Processing of continuous fibre reinforced thermoplastics

ECCM15 - 15TH EUROPEAN CONFERENCE ON COMPOSITE MATERIALS, Venice, Italy, 24-28 June 2012Towpregs based on different fibres and thermoplastic matrices were processed for highly demanding and more commercial applications by different composite processing technologies. In the technologies used, compression moulding and pultrusion, the final composite pr ocessing parameters were studied in order to obtain composites with adequate properties at industrial compatible production rates. The produced towpregs were tested to verify its polymer content and degree of impregnation. The obtained results have shown t hat the coating line enabled to produce, with efficiency and industrial scale speed rates, thermoplastic matrix towpregs that may be used to manufacture composites for advanced and larger volume commercial markets

Compression molding of pultruded carbon reinforced thermoplastic composites

Historically, thermoset resins have dominated the composite industry but they start to be replaced by thermoplastics. In this study two different thermoplastic matrix carbon reinforced pre-impregnated materials were used, one produced in our laboratories (towpreg) and another obtained from coextrusion process (PCT). Carbon fibre and two different thermoplastic matrices (polypropylene and PRIMOSPIRE®) were selected for the production of the pre-impregnated materials. Heated compression moulding and pultrusion were the two manufacturing technologies used to obtain composite plates and profiles for study. The optimization of those processes was made by studying the influence of the most relevant processing parameters in the final properties of the produced carbon fibres thermoplastic matrix pre-impregnated materials and composites. The composite relevant mechanical properties were determined and the final composites were submitted to Dynamic Mechanical Analysis (DMA), Scanning Electron Microscope (SEM), optical microscopy and calcination tests. The determination of the fiber volume fraction of all studied composite was obtained comparing the results of thermogravimetric analysis (TGA), SEM and calcination tests.info:eu-repo/semantics/publishedVersio

Processing of carbon reinforced thermoplastic pre-impregnated materials

The aim of this work is to produce and optimize the processing of carbon fibres thermoplastic matrix pre-impregnated materials (towpregs and PCT´s). Pultrusion and heated compression moulding were the selected manufacturing methods for processing all carbon fibres thermoplastic matrix pre-impregnated materials into composite parts. The optimization of those processes was made by studying the influence of the most relevant processing parameters in the final properties of the produced carbon fibres thermoplastic matrix pre-impregnated materials and composites. The method of Taguchi / DOE (Design of Experiments) was used to achieve this aim as it allowed making more rational choices of processing windows. The composite relevant mechanical properties were determined and studied. The final composites were also submitted to SEM microscopy analysis.info:eu-repo/semantics/publishedVersio

Production and processing of pre-impregnated thermoplastic tapes by pultrusion and compression moulding

Although there is no doubt that composite materials are the future of lightweight structures and components, most of composites currently produced are made from thermoset polymers, which are not able to be recycled or reprocessed. In contrast, thermoplastic polymers offer the possibility to recycle and reprocess and when combined with a fibrous reinforcement, provide interesting mechanical properties. This work reviews the production of two thermoplastic preimpregnated materials in a tape form, one of which is produced on new prototype equipment developed in our laboratories. The method for the production of tape is described, and the prepregs presented here were subjected to two processing techniques. The first processing method, pultrusion, is an efficient and autonomous method to produce composite profiles, marking itself as a continuous and cost-effective way to produce these materials. Pultrusion bars were then subjected to heated compression moulding, a process that allows to obtain more complex-shaped parts. The second method, heated compression moulding, is a relatively simple process which was used to obtain composite laminates. The pultrusion bars and composite laminates were then subjected to mechanical testing to evaluate the levels of consolidation of the final material. A microscope testing was also carried out to analyse the dispersion of fibres and polymer, as well as the amount of voids present in the composite.Agência Nacional para a Inovação - ANI, Projeto ADD.CompFiber 6960

