• Journal of Life Science
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• v.31 no.4
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• pp.430-441
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• 2021

Sesquiterpene lactones (STLs) are terpenoids found mostly in the Asteraceae family and are known for their strong cytotoxic properties, among other notable bioactivities. Some STLs, such as artemisinin and mipsagargin, are already commercially available and are used to fight malaria and tumor growth, respectively. Although the interest in STLs was low for a time after their discovery due to their toxic nature, past decades have witnessed a soar in STL-based studies focused on developing novel pharmaceuticals via chemical diversification. These studies have reported several promising physiological effects for STLs, including lower toxicity and diverse modes of action, and have demonstrated the antimicrobial, antioxidant, hepatoprotective, antiviral, antiprotozoal, phytotoxic, antitumor, and antiaging properties of STLs. STLs are mainly considered as valuable natural molecules for the fight against cancer since most STLs induce death of different types of cancer cells, as shown by in vitro and in vivo studies. Some STLs can also enhance the effects of drugs that are already in clinical use. Medicinal chemists use various STLs as starting molecules for the synthesis of new STLs or different bioactive compounds. All these developments warrant future research to provide more information on STLs, their bioactivities, and their mode of action. In this context, this review has summarized the bioactivities of some of the widely studied STLs, namely artemisinin, costunolide, thapsigargin, arglabin, parthenolide, alantolactone, cynaropicrin, helenalin, and santonin.

• Journal of vocational education research
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• v.36 no.4
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• pp.79-102
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• 2017

The purpose of this study was to develop curriculum framework for entrepreneurship development for adolescents. In order to achieve this goal, we studied and developed entrepreneurship semantics, entrepreneurship education, entrepreneurship education, entrepreneurship education contents. This study was developed through Delphi survey. The results of this study were as follows. First, the meaning of entrepreneurship is Innovative mind-set to create true value by experience into life in order to pursue 'self full-filling life' as the organizer of life. Second, the nature of entrepreneurship education for youth is that entrepreneurship education aims to find and solve new problems through self-management to young people who will lead the future, and to create dynamic challenges and creative changes to create innovative values. Leadership skills, challenging spirit, and ability to solve practical problems'. Third, we developed a general goal for youth and elementary, middle and high school goal for entrepreneurship education. Fourth, as a domain of entrepreneurship education, we have developed 'core discovery', 'entrepreneurial skills', 'becoming an entrepreneur' and developed key themes. Based on the results of this study, we developed a systematic entrepreneurship education linkage and educational condition creation for young people outside schools; entrepreneurship program application and educational condition development according to the operation of the free-learning semester system; the strengthening of business start-up support for youth in late adolescence, the establishment of measures to utilize related institutions in local communities and others.

• Journal of Life Science
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• v.28 no.12
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• pp.1529-1535
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• 2018

The number of antibiotic-resistant bacteria is increasing rapidly while the discovery rate of new antibiotics is in decline. A systematic study is therefore necessary to investigate which bacteria are resistant to medically important antibiotics and how high that resistance is. To that end, this study aimed to analyze which bacteria demonstrated resistance to ampicillin, one of the currently most-widely used medical antibiotics. Water samples were collected from the Changwon-Cheon that runs through Changwon City and from the pond in front of the dormitory building at Changwon University. Hundreds of ampicillin-resistant colonies were obtained and 22 morphologically distinct examples were chosen for further study. These bacteria were identified by amplifying their 16S rRNA genes and comparing those sequences with data in GenBank. The bacteria was identified as belonging to 10 families, 12 genera, and 17 species, and all were able to grow in the presence of $50{\mu}g/ml$ ampicillin while seven showed growth at ampicillin concentrations as high as 1.5 mg/ml.

• English & American cultural studies
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• v.9 no.1
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• pp.273-295
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• 2009

