Processing parameters in laser powder bed fusion metal additive manufacturing

JPO acknowledges Fundação para a Ciência e a Tecnologia (FCT - MCTES) for its financial support via the projects UIDB/00667/2020 and UIDB/50025/2020 .As metallic additive manufacturing grew in sophistication, users have requested greater control over the systems, namely the ability to fully change the process parameters. The goal of this manuscript is to review the effects of major process parameters on build quality (porosity, residual stress, and composition changes) and materials properties (microstructure and microsegregation), and to serve as a guide on how these parameters may be modified to achieve specific design goals for a given part. The focus of this paper is on laser powder bed fusion, but elements can be applied to electron beam powder bed fusion or direct energy deposition techniques.publishersversionpublishe

Nitric oxide genotoxicity protection by Ginkgo biloba extract

Over the last years, the Ginkgo biloba plant has grown a considerably good reputation within the scientific community and today its potential in terms of beneficial effects is well sustained in the literature [1]. Most of the studies involving the use of plant material, however, only face their antioxidant properties and just a little was explored relatively to their antigenotoxic activity. The excessive production of oxidative species, being reactive oxygen species (ROS) or reactive nitrogen species (RNS), can be stressful to the cell to a point where they compromise survival. In between their molecular targets, ROS can affect DNA, possibly causing the loss of its stability and integrity, imposing a very dangerous threat. NO is recognized for its biological roles in the regulation of vasodilation, and nervous system and immune system signaling as well as for its potentially adverse effects [2]. Depending on the molecules NO encounters inside the cell, it may oxidize into peroxynitrite or dinitrogen trioxide (among many others), both molecules being able to interact with and modify DNA [3]. The chemical analysis of the ethanolic Ginkgo biloba extract (GBE), revealed the presence of some characteristic compounds.. Also, a protective effect against SNP was observed in viability assays, in which fission yeast Schizosaccharomyces pombe wild type strains and DNA repair-affected mutants were used. Cell cycle analysis revealed that incubation with GBE alone causes a quicker advance in cell cycle progression and that treatment with GBE slightly reduces the delay caused by SNP. Finally, experiments involving the oxidative stress response protein Pap1 fused with GFP pointed to a possible protection mechanism, where cell interaction with the extract may be functioning as a mild stress elicitor, preparing cells for the stress induced by NO. Putting all the evidence together, GBE protects cells from the effect of SNP through a DNA-repair independent mechanism, which may involve the scavenging of NO and subsequent decrease in DNA modifications, and/or the signalling of oxidative stress-response proteins preventing the excessive accumulation of oxidant molecules.This work is supported by: European Investment Funds by FEDER/COMPETE/POCI– Operacional Competitiveness and Internacionalization Programme, under Project POCI-01-0145-FEDER-006958 and National Funds by FCT - Portuguese Foundation for Science and Technology, under the project UID/AGR/04033/2013.info:eu-repo/semantics/publishedVersio

Pathway for cyanotoxin valorization: microscystin as case study

Book of Abstracts of CEB Annual Meeting 2017info:eu-repo/semantics/publishedVersio

Biodegradation of Plastics and Formation of PHA Bioplastics—A Circular Bioeconomy Approach

