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Precursor models in the thinking of 3-8 year olds: entities between empirical and scientific knowledge
No full textΤο ζήτημα της προσέγγισης του των Φυσικών Επιστημών στην προσχολική και πρώτη σχολική ηλικία, αποτελεί τις τελευταίες δεκαετίες ένα ζήτημα έρευνας και εφαρμογής διαφορετικών γνωστικών περιοχών όπως η Ψυχολογία της μάθησης, η Επιστημολογία της γνωστικής ανάπτυξης, η Προσχολική Παιδαγωγική, η Διδακτική των Φυσικών Επιστημών. Η πολυπλοκότητα που απορρέει αναγκαστικά από την πολύπλευρη ή μονόπλευρη προσέγγιση επιμέρους ερωτημάτων, μερικές φορές δημιουργεί επιστημολογικές συγχύσεις που οδηγούν στην απόσβεση κρίσιμων ερωτημάτων για μια ορθολογική προσπάθεια μετατόπισης από τη βιωματική και αυθόρμητη σχέση της σκέψης των μικρών παιδιών σε δομικά ή/και λειτουργικά στοιχεία των Φυσικών Επιστημών. Ταυτοχρόνως η ανάδυση εκπαιδευτικών προτάσεων με χαλαρή θεωρητική θεμελίωση οι οποίες, για διάφορους λόγους, αποκτούν ευρεία διάδοση, προσθέτουν νέες παραμέτρους ασάφειας, τουλάχιστον στο ζήτημα της διάστασης της γνωστικής ανάπτυξης των μικρών παιδιών. Στο άρθρο αυτό γίνεται προσπάθεια να αποτυπωθεί η έννοια του "πρόδρομου" μοντέλου ως νοητικής οντότητας που παρεμβάλλεται μεταξύ της επιστημονικής σχολικής γνώσης και των εμπειριών των παιδιών, οικοδομείται στη σκέψη τους διαμέσου κατάλληλων δραστηριοτήτων και αποτελεί ένα σταθερό εργαλείο που προετοιμάζει τη νόηση των παιδιών για τη συγκρότηση των σχολικών επιστημονικών μοντέλων. Παράλληλα, εάν η σχετική έρευνα δείχνει ότι κάποια παιδιά στην ηλικία των 3-8 ετών είναι σε θέση να συγκροτούν ένα πρόδρομο μοντέλο στη σκέψη τους για κάποιο συγκεκριμένο φαινόμενο, αυτό μπορεί να αποτελεί στόχο των δραστηριοτήτων σε κάθε τύπου παιδαγωγικό πλαίσιο που επιλέγεται.The issue of the approach to Physical Sciences in pre-school and early school age has been an issue of research and application of different fields of knowledge such as the Psychology of learning, the Epistemology of Cognitive Development, Early Childhood Education, the Science Education. The complexity that necessarily results from the multifaceted or one-sided approach to individual questions sometimes creates epistemological confusions that lead to the damping of critical questions for a rational attempt to shift from the experiential and spontaneous relationship of young children's thinking to structural and/or functional elements of Physical Sciences. At the same time, the emergence of educational proposals with a loose theoretical foundation which, for various reasons, are becoming widely disseminated, adding new parameters of ambiguity at least on the issue of the dimension of cognitive development of young children. In this article an attempt is made to capture the concept of the precursor model as a mental entity that interposes itself between scientific school knowledge and children's experiences, is built in children's minds through appropriate activities and constitutes a stable tool that prepares children's minds for the formation of school scientific models. At the same time, if the relevant research shows that some children at the age of 3-8 years can form a precursor model in their thinking about a particular phenomenon, this can be the aim of activities in any type of pedagogical context chosen.
