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Bacterial Logic Devices Reveal Unexpected Behavior of Frameshift Suppressor tRNAs

  • Sawyer, Eric M.;Barta, Cody;Clemente, Romina;Conn, Michel;Davis, Clif;Doyle, Catherine;Gearing, Mary;Ho-Shing, Olivia;Mooney, Alyndria;Morton, Jerrad;Punjabi, Shamita;Schnoor, Ashley;Sun, Siya;Suresh, Shashank;Szczepanik, Bryce;Taylor, D. Leland;Temmink, Annie;Vernon, William;Campbell, A. Malcolm;Heyer, Laurie J.;Poet, Jeffrey L.;Eckdahl, Todd T.
    • Interdisciplinary Bio Central
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    • v.4 no.3
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    • pp.10.1-10.12
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    • 2012
  • Introduction: We investigated frameshift suppressor tRNAs previously reported to use five-base anticodon-codon interactions in order to provide a collection of frameshift suppressor tRNAs to the synthetic biology community and to develop modular frameshift suppressor logic devices for use in synthetic biology applications. Results and Discussion: We adapted eleven previously described frameshift suppressor tRNAs to the BioBrick cloning format, and built three genetic logic circuits to detect frameshift suppression. The three circuits employed three different mechanisms: direct frameshift suppression of reporter gene mutations, frameshift suppression leading to positive feedback via quorum sensing, and enzymatic amplification of frameshift suppression signals. In the course of testing frameshift suppressor logic, we uncovered unexpected behavior in the frameshift suppressor tRNAs. The results led us to posit a four-base binding hypothesis for the frameshift suppressor tRNA interactions with mRNA as an alternative to the published five-base binding model. Conclusion and Prospects: The published five-base anticodon/codon rule explained only 17 of the 58 frameshift suppression experiments we conducted. Our deduced four-base binding rule successfully explained 56 out of our 58 frameshift suppression results. In the process of applying biological knowledge about frameshift suppressor tRNAs to the engineering application of frameshift suppressor logic, we discovered new biological knowledge. This knowledge leads to a redesign of the original engineering application and encourages new ones. Our study reinforces the concept that synthetic biology is often a winding path from science to engineering and back again; scientific investigations spark engineering applications, the implementation of which suggests new scientific investigations.

Evaluation of Thermoelectric Characteristics of Peltier Thermoelectric Module for Increasing Response Velocity in Shape Memory Alloy (SMA) Steering Catheter (형상기억합금(SMA) 스티어링 카테터의 반응속도 향상을 위한 펠티어 열전소자의 열전기적 특성 평가)

  • Oh, Dong-Joon;Kim, Cheol-Woong;Kim, Tae-Young;Lee, Ho-Sang;Kim, Jay-Jung
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.3
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    • pp.301-307
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    • 2010
  • Actuation using a shape memory alloy (SMA) is considered to be an important technology that will play a leading role in market for next-generation medical devices because an SMA actuator can accurately imitate skillful and delicate hand movements. However, SMA actuators have not been successfully used because of problems in control design caused by the nonlinear hysteresis effect of SMA, which leads to inaccuracies in control systems. In order to overcome the effect, the authors invented a SMA actuator, which could actively and rapidly cool down and heat up, by combining a SMA catheter and a TE module using the Peltier effect. In order to evaluate the TE characteristics of our TE module system, the changes in the temperature with 1) incremental increases in a continuous electric current and 2) the appearance of a discontinuous constant or reverse current are discussed in this paper.

The Significance of Gonadotropin Ratio in In Vitro Fertilization of Human Oocytes (성선 자극호르몬의 비율이 인간난자의 체외수정에 미치는 영향에 관한 연구)

