• Title/Summary/Keyword: Fucus

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Community-level facilitation by macroalgal foundation species peaks at an intermediate level of environmental stress

  • Scrosati, Ricardo A.
    • ALGAE
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    • v.32 no.1
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    • pp.41-46
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    • 2017
  • In rocky intertidal habitats, abiotic stress due to desiccation and thermal extremes increases with elevation because of tides. A study in Atlantic Canada showed that, at low elevations where conditions are benign due to the brief low tides, fucoid algal canopies (Ascophyllum nodosum and Fucus spp.) do not affect the structure of benthic communities. However, at middle and high elevations, where low tides last longer, fucoid canopies limit abiotic extremes and increase the richness (number of invertebrate and algal species, except fucoids) of benthic communities. Using the data from that study, this paper compares the intensity of facilitation and its importance (relative to all other sources of variation in richness) between middle and high elevations, which represent intermediate and high stress, respectively. Facilitation intensity was calculated as the percent increase in benthic richness between quadrats with low and high canopy cover, while the importance of facilitation was calculated as the percentage of variation in richness explained by canopy cover. Data for 689 quadrats spanning 350 km of coastline were used. Both the intensity and importance of facilitation were greater at middle elevations than at high elevations. As canopies do not affect benthic communities at low elevations, this study suggests that the facilitation-stress relationship at the community level is unimodal for this marine system. Such a pattern was found for some terrestrial systems dominated by canopy-forming plants. Thus, it might be ubiquitous in nature and, as further studies refine it, it might help to predict community-level facilitation depending on environmental stress.

Patterns of Interactions among Neighbor species in a High Intertidal Algal Community

  • Kim, Jeong-Ha
    • ALGAE
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    • v.17 no.1
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    • pp.41-51
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    • 2002
  • Three dominant rocky intertidal macroalgae, the fucoids Fucus gardneri and Pelvetiopsis limitata (Phaeophyta) and the red alga Mazzaella cornucopiae (= Iridaea cornucopiae) on the west coast of Vancouver Island, British Columbia, Canada were used in a series of field experiments to examine interspecific interactions. These experiments showed complex patterns which included an interchange of negative (inhibition) and positive (facilitation) interactions depending on neighbor distance. Less fucoid recruitment occurred in the plots with greater percent cover of a turfforming red alga, M. cornucopiae. However, experimentally removing Mazzaella turf (the turf was considered to be "blocking" fucoid recruits or "shading" growing recruits) did not increase recruitment. This result indicated that there may be another factor(s) involved in the survivorship of juvenile fucoids in the turf-removed plots. Morphological differences in adult plants between Mazzaella and the two fucoids resulted in another type of interaction; these began when fucoids successfully settled and grew nearby or within the red algal turf. By monitoring microhabitat at the individual plant level for two years, I found that survivorship of fucoid recruits showed different species-specific patterns. The patterns also varied as the microhabitat changed from Mazzaella turf edge to open space. For F. gardneri, longevity of P.limitata at all distances tested was similar. A reason for greater longevity of F. gardneri individuals at edge microhabitats may be that these sites have one side open to light and nutrients and another site that buffers them from desiccation and wave impact. In the Mazzaella-Fucus interaction, neighbor distance was a key factor in determining whether the outcome of the interaction would be competition or facilitation (or protection). This study provides experimental evidence that detectable biological interactions occur in this upper intertidal algal community where physical conditions are usually severe, and also indicates the importance of small scale examination in understanding macroalgal interactions in intertidal habitats.

Mechanisms of Competition betxeen Canopy-Forming and Turf-Forming Intertidal Algae

  • Kim, Jeong-Ha
    • ALGAE
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    • v.17 no.1
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    • pp.33-39
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    • 2002
  • Mechanisms of competition between two canopy algae and an understory alga were investigated by a field manipulative experiment using artificial thalli. The study was carried out in the upper intertidal zone at Nudibranch Point in Vancouver Island, British Columbia, Canada, where two fucoids, Fucus gardneri and Pelvetiopsis limitata, and a turf red alga, Mazzaella cornucopiae, were dominant in the algal community. The experiment was designed to test three hypotheses, shading, whiplash, and allelopathy, imposed by potential fucoid effects on M. cornucopiae. Only the shading effect was significant, indicating that adult fucoid thalli reduced. M. cornucopiae biomass underneath the fucoids. Results indicated that reversal of competitive dominance existed between F. gardneri and M. cornucopiae depending on the life history stage of the competitors. By including the turf alga's effects on the fucoids, the well-balanced and non-hierarchical interaction networks among the major macroalgae support the high likelihood of species coexistence in the community.

