A proposed structural model for amyloid fibril elongation: domain swapping forms an interdigitating {beta}-structure polymer

We propose a model illustrating how proteins, which differ intheir overall sequences and structures, can form the propagating,twisted ß-sheet conformations, characteristic of amyloids.Some cases of amyloid formation can be explained through a `domainswapping' event, where the swapped segment is either a ß-hairpinor an unstable conformation which can partially unfold and assumea ß-hairpin structure. As in domain swapping, herethe swapped ß-hairpin is at the edge of the structure,has few (if any) salt bridges and hydrogen bonds connectingit to the remainder of the structure and variable extents ofburied non-polar surface areas. Additionally, in both casesthe swapped piece constitutes a transient `building block' ofthe structure, with a high population time. Whereas in domainswapping the swapped fragment has been shown to be an     

Effect of nanocellulose fibers and acetylated nanocellulose fibers on properties of poly(ethylene‐co‐vinyl acetate) foams

Cellulose nanofibers are promising materials in the development of polymeric foams, because they act as heterogeneous nucleation sites for the growth of cells during foaming. In this research, we studied the incorporation of cellulose nanoparticles in poly(ethylene‐co‐vinyl acetate)‐EVA foams. The foams were produced with different fiber contents. We observed the effect of a chemical treatment by acetylation on the cellulose fibber, that is, we evaluated the use of hydrophilic and hydrophobic cellulose nanofibers in EVA foams. The main results indicate that with the addition of only 1% of cellulose nanofibers, cell density significantly reduces when compared with the pure EVA foams. On the other hand, by increasing the cellulose content, the agglomeration of nanofibers also increases, which results in heterogeneous cell sizes. The same phenomenon was observed in the foams produced with acetylated cellulose nanofibers, regardless of the fiber content used. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44760.     

Enhancement of the Performance of Low-Efficiency HVAC Filters Due to Continuous Unipolar Ion Emission

Our novel concept utilizing continuous emission of unipolar ions, which has been recently proven to enhance the efficiency of facepiece respirators, was applied to conventional HVAC filters. Laboratory study demonstrated that the air ion emission in the vicinity of a low-efficiency HVAC filter significantly improves its performance. For example, the collection efficiency of two commercial HVAC filters challenged with 1μm PSL particles jumped from 5–15% (measured with no ion emission) to 40–90% (when the ion output rate was ～ 10¹² e^?/sec). The enhancement effect depends on the filter type and, generally, on the distance from the ion emitter to the filter surface. The results were explained as follows. The air ions with high mobility are deposited on the fibers forming a macroscopic electric field, which shield out some incoming unipolarly charged particles due to repelling forces. The field estimate has shown that this explanation is feasible. The enhancement effect seems to have a good potential to be employed in industrial and residential ventilation systems as it enhances the aerosol collection efficiency of a low-efficiency HVAC filter while not affecting its pressure drop.     

Polyglycolide‐based blends for drug delivery: A differential scanning calorimetry study of the melting behavior

The melting behavior of polyglycolide (PGA) with eight other biodegradable polymers was investigated to determine whether forming a blend could be used as a method of lowering the melting point of PGA. Blends were prepared by melt processing in differential scanning calorimetry (DSC) pans and were then analyzed by DSC. In every case, a comparison of the blend DSC plot with those of the two individual components showed that the melting behavior of PGA remained unchanged by blending. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2937–2939, 2003     

Tracking Protein S‐Fatty Acylation with Proteomics

Recently, Hang and co‐workers developed “acyl‐PEG exchange” (APE), which allows the investigation of protein S‐fatty acylation with mass‐tag labelling and gel electrophoresis, methods that are accessible to any biochemistry laboratory.     

