Desarrollo de una unidad didáctica centrada en la alimentación humana, social y culturalmente contextualizada

A study of the alternative conceptions of students of several educational levels about basic feeding is carried out. These alternative conceptions show many of the characteristics which have already been mentioned and seem to evolve towards a greater degree of differentiation, although in each educational level diverse alternative conceptions coexist. The contributions of this and other research have been utilized in the design of a teaching unit about this subject, which has been implemented and evaluated for a posterior revision of changes produced in the students alternative conceptions about feeding

Optical interferometry- from astronomy to art

After more than a century, Michelson’s interferometer is still at the forefront of scientific investigation. While the first application was in astronomy, it is now used as a novel technique in a wide range of subjects, notably in the form of Optical Coherence Tomography used primarily for biomedical applications. This paper will introduce a new application of the interferometer for the examination of art for conservation purposes

Numerical simulation of a supersonic ejector for vacuum generation with explicit and implicit solver in openfoam

Supersonic ejectors are used extensively in all kind of applications: compression of refrigerants in cooling systems, pumping of volatile fluids or in vacuum generation. In vacuum generation, also known as zero-secondary flow, the ejector has a transient behaviour. In this paper, a numerical and experimental research of a supersonic compressible air nozzle is performed in order to investigate and to simulate its behaviour. The CFD toolbox OpenFOAM 6 was used, with two density-based solvers: explicit solver rhoCentralFoam, which implements Kurganov Central-upwind schemes, and implicit solver HiSA, which implements the AUSM+up upwind scheme. The behaviour of the transient evacuation ranges between adiabatic polytropic exponent at the beginning of the process and isothermal at the end. A model for the computation of the transient polytropic exponent is proposed. During the evacuation, two regimes are encountered in the second nozzle. In the supercritic regime, the secondary is choked and sonic flow is reached. In the subcritic regime, the secondary flow is subsonic. The final agreement is good with the two different solvers, although simulation tends to slightly overestimate flow rate for large values region.Peer ReviewedPostprint (published version

The Behavioral Regulation in Exercise Questionnaire (BREQ-3) Portuguese-Version: Evidence of Reliability, Validity and Invariance Across Gender

This study has as prime objective to analyze the psychometric properties of the Behavioral Regulation Exercise Questionnaire (BREQ-3) in a sample of Portuguese exercisers and invariance across gender. Two independent samples (448 calibration; 374 validation), aged between 16 and 78 years (M = 40.29; SD = 16.24), of both gender, (495 female; 327 male) were enrolled in this study. The results show that the original model (six factors; 24 items) did not fit to the data in a satisfactory way (χ 2 = 977.49; df = 237; B-S p < 0.001; SRMR = 0.07; NNFI = 0.80; CFI = 0.83; RMSEA = 0.08; 90% CI = 0.08–0.09). After removing six items (one for each factor), the model (six factors; 18 items) adjustment improved in a satisfactory way in both samples: calibration (χ 2 = 331.86; df = 120; B-S p < 0.001; SRMR = 0.06; NNFI = 0.91; CFI = 0.93; RMSEA = 0.06; 90% CI 0.06–0.07) and validation (χ 2 = 254.08; df = 120; B-S p < 0.001; SRMR = 0.04; NNFI = 0.93; CFI = 0.95; RMSEA = 0.06; 90% CI = 0.05–0.06). Results also showed model invariance across gender (1CFI ≤ 0.01). The Portuguese version of BREQ-3 (six factors; 18 items) is a valid and reliable measurement instrument to measure behavior regulation underlying self-determination theory in the exercise domain. However, the evidence also indicated that additional studies are needed to address the fragilities of the original model (six factors; 24 items).info:eu-repo/semantics/publishedVersio

Variations in caffeine and chlorogenic acid contents of coffees: what are we drinking?

The effect of roasting of coffee beans and the extraction of ground coffee with different volumes of hot pressurised water on the caffeine and the total caffeoylquinic acids (CQAs) content of the resultant beverages was investigated. While caffeine was stable higher roasting temperatures resulted in a loss of CQAs so that the caffeine/CQA ratio was a good marker of the degree of roasting. The caffeine and CQA content and volume was determined for 104 espresso coffees obtained from coffee shops in Scotland, Italy and Spain, limited numbers of cappuccino coffees from commercial outlets and several instant coffees. The caffeine content ranged from 48–317 mg per serving and CQAs from 6–188 mg. It is evident that the ingestion of 200 mg of caffeine per day can be readily and unwittingly exceeded by regular coffee drinkers. This is the upper limit of caffeine intake from all sources recommended by US and UK health agencies for pregnant women. In view of the variable volume of serving sizes, it is also clear that the term “one cup of coffee” is not a reproducible measurement for consumption, yet it is the prevailing unit used in epidemiology to assess coffee consumption and to link the potential effects of the beverage and its components on the outcome of diseases. More accurate measurement of the intake of coffee and its potentially bioactive components are required if epidemiological studies are to produce more reliable information

