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Emotions and motivation are central to learning. Control–value theory (CVT) and expectancy–value theory (EVT) explain how emotions and expectations of success affect students’ task engagement. Supported by these two frameworks, this study investigates the emotion profiles for maths among fourth- and fifth-grade students (N = 6778) from three European countries and their links to motivation and achievement. Methods: Using latent profile analysis (LPA), we analysed the emotional profiles in students, as well as their associations with gender, country, grade, motivation and maths achievement. Results: Five profiles emerged in the grade 4 data (Bored, Bored and Anxious, Moderate, Happy and Anxious). All five profiles were visible in the grade 5 data, coupled with an additional sixth profile, which appeared only in grade 5 (i.e., Apprehensive–Happy). Girls were found more commonly in the Anxious profile and were less likely to appear in the Happy profile. Norwegian students were more prominent in the Bored and Moderate profiles. Conversely, Portuguese students stood out more in the Anxious profile and were less present in the Bored and Moderate profiles. The Serbian dataset did not stand out, with a particular pattern observed in grade 4. Nevertheless, Serbian fifth graders were overly visible in the Bored and Anxious profile and less present in the Happy and Apprehensive–Happy groups. The Happy profile had higher scores for all task values except for cost and was, along with the Moderate profile, associated with higher achievement; the Bored and Anxious profile was associated with higher scores of cost value and lower achievement. Conclusions: A person-centred approach allowed for a more diverse view of how students experience emotions. These findings highlight the complex interplay between emotions, motivation and achievement, which is affected by cultural and educational contexts.

Elderberry (Sambucus nigra L.) hydrolate, derived from domestic steam distillation, holds promise as a multifunctional ingredient for skincare and cosmetic applications. This study investigates the chemical composition and biological activities of elderberry hydrolate obtained through steam distillation. Despite the growing interest in elderberry hydrolate, there has been a lack of comprehensive studies elucidating its chemical composition and potential bioactive constituents. To address this gap, we conducted a detailed analysis of elderberry hydrolate’s composition, antioxidant activity, and antigenotoxicity. Genotoxic evaluation and antioxidant assays (ABTS, DPPH) were conducted to assess its biological properties. We obtained elderberry hydrolate with a notable transfer of aromatic compounds through the steam distillation process, highlighting its efficacy and sustainability. The chemical characterization identified vital compounds, including phenylacetaldehyde, 2-acetyl-pyrrole, and an unidentified major component, collectively contributing to the hydrolate’s aromatic and biological properties. The genotoxic evaluation using the Comet assay demonstrated the hydrolate’s protective effects against DNA damage induced by hydrogen peroxide and streptonigrin. The optimal DNA protection was observed at 10% (w/v), attributed to the antioxidant activity of the identified compounds. The hydrolate exhibited significant antioxidant potential, demonstrating concentration-dependent responses and correlating higher concentrations with increased antioxidant activity. These findings underscore the multifaceted attributes of elderberry hydrolate, positioning it as a promising natural ingredient for skincare. This study supports elderberry hydrolate as a valuable natural and sustainable product development resource.

Family involvement and participation in education (FIPE) profoundly impacts the quality of students’ academic and social development. Initial teacher education contribution in fostering attitudes, skills, and strategies for effective FIPE is therefore unquestionable. We aimed to find out to what extent Portuguese pre-service teachers are prepared to engage families. A document analysis was conducted to establish explicit information regarding FIPE within initial teacher education syllabi. Out of 621 syllabi across 36 master’s courses from 25 institutions, only 98 included some information on FIPE. A mere 12 syllabi, from seven institutions, exclusively addressed family–school relationships. Our study covered over 87% of the master’s courses and syllabi, exposing inconsistencies in their educational aims, content, and recommended literature. These findings highlight discrepancies within the initial teacher education syllabi and underscore the need for the enhanced training of pre-service teachers in FIPE. It is crucial to promote more in-depth and explicit syllabi to promote effective family engagement and enrich initial teacher education programs.

