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Exploring naphthalimide derivatives as sensitisers for genosensors
Get PDFThis thesis is divided into five chapters.
The first chapter describes the structure of DNA and discusses the ways that small molecules can bind with DNA
and the driving forces for each mode of binding. Furthermore, the chapter describes how these small molecules
that bind with DNA can be applied as sensitizers to detect DNA. Lastly, I briefly describe several techniques that
can be used to detect ligand-DNA binding, including electrochemical techniques that can be applied in biosensors
and other biophysical techniques such as UV-visible titration, isothermal titration calorimetry (ITC), electron
paramagnetic resonance (EPR).
In chapter 2, a series of ferrocene-naphthalimide conjugates 2.12a-f and 2.13a,c,e were successfully synthesized
and characterized using NMR spectroscopy and mass spectrometry. In these compounds, the naphthalimide
scaffold is linked with a ferrocene moiety via a terminal diamine linker. Several solubilizing groups were introduced
on C4 in the naphthalimide scaffold to produce compounds 2.12a-f and 2.13a,c,f. These solubilizing groups (1°-
amine, 2°-amine and thiol group) have different effects on the solubility of the obtained ferrocene-naphthalimide
conjugates. Moreover, the solubilizing groups affect the DNA-binding affinities for these compounds which have
been studied using UV-visible titrations. Although most synthesised ferrocene-naphthalimide conjugates can be
considered weak binders, 2.12f and 2.13c bind strongly with DNA with binding affinities of 3.8x105 and 1.01x105
M-1, respectively. Generally, using linkers with different length to connect the naphthalimide scaffold and
ferrocene moieties did not play a significant role in terms of binding with DNA except for one case when
morpholine was used as a solubilizing group. In this case changing the length of the linker between the ferrocene
and the naphthalimide has a remarkable effect on improving the binding affinity where the compound with a
short linker 2.13c exhibits stronger binding affinity than the compound with the longer ether-based linker.
In chapter 3, a series of bisnaphthalimide derivatives has been synthesized where two naphthalimide units were
connected via several different linkers, including aliphatic, aromatic, and ether-containing linkers. Several
solubilizing groups, viz. 1°-amine, 2°-amine and thiol groups, were introduced to both C4 positions in the resulting
bisnaphthalimide scaffolds. The solubility for these compounds has been tested in MOPS buffer with solubilities
typically in the range of 10-6 M –1 ~10-5 M –1 except in case of using thioglycolic acid as a solubilizing group where
the solubility is higher and in the range of ~ x10-4 M. DNA-binding affinities were investigated using UV-visible
titrations. According to the DNA-binding affinities, most of the tested bisnaphthalimides such as 3.9e and 3.12d
can be considered good DNA binders with binding affinities of 6.13x104 and 1.24x104 M-1, respectively. On the
other hand, compound 3.10b is the most promising compound among this series as it binds relatively strongly
with DNA with binding affinity of 3.95 x105 M-1. Unsurprisingly, bisnaphthalimides connected with thioglycolic acid
do not bind with DNA due to the negatively charged carboxylates when the carboxylic acids get deprotonated in
solution and electrostatically prevent bisnaphthalimide from binding with negatively charged DNA.
In chapter 4, a series of fused-ring-extended 1,8-naphthalimide derivatives were successfully synthesized. The
synthesis involves synthesizing and separating two isomers of a building block for potential intercalators. Several
solubilizing groups were introduced in C4 of the naphthalene ring. The DNA-binding properties for these
compounds were studied using UV-visible titrations. It is found that this class of compounds binds strongly with
DNA, however the titration curves show unusual behavior where we had to analyse the data in a slightly different
way to obtain apparent DNA-binding affinities Kapp. In general, there is no difference between these isomers in
terms of binding with DNA. The binding properties for two isomers has remarkably improved when we used
different groups (1°-amin, 2°-amine, thiol group) compared to bromo-substituted isomers. Compound 4.16a, with
ethanolamine as the solubilizing group, is the most promising compound among this series with an apparent DNAbinding
affinity Kapp of 8.45´104 M-1. Using 2-mercaptoethanol 4.16d and 4.17d on the other hand show the lowest
DNA-binding affinities (~103 M-1). We note, however, that these binding affinities are apparent binding affinities
and therefore likely underestimate the actual affinities of these compounds for DNA.
In chapter 5, a series of mono- and bisnaphthalimide-TEMPO conjugates has been successfully synthesized. The
TEMPO moiety was connected to the naphthalimide scaffold using an amide-coupling reaction between 4-amino
TEMPO and a carboxylic acid group connected to the naphthalimide unit. The solubility of the synthesized monoand
bisnaphthalimide TEMPO conjugates has been tested in MOPS buffer. Understandably, bisnaphthalimide
derivatives were not sufficiently soluble but the mononaphthalimide-TEMPO conjugates are partially soluble.
DNA-binding properties for the synthesized mononaphthalimide derivatives were studied using UV-visible
titrations. Based on the binding affinities, this class of compound binds moderately with DNA. Among this series
of compound, 5.12e which contains two TEMPO moieties, binds with DNA better than the other compounds while
5.12b that involves morpholine as solubilizing group binds with DNA with lower affinity
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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