All-cellulose composites prepared from flax and lyocell fibres compared to epoxy–matrix composites

All-cellulose composites (ACCs) were prepared by partial dissolution in ionic liquid and compared to composites with epoxy matrix. Wide-angle X-ray diffraction and scanning electron microscopy were used to reveal differences in the structure of the composites. In tensile tests, lyocell-fibre based ACCs showed similar strength and stiffness, yet superior extensibility compared to lyocell-epoxy composites. However, when flax fibres were used, tensile properties clearly inferior to flax-epoxy were observed. Dynamic-mechanical and thermogravimetric analysis revealed a favourable behaviour for ACC in terms of more diffuse thermal softening and increased resistance to thermal degradation.     

Immunomodulatory efficiency of poly(2-oxazolines)

Poly(2-oxazolines) represent promising polymer materials for biomedical applications. The activation of mouse lymphoid macrophage line P388.D1 (clone 3124) by two selected representatives of poly(2-oxazolines), namely poly(2-ethyl-2-oxazoline) (PETOX100) and poly[2-(4-aminophenyl)-2-oxazoline-co-2-ethyl-2-oxazoline] (AEOX10), was assessed in vitro. The immunomodulatory efficacy of both polymers was evaluated via the induced release of pro-inflammatory cytokines (TNF-α, IL-1α and IL-6) and the acceleration of reactive free radicals. The present study revealed effective structure-immunomodulating associations of AEOX10 and PETOX100, which are desirable in biomedical and pharmaceutical applications of aliphatic and aromatic poly (2-oxazolines) in vivo.     

Quality perception,purchase intention,and the impact of information on the evaluation of refined Pacific cupped oysters (Crassostrea gigas) by Dutch consumers

BACKGROUND

Oyster refinement using land‐based pond systems is a new activity in the Dutch oyster sector. It increases the oyster's tissue weight and changes its sensorial properties. However, the response of Dutch consumers towards refined oysters is unknown. The research aim was to gain insight into the importance of oyster quality parameters, drivers for oyster consumption, and acceptance of refined oysters by Dutch consumers, taking into account the information given to them about the product and process.

RESULTS

Taste, texture, and odor are the most important oyster quality characteristics for Dutch consumers. The outcome of questionnaires showed that willingness to buy and pay is influenced by factors such as the oysters' country of origin, cultivation area, and flavor profile. Refinement did not affect willingness to buy and pay. Furthermore Dutch consumers seem to have a preference for the flavor profile of refined oysters. Consumer evaluation showed that refined Pacific cupped oysters were perceived as sweeter compared with non‐refined oysters. When information on the cultivation process was disclosed, overall appreciation of refined oysters by consumers increased.

CONCLUSION

New insights in the importance of oyster quality characteristics for Dutch consumers are generated that can be used in the development of refined Pacific cupped oysters. © 2018 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

MULSOPS: Multivariate Optimized Pit Shells Simulator for tactical mine planning

Abstract

Production planning, scheduling and allocation of resources in large-scale surface mining operations present a great challenge to mine planning engineers. Ore and waste extraction plans must be executed to achieve tactical objectives using appropriate tools. Many production planning and scheduling and resource allocation methods are based on trial and error, crisis management or subjective judgements with no detailed economic basis or mathematical rigour. In addition, these methods do not consider the random processes governing critical development and production variables. In this study, the authors develop a multivariate pit shell simulator, MULSOPS, which addresses these problems. Rigorous geometric formulations of the ellipsoidal approximations of the pit shells geometry, their expansions and sequential interactions are modeled to mimic material displacement dynamics in an open pit operation. Stochastic and numerical modeling techniques are used to provide solutions to the time-dependent geometric models in random multivariate states Under different production and economic paradigms, the geometric models are simulated to yield the source and characteristics of appropriate cuts. Combined production from successive exposed cuts provides periodic targets for tactical planning. Variance simulation is also used to provide analysts with sensitive stochastic variables for input data definition and tight production target tolerance. A numerical example is used to illustrate the use of MULSOPS for tactical planning in a typical open pit operation.     

Measurement of intrinsic properties of amyloid fibrils by the peak force QNM method

We report the investigation of the mechanical properties of different types of amyloid fibrils by the peak force quantitative nanomechanical (PF-QNM) technique. We demonstrate that this technique correctly measures the Young's modulus independent of the polymorphic state and the cross-sectional structural details of the fibrils, and we show that values for amyloid fibrils assembled from heptapeptides, α-synuclein, Aβ(1-42), insulin, β-lactoglobulin, lysozyme, ovalbumin, Tau protein and bovine serum albumin all fall in the range of 2-4 GPa.     