This work is financed by national funds from FCT—Fundação para a Ciência e a Tecnologia, IP, in the scope of the project UIDP/04378/2020 of the Research Unit on Applied Molecular Biosciences—UCIBIO and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy—i4HB, and UID/CTM/50025/2020-2023 of the Research Unit on Materials Science—CENIMAT–I3N. FCT/MCTES through project grants PTDC/QUIQUI/119116/2010, PTDC/GEO-FIQ/5162/2014, , and PTDC/EEI-EEE/0415/2021.Plastics are present in the majority of daily-use products worldwide. Due to society’s production and consumption patterns, plastics are accumulating in the environment, causing global pollution issues and intergenerational impacts. Our work aims to contribute to the development of solutions and sustainable methods to mitigate this pressing problem, focusing on the ability of marine-derived actinomycetes to accelerate plastics biodegradation and produce polyhydroxyalkanoates (PHAs), which are biodegradable bioplastics. The thin plastic films’ biodegradation was monitored by weight loss, changes in the surface chemical structure (Infra-Red spectroscopy FTIR-ATR), and by mechanical properties (tensile strength tests). Thirty-six marine-derived actinomycete strains were screened for their plastic biodegradability potential. Among these, Streptomyces gougerotti, Micromonospora matsumotoense, and Nocardiopsis prasina revealed ability to degrade plastic films—low-density polyethylene (LDPE), polystyrene (PS) and polylactic acid (PLA) in varying conditions, namely upon the addition of yeast extract to the culture media and the use of UV pre-treated thin plastic films. Enhanced biodegradation by these bacteria was observed in both cases. S. gougerotti degraded 0.56% of LDPE films treated with UV radiation and 0.67% of PS films when inoculated with yeast extract. Additionally, N. prasina degraded 1.27% of PLA films when these were treated with UV radiation, and yeast extract was added to the culture medium. The main and most frequent differences observed in FTIR-ATR spectra during biodegradation occurred at 1740 cm−1, indicating the formation of carbonyl groups and an increase in the intensity of the bands, which indicates oxidation. Young Modulus decreased by 30% on average. In addition, S. gougerotti and M. matsumotoense, besides biodegrading conventional plastics (LDPE and PS), were also able to use these as a carbon source to produce degradable PHA bioplastics in a circular economy conceptpublishersversionpublishe

Prescription and Effects of Cardiorespiratory Training in Individuals with Intellectual Disability: a Systematic Review

This study aims to systematize effects of cardiorespiratory training (CT) programs in individuals with intellectual disability (ID) and identifying the fundamental and structuring aspects for the prescription of CT. This systematic review was carried out through four databases (Pubmed, Web of Science, Scopus, and SPORTDiscus), considering data from the period between 2013 and 2022. From 257 studies, 12 studies were included in this systematic review. Three studies used interval CT, while seven used continuous CT. Seven were carried out in the population with Down syndrome, while only three were carried out with participants with ID. The CT programs had the following characteristics: duration of 8 to 12 weeks, weekly frequency of three sessions, for 20 to 60 min, the intensity of 50% to 80% of maximal heart rate or 70% to 80% of peak oxygen consumption, using an ergometer cycle or an outdoor walking. The studies reported improvements in cardiorespiratory function, lipid, hemodynamic and metabolic profile, body composition, and neuromuscular and cognitive capacity. This review presents characteristics and recommendations that technicians can follow when structuring, prescribing, and implementing CT programs to individuals with ID.info:eu-repo/semantics/publishedVersio

Forming defects prediction in cup drawing and embossing of a thick steel sheet

The accurate prediction of forming defects is fundamental for the virtual try-out of metallic sheet components. However, the constitutive model can have a strong impact on the numerical predictions, namely the cup earing, the occurrence of wrinkles and the tearing failure. The process conditions considered in this work are the ones established for the “Benchmark 2 - Cup Drawing of Anisotropic Thick Steel Sheet”, proposed under the Numisheet 2018 international conference. The axisymmetric cups are obtained from a steel sheet with 2.8 mm of thickness, resorting to different process conditions to induce different defects. The advanced yield criterion proposed by Cazacu and Barlat is used to define the anisotropic behavior of the blank. The calibration of the material parameters is carried out by fitting the following experimental data from: (i) uniaxial tensile tests performed in every 15ºto the rolling direction; (ii) biaxial tension tests to evaluate the directions of the plastic strain rates in the first quadrant of the yield loci. The numerical predictions are compared with the experimental measurements, allowing to assess the accuracy of the finite element model to predict each type of forming defect. The cup earing and the strain localization are accurately predicted, while the wrinkles amplitude is clearly underestimated.The authors gratefully acknowledge the financial support of the Portuguese Foundation for Science and Technology (FCT) under the projects with reference PTDC/EME-EME/30592/2017 and PTDC/EME-EME/31657/2017 and by European Regional Development Fund (ERDF) through the Portugal 2020 program and the Centro 2020 Regional Operational Programme (CENTRO- 01-0145-FEDER-031657) under the project MATIS (CENTRO-01-0145-FEDER-000014) and UIDB/00285/2020. We also would like to acknowledge the benchmark committee to make available the experimental data used in the present study

