• Title/Summary/Keyword: Cluster Reduction

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Modeling the Effect of a Climate Extreme on Maize Production in the USA and Its Related Effects on Food Security in the Developing World (미국 Corn Belt 폭염이 개발도상국의 식량안보에 미치는 영향 평가)

  • Chung, Uran
    • Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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    • 2014.10a
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    • pp.1-24
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    • 2014
  • This study uses geo-spatial crop modeling to quantify the biophysical impact of weather extremes. More specifically, the study analyzes the weather extreme which affected maize production in the USA in 2012; it also estimates the effect of a similar weather extreme in 2050, using future climate scenarios. The secondary impact of the weather extreme on food security in the developing world is also assessed using trend analysis. Many studies have reported on the significant reduction in maize production in the USA due to the extreme weather event (combined heat wave and drought) that occurred in 2012. However, most of these studies focused on yield and did not assess the potential effect of weather extremes on food prices and security. The overall goal of this study was to use geo-spatial crop modeling and trend analysis to quantify the impact of weather extremes on both yield and, followed food security in the developing world. We used historical weather data for severe extreme events that have occurred in the USA. The data were obtained from the National Climatic Data Center (NCDC) of the National Oceanic and Atmospheric Administration (NOAA). In addition we used five climate scenarios: the baseline climate which is typical of the late 20th century (2000s) and four future climate scenarios which involve a combination of two emission scenarios (A1B and B1) and two global circulation models (CSIRO-Mk3.0 and MIROC 3.2). DSSAT 4.5 was combined with GRASS GIS for geo-spatial crop modeling. Simulated maize grain yield across all affected regions in the USA indicates that average grain yield across the USA Corn Belt would decrease by 29% when the weather extremes occur using the baseline climate. If the weather extreme were to occur under the A1B emission scenario in the 2050s, average grain yields would decrease by 38% and 57%, under the CSIRO-Mk3.0 and MIROC 3.2 global climate models, respectively. The weather extremes that occurred in the USA in 2012 resulted in a sharp increase in the world maize price. In addition, it likely played a role in the reduction in world maize consumption and trade in 2012/13, compared to 2011/12. The most vulnerable countries to the weather extremes are poor countries with high maize import dependency ratios including those countries in the Caribbean, northern Africa and western Asia. Other vulnerable countries include low-income countries with low import dependency ratios but which cannot afford highly-priced maize. The study also highlighted the pathways through which a weather extreme would affect food security, were it to occur in 2050 under climate change. Some of the policies which could help vulnerable countries counter the negative effects of weather extremes consist of social protection and safety net programs. Medium- to long-term adaptation strategies include increasing world food reserves to a level where they can be used to cover the production losses brought by weather extremes.

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Lymphocyte Subpopulations and Proliferation of T cells, Phagocytic Activity of Leukocytes on Alcoholics (알코올중독자의 백혈구탐식능, 림프구아형 및 증식능)

