• Title/Summary/Keyword: Stress Reactions

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Future Prospects for Industrial Application of Abscisic acid, a Stress-resistant Phytohormone (스트레스 내성 식물 호르몬인 앱시스산의 산업적 활용 전망)

  • Lee, Jeongho;Kim, Seunghee;Yoo, Hah Young
    • Korean Chemical Engineering Research
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    • v.58 no.4
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    • pp.514-523
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    • 2020
  • Plants are exposed to various types of stresses in their surroundings, and stress-resistant and regulatory proteins are produced as defense mechanisms. Abscisic acid is well known for its important role in stress signals as a phytohormone and is also involved in the physiological reactions of plants such as leaf senescence and seed dormancy. In particular, it has been found to perform a variety of functions in other biological systems, such as animals and microalgae, not plants. In this review, the biosynthesis and signaling process of abscisic acid and its function were investigated and the future prospects for the industrial application of abscisic acid in various biotechnologies, including agriculture, biomedical and industrial biotechnology, have been proposed based on study of emerging applications such as increased crop yields, disease treatment development and bioenergy production.

Response of Saccharomyces cerevisiae to Ethanol Stress Involves Actions of Protein Asr1p

  • Ding, Junmei;Huang, Xiaowei;Zhao, Na;Gao, Feng;Lu, Qian;Zhang, Ke-Qin
    • Journal of Microbiology and Biotechnology
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    • v.20 no.12
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    • pp.1630-1636
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    • 2010
  • During the fermentation process of Saccharomyces cerevisiae, yeast cells must rapidly respond to a wide variety of external stresses in order to survive the constantly changing environment, including ethanol stress. The accumulation of ethanol can severely inhibit cell growth activity and productivity. Thus, the response to changing ethanol concentrations is one of the most important stress reactions in S. cerevisiae and worthy of thorough investigation. Therefore, this study examined the relationship between ethanol tolerance in S. cerevisiae and a unique protein called alcohol sensitive RING/PHD finger 1 protein (Asr1p). A real-time PCR showed that upon exposure to 8% ethanol, the expression of Asr1 was continuously enhanced, reaching a peak 2 h after stimulation. This result was confirmed by monitoring the fluorescence levels using a strain with a green fluorescent protein tagged to the C-terminal of Asr1p. The fluorescent microscopy also revealed a change in the subcellular localization before and after stimulation. Furthermore, the disruption of the Asr1 gene resulted in hypersensitivity on the medium containing ethanol, when compared with the wild-type strain. Thus, when taken together, the present results suggest that Asr1 is involved in the response to ethanol stress in the yeast S. cerevisiae.

Current Status of 119 EMT to Violence Experiences (119 구급대원이 경험하는 폭력에 대한 실태조사)

  • Choi, Eun-Sook;Kim, Hee-Jung;Cho, Won-Min;Kang, Dae-Hun
    • The Korean Journal of Emergency Medical Services
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    • v.13 no.3
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    • pp.91-105
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    • 2009
  • Purpose : The purpose of this study was to describe the current status of 119 EMT to violence experiences in Korea. Method : The number of 119 EMT in this study 2522. Self-administering questionnaire data were collected from April 27 to March 8 in 2009. Collected data were analyzed using SPSS 14.0 program. Real number, percentage, mean and standard deviation were calculated. Pearson correlation coefficient was analyzed. Result : 119 EMTs experienced 95.32%-verbal insults, 61.54%-violence aggression, 60.51%- potential violence, 38.70%-physical assault. Within 30 days from the most recent period of violence experienced verbal insults and violence aggression-51.07%, potential violence and physical assault-48.41%. The patients(50.59%) and the patients and patient's carers(38.26%) proved to be violent offender. The main reason of violent act was drug or alcohol addiction(56.15%). Recent exposure to violence was 34.82% by 7 point reward of stress level. 5-point scale showed the average of experiences of violence. Response average of emotional reactions was 2.66 points and that of physical reaction was 2.18 points. Social reaction was 2.06 points. Conclusion : This study was based on the violence experience of 119 EMT. It is necessary to prevent the violence from emergency scene. So we proposed the preventive measure against violence as well as critical incident stress debriefing(CISD). Policy for CISD and stress management will be implemented in the near future in Korea.

