1,615 research outputs found

    Social effects of territorial neighbours on the timing of spring breeding in North American red squirrels

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    This is the author accepted manuscript. The final version is available from Wiley via the DOI in this recordOrganisms can affect one another’s phenotypes when they socially interact. Indirect genetic effects occur when an individual’s phenotype is affected by genes expressed in another individual. These heritable effects can enhance or reduce adaptive potential, thereby accelerating or reversing evolutionary change. Quantifying these social effects is therefore crucial for our understanding of evolution, yet estimates of indirect genetic effects in wild animals are limited to dyadic interactions. We estimated indirect phenotypic and genetic effects, and their covariance with direct effects, for the date of spring breeding in North American red squirrels (Tamiasciurus hudsonicus) living in an array of territories of varying spatial proximity. Additionally, we estimated indirect effects and the strength of selection at low and high population densities. Social effects of neighbours on the date of spring breeding were different from zero at high population densities but not at low population densities. Indirect phenotypic effects accounted for a larger amount of variation in the date of breeding than differences attributable to the among-individual variance, suggesting social interactions are important for determining breeding dates. The genetic component to these indirect effects was however not statistically significant. We therefore showcase a powerful and flexible method that will allow researchers working in organisms with a range of social systems to estimate indirect phenotypic and genetic effects, and demonstrate the degree to which social interactions can influence phenotypes, even in a solitary species

    18F-GE-180: a novel TSPO radiotracer compared to 11C-R-PK11195 in a preclinical model of stroke

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    PURPOSE: Neuroinflammation plays a critical role in various neuropathological conditions, and hence there is renewed interest in the translocator protein (TSPO) as a biomarker of microglial activation and macrophage infiltration in the brain. This is reflected in the large amount of research conducted seeking to replace the prototypical PET radiotracer 11C-R-PK11195 with a TSPO ligand with higher performance. Here we report the in vivo preclinical investigation of the novel TSPO tracer 18F-GE-180 in a rat model of stroke. METHODS: Focal cerebral ischaemia was induced in Wistar rats by 60-min occlusion of the middle cerebral artery (MCAO). Brain damage was assessed 24 h after MCAO by T2 MRI. Rats were scanned with 11C-R-PK11195 and 18F-GE-180 5 or 6 days after MCAO. Specificity of binding was confirmed by injection of unlabelled R-PK11195 or GE-180 20 min after injection of 18F-GE-180. In vivo data were confirmed by ex vivo immunohistochemistry for microglial (CD11b) and astrocytic biomarkers (GFAP). RESULTS: 18F-GE-180 uptake was 24 % higher in the core of the ischaemic lesion and 18 % lower in the contralateral healthy tissue than that of 11C-R-PK11195 uptake (1.5 ± 0.2-fold higher signal to noise ratio). We confirmed this finding using the simplified reference tissue model (BPND = 3.5 ± 0.4 and 2.4 ± 0.5 for 18F-GE-180 and 11C-R-PK11195, respectively, with R 1 = 1). Injection of unlabelled R-PK11195 or GE-180 20 min after injection of 18F-GE-180 significantly displaced 18F-GE-180 (69 ± 5 % and 63 ± 4 %, respectively). Specificity of the binding was also confirmed by in vitro autoradiography, and the location and presence of activated microglia and infiltrated macrophages were confirmed by immunohistochemistry. CONCLUSION: The in vivo binding characteristics of 18F-GE-180 demonstrate a better signal to noise ratio than 11C-R-PK11195 due to both a better signal in the lesion and lower nonspecific binding in healthy tissue. These results provide evidence that 18F-GE-180 is a strong candidate to replace 11C-R-PK11195

    The play's the thing

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    For very understandable reasons phenomenological approaches predominate in the field of sensory urbanism. This paper does not seek to add to that particular discourse. Rather it takes Rorty’s postmodernized Pragmatism as its starting point and develops a position on the role of multi-modal design representation in the design process as a means of admitting many voices and managing multidisciplinary collaboration. This paper will interrogate some of the concepts underpinning the Sensory Urbanism project to help define the scope of interest in multi-modal representations. It will then explore a range of techniques and approaches developed by artists and designers during the past fifty years or so and comment on how they might inform the question of multi-modal representation. In conclusion I will argue that we should develop a heterogeneous tool kit that adopts, adapts and re-invents existing methods because this will better serve our purposes during the exploratory phase(s) of any design project that deals with complexity