Synthesis and characterisation of macroporous Yttria Stabilised Zirconia (YSZ) using polystyrene spheres as templates

Yttria Stabilised Zirconia (YSZ) is commonly used as an oxygen sensor and an oxygen pump in automotive and industrial applications, and is a choice electrolyte for Solid Oxide Fuel Cell (SOFC) technology. YSZ is also a major component of the SOFC electrodes, and is commonly mixed with 50% volume NiO to create a Ni/YSZ cermet anode. In both the adsorption and fuel cell applications homogeneous control of the porosity of YZS is important. Templating methods provide well ordered macroporous structures and have been used to prepare ordered, macroporous YSZ from metal nitrate precursors using polystyrene spheres of 1 μm as templates. Ordered three-dimensional structures were synthesised and the effects of sintering temperatures of 650–1400 °C on pore size, particle size and pore wall thickness were examined. Ordered porosity was maintained at all temperatures, though some structural degradation and sintering was observed at 1400 °C. This study demonstrated that templated porosity is maintained well above the conventional sintering temperature of the electrodes, and higher than previous studies reported. The stability of these structures at high temperatures makes this fabrication technique a promising alternative to conventional methods of synthesising porous materials.     

Functional Coupling of Slack Channels and P2X3 Receptors Contributes to Neuropathic Pain Processing

The sodium-activated potassium channel Slack (K_Na1.1, Slo2.2, or Kcnt1) is highly expressed in populations of sensory neurons, where it mediates the sodium-activated potassium current (I_KNa) and modulates neuronal activity. Previous studies suggest that Slack is involved in the processing of neuropathic pain. However, mechanisms underlying the regulation of Slack activity in this context are poorly understood. Using whole-cell patch-clamp recordings we found that Slack-mediated I_KNa in sensory neurons of mice is reduced after peripheral nerve injury, thereby contributing to neuropathic pain hypersensitivity. Interestingly, Slack is closely associated with ATP-sensitive P2X3 receptors in a population of sensory neurons. In vitro experiments revealed that Slack-mediated I_KNa may be bidirectionally modulated in response to P2X3 activation. Moreover, mice lacking Slack show altered nocifensive responses to P2X3 stimulation. Our study identifies P2X3/Slack signaling as a mechanism contributing to hypersensitivity after peripheral nerve injury and proposes a potential novel strategy for treatment of neuropathic pain.     

Fragment-Based Drug Discovery for RNA Targets

Rapid development within the fields of both fragment-based drug discovery (FBDD) and medicinal targeting of RNA provides possibilities for combining technologies and methods in novel ways. This review provides an overview of fragment-based screening (FBS) against RNA targets, including a discussion of the most recently used screening and hit validation methods such as NMR spectroscopy, X-ray crystallography, and virtual screening methods. A discussion of fragment library design based on research from small-molecule RNA binders provides an overview on both the currently limited guidelines within RNA-targeting fragment library design, and future possibilities. Finally, future perspectives are provided on screening and hit validation methods not yet used in combination with both fragment screening and RNA targets.     

Microwave hybrid fast sintering of red clay ceramics

This work aimed to examine the performance of the hybrid sintering of clay ceramic in a microwave furnace, compared to the sintering process in a conventional furnace. The raw materials were subjected to X-ray fluorescence, loss on ignition (LOI), X-ray diffraction, particle size distribution, real specific mass, and thermogravimetric analyses. The red clay ceramic mass was prepared, extruded, pre-sintered in a conventional furnace at 600°C/60 min, and sintered at temperatures between 700 °C and 1100 °C. The sintering conventional (resistive oven) was carried out for 60 min with a heating rate of 10°C/min. In the microwave furnace, the sintering times were 5, 10, and 15 min, with a heating rate of 50°C/min, with a sintering chamber coated with silicon carbide (susceptor). The sintered specimens were characterized according to linear shrinkage, water absorption, apparent porosity, apparent specific mass, X-ray diffraction, Raman spectroscopy analysis, spectroscopy analysis in the ultraviolet and visible regions, microhardness, and scanning electron microscopy. The results showed that microwave sintering promoted an increase in the microhardness and apparent specific mass, and reduction in water absorption and apparent porosity values, due to greater densification in the microstructure. The best results occurred for specimens sintered at 1100°C.