2,025 research outputs found
From Liberal Acceptance to Intolerance: Discourses on Sexual Diversity in Schools by Portuguese Young People
Purpose: This article explores different strands of educational discourse about sexual diversity in Portuguese schools, from the students’ perspectives.Method: The methodological approach consisted in conducting focus groups discussions: 36 with 232 young students (H = 106, M = 126) in 12 public secondary schools.Findings: Students reveal a polyphony of discourses that gravitate between liberal acceptance, conditional acceptance and intolerance.Research implications: Attention is drawn not only to discriminatory processes that question school as a democratic place for LGBT youth, but also to the gap between what is legally decreed and a lack of know-how in the approach to sexual diversity in school
The house of the little tooth Diniz : an oral health educational project
Dental caries is currently one of the major public health problems, given its high incidence among 6-12-year-old children. This age group of children is considered a priority group, due to the transitional period of the replacement of deciduous teeth. This article intends to present a ludic-pedagogical instrument for oral health education, targeted at these children, based on the learning of problems related to oral health through a story narrative and associated pictograms. By means of a health education manual with several pictorial representations of dentistry clinical acts, we intended to imagetically reinforce the therapeutic adherence of children to Paediatric Dentistry as well as oral health prevention care, which are considered determinant factors for oral health success amongst children. The choice of a handbook format for this purpose was considered a health education pedagogical strategy with added value to the Paediatric Dentistry appointment setting, granting patients an active and leading role in their therapeutic path. The handbook can also be of use to younger children, through parental storytelling, establishing a dyadic communication between parents, educators and professionals.info:eu-repo/semantics/publishedVersio
application in C-H activation catalysis
This work was supported by the Spanish Government, the Spanish National Research Council (CSIC).
We also thank Dr Martinez from Novozymes.
Publisher Copyright:
© 2023 RSC.The effect of the temperature in the synthesis of Pd nanoparticles in the metal-enzyme biohybrids is evaluated. The effect on the formation, size, and morphology of nanoparticles was evaluated using C. antarctica B lipase as the protein scaffold. XRD analyses confirmed the formation of crystalline Pd(0) as the metal species in all cases. TEM analyses revealed spherical crystalline nanoparticles with average diameter size from 2 nm at 4 °C synthesis to 10 nm obtained at 50 °C synthesis. The thermal phenomenon was also critical in the final hybrid formation using more complex enzymes, where the relation of the protein structure and temperature and the influence of the latter has been demonstrated to be critical in the reducing efficiency of the enzyme in the final Pd nanoparticle formation, in the metal species, or even in the final size of the nanoparticles. Different Pd biohybrids were evaluated as catalysts in the C-H activation of protected l-tryptophan under mild conditions. Pd@CALB4 showed the best results, with >99% conversion for C-2 arylation in methanol at room temperature with a TOF value of 64 min−1, being 2 or 4 times higher than that of the other synthesized hybrids. This catalyst showed a very high stability and recyclability, maintaining >95% activity after three cycles of use.publishersversionpublishe
Proton-coupled electron transfer mechanisms of the copper centres of nitrous oxide reductase from Marinobacter hydrocarbonoclasticus – An electrochemical study
PTDC/BBB-BQB/0129/2014,
FCT/MCTES, UID/Multi/04378/2019,
UID/QUI/50006/2019,
Centro de Quimica Estrutural multiannual funding 2020-2023,
UID/QUI/00100/2019.Reduction of N2O to N2 is catalysed by nitrous oxide reductase in the last step of the denitrification pathway. This multicopper enzyme has an electron transferring centre, CuA, and a tetranuclear copper-sulfide catalytic centre, “CuZ”, which exists as CuZ*(4Cu1S) or CuZ(4Cu2S). The redox behaviour of these metal centres in Marinobacter hydrocarbonoclasticus nitrous oxide reductase was investigated by potentiometry and for the first time by direct electrochemistry. The reduction potential of CuA and CuZ(4Cu2S) was estimated by potentiometry to be +275 ± 5 mV and +65 ± 5 mV vs SHE, respectively, at pH 7.6. A proton-coupled electron transfer mechanism governs CuZ(4Cu2S) reduction potential, due to the protonation/deprotonation of Lys397 with a pKox of 6.0 ± 0.1 and a pKred of 9.2 ± 0.1. The reduction potential of CuA, in enzyme samples with CuZ*(4Cu1S), is controlled by protonation of the coordinating histidine residues in a two-proton coupled electron transfer process. In the cyclic voltammograms, two redox pairs were identified corresponding to CuA and CuZ(4Cu2S), with no additional signals being detected that could be attributed to CuZ*(4Cu1S). However, an enhanced cathodic signal for the activated enzyme was observed under turnover conditions, which is explained by the binding of nitrous oxide to CuZ0(4Cu1S), an intermediate species in the catalytic cycle.authorsversionpublishe
