The influence of consolidation force on the performance of AFP manufactured laminates

With the increasing use of carbon/glass fibre reinforced polymer composites for large components like wing skins, fuselages and fuel tanks in aircrafts and next generation of spacecraft, utilization of advanced automated manufacturing is critical for mass production. In-situ consolidation in automated fibre placement (AFP) technology through merging several manufacturing stages like cutting, curing and consolidation has opened up a wider range of applications as well as new markets for composite materials in several sectors including aerospace and automobile in large scale. Nevertheless, the quality and integrity of AFP manufactured composites is heavily dependent on large number of variables and parameters like lay-up speed, curing/melting temperature and consolidation force. In order to establish and understand a correlation between the key parameters in AFP and the mechanical properties, several parametric experiments were performed. This is done through manufacturing uni-directional carbon fibre reinforced polymer laminates and identifying some of their main mechanical properties at different location along the length of samples. It was found that, the strength of laminates at different locations is critically dependent on the effect of those parameters

Grey Matter Etymology and the neuron(e).

‘Neuron’ or ‘neurone’? While it is often assumed that these different spellings reflect usage of American versus British English, there are also inconsistencies within these cultural boundaries. Mehta et al. review historical, etymological and linguistic evidence concerning the spelling of ‘neuron(e)’ and conclude that the only correct spelling is ‘neuron’

Using Qualitative Methods to Explore Farrier-Related Barriers to Successful Farriery Interventions for Equine Welfare in India

Farriery is a critical component of healthcare services for working equids. However, in India, an informal workforce, lack of structured training facilities and non-implementation of farriery regulations pose challenges for quality farriery. Brooke India, an equine welfare organisation, has undertaken many initiatives aiming to improve farriery services, including technical training and engagement with equid-owning communities. However, this has met with varying success. The study aimed to identify factors that prevent farriers providing quality farriery services. Focus-group discussions were conducted with farriers from two districts of Uttar Pradesh with varying programme outcomes. Within each area, farriers were grouped according to previous level of engagement with Brooke programmes. Demand for services, farrier status, the external environment and technical training and knowledge were identified as key elements that affected farriery work. These factors were very context specific: in areas where brick kilns provided the majority of customers, recent closures had resulted in an increase in those farriers’ feeling of insecurity. A systems approach to improving farriery services, taking these factors into account, is advised. Mentoring-based capacity building, which is closely aligned to farrier needs and expectations, is expected to have positive results in terms of technical skill and farrier engagement

Modelling of the low-impulse blast behaviour of fibre–metal laminates based on different aluminium alloys

A parametric study has been undertaken in order to investigate the influence of the properties of the aluminium alloy on the blast response of fibre–metal laminates (FMLs). The finite element (FE) models have been developed and validated using experimental data from tests on FMLs based on a 2024-O aluminium alloy and a woven glass–fibre/polypropylene composite (GFPP). A vectorized user material subroutine (VUMAT) was employed to define Hashin’s 3D rate-dependant damage constitutive model of the GFPP. Using the validated models, a parametric study has been carried out to investigate the blast resistance of FML panels based on the four aluminium alloys, namely 2024-O, 2024-T3, 6061-T6 and 7075-T6. It has been shown that there is an approximation linear relationship between the dimensionless back face displacement and the dimensionless impulse for all aluminium alloys investigated here. It has also shown that the residual displacement of back surface of the FML panels and the internal debonding are dependent on the yield strength of the aluminium alloy

A whole genome screen for association with multiple sclerosis in portuguese patients

Multiple sclerosis (MS) is common in Europe affecting up to 1:500 people. In an effort to identify genes influencing susceptibility to the disease, we have performed a population-based whole genome screen for association. In this study, 6000 microsatellite markers were typed in separately pooled DNA samples from MS patients (n = 188) and matched controls (n = 188). Interpretable data was obtained from 4661 of these markers. Refining analysis of the most promising markers identified 10 showing potential evidence for association.SERONO (Portugal).Fundação para a Ciência e a Tecnologia (FCT) - grant FRH/BD/9111/2002.British Council/ICCTI.Wellcome Trust, Multiple Sclerosis Societies of the United States and Great Britain, Multiple Sclerosis International Federation - GAMES project - grant 057097

Histomorphometric evaluation of bone healing in rabbit fibular osteotomy model without fixation

<p>Abstract</p> <p>Background</p> <p>Animal models of fracture consolidation are fundamental for the understanding of the biological process of bone repair in humans, but histological studies are rare and provide only qualitative results. The objective of this article is to present the histomorphometric study of the bone healing process using an experimental model of osteotomy in rabbit fibula without interference of synthesis material.</p> <p>Methods</p> <p>Fifteen rabbits were submitted to fibular osteotomy without any fixation device. Groups of five animals were submitted to pharmacological euthanasia during a period of one (group A), two (group B) and four weeks (group C) after osteotomy. Histomorphometric evaluation was performed in the histological sections.</p> <p>Results</p> <p>During week one there was intense cellularity (67/field), a large amount of woven bone (75.7%) and a small amount of lamellar bone (7.65%). At two weeks there was a decrease in woven bone (41.59%) and an increase in lamellar bone (15.16%). At four weeks there was a decrease of cellularity (19.17/field) and lamellar bone (55.56%) exceeded the quantity of woven bone (31.68%).</p> <p>Conclusion</p> <p>Histomorphometric (quantitative) evaluation of the present study was shown to be compatible with bone healing achieved in qualitative experimental models that have been commended in the literature.</p

