• Title/Summary/Keyword: free play

Search Result 705, Processing Time 0.034 seconds

Comparison of Filtering Abilities of Korean Freshwater Bivalves and Their Filtering Effects on Water Quality (국내 담수산 조개의 섭식활동이 호수 수질에 미치는 영향)

  • Kim, Ho-Sub;Choi, Kwang-Hyun;Park, Jung-Hwan;Shin, Jae-Ki;Hwang, Soon-Jin
    • Korean Journal of Ecology and Environment
    • /
    • v.35 no.2 s.98
    • /
    • pp.92-102
    • /
    • 2002
  • This study was conducted to compare filtering abilities of three species of freshwater mussels (Cobicula fluminea, Corbicula leana and Unio douglasiae) and to evaluate their filter feeding effects on water quality change in experimental enclosure systems. Mussel feeding in both laboratory and enclosure resulted in decrease of particulate material, such as chlorophyll, total P, SS. In the treatment with 600 individuals of mussels, chllorophyll concentration and net primary productivity decreased from $87.3{\pm}4.5\;{\mu}g/L$ and $106.3{\pm}8.8\;{\mu}gC\;L^{-1}\;hr^{-1}$ to nearly the same level as the mussel-free enclosure ($25.0{\pm}0.5\;{\mu}g/L$ and $15.6{\pm}13.3\;{\mu}gC\;L^{-1}\;hr^{-1}$, respectively)(P< 0.05, n = 6, ANOVA). In concert with the decrease of chlorophyll concentration, not only was the transparency enhanced from 0.48 m to 1.2m but also the suspended solids and total phosphorus decreased from $22.0{\pm}1.0\;mg/L$ to $7.5{\pm}0.5\;mg/L$ and $133{\pm}0.8\;{\mu}g/L$ to $70{\pm}0.0\;{\mu}g/L$, respectively (P<0.001, $r^2$>0.71, n = 11). Although slight decrease of SRP concentration and the increase of inorganic nitrogen ($NH_3-N$ and $NO_2-N$) were observed in the mussel addition enclosure, there was no statistical difference between two enclosures. Based on the filtering rate on phytoplankton and nutrient release rate in forms of feces and pseudofeces, Corbicula leana appeared to be the most efficient filter-feeder among three mussel species. These results inidicate that Cobicula play an important role in controlling particulate sestons and thus it could be applied as a biocontroler for the water quality management in lakes and reservoirs with algal blooms.

Beginning of the Meteorological Satellite: The First Meteorological Satellite TIROS (기상위성의 태동: 최초의 기상위성 TIROS)

  • Ahn, Myoung-Hwan
    • Atmosphere
    • /
    • v.22 no.4
    • /
    • pp.489-497
    • /
    • 2012
  • Recently released a top secret document explicitly shows that the early development plan for an earth observation satellite in the USA has a hidden and more important purpose for a concept of 'free space' than the scientific purpose. At that time, the hidden and secret concept imbedded within the early space development plan prevail other national policies of the USA government for purpose of the national security. Under these circumstances, it is quite reasonable to accept a possibility that the meteorological satellites which play a key role in the every area of meteorology and climatology was also born for the hidden purposes. Even it is so, it is quite amazing that the first meteorological satellite is launched in the USA despite of the facts that the major users of the meteorological satellites were not very enthusiastic with the meteorological satellite and the program was not started as a formal meteorological satellite project. This was only possible because of the external socio-political impact caused by the successful launch of the Russian Sputnik satellite and a few key policy developers who favored the meteorological satellite program. It is also interesting to note that the beginning of the first Korean meteorological satellite program was initiated by a similar socio-political influence occurred by the launch of a North Korean satellite.

Effect of Dietary Supplementation of Vitamin A and Chronic Consumption of Ethanol on Oxidative Damage and Antioxidant System in Rats (비타민 A 보충 식이 및 에탄올의 만성적 급여가 흰쥐의 체내 산화적 손상과 항산화체계에 미치는 영향)

