• Title/Summary/Keyword: life stages

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Aroclor 1254 May Induce Common DNA Effects in Developing Paralichthys olivaceus Embryos and Larvae

  • Min, Eun Young;Kang, Ju Chan
    • Fisheries and Aquatic Sciences
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    • v.17 no.4
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    • pp.461-469
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    • 2014
  • Polychlorinated biphenyls (PCBs) are persistent pollutants in aquatic environments, often causing the decline or disappearance of wild populations. In this study, we used a random amplified polymorphic DNA (RAPD) assay to evaluate the effects on the genomic DNA of olive flounder embryo and larval stages of exposure to Aroclor 1254 at concentrations of 1, 5, 10, 20, and $40{\mu}g/L$. We compared RAPD fingerprints of exposed and non-exposed samples. Polymorphisms were revealed as the presence and/or absence of DNA fragments between the two samples. A dose-dependent increase in the number of polymorphic bands was observed with Aroclor 1254 treatment. Also, RAPD profiles of animals exposed to Aroclor 1254 exhibited an increase in the frequency values (FV) compared to the control. A phenogram constructed using neighbor-joining method indicated that genomic template stability in developing embryo and larval stages was significantly affected at ${\geq}5{\mu}g/L$. This study suggested that DNA polymorphisms detected by RAPD analysis could be used as an investigative tool for environmental toxicology and as a useful biomarker in early life stages for the detection of potential genotoxicants.

Dietary protein requirement of Pacific white shrimp Litopenaeus vannamei in three different growth stages

  • Lee, Chorong;Lee, Kyeong-Jun
    • Fisheries and Aquatic Sciences
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    • v.21 no.10
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    • pp.30.1-30.6
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    • 2018
  • A study of three feeding trials was conducted to investigate the dietary protein requirements of Pacific white shrimp (Litopenaeus vannamei) at three different growth stages. Six experimental diets were formulated to include increasing protein levels of 25, 30, 35, 40, 45, and 50% (designated as P25, P30, P35, P40, P45, and P50, respectively) for three feeding trials. The three feeding trials were conducted in different-sized shrimp at 0.65 g (trial 1), 4.80 g (trial 2), and 10.5 g (trial 3). Triplicate groups of shrimp were fed one of the experimental diets for 36, 42, and 48 days in trials 1, 2, and 3, respectively. In trial 1, the growth performance was not affected by the dietary protein levels. However, protein efficiency ratio was significantly higher in P30 diet compared to P40, P45, and P50 diets. In trial 2, growth rate was significantly higher in P35 diet than in P25 diet. In trial 3, the lowest growth performance was obtained in P25 diet which significantly differed from that of other experimental diets. Broken line analysis of growth data indicates that the optimal dietary level of crude protein is 34.5, 35.6, and 32.2% for small-, medium-, and large-sized (juvenile, sub-adult, and adult stages) Pacific white shrimp, respectively.

Lmbr1 Expression in Early Embryo Development Stages in White Leghorn and Chinese Silky

  • Zhang, Ying;Xu, Weizhuo;Li, Ning
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.1
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    • pp.7-12
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    • 2009
  • Lmbr1 is regarded as a key gene that controls the digital model formation in early developmental stages of the chicken. However, there are few reports of lmbr1 expression levels and tendencies in 4-toe and 5-toe chicken species. Therefore, the objective of this study was to compare the lmbr1 expression in White Leghorn (4-toe) and Chinese Silky (5-toe). Firstly, total RNA was extracted from 14 different embryonic development stages (HH3 to HH31) in White Leghorn and Chinese Silky. Secondly, dramatic gene expression changes of lmbr1 were monitored by RT-PCR, which indicated a general up-down-up tendency with subtle differences between these two species. Moreover, Q-PCR reactions were performed to quantitate the expression level of lmbr1 in the 14 selected developmental stages. These data demonstrated a first lmbr1 expression peak of 18.68 and 15.32, a lmbr1 expression trough of 6.61 and 1.80, and a second lmbr1 expression peak of 22.33 and 12.48 in White Leghorn and Chinese Silky, respectively. Finally, embryonic in situ hybridization analysis identified that lmbr1 expressed in the ectoderm in HH21, HH23 and HH24 developmental stages in both species.

