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Steroid Effect on the Brain Protection During OPen Heart Surgery Using Hypothermic Circulatory Arrest in the Rabbit Cardiopulmonary bypass Model (저체온순환정지법을 이용한 개심술시 스테로이드의 뇌보호 효과 - 토끼를 이용한 심폐바이패스 실험모델에서 -)

  • Kim, Won-Gon;Lim, Cheong;Moon, Hyun-Jong;Chun, Eui-Kyung;Chi, Je-Geun;Won, Tae-Hee;Lee, Young-Tak;Chee, Hyun-Keun;Kim, Jun-Woo
    • Journal of Chest Surgery
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    • v.30 no.5
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    • pp.471-478
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    • 1997
  • Introduction: The use of rabbits as a cardiopulmonary bypass(CPB) animal model is extremely dif%cult mainly due to technical problems. On the other hand, deep hypothermic circulatory arrest(CA) is used to facilitate surgical repair in a variety of cardiac diseases. Although steroids are generally known to be effective in the treatment of cerebral edema, the protective effects of steroids on the brain during CA are not conclusively established. Objectives of this study are twofold: the establishment of CPB technique in rabbits and the evaluation of preventive effect of steroid on the development of brain edema during CA. Material '||'&'||' Methods: Fifteen New Zealan white rabbits(average body weight 3.5kg) were divided into three experimental groups; control CA group(n=5), CA with Trendelenberg position group(n=5), and CA with Trendelenberg position + steroid(methylprednisolone 30 mglkg) administration group(n=5). After anesthetic induction and tracheostomy, a median sternotomy was performed. An aortic cannula(3.3mm) and a venous ncannula(14 Fr) were inserted, respectively in the ascending aorta and the right atrium. The CPB circuit consisted of a roller pump and a bubble oxygenator. Priming volume of the circuit was approximately 450m1 with 120" 150ml of blood. CPB was initiated at a flow rate of 80~85ml/kg/min, Ten min after the start of CPB, CA was established with duration of 40min at $20^{\circ}C$ of rectal temperature. After CA, CPB was restarted with 20min period of rewarming. Ten min after weaning, the animal was sacrif;cod. One-to-2g portions of the following tissues were rapidly d:ssected and water contents were examined and compared among gr ups: brain, cervical spinal cord, kidney, duodenum, lung, heart, liver, spleen, pancreas. stomach. Statistical significances were analyzed by Kruskal-Wallis nonparametric test. Results: CPB with CA was successfully performed in all cases. Flow rate of 60-100 mlfkgfmin was able to be maintained throughout CPB. During CPB, no significant metabolic acidosis was detected and aortic pressure ranged between 35-55 mmHg. After weaning from CPB, all hearts resumed normal beating spontaneously. There were no statistically significant differences in the water contents of tissues including brain among the three experimental groups. Conclusion: These results indicate (1) CPB can be reliably administered in rabbits if proper technique is used, (2) the effect of steroid on the protection of brain edema related to Trendelenburg position during CA is not established within the scope of this experiment.

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Application of Support Vector Regression for Improving the Performance of the Emotion Prediction Model (감정예측모형의 성과개선을 위한 Support Vector Regression 응용)

