75 research outputs found
Allopreening in birds is associated with parental cooperation over offspring care and stable pair bonds across years
Individuals of many species form bonds with their breeding partners, yet the mechanisms maintaining these bonds are poorly understood. In birds, allopreening is a conspicuous feature of interactions between breeding partners and has been hypothesized to play a role in strengthening and maintaining pair bonds within and across breeding attempts. Many avian species, however, do not allopreen and the relationship between allopreening and pair bonding across species remains unexplored. In a comparative analysis of allopreening and pair bond behavior, we found that allopreening between breeding partners was more common among species where parents cooperate to rear offspring. The occurrence of allopreening was also associated with an increased likelihood that partners would remain together over successive breeding seasons. However, there was no strong evidence for an association between allopreening and sexual fidelity within seasons or time spent together outside the breeding season. Allopreening between partners was also no more common in colonial or cooperatively breeding species than in solitary species. Analyses of evolutionary transitions indicated that allopreening evolved from an ancestral state of either high parental cooperation or high partner retention, and we discuss possible explanations for this. Overall, our results are consistent with an important role for allopreening in the maintenance of avian pair bonds
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Millions of historical monthly rainfall observations taken in the UK and Ireland rescued by citizen scientists
Recovering additional historical weather observations from known archival sources will improve understanding of how the climate is changing and enable detailed examination of unusual events within the historical record. The UK National Meteorological Archive recently scanned more than 66,000 paper sheets containing 5.28 million hand-written monthly rainfall observations taken across the UK and Ireland between 1677 and 1960. Only a small fraction of these observations were previously digitally available for climate scientists
to analyse. More than 16,000 volunteer citizen scientists completed the transcription of these sheets of observations during early 2020 using the RainfallRescue.org website, built using the Zooniverse platform. A total of 3.34 million observations from more than 6000 locations have so far been quality controlled and made openly available. This has increased the total number of monthly rainfall observations that are available for this time period and region by a factor of six. The newly rescued observations will enable longer and much improved reconstructions of past variations in rainfall across the British and Irish Isles, including for periods of significant flooding and drought. Specifically, this data should allow the official gridded monthly rainfall reconstructions for the UK to be extended back to 1836, and even earlier for some regions
Effect of subunit on allosteric modulation of ion channel function in stably expressed human recombinant -aminobutyric acidA receptors determined using 36Cl ion flux.
ABSTRACT Inhibitory ␥-aminobutyric acid (GABA) A receptors are subject to modulation at a variety of allosteric sites, with pharmacology dependent on receptor subunit combination. The influence of different ␣ subunits in combination with 3␥2s was examined in stably expressed human recombinant GABA A receptors by measuring 36 Cl influx through the ion channel pore. Muscimol and GABA exhibited similar maximal efficacy at each receptor subtype, although muscimol was more potent, with responses blocked by picrotoxin and bicuculline. Receptors containing the ␣3 subunit exhibited slightly lower potency. The comparative pharmacology of a range of benzodiazepine site ligands was examined, revealing a range of intrinsic efficacies at different receptor subtypes. Of the diazepam-sensitive GABA A receptors (␣1, ␣2, ␣3, ␣5), ␣5 showed the most divergence, being discriminated by zolpidem in terms of very low affinity, and CL218,872 and CGS9895 with different efficacies. Benzodiazepine potentiation at ␣33␥2s with nonselective agonist chlordiazepoxide was greater than at ␣1, ␣2, or ␣5 (P Ͻ 0.001). The presence of an ␣4 subunit conferred a unique pharmacological profile. The partial agonist bretazenil was the most efficacious benzodiazepine, despite lower ␣4 affinity, and FG8205 displayed