A Study on Moment of Truth of Household Telecommunication and Distribution Services in Korea

  • Choi, Hwa-Yeol;Lee, Hyuk-Jin
    • Journal of Distribution Science
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    • v.16 no.6
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    • pp.37-53
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    • 2018
  • Purpose - There have been not enough studies on the ways customer Moment of Truth(MOT) activities are structured along with consumption chain and their influences as well as the relative influences of service quality at Moment of Truth on customer performance. Therefore, customer service needs needed at Moment of Truth may differ depending on whether these distribution services are at introduction-growth stages or maturity-decline stage already, but there is no study which illustrates this. Research design, data, and methodology - This study selects VoIP and IPTV as the household telecommunication and distribution services at introduction-growth stages as well as high speed internet and wire telephone as those at maturity-decline stages. Then it identifies which experiences that customers have at Moment of Truth by each service as well as the influences related to what the customers consider as important. Results - As the result of demonstration with the target of 858 respondents, customers' experiences and requests differ at Moment of Truth. For service quality, what takes the positive roles in customer performance includes corporeality and certainty for the services at introduction-growth stages as well as reliability, sympathy, and mutuality for those at maturity-decline stages. Conclusions - Implications of these results as well as further directions for study are suggested.

A Study of the Formation Process of the Fabric Drapes

  • Mizutani, Chiyomi;Baba, Takeichirou;Amano, Toshihiko
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.10a
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    • pp.111-111
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    • 2003
  • In our experiments using a new apparatus, the drape formation process was found to consist of three stages, seeds generation, their development and the final stabilizing stages. A new parameter R evaluating the shape of the drape was defined in terms of the vertical projection of the drape. Both drape coefficient and R-parameter are expected to be useful for analyzing the formation process of the fabric drape quantitatively.

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Screening the level of cyanogenic glucosides (dhurrin) in sorghum accessions using HPLC analysis

  • Choi, Sang Chul;Chung, Yong Suk;Lee, Yun Gyeong;Park, Yun Ji;Kim, Changsoo
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.104-104
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    • 2017
  • Sorghum (Sorghum bicolor (L.) Moench.) is one of the most important crops for human and animal nutrition. Nonetheless, sorghum has a cyanogenic glucoside compound which can be degraded into hydrogen cyanide, toxic to humans and animals even with tiny amount. In consequence, breeding materials with a low cyanide level has been a top priority in sorghum breeding programs. To fulfill our long-term goal, we are screening sorghum accessions with low cyanide level, which would be an important breeding material for food safety. We collected seeds of various sorghum accessions and analyzed relevant metabolites to find useful breeding materials of sorghum accessions containing low cyanide. Fourteen wild relatives were obtained from the University of Georgia in US, a reference accession BTx623, and three local varieties from National Agrobiodiversity Center of Rural Development Administration in Korea, and one wild species from the Wild Plant Resources Seed Bank of Korea University in Korea. Sorghum plants were grown in plastic greenhouse under natural conditions. After growing, leaf samples were harvested at different developmental stages: seedling phase, vegetative phase (right before flowering), and reproductive phase (ripening). Using collected samples, quantification analysis were performed by an HPLC system for three metabolites (dhurrin, 4-hydroxybenzaldehyde, and 4-hydroxyphenylacetic acid) in sorghum plants. Prior to metabolome analysis, specific experimental condition for HPLC system was set to be able to separate three metabolites simultaneously. Under this condition, these metabolites were quantified in each accession by HPLC system. We observed that the metabolite contents were changed differently by developmental stages and accessions. We clustered these results into five groups as patterns of their contents by developmental stages. Most of accessions showed that 4-hydroxybenzaldehyde content was very high at seedling stage and decreased rapidly at vegetative phase. Interestingly, the patterns of dhurrin content were very different among clusters. However, 4-hydroxyphenylacetic acid content was maintained at low levels by developmental stages in most accessions. The results would demonstrate how dhurrin and alternative degradation pathways are differentiated in each accession.