  • Kim, Seongjin;Ryoo, Eunchung;Jung, Min Kyu;Kim, Jae Kyeong;Ahn, Hyunchul
    • Journal of Intelligence and Information Systems
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    • v.18 no.3
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    • pp.185-202
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    • 2012
  • .Since the value of information has been realized in the information society, the usage and collection of information has become important. A facial expression that contains thousands of information as an artistic painting can be described in thousands of words. Followed by the idea, there has recently been a number of attempts to provide customers and companies with an intelligent service, which enables the perception of human emotions through one's facial expressions. For example, MIT Media Lab, the leading organization in this research area, has developed the human emotion prediction model, and has applied their studies to the commercial business. In the academic area, a number of the conventional methods such as Multiple Regression Analysis (MRA) or Artificial Neural Networks (ANN) have been applied to predict human emotion in prior studies. However, MRA is generally criticized because of its low prediction accuracy. This is inevitable since MRA can only explain the linear relationship between the dependent variables and the independent variable. To mitigate the limitations of MRA, some studies like Jung and Kim (2012) have used ANN as the alternative, and they reported that ANN generated more accurate prediction than the statistical methods like MRA. However, it has also been criticized due to over fitting and the difficulty of the network design (e.g. setting the number of the layers and the number of the nodes in the hidden layers). Under this background, we propose a novel model using Support Vector Regression (SVR) in order to increase the prediction accuracy. SVR is an extensive version of Support Vector Machine (SVM) designated to solve the regression problems. The model produced by SVR only depends on a subset of the training data, because the cost function for building the model ignores any training data that is close (within a threshold ${\varepsilon}$) to the model prediction. Using SVR, we tried to build a model that can measure the level of arousal and valence from the facial features. To validate the usefulness of the proposed model, we collected the data of facial reactions when providing appropriate visual stimulating contents, and extracted the features from the data. Next, the steps of the preprocessing were taken to choose statistically significant variables. In total, 297 cases were used for the experiment. As the comparative models, we also applied MRA and ANN to the same data set. For SVR, we adopted '${\varepsilon}$-insensitive loss function', and 'grid search' technique to find the optimal values of the parameters like C, d, ${\sigma}^2$, and ${\varepsilon}$. In the case of ANN, we adopted a standard three-layer backpropagation network, which has a single hidden layer. The learning rate and momentum rate of ANN were set to 10%, and we used sigmoid function as the transfer function of hidden and output nodes. We performed the experiments repeatedly by varying the number of nodes in the hidden layer to n/2, n, 3n/2, and 2n, where n is the number of the input variables. The stopping condition for ANN was set to 50,000 learning events. And, we used MAE (Mean Absolute Error) as the measure for performance comparison. From the experiment, we found that SVR achieved the highest prediction accuracy for the hold-out data set compared to MRA and ANN. Regardless of the target variables (the level of arousal, or the level of positive / negative valence), SVR showed the best performance for the hold-out data set. ANN also outperformed MRA, however, it showed the considerably lower prediction accuracy than SVR for both target variables. The findings of our research are expected to be useful to the researchers or practitioners who are willing to build the models for recognizing human emotions.

Genetic Diversity of Korean Native Chicken Populations in DAD-IS Database Using 25 Microsatellite Markers (초위성체 마커를 활용한 가축다양성정보시스템(DAD-IS) 등재 재래닭 집단의 유전적 다양성 분석)

  • Roh, Hee-Jong;Kim, Kwan-Woo;Lee, Jinwook;Jeon, Dayeon;Kim, Seung-Chang;Ko, Yeoung-Gyu;Mun, Seong-Sil;Lee, Hyun-Jung;Lee, Jun-Heon;Oh, Dong-Yep;Byeon, Jae-Hyun;Cho, Chang-Yeon
    • Korean Journal of Poultry Science
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    • v.46 no.2
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    • pp.65-75
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    • 2019
  • A number of Korean native chicken(KNC) populations were registered in FAO (Food and Agriculture Organization) DAD-IS (Domestic Animal Diversity Information Systems, http://www.fao.org/dad-is). But there is a lack of scientific basis to prove that they are unique population of Korea. For this reason, this study was conducted to prove KNC's uniqueness using 25 Microsatellite markers. A total of 548 chickens from 11 KNC populations (KNG, KNB, KNR, KNW, KNY, KNO, HIC, HYD, HBC, JJC, LTC) and 7 introduced populations (ARA: Araucana, RRC and RRD: Rhode Island Red C and D, LGF and LGK: White Leghorn F and K, COS and COH: Cornish brown and Cornish black) were used. Allele size per locus was decided using GeneMapper Software (v 5.0). A total of 195 alleles were observed and the range was 3 to 14 per locus. The MNA, $H_{\exp}$, $H_{obs}$, PIC value within population were the highest in KNY (4.60, 0.627, 0.648, 0.563 respectively) and the lowest in HYD (1.84, 0.297, 0.286, 0.236 respectively). The results of genetic uniformity analysis suggested 15 cluster (${\Delta}K=66.22$). Excluding JJC, the others were grouped in certain cluster with high genetic uniformity. JJC was not grouped in certain cluster but grouped in cluster 2 (44.3%), cluster 3 (17.7%) and cluster8 (19.1%). As a results of this study, we can secure a scientific basis about KNC's uniqueness and these results can be use to basic data for the genetic evaluation and management of KNC breeds.