similar efficacy. Most striking were the lack of affinity/ efficacy for classical benzodiazepines and the relatively high efficacy of Ro15-1788 (53 Ϯ 12%), CGS8216 (56 Ϯ 6%), CGS9895 (65 Ϯ 6%), and the weak partial inverse agonist Ro15-4513 (87 Ϯ 5%). Each receptor subtype was modulated by pentobarbital, loreclezole, and 5␣-pregnan-3␣-ol-20-one, but the type of ␣ subunit influenced the level of potentiation. The maximal pentobarbital response was significantly greater at ␣43␥2s (226 Ϯ 10% increase in the EC 20 response to GABA) than any other modulator. The rank order of potentiation for pregnanolone was ␣5 Ͼ ␣2 Ͼ ␣3 ϭ ␣4 Ͼ ␣1, for loreclezole ␣1 ϭ ␣2 ϭ ␣3 Ͼ ␣5 Ͼ ␣4, and for pentobarbital ␣4 ϭ ␣5 ϭ ␣2 Ͼ ␣1 ϭ ␣3
From 'event-led' to 'event-themed' regeneration: the 2002 Commonwealth Games Legacy Programme
Hosting large events has long been associated with the physical regeneration of cities. To supplement these ‘hard’ impacts, cities are now attempting to use events to stimulate ‘softer’ social and economic regeneration. This paper evaluates the impacts of a regeneration Programme adopted in conjunction with the 2002 Commonwealth Games held in Manchester, UK. Alongside its emphasis on social and economic regeneration, this Programme was unusual in that the projects were Games-themed, rather than being directly linked to the event. Despite some concerns about the organisational structures employed and the sustainability of impacts, target beneficiaries have received valuable assistance from the Programme. As such there appears to be valuable lessons that other cities can learn from this example of event regeneration
Suppression of star formation in early-type galaxies by feedback from supermassive black holes
Detailed high-resolution observations of the innermost regions of nearby
galaxies have revealed the presence of supermassive black holes1. These black
holes may interact with their host galaxies by means of 'feedback' in the form
of energy and material jets; this feedback affects the evolution of the host
and gives rise to observed relations between the black hole and the host. Here
we report observations of the ultraviolet emissions of massive early-type
galaxies. We derive an empirical relation for a critical black-hole mass (as a
function of velocity dispersion) above which the outflows from these black
holes suppress star formation in their hosts by heating and expelling all
available cold gas. Supermassive black holes are negligible in mass compared to
their hosts but nevertheless seem to play a critical role in the star formation
history of galaxies.Comment: Nature, in press. 27 pages, 4 Figures. Article & supplements with
high-resolution figures can be downloaded at:
http://www-astro.physics.ox.ac.uk/~kevins/PAPERS/AGN_feedback.pd
Stellar Kinematics and Populations of Early-Type Galaxies with the SAURON and OASIS Integral-Field Spectrographs
We summarise the results and achievements of integral-field spectroscopy of
early-type galaxies, observed as part of a survey using both the SAURON and
OASIS spectrographs. From the perspective of integral-field spectroscopy, these
otherwise smooth and featureless objects show a wealth of structure, both in
their stellar kinematics and populations. We focus on the stellar content, and
examine properties on both kiloparsec scales with SAURON, and scales of 100's
of parsecs with OASIS. These complementary studies reveal two types of
kinematically distinct components (KDCs), differing primarily in their
intrinsic sizes. In previous studies, KDCs and their host galaxies have
generally been found to be unremarkable in other aspects. We show that large
KDCs, typical of the well-studied cases, indeed show little or no age
differences with their host galaxy. The KDCs detected with the higher
spatial-resolution of OASIS are intrinsically smaller and include, in contrast,
a significant fraction of young stars. We speculate on the relationship between
KDCs and their host galaxies, and the implications for young populations in
early-type galaxies.Comment: 20 pages, 6 figures. Invited talk, submitted to "Adaptive
Optics-Assisted Integral-Field Spectroscopy", Rutten R.G.M., Benn C.R.,
Mendez J., eds., May 2005, La Palma (Spain), New Astr. Rev. For full
resolution PS, see
http://www.strw.leidenuniv.nl/~mcdermid/mcdermid_ao_workshop_20050830.ps.g
HST/NICMOS Imaging of Bright High-Redshift 24{\mu}m-selected Galaxies: Merging Properties
We present new results on the physical nature of infrared-luminous sources at
0.5<z<2.8 as revealed by HST/NICMOS imaging and IRS mid-infrared spectroscopy.
