• Title/Summary/Keyword: 연구 분석

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Combustion Characteristics of Cow Manure Pellet as a Solid Fuel Source (고체연료원으로서의 우분 펠릿 연소특성)

  • Jeong, Kwang-Hwa;Lee, Dong-jun;Lee, Dong-Hyun;Lee, Sung-Hyoun
    • Journal of the Korea Organic Resources Recycling Association
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    • v.27 no.2
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    • pp.31-40
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    • 2019
  • In Korea, 51,013 thousand tons of livestock manure was generated in 2018. A total of 46,530 thousand tons, which is 91.2% of the total amount of livestock manure generated, was treated by composting(40,647 thousand tons) or liquid fertilization(5,884 thousand tons) method. At present, the policy of livestock manure treatment in Korea is to make livestock manure into organic fertilizer(compost, liquid fertilizer) and then to applicate it on agricultural land. And this policy is very effective in terms of livestock manure treatment and nutrient recycling. However, considering the steadily declining farmland area for decades, the use of livestock manure compost could be limited in the future. There is also concern that local nutrient overloading, nutrient management regulation, and restrictions on the number of livestock may become serious problem for livestock manure treatment. In addition, there are some opinions that nutrient derived from livestock manure may flow into tributaries of major dams. In recent years, there has been a suspicion that fine dust may be generated from livestock manure compost. In recent years, the use of livestock manure fertilizer has been rapidly increasing, there is a growing demand of the development of new technologies for livestock manure treatment. Especially, cow excretes a larger amount of manure than other livestock, so that the efficiency of development of new technology for cow manure treatment will be high. Therefore, in this study, the combustion characteristics of cow manure pellet were investigated in order to analyzed whether cow manure could be used as source of solid fuel. During the combustion test, the weight loss of the cow manure pellet began to increase when the temperature of the combustion chamber reached $300^{\circ}C$. The ratio of $H_2$, $CH_4$, CO in the pyrolysis gas produced in the pyrolysis process of cow manure pellet were 6.65~11.62%, 0.58~1.54 and 11.47~14.07%, respectively.

Food purchase in e-commerce and its relation to food habit of adult women in Incheon and Gyeonggi (인천 및 경기지역 성인 여성의 전자상거래에서 식품 구매실태와 식습관과의 관련성)

  • Park, Yu-Jin;Kim, Mi-Hyun;Choi, Mi-Kyeong
    • Journal of Nutrition and Health
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    • v.52 no.3
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    • pp.310-322
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    • 2019
  • Purpose: This study examined the food purchases from e-commerce and its relation to eating behaviors or habits in adult women in Incheon and Gyeonggi. Methods: A total of 410 subjects participated in the questionnaire survey. Food purchases in e-commerce and food habits were compared according to age, marital status, and food purchase status in e-commerce of the subjects. Results: Approximately 88% of the subjects had experience of buying foods by e-commerce; more than 40% of the subjects spent less than 100,000 Won buying foods by e-commerce in the past 6 months. The major purchases were coffee and tea, instant food and frozen food, and water and beverages. The reasons for buying foods in e-commerce were cheaper price, convenience of delivery, and variety of food choices. The main factors considered for purchasing foods in e-commerce were price and quality followed by rapid and accurate delivery, and food label and information. Approximately 70% of the subjects were very satisfied or satisfied with their food purchase in e-commerce, and 96% answered that they were willing to buy food in e-commerce again. The perception on the advantages of food purchases in e-commerce was 3.6 points out of 5 and significantly lower in the over 50s and married group. The subjects with experience and high cost of food purchase in e-commerce showed significantly low scores of dietary behaviors and eating habits, which is undesirable. Conclusion: A high percentage of people purchased foods by e-commerce, and they showed undesirable eating habits, especially when the cost of purchasing foods by e-commerce is high. These results showed that purchasing foods in e-commerce may be related to consumers' food habits. Therefore, continuous attention and nutrition guidance for e-commerce consumers are needed.

