• 제목/요약/키워드: early stages

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Phosphorylcholine이 보리 엽록체의 광인산화활성에 미치는 저해효과에 대하여 (Inhibitory Effect of Phosphorylcholine on Photophosphorylation of Isolated Chloroplasts from Barley)

  • 유경희
    • Journal of Plant Biology
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    • 제29권3호
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    • pp.157-165
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    • 1986
  • The onset of photophosphorylation at the various stages of greening showed different patterns with varying concentrations of Pi. With further greening, ATP formation occurred at the lower concentration of Pi (48 hrs; 0.05 mM). At early stages of greening, more Pi was required for photophosphorylation (6 hrs; 5.0 mM). The addition of cell-free extracts of etiolated barley seedlings resulted in the competitive inhibition of photophophorylation. The apparent inhibition by cell-free extracts were gradually decreased during greening of etiolated barley seedlings. We found that the inhibitors of photophosphorylation in cell-free extracts were some organic phosphates and most of them was P-choline. P-choline inhibited photophosphorylation competitively with Pi and its content was decreased considerably in greening. It is likely that P-choline partly delay the photophorylation in early stages of greening.

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Cleistocalyx nervosum Extract Ameliorates Chemical-Induced Oxidative Stress in Early Stages of Rat Hepatocarcinogenesis

  • Taya, Sirinya;Punvittayagul, Charatda;Inboot, Wanida;Fukushima, Shoji;Wongpoomchai, Rawiwan
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권6호
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    • pp.2825-2830
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    • 2014
  • Purpose: To study the effect of Cleistocalyx nervosum extract (CE) on diethylnitrosamine (DEN) and phenobarbital (PB) induced oxidative stress in early stages of rat hepatocarcinogenesis. Materials and Methods: Male Wistar rats were divided into 4 groups, with Group 1 as a negative control and Group 2 was a positive control receiving DEN injections once a week and PB in drinking water for 6 weeks. Two weeks before DEN initiation and PB treatment, Groups 3 and 4, were fed with 500 and 1000 mg/kg of CEs, respectively, for 8 weeks. Results: A number of GST-P-positive foci, preneoplastic lesions, in the liver were markedly increased in carcinogen administered rats, but was comparatively decreased in rats treated with 1000 mg/kg of CE. The CE reduced malondialdehyde in serum and in the livers of rats treated with DEN and PB. Moreover, CE significantly increased the activities of glutathione peroxidase and catalase in rat liver. Conclusions: CE appeared to exert its chemopreventive effects by modulating antioxidant status during DEN and PB induced early stages of hepatocarcinogenesis in rats.

Effects of abiotic stressors on kelp early life-history stages

  • Lind, Alyssa C.;Konar, Brenda
    • ALGAE
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    • 제32권3호
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    • pp.223-233
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    • 2017
  • Kelp forests and the many vital ecosystem services they provide are threatened as the severity of climate change and other anthropogenic stressors continues to mount. Particularly in the North Pacific, sea surface temperature is warming and glacial melt is decreasing salinity. This study explored the resiliency of early life-history stages of these foundation species through a factorial laboratory experiment. The effects of rising sea surface temperature under low salinity conditions on kelp spore settlement and initial gametophyte growth in Eualaria fistulosa, Nereocystis luetkeana, and Saccharina latissima were investigated. Decreased settlement and growth were observed in these species at elevated temperatures and at low salinity. Eualaria fistulosa spores and gametophytes were the most negatively impacted, compared to the more widely distributed N. luetkeana and S. latissima. These results suggest that N. luetkeana and S. latissima could potentially outperform E. fistulosa under projected conditions. However, despite decreased performance among all species, our findings indicate that these species are largely resilient to temperature changes when exposed to a low salinity, even when the temperature changes are immediate and extreme. By exploring how early life-history stages of several key kelp species are impacted by dual stressors, this research enhances our understanding of how kelp forests will respond to projected and extreme changes in temperature when already stressed by low salinity.

