878 research outputs found

    Early sensitivity for eyes within faces: A new neuronal account of holistic and featural processing

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    The final publication is available at Elsevier via http://dx.doi.org/10.1016/j.neuroimage.2014.04.042. © 2014. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Eyes are central to face processing however their role in early face encoding as reflected by the N170 ERP component is unclear. Using eye tracking to enforce fixation on specific facial features, we found that the N170 was larger for fixation on the eyes compared to fixation on the forehead, nasion, nose or mouth, which all yielded similar amplitudes. This eye sensitivity was seen in both upright and inverted faces and was lost in eyeless faces, demonstrating it was due to the presence of eyes at fovea. Upright eyeless faces elicited largest N170 at nose fixation. Importantly, the N170 face inversion effect (FIE) was strongly attenuated in eyeless faces when fixation was on the eyes but was less attenuated for nose fixation and was normal when fixation was on the mouth. These results suggest the impact of eye removal on the N170 FIE is a function of the angular distance between the fixated feature and the eye location. We propose the Lateral Inhibition, Face Template and Eye Detector based (LIFTED) model which accounts for all the present N170 results including the FIE and its interaction with eye removal. Although eyes elicit the largest N170 response, reflecting the activity of an eye detector, the processing of upright faces is holistic and entails an inhibitory mechanism from neurons coding parafoveal information onto neurons coding foveal information. The LIFTED model provides a neuronal account of holistic and featural processing involved in upright and inverted faces and offers precise predictions for further testing.This study was supported by grants from the Natural Sciences and Engineering Research Council of Canada (NSERC Discovery Grant #418431)the Canada Foundation for Innovation (CFI)the Ontario Research Fund (ORF)and the Canada Research Chair program to RJI

    Precarious rock methodology for seismic hazard: Physical testing, numerical modeling and coherence studies

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    This report covers the following projects: Shake table tests of precarious rock methodology, field tests of precarious rocks at Yucca Mountain and comparison of the results with PSHA predictions, study of the coherence of the wave field in the ESF, and a limited survey of precarious rocks south of the proposed repository footprint. A series of shake table experiments have been carried out at the University of Nevada, Reno Large Scale Structures Laboratory. The bulk of the experiments involved scaling acceleration time histories (uniaxial forcing) from 0.1g to the point where the objects on the shake table overturned a specified number of times. The results of these experiments have been compared with numerical overturning predictions. Numerical predictions for toppling of large objects with simple contact conditions (e.g., I-beams with sharp basal edges) agree well with shake-table results. The numerical model slightly underpredicts the overturning of small rectangular blocks. It overpredicts the overturning PGA for asymmetric granite boulders with complex basal contact conditions. In general the results confirm the approximate predictions of previous studies. Field testing of several rocks at Yucca Mountain has approximately confirmed the preliminary results from previous studies, suggesting that the PSHA predictions are too high, possibly because the uncertainty in the mean of the attenuation relations. Study of the coherence of wavefields in the ESF has provided results which will be very important in design of the canisters distribution, in particular a preliminary estimate of the wavelengths at which the wavefields become incoherent. No evidence was found for extreme focusing by lens-like inhomogeneities. A limited survey for precarious rocks confirmed that they extend south of the repository, and one of these has been field tested

    Infrared Hall effect in high Tc superconductors: Evidence for non-Fermi liquid Hall scattering

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    Infrared (20-120 cm-1 and 900-1100 cm-1) Faraday rotation and circular dichroism are measured in high Tc superconductors using sensitive polarization modulation techniques. Optimally doped YBCO thin films are studied at temperatures down to 15 K and magnetic fields up to 8 T. At 1000 cm-1 the Hall conductivity varies strongly with temperature in contrast to the longitudinal conductivity which is nearly independent of temperature. The Hall scattering rate has a T^2 temperature dependence but, unlike a Fermi liquid, depends only weakly on frequency. The experiment puts severe constraints on theories of transport in the normal state of high Tc superconductors.Comment: 8 pages, 3 figure

    Epidemic space

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    The aim of this article is to highlight the importance of 'spatiality' in understanding the materialization of risk society and cultivation of risk sensibilities. More specifically it provides a cultural analysis of pathogen virulence (as a social phenomenon) by means of tracing and mapping the spatial flows that operate in the uncharted zones between the microphysics of infection and the macrophysics of epidemics. It will be argued that epidemic space consists of three types of forces: the vector, the index and the vortex. It will draw on Latour's Actor Network Theory to argue that epidemic space is geared towards instability when the vortex (of expanding associations and concerns) displaces the index (of finding a single cause)

    Magnetic field stabilization for high-accuracy mass measurements on exotic nuclides

