• 제목/요약/키워드: Marine science

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선박사고 기인 해양재난 피해축소를 위한 해양과학기술 개발수요 도출

  • 장덕희;강길모
    • 한국기술혁신학회:학술대회논문집
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    • 한국기술혁신학회 2015년도 춘계 학술대회 논문집
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    • pp.508-525
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    • 2015
  • The purpose of this study is to derive the demands to develop marine science technology to reduce damage of disasters caused by boating accidents. This study analyzed the press release to identify the factors of damages that can result from boating accidents and derive the demands for technology development to approach from the perspective of marine science technology to avoid the elements of damage. For this purpose, this study analyzed the contents of about 77,000 articles posted for a month after the tragedy of the Sewol (April 16 - May 15) to derive the keywords and used SNA for the network analysis of each keyword. The findings of the analysis showed that there were five networks and each network consisted of different aspects of technology development to prepare for the marine disasters. Based on these findings, this study derived the demands for technology development from the perspective of marine science technology required to prepare for the possible marine disasters caused by vessels in the future.

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Potential applications of radioprotective phytochemicals from marine algae

  • Oh, Jae-Young;Fernando, I.P. Shanura;Jeon, You-Jin
    • ALGAE
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    • 제31권4호
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    • pp.403-414
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    • 2016
  • The use of ionizing radiation and radioactive elements is becoming increasingly popular with the rapid developments in nuclear technology, radiotherapy, and radio diagnostic methods. However, ionizing radiation can directly or indirectly cause life-threatening complications such as cancer, radiation burns, and impaired immunity. Environmental contamination with radioactive elements and the depletion of ozone layer also contribute to the increased levels of radiation exposure. Radioprotective natural products have particularly received attention for their potential usefulness in counteracting radiation-induced damage because of their reduced toxicity compared with most drugs currently in use. Moreover, radioprotective substances are used as ingredients in cosmetic formulations in order to provide protection against ultraviolet radiation. Over the past few decades, the exploration of marine algae has revealed the presence of radioprotective phytochemicals, such as phlorotannins, polysaccharides, carotenoids and other compounds. With their promising radioprotective effects, marine algae could be a future source for discovering potential radioprotective substances for development as useful in therapeutics.

Molecular Phylogeny Reconstruction of Grouper (Serranidae: Epinephelinae) at Northern Part of Bird's Head Seascape - Papua Inferred from COI Gene

  • Tapilatu, Ricardo F.;Tururaja, Tresia Sonya;Sipriyadi, Sipriyadi;Kusuma, Aradea Bujana
    • Fisheries and Aquatic Sciences
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    • 제24권5호
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    • pp.181-190
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    • 2021
  • Grouper is one of the most economically important fishes with various morphological forms and characteristics, meaning it is often difficult to identify species and distinguish between life stages, sometimes leading to morphological misidentification. Therefore, identification using a molecular deoxyribose nucleic acid (DNA) approach was needed as an alternative means to identify closely related species. This study aims to determine the molecular phylogeny of grouper from the northern part of the Bird's Head Seascape of Papua. The DNA sequence of each cytochrome oxidase I (COI) gene was used to study the molecular relationship among closely related species of grouper. The results showed that there were 16 Epinephelinae that have been compared to a gene bank (National Centre for Biotechnology Information, NCBI) in the sequence length of 623 base pairs. The closest genetic distance was found between Cephalopholis miniata and Cephalopholis sexmaculata (0.036), while the furthest genetic distance was observed between Plectropomus laevis and Cephalopholis spiloparaea (0.247). This finding was further reinforced by the morphological characters of each species. This finding highlighted that five genera were represented as a monophyletic group (clade), i.e., Epinephelus, Cephalopholis, Plectropomus, Saloptia and Variola.

