723 research outputs found

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

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    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°

    The state of peer-to-peer network simulators

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    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

    The Moral Economy of Heroin in ‘Austerity Britain’

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    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

    Post-Construction Support and Sustainability in Community-Managed Rural Water Supply

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    Executive Summary This volume reports the main findings from a multi-country research project that was designed to develop a better understanding of how rural water supply systems are performing in developing countries. We began the research in 2004 to investigate how the provision of support to communities after the construction of a rural water supply project affected project performance in the medium term. We collected information from households, village water committees, focus groups of village residents, system operators, and key informants in 400 rural communities in Bolivia, Ghana, and Peru; in total, we discussed community water supply issues with approximately 10,000 individuals in these communities. To our surprise, we found the great majority of the village water systems were performing well. Our findings on the factors influencing their sustainability will, we hope, be of use to policy makers, investors, and managers in rural water supply

    Using statistical and artificial neural networks to predict the permeability of loosely packed granular materials

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    Well-known analytical equations for predicting permeability are generally reported to overestimate this important property of porous media. In this work, more robust models developed from statistical (multivariable regression) and Artificial Neural Network (ANN) methods utilised additional particle characteristics [‘fines ratio’ (x50/x10) and particle shape] that are not found in traditional analytical equations. Using data from experiments and literature, model performance analyses with average absolute error (AAE) showed error of ~40% for the analytical models (Kozeny–Carman and Happel–Brenner). This error reduces to 9% with ANN model. This work establishes superiority of the new models, using experiments and mathematical techniques

    Interleukin-10 enhances the intestinal epithelial barrier in the presence of corticosteroids through p38 MAPK activity in Caco-2 monolayers : a possible mechanism for steroid responsiveness in ulcerative colitis

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    Altres ajuts: 2012 Spanish Gastroenterological Association i CIBER G0034Glucocorticosteroids are the first line therapy for moderate-severe flare-ups of ulcerative colitis. Despite that, up to 60% of patients do not respond adequately to steroid treatment. Previously, we reported that low IL-10 mRNA levels in intestine are associated with a poor response to glucocorticoids in active Crohn's disease. Here, we test whether IL-10 can favour the response to glucocorticoids by improving the TNFα-induced intestinal barrier damage (assessed by transepithelial electrical resistance) in Caco-2 monolayers, and their possible implications on glucocorticoid responsiveness in active ulcerative colitis. We show that the association of IL-10 and glucocorticoids improves the integrity of TNFα-treated Caco-2 cells and that p38 MAPK plays a key role. In vitro, IL-10 facilitates the nuclear translocation of p38 MAPK-phosphorylated thereby modulating glucocorticoids-receptor-α, IL-10-receptor-α and desmoglein-2 expression. In glucocorticoids-refractory patients, p38 MAPK phosphorylation and membrane desmoglein-2 expression are reduced in colonic epithelial cells. These results suggest that p38 MAPK-mediated synergism between IL-10 and glucocorticoids improves desmosome straightness contributing to the recovery of intestinal epithelium and reducing luminal antigens contact with lamina propria in ulcerative colitis. This study highlights the link between the intestinal epithelium in glucocorticoids-response in ulcerative colitis

    Clonal human fetal ventral mesencephalic dopaminergic neuron precursors for cell therapy research

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    A major challenge for further development of drug screening procedures, cell replacement therapies and developmental studies is the identification of expandable human stem cells able to generate the cell types needed. We have previously reported the generation of an immortalized polyclonal neural stem cell (NSC) line derived from the human fetal ventral mesencephalon (hVM1). This line has been biochemically, genetically, immunocytochemically and electrophysiologically characterized to document its usefulness as a model system for the generation of A9 dopaminergic neurons (DAn). Long-term in vivo transplantation studies in parkinsonian rats showed that the grafts do not mature evenly. We reasoned that diverse clones in the hVM1 line might have different abilities to differentiate. In the present study, we have analyzed 9 hVM1 clones selected on the basis of their TH generation potential and, based on the number of v-myc copies, v-myc down-regulation after in vitro differentiation, in vivo cell cycle exit, TH+ neuron generation and expression of a neuronal mature marker (hNSE), we selected two clones for further in vivo PD cell replacement studies. The conclusion is that homogeneity and clonality of characterized NSCs allow transplantation of cells with controlled properties, which should help in the design of long-term in vivo experimentsThis work was supported by grants from the Spanish Ministry of Economy and Competitiveness (formerly Science and Innovation; PLE2009-0101, SAF2010-17167), Comunidad Autónoma Madrid (S2011-BMD-2336), Instituto Salud Carlos III (RETICS TerCel, RD06/0010/0009) and European Union (Excell, NMP4-SL-2008-214706). This work was also supported by an institutional grant from Foundation Ramón Areces to the Center of Molecular Biology Severo Ocho

    The ‘one who knocks’ and the ‘one who waits’: Gendered violence in Breaking Bad

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    This article provides a cultural criminological analysis of the acclaimed US television series, Breaking Bad. It is argued here that – as a cultural text – Breaking Bad is emblematic of an agenda for change surrounding criminological theories of peoples’ propensity to do harm to one another. To exemplify this, the show’s central (male) protagonist is revealed to undergo a complete biosocial transformation into a violent offender and, as such, to demonstrate the need for criminological theory to recognise and further reflect upon this process. However, at the same time, the (re)presented inability of the show’s female characters to do the same is indicative of a number of gender-related questions that progressive criminological theories of violence need to answer. In considering these two fields in tandem, the show’s criminological significance is established; it is symbolic of the need for criminology to afford greater recognition to the nuanced intersections of both biological and sociological factors in the genesis and evolution of violent human subjectivities

    VOID EVOLUTION DURING STAMP-FORMING OF THERMOPLASTIC COMPOSITES

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    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
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