• Title/Summary/Keyword: Natural Science and Engineering

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Silver Contamination in Drinking Water of Gyeongbuk Area in Korea (경북 지역 먹는 물의 은 검출 특성)

  • Lee, Hea Geun;Kim, Jeong Jin;Kim, Young Hun
    • Korean Journal of Mineralogy and Petrology
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    • v.33 no.3
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    • pp.233-242
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    • 2020
  • As studies and developments of nano-material increase, the release of the nano-sized material to water environment increase. Especially, silver nanoparticles have been found as dissolved and particulate state since nano-silver particle have been intensively used in industrial and our living environment due to the anti-bacterial effect of the nano-particles. The silver nano-particles and silver ion gives adverse effect on ecology and US-EPA set a secondary drinking water standards as 0.1 mg/L. Current study focused on the analysis of silver in groundwater, small scale water supply systems in Gyeongbook area. The results have been compared with the secondary drinking water standards and discussed at the point of characteristics of the local area and purpose of use of the water sample. Among the total of 298 samples, 2 samples exceed the secondary drinking water standards of EPA, 0.64% rate. Community drinking water and simplified water service showed relatively high detection rate and groundwater gave relatively higher concentration of silver indicating anthropogenic source and natural source could contribute simultaneously on groundwater.

Expression of Recombinant Hybrid Peptide Gaegurin4 and LL37 using Fusion Protein in E. coli (Glutathione S-Transferase에 융합한 재조합 Hybrid Peptide Gaegurin-LL37의 대장균에서의 발현)

  • Bayarbat, Ishvaanjil;Lee, Jae-Hag;Lee, Soon-Youl
    • Microbiology and Biotechnology Letters
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    • v.40 no.2
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    • pp.92-97
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    • 2012
  • Antimicrobial peptides (AMPs) are important components of living organisms acting against Gram-negative and Gram-positive bacterial and fungal pathogens. Cathelicidin human peptides have a variety of biological activities that can be used in clinical applications. AMPs are not produced naturally in large quantities, and chemical synthesis is also economically impractical, especially for long peptides. Therefore, as an alternative, heterologous expression of AMPs by recombinant techniques has been studied as a means to reduce production costs. E. coli is an excellent host for the expression of AMPs, as well as other recombinant proteins, because of the low cost involved and its easy manipulation. However, overexpression of AMPs in E. coli has been shown to cause difficulties resulting from the toxicity of the subsequently produced AMPs. Therefore, fusion expression was theorized to be a solution to this problem. In this study, AMPs were expressed as fused proteins with the glutathione S-transferase (GST) binding protein to protect against the toxicity of AMPs when expressed in E. coli. The LL37, and hybrid gaegurin and LL37 (GGN4(1-16)-LL37(17-32), which we designated as GL32, peptides were expressed as GST-fusion proteins in E. coli and the fusion proteins were then purified by affinity columns. The purified peptides were obtained by removal of GST and were confirmed by western blot analysis. The purified antimicrobial peptides then demonstrated antimicrobial activities against Gram-negative and Gram-positive bacterial strains.

Upper Bounds for the Performance of Turbo-Like Codes and Low Density Parity Check Codes

  • Chung, Kyu-Hyuk;Heo, Jun
    • Journal of Communications and Networks
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    • v.10 no.1
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    • pp.5-9
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    • 2008
  • Researchers have investigated many upper bound techniques applicable to error probabilities on the maximum likelihood (ML) decoding performance of turbo-like codes and low density parity check (LDPC) codes in recent years for a long codeword block size. This is because it is trivial for a short codeword block size. Previous research efforts, such as the simple bound technique [20] recently proposed, developed upper bounds for LDPC codes and turbo-like codes using ensemble codes or the uniformly interleaved assumption. This assumption bounds the performance averaged over all ensemble codes or all interleavers. Another previous research effort [21] obtained the upper bound of turbo-like code with a particular interleaver using a truncated union bound which requires information of the minimum Hamming distance and the number of codewords with the minimum Hamming distance. However, it gives the reliable bound only in the region of the error floor where the minimum Hamming distance is dominant, i.e., in the region of high signal-to-noise ratios. Therefore, currently an upper bound on ML decoding performance for turbo-like code with a particular interleaver and LDPC code with a particular parity check matrix cannot be calculated because of heavy complexity so that only average bounds for ensemble codes can be obtained using a uniform interleaver assumption. In this paper, we propose a new bound technique on ML decoding performance for turbo-like code with a particular interleaver and LDPC code with a particular parity check matrix using ML estimated weight distributions and we also show that the practical iterative decoding performance is approximately suboptimal in ML sense because the simulation performance of iterative decoding is worse than the proposed upper bound and no wonder, even worse than ML decoding performance. In order to show this point, we compare the simulation results with the proposed upper bound and previous bounds. The proposed bound technique is based on the simple bound with an approximate weight distribution including several exact smallest distance terms, not with the ensemble distribution or the uniform interleaver assumption. This technique also shows a tighter upper bound than any other previous bound techniques for turbo-like code with a particular interleaver and LDPC code with a particular parity check matrix.