Efficacy and Safety of Intravitreal Aflibercept Treat and Extend for Polypoidal Choroidal Vasculopathy in the ATLANTIC Study: A Randomized Clinical Trial

Aflibercept; Efficacy; Polypoidal choroidal vasculopathyAflibercept; Eficacia; Vasculopatía coroidea polipoideaAflibercept; Eficàcia; Vasculopatia coroidal polipoidalImportance: Polypoidal choroidal vasculopathy (PCV) is far less common and studied in a Caucasian population than in an Asian population, and the optimal treatment approach remains to be confirmed. Methods: A 52-week, double-masked, sham-controlled, phase 4, investigator-initiated randomized clinical trial (RCT) in naive symptomatic Caucasian patients with PCV treated with aflibercept in a treat-and-extend regimen (T&E) (intravitreal aflibercept injection [IVAI] T&E). Patients were randomized at week 16 to receive IVAI T&E plus either sham photodynamic therapy (PDT) or standard fluence PDT with verteporfin. The main outcome measures were changes in best-corrected visual acuity (BCVA) from baseline to 52 weeks and polyp occlusion at week 52. Data are presented as median (interquartile range [IQR]) for BCVA, number of IVAI, and change in central retinal thickness (CRT). Results: Of the 50 patients included in the study, 48 patients completed the 52 weeks of follow-up. During this period, a significant median (IQR) BCVA gain of 6 [2–12] Early Treatment Diabetic Retinopathy Study letters was observed for all patients (p < 0.001), after 8 (7–9) injections, with a significant reduction of −93.0 [−154.0, −44.0] µm in central macular thickness (p < 0.001). Using indocyanine green angiography, a complete occlusion of polypoidal lesions was documented in 72% of the cases. Still, no significant difference was detected between the sham PDT and the aflibercept PDT arms, at week 52, for BCVA change (6.5 [2–11] vs. 5 [2–13] letters (p = 0.98)), number of IVAIs (8.5 [7–9] vs. 8 [7–9] (p = 0.21)), change in CRT (−143 [−184; −47] vs. −89 [−123; −41.5] µm [p = 0.23]), and rates of complete polyp occlusion: 77 versus 68% (p = 0.53) or presence of fluid: 68 versus 57% (p = 0.56). No serious ocular adverse events were registered in the 2 arms. Conclusions and Relevance: To our knowledge, this is the first RCT to compare aflibercept T&E monotherapy with aflibercept T&E plus verteporfin PDT in a Caucasian population with PCV. Aflibercept monotherapy in a T&E showed to be effective and safe with a significant median BCVA improvement of 6 letters and a complete occlusion of polypoidal lesions in near 3 quarters of the eyes, at 1 year. As only 22% of the eyes underwent PDT treatment, the benefit of combined treatment for PCV in Caucasian patients could not be definitively elucidated from this study. Trial Registration: The clinical trial was registered in ClinicalTrials.gov Identifier NCT02495181 and the European Union Drug Regulating Authorities Clinical Trials Database EudraCT No. 2015-001368-20.Funding/support: This investigator-initiated study was financially supported by Bayer. Role of the funder/sponsor: Bayer had no role in the design and conduct of the study, collection, management, analysis, and interpretation of the data

Integrated water management in the Seven Cities basin

Copyright © 2008 Springer.The Sete Cidades lake in the Azores, is located in a volcanic crater. Increased frequency of logging (380 hectares of production forests) and the use of fertilizers on pastures and forages (450 hectares) that sustain 750 cows, provide direct employment to 67 farmers and induce employment to more 50 actives, but also increases the eutrophycation and sedimentation of the lake. To address the issue an integrated model generates efficient land use scenarios for different degrees of phosphorus emissions with related effects in the water quality. The model is used to obtain various indicators for each scenario that feed a multi-objective program able to find the dominant solutions. The final solution is chosen by the politicians: 600 cows that produce 3.0 millions of milk, provide direct employment to 55 farmers and induce employment to more 41 actives. This, jointly with a partial stream deviation, allows a reduction of 63% of the phosphorus load to the lake. Compensatory measures pay the farmers their losses and compensate the community for the lost employment