Marine Algicolous Endophytic Fungi - A Promising Drug Resource of the Era

  • Sarasan, Manomi;Puthumana, Jayesh;Job, Neema;Han, Jeonghoon;Lee, Jae-Seong;Philip, Rosamma
    • Journal of Microbiology and Biotechnology
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    • 제27권6호
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    • pp.1039-1052
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    • 2017
  • Endophytic fungi have currently been acknowledged as the most promising source of bioactive compounds for drug discovery, and considerable progress has been made in exploring their diversity, species richness, and bioprospecting. Fungal endophytes from unique environmental settings offer a pool of potentially useful medicinal entities. Owing to the constant stresses imposed on macroalgae by marine environments, it is believed that algae and their associated endophytic symbionts represent a good source of structurally diverse bioactive secondary metabolites. Despite the proven significance of active metabolites of algal endophytes, little have been exploited. This review highlights the latest discoveries in algicolous endophytic research, with particular focus on the bioactive metabolites from algal endophytes. Compounds are classified according to their reported biological activities, like anticancer, antibacterial, antifungal, and antioxidant properties. Present experimental evidence suggests that a majority of the bioactive metabolites were reported from Phaeophyceae followed by Rhodophyceae and Chlorophyceae. An intensive search for newer and more effective bioactive metabolites has generated a treasure trove of publications, and this review partially covers the literature published up to 2016.

자란만 패류양식해역의 물리환경 설명을 위한 평균체류시간 산정 (Assessing Average Residence Time as a Physical Descriptor for Shellfish Farming Areas in Jaran Bay, Korea)

  • 김진호;박성은;김영민;김청숙;강성찬;정우성;심보람;엄기혁
    • 한국환경과학회지
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    • 제29권3호
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    • pp.273-282
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    • 2020
  • Residence time is defined as the time taken for a material in a system to leave the system. The residence time characteristics in shellfish aquaculture determine the dispersion of excretion from aquaculture farms, along with the supply of food by seawater exchange. In this study, we estimated the spatial distribution of average residence time in the shellfish farming area using a particle tracking model. As a result, a relatively short average residence time of about 20 days or less was calculated in most areas, but an average residence time of more than 40 days was calculated in the inner areas. Relatively long average residence times were calculated along the west coast compared to the east coast, with the longest average residence time of more than 50 days in the northwestern areas. It can be inferred that the disturbance of the benthic ecosystem caused by shellfish farms is likely to be large because of the relatively weak dispersion of excrement from shellfish farms located on the west coast, especially in the northwest region. This distribution of average residence time is important for understanding the potential effects of seawater exchange on the environmental sustainability of shellfish farms, along with the seawater circulation characteristics of Jaran Bay.

2011-2020년간 목시조사에 의한 우리나라 연근해 해양포유류 출현 및 분포 현황 (Occurrence and Spatial Distribution of Marine Mammals by Sighting Surveys in Korean Waters During 2011-2020)

  • 이종희;김은호;이경리;박겸준;안용락;김현우;손호선;최석관
    • 한국수산과학회지
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    • 제55권6호
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    • pp.938-945
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    • 2022
  • National Institute of Fisheries Science conducted a total of 39 sighting surveys for marine mammals over 624 sighting days that covered 20,771 nautical miles in Korean waters during 2011-2020. Marine mammals were detected when 83.9% of the marine environment was less than or equal to three on the Beaufort wind scale. Thirteen species of marine mammals were identified, including two species of pinniped, with a majority of cetacean species. Frequently found species were narrow-ridged finless porpoise, followed by common dolphin, minke whale, Dall's porpoise, and Pacific white-sided dolphin. Narrow-ridged finless porpoises and minke whales were located in and offshore around the Korean peninsula, common and Pacific white-sided dolphins were exclusively found in the East Sea for most seasons. The other marine mammals were spotted in some seas and for limited durations.

