1,720,960 research outputs found
The evaluation of Beauveria isolates for virulence to diamondback moth (Plutella xylostella L.) : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Horticultural Science at Lincoln University
Get PDFBeauveria is a genus of entomopathogenic fungi that exhibits traits suitable for the development of commercial biopesticide products to control various arthropod pests, as well as plant pathogens. The literature describes thousands of strains of Beauveria, largely limited to strains of Beauveria bassiana that have been isolated and screened for their ability to control pests around the world. Some of these pests, such as diamondback moth (DBM), the two-spotted spider mite, green peach aphid and housefly, are highly resistant to chemical insecticides. This study was conducted to find at least one New Zealand derived Beauveria isolate able to control DBM. The first question of this study was, “do other Beauveria species have the potential to control DBM”? Thus, 14 isolates from four Beauveria species were assessed for their control of DBM under in vitro conditions. Before the assessment, all 14 isolates were taxonomically identified using both morphological and DNA-based methods. The in vitro bioassays identified three isolates of B. bassiana (Mo1, CTL20, and CTA20) and B. pseudobassiana (FRhp, FW Mana, and I12 Damo) that successfully killed 50% of the DBM larvae (median lethal dose LD50) at a low dosage while isolates from two other species could not achieve LD50 at a higher rate. This is the first report that details B. pseudobassiana as a potential species for DBM control.
Combining two or more fungal isolates may improve the efficacy of a biological control agent. The second question examined was, “do combinations of Beauveria isolates result in a synergistic or an antagonistic interaction”? Beauveria isolates were grouped according to their previously assessed virulence towards DBM. Under in vitro conditions, combining the low virulent isolates together resulted in a higher and faster DBM mortality rate than when these isolates were applied separately. Combining the three species of Beauveria together resulted in antagonistic interactions between the fungi, with lower mortality rates than when these isolates were applied separately.
Diet can sometimes affect the susceptibility of an insect to entomopathogenic fungi. The third question of this study was “is there any difference in the susceptibility of DBM larvae to fungal infection by selected Beauveria isolates when raised on different brassicas”? DBM larvae were fed on four different brassicas with predicted high (broccoli and cabbage) and low (cauliflower and radish) glucosinolate levels. Glucosinolates have been implicated in the resistance of brassica hosts to plant pathogens. In vitro results showed that DBM larvae fed on broccoli and cabbage were more susceptible to infection by B. pseudobassiana I12 Damo than larvae raised on cauliflower and radish. Conversely, DBM larvae raised on cauliflower and radish were more susceptible to infection by B. bassiana CTL20 than larvae fed on broccoli and cabbage.
Secondary metabolites produced by Beauveria spp. have previously been found to have insecticidal properties and can kill a wide range of insects, including DBM. The fourth question investigated was, “was there evidence that an isolate of Beauveria spp. produces toxins that kill DBM larvae directly”? B. pseudobassiana FW Mana was selected as it caused high DBM mortality in previous bioassays but exhibited less sporulation from DBM cadavers compared to the other isolates within the study. The filtered supernatant of B. pseudobassiana FW Mana was used for assays along with toxins from two other less-lethal isolates of Beauveria. As expected, the supernatant from B. pseudobassiana FW Mana caused significantly higher mortality than the supernatant from the other two isolates assessed. Overall, this study found several Beauveria isolates that have the potential to be developed and commercialised as biopesticides to control DBM
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
- …
