Distance Education in Chemistry during the Epidemic Covid-19

During the epidemic Covid-19, in most of the countries schools of all grades and univesities had to face a long period of closure without interrupting the educational mission. Distance education, which has been introduced first in UK in the Nineteen century as “correspondence learning” and then in USA and Australia, with the institution of “Open Universities” (i.e. MOOC and e -learning platforms), became the only way to guarantee the continuity in teaching during the pandemic Covid - 19. The present contribution is a short overview of the literature about limits and advantages of distance education of chemistry, in particular at high school and university levels, with a focus on the experiences and peculiarities of the distance education in the period of the Covid-19 emergency

STEAM Project-Based Learning Activities at the Science Museum as an Effective Training for Future Chemistry Teachers

Non-formal learning environments, such as science museums, have a fundamental role in science education and high potentialities as ideal contexts for science teachers’ training. These aspects have been analyzed and reported in several recent works mainly focused on students’ perception of science and increased engagement towards scientific disciplines. In this work, a project-based learning methodology optimized and experimented in the frame of a pre-service chemistry teachers’ course at the University of Pisa (Italy), during the last eight years, involving in total 171 participants, is presented. This educational project has several distinctive features related to the STEAM philosophy, with a high level of multi-disciplinarity and creativity. Most of the laboratories and chemistry-centered activities were conceived, planned and carried out by the future chemistry teachers in non-formal contexts, such as science museums. A case study based on a series of non-formal laboratories designed by a group of students during their training in the academic year 2018–2019 and performed in a science museum is reported and examined in details. In this paper, all steps of the STEAM project-based learning methodology are described underlining the main learning outcomes and cognitive levels involved in each step and the relevant methodologies proposed during the training course and adopted in the project. The effectiveness of this pre-service teachers’ training methodology is finally discussed in terms of participants’ motivation and interest towards the course’s content, students’ final judgment of their training experiences and, in particular, of the STEAM project-based learning activities. From the students’ feedbacks and final assessment, the role of the non-formal context in teaching and learning chemistry and the efficacy of developing educational activities related to current and real-life chemistry-centered topics emerged as very positive aspects of the proposed approach

Digital Tool for the Analysis of UV–Vis Spectra of Olive Oils and Educational Activities with High School and Undergraduate Students

UV–vis absorption spectroscopy is one of the most accessible spectroscopic techniques at the high school educational level, and it is usually introduced in analytical chemistry courses due to its high versatility and to the wide range of applications in many fields of chemistry. Within this framework, we have developed an easy-to-use “simulation tool” to identify and quantify the main pigments in a relatively complex food matrix, such as olive oil and seeds’ oils. This digital software, freely available, can be used by high school students and first-year undergraduate students to analyze the UV–vis absorption spectrum of olive oils recorded in the bulk without any chemical treatment. In this paper, we are reporting the basic principles of the spectroscopic method and the way to use the “simulation tool” with several examples and explanations that are useful for students and teachers. In the second part of the paper, several examples of activities about the chemistry of olive oil, realized with the fifth classes’ students of a high school technical institute (K–12 level) and undergraduate students of an introductory course in spectroscopy in the second year of the Chemistry Degree Course, are reported. These activities were performed partially face-to-face and partially in distance learning mode during the COVID-19 pandemic. The main learning outcomes, methodological issues, and students’ feedback resulting from these experiences are reported and commented on, showing the potential of the simulation tool for educational purposes

Racconto, fabulazione e l’ambiguità del reale ne La Settimana bianca di Emmanuel Carrère/Claude Miller (1995-1998)