Heterocellular Contacts with Mouse Brain Endothelial Cells Via Laminin and alpha 6 beta 1 Integrin Sustain Subventricular Zone (SVZ) Stem/Progenitor Cells Properties
Neurogenesis in the subventricular zone (SVZ) is regulated by diffusible factors and cell-cell contacts. In vivo, SVZ stem cells are associated with the abluminal surface of blood vessels and such interactions are thought to regulate their neurogenic capacity. SVZ neural stem cells (NSCs) have been described to contact endothelial-derived laminin via (01 integrin. To elucidate whether heterocellular contacts with brain endothelial cells (BEG) regulate SVZ cells neurogenic capacities, cocultures of SVZ neurospheres and primary BEG, both obtained from C57BL/6 mice, were performed. The involvement of laminin integrin interactions in SVZ homeostasis was tested in three ways. Firstly, SVZ cells were analyzed following incubation of BEC with the protein synthesis inhibitor cycloheximide (GHX) prior to coculture, a treatment expected to decrease membrane proteins. Secondly, SVZ cells were cocultured with BEG in the presence of an anti-alpha 6 integrin neutralizing antibody. Thirdly, BEC were cultured with beta 1(-/-) SVZ cells. We showed that contact with BEC supports, at least in part, proliferation and stemness of SVZ cells, as evaluated by the number of BrdU positive (+) and Sox2+ cells in contact with BEG. These effects are dependent on BEG-derived laminin binding to alpha 6 beta 1 integrin and are decreased in cocultures incubated with anti-alpha 6 integrin neutralizing antibody and in cocultures with SVZ beta 1(-/-) cells. Moreover, BEG-derived laminin sustains sternness in SVZ cell cultures via activation of the Notch and mTOR signaling pathways. Our results show that BEC/SVZ interactions involving alpha 6 beta 1 integrin binding to laminin, contribute to SVZ cell proliferation and stemness
Physical health of food consumers during the COVID-19 pandemic
The present research aims to analyze the habits observed in the perception of the general physical health condition of Portuguese food consumers in the COVID-19 pandemic. The investigation is focused on indicators such as weight, physical activity, and consumption habits through the adoption of healthy and not healthy food. Centered on a quantitative approach, the research is based on the application of a questionnaire to a sample of 741 Portuguese consumers, between November 2020 and February 2021, a period during which the most severe measures of social isolation were imposed by the Portuguese government, since the beginning of the pandemic. Moreover, the questionnaire was applied to consumers over 18 years old. According to this population, and considering a 95% confidence level and a margin of error of 4%, the sample has a minimum of 601 responses. Being so, the results of this research are representative for the Portuguese food consumers. The theoretical model was estimated using Partial Least Squares (PLS) in the Smart PLS 3.0 software. The obtained results allowed us to conclude that the Portuguese perception of their weight did not change in the pandemic, despite showing that in general, the pandemic had a negative impact on their physical condition. On the other hand, the results show that the Portuguese associate the practice of physical exercise with physical well-being. Respondents also confirm a positive relationship between “positive eating behaviors (such as consumption of fruits and vegetables, low saturated foods and rich in monounsaturated and polyunsaturated fats” and water consumption) and “the perception of physical health in general”. On the contrary, respondents’ perception of the choice of negative eating behaviors (measured by the consumption of products with a high content of salt and sugar, snacks, and processed frozen and pre-cooked foods) have a negative impact on the “assessment of physical health, in the COVID-19 pandemic”. Hence, it was concluded that the Portuguese consider that an eventual increase in weight does not necessarily correspond to a perception of worse physical health; the practice of physical exercise and good eating habits corresponds to a perception of better physical health; the adoption of bad eating habits corresponds to the perception of bad physical health.This work is supported by national funds, through the FCT-Portuguese Foundation for
Science and Technology under the project UIDB/04630/2020
Opening the “Black Box” of university entrepreneurial intention in the era of the COVID-19 pandemic