Lemon is a fruit rich in antioxidant properties and has several health benefits, namely the reduction of skin edema and anticarcinogenic properties, which are due to its high content of bioactive compounds. Melatonin can improve and preserve the properties of lemon for longer and also has health benefits. The aim of this study was to evaluate the effects of oral administration of lemon juice after melatonin treatment on murinometric parameters of wild-type (WT) mice and transgenic mice carrying human papillomavirus (HPV). Two trials were performed for oral administration of the lemon extract compound: in drinking water and in diet. First of all, lemons were treated by immersion with melatonin at 10 mM. Then, lemons were squeezed, and the juice obtained was freeze-dried and stored to be subsequently added to drinking water or diet, according to the assay. Thus, mice were divided into eight groups in the drink assay (each with n = 5): group 1 (G1, WT, control), group 2 (G2, WT, 1 mL lemon), group 3 (G3, WT, 1.5 mL lemon), group 4 (G4, WT, 2 mL lemon), group 5 (G5, HPV16, control), group 6 (G6, HPV16, 1 mL lemon) group 7 (G6, HPV16, 1.5 mL lemon) and group 8 (G6, HPV16, 2 mL lemon). The diet assay was divided into four groups: group 1 (G1, WT, control), group 2 (G2, WT, 4 mL lemon), group 3 (G3, HPV16, control) and group 4 (G4, HPV16, 4 mL lemon). In the drink assay, the highest concentration of melatonin (308 ng/100 mL) was for groups 4 and 8, while in the food assay, there was only one concentration of melatonin (9.96 ng/g) for groups 2 and 4. Both trials lasted 30 days. During this time, body weight, food and water were recorded. Afterward, they were sacrificed, and samples were collected for different analyses. At the concentrations used, the lemon juice with melatonin had no adverse effects on the animals’ health and showed a positive outcome in modifying weight gain and enhancing antioxidant activity in mice. Moreover, a reduction in the incidence of histological lesions was observed in treated animals. Further research is needed to better understand the effects of lemon extract on health and treatment outcomes in this animal model.

The development of new therapeutic options for Parkinson’s disease (PD) requires formulations able to mitigate both brain degeneration and motor dysfunctions. SC-Nanophytosomes, an oral mitochondria-targeted formulation developed with Codium tomentosum membrane polar lipids and elderberry anthocyanin-enriched extract, promote significant brain benefits on a rotenone-induced rat model of PD. In the present work, the effects of SC-Nanophytosome treatment on the skeletal muscle tissues are disclosed. It is unveiled that the rotenone-induced PD rat model exhibits motor disabilities and skeletal muscle tissues with deficient activity of mitochondrial complexes I and II along with small changes in antioxidant enzyme activity and skeletal muscle lipidome. SC-Nanophytosome treatment mitigates the impairment of complexes I and II activity, improving the mitochondrial respiratory chain performance at levels that surpass the control. Therefore, SC-Nanophytosome competence to overcome the PD-related motor disabilities should be also associated with its positive outcomes on skeletal muscle mitochondria. Providing a cellular environment with more reduced redox potential, SC-Nanophytosome treatment improves the skeletal muscle tissue’s ability to deal with oxidative stress stimuli. The PD-related small changes on skeletal muscle lipidome were also counteracted by SC-Nanophytosome treatment. Thus, the present results reinforces the concept of SC-Nanophytosomes as a mitochondria-targeted therapy to address the neurodegeneration challenge.

Regular exercise has been shown to be one of the most important lifestyle influences on improving functional performance, and decreasing morbidity and all-cause mortality among older people. However, although there is some evidence on the effects of aerobic training on oxidative stress, there is little information regarding the effects of multicomponent exercise (dual-task training) and combination of exercise with cognitive stimulation on oxidative stress. In this context, the aim of this study was to verify the effects of a multicomponent exercise program on physical fitness and cognitive function in the elderly with mild cognitive impairment and determine the role of oxidative stress and brain-derived neurotrophic factor (BDNF). At baseline, 37 elderly nursing home residents with mild cognitive impairment were divided into two groups: the control group (CG, n = 12, 81.8 years) and the experimental group (EG, n = 25, 83.2 years). These elderlies followed multicomponent exercise training for 24 weeks, with two sessions per week and 45–50 min per session. The exercises included both aerobic and strength exercises, considering functional movements and light to moderate intensity. Cognitive stimulation comprehended exercises based on word games, puzzles, mathematical calculations, forward and backward counting, computer exercises, exergames, and games on a balanced platform. Physical assessments (weight, height, and body mass index), health and functional parameters (fitness tests: chair stand, arm curls, chair sit-and-reach, eight feet up-and-go, back scratch, 6-min walking, feet together, semi-tandem, and full tandem), lipid profile (total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglycerides), measures of lipid peroxidation damage, thiobarbituric acid reactive substances (TBARS), total antioxidant capacity (TAC), and BDNF were measured in plasma, based on which analyses were performed before and after the 24 weeks of the multicomponent exercise intervention. The results showed an overall improvement in physical and functional performance. Regarding biochemical measures, multicomponent exercises lead to a significant decrease in oxidative damage. The results indicate that multicomponent exercise training induces benefits in functional capacity and reduces damage due to oxidative stress.

