• Title/Summary/Keyword: Distribution Department

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Phototaxis of Fish 4. Response of Gray Rock Cod and Cat Shark to the White Lights (어류의 주광성에 관한 연구 4. 백색광에 대한 볼낙과 두툽상어의 반응)

  • YANG Yong-Rhim
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.14 no.2
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    • pp.59-65
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    • 1981
  • The purpose of the present study is to find the light intensity which induces maximum gathering rate and to observe the variation of the gathering rate both in daytime and at night by rising two species of commercial fishes: gray rock cod. Sebastes inermis (Cuvier et Valenciennes) and cat shark, Scyliorhinus torazame (Tanaka). An experimental tank $(360L\;{\times}\;50W\;{\times}\;55H\;cm)$ was set up in a dark room. An illumination system was attached to one end of the tank to control horizontal light intensity. Six artificial light sources were prepared by combination of two light bulbs (5W, 150W) and seven filters. During the experiment water depth was maintained 50 cm level in the tank. The tank was marked into six longitudinal sections each being 60 cm long to observe the distribution of fish. The fish were acclimatized in dark condition for 40 minutes prior to the main experiment. Upon turning on the light, the number of fish in each section was counted 40 times every 30 seconds, and the gathering rates were obtain from the average number of fish in each section. The light intensity inducing maximum gathering rate is as follows: gray rock cod: 16.6 lux (10.6-24.5 lux) (day), 0.7 lux (0.5-1.1 lux) (night), cat shark: 1.9 lux (1.2-2.9 lux) (day), 16.6 lux(10.6-24.5lux) (night). Trend of the gathering rate in illumination time revealed different results in two fish species. Gathering rate of gray rock cod did not show any definite pattern but fluctuated irregularly. The gathering rate was some fluctuating at night. However, that of cat shark was almost constant and did not show any distinctive difference between day and night.

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Seasonal Variations of Seaweed Community Structure at the Subtidal Zone of Bihwa on the East Coast of Korea (동해 비화 조하대 해조류 군집구조의 계절적 변화)

  • Kim, Young-Dae;Park, Mi-Seon;Yoo, Hyun-Il;Min, Byung-Hwa;Jin, Hyung-Joo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.45 no.3
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    • pp.262-270
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    • 2012
  • Seaweeds provide habitats in which marine animals can spawn and develop, and serve as a food supply for algaegrazing species such as sea urchins and abalone. Recently, seaweed species have disappeared from coastal ecosystems, leaving barren ground, defined as habitats that have lost their algae forests and where coralline algae containing calcium carbonate components have become encrusted on rocks. The biological causes of barren ground include grazing by herbivores and excessive seaweed harvest. The environmental harm caused by the spread of barren ground includes accelerated eutrophication following the reduction in seaweed, which plays an important role in oceanic purification. In the present study, we identified the relationships between various seaweed species and the occurrence of barren ground. Subtidal benthic macroalgal flora and community structure were observed seasonally on barren ground along vertical transects of rocky shores of Bihwa, Samchuck, and the east coast of Korea from February to November 2006. Fifty-eight seaweed species were identified, including 7 green, 15 brown, and 36 red algae species. There were between 6 and 28 species among seasons. Over the whole study period, average seaweed biomass (g wet wt $m^{-2}$) was 241.90 g, with a seasonal range of 25.26 to 760.34 g. Seaweed biomass declined with increasing seawater depth and ranged between 91.26 and 422.08 g. The vertical distribution of algae was characterized by Undaria pinnatifida and Sargassum honeri at 5 m, S. honeri and U. pinnatifida at 10 m, and U. pinnatifida and Agarum clathratum at 15 m depth. Seasonal patterns in community indices were not found. Community indices showed different patterns along vertical shoreline gradients; the dominance index increased but the richness, evenness, and diversity indices decreased with seawater depth. Sea urchin density was 8 to 24 individ. $m^{-2}$ in Bihwa. These urchin populations had significantly aggregated spatial patterns and recurrent destructive grazing appeared to be occurring.

