• Title/Summary/Keyword: starvation

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Effect of Feeding and Starvation on Growth and Phenotypic Trait in Olive Flounder, Paralichthys olivaceus (Temminck et Schlegel) (넙치의 사료공급과 절식시 성장과 표현형질 특징)

  • Park In-Seok;Woo Seon-Rang;Kim Eun-Mi;Cho Sung-Hwoan
    • Journal of Aquaculture
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    • v.19 no.3
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    • pp.183-187
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    • 2006
  • A 12-week experiment was conducted to determine the effect of feeding and starvation on survival, growth and the phenotypic trait in olive flounder, Paralichthys olivaceus. Survival and growth of the starved fish group was significantly lower than those of the fed fish group throughout the experiment. Starvation resulted in a retardation in growth, which provided the examples of the reduction in final body weight, growth rate, specific growth rate and condition factor whereas the fed fish group grew well and maintained in good condition. The starved fish group had lower gutted body weight, but similar viscera index and dressing percentage compared to those of the fed fish group. These results suggested that the phenotypic trait used fur starvation and feeding in this study appeared to be an useful index of the nutritional status in olive flounder.

The Schizosaccharomyces pombe Gene Encoding ${gamma}-Glutamyl$ Transpeptidase I Is Regulated by Non-fermentable Carbon Sources and Nitrogen Starvation

  • Kim, Hong-Gyun;Park, Hey-Jung;Kang, Hyun-Jung;Lim, Hye-Won;Kim, Kyung-Hoon;Park, Eun-Hee;Ahn, Ki-Sup;Lim, Chang-Jin
    • Journal of Microbiology
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    • v.43 no.1
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    • pp.44-48
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    • 2005
  • In our previous study, the first structural gene (GGTI) encoding ${\gamma}-glutamyl$ transpeptidase was cloned and characterized from the fission yeast Schizosaccharomyces pombe, and its transcription, using the GGTI-lacZ fusion gene, containing the 1,085 bp upstream region from the translational initiation point, was found to be enhanced by sodium nitroprusside and L-buthionine-(S,R)-sulfoximine (BSO). In the present work, regulation of the GGTI gene was further elucidated. Non-fermentable carbon sources, such as acetate and ethanol, markedly enhanced the synthesis of ${beta}-galactosidase$ from the GGTI-lacZ fusion gene. However, its induction by non-fermentable carbon sources appeared to be independent of the presence of the Pap1 protein. Nitrogen starvation also gave rise to induction of GGTI gene expression in a Pap1-independent manner. The three additional fusion plasmids, carrying 754, 421 and 156 bp regions, were constructed. The sequence responsible for the induction by non-fermentable carbon sources and nitrogen starvation was identified to exist within a -421 bp region of the GGTI gene. Taken together, the S. pombe GGTI gene is regulated by non-fermentable carbon sources and nitrogen starvation.

Analysis of Ring Pack Lubrication (다중 피스톤 링계의 피스톤 링 윤활 해석)

  • 이재선;한동철
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1999.06a
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    • pp.232-239
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    • 1999
  • Generally quantity of supply oil for piston ring lubrication in an internal combustion engine may be insufficient to fill the entire volume formed in the clearance between piston ring and cylinder liner. Thus oil starvation condition should be considered for the analysis of piston ring lubrication. In order to reasonably estimate amount of oil left on the cylinder liner, adequate boundary condition should be adapted for the analysis of ring pack lubrication. In this analysis of ring pack lubrication of an internal combustion engine, oil starvation and open-end boundary conditions are considered at inlet and outlet of piston rings. It is revealed that piston rings are operated under oil starvation in most operating cycle and the result with these conditions are quite different from that with fully-flooded assumption.

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Analysis of Ring Pack Lubrication

  • Lee, Jae-Seon;Han, Dong-Chul
    • Journal of Mechanical Science and Technology
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    • v.14 no.9
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    • pp.928-934
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    • 2000
  • This paper describes a method developed for the simulation of ring pack lubrication characteristic in an internal combustion engine. In general, the quantity of oil supply for piston ring lubrication may be insufficient in filling the entire volume formed at the interference between the piston ring and the cylinder liner. Thus the oil starvation condition should be considered in analyzing piston ring lubrication. In order to reasonably estimate the amount of oil left over on the cylinder liner, the flow rate at the posterior portion of the interface should be calculated with an adequate boundary condition that confirms flow continuity condition. In this analysis, oil starvation and open-end boundary conditions are considered at the inlet and outlet of the piston rings. The lubrication characteristic of each piston ring is obtained by an iterative method with sequential steps. It is revealed that piston rings are operated under oil starvation in most operating cycles and the result under these conditions are quite different from that with the fully-flooded assumption.

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Analysis of Ring Pack Lubrication Considering Oil Transport (오일 이송을 고려한 다중 피스톤 링계의 피스톤 링 윤활 해석)

  • 이재선;한동철
    • Tribology and Lubricants
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    • v.15 no.3
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    • pp.233-239
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    • 1999
  • Generally quantity of supply oil for piston ring lubrication in an internal combustion engine may be insufficient to fill the entire volume formed in the clearance between piston ring and cylinder liner. Thus oil starvation condition should be considered for the analysis of piston ring lubrication. In order to reasonably estimate amount of oil left on the cylinder liner, adequate boundary condition should be adapted for the analysis of ring pack lubrication. In this analysis of ring pack lubrication of an internal combustion engine, oil starvation and open-end boundary conditions are considered at inlet and outlet of piston rings. It is revealed that piston rings are operated under oil starvation in most operating cycle and the result with these conditions are quite different from that with fully-flooded assumption.