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An Analysis of Consumers' Problematic Complaining Behaviors and Firms' Reactions (소비자의 악성불평행동 분석 및 기업의 대처행동 조사 연구)

  • Huh, Kyung-Ok
    • Journal of Families and Better Life
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    • v.30 no.6
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    • pp.167-181
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    • 2012
  • This study analyzed consumer's harsh complaining behaviors and firm's reactions toward consumers' harsh complaining behavior, and investigated the differences in the firms' reactions according to the characteristics of counselors and customer service centers. In addition, this study attempted to find a strategy and provide guidance regarding consumer's harsh complaining behaviors. The results of this study are discussed below. First, consumer's harsh complaining attitudes were expressed by crude language, violent language, threats, personal attacks, and claims of a high-ranking social position. Consumer's directive, complaining behaviors were repeated on the telephone, and threats of prosecution or disclosure to the public, exposure of habitual product returns, and requests for interviews with superiorsat the representative firm were made. Second, a firm typologies according to its reaction style toward a consumer's harsh complaining behaviors were as follows: Group 1, having a neutral attitude toward consumers and preparation thoroughly regarding their demands; Group 2, having a negative attitude toward consumers and some degree of preparation toward consumers' demands; and finally, Group 3, having a positive attitude toward consumers but offering insufficient reparation regarding consumers' demands. Third, female counselors, counselors having a certified counselor's license, and those much experience working in labor work were more likely to be in Group 3. Male counselors, part-time counselors, and those having experience of many years were more likely to be in Group 2. Group 1 were more likely to have large number of workers at customer service centers, male counselors, and to have large numbers of educational training programs related to the reactions of consumers in the form of dissatisfaction, complaints, how to offer compensation for injuries to consumers, and issues related to PL(product liability). In addition, Group 1 also had more firm level welfare policies related to hight stress levels of consumer counselors and extra types of support regarding harsh consumers. However, Group 2 members were more likely to provide excessive compensation and rewards to harsh consumers. Finally, to react to consumer's harsh complaint efficiently, it was suggested that firms should not treat consumers as harsh consumers, should react to consumers' complaints sincerely, and should take precautionary management efforts as regards consumer dissatisfaction based on better quality control of products. In addition, it was deemed necessary to formulate a management strategy to train competent consumer counselors with a high quality of counselor skill, having standardized and consistent reaction guidance toward consumer complaints and thorough knowledge of compensation rules for consumer injuries and subsequent guidance.

Gene-Diet Interaction on Cancer Risk in Epidemiological Studies

  • Lee, Sang-Ah
    • Journal of Preventive Medicine and Public Health
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    • v.42 no.6
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    • pp.360-370
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    • 2009
  • Genetic factors clearly play a role in carcinogenesis, but migrant studies provide unequivocal evidence that environmental factors are critical in defining cancer risk. Therefore, one may expect that the lower availability of substrate for biochemical reactions leads to more genetic changes in enzyme function; for example, most studies have indicated the variant MTHFR genotype 677TT is related to biomarkers, such as homocysteine concentrations or global DNA methylation particularly in a low folate diet. The modification of a phenotype related to a genotype, particularly by dietary habits, could support the notion that some of inconsistencies in findings from molecular epidemiologic studies could be due to differences in the populations studied and unaccounted underlying characteristics mediating the relationship between genetic polymorphisms and the actual phenotypes. Given the evidence that diet can modify cancer risk, gene-diet interactions in cancer etiology would be anticipated. However, much of the evidence in this area comes from observational epidemiology, which limits the causal inference. Thus, the investigation of these interactions is essential to gain a full understanding of the impact of genetic variation on health outcomes. This report reviews current approaches to gene-diet interactions in epidemiological studies. Characteristics of gene and dietary factors are divided into four categories: one carbon metabolism-related gene polymorphisms and dietary factors including folate, vitamin B group and methionines; oxidative stress-related gene polymorphisms and antioxidant nutrients including vegetable and fruit intake; carcinogen-metabolizing gene polymorphisms and meat intake including heterocyclic amins and polycyclic aromatic hydrocarbon; and other gene-diet interactive effect on cancer.