Most studies on the effects of physical exercise have focused on its influence on muscle tissue, forgetting its interference in liver function. Ageing leads to the progressive impairment of hepatic functions. Several biochemical and bioenergetics parameters were determined to test the impact of a lifelong aerobic training program in the hepatic age-related and the development of an adaptative response. Liver samples were collected from 28 male Wistar rats (4-week-old, 159.4 ± 11.9 g at the beginning of the protocol), randomly distributed into two groups: non-exercised or exercised and submitted to a treadmill exercise program (60 min/day, 5 days/week, at 70% of maximal running speed), for 24 (n = 9) or 54 weeks (n = 10). A maximal running speed test was performed to determine the training speed. Antioxidant enzyme activity, cellular redox status, oxidative stress, mitochondrial respiratory chain enzymes and respiratory activity were performed in liver samples. Lifelong exercise decreased the age-associated decline in mitochondrial dysfunction, increasing the respiratory rate in state 2 (mitochondrial respiration stimulated by the substrate in the absence of added ADP) (p = 0.03) and citrate synthase enzymatic activity (p = 0.007). Complex II (p < 0.0001) and IV (p < 0.001) showed a decrease in enzymatic activity. Ageing-related oxidative stress was also attenuated by physical exercise, as showed by the increase in first-line defense antioxidant enzymes (superoxide dismutase (p = 0.07) and catalase (p = 0.03)), decreased lipid peroxidation levels (p = 0.864 for total fraction, p = 0,27 for mitochondrial fraction) and higher glutathione reduced/oxidized ratio (p = 0.02). According to our results, the regular practice of exercise can prevent the liver’s mitochondrial dysfunction and loss of antioxidant system efficacy that may arise from ageing, highlighting the benefit of lifelong aerobic exercise in preventing age-related hepatic impairment and associated diseases.

Essential oils are natural compounds used by humans for scientific purposes due to their wide range of properties. Eugenol is mostly present in clove oil, while pulegone is the main constituent of pennyroyal oil. To guarantee the safe use of eugenol and pulegone for both humans and animals, this study addressed, for the first time, the effects of these compounds, at low doses (chronic toxicity) and high doses (acute toxicity), in laboratory animals. Thirty-five FVB/n female mice were randomly assigned to seven groups (n = 5): group I (control, non-additive diet); group II (2.6 mg of eugenol + 2.6 mg of pulegone); group III (5.2 mg of eugenol + 5.2 mg of pulegone); group IV (7.8 mg of eugenol + 7.8 mg of pulegone); group V (7.8 mg of eugenol); group VI (7.8 mg of pulegone); and group VII (1000 mg of eugenol + 1000 mg of pulegone). The compounds were administered in the food. Groups I to VI were integrated into the chronic toxicity study, lasting 28 days, and group VII was used in the acute toxicity study, lasting 7 days. Animals were monitored to assess their general welfare. Water and food intake, as well as body weight, were recorded. On the 29th day, all animals were euthanized by an overdose of ketamine and xylazine, and a complete necropsy was performed. Blood samples were collected directly from the heart for microhematocrit and serum analysis, as well as for comet assay. Organs were collected, weighed, and fixed in formaldehyde for further histological analysis and enzymatic assay. Eugenol and pulegone induced behavioral changes in the animals, namely in the posture, hair appearance and grooming, and in mental status. These compounds also caused a decrease in the animals’ body weight, as well as in the food and water consumption. A mortality rate of 20% was registered in the acute toxicity group. Both compounds modulated the serum levels of triglycerides and alanine aminotransferase. Eugenol and pulegone induced genetic damage in all animals. Eugenol increased the activity of the CAT enzyme. Both compounds increased the GR enzyme at the highest dose. Moreover, pulegone administered as a single compound increased the activity of the GST enzyme. Histopathological analysis revealed inflammatory infiltrates in the lungs of groups II, III, and IV. The results suggest that eugenol and pulegone may exert beneficial or harmful effects, depending on the dose, and if applied alone or in combination.

