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DNA barcoding of medically important mosquitoes and molecular detection of Rickettsia felis in the mosquitoes and the blood of domestic dogs and cats
Get PDFRickettsia felis, an obligate intracellular bacterium, is the causative agent of human flea-borne spotted fever. The recent surge of reports of this disease has raised the concern of a near-future outbreak as the list of vectors, reservoirs, and hosts of this pathogen are increasing with recent studies. Due to the close inhabitation of humans and the mammalian hosts, cats and dogs, and the ubiquitous distribution of the main vector, Ctenocephalides felis, it is not uncommon for companion animals and humans to get infected with R. felis. Mosquitoes have also been found to carry this pathogen in different countries. As a result, this pathogen retains a potential to disseminate among the human population. Mosquito species identification was required to study field-level mosquitoes for R. felis. This thesis first establishes and validates a highly sensitive DNA barcoding method for medically important mosquitoes (Chapter 2). Then, the presence of R. felis DNA in mosquitoes and in the blood of domestic cats and dogs in the USA were investigated (Chapters 3 and 4).
Field level mosquitoes were trapped in Auburn, Alabama, with mosquito trappers. A SYBR-qPCR system targeting the mitochondrial Cytochrome Oxidase C Subunit 1 (COI) was developed, optimized, and validated for the accurate determination of mosquito species. Furthermore, mosquitoes were tested for the presence of R. felis DNA using a gltA-based FRET-qPCR, a nested-qPCR targeting the gltA of Rickettsia, and a R. felis species-specific BioB-based qPCR system. Domestic cat blood samples from 752 cats from 43 states and domestic dog blood samples from 777 dogs from 45 states of the USA were tested for the presence of R. felis DNA with the same PCR systems. Following Sanger sequencing, the sequences were analyzed and were submitted to the GenBank. After assigning the accession numbers, phylogenetic trees were constructed.
The AU-COI PCR system was validated which show sensitivity of a single copy of DNA/10 µL (Ae. japonicas, An. quadrimaculatus, Cx. nigripalpus, Cx. usquatissimus, Or. Alba, Ps. ferox, and Ur. sapphirina) and 10 copies/10 µL (An. punctipennis). Eight mosquito species were successfully identified by morphology, published PCR from Folmer et al. 1994, and the AU-COI PCR system. In addition, seven mosquito species were correctly identified by both of two PCR systems, but not by the morphology. Furthermore, nine mosquito species were only accurately identified by the AU-COI PCR, not by the published one or by the morphology. In this study, the AU-COI DNA barcoding method detected 24 mosquito species out of 128 individual mosquitoes, which included two new Culex and three new Psorophora species in Alabama.
Anopheles punctipennis, Aedes vexans and Uranotaenia sapphirina were found positive for R. felis. Molecular techniques detected R. felis in 9% of the mosquito pools. Nine percent (5/57) of the mosquito pools, including An. punctipennis (3/6), Ae. vexans (1/4) and Ur. sapphirina (1/3), were positive by PCR, in each case with all three Rickettsia specific PCRs. One of the positive An. punctipennis, and the positive Ur. sapphirina pool contained only male mosquitoes. The 120-bp nucleotide sequences of the five mosquito pools positive in R. felis-specific BioB-based PCRs were identical to one another, and to that of R. felis URRWXCal2. There was only a single base pair difference amongst the 446-bp nucleotide sequences of the positive gltA-based PCRs which were 99.7–100% identical to recognized R. felis strains in GenBank.
Four R. felis positive cats were from different states: Kansas, California, New York, and Texas, whereas three R. felis positive dogs were from Texas and Georgia. Low copy numbers of R. felis DNA (around 100 copies/ml whole blood) were found in four cats (4/752, 0.53%) and three dogs (3/777, 0.39%).
The DNA barcoding of mosquitoes is unaffected by morphological variation between different stages of the life cycle. This technology precisely identifies even the cryptic mosquitoes which is vital for the accuracy of a surveillance program as it greatly reduces the burden on experienced taxonomists. Results indicated the presence of R. felis in mosquitoes and in domestic cats and dogs in the USA. There is still much to be understood about the vector and reservoir role of the wide range of arthropods that harbor R. felis. The growing reports of R. felis occurring in mosquito species around the world and the known role of mosquitoes in transmitting a wide range of important human and animal pathogens indicate the necessity of further studies to determine the role mosquitoes play in the epidemiology of infectious diseases. The low levels of infection in clinically ill animals are consistent with R. felis being an unlikely cause of disease in naturally infected dogs and cats
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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