• Title/Summary/Keyword: sp.

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Molecular Phylogeny of Chattonella (Raphidophyceae) Species from Deungnyang Bay, Korea Using Single-Cell PCR (Single-cell PCR을 이용하여 분석한 득량만 Chattonella 종 (Raphidophyceae)의 분자계통학적 특성)

  • Kim, Jin Joo;Song, Seon Yeung;Park, Tae Gyu
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.7
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    • pp.967-972
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    • 2018
  • The genus Chattonella belonging to the class raphidophyceae, is a harmful algal bloom species. Recently, its occurrence has been increasing and expanding along the Korean coast. Species identification of the genus Chattonella only by morphological observation is difficult due to the lack of rigid cell walls. In this study, the morphological characteristics and genetic affinity of Chattonella sp. isolated from Deungnyang Bay in 2017 were examined. We carried out single-cell isolation from field samples then sequenced three different areas using the single-cell PCR method: 1) parts of ribosomal operon, the large subunit (LSU) of the rDNA, 2) the chloroplast-encoded subunit psaA of Photosystem I, and 3) rbcL encoding the large subunit of the Rubisco gene. The cells were morphologically very similar to the general genus Chattonella ($74.0{\pm}10.1{\mu}m$ in length, $33.1{\pm}3.6{\mu}m$ in width). The three partial gene sequences were insufficient to justify distinction at the species rank. However, they clustered at 99-100 % sequence similarity with C. marina, C. marina var. antiqua and C. marina var. ovata.

Repression of CCSP Expression by KLF4 (KLF4에 의한 CCSP 발현 억제)

  • Kwak, Inseok
    • Journal of Life Science
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    • v.28 no.12
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    • pp.1432-1437
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    • 2018
  • Clara cell secretory protein (CCSP) plays an important role in protecting the lungs from inflammation. This research focuses on identifying the cis-element for binding the repressor of CCSP gene expression. A DNase I footprinting experiment revealed three protected regions between -812 and -768 bp (45 bp) of the mCCSP promoter. One motif (D3: GCCTGGGAA) was 100% conserved across rat, hamster, and human. The addition of excess amounts of the D3 motif exhibited high competition within that 45 bp range in an electrophoretic mobility shift assay. However, when mutated D3 ($G{\underline{AA}}TG{\underline{TT}}AA$) was used, the competition was significantly reduced. This demonstrates that the D3 motif within that 45 bp region of the mCCSP promoter is an important site for the protein-DNA interaction. Transient transfection assays with -756 Luc resulted in highly decreased expression of CCSP than those with -812 Luc, suggesting that the 45 bp could function as a binding site for the repressor. Co-transfection of KLF4 exhibited significant repression of the -812 Luc but not the -768 Luc which clearly shows that KLF4 might function as a repressor for the CCSP gene and also suggests that the D3 motif is strongly involved in the binding of KLF4. In addition, when anti-KLF4 antibody was added, super-shifted bands were observed. This result demonstrates that KLF4 could function as a repressor by binding to this 45 bp region of the CCSP promoter and that the D3 motif might be involved in the specific binding of KLF4.

Bitcoin(Gold)'s Hedge·Safe-Haven·Equity·Taxation (비트코인(금)의 헷지·안전처·공평성·세제 소고)

  • Hwang, Y.
    • The Journal of Society for e-Business Studies
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    • v.23 no.3
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    • pp.13-32
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    • 2018
  • Btcoin has made a big progress through anonymity, decentralized authority, sharing economy, multi-ledger book-keeping, block-technology and the convenient financial vehicle. Bitcoin has the characteristics of mining and supply by decentralized suppliers, limited supply quantity and the partial money-like function as well as gold. The paper studies the hedge and safe-haven of Bitcoin and gold on daily frequency data over the period of July 20, 2010-Dec. 27, 2017 employing Asymmetric Vector GARCH. It finds that gold has the hedge and safe-haven against inflation and capital markets while Bitcoin has the weak hedge and the weak safe-haven. It shows insignificant effects of inflations of US and Korea on the volatilities of Bitcoin and gold. It also suggests the necessity of clearing of vagueness behind the anonymity for fair and transparent trade through the law application in the absence or fault in law (Lucken im Recht). following the spirit of the living constitution (lebendige gutes Recht oder Vorschrift). The relevant institutions are hoped to be given some of obligations such as registration, minimum required capital. report, disclosure, explanation, compliance and governance with autonomous corresponding rights. The study also suggests the reestablishment of the relevant financial law and taxation law. The hedge would not be successfully accomplished without the vigilant cautions of investors.