 
Οι ιδέες υποψήφιων νηπιαγωγών και δασκάλων για το ηλεκτρικό κύκλωμα
No full textΣτη διεθνή βιβλιογραφία καταγράφεται η κυρίαρχη αντίληψη πως μια ηλεκτρική πηγή μεταφέρει ρεύμα στο ηλεκτρικό κύκλωμα. Στον Ελλαδικό χώρο το ηλεκτρικό κύκλωμα διδάσκεται στην Πρωτοβάθμια και Δευτεροβάθμια Εκπαίδευση χωρίς να δίδεται έμφαση στην αποσταθεροποίηση της προαναφερθείσας αντίληψης. Στο πλαίσιο αυτό διερευνήθηκαν οι σχετικές αντιλήψεις 400 φοιτητριών/των του Τ.Ε.Α.Π.Η Αθήνας και του Π.Τ.Δ.Ε Ιωαννίνων, μέσω ερωτηματολογίου. Οι συμμετέχοντες δεν είχαν διδαχθεί το εν λόγω θέμα πέρα του πλαισίου της τυπικής τους εκπαίδευσης,. Η ανάλυση των αποτελεσμάτων έδειξε ότι ελάχιστοι εκπαιδευόμενοι προσεγγίζουν τον ρόλο της ηλεκτρικής πηγής μέσω του επιστημονικού προτύπου ενώ η συντριπτική πλειοψηφία διατυπώνει την άποψη ότι μια πηγή μεταφέρει κάτι (ρεύμα, φορτίο, τάση κτλ). Αναφορικά με τα κριτήρια βάσει των οποίων θεωρούν ότι μια διάταξη, με πηγές, καλώδια και λαμπτήρα, θα λειτουργήσει, φαίνεται ότι οι απαντήσεις τους είναι κυρίως προϊόντα «αφομοίωσης» της σχολικής γνώσης στο πλαίσιο της εναλλακτικής αντίληψης ότι μια πηγή μεταφέρει ρεύμα.As noted in the relevant literature, the dominant student conception is that an electric source transfers current into an electric circuit. In the Greek educational context, electric circuits are taught in both primary and secondary education without emphasis on destabilizing this prevailing conception. Within this framework, the views of 400 pre-service teachers from the Department of Early Childhood Education at the University of Athens and the Department of Primary Education at the University of Ioannina were investigated through a questionnaire. The participants had not received any instruction on the topic beyond their formal school education. Analysis of the results showed that only a small number of students approached the role of the electric source through the scientific model, while the vast majority expressed the idea that a source transfers “something” (current, charge, voltage, etc.). Regarding the criteria on which they based their decisions about whether a circuit—composed of sources, wires, and a bulb—would operate, their answers appear to be mainly the result of assimilation of school knowledge within the framework of the alternative conception that a source transfers current
Ἀνάλεκτα Σταγῶν καὶ Μετεώρων. Τεῦχος 2ο, Μετέωρα 2024
No full textΒιβλιογραφικὸ σημείωμα: Ἀνα΄λεκτα Σταγῶν καὶ Μετεώρων , τεῦχος 2ο. ISSN 2944-902
Le marxisme grec de la première moitié du XXe siècle entre théorie, politique et histoire: quelques réflexions préliminaires
No full textCet article se donne pour tâche d’examiner le marxisme grec de la première moitié du XXe siècle par référence au triptyque théorie, politique et histoire, tout en mettant en relief la manière dont ce courant intellectuel a traité la question de la “transition historique” au sein de la société grecque moderne. L’article fait valoir que, les textes marxistes grecs de l’époque ayant été, en règle générale, examinés sous un point de vue exclusivement historiographique, on a eu tendance à négliger leur aspect théorique, de même que les querelles entre leurs auteurs à propos de l’interprétation du matérialisme historique. Il n’en reste pas moins que, nonobstant l’économisme évident qui sous-tend ces textes ‒ un économisme reflété dans des ajustements naïfs de la célèbre “loi des cinq étapes de l’évolution sociale” aux impératifs de telle ou telle conjoncture politique ‒ les auteurs en question ont développé une réflexion historique qui a souvent mis à l’épreuve le déterminisme fondamental de leur pensée sociopolitique
“Like another St Basil”: Astronomy, Orthodox Apologetics and Anticommunism in Twentieth-Century Greece
No full textThis article investigates the ideological instrumentalisation of astronomy within twentieth-century Greece, centring on the work of Dimitrios Kotsakis (1909–1986) and, secondarily, Stavros Plakidis (1893–1991). The study demonstrates how Greek astronomers functioned as active agents, reframing scientific practice to serve specific apologetic and political agendas. By recontextualising pre-existing antimaterialist discourses, these figures perpetuated an ideological struggle against materialism and socialism that long predated the geopolitical Cold War, but which contributed to it. Ultimately, the article argues that Kotsakis and his milieu successfully synthesised disparate intellectual fields – scientific, religious and political – to wage what was essentially a Cold War anticommunist crusade, yet one deeply rooted in a distinctively Greek context
