This study was carried out to investigate the protective effect of prednisolone in rabbit primary cultured articular chondrocytes treated with sodium nitroprusside (SNP), a nitric oxide donor. After a cell phenotype was determined, the MTT assay and Western blot analysis of type II collagen, cylooxygenase-2 (COX-2) and phosphorylated extracellular regulated kinase (pERK) were performed in the control, SNP (298 μg/ml) alone or SNP plus prednisolone (0.05-50 μg/ml)-treated rabbit articular chondrocytes. Immunofluorescence staining of type II collagen was also performed. Cell morphology indicated that SNP treatment induced cytotoxicity, and that the SNP-induced cytotoxicity was inhibited by prednisolone treatment. MTT assay showed that the SNP treatment resulted in a significant decrease in the level of cell viability compared with that of control (p<0.01), and that the prednisolone treatment resulted in a decrease in the SNP-induced cytotoxicity. SNP treatment resulted in a decrease in the level of type II collagen, compared with the control chondrocytes. The prednisolone treatment recovered the down-regulated expression of type II collagen induced by SNP, showing a significant level in 5 μg/ml of the prednisolone treatment group compared to the SNP treatment group (p<0.05). A significant increase in COX-2 was significantly induced by the SNP treatment compared to control chondrocytes (p<0.01). The COX-2 expression was decreased by the prednisolone treatment, showing a significant level in 50 μg/ml of the prednisolone treatment group compared to the SNP treatment group (p<0.05). These phenomena was confirmed by immunofluorescence staining. Furthermore, the SNP treatment significantly induced a decrease of pERK expression compared to the control chondrocytes (p<0.01). The prednisolone treatment recovered its expression, showing a significant level in 0.5 μg/ml of the prednisolone treatment group compared to the SNP treatment group (p<0.05). Taken the above results together, prednisolone is considered to inhibit SNP-induced cell death and dedifferentiation, and modulated expression of COX-2 and pERK in rabbit articular chondrocytes.
Effect of the nonuniform grid on the two-dimensional transport equation was investigated in terms of theoretical analysis and finite difference method (FDM). The nonuniform grid having a typical structure of the numerical weather forecast model was incorporated in the vertical direction, while the uniform grid was used in the zonal direction. The staggered and non-staggered grid were placed in the vertical and zonal direction, respectively. Time stepping was performed with the third-order Runge Kutta scheme. An error analysis of the spatial discretization on the nonuniform grid was carried out, which indicated that the combined effect of the nonuniform grid and advection velocity produced either numerical diffusion or numerical adverse-diffusion. An analytic function is used for the quantitative evaluation of the errors associated with the discretized transport equation. Numerical experiments with the non-uniformity of vertical grid were found to support the analysis.
Digital channels have been rising to the major shopping paths from the past few years, yet it is interesting to notice that more and more digital retailers advance into offline channel nowadays due to the benefits. For example, the digital retailing giant Amazon opened its first bricks-and-mortar bookstore in 2015. Dell, which distributes its products only in the catalog and digital channels, entered the leading retail stores such as Best Buy and Walmart. The digital retailers’ strategy trend that moves into the real world reveals the unique and powerful capabilities of the offline distribution channel and the importance of launching products in the offline channel. Previous studies in marketing have investigated various complement and substitute impacts of offline channel introduction (i.e., Avery et al. 2012, Wang and Goldfarb 2017). However, most of the literature focus on the pc-based online channel and catalog, there is little research about the impact of offline channel introduction on smartphone-based mobile channel. Although mobile channel is similar to online channel in many ways (i.e., internet access and convenient shopping), it can be distinguished from online channel in terms of search and access, leading to a different interplay with offline channel. This research, therefore, aims to investigate how product launching in offline channel affects purchases in mobile channel versus online channel, and deepen the understanding by exploring the moderating effect of offline store intensity. Besides, we also explore the interaction between two digital channels: online channel and mobile channel. As most of the multi-channel retailers offer products in both online and mobile channels, it is incremental to know the interplay between these two digital channels. Using data from a representative multichannel retailer selling beauty products, we find the following three empirical results. First, product introduction in offline channel has a positive effect on online and mobile sales, and the effect is greater for mobile. Second, as offline store increases, the positive impact of offline product launch weakens on online channel, and even turns to negative once the number of offline stores reaches a threshold. However, the influence on mobile channel stays the same. The results reflect that the complementary interplay between offline and mobile channel is relatively stronger than between online channel. Finally, within the digital channels, online purchases only increase with the growth of sales performance within online channel, whereas mobile purchases are positively affected by both within mobile channel sales and across online channel sales. Our findings contribute critical academic and managerial implications for multichannel retailing.