    Laboratory and field measurements of nail guns' noise emission

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    Field measurements and laboratory measurements using EN 12549 was presented. The rig was held in a small comfortable backpack and even if the sensors were wired to the acquisition card, the worker could work without obstruction. Between 8 and 12 trials of 10 impacts were recorded for each nailer/worker combination. Eight framing nailers and two roofing nailers were tested in the laboratory under controlled conditions as per the EN 12549 standard. From this standard, three operators were required to perform five trials of 10 nails each, with each trial lasting a period of 30 seconds. The measures were performed in a semi anechoic room where both the sound power and the sound pressure level at the worker?s ear were measured. Concerning the EN 12549 standard, it seems appropriate in order to perform representative workplace ranking of nailers following their sound power level values. Concerning the reduction of workers? noise exposure, the battery operated nailer stands out as the best choice as its level is at least 6 dBs lower than any other tested nailer in both lab and field measurements

    Optimisation of energetic and reproductive gains explains behavioural responses to environmental variation across seasons and years

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    Animals switch between inactive and active states, simultaneously impacting their energy intake, energy expenditure and predation risk, and collectively defining how they engage with environmental variation and trophic interactions. We assess daily activity responses to long‐term variation in temperature, resources and mating opportunities to examine whether individuals choose to be active or inactive according to an optimisation of the relative energetic and reproductive gains each state offers. We show that this simplified behavioural decision approach predicts most activity variation (R2 = 0.83) expressed by free‐ranging red squirrels over 4 years, as quantified through accelerometer recordings (489 deployments; 5066 squirrel‐days). Recognising activity as a determinant of energetic status, the predictability of activity variation aggregated at a daily scale, and the clear signal that behaviour is environmentally forced through optimisation of gain, provides an integrated approach to examine behavioural variation as an intermediary between environmental variation and energetic, life‐history and ecological outcomes.By assessing daily activity responses to long‐term variation in temperature, resources, and mating opportunities, we examine whether individuals choose to be active or inactive according to an optimization of energetic and reproductive gains. This simplified behavioural decision approach predicts most daily activity variation (R2 = 0.83) expressed by free‐ranging red squirrels over four years, as quantified through accelerometer recordings. Here we provide an integrated approach to examine behavioural variation as an intermediary between environmental variation and energetic, life‐history, and ecological outcomes.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154889/1/ele13494_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154889/2/ele13494.pd

    Optical studies for the super separator spectrometer S3

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    International audienceS3 (Super Separator Spectrometer) [1] is a future device designed for experiments with the high intensity heavy ion stable beams of SPIRAL2 [2] at GANIL (Caen, France). It will include a target resistant to these very high intensities, a first stage momentum achromat for primary beam extraction and suppression, a second stage mass spectrometer and a dedicated detection system. This spectrometer includes large aperture quadrupole triplets with embedded multipolar corrections. To enable the primary beam extraction one triplet has to be opened on one side, which requires an appropriate design of such a multipolar magnet. The final mass separation power required for S3 needs a careful design of the optics with a high level of aberration correction. Multiple symmetric lattices were studied for this purpose. A 4-fold symmetric lattice and the achieved results are described in this paper

    Direct observation of long-lived isomers in 212^{212}Bi

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    Long-lived isomers in 212Bi have been studied following 238U projectile fragmentation at 670 MeV per nucleon. The fragmentation products were injected as highly charged ions into the GSI storage ring, giving access to masses and half-lives. While the excitation energy of the first isomer of 212Bi was confirmed, the second isomer was observed at 1478(30) keV, in contrast to the previously accepted value of >1910 keV. It was also found to have an extended Lorentz-corrected in-ring halflife >30 min, compared to 7.0(3) min for the neutral atom. Both the energy and half-life differences can be understood as being due a substantial, though previously unrecognised, internal decay branch for neutral atoms. Earlier shell-model calculations are now found to give good agreement with the isomer excitation energy. Furthermore, these and new calculations predict the existence of states at slightly higher energy that could facilitate isomer de-excitation studies.Comment: published in PRL 110, 12250

    Environmental Asbestotic Pleural Plaques in Northeast Corsica: Correlations with Airborne and Pleural Mineralogic Analysis

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    We report a prevalence study of environmental pleural plaques in subjects over 50 years old from the northeastern Corsican village of Murato, built on asbestos surface deposits. The percentage of plaques was 41%, versus 7.5% in the control village of Vezzani. Although surface deposits contain both chrysotile and tremolite, airborne pollution and asbestos lung burden of exposed inhabitants consist essentially of tremolite as assessed by transmission electron microscopy (TEM). However, TEM analysis of the parietal pleura of three animals bred in exposed areas showed a predominance of short fibers of chrysotile. The respective roles of tremolite and chrysotile in inducing pleural plaques in Corsica should thus be considered.—Environ Health Perspect 102(Suppl 5):251–252 (1994
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