1,720,970 research outputs found
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
Age-related changes in cuticular hydrocarbon bouquet and same-sex sexual behavior of mason bee males (Osmia bicornis and O. cornuta) (Dataset)
No full textFinding a mate is the central task in the lives of many male insects. In many solitary bees, sexual competition between males is high due to monandry and a pronounced male-biased sex ratio. Males searching for females will inspect and mount any object of suitable size and habitus. Species, sex, and reproductive status are encoded in the bee’s bouquet of cuticular hydrocarbons (CHCs) and can only be identified at a short distance from the object encountered. In two species of mason bees, this CHC-based system for recognizing newly emerged, virgin females is not error-free. Newly emerged individuals of both sexes carry similar CHC bouquets, facilitating the confusion of newly emerged males with newly emerged, virgin females. Misidentification leads to same-sex sexual behavior by males seeking a mate. However, individuals of both sexes modify their CHC bouquet sex-specifically within a few days. The changes in the bouquet prevent further sexual harassment. In addition, within three days of emergence, males begin to release species-specific carboxylic acid esters, which may act as courtship-inhibiting pheromones to extend the range of their sex-specific scent tag. Due to the pronounced protandry of both species, SSB is restricted to the early flight season, when females are not yet present, and imposes no apparent cost on the two males involved
Territoriality is just an option: allocation of a resource fundamental to the resource defense polygyny in the European wool carder bee, Anthidium manicatum (Hymenoptera: Megachilidae) (Dataset)
No full textThe wool carder bee Anthidium manicatum is one textbook example of resource defense polygyny among solitary bees, known for intense male–male competition, forced copulations, and the extreme form of interspecific territoriality toward other flower visitors. This mating system depends on the spatial structure of the defended resource and requires several adaptations in males. The allocation of patches with host plants as well as male body size and phenology was analyzed over 3 years in the diverse habitat of a botanical garden. Anthidium manicatum males searched in groups up to 12 individuals a wide diversity of patches with various food plants of foraging females. Territories were established in small high-quality patches only. Males abandoned aggressive and territorial behavior in large patches. Available patches were occupied by males of the various body size fractions independently of each other according to patch profitability. The higher competitive weight of large males in small patches compared to spacious ones was balanced by an opposing correlation of patch profitability. Although the mating system in A. manicatum is clearly a resource defense polygyny, males were found to be plastic in their behavior, and territoriality was not consistently observed. Mate acquiring tactics, be they territory holder (bourgeois), sneaker, floater, or scrambler for mating, can be considered to be different behavioral phenotypes within one environmentally sensitive conditional strategy
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
Age‑related changes in cuticular hydrocarbon bouquet and same‑sex sexual behavior of mason bee males (Osmia cornuta and O. bicornis)
Get PDFFinding a mate is the central task in the lives of many male insects. In many solitary bees, sexual competition between males is high due to monandry and a pronounced male-biased sex ratio. Males searching for females will inspect and mount any object of suitable size and habitus. Species, sex, and reproductive status are encoded in the bee’s bouquet of cuticular hydrocarbons (CHCs) and can only be identified at a short distance from the object encountered. In two species of mason bees, this CHC-based system for recognizing newly emerged, virgin females is not error-free. Newly emerged individuals of both sexes carry similar CHC bouquets, facilitating the confusion of newly emerged males with newly emerged, virgin females. Misidentification leads to same-sex sexual behavior by males seeking a mate. However, individuals of both sexes modify their CHC bouquet sex-specifically within a few days. The changes in the bouquet prevent further sexual harassment. In addition, within 3 days of emergence, males begin to release species-specific carboxylic acid esters, which may act as courtship-inhibiting pheromones to extend the range of their sex-specific scent tag. Due to the pronounced protandry of both species, SSB is restricted to the early flight season, when females are not yet present, and imposes no apparent cost on the two males involved
Die Parasitierung der Luzerne-Blattschneiderbiene, \u3ci\u3eMegachile rotundata\u3c/i\u3e (Hymenoptera: Megachilidae), durch \u3ci\u3ePhysocephala pusilla\u3c/i\u3e (Diptera: Conopidae) in der Mongolei = Parasitization of the Alfalfa Leaf-Cutter Bee, \u3ci\u3eMegachile rotundata\u3c/i\u3e (Hymenoptera: Megachilidae), by \u3ci\u3ePhysocephala pusilla\u3c/i\u3e (Diptera: Conopidae) in Mongolia
Get PDFPhysocephala pusilla Meigen (Diptera: Conopidae) was found to be a dangerous endoparasitoid of the alfalfa leafcutter bee Megachile rotundata F. (Hymenoptera: Megachilidae) in Mongolia. The conopid fly parasitizes adults and causes their early death. In 1989 and 1990, 16% and 15% respectively of the M. rotundata females were found dead in front of the bee shelter. However, the number of bees (females and males) dying in the field is unknown. These bees cause a contamination of the alfalfa fields due to an increase of the conopid population. Therefore, Ph. pusilla becomes a serious problem for the management of M. rotundata in Mongolia. The control of the conopid fly might be complicated due to the synchronization of their developmental cycles with that of the host and the contamination of the fields by perished parasitized bees. The discovery of a autochthony hyperparasite, Pteromalus conopidarum Bouček (Hymenoptera: Pteromalidae), in pupariums of the parasite opens the possibility of a biological pest control
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