  • 양경미
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.32 no.2
    • /
    • pp.278-286
    • /
    • 2003
  • Alcohol is well known agent which can damage the human tissues such as liver via stimulating lipid peroxidation. On the other hand, carotenoids in addition to vitamins A, C and I play important roles in protecting these oxidative damages as well as preventing the production of free radicals. This study was carried out to investigate the effect of dietary vitamin A on lipid peroxidation and antioxidants status in ethanol-treated rats. In the experiment, male Sprague-Dawley rats weighing 160~180 g were given a liquid diet containing 36% of total calories as ethanol for 7 weeks. The pair-fed control rats received an isocaloric amount of diet containing sucrose instead of ethanol on the following day Additionally, the liquid diet contained adequate amount of $\beta$-carotene, retinyl acetate or 13-sis-reinoic acid except vitamin A-deficient diet. The results obtained are as follows. The levels of plasma and hepatic lipid peroxide were increased after chronic ethanol feeding in rats. Retinyl acetate supplementation significantly reduced lipid peroxidation induced by ethanol feeding Glucose 6-phosphatase activity was significantly reduced in rats fed vitamin A-deficient diet with ethanol and alkaline phosphatase activity was significantly induced in rats fed 13-cis-reinoic acid diet with ethanol. Catalase and alcohol dehydrogenase activities did not show a consistent tendency in experiment groups. The hepatic antioxidant enzyme activities did not significantly changed by chronic ethanol feeding groups. The striking decrease in conversion of $\beta$-carotene to retinol was observed in rats fed a $\beta$-carotene diet with ethanol feeding The level of retinol and retinoic acid in plasma and liver was decreased after chronic ethanol administration Based on this result, these data suggest that ethanol feeding enhances oxidative stress especially in those fed a vitamin A-deficient diet, and vitamin A supplementation, especially, retinyl acetate intake can prevent enhanced lipid peroxidation and related damage to some extent.

Nerve Growth Factor and Sensory Neuropeptide Levels in Plasma and Saliva of Various Orofacial Pain Patients (다양한 구강안면통증환자의 혈장 및 타액에서의 신경성장인자와 감각성 신경펩티드 농도에 관한 연구)

  • Jang, Min-Uk;Chung, Sung-Chang;Chung, Jin-Woo
    • Journal of Oral Medicine and Pain
    • /
    • v.34 no.4
    • /
    • pp.387-395
    • /
    • 2009
  • Nerve growth factor (NGF) and sensory neuropeptides are involved in the process of nociception at peripheral nerve fibers and wide spread in central nervous system. The aims of this study were to investigate NGF and sensory neuropeptides (substance P [SP] and calcitonin gene-related peptide [CGRP]) levels in human plasma and saliva, and the associations between these sensory neuropeptides levels and chronic orofacial pain symptoms. NGF, SP, and CGRP levels in plasma and resting whole saliva samples collected from 67 orofacial pain patients (joint pain, dental or periodontal pain, mucosal pain) and 36 pain free control subjects were measured by enzyme immunoassay. The characteristic pain intensity of each subject was measured using the Graded Chronic Pain Scale and the flow rate of resting whole saliva was measured. Joint pain patients group showed significantly higher plasma NGF level compared to each of dental pain patients (p<0.01), mucosal pain patients (p<0.01), and control group (p<0.01). Plasma NGF level of dental pain patients group was significantly higher than that of control group (p<0.01). Saliva SP level of dental pain patients group (p<0.05) and saliva CGRP level of mucosal pain group (p<0.05) were significantly higher than that of control group. Plasma and saliva SP levels of joint pain patients was significantly associated with pain intensity (plasma: standardized coefficient=0.599, p<0.01, saliva: standardized coefficient=0.504, p=0.05). In dental pain patients group, plasma SP (standardized coefficient=0.559, p<0.01), saliva SP (standardized coefficient=0.520, p<0.01) and saliva CGRP (standardized coefficient=0.599, p<0.01) levels were significantly associated with age. In mucosal pain patients group, plasma SP (standardized coefficient=0.495, p<0.05), saliva SP (standardized coefficient=0.500, p<0.05), and saliva CGRP (standardized coefficient=0.717, p<0.01) levels were significantly associated with age. NGF and neuropeptides may play a role in the maintenance of various orofacial pain symptoms. The examination of those levels in plasma and saliva helps understanding the mechanism of orofacial pain, and furthermore, can be applied to the diagnosis and therapy of orofacial pain.

Superoxide Dismutase Gene Expression in the Endotoxin-Treated Rat Lung (내독소에 의한 백서 폐장의 Superoxide Dismutase 유전자 발현에 관한 연구)

