130,719 research outputs found
Data and code from: No sex difference in preen oil chemical composition during incubation in Kentish plovers
No full textGilles M, Kosztolányi A, Rocha AD, Cuthill IC, Székely T, Caspers B. Data and code from: No sex difference in preen oil chemical composition during incubation in Kentish plovers. Bielefeld University; 2024.## Data and code from: No sex difference in preen oil chemical composition during incubation in Kentish plovers
##### Marc Gilles, András Kosztolányi, Afonso D. Rocha, Innes C. Cuthill, Tamás Székely & Barbara A. Caspers
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### Overview of the repository content
* **`Raw chromatographic data.zip`** is a compressed folder containing the raw chromatograms.
* **`chemdata.csv`** contains the chemical (chromatographic) data of the preen oil samples.
* **`metadata.csv`** contains the metadata of the preen oil samples.
* **`metadata_description.xlsx`** describes the variables of the metadata.
* **`Rcode.pdf`** and **`Rcode.Rmd`** contain the R code used for the analyses
No sex difference in preen oil chemical composition during incubation in Kentish plovers
No full textPreen oil – the secretion from the uropygial gland of birds – may have a specific function in incubation. Consistent with this, during incubation, the chemical composition of preen oil is more likely to differ between sexes in species where only one sex incubates than in species where both sexes incubate. In this study, we tested the generality of this apparent difference, by investigating sex differences in the preen oil composition of a shorebird species, the Kentish plover (Anarhynchus, formerly Charadrius, alexandrinus). As both sexes incubate in this species, we predicted the absence of sex differences in preen oil composition during incubation. In the field, we sampled preen oil from 9 females and 11 males during incubation, which we analysed with gas chromatography–mass spectrometry (GC–MS). Consistent with predictions, we found no sex difference in preen oil composition, neither in beta diversity (Bray-Curtis dissimilarities) nor in alpha diversity (Shannon index and number of substances). Based on these results, we cannot conclude whether preen oil has a function during incubation in Kentish plovers. Still, we discuss hypothetical roles, such as olfactory crypsis, protection against ectoparasites or olfactory intraspecific communication, which remain to be tested
Parental role division predicts avian preen wax cycles
No full textPrevious studies have shown that preen wax composition in some sandpipers shifts from the usual monoesters to diesters during the breeding season, possibly to reduce the ability of mammalian predators to find nests using olfactory cues. To investigate further the relationship between incubation and wax secretion, we examined seven sandpiper species with different incubation patterns (species in which both sexes incubate, in which only males incubate and in which only females incubate). During the breeding period, diester preen wax was secreted almost exclusively by the incubating sex in species with uniparental incubation, and by both sexes in species with biparental incubation. These findings suggest that diester preen waxes have a function that is directly related to incubation. Unexpectedly, in female-incubating Curlew Sandpiper Calidris ferruginea and Buff-breasted Sandpiper Tryngites subruficollis, some males also secreted diester preen waxes during the breeding period. This suggests that some males may in fact incubate, that these waxes may be a remnant from their evolutionary past when both sexes incubated, or that males need to be olfactorally cryptic because they are involved in the making of nest scrapes. The seasonal pattern of preen wax composition was also studied in captive male, female and female-mimicking male (`faeder¿) Ruff Philomachus pugnax. Captive female Ruff changed preen wax composition from monoesters to diesters in the spring despite the fact that no incubation took place. This suggests that circannual rhythms rather than actual incubation behaviour may trigger the shift to diester waxes. All captive male Ruff, including the faeders, continued to secrete monoesters, supporting the hypothesis that only the incubating sex secretes diesters
No sex difference in preen oil chemical composition during incubation in Kentish plovers
No full textGilles M, Kosztolányi A, Rocha AD, Cuthill IC, Szekely T, Caspers B. No sex difference in preen oil chemical composition during incubation in Kentish plovers. PeerJ. 2024;12: e17243.Preen oil, the secretion from the uropygial gland of birds, may have a specific function in incubation. Consistent with this, during incubation, the chemical composition of preen oil is more likely to differ between sexes in species where only one sex incubates than in species where both sexes incubate. In this study, we tested the generality of this apparent difference, by investigating sex differences in the preen oil composition of a shorebird species, the Kentish plover (Anarhynchus, formerlyCharadrius,alexandrinus). As both sexes incubate in this species, we predicted the absence of sex differences in preen oil composition during incubation. In the field, we sampled preen oil from nine females and 11 males during incubation, which we analysed with gas chromatography–mass spectrometry (GC–MS). Consistent with predictions, we found no sex difference in preen oil composition, neither in beta diversity (Bray-Curtis dissimilarities) nor in alpha diversity (Shannon index and number of substances). Based on these results, we cannot conclude whether preen oil has a function during incubation in Kentish plovers. Still, we discuss hypothetical roles, such as olfactory crypsis, protection against ectoparasites or olfactory intraspecific communication, which remain to be tested
Scatter plots between total PCB concentration in the plasma samples and black-footed albatross adults (A) and chicks (B) body mass, between total PCB concentration in the preen oil samples and black-footed albatross adults body mass (C), and between total PCB concentration in the plasma and preen oil samples (D).
