Ultrasonic Fatigue Analysis on Steel Specimen with Temperature Control : Evaluation of Variable Temperature Effect

Non peer reviewe

Fish communities in the lower Tagus inland wetlands: from anthropogenic pressures to conservation management

Inland wetlands are important biodiversity hotspots and amongst the most impacted ecosystems worldwide. Conservation management and restauration actions in wetlands are thus urgently needed to reverse trends in species loss and habitat degradation, particularly in regions harbouring already endangered endemic species. Inland wetlands may play an important role in supporting endemic endangered fishes in the Lower Tagus basin, where anthropogenic pressures have been increasing, but there is a lack of studies on fish communities, and few areas are identified as inland wetlands. Here, we aim to identify small inland wetlands in the Lower Tagus River and their potential role in supporting fish species, constituting the first study to identify and evaluate the most important fish communities. Inland wetlands were identified through the usage of remote sensing techniques and the calculation of a Normalized Difference Water Index (NDWI) with Sentinel-2 imagery for the Lower Tagus region. From a total of 486 locations identified, 31 were recognized as wetlands as having potential to host fish communities, with 11 being selected for sampling after in loco assessment. Fish sampling was conducted between 6 May and 11 June 2021. Furthermore, for each wetland, we evaluated anthropogenic stressors and land use changes between 2007 and 2018, using national land use data (i.e., Carta de Uso e Ocupação do Solo). A total of 7727 fishes from eight non-native and five native species were captured. Overall, fish communities were dominated by non-native species (97% catches), but both European eel (Anguilla anguilla) and Lisbon arched-mouth nase (Iberochondrostoma olisiponense), which are globally classified as critically endangered (CR), were found in at least two wetlands. Our results suggest that, over the last 10 years, intensive agriculture decreased (on average ≈ 3%) in the areas surrounding these wetlands, being replaced by extensive agriculture or natural uses. Despite non-native fish prevalence, some wetlands may act as refuge habitats for CR fish species. These results are important for guiding the restoration of inland wetlands and promoting conservation management actions to help reverse fish diversity loss.info:eu-repo/semantics/publishedVersio

Neural stem cells and cannabinoids in the spotlight as potential therapy for epilepsy

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).Epilepsy is one of the most common brain diseases worldwide, having a huge burden in society. The main hallmark of epilepsy is the occurrence of spontaneous recurrent seizures, having a tremendous impact on the lives of the patients and of their relatives. Currently, the therapeutic strategies are mostly based on the use of antiepileptic drugs, and because several types of epilepsies are of unknown origin, a high percentage of patients are resistant to the available pharmacotherapy, continuing to experience seizures overtime. Therefore, the search for new drugs and therapeutic targets is highly important. One key aspect to be targeted is the aberrant adult hippocampal neurogenesis (AHN) derived from Neural Stem Cells (NSCs). Indeed, targeting seizure-induced AHN may reduce recurrent seizures and shed some light on the mechanisms of disease. The endocannabinoid system is a known modulator of AHN, and due to the known endogenous antiepileptic properties, it is an interesting candidate for the generation of new antiepileptic drugs. However, further studies and clinical trials are required to investigate the putative mechanisms by which cannabinoids can be used to treat epilepsy. In this manuscript, we will review how cannabinoid-induced modulation of NSCs may promote neural plasticity and whether these drugs can be used as putative antiepileptic treatment.This work was supported by IF/01227/2015 and UID/BIM/50005/2019, projeto financiado pela Fundação para a Ciência e a Tecnologia (FCT)/Ministério da Ciência, Tecnologia e Ensino Superior (MCTES) através de Fundos do Orçamento de Estado. D.M.L. (PD/BD/141784/2018) and L.R.-R. (PD/BD/150344/2019) were in receipt of a fellowship from FCT. The authors are in hold of a H2020 Twinning Action from EU (EpiEpiNet).info:eu-repo/semantics/publishedVersio

Reversed-phase chromatographic separation and downstream precipitation of lupane- and oleanane-type triterpenoids: experiments and modeling based on the method of moments

