Rapid Processing of Net-Shape Thermoplastic Planar-Random Composite Preforms

A novel thermoplastic composite preforming and moulding process is investigated to target cost issues in textile composite processing associated with trim waste, and the limited mechanical properties of current bulk flow-moulding composites. The thermoplastic programmable powdered preforming process (TP-P4) uses commingled glass and polypropylene yarns, which are cut to length before air assisted deposition onto a vacuum screen, enabling local preform areal weight tailoring. The as-placed fibres are heat-set for improved handling before an optional preconsolidation stage. The preforms are then preheated and press formed to obtain the final part. The process stages are examined to optimize part quality and throughput versus processing parameters. A viable processing route is proposed with typical cycle times below 40s (for a plate 0.5 × 0.5m2, weighing 2kg), enabling high production capacity from one line. The mechanical performance is shown to surpass that of 40wt.% GMT and has properties equivalent to those of 40wt.% GMTex at both 20°C and 80°

Using Picture-Based Task-Analytic Instruction to Teach Students with Moderate Intellectual Disability to Email Peers without Disabilities

This preliminary study investigated the effects of using picture-based task analyses and an iPad to teach students with intellectual disability how to send and reply to emails. Three middle-school-aged students with intellectual disability as well as three peers without disabilities participated in this investigation. The intervention consisted of two 15-step task analyses: one for sending an email, and the second for replying to an email, least to most prompting, and constant time delay. Results showed students’ improved ability to send and reply to emails on an iPad with the support of picture-based task analyses. Implications for practice and future research are discussed

VOID EVOLUTION DURING STAMP-FORMING OF THERMOPLASTIC COMPOSITES

SUMMARY: A thermoplastic stamp-forming process has been investigated using glass fibre (GF), carbon fibre (CF), and hybrid carbon-glass fibre fabric materials. For monolithic GF/PA6 and CF/PA66 materials, stamping pressure was the dominating variable to achieve high mechanical properties, low void contents, and minimal void content distributions across the stamped part. Use of a hybrid flow core material composed of CF/PA66 textile skins and a GF/PA66 random fibre core reduced this tendency such that tool temperature dominated the process. The increased local flow of the core layer accommodated the varying local superficial fabric density. Use of the flow core did not significantly affect flexural properties, but with a 29% and 17% drop in tensile modulus and strength. A substantial cost saving resulted from the use of a hybrid glass and carbon structure. In mould cycle times of 30s resulted for 3mm thick parts

The Moral Economy of Heroin in ‘Austerity Britain’

This article presents the findings of an ethnographic exploration of heroin use in a disadvantaged area of the United Kingdom. Drawing on developments in continental philosophy as well as debates around the nature of social exclusion in the late-modern west, the core claim made here is that the cultural systems of exchange and mutual support which have come to underpin heroin use in this locale—that, taken together, form a ‘moral economy of heroin’—need to be understood as an exercise in reconstituting a meaningful social realm by, and specifically for, this highly marginalised group. The implications of this claim are discussed as they pertain to the fields of drug policy, addiction treatment, and critical criminological understandings of disenfranchised groups

The state of peer-to-peer network simulators

Networking research often relies on simulation in order to test and evaluate new ideas. An important requirement of this process is that results must be reproducible so that other researchers can replicate, validate and extend existing work. We look at the landscape of simulators for research in peer-to-peer (P2P) networks by conducting a survey of a combined total of over 280 papers from before and after 2007 (the year of the last survey in this area), and comment on the large quantity of research using bespoke, closed-source simulators. We propose a set of criteria that P2P simulators should meet, and poll the P2P research community for their agreement. We aim to drive the community towards performing their experiments on simulators that allow for others to validate their results

Functional Multipotency of Stem Cells: A Conceptual Review of Neurotrophic Factor-Based Evidence and Its Role in Translational Research

We here propose an updated concept of stem cells (SCs), with an emphasis on neural stem cells (NSCs). The conventional view, which has touched principally on the essential property of lineage multipotency (e.g., the ability of NSCs to differentiate into all neural cells), should be broadened to include the emerging recognition of biofunctional multipotency of SCs to mediate systemic homeostasis, evidenced in NSCs in particular by the secretion of neurotrophic factors. Under this new conceptual context and taking the NSC as a leading example, one may begin to appreciate and seek the “logic” behind the wide range of molecular tactics the NSC appears to serve at successive developmental stages as it integrates into and prepares, modifies, and guides the surrounding CNS micro- and macro-environment towards the formation and self-maintenance of a functioning adult nervous system. We suggest that embracing this view of the “multipotency” of the SCs is pivotal for correctly, efficiently, and optimally exploiting stem cell biology for therapeutic applications, including reconstitution of a dysfunctional CNS