Study on Improvement of Family Assistance System for Victim's Family of Air Traffic Accident (항공사고 피해자 가족지원 제도개선 연구)

  • Jeon, Jong-Jin;Kim, Hui-yang;Yoo, Kwang-Eui
    • The Korean Journal of Air & Space Law and Policy
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    • v.33 no.2
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    • pp.315-343
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    • 2018
  • In the event of an air accident, the media and members of the general public pay attention to the victim of the accident and are deeply concerned about their actions and rewards. However, through the accident of Air China(CCA) Flight 129, which occurred in 2002, we were able to confirm that it is a real problem that the victims of the air accident as well as the victims suffer much suffering and serious aftermath. Nevertheless, Korea's system for assistance the families of victims of air accident is very poor. On the other hand, when Trans-World Airlines(TWA) Flight 800 exploded and crashed over the Atlantic Ocean in 1996, the United States enacted a law to assistance the families of the victims of the accident. According to this law, systematic assistance and management of not only the victims of the accident but also their families, minimize the additional damage of victims and victims' families and help them to get rid of the accident after the accident. In particular, the measures taken by the US authorities in response to an accident in which an Asiana Airlines flight(AAR) 214 crashed during a landing at San Francisco International Airport in 2013, made a lot of suggestions for us to assistance the victims and their families in an air accident. The purpose of this paper is to suggest the necessity of improving the system for victims and victim's family assistance in air accident. In this paper, we analyze the domestic and foreign legal systems and related cases in past accidents, identify the deficiencies of the Korean system, and derive the necessity to improve the related system. It is also important to make sure that victims' families are relieved from early psychological and economic shocks and that the results of accident investigations are reliable. Relevant ministries, airlines, and related agencies should recognize that prompt and systematic assistance and cooperation is needed to ensure that victims and families are relieved of the impact and confidence in the investigation, as is the case in the United States. In addition, efforts should be made to supplement the related laws for the assistance of aircraft victims and victims' families, to establish manuals for implementation, to plan and to implement them promptly in the event of an accident. To achieve this, it is necessary to establish regulations for the legal institutionalization of the roles and responsibilities of national and state agencies on victims of aviation accidents and family assistance. And the victim and family assistance plan that the airline has to submit to it, as specified in the current law, need to specify that item. In addition, new and supplemented contents should be integrated into a single clause or proposed as a separate special law for the purpose of applying a clear law.

Physicochemical properties of dried Saururus chinensis and the antioxidative activities of water and 70% ethanol extracts (덖음온도를 달리하여 전저리한 삼백초 건조물의 이화학적 특성 및 물과 70% 에탄올 추출물의 항산화효과)

  • Kang, Myung-Hwa;An, Su-Mi;Kim, Do-Hee
    • Journal of Nutrition and Health
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    • v.52 no.4
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    • pp.399-407
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    • 2019
  • Purpose: This study was conducted to evaluate the physicochemical properties of different batches of Saururus chinensis using different roasting temperature that were dried at different using different roasting temperatures and their were determined the antioxidative activities of water and 70% ethanol extracts. Methods: Extracts were examined for the total phenolic acid content, the and flavonoids contents and the antioxidant properties, including DPPH radical scavenging activity, ABTs scavenging activity and, the reducing power. Results: Moisture content was significantly higher in the LSC and the crude ash content was significantly higher in the HSC. The crude protein content was higher in the LSC (although not significantly), and the crude fat and carbohydrate contents were higher in the HSC (although not significantly). The total phenolic content was lower in the samples extracted with water, but there was no significant difference. However, the extracts extracted with 70% ethanol at a high drying temperature were significantly higher. The low temperature and high drying temperature batches of Saururus chinensis were significantly higher in the samples extracted with 70% ethanol than those extracted with 70% ethanol. The total phenolic acid content, the total flavonoid content and the electron donating ability were highest in the ethanol extract of Saururuschinensis treated at a high temperature. However, the ABTs radical activity was highest in the water extracted, high-temperature treated Saururuschinensis. The 70% ethanol extract of high temperature roasted Saururuschinensis had the highest antioxidative activities of all the Saururuschinensis batches. Conclusion: The total phenolic acid contents, total flavonoid contents, electron donating activity and reducing power activity were highest in all the 70% ethanol extraction batches of the high-temperature treated samples.