Experimental evaluation of Haplosporidium pinnae DNA detection and degradation under semi-controlled conditions
No full textThe fan mussel Pinna nobilis is one of the most endangered marine species in the Mediterranean Sea, having suffered mass mortality events driven primarily by the haplosporidian parasite Haplosporidium pinnae. To support the conservation of this critically endangered bivalve, the development of reliable, non-invasive detection methods is essential. Here, we tested the persistence of H. pinnae DNA in seawater under semi-controlled aquarium conditions through two filtration experiments. In the first experiment, seawater was enriched with parasite DNA from a live infected individual prior to its removal, whereas in the second experiment, enrichment included post-mortem release. Water samples were collected over several weeks and tested using end-point PCR and real time PCR assays targeting H. pinnae. Parasite DNA was detectable for up to 18 days in the live-infected experiment and 15 days in the post-mortem experiment. Detection success depended strongly on amplicon size, with shorter fragments persisting longer than larger ones. Real-time PCR also revealed different degradation dynamics between the two experiments, suggesting variation in the initial DNA load and release mechanisms. These results provide an empirical baseline for understanding the persistence of H. pinnae DNA in seawater. Although environmental variability in open waters may shorten detection windows, our findings demonstrate that eDNA remains detectable long enough to inform monitoring efforts. From a conservation perspective, eDNA assays could help identify H. pinnae-free refugia and support proactive strategies for safeguarding surviving populations of P. nobilis across the Mediterranean
Genetic structure and connectivity of the critically endangered deep-sea octocoral Isidella elongata: implications for marine biodiversity conservation in the Mediterranean Sea
No full textThe protection of the Vulnerable Marine Ecosystem identified by the presence of the critically endangered bamboo coral Isidella elongata has been recognized as an urgent task. Although some research has focused on the spatial distribution of this species, there is no information available on its connectivity and genetic structure. This is the first study to examine the genetic diversity pattern and inter-population connectivity of I. elongata at the Mediterranean scale. The DNA-based approach for assessing the genetic diversity of 33 I. elongata samples collected in six different areas involved two mitochondrial markers (COI and MutS) and one nuclear marker (ITS2). Molecular results confirmed that all samples belonged to I. elongata and showed a scarce level of intra- and inter-population mtDNA differentiation, whereas nuDNA data revealed genetic structuring. Furthermore, a Lagrangian model (forward-in-time simulations) was used to investigate the species larval connectivity under different sea current conditions. Our results suggest the presence of persistent pathways, supporting the self-sustaining nature of the populations, especially in the central Mediterranean Sea. This study identifies the main corridors of connectivity for I. elongata in the Mediterranean Sea, highlighting the importance of including such information in the implementation of fishery management measures
Distribution, population structure and life cycle of the Mediterranean endemic Laminaria rodriguezii (Laminariales, Phaeophyceae)
No full textLaminaria rodriguezii is a rare deep-water kelp species, endemic to the Mediterranean Sea, known in only 19 locations, 5 along the Eastern Provence and 14 in Corsica (French coasts). Populations are found at depths ranging from 48 to 100 m; the oldest record dates back to 1954. This study aims to better understand its distribution, biology, and ecology by analyzing recent data from in situ observations and sampling. In July 2019, a population at Magaud Bank (France) was studied at 75 m depth. A total of 154 individuals were collected in quadrats, showing an average density of 15.7 ± 2.2 individuals per m2 (mean ± SE). The population consists mostly of small blades, with 80% measuring < 40 cm in total length. The blades generally have a single lobe, corresponding to the year 2019, but sometimes 2 to 3 superimposed lobes, corresponding to the growth of the years 2018 