Comparison of harvesting methods for the cyanobacteria Microcystis aeruginosa

BioTech 2017 and 7th Czech-Swiss Symposium with ExhibitionMicrocystis aeruginosa is a wellknown cyanobacterium that has been spreading all over the world due to increased temperatures and eutrophication of water bodies caused by intensive anthropogenic activities. This toxin-producing microorganism is frequently responsible for diminishing water quality and causing intoxication of humans and animals. Due to this, its intracellular cyanotoxin – microcystin (MC) – is commonly used as tool for molecular and cell biology studies or as a standard in human and environmental risk assessment assays. Moreover, MC is a promising anticancer/antitumor drug candidate and a possible antimicrobial, antifungal, antialgal and insecticide agent. Despite MC’s potential application in several biotechnological fields, its high production costs significantly contribute for the prohibitive selling prices (28000 e/mg). Thus, improvements in process’ cost-effectiveness is needed, especially in terms of downstream processing techniques which are probably the major bottlenecks of cyanobacteria production at large scale, commonly representing 20-30 % of the total costs. Bearing this in mind, this study aimed at optimizing harvesting of M. aeruginosa induced by pH change and compares the optimal conditions obtained with the use of three different flocculant agents: chitosan, ferric chloride, and aluminium chloride. Harvesting induced by pH was assessed by testing pH values ranging between 2 and 14. Despite the fact that harvesting efficiencies above 90 % were obtained for most pH values, pH 2 was the one where higher sedimentation rate was observed and consequently the chosen method to compare with the three flocculants. Aluminium chloride addition was found to be the most efficient method, reaching 93 % of sedimentation efficiency within the first 2 h. These results are in agreement with zeta potential measurements where cells presented nearly neutral (approx. 0 mV) charge, while positive or negative charges where achieved using the other three methodologies.This research work was supported by the grant SFRH/BPD/98694/2013 (Bruno Fernandes) and SFRH/BD/52335/2013 (Pedro Geada) from Fundação para a Ciência e a Tecnologia (Portugal). Luís Loureiro is recipient of a fellowship supported by a doctoral advanced training (call NORTE-69-2015-15) funded by the European Social Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684), Project UID/Multi/04423/2013, Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462), FCT Strategic Project of UID/BIO/04469/2013 unit, by the project NOVELMAR (reference NORTE-01-0145-FEDER-000035), co-financed by the North Portugal Regional Operational Programme (Norte 2020) under the National Strategic Reference Framework (NSRF), through the ERDF, and by BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

Heart defibrillation : relationship between pacing threshold and defibrillation probability

Considering the clinical importance of the ventricular fibrillation and that the most used therapy to reverse it has a critical side effect on the cardiac tissue, it is desirable to optimize defibrillation parameters to increase its efficiency. In this study, we investigated the influence of stimuli duration on the relationship between pacing threshold and defibrillation probability. We found out that 0.5-ms-long pulses had a lower ratio of defibrillation probability to the pacing threshold, although the higher the pulse duration the lower is the electric field intensity required to defibrillate the hearts. The appropriate choice of defibrillatory shock parameters is able to increase the efficiency of the defibrillation improving the survival chances after the occurrence of a severe arrhythmia. The relationship between pulse duration and the probability of reversal of fibrillation shows that this parameter cannot be underestimated in defibrillator design since different pulse durations have different levels of safety.181COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPNão tem2011/51199-6; 2011/51199-6The authors are grateful to the R&D team at CEB/UNICAMP and NMCE-Núcleo de Medicina e Cirurgia Experimental at Faculty of Medical Science-UNICAMP for the valuable technical support. This study was supported by CAPES (Coordination of Improvement of Higher Education Personnel, in Portuguese, scholarship to Priscila C. Antoneli) and FAPESP (Foundation for Research of the State of São Paulo, in Portuguese, Proc. N 2011/51199-6). This study was supported by CAPES (Coordination of Improvement of Higher Education Personnel, in Portuguese, scholarship to Priscila C. Antoneli) and FAPESP (Foundation for Research of the State of São Paulo, in Portuguese, Proc. N 2011/51199-6