돼지 단위발생란의 체외발육시 6탄당의 영향 (Effects of Hexoses on In Vitro Development of Parthenogenetic Embryos in the Pigs)

  • 윤선영;김정익;정희태;양부근;박춘근
    • 한국수정란이식학회지
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    • 제20권2호
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    • pp.113-121
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    • 2005
  • This study was conducted to investigate the effects of different hexoses (glucose, mannose, galactose and fructose) on in vitro development of parthenogenetic embryos in the pigs. When the parthnogenetic embryos were cultured in medium with concentrations of 5mM glucose or 1mM galactose, the rates of embyos developed to morula and blastocyst stages were significantly higher than those in another culture conditions (P<0.05). However, high concentration of galactose inhibited development to morula and blastocyst stages. Addition of hexoses at early stage of porcine parthenogenetic embryos were effective for in vitro development. Especially, the embryos cultured in medium with glucose at early stage were effective for development to 2-cell $(72\%)$ and blastocyst $(19\%)$ stages compared with embryo cultured without glucose. From the present results, it is suggested that development of porcine parthenogenetic embryos can improve in medium with 5mM glucose. The concentration of 1mM galactose was also effective for development of porcine parthenogenetic embryos. It also show that parthenogenetic embryos cultured with glucose at early stage can improve in vitro development.

BIM을 이용한 건축물 초기 디자인 단계에서 초고층 업무용 건물의 최적 에너지 형태개발 (Development of Energy Optimized Geometry Using BIM for Super Tall Office Building in Early Design Stages)

  • 류한수;김인한;추승연
    • 한국CDE학회논문집
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    • 제16권2호
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    • pp.83-91
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    • 2011
  • There are many researches to make low-energy building. Lots of them focus on facility systems and insulation performance of building materials. However, not only systematic solutions but also approaches in early design stages are important to reduce energy consumption. Using BIM(Building Information Modelling) is considered as an effective and efficient way to simulate building energy and decide alternatives than traditional energy simulation because BIM based energy simulation makes to reduce much time for energy modeling. This study focuses on development of optimized geometry for super tall office buildings in Seoul, Korea. Specifically, length to width ratio and building orientation are main topics of this study because these two topics are the most basic and preceding factors deciding mass design. In this study, Revit MEP 2011 and Ecotect Analysis 2011 are used to make case models and calculate energy load in early design stages. Energy properties of material abide by Korean Standards for Energy Conservation in Building, Korean Guideline for Energy Conservation in Public Office and ASHRAE Standard in USA. This study presents best length to width ratio of plan and optimized orientation by evaluating the case models. Furthermore, this study suggests what should be considered for each case to decrease energy load.

A STUDY ON THE DEVELOPMENT OF A COST MODEL BASED ON THE OWNER'S DECISION MAKING AT THE EARLY STAGES OF A CONSTRUCTION PROJECT

  • Choong-Wan Koo;Sang H. Park;Joon-oh Seo;TaeHoon Hong;ChangTaek Hyun
    • 국제학술발표논문집
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    • The 3th International Conference on Construction Engineering and Project Management
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    • pp.676-684
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    • 2009
  • Decision making at the early stages of a construction project has a significant impact on the project, and various scenarios created based on the owner's requirements should be considered for the decision making. At the early stages of a construction project, the information regarding the project is usually limited and uncertain. As such, it is difficult to plan and manage the project (especially cost planning). Thus, in this study, a cost model that could be varied according to the owner's requirements was developed. The cost model that was developed in this study is based on the case-based reasoning (CBR) methodology. The model suggests cost estimation with the most similar historical case as a basis for the estimation. In this study, the optimization process was also conducted, using genetic algorithms that reflect the changes in the number of project characteristics and in the database in the model according to the owner's decision making. Two optimization parameters were established: (1) the minimum criteria for scoring attribute similarity (MCAS); and (2) the range of attribute weights (RAW). The cost model proposed in this study can help building owners and managers estimate the project budget at the business planning stage.

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Effects of salinity and irradiance on early developmental stages of Grateloupia turuturu (Halymeniaceae, Rhodophyta) tetrasporophytes

  • Jae Woo Jung;Qikun Xing;Ji-Sook Park;Charles Yarish;Jang K. Kim
    • ALGAE
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    • 제38권2호
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    • pp.151-157
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    • 2023
  • Grateloupia turuturu is a red alga with a flat but firm slippery thallus. Throughout its lifetime, this alga experiences a wide range of environmental stresses in the intertidal rocky shores. The aim of this study is to investigate the effect of salinity and irradiance on the early developmental stages of G. turuturu tetrasporophytes. The released carpospores were cultivated at different salinities (S = 15, 25, and 35) and irradiances (50, 100, and 200 μmol photons m-2 s-1). Germination of carpospores and development of juvenile tetrasporophytes were observed every 5 days and recorded by a digital camera. Discoid crusts were formed at all conditions within 5 days. The discoid crusts at 200 μmol photons m-2 s-1 died within 20 days regardless the salinity. The discoid crusts at S = 35 also died at all irradiance conditions within 25 days. Except for those at S = 35 and 200 μmol photons m-2 s-1, the discoid crusts reached about 8,000-9,000 ㎛2 by day 20. Regardless of irradiance, the upright thalli formation rate from discoid crusts was 85 and 10% at S = 15 and S = 25, respectively. These results suggest that salinity and irradiance are important factors influencing early developmental stages of G. turuturu.