As Oedipa Mass, the heroine of Thomas Pynchon's The Crying of Lot 49, is apparently associated with Oedipus, the hero in Sophocles' tragedy, this paper aims to show some of their similarities in quest theme and plot development as well as in the use of dramatic irony. Oedipus the King opens with a priest's pleas to relieve the Theban people from a plague and the king's promise to rid its cause by avenging the murder of the former king, as told by the oracle. Lot 49 begins as a Los Angeles law firm informs Oedipa that she is named as the executrix in her former lover Inverarity's will to sort out the mogul's estate. Ironically, however, Oedipus' investigation reveals himself to be the very cause of the national disaster, the murderer for whom he searched. Likewise, Oedipa starts her inquiry dedicating herself to make sense out of what Inverarity had left behind, only to find that the legacy was America. Sophocles and Pynchon both employ dramatic irony to provide a controlling principle for plot development in their works. In Oedipus the King, Sophocles creates mounting tension as well as distance between the reader's knowledge and the protagonist's ignorance, compressing the play's action into the moment that Oedipus discovers his real identity. For dramatic irony, however, Pynchon tends to work through authorial comments and utilize allegorical meanings of the characters' names, directing his novel at illuminating Oedipa's discovery of Inverarity's legacy as well as the meaning of Tristero, an underground postal service system. Unlike Oedipus the King that proceeds on a single line of action, Lot 49 develops in esoteric, multi-layered allusions and intricately-interrelated double strains involving Oedipa's roles as executrix and quester. At the end of Sophocles' tragedy, Oedipus stabs his eyes and decides to live in exile, realizing that, blinded, he begot his children through his mother; Oedipa comes to a painful realization that she allowed her former lover to create death-orienting America without her diversity and moral system in old times. As Oedipa now discovers herself through her search for Tristero, her tragic spirit lies in her determination to confront her binary choices between two Americas: transcendence or entropy, the Tristero possibility or Inverarity's America. Ultimately, Oedipa tries to find who will be the bidder for the Tristero forged stamps designated as lot 49, awaiting the auctioneer's cry and the "crying" of a new-born America.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.19 no.2
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• pp.63-74
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• 2009

In 2005, Wang et al. discovered devastating collision attacks on the main hash functions from the MD4 family. After the discovery of Wang, many analysis results on the security of existing hash-based cryptographic schemes are presented. At CRYPTO'07, Fouque, Leurent and Nguyen presented full key-recovery attacks on HMAC/NMAC-MD4 and NMAC-MD5[4]. Such attacks are based on collision attacks on the underlying hash function, and the most expensive stage is the recovery of the outer key. At EUROCRYPT'08, Wang, Ohta and Kunihiro presented improved outer key recovery attack on HMAC/NMAC-MD4, by using a new near collision path with a high probability[2]. This improves the complexity of the full key-recovery attack on HMAC/NMAC-MD4 which proposed by Fouque, Leurent and Nguyen at CRYPTO'07: The MAC queries decreases from $2^{88}$ to $2^{72}$, and the number of MD4 computations decreases from $2^{95}$ to $2^{77}$. In this paper, we propose improved outer key-recovery attack on HMAC/NMAC-MD4 with $2^{77.1246}$ MAC queries and $2^{37}$ MD4 computations, by using divide and conquer paradigm.

• Journal of Food Hygiene and Safety
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• v.35 no.6
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• pp.535-543
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• 2020

In addition to the ubiquitous roles of cellular RNA in genetic regulations, gene expression and phenotypic variations in response to environmental cues and chemotactic signals, the regulatory roles of a new type of RNA called extracellular RNAs (exRNAs) are an up-and-coming area of research interest. exRNA is transported outside the cell through membrane blebs known as membrane vesicles or extracellular vesicles (EVs). EV formation is predominant and conserved among all microbial forms, including prokaryotes, eukaryotes, and archaea. This review will focus on the three major topics concerning bacterially derived exRNAs, i.e., 1) the discovery of exRNA and influence of extraneous RNA over bacterial gene regulations, 2) the known secretion mechanism for the release of exRNA, and 3) the possible applications that can be devised with these exRNA secreted by different gram-negative and gram-positive bacteria. Further, this review will also provide an opinion on exRNA- and EV-derived applications such as the species-specific exRNA markers for diagnostics and the possible roles of exRNA in probiotics and the epigenetic regulations of the gut microbiome.

• Journal of The Korean Association For Science Education
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• v.42 no.2
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• pp.289-309
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• 2022

In recent years, astronomy has been snowballing: including Higgs particle discovery, black hole imaging, extraterrestrial exploration, and deep space observation. Students are also largely interested in astronomy. The purpose of this study is to discover what needs to be improved in the current astronomy curriculum in light of recent scientists' researches and discoveries. We collected keywords from all papers published from 2011 to 2020 in four selected journals-ApJ, ApJL, A&A, and MNRAS- by R package to examine research trends. The curriculum contents were extracted by synthesizing the in-service teachers' coding results in the 2015 revised curriculum document of six subjects (Science, Integrated Science, Earth Science I, Earth Science II, Physics II, Convergence Science). The research results are as follows: first, keywords that appear steadily in astronomy are 'galaxies: formation, galaxy: active, star: formation, accretion, method: numerical.' Second, astronomy curriculum includes all areas except the 'High Energy Astrophysical Phenomena' area within the common science curriculum learned by all students. Third, it is necessary to review the placement of content elements by subject and grade and to consider introducing new concepts based on astronomy research keywords. This is an exploratory study to compare curriculum and the field of scientific research that forms the basis of the subject. We expect to provide implications for a future revision of the astronomy curriculum as a primary ground investigation.