Combined Effect of Ganciclovir and Vidarabine on the Replication, DNA Synthesis, and Gene Expression of Acyclovir-resistant Herpes Simplex Virus (Acyclovir저항성 Herpes Simplex Virus의 복제, DNA합성 및 형질 발현에 미치는 Ganciclovir 및 Vidarabine의 병용효과에 관한 연구)

  • Yang, Young-Tai;Cheong, Dong-Kyun;Mori, Masakazu
    • The Korean Journal of Pharmacology
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    • v.25 no.1
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    • pp.115-134
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    • 1989
  • Combined effects of ganciclovir (GCV) and vidarabine (ara-A) on the replication, DNA synthesis, and gene expression of wild type-1 herpes simplex virus (HSV-1) and three acyclovir (ACV)-resistant HSV-1 mutants were studied. These mutants include a virus expressing no thymidine kinase $(ACV^r)$, a virus expressing thymidine kinase with altered substrate specificity $(IUdR^r)$, and a mutant expressing altered DNA polymerase $(PAA^r5)$. GCV, an agent activated by herpesvirus specific thymidine kinase, showed potent antiviral activity against the wild type HSV-1(KOS) and DNA polymerase mutant $(PAA^r5)$. The ACV-resistant mutants with thymidine kinase gene $(ACV^r\;and\;IUdR^r)$ were resistant to GCV. All tested wild type HSV-1 or ACV-resistant HSV-1 mutants did not display resistance to vidarabine (are-A). Combined GCV and ara-A showed potentiating synergistic antiviral activity against wild type KOS and $PAA^r5$, and showed subadditive combnined ativiral activity against thymidine kinase mutants. Combined GCV and ara-A more significantly inhibited the viral DNA synthesis in wild type KOS and $PAA^r5-infected$ cells to a greater extent than either agent alone, but the synergism was not determined in $ACV^r$ or $IUdR^r-infected$ cells. These data clearly indicate that combined GCV and ara-A therapy might be useful for the treatment of infections caused by wild type HSV-1 or ACV-resistant HSV-1 with DNA polymerase mutation. ACV-resistant viruses with the mutation in thymidine kinase gene are also, resistant to GCV, but susecptible to ara-A, indicating that ara-A would the drug of choice for the treatment of ACV-resistant HSV-1 which does not express thymidine kinase or expresses thymidine kinase with altered substrate specificity. While the synthesis of viral ${\alpha}-proteins$ of wild type HSV-1 was not affected by ACV, GCV, ara-A, or combined GCV and ara-A, the synthesis of ${\beta}-proteins$ was slightly but significantly increased at the later stage of viral infection by the antiviral agents. The synthesis of ${\gamma}-proteins$ of wild type HSV- 1 was significantly inhibited by ACV, GCV, ara-A, and combined GCV and ara-A. Combined GCV $(5-{\mu}M)$ and ara-A $(100-{\mu}M)$ also significantly altered the expression of viral ${\beta}-and$ ${\gamma}-proteins$, of which efffct was similar to that of GCV $(10-{\mu}M)$ alone. Although ACV at the concentration of $10-{\mu}M$ did not alter the expression of ${\alpha}-$, ${\beta}-$, and ${\gamma}-proteins$ of ACV-resistant $PAA^r5$, GCV and ara-A significantly alter the epression of ${\beta}-and$ ${\gamma}-proteins$, not ${\alpha}-protein$, as same manner as they altered the expression of those proteins in cells inffcted with wild type HSV-1. Combined GCV $(5-{\mu}M)$ and ara-A $(100-{\mu}M)$ altered the expression ${\beta}-and$ ${\gamma}-proteins$ in $PAA^r5$ infected cells, and the effect of combined regimen was comparable of that of GCV $(10-{\mu}M)$. These data indicate that the alteration in the expression of ${\beta}-and$ ${\gamma}-proteins$ in wild type HSV-1 or $PAA^r5$ infected cells could be more significantly affected by combined GCV and are-A than individual GCV or ara-A. In view of the fact that (a) viral ${\alpha}-$, ${\beta}-$, and ${\gamma}-proteins$ are synthesized in a cascade manner; (b) ${\beta}-proteins$ are essential for the synthesis of viral DNA; (c) the synthesis of ${\beta}-proteins$ are inhibited by ${\gamma}-proteins$; and (d) most ${\gamma}-proteins$ are made from the newly synthesized progeny virus, it is suggested that GCV and ara-A, alone or in combination, primarily inhibit the synthesis of viral DNA, and by doing so might exhibit their antiherpetic activity. The alteration in viral protein synthesis in the presence of tested antiviral agents could result from the alteration in viral DNA synthesis. From the present study, it can be concluded that (a) combined GCV and ara-A therapy would be beneficial for the control of inffctions caused by wild type HSV-1 or ACV-resistant DNA polymerase mutants; (b) the combined synergistic activity of GCV and ara-A is due to further decrease in the viral DNA by the combined regimen; (c) ara-A is the drug of choice for the infection caused by ACV-resistant HSV-1 with thymidine kinase mutation; and (d) the alteration in viral protein synthesis by GCV and ars-A, alone or in combination, is mostly due to the decreased synthesis of viral DAN.