Multi-centre parallel arm randomised controlled trial to assess the effectiveness and cost-effectiveness of a group-based cognitive behavioural approach to managing fatigue in people with multiple sclerosis

Abstract (provisional) Background Fatigue is one of the most commonly reported and debilitating symptoms of multiple sclerosis (MS); approximately two-thirds of people with MS consider it to be one of their three most troubling symptoms. It may limit or prevent participation in everyday activities, work, leisure, and social pursuits, reduce psychological well-being and is one of the key precipitants of early retirement. Energy effectiveness approaches have been shown to be effective in reducing MS-fatigue, increasing self-efficacy and improving quality of life. Cognitive behavioural approaches have been found to be effective for managing fatigue in other conditions, such as chronic fatigue syndrome, and more recently, in MS. The aim of this pragmatic trial is to evaluate the clinical and cost-effectiveness of a recently developed group-based fatigue management intervention (that blends cognitive behavioural and energy effectiveness approaches) compared with current local practice. Methods This is a multi-centre parallel arm block-randomised controlled trial (RCT) of a six session group-based fatigue management intervention, delivered by health professionals, compared with current local practice. 180 consenting adults with a confirmed diagnosis of MS and significant fatigue levels, recruited via secondary/primary care or newsletters/websites, will be randomised to receive the fatigue management intervention or current local practice. An economic evaluation will be undertaken alongside the trial. Primary outcomes are fatigue severity, self-efficacy and disease-specific quality of life. Secondary outcomes include fatigue impact, general quality of life, mood, activity patterns, and cost-effectiveness. Outcomes in those receiving the fatigue management intervention will be measured 1 week prior to, and 1, 4, and 12 months after the intervention (and at equivalent times in those receiving current local practice). A qualitative component will examine what aspects of the fatigue management intervention participants found helpful/unhelpful and barriers to change. Discussion This trial is the fourth stage of a research programme that has followed the Medical Research Council guidance for developing and evaluating complex interventions. What makes the intervention unique is that it blends cognitive behavioural and energy effectiveness approaches. A potential strength of the intervention is that it could be integrated into existing service delivery models as it has been designed to be delivered by staff already working with people with MS. Service users will be involved throughout this research. Trial registration: Current Controlled Trials ISRCTN7651747

Dynamic mode II delamination in through thickness reinforced composites

Through thickness reinforcement (TTR) technologies have been shown to provide effective delamination resistance for laminated composite materials. The addition of this reinforcement allows for the design of highly damage tolerant composite structures, specifically when subjected to impact events. The aim of this investigation was to understand the delamination resistance of Z-pinned composites when subjected to increasing strain rates. Z-pinned laminated composites were manufactured and tested using three point end notched flexure (3ENF) specimens subjected to increasing loading rates from quasi-static (~0m/s) to high velocity impact (5m/s), using a range of test equipment including drop weight impact tower and a split Hopkinson bar (SHPB). Using a high speed impact camera and frame by frame pixel tracking of the strain rates, delamination velocities as well as the apparent fracture toughness of the Z-pinned laminates were measured and analysed. Experimental results indicate that there is a transition in the failure morphology of the Z-pinned laminates from quasi-static to high strain rates. The fundamental physical mechanisms that generate this transition are discussed

Heterogeneity at the HLA-DRB1 locus and risk for multiple sclerosis.

Variation in major histocompatibility complex genes on chromosome 6p21.3, specifically the human leukocyte antigen HLA-DR2 or DRB1*1501-DQB1*0602 extended haplotype, confers risk for multiple sclerosis (MS). Previous studies of DRB1 variation and both MS susceptibility and phenotypic expression have lacked statistical power to detect modest genotypic influences, and have demonstrated conflicting results. Results derived from analyses of 1339 MS families indicate DRB1 variation influences MS susceptibility in a complex manner. DRB1*15 was strongly associated in families (P=7.8x10(-31)), and a dominant DRB1*15 dose effect was confirmed (OR=7.5, 95% CI=4.4-13.0, P<0.0001). A modest dose effect was also detected for DRB1*03; however, in contrast to DRB1*15, this risk was recessive (OR=1.8, 95% CI=1.1-2.9, P=0.03). Strong evidence for under-transmission of DRB1*14 (P=5.7x10(-6)) even after accounting for DRB1*15 (P=0.03) was present, confirming a protective effect. In addition, a high risk DRB1*15 genotype bearing DRB1*08 was identified (OR=7.7, 95% CI=4.1-14.4, P<0.0001), providing additional evidence for trans DRB1 allelic interactions in MS. Further, a significant DRB1*15 association observed in primary progressive MS families (P=0.0004), similar to relapsing-remitting MS families, suggests that DRB1-related mechanisms are contributing to both phenotypes. In contrast, results obtained from 2201 MS cases argue convincingly that DRB1*15 genotypes do not modulate age of onset, or significantly influence disease severity measured using expanded disease disability score and disease duration. These results contribute substantially to our understanding of the DRB1 locus and MS, and underscore the importance of using large sample sizes to detect modest genetic effects, particularly in studies of genotype-phenotype relationships