Trends and challenges of mathematic education in Mozambique (1975-2016)

Mathematics has always been a difficult issue, especially in the African countries. Mozambique is not an exception. This country had been colonized by Portugal until 1975. When the independence was obtained, a socialist regime was adopted (1977). The learning of mathematics entered the struggle against colonial and imperialistic ideas. Its best ally was Paulus Gerdes, one of the most relevant ethnomatematicians of the world, who carried out an intense promotion of this approach to mathematics in Mozambican school system. Albeit the great international impact of Gerdes’ ideas, Mozambique never implemented his methodology. When, at the end of the 80s, the country changed from socialism to liberalism, voting a democratic Constitution in 1990, its school system was aligned to the measures of International Monetary Fund (IMF) and World Bank (WB). The most recent ones are represented by the Millennium Development Goals. Despite the various reforms of Mozambican school system, the results of Mozambican children in mathematics are among the worst in Africa. The reasons of such a failure are here explained, through a historical approach based on national documents. The most recent experiences of school reform carried out by international agencies together with national institutions are stressed. The negative results obtained by the Mozambican learners as to mathematics are due to several reasons: 1) a lack of consideration of the Mozambican cultural substrate; 2) an improper massification of the school system, where the quality of instruction has been neglected; 3) the specific choice to marginalize mathematics education.info:eu-repo/semantics/publishedVersio

The teaching of history of science at the university: Some brief considerations

I teach history of science at the University of Udine, Italy. My students – about 25 – frequently the second and the third year at the faculty of Letters and Philosophy (now called “Polo Umanistico”). They have to pass a sole proof in history of science. Therefore, in this editorial, I would like to face the problems connected with the teaching of history of science to students who have a scarce knowledge of mathematics and who in their future will have probably few contacts with science and its history. Thus, two problems are particularly difficult in this case: 1) to choose the subject properly; 2) to choose the appropriate educational approach. Obviously, the choice of the subject is always important, but if one teaches history of science in a scientific faculty, the situation is, in a sense, easier: for example, at the faculty of physics, one could select a specific course each year, i.e., history of mechanics in a certain period, history of electromagnetism in the 19th century, the theory of optics as it is developed by an author or a series of authors (Euclid, Witelo, Kepler, Snell, Descartes, and so on), etc. Each subject could be dealt with by facing the particular research of each scholar and entering the specific mathematical arguments. This is not possible in a humanities faculty. Thence, I would like to explain my choice and to trace some general considerations

Des problèmes dans la classification des chênes, taxonomie en Europe et région méditerranéenne

Le genre Quercus présente de grandes difficultés taxonomiques car son polymorphisme élevé, a suscité, pour de très nombreux taxons, des descriptions qui souvent résultent de méthodes incertaines. En comparant, dans les principaux traités existants, la distribution et la classification des taxons du genre Quercus en Europe et dans la région méditerranéenne, on met en évidence une notable incertitude taxonomique : ceux qui, pour certains auteurs, sont des espèces à propement parler, ne sont pour d'autres que des sous-espèces ou variétés. Dans le présent travail, nous avons réalisés une compilation bibliographique en cherchant à regrouper les taxons, tels qu'ils sont décrits par divers auteurs, en un nombre limité d'espèces principales

Lung function with carvedilol and bisoprolol in chronic heart failure: is beta selectivity relevant?

BACKGROUND: Carvedilol is a beta-blocker with similar affinity for beta1- and beta2 receptors, while bisoprolol has higher beta1 affinity. The respiratory system is characterized by beta2-receptor prevalence. Airway beta receptors regulate bronchial tone and alveolar beta receptors regulate alveolar fluid re-absorption which influences gas diffusion. AIMS: To compare the effects of carvedilol and bisoprolol on lung function in patients with chronic heart failure (CHF). METHODS AND RESULTS: We performed a double-blind, cross-over study in 53 CHF patients. After 2 months of full dose treatment with either carvedilol or bisoprolol, we assessed lung function by salbutamol challenge, carbon monoxide lung diffusion (DLCO), including membrane conductance (DM), and gas exchange during exercise. FEV1 and FVC were similar; after salbutamol FEV1 was higher with bisoprolol (p<0.04). DLco was 82+/-21% of predicted with carvedilol and 90+/-20% with bisoprolol (p<0.01) due to DM changes. Peak VO2 was 17.8+/-4.5 mL/min/kg on bisoprolol and 17.0+/-4.6 on carvedilol, (p<0.05) with no differences in bronchial tone (same expiratory time) throughout exercise. Differences were greater in the 22 subjects with DLCO<80%. CONCLUSION: Carvedilol and bisoprolol have different effects on DLCO and response to salbutamol. DLCO differences, being DM related, are due to changes in active membrane transport which is under alveolar beta2-receptor control. Peak VO2 was slightly higher with bisoprolol particularly in CHF patients with reduced DLCO

