• Journal of Korean Society on Water Environment
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• v.33 no.4
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• pp.449-459
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• 2017

In Geum River of Korea, three multi-purpose weirs were built at the downstream of Daecheong Reservoir during the Four Major River Restoration Project (FMRRP). The weirs have altered the hydraulic characteristics of the river, and consequently transformed the large areas of flowing ecosystem to deep and wide stagnant environment. In every summer, a thermal stratification occurred near the Baekje Weir having mean depth of 4.0 m, and the surface algal blooms dominated by buoyant cyanobacteria have been frequently formed after the FMRRP. The objective of this study was to investigate the relationship between flow velocity and thermal stability of the waterbody using a three-dimensional (3D) hydrodynamic model (EFDC+) after calibration against the thermistor chain data obtained in 2014. A new Sigma-Zed vertical grid system of EFDC+ that minimize the pressure gradient errors was used to better simulate the thermodynamics of the waterbody. The model reasonably simulated the vertical profiles of the observed water temperatures. The vertical mean flow velocity and the Richardson Number (Ri) that represents the stability of waterbody were estimated for various management water levels and flow rates scenarios. The results indicated that the thermal stability of the waterbody is mostly high ($Ri{\gg}0.25$) enough to establish stratification, and largely depend on the flow velocity. The critical flow velocity that can avoid a persistent thermal stratification was found to be approximately 0.1 m/s.

• Natural Product Sciences
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• v.23 no.3
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• pp.201-207
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• 2017

Angelica decursiva has been utilised as remedy for controlling the airway inflammatory diseases in folk medicine. We investigated whether nodakenin, columbianadin, and umbelliferone isolated from the roots of Angelica decursiva inhibit the gene expression and production of MUC5AC mucin from human airway epithelial cells. Confluent NCI-H292 cells were pretreated with nodakenin, columbianadin or umbelliferone for 30 min and then stimulated with epidermal growth factor (EGF), phorbol 12-myristate 13-acetate (PMA) or tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) for 24 h. The MUC5AC mucin gene expression was measured by reverse transcription - polymerase chain reaction (RT-PCR). Production of MUC5AC mucin protein was measured by enzyme-linked immunosorbent assay (ELISA). The results were as follows: (1) Nodakenin did not affect the expression of MUC5AC mucin gene induced by EGF, PMA or $TNF-{\alpha}$. Columbianadin inhibited the expression of MUC5AC mucin gene induced by EGF or PMA. However, umbelliferone inhibited the expression of MUC5AC mucin gene induced by EGF, PMA or $TNF-{\alpha}$; (2) Nodakenin also did not affect the production of MUC5AC mucin protein induced by EGF, PMA or $TNF-{\alpha}$. Columbianadin inhibited the production of MUC5AC mucin protein induced by PMA. However, umbelliferone inhibited the production of MUC5AC mucin protein induced by EGF, PMA or $TNF-{\alpha}$. These results suggest that, among the three compounds investigated, umbelliferone only inhibits the gene expression and production of MUC5AC mucin stimulated by various inducers, by directly acting on airway epithelial cells, and the results might explain the traditional use of Angelica decursiva as remedy for diverse inflammatory pulmonary diseases.

• Journal of Microbiology
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• v.41 no.2
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• pp.148-151
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• 2003

Waterborne parasite infections are considered a reemerging threat. Most studies on the epidemiology of human cryptosporidiosis, giardiasis, and amebiasis have been carried out in developed countries, and there is little data on the occurrence of these infections in other areas. The objective of this study was to investigate the presence of waterborne parasites such as Cryptosporidium parvum, Giardia lamblia and Entamoeba histolytica in various water samples in Ankara, turkey. A total of 85 samples were examined, 43 from the municipal water supply, 34 from wells, 6 from the Ankara River, and 2 from two untreated dams; by conventional microscopy, immunologically and by polymerase chain reaction (PCR). Oocysts of C. parvum and cysts of G. lamblia were detected by using an indirect fluorescence (antigen) assay, whereas an enzyme linked immunosorbent assay was used to detect the cysts of E. histolytica and E. dispar. In addition, PCR was used for E. histolytica, E. dispar, C. parvum and G. lamblia detection. G. lamblia was found in 2 of the 34 well water samples, and parasites were found in 3 of the 6 Ankara River samples. The 1$\^$st/ contained E. histolytica cysts and Strongyloides stercoralis larvae. the 2$\^$nd/ E. histolytica cysts, and Trichuris trichiura eggs, and the 3$\^$rd/ C. parvum oocysts only. No parasite was observed in the municipal water samples and untreated dam water samples. These results extend our knowledge on waterborne parasites, such occurrence information on waterborne pathogens assists the management and treatment of municipal water.