The reversed-phase chromatographic separation of two triterpenic acids (TTAs), betulinic and oleanolic acids, using a triacontyl (C30) stationary phase was addressed in this work. Methanol, water, acetonitrile, ethanol, isopropanol, ethyl acetate, acetone and mixtures thereof were tested, and the best mobile phase to conduct the separation was found to be methanol/acetonitrile 50/50 (%, v/v) at 23 °C, taking into account parameters like selectivity, resolution and TTAs solubility. The method of moments was used to determine the equilibrium constants of isotherms, the axial dispersion coefficients and the global linear driving force coefficients of pure betulinic and pure oleanolic acids. These parameters were then successfully validated by modeling unary and binary breakthrough curves. Simulated moving bed calculations showed that betulinic and oleanolic acids can be both obtained with purity of 99.2 % and productivity of 56.2 kg/(m3adsorbent day) using the packing material of an Acclaim C30 column with a 1-1-1-1 configuration with columns of 7.5 cm long. Finally, in order to recover the two TTAs from the SMB extract and raffinate streams, water was envisioned as a precipitation agent. Accordingly, the solubility of each TTA was measured in methanol/acetonitrile 70/30, 50/50, and 30/70 (%, v/v) modified with water. The obtained results showed that adding 65 % (%, v/v) of water it is possible to precipitate 98 % of the dissolved TTAs in all the tested methanol/acetonitrile mixtures.publishe

Historical food-web changes in invaded fish communities in the lower Guadiana basin

Freshwater ecosystems are increasingly being reshaped by biological invasions, leading to biotic homogenization and biodiversity loss. However, the extent to which novel species may drive changes in food-web structure over time remains poorly understood. Clarifying changes in historical ecological processes is critical to inform conservation and restoration efforts in recipient ecosystems. Here, we address food-web changes associated with fish invasions in the Lower Guadiana Basin (LGB) over the past 40 years, by contrasting feeding relationships between museum-archived and contemporary specimens, using stable carbon (δ13C) and nitrogen (δ15N) ratios. Specifically, trophic niches of museum-archived fishes sampled throughout 1978–1987 and 1999–2004 corresponding to the initial establishment and spread of non-native fishes, respectively, were compared with those of fishes sampled in 2019, characterizing the integration of non-native species in the recipient ecosystem. We focused on five native species (Anaecypris hispanica, Cobitis paludica, Iberochondrostoma lemmingii, Squalius pyrenaicus and Squalius alburnoides) and four non-native species (Lepomis gibbosus, Australo heros facetus, Micropterus salmoides and Gambusia holbrooki) with potential to cover multiple trophic positions in the food-webs. We approached historical baseline resources using prey items in gut con tents of the museum-archived fishes and characterized primary producers and macroinvertebrates in 2019. Prior to analysis, samples were normalized for high lipid content and corrected for preservation. We found considerable asymmetries in niche partitioning among species as invasion progressed. Over time, native species tended to be displaced to lower trophic levels, while non-native species showed significantly higher trophic niches, driven mainly by increases in trophic (δ15N) range. Our study highlights that stable isotopes may provide important insights on historical food-web structure and particularly on processes underpinning ecological changes associated with anthropogenetic pressures on freshwater ecosystems.info:eu-repo/semantics/publishedVersio

Railway bridge geometry assessment supported by cutting-edge reality capture technologies and 3D as-designed models

