1,558 research outputs found
Requirements for Robotic Interpretation of Social Signals “in the Wild”: Insights from Diagnostic Criteria of Autism Spectrum Disorder
The last few decades have seen widespread advances in technological means to characterise
observable aspects of human behaviour such as gaze or posture. Among others, these developments
have also led to significant advances in social robotics. At the same time, however, social robots
are still largely evaluated in idealised or laboratory conditions, and it remains unclear whether
the technological progress is sufficient to let such robots move “into the wild”. In this paper, we
characterise the problems that a social robot in the real world may face, and review the technological
state of the art in terms of addressing these. We do this by considering what it would entail
to automate the diagnosis of Autism Spectrum Disorder (ASD). Just as for social robotics, ASD
diagnosis fundamentally requires the ability to characterise human behaviour from observable
aspects. However, therapists provide clear criteria regarding what to look for. As such, ASD diagnosis
is a situation that is both relevant to real-world social robotics and comes with clear metrics. Overall,
we demonstrate that even with relatively clear therapist-provided criteria and current technological
progress, the need to interpret covert behaviour cannot yet be fully addressed. Our discussions have
clear implications for ASD diagnosis, but also for social robotics more generally. For ASD diagnosis,
we provide a classification of criteria based on whether or not they depend on covert information
and highlight present-day possibilities for supporting therapists in diagnosis through technological
means. For social robotics, we highlight the fundamental role of covert behaviour, show that the
current state-of-the-art is unable to characterise this, and emphasise that future research should tackle
this explicitly in realistic settings
Hard squares with negative activity
We show that the hard-square lattice gas with activity z= -1 has a number of
remarkable properties. We conjecture that all the eigenvalues of the transfer
matrix are roots of unity. They fall into groups (``strings'') evenly spaced
around the unit circle, which have interesting number-theoretic properties. For
example, the partition function on an M by N lattice with periodic boundary
condition is identically 1 when M and N are coprime. We provide evidence for
these conjectures from analytical and numerical arguments.Comment: 8 page
Competing density-wave orders in a one-dimensional hard-boson model
We describe the zero-temperature phase diagram of a model of bosons,
occupying sites of a linear chain, which obey a hard-exclusion constraint: any
two nearest-neighbor sites may have at most one boson. A special case of our
model was recently proposed as a description of a ``tilted'' Mott insulator of
atoms trapped in an optical lattice. Our quantum Hamiltonian is shown to
generate the transfer matrix of Baxter's hard-square model. Aided by exact
solutions of a number of special cases, and by numerical studies, we obtain a
phase diagram containing states with long-range density-wave order with period
2 and period 3, and also a floating incommensurate phase. Critical theories for
the various quantum phase transitions are presented. As a byproduct, we show
how to compute the Luttinger parameter in integrable theories with
hard-exclusion constraints.Comment: 16 page
Lattice Models with N=2 Supersymmetry
We introduce lattice models with explicit N=2 supersymmetry. In these
interacting models, the supersymmetry generators Q^+ and Q^- yield the
Hamiltonian H={Q^+,Q^-} on any graph. The degrees of freedom can be described
as either fermions with hard cores, or as quantum dimers. The Hamiltonian of
our simplest model contains a hopping term and a repulsive potential, as well
as the hard-core repulsion. We discuss these models from a variety of
perspectives: using a fundamental relation with conformal field theory, via the
Bethe ansatz, and using cohomology methods. The simplest model provides a
manifestly-supersymmetric lattice regulator for the supersymmetric point of the
massless 1+1-dimensional Thirring (Luttinger) model. We discuss the
ground-state structure of this same model on more complicated graphs, including
a 2-leg ladder, and discuss some generalizations.Comment: 4 page
Pain and physical functioning in neuropathic pain: a systematic review of psychometric properties of various outcome measures
INTRODUCTION:
A range of outcome measures across various domains are used to evaluate change following an intervention in clinical trials on chronic neuropathic pain (NeP). However, to capture a real change in the variable of interest, the psychometric properties of a particular measure should demonstrate appropriate methodological quality. Various outcome measures in the domains of pain and physical functioning have been used in the literature for NeP, for which individual properties (eg, reliability/validity) have been reported. To date, there is no definitive synthesis of evidence on the psychometric properties of those outcome measures; thus, the aim of this systematic review was to evaluate the methodological quality [COnsensus-based Standards for the selection of health status Measurement INstruments (COSMIN) guidelines] of studies that evaluated psychometric properties of pain and physical functioning outcome measures used for NeP.
