1,395 research outputs found
Editorial: Post-anesthesia Cognitive Dysfunction: How, When and Why
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
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
Development and automation of a test of impulse control in zebrafish.
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
Moderate early life stress improves adult zebrafish (Danio rerio) working memory but does not affect social and anxiety-like responses
Dirac-harmonic maps from index theory
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
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
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
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
Assessment of a novel, capsid-modified adenovirus with an improved vascular gene transfer profile
<p>Background: Cardiovascular disorders, including coronary artery bypass graft failure and in-stent restenosis remain significant opportunities for the advancement of novel therapeutics that target neointimal hyperplasia, a characteristic of both pathologies. Gene therapy may provide a successful approach to improve the clinical outcome of these conditions, but would benefit from the development of more efficient vectors for vascular gene delivery. The aim of this study was to assess whether a novel genetically engineered Adenovirus could be utilised to produce enhanced levels of vascular gene expression.</p>
<p>Methods: Vascular transduction capacity was assessed in primary human saphenous vein smooth muscle and endothelial cells using vectors expressing the LacZ reporter gene. The therapeutic capacity of the vectors was compared by measuring smooth muscle cell metabolic activity and migration following infection with vectors that over-express the candidate therapeutic gene tissue inhibitor of matrix metalloproteinase-3 (TIMP-3).</p>
<p>Results: Compared to Adenovirus serotype 5 (Ad5), the novel vector Ad5T*F35++ demonstrated improved binding and transduction of human vascular cells. Ad5T*F35++ mediated expression of TIMP-3 reduced smooth muscle cell metabolic activity and migration in vitro. We also demonstrated that in human serum samples pre-existing neutralising antibodies to Ad5T*F35++ were less prevalent than Ad5 neutralising antibodies.</p>
<p>Conclusions: We have developed a novel vector with improved vascular transduction and improved resistance to human serum neutralisation. This may provide a novel vector platform for human vascular gene transfer.</p>
Modeling the total and polarized emission in evolving galaxies: "spotty" magnetic structures
Future radio observations with the SKA and its precursors will be sensitive
to trace spiral galaxies and their magnetic field configurations up to redshift
. We suggest an evolutionary model for the magnetic configuration in
star-forming disk galaxies and simulate the magnetic field distribution, the
total and polarized synchrotron emission, and the Faraday rotation measures for
disk galaxies at z\la 3. Since details of dynamo action in young galaxies are
quite uncertain, we model the dynamo action heuristically relying only on
well-established ideas of the form and evolution of magnetic fields produced by
the mean-field dynamo in a thin disk. We assume a small-scale seed field which
is then amplified by the small-scale turbulent dynamo up to energy
equipartition with kinetic energy of turbulence. The large-scale galactic
dynamo starts from seed fields of 100 pc and an averaged regular field strength
of 0.02\,G, which then evolves to a "spotty" magnetic field configuration
in about 0.8\,Gyr with scales of about one kpc and an averaged regular field
strength of 0.6\,G. The evolution of these magnetic spots is simulated
under the influence of star formation, dynamo action, stretching by
differential rotation of the disk, and turbulent diffusion. The evolution of
the regular magnetic field in a disk of a spiral galaxy, as well as the
expected total intensity, linear polarization and Faraday rotation are
simulated in the rest frame of a galaxy at 5\,GHz and 150\,MHz and in the rest
frame of the observer at 150\,MHz. We present the corresponding maps for
several epochs after disk formation. (abridged)Comment: 13 pages, 6 figures, 2 tables, revised version is accepted for
publication in Astronomische Nachrichte
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