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Mitochondrial Damage and Metabolic Compensatory Mechanisms Induced by Hyperoxia in the U-937 Cell Line

  • Scatena, Roberto;Messana, Irene;Martorana, Giuseppe Ettore;Gozzo, Maria Luisa;Lippa, Silvio;Maccaglia, Alessandro;Bottoni, Patrizia;Vincenzoni, Federica;Nocca, Giuseppina;Castagnola, Massimo;Giardina, Bruno
    • BMB Reports
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    • v.37 no.4
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    • pp.454-459
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    • 2004
  • Experimental hyperoxia represents a suitable in vitro model to study some pathogenic mechanisms related to oxidative stress. Moreover, it allows the investigation of the molecular pathophysiology underlying oxygen therapy and toxicity. In this study, a modified experimental set up was adopted to accomplish a model of moderate hyperoxia (50% $O_2$, 96 h culture) to induce oxidative stress in the human leukemia cell line, U-937. Spectrophotometric measurements of mitochondrial respiratory enzyme activities, NMR spectroscopy of culture media, determination of antioxidant enzyme activities, and cell proliferation and differentiation assays were performed. The data showed that moderate hyperoxia in this myeloid cell line causes: i) intriguing alterations in the mitochondrial activities at the levels of succinate dehydrogenase and succinate-cytochrome c reductase; ii) induction of metabolic compensatory adaptations, with significant shift to glycolysis; iii) induction of different antioxidant enzyme activities; iv) significant cell growth inhibition and v) no significant apoptosis. This work will permit better characterization the mitochondrial damage induced by hyperoxia. In particular, the data showed a large increase in the succinate cytochrome c reductase activity, which could be a fundamental pathogenic mechanism at the basis of oxygen toxicity.

Impacts of wave and tidal forcing on 3D nearshore processes on natural beaches. Part I: Flow and turbulence fields

  • Bakhtyar, R.;Dastgheib, A.;Roelvink, D.;Barry, D.A.
    • Ocean Systems Engineering
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    • v.6 no.1
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    • pp.23-60
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    • 2016
  • The major objective of this study was to develop further understanding of 3D nearshore hydrodynamics under a variety of wave and tidal forcing conditions. The main tool used was a comprehensive 3D numerical model - combining the flow module of Delft3D with the WAVE solver of XBeach - of nearshore hydro- and morphodynamics that can simulate flow, sediment transport, and morphological evolution. Surf-swash zone hydrodynamics were modeled using the 3D Navier-Stokes equations, combined with various turbulence models (${\kappa}-{\varepsilon}$, ${\kappa}-L$, ATM and H-LES). Sediment transport and resulting foreshore profile changes were approximated using different sediment transport relations that consider both bed- and suspended-load transport of non-cohesive sediments. The numerical set-up was tested against field data, with good agreement found. Different numerical experiments under a range of bed characteristics and incident wave and tidal conditions were run to test the model's capability to reproduce 3D flow, wave propagation, sediment transport and morphodynamics in the nearshore at the field scale. The results were interpreted according to existing understanding of surf and swash zone processes. Our numerical experiments confirm that the angle between the crest line of the approaching wave and the shoreline defines the direction and strength of the longshore current, while the longshore current velocity varies across the nearshore zone. The model simulates the undertow, hydraulic cell and rip-current patterns generated by radiation stresses and longshore variability in wave heights. Numerical results show that a non-uniform seabed is crucial for generation of rip currents in the nearshore (when bed slope is uniform, rips are not generated). Increasing the wave height increases the peaks of eddy viscosity and TKE (turbulent kinetic energy), while increasing the tidal amplitude reduces these peaks. Wave and tide interaction has most striking effects on the foreshore profile with the formation of the intertidal bar. High values of eddy viscosity, TKE and wave set-up are spread offshore for coarser grain sizes. Beach profile steepness modifies the nearshore circulation pattern, significantly enhancing the vertical component of the flow. The local recirculation within the longshore current in the inshore region causes a transient offshore shift and strengthening of the longshore current. Overall, the analysis shows that, with reasonable hypotheses, it is possible to simulate the nearshore hydrodynamics subjected to oceanic forcing, consistent with existing understanding of this area. Part II of this work presents 3D nearshore morphodynamics induced by the tides and waves.

