Oxidative stress responses and cellular energy allocation changes in microalgae following exposure to widely used human antibiotics

The individual effect of four human antibiotics on the microalgae Raphidocelis subcapitata was investigated following a 120-h exposure. The effects were assessed by analyzing growth, and biochemical parameters related with: 1) antioxidant capacity and oxidative damage by measuring superoxide dismutase (SOD) activity and lipid peroxidation (LPO) levels; and 2) cellular energy allocation (CEA) by quantifying the content in energy reserves, which represents the energy available (Ea), and the electron transport system activity that represents a measure of oxygen and cellular energy consumption (Ec). Growth yield inhibitory concentrations of sulfamethoxazole (18-30%), clarithromycin (28.7%), ciprofloxacin (28%) and erythromycin (17-39%) were found to elicit a considerable increase in Ec, thereby causing a significant decrease in the CEA. The elevated Ec can be a result of the need to respond to oxidative stress occurring under those conditions given the significant increase in SOD activity at these levels. For sulfamethoxazole, erythromycin and ciprofloxacin, the antioxidant responses do not seem to be enough to cope with the reactive oxygen species and prevent oxidative damage, given the elevated LPO levels observed. A stimulatory effect on growth yield was observed (up to 16%) at ciprofloxacin lowest concentration, which highly correlated with the increase in CEA. Based on the no observed effect concentration (NOECs) and/or effective concentration (EC10) results, Ec, SOD and CEA were more sensitive than the classical endpoint of growth rate for all the tested antibiotics. By revealing the antibiotic stress effects in R. subcapitata at the cellular level, this study suggests CEA as a more reliable indicator of the organisms' physiological status.info:eu-repo/semantics/publishedVersio

Castanea sativa shells and fruits: Compositional analysis by proton induced X-ray emission

Chestnut fruits, from Castanea sativa Miller species, have been previously characterized mainly to study the nutritional and biochemical parameters, with mineral contents receiving less attention from the researchers, although these minerals are essential for several mechanisms in human body. In this study, a detailed elemental compositional analysis was performed using Proton Induced X-ray Emission (PIXE) to characterize two varieties of Castanea sativa Miller chestnuts (Longal and Judia). This study comprises the composition of the outer shells (pericarp), inner shells (episperm) and the edible fruits. From our knowledge, this is the first time that the presence of up to 20 elements on the shells and the fruits are reported. Furthermore, by PIXE it was possible to quantify them, allowing significant improvements in the assessment of chestnuts composition. Essential and nonessential elements were quantified on a food item that is used mainly for human consumption but it is also incorporated in animal feeding.Authors acknowledge R. Pinheiro for sample preparation. This work was developed within the Coordinated Research Project D61024 ‘‘Development of New Applications of Machine Generated Food Irradiation Technologies’’ financed by the International Atomic Energy Agency (IAEA). IST authors gratefully acknowledge the FCT (Fundação para a Ciência e a Tecnologia) support through the UID/Multi/04349/ 2013 and UID/FIS/50010/2013 projects.info:eu-repo/semantics/publishedVersio

Application of eye-tracking technology for the evaluation of different packaging designs for premium organic herbal teas

The main goal of this study was to assess the impact four graphic designs (figure 1) on the perception of different extrinsic characteristics (premium and organic denomination, infusion name and brand).info:eu-repo/semantics/publishedVersio

Considering the stiffness of the forming tools in the numerical analysis of the ironing process

Ironing can occur in cylindrical cup drawing whenever the thickness of the drawn flange is larger than the gap between the punch and the die. This is particularly relevant for materials that present r-values lower than 1.0, such as the aluminium alloys, since they tend to present more thickening of the flange. The aim of this study is to evaluate numerically the impact of the elastic deformation of the forming tools on the final cup geometry, i.e., the earing profile and the evolution of thickness along the circumferential direction, at different heights. Different contact conditions are also analysed since they strongly affect both the thickness strain and the earing profile. The process conditions considered are the ones from EXACT, the ESAFORM Benchmark 2021, enabling the comparison with experimental results. Considering the deformation of the forming tools mainly impacts the ironing stage, enabling predicting wall thickness values larger than the gap between the punch and the die.The authors gratefully acknowledge the financial support of the Portuguese Foundation for Science and Technology (FCT) under projects with reference 2022.08459.PTDC, UIDB/00285/2020 and LA/P/0112/2020

In-depth inhomogeneities in CIGS solar cells: identifying regions for performance limitations by PIXE and EBS

When considering materials to be used as active layers in solar cells, an important required parameter is the proper knowledge of their elemental composition. It should be heavily controlled during growth in order to obtain the desired bandgap and to decrease recombination defects and then increase the solar cell electrical performance. Ion beam analytical techniques and, in particular particle-induced X-ray emission (PIXE) and elastic backscattering spectrometry (EBS), are quite suitable to determine the thickness and composition of such active layers. Furthermore, if these techniques are performed using a nuclear microprobe, lateral and in-depth inhomogeneities can be clearly observed from 2D maps. In many cases, composition variations can be detected from the classical 2D maps obtained from the PIXE spectra. In this work, it is shown how the in-depth variations can also be studied when considering 2D maps reconstructed from the EBS spectra. Such variations are derived from processing conditions and can be related to: i) composition, ii) thickness, iii) roughness, iv) other non-trivial issues. Examples obtained on Cu(In,Ga)Se2 based cells are presented and discussed. Furthermore, the combination of ion beam analytical techniques such as PIXE and EBS is shown to be a competitive and alternative method to those more used and established techniques such as X-ray fluorescence for checking the average composition of the solar cells active layers or SIMS for the determination of elemental depth profile.publishe