The Effects of Anti-Thrombotic Activities and Cardiovascular Improvement of Fermented Garlic Extracts (발효마늘 추출물의 항혈전 및 심혈관개선 효과)

  • Kim, Hyun Kyoung
    • The Journal of the Convergence on Culture Technology
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    • v.6 no.2
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    • pp.567-572
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    • 2020
  • The purpose of this study was to investigate the effects of Anti-Thrombotic Activities and Cardiovascular Improvement of Fermented Garlic Extracts. The incidence of cardiovascular diseases (CVDs) is increasing rapidly in developed countries, with CVDs now representing the leading cause of morbidity and mortality. Natural products and ethnomedicines have been shown to reduce the risk of CVDs. Garlic is a medicinal plant used throughout the world for its anti-inflammatory, antioxidant, and antiplatelet activities. We hypothesized that fermented preparations of these products may possess stronger antiplatelet effects than the non-fermented forms owing to the increased bioavailability of the bioactive compounds produced during fermentation. Therefore, we compared these compounds via in vitro and ex vivo platelet aggregation assays by using standard light transmission aggregometry and ex vivo granule secretions from rat platelets. We found that fermented preparations exerted more potent and significant inhibition of platelet aggregation both in vitro and ex vivo. Likewise, ATP release from dense granules of platelets was also significantly inhibited in fermented preparation-treated rat platelets compared to that in non-fermented preparation-treated ones. We concluded that fermented preparations exerted more potent effects on platelet function both in vitro and ex vivo, possibly as a result of the increased bioavailability of active compounds produced during fermentation. We therefore suggest that fermented products may be potent therapeutics against platelet-related CVDs and can be used as antiplatelet and antithrombotic agents.

Composting and Fertilizing Characteristics of Poultry Manure Mixture with Compressed Expansion Rice Hull as Bulking Agent (수분조절제로서 팽화왕겨를 이용한 계분 발효 특성 및 시비 효과)

  • Kim, Young-Sun;Cho, Sung-Hyun;Lee, Hoon-Soo;Lee, Geung-Joo
    • Journal of the Korea Organic Resources Recycling Association
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    • v.28 no.4
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    • pp.5-13
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    • 2020
  • This study was conducted to evaluate effects of compressed expansion rice hull (CERH) as bulking agent on physicochemical properties of composting poultry manure (PM) and of its fertilization on lettuce and pak choi growth. Treatments were designed as follows; sawdust treatment (90% PM + 10% sawdust; SP), peatmoss treatment (90% PM + 10% peatmoss; PP), and CERH treatments [PCR1 (90% PM + 10% CERH 1.3 mm) and PCR2 (90% PM + 10% CERH 3.0 mm)]. Physicochemical properties such as temperature, water content, pH, and total carbon of composted poultry piles for 31 days were unaffected by various bulking agents. However, total nitrogen content in compost pile was higher in PP and PCR1 than that of SP or PCR2. After composting for 31 days, content ranges of N, P2O5, and K2O in the composting PM piles were 19.1~19.7%, 47.6~51.6%, 2.76~3.65%, and 2.53~2.90%, respectively. As compared to SP treatment, dry weight of lettuce treated with PP and PCR1 increased by more than 10%, but only in PP for pak choi. These results indicated that CERH 1.3 could be used as bulking agents for composting PM on behalf of peatmoss or sawdust.

