105,586 research outputs found
Quantification of food intake in Drosophila
No full textMeasurement of food intake in the fruit fly Drosophila melanogaster is often necessary for studies of behaviour, nutrition and drug administration. There is no reliable and agreed method for measuring food intake of flies in undisturbed, steady state, and normal culture conditions. We report such a method, based on measurement of feeding frequency by proboscis-extension, validated by short-term measurements of food dye intake. We used the method to demonstrate that (a) female flies feed more frequently than males, (b) flies feed more often when housed in larger groups and (c) fly feeding varies at different times of the day. We also show that alterations in food intake are not induced by dietary restriction or by a null mutation of the fly insulin receptor substrate chico. In contrast, mutation of takeout increases food intake by increasing feeding frequency while mutation of ovoD increases food intake by increasing the volume of food consumed per proboscis-extension. This approach provides a practical and reliable method for quantification of food intake in Drosophila under normal, undisturbed culture conditions
1628 Wertheim. Eine Stadt in Krieg und Hexenverfolgung
No full textRobert Meier: 1628 Wertheim. Eine Stadt in Krieg und Hexenverfolgung. Dettelbach: Verlag J. H. Röll 2014. 119 S. 14,95 Euro. Besprochen für die Mailingliste Hexenforschung von Klaus Graf. Von der ersten Juniwoche 1628 bis zur vierten Juniwoche 1630 werden Vorkommnisse in Wertheim am Main anhand der beneidenswert dichten Quellenüberlieferung im Staatsarchiv Wertheim in Form einer laufenden Chronik dokumentiert. Eingerahmt werden die mit genauen Quellennachweisen versehenen Beiträge von einem ..
Furious rabies after an atypical exposure.
No full textCitation: Wertheim, H. F. L. et al. (2009) 'Furious rabies after an atypical exposure', PLoS Medicine, 6(3): e1000044. [Available at http://medicine.plosjournals.org]. © 2009 Wertheim et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Der Wertheim-Bau
No full textDER WERTHEIM-BAU
Der Wertheim-Bau / Messel, Alfred (Public Domain) ( - )
Cover ( - )
Title page ( - )
Contents ( - )
Illustration: Tafel: 1. Detail des Mittelbaus der Facade. Bildhauer A. Vogel und W. Widemann ( - )
Illustration: Tafel: 2. Facade ( - )
Illustration: Tafel: 3. Oberer Theil des Mittelbaus der Facade ( - )
Illustration: Tafel: 4. Lichthof ( - )
Illustration: Tafel: 5. Lichthof mit Standbild der "Arbeit". Bildhauer Ludwig Manzel ( - )
Illustration: Tafel: 6. Ornament der Lichthofpfeiler. Bildhauer A. Vogel u. L. Manzel ( - )
Illustration: Tafel: 7. Stirnwand des Lichthofes. Maler Fritz Gehrke ( - )
Illustration: Tafel: 8. Stirnwand des Lichthofes. Maler Max Koch ( - )
Illustration: Tafel: 9. Detail des Vorraumes ( - )
Illustration: Tafel: 10. Decke des Vorraumes. Bildhauer Ernst Westphal ( - )
Illustration: Tafel: 11. Stützenbildung im Vorraume. Bildhauer G. Riegelmann ( - )
Illustration: Tafel: 12. Pfeiler des Vorraumes. Bildhauer G. Riegelmann ( - )
Illustration: Tafel: 13. Blick in den Teppichraum. Bildhauer Fritz Klimsch und H. Giesecke ( - )
Illustration: Tafel: 14. Teppichraum ( - )
Illustration: Tafel: 15. Fenster im Teppichraum. Maler Melchior Lechter ( - )
Illustration: Tafel: 16. Buffet des Erfrischungsraumes ( - )
Illustration: Tafel: 17. Abschluss des Erfrischungsraumes ( - )
Illustration: Tafel: 18. Fahrstuhlgitter. Kunstschmiedearbeiten von Schulz & Holdefleiss ( - )
Illustration: Tafel: 19. Geländerdetails. Kunstschmiedearbeiten von B. Muksits und Schulz & Holdefleiss ( - )
Illustration: Tafel: 20. Geländerdetails. Kunstschmiedearbeiten von Schulz & Holdefleiss ( - )
Illustration: Tafel: 22. Pfeilerkapitäl. Bildhauer H. Giesecke ( - )
Illustration: Tafel: 23. Stützenendigung. Bildhauer H. Giesecke ( - )
Illustration: Tafel: 24. Eingang in der Durchfahrt. Bildhauer Ernst Westphal ( - )
Illustration: Tafel: 25. Pfeiler im Teppichraum. Bildhauer H. Giesecke ( - )
Illustration: Tafel: 26. Facaden-Theil ( - )
Illustration: Tafel: 27 u. 28. Ornamentierung des Lichthofes und der Facade. Bildhauer A. Vogel u. W. Widemann ( - )
Illustration: 29. Grundriss des Erdgeschosses ( - )
Illustration: Tafel: 30. ( - )
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Artificial selection for nonreproductive host killing in a native parasitoid on the invasive pest, <i>Drosophila suzukii</i>
No full textEstablishment and spread of invasive species can be facilitated by lack of natural enemies in the invaded area. Host-range evolution of natural enemies augments their ability to reduce the impact of the invader and could enhance their value for biological control. We assessed the potential of the Drosophila parasitoid, Leptopilina heterotoma (Hymenoptera: Figitidae), to exploit the invasive pest Drosophila suzukii by focusing on three performance indices: (i) attack rate; (ii) host killing, consisting of killing rate and lethal attack rate (killing efficiency); and (iii) successful offspring development (reproductive success). We found significant intraspecific variation in attack rate and killing rate and lethal attack rate among seven European populations, but offspring generally failed to successfully develop from the D. suzukii host. We crossed these European lines to create a genetically variable source population and performed a half-sib analysis to quantify