• Title/Summary/Keyword: physiological adaptation

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Astaxanthin Biosynthesis Enhanced by Reactive Oxygen Species in the Green Alga Haematococcus pluvialis

  • Kobayashi, Makio
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.8 no.6
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    • pp.322-330
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    • 2003
  • The unicellular green alga Haematococcus pluvialis has recently attracted great inter-est due to its large amounts of ketocarotenoid astaxanthin, 3,3'-dihydroxy-${\beta}$,${\beta}$-carotene-4,4'-dione, widely used commercially as a source of pigment for aquaculture. In the life cycle of H. pluvialis, astaxanthin biosynthesis is associated with a remarkable morphological change from green motile vegetative cells into red immotile cyst cells as the resting stage. In recent years we have studied this morphological process from two aspects: defining conditions governing astaxanthin biosynthesis and questioning the possible function of astaxanthin in protecting algal cells against environmental stress. Astaxanthin accumulation in cysts was induced by a variety of environmental conditions of oxidative stress caused by reactive oxygen species, intense light, drought, high salinity, and high temperature. In the adaptation to stress, abscisic acid induced by reactive oxygen species, would function as a hormone in algal morphogenesis from veget ative to cyst cells. Furthermore, measurements of both in vitro and in vivo antioxidative activities of astaxanthin clearly demonstrated that tolerance to excessive reactive oxygen species is greater in astaxanthin-rich cysts than in astaxanthin-poor cysts or astaxanthin-less vegetative cells. Therefore, reactive oxygen species are involved in the regulation of both algal morph O-genesis and carotenogenesis, and the accumulated astaxanthin in cysts can function as a protective agent against oxidative stress damage. In this study, the physiological roles of astaxanthin in stress response and cell protection are reviewed.

Primary Production System in the Southern Waters of the East Sea, Korea III. Vertical Distribution of the Phytoplankton in Relation to Chlorophyll Maximum Layer

  • Shim, Jae-Hyung;Park, Jong-Gyu
    • Journal of the korean society of oceanography
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    • v.31 no.4
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    • pp.196-206
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    • 1996
  • Vertical profiles of the chlorophyll ${\alpha}$, phytoplankton abundance, nutrients and sigma-t were compared with the vertical distribution of phytoplankton species in conjunction with $^{14}$C primary production in the Southern Waters of the East Sea, Korea. In the upper mixed layer the water column was only weakly stratified and ambient nitrogenic nutrient concentrations were markedly depleted. Dissolved silicate seemed to be another limiting nutrient in the surface layer. The occupation of different water depths by several dominant diatom species was well explained by the degree of silicification of each cell and the silicate concentration of ambient seawater. Subsurface chlorophyll maxima were continuously observed in the lower parts of the euphotic layer and the depth coincided with nutricline, supporting our view that chlorophyll maximum was sustained partially by enhancement of in situ growth of phytoplankton and partially by increase of cellular chlorophyll content. The persistence of chlorophyll maximum layer was attributed to the physiological adaptation of the phytoplankters to low light intensities and to the utilization of regenerated nutrients. Integrated water column production of organic matter by photosynthesis appeared to be better related to phytoplankton cell division than to the cell growth in terms of biosynthesis of pigments and other intracellular components.

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Overview on the Sasang Constitutional Abdominal Examination based on Experienced Prescriptions in the Donguisusebowon (동의수세보원(東醫壽世保元) 경험방에 근거한 사상체질별 복진의 문헌연구)

  • Lee, Jae-Chul;Kim, Sang-Hyuk
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.26 no.2
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    • pp.141-146
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    • 2012
  • Researches of Sasang Consitutional Medicine(SCM) have been conducted in many ways, especially for objective diagnosis methods of SCM. Despite of these efforts, relationship between SCM and abdominal examination is rarely known. Therefore 7 books related to abdominal examination and arranged specific abdominal examination descriptions in each books based on Experienced prescriptions(經驗方) of Donguisusebowon(東醫壽世保元) or Longevity and Life Preservation in Eastern Medicine were collected. In result, So-eumin and So-yangin show opposite descriptions to each others in abdominal examination. So-eumin has stuffiness and rigidity below heart, lower abdominal fullness and cramp. In contrast, So-yangin has fullness in the chest and hypochondrium, chest bind, lower abdominal numbness and lower tension. Strong abdominal surface tension could be palpated in Taeum-in's abdominal examination. Advantages of Abdominal Examination are notified recently, thanks to easiness of performing, objectiveness and well-adaptation to Theory of Traditional Eastern Medicine. These advantages could contribute to researching diagnosis of SCM with theory consensus of SCM specialists and practical trials.