Our sample consists of 134 galaxies selected at 24\mum with a flux of S(24\mum)
> 0.9 mJy. We find many (~60%) of our sources to possess an important bulge
and/or central point source component, most of which reveal additional
underlying structures after subtraction of a best-fit sersic (or sersic+PSF)
profile. Based on visual inspection of the NIC2 images and their residuals, we
estimate that ~80% of all our sources are mergers. We calculate lower and upper
limits on the merger fraction to be 62% and 91% respectively. At z < 1.5, we
observe objects in early (pre-coalescence) merging stages to be mostly disk and
star formation dominated, while we find mergers to be mainly bulge-dominated
and AGN-starburst composites during coalescence and then AGN-dominated in late
stages. This is analogous to what is observed in local ULIRGs. At z \geq 1.5,
we find a dramatic rise in the number of objects in pre-coalescence phases of
merging, despite an increase in the preponderance of AGN signatures in their
mid-IR spectra and luminosities above 10^12.5 L_sun. We further find the
majority of mergers at those redshifts to retain a disk-dominated profile
during coalescence. We conclude that, albeit still driven by mergers, these
high-z ULIRGs are substantially different in nature from their local
counterparts and speculate that this is likely due to their higher gas content.
Finally, we observe obscured ({\tau}_{9.7\mum} > 3.36) quasars to live in faint
and compact hosts and show that these are likely high-redshift analogs of local
dense-core mergers. We find late-stage mergers to show predominantly unobscured
AGN spectra, but do not observe other morphological classes to occupy any one
specific region in the Spoon diagram. [abridged]Comment: 31 pages, 19 figures. Accepted for publication in Ap
Physical Health, Media Use, and Mental Health in Children and Adolescents With ADHD During the COVID-19 Pandemic in Australia
Objective: To examine the impact of COVID-19 restrictions among children with attention-deficit/hyperactivity disorder (ADHD). Methods: Parents of 213 Australian children (5–17 years) with ADHD completed a survey in May 2020 when COVID-19 restrictions were in place (i.e., requiring citizens to stay at home except for essential reasons). Results: Compared to pre-pandemic, children had less exercise (Odds Ratio (OR) = 0.4; 95% CI 0.3–0.6), less outdoor time (OR = 0.4; 95% 0.3–0.6), and less enjoyment in activities (OR = 6.5; 95% CI 4.0–10.4), while television (OR = 4.0; 95% CI 2.5–6.5), social media (OR = 2.4; 95% CI 1.3–4.5), gaming (OR = 2.0; 95% CI 1.3–3.0), sad/depressed mood (OR = 1.8; 95% CI 1.2–2.8), and loneliness (OR = 3.6; 95% CI 2.3–5.5) were increased. Child stress about COVID-19 restrictions was associated with poorer functioning across most domains. Most parents (64%) reported positive changes for their child including more family time. Conclusions: COVID-19 restrictions were associated with both negative and positive impacts among children with ADHD
Consortium neuroscience of attention deficit/hyperactivity disorder and autism spectrum disorder:The ENIGMA adventure
International audienc
Brain imaging of the cortex in ADHD: a coordinated analysis of large-scale clinical and population-based samples
Objective:
Neuroimaging studies show structural alterations of various brain regions in children and adults with attention deficit hyperactivity disorder (ADHD), although nonreplications are frequent. The authors sought to identify cortical characteristics related to ADHD using large-scale studies.
Methods:
Cortical thickness and surface area (based on the Desikan–Killiany atlas) were compared between case subjects with ADHD (N=2,246) and control subjects (N=1,934) for children, adolescents, and adults separately in ENIGMA-ADHD, a consortium of 36 centers. To assess familial effects on cortical measures, case subjects, unaffected siblings, and control subjects in the NeuroIMAGE study (N=506) were compared. Associations of the attention scale from the Child Behavior Checklist with cortical measures were determined in a pediatric population sample (Generation-R, N=2,707).
Results:
In the ENIGMA-ADHD sample, lower surface area values were found in children with ADHD, mainly in frontal, cingulate, and temporal regions; the largest significant effect was for total surface area (Cohen’s d=−0.21). Fusiform gyrus and temporal pole cortical thickness was also lower in children with ADHD. Neither surface area nor thickness differences were found in the adolescent or adult groups. Familial effects were seen for surface area in several regions. In an overlapping set of regions, surface area, but not thickness, was associated with attention problems in the Generation-R sample.
Conclusions:
Subtle differences in cortical surface area are widespread in children but not adolescents and adults with ADHD, confirming involvement of the frontal cortex and highlighting regions deserving further attention. Notably, the alterations behave like endophenotypes in families and are linked to ADHD symptoms in the population, extending evidence that ADHD behaves as a continuous trait in the population. Future longitudinal studies should clarify individual lifespan trajectories that lead to nonsignificant findings in adolescent and adult groups despite the presence of an ADHD diagnosis
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