Effects of feeding poly-β-hydroxybutyrate enriched Artemia nauplii on the growth, digestibility and immunity of Pacific white shrimp (Penaeus vannamei) post-larvae

  • Suhyeok Kim;Jaebeom Shin;Hyunwoon Lim;Daehyun Ko;Gunho Eom;Jongho Lim;Yeonji Lee;Sera Choi;So Yun Park;Jeung-Yil Park;Kyeong-Jun Lee
    • Fisheries and Aquatic Sciences
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    • 제27권7호
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    • pp.447-455
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    • 2024
  • This study was conducted to investigate the effects of feeding Artemia nauplii enriched with poly-β-hydroxybutyrate (PHB) on Pacific white shrimp (Penaeus vannamei) post-larvae. A total 900 shrimp (initial average body weight: 2.50 ± 0.01 mg) were randomly distributed into 9 acrylic tanks (96 L) in triplicate groups. The Artemia reared in 0%, 0.25% and 0.50% PHB dissolved water (designated as Con, PHB25 and PHB50, respectively) were fed to the shrimp post-larvae for 14 days. The growth performance of shrimp was significantly higher in PHB25 and PHB50 groups than those in Con group. Survival was not significantly different among all the groups. Relative gene expressions of trypsin and amylase were significantly upregulated in PHB25 group than those of Con group. Relative gene expression of chymotrypsin was significantly upregulated in PHB25 and PHB50 groups compared to Con group. Relative gene expression of insulin-like growth factor-I was significantly upregulated in PHB25 group than in Con group. Relative gene expression of insulin-like growth factor-binding protein was significantly upregulated in both PHB25 and PHB50 groups than that of Con group. Relative expression of prophenoloxidase gene was significantly upregulated in PHB25 and PHB50 groups as compared to Con group. Relative expression of penaeidin-3a gene was significantly upregulated in PHB50 group as compared to Con group. This study demonstrated that PHB, as a functional nutritional enrichment for Artemia, improves the growth, digestibility and immunity of shrimp post-larvae.

DETECTION AND MASKING OF CLOUD CONTAMINATION IN HIGH-RESOLUTION SST IMAGERY: A PRACTICAL AND EFFECTIVE METHOD FOR AUTOMATION

  • Hu, Chuanmin;Muller-Karger, Frank;Murch, Brock;Myhre, Douglas;Taylor, Judd;Luerssen, Remy;Moses, Christopher;Zhang, Caiyun
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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    • pp.1011-1014
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    • 2006
  • Coarse resolution (9 - 50 km pixels) Sea Surface Temperature satellite data are frequently considered adequate for open ocean research. However, coastal regions, including coral reef, estuarine and mesoscale upwelling regions require high-resolution (1-km pixel) SST data. The AVHRR SST data often suffer from navigation errors of several kilometres and still require manual navigation adjustments. The second serious problem is faulty and ineffective cloud-detection algorithms used operationally; many of these are based on radiance thresholds and moving window tests. With these methods, increasing sensitivity leads to masking of valid pixels. These errors lead to significant cold pixel biases and hamper image compositing, anomaly detection, and time-series analysis. Here, after manual navigation of over 40,000 AVHRR images, we implemented a new cloud filter that differs from other published methods. The filter first compares a pixel value with a climatological value built from the historical database, and then tests it against a time-based median value derived for that pixel from all satellite passes collected within ${\pm}3$ days. If the difference is larger than a predefined threshold, the pixel is flagged as cloud. We tested the method and compared to in situ SST from several shallow water buoys in the Florida Keys. Cloud statistics from all satellite sensors (AVHRR, MODIS) shows that a climatology filter with a $4^{\circ}C$ threshold and a median filter threshold of $2^{\circ}C$ are effective and accurate to filter clouds without masking good data. RMS difference between concurrent in situ and satellite SST data for the shallow waters (< 10 m bottom depth) is < $1^{\circ}C$, with only a small bias. The filter has been applied to the entire series of high-resolution SST data since1993 (including MODIS SST data since 2003), and a climatology is constructed to serve as the baseline to detect anomaly events.

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