• Fisheries and Aquatic Sciences
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• v.10 no.3
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• pp.159-169
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• 2007

The complex 2-dimensional movements of fish during an annual migration circuit were generated and simulated by a chaotic model of fish movement, which was expanded from a small-scale movement model. Fish migration was modeled as a neural network including stimuli, central decision-making, and output responses as variables. The input stimuli included physical stimuli (temperature, salinity, turbidity, flow), biotic factors (prey, predators, life cycle) and landmarks or navigational aids (sun, moon, weather), values of which were all normalized as ratios. By varying the amplitude and period coefficients of the klinokinesis index using chaotic equations, model results (i.e., spatial orientation patterns of migration through time) were represented as fish feeding, spawning, overwintering, and sheltering. Simulations using this model generated 2-dimesional annual movements of sea bream migration in the southern and western seas of the Korean Peninsula. This model of object-oriented and large-scale fish migration produced complicated and sensitive migratory movements by varying both the klinokinesis coefficients (e.g., the amplitude and period of the physiological month) and the angular variables within chaotic equations.

• Biomolecules & Therapeutics
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• v.22 no.1
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• pp.1-9
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• 2014

Vascular endothelial growth factor (VEGF)-VEGF receptor (VEGFR) system has been shown to play central roles not only in physiological angiogenesis, but also in pathological angiogenesis in diseases such as cancer. Based on these findings, a variety of anti-angiogenic drugs, including anti-VEGF antibodies and VEGFR/multi-receptor kinase inhibitors have been developed and approved for the clinical use. While the clinical efficacy of these drugs has been clearly demonstrated in cancer patients, they have not been shown to be effective in curing cancer, suggesting that further improvement in their design is necessary. Abnormal expression of an endogenous VEGF-inhibitor sFlt-1 has been shown to be involved in a variety of diseases, such as preeclampsia and aged macular degeneration. In addition, various factors modulating angiogenic processes have been recently isolated. Given this complexity then, extensive studies on the interrelationship between VEGF signals and other angiogenesis-regulatory systems will be important for developing future strategies to suppress diseases with an angiogenic component.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.111-111
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• 2001

The relationship between selenium and signal molecules is not well elucidated yet. It was found that physiological concentration of selenite, less than 3 $\mu$M, reduced ASKl activity and induced of PI3-Kinase/Akt pathways in HT1080 cells. Duration of these signal molecules by selenite was much longer than that by growth factors and other stresses. The longer duration time of these signal molecules may be important to maintain normal functions against stresses.(omitted)

• Journal of Korean Physical Therapy Science
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• v.2 no.4
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• pp.793-805
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• 1995

The purposes of this review are to know the characteristics and physical changes of elderly person, and to give the information about elderly person when the geriatric physical therapy will be needed in Korea. Current literature on physiological changes that occur in humans owing to aging is reviewed. The musculoskeletal, cardiopulmonary, neurological, perceptual, gastrointestinal, endocrine and immunological systems are discussed. Also, The cognition, personality, and role changes are discussed. We are discussed the changes of aging; biological theory, psychosocial theory and environmental theory. The effects of disuse and of exercise are reviewed. Implications for geriatric physical therapy are suggested.

• Applied Biological Chemistry
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• v.14 no.1
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• pp.103-107
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• 1971

The hypothesis that the grain having the same specific gravity has the same content in some chemical constituents as a genetic constant of a variety without being affected by the environmental conditions which affect only the percent distribution of grain in specific gravity was tested on nitrogen. Also the applicability of hypothesis on phosphorus, potassium, calcium and physiological significance of hypothesis were discussed.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.2
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• pp.100-104
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• 2002

Serratia marcescens biovar A2/A6, isolated from an Indonesian freshwater source, was identified based on extensive morphological, biochemical and genetic characterization. Formation of pigment was found to be strongly influenced by environmental conditions. Placket-Burman design was used to analyze the effect of carbon and nitrogen sources. Based on results of physiological and biochemical studies, the optimum conditions for growth and pigment formation were incubation 30$^{\circ}C$ in a neutral to slightly alkaline medium containing lactic acid and beef extract.

• Safety and Health at Work
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• v.9 no.2
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• pp.236-238
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• 2018

Sleep deprivation may cause accidents, and it has deteriorating effects on health. A measurement of postural steadiness by a portable and affordable Nintendo Wii Fit balance board can be used to quantify a person's alertness. At work, people are under the influence of their environment-often other peopl-dthat may affect their alertness. This work investigates whether sleep deprivation among people is "contagious," as quantified by sway measures. We measured 21 volunteers' postural steadiness while alert and sleep deprived. During the measurements, a screen placed in front of the participants showed a footage of either alert or sleep-deprived faces. We found a significant difference between the day time and night time steadiness, but found no effect resulting from watching footage of sleep-deprived people. This finding shows that a posturographic sleepiness tester quantifies physiological sleep deprivation, and is insensitive to the influence of social factors.

• Korean Journal of Plant Resources
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• v.11 no.2
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• pp.152-156
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• 1998

This experiment was conducted to investigated the characteristics of grain appearance, chemical components. gelatinization, and palatability of cooked rice on each rachis branches as harvested from the transplanting plot of May 20 and June 5 in each two varieties of early-maturing and late-maturing types. In evaluation of rachis branches, the percentage of ripended grain and 1,000 grain weight were found to be high and heavy at upper part of panicle. The factors influencing palatability such as maximum viscosity and breakdown as gelatinization characteristics, and hardness, apringiness, cohesiveness and chewiness as texture characteristics of cooked rice were found to be high at upper part of panicle , indicating the parlability was favored more at upper part than at lower part of panicle due to the genetics and physiological metabolism of rice plants.

• Molecules and Cells
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• v.20 no.2
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• pp.271-279
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• 2005

Although macrophages are an important first line of cellular defense, they are unable to effectively kill phagocytosed C. albicans. To determine the physiological basis of this inability, we investigated the alterations of macrophage proteins caused by C. albicans infection. Since the formation of C. albicans hyphae caused cell death, proteins were prepared 3 h after infection and examined by two-dimensional gel electrophoresis (2-DE). The most prominent changes were in glycolytic enzymes, which could have caused energy depletion of the infected cells. Also changed were proteins involved in maintenance of cellular integrity and NO production. Treatment of the macrophages with either cytochalasin D or taxol did not alter their inability to kill C. albicans. Our results indicate that multiple factors contribute to cell death as the pathogenic form of C. albicans becomes fully active inside macrophage cells.

• Korean Journal of Microbiology
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• v.26 no.3
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• pp.256-261
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• 1988

Samples from Naktong Estuary had been taken for the characterization of heterotrophic bacterial communities and of the effects of environmental factors on their distribution in estuarine ecosystem. Bacterial communities isolated from seawater region were composed of more euryhalone groups than those from freshwater region, and the bacterial communities of summer were composed of more eurythermal groups than those of winter. Bacterial commnities became more diverse by the input of allochthonous bacteria from terrestrial and freshwater ecosystem, but less diverse by worse environmental conditions such as nutrient load, high salinity, low temperature, and so on.