• Title/Summary/Keyword: Competing interaction

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The Effect of Polyethylene Oxide on the Aggregation State and Toxicity of Amphotericin B (폴리에틸렌 옥사이드가 암포테리신-B의 응집 특성 및 독성에 미치는 영향)

  • Yu, Bong-G.
    • Journal of Pharmaceutical Investigation
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    • v.31 no.1
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    • pp.7-12
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    • 2001
  • Amphotericin B (AmB) is a drug of choice for the treatment of systemic fungal diseases, but its use is considerably limited due to a high incidence of toxicity, particularly nephrotoxicity. It has been demonstrated that the toxicity of AmB is caused by self-aggregated species of the drug and that unaggregated (monomeric) drug is nontoxic but still expresses antifungal activity. Poly (ethylene oxide) (PEO) is a water-soluble polymer, which may impact the aggregation state of AmB. We have studied the aggregation state of AmB as a function of PEO molecular weight and concentration. At 3,000 and 8,000 g/mole, there was minimal or no change of critical aggregation concentration (CAC) of AmB regardless of the concentration of polymer. By contrast at 20,000 g/mole, the CAC of AmB strikingly increased to 24.3 and $37.5\;{\mu}M$ at 5.0% and 10 % w/v of polymer, respectively. The critical overlap concentration (COC) of PEO 20,000 g/mole was 5.5%. It appears that an interaction between monomeric AmB and polymer coil increases above the COC, competing with self-aggregation of the drug. Accordingly, the degree of aggregation of AmB stayed low and the toxicity became less. There was no such effect at 3,000 and 8,000 g/mole of PEO, owing perhaps to small dimensions in comparison to AmB. Based upon these findings, less toxic AmB formulation may be developed by a pharmaceutical technique such as solid dispersion system containing both AmB and PEO 20,000 g/mole.

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The Binding of Aflatoxin $B_1$ Modulates the Adhesion Properties of Lactobacillus casei KCTC 3260 to a HT29 Colon Cancer Cell Line

  • Hwang, Kwon-Tack;Lee, Won-Jae;Kim, Gye-Yeop;Lee, Shin-Kyung;Lee, Jeong-Min;Jun, Woo-Jin
    • Food Science and Biotechnology
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    • v.14 no.6
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    • pp.866-870
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    • 2005
  • The 14 lactic acid bacteria (LAB) have been evaluated to determine the binding capacity to HT29 cell and Aflatoxin $B_1$ ($AFB_1$). The interaction of LAB to HT29 cells has been further investigated to identify the possibility of competing the binding sites with $AFB_1$. Of 14 LAB strains, Lactobacillus casei KCTC 3260 demonstrated the higher adhesiveness to HT29 and $AFB_1$ with the rate of 19.6% and 46.3%, respectively. In competitive analysis for binding sites, the adhesion of L. casei KCTC 3260 to HT29 cells was reduced with 100 nmol $AFB_1$ by 31.2%. The protoplast of L. casei KCTC 3260 showed no binding capacity to HT29 cells with increment of $AFB_1$ concentration, indicating that cell wall components might serve as a critical factor for the binding. To discriminate the major component influencing on L. casei KCTC 3260 binding to HT29 cells and $AFB_1$, four different pre-treatments (lipase, pronase E, sodium m-periodate, and urea) were employed. Of those, sodium m-periodate treatment caused the lower adhesion of L. casei KCTC 3260 to HT29 cells with the increment of $AFB_1$ concentration. These results indicated that carbohydrate moiety on the cell wall of L. casei KCTC 3260 might be the most critical component in binding to both HT29 cells and $AFB_1$.

