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1.
Healthcare (Basel) ; 11(14)2023 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-37510539

RESUMO

A negative school climate resulting from homophobic and transphobic bias and discrimination is associated with poor well-being and mental health among LGBTQ+ youth. However, protective factors and mechanisms may buffer against the impact of stigmatization. Drawing on the socio-ecological model, minority stress theory, and positive youth development and agency perspectives, we carried out a systematic review of research focusing on factors that can promote the well-being of LGBTQ+ students in educational settings, outlining the primary outcomes from studies published between 2012 and 2022. The PRISMA protocol was used for this review, and 64 articles were scrutinized. The results of the thematic analysis revealed that both external factors (school-inclusive policies and extracurricular activities; social support from school, family, and the community; and school connectedness) and internal factors (psychosocial characteristics and personal agency) promote positive school experiences, such as the exploration of sexual and gender identities in a safe environment. The present findings highlight the need for inclusive school policies and strategies and individual-level interventions that target the well-being and positive mental health outcomes of sexual and gender minority students.

2.
Sensors (Basel) ; 21(23)2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34884119

RESUMO

In this paper, a metamaterial-inspired flat beamsteering antenna for 5G applications is presented. The antenna, designed to operate in the 3.6 GHz at 5G frequency bands, presents an unique flat form factor which allows easy deployment and low visual impact in 5G dense scenarios. The antenna presents a multi-layer structure where a metamaterial inspired transmitarray enables the two-dimensional (2D) beamsteering, and an array of microstrip patch antennas is used as RF source. The use of metamaterials in antenna beamsteering allows the reduction of costly and complex phase-shifter networks by using discrete capacitor diodes to control the transmission phase-shifting and subsequently, the direction of the steering. According to simulations, the proposed antenna presents steering range up to ±20∘, achievable in both elevation and azimuth planes, independently. To prove the concept, a prototype of the antenna has been built and experimentally characterised inside an anechoic chamber. Although constructed in a different substrate (FR4 substrate) as initially designed, beamsteering ranges up to 8∘ in azimuth and 13∘ in elevation, limited to the proposed case-studies, are reported with the prototype, validating the antenna and the usefulness of the proposed design.

3.
Sensors (Basel) ; 21(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34372397

RESUMO

Intelligent approaches in sports using IoT devices to gather data, attempting to optimize athlete's training and performance, are cutting edge research. Synergies between recent wearable hardware and wireless communication strategies, together with the advances in intelligent algorithms, which are able to perform online pattern recognition and classification with seamless results, are at the front line of high-performance sports coaching. In this work, an intelligent data analytics system for swimmer performance is proposed. The system includes (i) pre-processing of raw signals; (ii) feature representation of wearable sensors and biosensors; (iii) online recognition of the swimming style and turns; and (iv) post-analysis of the performance for coaching decision support, including stroke counting and average speed. The system is supported by wearable inertial (AHRS) and biosensors (heart rate and pulse oximetry) placed on a swimmer's body. Radio-frequency links are employed to communicate with the heart rate sensor and the station in the vicinity of the swimming pool, where analytics is carried out. Experiments were carried out in a real training setup, including 10 athletes aged 15 to 17 years. This scenario resulted in a set of circa 8000 samples. The experimental results show that the proposed system for intelligent swimming analytics with wearable sensors effectively yields immediate feedback to coaches and swimmers based on real-time data analysis. The best result was achieved with a Random Forest classifier with a macro-averaged F1 of 95.02%. The benefit of the proposed framework was demonstrated by effectively supporting coaches while monitoring the training of several swimmers.


Assuntos
Desempenho Atlético , Técnicas Biossensoriais , Dispositivos Eletrônicos Vestíveis , Atletas , Humanos , Natação
4.
Crit Rev Food Sci Nutr ; 61(22): 3904-3935, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32838560

RESUMO

The world's seafood supply and trade have increased in the last decades, as well as the potential for marketed species substitution. Currently, seafood safety and authenticity assessment have become central issues, directly related with the identification of improper labeling of processed foods. To detect and prevent mislabeling issues, species identification using DNA barcodes has been widely used as effective molecular markers. Therefore, this review intends to present the current status on the application of DNA barcodes to seafood species authentication. In this regard, the barcode regions, reference databases and related methodologies are described, while applications are listed and summarized. Cytochrome c oxidase subunit I (COI) gene has been the preferential targeted DNA region in animal species identification, including fish and shellfish, though other mitochondrial (cytb, 12S rRNA, 16S rRNA) and nuclear genes have been used. DNA barcoding relying on Sanger's sequencing has been the most used approach for seafood authentication. Nevertheless, in recent years, noteworthy progresses have been advanced toward DNA barcoding strategies, involving next generation sequencing. Methods relying on real-time PCR using species-specific primers and probes or followed by high resolution melting analysis combined with DNA barcodes represent alternative and promising approaches for simple, cost-effective and high-throughput species discrimination in processed seafood. Still, polymerase chain reaction with restriction fragment length polymorphism detection, targeting DNA barcodes, continues to be a well-established and broadly accepted method in seafood authentication.


