one-way ANCOVA. The results of this study revealed that question-creation training has a positive effect on student's achievement, metacognition, and self-efficiency. It also showed most of the students have gained an ability to make higher-level questions regardless of their proficiency level due to the increased number of students who made higher-level questions. It also showed that most of the students could gain an ability to make higher-level questions regardless of their proficiency level from the fact that the number of students who made higher-level questions increased in every proficiency level.

Novel LTE based Channel Estimation Scheme for V2V Environment (LTE 기반 V2V 환경에서 새로운 채널 추정 기법)

  • Chu, Myeonghun;Moon, Sangmi;Kwon, Soonho;Lee, Jihye;Bae, Sara;Kim, Hanjong;Kim, Cheolsung;Kim, Daejin;Hwang, Intae
    • Journal of the Institute of Electronics and Information Engineers
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    • v.54 no.3
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    • pp.3-9
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    • 2017
  • Recently, in 3rd Generation Partnership Project(3GPP), there is a study of the Long Term Evolution(LTE) based vehicle communication which has been actively conducted to provide a transport efficiency, telematics and infortainment. Because the vehicle communication is closely related to the safety, it requires a reliable communication. Because vehicle speed is very fast, unlike the movement of the user, radio channel is rapidly changed and generate a number of problems such as transmission quality degradation. Therefore, we have to continuously updates the channel estimates. There are five types of conventional channel estimation scheme. Least Square(LS) is obtained by pilot symbol which is known to transmitter and receiver. Decision Directed Channel Estimation(DDCE) scheme uses the data signal for channel estimation. Constructed Data Pilot(CDP) scheme uses the correlation characteristic between adjacent two data symbols. Spectral Temporal Averaging(STA) scheme uses the frequency-time domain average of the channel. Smoothing scheme reduces the peak error value of data decision. In this paper, we propose the novel channel estimation scheme in LTE based Vehicle-to-Vehicle(V2V) environment. In our Hybrid Reliable Channel Estimation(HRCE) scheme, DDCE and Smoothing schemes are combined and finally the Linear Minimum Mean Square Error(LMMSE) scheme is applied to minimize the channel estimation error. Therefore it is possible to detect the reliable data. In simulation results, overall performance can be improved in terms of Normalized Mean Square Error(NMSE) and Bit Error Rate(BER).