A pheromone mutant of Schizosaccharomyces pombe displays nucleolar fragmentation

  • Jun, Jai-Hyun;Kim, Dae-Myung
    • BMB Reports
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    • v.41 no.3
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    • pp.248-253
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    • 2008
  • Stresses and nutritional starvation are two main external signals for the induction of sex pheromones in the fission yeast Schizosaccharomyces pombe. In an attempt to identify the components involved in transduction of starvation signals, we screened 135 temperature-sensitive (ts) mutants and isolated 6 mutants that induced the pheromone even in the presence of a nitrogen source. These mutants exhibited two distict induction phenotypes: pheromone induction at restrictive but not at permissive temperatures; and pheromone induction at both permissive and restrictive temperatures. The times required for the maximum pheromone induction at the restrictive temperature differed slightly in each mutant. In addition to the pheromone induction phenotype, the ts243 and ts304 mutants exhibited cell-division-cycle defects. The ts304 mutant cells showed an abnormal cytoplasmic DAPI staining pattern. The nucleolus of this mutant seemed to be fragmented, a phenomenon which is typically observed in aged yeast cells. The result of our genetic analysis indicated that the pheromone induction mutants belonged to 6 separate complementation groups. We designated these mutants pws1 to pws6.

Characterization of cell wall hydrolases induced by sugar starvation

  • Lee, Eun-Jeong;Koizumi, Nozomu
    • Proceedings of the Korean Society of Plant Biotechnology Conference
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    • 2005.11a
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    • pp.371-374
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    • 2005
  • In our previous work in transcriptional regulation of sugar, expression of genes encoding putative glycosyl hydrolases in Arabidopsis was induced by sugar starvation. They were annotated as b-galactosidase (At5g56870), ${\beta}-xylosidase$ (At5g49360) and ${\beta}-glucosidase$ (At3g60140), which belong to glycosyl hydrolase family that has a catalytic domain of polysaccharides. From the primary structure of deduced amino acid sequence, they were predicted to localize to cell wall. Further investigation of these cell wall hydrolases implicated that cell wall polysaccharides provide metabolizable sugars to nutrient allocation under sugar starvation.

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Analysis for Lubrication of the Piston Ring Considering Oil Transport-Examples (오일이송을 고려한 피스톤 링의 윤활 해석-예제)

  • 이재선;한동철
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1998.10a
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    • pp.358-364
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    • 1998
  • Lubricational characteristics at the interface between the piston ring and the cylinder liner are considered in this paper. To verify that surface shape and operating conditions of the engine can affect the state of lubrication, the changes of the minimum film thickness and friction force are calculated with various conditions. Oil starvation and open-end boundary condition are used to determine computational boundaries as reported on previous paper for lubrication analysis for the piston ring. From this analysis, it can be found that lubricational characteristics are seriously affected by degree of oil starvation, surface shape and operating conditions.

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Effect of Natural Drugs on the Life Support of Starving Rats (기아를 일으킨 흰쥐의 생명연장에 미치는 천연약물의 효과)

  • 박시원;이현아
    • YAKHAK HOEJI
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    • v.39 no.1
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    • pp.14-23
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    • 1995
  • The current study was undertaken to select the crude drug showing life prolonging effect on the starved rats(Sprague-Dawley) and elucidate the reaction mechanism there of. As distilled water extracts prepared from twenty kinds of natural drugs were administered orally to female starved rats, Bupleuri Radix demonstrated the most prominent effect with 34.6% increment in the survival time. To investigate underlying mechanism of life prolonging effect of Bupleuri Radix, the concentrations of adrenocorticosteroids(corticsterone, testosterone and aldosterone) and enzyme activities of superoxide dismutase(SOD), glutamate oxaloacetate transaminase(GOT), glutamate pyrurate transaminase(GPT) were assayed in the serums of rats starved for, 2, 4 and 6 days respectively. The results manifested much elevated values of corticosterone, aldosterone(2 days) and rather decreasing tendency afterwards, specially in the late periods of starvation(6 days). With respect to such a considerable changes according to starvation periods, Bupleur Radix restored these values much near to normal suggesting that Buplerum Radix may play a life prolonging action during starvation probably through reinforcing the homeostatic properties of corticosteroids and some enzyme activities.

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Changes of Morphometric Traits in the Cultured Cyprinid Loach (Misgurnus anguillicaudatus) to Starvation

  • Hur, Jun Wook;Gil, Hyun Woo;Park, In-Seok
    • Ecology and Resilient Infrastructure
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    • v.5 no.4
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    • pp.264-275
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    • 2018
  • The experiment was conducted to investigate the effects of various dietary conditions on external morphometric traits, and sectioned morphometric traits in the cultured cyprinid loach, (Misgurnus anguillicaudatus) for 28 days. For the fed group there was an increase in body weight, standard length, and morphometric dimensions of the head and body cavity regions compared with the starved and initial groups. Sectioned morphometric trait analysis revealed that relative to the starved group, the fed group had greater body circumference, cross-sectional area, and total height (P<0.05). Our results provide data on external and sectioned morphometric changes under starvation conditions, and can be used as a guide to assist in the regulation and scheduling of feeding, and as indices of the nutritional status of cyprinid loach.