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Around 3-6% of children are affected by a specific reading disorder with neurobiological origin, or developmental dyslexia. People with dyslexia often exhibits negative emotional manifestation, such as anxiety. Findings of anxiety symptoms in dyslexia come primarily from self- and proxy reports. However some studies analyzed the autonomic activation of children with general learning disabilities, finding proofs of activation of the behavioural inhibition system, that could product withdrawal or anxiety. Main aim of this study is to investigate psychophysiological manifestations in connection to specific tasks, in children with dyslexia and in a control group of typical readers. Heart rate and Galvanic skin response (GSR), recorded during four tasks involving aloud and silent reading and vignettes description, were compared for children with dyslexia (n = 16) and a control group of typical readers (n = 16). Furthermore, children’s school wellness was measured through self and parent proxy-reports. Significantly lower GSR was found for dyslexic children in the reading aloud task, compared to the control group. Considering the dyslexic group, the discrepancy in the GSR between reading aloud and silently resulted significantly larger compared to the discrepancy between aloud and silent production in the vignettes description task. GSR registered during reading tasks correlated with Child’s emotional difficulties’ as reported by parents. No significant differences between groups nor correlations with questionnaires’ scores were found for heart rate recordings. Possible interpretations of the lower activation during reading aloud in dyslexic children are discussed.

Around 3-6% of children are affected by a specific reading disorder with neurobiological origin, or developmental dyslexia. People with dyslexia often exhibits negative emotional manifestation, such as anxiety. Findings of anxiety symptoms in dyslexia come primarily from self- and proxy reports. However some studies analyzed the autonomic activation of children with general learning disabilities, finding proofs of activation of the behavioural inhibition system, that could product withdrawal or anxiety. Main aim of this study is to investigate psychophysiological manifestations in connection to specific tasks, in children with dyslexia and in a control group of typical readers. Heart rate and Galvanic skin response (GSR), recorded during four tasks involving aloud and silent reading and vignettes description, were compared for children with dyslexia (n = 16) and a control group of typical readers (n = 16). Furthermore, children’s school wellness was measured through self and parent proxy-reports. Significantly lower GSR was found for dyslexic children in the reading aloud task, compared to the control group. Considering the dyslexic group, the discrepancy in the GSR between reading aloud and silently resulted significantly larger compared to the discrepancy between aloud and silent production in the vignettes description task. GSR registered during reading tasks correlated with Child’s emotional difficulties’ as reported by parents. No significant differences between groups nor correlations with questionnaires’ scores were found for heart rate recordings. Possible interpretations of the lower activation during reading aloud in dyslexic children are discussed.

Variations in heart rate variability (HRV) have been associated with major depressive disorder (MDD), but the relationship of baseline HRV to treatment outcome in MDD is unclear. We conducted a pilot study to examine associations between resting baseline HRV and MDD treatment outcome. We retrospectively tested several parameters of HRV in an MDD treatment study with escitalopram (ESC, N=26) to generate a model of how baseline HRV related to treatment outcome, and cross-validated the model in a separate trial of MDD treatment with Iyengar yoga (IY, N=16). Lower relative power of very low frequency (rVLF) HRV at baseline predicted improvement in depressive symptoms when adjusted for age and gender (R2>.43 and p

The photoabsorption spectra of neon and argon in the energy region of the 1s2p(5)nln'l' and 2p(5)3p(5)nln'l' doubly excited states have been studied. The resolution and flux of the new VUV undulator beam line at ELETTRA allowed the resolution of new features for Ne and the first observation for Ar. A comparison of the measured photoabsorption spectra and of the threshold photoelectron spectra in the energy region of the Ne+ 1s2p(5)nl and Ar+ 2p(5)3p(5)nl satellite states provides information on the decay routes of the inner-shell doubly excited states.

High resolution resonant Auger spectra have been measured at the VUV beam line at ELETTRA, Sincrotrone Trieste, while tuning the photon energy across the 2p(3/2)(-1)3d resonance of argon. A large variation of the branching ratio for decay into the spectator 3p(-2)3d and shakeup 3p(-2)4d channels is observed. The effect has not been seen previously in resonant inner-shell excitation and is attributed to the interference between the direct photoionization process and resonant Auger decay leading to the same final state.