In and out and out again: The travails of Brazil as a security provider in Africa

The story of Brazil as a contemporary security actor in Africa can prove a peculiar one. Marked by quick gains and an equally quick recognition over a short period of time, it has also been followed by an equally quick turnaround which has led, as of 2020, to a visible disengagement on the ground. We explore the main travails in this domain, which have compromised much of the gains previously obtained throughout the continent. The chapter begins with a general balance of the progress achieved between 2003 and 2016, followed by the highlights of the recent downturn. We then analyze a specific sub-area, namely, the inroads carried out at the defence industry level, in order to showcase the promises and contradictions often associated to what the country has offered across the Atlantic. We conclude by presenting some opportunities for a new pickup of Brazilian interest in the middle and long run

Unravelling the ultrafast dynamics of a N-BODIPY compound

Although the photophysics of BODIPY compounds has been widely investigated in the last few years, their analogues N-BODIPY, with nitrogen substitution at the boron center, did not receive comparable attention. In this work we report the synthesis and photochemical characterization of a substituted N-BODIPY compound, by means of a combined theoretical and spectroscopic approach. Compared to a standard BODIPY, the compound under investigation presents a lower fluorescence quantum yield (QY) in the visible region. The excited state relaxation dynamics of the dye was studied in different solvents, showing further fluorescence quenching in polar solvents, and excited state decay rates strongly dependent on the environment polarity. The role of the pendant moieties and the involvement of charge transfer states in the excited state dynamics was experimentally addressed by transient absorption spectroscopy, and further analyzed with TD-DFT calculations, which allowed precise assignment of the transient signals to the correspondent electronic configuration. The complete picture of the N-BODIPY behavior shows the presence of both charge transfer and localized states, influencing the observed photophysics to different amounts, depending on the excitation conditions and the surrounding environment

Inconsistent relationships among protection, benthic assemblage, habitat complexity and fish biomass in Mediterranean temperate rocky reefs

Marine Protected Areas (MPAs) have been proved to effectively protect and restore fish assemblages. There is mixed evidence regarding the effects of MPAs on benthic assemblages, habitat complexity, and how protection might mediate the effects of habitat features (including biotic and abiotic components) on fish assemblages, with very little information concerning temperate areas. Here, our aim is to assess how protection 1) influences benthic assemblages and habitat complexity, and 2) mediates the effects of habitat complexity on fishes. Using non-destructive methods (photosampling for shallow rocky benthic assemblages, and underwater visual census using strip transects for fish assemblages) to characterize benthic and fish assemblages, we sampled 15 Mediterranean locations, each including protected and unprotected sites. In all, we sampled 90 sites, and analyzed 2,760 photos and 800 replicated transects, gathering information on 44 benthic and 72 fish taxa. Abiotic, biotic and synthetic (i.e. combining the previous two) complexity indices have been computed to synthesize habitat features. Overall, whole benthic assemblages did not significantly differ between protected and unprotected conditions, but higher cover of the ecologically important erect algae belonging to the genus Cystoseira sensu lato was recorded within MPAs. Abiotic, biotic and synthetic complexity did not show clear patterns related to protection levels, displaying inconsistent responses between different locations. Our findings highlight that protection has a generally positive effect on fish biomass, this latter variable responding independently of the habitat complexity. Our study, in conclusion, confirms that MPAs can be effective to protect and restore rocky-reef assemblages, highlighting the need for more in-depth exploration of the mechanisms determining the different responses of benthic taxa to protection and how this can influence the associated fish assemblages