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The accessory glands of the female reproductive system of Ceratitis capitata Wied. (Diptera): an updated review
No full textIn general, females of insects have two ectodermic organs connected with the genital chamber. One is the spermatheca, typically opening at the anterior of such a chamber and serving as storage for spermatozoa to be used for fertilizing eggs. The other organs are the accessory glands opening more posteriorly and serving for several functions in the different insect orders (DAVEY, 1985; GILLOT, 1996). In the medfly the accessory glands, which have been ultrastructurally studied in recent years (DALLAI et al., 1985; 1988), flow their secretions on the anterior dorsal region of the bursa copulatrix at the same site of the spermathecal duct openings. We summarize the results obtained on the fine structure of the accessory glands and on the biochemical and molecular characterization of the secretions produced by these organs. Particularly, ceratotoxins are antibacterial peptides identified in the Ceratitis accessory gland secretions (MARCHINI et al., 1993; 1995; ROSETTO et al., 1996; ROSETTO et al., 1997). As the maximum expression of such peptides overlaps the female sexual maturity, it was hypotesized that their presence in the female genital ducts might ensure the realization of the proper environmental conditions for fertilization avoiding bacterial infections which could interfere with the sperm-egg interaction. Moreover, the finding of this antimicrobial material on the chorion of laid eggs raises the possibility that these substances play some specific role in the oviposition site, possibly protecting the eggs and the young larvae from environmental injuries (MARCHINI et al., 1997)
Structure and biochemical properties of outer arm dynein from sperm axonemes of two insect species.
No full textBiological Control of the medfly Ceratitis capitata using molecular biology techniques. Controllo biologico della mosca mediterranea della frutta Ceratitis capitata mediante l'uso di tecniche biomolecolari
No full textWe show biochemical and molecular biology studies on the female reproductive accessory gland secretion from Ceratitis capitata wild flies of different origin. The gland secretions from all the populations we analyzed share the same electrophoretic pattern and the antibacterial female-specific peptides ceratotoxins, previously characterized by our research group, are found in all the populations. Southern blot analysis shows that the ceratotoxin genes share the same genomic organization in all the populations. Therefore, we can consider the use of ceratotoxin promoters to control the reproduction of C. capitata natural populations
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
The sex-specific ceratotoxin genes: a possible model for transgenesis in the medfly Ceratitis capitata
No full textCaratterizzazione molecolare di una lipasi espressa nelle ghiandole accessorie all'apparato riproduttore femminile di Phlebotomus papatasi (Diptera: Psychodidae)
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