1,720,971 research outputs found
초파리 생체시계 유전자 Pdp1ε의 유전적 조절 인자에 관한 연구
No full text학위논문(석사) - 한국과학기술원 : 생명과학과, 2006.8, [ vi, 60 p. ]The Earth rotation causes periodic changes of light and temperature. A prediction of daily environmental changes has survival advantages to an organism which can adapt its behavior and physiology to the appropriate time of the day. For the reason, natural selection has favored the evolution of circadian clocks. The circadian clock consists of three parts, the input pathway, central clock oscillator, and output pathway. The Six groups of Drosophila clock pacemaker cells are revealed in adult fly brain. They are small and large lateral ventral neurons, lateral dorsal neurons, and three groups of dorsal neurons. The molecular components of the circadian pacemaker cells form two interlocked transcriptional negative feedback loops. In one loop, dCLK/CYC activates per and tim gene expression, and PER/TIM then inhibits dCLK/CYC activity. In the other loop, dCLK/CYC also activates vri and Pdp1ε gene expression, and VRI and PDP1ε then repress or activate dClk transcription.
In this study, we focused on the study of Pdp1ε gene. We developed a screen method to find out the genetic modifiers of Pdp1ε. Eye phenotype changes by overexpressed PDP1ε were used as the assay system for its genetic modifiers. The effect on the circadian behavior of candidate modifiers was also investigated. Moreover, two transgenic flies were also generated. One is Pdp1 -GAL4 driver and the other is Pdp1 RNAi strain. Features of them on the circadian system were also tested.한국과학기술원 : 생명과학과
파필로마바이러스 P3 프로모터에 관한 연구
No full text학위논문(석사) - 한국과학기술원 : 생물공학과, 1992.2, [ v, 52 p. ]Analysis of CAT plasmids containing BPV-1 (Bovine Papillomavirus Type-1) P3 promoter allowed identification of the promoter activity and E2 transactivator required for maximal transcription of the P3. The results showed that the P3 is very weak promoter and E2 transactivator requires for the maximal transcription of P3 promoter in a BPV-1 URR (Upstream Regulatory Region) dependent manner. It is suggested that an autoregulatory circuit based on the E2 protein is crucial. Furthermore, we removed portions of the 5`` or 3`` flanking sequence of P3 promoter using an exonuclease BAL 31 and characterized the transcriptional activity of the resulting deletion CAT mutants. This analysis showed that an upstream sequence, delimited by -320 (nt 576) bp and -94 (nt 802) bp with respect to the mRNA cap site, is required for the functional activity of P3 promoter. In contrast, very low levels of transcription were directed by constructs that contained 162 bp (-94 to +1 bp) of 5`` non-coding sequence, suggesting that the additional sequence (-302 to -94) further 5``exert a quantitative effect on transcription. Within this 226 bp region of P3 promoter, there are several sequence motifs, , SV40 enhancer core sequence and ATF binding site, highly analogous to the consensus sequence of binding sites for transcriptional regulatory proteins.한국과학기술원 : 생물공학과
A study on the increased expression of aminoglycoside-(3)-N-acetyltransferase gene on plasmid pSW1
No full text학위논문(석사) - 한국과학기술원 : 생물공학과, 1992.2, [ [vi], 43 p. ]한국과학기술원 : 생물공학과
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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