The facial feedback hypothesis suggests that an individual's experience of emotion is influenced by feedback from their facial movements. To evaluate the cumulative evidence for this hypothesis, we ...conducted a meta-analysis on 286 effect sizes derived from 138 studies that manipulated facial feedback and collected emotion self-reports. Using random effects meta-regression with robust variance estimates, we found that the overall effect of facial feedback was significant but small. Results also indicated that feedback effects are stronger in some circumstances than others. We examined 12 potential moderators, and 3 were associated with differences in effect sizes: (a) Type of emotional outcome: Facial feedback influenced emotional experience (e.g., reported amusement) and, to a greater degree, affective judgments of a stimulus (e.g., the objective funniness of a cartoon). Three publication bias detection methods did not reveal evidence of publication bias in studies examining the effects of facial feedback on emotional experience, but all 3 methods revealed evidence of publication bias in studies examining affective judgments. (b) Presence of emotional stimuli: Facial feedback effects on emotional experience were larger in the absence of emotionally evocative stimuli (e.g., cartoons). (c) Type of stimuli: When participants were presented with emotionally evocative stimuli, facial feedback effects were larger in the presence of some types of stimuli (e.g., emotional sentences) than others (e.g., pictures). The available evidence supports the facial feedback hypothesis' central claim that facial feedback influences emotional experience, although these effects tend to be small and heterogeneous.
Public Significance Statement
This meta-analysis suggests that posed emotional facial expressions influence self-reported emotional experience. However, the size of these effects varies and tends to be small.
In this paper we describe COLIN, a forward-chaining heuristic search planner, capable of reasoning with COntinuous LINear numeric change, in addition to the full temporal semantics of PDDL. Through ...this work we make two advances to the state-of-the-art in terms of expressive reasoning capabilities of planners: the handling of continuous linear change, and the handling of duration-dependent effects in combination with duration inequalities, both of which require tightly coupled temporal and numeric reasoning during planning. COLIN combines FF-style forward chaining search, with the use of a Linear Program (LP) to check the consistency of the interacting temporal and numeric constraints at each state. The LP is used to compute bounds on the values of variables in each state, reducing the range of actions that need to be considered for application. In addition, we develop an extension of the Temporal Relaxed Planning Graph heuristic of CRIKEY3, to support reasoning directly with continuous change. We extend the range of task variables considered to be suitable candidates for specifying the gradient of the continuous numeric change effected by an action. Finally, we explore the potential for employing mixed integer programming as a tool for optimising the timestamps of the actions in the plan, once a solution has been found. To support this, we further contribute a selection of extended benchmark domains that include continuous numeric effects. We present results for COLIN that demonstrate its scalability on a range of benchmarks, and compare to existing state-of-the-art planners.
Gravitational waves are expected to be radiated by supermassive black hole binaries formed during galaxy mergers. A stochastic superposition of gravitational waves from all such binary systems would ...modulate the arrival times of pulses from radio pulsars. Using observations of millisecond pulsars obtained with the Parkes radio telescope, we constrained the characteristic amplitude of this background, Ac,yr, to be <1.0 × 10–15 with 95% confidence. This limit excludes predicted ranges for Ac,yr from current models with 91 to 99.7% probability. We conclude that binary evolution is either stalled or dramatically accelerated by galactic-center environments and that higher-cadence and shorter-wavelength observations would be more sensitive to gravitational waves.
Abstract
Pulsar timing arrays aim to detect nanohertz-frequency gravitational waves (GWs). A background of GWs modulates pulsar arrival times and manifests as a stochastic process, common to all ...pulsars, with a signature spatial correlation. Here we describe a search for an isotropic stochastic gravitational-wave background (GWB) using observations of 30 millisecond pulsars from the third data release of the Parkes Pulsar Timing Array (PPTA), which spans 18 yr. Using current Bayesian inference techniques we recover and characterize a common-spectrum noise process. Represented as a strain spectrum
h
c
=
A
(
f
/
1
yr
−
1
)
α
, we measure
A
=
3.1
−
0.9
+
1.3
×
10
−
15
and
α
= −0.45 ± 0.20, respectively (median and 68% credible interval). For a spectral index of
α
= −2/3, corresponding to an isotropic background of GWs radiated by inspiraling supermassive black hole binaries, we recover an amplitude of
A
=
2.04
−
0.22
+
0.25
×
10
−
15
. However, we demonstrate that the apparent signal strength is time-dependent, as the first half of our data set can be used to place an upper limit on
A
that is in tension with the inferred common-spectrum amplitude using the complete data set. We search for spatial correlations in the observations by hierarchically analyzing individual pulsar pairs, which also allows for significance validation through randomizing pulsar positions on the sky. For a process with
α
= −2/3, we measure spatial correlations consistent with a GWB, with an estimated false-alarm probability of
p
≲ 0.02 (approx. 2
σ
). The long timing baselines of the PPTA and the access to southern pulsars will continue to play an important role in the International Pulsar Timing Array.
