4,974 research outputs found
Characterizing neuromorphologic alterations with additive shape functionals
The complexity of a neuronal cell shape is known to be related to its
function. Specifically, among other indicators, a decreased complexity in the
dendritic trees of cortical pyramidal neurons has been associated with mental
retardation. In this paper we develop a procedure to address the
characterization of morphological changes induced in cultured neurons by
over-expressing a gene involved in mental retardation. Measures associated with
the multiscale connectivity, an additive image functional, are found to give a
reasonable separation criterion between two categories of cells. One category
consists of a control group and two transfected groups of neurons, and the
other, a class of cat ganglionary cells. The reported framework also identified
a trend towards lower complexity in one of the transfected groups. Such results
establish the suggested measures as an effective descriptors of cell shape
Plurality Voting: the statistical laws of democracy in Brazil
We explore the statistical laws behind the plurality voting system by
investigating the election results for mayor held in Brazil in 2004. Our
analysis indicate that the vote partition among mayor candidates of the same
city tends to be "polarized" between two candidates, a phenomenon that can be
closely described by means of a simple fragmentation model. Complex concepts
like "government continuity" and "useful vote" can be identified and even
statistically quantified through our approach.Comment: 4 pages, 4 figure
Status of the HIE-ISOLDE project at CERN
The HIE-ISOLDE project represents a major upgrade of the ISOLDE nuclear
facility with a mandate to significantly improve the quality and increase the
intensity and energy of radioactive nuclear beams produced at CERN. The project
will expand the experimental nuclear physics programme at ISOLDE by focusing on
an upgrade of the existing Radioactive ion beam EXperiment (REX) linac with a
40 MV superconducting linac comprising thirty-two niobium-on-copper
sputter-coated quarter-wave resonators housed in six cryomodules. The new linac
will raise the energy of post-accelerated beams from 3 MeV/u to over 10 MeV/u.
The upgrade will be staged to first deliver beam energies of 5.5 MeV/u using
two high- cryomodules placed downstream of REX, before the energy
variable section of the existing linac is replaced with two low-
cryomodules and two additional high- cryomodules are installed to attain
over 10 MeV/u with full energy variability above 0.45 MeV/u. An overview of the
project including a status summary of the different R&D activities and the
schedule will outlined.Comment: 7 pages, 12 figures, submitted to the Heavy Ion Accelerator
Technology conference (HIAT) 2012, in Chicag
Hyperfine magnetic field in ferromagnetic graphite
Information on atomic-scale features is required for a better understanding
of the mechanisms leading to magnetism in non-metallic, carbon-based materials.
This work reports a direct evaluation of the hyperfine magnetic field produced
at 13C nuclei in ferromagnetic graphite by nuclear magnetic resonance (NMR).
The experimental investigation was made possible by the results of
first-principles calculations carried out in model systems, including graphene
sheets with atomic vacancies and graphite nanoribbons with edge sites partially
passivated by oxygen. A similar range of maximum hyperfine magnetic field
values (18-21T) was found for all systems, setting the frequency span to be
investigated in the NMR experiments; accordingly, a significant 13C NMR signal
was detected close to this range without any external applied magnetic field in
ferromagnetic graphite
Opinion and community formation in coevolving networks
In human societies opinion formation is mediated by social interactions,
consequently taking place on a network of relationships and at the same time
influencing the structure of the network and its evolution. To investigate this
coevolution of opinions and social interaction structure we develop a dynamic
agent-based network model, by taking into account short range interactions like
discussions between individuals, long range interactions like a sense for
overall mood modulated by the attitudes of individuals, and external field
corresponding to outside influence. Moreover, individual biases can be
naturally taken into account. In addition the model includes the opinion
dependent link-rewiring scheme to describe network topology coevolution with a
slower time scale than that of the opinion formation. With this model
comprehensive numerical simulations and mean field calculations have been
carried out and they show the importance of the separation between fast and
slow time scales resulting in the network to organize as well-connected small
communities of agents with the same opinion.Comment: 10 pages, 5 figures. New inset for Fig. 1 and references added.
Submitted to Physical Review
The informal social support for autonomy and dependence in pain inventory Spanish version
Social support plays a crucial role in the quality of life of people with chronic pain. The Informal Social Support for Autonomy and Dependence in Pain Inventory assesses two functions of received social support: the promotion of autonomy and the promotion of dependence. The aim of this cross-sectional study was to adapt this instrument for its use in the Spanish population. The sample comprised 256 individuals with chronic pain. Participants were recruited through two local associations of people with fibromyalgia, a physiotherapy unit and a hospital pain unit. The data were collected in Spain between October 2018 and January 2020. The structure of the questionnaire was analysed using confirmatory factor analysis, average variance extracted, composite reliability and internal consistency indexes, and inter-correlations between the scales. The criterion-related validity of the instrument was analysed by investigating its relationship with pain intensity, positive and negative affect, daily functioning, activity impairment, wellbeing and satisfaction with life. The structure with the best fit had four related factors: emotional social support for the promotion of autonomy; instrumental social support for the promotion of autonomy; emotional social support for the promotion of dependence and instrumental social support for the promotion of dependence. The scales showed adequate internal consistency. An association was found between higher levels of instrumental social support for the promotion of dependence and higher levels of pain-related disability and decreased daily functioning. An association was also found between the promotion of autonomy and increased satisfaction with life. The Spanish version of the inventory shows appropriate psychometric properties. In the setting of disability prevention, this instrument is useful in assessing the support relationships between people with chronic pain and their relatives.info:eu-repo/semantics/publishedVersio
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