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A Study on the Relationship Between Online Community Characteristics and Loyalty : Focused on Mediating Roles of Self-Congruency, Consumer Experience, and Consumer to Consumer Interactivity (온라인 커뮤니티 특성과 충성도 간의 관계에 대한 연구: 자아일치성, 소비자 체험, 상호작용성의 매개적 역할을 중심으로)

  • Kim, Moon-Tae;Ock, Jung-Won
    • Journal of Global Scholars of Marketing Science
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    • v.18 no.4
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    • pp.157-194
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    • 2008
  • The popularity of communities on the internet has captured the attention of marketing scholars and practitioners. By adapting to the culture of the internet, however, and providing consumer with the ability to interact with one another in addition to the company, businesses can build new and deeper relationships with customers. The economic potential of online communities has been discussed with much hope in the many popular papers. In contrast to this enthusiastic prognostications, empirical and practical evidence regarding the economic potential of the online community has shown a little different conclusion. To date, even communities with high levels of membership and vibrant social arenas have failed to build financial viability. In this perspective, this study investigates the role of various kinds of influencing factors to online community loyalty and basically suggests the framework that explains the process of building purchase loyalty. Even though the importance of building loyalty in an online environment has been emphasized from the marketing theorists and practitioners, there is no sufficient research conclusion about what is the process of building purchase loyalty and the most powerful factors that influence to it. In this study, the process of building purchase loyalty is divided into three levels; characteristics of community site such as content superiority, site vividness, navigation easiness, and customerization, the mediating variables such as self congruency, consumer experience, and consumer to consumer interactivity, and finally various factors about online community loyalty such as visit loyalty, affect, trust, and purchase loyalty are those things. And the findings of this research are as follows. First, consumer-to-consumer interactivity is an important factor to online community purchase loyalty and other loyalty factors. This means, in order to interact with other people more actively, many participants in online community have the willingness to buy some kinds of products such as music, content, avatar, and etc. From this perspective, marketers of online community have to create some online environments in order that consumers can easily interact with other consumers and make some site environments in order that consumer can feel experience in this site is interesting and self congruency is higher than at other community sites. It has been argued that giving consumers a good experience is vital in cyber space, and websites create an active (rather than passive) customer by their nature. Some researchers have tried to pin down the positive experience, with limited success and less empirical support. Web sites can provide a cognitively stimulating experience for the user. We define the online community experience as playfulness based on the past studies. Playfulness is created by the excitement generated through a website's content and measured using three descriptors Marketers can promote using and visiting online communities, which deliver a superior web experience, to influence their customers' attitudes and actions, encouraging high involvement with those communities. Specially, we suggest that transcendent customer experiences(TCEs) which