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Aims: to assess occurrence and clinical correlates of neurogenic heterotopic ossifications (NHO) in patients with prolonged disorder of consciousness (DoC). Design: multi-center cross-sectional observational study. Setting: 23 intensive neurorehabilitation units. Subjects: 287 patients with prolonged disorder of consciousness (DoC; 150 in vegetative state, VS, and 128 in minimally conscious state, MCS) of different etiology (vascular = 125, traumatic = 83, anoxic = 56, others = 14). Main Measures: clinical evidence of NHO confirmed by standard radiological and/or sonographic evaluation; Coma Recovery Scale-Revised; Disability Rating Scale (DRS); Early Rehabilitation Barthel Index; presence of ventilator support, spasticity, bone fractures and paroxysmal sympathetic hyperactivity. Results: 31 patients (11.2%) presented NHO. Univariate analyses showed that NHO was associated with VS diagnosis, traumatic etiology, high DRS category and total score, and high occurrence of limb spasticity and bone fractures. A cluster-corrected binary logistic regression model (excluding spasticity available in a subset of patients) showed that only lower DRS total score and presence of bone fractures were independently associated with NHO. Conclusions: NHO are relatively frequent in patients with DoC, and are independently associated with functional disability, bone fractures and spasticity. These findings contribute to identifying patients with DoC prone to develop NHO and requiring special interventions to improve functional recovery. [ABSTRACT FROM AUTHOR]

Aim: to assess overall clinical complexity of patients with acquired disorders of consciousness (DoC) in vegetative state/unresponsive wakefulness syndrome (VS/UWS) vs. minimally conscious state- MCS) and in different etiologies.. Design: Multi-center cross-sectional observational study. Setting: 23 intensive neurorehabilitation units. Subjects: 264 patients with DoC in the post-acute phase: VS/UWS = 141, and MCS = 123 due to vascular (n = 125), traumatic (n = 83) or anoxic (n = 56) brain injury. Main Measures: Coma Recovery Scale-Revised, and Disability Rating Scale (DRS); presence of medical devices (e.g., for eating or breathing); occurrence and severity of medical complications. Results: patients in DoC, and particularly those in VS/UWS, showed severe overall clinical complexity. Anoxic patients had higher overall clinical complexity, lower level of responsiveness/consciousness, higher functional disability, and higher needs of medical devices. Vascular patients had worse premorbid clinical comorbidities. The two etiologies showed a comparable rate of MC, higher than that observed in traumatic etiology. Conclusion: overall clinical complexity is significantly higher in VS/UWS than in MCS, and in non-traumatic vs. traumatic etiology. These findings could explain the worse clinical evolution reported in anoxic and vascular etiologies and in VS/UWS patients and contribute to plan patient-tailored care and rehabilitation programmes. [ABSTRACT FROM AUTHOR]

We report a detailed analysis of the dynamic structure factor of glassy sorbitol by using inelastic X-ray scattering and previously measured light scattering data [B. Ruta, G. Monaco, F. Scarponi, and D. Fioretto, Philos. Mag. 88, 3939 (2008)]. The thus obtained knowledge on the density-density fluctuations at both the mesoscopic and macroscopic length scale has been used to address two debated topics concerning the vibrational properties of glasses. The relation between the acoustic modes and the universal boson peak (BP) appearing in the vibrational density of states of glasses has been investigated, also in relation with some recent theoretical models. Moreover, the connection between the elastic properties of glasses and the slowing down of the structural relaxation process in supercooled liquids has been scrutinized. For what concerns the first issue, it is here shown that the wave vector dependence of the acoustic excitations can be used, in sorbitol, to quantitatively reproduce the shape of the boson peak, supporting the relation between BP and acoustic modes. For what concerns the second issue, a proper study of elasticity over a wide spatial range is shown to be fundamental in order to investigate the relation between elastic properties and the slowing down of the dynamics in the corresponding supercooled liquid phase. [ABSTRACT FROM AUTHOR]

The longitudinal viscosity of diluted water-tert-butyl alcohol solutions in the 10 GHz frequency region has been measured by means of Brillouin light scattering and inelastic ultraviolet scattering. The main advantage of our hypersonic investigation compared to more traditional ultrasonic measurements is that in the gigahertz frequency range slow relaxation processes involving the alcohol dynamics are completely unrelaxed, so that the measured viscosity mainly originates from the hydrogen bond restructuring of water. In contrast with previous determinations, we estimate an activation energy which is independent from the alcohol mole fraction up to X = 0.1, and comparable to that of bulk water. A simple two-component model is used to describe the steep increase of viscosity with increasing alcohol mole fraction, and a retardation factor 1.7 ± 0.2 is found between the relaxation times of hydration and bulk water. These findings endorse a dynamic scenario where the slowing down of hydration water is mainly due to a reduction of configurational entropy and does not involve an arrested, icelike, dynamics. [ABSTRACT FROM AUTHOR]

