• Title/Summary/Keyword: Competing interaction

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Selective DNA Adsorption on Layered Double Hydroxide Nanoparticles

  • Kim, Kyoung-Min;Park, Chung-Berm;Choi, Ae-Jin;Choy, Jin-Ho;Oh, Jae-Min
    • Bulletin of the Korean Chemical Society
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    • v.32 no.7
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    • pp.2217-2221
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    • 2011
  • We investigated the selective deoxyribonucleic acid (DNA) adsorption on layered double hydroxide (LDH) nanoparticles via studying the interaction between positively charged LDH nanoparticle as adsorbent and negatively charged adsorbates such as methyl orange (MO), fluorescein (FL), and DNA strands. The size controlled LDH $(Mg_{0.78}Al_{0.22}(OH)_2(CO_3)_{0.11}{\cdot}mH_2O)$ was prepared by conventional coprecipitation method, followed by the hydrothermal treatment. According to the adsorption isotherms, the adsorbed amounts of MO and FL were similar, however, that of DNA were much larger. The adsorption behaviors were well fitted to Freundlich adsorption model. The concentration dependent adsorption behavior on LDH surface was described in order to verify the selective DNA separation ability. The result showed that the LDH has advantages in selective adsorption of DNA competing with single molecular anions.

Spin-glass behavior in (A,B)-site deficient manganese perovskites

  • Lee, Kyu-Won;Phan, Manh-Huong;Yu, Seong-Cho;Nguyen Chau;Tho, Nguyen-Duc
    • Proceedings of the Korean Magnestics Society Conference
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    • 2003.06a
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    • pp.150-151
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    • 2003
  • In the past years, a giant magnetoresistance (GMR) effect found in perovskite-like structured materials has attracted considerable attention among scientists and manufacturers, since, a practical point of view, the capacity of producing magnetic and sensing sensors. In a stream of this interest, further efforts to understand the underlying mechanism that leads to the GMR effect relative to the correlation between transport and magnetic properties, have been extensively devoted. In these cases, spin-glass-like behaviors are ascribed to the frustration of random competing exchange interactions, namely the ferromagnetic double-exchange interaction between Co$\^$3+/ (or Mn$\^$3+/) and Co$\^$4+/(or Mn$\^$4+/) and the antiferromagnetic one like spins. Noticeably, the distinction of spin-glass region from cluster-glass one, involved in the remarkable changes in transport and magnetic properties at a critical value of doping concentration, was observed. Magnetic anomalies in zero-field-cooled (ZFC) magnetization as well as ac magnetic susceptibility below Curie temperature T$\sub$c/ and the charge/orbital fluctuation were also realized. In this work, we present a study of magnetic properties of a deficient manganese perovskites system of La$\sub$0.6/Sr$\sub$x/MnTi$\sub$y/O$_3$, and particularly provide its new magnetic phase diagram.

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Peierls Instability and Spin Ordering in Graphene

  • Kim, Hyeon-Jung;Jo, Jun-Hyeong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.204-204
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    • 2012
  • Peierls instability and spin ordering of zigzag graphene nanoribbons (GNR) created on a fully hydrogenated graphene (graphane) are investigated as a function of their width using first-principles density-functional calculations within the generalized-gradient approximation. For the width containing a single zigzag C chain (N=1), we find the presence of a Peierls instability with a bond alternated structure. However, for width greater than N=1, the Peierls distortion is weakened or disappears because of the incommensurate feature of Fermi surface nesting due to the interaction of C chains. Instead, there exists the antiferromagnetic (AFM) spin ordering in which the edge states are ferromagnetically ordered but the two ferromagnetic (FM) edges are antiferromagnetically coupled with each other, showing that electron-lattice coupling and spin ordering in GNR are delicately competing at an extremely thin width of N=2. It is found that, as the width of GNR increases, the energy gain arising from spin ordering is enhanced, but the energy difference between the AFM and FM (where two edge states are ferromagnetically coupled with each other) orderings decreases.

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An Evaluation of Human-Product Interface Usability (인간-제품 인터페이스의 사용성 평가)

  • 최재하;박영택
    • Proceedings of the ESK Conference
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    • 1997.10a
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    • pp.249-259
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    • 1997
  • As the gap between competing products narrows in terms of performance and quality, the product usability is rapidly becoming a new dimension of product design as the key to offering distinctive value to the customer. Because the user interface is important, not only for the user but also for the efficiency of te whole organiation, system designers require increasingly precise evaluation methods to determine how effective and usable human-product interface is. In this study a new methodology named usability analysis diagram(UAD), for evaluating usability of human-product interface systematically, was developed. UAD is a top-down flow diaagram of a human-product interaction, in ehichfour basic elements - perception, understanding, intellectual decision and action - were classified and then represented by a particular symbol for each. The usability of the product is assessed by the frequency of each symbol in a diagram which represents a sequence of cognitive and physical activities of users during the use of the product, and by the level of difficulty that is classif- ied in three levels in terms of easiness of perception, understanding and action. In order to test validity of the proposed UAD in a real situation, a case study was performed on two different cameras, automatic and manual, and their usability was successfully evaluated and compared.