Utility of the Dispatch Protocol to Triage the Emergency Patients who presented with Symptoms of Stroke or Chest Pain (흉통 및 뇌졸중 증상 환자에 대한 전화 중증도분류 지침의 유용성)

  • Cho, Suck-Ju;An, Byeung-Ki;Park, Jae-Yong
    • The Journal of the Korea Contents Association
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    • v.12 no.12
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    • pp.345-355
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    • 2012
  • Delayed treatment of acute cardiovascular and cereb-directrovascular diseases is related to poor prognosis and sequelae. For rapid and adequate treatment, role of prehospital emergency dispatchers for adequate triage and selection of hospital is important. In several advanced countries, emergency dispatchers use standardized protocols for decision of rescuer resources or distribution of patients at each hospital. ut, there has not been developed standardized protocol for emergency dispatchers in Korea. We developed standardized protocol based on NHS-direct and CTAS system for triage of symptoms of chest pain and Stroke. Groups with standardized protocol and without protocol was compared to triage result at emergency department which patient visited. The accuracy of triage on chest pain was 70.0% in group A, 94.0% in group B(p<0.01). The accuracy of triage in stroke symptoms was 64.2% in group A, 84.6% in group B(p<0.01). Conclusion: In this study, the accuracy of telephone triage with the protocol was more accurate than without the protocol. But, more studies are needed to generalize the protocol in South korea.

Extraction of Micro Filler from Bio-waste Material (Bio waste 소재로부터의 마이크로 필러 추출)

  • Nam, Gibeop;Song, Jung-Il
    • Composites Research
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    • v.31 no.5
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    • pp.209-214
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    • 2018
  • This paper explain about the development of environmental friendly, low cost and stable supply material i.e., rice husk and shell were used as micro incorporating bio waste filler. Those were processed by ball mill and analyzed through micro observation by FE-SEM, EDS and particle size distribution. The obtained filler was mixed with epoxy resin for the manufacturing of CFRP composite and study tensile properties. In EDS analysis main contents of rice husk and rice husk ash are C, O and Si. When rice husk was burned C and Si ration were increased. Shell powder has C, O and Ca. It caused $CaCO_3$ from shell. Surface weighted mean of rice husk powder is $6.19{\mu}m$ and volume weighted mean is $14.77{\mu}m$. And it has rod type particles which caused hair and husk structure parts. Surface weighted mean of rice husk ash powder is $1.55{\mu}m$ and volume weighted means is $8.20{\mu}m$. Surface weighted mean of shell powder is $2.53{\mu}m$ and volume weighted mean is $5.79{\mu}m$. The tensile decreased with increasing the content of micro filler in CFRP composites. In case of rice husk, the significant decrement of tensile strength was observed. and in case of shell powder, there is no effect of changes take place in tensile strength.

Involvement of a LiCl-Induced Phosphoprotein in Pigmentation of the Embryonic Zebrafish (Danio rerio) (LiCl에 의해 유도되는 phosphoprotein이 embryonic zebrafish (Danio rerio)의 pigmentation에 미치는 영향)

  • Jin, Eun-Jung;Thibaudeau, Giselle
    • Journal of Life Science
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    • v.18 no.9
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    • pp.1219-1224
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    • 2008
  • The embryonic zebrafish (Danio rerio) is rapidly becoming an important model organism for studies of early events in vertebrate development. Neural crest-derived pigment cell precursors of the embryonic zebrafish give rise to melanophores, xanthophores, and/or iridophores. Cell-signaling mechanisms related to the development of pigmentation and pigment pattern formation remain obscure. In this study, zebrafish embryos were treated with various signaling-related molecules - LiCl (an inositol-phosphatase inhibitor), forskolin (a protein kinase-A activator), a combination of LiCl/forskolin, and LiCl/heparin (an IP3 inhibitor) in order to identify the mechanisms involved in pigmentation. LiCl treatment resulted in ultrastructural and morphological alterations of melanophores. To identify the possible proteins responsible for this ultrastructural and morphological change, phosphorylation patterns in vitro and in vivo were analyzed. LiCl and LiCl/forskolin treatment elicited dramatic increases in the phosphorylation of a 55-kDa protein which was inhibited by heparin treatment. LiCl treatment also induced phosphorylation of a 55-kDa protein in melanophores purified from adult zebrafish. Collectively these results suggest that a LiCl-induced 55-kDa phosphoprotein plays a role in melanophore morphology and ultrastructure and ultimately effects gross pigmentation.