The results of a combined experimental study of the high-frequency acoustic dynamics and of the vibrational density of states (VDOS) as a function of temperature in a glass of sorbitol are reported here. The excess in the VDOS at ∼4.5 meV over the Debye, elastic continuum prediction (boson peak) is found to be clearly related to anomalies observed in the acoustic dispersion curve in the mesoscopic wavenumber range of few nm-1. The quasiharmonic temperature dependence of the acoustic dispersion curves offers a natural explanation for the observed scaling of the boson peak with the elastic medium properties. [ABSTRACT FROM AUTHOR]

We measured the dynamic structure factor of the liquid and glassy phases of the LiCl–6H2O solution by means of inelastic scattering of radiation in the visible, UV, and x-ray range, between 1 GHz and 10 THz, and by means of photon-correlation spectroscopy, between 0.01 Hz and 20 kHz. The measurements were performed in the temperature range between 353 and 80 K. Our data show that a single-relaxation process exists at high temperature, which has features similar to those of the single relaxation of pure water. Upon cooling the system below ∼220 K, this single mode starts to differentiate two processes, a structural (α-) and a secondary (β-) relaxation. As the temperature is decreased, the β-relaxation is the vanishing continuation of the single, high-temperature process, while the onset of the α-relaxation occurs at the expense of the β-process. [ABSTRACT FROM AUTHOR]

Brillouin light scattering has been used to investigate the density fluctuations of the fragile glass-former sorbitol in the GHz frequency range and at temperatures between 20 and 294 K. Longitudinal acoustic sound velocity and attenuation data are here reported and discussed. These data are used to test the existence of a correlation between elastic properties of glasses and viscous properties of the corresponding deeply undercooled melts above the glass transition temperature, Tg. In particular, and as for other fragile systems, the ratio of the vibrational to the relaxational compressibility at Tg is found to be basically independent of fragility. [ABSTRACT FROM AUTHOR]

The dynamics of density fluctuations of aqueous glucose solutions were studied in the water-rich region by means of Brillouin ultra-violet scattering. The temperature dependence of the position and line-width of inelastic peaks gives evidence of a strong relaxation process located in the picosecond timescale. In the approximation of a single exponential process, the relaxation time, τ, was obtained for different glucose concentrations; its temperature dependence is well described by an Arrhenius law characterized by an activation energy comparable to that of pure water. This result supports the hypothesis that the microscopic mechanism responsible for the main relaxation process in sugar-water solutions is the continuum rearrangement of the hydrogen-bond network. A comparison is also reported with previous results on aqueous trehalose solutions, showing the acoustic absorption scales with the number of glucoside units for both glucose and trehalose aqueous solutions. [ABSTRACT FROM AUTHOR]

The dynamics of liquid sulphur have been investigated in the temperature region corresponding to the so-called λ transition by means of Brillouin light scattering. Results of this work, together with ultrasonic spectroscopy and inelastic X-ray scattering results in literature, indicate that the main structural relaxation is slightly affected by the transition and suggest that the dramatic increase of shear viscosity is related to the onset of a low-frequency additional relaxation. Such a feature is commonly found in rubber-like materials and can be related to the polymerization of sulphur molecules across the transition. [ABSTRACT FROM AUTHOR]

Brillouin light and X-ray scattering have been used to investigate the dynamic structure factor of supercooled and glassy m-toluidine in the temperature range 34-303 K. In addition to the ubiquitous α-relaxation, evidence is given of a fast relaxation process active in the ns-ps time region. Data on activation energy of the fast process are obtained from the attenuation of longitudinal acoustic modes. [ABSTRACT FROM AUTHOR]

An array of multilayered rectangular NiFe/Cu/NiFe dots (lateral dimensions 720 × 430 nm, thicknesses 10/10/10 nm) has been fabricated by electron-beam lithography. The magnetization reversal process has been studied by the magneto-optical Kerr effect, showing that the dipolar coupling between the two magnetic layers plays an important role and competes with shape anisotropy, determining the characteristic profile of the hysteresis curve. Moreover, both conventional and microfocused Brillouin light scattering have been exploited to study the eigenmodes spectrum in the gigahertz range, achieving a direct visualization of the spatial profile of the different modes. The results are in good agreement with both the modes frequency and the spatial profiles obtained by micromagnetic simulations. [ABSTRACT FROM AUTHOR]

Purpose.To review on the application of the ICF Classification to assess the person with traumatic brain injury (TBI) and his/her interaction with the environment. Method.Studies and reviews about the use of ICF in TBI have been included, by searching in Pubmed and in the proceedings of international meetings. Results.Eleven studies have been identified and classified into three types: (a) application of the classification; (b) single case study; (c) the use of other scales. Some studies are related to the application of ICF checklist. Finally, we analyse the most used ICF codes. Conclusions.The ICF is a useful tool describes conditions and needs of patients with TBI. A diffuse utilisation could become the key resource for both health professionals and administrators that are in charge of allocating resources to pursue quality of life improvement. The ICF could be applied as a shared language to define health programmes' goals and as system for carrying out epidemiological studies. For this reason, it is desirable to define and validate the ICF Core Sets for TBI to provide a mean to be easily used, comprehensive and universal. [ABSTRACT FROM AUTHOR]