Documentation of structural visual inspections is necessary for its monitoring, maintenance, and decision about its rehabilitation, and structural strengthening. In recent times, close-range photogrammetry (CRP) based on unmanned aerial vehicles (UAVs) and terrestrial laser scanners (TLS) have greatly improved the survey phase. These technologies can be used independently or in combination to provide a 3D as-is image-based model of the railway bridge. In this study, TLS captured the side and bottom sections of the deck, while the CRP-based UAV captured the side and top sections of the deck, and the track. The combination of post-processing techniques enabled the merging of TLS and CRP models, resulting in the creation of an accurate 3D representation of the complete railway bridge deck. Additionally, a 3D as-designed model was developed based on the design plans of the bridge. The as-designed model is compared to the as-is model through a 3D digital registration. The comparison allows the detection of dimensional deviation and surface alignments. The results reveal slight deviations in the structural dimension with a global average value of 9 mm.The authors would like to thank the financial support from: Base Funding—UIDB/04708/ 2020 and Programmatic Funding—UIDP/04708/2020 of the CONSTRUCT—“Instituto de I&D em Estruturas e Construções, as well as ISISE (UIDB/04029/2020) and ARISE (LA/P/0112/2020)”—funded by national funds through the FCT/MCTES (PIDDAC). Additionally, the support by the doctoral grant UI/BD/150970/2021 (to Rafael Cabral)—Portuguese Science Foundation, FCT/MCTES. Furthermore, this work is framed within the project “Intelligent structural condition assessment of existing steel railway bridges” financed by the bilateral agreement FCT-NAWA (2022-23), as well as project “FERROVIA 4.0”, with reference to POCI-01-0247-FEDER-046111, co-funded by the European Regional Development Fund (ERDF), through the Operational Program for Competitiveness and Internationalization (COMPETE 2020) and the Lisbon Regional Operational Program (LISBOA 2020), under the PORTUGAL 2020 Partnership Agreement, as well as “NEXUS: Innovation Pact Digital and Green Transition—Transports, Logistics and Mobility”, nr. C645112083-00000059, investment project nr. 53, financed by the Recovery and Resilience Plan (PRR) and by European Union—NextGeneration EU

Identification of a novel deletion in SURF1 gene: Heterogeneity in Leigh syndrome with COX deficiency

Leigh syndrome (LS) is a rare, progressive neurodegenerative mitochondrial disorder of infancy. It is a genetically heterogeneous disease. The mutations in SURF1 gene are the most frequently known cause. Here two cases of LS likely caused by SURF1 gene variants are reported: a 39-year-old male patient with a novel homozygous deletion (c.-11_13del), and a case of a 6-year-old boy with the same deletion and a nonsense mutation (c.868dupT), both in heterozygosity. Blue native PAGE showed absence of assembled complex IV. This is the first report of a variant that may abolish the SURF1 gene initiation codon in two LS patients.info:eu-repo/semantics/publishedVersio

Biodegradation of mono-, di- and trifluoroacetate by microbial cultures with different origins

This work focused on the biodegradation of three structurally related fluoroacetates (FAs), mono- (MFA), di- (DFA) and trifluoroacetate (TFA), using as microbial inocula samples collected from a site with a long history of industrial contamination and activated sludge obtained from a municipal wastewater treatment plant. Biodegradation experiments were carried out under different modes of substrate supplementation, which included (i) FAs fed as sole carbon sources; (ii) FAs (only for DFA and TFA) fed in co-metabolism with sodium acetate; and (iii) mixtures of MFA with DFA or TFA. Biodegradation of the target compounds was assessed through fluoride ion release. Defluorination was obtained in the cultures fed with MFA, while DFA and TFA were recalcitrant in all tested conditions. When present in mixture, DFA was shown to inhibit biodegradation of MFA, while TFA had no effect. A total of 13 bacterial isolates obtained from MFA degrading cultures were found to degrade 20mgL-1 of this compound, as single strains, when supplemented as a sole carbon source. Sequencing of the 16S rRNA gene indicated that among these degrading bacteria only Delftia acidovorans had been previously reported to be able to degrade MFA. This work shows that, despite their similar chemical structures, biodegradation of the three tested FAs is very distinct and draws attention to the unknown impacts that the accumulation of DFA and TFA may have in the environment as a result of their high recalcitrance.info:eu-repo/semantics/publishedVersio

Ensinar através da modelação matemática : uma primeira discussão baseada numa experiência de ensino no 4º ano de escolaridade

A modelação matemática como ambiente de aprendizagem é, atualmente, considerada uma metodologia que se fundamenta na conjugação da resolução de problemas com referência na realidade envolvente. A sua implementação na sala de aula permite que os alunos assumam um papel de relevo na enunciação de tais situações baseadas na resolução de problemas e na busca da(s) sua(s) solução(ões) sendo, também por isso, encarada como uma das formas de potenciar aprendizagens matemáticas significativas, participando os alunos ativamente no processo e sendo (co)responsáveis pelo conhecimento do grupo através da partilha e discussão sistemática das soluções encontradas. Para uma plena aplicação da modelação matemática como ambiente de aprendizagem o conhecimento do professor assume um lugar de destaque, não só no que concerne à metodologia em si mas também relativamente aos temas matemáticos e suas possíveis conexões. Neste texto iremos apresentar uma experiência de modelação matemática como ambiente de aprendizagem realizada no 1.º Ciclo do Ensino Básico, à volta de uma tarefa envolvendo sequências.info:eu-repo/semantics/publishedVersio