METHODS:
Specific MeSH/keywords related to 3 areas (pain and/or physical functioning, psychometric properties, and NeP) were used to retrieve relevant studies (English language) in key electronic databases (MEDLINE (Ovid), CINAHL (EBSCO), Scopus, AMED, and Web of Science) from database inception-July 2012. Articles retrieval/screening and quality analysis (COSMIN) were carried out by 2 independent reviewers.
RESULTS:
Twenty-four pain and thirty-seven physical functioning outcome measures were identified, varying in methodological quality from poor-excellent.
CONCLUSION:
Although a variety of pain and physical functioning outcome measures have been reported in the literature, few have demonstrate methodologically strong psychometric properties. Thus, future research is required to further investigate the psychometric properties of existing pain and physical functioning outcome measures used for clinical and research purposes
Loop models and their critical points
Loop models have been widely studied in physics and mathematics, in problems
ranging from polymers to topological quantum computation to Schramm-Loewner
evolution. I present new loop models which have critical points described by
conformal field theories. Examples include both fully-packed and dilute loop
models with critical points described by the superconformal minimal models and
the SU(2)_2 WZW models. The dilute loop models are generalized to include
SU(2)_k models as well.Comment: 20 pages, 15 figure
Order Parameters of the Dilute A Models
The free energy and local height probabilities of the dilute A models with
broken \Integer_2 symmetry are calculated analytically using inversion and
corner transfer matrix methods. These models possess four critical branches.
The first two branches provide new realisations of the unitary minimal series
and the other two branches give a direct product of this series with an Ising
model. We identify the integrable perturbations which move the dilute A models
away from the critical limit. Generalised order parameters are defined and
their critical exponents extracted. The associated conformal weights are found
to occur on the diagonal of the relevant Kac table. In an appropriate regime
the dilute A model lies in the universality class of the Ising model in a
magnetic field. In this case we obtain the magnetic exponent
directly, without the use of scaling relations.Comment: 53 pages, LaTex, ITFA 93-1
Pituitary adenylate cyclase-activating peptide induces long-lasting neuroprotection through the induction of activity-dependent signaling via the cyclic AMP response element-binding protein-regulated transcription co-activator 1
Pituitary adenylate cyclase-activating peptide (PACAP) is a neuroprotective peptide which exerts its effects mainly through the cAMP-protein kinase A (PKA) pathway. Here, we show that in cortical neurons, PACAP-induced PKA signaling exerts a major part of its neuroprotective effects indirectly, by triggering action potential (AP) firing. Treatment of cortical neurons with PACAP induces a rapid and sustained PKA-dependent increase in AP firing and associated intracellular Ca(2+) transients, which are essential for the anti-apoptotic actions of PACAP. Transient exposure to PACAP induces long-lasting neuroprotection in the face of apoptotic insults which is reliant on AP firing and the activation of cAMP response element (CRE) binding protein (CREB)-mediated gene expression. Although direct, activity-independent PKA signaling is sufficient to trigger phosphorylation on CREB’s activating serine-133 site, this is insufficient for activation of CREB-mediated gene expression. Full activation is dependent on CREB-regulated transcription co-activator 1 (CRTC1), whose PACAP-induced nuclear import is dependent on firing activity-dependent calcineurin signaling. Over-expression of CRTC1 is sufficient to rescue PACAP-induced CRE-mediated gene expression in the face of activity-blockade, while dominant negative CRTC1 interferes with PACAP-induced, CREB-mediated neuroprotection. Thus, the enhancement of AP firing may play a significant role in the neuroprotective actions of PACAP and other adenylate cyclase-coupled ligands
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