174 research outputs found

    European shag diet and demography at a North Sea colony over half a century of environmental change

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    The earth’s climate is changing rapidly, with pronounced impacts observed in all well studied ecosystems throughout the globe. Climate-mediated impacts are particularly marked and rapid within marine ecosystems. At the apex of such systems, marine top predators, such as seabirds, are vulnerable to direct and indirect climate-mediated effects, which may alter foraging capacity and prey availability. Consequently, many seabird populations are displaying pronounced changes in diet composition and declining demographic trends, yet the mechanisms underpinning these responses remain largely untested. Although many studies have quantified seabird diet during the breeding season, the climate-related mechanisms determining long-term trends in diet composition are less well understood. Further, as the majority of seabird mortality occurs during winter, the diet of seabirds in winter is a key knowledge gap. Demographic trends have also been observed in numerous seabird species but, as with diet, we have limited understanding of the key mechanisms whereby climate is driving these trends. Finally, analyses of climate have focussed on broad scale processes, yet variation in microclimate may also be a key determinant of fine-scale distribution and demography within seabird colonies, yet this potential factor has been overlooked. As a long-lived species with highly variable demography and plastic foraging habits, the European shag Phalacrocorax aristotelis provides an ideal species to investigate the impacts of environmental change on marine top-predator demography. This thesis uses demographic and diet datasets collected from a shag population breeding on the Isle of May, southeast Scotland, over half a century. By combining these data with environmental covariates, collected over a range of temporal and spatial scales, I quantify the response of this population to pronounced environmental change within the North Sea over the last five decades. My thesis reveals that the diet of nestling shags in this population has changed dramatically over this period, from an almost complete dependence on lesser sandeel Ammodytes marinus to a range of prey types. Crucially, a suite of environmental covariates, including daily wind and long-term ocean warming, has contributed to this change in diet. The diet in winter displayed similar temporal trends (reduced sandeel and greater diversity). However, I found that the reduction in sandeel occurrence was more marked during the non-breeding period, with potential demographic consequences. I also documented a substantial increase in productivity and rapid phenological advancement over the last half a century. Crucially, the productivity trend was linked to this advancing phenology, which in turn was determined by conditions experienced in late winter and in the previous breeding season. Finally, pronounced fine-scale distributional trends occurred in this colony, with an increasing proportion of individuals breeding on the north-east side of the island, showing more rapid improvements in reproductive output than the declining sub-colonies in the south-west. This redistribution may benefit the population since exposure is a key factor in productivity and the prevailing wind direction is westerly. Overall, these results suggest that substantial dietary and demographic plasticity in shags may confer some resilience in this species to predicted future climate-mediated environmental change

    Reprint: Good laboratory practice: preventing introduction of bias at the bench

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    As a research community, we have failed to show that drugs, which show substantial efficacy in animal models of cerebral ischemia, can also improve outcome in human stroke. Accumulating evidence suggests this may be due, at least in part, to problems in the design, conduct, and reporting of animal experiments which create a systematic bias resulting in the overstatement of neuroprotective efficacy. Here, we set out a series of measures to reduce bias in the design, conduct and reporting of animal experiments modeling human stroke

    Pronounced long-term trends in year-round diet composition of the European shag Phalacrocorax aristotelis

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    © 2018, Springer-Verlag GmbH Germany, part of Springer Nature. Populations of marine top predators are exhibiting pronounced demographic changes due to alterations in prey availability and quality. Changes in diet composition is a key potential mechanism whereby alterations in prey availability can affect predator demography. Studies of long-term trends in diet have focused on the breeding season. However, long-term changes in non-breeding season diet is an important knowledge gap, since this is generally the most critical period of the year for the demography of marine top predators. In this study, we analysed 495,239 otoliths from 5888 regurgitated pellets collected throughout the annual cycle over three decades (1985–2014) from European shags Phalacrocorax aristotelis on the Isle of May, Scotland (56°11′N, 02°33′W). We identified dramatic reductions in the frequency of lesser sandeel Ammodytes marinus occurrence over the study, which was more pronounced during the non-breeding period (96% in 1988 to 45% in 2014), than the breeding period (91–67%). The relative numerical abundance of sandeel per pellet also reduced markedly (100–13% of all otoliths), with similar trends apparent during breeding and non-breeding periods. In contrast, the frequencies of Gadidae, Cottidae, Pleuronectidae and Gobiidae all increased, resulting in a doubling in annual prey richness from 6 prey types per year in 1988 to 12 in 2014. Our study demonstrates that the declining importance of the previously most prominent prey and marked increase in diet diversity is apparent throughout the annual cycle, suggesting that substantial temporal changes in prey populations have occurred, which may have important implications for seabird population dynamics

