6,259 research outputs found
Extrapair paternity and the evolution of bird song
No full textBird song is usually considered to have evolved in the context of sexual selection. Because extrapair paternity is a major component of sexual selection, mating advantages at the social level for males that produce songs of high quality may be transformed into higher success in extrapair paternity. Therefore, males with longer and more complex songs should suffer less from extrapair paternity intraspecifically, whereas species with high rates of extrapair paternity, reflecting intense sperm competition, should produce more elaborate songs. Although some intraspecific studies demonstrated a negative link between features of songs and extrapair paternity in own nest, others failed to detect such a relationship. Contrary to expectation, a meta-analysis of all studies revealed no significant intraspecific evidence for songs being associated with extrapair paternity. In addition, in comparative analyses based on generalized least squares (GLS) models, we found that no measures of song complexity and temporal output were significantly related to extrapair paternity interspecifically, even when potentially confounding factors such as social mating system, life history, migration, habitat, or sexual dichromatism were held constant. Only plumage dichromatism was significantly related to extrapair paternity. The absence of both intra- and interspecific relationships between measures of song variability and extrapair paternity suggests that factors other than postmating sexual selection have been the important evolutionary forces shaping differences in song. Copyright 2004.bird song; evolution; extrapair paternity; generalized least squares; meta-analysis; repertoire size; sexual selection
Immune challenge mediates vocal communication in a passerine bird: an experiment
No full textSecondary sexual characters may have evolved in part to signal resistance to parasites. Avian song has been hypothesized to be involved in this process, but the role of parasites in modulating acoustic communication systems in birds remains largely unknown, owing to lack of experiments. We studied the relationship between parasitism, testosterone, song performance, and mating success in male collared flycatchers (Ficedula albicollis) by experimentally challenging their immune system with a novel antigen. We predicted that a challenge of the immune system would reduce song performance, and that this reduction would be conditional on the size of a visual sexual signal, the forehead patch that was previously found to reflect resistance. An antagonistic linkage between testosterone and immune function would predict that a challenge of the immune system should suppress testosterone level. An immunological treatment by sheep red blood cells (SRBCs) triggered a decrease in body mass, testosterone level, and song rate, but other song traits were not significantly affected by the antigen challenge. Initial testosterone level was associated with forehead patch size and all song traits except song rate. SRBC injection caused stronger reduction in song rate among males with smaller forehead patches, and the change in song rate was also predictable by song features such as strophe complexity and length. We show that song rate and other song characteristics may be important cues in male-male competition and female choice. These results suggest that parasite-mediated sexual selection has contributed in shaping a complex acoustic communication system in the collared flycatcher, and that testosterone may play an important role in this process. Parasitism may drive a multiple signaling mechanism involving acoustic and visual traits with different signal function. Copyright 2004.bird song; collared flycatcher; immunocompetence; parasites; secondary sexual characters; testosterone
Protein-heme interactions in hemoglobin from the mollusc Scapharca inaequivalvis: evidence from resonance Raman scattering.
No full textMetastable CO binding sites in the photoproduct of a novel cooperative dimeric hemoglobin.
No full textThe infrared absorption spectrum of the CO-photoproduct from Scapharca inaequivalvis hemoglobin (Hbl) at 10 K yields only a single line in the "B" state region at 2132 cm-1. This is the same frequency as the B1 line observed in photodissociated vertebrate HbCO and MbCO. No evidence was found for the B2 line detected in vertebrate hemoglobins and myoglobin in the 21182120 cm-1 region. These data demonstrate that the protein does not have the same conformationally accessible ligand-binding sites as do vertebrate hemoglobins and myoglobins. The absence of the B2 line indicates that only a single weak site is accessible to the photolyzed CO molecule. These results are in accord with geminate rebinding experiments and ligand escape pathway calculations which have shown that the distal properties of Hbl are distinct from those of tetrameric hemoglobins and vertebrate myoglobins
Heme-heme interactions in a homodimeric cooperative hemoglobin. Evidence from transient Raman scattering.
