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Schwabl, Hubert
No full textHubert Schwabl, field ecologist, 1993
Photo by Robert Reicherthttps://digitalcommons.rockefeller.edu/scientific-staff/1054/thumbnail.jp
OVARIAN PHYSIOLOGY IN A NON-DOMESTICATED BIRD: MECHANISMS BEHIND THE ACCUMULATION AND VARIATION OF YOLK ANDROGENS IN HOUSE SPARROWS
Get PDFThesis (Ph.D.), Zoology, Washington State UniversityIn birds and other oviparous species, the accumulation of maternally-derived yolk androgens may represent an adaptive transgenerational information system. Researchers have found multiple effects of these yolk androgens on offspring in diverse oviparous species, in addition to many social and environmental factors that act on females to alter their yolk androgen levels. What is missing, however, is an understanding of the mechanism by which androgens accumulate in yolk, as well as knowledge of the physiological cause(s) of the immense intra-specific variation in yolk androgens. Using the drug tamoxifen to reduce levels of vitellogenin yolk precursors in house sparrows (Zoology, Washington State Universit
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
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
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Immune function and development in altricial-developing passerine house sparrows (Passer domesticus)
Get PDFPasserine birds are known to be ecologically, agriculturally, and environmentally relevant fixtures on six of the seven world continents and yet the immune systems for these altricial-developing species are poorly defined. We profiled the early humoral development of the adaptive immune system in an altricial-developing wild passerine species, the house sparrow (Passer domestics) and characterized the half-life of maternal antibodies in nestling plasma, the onset of de novo synthesis of endogenous antibodies by nestlings, and the timing of immunological independence, where nestlings rely entirely on their own antibodies for immunologic protection. We developed assays to measure both antigen-specific and total antibody concentration in the plasma of females, yolks, and nestlings and traced the transfer of maternal antibodies from females to nestlings through the yolk. Based on the short half-life of maternal antibodies, the rapid production of endogenous antibodies by nestlings and the relatively low transfer of maternal antibodies to nestlings, our findings suggest that 1) altricial-developing sparrows achieve immunologic independence much earlier than precocial chickens and 2) maternal antibodies may not confer the immunologic protection or immune priming previously proposed in other passerine studies. Maternal antibodies are believed to protect immunologically immature avian offspring during the critical period between hatch and the onset of endogenous antibody production. Yet, as aforementioned, house-sparrow specific patterns of immunity suggest that maternal antibodies may play a limited role in protecting and priming immunologically na ve young against environmental pathogens. We tested the ability of female house sparrows to influence the immunologic phenotype of their offspring s humoral immune system through the transfer of antigen-specific maternal antibodies and found no effect of maternal antibodies on nestling body condition or immunity. Our results suggest that maternal antibodies may be a neutral byproduct of the female immune system more so than a reflection of adaptive maternal investment. Further research needs to be conducted on other altricial passerines to determine if the results of our study are a species-specific phenomenon or if they can be applied to other avian species
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
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