    Curriculum factors influencing knowledge of communication skills among medical students

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    Background Communication training builds on the assumption that understanding of the concepts related to professional communication facilitates the training. We know little about whether students' knowledge of clinical communication skills is affected by their attendance of communication training courses, or to what degree other elements of the clinical training or curriculum design also play a role. The aim of this study was to determine which elements of the curriculum influence acquisition of knowledge regarding clinical communication skills by medical students. Methods The study design was a cross-sectional survey performed in the four Norwegian medical schools with different curricula, spring 2003. A self-administered questionnaire regarding knowledge of communication skills (an abridged version of van Dalen's paper-and-pencil test) was sent to all students attending the four medical schools. A total of 1801 (59%) students responded with complete questionnaires. Results At the end of the 1st year of study, the score on the knowledge test was higher in students at the two schools running communication courses and providing early patient contact (mean 81%) than in the other two medical schools (mean 69–75%, P ≤ 0.001), with students studying a traditional curriculum scoring the lowest. Their scores increased sharply towards the end of the 3rd year, during which they had been subjected to extensive patient contact and had participated in an intensive communication course (77% vs. 72% the previous year, P ≤ 0.01). All students scored generally lower in academic years in which there was no communication training. However, at the end of the final year the difference between the schools was only 5% (81% vs. 86%, P ≤ 0.001). Conclusion The acquisition of knowledge regarding communication skills by medical students may be optimised when the training is given together with extensive supervised patient contact, especially if this teaching takes place in the initial years of the curriculum

    Breast imaging technology: Imaging biochemistry - applications to breast cancer

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    The use of magnetic resonance spectroscopy (MRS) to investigate breast tumour biochemistry in vivo is reviewed. To this end, results obtained both from patients in vivo and from tumour extracts and model systems are discussed. An association has been observed between transformation and an increase in phosphomonoesters (PMEs) detected in the (31)P MRS spectrum, as well as an increase in choline-containing metabolites detected in the (1)H spectrum. A decrease in PME content after treatment is associated with response to treatment as assessed by tumour volume. Experiments in model systems aimed at understanding the underlying biochemical processes are presented, as well as data indicating the usefulness of MRS in monitoring the uptake and metabolism of some chemotherapeutic agents

    Meta-analysis of variation suggests that embracing variability improves both replicability and generalizability in preclinical research

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    The replicability of research results has been a cause of increasing concern to the scientific community. The long-held belief that experimental standardization begets replicability has also been recently challenged, with the observation that the reduction of variability within studies can lead to idiosyncratic, lab-specific results that cannot be replicated. An alternative approach is to, instead, deliberately introduce heterogeneity, known as "heterogenization" of experimental design. Here, we explore a novel perspective in the heterogenization program in a meta-analysis of variability in observed phenotypic outcomes in both control and experimental animal models of ischemic stroke. First, by quantifying interindividual variability across control groups, we illustrate that the amount of heterogeneity in disease state (infarct volume) differs according to methodological approach, for example, in disease induction methods and disease models. We argue that such methods may improve replicability by creating diverse and representative distribution of baseline disease state in the reference group, against which treatment efficacy is assessed. Second, we illustrate how meta-analysis can be used to simultaneously assess efficacy and stability (i.e., mean effect and among-individual variability). We identify treatments that have efficacy and are generalizable to the population level (i.e., low interindividual variability), as well as those where there is high interindividual variability in response; for these, latter treatments translation to a clinical setting may require nuance. We argue that by embracing rather than seeking to minimize variability in phenotypic outcomes, we can motivate the shift toward heterogenization and improve both the replicability and generalizability of preclinical research