and 2019 respectively. Lobe density ranged from 6 to 84 lobes per m2, and the dry mass (DM) varied from 24 to 1160 g DM m-2. A small percentage (17%) of individuals bore small, mostly released sori on the 2018 lobes, and some blades showed signs of herbivory (7%) and breakage (44%). In culture, we verified the typical heteromorphous haplodiplontic life cycle of Laminaria species, with microscopic dimorphic male and female gametophytes. In addition, we showed that vegetative sporophyte reproduction is possible from haptera and stolons. Except for 7 locations (in Corsica) that were not examined, all the French historical populations are still present, and we propose a Least Concern IUCN status for the species. Considering their resistance to the few disturbances likely to threaten the species (mainly fishing using tremail nets), proposals for conservation measures along the French coast are discussed
Harmony as an Ideal: A Proposal for the Further Development of Heraclitus’ Approach
No full textIn the study that follows, one might find several elements that, building on the concept of Heraclitean Harmony, move it a step further. This is especially notable considering that Heraclitus himself did not seem inclined to assign a more specialized meaning to the notion of Harmony. In particular, as Karl Jaspers observes, Heraclitus does not explicitly explain – at least in the surviving fragments – either the precise way in which opposites are connected (or united) with each other, or in what exact sense one might speak of a unity of opposites. Nor does he attempt to construct a “logic of oppositions” (a dialectic); rather, he simply starts from the grand vision of that which exists everywhere as the One and the Same. Besides, Heraclitus never even raised the question of how a synthesis – as opposed to a mere unity – of opposing forces might be achieved, for example, by envisioning “noble competition/fair play” as a harmonization of war and peace. Instead, these reflections possess in this study a primarily autonomous philosophical character, which – taking Heraclitean thought as their starting point – explore Harmony as an ideal for contemporary humanity. This ideal, according to the author, is based on the idea that each opposite contains elements useful to the mind (advantages) as well as harmful to it (disadvantages). The advantages of the one opposite are the disadvantages of the other. Hence, if one desires to attain the maximum advantages of a situation and/or the possible minimum disadvantages, one has to combine the opposites, to balance them properly and thus achieve harmony. Externally, this balance finds its expression in the form of ideals, such as justice, which is the balance between tolerance and severity
Investigation of Bacteriocin and Probiotic Properties of Lactic Acid Bacteria from Pastrami
No full textThe aim of this study was to determine the microbiological quality, LAB profile, phylogenetics of Lactobacillaceae and bacteriocin synthesis potential of pastrami isolates produced in Turkey, Kayseri. The probiotic properties of bacteriocinogen strains were investigated in the second stage of the research. To identify the isolates, MALDI-TOF MS and 16S rRNA sequence analysis methods were used. The bacteriocinogenic properties of the strains were evaluated both phenotypically, using the well diffusion method, and at the gene level, using conventional and RT-PCR. To control the stability of cell-free supernatants of bacteriocinogen strains, tolerance tests for enzyme, temperature and pH were performed. To evaluate the probiotic properties of the strains, we investigated their tolerance to gastric juice and bile salts, susceptibility to antibiotics, and ability to synthesize EPSs. The identification process revealed that the dominant species in pastrami was Latilactobacillus sakei. Based on the analyses performed, it was determined that 15 strains (14.56%) exhibited phenotypic antimicrobial activity against at least one of the selected indicator bacteria. Five strains were found to be positive for at least one of the sakacin P and sakacin Q synthesis genes on molecular analysis, which were confirmed by sequence analysis. Cell-free supernatants of bacteriocinogen strains were found to be tolerant of low pH and different temperature conditions. In conclusion, it has been determined that the Latilactobacillus sakei 2 and Latilactobacillus curvatus 48 strains have significant potential in terms of probiotic and starter culture properties