have aspects of flow and/or peak experience, can generate lasting shifts in beliefs and attitudes including subjective self-transformation and facilitate strong consumer's ties to a online community. And we find that website success is closely related to positive website experiences: consumers will spend more time on the site, interacting with other users. As we can see figure 2, visit loyalty and consumer affect toward the online community site didn't directly influence to purchase loyalty. This implies that there may be a little different situations here in online community site compared to online shopping mall studies that shows close relations between revisit intention and purchase intention. There are so many alternative sites on web, consumers do not want to spend money to buy content and etc. In this sense, marketers of community websites must know consumers' affect toward online community site is not a last goal and important factor to influnece consumers' purchase. Third, building good content environment can be a really important marketing tool to create a competitive advantage in cyberspace. For example, Cyworld, Korea's number one community site shows distinctive superiority in the consumer evaluations of content characteristics such as content superiority, site vividness, and customerization. Particularly, comsumer evaluation about customerization was remarkably higher than the other sites. In this point, we can conclude that providing comsumers with good, unique and highly customized content will be urgent and important task directly and indirectly impacting to self congruency, consumer experience, c-to-c interactivity, and various loyalty factors of online community. By creating enjoyable, useful, and unique online community environments, online community portals such as Daum, Naver, and Cyworld are able to build customer loyalty to a degree that many of today's online marketer can only dream of these loyalty, in turn, generates strong economic returns. Another way to build good online community site is to provide consumers with an interactive, fun, experience-oriented or experiential Web site. Elements that can make a dot.com's Web site experiential include graphics, 3-D images, animation, video and audio capabilities. In addition, chat rooms and real-time customer service applications (which link site visitors directly to other visitors, or with company support personnel, respectively) are also being used to make web sites more interactive. Researchers note that online communities are increasingly incorporating such applications in their Web sites, in order to make consumers' online shopping experience more similar to that of an offline store. That is, if consumers are able to experience sensory stimulation (e.g. via 3-D images and audio sound), interact with other consumers (e.g., via chat rooms), and interact with sales or support people (e.g. via a real-time chat interface or e-mail), then they are likely to have a more positive dot.com experience, and develop a more positive image toward the online company itself). Analysts caution, however, that, while high quality graphics, animation and the like may create a fun experience for consumers, when heavily used, they can slow site navigation, resulting in frustrated consumers, who may never return to a site. Consequently, some analysts suggest that, at least with current technology, the rule-of-thumb is that less is more. That is, while graphics etc. can draw consumers to a site, they should be kept to a minimum, so as not to impact negatively on consumers' overall site experience.

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The Changes of System Design Premises and the Structural Reforms of Korean Government S&T Development Management System (시스템 설계전제의 변화와 공공부문 과학기술발전관리시스템 구조의 개혁)