U-phosphate biomineralization induced by Bacillus sp. dw-2 in the presence of organic acids

  • Tu, Hong;Yuan, Guoyuan;Zhao, Changsong;Liu, Jun;Li, Feize;Yang, Jijun;Liao, Jiali;Yang, Yuanyou;Liu, Ning
    • Nuclear Engineering and Technology
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    • v.51 no.5
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    • pp.1322-1332
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    • 2019
  • In this paper, we systematically investigated the influence of some selected ligands on the U-phosphate precipitation induced by soil bacteria. These organics are widely ranging from acetate, lactate, salicylate and citrate to oxalate. The results revealed that uranium could be biomineralized on bacteria as $UO_2HPO_4{\cdot}4H_2O$ or $(UO_2)_3(PO_4)_2{\cdot}4H_2O$. The influence of organic ligands on the biomineralization had clear-cut correlations with its complexation abilities to uranyl. It was clearly found that the U-phosphate biomineralization was affected noticeably by the strong ligands (oxalate and citrate). Further study discovered that when the organic ligands were uncompetitive with biotic $PO_4^{3-}$ for uranyl, the transformation of uranyl species from ${\beta}-UO_2(OH)_2$ colloidal particles to free $UO_2^{2+}$-ligands ions could facilitate the U-phosphate biomineralization. However, when the organic ligands competed with biotic $PO_4^{3-}$ for uranyl, the U-phosphate biomineralization were inhibited. Our results highlight the importance of complex interactions of strong organic ligands with uranyl during the bacterial precipitation of U-P compounds and thus for the mobilization and immobilization of radio-nuclides in the nature.

Morphological Development of Egg and Larvae of Gnathopogon strigatus (Gobioninae) (줄몰개(Gnathopogon strigatus)의 난 발생 및 자치어 형태 발달)

  • Kim, Kyeong-Mu;Jeon, Hyoung-Joo;Song, Ha-Yun
    • Korean Journal of Ichthyology
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    • v.31 no.3
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    • pp.131-140
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    • 2019
  • This study is to observe species identification and early life history of Gnathopogon strigatus and to use it as a basis for taxonomic studies and conservation of species. For the experiments, the mature adults were collected at the Wang-suk Stream located in Namyang-ju city, Gyeong-gi Province and eggs were artificially fertilized by the wet method in the laboratory. The shape of the fertilized egg was globular, adhesive, opaque white in color and had no oil globules. The fertilized egg was 1.66~1.88 mm (average 1.76 mm, n=30) in diameter. The blastular stage occurred at 3 hours 05 minutes after fertilization and the gastrular stage was detected at 8 hours 30 minutes after fertilization. The embryo began to hatch about 54 hrs after fertilization under water temperature of $23{\pm}1^{\circ}C$ and the newly hatched larva (yolksac larva) were 4.1~4.7 mm (mean 4.4 mm, n=20) in total length (TL). The fourth day after hatching, the postlarva were 5.4~5.9 mm (mean 5.6 mm, n=20) in total length, their york sacs were completely absorbed and Start eating Artemia sp. Ten days after hatching, flexion larva were begins Notochord flexion were 7.5~8.6 mm (mean 8.1 mm, n=20) in total length. Sixteenth day after hatching, postflexion larva were complete Notochord flexion were 8.2~9.7 mm (mean 9.1 mm, n=20) in total length. At thirty-eight days after hatching, Juvenile were arrive integer all fin rays and similar to those of adults were 11.3~15.5 mm (mean 13.3 mm, n=20) in total length.