• The Journal of Fisheries Business Administration
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• v.35 no.1
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• pp.57-85
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• 2004

To develop an blue tourism website(BTW) for electronic commerce(EC), information requirements of BTW are defined firstly. We defined information requirements of BTW from two aspects, i.e., front office and back office. Information requirements for front office were derived by consumer purchasing decision process. And information requirements for back office were derived by tourism value chain. Total 29 functions are identified as critical EC related functions of BTW. Among them, 25 functions were investigated into BTW. BTWs were searched by search engines - Yahoo and Empas - to Korean websites. There are 12 specialized BTWs, except one cyber museum website. For 12 websites, 25 functions were probed. By the results, in need recognition stage of blue tourism, only weather information was provided in most websites. In information search stage of blue tourism, package recommendation and various contents were provided in most websites. In consumption stage of blue tourism, traffic information were provided in most websites. And in after - sales service stage of blue tourism, bulletin board function was implemented in most websites. The rest of the functions were scarcely implemented. On the whole, it was concluded that most EC related functions of BTW in Korea were not implemented properly. To improve the status quo, it is expected in the dimension of individual website, that marketing planning, customized service, intelligent service, reinforcing purchasing assistance functions, customer relationship management, and escrow service etc. need to be implemented. And it is expected in the dimension of blue tourism industry, that standardizing product catalog, security assistance policy, information sharing by industrial database, finding referral model of BTW, elevating information mind, revising related laws etc. are needed.

• Journal of Periodontal and Implant Science
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• v.39 no.1
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• pp.37-44
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• 2009

Purpose: Tetracycline and its chemically modified non-antibacterial analogues can inhibit certain host-derived tissue destructive collagenases such as matrix metalloproteinases. The purpose of this study was to evaluate clinical and microbiologic effects of the subantimicrobial dose of doxycycline(SDD) in conjunction with scaling and root planing. Materials and methods: A total of 30 patients with chronic periodontitis who were going to receive scaling and root planing were randomly allocated to receive either a doxycycline hyclate for 3 months or nothing. Clinical probing depth, clinical attachment level, gingival recession, and bleeding on probing were measured by one periodontist. After a periodontal examination, microbial samples were collected using sterile paper points. The effect of SDD in conjunction with scaling and root planing on alterations of the periodontal pathogens (Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Porphyromonas gingivalis) were also assessed using l6S rRNA polymerase chain reaction. Results: During the treatment period, clinical parameters for both treatment group and control group were improved. After 3 months, reductions in probing depth and gains in clinical attachment level were significantly greater for the SDD group than control group. Microbial analysis showed that there was no alteration of the periodontal pathogens and no difference between the groups. Conclusion: This study suggested that the subantimicrobial dose of doxycycline as an adjunct therapy with scaling and root planing might be effective and safe in the management of chronic periodontitis.

• The Journal of Information Technology
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• v.7 no.1
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• pp.69-86
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• 2004

In this paper, a conceptual framework describing the dynamics of click and mortar businesses is provided. It directs our attention to the many potential sources of synergy that are available to firms that choose to integrate e-commerce with their existing traditional forms of business. It further emphasizes the many actions that firms can take to minimize channel conflicts and help achieve the benefits of synergy. Finally, it describes four categories of synergy-related benefits from the integration of e-commerce with traditional businesses, including potential cost saving, gains due to enhanced differentiation, improved trust, and potential extensions into new markets. The utility of the framework was demonstrated using the case of an electronics retailer that has chosen to tightly integrate its large chain of retail stores with its Web-based electronic store. The framework was also used to develop a series of propositions that can guide future empirical research. The discussion points to the need to develop new types of metrics to better judge the contributions of e-commerce channels, and provides some guidance for future empirical research that can test whether, and under what conditions, integrated click and mortar business models work well. Thus, the purpose of this study is to present the combining physical and virtual presence in e-commerce.