  • 노화준
    • Journal of Technology Innovation
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    • v.5 no.2
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    • pp.1-21
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    • 1997
  • The objective of this paper is to think about what structural reforms of the Korean government S&T development management system might be. Korean society is currently experiencing a drastic socio-economic transformation. The results of this transformation should be reflected on the determining process of the directions and breadths of structural reforms of government S&T development management system. Because the government system design will be based on the premises of socio-economic conditions under which administrative activities perform and also this socio-economic changes can influence on changes of the premises of government management system design. Moreover, S&T development management system is a subsystem of government system so that the directions of structural reform of those subsystems should be considered in the broad framework changes in the development management system of the government. For the last forty years, the Korean government S&T development management system has been based on the premises including transformation from an agrarian society to an industrial society, authoritarianism and centrally controlled institutions, and exteremely small portions of private investments for science and thechonology R & D of the total. Recently, however, the premises of Korean government S&T development management system have rapidly changed. the characteristics of these changes are including tranformation from an industrial society to a knowledge and information intensive society, globalization, localization, and relatively large portion of private investments for science and technology R & C of the total. The basis of government reforms in Korea was the realization of the performances and values through the enhancement of national competitive capacity, attainment of lean government, decentralization and autonomy. However, the Korean government has attached a symbolic value of strategic organizations representing strong policy intentions of government for the science and technology based development. Most problems associated with the Korean government S&T development management system have grown worse during 1990s. Many people perceive that considerable part of this problem was generated because the government could not properly adapt itself to new administrative environment and the paradigm shift in its role. First of all, the Korean government S&T development management system as a whole failed to develop an integrated vision under which processes in formulating science and thechology development goals and developing consistent government plans concerning science and technology development are guided. Second, most of the local governments have little organizational capacity and manpowers to handle localized activities to promote science and technology in their regions. Third, the measure to coordinate and set priorities to invest resources for the development of science and technology was not effective. Fourth, the Most has been losing its reputation as the symbol of ideological commitment of the top policy maker to promote science and technology. Various ideas to reform government S&T development management system have been suggested recently. Most frequently cited ideas are as follow : (ⅰ)strengthen the functions of MoST by supplementing the strong incentive and regulatory measures; (ⅱ)create a new Ministry of Education, Science & Technology and Research by merging the Ministry of Education and the MoST; (ⅲ)create a new Ministry of Science & Technology and Industry ; and(ⅳ)create a National Science and Technology Policy Council under the chairmanship of the President. Four alternatives suggested have been widely discussed among the interested parties and they each have merits as well as weaknesses. The first alternative could be seen as an alternative which cannot resolve current conflicts among various ministries concerning priority setting and resource allocation. However, this alternatives can be seen as a way of showing the top policymaker's strong intention to emphasize science and technology based development. Second alternative is giving a strategic to emphasize on the training and supplying qualified manpower to meet knowledge and information intensive future society. This alternative is considered to be consistent with the new administrative paradigm emphasizing lean government and decentralization. However, opponents are worrying about the linkages and cooperative research between university and industry could be weakening. The third alternative has been adopted mostly in nations which have strong basic science research but weak industrial innovation traditions. Main weakness of this alternative for Korea is that Korean science and technology development system has no strong basic science and technology research traditions. The fourth alternative is consistent with new administrative paradigms and government reform bases. However, opponents to this alternative are worried that the intensive development of science and technology because of Korea's low potential research capabilities in science and technology development. Considerning the present Korean socio-economic situation which demands highly qualified human resources and development strategies which emphasizes the accumulations of knowledge-based stocks, I would like to suggest the route of creating a new Ministry of Education, Science & Technology and Research by intergrating education administration functions and science & technology development function into one ministry.

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Comparison Study of Water Tension and Content Characteristics in Differently Textured Soils under Automatic Drip Irrigation (자동점적관수에 의한 토성별 수분함량 및 장력 변화특성 비교 연구)