Increased Antioxidative Activity of Fermented Ligusticum striatum Makino Ethanol Extract by Bioconversion using Lactobacillus plantarum BHN-LAB 129 (Lactobacillus plantarum BHN-LAB 129의 생물전환공정을 통한 천궁 발효 추출물의 항산화 활성 증대)

  • Kim, Byung-Hyuk;Jeong, Su Jin;Jang, Jong-Ok;Lee, Jun-Hyeong;Park, YeEun;Kim, Jung-Gyu;Kwon, Gi-Seok;Hwang, Hak-Soo;Lee, Jung-Bok
    • Journal of Life Science
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    • v.29 no.8
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    • pp.846-853
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    • 2019
  • Phytochemical compounds of Ligusticum striatum Makino are used as traditional medicinal herbs in Asia. These compounds are reported to have pain relief and antioxidant activities in gynecological and brain diseases. In this study, we investigated the antioxidant effects of Ligusticum fermented ethanol extract from Lactobacillus plantarum BHN-LAB 129 isolated from Kimchi, a Korean traditional food. The total polyphenol and total flavonoid contents increased by about 116.2% and 281.0% respectively, in the fermented Ligusticum extract as compared with those in the nonfermented Ligusticum ethanol extract. Superoxide dismutase-like (SOD), DPPH radical scavenging, ABTS radical scavenging, and reducing power activities increased by around 139.9%, 199.6%, 301.0%, and 137.1%, respectively, in the fermented Ligusticum ethanol extract as compared with these parameters in the nonfermented Ligusticum ethanol extract, respectively. In conclusion, the fermented Ligusticum ethanol extract with L. plantarum BHN-LAB 129 was effective in increasing the antioxidant effects. The bioconversion process in this study points to the potential of using Ligusticum to produce phytochemical-enriched natural antioxidant agents with high added value. The findings may prove useful in the development of improved foods and cosmetic materials.

Regional Analysis of Extreme Values by Particulate Matter(PM2.5) Concentration in Seoul, Korea (서울시 초미세먼지(PM2.5) 지역별 극단치 분석)

  • Oh, Jang Wook;Lim, Tae Jin
    • Journal of Korean Society for Quality Management
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    • v.47 no.1
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    • pp.47-57
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    • 2019
  • Purpose: This paper aims to investigate the concentration of fine particulate matter (PM2.5) in the Seoul area by predicting unhealthy days due to PM2.5 and comparing the regional differences. Methods: The extreme value theory is adopted to model and compare the PM2.5 concentration in each region, and each best model is selected through the goodness of fitness test. The maximum likelihood estimation technique is applied to estimate the parameters of each distribution, and the fitness of each model is measured by the mean absolute deviation. The selected model is used to estimate the number of unhealthy days (above $75{\mu}g/m^3$ PM2.5 concentrations) in each region, with which the actual number of unhealthy days are compared. In addition, the level of PM2.5 concentration in each region is analyzed by calculating the return levels for periods of 6 months, 1 year, 3 years, and 5 years. Results: The Mapo (MP) area revealed the most unhealthy days, followed by Gwanak (GW) and Yangcheon (YC). On the contrary, the number of unhealthy days was low in Seodaemun (SDM), Songpa (SP) and Gangbuk (GB) areas. The return level of PM2.5 was high in Gangnam (GN), Dongjak (DJ) and YC. It will be necessary to prepare for PM2.5 than other regions. On the contrary, Gangbuk (GB), Nowon (NW) and Seodaemun (SDM) showed relatively low return levels for PM2.5. However, in most of the regions of Seoul, PM25 is generated at a very poor level ($75{\mu}g/m^3$) every 6months period, and more than $100{\mu}g/m^3$ PM2.5 occur every 3 years period. Most areas in Seoul require more systematic management of PM2.5. Conclusion: In this paper, accurate prediction and analysis of high concentration of PM2.5 were attempted. The results of this research could provide the basis for the Seoul Metropolitan Government to establish policies for reducing PM2.5 and measuring its effects.

A Study of the Diversity and Profile for Extracellular Enzyme Production of Aerobically Cultured Bacteria in the Gut of Muraenesox cinereus (갯장어(Muraenesox cinereus) 장으로부터 호기적 조건에서 분리된 미생물의 다양성 및 세포외 효소 생산능 분석에 관한 연구)