The Molecular Mechanism of Long Non-Coding RNA MALAT1-Mediated Regulation of Chondrocyte Pyroptosis in Ankylosing Spondylitis

  • Chen, Wei;Wang, Feilong;Wang, Jiangtao;Chen, Fuyu;Chen, Ting
    • Molecules and Cells
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    • v.45 no.6
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    • pp.365-375
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    • 2022
  • Long non-coding RNAs (lncRNAs) may be important regulators in the progression of ankylosing spondylitis (AS). The competing endogenous RNA (ceRNA) activity of lncRNAs plays crucial roles in osteogenesis. We identified the mechanism of the differentially expressed lncRNA MALAT1 in AS using bioinformatic analysis and its ceRNA mechanism. The interaction of MALAT1, microRNA-558, and GSDMD was identified using integrated bioinformatics analysis and validated. Loss- and gain-of-function assays evaluated their effects on the viability, apoptosis, pyroptosis and inflammation of chondrocytes in AS. We found elevated MALAT1 and GSDMD but reduced miR-558 in AS cartilage tissues and chondrocytes. MALAT1 contributed to the suppression of cell viability and facilitated apoptosis and pyroptosis in AS chondrocytes. GSDMD was a potential target gene of miR-558. Depletion of MALAT1 expression elevated miR-558 by inhibiting GSDMD to enhance cell viability and inhibit inflammation, apoptosis and pyroptosis of chondrocytes in AS. In summary, our key findings demonstrated that knockdown of MALAT1 served as a potential suppressor of AS by upregulating miR-558 via the downregulation of GSDMD expression.

Groundwater-Stream Water Interaction Induced by Water Curtain Cultivation Activity in Sangdae-ri Area of Cheongju, Korea (청주 상대리지역에서 수막재배가 지하수-하천수 상호작용에 미치는 영향)

  • Moon, Sang-Ho;Kim, Yongcheol;Jeong, Youn-Young;Hwang, Jeong
    • Economic and Environmental Geology
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    • v.49 no.2
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    • pp.105-120
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    • 2016
  • Most of riverside in Korea, in case of application of water curtain cultivation (WCC) technique, has been inveterately suffering from the gradual drawdown of groundwater level and related shortage of water resources during the WCC peak time. We believe that the water resources issue in these riverside areas can be effectively solved when the interaction between groundwater and nearby surface water is well understood. To investigate the connection between stream and ground water, and the influence of stream water on the nearby aquifer, this study examined the water temperature and oxygen and hydrogen stable isotopic compositions. The study area is well-known strawberry field applying the WCC technique in Sangdae-ri, Gadeok-myon, Cheongju City, and the sampling was done from February 2012 through June 2014 for stream and ground water. Some groundwater wells near stream showed big temporal variations in water temperature, and their oxygen and hydrogen stable isotopes showed similar compositions to those of adjacent stream water. This indicates that the influence of stream water is highly reflected in the stable isotopic composition of groundwater. Four cross-sectional lines from stream to hillside were established in the study area to determine the spatial differences in water quality of wells. At the late stage of WCC in February to March, groundwater of wells in line with short cross-sectional length showed the narrow range of isotopic compositions; however, those in the long cross-sectional line showed a wide compositional range. It was shown that the influence of the stream water at the late WCC stage have reached to the distance of 160 to 165 m from stream line, which is equivalent to the whole length and one-third point in each short and long cross-sectional line, respectively. Therefore, the wide compositional range in the long cross-sectional lines was not only due to the influence of stream water, but apparently resulted from the change of relative impact of each groundwater supplying from two or more aquifers. In view of stable isotopic compositions, there seems to be three different aquifers in this study area, which is competing for dominance of water quality in wells at each period of WCC.

A comparative study on user interface experience, product attitudes and intention to repurchase for each smartphone manufacturer (스마트폰 제조사별 UI(User Interface)경험과 제품태도 및 재구매의도에 관한 비교 연구)

  • Youm, Dongsup;Park, Kyoung-Ha
    • Journal of Digital Convergence
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    • v.12 no.9
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    • pp.359-367
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    • 2014
  • This study aimed to identify empirically the differences of user interface experience factors for such manufacturers as Samsung, LG, Sky, Apple, etc., which are fiercely competing in the mobile market at home and abroad. In addition, this study aimed to verify how different the impact of such user interface experience factors on product attitudes and intention to repurchase would be for each manufacturer. As a result of the study, it was verified that there was a difference in the user experience between the manufacturers for all of the factors forming user satisfaction experience, which included information, interaction, useful experience and design experience satisfaction. Second, it was also verified that there was a difference between the manufacturers in terms of product attitudes. Lastly, it was verified that there was a difference between the manufacturers in terms of intention to repurchase. Specifically, it was found that Samsung had a higher degree of intention to repurchase than LG and Sky, whereas Apple had a higher degree hereof then Samsung. It is expected that the above results of study will provide the aforementioned manufacturers useful implications for establishing UI strategies through the contemplation of differences for each manufacturer in addition to the expansion of studies related to UI experience.