  • Yoo, Chul-Gyu;Suh, Gee-Young;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo;Kim, Keun-Youl;Han, Yong-Chol
    • Tuberculosis and Respiratory Diseases
    • /
    • v.41 no.3
    • /
    • pp.215-221
    • /
    • 1994
  • Background: It is well known that oxygen free radicals(OFR) play a vital role in the various type of acute lung injury. Among various antioxidant defense mechanisms, the superoxide dismutases(SOD) are thought to be the first line of antioxidant defense by catalyzing the dismutation of two superoxide radicals to yield hydrogen peroxide and oxygen. Eukaryotic cells contain two types of intracellular SOD : cytosolic, dimeric copper/zinc- containing enzyme(CuZnSOD) and mitochondrial, tetrameric manganese-containing enzyme(MnSOD). The purpose of this study is to evaluate the time-dependent gene expression of MnSOD and CuZnSOD in the endotoxin-treated rats, and to compare with the manifestations of LPS-induced acute lung injury in rats. Methods: Total RNA from rat lung was isolated using single step phenol extraction 0, 1, 2, 4, 6, 12, 18, 24 hours after E. coli endotoxin injection(n=3, respectively). RNA was separated by formaldehyde-containing 1.2% agarose gels elctrophoresis, transblotted, baked, prehybridized, and hybridized with $^{32}P$-labeled cDNA probes for rat MnSOD and CuZnSOD, which were kindly donated by Dr. Ho(Duke University, Durham, NC, USA). The probes were labeled by nick translation. Blots were washed and autoradiography were quantitated using laser densitometry. Equivalent amounts of total RNA/gel were assessed by monitoring 28S and 18S rRNA. Results: Endotoxin caused a rise in steady-state MnSOD mRNA levels by 4h with peak mRNA accumulation by 6h. Continued MnSOD mRNA expression was observed at 12h. CuZnSOD mRNA expression was observed from 1h to 24h with peak levels by 18h. Conclusion: These results suggest that SOD palys an important defensive role in the endotoxin-induced acute lung injury in rats.

  • PDF

The Effects of Virtual Reality Advertisement on Consumer's Intention to Purchase: Focused on Rational and Emotional Responses (가상현실(Virtual Reality) 광고가 소비자 구매의도에 미치는 영향: 이성적인 반응과 감성적인 반응의 통합)

  • Cha, Jae-Yol;Im, Kun-Shin
    • Asia pacific journal of information systems
    • /
    • v.19 no.4
    • /
    • pp.101-124
    • /
    • 2009
  • According to Wikipedia, virtual reality (VR) is defined as a technology that allows a user to interact with a computer-simulated environment. Due to a rapid growth in information technology (IT), the cost of virtual reality has been decreasing while the utility of virtual reality advertisements has dramatically increased. Nevertheless, only a few studies have investigated the effects of virtual reality advertisement on consumer behaviors. Therefore, the objective of this study is to empirically examine the effects of virtual reality advertisement. Compared to traditional online advertisements, virtual reality advertisement enables consumers to experience products realistically over the Internet by providing high media richness, interactivity, and telepresence (Suh and Lee, 2005). Advertisements with high media richness facilitate consumers' understanding of advertised products by providing them with a large amount and a high variety of information on the products. Interactivity also provides consumers with a high level of control over the computer-simulated environment in terms of their abilities to adjust the information according to their individual interests and concerns and to be active rather than passive in their engagement with the information (Pimentel and Teixera, 1994). Through high media richness and interactivity, virtual reality advertisements can generate compelling feelings of "telepresence" (Suh and Lee, 2005). Telepresence is a sense of being there in an environment by means of a communication medium (Steuer, 1992). Virtual reality advertisements enable consumers to create a perceptual illusion of being present and highly engaged in a simulated environment, while they are in reality physically present in another place (Biocca, 1997). Based on the characteristics of virtual reality advertisements, a research model has been proposed to explain consumer responses to the virtual reality advertisements. The proposed model includes two dimensions of consumer responses. One dimension is consumers' rational response, which is based on the Information Processing Theory. Based on the Information Processing Theory, product knowledge and perceived risk are selected as antecedents of intention to purchase. The other dimension is emotional response of consumers, which is based on the Attitude-Structure Theory. Based on the Attitude-Structure Theory, arousal, flow, and positive affect are selected as antecedents of intention to purchase. Because it has been criticized to have investigated only one of the two dimensions of consumer response in prior studies, our research model has been built so as to incorporate both dimensions. Based on the Attitude-Structure Theory, we hypothesized the path of consumers' emotional responses to a virtual reality advertisement: (H1) Arousal by the virtual reality advertisement increases flow; (H2) Flow increases positive affect; and (H3) Positive affect increases intension to purchase. In addition, we hypothesized the path of consumers' rational responses to the virtual reality advertisement based on the Information Processing Theory: (H4) Increased product knowledge through the virtual reality advertisement decreases perceived risk; and (H5) Perceived risk decreases intension to purchase. Based on literature of flow, we additionally hypothesized the relationship between flow and product knowledge: (H6) Flow increases product knowledge. To test the hypotheses, we conducted a free simulation experiment [Fromkin and Streufert, 1976] with 300 people. Subjects were asked to use the virtual reality advertisement of a cellular phone on the Internet and then answer questions about the variables. To check whether subjects fully experienced the virtual reality advertisement, they were asked to answer a quiz about the virtual reality advertisement itself. Responses of 26 subjects were dropped because of their incomplete answers. Responses of 274 subjects were used to test the hypotheses. It was found that all of six hypotheses are accepted. In addition, we found that consumers' emotional response has stronger impact on their intention to purchase than their rational response does. This study sheds much light into practical implications for both IS researchers and managers. First of all, while most of previous research has analyzed only one of the customers' rational and emotional responses, we theoretically incorporated and empirically examined both of the two sides. Second, we empirically showed that mediators such as arousal, flow, positive affect, product knowledge, and perceived risk play an important role between virtual reality advertisement and customer's intention to purchase. In addition, the findings of this study can provide a basis of practical strategies for managers. It was found that consumers' emotional response is stronger than their rational response. This result indicates that advertisements using virtual reality should focus on the emotional side, and that virtual reality can be served as an appropriate advertisement tool for fancy products that require their online advertisements to give an impetus to customers' emotion. Finally, even if this study examined the effects of virtual reality advertisement of cellular phone, its findings could be applied to other products that are suited for virtual experience. However, this research has some limitations. We were unable to control different kinds of consumers and different attributes of products on consumers' intention to purchase. It is, therefore, deemed important for future research to control the consumer and product types for more reliable results. In addition to the consumer and product attributes, other variables could affect consumers' intention to purchase. Thus, the future research needs to find ways t control other variables.