Analysis of Convergent Factors Related to Job Satisfaction among Hospital Administrative Staff (병원행정직의 직무만족도와 관련된 융복합적 요인 분석)

  • Kim, Seung-Hee;Bae, Sang-Yun
    • Journal of Digital Convergence
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    • v.15 no.4
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    • pp.365-375
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    • 2017
  • This study is executed to investigate convergent factors to Job Satisfaction(JS) among Hospital Administrative Staff(HAS). The survey was administered to 221 staff from 11 general hospitals located in Jeonbuk area from Nov. 1st, 2016 to Jan. 31st, 2017. The structured self-administered questionaries were used. The hierarchical multiple regression analysis shows the following results. The JS of respondents turned out to be significantly higher in following groups: a group without work shift, a group with more employees, a group in which self efficacy is higher, a group in which skill variety in job characteristics is higher, a group in which interpersonal conflict and lack of reward in occupational stress are lower. The results show explanatory power of 61.0%. The results of the study indicate that the efforts, to increase self efficacy, and to manage job characteristics and occupational stress, are required to improve the JS among HAS. The results are expected to be useful for the program and human resource management to related to the JS among HAS. In the following study, the analysis of structural equation modeling about additional factors of the JS among HAS will be needed.

A Study on the Differences in Self-perceived Oral Health Levels in Workers at Seoul-Inchon Area (경인지역 근로자의 자기평가 구강건강수준 인식에 관한 연구)

  • Kim, Sook-Hyang;Hong, Min-Hee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.12
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    • pp.5692-5699
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    • 2011
  • This study aims to determine potential differences in self-perceived oral health levels between blue-collar and white-collar workers. It is based upon questionnaire survey data dating from Mar. 1 to 30, 2011. All the data collected from 200 blue-collar workers and 100 white-collar worker was analyzed using statistical tools like SPSS ver. 19.0. Self-perceived oral health levels were analysed across three sub-factors - physical, psycho-social, and psychological factors - which were confirmed through factor analysis. The psycho-social factor was statistically significant for age and shift work. Self-perceived oral health levels across the three factors were quantitatively correlated except for psychological factors in blue-collar workers. The study found that occupational group affects workers' self-perceived oral health level. The explanatory power of these 4 variables total 51% in blue-collar group. In case of white-collar group, it was found one variable total 30%. Since oral health levels differ between blue-collar and white-collar workers, oral health promotion projects should differentiate between the two groups, and workers with an interest in their tooth for the prevention, yet negligent act because it will keep your personal oral health care in the prevention-oriented oral health promotion.

Relationships Between Job Stress and Psychosocial Stress Among Nurses in a University Hospital (대학병원 간호사의 직무스트레스와 사회심리적 스트레스의 관련성)

  • Park, Sung-Kyeong;Kim, Jong-Oh;Cho, Young-Chae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.9
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    • pp.3887-3896
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    • 2011
  • This study was intended to measure the level of psychosocial stress among nurses working for a university hospital and to reveal its related factors. The self-administered questionnaires were given to 450 nurses during the period from October 1st to 31st, 2010. As a results, the level of psychosocial stress was 10.2% in normal group, 64.0% in potential stresses group, and 25.8% in high risk stress group. In correlation, psychosocial stress was positively correlated with job demand, but it was negatively correlated with job autonomy, supervisor and colleague support. For the results of hierarchial multiple regression analysis, the level of psychosocial stress was influenced by the variables of regular exercise, quality of sleep, subjective status of health, shift work, fit to the job, job demand, job autonomy and supervisor support. Especially, the psychosocial stress was higher related with the contents of job stress increased with explanatory powers of 18.1% on the psychosocial stress.

A Theory of Intermediality and its Application in Peter Greenaway's (상호매체성의 이론과 그 적용 - 피터 그리너웨이의 <프로스페로의 서재>를 중심으로)