• Journal of Korea Entertainment Industry Association
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• v.15 no.4
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• pp.1-13
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• 2021

In this study, we tried to present suggestions to the Gyeongsangbuk-do tourism officials to satisfy them with experiential tourism resources and to revitalize their participation in the program. Therefore, the implications of this study are as follows. First, research on the satisfaction of experiential tourism programs and the willingness to participate in them is carried out, suggesting that it is a prerequisite for the transformation of the perception of tourists' participation in the Corona era. Second, it is necessary to make it a small experience tourist space that can provide non-face-to-face service utilizing the characteristics of contact technology, and to provide tourists with unique attractions against product discrimination and customer service. Third, through the introduction of non-face-to-face experience programs and expansion of services, the limited and macroscopic environment and social phenomenon of tourism activities in the Corona era, a new perception can be instilled. Fourth, visitors can expect to revitalize the tourism industry through the development and discovery of various programs. Thirdly, it will be possible to revitalize the local economy by giving meaning to the satisfaction of experiential tourism programs to tourists from all over the region's tourism business.

• The Journal of the Korea Contents Association
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• v.21 no.12
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• pp.66-75
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• 2021

The research is centered towards analyzing the usage status of YouTube platform and the nature of content supplied to YouTube by selecting Korean two Traffic Broadcastings Based on TBS(Traffic Broadcasting System) and TBN(Traffic Broadcasting Network). TBS operates 'Citizen's Broadcasting', which has 1.1 million subscribers among 13 YouTube channels, as its main channel. TBN has only 15,000 subscribers to its main 'TBN Tong', and YouTube channels in 12 local networks. TBS which has a dedicated YouTube manpower, is far ahead of TBN in terms of YouTube channel management and content composition. Both broadcasters are passive about creating new media content due to job stability. For the development of the YouTube platform for these two broadcasters, organizational changes within traffic broadcasting and changes in the perception of members are required, and live broadcasting and discovery of star creators are required. In the changing media environment two traffic broadcastings need a program distribution strategy that can be included in various media platforms.

• Journal of Korean Neurosurgical Society
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• v.65 no.5
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• pp.665-679
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• 2022

Objective : Patients with mild ischemic stroke experience various sequela and residual symptoms, such as anxious behavior and deficits in movement. Few approaches have been proved to be effective and safe therapeutic approaches for patients with mild ischemic stroke by acute stroke. Sildenafil (SIL), a phosphodiesterase-5 inhibitor (PDE5i), is a known remedy for neurodegenerative disorders and vascular dementia through its angiogenesis and neurogenesis effects. In this study, we investigated the efficacy of PDE5i in the emotional and behavioral abnormalities in rats with mild ischemic stroke. Methods : We divided the rats into four groups as follows (n=20, respectively) : group 1, naïve; group 2, middle cerebral artery occlusion (MCAo30); group 3, MCAo30+SIL-pre; and group 4, MCAo30+SIL-post. In the case of drug administration groups, single dose of PDE5i (sildenafil citrate, 20 mg/kg) was given at 30-minute before and after reperfusion of MCAo in rats. After surgery, we investigated and confirmed the therapeutic effect of sildenafil on histology, immunofluorescence, behavioral assays and neural oscillations. Results : Sildenafil alleviated a neuronal loss and reduced the infarction volume. And results of behavior task and immunofluorescence shown possibility that anti-inflammation process and improve motor deficits sildenafil treatment after mild ischemic stroke. Furthermore, sildenafil treatment attenuated the alteration of theta-frequency rhythm in the CA1 region of the hippocampus, a known neural oscillatory marker for anxiety disorder in rodents, induced by mild ischemic stroke. Conclusion : PDE5i as effective therapeutic agents for anxiety and movement disorders and provide robust preclinical evidence to support the development and use of PDE5i for the treatment of mild ischemic stroke residual disorders.