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Advertisement Design Strategy of According to The Brand Life Cycle (브랜드 수명주기에 따른 광고디자인 전략에 관한 연구)

  • Kim, Eun-Young;Lee, Jin-Ryeol
    • Archives of design research
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    • v.18 no.3 s.61
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    • pp.139-148
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    • 2005
  • Generally, the brand has its life cycle as the product has. This life cycle is classified into the stages; introduction, growth, maturity and decline. Since the brand is little different from that of the product's, we can find some differences when it applies to the brand. The most effective method to perceive the brand to the consumers is advertisement, therefore in the advertisement design, it is important to figure out the current stage in the brand life cycle and use the most ideal design strategy in that stage. This study suggests the concept of the brand life cycle and the most effective strategy in each stages of the advertisement design. In the stage of the brand introduction, we apply the 'What is it? Strategy' which introduces the brand itself. In the stage of the growth, 'How does it Differ from? Strategy' is suggested as the advertisement strategy emphasizing the positioning which shows its differential competitive advantages among brands because in this stage there are many competitive brands in the market. In the stage of the maturity, we focus on the 'What does it Convey of? Strategy' stressing on the delivery of brand's value to consumers as consumers they purchase the brand. Finally in the stage of the decline, 'What does it Stand for? Strategy' is suggested in order to emphasize the generation of brand's symbolical meaning rather than to emphasize it's attributes or benefits. Therefore the advertisement design needs the contingent ideal design strategy according to the stages of brand life cycle and the effective brand management through it.

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Expression patterns of PRDM10 during mouse embryonic development

  • Park, Jin-Ah;Kim, Keun-Cheol
    • BMB Reports
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    • v.43 no.1
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    • pp.29-33
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    • 2010
  • It is well known that PR/SET family members participate in transcriptional regulation via chromatin remodeling. PRDM10 might play an essential role in gene expression, but no such evidence has been observed so far. To assess PRDM10 expression at various stages of mouse development, we performed immunohistochemistry using available PRDM10 antibody. Embryos were obtained from three distinct developmental stages. At E8.5, PRDM10 expression was concentrated in the mesodermal and neural crest populations. As embryogenesis proceeded further to E13.5, PRMD10 expression was mainly in mesoderm-derived tissues such as somites and neural crest-derived populations such as the facial skeleton. This expression pattern was consistently maintained to the fetal growth period E16.5 and adult mouse, suggesting that PRDM10 may function in tissue differentiation. Our study revealed that PRDM10 might be a transcriptional regulator for normal tissue differentiation during mouse embryonic development.

Physicochemical Characteristics and Antioxidative Effects of Korean Figs(Ficus carica L.) (국내산 무화과의 이화학적 특성 및 항산화 활성)

  • 정미란;김병숙;이영은
    • Journal of the East Asian Society of Dietary Life
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    • v.12 no.6
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    • pp.566-573
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    • 2002
  • In order to obtain the basic data fer the processing adaptability of Korean figs(Ficus carica L.), physicochemical analyses were carried out with Korean common type figs in the different ripening stages. Moisture contents decreased, but the contents of protein, fat carbohydrate and soluble solids increased according to the ripening of fruits. K was detected as the most abundant one of all the minerals and Ca, Mg, Na, Fe, Mn, Zn and Cu were the next in order. The mineral contents decreased slightly with ripening. Especially, Ca, Mg, U, Fe and Zn were higher in the unripened H stage figs. The antioxidative activity was assayed with water and methanol extracts from ripened figs by the DPPH radical scavenging ability. The antioxidative activities of Korean figs were relatively high and increased in a dose dependent manner. The methanol extract showed the higher antioxidative activity than the water one. Therefore, the methanol was the better solvent than water for the antioxidative compounds. These results suggested that Korean figs are relatively the good sources of minerals, especially the Ca and the antioxidative compounds.

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The changes in the activities of Cellulase and Xylanase of Aspergillus phoenicis during the life cycle (Aspergillus phoenicis의 生活史를 통한 Cellulase 및 Xylanase의 活性 변화)

  • Oh, Chan-Seok;Lee, Yung-Nok
    • Korean Journal of Microbiology
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    • v.22 no.2
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    • pp.91-96
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    • 1984
  • The changes in the activities of Cellulase and Xylanase of A. phoencis during the life cycle were surveyed by using synchronized culture technique. Avicelase activity of the fungus was reached at peak in the initial hyphal growth stage, but decreased gradually during the conidiophore formation, vesicle-phialide formation, and sporulation stages in decreasing order. CMCase, Salicinase, and Xylanase activities were raised very high in the initial hyphal growth stage, but decreased gradually in conidiophore formation and vesicle-phialide formation stages, and then increased, more or less, in the sporulation stage.

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