  • Moon, Shin-Yong
    • Clinical and Experimental Reproductive Medicine
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    • v.15 no.2
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    • pp.135-147
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    • 1988
  • To compare the stimulation effect of the ratio in follicle stimulating hormone and luteinizing hormone in induction of multiple follicular growth, the serum E2 level, the diameter of follicle, number of aspirated follicles and cleavage rate of in vitro fertilized preovulatory oocytes as well as the pregnancy rate were evaluated. Forty one patients with irreparable tubal disease were stimulated by hMG(n=24) or FSH/hMG(n=17) for the purpose of in vitro fertilization and embryo transfer. The following results were obtained. 1. Serum estradiol(E2) levels on the day of hCG administration were 921.0±353.3pg/ml in hMG group and 1272.9±1060.6pg/ml in FSH/hMG group. The serum E2 value of hMG group was significantly lower than that of FSH/hMG group. 2. The diameter of leading follicle by ultrasonogram on the day of hCG administration were 16.2±2.0mm in hMG group and 16.2±2.6mm in FSH/hMG group. No significant difference of follicle diameter between two groups was demonstrated. 3. The number of follicles with diameter above 10 mm by sonogram on the day of hCG injection were 3.91±2.32 in hMG group and 6.52±3.86 in FSH/hMG group. There was significant difference of number of follicles between two groups, (p< 0.01). 4. The number of oocytes found per patient at aspiration were 2.59±1.00 in hMG group and 3. 76±2.31 in FSH/hMG group. There was significant difference of number of aspirated oocytes between two groups. (p< 0.05). 5. The detection rate of preovulatory oocyte at aspiration were 68.4%(39/57) in hMG group (n=22) and 77.6%(38/49) in FSH/hMG group (n=13). 6. The cleavage rate of preovulatory oocyte at 44 hours after insemination were 74.4%(29/39) in hMG group(n=22) and 81.6%(31/38) in FSH/hMG group (n=13). When only hMG was used, one pregnancy was established in 15 patients to whom 29 zygotes were transferred. And a full term normal female baby was delivered by elective cesarean section. In the FSH/hMG group, five pregnancies out of 9 transferred patients were confirmed by serum βhCG. Two pregnancies were spontaneously aborted before the 6th week of pregnancy. One patient aborted her baby at the 18th week of pregnancy because of incompetent internal os of the cervix. Two patients delivered two full term babies by elective cesarean section. From the above findings, paralell with the increase in the ratio of exogenous follicle stimulating hormone to luteinizing hormone, an increase in oocyte recovery was observed as well as an improvements in pregnancy rate. It was concluded that FSH enrichment early in the follicular phase had a beneficial effect in the controlled ovarian hyperstimulation.

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Inflammatory Mediators Modulate NK Cell-stimulating Activity of Dendritic Cells by Inducing Development of Polarized Effector Function

  • Kim, Kwang-Dong;Choi, Seung-Chul;Lee, Eun-Sil;Kim, Ae-Yung;Lim, Jong-Seok
    • IMMUNE NETWORK
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    • v.7 no.3
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    • pp.133-140
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    • 2007
  • Background: It is well established that cross talk between natural killer (NK) cells and myeloid dendritic cells (DC) leads to NK cell activation and DC maturation. In the present study, we investigated whether type 1-polarized DC (DC1) matured in the presence of IFN-γ and type 2-polarized DC (DC2) matured in the presence of PGE2 can differentially activate NK cells. Methods: In order to generate DC, plastic adherent monocytes were cultured in RPMI 1640 containing GM-CSF and IL-4. At day 6, maturation was induced by culturing the cells for 2 days with cytokines or PGE2 in the presence or absence of LPS. Each population of DC was cocultured with NK cells for 24 h. The antigen expression on DC was analyzed by flow cytometry and cytokine production in culture supernatant was measured by ELISA or a bioassay for TNF-α determination. NK cell-mediated lysis was determined using a standard 4h chromium release assay. Results: DC2, unlike DC1, had weak, if any, ability to induce NK cell activation as measured by IFN-γ production and cytolytic activity. DC2 were weakly stimulated by activated NK cells compared to DC1. In addition, IFN-γ-primed mature DC appeared to be most resistant to active NK cell-mediated lysis even at a high NK cell/DC ratio. On the other hand, PGE2-primed DC were less resistant to feedback regulation by NK cells than IFN-γ-primed mature DC. Finally, we showed that the differential effect of two types of DC population on NK cell activity is not due to differences in their ability to form conjugates with NK cells. Conclusion: These results suggest that different combinations of inflammatory mediators differentially affect the effector function of DC and, as a result, the function of NK cells, eventually leading to distinct levels of activation in adaptive immunity.