ACTIVE DRAG AND PHYSICAL CHARACTERISTICS IN AGE GROUP SWIMMERS

The purpose of this study was to identify the influence of body size and morphology in active drag (Da) in front crawl swimming. Seventeen male national level swimmers (age: 15.42 ± 0.53 years, height: 178.52 ± 7.42 cm, body mass: 66.82 ± 7.45 kg) were selected from a large pool (350) of swimmers evaluated using the velocity perturbation method. Inclusion criterion was having achieved the same maximal velocity in the test (1.78 m.s-1). Hydrodynamic variables showed large variation and were correlated to body mass and height. Height corrected for the squared body mass showed a strong negative association with Da (-0.810). Swimmers of equivalent performance level have different active hydrodynamic profiles, according to body size and morphological characteristics

Assessing the influence of long-chain fatty acids on aerobic granular sludge stability in a sequencing batch reactor

The presence of long-chain fatty acids (LCFA) in biological wastewater treatment systems can cause various operational issues. This study evaluated the effect of LCFA, at typical concentrations found in domestic wastewater, on the performance and stability of aerobic granular sludge (AGS) in a sequencing batch reactor. At an oleate concentration of 61 ± 2 mg L-1, oleate started to accumulate in the reactor, resulting in an increase of volatile suspended solids concentration in the effluent. This caused small granules to be washed out due to their larger specific surface area for oleate adsorption. Selecting large granules could minimize oleate adsorption, preventing sludge washout and maintaining the reactor stability. Overall, the study demonstrates the feasibility of using AGS systems for treatment of oleate-containing wastewater for concentrations below 61 ± 2 mg L-1 and highlights the importance of limiting oleate adsorption for the stability of AGS systems.The authors thank the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit, and by LABBELS – Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, LA/P/0029/2020. The authors also acknowledge the financial support to Sérgio A. Silva through the grant SFRH/BD/122623/2016 and COVID/BD/151748/2021 provided by FCT. Daniela P. Mesquita acknowledges FCT funding under DL57/2016 Transitory Norm Programme.info:eu-repo/semantics/publishedVersio

Cistus ladanifer as a Potential Feedstock for Biorefineries: A Review

ABSTRACT: Cistus ladanifer (rockrose) is a widespread shrub species in the Mediterranean region well known due to its production of labdanum gum, especially in the hot season. Its leaves and branches can be subjected to different extraction and distillation processes to produce various types of extracts. The natural extracts of C. ladanifer have several applications, especially in the perfumery and cosmetics sector. C. ladanifer extracts, in addition to presenting interesting odoriferous properties, are also known for their bioactive properties, such as antioxidant and antimicrobial. Use of this species in animal feed or phytostabilisation of mining areas has also been successfully applied. On the other hand, the lignin and polysaccharides that are the major fractions from Cistus residues can be relevant sources of high-value products in a biorefinery framework. Recently, it has been reported that the residues obtained from the essential oil industry can sustain production of significant amounts of other marketable products, namely phenolic compounds, oligomeric and monomeric sugars, lignin, and lactic acid. All these applications show the potential of C. ladanifer as a raw material to be fully valued in a biorefinery context, contributing to important revenues and generating an associated marketable biobased product portfolio.info:eu-repo/semantics/publishedVersio

On the effect of the ratio between the yield stresses in shear and in uniaxial tension on forming of isotropic materials

It is generally believed that the choice of the yield criterion used to describe the plastic behaviour of isotropic metallic materials does not affect much the accuracy of the predictions of forming operations. For this reason, the von Mises yield criterion is used for modelling the plastic behaviour. However, according to the von Mises yield criterion, irrespective of the material, the ratio between the yield stresses in simple shear and in uniaxial tension is the same. In this paper, it is presented a numerical study which reveals that even for one of the simplest deep drawing processes, namely the forming of a cylindrical cup, the yielding description influences the predictions of the plastic strains and the final profile of the part. For the description of yielding, an isotropic yield criterion which allows to differentiate between isotropic materials was used. Specifically, this yield criterion involves a parameter α which is expressible solely in terms of the ratio between the yield stresses in shear and in uniaxial tension; for α = 0 it reduces to the von Mises yield criterion. The results of the numerical study are revealing and are believed to provide a new point of view when considering material requirements for drawing performance and models to be used for prediction of the plastic behaviour in deep-drawing processes. From the analysis of the loading paths that the materials experience during the forming of the cup, it appears that the prevalent belief that the yielding properties in the tension-tension quadrant of the yield surface dictate the final profile should be reconsidered. Indeed, the simulations results indicate that for isotropic materials characterized by α > 0 (σT/τY> √ 3), the cup height is greater than for a von Mises material (α = 0), which is higher than the one obtained for materials with α < 0 (σT/τY< √ 3), i.e. lower values of the ratio between the yield stresses in shear and in uniaxial tension lead to greater cup heights. It is shown that this is mainly related to the plastic deformation of the material initially located in the flange region, which is dictated by the shape of the yield surface in the compression-tension quadrant (i.e. normal to the yield surface in the region between uniaxial compression and pure shear stress states).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 (POCI01–0145-FEDER-030592) and PTDC/EME-EME/31243/2017 (POCI01–0145-FEDER-031243) and by UE/FEDER through the program COMPETE2020 under the project MATIS (CENTRO-01–0145-FEDER000014) and UIDB/00285/2020. JLA and NC gratefully acknowledge partial support for this work from the Air Force Research Laboratory (AFRL) under contract FA8651–08-D-0108/52