147 research outputs found
Association between resting energy expenditure, psychopathology and HPA-axis in eating disorders.
Non-Contact Detection of Breathing Using a Microwave Sensor
In this paper the use of a continuous-wave microwave sensor as a non-contact tool for quantitative measurement of respiratory tidal volume has been evaluated by experimentation in seventeen healthy volunteers. The sensor working principle is reported and several causes that can affect its response are analyzed. A suitable data processing has been devised able to reject the majority of breath measurements taken under non suitable conditions. Furthermore, a relationship between microwave sensor measurements and volume inspired and expired at quiet breathing (tidal volume) has been found
What is Special K\"ahler Geometry ?
The scalars in vector multiplets of N=2 supersymmetric theories in 4
dimensions exhibit `special Kaehler geometry', related to duality symmetries,
due to their coupling to the vectors. In the literature there is some confusion
on the definition of special geometry. We show equivalences of some definitions
and give examples which show that earlier definitions are not equivalent, and
are not sufficient to restrict the Kaehler metric to one that occurs in N=2
supersymmetry. We treat the rigid as well as the local supersymmetry case. The
connection is made to moduli spaces of Riemann surfaces and Calabi-Yau 3-folds.
The conditions for the existence of a prepotential translate to a condition on
the choice of canonical basis of cycles.Comment: 46 pages, latex, no figures; 2 minor correction
Spectral Function of 2D Fermi Liquids
We show that the spectral function for single-particle excitations in a
two-dimensional Fermi liquid has Lorentzian shape in the low energy limit.
Landau quasi-particles have a uniquely defined spectral weight and a decay rate
which is much smaller than the quasi-particle energy. By contrast, perturbation
theory and the T-matrix approximation yield spurious deviations from Fermi
liquid behavior, which are particularly pronounced for a linearized dispersion
relation.Comment: 6 pages, LaTeX2e, 5 EPS figure
The rigid limit in Special Kahler geometry; From K3-fibrations to Special Riemann surfaces: a detailed case study
The limiting procedure of special Kahler manifolds to their rigid limit is
studied for moduli spaces of Calabi-Yau manifolds in the neighbourhood of
certain singularities. In two examples we consider all the periods in and
around the rigid limit, identifying the nontrivial ones in the limit as periods
of a meromorphic form on the relevant Riemann surfaces. We show how the Kahler
potential of the special Kahler manifold reduces to that of a rigid special
Kahler manifold. We extensively make use of the structure of these Calabi-Yau
manifolds as K3 fibrations, which is useful to obtain the periods even before
the K3 degenerates to an ALE manifold in the limit. We study various methods to
calculate the periods and their properties. The development of these methods is
an important step to obtain exact results from supergravity on Calabi-Yau
manifolds.Comment: 79 pages, 8 figures. LaTeX; typos corrected, version to appear in
Classical and Quantum Gravit
Spin and Charge Structure Factor of the 2-d Hubbard Model
The spin and charge structure factors are calculated for the Hubbard model on
the square lattice near half-filling using a spin-rotation invariant six-slave
boson representation. The charge structure factor shows a broad maximum at the
zone corner and is found to decrease monotonically with increasing interaction
strength and electron density and increasing temperature. The spin structure
factor develops with increasing interaction two incommensurate peaks at the
zone boundary and along the zone diagonal. Comparison with results of Quantum
Monte Carlo and variational calculations is carried out and the agreement is
found to be good. The limitations of an RPA-type approach are pointed out.Comment: 18 pages, revtex, 13 postscript figures, submitted to Phys. Rev.
Bactéria ou parasita? a controvérsia sobre a etiologia da doença do sono e a participação portuguesa, 1898-1904
Above-ground biomass prediction by Sentinel-1 multitemporal data in central Italy with integration of ALOS2 and Sentinel-2 data
Brain-derived proteins in the CSF, do they correlate with brain pathology in CJD?
BACKGROUND: Brain derived proteins such as 14-3-3, neuron-specific enolase (NSE), S 100b, tau, phosphorylated tau and Aβ(1–42 )were found to be altered in the cerebrospinal fluid (CSF) in Creutzfeldt-Jakob disease (CJD) patients. The pathogenic mechanisms leading to these abnormalities are not known, but a relation to rapid neuronal damage is assumed. No systematic analysis on brain-derived proteins in the CSF and neuropathological lesion profiles has been performed. METHODS: CSF protein levels of brain-derived proteins and the degree of spongiform changes, neuronal loss and gliosis in various brain areas were analyzed in 57 CJD patients. RESULTS: We observed three different patterns of CSF alteration associated with the degree of cortical and subcortical changes. NSE levels increased with lesion severity of subcortical areas. Tau and 14-3-3 levels increased with minor pathological changes, a negative correlation was observed with severity of cortical lesions. Levels of the physiological form of the prion protein (PrP(c)) and Aβ(1–42 )levels correlated negatively with cortical pathology, most clearly with temporal and occipital lesions. CONCLUSION: Our results indicate that the alteration of levels of brain-derived proteins in the CSF does not only reflect the degree of neuronal damage, but it is also modified by the localization on the brain pathology. Brain specific lesion patterns have to be considered when analyzing CSF neuronal proteins
Estratégia de crescimento clonal e fenologia de Syngonanthus chrysanthus Ruhland (Eriocaulaceae) nas baixadas entre dunas da Praia da Joaquina, Florianópolis, SC, Brasil
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