Anthropogenic microparticles in the emerald rockcod Trematomus bernacchii (Nototheniidae) from the Antarctic.

Anthropogenic microparticles (AMs) were found for the first time in specimens of Trematomus bernacchii collected in 1998 in the Ross Sea (Antarctica) and stored in the Antarctic Environmental Specimen Bank. Most of the identified AMs were fibers of natural and synthetic origin. The natural AMs were cellulosic, the synthetic ones were polyester, polypropylene, polypropylene/polyester, and cellulose acetate. The presence of dyes in the natural AMs indicates their anthropogenic origin. Five industrial dyes were identified by Raman spectroscopy with Indigo occurring in most of them (55%). Our research not only adds further data to the ongoing knowledge of pollution levels in the Antarctic ecosystem, it provides an interesting snapshot of the past, highlighting that microplastics and anthropogenic fiber pollution had already entered the Antarctic marine food web at the end of the '90 s. These findings therefore establish the foundations for understand the changes in marine litter pollution over time.

Multiple Interacting Collective Modes and Phonon Gap in Phospholipid Membranes.

We combine Brillouin neutron scattering measurements with recent inelastic X-ray scattering [ Zhernenkov et al. Nat. Commun. 2016 , 7 , 11575 ] to propose a model for the collective dynamics of phospholipid bilayers. Neutron and X-ray spectra were fitted by the model response function associated with the Hamiltonian of an interacting-phonon system. This approach allows for a comprehensive and unprecedented picture of the vibrational collective features of phospholipids. At low wavevectors Q, the dispersion relations can be interpreted in terms of two acoustic-like modes, one longitudinal and one transverse, plus a dispersionless optic-like mode. The transverse mode of the liquid phase shows a phonon gap that can be linked to a passive transport mechanism through membranes, an interpretation that was proposed in Zhernenkov et al. At higher Q values, the interaction of the longitudinal acoustic excitation with the dispersionless mode gives rise to a pattern that is consistent with avoided-crossing behavior. Evidence is found for a slow- to fast-sound transition, similar to bulk water and other biomolecules.

Is non-invasive neuromuscular electrical stimulation effective in severe chronic neurogenic dysphagia? Reporton a post-traumatic brain injury patient.

BACKGROUND: Neurogenic dysphagia is a difficulty in swallowing induced by nervous system disease. It often causes serious complications, which are preventable if dysphagia is properly managed. There is growing debate concerning the usefulness of non-invasive neuromuscular electrical stimulation (NMES) in treating swallowing dysfunction. OBJECTIVE: Aim of this study was to assess the effectiveness of Vitalstim© device, and to investigate the neurophysiological mechanisms underlying functional recovery. METHODS: A 34-year-old man, affected by severe chronic dysphagia following traumatic brain injury, underwent two different intensive rehabilitation trainings, including either conventional rehabilitation alone or coupled to Vitalstim training. We evaluated patient swallowing function in two separate sessions (i.e. before and after the two trainings) by means of ad hoc swallowing function scales and electrophysiological parameters (rapid paired associative stimulation). The overall Vitalstim program was articulated in 6 weekly sessions for 6 weeks. RESULTS: The patient did not report any side-effect either during or following both the intensive rehabilitation trainings. We observed an important improvement in swallowing function only after Vitalstim training. In fact, the patient was eventually able to safely eat even solid food. CONCLUSIONS: This is the first report objectively suggesting (by means of rPAS) a correlation between the brain neuroplastic changes induced by Vitalstim and the swallowing function improvement. It is hypothesizable that Vitalstim may have targeted cortical (and maybe subcortical) brain areas that are recruited during the highly coordinated function of swallowing, and it may have thus potentiated the well-known neuroplastic changes induced by repetitive and intensive swallowing exercises, probably thanks to metaplasticity phenomena.

Lipid diffusion in alcoholic environment.

We have studied the effects of a high concentration of butanol and octanol on the phase behavior and on the lateral mobility of 1,2-palmitoyl-sn-glycero-3-phosphocholine (DPPC) by means of differential scanning calorimetry and pulsed-gradient stimulated-echo (PGSTE) NMR spectroscopy. A lowering of the lipid transition from the gel to the liquid-crystalline state for the membrane-alcohol systems has been observed. NMR measurements reveal three distinct diffusions in the DPPC-alcohol systems, characterized by a high, intermediate, and slow diffusivity, ascribed to the water, the alcohol, and the lipid, respectively. The lipid diffusion process is promoted in the liquid phase while it is hindered in the interdigitated phase due to the presence of alcohols. Furthermore, in the interdigitated phase, lipid lateral diffusion coefficients show a slight temperature dependence. To the best of our knowledge, this is the first time that lateral diffusion coefficients on alcohol with so a long chain, and at low temperatures, are reported. By the Arrhenius plots of the temperature dependence of the diffusion coefficients, we have evaluated the apparent activation energy in both the liquid and in the interdigitated phase. The presence of alcohol increases this value in both phases. An explanation in terms of a free volume model that takes into account also for energy factors is proposed.

Ethanol enhances collective dynamics of lipid membranes.

From inelastic neutron-scattering experiments and all atom molecular dynamics simulations we present evidence for a low-energy dynamical mode in the fluid phase of a 1,2-dimyristoyl-sn-glycero-3-phoshatidylcholine (DMPC) bilayer immersed in a 5% water/ethanol solution. In addition to the well-known phonon that shows a liquidlike dispersion with energies up to 4.5 meV, we observe an additional mode at smaller energies of 0.8 meV, which shows little or no dispersion. Both modes show transverse properties and might be related to molecular motion perpendicular to the bilayer.