Emmanuel Carrère’s La Classe de neige (1995), a watershed publication in his career as a novelist due to its partial departure from the field of fiction, is a complex and multifaceted work that leads to a meta-linguistic reflection on the very function of narration, reception, and the power of storytelling. Narration, as a device that elicits questions of perception and stages the spectres of the subconscious, is not only the centre of the character dynamics, but in this case, is also key to the solution of the story’s mystery. This article will analyse how a classical mystery story can be understood as a reflection of the symbolic functions of narration; a concept manifest in Claude Miller’s 1998 film adaptation of Carrère’s text. In Miller’s La Classe de neige (1998) the viewer is shown a reality that is totally dominated by the protagonist’s point of view, as they enter his imaginary universe built on questionable tales staged in the film through violent visual inserts. This article will therefore explore how both the literary and the filmic work effectively operate on the boundaries between the real and subjective in their narration, particularly when the latter has to deal with key plot points that remain both enigmatic and inaccessible

Pigments in Extra‐Virgin Olive Oil: Authenticity and Quality

Pigments, divided into carotenoids and chlorophyll derivatives, are responsible for the colour of extra‐virgin olive oil (EVOO). The concentration of pigments in EVOO depends on several factors, such as the maturity of olives before oil production, the cultivar and the geographic origin of olives. Pigments naturally degrade in olive oil (OO) during storage, and they may decompose due to light, temperature and oxygen exposure. The nature and concentration of pigments in EVOOs are different from seed oils, and this is a base of their use to reveal oil treatments and sophistication. In this chapter, the analytical methods, mainly chromatographic and spectroscopic, applied to identify and quantify pigments are overviewed. In particular, the applications of these methods to check the authenticity and the quality of extra‐virgin olive oil are discussed

Complessità sociale e forme contemporanee di razzismo

EnThe article investigates the issue of racism as a rapidly evolving social and cultural phenomenon while retracing its origins and major transformations. From the classic forms of scientific racism to the most recent manifestations of so-called cultural racism, the phenomenon has adapted to the various historical, economic and cultural contexts, and it is still present, in contemporary Western democracies, in more ambiguous and therefore more insidious forms. That is why education plays an increasingly important role in the development of anti-racist thoughts and behaviour; it has proven to be a tactical tool for social change. Intercultural education, in particular, tends to promote a critical view of ethnocentrism by taking diversity as a true theoretical and identity paradigm. For this reason it is decisive in the fight against and prevention of racism, especially when it is not only aimed at specific social groups, but when it calls into play all those involved in the teaching and learning process.ItL'articolo indaga la questione del razzismo inteso come un fenomeno sociale e culturale in rapida e continua evoluzione, e ne ripercorre le origini e le principali trasformazioni che lo hanno attraversato. Dalle forme classiche di razzismo "scientifico" fino alle manifestazioni più recenti di razzismo culturale cosiddetto differenzialista, il fenomeno si è adattato ai vari contesti storici, economici e culturali, ed è ancora presente, nelle democrazie occidentali contemporanee, in forme più ambigue e per questo più insidiose. Ecco perché l'educazione ricopre un ruolo sempre più centrale nella costruzione di un pensiero e comportamento antirazzisti, e si conferma uno strumento strategico di cambiamento culturale e sociale. L'educazione interculturale, in particolare, tende a promuovere uno sguardo critico verso l'etnocentrismo assumendo la diversità come vero e proprio paradigma teorico e identitario, e per questo è determinante nella lotta e nella prevenzione del razzismo, soprattutto laddove non è rivolta solo a gruppi sociali specifici, ma coinvolge tutti i soggetti impegnati nei processi di insegnamento e di apprendimento

Pigments in extra virgin olive oils produced in different mediterranean countries in 2014: Near UV-vis spectroscopy versus HPLC-DAD