Marketing academics and practitioners have discerned the evolution in the prominence of digital, social media and mobile marketing based on technological innovations. Digital marketing has evolved over time from a specific marketing of products and services using digital channels to activities, institutions and processes facilitated by digital technologies. From an inclusive perspective, digital marketing refers to an adaptive, technology-enabled process by which firms collaborate with customers and partners to jointly create, communicate, deliver and sustain value for all stakeholders. Digital technologies allow the new adaptive process, institution and processes in marketing communication. The adaptive process creates value in new ways in new digital environments. Institutions build foundational capabilities to create such value jointly for their customers and for themselves. Processes create value through new customer experiences and through interactions among customers. The purpose of the assessment is to establish the current status of research evaluating digital marketing communication and to show how digital technology has shaped marketing communication evaluations. This study provides a broad disciplinary review of key cited works in digital marketing communication research and examines the effectiveness of various evaluation approaches, including new directions designed to capture meaningful insights and marketing communication value in digital marketing communication.
Customer engagement has become a prominent issue in hospitality and tourism industry. However, customer engagement, is not easily defined or uniformly measured because a number of diverse factors must be considered. While meeting planners are important customers to CVBs, their engagement with CVBs has rarely been studied. Therefore, the purpose of this study was to develop and test a model of meeting planners’ engagement in CVBs empirically. Survey data were collected from a variety of meeting planners, which resulted in 305 usable responses for data analysis. Two step analyses (measurement model and structural model) were implemented. In addition, the moderating effect of reputation and familiarity were examined among the paths of the constructs. The results showed that the hypotheses were supported while familiarity has less salient impact than reputation on customer engagement in the event industry.
Virtual reality refers to an immersive computer-generated, interactive, 3D environment that offers media richness and interactivity. VR provides high media richness verified by the sensory depth and breadth of an interface. The purpose of this study is to investigate the relationships among mindsets, VR experience, perceived interactivity, attitude and purchase. This study clarifies the concept of VR experience and enlightened the relationship between VR experience, perceived interactivity, attitude and purchase intention. The study clarifies technology-driven experience, especially VR experience that can be differentiated from direct and indirect experience. The study can be a starting point to identifying how new technology boosts experiences by reflecting types of VR experience including spatial experience, presence experience, sensory experience and behavioral experience .
Cannibalism is a widely observed phenomenon in the animal kingdom. However, it is rarely found among birds outside nests in the wild because it occurs irregularly and it is almost impossible to monitor animal behavior constantly. On 17 January 2017, this behavior was directly observed from a group of vultures feeding on a conspecific in a paddy field near Lake Geumho in Haenam-gun (34°35ʹ58.25ʺ N, 126°26ʹ57.64ʺ E). It was observed and recorded with the binoculars and a camera with a telephoto lens in a car approximately 20 m (or 60 m) away from the site. The observer approached the feeding site after the last vulture had finished feeding and flown away and found remains of a vulture, including body feathers, skull, sterna keel, and both legs. It was the first report of cannibalism in Cinereous vulture Aegypius monachus in its overwintering grounds. The remaining skeleton was very fleshy, and the surrounding grass was wet with the blood of vulture. No other traces of a mammal or bird that could have been the vultures’ prey were found. This report provides a detailed account of the events related to this rare observation and the causes that might have led to it.