No full textStructural requirements of mastoparan for activation of membrane-bound guanylate-cyclase.
No full textUtilising Deep Learning Models for the Surface Registration Problem in HoloNav
No full textSurface Registration is a registration problem that handles the registration of two similar surfaces. In most research that utilises Deep Learning (DL) models to handle surface registration two theories are investigated; the first being whether surfaces sampled from the same origin can be registered together, and the second theory being whether the models can register Point Clouds with low overlapping data for utilisation in Simultaneous Localisation and Mapping (SLAM) applications. However, the surface registration to be utilised in the HoloNav Augmented Reality (AR) navigation system will utilise Point Clouds sampled from different origins with a high overlap ratio. This research, therefore, aims to determine the viability of DL methods for surface registration in HoloNav data. To determine the viability, rotation and translation errors in the match were used, with the aforementioned metrics later being evaluated manually with the utilisation of a visualiser. The results indicate that the models can generalise on the navigator data for an initial Euler angle difference of 45 degrees, but due to the difference in sampling density on the utilised point clouds can not provide accurate matches. Therefore, the utilisation of DL models can be considered to be viable if the navigator data has a sampling density similar to the pre-operative model.https://github.com/alpcicimen/holonav-dl-registration The link to the github repository containing the utilised dataset, scripts, as well as the modified DL models RPMNet and PREDATOR.CSE3000 Research ProjectComputer Science and Engineerin
The Scent of a Smell: An Extensive Comparison between Textual and Structural Smells
No full textCode smells are symptoms of poor design or implementation choices that have a negative effect on several aspects of software maintenance and evolution, such as program comprehension or change- and fault-proneness. This is why researchers have spent a lot of effort on devising methods that help developers to automatically detect them in source code. Almost all the techniques presented in literature are based on the analysis of structural properties extracted from source code, although alternative sources of information (e.g., textual analysis) for code smell detection have also been recently investigated. Nevertheless, some studies have indicated that code smells detected by existing tools based on the analysis of structural properties are generally ignored (and thus not refactored) by the developers. In this paper, we aim at understanding whether code smells detected using textual analysis are perceived and refactored by developers in the same or different way than code smells detected through structural analysis. To this aim, we set up two different experiments. We have first carried out a software repository mining study to analyze how developers act on textually or structurally detected code smells. Subsequently, we have conducted a user study with industrial developers and quality experts in order to qualitatively analyze how they perceive code smells identified using the two different sources of information. Results indicate that textually detected code smells are easier to identify and for this reason they are considered easier to refactor with respect to code smells detected using structural properties. On the other hand, the latter are often perceived as more severe, but more difficult to exactly identify and remove.Accepted Author ManuscriptSoftware Engineerin
The Song of Solomon in the Dialect of Cumberland
Full text linkLiteratura dialectal inglesa. -- Cumberland. -- Pertenece a la colección DL 1800-1950 del Salamanca Corpus. -- Prosa. -- John Rayson. -- H.I.H. Prince Louis-Lucien Bonaparte. -- The Song of Solomon in the Cumberland Dialect. From the Authorised English Version. -- 1858.[ES]Traducción del Cantar de los Cantares al dialecto de Cumberland.
[EN]Translation of the Song of Solomon into the dialect of Cumberland
The Song of Solomon in the Dialect of Central Cumberland
Full text linkLiteratura dialectal. -- Centro de Cumberland. -- Pertenece a la colección DL 1800-1950 del Salamanca Corpus. -- Prosa. -- William Dickinson. -- The Song of Solomon in the Dialect of Central Cumberland. -- H.I.H. Prince Louis-Lucien Bonaparte. -- 1859.[ES]Traducción del Cantar de los Cantares al dialecto del centro de Cumberland.
[EN]Translation of the Song of Solomon into the dialect of central Cumberland
- …