Incidence of Wildfire Disease on Soybean of Korea during 2014-2015 (2014-2015년 국내 콩 들불병 발생 상황)

  • Kang, In Jeong;Kim, Seung-Han;Shim, Hyeong Kwon;Seo, Min Jeong;Shin, Dong Bum;Roh, Jae Hwan;Heu, Sunggi
    • Research in Plant Disease
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    • v.22 no.1
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    • pp.38-43
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    • 2016
  • Wildfire caused by Pseudomonas amygdali pv. tabaci has been seen a steady increase in the incidence and prevalence on soybean in Korea. But up to know there is no official report on the prevalence of the disease in Korea. The nationwide survey of the occurrence of soybean wildfire showed that 19 out of 30 regions in 2014 and 9 out of 28 regions in 2015 had been infected with P. amygdali pv. tabaci. The severity of wildfire varied according to the cultivar, cultivation regions and climates. However, cultivar seoeitae was susceptible in both 2014 and 2015. The disease severity of 2014 was twice that of 2015. Since the temperature of 2014 and 2015 were very similar but the precipitation of 2014 was more than twice that of 2015, the precipitation of 2014 had a great impact on the wildfire disease severity.

Comparison of Physiological Variables by Age Group in Drinking Men (음주남성의 나이대별 생리학적 변수들의 비교)

  • Hyun, Kyung-Yae
    • Journal of Life Science
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    • v.19 no.10
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    • pp.1374-1381
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    • 2009
  • This study was designed to investigate the differences of physiological variables by age group in alcohol-consuming men. The thirty year old-age group had the lowest waist-hip ratio (WHR), right and left cardio-ankle vascular index (R-CAVI and L-CAVI), right and left ankle-brachial index (R-ABI and L-ABI), amylase, high sensitivity C-reactive protein (hs-CRP), and creatine phosphokinase (CPK) levels, and the highest body weight (BW), interleukin-6 (IL-6), right and left intraocular pressure (R-IP and L-IP), hematocrit (Hct), hemoglobin (Hb), erythrocyte, red blood cells distribution width (RDW), alanine aminotransferase (ALT), total cholesterol (TCH), triglyceride (TG), and ferritin levels. The forty year old-age group was the highest in hs CRp and CPK levels, but the lowest in ferritin level. The fifty year old-age group possessed the highest WHR, diastolic blood pressure (DBP), R- and L-ABI, eosinophil, and amylase levels. The sixty year old-age group had the highest R- and L-CAVI, mean corpuscular volume (MCV), ALP, $\gamma$-glutamyltranspeptidase ($\gamma$-GTP), rheumatoid factor (RF), $\alpha$-fetoprotein (AFP) and prostate specific antigen (PSA) levels and the lowest BW, DBP, R-IP, L-IP, Hct, Hb, leukocyte, platelet, RDW, eosinophil, monocyte, ALT, amylase, TG, and CPK levels. These findings indicate that there may be differences of physiological variables depending on age group in alcohol-consuming men. Further studies should be focused on the physiological differences between alcohol-consuming men and women.

Endophytes from Natural Festuca spp. in Southwest China and Their Compatibility with Tall Fescue Cultivars (남서중국의 자생페스큐의 엔도파이트와 톨체스큐 품종과의 공생)