Oxidative Modification of Neurofilament-L by Copper-catalyzed Reaction

  • Kim, Nam-Hoon;Kang, Jung-Hoon
    • BMB Reports
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    • v.36 no.5
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    • pp.488-492
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    • 2003
  • Neurofilament-L (NF-L) is a major element of neuronal cytoskeletons and known to be important for neuronal survival in vivo. Since oxidative stress might play a critical role in the pathogenesis of neurodegenerative diseases, we investigated the role of copper and peroxide in the modification of NF-L. When disassembled NF-L was incubated with copper ion and hydrogen peroxide, then the aggregation of protein was proportional to copper and hydrogen peroxide concentrations. Dityrosine crosslink formation was obtained in copper-mediated NF-L aggregates. The copper-mediated modification of NF-L was significantly inhibited by thiol antioxidants, N-acetylcysteine, glutathione, and thiourea. A thioflavin-T binding assay was performed to determine whether the copper/$H_2O_2$ system-induced in vitro aggregation of NF-L displays amyloid-like characteristics. The aggregate of NF-L displayed thioflavin T reactivity, which was reminiscent of amyloid. This study suggests that copper-mediated NF-L modification might be closely related to oxidative reactions which may play a critical role in neurodegenerative diseases.

LIPID-SOLUBLE VC DERIVATIVE ASCORBIC ACID TETRA-2-HEXYLDECANOATE (VC-IP) AS AN ANTI-AGING AGENT

  • Obayashi, K.;Ochiai, Y.;Ochiai, Y.;Masaki, H.;Kurata, Y.
    • Proceedings of the SCSK Conference
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    • 2003.09a
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    • pp.313-319
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    • 2003
  • It is well known that ascorbic acid (VC) is an important factor for several physiological reactions. In the skin, VC works as an anti-aging agent due to removing of oxidative stress generated by UV irradiation and stimulation of collagen synthesis. Thus, developing more effective VC derivatives is an important issue in creating anti-aging skin care products. Our study succeeded to develop a novel ascorbic acid derivative, ascorbic acid tetra-2-hexyldecanoate (VC-IP), which is a lipid-soluble pro-VC. The purpose of this study was to indicate the effects of VC-IP as pro-VC and anti-aging agent. First, it was examined whether VC-IP is converted to VC in physiological conditions. Since VC was detected from the cell extracts treated with VC-IP, it was indicated that VC-IP is a pro- VC.(omiited)

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Lifetime Estimation due to IMC(Intermetallic Compound) formation between Au wire and Al pad (Au wire와 Al pad사이의 IMC(Intermetallic Compound) 형성에 의한 수명예측)

  • Son, Jung-Min;Chang, Mi-Soon;Kwack, Kae-Dal
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.1295-1300
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    • 2008
  • During the manufacturing and the service life of Au-Al wire bonded electronic packages, the ball bonds experience elevated temperatures and hence accelerated thermal diffusion reactions that promote the transformation of the Au-Al phases and the IMC growth. In this paper, the IC under high temperature storage (HTS) tests at $175^{\circ}C,\;200^{\circ}C$, and $250^{\circ}C$ are meticulously investigated. Thermal exposure resulted in the IMC growth, Kirkendall void and the crack of the Au-Al phases. The crack propagation occurs resulting in the failure of the Au-Al ball bonds. As the IC was exposed at the high temperature, decreased in the lifetime.

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Stress Analysis of Top Hat Type Structure for Random Loading

  • M. J. Jhung;Kim, Y. B.;Lee, J. B.
    • Nuclear Engineering and Technology
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    • v.29 no.6
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    • pp.476-487
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    • 1997
  • To resolve several arguments raised for the current analysis of a structure like top hat, which is composed of flange, cylinder and plate, the dynamic response analysis is performed for the full and half models. The dynamic characteristics are investigated for full and half models and the results are compared between them. The responses such as bolt reactions and stresses due to random loading are also obtained using the analysis capabilities between commercial programs which have the routine for the random vibration analysis. Several general purpose structural analysis programs are used to get the response due to the random loadings. Also the application of the random loading and the effect of correlations such as fully correlated, partially correlated and fully uncorrelated cases are studied and the general directions for the generation of design loads due to random loading are suggested.

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Stress Analysis of Top Hat Type Structure for Random Loading

  • Jhung, Myung-Jo;Hwang, Jong-Keun
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.05d
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    • pp.223-228
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    • 1996
  • To resolve several arguments raised for the current analysis of a structure like top hat, which is composed of flange, cylinder and plate, the dynamic response analysis is performed for the full and half models. The dynamic characteristics are investigated for full and half models and the results are compared between them. The responses such as bolt reactions and stresses due to random loading are also obtained using the analysis capabilities between commercial programs which have the routine for the random vibration analysis. Several general purpose structural analysis programs are used to get the response due to the random loadings. Also the application of the random loading and the effect of correlations are studied and the general directions for the generation of design load due to random loading are suggested.

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