Kang, Minjung. 2018. “Functions of I mean in American Talk Shows”. The Sociolinguistic Journal of Korea 26(2). 63~84. This paper aims to find out roles of the discourse marker I mean in American talk shows. Ten interviews from six talk shows were analyzed for the investigation and the results indicate that there are some unique functions of I mean which do not seem to be mentioned in early studies: counter-accounting and footing shift functions. This study suggests that the counter-accounting function of I mean can appear in utterance-initial position when the interviewee does not agree with what the interviewer has mentioned. Also, the interviewee can use I mean as a footing shift marker to switch stances from an informative one to an entertaining one (or vice versa). Since these two functions seem to be connected to the institutional settings and goals of talk shows, it is crucial to study functions of I mean in accordance with types of institutional talk.
This study was an attempt to explore how EFL college-level learners perceive flipped learning or flipped classroom approach which would be practiced with Content-Based Instruction (CBI) courses. As an effort to find a way for the CBI learners to be served more effectively in terms of earning content-knowledge and improving L2-using skills, the new approach of flipped learning has been tapped into first of all by looking into their expectations and concerns that they might have if the new approach would be employed in their CBI classroom. The analysis of the data provided by the 159 participants revealed that they did not show clear preference or strong negative attitude toward the new approach. While the young college-level learners appeared technology-savvy, they did not seem confident enough in the new approach mainly due to the on-line component of the flipped classroom approach, which would require more responsibility of their learning. The study also made suggestions on what should be considered if the new approach can be successfully implemented and help the learners earn better learning experience.
K-means algorithm is one of the most popular and widely used clustering method because it is easy to implement and very efficient. However, this method has the limitation to be used with fixed number of clusters because of only considering the intra-cluster distance to evaluate the data clustering solutions. Silhouette is useful and stable valid index to decide the data clustering solution with number of clusters to consider the intra and inter cluster distance for unsupervised data. However, this valid index has high computational burden because of considering quality measure for each data object. The objective of this paper is to propose the fast and simple speed-up method to overcome this limitation to use silhouette for the effective large-scale data clustering. In the first step, the proposed method calculates and saves the distance for each data once. In the second step, this distance matrix is used to calculate the relative distance rate (Vj) of each data j and this rate is used to choose the suitable number of clusters without much computation time. In the third step, the proposed efficient heuristic algorithm (Group search optimization, GSO, in this paper) can search the global optimum with saving computational capacity with good initial solutions using Vj probabilistically for the data clustering. The performance of our proposed method is validated to save significantly computation time against the original silhouette only using Ruspini, Iris, Wine and Breast cancer in UCI machine learning repository datasets by experiment and analysis. Especially, the performance of our proposed method is much better than previous method for the larger size of data.
As a fuel for ship propulsion, liquefied natural gas (LNG) is currently considered a proven and reasonable solution for meeting the IMO emission regulations, with gas engines for the LNG-fueled ship covering a broad range of power outputs. For an LNG-fueled ship, the LNG bunkering process is different from the HFO bunkering process, in the sense that the cryogenic liquid transfer generates a considerable amount of boil-off gas (BOG). This study investigated the effect of the temperature difference on boil-off gas (BOG) production during ship-to-ship (STS) LNG bunkering to the receiving tank of the LNG-fueled ship. A concept design was resumed for the cargo/fuel tanks in the LNG bunkering vessel and the receiving vessel, as well as for LNG handling systems. Subsequently, the storage tank capacities of the LNG were 4,500 m3 for the bunkering vessel and 700 m3 for the receiving vessel. Process dynamic simulations by Aspen HYSYS were performed under several bunkering scenarios, which demonstrated that the boil-off gas and resulting pressure buildup in the receiving vessel were mainly determined by the temperature difference between bunkering and the receiving tank, pressure of the receiving tank, and amount of remaining LNG.