Mitochondria are an attractive target to fight neurodegenerative diseases due to their important functions for cells and the particularly close relationship between the functional connectivity among brain regions and mitochondrial performance. This work presents a mitochondria-targeted therapy designed to modulate the functionality of the mitochondrial respiratory chain and lipidome, parameters that are affected in neurodegeneration, including in Parkinson’s disease (PD). This therapy is supported by SC-Nanophytosomes constructed with membrane polar lipids, from Codium tomentosum, and elderberry anthocyanin-enriched extract, from Sambucus nigra L. SC-Nanophytosomes are nanosized vesicles with a high negative surface charge that preserve their properties, including anthocyanins in the flavylium cation form, under conditions that mimic the gastrointestinal tract pH changes. SC-Nanophytosomes, 3 µM in phospholipid, and 2.5 mg/L of EAE-extract, delivered by drinking water to a rotenone-induced PD rat model, showed significant positive outcomes on disabling motor symptoms associated with the disease. Ex vivo assays were performed with two brain portions, one comprising the basal ganglia and cerebellum (BG-Cereb) and the other with the cerebral cortex (C-Cortex) regions. Results showed that rotenone-induced neurodegeneration increases the α-synuclein levels in the BG-Cereb portion and compromises mitochondrial respiratory chain functionality in both brain portions, well-evidenced by a 50% decrease in the respiratory control rate and up to 40% in complex I activity. Rotenone-induced PD phenotype is also associated with changes in superoxide dismutase and catalase activities that are dependent on the brain portion. Treatment with SC-Nanophytosomes reverted the α-synuclein levels and antioxidant enzymes activity to the values detected in control animals. Moreover, it mitigated mitochondrial dysfunction, with positive outcomes on the respiratory control rate, the activity of individual respiratory complexes, and the fatty acid profile of the membrane phospholipids. Therefore, SC-Nanophytosomes are a promising tool to support mitochondria-targeted therapy for neurodegenerative diseases.

Transition to higher education is increasingly becoming a common stage in young adulthood, which highlights the importance of studying what could contribute for a better adaptation to higher education. The aim of this study was to explore the relationship between academic expectations, self-efficacy, and adaptation to higher education during the first two years of college (i.e., the first two years of a higher education degree). Portuguese college students participated in a longitudinal data collection resorting to the Academic Expectations Questionnaire (T1 and T3), the Self-Efficacy in Higher Education Scale (T2 and T3), and the Questionnaire for Higher Education Adaptation (T2 and T3). Structural equation modeling analysis was conducted to test a model correlating academic expectations, self-efficacy, and adaptation, as well as a mediation model where a full mediation of self-efficacy was observed between the relationship between academic expectations and higher education expectations. This study delivers a unique longitudinal view on the experience of the first two years of college, showing a significant role of expectations and self-efficacy in order to achieve a better adaptation process. Results are useful for institutions to adapt the way they present themselves and manage students’ expectations.

Based on the expectancy-value perspective on identity and identity formation, this paper explores the relationship between math identity (MI) and the dimensions of motivation (i.e. intrinsic value, attainment value, utility value and perceived competence) and math achievement in primary school. An additional aim of our research was to explore these relationships in different cultural contexts and investigate potential gender and grade differences concerning MI. The participants were 11,782 primary school students from Norway, Sweden, Estonia, Finland, Portugal and Serbia. All predictors from the motivation spectrum were significant for students' MI across the examined countries and had a stronger association with MI than math achievement. Among the motivational dimensions, intrinsic value had the strongest association with students' MI. Boys had significantly more positive math identities than girls in Estonia, Finland, Norway and Portugal. The results showed that the grade 4 students perceived themselves less as "math persons" than their grade 3 peers in all countries.

Research has shown that some students who underperform in mathematics overestimate their performance, while others who excel in mathematics underestimate it. Looking at this mismatch of performance and confidence judgement--the Dunning-Kruger effect (DKE)--the current study investigates how well students' confidence judgement and item-specific mathematics competence relate with each other and whether such a relationship differs across six European countries (i.e., Norway, Sweden, Finland, Estonia, Serbia and Portugal). We also examine whether perceived competence, mathematics identity, gender, socioeconomic status and immigration background predict this mismatch and whether these demographic factors function differently between the examined countries. The results show that the DKE could be found across grades three and four in all six countries. However, there are country-specific patterns regarding the relationship between performance, mathematics identity and perceived competence; the DKE; and how different demographic variables predict its occurrences in particular subpopulations.