    Adaptation of a Mindfulness-Based Intervention for Incarcerated Young Men: a Feasibility Study

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    Objectives: Incarcerated young men commonly experience problems with impulsivity and emotional dysregulation. Mindfulness training could help but the evidence is limited. This study developed and piloted an adapted mindfulness-based intervention for this group (n = 48). Methods: Feasibility of recruitment, retention, and data collection were assessed, and the effectiveness of mindfulness training measured using validated questionnaires. Twenty-five qualitative interviews were conducted to explore experiences of the course, and barriers and facilitators to taking part. Results: The findings indicated that recruitment and retention to mindfulness training groups was a challenge despite trying various adaptive strategies to improve interest, relevance, and acceptability. Quantitative data collection was feasible at baseline and post-course. There were significant improvements following training in impulsivity (effect size [ES] 0.72, 95% CI 0.32–1.11, p = 0.001), mental wellbeing (ES 0.50; 95% CI 0.18–0.80; p = 0.003), inner resilience (comprehensibility ES 0.35; 95% CI − 0.02–0.68; p = 0.03), and mindfulness (ES 0.32; 95% CI 0.03–0.60; p = 0.03). The majority (70%) of participants reported finding the course uncomfortable or disconcerting at first but if they chose to remain, this changed as they began to experience benefit. The body scan and breathing techniques were reported as being most helpful. Positive experiences included better sleep, less stress, feeling more in control, and improved relationships. Conclusions: Developing and delivering mindfulness training for incarcerated young men is feasible and may be beneficial, but recruitment and retention may limit reach. Further studies are required that include a control group

    Mindfulness based cognitive therapy improves frontal control in bipolar disorder: a pilot EEG study

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    <p>Abstract</p> <p>Background</p> <p>Cognitive processing in Bipolar Disorder is characterized by a number of attentional abnormalities. Mindfulness Based Cognitive Therapy combines mindfulness meditation, a form of attentional training, along with aspects of cognitive therapy, and may improve attentional dysfunction in bipolar disorder patients.</p> <p>Methods</p> <p>12 euthymic BD patients and 9 control participants underwent record of electroencephalography (EEG, band frequency analysis) during resting states (eyes open, eyes closed) and during the completion of a continuous performance task (A-X version, EEG event-related potential (ERP) wave component analysis). The individuals with BD completed an 8-week MBCT intervention and record of EEG was repeated.</p> <p>Results</p> <p>(1) Brain activity, individuals with BD showed significantly decreased theta band power, increased beta band power, and decreased theta/beta ratios during the resting state, eyes closed, for frontal and cingulate cortices. Post MBCT intervention improvement over the right frontal cortex was seen in the individuals with BD, as beta band power decreased. (2) Brain activation, individuals with BD showed a significant P300-like wave form over the frontal cortex during the cue. Post MBCT intervention the P300-like waveform was significantly attenuated over the frontal cortex.</p> <p>Conclusions</p> <p>Individuals with BD show decreased attentional readiness and activation of non-relevant information processing during attentional processes. These data are the first that show, MBCT in BD improved attentional readiness, and attenuated activation of non-relevant information processing during attentional processes.</p

    Small-Bodied Humans from Palau, Micronesia

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    UNLABELLED: Newly discovered fossil assemblages of small bodied Homo sapiens from Palau, Micronesia possess characters thought to be taxonomically primitive for the genus Homo. BACKGROUND: Recent surface collection and test excavation in limestone caves in the rock islands of Palau, Micronesia, has produced a sizeable sample of human skeletal remains dating roughly between 940-2890 cal ybp. PRINCIPLE FINDINGS: Preliminary analysis indicates that this material is important for two reasons. First, individuals from the older time horizons are small in body size even relative to "pygmoid" populations from Southeast Asia and Indonesia, and thus may represent a marked case of human insular dwarfism. Second, while possessing a number of derived features that align them with Homo sapiens, the human remains from Palau also exhibit several skeletal traits that are considered to be primitive for the genus Homo. SIGNIFICANCE: These features may be previously unrecognized developmental correlates of small body size and, if so, they may have important implications for interpreting the taxonomic affinities of fossil specimens of Homo
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