Characterization of antibacterial polyethersulfone membranes using the respiration activity monitoring system (RAMOS)

Membranes with antibacterial properties were developed using surface modification of polyethersulfone ultrafiltration membranes. Three different modification strategies using polyelectrolyte layer-by-layer (LbL) technique are described. The first strategy relying on the intrinsic antibacterial properties of poly(diallyldimethylammonium chloride) (PDADMAC) and poly(ethylenimine) (PEI) exhibits only little antibacterial effects. The other two strategies contain silver in both ionic (Ag⁺) and metallic (Ag⁰) form. Ag⁺ embedded into negatively charged poly(sodium 4-styrene sulfonate) (PSS) layers totally inhibits bacterial growth. Ag⁰ nanoparticles were introduced to the membrane surface by LbL deposition of chitosan- and poly(methacrylic acid) - sodium salt (PMA)-capped silver nanoparticles and subsequent UV or heat treatment. Antibacterial properties of the modified membranes were quantified by a new method based on the Respiration Activity Monitoring System (RAMOS), whereby the oxygen transfer rates (OTR) of E. coli K12 cultures on the membranes were monitored online. As opposed to colony forming counting method RAMOS yields more quantitative and reliable data on the antibacterial effect of membrane modification. Ag-imprinted polyelectrolyte film composed of chitosan (Ag⁰)/PMA(Ag⁰)/chitosan(Ag⁰) was found to be the most promising among the tested membranes. Further investigation revealed that the concentration and equal distribution of silver in the membrane surface plays an important role in bacterial growth inhibition.     

Evaluation of effect of paddle element stagger angle on the local velocity profiles in a twin-screw continuous mixer with viscous flow using Finite Element Method simulations

The effect of paddle element geometry, specifically a systematic change in stagger angle, on the velocity distribution of a Newtonian corn syrup was evaluated in the mixing region of a 2″ Readco continuous processor using 3D FEM simulations. Local velocities and regions of backflow were compared for three configurations of the paddle elements in the mixing region consisting of nine pairs of paddle elements with the central three being in a neutral (FLAT), staggered 45° forward (45F) or staggered 45° reverse (45R) configuration. The total material flow rate through the mixer was independent of the paddle element stagger but increased with screw speed when the mixer was operated with the barrel fully filled. The stagger angle variation caused only local disturbances in axial flow. The overall magnitudes of velocity were highest for the FLAT configuration followed by 45F and 45R. The local X and Y velocity components in the region of stagger showed no significant variation with paddle element stagger while the Z velocity component varied significantly in this region. Increased forward flow was seen for the 45F configuration while significant local backflow was seen for the 45R configuration at all positions of the paddle element rotation. The FLAT configuration had greater levels of pressure in the intermeshing region, suggesting a squeeze flow while there were not significant variations in pressure for the 45F and 45R configurations, suggesting a predominantly conveying/leakage flow in the axial direction. Variation in local flows is critical to good mixing.     

Design procedure of simple and accurate model of electric double layer capacitor (EDLC) targeting fast verification purposes of heat transfer simulations

From the macrostructure of electric double layer capacitor (EDLC) and from heat transfer point of view, the volumetric properties of EDLC act as surrounding anisotropy. The core of the supercapacitor is made of coil, which is composed of a number of turns. This coil is from the physical aspect represented as a anisotropic structure that has to be considered during the design of a 3D model. Such structure of capacitor’s core is then in axial direction geometrically and physically different comparing to radial direction. This results in diverse expression of thermal conductivities in the mentioned directions. Therefore, it is necessary to analytically determine axial and radial parts of heat conduction thus avoiding high degree of thermal model’s complexity. After mathematical analysis, this paper will also describe the procedure of design of the EDLC thermal simulation model. During development of EDLC thermal model, and for computational and simulation purposes, the CFD software, COMSOL 3.5a, has been used. The principal aim was to reach very close proximity of the simulation results as compared to measurements, and simultaneously achieve very low computational time. Targeting high degree of model’s accuracy, several alternatives of model complexity will be shown.     

Protocadherin 19 Clustering Epilepsy and Neurosteroids: Opportunities for Intervention

Steroids yield great influence on neurological development through nuclear hormone receptor (NHR)-mediated gene regulation. We recently reported that cell adhesion molecule protocadherin 19 (encoded by the PCDH19 gene) is involved in the coregulation of steroid receptor activity on gene expression. PCDH19 variants cause early-onset developmental epileptic encephalopathy clustering epilepsy (CE), with altered steroidogenesis and NHR-related gene expression being identified in these individuals. The implication of hormonal pathways in CE pathogenesis has led to the investigation of various steroid-based antiepileptic drugs in the treatment of this disorder, with mixed results so far. Therefore, there are many unmet challenges in assessing the antiseizure targets and efficiency of steroid-based therapeutics for CE. We review and assess the evidence for and against the implication of neurosteroids in the pathogenesis of CE and in view of their possible clinical benefit.