1,796 research outputs found

    Editorial: Post-anesthesia Cognitive Dysfunction: How, When and Why

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    This work has been funded by FEDER funds through COMPETE 2020 and the POCI (POCI-01-0145-FEDER-029542), Portugal 2020, and by Fundação para a Ciência e a Tecnologia under the project PTDC/CVT-CVT/29542/2017

    The role of zebrafish (Danio rerio) in dissecting the genetics and neural circuits of executive function

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    Zebrafish have great potential to contribute to our understanding of behavioural genetics and thus to contribute to our understanding of the aetiology of psychiatric disease. However, progress is dependent upon the rate at which behavioural assays addressing complex behavioural phenotypes are designed, reported and validated. Here we critically review existing behavioural assays with particular focus on the use of adult zebrafish to explore executive processes and phenotypes associated with human psychiatric disease. We outline the case for using zebrafish as models to study impulse control and attention, discussing the validity of applying extant rodent assays to zebrafish and evidence for the conservation of relevant neural circuits

    Sustained Effects of Developmental Exposure to Ethanol on Zebrafish Anxiety-Like Behaviour

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    <p>Stress-related behaviour assessed by thigmotaxis in zebrafish larvae A,B) 9dpf, C,D) 10dpf, E,F) 23dpf juveniles. G,H) Effect of diazepam on larval stress-reactivity assessed by thigmotaxis. Time course of average time spent each minute at the edge of the apparatus (A, C, E), overall average time spent per minute at the edge of the apparatus (B, D, F). (A-D) Developmental ethanol exposure decreased thigmotaxis at both 9dpf (A,B: <i>F</i> 2,105 = 4.76, <i>P</i><0.05) and 10dpf (C,D: <i>F</i> 2, 285 = 6.69, <i>P</i><0.05), with the greatest difference between 20mM ethanol treatment and the control. Siblings of the same animals were raised for another 2 weeks and tested as 23 dpf juveniles (E,F). These juveniles exhibited a similar thigmotaxis response as at 9dpf, with decreased thigmotaxis in ethanol treated animals compared to controls (<i>F</i> 2,146 = 2.93, <i>P</i><0.05). (G-H) Larvae acutely treated with diazepam for 6 minutes exhibited significantly reduced time spent at the edges of the wells compared to controls (<i>F</i> 1, 259 = 5.47, <i>P</i><0.01). There were no significant differences in distance travelled. Post-hoc t-test: *** <i>P</i><0.001, ** <i>P</i><0.01.</p

    Development and automation of a test of impulse control in zebrafish.

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    Deficits in impulse control (difficulties in inhibition of a pre-potent response) are fundamental to a number of psychiatric disorders, but the molecular and cellular basis is poorly understood. Zebrafish offer a very useful model for exploring these mechanisms, but there is currently a lack of validated procedures for measuring impulsivity in fish. In mammals, impulsivity can be measured by examining rates of anticipatory responding in the 5-choice serial reaction time task (5-CSRTT), a continuous performance task where the subject is reinforced upon accurate detection of a briefly presented light in one of five distinct spatial locations. This paper describes the development of a fully-integrated automated system for testing impulsivity in adult zebrafish. We outline the development of our image analysis software and its integration with National Instruments drivers and actuators to produce the system. We also describe an initial validation of the system through a one-generation screen of chemically mutagenized zebrafish, where the testing parameters were optimized

    Dirac-harmonic maps from index theory

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    We prove existence results for Dirac-harmonic maps using index theoretical tools. They are mainly interesting if the source manifold has dimension 1 or 2 modulo 8. Our solutions are uncoupled in the sense that the underlying map between the source and target manifolds is a harmonic map.Comment: 26 pages, no figur

    The orthodontic-oral surgery interface. Part two: diagnosis and management of anomalies in eruption and transpositions

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    The orthodontic-oral surgery interface is important for the multidisciplinary management of patients presenting with complex dental anomalies. This article provides an overview of anomalies of eruption and transpositions, their diagnosis, aetiology, presenting features and the different management options. It also highlights the role of the general dental practitioner (GDP) in identifying such anomalies and the importance of timely referral to specialist care

    Why Do Stars Form In Clusters? An Analytic Model for Stellar Correlation Functions

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    Recently, we have shown that if the ISM is governed by super-sonic turbulent flows, the excursion-set formalism can be used to calculate the statistics of self-gravitating objects over a wide range of scales. On the largest self-gravitating scales ('first crossing'), these correspond to GMCs, and on the smallest non-fragmenting self-gravitating scales ('last crossing'), to protostellar cores. Here, we extend this formalism to rigorously calculate the auto and cross-correlation functions of cores (and by extension, young stars) as a function of spatial separation and mass, in analogy to the cosmological calculation of halo clustering. We show that this generically predicts that star formation is very strongly clustered on small scales: stars form in clusters, themselves inside GMCs. Outside the binary-star regime, the projected correlation function declines as a weak power-law, until a characteristic scale which corresponds to the characteristic mass scale of GMCs. On much larger scales the clustering declines such that star formation is not strongly biased on galactic scales, relative to the actual dense gas distribution. The precise correlation function shape depends on properties of the turbulent spectrum, but its qualitative behavior is quite general. The predictions agree well with observations of young star and core autocorrelation functions over ~4 dex in radius. Clustered star formation is a generic consequence of supersonic turbulence if most of the power in the velocity field, hence the contribution to density fluctuations, comes from large scales. The distribution of self-gravitating masses near the sonic length is then imprinted by fluctuations on larger scales. We similarly show that the fraction of stars formed in 'isolated' modes should be small (\lesssim10%).Comment: 8 pages, 3 figures, accepted to MNRAS (minor revisions to match accepted version

    Role of Active Contraction and Tropomodulins in Regulating Actin Filament Length and Sarcomere Structure in Developing Zebrafish Skeletal Muscle

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    LM was supported by a studentship from Queen Mary, University of London. Work in collaboration with Professor Arner and Dr. Li supported by The Physiological Society and EuFishBioMed. Research at KI was supported by the Swedish Research Council (2013–3003) and French Muscular Dystrophy Association (AFM
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