  • 김용호;서병배;이정녀;김영훈
    • Biomedical Science Letters
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    • v.2 no.2
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    • pp.167-174
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    • 1996
  • Alcoholics increased susceptibility to microbial infection that is associated with decreased immunity. but there has been little experimental evidence to support alcoholics-induced increase of microbial infection directly in non-specific immunity. Therefore, we were used the method of phagocytic-plaque including all the stimulating factors for the phagocytosis, subtypes of lymphocytes and T-lymphocyte proliferation. The experimental groups were divided into 3 groups: (1) alcoholics who were hospitalized less than 1 week (newly hospitalized alcoholics), (2) alcoholics who were hospitalized more than 2 weeks (old hospitalized alcoholics), (3) healthy blood donors. We have studied 98 alcoholics and 35 healthy blood donors and control groups. A physician has checked the biological markers and diagnosed the body-condition alcoholics. The immunity and non-specific immunity on the alcoholics were analyzed by using the simultest kit and flow cytometry. Proliferation of the lymphocytes was analyzed by the phytohemmagglutinine mitogen. Phagocytosis and migration properties of leukocytes were identified on the layer formed by Staphylococcus aureus Cowan I strain. Biological markers of alcoholics and control groups, by such as blood glucose, ${\gamma}$-glutamyl transpeptidase and mean corpuscular volumes of red blood cells, were determined by biochemical and hematological methods. Compared with control groups, cluster of differentiation (CD)3+, CD8+ and CD19+ in alcoholic were more decreased except CD4+/CD8+ ratio. Proliferation of the T-lymphocytes, phagocytosis and migration properties of the leukocytes in alcoholics were decreased compared with those of control groups. According to the results observed in our experiment, they can be summerized as follows: 1, Cellular, humoral and non-specific immunities, are markedly decreased in alcoholics than those in control groups. 2. It is inferred that Phagocytic plaque formation is a very useful method to evaluate phagocytosis and migration properties of the alcoholic leukocytes 3. It is thought that the subtypes of lymphocytes, especially CD4+/CD8+ ratio, are essential methods to analyzed the alcoholic immunity. 4. Specific and non-specific immunity on the old hospitalized alcoholics was slightly increased, which depends upon the alcoholic medication.

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Suggestion of Similarity-Based Representative Odor for Video Reality (영상실감을 위한 유사성 기반 대표냄새 사용의 제안)

  • Lee, Guk-Hee;Choi, Ji Hoon;Ahn, Chung Hyun;Li, Hyung-Chul O.;Kim, ShinWoo
    • Science of Emotion and Sensibility
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    • v.17 no.1
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    • pp.39-52
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    • 2014
  • Use of vision and audition for video reality has made much advancement. However use of olfaction, which is effective in inducing emotion, has not yet been realized due to technical limitations and lack of basic research. In particular it is difficult to fabricate many odors required for each different video. One way to resolve this is to discover clusters of odors of similar smell and to use representative odor for each cluster. This research explored clusters of odors based on pairwise similarity ratings. 300 diverse odors were first collected and sorted them into 11 categories. We selected 152 odors based on their frequency, preference, and concreteness. Participants rated similarity on 1,018 pairs of odors from selected odors and the results were analyzed using multi-dimensional scaling (MDS). Based on the idea that low odor concreteness would support valid use of representative odor, the MDS results are presented from low to high smell concreteness. First, flowers, plants, fruits, and vegetables was classified under the easy categories to use representative odor due to their low smell concreteness (Figure 1). Second, chemicals, personal cares, physiological odors, and ordinary places was classified under the careful categories of using it due to their intermediate concreteness (Figure 2). Finally, food ingredients, beverages, and foods was classified under the difficult categories to use it because of their high concreteness (Figure 3). The results of this research will contribute to reduction of cost and time in odor production and provision of realistic media service to customers at reasonable price.

Effect of Sand Extraction on Meiobenthic Community of Jangbong-do in the Eastern Yellow Sea of Korea (서해 주문도 연안 사질 조하대에서의 해사채취가 중형저서동물 군집에 미치는 영향 연구)

  • Kang, Teawook;Min, Won-Gi;Hong, Jae-Sang;Kim, Dongsung
    • Korean Journal of Environmental Biology
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    • v.32 no.2
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    • pp.138-152
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    • 2014
  • The objective of the study survey was to determine the effect of marine sand extraction on community composition and rate of recolonization of the meiobenthos following cessation of mining activities. Because of meiobenthic distribution in nature, high abundance, intimate association with sediments, fast reproduction, benthic larva period, sensitivity to pollution and rapid life histories, meiobenthos are widely regarded as ideal organisms to study the potential ecological indicator of natural and anthropogenic stresses. The community structure of meiobenthos was studied at seven stations within sandy tidal and sub tidal zones in Jangbongdo in the Yellow Sea, Korea from Aug. 2006 to Dec. 2007. Meiobenthic samples were collected by three core samples, with a 3.6 cm in diameter, from each sediment sample taken with a Smith-McIntyre Grab. It was found that sand mining often causes complete removal of the sediment and the damage to the habitats of meiobenthos. This study in the effect showed that sand mining resulted in a reduction in total abundance and biomass of meiobenthos in mining area. The finding of this study further showed that initial restoration of abundance and biomass within one year of the cessation of sand mining.