  • Kim, Hak-Jin;Ahn, Sung-Wuk;Han, Kyung-Hwa;Choi, Jin-Yong;Chung, Sun-Ok;Roh, Mi-Young;Hur, Seung-Oh
    • Journal of Bio-Environment Control
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    • v.22 no.4
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    • pp.341-348
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    • 2013
  • Maintenance of adequate soil tension or content during the period of crop growth is necessary to support optimum plant growth and yields. A better understanding of soil tension and content for precision irrigation would allow optimal soil water condition to crops and minimize the adverse effects of water stress on crop growth and development. This research reports on a comparison of soil water tension and content variations in differently textured soils over time under drip irrigation using two different water management methods, i.e. pulse time and required water irrigation methods. The pulse time-based irrigation was performed by turning the solenoid valve on and off for preset times to allow the wetting front to disperse in root zone before additional water was applied. The required water estimation method was a new water control logic designed by Rural Development Administration that applies the amount of water required based on a conversion of the measured water tension into water content. The use of the pulse time irrigation method under drip irrigation at a high tension of -20 kPa and high temperatures over $30^{\circ}C$ was not successful at maintaining moisture tensions within an appropriate range of 5 kPa because the preset irrigation times used for water control could not compensate for the change in evapotranspiration during day and night. The response time and pattern of water contents for all of the tested soils measured with capacitance-based sensor probes were faster and more direct than those of water tensions measured with porous and ceramic cup-based tensiometers when water was applied, indicating water content would be a better control variable for automatic irrigation. The required water estimation-based irrigation method provided relatively stable control of moisture tension, even though somewhat lower tension values were obtained as compared to the target tension of -20 kPa, indicating that growers could expect to be effective in controlling low tensions ranging from -10 to -20 kPa with the required water estimation system.

Effects of Artificial Light Sources on the Photosynthesis, Growth and Phytochemical Contents of Butterhead Lettuce (Lactuca sativa L.) in the Plant Factory (식물공장에서 인공광원의 종류가 반결구상추의 광합성, 생육 및 기능성물질 함량에 미치는 영향)

  • Kim, Dong Eok;Lee, Hye Jin;Kang, Dong Hyeon;Lee, Gong In;Kim, You Ho
    • Journal of Bio-Environment Control
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    • v.22 no.4
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    • pp.392-399
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    • 2013
  • This study aimed to investigate responses of photosynthesis, plant growth, and phytochemical contents to different artificial light sources for 'Seneca RZ' and 'Gaugin RZ' two butterhead lettuce (Lactuca sativa L.). In this study, fluorescent lamps (FL), three colors LEDs (red, blue and white, 5 : 4 : 1; RBW) and metalhalide lamps (MH) were used as artificial lighting sources. Photoperiod, air temperature, relative humidity, EC, and pH in a cultivation system were maintained at 16/8 h, $25/15^{\circ}C$, 60~70%, $1.4{\pm}0.2dS{\cdot}m^{-1}$, and $6.0{\pm}0.5$, respectively. The photosynthetic rate of both two butterhead lettuce were the highest under RBW in middle growth stage. However, in late growth stage, the photosynthetic rate of both two butterhead lettuce were higher under RBW and MH than FL. The light sources showed significant results for plant growth but those effects were different to variety. Fresh and dry weight of 'Gaugin RZ' butterhead lettuce under MH were heavier than other lights in all growth stages. Growth of 'Seneca RZ' butterhead lettuce was maximized highest under MH in middle growth stage and FL in late growth stage. In the leaf tissue of 'Seneca RZ' butterhead lettuce, tipburn symptom occurred under all light sources and in the leaf tissue of 'Gaugin RZ' butterhead lettuce, it occurred under two light sources except for fluorescent lamps in late growth stage. kinds of lamp affect plant growth more than plant quality. Relative growth rate of both two butterhead lettuce was faster in middle growth stage than late stage. Growth of 'Gaugin RZ' was shown by kinds of lamp in middle growth stage and but it was not significantly affected by light sources and variety in late stage. Most of the phytochemical contents of two butterhead lettuce were significantly affected by different light sources. Contents of all vitamins showed higher than other light sources on RBW for both two lettuce, especially ${\beta}$-Carotene content of 'Gaugin RZ' was the highest. Plant growth, photosynthesis, and phytochemical contents were observed significant effects by different light sources for two butterhead lettuce but those effects were highly different between variety and kinds of phytochemicals. Therefore, the selection of optimum light source should be considered by variety and kinds of phytochemicals in the plant factory.