Analysis of Experimental Research Trends on Doctoral Dissertations in Nursing (간호학 박사학위논문의 실험연구 경향 분석)

  • Yoon, Heun-Keung;Kim, Hee-Soon;Yun, Hyun-Jung
    • The Journal of Korean Academic Society of Nursing Education
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    • v.17 no.3
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    • pp.464-477
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    • 2011
  • Purposes: The purpose of this study was to identify recent trends of experimental research by analyzing doctoral dissertations in all colleges of nursing in Korea. Methods: The areas of research, the content, methodological and intervention characteristics used in this study were explored in experimental research on doctoral dissertations (n=132) published from 2006 to 2010. Results: In the issues of research, practice/clinical issues were most frequently used. As to outcome measurement, physiological variables increased more than psychological/emotional variables. Most theory applied in the research was taken from other disciplines, and nursing theory was only Roy's adaptation theory. A large majority of the research was quasi-experimental designs and the number of true-experimental designs was very low. In more than half of the dissertations, internal validity was not described, and the described external validity rate was very low. There were more single intervention programs than bundle ones and education/exercise programs were most frequently used as the source of intervention. Conclusion: Doctoral dissertations need to increase and encourage more high quality experimental research to expand nursing knowledge and to develop evidence based nursing practice.

Study in the Local Developing Form of Oriental Medicine Industry (한방산업의 지역개발유형연구)

  • Jung, Do-Ge;Kim, Kwang-Joong
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.19 no.1
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    • pp.19-28
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    • 2005
  • According to each developing type, we study a concept, contents and a consideration about in oriental medicine industry. The divisions of each developing speciality are followings: Urban industry type - The development of urban industry type has difficulties; The lack of technical development and social adaptation, etc. If it overcomes these difficulties, it will be activated in the oriental medicine industry. Rural industry type - The oriental medicine industry of rural type needs the model of rural oriental medicine industry which leads an activity and an independence of the rural region. Within the industrialization of the oriental medicine industry, if rural resource makes a specialized brand, it can have great effects in the future industry. Resort industry type - When The resort type is related the characters of natural circumstances, cultural industry and health management, it has many effects. If we gain the clear direction which is activated the regional specialities, the oriental medicine industry of resort type can estabilishs the high value industry. Event industry type - The event type is a festival, an exhibition, etc. Within this event, the promoter must provide visitors the specialized sights, the food things, the enjoyable things. And using traditional image, we have the regional resource is recognized good things and the nomination of open place can inform.

Influence of preserved brewing yeast strains on fermentation behavior and flocculation capacity

  • Cheong, Chul;Wackerbauer, Karl;Beckmann, Martin;Kang, Soon-Ah
    • Nutrition Research and Practice
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    • v.1 no.4
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    • pp.260-265
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    • 2007
  • Preservation methods on the physiological and brewing technical characters in bottom and top brewing yeast strains were investigated. The preserved yeasts were reactivated after 24 months storage and grown up to stationary phase. The samples of filter paper storage indicated a higher cell growth and viability during propagation than those of nitrogen and lyophilization storage independent on propagation temperature. In addition, the filter paper storage demonstrated a faster absorption of free amino nitrogen and a highest level of higher aliphatic alcohols production during propagation than other preservation methods, which can be attributed to intensive cell growth during propagation. Moreover, the filter paper storage showed a faster accumulation for glycogen and trehalose during propagation, whereas, in particular, lyophilization storage noted a longer adaptation time regarding synthesis of glycogen and trehalose with delayed cell growth. In beer analysis, the filter paper storage formed an increased higher aliphatic alcohols than control. In conclusion, the preservation of filter paper affected positively on yeast growth, viability and beer quality independent on propagation temperature. In addition, in this study, it was obtained that the HICF and Helm-test can be involved as rapid methods for determination of flocculation capacity.

A Study on the Operator Performance According to the Drastic Change of Illumination Level and Lighting Environment of Control Room in Nuclear Power Plants

  • Shin, Kwang Hyeon;Lee, Yong Hee
    • Journal of the Ergonomics Society of Korea
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    • v.32 no.1
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    • pp.37-45
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    • 2013
  • Objective: This study describes the change of operator performance in drastic change of illumination level, and proposes an alternative method to cope with it. Background: The control standard of illumination for nuclear power plants(NPPs) is based on the set of limit criteria for maintaining a specific illumination level. However, there is a possibility to cause human errors according to the psychological and physiological influences to operators in the situation of drastic change of illumination such as SBO(Station Black Out), so a basic study is necessary to review the current approach. Method: We assessed the visual fatigue, subjective work load and task performance according to the three illumination situations(Normal Illumination, Emergency Illumination, and Drastic Change of Illumination). Result: Research finding shows that there are not significant differences in task performance between normal illumination (1,000lx level) and emergency illumination (100lx level), only if beyond the dark adaptation limit. However, subjective work load on mental demand and visual fatigue show a potential challenge to visual performance in drastic change of illumination. Conclusion/Application: Several trials can complement this challenge in NPPs by applying 3-way communication, enhancing readability of procedures, and managing the visual factors affecting the operators' performance through a Visual Environment Management Program including visual health aspects, etc.