Marine macroalgae and associated flowering plants from the Keret Archipelago, White Sea, Russia

  • Garbary, David J.;Tarakhovskaya, Elena R.
    • ALGAE
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    • v.28 no.3
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    • pp.267-280
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    • 2013
  • The marine algal flora of the Keret Archipelago ($66^{\circ}$ N, $33^{\circ}$ E) in the White Sea, Russia was investigated during 2008. Over 250 algal records from more than 15 islands and several sites on the adjoining mainland produced a total of 62 algal species. This raised the total from 56 to 88 species of Chlorophyta (23 species), Phaeophyceae (31 species), Rhodophyta (33 species), and Tribophyceae (1 species) of which seven were new records or verifications of ambiguous records for the White Sea and 11 species are new for the Keret Archipelago. The new or confirmed records included species of Blidingia, Eugomontia, Prasiola, Rosenvingiella, and Ulothrix (Chlorophyta), Acrochaetium, Colaconema (Rhodophyta), and Vaucheria (Tribophyceae). Five species of flowering plants (Aster, Plantago, Triglochin, and Zostera) were associated with the macrophytic algal vegetation of the region. Five fucoid algae in Pelvetia, Fucus, and Ascophyllum provide a picture of a temperate flora. Regardless, the overall species richness is consistent with an arctic nature to the flora. This discrepancy is attributed to the 'filter' provided by the Barents Sea of the Arctic Ocean for post-glacial colonization of the White Sea.

Antioxidant Activity of Sulfated Polysaccharides Isolated from Sargassum fulvellum

  • Choi, Dae-Sung;Athukorala, Yasantha;Jeon, You-Jin;Senevirathne, Mahinda;Cho, Kyun-Rha;Kim, Soo-Hyun
    • Preventive Nutrition and Food Science
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    • v.12 no.2
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    • pp.65-73
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    • 2007
  • Sargassum fulvellum, a marine brown alga, is a popular low priced edible plant in Korean markets. The polysaccharide fraction of the alga was separated and investigated for its radical scavenging activities and the results compared with those of commercial fucoidans (Fucus vesiculosus and Undaria pinnatifida), BHA and ${\alpha}$-tocopherol. The polysaccharide fraction of S. fulvellum showed a promising DPPH radical scavenging activity than did other fucoidans. Moreover, the sample exhibited a dose-dependent activity on hydrogen peroxide scavenging activity in the V79-4 cell line. Interestingly, all the tested polysaccharide counterparts were more potent NO. scavengers than were the commercial antioxidants, BHA and ${\alpha}$-tocopherol. The sulfated polysaccharide of S. fulvellum had an approximate molecular weight of 529 kDa and mainly consisted of fucose and galactose, and minor amounts of mannose, rhamnose and xylose.

Effect of Fucoidan on Expression of Diabetes Mellitus Related Genes in Mouse Adipocytes

  • Kim, Kui-Jin;Lee, Ok-Hwan;Lee, Han-Chul;Kim, Young-Cheul;Lee, Boo-Yong
    • Food Science and Biotechnology
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    • v.16 no.2
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    • pp.212-217
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    • 2007
  • Fucoidan (fucan sulfate) is a fucose-containing sulfated polysaccharide from brown algae such as Fucus vesiculosus, Ecklonia kurome, and Cladosiphon okamuranus. The aim of this study was to investigate the effect of fucoidan on the expression of diabetes-related genes in mouse cell line 3T3-L1. 3T3-L1 adipocytes were cultured for 48 hr with or without fucoidan (10, 100, and 500 ppm) on a 60 mm dish. Reverse transcription polymerase chain reaction (RT-PCR) was used for measurement of peroxisome proliferators activated receptor ${\gamma}\;(PPAR{\gamma})$, CCAAT/enhancer binding protein ${\alpha}\;(C/EBP{\gamma})$, and glucose transporter 4 (GLUT4) RT-PCR analysis revealed that expression level of GLUT4, $PPAR{\gamma}$, and $C/EBP{\alpha}$ mRNAs increased with fucoidan treatment from 10 to 500 ppm in a dose-dependent manner. Fucoidan appears to enhance insulin sensitivity by increasing the expression level of diabetes-related genes in 3T3-L1 adipocytes. Therefore, fucoidan is potentially useful as a natural therapeutic material for hyperglycemia in type II diabetes patients.

Automatic Test Report Recording Program Design and Implementation for Integration Test (통합시험을 위한 자동 시험일지 작성프로그램 설계 및 구현)

  • Jeong, Younghwan;Song, Kyoungrok;Lee, Wonsik;Wi, Sounghyouk
    • KIISE Transactions on Computing Practices
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    • v.24 no.1
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    • pp.33-39
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    • 2018
  • For the integration test in the current field of defense simulation, each actual equipment and simulator's logging information is automated. Although the event of the integrated test system is written in the test log, it is not automated, and relies on the operator's handwriting or file creation, resulting in ineffective aspects such as low-quality record content and repetition of the same content. In this study, we propose the automatic test report recording program that solves these problems. Automatic test report recording program uses framework-based technology to receive information from the test control computer and user to record a log of the test log. Automatic test report recording program allows the user to record the repeated test content in a stable manner. Additionally, even if the number of test operators is limited, the efficiency is improved so that we can fucus on the integration test.