Pulsar timing array experiments search for phenomena that produce angular correlations in the arrival times of signals from millisecond pulsars. The primary goal is to detect an isotropic and ...stochastic gravitational wave background. We use simulated data to show that this search can be affected by the presence of other spatially correlated noise, such as errors in the reference time standard, errors in the planetary ephemeris, the solar wind and instrumentation issues. All these effects can induce significant false detections of gravitational waves. We test mitigation routines to account for clock errors, ephemeris errors and the solar wind. We demonstrate that it is non-trivial to find an effective mitigation routine for the planetary ephemeris and emphasize that other spatially correlated signals may be present in the data.
Magnetoencephalography (MEG) is a powerful technique for functional neuroimaging, offering a non-invasive window on brain electrophysiology. MEG systems have traditionally been based on cryogenic ...sensors which detect the small extracranial magnetic fields generated by synchronised current in neuronal assemblies, however, such systems have fundamental limitations. In recent years, non-cryogenic quantum-enabled sensors, called optically-pumped magnetometers (OPMs), in combination with novel techniques for accurate background magnetic field control, have promised to lift those restrictions offering an adaptable, motion-robust MEG system, with improved data quality, at reduced cost. However, OPM-MEG remains a nascent technology, and whilst viable systems exist, most employ small numbers of sensors sited above targeted brain regions. Here, building on previous work, we construct a wearable OPM-MEG system with ‘whole-head’ coverage based upon commercially available OPMs, and test its capabilities to measure alpha, beta and gamma oscillations. We design two methods for OPM mounting; a flexible (EEG-like) cap and rigid (additively-manufactured) helmet. Whilst both designs allow for high quality data to be collected, we argue that the rigid helmet offers a more robust option with significant advantages for reconstruction of field data into 3D images of changes in neuronal current. Using repeat measurements in two participants, we show signal detection for our device to be highly robust. Moreover, via application of source-space modelling, we show that, despite having 5 times fewer sensors, our system exhibits comparable performance to an established cryogenic MEG device. While significant challenges still remain, these developments provide further evidence that OPM-MEG is likely to facilitate a step change for functional neuroimaging.
•A 49-channel whole-head OPM-MEG system is constructed.•System evaluated via repeat measurements of alpha, beta and gamma oscillations.•Two OPM-helmet designs are contrasted, a flexible (EEG-like) cap and a rigid helmet.•The rigid helmet offers significant advantages for a viable OPM-MEG device.•49-channel OPM-MEG offers performance comparable to established cryogenic devices.
Continued timing observations of the double pulsar PSR J0737–3039A/B, which consists of two active radio pulsars (A and B) that orbit each other with a period of 2.45 h in a mildly eccentric ...(e=0.088) binary system, have led to large improvements in the measurement of relativistic effects in this system. With a 16-yr data span, the results enable precision tests of theories of gravity for strongly self-gravitating bodies and also reveal new relativistic effects that have been expected but are now observed for the first time. These include effects of light propagation in strong gravitational fields which are currently not testable by any other method. In particular, we observe the effects of retardation and aberrational light bending that allow determination of the spin direction of the pulsar. In total, we detect seven post-Keplerian parameters in this system, more than for any other known binary pulsar. For some of these effects, the measurement precision is now so high that for the first time we have to take higher-order contributions into account. These include the contribution of the A pulsar’s effective mass loss (due to spin-down) to the observed orbital period decay, a relativistic deformation of the orbit, and the effects of the equation of state of superdense matter on the observed post-Keplerian parameters via relativistic spin-orbit coupling. We discuss the implications of our findings, including those for the moment of inertia of neutron stars, and present the currently most precise test of general relativity’s quadrupolar description of gravitational waves, validating the prediction of general relativity at a level of 1.3×10^{-4} with 95% confidence. We demonstrate the utility of the double pulsar for tests of alternative theories of gravity by focusing on two specific examples and also discuss some implications of the observations for studies of the interstellar medium and models for the formation of the double pulsar system. Finally, we provide context to other types of related experiments and prospects for the future.