Small and Medium-Sized Stores′ Competitive Strategies, Marketing Capabilities, and Retail Performance: Competing against Mass Merchandisers (대형할인점에 대응하는 중소 소매점의 경쟁전략, 마케팅 역량 그리고 소매성과)

  • 전달영;채명수
    • Journal of Distribution Research
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    • v.8 no.1
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    • pp.91-116
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    • 2003
  • This study empirically analyzes the relationships among small and medium-sized stores' competitive strategies, marketing capabilities, and retail performance to cope with hostile environments like mass merchandisers' threats. To accomplish the proposed research objectives, data were collected from 325 small and medium-sized stores scattered nationwide. Three types of competitive strategies were significantly classified as follows cost leadership, merchandise differentiation, and service differentiation. Also, several strategic groups such as doing-nothing type, service differentiation type, cost leadership type, and merchandiser differentiation type were recognized through the cluster analysis. The test results show that the small and medium-sized stores perceiving hostile environments less importantly marked the high retail performance among clusters like cost leadership type, merchandise differentiation type, and even doing-nothing type. On the other hand, the moderating effects resulted from the interaction between strategic groups and environmental hostility did not have significant influence on retail performance. Additionally, merchandise differentiation cluster obtains and accumulates marketing capability most efficiently and the cluster like cost leadership, service differentiation, and doing-nothing follows next in order. Finally, merchandise differentiation cluster shows the most highest retail performance among the clusters while there was no difference between cost leadership and service differentiation cluster in terms of retail performance.

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A Study on the Interaction of a brand-image and design identity by a consubstantiality analysis (동질성 분석을 통한 디자인 아이덴티티와 브랜드이미지와의 상관관계에 관한 연구)

  • Seok, Jae-Heuck;Seong, Joo-Eun;Han, Jung-Wan
    • Archives of design research
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    • v.20 no.1 s.69
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    • pp.243-252
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    • 2007
  • Nowadays, technological differences between companies have decreased and products launched show more resemblance to each other. As an alternative plan companies started developing brands. The excellence in quality of a product from a company could be easily copied, but the formless value, brand, cannot be imitated easily. More importantly, in the globally competing generation the brand provides distinctiveness and gives a solution to the relationship between consumers. Also the design image takes a big part in a company's competitiveness. The design image that represents the company reflects the brand, and it reflects the image and the philosophy of the company. And the images of each product influence the brand. Also an effective delivery of a product image would give a synergistic effect on the brand. A company could build this design identity to elevate the brand. Therefore, the identity of design image reflects the brand. Therefore a study on the area of the absence and misled identity of design image is important. This study is fixed on the idea of, development of brand to increase competitiveness, and the affiliation of design image with the identity of the brand. This study, on the basis of preceding research and theoretical background, aims to find the design identity area focusing on the product design image of the product purchased by the consumer. Firstly, we need to examine the affinity of the product image from the consumer, and analyse the direction of images to offer a solution that could advance the design identity strategy.

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Analysis of Relationship between Nursing Organization Culture and Organizational Commitment (간호사가 지각하는 간호조직문화와 조직몰입간의 관계 분석)