  • PARK, Ki-Hyun
    • Cross-Cultural Studies
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    • v.19
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    • pp.39-77
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    • 2010
  • The cinema of Peter Greenaway has consistently engaged questions of the relationship between the arts and particularly the relations of image and writing to cinema. When different types of images are correlated and merged with each other on the borders of painting, photography, film, video and computer animation, the interrelationships of the distinct elements cause a shift in the notion of the whole image. This analysis proposes to articulate the complex relationship between the 'interartial' dimension and the 'intermedial' dimension in Peter Greenaway's film, (1991). If the interartiality is interested in the interaction between various arts, including the transition from one to another, the intermediality articulates the same type of relationship between two or more media. The interactional relationship is the same on both sides; on the contrary, the relationship between art and media does not show the same symmetry. All art is based on one or more media - the media is a condition existence of art - but no art can't be reduced to the status of media. This suggests that if the interartiality always involves the intermediality, this proposal may not be reversed. First, we analyse a self-conscious investigation into digital art and technology. Prosospero's Books can be read as a daring visual essay that self-consciously investigates the technical and philosophical functions of letters, books, images, animated paintings, digital arts, and the other magical illusions, which have been modern or will be post-modern media to represent the world. Greenaway uses both conventional film techniques and the resources of high-definition television to layer image upon image, superimposing a second or third frame within his frame. Greenaway uses the frame-within-frame as the cinematic equivalent of Shakespeare's paly-within-play : it offer him the possibility to analyse the work of art/artist/spectator relationship. Secondly, we analyse the relationship between the written word, oral word and the books. Like the written word, the oral word changes into a visual image: The linguistic richness and nuances of Shakeaspeare's characters turn into the powerful and authoritative, but monotone, voices of Gielgud-Prospero, who speaks the Shakespearean lines aloud, shaping the characters so powerfully through his worlds that they are conjured before us. Specially each book is placed over the frame of the play's action, only partially covering the image, so that it gives virtually every frame at least two space-time orientations. Thirdly, we try to show how Peter Greenaway uses pictorial references in order to illustrate the context of the Renaissance as well as pictorial techniques and language in order to question the nature of artistic representation. For exemple, The storm is visualised through reference to Botticelli's : the storm of papers swirling around the library is constructed to look like a facsimili copy of Michelangelo's Laurentiana Library in Florence. Greenaway's modern mannerism consists in imposing his own aesthetic vision and his questioning of art beyond the play's meta-theatricality: in other words, Shakespeare''s text has been adapted without being betrayed.

Constraints and opportunities to sustain future wheat yield and water productivity in semi-arid environment

  • Ahmad, Mirza Junaid;Choi, Kyung-Sook
    • Proceedings of the Korea Water Resources Association Conference
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    • 2019.05a
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    • pp.185-185
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    • 2019
  • Sustaining future wheat production is challenged by anthropogenically forced climate warming and drying led by increased concentration of greenhouse gases all around the globe. Warming stresses, originating from the elevated $CO_2$ concentration, are continuously reported to have negative impacts on wheat growth and yield. Yet, elevated $CO_2$ concentration, despite being disparagingly blamed for promoting warming, is also associated with a phenomenon called $CO_2$ enrichment; in which wheat yield can improve due to the enhanced photosynthesis rates and less water loss through transpiration. The conflicting nature of climate warming and $CO_2$ enrichment and their interplay can have specific implications under different environments. It is established form the field and simulation studies that the two contrasting phenomena would act severely in their own respect under arid and semi-arid environments. Wheat is a dietary staple for masses in Pakistan. The country's wheat production system is under constant stress to produce more from irrigated agricultural lands, primarily lying under arid to semi-arid environments, to meet the rapidly growing domestic needs. This work comprehensively examines the warming impacts over wheat yield and water productivity (WP), with and without the inclusion of $CO_2$ enrichment, under semi-arid environment of Punjab which is the largest agricultural province of Pakistan. Future wheat yields and WPs were simulated by FAO developed AquaCrop model v 5.0. The model was run using the bias-correction climate change projections up to 2080 under two representative concentration pathways (RCP) scenarios: 4.5 and 8.5. Wheat yield and WPs decreased without considering the $CO_2$ enrichment effects owing to the elevated irrigation demands and accelerated evapotranspiration rates. The results suggested that $CO_2$ enrichment could help maintain the current yield and WPs levels during the 2030s (2021-2050); however, it might not withhold the negative climate warming impacts during the 2060s (2051-2080). Furthermore, 10 - 20 day backward shift in sowing dates could also help ease the constraints imposed by climate warming over wheat yields and WPs. Although, $CO_2$ enrichment showed promises to counteract the adverse climate warming impacts but the interactions between climate warming and $CO_2$ concentrations were quite uncertain and required further examination.

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A Methodology for Analyzing on the Correlation of Factors Affecting the Acquisition of Military Weapons Systems : Focused on Factor Analysis of Naval Ship Acquisition Delay Cases (국방무기체계 획득영향요인 상호관계 분석 : 함정획득지연 사례 및 요인 분석을 중심으로)

