2,140 research outputs found
Distinct migratory and non-migratory ecotypes of an endemic New Zealand eleotrid (Gobiomorphus cotidianus) – implications for incipient speciation in island freshwater fish species
No full textBackground: Many postglacial lakes contain fish species with distinct ecomorphs. Similar evolutionary scenarios might be acting on evolutionarily young fish communities in lakes of remote islands. One process that drives diversification in island freshwater fish species is the colonization of depauperate freshwater environments by diadromous (migratory) taxa, which secondarily lose their migratory behaviour. The loss of migration limits dispersal and gene flow between distant populations, and, therefore, is expected to facilitate local morphological and genetic differentiation. To date, most studies have focused on interspecific relationships among migratory species and their non-migratory sister taxa. We hypothesize that the loss of migration facilitates intraspecific morphological, behavioural, and genetic differentiation between migratory and non-migratory populations of facultatively diadromous taxa, and, hence, incipient speciation of island freshwater fish species.
Results: Microchemical analyses of otolith isotopes (Sr-88, Ba-137 and Ca-43) differentiated migratory and non-migratory stocks of the New Zealand endemic Gobiomorphus cotidianus McDowall (Eleotridae). Samples were taken from two rivers, one lake and two geographically-separated outgroup locations. Meristic analyses of oculoscapular lateral line canals documented a gradual reduction of these structures in the non-migratory populations. Amplified fragment length polymorphism (AFLP) fingerprints revealed considerable genetic isolation between migratory and non-migratory populations. Temporal differences in reproductive timing (migratory = winter spawners, non-migratory = summer spawners; as inferred from gonadosomatic indices) provide a prezygotic reproductive isolation mechanism between the two ecotypes.
Conclusion: This study provides a holistic look at the role of diadromy in incipient speciation of island freshwater fish species. All four analytical approaches (otolith microchemistry, morphology, spawning timing, population genetics) yield congruent results, and provide clear and independent evidence for the existence of distinct migratory and non-migratory ecotypes within a river in a geographically confined range. The morphological changes within the non-migratory populations parallel interspecific patterns observed in all non-migratory New Zealand endemic Gobiomorphus species and other derived gobiid taxa, a pattern suggesting parallel evolution. This study indicates, for the first time, that distinct ecotypes of island freshwater fish species may be formed as a consequence of loss of migration and subsequent diversification. Therefore, if reproductive isolation persists, these processes may provide a mechanism to facilitate speciation
State-Space Inference and Learning with Gaussian Processes
No full text18.10.13 KB. Ok to add author version to spiral, authors hold copyright.State-space inference and learning with Gaussian processes (GPs) is an unsolved problem. We propose a new, general methodology for inference and learning in nonlinear state-space models that are described probabilistically by non-parametric GP models. We apply the expectation maximization algorithm to iterate between inference in the latent state-space and learning the parameters of the underlying GP dynamics model. Copyright 2010 by the authors
Silence in Modern Literature and Philosophy: Beckett, Barthes, Nancy, Stevens
No full textThis book discusses the elusive centrality of silence in modern literature and philosophy, focusing on the writing and theory of Jean-Luc Nancy and Roland Barthes, the prose of Samuel Beckett, and the poetry of Wallace Stevens. It suggests that silence is best understood according to two categories: apophasis and reticence. Apophasis is associated with theology, and relates to a silence of ineffability and transcendence; reticence is associated with phenomenology, and relates to a silence of listenership and speechlessness. In a series of diverse though interrelated readings, the study examines figures of broken silence and silent voice in the prose of Samuel Beckett, the notion of shared silence in Jean-Luc Nancy and Roland Barthes, and ways in which the poetry of Wallace Stevens mounts lyrical negotiations with forms of unsayability and speechlessness
Advance care planning in general practice and beyond : a cluster-randomized controlled trial of the ACP-GP intervention
No full textPeople with a chronic, life-limiting illness may be confronted with complex choices about their medical care. Their illness may also lead to a loss of decisional capacity. Advance care planning (ACP) is a process of communication between the patient, healthcare professionals, and loved ones, about the patient’s values, wishes, and goals for care. By discussing these topics in a timely manner and revisiting them over time, all involved parties can be better prepared for medical decision-making in the moment and in the future. Outpatient settings, such as general practice and primary care, have been proposed as ideal for initiating and facilitating ACP. However, deficits remain in ACP in this setting, including in Belgian general practice. To mitigate barriers and maximize facilitators to ACP in Belgian general practice, a complex intervention, the ACP-GP intervention, has been developed. In the first part of this dissertation, the intervention is implemented and evaluated through a cluster-randomized controlled trial with a parallel process evaluation. The second part of this dissertation complements the first by describing insights into the implementation of ACP interventions internationally. This is accomplished through a scoping review of the literature and a qualitative study of clinicians’ experiences implementing an ACP pathway in two Canadian provinces. The findings from this dissertation lead to several recommendations for practice, policy, and future research directions.