A Study on The Failure and Recovery of Korean Express Enterprise's Services -Focusing on Moderating Effect of Severity and Control- (한국 택배기업의 서비스 실패와 복구에 관한 연구 -심각성과 통제성의 조절효과를 중심으로-)

  • Wang, Min;Kim, Jong-Chill
    • International Commerce and Information Review
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    • v.14 no.4
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    • pp.227-252
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    • 2012
  • This paper is to study for causality validation of relation of the repair justice and repair satisfaction, relation between repair satisfaction and re-purchasing with South Korea's most important express service users. Through this research, we would like to confirm to seriousness of the failure express service and effects of controlling effectively adjust in relation between repair impartiality and satisfaction of repairs. The results of the study show as below. First, the result shows the justice outcome in express service, interaction justice, outcome justice in the relation of satisfaction with repair have regardful effects to the satisfaction of repair. This result explains that interaction justice has a positive influence. Second, in the relations between the procedural justice in express service and the satisfaction of repair, it is presented that the procedural justice has not regardful effects and results show differences from other leading researches. This result explains that procedural justice has not a positive influence. Third, as analyzing seriousness of the failure express service, controlling regulation effect in the relation of repair justice and repair satisfaction, seriousness of interaction and controlling regulation effect are not regardful effect in this relationship. These results are explained that the seriousness or controlling of the failure express service have not a positive influence to the relation of repair justice and repair satisfaction. Finally, in the relation between repair satisfaction and the intention to use again, repair satisfaction has a regardful effect to intention to use again. This result explained that it has positive influence to repair satisfaction and the intention to use again.

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Evaluating the perception of logistic firms and shipper on the relationship between contract term and service performance in logistics outsourcing service (물류아웃소싱 서비스에서 계약서 조항과 성과 간 관계에 대한 물류기업과 화주기업의 인식 비교 분석)

  • Kim, Jin-Su
    • International Commerce and Information Review
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    • v.18 no.1
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    • pp.151-178
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    • 2016
  • This study is based on precedent research on contract fairness to prevent irrational contract practices and enable long term mutual interests between logistic firms and shipper. Actual unjust contract examples were identified in order to help create this positive partnership. An analysis on the difference of perspective proved that while the logistics companies believed on the positive effects of the presence of additional expense clauses & potential risk clauses, the very same companies believed that the concretization of procedural & distributional equitability clauses will cause positive effects on the partnership between the logistics companies and the shipper. On the other hand, concretizationof the expense clauses brings about a negative effect for the shipper company. Also, the perspective of a logistics company appears that such results were identical to the empirical study which had a positiveeffect. However, the shipping company had a negative and a rather opposite point of view. These researches prove that there should be an alteration in perception for the shipper company. It is believed that the comparison of the results of this research and the leading researches may provide grounds for thought-provoking suggestions that must be concretized and also for those in need for further settlement for drafting the standardized logistics contract and its logistics.

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A Study on The Effectiveness of Tax Assistance System (조세지원체계의 유효성에 관한 연구)

  • Kim, Young-Il;Lee, Eun-Ha
    • Korean Business Review
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    • v.13
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    • pp.159-178
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    • 2000
  • Tax assistance system in Korea is a one that is designed by the central government to achieve specific policy objectives through the tax relief for economic activities or specific industries, leading to the development of the industries, Thus, the purpose of this study is to see if the government's direct tax assistance system for small and medium manufacturing firms is effective and then to contribute to establishing necessary policies for an effective tax assistance system based on the identification of a direct assistance system that is substantially useful to those firms. T- test was performed to see if there was a difference in tax burden between small and medium manufacturing firms and small and medium non-manufacturing firms and also to see whether the direct assistance system was effective. The results obtained from the statistical analyses are as follows: (1) The tax reduction rule applied to small and medium firms was turned out to be effective based on the fact that the effective tax rates of the small and medium firms to which the rule was applied were, on the average, significantly lower than those of the Listing large corporation which did not receive the tax benefit and also on the fact that the tax savings rates of the small and medium firms which could apply the rule were, on the average, significantly higher than those of the Listing large corporation to which the rule was not applied. (2) The tax credit rule applied to small and medium manufacturing firms was also turned out effective based on the same fact as described in the case of the application of the tax reduction rule.