genetic variation. Using a Bayesian animal model, we found that attack rate and killing rate had a heritability of h(2)=0.2, lethal attack rate h(2)=0.4, and offspring development h(2)=0. We then artificially selected wasps with the highest killing rate of D. suzukii for seven generations to test whether host-killing could be improved. There was a small and inconsistent response to selection in the three selection lines. Realized heritability (hr(2)) after four generations of selection was 0.17 but near zero after seven generations of selection. The genetic response might have been masked by an increased D. suzukii fitness resulting from adaptation to laboratory conditions. Our study reveals that native, European, L. heterotoma can attack the invasive pest, D. suzukii and significantly reduce fly survival and that different steps of the parasitization process need to be considered in the evolution of host-range. It highlights how evolutionary principles can be applied to optimize performance of native species for biological control.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Behavioural plasticity in support of a benefit for aggregation pheromone use in Drosophila melanogaster
No full textWe explored behavioural plasticity in the use of aggregation pheromone in the fruit fly Drosophila melanogaster Meigen (Diptera: Drosophilidae). Based on previous field observations, we formulated two hypotheses on a benefit of using aggregation pheromone for aggregated oviposition. One hypothesis concerns a benefit to the females themselves, where reduced harassment by males can enhance oviposition rate; the other concerns a benefit to their offspring, where larvae can exploit arduous substrates more efficiently. We derive contrasting expectations on the strength of the behavioural response to pheromone for substrates that differ in nutritional quality to larvae. High quality substrates relax the strength of larval competition, which allows for stronger aggregative responses of the females, but conversely, it may yield aggregation less necessary when the benefit is related to resource exploitation by the larvae. In indoor and outdoor dual choice set-ups, we tested the behavioural responses of the adults to the aggregation pheromone with substrates of varying quality, and examined oviposition behaviour. The response of adults to the aggregation pheromone was strong and robust for low quality substrates, but significantly weaker for a high quality substrate. This supports the hypothesis on a benefit to the larvae. Females retained aggregation pheromones in the absence of oviposition substrates for at least 24 h. In the outdoor set-up, substrate with aggregation pheromone received more than three times as many eggs as control substrates, and this was directly related to the number of adults that visited each substrate. Per capita, oviposition rates were not different for differently sized aggregations, and consequently, no evidence was found in support of the hypothesis on reduced harassment. The combination of aggregation pheromone possession and a mutualistic relationship with micro-organisms for Drosophila and other insects is discussed.
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe 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
No full textWe 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
The construction of Karen Karnak: The multi-author-function
No full textThis thesis is situated within the comparatively recent developments of Web 2.0 and the emergence of interactive WikiMedia, and explores the mode of authorship within a Read/Write culture compared to that of a Read/Only tradition. The hypothesis of this study is that the role of the audience has become merged with the author, and as such, represents new functions and attributes, distinct from a more conventional concept of authorship, in which the roles of audience and author are more separate. Read/Write and participatory culture, as defined by this study, is focused on collaboration, and includes the influences of D.I.Y. culture, Open-Source practices and the production of text by multiple authors. Multi-authorship presents a re-thinking of several concepts which support the notion of the individual author, since the focus of multi-authorship is not on attribution and ownership of a finished text, but on the continued malleability of a text. Modes of multi-authorship, demonstrated in the use of the pseudonyms Alan Smithee and Karen Eliot, represent declarative authors whose names signify multiple origins, whilst concurrently indicating a distinct body of work. The function of these names form an important context to this study, since primary research involves the construction of an experimental mode of multi-authorship utilising WikiMedia technology and the interaction of thirty nine participants, who are invited to create a body of work under the collective pseudonym Karen Karnak. The data generated by this experiment is analysed using aspects of Michel Foucault's author-function to identify and determine power structures inherent in the WikiMedia context. The interplay of power structures, including concepts such as identity, ownership and the body of work, affect the resulting mode of authorship and contribute to the construction of Karen Karnak, suggesting further areas of research into the emerging multi-author
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