VINHOS QUE PENSAM - parte I/III GESTÃO DO VIGOR VEGETATIVO DA VINHA A PARTIR DE SENSORES ATIVOS MUTIESPECTRAIS PRÓXIMOS

Costumo dizer que o projeto “Vinhos que pensam” nasceu de um aperto de mão entre a equipa de Agricultura de Precisão da Universidade de Évora e a Fundação Eugénio de Almeida, nasceu sem financiamento próprio mas com uma visão muito clara de criar valor social na área da vitivinicultura Alentejana. Passados 6 anos, julgamos que o conhecimento produzido é relevante para a atividade e gestão vitivinícola Alentejana, no entanto, novas perguntas surgem todos os anos e dessa forma somos alimentados na motivação de prosseguir com este projeto, ao qual, outras entidades e vontades se vão agora também associando. A Agrobótica, muito recentemente, desafiou-nos a apresentar os resultados mais relevantes do projeto “Vinhos que pensam” e com o maior prazer lhe dissemos que sim, no entanto, colocou-se-nos um problema, os resultados mais relevantes, muito dificilmente caberiam num único artigo, como tal, decidimos dividir tais resultados em três artigos, este primeiro mais virado para os aspetos da gestão do vigor da vegetação da vinha; o segundo mais virado para os sensores geoelétricos do solo e sua aplicação na gestão e estudo do solo; e por fim, um terceiro mais virado para aspetos da nutrição das plantas considerando a interação solo/planta e a utilização dos sensores multiespectrais

Effective cytocompatible nanovectors based on serine-derived gemini surfactants and monoolein for small interfering RNA delivery

Supplementary data to this article can be found online athttps://doi.org/10.1016/j.jcis.2020.09.077.Non-viral gene therapy based on gene silencing with small interfering RNA (siRNA) has attracted great interest over recent years. Among various types of cationic complexation agents, amino acid-based surfactants have been recently explored for nucleic acid delivery due to their low toxicity and high biocompatibility. Monoolein (MO), in turn, has been used as helper lipid in liposomal systems due to its ability to form inverted nonbilayer structures that enhance fusogenicity, thus contributing to higher transfection efficiency. In this work, we focused on the development of nanovectors for siRNA delivery based on three gemini amino acid-based surfactants derived from serine (12Ser)2N12, amine derivative; (12Ser)2COO12, ester derivative; and (12Ser)2CON12, amide derivative individually combined with MO as helper lipid. The inclusion of MO in the cationic surfactant system influences the morphology and size of the mixed aggregates. Furthermore, the gemini surfactant:MO systems showed the ability to efficiently complex siRNA, forming stable lipoplexes, in some cases clearly depending on the MO content, without inducing significant levels of cytotoxicity. High levels of gene silencing were achieved in comparison with a commercially available standard indicating that these gemini:MO systems are promising candidates as lipofection vectors for RNA interference (RNAi)-based therapies.The authors acknowledge Fundação para a Ciência e a Tecnolo-gia (FCT) for financial support through projects UIDB/00081/2020 and UIDB/50006/2020. This work was supported by the‘‘Contrato-Programa” UIDB/04050/2020 funded by national fundsthrough the FCT I.P. Dr. Marisa Passos is gratefully acknowledged for help with the statistical analysis of cytotoxicity data. Fundingby the CCDR-N/NORTE2020/Portugal2020 through project DESign-BIOtechHealth (ref. Norte-01-0145-FEDER-000024) is also acknowledged. I. S. Oliveira and S.G. Silva also acknowledge finan-cial support from FCT through PhD grant SFRH/BD/108629/2015 and Individual Call to Scientific Employment Stimulus - CEEC Indi-vidual grant CEECIND/01932/2017, respectivelyinfo:eu-repo/semantics/publishedVersio