고추는 한국에서 매우 중요한 양념 중 하나이다. 하지만 수입 고춧가루와 다진 양념(다대기)에 부과되는 관세율(45%/270%)의 차이로 인해, 다진 양념이 수입된 후, 건 조 및 분쇄 과정을 거쳐 고춧가루로 제작되고 있는 실정 이다. 본 연구에서는 종 특이 PCR 기술과 whole-genome amplification 방법을 접목하여 고춧가루(N=45) 및 다진 양 념(N=5) 제품의 사용원료(고추, 마늘, 양파, 파, 생강)를 분 석하였다. 모니터링 결과, 39개 고춧가루 제품은 표시사항 을 준수하였으며, 6개 고춧가루 및 5개 다진 양념 제품은 제조 기준을 충족시키지 못했다. 따라서 분석 제품의 22% 가 표시사항을 준수하지 못한 것으로 밝혀졌으며, 본 연구에 사용한 분석 방법은 고춧가루 제품에 사용된 원료 분석에 적합한 방법임을 입증하였다.
In recent decades, introduction of the alien plant pests into Korea was dramatically increased and the role of plant quarantine became more important than ever. At the same time, early detection of the introduced population of the alien pests is critical for protection of their spread. However, continuous monitoring for their distribution or spread has not been performed yet in Korea. Present monitoring systems in Korea is not unified but sectored according to three institutes. There are some limitations in managing human resources, executing budgets, and collecting information among them, resuling in delayed responses to the introduced alien pests. Our study focused on 1) constructing nation-wide continuous monitoring system, 2) developing a decision flow chart for evaluating risks, 3) performing the benefits and costs analysis. Continuous monitoring will clarify overall distribution of alien pests, support government’s quarantine negotiation, and enable early detection of alien pests. Furthermore, the system will provide scientific data management and early responses to invasion of alien pests.
Gryllus bimaculatus is one of many cricket species known as field crickets. Also known as the African or Mediterranean field cricket or as the two-spotted cricket, it can be discriminated from other Gryllus species by the two dot-like marks on the base of its wings. G.bimaculatus is a subtropical insect and widely distributed from Africa to south Asia. After into the country, The species are popular for use as a food source for insectivorous animals like spiders and reptiles kept as pets. In 2016, G.bimaculatus was approved as a general food ingredient by Korean Ministry of Food and Drug Safety. However, domestic research on G.bimaculatus is still in its study is beginning stages. G.bimaculatus is possible species to year-round rearing without storage condition. but The aim of the present study prepares for in case of problems such as breeding space, labor cost etc. In the laboratory condition at 28±2℃ and 50% relative humidity under 10h light, 12h dark photoperiod, Adult crickets oviposit at soaked flower foam for 24 hours. The experiment on the hatching of the eggs showed that eggs could be stocked at 16℃ for 10 days with 7 day pre-period after laying, representing 85% hatchability.
아메리카왕거저리의 사육기간을 단축과 기능성 향상을 위해 밀기울에 다양한 먹이를 보조사료로 공급하여 발륙기 간과 무게를 측정한 결과, 먹이종류별 아메리카왕거저리의 발육기간은 조단백질함량이 많은 배합사료와 밀기울에서 80.8일과 75.6일로 가장 짧았으며 버섯배지는 160일이상 소요되었으며 왕겨의 생충율은 85%로 가장 낮아 버섯폐배지 와 왕겨는 먹이원으로 적절하지 않았다. 보조 먹이원 선발을 위해 할맥, 압맥, 배추, 백련초, 파프리카, 개똥쑥을 20~80% 밀기울에 첨가한 결과 압맥과 할맥은 정상적으로 생장하지만 백련초, 개똥쑥 혼합에서는 접종 직후부터 죽은 개체들이 출현하여 생충율이 12.9%, 10.8%로 아주 낮게 나타났으며 배추와 파프리카도 24.2~38.8%로 낮아 보조사료로 적합하지 않았다. 들깨와 콩가루 역시 생충율이 높지 않아 1, 2차 시험결과 할맥, 압맥과 메밀이 보조사료로 적합하였다.
