Browsing by Issue Date, starting with "2024-05-14"
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- Aplicação de dietas piloto de microalgas em nutrição de reprodutores de amêijoa (Ruditapes philippinarum)Publication . Pinto, João Ribeiro; Baptista, Teresa Maria CoelhoA amêijoa japonesa (Ruditapes philippinarum) tem sido uma das espécies mais amplamente introduzidas para fins de aquacultura na Europa devido ao seu elevado crescimento, resistência e facilidade de captura e forte procura no mercado. A obtenção de sementes de amêijoa para aquacultura dependia, até recentemente, da recolha em meio selvagem, no entanto, durante as últimas duas décadas, foi observado um grave declínio nas populações de bivalves refletindo-se diretamente na disponibilidade de sementes. Estas limitações levaram a um aumento da necessidade de reprodução controlada em maternidades e por consequente da necessidade de uma dieta equilibrada e formulada para a nutrição de bivalves que esteja disponível comercialmente e que permita o fornecimento contínuo de alimento. O objetivo do presente estudo foi avaliar o efeito de cinco dietas no acondicionamento de reprodutores de R. philippinarum das quais três foram selecionadas para avaliar o seu impacto a nível do desenvolvimento gonadal, sendo utilizada uma dieta controlo a base de microalgas vivas (dieta A), um concentrado líquido à base de microalgas inertes (dieta B) e um pó piloto à base de microalgas inertes combinadas com probióticos (dieta E). No final do acondicionamento a dieta E revelou ter efeitos positivos no desenvolvimento gonadal dos reprodutores apresentando a maior proporção de animais maduros (IG=4,07)em comparação com a dieta A (IG=3,20). Em termos nutricionais a dieta A apresentou um teor lípido significativamente mais elevado (73,92±41,79 μg mg-1 PSLC) enquanto a dieta E se destacou pelo teor proteico (846,65±289,99 μg mg-1 PSLC). Adicionalmente os dados sugerem que o decréscimo no índice de condição dos reprodutores esteja associado à ocorrência de uma desova no início do acondicionamento uma vez que quando estes foram adquiridos já se encontravam maduros.
- Physical Activity, Anxiety, Depression, and Body Image in Trans Individuals: An Exploratory StudyPublication . Oliveira, Joana; Monteiro, Diogo; Jacinto, Miguel; Matos, Rui; Amaro, Nuno; Rodrigues, Filipe; Antunes, RaulPhysical activity (PA), mental health, and body image are some important health topics in the transgender population that have been recently discussed and appear to play a crucial role in the quality of life of the trans population. This study aims to elucidate the complex interplay of these variables and their implications for the well-being of trans individuals. Methods: In a cross-sectional study, 75 Portuguese transgender individuals (M = 23.68; SD ± 6.59) were recruited to participate in this study. The participants completed three questionnaires related to the assessment of physical activity (IPAQ), depressive and anxious symptomatology (HADS), and satisfaction with body image (BISQp). Results: Trans individuals showed a total energy expenditure of 3316.40 metabolic equivalent tasks (METS), had a moderate level of anxiety symptomatology, and low levels of satisfaction with body image. Satisfaction with body image was negatively associated with anxiety (r = −0.441, p < 0.01) and depression symptomatology (r = −0.600, p < 0.01). Conclusions: The implementation of inclusive programs that promote body acceptance and coping strategies, particularly within the context of physical exercise, may help alleviate distress related to body image dissatisfaction while also addressing underlying anxiety and depression symptoms.