Effects of Salicylic Acid and 1-Methylcyclopropene on Physiological Disorders and Berry Quality in 'Campbell Early' Table Grapes (Salicylic acid 및 1-MCP 처리가 '캠벨얼리' 포도의 생리장해 및 품질에 미치는 영향)

  • Kim, Sung-Joo;Noh, Soo-In;Choi, Cheol;Lim, Byung-Sun;Ahn, Young-Jik;Chun, Jong-Pil
    • Journal of Bio-Environment Control
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    • v.28 no.3
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    • pp.218-224
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    • 2019
  • This study was conducted to compare the effect of salicylic acid (SA), an ethylene biosynthesis inhibitor, and the 1-methylcyclopropene (1-MCP) fumigation, to prevent fruit quality deterioration and physiological disorders during the shelf-life of Korea's leading export grape variety 'Campbell Early'. The berries treated with SA after 1-MCP fumigation (1-MCP+SA) showed a higher firmness value and titratable acidity than single treatment of SA or 1-MCP. The rate of shattered berry was high as 41.7% for 100ppm ethephon spray, 40.8% for $25{\mu}M$ SA, and 38.2% for 1,000ppb 1-MCP, but showing only 18.7% when the SA was applied after 1-MCP fumigation. The ratio of short brushes less than 1mm was largest at 74.3% for ethephon treatment, while 1-MCP+SA treatment was found to have the longest brush length among all treatments, with a 2-4mm ratio of 22.8% and a 4-6mm ratio of 27.9%. The weight of rachis was found to be the lowest at 2.3g in the ethephon treatment, and the reduction of rachis weight loss per cluster by 1-MCP+SA treatment was evident. In addition, 1-MCP+SA treatment were effective in mitigating stem browning and berry decay during the 16-day storage period at $19^{\circ}C$ in this cultivar, so it is believed that they can be used as a practical post-harvest treatment in grape exportation.

Grapevine Growth and Berry Development under the Agrivoltaic Solar Panels in the Vineyards (영농형 태양광 시설 설치에 따른 포도나무 생육 및 과실 특성 변화 비교)

  • Ahn, Soon Young;Lee, Dan Bi;Lee, Hae In;Myint, Zar Le;Min, Sang Yoon;Kim, Bo Myung;Oh, Wook;Jung, Jae Hak;Yun, Hae Keun
    • Journal of Bio-Environment Control
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    • v.31 no.4
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    • pp.356-365
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    • 2022
  • Agrivoltaic systems, also called solar sharing, stated from an idea that utilizes sunlight above the light saturation point of crops for power generation using solar panels. The agrivoltaic systems are expected to reduce the incident solar radiation, the consequent surface cooling effect, and evapotranspiration, and bring additional income to farms through solar power generation by combining crops with solar photovoltaics. In this study, to evaluate if agrivoltaic systems are suitable for viticulture, we investigated the microclimatic change, the growth of vines and the characteristics of grape grown under solar panels set by planting lines compared with ones in open vineyards. There was high reduction of wind speed during over-wintering season, and low soil temperature under solar panel compared to those in the open field. There was not significant difference in total carbohydrates and bud burst in bearing mother branches between plots. Despite high content of chlorophyll in vines grown under panels, there is no significant difference in shoot growth of vines, berry weight, cluster weight, total soluble solid content and acidity of berries, and anthocyanin content of berry skins in harvested grapes in vineyards under panels and open vineyards. It was observed that harvesting season was delayed by 7-10 days due to late skin coloration in grapes grown in vineyards under panels compared to ones grown in open vineyards. The results from this study would be used as data required in development of viticulture system under panel in the future and further study for evaluating the influence of agrivoltaic system on production of crops including grapes.