Cytotoxicity of Particulate Matter in Various Human Cells Lines (미세먼지가 다양한 사람 세포주에 미치는 세포 독성)

  • Lee, Ji-Hyeon;Lee, Joo-Yeong;Kim, Mi-Jeong;Kim, Hyeon-Ji;Lee, Sung-Ho;Jeon, Byeong-Gyun
    • Journal of Life Science
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    • v.29 no.6
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    • pp.724-734
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    • 2019
  • The present study investigated the cytotoxicity of particulate matter (PM) derived from car air filter (outdoor PM) and home cleaner filter (indoor PM) in the various human cell lines. Each outdoor and indoor PM were harvested by ethanol extraction method, subsequently sieved with 10 um filter paper, sterilized with autoclave and added to culture media. The half maximal inhibitory concentration ($IC_{50}$) values was significantly (p<0.05) lower in the outdoor PM, compared with indoor PM, and the significantly (p<0.05) higher $IC_{50}$ values were observed in the cancer cell lines (A-549 lung adenocarcinoma and AGS stomach adenocarcinoma), than those of normal MRC-5 fibroblasts and dental papilla tissue derived-mesenchymal stem cells (DSC). After being exposed to $100{\mu}g/ml$ outdoor PM for 7 days, the population doubling time (PDT) was significantly (p<0.05) increased in especially MRC-5 and DSC cell lines, compared with untreated cell lines. Further, the expression of senescence-associated ${\beta}$-galactosidase activity was up-regulated in all the cells exposed to outdoor PM than those of untreated control. Besides, the expression level of inflammation-associated genes, such as cyclooxygenase-2 (COX-2) and interleukin-6 (IL-6) was found to be significantly (p<0.05) increased in the outdoor PM-treated cell lines than those of untreated cell lines. Our results showed that PM induces the cytotoxicity via arrest of cell growth, cell damage and inflammation response.

Antioxidant, Antimicrobial and Cellular Protective Effects of Lycopus lucidus Extract and Fraction (택란 추출물 및 분획물의 항산화, 항균 및 세포 보호 효과)

  • Lee, Jin Kyoung;Park, Young Min;Lee, Sang Lae;Song, Ba Reum;Lee, Yun Ju;Park, Soo Nam
    • Applied Chemistry for Engineering
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    • v.30 no.1
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    • pp.114-121
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    • 2019
  • In this study, antioxidative, antibacterial and cytoprotective effects of the ethanol extract and ethylacetate fraction of Lycopus lucidus (L. lucidus) were compared and analyzed. Free radical scavenging activities ($FSC_{50}$) of the L. lucidus extract and fraction were found to be 65.1 and $64.9{\mu}g/mL$ respectively. In the $Fe^{3+}-EDTA/H_2O_2$ system, the reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) for the extract and fraction were 6.6 and $6.3{\mu}g/mL$, respectively which showed excellent total antioxidant abilities. The extract showed antibacterial activity against S. aureus, while the fraction showed in all the bacteria except for A. niger. The cytoprotective effect of L. lucidus extract was compared to that of the fraction and the effect against $^1O_2$-induced cellular damage of human erythrocytes (${\tau}_{50}$) was 51.3 and 73.7 min at $50{\mu}g/mL$, respectively. For the cytoprotective effect of keratinocytes damaged by $H_2O_2$ and UVB, the extracts did not show any efficacy but showed efficacy at $1-2{\mu}g/mL$, respectively. The fraction increased the cell viability up to 85.8 and 81.9%, respectively. As a result of intracellular ROS scavenging activity, the scavenging activity was observed at $1-2{\mu}g/mL$ of the fraction. From the results comparing the physiological activities of L. lucidus extract and the fraction, the ethylacetate fraction of L. lucidus has antioxidative effect similar to that of the extract whereas superior antimicrobial and cytoprotective effects than that of the extract. Overall, the ethylacetate fraction of L. lucidus protects cells from an external stress which can be used as a potential cosmetic material.

