Attachment, Physiological and Familial Vulnerability in Childhood Obesity: an Interactive Multisystem Approach

The aims of the present study were to test the association between insecure attachment and basal cortisol and catecholamines levels in a sample of obese children. The role of familial vulnerability and gender was also investigated. Methods: Cortisol and catecholamines levels of 8- to 13-year olds obese children were measured. Self-report questionnaires were used to assess attachment pattern and current anxiety and depression, and parent-report questionnaires were used to assess attachment, current anxiety and depression and familial vulnerability. Linear regression analyses were performed for individuals that scored low versus high on parental internalizing problems, and for boys and girls, separately. Results: In the group with high parental internalizing problems, insecure attachment was significantly associated with reduced basal levels of cortisol, in boys (p=0.007, b= -0.861, R2= 73.0%). In the group with low parental internalizing problems, the association between insecure attachment and cortisol was not significant in either boys or girls, and it was negative in boys (p=0.075, b= -0.606, R2= 36.7%) and positive in girls (p=0.677, b= 0.176, R2= 3.1%) . Conclusions: Apparently, physiological risk factors for psicopathology in obesity are more evident in individuals with a high familial vulnerability. In addition, patterns of physiological risk for psicopathology in obesity are different in boys and girls. Therefore, it is important to take into account familial vulnerability and gender when investigating physiological risk factors for psycopathology in obesity. Insecure attachment in childhood may be a risk factor for obesity. Interventions to increase children's attachment security should examine the effects on children's weight

On the quantumness of correlations in nuclear magnetic resonance

Nuclear Magnetic Resonance (NMR) was successfully employed to test several protocols and ideas in Quantum Information Science. In most of these implementations the existence of entanglement was ruled out. This fact introduced concerns and questions about the quantum nature of such bench tests. In this article we address some issues related to the non-classical aspects of NMR systems. We discuss some experiments where the quantum aspects of this system are supported by quantum correlations of separable states. Such quantumness, beyond the entanglement-separability paradigm, is revealed via a departure between the quantum and the classical versions of information theory. In this scenario, the concept of quantum discord seems to play an important role. We also present an experimental implementation of an analogous of the single-photon Mach-Zehnder interferometer employing two nuclear spins to encode the interferometric paths. This experiment illustrate how non-classical correlations of separable states may be used to simulate quantum dynamics. The results obtained are completely equivalent to the optical scenario, where entanglement (between two field modes) may be present

A 'p-n' diode with hole and electron-doped lanthanum manganite

The hole-doped manganite La0.7Ca0.3MnO3 and the electron-doped manganite La0.7Ce0.3MnO3 undergo an insulator to metal transition at around 250 K, above which both behave as a polaronic semiconductor. We have successfully fabricated an epitaxial trilayer (La0.7Ca0.3MnO3/SrTiO3/La0.7Ce0.3MnO3), where SrTiO3 is an insulator. At room temperature, i.e. in the semiconducting regime, it exhibits asymmetric current-voltage (I-V) characteristics akin to a p-n diode. The observed asymmetry in the I-V characteristics disappears at low temperatures where both the manganite layers are metallic. To the best of our knowledge, this is the first report of such a p-n diode, using the polaronic semiconducting regime of doped manganites.Comment: PostScript text and 2 figures, to be published in Appl. Phys. Lett

Water activity in lamellar stacks of lipid bilayers: "Hydration forces" revisited

Water activity and its relationship with interactions stabilising lamellar stacks of mixed lipid bilayers in their fluid state are investigated by means of osmotic pressure measurements coupled with small-angle x-ray scattering. The (electrically-neutral) bilayers are composed of a mixture in various proportions of lecithin, a zwitterionic phospholipid, and Simulsol, a non-ionic cosurfactant with an ethoxylated polar head. For highly dehydrated samples the osmotic pressure profile always exhibits the "classical" exponential decay as hydration increases but, depending on Simulsol to lecithin ratio, it becomes either of the "bound" or "unbound" types for more water-swollen systems. A simple thermodynamic model is used for interpreting the results without resorting to the celebrated but elusive "hydration forces"Comment: 24 pages, 12 figures. Accepted for publication in The European Physical Journal