Julie Stevens has a background in Clinical Psychology. She is a researcher at the End-of-Life Care Research Group (Vrije Universiteit Brussel – Ghent University)
Systematic Reconstruction of Molecular Cascades Regulating GP Development Using Single-Cell RNA-Seq
No full textSummaryThe growth plate (GP) comprising sequentially differentiated cell layers is a critical structure for bone elongation and regeneration. Although several key regulators in GP development have been identified using genetic perturbation, systematic understanding is still limited. Here, we used single-cell RNA-sequencing (RNA-seq) to determine the gene expression profiles of 217 single cells from GPs and developed a bioinformatics pipeline named Sinova to de novo reconstruct physiological GP development in both temporal and spatial high resolution. Our unsupervised model not only confirmed prior knowledge, but also enabled the systematic discovery of genes, potential signal pathways, and surface markers CD9/CD200 to precisely depict development. Sinova further identified the effective combination of transcriptional factors (TFs) that regulates GP maturation, and the result was validated using an in vitro EGFP-Col10a screening system. Our case systematically reconstructed molecular cascades in GP development through single-cell profiling, and the bioinformatics pipeline is applicable to other developmental processes.Video Abstrac
A survey assessment of reporting radiographers' scope of practice in the West Midlands region of the United Kingdom
No full textIntroduction: Radiographers have been providing reporting solutions for a number of years. Given the persistent radiologist vacancies and the increased demand on imaging services, the utilisation of reporting radiographers is widespread across England. Capacity and demand issues may lead to reporting boundaries being extended. The aim was to generate an updated appraisal of participants' scopes of practice in the West Midlands of region of England. Method: Reporting radiographers at 11 healthcare institutions across the West Midlands region were invited to participate in an online survey. Topics covered included reporting scope of practice, onward referrals and suggestion of treatments. Descriptive statistics were generated in Microsoft Excel and free responses were analysed manually. Results: Response rate was 47% (40/86). The majority (n ¼ 34, 85%) report Emergency Department skeletal examinations, only 12 (30%) report adult chests and only three (8%) report paediatric chests. Of those permitted to refer to other modalities, 85% (n ¼ 23/27) actively do so. Of those permitted to refer to specialist teams, 97% (n ¼ 31/32) actively do so. Only 23% of all participants (n ¼ 9/40) suggest treatments in their reports. Conclusion: An increased number of participants report chest and abdominal examinations than previously identified. Restrictions in paediatric scopes of practice and adult GP chest examinations are also evident. Participants stated they do include recommendations in their reports by referring to other modalities and for specialist opinions. Suggesting treatment is not common practice and is considered an area for further advancement. Crow
Performances of authorial presence and absence : the author dies hard
No full textThis book takes Roland Barthes’s famous proclamation of ‘The Death of the Author’ as a starting point to investigate concepts of authorial presence and absence on various levels of text and performance. By offering a new understanding of ‘the author’ as neither a source of unquestioned authority nor an obsolete construct, but rather as a performative figure, the book illuminates wide-ranging aesthetic and political aspects of ‘authorial death’ by asking: how is the author constructed through cultural and political imaginaries and erasures, intertextual and intertheatrical references, re-performances and self-referentiality? And what are the politics and ethics of these constructions
Vliv Moto GP na cestovní ruch v Brně
No full textThe main aim of the bachelor thesis is find out how Moto GP influence tourism in Brno, what is the availability of accommodation facilities, what is the increase in prices during this period. In the theoretical part, analyse the tourism as a whole, destination of tourism, Moto GP. Practical part examines using a questionnaire how residents perceive the action Moto GP. There is unfortunately not sufficient statistical data to determine the icrease in prices as well as occupancy of acommodation capacities in the period when Moto GP race takes place in Brno. That is the reason why the author of this thesis has decided to conduct a research by using a sample of 10 % of hotels in Brno to be able to answer these questions
Region 2 of the Escherichia coli K5 gene cluster encoding proteins for the biosynthesis of the K5 polysaccharide
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