1,720,989 research outputs found
Employing **Macrolophus pygmaeus** as natural enemy against sweet pepper key pests in practice
No full textAbstract: Biologische bestrijding van plagen is een succesverhaal in de Europese paprikateelt onder glas en de meeste plagen worden onder controle gehouden door het uitzetten van natuurlijke vijanden. Bladluizen vormen echter nog steeds een groot probleem en de gespecialiseerde bladluispredatoren die uitgezet worden, blijken vaak niet in staat om de plaag onder controle te krijgen waardoor men chemisch ingrijpt. Maar door hun hoge voortplantingssnelheid en korte generatietijd zijn bladluizen in staat zeer snel resistentie te ontwikkelen tegen verschillende insecticiden. Tegenwoordig is er meer aandacht voor het gebruik van generalisten in plaagbestrijding omdat zij ook in het gewas kunnen overleven als er geen plagen zijn. Macrolophus pygmaeus is een generalistische roofwants die reeds veelvuldig wordt ingezet in Europese tomatenserres tegen diverse plagen. In dit doctoraatsonderzoek werd het gebruik van M. pygmaeus in paprikateelt onderzocht. Allereerst werden uitzetstrategie\uebn met betrekking tot bijvoederen getest. Niet alle generalisten hebben nood aan bijvoederen en verschillende voedseltypes of bijvoederstrategie\uebn kunnen de populatiegroei en verspreiding in het gewas be\uefnvloeden. Tweewekelijks vollevelds bijvoederen met cysten van pekelkreeftjes bleek de beste strategie voor de vestiging van M. pygmaeus in paprika. Vervolgens werd onderzocht of de roofwantsen in staat zijn om twee belangrijke plagen in paprika, bladluizen en tripsen, te bestrijden. Het effect van M. pygmaeus op bladluisbestrijding werd bestudeerd in combinatie met het wegsnijden van bladeren tot op verschillende hoogtes. Dit verkleint de verticale lengte van het gebladerte en brengt zo prooi en predator dichter bij elkaar. Bij een lengte korter dan 190 cm konden de roofwantsen bladluizen succesvol bestrijden. Californische trips wordt momenteel bestreden door het uitzetten van de roofwants Orius laevigatus. Maar M. pygmaeus voedt zich ook met tripsen en kan zo O. laevigatus overbodig maken. Tijdens de drie seizoen van experimenten was M. pygmaeus op zichzelf in staat om trips onder controle te houden. Deze trips en M. pygmaeus data werden vervolgens gebruikt om prooi-predator modellen op te stellen die op basis van wekelijkse monitoringdata de kans op plaagcontrole voorspellen in de komende week. Met onze bevindingen kan M. pygmaeus succesvol ingezet worden voor plaagbestrijding in paprikaserres en telers verder op weg helpen naar een pesticiden-arme of zelfs pesticiden-vrije paprikateelt
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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