Spatially-resolved Photoluminescence Studies on Intermixing Effect of InGaAs Quantum Dot Structures Formed by AlAs Wet Oxidation and Thermal Annealing (AlAs 습식산화와 열처리로 인한 InGaAs 양자점 레이저 구조의 Intermixing효과에 관한 공간 분해 광학적 특성)

  • Hwang J.S.;Kwon B.J.;Kwack H.S.;Choi J.W.;Choi Y.H.;Cho N.K.;Cheon H.S.;Cho W.C.;Song J.D.;Choi W.J.;Lee J.I.
    • Journal of the Korean Vacuum Society
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    • v.15 no.2
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    • pp.201-208
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    • 2006
  • Optical characteristics of InGaAs quantum dot (QD) laser structures with an Al native oxide (AlOx) layer as a current-blocking layer were studied by means of photoluminescence (PL), PL excitation, and spatially-resolved micro-PL techniques. The InGaAs QD samples were first grown by molecular-beam epitaxy (MBE), and then prepared by wet oxidation and thermal annealing techniques. For the InGaAs QD structures treated by the wet oxidation and thermal annealing processes, a broad PL emission due to the intermixing effect of the AlOx layer was observed at PL emission energy higher than that of the non-intermixed region. We observed a dominant InGaAs QD emission at about 1.1 eV in the non-oxide AlAs region, while InGaAs QD-related emissions at about 1.16 eV and $1.18{\sim}1.20eV$ were observed for the AlOx and the SiNx regions, respectively. We conclude that the intermixing effect of the InGaAs QD region under an AlOx layer is stronger than that of the InGaAs QD region under a non-oxided AlAs layer.

Relationship between Monounsaturated Fatty Acid Composition and Stearoyl-CoA Desaturase mRNA Level in Hanwoo Liver and Loin Muscle (한우 간 및 등심 조직에서 불포화지방산의 조성비율과 Stearoyl-CoA Desaturase mRNA의 발현 양상)

  • Lee, S.H.;Yoon, D.H.;Hwang, S.H.;Cheong, E.Y.;Kim, O.H.;Lee, C.S.
    • Journal of Animal Science and Technology
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    • v.46 no.1
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    • pp.7-14
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    • 2004
  • The Stearoyl-CoA Desaturase(SCD) is a key enzyme, which converting palmitic acid(16:0) and stearic acid (18:0) to pahnitoleic acid(16:1) and oleic acid(l8:1), respectively. The concentration of oleic acid(18:1) in meat of beef cattle could influence both palatability and perception of meat. This experiment has conducted to determine relationship between the compositions of monounsaturated fatty acids and the SCD mRNA level in bovine liver and loin muscle tissue. The compositions of palmitoleic acid(16:1) and oleic acid(18:1) in loin muscle were 5% and 46% of total lipid and in liver were 2% and 20% of total lipid, respectively. On the other hand, the compositions of palmitic acid(16:0) and stearic acid(18:0) in loin muscle were 25% and 45% of total lipid and in liver were 14% and 43% of total lipid, respectively. The ratio of monounsaturated to saturated fatty acids(the desaturation index) was used as a measure of SCD activity in tissues. The average desaturation index in loin muscle was higher about 3.6-fold than that in liver. The desaturation index of oleate/stearate and palmitoleatelpalmitate in loin muscle were higher 8-fold and 1.8-fold than those in liver, respectively, showing that the substrate specificity of SCD enzyme was very different between liver and muscle tissues. To determine whether the composition of monounsaturated fatty acids in liver and muscle are dependent on SCD expression, SCD mRNA level was examined by RT-PCR analysis. The SCD mRNA level in loin muscle was higher about 3-fold than that in liver. Thus, the quantitative relationship between the desaturation index of fatty acid and SCD mRNA was observed in liver and muscle. The difference in the compositions of monounsaturated fatty acids between bovine liver and muscle tissues may be due to different level of Stearoyl-CoA Desaturase mRNA.