  • Hwang, Jeong-Oh;Oh, Hyun-Seung;Choi, Bong-Wan;Yim, Dong-Soon
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.43 no.4
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    • pp.48-58
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    • 2020
  • Naval weapons systems of the Republic of Korea are acquired through the Defense Planning Management System. Recently, acquisition of some naval ships have been delayed, and the causes of the delays have been recognized as inappropriate project management at the Execution Phase. However, we argue that the delay problem in naval ships acquisition should be approached, with due regard for the entire Defense Planning Management System. That is, We should try to investigate from Planning Phase to those of Programming, Budgeting and Execution Phases. Therefore, in this study, we investigated the actual cases of the delay in naval acquisition at all phases of the Defense Planning Management System. Based on the investigation, we tried to identify the naval ship Acquisition Delay Factors and find out the Weights of those factors. As the next step, we calculated the Influence Measures on the naval missions, including the Cost of Naval Capability Gap derived from the delays in acquisition of naval ships. As a final step, we calculated the Acquisition Delay Measures based on the interrelationship between the Acquisition Delay Factors and the Influence Measures. Then we evaluated and analyzed what the results stand for. Finally, we made suggestions for future improvement. The improvement suggestions we made for preventing delay in acquisition of naval ships in this study are as follows. First, we need a shift in perception. It is necessary to measure the Acquisition Delay Factors in acquiring naval ships and manage them from the Planning Phase. Second, resolution must be concerted efforts. All relevant agencies, not just a few, should work together to resolve the problems of acquisition delay. Third, analysis must be based on the accumulation of data. This allows the elaborating of naval ship Acquisition Delay Factors and Delay Measures. If this research method is applied to other military weapons systems in the future, we may be able to not just identify the Acquisition Delay Factors in acquisition of other military weapons systems, but also pursue improvement in those cases.

A Study on the Motif of 'Book Travel' in Korean Web Novel -Focused on Romance Fantasy Genre (한국 웹소설의 '책빙의물'의 특성 연구 -로맨스판타지 장르를 중심으로)

  • Ahn, Sang-Won
    • Journal of Popular Narrative
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    • v.26 no.3
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    • pp.87-120
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    • 2020
  • The study noted the characteristics of the web novel's 'Book Travel' motif, which reflects the characteristics of popular culture content, which is free to use familiar genre grammar or code. The imagination of the main character entering the work he read in the real world is a reinterpretation of the existing genre grammar of the web novel, and studying the motif is meaningful in reviewing the intertext of the genre. This motif, summarized as 'Book Travel' differs from other genres in the romance fantasy genre, which can also be used to reveal the gender characteristics of the genre. The study noted that the 'Book Travel' motif was born from an interactive interpretation of existing narratives, thus having a affinity with dimensional shift, regression, and alternative historical objects, and referring to the writing norms of Fanfiction. Through this, it was predicted that the re-combination of existing narratives and interference between genres would continue in the future. Next, the original move in the romance fantasy genre was seen as quite conservative and revealing the logic of self-improvement even though people around him became the main characters and overthrew the narrative. The characters should use their knowledge of the future of the real world to fight in a world of survival where destruction has been predicted. The appearance of an ethical and self-help subject is interesting, but on the other hand, I could look at conservatism in that romance is a way of survival and achievement of characters. The research is meaningful in that it reviewed the characteristics of the original transfer motif, which started fairly quickly in the romance fantasy genre, and reviewed its appearance background and characteristics. There was a limit to the collection of physical works and limited platform. The above limits are intended to be supplemented by further reviewing and supplementing later works.

Aromatic Agriculture: Volatile Compound-Based Plant Disease Diagnosis and Crop Protection (향기농업: 휘발성 물질을 이용한 식물병 진단과 방제)

  • Riu, Myoungjoo;Son, Jin-Soo;Oh, Sang-Keun;Ryu, Choong-Min
    • Research in Plant Disease
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    • v.28 no.1
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    • pp.1-18
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    • 2022
  • Volatiles exist ubiquitously in nature. Volatile compounds produced by plants and microorganisms confer inter-kingdom and intra-kingdom communications. Autoinducer signaling molecules from contact-based chemical communication, such as bacterial quorum sensing, are relayed through short distances. By contrast, biogenic volatiles derived from plant-microbe interactions generate long-distance (>20 cm) alarm signals for sensing harmful microorganisms. In this review, we discuss prior work on volatile compound-mediated diagnosis of plant diseases, and the use of volatile packaging and dispensing approaches for the biological control of fungi, bacteria, and viruses. In this regard, recent developments on technologies to analyze and detect microbial volatile compounds are introduced. Furthermore, we survey the chemical encapsulation, slow-release, and bio-nano techniques for volatile formulation and delivery that are expected to overcome limitations in the application of biogenic volatiles to modern agriculture. Collectively, technological advances in volatile compound detection, packaging, and delivery provide great potential for the implementation of ecologically-sound plant disease management strategies. We hope that this review will help farmers and young scientists understand the nature of microbial volatile compounds, and shift paradigms on disease diagnosis and management to aromatic (volatile-based) agriculture.