- Characterization of the lifestyle and well-being of students from the Polytechnic of LeiriaPublication . Santos, Daniel Augusto Bertoldo; Santos, Rui Filipe Vargas de Sousa; Ferreira, Susana Raquel CarvalhoEntering higher education marks a significant juncture in a student’s life. It often involves a shift towards independence, characterized by a distancing from family and friends, increased responsibilities, and greater autonomy in decision-making. These changes can influence well-being and various aspects of lifestyle, such as dietary habits, exercise routines, alcohol and drug use, and sexual behavior. Despite the initial excitement, this transition may also induce stress and anxiety. Academic demands, including grades, exams, and deadlines, as well as the newfound responsibilities of managing one’s schedule, finances, and social relationships, all affect the well-being. Hence, several studies recently conducted on college students have highlighted the importance of monitoring their well-being, especially since several reports have indicated a significant increase in mental health issues among college students, such as depression and anxiety. In particular, the Short Multidimensional Inventory Lifestyle Evaluation (SMILE), developed in 2020, is a 43-item self-rated questionnaire consisting of 7 domains, allowing a multidimensional evaluation of a (healthy) lifestyle. Within this context, a web survey was conducted among students at the Polytechnic of Leiria. This survey collected socio-demographic data, SMILE scores and clinical variables data, including screening for depression and anxiety. The key insights gleaned from the statistical analysis of the obtained data are summarized, particularly focusing on describing lifestyle and well-being, discerning differences between categories, and validating the survey instrument. Two supervised learning classification methodologies (logistic regression and decision trees) were applied to identify depression and anxiety issues based on responses to the survey. The reliability of these classifications were carry out using confusion matrix, accuracy, sensitivity, specificity, predictive values, and the area under the ROC curve in a test sample. The results reveal that lower SMILE scores are associated with positive screening of depression/anxiety in higher education students, despite the reliability appears insufficient to confidently recommend its use for screening depression and/or anxiety disorders. However, it enables the characterization of students’ lifestyles, the assessment of their well-being levels, and, consequently, the identification of potential mental health issues.
- Improvement of European native clams’ cultivationPublication . Nunes, Telma Vieira; Baptista, Teresa Maria CoelhoIn recent years, clam production in Europe has declined due to various factors, including overfishing, abiotic stress, diseases, and recruitment failure. Seed production in hatcheries has become essential to ensure the sustainability of clam production. Artificial breeding conditioning enables hatcheries to extend their production season, reducing dependency on the specific period when wild bank clams naturally mature. In many bivalve molluscs determining sex and reproductive stage non-lethally is challenging. In bivalve aquaculture, monitoring sexual maturation is crucial for determining the optimal time to induce spawning events for seed production. Anaesthesia is commonly used in aquaculture to facilitate tissue biopsies and for gametogenesis studies. The primary goal of this study was to enhance cultivation methods in commercial farming of native European species like Ruditapes decussatus, particularly during critical phases such as conditioning. Initially, the study evaluated the effect of a sandy substrate on R. decussatus broodstock conditioning. Subsequently, an assay was conducted to develop a non-lethal method for assessing gonad development stage and sex during conditioning, as well as for collecting tissue samples for later laboratory analysis. This methodology was also tested on clams of the species Venerupis corrugata. Adult specimens of R. decussatus were kept in an open system with and without sand during conditioning. Regular samplings were conducted to assess gonadal development, evaluating parameters such as condition index, histological analysis, and biochemical composition (glycogen, protein, and lipids). The results indicated that using sand as substrate did not impact gonadal maturity progression. In terms of biochemical composition, there was an observed increase in protein content during the conditioning period. Significant differences in biochemical composition were noted between the two conditions (with sand/without sand) at the end of the conditioning period. For the method of collecting biological samples, individuals of each species, R. decussatus, and V. corrugata, were anesthetized with c magnesium chloride (MgCl2.6H2O) at a concentration of (50g/L). The percentage of anesthetized clams was assessed every hour to determine the effectiveness of the anesthetic. In a subsequent trial, the optimal dosage of the anesthetic for each clam species was determined based on the initial test. Anesthetized clams were also subjected to gonad biopsies for sex determination. The results showed that at a concentration of 50g/L, it took 5 hours for 80% of V. corrugata individuals to become anesthetized. However, in R. decussatus, a mortality rate of 23.33% was observed among individuals undergoing biopsy procedures. Despite this, gonadal tissue collected via biopsy enabled the determination of an individual´s sex through microscopic examination. The results of this study represent a significant advancement in the conditioning of breeding stock in hatchery units. This study provides valuable insights into how the overall condition of individuals before exposure to experimental conditions influences conditioning success. Additionally, it facilitated the development of a non-lethal method for evaluating sex and collecting biological samples in R. decussatus and V. corrugata. These findings lay a solid foundation for future research and practical applications in bivalve aquaculture management and reproductive studies.