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Biological Motion induced mu suppression is reduced in Early Psychosis (EP) patients with active negative symptoms and Autism Spectrum Disorders (ASD).
There is evidence of genetic and neural system overlap in Autism Spectrum Disorder (ASD) and Early Psychosis (EP). Five datasets were pooled to compare mu suppression index (MSI), a proxy of mirror neuron activity, in EP, high functioning ASD, and healthy subjects (HS). ASDs and EPs with "active" negative symptoms showed significant differences in mu suppression, in response to Biological Motion/point-light display animation, compared to HS. Preliminary findings suggest that similar neural network deficits in ASD and EP could be driven by the expression of negative symptoms in the latter group of patients. These findings may aid future studies on EP and ASD and facilitate the formulation of new hypotheses regarding their pathophysiology
Local modularity measure for network clusterizations
Many complex networks have an underlying modular structure, i.e., structural
subunits (communities or clusters) characterized by highly interconnected
nodes. The modularity has been introduced as a measure to assess the
quality of clusterizations. has a global view, while in many real-world
networks clusters are linked mainly \emph{locally} among each other
(\emph{local cluster-connectivity}). Here, we introduce a new measure,
localized modularity , which reflects local cluster structure. Optimization
of and on the clusterization of two biological networks shows that the
localized modularity identifies more cohesive clusters, yielding a
complementary view of higher granularity.Comment: 5 pages, 4 figures, RevTex4; Changed conten
Hydrogen-Accreting Carbon-Oxygen White Dwarfs of Low Mass: Thermal and Chemical Behavior of Burning Shells
Numerical experiments have been performed to investigate the thermal behavior
of a cooled down white dwarf of initial mass M_{\rm WD} = 0.516 M_{\sun}
which accretes hydrogen-rich matter with Z = 0.02 at the rate
\msun \yrm1, typical for a recurrent hydrogen shell flash regime. The evolution
of the main physical quantities of a model during a pulse cycle is examined in
detail. From selected models in the mass range
\msunend, we derive the borders in the - plane of the
steady state accretion regime when hydrogen is burned at a constant rate as
rapidly as it is accreted. The physical properties during a hydrogen shell
flash in white dwarfs accreting hydrogen-rich matter with metallicities Z =
0.001 and Z = 0.0001 are also studied. For a fixed accretion rate, a decrease
in the metallicity of the accreted matter leads to an increase in the thickness
of the hydrogen-rich layer at outburst and a decrease in the hydrogen-burning
shell efficiency. In the - plane, the borders of the
steady state accretion band are critically dependent on the metallicity of the
accreted matter: on decreasing the metallicity, the band is shifted to lower
accretion rates and its width in is reduced.Comment: 31 pages and 10 Postscript figures; Accepted for publication on Ap
Carbon-Oxygen White Dwarfs Accreting CO-Rich Matter I: A Comparison Between Rotating and Non-Rotating Models
We investigate the lifting effect of rotation on the thermal evolution of CO
WDs accreting CO-rich matter. We find that rotation induces the cooling of the
accreting star so that the delivered gravitational energy causes a greater
expansion with respect to the standard non-rotating case. The increase in the
surface radius produces a decrease in the surface value of the critical angular
velocity and, therefore, the accreting WD becomes gravitationally unbound
(Roche instability). This occurrence is due to an increase in the total angular
momentum of the accreting WD and depends critically on the amount of specific
angular momentum deposited by the accreted matter. If the specific angular
momentum of the accreted matter is equal to that of the outer layers of the
accreting structure, the Roche instability occurs well before the accreting WD
can attain the physical conditions for C-burning. If the values of both initial
angular velocity and accretion rate are small, we find that the accreting WD
undergoes a secular instability when its total mass approaches 1.4 Msun. At
this stage, the ratio between the rotational and the gravitational binding
energy of the WD becomes of the order of 0.1, so that the star must deform by
adopting an elliptical shape. In this case, since the angular velocity of the
WD is as large as 1 rad/s, the anisotropic mass distribution induces the loss
of rotational energy and angular momentum via GWR. We find that, independent of
the braking efficiency, the WD contracts and achieves the physical conditions
suitable for explosive C-burning at the center so that a type Ia supernova
event is produced.Comment: 39 pages, 22 eps-figures; accepted for publication in Astrophysical
Journa
Aortic coarctation in the elderly: how many errors lie behind an unexpected diagnosis?
A65-year-old woman was admitted to our department
because of chest pain and untreated hypertension. She had
been well until 6 years previously when a diagnosis of
hypertension was made. She reported poor control of blood
pressure associated with leg weakness in coincidence with
tentatively aggressive anti-hypertensive therapy. Aclinical diagnosis of aortic coarctation was made
[1], and a spiral TC study revealed a stenosis of the aorta
2 cm below the origin of the subclavia; a 2 cm aneurysm was present in the proximity of
the stenosis (Fig. 1, white arrow) and epiaortic arteries
were dilated
Affine equation of state from quintessence and k-essence fields
We explore the possibility that a scalar field with appropriate Lagrangian
can mimic a perfect fluid with an affine barotropic equation of state. The
latter can be thought of as a generic cosmological dark component evolving as
an effective cosmological constant plus a generalized dark matter. As such, it
can be used as a simple, phenomenological model for either dark energy or
unified dark matter. Furthermore, it can approximate (up to first order in the
energy density) any barotropic dark fluid with arbitrary equation of state. We
find that two kinds of Lagrangian for the scalar field can reproduce the
desired behaviour: a quintessence-like with a hyperbolic potential, or a purely
kinetic k-essence one. We discuss the behaviour of these two classes of models
from the point of view of the cosmological background, and we give some hints
on their possible clustering properties.Comment: 9 pages, 6 figures. Minor updates, accepted by CQ
Relationship between hypertension, diabetes and proteinuria in rural and urban households in Yemen
Little information is available on the meanings of proteinuria in low-resource settings. A population-based, cross-sectional survey was performed in Yemen on 10 242 subjects aged 15–69 years, stratified by age, gender and urban/rural residency. Hypertension is defined as systolic blood pressure (BP) of ⩾140 mm Hg and/or diastolic BP of ⩾90 mm Hg, and/or self-reported use of antihypertensive drugs; diabetes is diagnosed as fasting glucose of ⩾126 mg dl(−1) or self-reported use of hypoglycaemic medications; proteinuria is defined as ⩾+1 at dipstick urinalysis. Odds ratios (ORs) for associations were determined by multivariable logistic regression models. Prevalence (weighted to the Yemen population aged 15–69 years) of hypertension, diabetes and proteinuria were 7.5, 3.7 and 5.1% in urban, and 7.8, 2.6 and 7.3% in rural locations, respectively. Proteinuria and hypertension were more prevalent among rural dwellers (adjusted ORs 1.56; 95% confidence limit (Cl) 1.31–1.86, and 1.23; 1.08–1.41, respectively), diabetes being less prevalent in rural areas (0.70; 0.58–0.85). Differently from hypertension and diabetes, proteinuria was inversely related with age. Most importantly, 4.6 and 6.1% of urban and rural dwellers, respectively, had proteinuria in the absence of hypertension and diabetes. The approach of considering kidney damage as a consequence of hypertension and diabetes might limit the effectiveness of prevention strategies in low-income countries
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