Renewable Energy from Whisky Distillery By-products

Whisky distillery by-products draff and pot ale (PA) have an energy content that potentially can be used to decarbonize distillery heating. Draff consists of wet grains which are the residue of the first stage of whisky production. PA is the liquid residue that results from the first stage of the distillation at malt distilleries. The yearly production of distillery by-products was estimated to have increased by 27,000 tonnes (dry) in 2014. It is not feasible to store distillery by-products because of their bio-chemical nature and high volumes. Therefore, distillery by-products need to be removed from the site as they are produced. The most economical way to dispose of distillery by-products is by using them as feed stock for bioenergy. Some distilleries send draff and pot ale to AD plants, but to be useful they have to be dried and the use of fossil fuels for this makes the process uneconomical and the carbon emissions have to be deducted from any green biogas that is produced. This work showed for the first time that distillery draff could be air-gasified. The restricted ventilation Cone calorimeter method was used. An FTIR that was calibrated for 60 species was used to carry out the speciation of the product gases. The experimentally determined optimum gasification equivalence ratio (Ø) and gasification thermal efficiency for the gasification of draff were 4.5 and 90% respectively. Keywords : Draff, gasification, decarbonisation, equivalence ratio

Glycerol and Glycerol/water Gasification for the Decarbonisation of Industrial Heat

This research is aimed at using Gaseq equilibrium flame chemistry modelling, to demonstrate that wet waste crude glycerol could be air gasified to produce a Biomass Gasification Gas (BGG) for direct applications as a burner fuel for the decarbonisation of industrial heat. Glycerol is a typical biomass fuel in its composition and it is similar to the distillery waste pot ale (PA), which is about 87% water and 13% pot ale syrup (PAS). Both of these low-cost waste bio-fuels are not easy to burn in conventional burners due to their high viscosity, high boiling point and high water content. There is much agricultural waste and other industrial bio-liquid wastes that are also high in water content, including distillery waste draff, spent grains from the barley malting process and farming manure. Draff is typically 75% water. Consequently, this work investigated the influence of water on BGG composition for wet bio-waste, using glycerol/water mixtures as the demonstration of wet bio-waste. Gasification of biomass can be aided by adding steam to the air gasifier, due to the water gas shift reaction that reacts with steam and CO to produce more hydrogen. However, if the steam generator is a separate plant there are energy efficiency problems. In the present work, the gasifier is heated directly by an inline burner operating very lean and this will vaporise the water in the biomass and produce steam. The burner temperature controls the gasifier operating temperature and the yield of CO and H2, as well as moving the peak energy content of the BGG to richer gasification equivalence ratio. Water in the fuel up to 60% was predicted to still achieve gasification, but the impact on equilibrium hydrogen was only a small increase with a larger decrease in CO. With BGG gas combustion in a boiler it would be possible to recover the heat of vaporisation of water through flue gas condensation and recovery of the heat using burner inlet air cooling

Flow Properties of Tailored Net-Shape Thermoplastic Composite Preforms

A novel thermoplastic programmable preforming process, TP-P4, has been used to manufacture preforms for non-isothermal compression molding. Commingled glass and polypropylene yarns are deposited by robot onto a vacuum screen, followed by a heat-setting operation to stabilize the as-placed yarns for subsequent handling. After an optional additional preconsolidation stage, the preforms are molded by preheating and subsequent press forming in a shear edge tool. The in- and out-of-plane flow capabilities of the material were investigated, and compared to those of 40 wt% Glass Mat Thermoplastics (GMTs). Although the TP-P4 material has a fiber fraction of 60 wt%, the material could be processed to fill 77 mm deep ribs with a thickness of 3 mm, indicative of complex part production. The pressure requirements for out-of-plane flow were shown to depend on the fiber length and fiber alignment. Segregation phenomena were found to be less severe with TP-P4 than with GMT material

Human Neural Stem Cells Survive Long Term in the Midbrain of Dopamine-Depleted Monkeys After GDNF Overexpression and Project Neurites Toward an Appropriate Target

Transplanted multipotent human fetal neural stem cells (hfNSCs) significantly improved the function of parkinsonian monkeys in a prior study primarily by neuroprotection, with only 3%–5% of cells expressing a dopamine (DA) phenotype. In this paper, we sought to determine whether further manipulation of the neural microenvironment by overexpression of a developmentally critical molecule, glial cell-derived neurotrophic factor (GDNF), in the host striatum could enhance DA differentiation of hfNSCs injected into the substantia nigra and elicit growth of their axons to the GDNF-expressing target. hfNSCs were transplanted into the midbrain of 10 green monkeys exposed to 1-methyl-4-phenyl-1,2,3,6-tetrahydro-pyridine. GDNF was delivered concomitantly to the striatum via an adeno-associated virus serotype 5 vector, and the fate of grafted cells was assessed after 11 months. Donor cells remained predominantly within the midbrain at the injection site and sprouted numerous neurofilament-immunoreactive fibers that appeared to course rostrally toward the striatum in parallel with tyrosine hydroxylase-immunoreactive fibers from the host substantia nigra but did not mature into DA neurons. This work suggests that hfNSCs can generate neurons that project long fibers in the adult primate brain. However, in the absence of region-specific signals and despite GDNF overexpression, hfNSCs did not differentiate into mature DA neurons in large numbers. It is encouraging, however, that the adult primate brain appeared to retain axonal guidance cues. We believe that transplantation of stem cells, specifically instructed ex vivo to yield DA neurons, could lead to reconstruction of some portion of the nigrostriatal pathway and prove beneficial for the parkinsonian condition