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    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

    Toxicity of anethole and its effects on egg production of Ceratitis capitata Wied. (Dipt., tephritidae)

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    We report the effects of anethole on adult Ceratitis capitata Wied. (Diptera, Tephritidae) which cause serious damage to fruit crops. Because of the toxicological and environmental pollution due to the indiscriminate use of organophosphates against the endophagous larvae, the control of this pest is now mainly directed against the adults, by the application of bait sprays. Considerable toxic effects have been obtained by oral administration to adults of nutritive formulations containing 5% anethole with some hydrolised commercial proteins. In this test we observed high values of mortality (85% after 24 h) and a total inhibition of reproductive activity. The toxic effect produced by oral administration of the compound tested appears to be correlated to irreversible damage to the gut of the medfly. These results acquire a particular importance in view of the introduction of alternative methods for the control of the medfly. In particular, our objective is the testing of relevant formulations of this active principle in field. The use of anethole combined with protein baits, which can be used in the open field, is therefore particularly promising

    Effects of essential oil formulations on Ceratitis capitata Wied. (Dipt., Tephritidae) adult flies

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    The effects on adult Ceratitis capitata of the ingestion of formulations containing different concentrations of some essential oils were examined. The bioassays were carried out using groups of C. capitata adults fed for 3 days with formulations containing a known concentration (0.25%, 0.5%, 1.0%) of essential oils. The oils, of different chemical composition, were obtained by steam distillation from aromatic plants collected during the balmy period. The essential oils of Rosmarinus officinalis and Salvia officinalis, which are rich in monoterpenic hydrocarbons and monoterpenic ketones, respectively, showed poor activity, whereas the oils of Cinnamomum zeylanicum and Thymus sp. showed a marked toxic effects (over 90% mortality after 72 h). This could be explained by the activity of cinnamic aldehyde (about 80% of the Cinnamomum oil) and carvacrol (68% of Tit. capitatus oil and about 45% of Th. herba barona oil). The first consequence of ingesting even small quantities of essential oils was a depressive effect on the nervous system. Dissection of dead flies showed marked differences compared with the controls and microscopic examination revealed anomalies in the gut region
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