Antioxidant activity of partially characterized polysaccharides from the edible mushroom Pleurotus djamor var. roseus

  • Raman, Jegadeesh;Sivakumar, Archana;Lakshmanan, Hariprasath;Raaman, Nanjian;Shin, Hyun-Jae
    • Journal of Mushroom
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    • v.19 no.3
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    • pp.140-149
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    • 2021
  • Mushroom-derived polysaccharides, which are the primary bioactive constituents, are beneficial for human health. Polysaccharides have immuno-modulation, antitumor, and antioxidant properties. Additionally, they have antiviral properties and protect against chronic radiation stress. In this study, high yield water-soluble polysaccharides were obtained from Pleurotus djamor var. roseus basidiocarps. The crude polysaccharide (CP) was extracted sequentially by hot water and ethanol precipitation. The yield of the brown CPs was 5.6% dw. Diethylaminoethyl cellulose and Sepharose-6B column chromatography of CPs generated several fractions. Total glucan content was determined in all the fractions. The F1 fraction displayed the highest sugar content and was considered as a purified polysaccharide (PP). The total glucan and β-glucan content in the four fractions ranged between 76.85-2.95% and 75.08-1.46%, respectively. The yield of the PPs was 300 mg, and it was obtained as a white powder. The PPs were characterized by Fourier-transform infrared spectroscopy (FTIR) and thin-layer chromatography. The FTIR spectral details confirmed the presence of a xylopentose polysaccharide. The antioxidant activity of the PPs was evaluated using in vitro 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging assay and superoxide radical scavenging assay. The PPs showed strong DPPH free radical and superoxide anion radical scavenging activities in a dose-dependent manner. Purified PPs free of phenolics, protein, and carbohydrates were mainly responsible for the radical scavenging activity. The data suggest the potential of PPs as natural antioxidants.

Growth Properties of Mixtures with Mixed Organic Fertilizer and Dried Food Waste Powder in Pakchoi (Brassica rapa L.) (음식물류폐기물건조분말과 혼합유기질비료 혼합물의 청경채 생장 효과)

  • Kim, Young-Sun;Cho, Sung-Hyun;Lee, Hoonsoo;Lee, Geung-Joo
    • Journal of the Korea Organic Resources Recycling Association
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    • v.29 no.3
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    • pp.17-25
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    • 2021
  • This study was conducted to investigate effects of mixture with dried food waste powder (FWP) and mixed organic fertilizer (MOF) on growth of pakchoi. As compared with non-fertilizer treatment (NF) or control (MOF treatment), growth of pakchoi in FWP treatments (2,500 kg/ha, 5,000 kg/ha, 10,000 kg/ha) was inhibited by salt (NaCl) content in the FWP. In comparison with control, mixtures of MOF and FWP (FWP10, FWP20, and FWP30 treatment) were not significantly different, and their salt content correlated with pakchoi growth factors negatively (P<0.05). Applied of FWP10, (FWP10: 2,500 kg/ha, 2FWP10: 5,000 kg/ha, 3FWP10: 7,500 kg/ha, 4FWP10: 10,000 kg/ha), growth factors of FWP10, 2FWP10 and 3FWP10 treatment were not significantly different than those of chemical fertilizer treatment, and of 4FWP10 decreased. Correlation coefficient between NaCl supply by FWP10 application and growth factor was negative (P<0.01). These results indicated that FWP was used as another source of organic fertilizer, and the organic fertilizers blending with FWP inhibited a pakchoi growth by increase of salt content containing in the them or of salt supplying amount after their application.

Analysis of spatial interpretation and cultural valorization of groundwater resource using open data (공공데이터를 활용한 지하수자원의 공간적 해석과 문화적 가치부여에 대한 제안)

  • Han-Na, CHOI;Yong-Cheol, KIM;Jeong-Hyun, YU;Ye-Yeong, LEE;So-Jung, IN;Jong-Gyu, HAN
    • Journal of the Korean Association of Geographic Information Studies
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    • v.25 no.4
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    • pp.81-93
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    • 2022
  • There are many natural hot springs and mineral springs as well as the cultural heritage of the three kingdoms period in the Geum River basin including Chungcheong region. No specific regeneration and publicity plans for deteriorated facilities in this area has been presented. This study aims to suggest promising hot spots and complex water culture belt in the Chungcheong region and Geum River basin through the spatial interpretation of resources. The northern part of the Geum River basin is expected to become a therapeutic spring belt with many hot springs and CO2-rich springs. In the central and southern parts of the Geum River basin, it is considered that it will be possible to promote convergence publicity by using groundwater resources and cultural assets.