Early Zoeas of Two Snapping Shrimps Alpheus digitalis De Haan, 1850 and Alpheus japonicus Miers, 1879 (Decapoda, Caridea, Alpheidae) with Notes on the Larval Characters of the Alpheidae

  • Yang, Hoi-Jeong;Kim, Chang-Hyun
    • Animal cells and systems
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    • 제6권2호
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    • pp.95-105
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    • 2002
  • Early zoeal stages of two snapping shrimps Alpheus digitalis De Haan, 1850 and Alpheus japonicus Miers, 1879 are described and illustrated in detail for the first time based on the laboratory-reared materials. The first zoeas of Alpheus are more related to those of Vexillipar than to Athanas, Automate, and Synalpheus by having rostrum absent, the tip of the endopod of the antenna with a long plumose seta as well as a spine, the endopod of the maxilla with a basal and two terminal setae, the exopod of the maxilla shorter than the endopod, and the endopod of the second maxilliped with a seta on the proximal segment. A list of larval descriptions and described stages of the Alpheidae reported from Indo-West Pacific waters are included.

An FCA-mediated epigenetic route towards thermal adaptation of autotrophic development in plants

  • Lee, Hyo-Jun;Ha, Jun-Ho;Park, Chung-Mo
    • BMB Reports
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    • 제50권7호
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    • pp.343-344
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    • 2017
  • Plants are able to recognize even small changes in surrounding temperatures to optimize their growth and development. At warm temperatures, plants exhibit diverse architectural adjustments, including hypocotyl and petiole elongation, leaf hyponasty, and reduced stomatal density. However, it was previously unknown how such warm temperatures affected the early stages of seedling development. In our recent study, we demonstrated that the RNA-binding protein, FCA, is critical for sustaining chlorophyll biosynthesis during early seedling development, which is a prerequisite for autotrophic transition at warm temperatures. FCA plays a dual role in this thermal response. It inhibits the rapid degradation of protochlorophyllide oxidoreductases (PORs) that mediate chlorophyll biosynthesis. In addition, it induces the expression of POR genes at the chromatin level, which contributes to maintaining functional enzyme levels. Our findings provide molecular basis for the thermal adaptation of chlorophyll biosynthesis during the early stages of seedling development in nature.

Changes in Plasminogen Activity in Uterus Tissue during the Estrous Cycle in the Pigs

  • Kim, Kang-Hyun;Lee, Yong-Seung;Gu, Ha-Na;Yang, Boo-Keun;Cheong, Hee-Tae;Park, Choon-Keun
    • Reproductive and Developmental Biology
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    • 제35권4호
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    • pp.463-468
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    • 2011
  • This study investigated the changes of plasminogen activators (PAs) activity, expression and localization of tissue plasminogen activator (tPA) and urokinase plasminogen activator (uPA) during the estrous cycle in pigs. Estrous cycle was sorted into three group by pre-ovulation (Pre-Ov), post-ovulation (Post-Ov) and early to mid-luteal stages (Early to mid-L). Analysis for immunohistochemistry was confirmed by location of tPA and uPA. Porcine uterus tissue was cut into $1{\times}1$ cm squares, and were incubated in DMEM/F-12 medium for 1 h at $38^{\circ}C$, 5% $CO_2$ for measurement of PA activity. Western blotting was implemented for measurement of PA quantity. In results, the blood vessels and secretory glands were increased in Post-Ov stage than Pre-Ov and Early to mid-L stages. The tPA and uPA was located mainly within lumen of blood vessels and secretory glands. The PA activity in Post-Ov ($0.99{\pm}0.03$) stage were significantly (p<0.01) higher than Pre-Ov stage ($0.51{\pm}0.03$) and Early to mid-L stage ($0.21{\pm}0.04$). Expression of PAs were significantly (p<0.05) higher in Early to mid-L stage than other stages. These results indicate that PAs activity and expression may change in uterus tissue during the estrous cycle in pigs.