• 제목/요약/키워드: Density-dependant growth

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Year-to-Year and Inter-Decadal Fluctuations in Abundance of Pelagic Fish Populations in Relation to Climate-Induced Oceanic Conditions

  • Gong, Yeong;Suh, Young-Sang;Han, In-Seong;Seong, Ki-Tack
    • Journal of Ecology and Environment
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    • 제31권1호
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    • pp.45-67
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    • 2008
  • Ocean climate variables ($1900{\sim}2005$), time series of catches ($1910{\sim}2005$) and body size data were used to assess the year-to-year and decadal scale fluctuations in abundance of the fish populations (Japanese sardine, anchovy, jack mackerel, chub mackerel, Pacific saury and common squid) that have spawning grounds in the East China Sea and its adjacent regions. A negative correlation between the abundance of pelagic fishes (e.g. jack mackerel) in the Tsushima Warm Current (TWC) region and the Kuroshio-Oyashio Current (KOC) region was attributed to the climatic modulation of larval transport and recruitment, which depends on the winter monsoon-induced drift, current systems, and spawning season and site. The changes in abundance and alternation of dominant fish populations in the two regions in the 1930s, 1970s, and late 1980s mirrored changes in the climate indices (ALPI, AOI and MOI). Oscillations in the decadal climate shifts between the two regions led to zonal differences in larval transport and recruitment, and hence differences in the abundance of the pelagic fish populations. During deep Aleutian Lows, as in the 1980s, larval transport from the East China Sea to the KOC region increases in association with the strong winter Asian monsoon, cool regime and increased volume transport of the Kuroshio Current systems, whereas during a weak Aleutian Low (as in the 1990s), larval transport to the TWC region increased in association with a weak winter Asian monsoon, a warm regime, and increased volume transport of the Tsushima current system. We postulate that the increased chub mackerel abundance in the TWC region and the decreased abundance in the KOC region in the 1990s are partly attributed to changes in recruitment and availability to the fishing fleets under the warm regime in the spawning and nursery grounds in the East China Sea in association with the quasi-steady state of mild winter monsoon in the 1990s. The fluctuations in chub mackerel and jack mackerel abundance are under the environment-dependant growth form, although the tropicalization was identified in the TWC region. The density-dependant growth form was found in Japanese sardine populations, but no tropicalization by fishing was identified in the long ($10{\sim}15$ year) periods of abundance despite their short ($3{\sim}4$ year) generation time, suggesting that the environment-dependant growth form drove the changes in abundance. Year-to-year and decadal scale variations in abundance and population structure of the Pacific saury responded to climate regime shifts (1976/1977, 1988/1989), suggesting that the fish is a key bio-indicators for changes in the ecosystem.

DENSITY DEPENDENT GRWOTH AND MORTALITY OF MANILA CLAM Ruditapes philippinarum REARED IN CAGES IN GOMSO-BAY, KOREA

  • Park, Kyung-Il;Yang, Hyun-Sung;Kang, Do-Hyung;Choi, Kwang-Sik
    • 한국패류학회지
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    • 제26권1호
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    • pp.91-95
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    • 2010
  • Density-dependant growth and mortality rate of Manila clam Ruditapes philippinarum reared in net cages was investigated in Gomso Bay, Korea where unusually high mortality of clams has been reported. For the experiment, four groups of clam cages were set up with a density of $2,000clams/m^2$ (group A), $1,000clams/m^2$ (group B), $500clams/m^2$ (group C) and $100clams/m^2$ (group D). Mortality and growth of clams in each experimental cage was monitored biweekly from May 2001 to September 2001. Highest mortality in group A was observed in late August, while highest mortality of rest groups was observed in early September. In September, the cumulative mortality in group A was 99%, while it was 93.2% in group B, 91.2% in group C and 88% in group D. Shell growth rate of clams in thecages was found to be density dependent; monthly shell length increase was 0.67 mm in group A, 1.33 mm in group B, 1.63 mm in group C and 1.71 mm in group D. Our study indicated that clam growth and mortality in the Bay is density dependent and the growth and survival rate is negatively correlated with the density.