Research on parental involvement is broad and specifies diverse kinds of parental practices that have specific associations with children's learning outcomes. However, the involvement of parents in education, the dynamics of parent-child interactions and the actions and practices they employ and their impact on student's motivation and achievement are intricate processes characterised by numerous intervening variables that require further clarification. In this study, we aimed to examine the association between parental beliefs and involvement and their children's motivation and mathematics achievement. Data were collected from 8071 third- and fourth-graders from six European countries and their parents. Students fulfilled the Expectancy-Value Scale, self-reporting on motivational aspects towards mathematics and performed two math tests to assess their performance. Parents also reported on their math attitudes, mindsets and involvement practices with their children. Data analysis was performed using structural equation modelling. Several theoretically meaningful associations were found in the tested model, showing the detrimental impacts of a fixed mindset on parents' practices. Furthermore, we found significant relationships between parents' attitudes towards mathematics, their practices and students' perceptions of math-related values and cost. Finally, associations between parental practices, the child's outcomes and the association between children's mathematics motivation and achievement were also observed. Some implications are presented, particularly concerning interventions with parents.

Abstract Background Several studies have focused on the assessment of students’ motivation because this construct is very important to understand students’ learning and how to enhance it. The Academic Self-Regulation Questionnaire (SRQ-A), based on the self-determination theory is a self-report instrument developed to access the reasons why students do their school work. However, there is no Portuguese version of this questionnaire for late elementary students. The primary goal of this research was to analyze the psychometric properties of a Portuguese version of SRQ-A in the domain of Mathematics with elementary school children. Methods Participants were 341 elementary school children ranging from 8 to 11 years old from the third and fourth grades. The Portuguese version of the SRQ-A included 24 items assessing four regulatory styles (external, introjected, identified, and intrinsic) in three behavioral categories (homework, classwork, and answering questions in mathematics lessons). To examine the psychometric properties of the instrument, we conducted an exploratory structural equation modeling (ESEM), measured gender and grade invariance, and calculated internal consistency indexes and temporal stability. Results ESEM analyses supported the original multidimensional structure of the measure with four regulatory styles using a reduced version of the instrument with 16 items. Correlations between the four regulatory styles revealed a simplex pattern consistent with the continuum of self-determination theory. Results showed adequate internal consistency for all regulatory styles (α ≥ .73; CR ≥ .76) and temporal stability (4-month test-retest ≥ .43). The questionnaire showed measurement and structural invariance across gender and grade. Finally, some gender differences were observed; on average, boys scored higher than girls in external regulation. No differences were observed between grades. Conclusions Our findings suggest that the Portuguese version of the SRQ-A has good psychometric properties providing adequate support for its use in educational research on motivational styles, including studies concerning gender and grade differences in self-regulation.

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This study aimed to characterize an animal model of colorectal cancer (CRC) in the early stages of disease development. Twenty-nine male Wistar rats were divided into two control groups (CTRL1 and CTRL2), receiving EDTA–saline injections and two induced groups (CRC1 and CRC2), receiving 1,2-dimethylhydrazine (DMH) injections for seven consecutive weeks. CRC1 and CTRL1 were euthanized at the 11th week, while CRC2 and CTRL2 were euthanized at the 17th week. DMH treatment decreased microhematocrit values and IL-6, ghrelin, and myostatin serum levels. Histopathological analysis of intestinal sections showed that DMH-treated rats were characterized by moderate to severe epithelial dysplasia. An adenoma was observed in one animal (CRC2 group), and the presence of inflammatory infiltrate at the intestinal level was primarily observed in DMH-treated animals. DMH also induced Ki-67 immunoexpression. The gut microbiota analysis showed a higher abundance of Firmicutes, Clostridia, Clostridiales, Peptostreptococcaceae, Blautia, Romboutsia, and Clostridium sensu stricto in CRC than CTRL rats, whereas Prevotellaceae, Prevotella, Akkermansia, and Lactobacillus levels were more prevalent in CTRL animals. Our results suggest that this model could be helpful to investigate chemoprevention in the early stages of CRC.

Academic expectations play a significant role in the quality of student adaptation and academic success. Previous research suggests that expectations are a multidimensional construct, making it crucial to test the measures used for this important characteristic. Because assessment of student adaptation to higher education comprises a multitude of personal and contextual variables, including expectations, shortened versions of assessment instruments are critical. In this article, confirmatory factor analysis was used to obtain a short version of the Academic Perceptions Questionnaire–Expectations (APQ-E). Participants were 3,017 first-year Portuguese college students. The results support the use of a shorter version of 24 items, distributed over six dimensions, with good reliability and validity.