  • Kim, Dae-Ran;Kim, In-Sook
    • Journal of Korean Academy of Nursing Administration
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    • v.5 no.1
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    • pp.5-21
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    • 1999
  • Nursing organization culture is common patterns of believing, thinking and behaving resulted from a variety of experiences and interaction nurses in the same setting. This study was performed based on the assumption of existence of different subcultures within meta-culture, to identify the differences of subculture among 5 nursing units and to analyze the relationship between nursing organization culture and organizational commitment In this study, two kinds of instruments were used. One was the instrument of nursing organization culture developed by researcher through literature review and interview with nurses. The other one was Mowday's Organizational Commitment Questionnaire to measure organizational commitment of nurses. Both of them were structured with 5 scale. The answers were analyzed using SPSS program. The results were as follows : The meta-culture of the nursing organization culture was the people stable culture. There were significant differences in people development culture and people stable culture among 5 nursing units and all 5 units had different culture score. Especially, emergency room had strong development culture, and stable culture was dominant in operating room. Other units except emergency room and operating room had high scores in people stable culture than other culture types, but revealed different distribution. There were significant differences of the nursing organizational culture types -people development, task development, people stable, task stable-among 5 units. Four types of nursing organizational culture consisted of competing values in one organization. Nurses's organizational commitments were sign ificantly different among the units. The score per ceived by nurses who work in emergency room, operating room and leu was higher commitment score than that of medical/surgical nursing units Nurse's commitment to nursing organization was also related to total work period as nurse in any setting and work period in this hospital. Organizational commitment was significantly different among the nursing culture types, indicating that the scores of developmental culture were higher than stable culture. In conclusion, there were many different subcultures in nursing organization. In subculture, the organizational commitment was different. Therefore, the change of nursing organization culture or nursing unit culture needs to be considered to hire, give orientation, teach. and reallocate nurses efficiently. Research on nursing organization culture using both qualitative and quantitative method needs to be further considered. Furthermore, the strategy in nursing organization culture for nursing administrator to manage human resources efficiently and to change nursing unit effectively, needs to be developed.

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On Generating a Dynamic Price Formation System with Rationality -Application to U.S. Fisheries- (합리성을 가진 동태적 가격형성모형의 연구 -U.S. 수산자원에의 응용-)

  • Park, Hoanjae
    • Environmental and Resource Economics Review
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    • v.14 no.3
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    • pp.699-728
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    • 2005
  • This article is basically an extension of Barten(1993), Brown et al. (1995), Holt and Bishop's(2002) price formation system. A new dynamic price formation system is attempted considering full rationality of the consumers' side. The underlying idea of the new dynamic price formation system is that consumers are rational and farsighted and thus consider past and future consumptions in addition to current consumption to accept the prices traders called. In an empirical application, the U.S. commercial fish demand data are particularly interesting to this analysis in which the species are over fished, including many of the most valuable species. Especially, the grouper-snapper complex are under management jurisdiction of the National Marine Fisheries Council. In the empirical section, it shows how to adapt the model to estimate the marginal values to consumers of commercial fisheries. Since it is conceived of regulations as inducing movements along the marginal value curves, it is of growing importance to regional and national policy makers who are confronted with competing claims on diminishing fish stocks by commercial fisheries interests. It performs well and shows the plausible signs and magnitudes of price flexibilities and interaction among species. It further contributes to the general methodology of applied economics.

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Spatial Point Pattern Analysis of Riparian Tree Distribution After the 2020 Summer Extreme Flood in the Seomjin River (2020년 여름 섬진강 대홍수 이후 하천 수목 분포에 대한 공간 점 패턴 분석)

  • Lee, Keonhak;Cho, Eunsuk;Cho, Jonghun;Lee, Cheolho;Kim, Hwirae;Baek, Donghae;Kim, Won;Cho, Kang-Hyun;Kim, Daehyun
    • Ecology and Resilient Infrastructure
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    • v.9 no.2
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    • pp.83-92
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    • 2022
  • The 2020 summer extreme flood severely disturbed the riparian ecosystem of the Seomjin River. Some trees were killed by the flood impact, whereas others have recovered through epicormic regeneration after the disturbance. At the same time, several tree individuals newly germinated. This research aimed to explain the recovery of the riparian ecosystem by spatial proximity between each tree individual of different characteristics, such as "dead", "recovered", and "newly germinated". A spatial point pattern analysis based on K and g-functions revealed that the newly germinated trees and the existing trees were distributed in the spatially clumping patterns. However, further detailed analysis revealed that the new trees were statistically less attracted to the recovered trees than the dead trees, implying competitive interactions hidden in the facilitative interactions. Habitat amelioration by the existing trees positively affected the growth of the new trees, while "living" existing trees were competing with the new trees for resources. This research is expected to provide new knowledge in this era of rapid climate change, which likely induces stronger and more frequent natural disturbance than before. Environmental factors have been widely used for ecosystem modeling, but species interactions, represented by the relative spatial distribution of plant individuals, are also valuable factors explaining ecosystem dynamics.