한약재 복합추출물이 모발 성장 및 멜라닌 생성 촉진에 미치는 영향 (Ethanol extract of medicinal herbal mixture accelerates hair growth and melanogenesis in vivo and in vitro)

  • 김지윤;김유진;김문주;김미려
    • 대한본초학회지
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    • 제33권5호
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    • pp.9-18
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    • 2018
  • Objectives : This study was performed to determine the transdermal effects of ethanol extract from medicinal herbal mixture (SHJ) on hair growth in C57BL/6 mice and melanogenesis in melanoma cells. Methods : Mice were divided into 3 experimental groups including vehicle (CON), SHJ extract and 5% minoxidil (MNXD, positive control)-treated group. SHJ was applied topically on the hair-shaved skin of C57BL/6 mice everyday for 15 days. The thickness and density of hair with a folliscope and morphometry of hair follicle with a H&E staining were monitored at last day. Also then, hair growth-associated gene expressions were measured by immunoblot assay. Results : The MNXD or SHJ-treated group promoted on hair growth compared to that of vehicle-treated group (CON). Hair density and thickness of MNXD or SHJ treated-group increased compared to that of vehicle application on the 15 days, respectively. Induction of insulin-like growth factor (IGF)-1 and vascular endothelial growth factor (VEGF) were also accelerated by application of SHJ extract compared to those of CON group. But expression of transforming growth factor (TGF)-${\beta}1$ decreased in SHJ treated-group compared to that of CON group. Furthermore, SHJ extract showed to increase melanin contents in a dose-dependent manner. Tyrosinase activity significantly increased in SHJ-treated group compared with CON group in dose-dependant manner. Conclusions : These results suggest that SHJ can be used as a component of cosmeceuticals for hair care via promoting growth and melanogenesis of hair.

천화분 추출물이 혈관신생 및 암세포성장에 미치는 영향 (Effects of Trichosanthes kirilowii Extract against Angiogenesis and Various Tumor Cells' Growth)

  • 김동우;이종훈;유화승;조정효;이연월;손창규;조종관
    • 대한한방내과학회지
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    • 제29권2호
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    • pp.490-499
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    • 2008
  • Objectives : This study was aimed to elucidate the effects of Trichosanthes kirilowii extract (TKE) on the angiogenesis and growth of tumor cells. Methods : Tube formation assay was performed by using human umbilical vein endothelial cells (HUVEC), and anchorage dependent colony assay was performed by using B16-F10 melanoma, Hep G2 and HT1080, CT-26 and SNU-1 cells. Results : For HUVEC, TKE at a level of more than 100 ${\mu}g/m{\ell}$ suppresses cell growth. For HUVEC at 100 ${\mu}g/m{\ell}$ and greater TKE density, the formation of tubes was suppressed in a dose-dependant manner. TKE controls the colony formations of B16-F10 melanoma cells, CT 26 cells, and Hep G2 cells, and its effect is proportional to density. In HT1080 cells and SNU-1 cells, formation is suppressed regardless of density. Conclusions : From these results, it could be concluded that TKE has significant properties on anti-angiogenesis and growth inhibiting of tumor cells. It is suggested that TKE will be a good candidate for new drugs or therapeutics for anti-angiogenesis.

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Effects of Low Incident Energy Levels of Infrared Laser Irradiation on the Proliferation of Candida Albicans Part I : A Long Term Study according to Pulse Type

  • Sam-Kun Kim;Phil-Yeon Lee;Ki-Suk Kim
    • Journal of Oral Medicine and Pain
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    • 제19권1호
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    • pp.9-15
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    • 1994
  • This experiment was performed to confirm the hypothesis that LLLT had biostimulation effect for all kinds of cells and there would be differences in the growth of cells among different types of pulsed laser. 360 samples were used in this study. The samples were randomly divided in 6 groups according to the pulse type : quasi continuous type (CW), pulse 1(P1), pulse 7(P7), pulse 9(P9), pulse 15(P15) and shame-irradiated control(Co) groups. Energy fluences of all experimental groups, P1, P7, P9, P15 and CW were 2.12, 2.12, 6.37, 57.32 and 31.85 mj/cm2 respectively. All samples were irradiated for every 1 minute at 0, 12, 24, 36, 48 and 60 hours. Ten samples of each group were sacrificed at 0 and every 12 hours and then the optical density of all samples was measured with the spectrophotometer. As a result, some types of pulses showed significant differences among groups. The increase of cells were markedly stimulated with laser irradiation in P7 and P9 groups, while inhibited in CW, P1, and P15 groups compared with control group. It is therefore, suggested that specific laser pulse should be recommanded to have the biostimulation effects on the specific tissue or cells, although the biostimulation effect is does dependant.

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