  • Lee, Yong-Jik;Oh, Do-Kyoung;Kim, Hye Won;Nam, Gae-Won;Sohn, Jae Hak;Lee, Han-Seung;Shin, Kee-Sun;Lee, Sang-Jae
    • Journal of Life Science
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    • v.29 no.2
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    • pp.248-255
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    • 2019
  • This research confirmed the diversity and characterization of gut microorganisms isolated from the intestinal organs of Muraenesox cinereus, collected on the Samcheonpo Coast and Seocheon Coast in South Korea. To isolate strains, Marine agar medium was basically used and cultivated at $37^{\circ}C$ and pH7 for several days aerobically. After single colony isolation, totally 49 pure single-colonies were isolated and phylogenetic analysis was carried out based on the result of 16S rRNA gene DNA sequencing, indicating that isolated strains were divided into 3 phyla, 13 families, 15 genera, 34 species and 49 strains. Proteobacteria phylum, the main phyletic group, comprised 83.7% with 8 families, 8 genera and 26 species of Aeromonadaceae, Pseudoalteromonadaceae, Shewanellaceae, Enterobacteriaceae, Morganellaceae, Moraxellaceae, Pseudomonadaceae, and Vibrionaceae. To confirm whether isolated strain can produce industrially useful enzyme or not, amylase, lipase, and protease enzyme assays were performed individually, showing that 39 strains possessed at least one enzyme activity. Especially the Aeromonas sp. strains showed all enzyme activity tested. This result indicated that isolated strains have shown the possibility of the industrial application. Therefore, this study has contributed for securing domestic genetic resources and the expansion of scientific knowledge of the gut microbial community in Muraenesox cinereus of South Korea.

Species Composition of Benthic Macroinvertebrates and Water Evaluation Using Their Species in the Songji River in Korea (한국 송지천에서 저서성대형무척추동물의 종조성과 이를 이용한 수질 평가)

  • Lee, Byeong Ryong;Huh, Man Kyu
    • Journal of Life Science
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    • v.29 no.5
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    • pp.580-587
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    • 2019
  • Benthic macroinvertebrates were analyzed in March, June, September, and December 2018 to evaluate water quality in the Songji River in Sacheon-ci, Korea. The identified benthic macroinvertebrates included 447 individuals belonging to 20 species, 18 families, 12 orders, 5 classes, and 3 phyla. Various ecological parameters were estimated for evaluation of the river status. The total ecological score of benthic macroinvertebrate community (TESB) varied from 17 (Station D) to 41 (Station A). The saprobic index and ecological score of benthic macroinvertebrate community (ESB) for the evaluation of river status revealed a water quality evaluation at Station A of II (oligosaprobic), indicating some satisfactory water protection. The benthic macroinvertebrate index (BMI) varied from 25.207 (Site C) to 39.348 (Station A). The evaluation of the river status at Stations C and D was polysaprobic, and sensitive taxa were absent. The mean Shannon-Weaver index (H') of diversity varied from 1.288 (Station D) to 2.250 (Station A). The classification of saprobity based on H' was ${\beta}$-mesosaprobic at Station A and ${\alpha}$-mesosaprobic at the other stations. The value of geometric density was varied from 1.229 (Station A) to 2.071 (Station D), with a mean of 1.582. An artificial load is being added to this river. One of load is the rectal river construction which flows straight through the river physics. Thus, the environment of living organisms deteriorates due to insufficient water. In order to secure the quality of the Songji River and a good environmental habitat, several low-height stepped-beam structures are required.

Effects of Overall Shading and Partial Shading on the Response of Chlorophyll Fluorescence of Soybean (전면적차광과 부분차광이 콩 엽록소 형광 반응에 미치는 영향)

  • Cho, Yuna;Jo, Euni;Jeong, Jae-Hyeok;Yoon, Changyong;An, Kyunam;Cho, Jaeil
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.23 no.3
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    • pp.163-168
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    • 2021
  • The growth experiment under shading condition has been performed to understand the eco-physiological responses of crops to light in terms of photosynthesis. There are two types of shading: overall shading and partial shading. In this study, the chlorophyll fluorescence of soybean was observed under the overall shading of the box made by polyresin and the partial shading at agrivoltaic system. The overall shading condition during vegetative growth induced lower SPAD and Electron transport rate (ETR). These lower values recovered after removal of shading box. However, the Non-photochemical fluorescence quenching (NPQ) became lower under overall shading and higher under partial shading. Such increase in NPQ limited crop photosynthesis even though the ETR was almost same to the control without shading treatment. Under the condition of partial shading, the values of SP AD and ETR for soybean did not change. However, the NPQ was higher than control condition. This suggests that the crop photosynthesis under both types of shading would be decreased by different eco-physiological processes which are the lower ETR in overall shading and the higher NP Q in partial shading despite the reduced light under shading conditions.