The citrus flatid planthopper Metcalfa pruinosa, a invasive species causes serious damages to field crops, including sweet persimmon, soybean, maize, especially ginseng (Panax ginseng C.A meyer). We selected six chemical pesticides and one environmental friendly pesticide made from the mixture of derris extracts, citronella oils, and cinnamon extracts in laboratory. These pesticides showed over 90% of control effect in open ginseng field. This study was carried out with the support of the cooperative research program for RDA (project No. PJ0124992018), Republic of Korea.
Moderately diverse, but very abundant trace fossils are found from the Late Pleistocene deposits of Jeju Island, Korea. Vertical I-, Y- and U-shaped domichnia of annelids or decapods are, over 2500, extremely abundant, 3D network domichnia of callianassids are, over 200, very abundant, and small sinuous trails of nematode repichnia are, over 50, abundant in number. Horizontal trails attributable to polychaete or worm-like animals are, less than 50, common, but horizontal spreiten burrows, fish traces and crab trackways are, less than 10, rare in occurrence. Of these trace fossils, Taenidium barretti, Undichna britannica and Undichna unisulca represent the first record from the Pleistocene in Asia. Psilonichnus upsilon is the second record in Asia. Crab trackways probably produced by underwater punting gait of sideway walking crabs may represent the first record in the world. In addition, diverse and very abundant footprints of more than 500 hominids, more than 200 birds and more than 1000 mammals are closely associated with these invertebrate trace fossils. Trace fossil assemblage integrated with sedimentary facies is interpreted to have been formed in the marginal marine foreshore to backshore environment corresponding to the Psilonichnus and Skolithos ichnofacies.
The purpose of this study was to investigate the effects of squat exercises with an upper limb resistance movement on the vastus medialis oblique, vastus lateralis, and gluteus maximus. This study recruited 16 healthy men. All subjects performed squat exercises with and without upper Limb resistance movements by using elastic tubing band. Electromyography (EMG) activity of the vastus medialis oblique, vastus lateralis, and gluteus maximus was recorded using a surface EMG system during these isometric squat exercises in both experimental conditions. The different muscle activation of the vastus medialis oblique, vastus lateralis, and gluteus maximus between the squat exercises with and without the upper limb resistance movement was analyzed using a paired t-test or Wilcoxon signed rank test. Our findings showed that the vastus medialis oblique, vastus medialis oblique/vastus lateralis ratio and gluteus maximus muscle activity was significantly increased during the squat exercise with upper limb resistance movements, as compared to the squat exercise without this component (p < .05). Based on our findings, the additional upper limb resistance movement may be a useful strategy to facilitate the vastus medialis oblique and gluteus maximus muscle activation during a squat exercise.
방울토마토의 수경재배 중 붕소+칼슘+규소 및 칼슘+규소의 복합 엽면시비가 수확 후 품질과 MAP 저장 중 저장성에 미치는 영향을 알아보고자 본 연구를 실시하였다. 엽면시비한 방울 토마토(‘Unicorn’)는 반숙 과상태에서 수확하여 산소투과성 필름으로 포장한 5oC, 11oC, 그리고 24oC에서 25일, 15일, 10일간 저장하였다. 붕소+칼슘+규소 복합처리한 방울토마토가 3가지 저장온도 모두에서 호흡과 에틸렌 발생이 억제되어 MAP 저장중 가장 낮은 생체중 감소와 가장 높은 외관상 품질을 보였다. 수확 후 조사한 방울토마토의 경도, 산도, 비타민 C 함량은 붕소+칼슘+규소 복합처리에서 가장 높았으며, 3가지 온도 모두에서 MAP 저장 후에도 모두 높게 유지되었다. 그러나 과피색, 라이코펜 함량과 당도는 수확 후에는 엽면시비 처리로 차이가 없었으나, 3가지 온도 모두 붕소+칼슘+규소 복합처리에서 가장 낮은 수치를 보였다. 이상의 결과로 볼 때 붕소+칼슘+규소 복합처리는 방울토마토의 수확후 생리 작용을 억제하고 경도, 산도, 비타민 C 함량을 높여 저장성을 향상시키는 것으로 판단되었다