Research for Reduction of Body Fat and Development of High Functionality in Young Persimmon Fruit (체지방 감소 고기능성 발현 떫은 감 소재 개발 연구)

  • Kim, Soo Hyun;Lee, Ah Reum;Kim, Kyeong Jo;Kim, Il Gyu;Rhee, Man Hee;Kim, Hyun-Kyoung;Roh, Seong-Soo
    • The Korea Journal of Herbology
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    • v.33 no.2
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    • pp.1-7
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    • 2018
  • Objectives : This study was conducted to evaluate the antioxidant activity and inhibitory activity of pancreatic lipase in vitro using natural products sangju dungsi, chungdo bansi, kabju baekmok three kind of young persimmon fruit extracts and to develop a high - functional anti - obesity substance with reduced body fat. Methods : The antioxidative effect of the three kind of young persimmon fruit extracts was determined by hot water extraction, 30% EtOH extraction and 70% EtOH extraction. The antioxidant activities were evaluated through radical scavenging assays using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals. Furthermore, we examined total phenol and flavonoids contents. And the pancreatic lipase inhibition was measured by selecting the sangju dungsi extract with antioxidant effect. Results : The yield of water, 30% and 70% EtOH extract from young persimmon fruit was sangju dungsi (water 8.3%, 30% EtOH 18.1%, 70% EtOH 16.9%), chungdo bansi (water 16.2%, 30% EtOH 16.1%, 70% EtOH 11.6%), kabju baekmok (water 16%, 30% EtOH 16.8%, 70% EtOH 11.5%). The sangju dungsi 30% EtOH extract eminent DPPH ($IC_{50}$, $19.25{\pm}2.94{\mu}g/m{\ell}$) and ABTS ($IC_{50}$, $19.94{\pm}4.07{\mu}g/m{\ell}$) radical scavenging activity, and total phenol $52.37{\pm}0.78mg/g$ and flavonoid $7.97{\pm}0.13mg/g$ contents were also excellent. It also showed excellent pancreatic lipase inhibition efficacy. Conclusion : The extracts from the three kind of young persimmon fruit extracts showed excellent antioxidant activity. sangju dungsi 30% EtOH extract may be a new anti-obesity material by reducing fat absorption through the inhibition of pancreatic lipase.

The evaluation of affected visual landscape of Taereung National Training Center to Taereung and Gangneung UNESCO World Heritage (세계문화유산 태릉·강릉에 대한 태릉선수촌의 시각적 경관영향률 분석)

  • Park, Jae-Min;Hong, Youn-Soon
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.33 no.4
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    • pp.65-76
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    • 2015
  • The purpose of this study is to determine the evaluation of affected visual landscape of Taereung National Training Center to Taereung and Gangneung UNESCO World heritages, South Korea. For this research, it used to offer the affected visual landscape rate and 3D simulation with Sketch up 8.0. This study conducted over 4 steps. Step 1, view points are selected with literature review and interview. Step 2, with Sketch up created 3D modelling and calculated the affected rate on the landscape. Step 3 individual buildings were mapped with the affected rate. Lastly, step 4 were identified the results through field research. From this results, the visual landscape of Taereung and Gangneung that are damaged by the Taereung National Training Center did not appear higher than initially expected. The entrance area on Gangneung, however, where is affected from Oryungwan, Korea Sports Institute, Philseung Gym needs to establish a way to improve that landscape impact. In case of Taereung, it did not appear damaged due to the hiding effect of the forest. By field survey to confirm those results, it shows seasonal differences. In the case of the summer and autumn derive similar results with 3D simulation but were exposed buildings in the winter and spring. It means when the simulation based on the summer and fall operates, it may not reflect the affected landscape of certain times such as winter and spring. This study has significance as a basic research to co-exist between the traditional heritage and modern heritage.