Mytilin B, an Antimicrobial Peptide from the Hemocyte of the Hard-shelled Mussel, Mytilus coruscus : Isolation, Purification, and Characterization (참담치(Mytilus coruscus) 혈구(hemocyte) 유래 항균 펩타이드 mytilin B의 정제 및 특성 분석)

  • Lee, Min Jeong;Oh, Ryunkyoung;Kim, Young-Ok;Nam, Bo-Hye;Kong, Hee Jeong;Kim, Joo-Won;Park, Jung Youn;Seo, Jung-Kil;Kim, Dong-Gyun
    • Journal of Life Science
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    • v.28 no.11
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    • pp.1301-1315
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    • 2018
  • We purified an antimicrobial peptide from the acidified hemocyte extract of Mytilus coruscus by $C_{18}$ reversed-phase high-performance liquid chromatography (RP-HPLC). The peptide was 4041.866 Da based on matrix-assisted laser desorption ionization time-of-flight mass spectrophotometer (MALDI-TOF/MS) and the 25 amino acids of the N-terminus sequence were identified. Comparison of this sequence of the purified peptide with the N-terminus sequences of other antimicrobial peptides revealed 100% identity with the mytilin B precursor of Mytilus coruscus. We also identified a 312 bp open-reading frame (ORF) encoding 103 amino acids based on the obtained amino acid residues. The nucleotide sequence of this ORF and the amino acid sequence also revealed 100% identity with the mytilin B precursor of Mytilus coruscus. We synthesized two antimicrobial peptides with an alanine residue in the C-terminus, and designated them mytilin B1 and B2. These two antimicrobial peptides showed antimicrobial activity against gram-positive bacteria, including Bacillus cereus and Streptococcus parauberis (minimal effective concentration, MECs $41.6-89.7{\mu}g/ml$), gram-negative bacteria, including Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Providencia stuartii, Pseudomonas aeruginosa, and Vibrio ichthyoenteri (MECs $7.4-39.5{\mu}g/ml$), and the fungus Candida albicans (MECs $26.0-31.8{\mu}g/ml$). This antimicrobial activity was stable under heat and salt conditions. Furthermore, the peptides did not exhibit significant hemolytic activity or cytotoxic effects. These results suggest that mytilin B could be applied as alternative antibiotic agent, and they add to the understanding of the innate immunity of hard-shelled mussels.

Analysis of Transcriptional Activity and Estrogen Responsiveness of Regulatory Elements in Chicken Ovalbumin Promoter (닭 오브알부민 프로모터의 길이에 따른 유전자 발현 활성 및 에스트로겐 반응성 분석)

  • Yang, Hyeon;Kim, Kyung-Woon;Kim, Jeom Sun;Woo, Jae-Seok;Lee, Hwi-Cheul;Choi, Hoonsung;Jung, Sun Keun;Sureshkumar, Shanmugam;Lee, Haesun;Oh, Keon Bong;Byun, Sung June
    • Korean Journal of Poultry Science
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    • v.46 no.1
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    • pp.17-24
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    • 2019
  • Chickens have been considered as well-defined animal bioreactor. The optimized ovalbumin promoter is essential for recombinant protein production in transgenic chicken. Here we try to compare the activity and identify the effect of estrogen on ovalbumin promoter according to each promoter length with estrogen response element (ERE) existence. We cloned two (2.8 and 5.5 kb) ovalbumin promoters that the 5.5 kb contained the ERE but the 2.8 kb did not, and these two promoters were cloned to pGL4.11 vector. Additionally, we constructed another pGL4.11 vector containing of the 4.4 kb (with ERE) ovalbumin promoter deleted with 1 kb between ERE region and the 2.8 kb promoter. For reporter assay, HeLa, MES-SA, LMH/2A, and cEF cells were transfected with all the pGL4.11 vectors. The comparative analysis showed that the mutated 4.4 kb promoter has more potent activity than the 2.8 and 5.5 kb promoters in HeLa, MES-SA, and LMH/2A cells. However, there is no significant difference in cEFs. Also, these cells transfected with the mutated 4.4 kb promoter were treated with the $17{\beta}$-estradiol (0~3,000 nM) and HeLa, MES-SA, and LMH/2A cells showed estrogen responsibilities, but cEFs did not. Besides, the mutated 4.4 kb promoter has still higher activity than the 2.8 and 5.5 kb promoter, and there is no transcriptional induction effect in 2.8 kb promoter at 500 nM estrogen that is blood concentration of laying hens. Hence our study strongly suggested that the mutated 4.4 kb promoter is considered as one of the most efficient length for generating transgenic chicken.