No full text<p>Scatter plots between total PCB concentration in the plasma samples and black-footed albatross adults (A) and chicks (B) body mass, between total PCB concentration in the preen oil samples and black-footed albatross adults body mass (C), and between total PCB concentration in the plasma and preen oil samples (D).</p
Design Mining Microbial Fuel Cell Cascades
No full textMicrobial fuel cells (MFCs) perform wastewater treatment and electricity
production through the conversion of organic matter using microorganisms. For
practical applications, it has been suggested that greater efficiency can be
achieved by arranging multiple MFC units into physical stacks in a cascade with
feedstock flowing sequentially between units. In this paper, we investigate the
use of computational intelligence to physically explore and optimise
(potentially) heterogeneous MFC designs in a cascade, i.e. without simulation.
Conductive structures are 3-D printed and inserted into the anodic chamber of
each MFC unit, augmenting a carbon fibre veil anode and affecting the
hydrodynamics, including the feedstock volume and hydraulic retention time, as
well as providing unique habitats for microbial colonisation. We show that it
is possible to use design mining to identify new conductive inserts that
increase both the cascade power output and power density
Intraspecific preen oil odor preferences in dark-eyed juncos (Junco hyemalis)
No full textAbstract Most birds possess a uropygial gland that produces a secretion, preen oil, that contains volatile compounds that may transmit information about individual attributes. However, the ability of passerine songbirds to discriminate among the odors of different individuals has not yet been demonstrated. We tested whether dark-eyed juncos (Junco hyemalis) could discriminate among preen oil odors from 1) conspecifics and heterospecifics; 2) male and female conspecifics; 3) conspecifics from same or different population or subspecies; and 4) males with large or small plumage ornaments. Our evidence suggests that juncos can discriminate between the odor of conspecifics and heterospecifics. In 2-way choice tests between conspecific odors, both males and females spent more time with male preen oil. Subjects did not discriminate between odors of individuals from their own population or a different one, and no relationship was found between choice and plumage ornaments. Unexpectedly, females spent more time with the odor of males with smaller body size, regardless of population of origin. This result was especially surprising because an analysis of preen oil volatile compounds revealed that the odors of smaller males were less "male-like" than the odors of larger males. We conclude that songbirds are able to detect odors from preen oil as shown by their ability to distinguish odors arising from males and females. They may also be able to distinguish among individuals of varying body size
Intraspecific preen oil odor preferences in dark-eyed juncos (Junco hyemalis)
No full textMost birds possess a uropygial gland that produces a secretion, preen oil, that contains volatile compounds that may transmit information about individual attributes. However, the ability of passerine songbirds to discriminate among the odors of different individuals has not yet been demonstrated. We tested whether dark-eyed juncos (Junco hyemalis) could discriminate among preen oil odors from 1) conspecifics and heterospecifics; 2) male and female conspecifics; 3) conspecifics from same or different population or subspecies; and 4) males with large or small plumage ornaments. Our evidence suggests that juncos can discriminate between the odor of conspecifics and heterospecifics. In 2-way choice tests between conspecific odors, both males and females spent more time with male preen oil. Subjects did not discriminate between odors of individuals from their own population or a different one, and no relationship was found between choice and plumage ornaments. Unexpectedly, females spent more time with the odor of males with smaller body size, regardless of population of origin. This result was especially surprising because an analysis of preen oil volatile compounds revealed that the odors of smaller males were less "male-like" than the odors of larger males. We conclude that songbirds are able to detect odors from preen oil as shown by their ability to distinguish odors arising from males and females. They may also be able to distinguish among individuals of varying body size. Copyright 2011, Oxford University Press.
MeSH term explosion and author rank improve expert recommendations
No full textInformation overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
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
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