Assuntos
Código de Barras de DNA Taxonômico , Alimentos Marinhos , Animais , RNA Ribossômico 16S , Reação em Cadeia da Polimerase em Tempo Real , Alimentos Marinhos/análise , Especificidade da Espécie
5.
Front Psychol ; 10: 2936, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32010018

RESUMO

Portugal is one of the most egalitarian countries in Europe in terms of lesbian, gay, bisexual, transgender, and intersex (LGBTI) individuals' legal rights. However, regarding education Portugal still lacks specific policies, plans and interventions to protect LGBTI students. To assess the perceptions of self-identified LGBTI youth regarding their school context, a total of 663 participants (aged from 15 to 20 years old) filled in an on-line questionnaire about their school climate. One hundred and forty-six of them answered an open-ended question about their personal experiences. A thematic analysis of these answers was conducted, and four main categories were identified: (i) victimization, (ii) coming out experiences, (iii) support networks, and (iv) demands. Most participants reported experiences of discrimination, and several sources of prejudice were identified. Furthermore, participants also recognized a lack of LGBTI information in school curriculum and made several demands. Besides inclusive laws, we suggest that the safety and the well-being of LGBTI youths in Portuguese schools depend upon others measures, such as teacher and school staff training, curricula inclusive of LGBTI diversity, and local strategies, such as Gay-Straight Alliances.

6.
Food Chem ; 245: 1034-1041, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29287319

RESUMO

Fish is one of the most common allergenic foods that should be accurately labelled to protect the health of allergic consumers. In this work, two real-time PCR systems based on the EvaGreen dye and a TaqMan probe are proposed and compared. New primers were designed to target the 16S rRNA gene, as a universal maker for fish detection, with fully demonstrated specificity for a wide range of fish species. Both systems showed similar absolute sensitivities, down to 0.01 pg of fish DNA, and adequate real-time PCR performance parameters. The probe system showed higher relative sensitivity and dynamic range (0.0001-50%) than the EvaGreen (0.05-50%). They were both precise, but trueness was compromised at the highest tested level with the EvaGreen assay. Therefore, both systems were successful, although the probe one exhibited the best performance. Its application to verify labelling compliance of foodstuffs suggested a high level of mislabelling and/or fraudulent practices.


Assuntos
Peixes/genética , Peixes/imunologia , Hipersensibilidade Alimentar/imunologia , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Sensibilidade e Especificidade
7.
Food Chem ; 230: 49-57, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28407939

RESUMO

This work aimed to exploit the use of DNA mini-barcodes combined with high resolution melting (HRM) for the authentication of gadoid species: Atlantic cod (Gadus morhua), Pacific cod (Gadus macrocephalus), Alaska pollock (Theragra chalcogramma) and saithe (Pollachius virens). Two DNA barcode regions, namely cytochrome c oxidase subunit I (COI) and cytochrome b (cytb), were analysed in silico to identify genetic variability among the four species and used, subsequently, to develop a real-time PCR method coupled with HRM analysis. The cytb mini-barcode enabled best discrimination of the target species with a high level of confidence (99.3%). The approach was applied successfully to identify gadoid species in 30 fish-containing foods, 30% of which were not as declared on the label. Herein, a novel approach for rapid, simple and cost-effective discrimination/clustering, as a tool to authenticate Gadidae fish species, according to their genetic relationship, is proposed.


Assuntos
Citocromos b/genética , Código de Barras de DNA Taxonômico , Complexo IV da Cadeia de Transporte de Elétrons/genética , Gadiformes/genética , Animais , Sequência de Bases , Gadiformes/classificação , Gadiformes/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Alinhamento de Sequência
8.
Crit Rev Food Sci Nutr ; 57(15): 3281-3296, 2017 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26714098

RESUMO

Gadiform order includes several fish families, from which Gadidae and Merlucciidae are part of, comprising the most commercially important and highly appreciated fish species, such as cod, pollock, haddock, and hake. Parvalbumins, classified as calcium-binding proteins, are considered the main components involved in the majority of fish allergies. Nine and thirteen parvalbumins were identified in different fish species from Gadidae and Merlucciidae families, respectively. This review intends to describe their molecular characterization and the clinical relevance, as well as the prevalence of fish allergy. In addition, the main protein- and DNA-based methods to detect fish allergens are fully reviewed owing to their importance in the safeguard of sensitized/allergic individuals.