Since the mid-1920s, parabens have been widely used as antimicrobial preservatives in processed foods and beverages, pharmaceuticals, and cosmetic products. Paraben use continues to generate considerable controversy, both in the general population and in the scientific community itself. The primary purpose of our study was to determine whether parabens (methyl and butyl at concentrations of 100 and 200 mg/kg body weight by subcutaneous injection) during pregnancy of adult female Wistar rats can have an impact on the F1 generation. As far as we know, we are the first to demonstrate that using parabens during pregnancy has negative repercussions on the mitochondrial bioenergetics and antioxidant activity of testicular germ cells in the F1 generation. Our study showed that there was a 48.7 and 59.8% decrease in the respiratory control index with 100 and 200 mg/kg of butylparaben, respectively. Cytochrome c oxidase activity was significantly inhibited (45 and 51%) in both groups. In addition, 200 mg/kg butylparaben promoted a marked decrease in citrate synthase activity, indicating that mitochondrial content decreased in the germ cells, especially spermatocytes and spermatids. Mitochondrial ROS production increased in groups exposed to parabens in a concentration-dependent manner, especially the butyl one (102 and 130%). The groups exposed to butylparaben showed an increase in superoxide dismutase (SOD) and catalase (CAT) activities, while glutathione reductase (GR) and glutathione S-transferase (GST) decreased. With methylparaben, only differences in SOD and GR were observed; for the latter, this only occurred with the highest concentration. The glutathione (GSH)/glutathione disulfide (GSSG) ratio did not undergo any significant change. However, there was a considerable increase in hydroperoxide content in animals exposed to butylparaben, with 100 and 200 mg/kg resulting in 98.6 and 188% increase, respectively. Furthermore, several other organs also showed alterations in antioxidant capacity due to paraben use. In summary, our study demonstrates that paraben use during pregnancy will cause severe changes in the mitochondrial bioenergetics and antioxidant capacity of testicular germ cells and the antioxidant capacity of several other F1 generation organs.

Grade retention is one of the most discussed and controversial educational measures, and yet, it is still widely applied in many countries. Research investigating the effects of grade retention on students' psychosocial variables presents mixed findings, partly due to the variables assessed, methodological issues, and the length of the studies. This study aimed to analyse both the short to medium and longitudinal effects of grade retention in grades 7 or 8 on Portuguese students' academic self-concept, self-esteem, goal orientations, and school career. Data were collected continuously over a 3-year span (once a year) and, again, 3 years after the third wave. After matching 477 students on several pretreatment variables using inverse probability treatment weighting with time-varying treatments (i.e., retention), our analytical sample consisted of 85 promoted students, 33 students retained in grade 7, and 32 students retained in grade 8. Our results showed that retained students did not differ from their promoted peers in self-esteem and goal orientations in the short, medium, or long term. The exception was for an increase in the academic self-concept of retained students, but only in short term. Finally, considering students' school career, grade retention was not predictive of further retention.

O estudo teve como objetivo investigar o impacto da transição, do 1º para o 2º Ciclo do Ensino Básico, na motivação, no autoconceito e na autoestima. Participaram neste estudo 848 alunos, em transição do 4º para o 5º ano, de escolas públicas do concelho de Loures, os quais responderam à EAAPA e à GOS. Os resultados evidenciam um aumento na autoestima e no autoconceito não académico e uma diminuição no autoconceito académico. Relativamente às orientações motivacionais verifica-se uma diminuição nas orientações de autovalorização e de autodefesa e um aumento nas orientações para a tarefa e para o evitamento.

Pretendeu-se caraterizar a motivação e as emoções associadas à matemática, e analisar de que modo estas variam em função do desempenho nesta disciplina e do género dos alunos. Participaram no estudo 232 crianças portuguesas do terceiro ano do ensino básico, que responderam ao AEQ-ES e à MMS. Os resultados evidenciaram caraterísticas motivacionais positivas dos alunos face à matemática. Também a emoção positiva, prazer, surgiu mais associada à matemática do que as negativas. Constatou-se pouco efeito do género tanto na motivação como nas emoções. Relativamente ao desempenho, este surgiu significativamente associado às caraterísticas motivacionais e emoções vivenciadas pelos estudantes.

