673 research outputs found
In Play We Trust. Rapid Facial Mimicry Predicts the Duration of Playful Interactions in Geladas
The primate play-face is homologous to the human facial display accompanying laughter. Through facial mimicry, the playface evokes in the perceiver a similar positive emotional state. This sensorimotor and emotional sharing can be adaptive, as it allows individuals to fine-tune their own motor sequences accordingly thus increasing cooperation in play. It has been recently demonstrated that, not only humans and apes, but also geladas are able to mimic others\u27 facial expressions. Here, we describe two forms of facial mimicry in Theropithecus gelada: rapid (RFM, within 1.0 s) and delayed (DFM, within 5.0 s). Play interactions characterized by the presence of RFM were longer than those with DFM thus suggesting that RFM is a good indicator of the quality of communicative exchanges and behavioral coordination. These findings agree with the proposal of a mirror mechanism operating during perception and imitation of facial expressions. In an evolutionary perspective, our findings suggest that RFM not only was already present in the common ancestor of cercopitecoids and hominoids, but also that there is a relationship between RFM and length and quality of playful interactions
Different yawns, different functions? Testing social hypotheses on spontaneous yawning in Theropithecus gelada
Here, we tested hypotheses about the potential functions of yawning based on its intensity and social contexts. Due to their spectrum intensity of yawns (covered teeth/YW1; uncovered teeth/YW2; uncovered gums/YW3), geladas are a good model species for this purpose. We suggest that yawns of different intensity can bear different information according to the performer, the context and the behavioural pattern temporally associated to the yawn event. YW3, mainly performed by high ranking males during periods of high social tension, was frequently associated with an auditory component and often accompanied by scratching (a measure of anxiety). YW1 and YW2, preferentially performed by females, were frequently associated to lip smacking, an affiliative display. In conclusion, even though a clear-cut functional distinction of geladas\u27 yawn intensity is difficult, YW1 and YW2 seem to be more linked to affiliative social interactions; whereas, YW3 seems to be more linked to agonistic and tension situations
Detection methods for non-Gaussian gravitational wave stochastic backgrounds
We address the issue of finding an optimal detection method for a
discontinuous or intermittent gravitational wave stochastic background. Such a
signal might sound something like popcorn popping. We derive an appropriate
version of the maximum likelihood detection statistic, and compare its
performance to that of the standard cross-correlation statistic both
analytically and with Monte Carlo simulations. The maximum likelihood statistic
performs better than the cross-correlation statistic when the background is
sufficiently non-Gaussian. For both ground and space based detectors, this
results in a gain factor, ranging roughly from 1 to 3, in the minimum
gravitational-wave energy density necessary for detection, depending on the
duty cycle of the background. Our analysis is exploratory, as we assume that
the time structure of the events cannot be resolved, and we assume white,
Gaussian noise in two collocated, aligned detectors. Before this detection
method can be used in practice with real detector data, further work is
required to generalize our analysis to accommodate separated, misaligned
detectors with realistic, colored, non-Gaussian noise.Comment: 25 pages, 12 figures, submitted to physical review D, added revisions
in response to reviewers comment
The mu-rhythm can mirror: Insights from experimental design, and looking past the controversy.
Development Psychopathology in context: famil
Cyclooxygenase 2, toll-like receptor 4 and interleukin 1beta mRNA expression in atherosclerotic plaques of type 2 diabetic patients.
Objectives and design: Inflammation has a prominent role in the development of atherosclerosis. Type 2 diabetes could contribute to atherosclerosis development by promoting inflammation. This status might accelerate changes in intrinsic vascular wall cells and favor plaque formation. Cyclooxygenase 2 (COX-2) is highly expressed in atherosclerotic plaques. COX-2 gene expression is promoted through activation of toll-like receptor 4 (TLR4) and pro-inflammatory cytokine interleukin 1\u3b2 (IL1-\u3b2). Aim of this study is to investigate whether expression profiles of pro-inflammatory genes such as COX-2, TLR4 and IL1-\u3b2 in atherosclerotic plaques are altered in type 2 diabetes (T2D).Methods: Total RNA was isolated from plaques of atherosclerotic patients and expression of COX-2, TLR4, IL1-\u3b2 analyzed using real-time PCR. Histological analysis was performed on sections of the plaque to establish the degree of instability.Results: Statistically significant differences in mRNA expression of COX-2 and IL1-\u3b2 were found in plaques of T2D compared with non-T2D patients. A multi-variable linear regression model suggests that COX-2 mRNA expression is affected by T2D pathology and IL1-\u3b2 mRNA expression in atherosclerotic plaques.Conclusions: Our results support the hypothesis that T2D pathology contributes in vivo to increase the inflammatory process associated with the atherosclerotic plaque formation, as shown by an increment of COX-2 and IL1-\u3b2 mRNA expression
System Test of the ATLAS Muon Spectrometer in the H8 Beam at the CERN SPS
An extensive system test of the ATLAS muon spectrometer has been performed in
the H8 beam line at the CERN SPS during the last four years. This spectrometer