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A Pb/Si(100)2x1 surface has been studied at T=120K by high resolution core-level spectroscopy using a third generation synchrotron light source. A strong component (S), could be identified at a binding energy (BE) of -0.20 ± 0.01 eV with respect to the bulk peak. This is indicative of some reorganization of the topmost silicon atoms after Pb adsorption with the formation of Si–Pb bonds and Pb–Pb symmetric dimers. However, this shift is in the opposite site respect to the bulk peak, as compared with Sb/Si(100)2x1, thus suggesting the interplay of final states screening effects and charge transfer in the core-level position. Another component (smaller than S) is present at +0.15 eV BE, and might be due to contribution from subsurface silicon atoms, as on the clean surface, and/or to surface or interface defects. On the Si 2p core-level taken in bulk sensitive mode, we found a very narrow bulk component with a total full width half maximum (FWHM) of 160 meV at T=120K indicative of an unreacted Si–Pb interface on top of an ideal Si bulk termination. The Pb 5d core-level spectrum is well represented by one doublet, thus suggesting that each Pb atom is adsorbed in a unique environment, i.e., there is no multisite adsorption.

Our photoemission spectroscopy results clearly demonstrate that symmetry breakdown in atomic arrangement brings about a lift of degeneracy in electronic states, leading to settle a long-standing controversy on a surface superstructure. We provide unambiguous evidences that Si(111)sqrt3xsqrt3-Ag has the inequivalent triangle structure (IET), excluding a long-lived honeycomb-chained triangle model. We also give critical experimental proof that the surface exhibits a disorder-order phase transition by cooling; the thermally fluctuating IET structure is frozen.

We investigate the evolution of the electronic structure across the insulator-metal transition in NiS2-xSex with changing composition, but in the absence of any structural or magnetic changes. A comparison of the inverse photoemission spectra with band-structure calculations establishes the importance of correlation effects in these systems. Systematic changes in the spectral distribution establish the persistence of the upper Hubbard band well into the metallic regime, with the insulator-to-metal transition being driven by a transfer of spectral weight from the Hubbard band to states close to the Fermi energy.

We report here on the electronic properties of the Ge/Sb/Si(001) interface formation studied by very high-energy-resolution photoemission spectroscopy using synchrotron radiation. Surface- and bulk-sensitive measurements of the core levels of the different atomic species give a clear indication of the occurrence of a site exchange process between germanium and antimony, when Ge is deposited on the already prepared Sb/Si(001) interface. We demonstrate that the use of surfactant atoms like Sb at the strained Ge/Si(001) interface produces a perfect epitaxial interface, where the Si atoms are in register with the bulk geometrical positions. © Società Italiana di Fisica.

The earliest stages of the oxygen interaction with clean and K-covered Si(100) surfaces (Theta(K) less than or equal to 0.5 ML) have been investigated using high-resolution core-level photoemission. The sequence of oxidation has been analyzed monitoring the different components of the Si 2p core level. In the case of the clean surface, the contribution coming from the upper dimer atoms is unaffected at the earliest stages of the oxidation. On the contrary, in the presence of It atoms, oxygen reacts rapidly with this type of silicon atoms, and the component is fully depleted after oxygen adsorption. The presence of I; atoms induces also the formation of a new oxide component in the Si 2p core level. Its small binding energy shift supports that a fraction of oxygen atoms are bonded at sites modified by the presence of K, forming a K-Si-O complex.

We performed a photoemission study on the (a-Si)/Si(111) homojunction with a thin intralayer of calcium fluoride (one monolayer). The intralayer and the amorphous silicon were grown in situ on cleaved Si(111) single crystals. From the core-level analysis we found a valence-band discontinuity of 0.35 eV due to the electrostatic dipole induced by the intralayer ionic bonds. Our results show that the intralayer forms an abrupt interface with Si and that the overlayer valence band has a lower binding energy than the substrate one. This implies that the most probable interface configuration is Si(111)-Ca-F(a-Si), confirming the results of previous works on the CaF2/Si(111) interface.