This research aims to study the determinants of entrepreneurial intention in academia and compare the outcomes from two different moments, before and during the COVID-19 pandemic. For this purpose, a quantitative methodology was used, whereby a questionnaire was given to higher education students in these two chronological moments. From the obtained results, it was possible to ascertain that, given the motivational dimension, the attitude towards behavior and perceived behavioral control are having a positive impact on entrepreneurial intentions during the pandemic and that subjective norms have a negative impact on entrepreneurial intentions. This relationship of influences is unchanged, either before or during the pandemic. Regarding the environmental dimension, both of the variables under analysis are having a negative impact on entrepreneurial intention during the pandemic period, which corresponds to an aggravation or loss of positive influences when compared to the context before the pandemic, and the next assessment had a positive impact on entrepreneurial intentions. On the theoretical contributions, the findings are very important, as they strengthen the literature on entrepreneurial intentions, and in specific contexts of social and economic instability. As for practical contributions, this research suggests actions to agents with an important intervention role in the community, one of these agents is Higher Education Institutions, which play a determining role by creating a positive environment to support their students’ entrepreneurial intent. This research is original, as far as we are informed, and it is the first to study entrepreneurial intention in academia during the COVID-19 pandemic in the Portuguese context. Moreover, we suggest that the obtained results should be succeeded by further studies to confirm the evolutionary trends now identified on the subject under analysis.This work was supported by the Foundation for Science and Technology “UIDB/04630/2020
Caracterização cinética e cinemática da marcha de indivíduos adultos obesos
O presente estudo apresenta a caracterização cinemática e cinética da marcha de indivíduos obesos. Envolveu instrumentos como Pedar-Novel, para recolha de dados da pressão plantar; Plataforma Bertec 4060-10, para dados de Força de Reacção ao Solo (FRS), Câmaras digitais Sony, 50Hz para ângulos do pé; IPAQ para dados de actividade física.
Foram seleccionados individuos com IMC≥30Kg/m2, para o grupo experimental e com IMC≤ 30Kg/m2 para o grupo controlo.
Os resultados mostraram pelos valores de FRS e respectivos tempos de ocorrência que indivíduos obesos, quando comparados com indivíduos eutróficos, exercem forças superiores ocasionando uma sobrecarga mecânica ao nível do sistema músculo-esquelético.This study presents the characterization of gait kinematics and kinetics of obese individuals. Instruments involved as Novel Pedar to collect plantar pressure data; Platform BERTEC 4060-10, data for the Ground Reaction Force (GRF), Sony digital cameras, 50Hz angles to the foot; IPAQ data for physical activity.
We selected individuals with a BMI ≥ 30Kg/m2 for the experimental group and a BMI ≤ 30Kg/m2 for the control group. The results showed the values of GRF and their times of occurrence that obese individuals compared with normal individuals have superior forces causing a mechanical overload at the level of the musculoskeletal system
Evaluation of the influence of the formalin fixation time on the elemental content of tissues measured with X-ray fluorescence
Funding Information:
This work was partially supported by the research centre grant UID/FIS/04559/2021 to LIBPhys-UNL from the FCT/MCTES/PIDDAC , Portugal.
Publisher Copyright:
© 2023 The AuthorsOne of the most widely used methods for tissue preservation and fixative during transportation is the conservation in formalin during variable amounts of time. In this study, we have evaluated the influence of formalin fixation time in the elemental composition of human tissue samples using Energy Dispersive X-Ray Fluorescence (EDXRF). Ten sets of human tissue samples (from colon, ileum, stomach, and spleen) were exposed to different formalin fixation times, between 2 and 24 days, and for each tissue, the elemental content throughout time was compared to the elemental content of the snap-frozen sample of the same tissue that was not exposed to formalin. Additionally, in order to further evaluate the transference of elements, the formalin solution was also analysed using EDXRF. Our results showed a clear decrease of Cl and K in the tissues, transferred to the formalin solution. Conversely, there is an uptake of P in the tissue, likely due to the buffered formalin solution. The consistent alterations seen in the studied elements across all the ten different tissues allow us to hypothesize that in the future, there will be different thresholds for their use as diagnostic tools in unfixed (intraoperative exams) as well as formalin fixed paraffin embedded tissues.publishersversionpublishe
Torque-assisting Compressed Air Energy Storage Hydraulic Wind Drivetrains
In this paper, Compressed Air Energy Storage (CAES) as a popular technology for wind energy storage, is mathematically integrated with a hydraulic wind power system. Hydraulic machinery as prime-movers is utilized to gain the benefit of eliminating costly and heavy gearboxes. The goal of this work is to improve the power delivery performance while maintaining a stable frequency generation in a 600kW hydraulic wind power system. Simulation results demonstrate that the integration of compressed air energy storage has improved the quality of power delivery such that the maximum power demand can be delivered while maintaining the frequency under variable wind speeds
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