will use pressurized Monitored Drift Tube (MDT) chambers and Cathode Strip
Chambers (CSC) for precision tracking, Resistive Plate Chambers (RPCs) for
triggering in the barrel and Thin Gap Chambers (TGCs) for triggering in the
end-cap region. The test set-up emulates one projective tower of the barrel
(six MDT chambers and six RPCs) and one end-cap octant (six MDT chambers, A CSC
and three TGCs). The barrel and end-cap stands have also been equipped with
optical alignment systems, aiming at a relative positioning of the precision
chambers in each tower to 30-40 micrometers. In addition to the performance of
the detectors and the alignment scheme, many other systems aspects of the ATLAS
muon spectrometer have been tested and validated with this setup, such as the
mechanical detector integration and installation, the detector control system,
the data acquisition, high level trigger software and off-line event
reconstruction. Measurements with muon energies ranging from 20 to 300 GeV have
allowed measuring the trigger and tracking performance of this set-up, in a
configuration very similar to the final spectrometer. A special bunched muon
beam with 25 ns bunch spacing, emulating the LHC bunch structure, has been used
to study the timing resolution and bunch identification performance of the
trigger chambers. The ATLAS first-level trigger chain has been operated with
muon trigger signals for the first time
Installazione di 5 stazioni digitali a larga-banda sullâisola di vulcano: un contributo alla conoscenza della sismicitĂ superficiale della fossa
Earthquakes beneath Vulcano (Aeolian Island, Italy) are associated with fracturing (single events and sporadic swarms of low magnitude) or related to processes of the geothermal system (Montalto, 1994). This latter processes is responsible for most of the background activity, which is represented by weak events originating at shallow depth under the La Fossa cone (H<1.5 Km below sea level).
In order to improved the Permanent Seismic Network (PSN) run by Catania Section of Istituto Nazionale di Geofisica e Vulcanologia (INGV-CT) by installing additional 5 broad-band stations surrounding the La Fossa crater, to. In particular, on November 2005 along the north rim of La Fossa cone, 3 digital stations were installed with an array configuration; thereafter, in spring 2007 another two stations were installed at the southern base of the cone. All the stations are currently in continual transmission with Lipari Observatory.
We considered about 1200 micro-earthquakes recorded from January 2004 to July 2007 associated with fluid dynamics processes.
Studying 1007 of these events, six classes of events have been recognized by visual inspection, spectral and cross correlation analyses. Three episodes of increasing occurrence accompanying geothermal and geochemical anomalies have been recorded during this time period.
The improved seismic network allowed the location of 55 events with unprecedented resolution and to highlight a space distribution depending on the classes of events.
The events are located in the central and south-oriental sector of the cone at 500-1000 meter b.s.l. depth and events of each class seem clustering in preferential sectors.Published1-161.5. TTC - Sorveglianza dell'attivitĂ eruttiva dei vulcaniN/A or not JCRope
Neutron cross-sections for advanced nuclear systems : The n-TOF project at CERN
© Owned by the authors, published by EDP Sciences, 2014 This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly citedThe study of neutron-induced reactions is of high relevance in a wide variety of fields, ranging from stellar nucleosynthesis and fundamental nuclear physics to applications of nuclear technology. In nuclear energy, high accuracy neutron data are needed for the development of Generation IV fast reactors and accelerator driven systems, these last aimed specifically at nuclear waste incineration, as well as for research on innovative fuel cycles. In this context, a high luminosity Neutron Time Of Flight facility, n-TOF, is operating at CERN since more than a decade, with the aim of providing new, high accuracy and high resolution neutron cross-sections. Thanks to the features of the neutron beam, a rich experimental program relevant to nuclear technology has been carried out so far. The program will be further expanded in the near future, thanks in particular to a new high-flux experimental area, now under construction.Peer reviewedFinal Published versio
238U(n, Îł) reaction cross section measurement with C 6D6 detectors at the n-TOF CERN facility
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 2.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly citedThe radiative capture cross section of 238U is very important for the developing of new reactor technologies and the safety of existing ones. Here the preliminary results of the 238U(n,Îł) cross section measurement performed at n-TOF with C6D6 scintillation detectors are presented, paying particular attention to data reduction and background subtraction.Peer reviewe
Measurement of the branching fraction for the decay KS --> pi e nu
We present a measurement of the branching ratio BR(KS --> pi e nu) performed
using the KLOE detector. KS mesons are produced in the reaction e+ e- --> phi
--> KS KL at the DAFNE collider. In a sample of about 5 million KS-tagged
events we find 624 +- 30 semileptonic KS decays. Normalizing to the KS --> pi+
pi- count in the same data sample, we obtain BR(KS --> pi e nu) = (6.91 +-
0.37) 10^-4, in agreement with the Standard Model expectation.Comment: 9 pages, 5 Encapsulated Postscript figures. Submitted to Phys. Lett.
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