Análise crítica da reconstrução da raiz da aorta com a preservação da valva aórtica: 11 anos de seguimento

INTRODUCTION: The composite mechanical valve conduit replacement is the standardized operation for aneurysms of the aortic root. The objective of this study is to evaluate the long-term surgical results of aortic valve-preserving procedures to the root reconstruction. METHODS: From 1996 to 2008, 54 consecutive patients underwent two different techniques of valve-sparing aortic root operation (40 Yacoub operations and 14 David operations). Mean age was 48 ± 14 years (range 17 to 74). 36 patients (66.7%) were male and 16 (29.6%) experienced Marfan's syndrome. The mean Euroscore was 4 ± 1.25. The mean follow up time was 4.1 years (from 49 days to 10.9 years). Clinical and echocardiographic parameters were analysed. T-Student paired test, the McNemar Non Parametric test and the Kaplan-Meyer Outcome Curves have been used. RESULTS: The hospital mortality was 5.6% and the average hospitalization time was 9±4 days. One non related late death (2%) was reported. The actuarial survival and freedom from reoperation were respectively 94.4% and 96% within 11 years of follow-up. There were benefits in reduction of functional class (P=0.002; 78% CF I), in reduction of aortic regurgitation (P<0.001; 78% with or without discrete reflux), in reduction of systolic and diastolic diameters, end-sytolic and end-diastolic volumes of left ventricle (respectively P=0.004; P<0.0001; P=0.036 and P<0.001). Two (3.9%) patients required aortic valve replacement due to severe aortic regurgitation during this same period. No thromboembolic, endocarditis or bleeding events were reported during the follow-up. CONCLUSION: The valve-sparing operation for aortic root aneurysms is an effective alternative to the use of a mechanical valve conduit replacement.INTRODUÇÃO: A utilização do tubo valvulado é a operação clássica para a reconstrução da raiz da aorta. O objetivo deste trabalho é avaliar a reconstrução da aorta ascendente com a preservação da valva aórtica. MÉTODOS: Entre 1996 e 2008, 54 pacientes consecutivos (66,7% do sexo masculino), com idade média de 48 ± 14 anos, foram submetidos à reconstrução da aorta ascendente e preservação da valva aórtica (40 remodelamentos e 14 reimplantes). O Euroscore médio foi de 4 ± 1,25 e 29,6% eram portadores de síndrome de Marfan. O tempo médio de seguimento foi de 4,1 anos (49 dias até 10,9 anos). Foram avaliados por parâmetros clínicos e ecocardiográficos. Para a análise dos dados foram utilizados os testes t de Student pareado, o não-paramétrico de McNemar e a curva de sobrevida de Kaplan-Meyer. RESULTADOS: A mortalidade hospitalar foi de 5,6%. O tempo médio de internação foi de 9 ± 4 dias. Houve um óbito tardio não relacionado (2%). A sobrevida e sobrevida livre de reoperação nos 11 anos de seguimento foram respectivamente de 94,4% e 96%. Houve melhora da classe funcional (P=0,002) (78% CF I), redução da insuficiência aórtica (P<0,001) (78% sem ou com refluxo discreto), redução dos diâmetros sistólico e diastólico, dos volumes sistólico final e diastólico final do ventrículo esquerdo, respectivamente P=0,004; P<0,001; P=0,036 e P<0,001. Dois pacientes foram submetidos à troca de valva aórtica (3,9%) com 4 e 10 anos da operação. Não foram observados fenômenos tromboembólicos, hemorrágicos ou endocardite durante o seguimento. CONCLUSÃO: A reconstrução da raiz da aorta com a preservação da valva aórtica é uma alternativa eficaz ao uso do tubo valvulado