Rapid progress is being made in understanding the roles of the cerebral meninges in the maintenance of normal brain function, in immune surveillance, and as a site of disease. Most basic research on ...the meninges and the neural brain is now done on mice, major attractions being the availability of reporter mice with fluorescent cells, and of a huge range of antibodies useful for immunocytochemistry and the characterization of isolated cells. In addition, two-photon microscopy through the unperforated calvaria allows intravital imaging of the undisturbed meninges with sub-micron resolution. The anatomy of the dorsal meninges of the mouse (and, indeed, of all mammals) differs considerably from that shown in many published diagrams: over cortical convexities, the outer layer, the dura, is usually thicker than the inner layer, the leptomeninx, and both layers are richly vascularized and innervated, and communicate with the lymphatic system. A membrane barrier separates them and, in disease, inflammation can be localized to one layer or the other, so experimentalists must be able to identify the compartment they are studying. Here, we present current knowledge of the functional anatomy of the meninges, particularly as it appears in intravital imaging, and review their role as a gateway between the brain, blood, and lymphatics, drawing on information that is scattered among works on different pathologies.
ABSTRACT
High-resolution spectroscopy (HRS) has been used to detect a number of species in the atmospheres of hot Jupiters. Key to such detections is accurately and precisely modelled spectra for ...cross-correlation against the R ≳ 20 000 observations. There is a need for the latest generation of opacities which form the basis for high signal-to-noise detections using such spectra. In this study we present and make publicly available cross-sections for six molecular species, H2O, CO, HCN, CH4, NH3, and CO2 using the latest line lists most suitable for low- and high-resolution spectroscopy. We focus on the infrared (0.95–5 μm) and between 500 and 1500 K where these species have strong spectral signatures. We generate these cross-sections on a grid of pressures and temperatures typical for the photospheres of super-Earth, warm Neptunes, and hot Jupiters using the latest H2 and He pressure broadening. We highlight the most prominent infrared spectral features by modelling three representative exoplanets, GJ 1214 b, GJ 3470 b, and HD 189733 b, which encompass a wide range in temperature, mass, and radii. In addition, we verify the line lists for H2O, CO, and HCN with previous high-resolution observations of hot Jupiters. However, we are unable to detect CH4 with our new cross-sections from HRS observations of HD 102195 b. These high-accuracy opacities are critical for atmospheric detections with HRS and will be continually updated as new data become available.
The US Constitutions, both of 1788 and 1791, contain at Article IV (para 2, Section 3) a clause generally called The Fugitive Slave Clause. This Clause was held to make it legal to both recapture and ...return fugitive slaves to the states where they had lived or the owner, even if he or she resisted. The Clause was held to be constitutionally legal by lawyers and legal commentators. Even Lincoln as a lawyer thought the Clause was constitutionally legal, even though he thought slavery evil. Norman Coles presents arguments which show that the Clause has at least two (and possibly three) meanings. The Clause may not refer to slaves at all, when it is interpreted in accord with its actual phrasing rather than its intended meaning promoting the wishes of owners. Alvan Stewart, a renowned Abolitionist lawyer, argued that the Clause was inconsistent with that part of the 1791 US Constitution which is Amendment IV, reasoning premised on the definition of person, which applied to the two dated Constitutions; and with regard to the Fourth Amendment (1791) where slavery (unless a result of crime and jury trial) was illegal under US law. Stewarts arguments are about Constitutional principles, not the practical consequences of believing the Clause was law. Stewarts reasoning is penetrating; arguments relating to ambiguity and legal jargon are superseded by the logical consequence of the fact that if the Clause is about fugitive slaves, its legality rests on false assumptions. Herein lay the potential to avoid an historical tragedy. In the course of time legal and political champions, in conjunction with a growing number of US States, favoured laws which barred slave-hunting, but in the interim legal inadequacy resulted in the unnecessary continuation of slave-holding. This publication is a fundamental reconsideration of the intertwining of American History and American Constitutional Law.
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