Nonclassical correlation in NMR quadrupolar systems

The existence of quantum correlation (as revealed by quantum discord), other than entanglement and its role in quantum-information processing (QIP), is a current subject for discussion. In particular, it has been suggested that this nonclassical correlation may provide computational speedup for some quantum algorithms. In this regard, bulk nuclear magnetic resonance (NMR) has been successfully used as a test bench for many QIP implementations, although it has also been continuously criticized for not presenting entanglement in most of the systems used so far. In this paper, we report a theoretical and experimental study on the dynamics of quantum and classical correlations in an NMR quadrupolar system. We present a method for computing the correlations from experimental NMR deviation-density matrices and show that, given the action of the nuclear-spin environment, the relaxation produces a monotonic time decay in the correlations. Although the experimental realizations were performed in a specific quadrupolar system, the main results presented here can be applied to whichever system uses a deviation-density matrix formalism.Comment: Published versio

A high-density relativistic reflection origin for the soft and hard X-ray excess emission from Mrk 1044

We present the first results from a detailed spectral-timing analysis of a long ($\sim$130 ks) XMM-Newton observation and quasi-simultaneous NuSTAR and Swift observations of the highly-accreting narrow-line Seyfert 1 galaxy Mrk 1044. The broadband (0.3$-$50 keV) spectrum reveals the presence of a strong soft X-ray excess emission below $\sim$1.5 keV, iron K$_{\alpha}$ emission complex at $\sim$6$-$7 keV and a `Compton hump' at $\sim$15$-$30 keV. We find that the relativistic reflection from a high-density accretion disc with a broken power-law emissivity profile can simultaneously explain the soft X-ray excess, highly ionized broad iron line and the Compton hump. At low frequencies ($[2-6]\times10^{-5}$ Hz), the power-law continuum dominated 1.5$-$5 keV band lags behind the reflection dominated 0.3$-$1 keV band, which is explained with a combination of propagation fluctuation and Comptonization processes, while at higher frequencies ($[1-2]\times10^{-4}$ Hz), we detect a soft lag which is interpreted as a signature of X-ray reverberation from the accretion disc. The fractional root-mean-squared (rms) variability of the source decreases with energy and is well described by two variable components: a less variable relativistic disc reflection and a more variable direct coronal emission. Our combined spectral-timing analyses suggest that the observed broadband X-ray variability of Mrk~1044 is mainly driven by variations in the location or geometry of the optically thin, hot corona.Comment: 23 pages, 19 figures, 4 tables, Published in MNRA

Optical study on doped polyaniline composite films

Localization driven by disorder has a strong influence on the conducting property of conducting polymer. A class of authors hold the opinion that disorder in the material is homogeneous and conducting polymer is disordered metal close to Anderson-Mott Metal-Insulator transition, while others treat the disorder as inhomogeneous and have the conclusion that conducting polymer is a composite of ordered metallic regions and disordered insulating regions. The morphology of conducting polymers is an important factor that have influence on the type and extent of disorder. Different protonic acids used as dopants and moisture have affection on polymer chain arrangement and interchain interactions. A PANI-CSA film, two PANI-CSA/PANI-DBSA composite films with different dopants ratio, and one of the composite films with different moisture content are studied. Absolute reflectivity measurements are performed on the films. Optical conductivity and the real part of dielectric function are calculated by Kramers-Kronig(KK) relations. $\sigma_1(\omega)$ and $\epsilon_1(\omega)$ derivate from simple Drude model in low frequency range and tendencies of the three sample are different and non-monotonic. The Localization Modified Drude model(LMD) in the framework of Anderson-Mott theory can not give a good fit to the experimental data. By introducing a distribution of relaxation time into LMD, reasonable fits for all three samples are obtained. This result supports the inhomogeneous picture.Comment: 6 figures, 7 page