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A Study on Micro-Electrode Pattern of Repair Process Using Electrohydrodynamic Printing System (전기수력학 프린팅 기술을 이용한 미세전극 패턴의 리페어 공정 적용에 관한 연구)

  • Yang, Young-Jin;Kim, Soo-Wan;Kim, Hyun-Bum;Yang, Hyung-Chan;Lim, Jong-Hwan;Choi, Kyung-Hyun
    • Clean Technology
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    • v.22 no.4
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    • pp.232-240
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    • 2016
  • Recently, various research studies have been conducted and many are in progress for the suitable alternative materials for ITO based touch screen panel (TSP) due to limitations in size and flexibility. Various researches from all over the world have been attempted to fabricate the fine electrode less than 5μm for the rapid developing of display technology. Research is also being carried out in metal mesh methods using the existing technologies and alternative materials at commercial level. However, by using the existing technologies certain discrepancies are observed like low transparency and low yield which also results in the distortion of patterns. For repairing the damaged pattern, the conventional laser CVD technique has also been used but there are some challenges observed in CVD technique like achieving a stable fine electrode of 10μm or less and avoiding the formation of satellite drops. To overcome these issues, a new printing process named Electrohydrodynamic (EHD) printing, has been introduced by which 5μm fine patterns can be printed in one step. This EHDA printing technique has been applied to print very fine electrodes of 5μm or less by using conductive inks of various viscosities. This study also presents the optimized process parameters for printing 5μm fine electrode patterns during experiments by controlling the applied voltage and supply flow rate. The 5μm repair electrodes were fabricated for repairing 50μm shorted electrode samples.

The Effect of Addictive Shopping Orientation on Post-purchase Emotions and Behaviors (패션제품 중독구매성향이 구매 후 감정 및 행동에 미치는 영향)

  • Lee, Jin-Hwa;Lee, Jeong-O
    • Management & Information Systems Review
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    • v.30 no.4
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    • pp.195-227
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    • 2011
  • There is no doubt that distribution channels and services greatly satisfy consumers' desires. Lots of products and services, stimulate consumers to purchase products to relieve their depressed feeling/stress temporarily, leading them gradually to a shopping addiction. Shopping addiction generates lots of problems, damaging not only consumers themselves but also other consumers and the entire society. Therefore, the purposes of this study were 1) to examine psychological factors that affected addictive shopping orientation of consumers, 2) to explore the effects addictive shopping orientation on the post-purchase emotions(positive emotion/negative emotion), 3) to examine the effect of post-purchase emotions on post-purchase behaviors (repurchasing/refund and exchange/negative word of mouth). 4) the study explored the differences in terms of effects of addictive shopping orientations on post-purchase emotions and behaviors, depending on the retailing channel (online and off line). The study performed a questionnaire survey for female adults older than 18 years old, living Seoul and Pusan areas. By using 404 copies for questionnaires, factor analysis, reliability analysis, and Amos 7.0 were used for the data analysis. It was found that psychological variables, self-esteem, compensatory buying and impulsiveness, had significant effects on addictive shopping orientations. Addictive shopping orientations affect both positive and negative post-purchase emotions in case of off-line shopping. Negative post-purchase emotions have higher impact on the postpurchase behaviors than positive post-purchase emotions.

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Effects of FIN-TECH use motivation on User Attitude and Word Of Mouth Intention: Focus on a Innovation Resistance Tendency and Type of Message (Rational, Emotional) (핀테크 이용 동기에 따른 이용자 태도와 구전의도의 관계 - 혁신저항과 메시지 유형의 조절효과 -)

  • Seol, Sang-Cheol;Jung, Sung-Gwang;Choi, Woo-Young
    • Management & Information Systems Review
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    • v.36 no.5
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    • pp.195-222
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    • 2017
  • Today's economy is becoming more and more convergence between different industries as the demarcation of the boundaries of all areas is leading to innovations such as mobile and social network services. So Fin-tech is a new technology that can combine the advantages of mobile and Internet with the technology revolution to easily handle financial and IT tasks. This Fin-tech is a compound word of finance and technology. The purpose of this study is to investigate the overall structural relationship between Fin-Tech use motivation (usefulness, enjoyment) on user attitude and word of mouth intention. In addition, we investigated how FinTech use motivation, user attitude, and word of mouth intention change according to innovation resistance tendency. And, we examined how the motivation, user attitude, and word of mouth intention of FinTech change according to the message type (rational and emotional). The main results of this study are as follows. First, the usefulness and enjoyment of motivation for using FinTech have a positive effect on user attitude, and user attitude also has a positive effect on word of mouse intention. Second, the relationship between FinTech use motivation, user attitude, and word of mouth intention was found to difference according to consumers' innovation resistance. Third, it was found that the relationship between FinTech use motivation, user attitude, and word of mouth intention differs according to type of message (rational, emotional). At the conclusion of the study, the summary of the research results, implications and limitations, and future research direction are described.