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Neural activity during early development is known to alter innervation pathways in the central and peripheral nervous systems. We sought to examine how reduced sound-induced sensory activity in the cochlea affected the consolidation of glutamatergic synapses between inner hair cells (IHC) and the primary auditory neurons as these synapses play a primary role in transmitting sound information to the brain. A unilateral conductive hearing loss was induced prior to the onset of sound-mediated stimulation of the sensory hair cells, by rupturing the tympanic membrane and dislocating the auditory ossicles in the left ear of P11 mice. Auditory brainstem responses at P15 and P21 showed a 40–50-dB increase in thresholds for frequencies 8–32 kHz in the dislocated ear relative to the control ear. Immunohistochemistry and confocal microscopy were subsequently used to examine the effect of this attenuation of sound stimulation on the expression of RIBEYE, which comprises the presynaptic ribbons, Shank-1, a postsynaptic scaffolding protein, and the GluA2/3 and 4 subunits of postsynaptic AMPA receptors. Our results show that dislocation did not alter the number of pre- or postsynaptic protein puncta. However, dislocation did increase the size of RIBEYE, GluA4, GluA2/3 and Shank-1 puncta, with postsynaptic changes preceding presynaptic changes. Our data suggest that a reduction in sound stimulation during auditory development induces plasticity in the molecular make-up of IHC glutamatergic synapses, but does not affect the number of these synapses. Up-regulation of synaptic proteins with sound attenuation may facilitate a compensatory increase in synaptic transmission due to the reduced sensory stimulation of the IHC. [ABSTRACT FROM AUTHOR]

Hemp–lime is a potentially useful building material with relatively low embodied energy and moderate-to-good thermal performance, coupled with good moisture buffering capacity. However, some uncertainty remains with regards to its in-situ thermal performance and the capability of building energy simulation tools to accurately predict envelope performance and subsequent energy demand of buildings constructed of such vapour-active materials. In this paper we investigate the hygrothermal performance of buildings with walls constructed from hemp–lime. Component-level moisture buffering simulation employing the EnergyPlus simulation tool is found to be within 18% of Wufi Pro analysis and laboratory measurements. The coarseness of component discretization is shown to effect moisture buffering leading to the observation that finer discretization should be employed to improve EnergyPlus HAMT model accuracy. Whole building simulation of the BESTEST building with hemp–lime components indicates that moisture transport inclusion has a large influence on zone relative humidity but little influence on overall heating and cooling demand. A simple effective-capacitance model is able to represent humidity buffering but is less good at representing the response to sudden moisture loading. An additional resistance parameter is added to the model and an IES-ve simulation using this approach is shown to give a close match to the full hygric simulation. [ABSTRACT FROM AUTHOR]

Metallic glasses have received attention in the world of materials science and engineering due to their high mechanical and tribological properties. Thin film nanostructured metallic glasses have shown great prospects as surface coatings with increasing applications in biomedical areas for implants and surgical devices. In this work, we deposited titanium- and zirconium-based polymorphous thin film metallic glasses (Ti–Fe–Cu, Zr–Fe–Al, Zr–W–Cu) on medical-grade polished titanium substrate by co-sputtering using a PVD system. The corrosion behaviour of the films was investigated by exposing the samples to sterile simulated body fluid and examined using electrochemistry, microscopy, and spectroscopic analyses. The polymorphic properties of the films after exposure to simulated body fluid were observed by SEM and TEM. SEM analysis shows that the surface morphology of the exposed samples was found to vary significantly compared to their corresponding as-deposited samples. Electrochemical properties (E corr , I corr , and OCV, impedance |Z|) demonstrated that the thin film metallic glasses were found to enhance the corrosion resistance of the substrate. Further investigations of the exposed films by XPS and Raman analyses have revealed that the induced oxide passive layer significantly enhanced the corrosion efficacy of the films on titanium substrate. Among the three samples, Zr–W–Cu coating has shown the highest corrosion protection almost 450 times better than the bare titanium substrate. [Display omitted] • Polymorphous thin film metallic glass mitigates corrosion by formation of oxide layers. • Polymorphous thin film metallic glass coating offers protection from corrosion in the body environment for Ti substrates. • Zr-based (ZrWCu) nanostructured polymorphous thin film metallic glass significantly deters biocorrosion on Ti substrates. [ABSTRACT FROM AUTHOR]