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A Quinoline carboxamide based Fluorescent Probe's Efficient Recognition of Aluminium Ion and its Application for Real Time Monitoring

  • Manivannan, Ramalingam;Ryu, Jiwon;Son, Young-A
    • Textile Coloration and Finishing
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    • v.32 no.4
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    • pp.185-192
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    • 2020
  • A novel binding site for metal ion made by designing molecule with tetrazolo quinoline with hydrazine carboxamide (TQC) and the designed molecule successfully synthesized. The probe works by selectively detecting Al3+ ion via both fluorimetric and colorimetric approach. The probe's effectiveness towards aluminium ion detection is highly sensitive and selective with no substantial interference with other competing ions. The added Al3+ ion to TQC fetched a rapid change of visual color to yellow from colorless, also the response of fluorescence turn-on. The fluorescence turn-on and color change visibly by the probe TQC with Al3+ ion credited to the ICT phenomenon (intramolecular charge-transfer transition). The likely interaction of the probe with aluminium ion has also been there predicted from ESI-MS spectral analysis results. The usefulness of the probe confirmed by practical utility by making a test kit to monitor Al3+ ion in water which showed a naked eye detection by notable color change.

Perseverance or Pivot? The Role of Problem-Solving Strategies on Individual Entrepreneurial Orientation and New Problem-Solving (개인의 기업가지향성과 문제해결전략이 새로운 문제 도전에 미치는 영향)

  • Kim, Jinyoung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.13 no.6
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    • pp.117-127
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    • 2018
  • When we face an unexpected challenge, should we stick to the original plan and persevere through the series of challenges? Or shall we pivot and transform our original plan into something new by taking into account the newly acquired information? This perennial question of perseverance versus pivot as two competing problem-solving strategies has puzzled our every day lives. In this study, based on the large-scale, nation-wide survey on entrepreneurship, I found that individual entrepreneurial orientation, which consists of innovativeness, risk-taking, and proactiveness, promotes an individual's tendency to choose new problems to solve. Perseverance strategy was found to positively moderates the relationship between innovativeness and the tendency to choose new problems to solve, whereas the relationship between risk-taking and the tendency to choose new problems to solve was found to be negatively moderated by perseverance strategy. Pivot strategy, on the other hand, was found to be positively moderates the relationship between proactiveness and the tendency to choose new problems to solve. These findings contributes to the stream of individual entrepreneurial orientation research by empirically testing two competing problem-solving strategies of perseverance and pivot to show their interaction effects with entrepreneurial orientation. Also the findings of this study expand the potential outcome of entrepreneurial orientation by adding an individual's tendency to choose new problems to solve rather than what he or she has already experienced before.

Competition and Host-strain Interaction of Soybean Rhizobium Strains on Two Soybean Cultivars (콩 근류균계간 경합과 숙주 친화성의 품종간 차이)

  • 박의호;싱글톤폴
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.41 no.6
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    • pp.718-724
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    • 1996
  • Two soybean cultivars, ‘Lee’ and ‘Peking’, were used to evaluate the competition and interaction of rhizobium strains PRC205 (R. fredii, fast-grower) and USDA110 (B. japonicum, slow-grower). Strains were inoculated separately on the root parts of a split-root growth system. Both root sides were inoculated simultaneously with four combinations of strain treatment to evaluate the competition of strains. And to evaluate the interaction of strains one side of split-root system was inoculated a week prior to the other side. Nodule mass and dry weight of the plants were measured 3 weeks after treatments. PRC205 showed no effective nodulation and no competing ability with USDA110 on Lee cultivar, however, contrary results on Peking cultivar. Top dry weight of Lee inoculated with PRC205 was much lower than that of any other inoculation treatments, however, in Peking that with PRC205 was higher than that with USDA110. There were no differences in root dry weight among the inoculation treatments. USDA110 used as primary inoculant suppressed nodule mass of opposite side, secondary inoculant, severely in both cultivars. PRC205 showed same tendency as USDA110 in Peking, but revealed little suppression effects on USDA110 used as secondary inoculant in Lee. USDA110 used as primary inoculant in Lee and PRC205 in Peking showed much more dry weight of soybean plants than that of other treatments.