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    The magnetic-field stability of a mass spectrometer plays a crucial role in precision mass measurements. In the case of mass determination of short-lived nuclides with a Penning trap, major causes of instabilities are temperature fluctuations in the vicinity of the trap and pressure fluctuations in the liquid helium cryostat of the superconducting magnet. Thus systems for the temperature and pressure stabilization of the Penning trap mass spectrometer ISOLTRAP at the ISOLDE facility at CERN have been installed. A reduction of the fluctuations by at least one order of magnitude downto dT=+/-5mK and dp=+/-50mtorr has been achieved, which corresponds to a relative frequency change of 2.7x10^{-9} and 1.5x10^{-10}, respectively. With this stabilization the frequency determination with the Penning trap only shows a linear temporal drift over several hours on the 10 ppb level due to the finite resistance of the superconducting magnet coils.Comment: 23 pages, 13 figure

    A low frequency multibeam assessment: Spatial mapping of shallow gas by enhanced penetration and angular response anomaly

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    This study highlights the potential of using a low frequency multibeam echosounder for detection and visualization of shallow gas occurring several meters beneath the seafloor. The presence of shallow gas was verified in the Bornholm Basin, Baltic Sea, at 80 m water depth with standard geochemical core analysis and hydroacoustic subbottom profiling. Successively, this area was surveyed with a 95 kHz and a 12 kHz multibeam echosounder (MBES). The bathymetric measurements with 12 kHz provided depth values systematically deeper by several meters compared to 95 kHz data. This observation was attributed to enhanced penetration of the low frequency signal energy into soft sediments. Consequently, the subbottom geoacoustic properties contributed highly to the measured backscattered signals. Those appeared up to 17 dB higher inside the shallow gas area compared to reference measurements outside and could be clearly linked to the shallow gas front depth down to 5 meter below seafloor. No elevated backscatter was visible in 95 kHz MBES data, which in turn highlights the superior potential of low frequency MBES to image shallow sub-seafloor features. Small gas pockets could be resolved even on the outer swath (up to 65°). Strongly elevated backscattering from gassy areas occurred at large incidence angles and a high gas sensitivity of the MBES is further supported by an angular response analysis presented in this study. We conclude that the MBES together with subbottom profiling can be used as an efficient tool for spatial subbottom mapping in soft sediment environments

    Regulation of vascular signalling by nuclear Sprouty2 in fetal lung epithelial cells:Implications for co-ordinated airway and vascular branching in lung development

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    This work was supported by a Wellcome Trust project grant 088032/Z/08/Z to SCL.Sprouty2 (Spry2) acts as a central regulator of tubular growth and branch patterning in the developing mammalian lung by controlling both magnitude and duration of growth factor signalling. To determine if this protein coordinates airway and vascular growth factor signalling, we tested the hypothesis that Spry2 links the primary cue for airway outgrowth, fibroblast growth factor-10 (FGF-10), to genomic events underpinning the expression and release of vascular endothelial growth factor-A (VEGF-A). Using primary fetal distal lung epithelial cells (FDLE) from rat, and immortalised human bronchial epithelial cells (16HBE14o-), we identified a nuclear sub-population of Spry2 which interacted with regions of the rat and human VEGF-A promoter spanning the hypoxia response element (HRE) and adjacent 3′ sites. In FDLE cultured at the PO2 of the fetal lung, FGF-10 relieved the Spry2 interaction at the HRE region by promoting clearance of a 39 kDa form and this was accompanied by histone-3 S10K14 phosphoacetylation, promoter de-methylation, hypoxia inducible factor-1α activation and VEGF-A expression. This repressive characteristic of nuclear Spry2 was relieved in 16HBE14o- by shRNA knockdown, and stable expression of mutants (C218A; C221A) that do not interact with the VEGF-A promoter HRE region. We conclude that nuclear Spry2 acts as a molecular link which co-ordinates airway and vascular growth of the cardiopulmonary system. This identifies Spry2 as a contributing determinant of design optimality in the mammalian lung.Publisher PDFPeer reviewe

    Priorities in Chronic nonbacterial osteomyelitis (CNO) - results from an international survey and roundtable discussions

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    ObjectiveChronic nonbacterial osteomyelitis (CNO) is an autoinflammatory bone disorder that predominantly affects children and young people. The pathophysiology and molecular mechanisms of CNO remain poorly understood, and diagnostic criteria and biomarkers are lacking. As a result, treatment is empiric and follows personal experience, case series and expert consensus plans.MethodsA survey was designed to gain insight on clinician and patient experiences of diagnosing and treating CNO and to collate opinions on research priorities. A version containing 24 questions was circulated among international expert clinicians and clinical academics (27 contacted, 21 responses). An equivalent questionnaire containing 20 questions was shared to explore the experience and priorities of CNO patients and family members (93 responses).ResultsResponses were used to select topics for four moderated roundtable discussions at the "International Conference on CNO and autoinflammatory bone disease" (Liverpool, United Kingdom, May 25-26th, 2022). The group identified deciphering the pathophysiology of CNO to be the highest priority, followed by clinical trials, necessary outcome measures and classification criteria. Surprisingly, mental wellbeing scored behind these items.ConclusionsAgreement exists among clinicians, academics, patients and families that deciphering the pathophysiology of CNO is of highest priority to inform clinical trials that will allow for the approval of medications for the treatment of CNO by regulatory agencies
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