6 research outputs found

    Silane modification of the flax/epoxy system interface

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    Natural fibres (NF) are normally subjected to pre-treatment to ensure good fibre to matrix bonding and consequent mechanical properties and durability. To enhance the sustainability of NF composite systems, it would be sensible to minimise processes that incur environmental burdens. This research considers that addition of silane coupling agent to epoxy resin hardener may be an alternative to the direct chemical pre-treatment of NF before composites manufacture. The current study indicates that silane-in-hardener can eliminate the pre-treatment of fibres and generates composites with optimum mechanical properties

    Sustainable Manufacture of Natural Fibre Reinforced Epoxy Resin Composites with Coupling Agent in the Hardener

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    Lignocellulosic natural fibres are hydrophilic, while many matrix systems for composites are hydrophobic. The achievement of good mechanical properties for natural fibre-reinforced polymer (NFRP) matrix composites relies on good fibre-to-matrix bonding at the interface. The reinforcement is normally coated with an amphiphilic coupling agent to promote a strong interface. A novel alternative approach is to dissolve the coupling agent in the hardener for the resin before creating the stoichiometric mix with the base epoxy resin. During composite manufacture, the hydrophilic (polar) end of the coupling agent migrates to surfaces (internal interfaces) and bonds to the fibres. The hydrophobic (non-polar) end of the coupling agent remains embedded in the mixed resin. Mechanical testing of composite samples showed that silane added directly to the matrix produced a NFRP composite with enhanced longitudinal properties. As pre-process fibre coating is no longer required, there are economic (shorter process times), environmental (elimination of contaminated solvents) and social (reduced worker exposure to chemical vapours) benefits arising from the new technique

    Experience With Bexarotene to Treat Cutaneous T-Cell Lymphomas: A Study of the Spanish Working Group of Cutaneous Lymphomas

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    Background and objectives: Bexarotene has been approved to treat advanced stage cutaneous T -cell lymphomas (CTCL) since 1999. However, very few data have been published on its long-term safety and efficacy profile. The aim of this study is to determine the tolerability to bexarotene and outcomes by collecting the 2nd largest case series to date on its long-term use vs CTCL. Material and method: This was a multicenter retrospective review of 216 patients with mycosis fungoides (174), or S & eacute;zary syndrome (42) on a 10 -year course of bexarotene alone or in combination with other therapies at 19 tertiary referral teaching hospitals. Results: A total of 133 men (62%) and 83 women (38%) were included, with a mean age of 63.5 year (27 - 95). A total of 45% were on bexarotene monotherapy for the entire study period, 22% started on bexarotene but eventually received an additional therapy, 13% were on another treatment but eventually received bexarotene while the remaining 20% received a combination therapy since the beginning. The median course of treatment was 20.78 months (1 - 114); and the overall response rate, 70.3%. Complete and partial response rates were achieved in 26% and 45% of the patients, respectively. Treatment was well tolerated, being the most common toxicities hypertriglyceridemia (79%), hypercholesterolemia (71%), and hypothyroidism (52%). No treatment -related grade 5 adverse events were reported. Conclusions: Our study confirms bexarotene is a safe and effective therapy for the long-term treatment of CTCL. (c) 2024 AEDV. Published by Elsevier Espana, S.L.U. This is an open access article under the CC BY -NC -ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

    Power Doppler signal at the enthesis and bone erosions are the most discriminative OMERACT ultrasound lesions for SpA: Results from the DEUS (Defining Enthesitis on Ultrasound in Spondyloarthritis) multicentre study

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    Objectives To assess, in spondyloarthritis (SpA), the discriminative value of the Outcome Measures in Rheumatology (OMERACT) ultrasound lesions of enthesitis and their associations with clinical features in this population. Methods In this multicentre study involving 20 rheumatology centres, clinical and ultrasound examinations of the lower limb large entheses were performed in 413 patients with SpA (axial SpA and psoriatic arthritis) and 282 disease controls (osteoarthritis and fibromyalgia). 'Active enthesitis' was defined as (1) power Doppler (PD) at the enthesis grade ≥1 plus entheseal thickening and/or hypoechoic areas, or (2) PD grade >1 (independent of the presence of entheseal thickening and/or hypoechoic areas). Results In the univariate analysis, all OMERACT lesions except enthesophytes/calcifications showed a significant association with SpA. PD (OR=8.77, 95% CI 4.40 to 19.20, p<0.001) and bone erosions (OR=4.75, 95% CI 2.43 to 10.10, p<0.001) retained this association in the multivariate analysis. Among the lower limb entheses, only the Achilles tendon was significantly associated with SpA (OR=1.93, 95% CI 1.30 to 2.88, p<0.001) in the multivariate analyses. Active enthesitis showed a significant association with SpA (OR=9.20, 95% CI 4.21 to 23.20, p<0.001), and unlike the individual OMERACT ultrasound lesions it was consistently associated with most clinical measures of SpA disease activity and severity in the regression analyses. Conclusions This large multicentre study assessed the value of different ultrasound findings of enthesitis in SpA, identifying the most discriminative ultrasound lesions and entheseal sites for SpA. Ultrasound could differentiate between SpA-related enthesitis and other forms of entheseal pathology (ie, mechanical enthesitis), thus improving the assessment of entheseal involvement in SpA

    2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery

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