Motivational determinants of physical education grades and the intention to practice sport in the future

Self-Determination Theory (SDT) is amongst motivational frameworks the most popular and contemporary approach to human motivation, being applied in the last decades in several domains, including sport, exercise and physical education (PE). Additionally, Achievement Goal Theory (AGT) has presented evidence of how contextual factors may influence student's behavior in this particular context. The main purpose of this study was to analyze the motivational climate created by the teacher in the classroom, students' satisfaction of Basic Psychological Needs (BPN), and how their behavioral regulation could explain PE grades and intention to practice sports in the future.Funding: This project was supported by the National Funds through FCT – Portuguese Foundation for Science and Technology (UID/ DTP/04045/2013) – and the European Fund for Regional Development (FEDER) allocated by European Union through the COMPETE 2020 Programme (POCI-01-0145FEDER-006969) – Competitiveness and Internationalization (POCI).info:eu-repo/semantics/publishedVersio

Teams as Complex Adaptive Systems: Reviewing 17 Years of Research

At the turn of the century Arrow, McGrath, and Berdahl (2000) portrayed teams as complex adaptive systems (CAS). And yet, despite broad agreement that this approach facilitates a better understanding of teams, it has only now been timidly incorporated into team research. To help fully incorporate the logic of teams as CAS in the science of teams, we review extant research on teams' approached from a nonlinear dynamical system theory. Using a systematic review approach, we selected 92 articles published over the last 17 years, in order to integrate what we know about teams as CAS. Our review reveals the evidence supporting teams as CAS, and the set of analytical techniques to analyze team data from this perspective. Our work contributes to teams' theory and practice by offering ways to identify both research methods and managing techniques that scholars and practitioners may apply to study and manage teams as CAS

Regeneração de plantas do Elaeis oleifera e de seu híbrido com Elaeis guineensis via embriogênese somática

Aiming to obtain plantlets regeneration of "caiaué" (Elaeis oleifera) plants and of their hybrid with African oil palm plants (Elaeis guineensis) via somatic embryogenesis, zygotic embyos were inoculated into modified Murashige & Skoog 1962 (MS) medium, plus 2,4 dichlorophenoxyacetic acid and N6 - (∆2 - isopentenyl) adenine (2iP). The embryos formation and subsequent shoots growth were obtained after the developed calli were subcultured in a sequence of modified MS media without auxin. Histological differences were found between primary and secondary calli. The rooting of shoots was induced by naphthaleneacetic acid (NAA). The plantlets were put In a prenursery after a short period under high humidity conditions. Visando a alcançar a regeneração de palmeiras caiaué (Elaeis oleifera) e de seu híbrido com dendezeiro (Elaeis guineensis) via embriogênese somática, foram inoculados embriões zigóticos em meio modificado Murashige & Skoog 1962 (MS), mais ácido 2,4 – diclorofenoxiacético (2,4-D) e N6 - (∆2 - isopentenil) adenina (2iP). A formação de embriões e o seu subsequente crescimento foram obtidos depois de os calos terem sido transferidos para uma sequência de meios MS sem auxina. Diferenças histológicas foram encontradas entre calos primários e secundários. O enraizamento das plântulas foi induzido com ácido naftaleneacético (ANA). As mudas foram colocadas em pré-viveiros, após um curto período sob condições de alta umidade

Fluctuations of rest and activity periods in the intermittent growth of rubber tree nursery seedlings

Em plantas de seringueira, na fase de viveiro, foram constatados períodos de atividade e de repouso dos entrenós, por medições dos comprimentos dos fluxos. Verificou-se uma desuniformidade na entrada em atividade da gema apical e, consequentemente, um descompasso na emissão e duração dos folíolos arroxeados (estádio fenológico B). Estes fatos dificultariam um controle mais flexível em relação ao Microcyclus ulei e à Erinnyis ello.In nursery rubber tree seedlings the periods of rest and growth activity of new flushes were determined by measuring the flush length. There was no synchronization in the outcome of apical meristem activity, so that plants in the leaflet stage B (anthocyanin rich red leaflets) were found individually at different time. This fact renders difficult the chemical control of leaf diseases and pests in nurseries such as South American Leaf Blight caused by Microcyclus ulei and the leaf-eater caterpillar (Erinnyis ello)