Study on Effect of Learning Treatment Chart (의안(醫案) 학습효과에 대한 연구)

  • Kim, Yong-Chan;Shin, Hyeun-Kyoo;Kim, Byung-Soo;Kang, Jung-Soo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.19 no.3
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    • pp.580-585
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    • 2005
  • Treatment chart(醫案) is a document that doctors have described about their own practice. Western doctor's chart has a prescribed form, but otherwise chart of oriental medicine is a free form. As It has no prescribed form, doctors of oriental medicine have recorded important facts that they think especially. For example, details are patient's name, age, sex and address, the name of disease, state of pulse and tongue, state of secretions(stools, urine, perspiration, etc.), color of face, state of sleep and thirst, diagnosis, prescription, improvement of herb, teaching, and so forth. If we study on chart of oriental medicine, we draw a lesson about practices of a famous doctors. Through that we can increase ability of diagnosis and adaptation to circumstance, make ourselves familiar with use of past prescriptions and way of changing prescription, and learn narrative story of past doctors' personal experience, their though and teaching. As chart of oriental medicine had many methods to take a measure to meet the false situation, we can learn that. Through chart of oriental medicine, we can improve our practice of oriental medicine.

Circulatory and Respiratory Responses to Postural Changes (체위 변화에 수반되는 순환 및 호흡반응)

  • Chae, E-Up;Lee, Suck-Kang;Bae, Sung-Ho
    • The Korean Journal of Physiology
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    • v.7 no.1
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    • pp.13-21
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    • 1973
  • An attempt was made to study circulatory and respiratory responses to the passive tilt. Anesthetized dogs were tilted from horizontal to upright $(+90^{\circ})$ and head down $(-90^{\circ})$ position. The arterial blood pressure was decreased in the upright position and was decreased slightly in the head down position comparing to that in the horizontal position. Cardiac index also decreased in the both upright and head down positions. The total systemic vascular resistance was slightly increased in the upright position and was markedly increased in the head down position. The mean pulmonary arterial pressure was significantly decreased in the both upright and head down positions. The total pulmonary vascular resistance was decreased in the both upright and head down positions. Oxygen consumption was slightly decreased in the upright position, whereas it was slightly increased in the head down position. The A-V $O_2$ difference (vol. %) was slightly increased in the upright position and increased in the head down position. From the above results, process of the circulatory compensation to the gravity in the Passive tilting test was discussed. Neuronal cardiovascular regulation to the gravity and tile adaptation of capacitance vessles to hydrostatic stress and oxygen consumption concerning anoxic endurance of the brain were also discussed.

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Dynamic Energy Balance and Obesity Prevention

  • Yoo, Sunmi
    • Journal of Obesity & Metabolic Syndrome
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    • v.27 no.4
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    • pp.203-212
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    • 2018
  • Dynamic energy balance can give clinicians important answers for why obesity is so resistant to control. When food intake is reduced for weight control, all components of energy expenditure change, including metabolic rate at rest (resting energy expenditure [REE]), metabolic rate of exercise, and adaptive thermogenesis. This means that a change in energy intake influences energy expenditure in a dynamic way. Mechanisms associated with reduction of total energy expenditure following weight loss are likely to be related to decreased body mass and enhanced metabolic efficiency. Reducing calorie intake results in a decrease in body weight, initially with a marked reduction in fat free mass and a decrease in REE, and this change is maintained for several years in a reduced state. Metabolic adaptation, which is not explained by changes in body composition, lasts for more than several years. These are powerful physiological adaptations that induce weight regain. To avoid a typically observed weight-loss and regain trajectory, realistic weight loss goals should be established and maintained for more than 1 year. Using a mathematical model can help clinicians formulate advice about diet control. It is important to emphasize steady efforts for several years to maintain reduced weight over efforts to lose weight. Because obesity is difficult to reverse, clinicians must prioritize obesity prevention. Obesity prevention strategies should have high feasibility, broad population reach, and relatively low cost, especially for young children who have the smallest energy gaps to change.