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A Study on the Introduction of Linear Programming Model into the Management of Korean Coastal and Offshore Fisheries (한국 연근해어업의 합리적 관리를 위한 LP모형의 도입방안에 관한 연구)

  • 박장일
    • The Journal of Fisheries Business Administration
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    • v.25 no.1
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    • pp.37-59
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    • 1994
  • Many studies to cope with the present problems of Korean coastal and offshore fisheries has been performed, but these were done partly in necessities and general studies for Korean inshore and offshore fisheries are in early stage. Most of these studies adopted analytical way of approach for each fishery individually and they could not reflect the effect of correlated interaction among fisheries on the several common species/stocks, and thus optimal effort allocation was impossible. To consider general fisheries and optimal effort allocation among competing mixed species, a linear programming (LP) approach is applied in this study and introduced into 16 important inshore and offshore fisheries with 13 constraining species which were chosen by annual yield order. This study is not based on the biological interaction among species (i.e., prey - predator system) but the technological interaction between species and fishing efforts. For the application of LP model in these fisheries, the standardization of fishing efforts through different fishing gears could not be successful and a new way of effort standardization through CPUE for vessel tonnage was originated. Total standardized fishing effort on a particular species i, Ei, is computed as the linear summation of standardized fishing effort generated by each fishery j. That is, (equation omitted) where $f_{j}$ is the total vessel tonnage of fishery j and aij is the coefficients contributing to the standardized fishing effort per ton for species i taken in fishery j. The total fishing effort level on species i due to both directed fishing and by - catch can thus be accounted in the aij's. Optimal effort allocation among the j fisheries may be considered a minimizing problem (minimize $\Sigma$ $f_{j}$), subject to the constraints that standardized fishing effort levels on particular species are maintained at, above, and below certain predefined levels. Fishing effort goals for individual species can be based on various biological and/or economic criteria, i.e., fishing effort level generating maximum sustainable yield and/or maximum economic yield. But in this study the $F_{0.1}$ criteria which was accepted as an approximate level for $F_{mey}$ by Outland and Boerema's (1973) study. The findings of this study are, (1) LP model can be applied to the Korean inshore and offshore fisheries giobally. (2) Through a new way of combining multiple different fisheries' efforts for a particular species together generating standardized fishing effort, Schaefer curve could be applied to the complex system successfully. (3) The results of this study for total reduction scale were mostly the same as those of prior studies, but different much from the individual scales of reduction. This study showed the necessities for exploitation of more concrete parameters to put into consideration of profitability of fisheries and social factors, and this model can be modified according to the actual constraints. Also, considering the age structure of stocks, this model can be developed into better one for better fisheries management.ent.

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Application and Effect of Remediation in Web Design (웹 디자인에서의 리미디에이션의 활용과 효용)

  • 서현석;서종환
    • Archives of design research
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    • v.17 no.2
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    • pp.113-122
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    • 2004
  • Modern society came to enjoy dramatically advanced information technologies by the digitalization of New Media with the improvement of communication technologies and interaction between various information system and technologies. New service by web, not only text but image, audio and moving image have opened new experience possible for us. The development was possible because the web has characteristics of media making Remediation of various media possible. The web has remediated newspaper, magazines, TV, audio, movie by taking them, competing with them, attacking them and absorbing them. As a result, now we can enjoy various characteristics of different media at the Web. This study is to look into the effectiveness of Remediation at web design through various case studies. This study also is to seek more effective methods of expressions in the web and future improvement direction.

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Expression, Purification, and Biological Characterization of The Amino-Terminal Fragment of Urokinase in Pichia pastoris

  • Li, Jianping;Lin, Yuli;Zhuang, Hongqin;Hua, Zi-Chun
    • Journal of Microbiology and Biotechnology
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    • v.23 no.9
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    • pp.1197-1205
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    • 2013
  • Urokinase (uPA) and its receptor (uPAR) play an important role in tumor growth and metastasis. Targeting the excessive activation of this system as well as the proliferation of the tumor vascular endothelial cell would be expected to prevent tumor neovasculature and halt the tumor development. In this regard, the amino-terminal fragment (ATF) of urokinase has been confirmed as effective to inhibit the proliferation, migration, and invasiveness of cancer cells via interrupting the interaction of uPA and uPAR. Previous studies indicated that ATF expressed in Escherichia coli was mainly contained in inclusion bodies and also lacked posttranslational modifications. In this study, the biologically active and soluble ATF was cloned and expressed in Pichia pastoris. The recombinant protein was purified to be homogenous and confirmed to be biologically active. The yield of the active ATF was about 30 mg/l of the P. pastoris culture medium. The recombinant ATF (rATF) could efficiently inhibit angiogenesis, endothelial cell migration, and tumor cell invasion in vitro. Furthermore, it could inhibit in vivo xenograft tumor growth and prolong the survival of tumor-bearing mice significantly by competing with uPA for binding to cell surfaces. Therefore, P. pastoris is a highly efficient and cost-effective expression system for large-scale production of biologically active rATFs for potential therapeutic application.