P01-190 Predictors of mania in a sample of patients treated with antidepressants (preliminary results)

Aims:From 35% to 60% of cases the initial presentation of illness in bipolar disorder is different from mania or hypomania. So far the studies that have investigated predictors of (hypo)mania have been concentrated on samples suffering from depression. On one hand is well known that antidepressant drugs are commonly prescribed in a broad spectrum of disorders other than depression. On the other hand there are strong connections within bipolar disorder and anxiety disorders that have been reported to be a possible clinical onset of a subsequent bipolar disorder.In all these cases patients are likely to be treated with antidepressants drugs, the effects of which has been associated with a worsened course of bipolar illness, from switching to mania to a rapid cycling course. This is the reason that led to perform a research on predictors of bipolar evolution on an antidepressant treated sample of outpatients irrespective of the diagnosis.This study examines clinical features at the first presentation of the illness that can be considered predictive of the subsequent bipolar course of illness.Method:A sample of outpatients treated for the first time in their life with antidepressant drugs has been prospectively evaluated in order to assess the clinical features associated with the later onset of bipolar disorder

Theory of scanning gate microscopy

A systematic theory of the conductance measurements of non-invasive (weak probe) scanning gate microscopy is presented that provides an interpretation of what precisely is being measured. A scattering approach is used to derive explicit expressions for the first and second order conductance changes due to the perturbation by the tip potential in terms of the scattering states of the unperturbed structure. In the case of a quantum point contact, the first order correction dominates at the conductance steps and vanishes on the plateaus where the second order term dominates. Both corrections are non-local for a generic structure. Only in special cases, such as that of a centrally symmetric quantum point contact in the conductance quantization regime, can the second order correction be unambiguously related with the local current density. In the case of an abrupt quantum point contact we are able to obtain analytic expressions for the scattering eigenfunctions and thus evaluate the resulting conductance corrections.Comment: 19 pages, 7 figure

KLOE results at the Frascati ϕ\phi-factory DAΦ\PhiNE

The KLOE experiment at the Frascati $\phi$-factory DA$\Phi$NE has collected about 0.5 fb$^{-1}$ of data till the end of the year 2002. These data allow to perform a wide physics program, ranging from the physics of charged and neutral kaons to radiative $\phi$-decays. Results are presented for the $K_L$ lifetime and the semileptonic processes $K_{S,L} \to \pi e \nu$. From the light meson spectroscopy program, results on the decays $\phi \to f_0(980)\gamma, a_0(980)\gamma$ as well as $\phi \to \eta \gamma, \eta' \gamma$ are presented.Comment: 5 pages, 3 figures, Proceedings contribution to the 10th Int. Symposium on "Meson-Nucleon Physics and the Structure of the Nucleon" (MENU04), Beijing, China, Aug. 30 - Sept. 4, 200

Facility for fast neutron irradiation tests of electronics at the ISIS spallation neutron source

The VESUVIO beam line at the ISIS spallation neutron source was set up for neutron irradiation tests in the neutron energy range above 10 MeV. The neutron flux and energy spectrum were shown, in benchmark activation measurements, to provide a neutron spectrum similar to the ambient one at sea level, but with an enhancement in intensity of a factor of 107. Such conditions are suitable for accelerated testing of electronic components, as was demonstrated here by measurements of soft error rates in recent technology field programable gate arrays

Spacetime geometries and light trapping in travelling refractive index perturbations

In the framework of transformation optics, we show that the propagation of a locally superluminal refractive index perturbation (RIP) in a Kerr medium can be described, in the eikonal approximation, by means of a stationary metric, which we prove to be of Gordon type. Under suitable hypotheses on the RIP, we obtain a stationary but not static metric, which is characterized by an ergosphere and by a peculiar behaviour of the geodesics, which are studied numerically, also accounting for material dispersion. Finally, the equation to be satisfied by an event horizon is also displayed and briefly discussed.Comment: 14 pages, 7 figure

Analogue Gravity and ultrashort laser pulse filamentation

Ultrashort laser pulse filaments in dispersive nonlinear Kerr media induce a moving refractive index perturbation which modifies the space-time geometry as seen by co-propagating light rays. We study the analogue geometry induced by the filament and show that one of the most evident features of filamentation, namely conical emission, may be precisely reconstructed from the geodesics. We highlight the existence of favorable conditions for the study of analogue black hole kinematics and Hawking type radiation.Comment: 4 pages, revised versio

Effect of ageing and ischemia on enzymatic activities linked to Krebs' cycle, electron transfer chain, glutamate and aminoacids metabolism of free and intrasynaptic mitochondria of cerebral cortex

The effect of ageing and the relationships between the catalytic properties of enzymes linked to Krebs' cycle, electron transfer chain, glutamate and aminoacid metabolism of cerebral cortex, a functional area very sensitive to both age and ischemia, were studied on mitochondria of adult and aged rats, after complete ischemia of 15 minutes duration. The maximum rate (V (max)) of the following enzyme activities: citrate synthase, malate dehydrogenase, succinate dehydrogenase for Krebs' cycle; NADH-cytochrome c reductase as total (integrated activity of Complex I-III), rotenone sensitive (Complex I) and cytochrome oxidase (Complex IV) for electron transfer chain; glutamate dehydrogenase, glutamate-oxaloacetate- and glutamate-pyruvate transaminases for glutamate metabolism were assayed in non-synaptic, perikaryal mitochondria and in two populations of intra-synaptic mitochondria, i.e., the light and heavy mitochondrial fraction. The results indicate that in normal, steady-state cerebral cortex, the value of the same enzyme activity markedly differs according (a) to the different populations of mitochondria, i.e., non-synaptic or intra-synaptic light and heavy, (b) and respect to ageing. After 15 min of complete ischemia, the enzyme activities of mitochondria located near the nucleus (perikaryal mitochondria) and in synaptic structures (intra-synaptic mitochondria) of the cerebral tissue were substantially modified by ischemia. Non-synaptic mitochondria seem to be more affected by ischemia in adult and particularly in aged animals than the intra-synaptic light and heavy mitochondria. The observed modifications in enzyme activities reflect the metabolic state of the tissue at each specific experimental condition, as shown by comparative evaluation with respect to the content of energy-linked metabolites and substrates. The derangements in enzyme activities due to ischemia is greater in aged than in adult animals and especially the non-synaptic and the intra-synaptic light mitochondria seems to be more affected in aged animals. These data allow the hypothesis that the observed modifications of catalytic activities in non-synaptic and intra-synaptic mitochondrial enzyme systems linked to energy metabolism, amino acids and glutamate metabolism are primary responsible for the physiopathological responses of cerebral tissue to complete cerebral ischemia for 15 min duration during agein

Gravity of a static massless scalar field and a limiting Schwarzschild-like geometry

We study a set of static solutions of the Einstein equations in presence of a massless scalar field and establish their connection to the Kantowski-Sachs cosmological solutions based on some kind of duality transformations. The physical properties of the limiting case of an empty hyperbolic spacetime (pseudo-Schwarzschild geometry) are analyzed in some detail.Comment: 13 pages, 4 figure

Reply to Comment on: Hawking radiation from ultrashort laser pulse filaments

A comment by R. Schutzhold et al. raises possible concerns and questions regarding recent measurements of analogue Hawking radiation. We briefly reply to the opinions expressed in the comment and sustain that the origin of the radiation may be understood in terms of Hawking emission