• Title/Summary/Keyword: Water retention model

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The Effects of Korean Ginseng on Memory Loss in a Rat Models (Scopolamine 유도 치매동물모델에서 고려인삼(백삼, 홍삼 및 흑삼)의 기억력 개선 효과)

  • Kang, Shin-Jyung;Woo, Jeong-Hwa;Kim, Ae-Jung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.8
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    • pp.1190-1196
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    • 2013
  • The purpose of this study was to investigate the mechanism and effects of different types of ginseng on memory improvement in an experimental rat model. In this study, SD rats were induced for memory deficits through scopolamine treatment (1 mg/kg, i.p.) then administrated with ginseng extract for 7 weeks. The rats were divided into five groups: saline (1 mL/kg, NC: negative control), white ginseng (300 mg/kg, WG), red ginseng (300 mg/kg, RG), black ginseng (300 mg/kg, BG), and scopolamine (1 mg/kg, PC: positive control). The step through latency of the BG and RG groups was significantly longer than the PC group in the retention trial of multiple trial passive avoidance test. In the spatial reference memory triads of the Morris water maze test, the latency time of BG and RG was significantly lower than the PC group. In addition, in the prove test, the time spent in the platform quadrant of BG and RG groups were significantly longer than the PC group. Brain choline acetyltransferase (ChAT) activities BG and RG groups significantly increased compared to other groups. On the other hand, the levels of malondialdehyde (MDA) were significantly lower in the BG and RG groups compared to other groups. These result suggested that black ginseng could be useful to enhance learning memory and cognitive function by regulation of cholinergic enzymes.

Longitudinal Pattern of Large Wood Distribution in Mountain Streams (산지계류에 있어서 유목의 종단적 분포특성)

  • Seo, Jung Il;Chun, Kun Woo;Kim, Min Sik;Yeom, Kyu Jin;Lee, Jin Ho;Kimura, Masanobu
    • Journal of Korean Society of Forest Science
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    • v.100 no.1
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    • pp.52-61
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    • 2011
  • Whereas recent researches have elucidated the positive ecological roles of large wood (LW) in fishbearing channels, LW is also recognized as a negative factor of log-laden debris flows and floods in densely populated areas. However in Republic of Korea, no study has investigated longitudinal variations of LW distribution and dynamic along the stream corridor. Hence to elucidate 1) physical factors controlling longitudinal distribution of LW and 2) their effect on variation in LW load amount, we surveyed the amount of LW with respect to channel morphology in a mountain stream, originated from Mt. Ki-ryong in Inje, Gangwondo. Model selection in the Generalized Linear Model procedure revealed that number of boulder (greater than or equal to 1.0 m in diameter), bankfull channel width and their interaction were the best predictors explaining LW load volume per unit channel segment area (unit LW load). In general, boulders scattered within small mountain streams influence LW retention as flow obstructions. However, in this study, we found that the effect of the boulders vary with the channel width; that is, whereas the unit LW load in the segment with narrow channel width increased continuously with increasing boulder number, it in the segment with wide channel width did not depend on the boulder number. This should be because that, in two channels having different widths, the rates of channel widths reduced by boulders are different although boulder numbers are same. Our findings on LW load varying with physical factors (i.e., interaction of boulder number and channel width) along the stream corridor suggest understanding for longitudinal continuum of hydrogeomorphic and ecologic characteristics in stream environments, and these should be carefully applied into the erosion control works for systematic watershed management and subsequent disaster prevention.