  • Wang, Yaoyao;Du, Yongji;Han, Liebao;Li, Deying
    • Asian Journal of Turfgrass Science
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    • v.23 no.1
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    • pp.163-176
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    • 2009
  • Investigating endophyte distribution, naturally occurring in native grasses, is important for understanding endophyte-grass associations and using the beneficial effects of endophytes in cultivated plants. The goal of this study was to investigate endophytes from natural Festuca spp. in Yunnan, Guizhou, and Sichuan Provinces of China, and to study the compatibility between the endophytes and turf type tall fescue (Festuca arundinacea) which is widely used for lawn and athletic fields in that region. Of 628 accessions in F. ovina, 421 had endophytes identified in leaf sheath from on-site microscopic examination. From Festuca spp, three isolates were obtained from the seeds and ninety isolates were obtained from seedlings established from the collected seeds. The isolates from F. ovina and F. stapfii were tentatively identified as Neotyphodium typhinum and Neotyphodiumstarii, respectively. We tested compatibility of the two fungal species with seven tall fescue cultivars, Little Hero, Sub Boy, Eldorado, Arid III, Millennium, Crossfire, and Fawn. N. typhinum or N. starii did not infect 'Fawn' with either seed injection or seed soaking method. The highest infection rate byboth N. typhinum and N. starii was in 'Sun Boy' and 'Eldorado'. There were significant interaction effects between tall fescue cultivar and type of endophyte on infection.

Distribution of Water Temperature and Common Squid Todarodes pacificus Paralavae around Korean Waters in 2013, 2014 (2013-2014년 한국주변해역 수온과 살오징어 유생분포)

  • Kim, Yoon-Ha;Lee, Chung Il
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.22 no.1
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    • pp.11-19
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    • 2016
  • Field observation for oceanic conditions and paralarvae of the common squid, Todarodes pacificus in Korean waters were sampled with the Bongo net (diameter: 60 cm, mesh size: $333{\mu}m$) by using oblique tow method with the oceanographic research vessel (Tamgu 12 and Tamgu 20) around Korean waters (middle of the Yellow Sea, northern part of the East China Sea, East Sea) in 2013 and 2014 was carried out. The observation in the Yellow Sea and the northern part of the East China Sea was done in August, 2013 and in the East Sea it was repeated at seven times from June, 2013 to September, 2014. The paralarvae in August of 2013 was not found in the Yellow Sea and one paralarvae was found in the northern part of the East China Sea. In the East Sea, 39 paralarvae during whole observation period were found, mantle length of paralarvae was from 1.7 to 13.5 mm. Surface water temperature in the Yellow Sea was $30^{\circ}C$, and cold water mass lower than $10^{\circ}C$ was occupied in the deep layer than 30 m. In the northern part of the East China Sea, surface water temperature was $31^{\circ}C$, and higher water temperature above $20^{\circ}C$ was found in deeper than 50 m. In the East Sea, optimum temperature for survival, $15-24^{\circ}C$, was existed shallower than 75 m.

An Analysis on Mediating Effect of Participant Activity in Investment Crowdfunding (투자형 크라우드펀딩에서 참여자활동성의 매개효과 분석)

  • Kim, Jong Yun;Kim, Chul Soo
    • The Journal of Society for e-Business Studies
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    • v.25 no.1
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    • pp.65-82
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    • 2020
  • Start-ups often use crowdfunding platforms such as Wadiz to get financing from corporate investors and general public. These platforms include functions to increase participant activity through the number of comments, interest and online word-of-mouth. This study aims to elucidate how these functions related to a participant activity exhibit mediating effects on a success of crowdfunding and an achievement rate of targeted investment amount. To this end, the individual variables such as progress period, target amount, venture company, experience of attracting investment, possession of intellectual property rights, a career of the representative and an award experience of the representative were classified into the project characteristics, the company characteristics and the representative characteristics through not only previous studies but also interviews with investment professionals and platform operators. Afterwards, this study went through an empirical verification process using a structural equation model that has both crowdfunding performance and participant activity, which is the independent and mediating factors of three perspectives, as well as the dependent variables. In other words, this study analyzes how the characteristics of three perspectives affect the participant activity and how the participant activity had the mediating effects on the crowdfunding performance. In addition, it derives how the analysis results mentioned above vary according to business types (internet services, culture/art, manufacturing/distribution) and investment styles (stock type and bond type). It is expected that this study will help not only in deriving the factors affecting the performance of an investment type crowdfunding but also in preparing the measures to increase a participant activity.