Assuntos
Alérgenos/imunologia , Peixes/imunologia , Hipersensibilidade Alimentar/imunologia , Parvalbuminas/imunologia , Animais , Especificidade de Anticorpos , Humanos , Alimentos Marinhos
9.
Mol Cell Probes ; 29(6): 473-478, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26079045

RESUMO

The consumption of plant food supplements (PFS) has been growing globally, with an increase of misleading labeling and fraudulent practices also being reported. Recently, the use of molecular biology techniques has been proposed to detect botanical adulterations, one of the possible frauds in PFS. However, difficulties in recovering DNA from some PFS samples have been described. Aiming at using DNA-based methods for the unequivocal identification of plant species in PFS, adequate DNA isolation is required. However, PFS often contain pharmaceutical excipients known to have adsorbent properties that might interfere with DNA extraction. Thus, the aim of this work was to assess the effect of different excipients (talc, silica, iron oxide and titanium dioxide) on the recovery/amplification of DNA. For that purpose, known amounts of template maize DNA were spiked either to PFS or to model mixtures of excipients and quantified by real-time PCR. The tested excipients evidenced clear adsorption phenomena that justify the hampering effect on DNA extraction from PFS. The use of either 10% talc or 0.5% dyes completely adsorbed DNA, resulting in negative PCR amplifications. For the first time, pharmaceutical excipients were shown to affect DNA extraction explaining the inability of recovering DNA from some PFS samples in previous studies.


Assuntos
DNA de Plantas/análise , DNA de Plantas/isolamento & purificação , Suplementos Nutricionais/análise , Excipientes/química , Adsorção , Compostos Férricos/química , Contaminação de Alimentos/análise , Técnicas de Amplificação de Ácido Nucleico/métodos , Dióxido de Silício/química , Talco/química , Titânio/química , Zea mays/genética
10.
Food Funct ; 5(12): 3151-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25277724

RESUMO

Among aminoacidopathies, phenylketonuria (PKU) is the most prevalent one. Early diagnosis in the neonatal period with a prompt nutritional therapy (low natural-protein and phenylalanine diet, supplemented with phenylalanine-free amino acid mixtures and special low-protein foods) remains the mainstay of the treatment. Data considering nutrient contents of cooked dishes is lacking. In this study, fourteen dishes specifically prepared for PKU individuals were analysed, regarding the lipid profile and iron and zinc contents. These dishes are poor sources of essential nutrients like Fe, Zn or n-3 fatty acids, reinforcing the need for adequate supplementation to cover individual patients' needs. This study can contribute to a more accurate adjustment of PKU diets and supplementation in order to prevent eventual nutritional deficiencies. This study contributes to a better understanding of nutrient intake from PKU patients' meals, showing the need for dietary supplementation.


Assuntos
Dieta com Restrição de Proteínas/normas , Proteínas Alimentares/análise , Suplementos Nutricionais/análise , Fenilcetonúrias/dietoterapia , Culinária , Proteínas Alimentares/metabolismo , Proteínas Alimentares/uso terapêutico , Humanos , Avaliação Nutricional , Fenilalanina/análise , Fenilcetonúrias/metabolismo
11.
Food Chem ; 138(1): 687-92, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23265541

RESUMO

Broa is a maize bread highly consumed and appreciated, especially in the north and central zones of Portugal. In the manufacturing of broa, maize flour and maize semolina might be used, besides other cereals such as wheat and rye. Considering the needs for genetically modified organism (GMO) traceability in highly processed foods, the aim of this work was to assess DNA degradation, DNA amplification and GMO quantification along breadmaking process of broa. DNA degradation was noticed by its decrease of integrity after dough baking and in all parts of bread sampling. The PCR amplification results of extracted DNA from the three distinct maize breads (broa 1, 2 and 3) showed that sequences for maize invertase gene and for events MON810 and TC1507 were easily detected with strong products. Real-time PCR revealed that quantification of GMO was feasible in the three different breads and that sampling location of baked bread might have a limited influence since the average quantitative results of both events after baking were very close to the actual values in the case of broa 1 (prepared with maize semolina). In the other two maize breads subjected to the same baking treatment, the contents of MON810 maize were considerably underestimated, leading to the conclusion that heat-processing was not the responsible parameter for that distortion, but the size of particle and mechanical processing of raw maize play also a major role in GMO quantification.


Assuntos
Pão/análise , Farinha/análise , Alimentos Geneticamente Modificados , Plantas Geneticamente Modificadas/química , Zea mays/química , Zea mays/genética , Culinária , Plantas Geneticamente Modificadas/genética , Reação em Cadeia da Polimerase , Portugal
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