Stress distribution of molars restored with minimal invasive and conventional technique: a 3-D finite element analysis (최소 침습적 충진 및 통상적 인레이 법으로 수복한 대구치의 응력 분포: 3-D 유한 요소 해석)

  • Yang, Sunmi;Kim, Seon-mi;Choi, Namki;Kim, Jae-hwan;Yang, Sung-Pyo;Yang, Hongso
    • Journal of Dental Rehabilitation and Applied Science
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    • v.34 no.4
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    • pp.297-305
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    • 2018
  • Purpose: This study aimed to analyze stress distribution and maximum von Mises stress generated in intracoronal restorations and in tooth structures of mandibular molars with various types of cavity designs and materials. Materials and Methods: Three-dimensional solid models of mandible molar such as O inlay cavity with composite and gold (OR-C, OG-C), MO inlay cavity with composite and gold (MR-C, MG-C), and minimal invasive cavity on occlusal and proximal surfaces (OR-M, MR-M) were designed. To simulate masticatory force, static axial load with total force of 200 N was applied on the tooth at 10 occlusal contact points. A finite element analysis was performed to predict stress distribution generated by occlusal loading. Results: Restorations with minimal cavity design generated significantly lower values of von Mises stress (OR-M model: 26.8 MPa; MR-M model: 72.7 MPa) compared to those with conventional cavity design (341.9 MPa to 397.2 MPa). In tooth structure, magnitudes of maximum von Mises stresses were similar among models with conventional design (372.8 - 412.9 MPa) and models with minimal cavity design (361.1 - 384.4 MPa). Conclusion: Minimal invasive models generated smaller maximum von Mises stresses within restorations. Within the enamel, similar maximum von Mises stresses were observed for models with minimal cavity design and those with conventional design.

Functional Properties of Muskmelon Vinegars Manufactured with Traditional Fermentation Methods (전통적인 발효 방법으로 제조된 참외식초의 기능적 특성)

  • Jung, Kyung Im;Ha, Na Yeon;Choi, Young Ju
    • Journal of Life Science
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    • v.29 no.3
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    • pp.345-353
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    • 2019
  • This study investigated the physiochemical properties, the anti-oxidant and alcohol metabolism enzyme activities, and the anti-inflammatory effects of three muskmelon vinegars prepared under different fermentation conditions, namely MV-1, MV-2, and MV-3. The total acidity of each vinegar was 4.00%, 4.32%, and 4.35%, respectively. Organic acid analysis showed that malic acid (58.37 mg/ml) was the most prevalent in MV-1 and that acetic acid was most prevalent in both MV-2 (46.95 mg/ml) and MV-3 (66.70 mg/ml). The total phenolic content of the muskmelon vinegars was highest at $129.74{\mu}g$ tannic acid equivalents (TAE)/ml in MV-3. The DPPH radical scavenging activity of the vinegars increased in a dose-dependent manner (p<0.05) and was 89.28% at MV-3 40% concentration. Similarly, SOD activitity increased in a concentration-dependent manner (p<0.05) so that levels for MV-1, MV-2, and MV-3 at 60% concentrations were 40.84%, 52.17% and 72.55%, respectively (p<0.05). Moreover, the ADH and ALDH activities of muskmelon vinegar were seen to increase in a concentration-dependent manner; ADH activity at 60% concentration was highest at 136.58% in MV-1 and ALDH activity at 60% concentration was highest at 100.25% in MV-2. The nitrite scavenging activities of MV-1, MV-2, and MV-3 at pH 1.2 were found to be 81.58%, 94.72%, and 87.75%, respectively. Anti-inflammatory effects were also examined, using LPS-stimulated RAW 264.7 cells, and nitric oxide production was reduced to 25.93%, 10.01%, and 79.75% by addition of MV-1, MV-2, and MV-3 at 1% concentration, respectively (p<0.05). These results suggest that the MV-3 muskmelon vinegar has great potential as an ingredient for high quality functional health beverages.