251 research outputs found
Cable arrangement for rigid tethering Patent
Force separation rigid tethering device using cable
Correlations in the Far Infrared Background
We compute the expected angular power spectrum of the cosmic Far Infrared
Background (FIRB). We find that the signal due to source correlations dominates
the shot--noise for \ell \la 1000 and results in anisotropies with rms
amplitudes between 5% and 10% of the mean
for l \ga 150. The angular power spectrum depends on several unknown
quantities, such as the UV flux density evolution, optical properties of the
dust, biasing of the sources of the FIRB, and cosmological parameters. However,
when we require our models to reproduce the observed DC level of the FIRB, we
find that the anisotropy is at least a few percent in all cases. This
anisotropy is detectable with proposed instruments, and its measurement will
provide strong constraints on models of galaxy evolution and large-scale
structure at redshifts up to at least .Comment: 7 pages, 4 figures included, uses emulateapj.sty. More models
explored than in original version. Accepted for publication in Ap
Speech Prosody as a Bridge Between Psychopathology and Linguistics: The Case of the Schizophrenia Spectrum
Patients with schizophrenia spectrum disorders experience severe difficulties in interpersonal communication, as described by traditional psychopathology and current research on social cognition. From a linguistic perspective, pragmatic abilities are crucial for successful communication. Empirical studies have shown that these abilities are significantly impaired in this group of patients. Prosody, the tone of voice with which words and sentences are pronounced, is one of the most important carriers of pragmatic meaning and can serve a range of functions from linguistic to emotional ones. Most of the existing literature on prosody of patients with schizophrenia spectrum disorders focuses on the expression of emotion, generally showing significant impairments. By contrast, the use of non-emotional prosody in these patients is scarcely investigated. In this paper, we first present a linguistic model to classify prosodic functions. Second, we discuss existing studies on the use of non-emotional prosody in these patients, providing an overview of the state of the art. Third, we delineate possible future lines of research in this field, also taking into account some classical psychopathological assumptions, for both diagnostic and therapeutic purposes
Distinct neural correlates of social and object reward seeking motivation
open access articleThe “Choose‐a‐Movie‐CAM” is an established task to quantify the motivation for seeking social rewards. It allows participants to directly assess both the stimulus value and the effort required to obtain it. In the present study, we aimed to identify the neural mechanisms of such cost‐benefit decision‐making. To this end, functional Magnetic Resonance Imaging data were collected from 24 typical adults while they completed the CAM task. We partly replicated the results from our previous behavioural studies showing that typical adults prefer social over object stimuli and low effort over higher effort stimuli but found no interaction between the two. Results from neuroimaging data suggest that there are distinct neural correlates for social and object preferences. The precuneus and medial orbitofrontal cortex, two key areas involved in social processing are engaged when participants make a social choice. Areas of the ventral and dorsal stream pathways associated with object recognition are engaged when making an object choice. These activations can be seen during the decision phase even before the rewards have been consumed, indicating a transfer the hedonic properties of social stimuli to its cues. We also found that the left insula and bilateral clusters in the inferior occipital gyrus and the inferior parietal lobule were recruited for increasing effort investment. We discuss limitations and implications of this study which reveals the distinct neural correlates for social and object rewards, using a robust behavioural measure of social motivation
On an Analytical Framework for Voids: Their abundances, density profiles and local mass functions
We present a general analytical procedure for computing the number density of
voids with radius above a given value within the context of gravitational
formation of the large scale structure of the universe out of Gaussian initial
conditions. To this end we develop an accurate (under generally satisfied
conditions) extension of unconditional mass function to constrained
environments, which allowes us both to obtain the number density of collapsed
objects of certain mass at any distance from the center of the void, and to
derive the number density of voids defined by those collapsed objects. We have
made detailed calculations for the spherically averaged mass density and halo
number density profiles for individual voids. We also present a formal
expression for the number density of voids defined by galaxies of a given type
and luminosity. This expression contains the probability for a collapsed object
of certain mass to host a galaxy of that type and luminosity as a function of
the environmental density. We propose a procedure to infer this function, which
may provide useful clues as to the galaxy formation process, from the observed
void densities.Comment: 14 pages, 7 figures, MNRAS in pres
Topology of structure in the Sloan Digital Sky Survey: model testing
We measure the three-dimensional topology of large-scale structure in the
Sloan Digital Sky Survey (SDSS). This allows the genus statistic to be measured
with unprecedented statistical accuracy. The sample size is now sufficiently
large to allow the topology to be an important tool for testing galaxy
formation models. For comparison, we make mock SDSS samples using several
state-of-the-art N-body simulations: the Millennium run of Springel et al.
(2005)(10 billion particles), Kim & Park (2006) CDM models (1.1 billion
particles), and Cen & Ostriker (2006) hydrodynamic code models (8.6 billion
cell hydro mesh). Each of these simulations uses a different method for
modeling galaxy formation. The SDSS data show a genus curve that is broadly
characteristic of that produced by Gaussian random phase initial conditions.
Thus the data strongly support the standard model of inflation where Gaussian
random phase initial conditions are produced by random quantum fluctuations in
the early universe. But on top of this general shape there are measurable
differences produced by non-linear gravitational effects (cf. Matsubara 1994),
and biasing connected with galaxy formation. The N-body simulations have been
tuned to reproduce the power spectrum and multiplicity function but not
topology, so topology is an acid test for these models. The data show a
``meatball'' shift (only partly due to the Sloan Great Wall of Galaxies; this
shift also appears in a sub-sample not containing the Wall) which differs at
the 2.5\sigma level from the results of the Millennium run and the Kim & Park
dark halo models, even including the effects of cosmic variance.Comment: 13 Apj pages, 7 figures High-resolution stereo graphic available at
http://www.astro.princeton.edu/~dclayh/stereo50.ep
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Spring School on Language, Music, and Cognition: Organizing Events in Time
The interdisciplinary spring school “Language, music, and cognition: Organizing events in time” was held from February 26 to March 2, 2018 at the Institute of Musicology of the University of Cologne. Language, speech, and music as events in time were explored from different perspectives including evolutionary biology, social cognition, developmental psychology, cognitive neuroscience of speech, language, and communication, as well as computational and biological approaches to language and music. There were 10 lectures, 4 workshops, and 1 student poster session.
Overall, the spring school investigated language and music as neurocognitive systems and focused on a mechanistic approach exploring the neural substrates underlying musical, linguistic, social, and emotional processes and behaviors. In particular, researchers approached questions concerning cognitive processes, computational procedures, and neural mechanisms underlying the temporal organization of language and music, mainly from two perspectives: one was concerned with syntax or structural representations of language and music as neurocognitive systems (i.e., an intrapersonal perspective), while the other emphasized social interaction and emotions in their communicative function (i.e., an interpersonal perspective). The spring school not only acted as a platform for knowledge transfer and exchange but also generated a number of important research questions as challenges for future investigations
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