• Journal of Intelligence and Information Systems
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• v.13 no.1
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• pp.49-58
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• 2007

MDPDPTW (Multi-Depot Pickup and Delivery Problem with Time Windows) is a typical model among the optimization models based on the pickup and delivery flow in supply chains. It is based on multi-vehicles in multi-depots and does not consider moving vehicles near pickup and delivery locations. In ubiquitous environments, it is possible to obtain information on moving vehicles and their baggage. Providing the proper context from the perspective of moving vehicles and their baggage allows for more effective vehicle routings. This study proposes Integer Programming-based MDPDPTW including the information on moving vehicles and their baggage in a ubiquitous environment: u-MDPDPTW, and shows the viability and effectiveness of u-MDPDPTW through comparative experiments of MDPDPTW and u-MDPDPTW.

• Journal of Distribution Research
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• v.13 no.4
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• pp.1-19
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• 2008

This study investigated the international transfer of retail know-how via the prism of Learning Organizational Theory. As a case, 7-Eleven, a worldwide chain of convenience stores was examined. Its international transfer of retail know-how occurred when 7-Eleven, originally founded by Southland Corporation in Dallas, Texas, was introduced in Japan in 1973 in the form of 7-Eleven Japan. Our analysis shows that both strategic core learning and adaptive learning played a significant role during the international transfer of retail know-how. Our findings reveal the evidence of the following elements of strategic core learning such as the convenience store concept, the three principles of store management, the minimum profit guarantee system, and the margin-based royalty system. On the other hand, the retailing mix such as store type, store location, store size, and merchandising acted as the acting agents of adaptive learning. The hypothesis verification methods acted as the main methods for adaptive learning. Through the persistent adaptive learning, inimitable innovations could be brought forth. However, the elements of strategic core learning should provide the direction for the adaptive learning.

• Journal of Veterinary Science
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• v.22 no.6
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• pp.67.1-67.7
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• 2021

Background: Chlamydophila felis, formerly known as Chlamydia psittaci var. felis, is frequently associated with ocular, respiratory, and occasionally reproduction tract infections. Even though the infection is sometimes asymptomatic, it potentially results in a latent immunosuppressive infection. Objective: This study aimed to identify occurrences of feline chlamydophilosis, rarely reported in cats in Indonesia. Methods: The observation was conducted in three cats with clinical signs of Cp. felis infection, particularly relapsing conjunctivitis. The cats' histories were recorded based on owners' information. Conjunctival swabs were sampled for cytology examination and molecular assay detection. A phylogenetic tree was generated using MEGA-X software to reveal group clustering. A post-mortem examination was performed on the cat that died during an examination. Results: Cp. felis was detected in both cytological examination and polymerase chain reaction assay. The phylogenetic tree demonstrated that the Cp. felis isolated in this study clustered with several other isolates from the other countries. Cp. felis can be isolated from cats with different clinical manifestations and levels of severity. The chronic fatal infection demonstrated interstitial broncho-pneumonia under histopathological examination. Conclusions: Molecular assay of Cp. felis is always recommended to obtain a definitive diagnosis of feline chlamydophilosis since the disease can have various clinical manifestations. Even though it may be subclinical and is often not fatal, an infected cat may be a carrier that could spread the pathogen in the surrounding environment. Serious disease management is suggested to avoid high costs associated with regularly relapsing disease.

• Journal of Veterinary Science
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• v.22 no.2
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• pp.24.1-24.16
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• 2021

Background: Bovine tuberculosis (TB) is caused by Mycobacterium bovis, a well-known cause of zoonotic tuberculosis in cattle and deer, and has been investigated in many physiological and molecular studies. However, detailed genome-level studies of M. bovis have not been performed in Korea. Objectives: To survey whole genome-wide single-nucleotide polymorphism (SNP) variants in Korean M. bovis field isolates and to define M. bovis groups in Korea by comparing SNP typing with spoligotyping and variable number tandem repeat typing. Methods: A total of 46 M. bovis field isolates, isolated from laryngopharyngeal lymph nodes and lungs of Korean cattle, wild boar, and Korean water deer, were used to identify SNPs by performing whole-genome sequencing. SNP sites were confirmed via polymerase chain reaction using 87 primer pairs. Results: We identified 34 SNP sites with different frequencies across M. bovis isolates, and performed SNP typing and epidemiological analysis, which divided the 46 field isolates into 16 subtypes. Conclusions: Through SNP analysis, detailed differences in samples with identical spoligotypes could be detected. SNP analysis is, therefore, a useful epidemiological tracing tool that could enable better management of bovine TB, thus preventing further outbreaks and reducing the impact of this disease.