Immunomodulating Activity of a Fucoidan Isolated from Korean Undaria pinnatifida Sporophyll

  • Yoo, Yung-Choon;Kim, Woo-Jung;Kim, So-Yeon;Kim, Sung-Min;Chung, Mi-Kyung;Park, Joo-Woong;Suh, Hyun-Hyo;Lee, Kyung-Bok;Park, Yong-Il
    • ALGAE
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    • v.22 no.4
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    • pp.333-338
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    • 2007
  • A fucoidan, isolated from Korean Undaria pinnatifida spoprophyll (UP-F), was investigated for its immunomodulating activity on murine macrophages and splenocytes, and its activity was compared with that of fucoidan from Fucus vesiculosus (FV-F). Treatment of UP-F resulted in inhibition of the growth of murine macrophage RAW 264.7 cells, but its cytotoxicity was not observed in normal murine splenocytes. FV-F was shown to be highly cytotoxic to both immune cells, and its cytotoxic activity was higher than that of UP-F. Treatment of UP-F induced TNF-α in a dose-dependent manner from two types of macrophages, RAW 264.7 cells and murine peritoneal macrophages. The TNF-α-inducing activity of UP-F was higher than that of FV-F. UP-F also actively induced chemokines (RANTES and MIP-1α) from RAW 264.7 cells. Furthermore, treatment of UP-F gave rise to activation of murine splenocytes to produce cytokine (IL-6) and chemokines (RANTES and MIP-1α), showing significantly higher activity than that of FV-F. These results indicate that UP-F is less cytotoxic to immune cells than FV-F, and possesses immunomodulating activity to produce cytokines and chemokines from macrophages and splenocytes.

A Clinical Review of the Patients in the Kim Chan Pain Clinic (김 찬 신경통증클리닉 환자의 통계고찰)

  • Han, Kyung-Ream;Park, Won-Bong;Kim, Wook-Seoung;Lee, Jae-Cheul;Lee, Kyung-Jin;Kim, Chan
    • The Korean Journal of Pain
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    • v.11 no.1
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    • pp.101-104
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    • 1998
  • Backgrouds: Twent five years have passed since the opening of the first pain clinic in korea, in 1973 at Yonsei University Hospital. The number of pain clinics are gradually increasing in recent times. It is important to plan for future pain clinics with emphasis on improving the quality of pain management. Therefore we reviewed the patients in our hospital to help us in planning for the future of our pain clinic. Methods: We analyzed 2656 patients who had visited our Kim Chan Pain Clinic, accordance to age, sex, disease, and type of treatment block, from July 1996 to August 1997. Results: The prevalent age group was in the fifties, 27.3%, seventy years and older compromised 9.2%. The most common disease were as follows: lower back pain(46.2%); cervical and upper extremities pain(23.1%); trigeminal neuralgia(7.2%); and hyperhydrosis(5.8%) Both nerve blocks and medication were prescribed as treatment. Lumbar epidural block(16.3%) and stellate ganglion block(15.6%) were the most frequent blocks performed among various nerve blocks. Among nerve block under C-arm guidance, lumbar facet joint block(24.4%) and lumbar root block(22.5%) were performed most frequently. Trigeminal nerve block(18.4%), thoracic(17.0%) and lumbar sympathetic ganglion block(11.4%) were next most prevalent blocks performed frequent block. Conclusions: Treatments at our hospital were focused on nerve blocks and medications prescriptions. Nerve blocks are of particular importance in the diagnosis and treatment of chronic pain. However in future, to raise the quality of pain management, we need to fucus on a multidisciplinary/interdisciplinary team approach.

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Population ecology of Palmaria palmata (Palmariales, Rhodophyta) from harvested and non-harvested shores on Digby Neck, Nova Scotia, Canada

  • Garbary, David J.;Beveridge, Leah F.;Flynn, Andrea D.;White, Katelyn L.
    • ALGAE
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    • v.27 no.1
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    • pp.33-42
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    • 2012
  • Population ecology of Palmaria palmata is described from the intertidal zone of Digby Neck and adjacent islands of Nova Scotia. The primary objectives were: to evaluate the difference in habitat specialization and population structure of P. palmata between harvest and non-harvest shores, and to characterize differences in thallus structure and frond sizes between epilithic and epiphytic populations. Harvest shores were gently sloping boulder fields with boulders typically about 0.5-1.0 m with dense cover of P. palmata on many of the rocks. Non-harvest shores (with or without P. palmata) consisted of boulders that were smaller or larger than harvest shores, or bedrock; when P. palmata was present on nonharvest sites it was typically epiphytic on other algae (e.g., Fucus spp., Mastocarpus stellatus, Devaleraea ramentacea). Harvestable epiphytic populations occurred only in high current areas. While there was little difference in average cover of P. palmata harvest and non-harvest shores ($31.2{\pm}13.7%$ vs. $19.4{\pm}7.3%$, mean ${\pm}$ standard deviation [SD]), the cover of P. palmata on harvest shores was highly skewed such that individual boulders often had >90% cover while adjacent rocks had little. Frond length of large fronds was greater on harvested shores, and mean frond density ($g\;m^{-2}$) was three times higher than the mean density on the non-harvested shores. Frond lengths of entire epiphytic and epilithic frond complements of 119 thalli from harvest beaches showed no difference in mean size of the largest fronds, and no difference in frond number per holdfast when epiphytic and epilithic thalli were compared.