The Applicable Laws to International Intellectual Property License Contracts under the Rome I Regulation (국제 지식재산권 라이센스 계약 분쟁의 준거법 결정 원칙으로서 로마I 규정의 적용에 관한 연구)

  • Moon, Hwa-Kyung
    • Journal of Legislation Research
    • /
    • no.44
    • /
    • pp.487-538
    • /
    • 2013
  • It is the most critical issue in recent international intellectual property licence disputes to decide the applicable laws to the license contracts. As Korea and the European Union(EU) reached free trade agreement(FTA), and the EU-Korea FTA entered into force on July 1, 2011, the FTA has boosted social, economic, cultural exchanges between the two. As a result of the increased transactions in those sectors, legal disputes are also expected to grow. This situation calls for extensive research and understanding of the choice of law principles applicable to international intellectual property license contracts in the EU. To decide the laws applicable to issues arising from international intellectual property license contracts disputes, the characterization of those issues is necessary for the purpose of applying private international law principles to them. In terms of characterization, intellectual property license contracts fall within contractual matters. In the EU, the primary rule of choice of law principles in contractual obligations is the Rome I Regulation. Because the choice of law rules, such as private international law principles, the Rome Convention(1980), and the Rome I Regulation, differ in the time of application, it is essential to clarify the time factor of related contracts. For example, the Rome I Regulation applies to contracts which were concluded as from December 17, 2009. Although party autonomy in international contracts disputes is generally allowed, if there is no choice of law agreement between the parties to the contracts, the objective test rule of private international law doctrine could be the best option. Following this doctrine, the Rome I Regulation Article 4, Paragraph 1 provides the governing law rules based on the types of contracts, but there is no room for intellectual property license contracts. After all, as the rule for governing law of those contracts, the Rome I Regulation Article 4, Paragraph 2 should be applied and if there are countries which are more closely connected to the contracts under the Rome I Regulation Article 4, Paragraph 3, the laws of those countries become the governing laws of the contracts. Nevertheless, if it is not possible to decide the applicable laws to the license contracts, the Rome I Regulation Article 4, Paragraph 4 should be applied in the last resort and the laws of the countries which are the most closely connected to the contracts govern the license contracts. Therefore, this research on the laws applicable to intellectual property license contracts under the Rome I Regulation suggests more systematic and effective solutions for future disputes in which Korea and the EU countries play the significant role as the connecting factors in the conflict of laws rules. Moreover, it helps to establish comprehensive and theoretical understanding of applying the Korean Private International Law to multifarious choice-of-law cases.