Intrinsic Motivation Inventory (IMI) is a multidimensional measurement grounded on the Self-Determination Theory (SDT) used in assessing the subjective experiences of participants when developing an activity. The aim of this study is to analyze the characteristics of IMI among Portuguese students, testing four organizational models (unidimensional, multidimensional, hierarchical and bi-factor). A total of 3685 students from the 5th to the 12th grades (50.4% boys) participated in the study (M = 13.67, SD = 2.26). Two versions of IMI were used (First Language and Mathematics) with twenty-one items distributed over five subscales: Enjoyment, Perceived Competence, Pressure/Tension, Perceived Choice and Value/Utility. The confirmatory factor analysis corroborated the multidimensionality of intrinsic motivation, and that the bi-factor model presented the best fit indexes. This model showed the existence of one general factor, resulting from the contribution of all individual dimensions and the particularities of most of them. Furthermore, results also highlighted satisfactory reliability scores both through Cronbach's alpha scores and Composite reliability scores. These results indicate that this scale is appropriate to evaluate the underlying constructs of the theoretical model of SDT and allows for the calculation of a global measure of intrinsic motivation, as well as specific measures for their predictors.

Carcinogenesis induced by high-risk human papillomavirus (HPV) involves inflammatory phenomena, partially mediated by cyclooxigenase-2. In pre-clinical models of HPV-induced cancer, cyclooxygenase-2 inhibitors have shown significant efficacy, but also considerable toxicity. This study addresses the chemopreventive effect and hepatic toxicity of a specific cyclooxigensase-2 inhibitor, parecoxib, in HPV16-transgenic mice. Forty-three 20 weeks-old female mice were divided into four groups: I (HPV16−/−, n = 10, parecoxib-treated); II (HPV16−/− n = 11, untreated); III (HPV16+/−, n = 11, parecoxib-treated) and IV (HPV16+/−, n = 11, untreated). Parecoxib (5.0 mg/kg once daily) or vehicle was administered intraperitoneally for 22 consecutive days. Skin lesions were classified histologically. Toxicological endpoints included genotoxic parameters, hepatic oxidative stress, transaminases and histology. Parecoxib completely prevented the onset of epidermal dysplasia in HPV16+/− treated animals (0% versus 64% in HPV16+/− untreated, p = 0.027). Parecoxib decreases lipid peroxidation (LPO) and superoxide dismutase (SOD) activity and increases the GSH:GSSG ratio in HPV16+/− treated animals meaning that oxidative stress is lower. Parecoxib increased genotoxic stress parameters in wild-type and HPV16-transgenic mice, but didn’t modify histological or biochemical hepatic parameters. These results indicate that parecoxib has chemopreventive effects against HPV16-induced lesions while maintaining an acceptable toxicological profile in this model.

Keeping students back in the same grade – retention – has always been a controversial issue in Education, with some defending it as a beneficial remedial practice and others arguing against its detrimental effects. This paper undertakes an analysis of this issue, focusing on the differences in student motivation and self-related variables according to their retention related status, and the interrelationship between retention and these variables. The participants were 695 students selected from two cohorts (5th and 7th graders) of a larger group of students followed over a three-year project. The students were assigned to four groups according to their retention-related status over time: 1) students with past and recent retention; 2) students with past but no recent retention; 3) students with no past but recent retention; 4) students with no past or recent retention. Measures of achievement goal orientations, self-concept, self-esteem, importance given to school subjects and Grade Point Average (GPA) were collected for all students.Repeated measures MANCOVA analyses were carried out showing group differences in self-esteem, academic self-concept, importance attributed to academic competencies, task and avoidance orientation and academic achievement. To attain a deeper understanding of these results and to identify profiles across variables, a cluster analysis based on achievement goals was conducted and four clusters were identified. Students who were retained at the end of the school year are mainly represented in clusters with less adaptive motivational profiles and almost absent from clusters exhibiting more adaptive ones.Findings highlight that retention leaves a significant mark that remains even when students recover academic achievement and retention is in the distant past. This is reflected in the low academic self-concept as well as in the devaluation of academic competencies and in the avoidance orientation which, taken together, can undermine students' academic adjustment and turn retention into a risk factor.

Este trabalho investiga as interações entre os agentes econômicos, a fim de verificar a premissa de que a inovação e a competitividade em uma indústria são sistêmicas e coevoluem. Nesse sentido, utilizou­se a abordagem de sistema setorial de inovação (SSI), definida por Malerba, tendo em vista a relação entre as dimensões de análise: organizações, tecnologias e instituições, na Indústria Sucroalcooleira de Alagoas, a maior produtora e exportadora de açúcar e etanol da região Nordeste. Após uma pesquisa exploratória e descritiva, os resultados apontaram para uma interação positiva entre essas três dimensões de análise e mostraram que há interação entre as universidades e os centros de pesquisa, além de grande parte do avanço tecnológico advir de parcerias públicas e privadas. Destaca­se que o esforço de pesquisa se concentra na área genética e em inovações de processos. O estudo, assim, indica que há um sistema de inovação localmente circunscrito.