Study on Tragic Characteristic in Lope's Drama La estrella de Sevilla (로뻬의 연극 『세비야의 별』에 나타난 비극성 연구)

  • YOON, Yong-wook
    • Cross-Cultural Studies
    • /
    • v.50
    • /
    • pp.371-394
    • /
    • 2018
  • La estrella de Sevilla, is a representative masterpiece of the Golden Age of Spain, and is a tragic work of Lope de Vega, who was a representative drama writer living in the 17th century. However, regardless of its great literary value, there are insufficient researches on this drama even in Spain, due to several controversies surrounding the truth about Lope's creation. Here, this research concretely investigated the tragic characteristic of this drama, by largely dividing it into the viewpoint of Aristotle and Shakespeare. Thanks to the noble social status of the characters and proper dialogue of the hero Sancho Ortiz in trouble, there seems to be no problem in performing the cathartic function that Aristotle mentioned regarding the work in his review. However, there are a few problems in the aspect of the 'hero's free will to resist the absolute fate,' which is fundamentally the essence of the associated Aristotelian tragedy. Because, there's no Hamartia in this drama, the core mechanism that forms the absolute fate, makes the statement that accordingly, no absolute fate or irresistible force of destiny is established. Rather, the tragic characteristic of this drama can be more properly investigated from the viewpoint of Shakespeare. As noted differently from Aristotle, Shakespeare considered that the tragic characteristic came from the hero's characteristic. According to him, tragedy starts from the hero's value view and personality, instead of the external factors such as an absolute fate. Actually, Busto's death and separation between Sancho Ortiz and Estrella, two tragic affairs of La estrella de Sevilla, were caused by the crooked selfishness of King Sancho IV, who abused his authority, and Sancho Ortiz' excessively blind loyalty to the King, rather than the irresistible event. In conclusion, in light of a lethargic and hopeless situation, with no eventual choice of options before the injustice of absolute power, is must have been a significant tragedy for the audience, witnessing the play's tragic ending.

A Study on Usability of Open Source Software for Developing Records System : A Case of ICA AtoM (공개 소프트웨어를 이용한 기록시스템 구축가능성 연구 ICA AtoM을 중심으로)

  • Lee, Bo-Ram;Hwang, Jin-Hyun;Park, Min-Yung;Kim, Hyung-Hee;Choi, Dong-Woon;Choi, Yun-Jin;Yim, Jin-Hee
    • The Korean Journal of Archival Studies
    • /
    • no.39
    • /
    • pp.193-228
    • /
    • 2014
  • In recent years, as well as management of public records, interest in the private archive of large and small is growing. Dedicated archive has various types. In addition, lack of personnel and budget, personnel records management professional because the absence, that help you maintain these records in a systematic manner is not easy. Request to the system have continued to rise, but the budget and professionals in order to solve this problem are missing. As breakthrough of the burden to the system with archive dedicated, it introduces the trends and meaning of public recording system, and was examined in detail AtoM function. AtoM is public land can be made by a method that requires a Web service, the database server. Without restrictions, including the advantage of being available free of charge, by the application or operating system specific, installation and operation is convenient. In addition, compatibility, and is highly scalable, AtoM use and convenient archive of private experiencing a shortage of personnel and budget. Because in terms of data management, and excellent interoperability and search share, and use, it is possible in the future, it favors also documentary use through a network of inter-agency archives and private. In addition, Enhancements exhibition services through cooperation with Omeka, long-term storage through Archivematica, many discussion is needed. Public centered around the private area of the recording management spilling expanded, open-source software allows to balance the recording system will be able to play an important role. In addition, the efforts of academia and in the field, close collaboration between the open source recording system through a user study should be continued. Furthermore, co-operation and sharing of private archives expect come true.

The Direction of Physical Training for Actor in Post-Drama Era, "Empty" (포스트드라마 시대에 따른 배우의 몸 훈련의 방향성,'비우기(empty)')

  • Ra, Kyung-Min
    • Journal of Korea Entertainment Industry Association
    • /
    • v.14 no.8
    • /
    • pp.77-90
    • /
    • 2020
  • Today, the transition to the era of "post-drama" brought a change in the position of text, which was considered the center of the play, and the expansion of the role of actors. After entering the post-drama era, the actor no longer transforms himself into "delivering" the fixed meaning of text, but "producing" the valid meaning of "now, here" meeting the audience. In other words, actors in the post-drama era have expanded their roles as "performers" who can become the subject of narratives themselves and create various theatrical languages. Despite the expansion of the actor's role, verbal-centered actor training through text, which still forms the basis of acting education, does not satisfy the newly changing contemporary theatricality and creates a gap between education and the field. Therefore, the researcher argued that non-verbal-centered acting education needs to be discussed, and highlighted the actors' physical training on the "empty" side. The researchers first compare and analyze the characteristics of modern theater people's training methods from an "empty" perspective. Based on this, researchers about the meaning and direction of the training "empty". Furthermore, the study concludes with an emphasis on the direction of acting education in the post-drama era, which is free from language that can respond to stimuli and interact freely.