The aim of this work was to perform the histological characterization of the C. sativa leaves of three Portuguese cultivars to establish comparison among the leaves of the different quadrants in accord and with the cardinal points of the tree top and among different cultivars of this species, using light microscopy (OM) and scanning electron microscopy (SEM). Measurements were also carried out for the leaf tissue thickness, stomatal density, leaf area in the four tree top quadrants. The leaves turned to the North had lesser thickness of mesophyll mainly due to lower amount of palisade parenchyma. The stomatal density was significantly lower in these leaves, unlike the leaf area that has the highest expression.

Este estudo tem como objectivo principal a análise da estrutura hierárquica do autoconceito em adolescentes e, adicionalmente, a comparação dessa estrutura em alunos com e sem repetência no seu passado escolar. Participaram no estudo 943 alunos portugueses do 7º, 9º e 11º ano de escolaridade, que responderam a uma escala de autoconceito e de auto-estima. Os resultados obtidos sustentam a ideia de uma organização hierárquica do autoconceito e um modelo que subdivide o autoconceito em quatro factores de ordem superior. Os resultados sugerem, ainda, uma associação entre a dimensão comportamento e diferentes dimensões de ordem superior, nomeadamente as duas dimensões do autoconceito académico e o autoconceito social. Os resultados divergem quando tomamos alunos com maior e menor sucesso escolar, justificando maior atenção na investigação e na intervenção a este aspecto.The main goal of this research is to analyze the hierarchical structure of self-concept in adolescents and, additionally, to compare this structure in students who have failed in their academic career and in those who have not. Nine hundred and forty-three Portuguese students from the 7th, 9th and 11th grades participated in the research. They completed self-concept and self-esteem scales. Results support the assertion that self-concept is hierarchically structured, and also support a model that subdivides self-concept into four higher order factors. Results also suggest an association between the behavioral dimension and various different higher order dimensions, namely, the two academic self-concept dimensions and the social self-concept one. However, they show divergences when the structure of self-concept between achievers and underachievers is compared. This aspect needs to be examined with greater attention on future researches and interventions.

O primeiro objectivo do presente estudo é o de analisar a organização estrutural das crenças e teorias implícitas sobre a inteligência em participantes de sexo feminino com diferentes inserções sociais e papéis educativos (Mães e Não Mães, Professoras e Não Professoras). Por outro lado, pretende-se também pesquisar de que modo as mesmas podem ser influenciadas por dinâmicas sociocognitivas, como possíveis conflitos identitários em participantes que desempenhem duplo papel educativo, bem como o grau de familiaridade percepcionado pelos participantes com o objecto de representação “inteligência”. Do ponto de vista teórico, adopta-se a perspectiva da Teoria das Representações Sociais, entendidas como Princípios Organizadores de Crenças e Teorias Implícitas. Quanto ao primeiro objectivo, análises factoriais confirmatórias (subsequentes a análises exploratórias) mostram um modelo de organização estrutural de três factores, com fracas ou moderadas correlações entre si. Quanto ao segundo objectivo, análises multivariadas mostram que as Mães valorizam mais teorias inatistas (confirmando estudos anteriores), como possível forma de defesa das suas identidades sociais. Alguns resultados novos face à literatura surgem nesta investigação: as Mães são também as participantes que mais valorizam a imagem de criança inteligente como criança simultaneamente bem socializada, mas também autónoma e dinâmica na prossecução de objectivos ambiciosos. Finalmente, também como resultado novo, consta-se que os participantes sem qualquer posição face à questão da familiaridade com o objecto de representação, valorizam significativamente mais esta última teoria implícita. São sugeridos estudos futuros para esclarecimento destes resultados.

Este estudo teve como principal objetivo realizar uma análise diferencial do autoconceito artístico entre adolescentes que frequentavam o ensino artístico e os que frenquentavam o ensino regular. Responderam à Escala de Autoconceito Artístico e à Escala de Autoconceito e Autoestima para Adolescentes 226 estudantes de escolas da zona metropolitana de Lisboa, dos quais 108 frequentavam o ensino regular e 118 eram alunos de escolas artísticas de música, artes visuais e dança. Os resultados demonstraram que os níveis de autoconceito artístico diferiram de acordo com o contexto educativo: foram favorecidos os alunos do ensino artístico na maioria das dimensões artísticas. Contemplando apenas os alunos do ensino artístico, foi verificado que eles apresentaram níveis superiores na dimensão artística correspondente a sua área de especialização, comparativamente aos seus pares das outras áreas artísticas.