Carotenoids and chlorophyll derivatives play a key role in Extra Virgin Olive Oils (EVOOs). Many factors, such as cultivar, geographic origin, maturity of olives, climate and storage conditions, influence the pigments’ content. The quantification of pigments is usually done by chromatographic techniques. However, recent works evidenced the potentialities of UV-visible-related methodologies. In this research, a selection of EVOO samples produced from olives harvested at the beginning of November 2014 in Greece, Tunisia, Italy and Spain, was investigated in terms of pigments by means of two methods. The first one is a recent approach based on the mathematical treatment of near UV-vis absorption spectra of olive oils to quantify in a fast, cheap and non-destructive way four main pigments, namely b-carotene, lutein, pheophytin A and pheophytin B. The second one is a more standard HPLC-DAD method. From the comparison between the two methods, we can conclude that the new near UV-vis approach gives reliable results, with good precision and high reproducibility. Pigments quantified by these two methods in EVOOs produced in four countries from different cultivars are analyzed by principal component analysis (PCA). Results indicate that pigments can be correlated to several factors such as ripeness stage, geographic origin and cultivars

Depth Profile of Optically Recorded Patterns in Light-Sensitive Liquid Crystal Elastomers

We investigated nonlinear absorption and photobleaching processes in a liquid crystal elastomer (LCE) doped with light-sensitive azobenzene moiety. A conventional one-dimensional holographic grating was recorded in the material with the use of two crossed UV laser beams and the angular dependence of the diffraction efficiency in the vicinity of the Bragg peak was analyzed. These measurements gave information on the depth to which trans to cis isomerisation had progressed into the sample as a function of the UV irradiation time. Using a numerical model that takes into account the propagation of writing beams and rate equations for the local concentration of the absorbing trans conformer, we computed the expected spatial distribution of the trans and cis conformers and the shape of the corresponding Bragg diffraction peak for different irradiation doses. Due to residual absorption of the cis conformers the depth of the recording progresses logarithmically with time and is limited by the thermal relaxation from the cis to trans conformation.Comment: 19 pages (incl. figs), 6 figure

Introduction to Light Properties and Basic Principles of Spectroscopy at the High-School Level: A Pilot Study

Spectroscopy is the basis of many applications in chemistry; however, the basic principles of light, light–matter interaction, and the operation of spectrophotometers are rarely present in chemistry curricula at the high-school level, or they are only briefly introduced to students before focusing on analytical chemistry applications. In this work, we report the results of a study conducted over several years, aimed to design, optimise, and put into practice a didactic sequence on light phenomena such as reflection, refraction, interference, diffraction, and light dispersion, as well as the basic principles of ultraviolet–visible spectroscopy and spectroscopic instruments. Difficult concepts of light phenomena and related topics were deeply investigated, focusing on the best ways to teach them to high-school students in the framework of the content-specific components identified in the topic-specific pedagogical content knowledge theoretical model. Inquiry-based learning and interactive STEM laboratory activities were combined with a historical epistemological teaching method. Short introductory videos were also recorded to help students during the remote lessons in the COVID-19 pandemic period. In this paper, we report and discuss the research strategy used in order to design and implement the sequence of educational activities, leading to a final optimised didactic sequence that was tested in a pilot study. The main results were obtained from the experimentation with several classes in two high-school technical institutes with a chemistry and material sciences curriculum, along with a group of undergraduate students during the first part of an introductory course on molecular spectroscopy

La diversità nelle narrazioni seriali contemporanee. Un’analisi critica dei processi di incorporazione e immunizzazione

The article investigates how the media representations of diversity have changed in the last few decades. Nowadays the question of otherness no longer seems to have a marginal role but, on the contrary, has fully entered into the mainstream and it’s at the centre of audiovisual narratives. Diversity (be it religious, cultural, gender-related, or specifically associated with the colour of the skin, or with disability) is, indeed, placed more and more into the foreground, in some cases as the cornerstone of representations that envisage, eventually, a reconciliation of conflicts, or, in other cases, as a complex element that make relationships complex and remains open to ambiguity and interrogation. Through the case study of a popular contemporary television series, this article analyzes how diversity can be more or less made complex, even within mainstream discourses and contexts. The analysis of the processes of incorporation, normalization and questioning diversity suggests a use of the audiovisual language in the formative context not only in order to educate to differences, but also to deconstruct the discourse itself that, often through the politically correct, tends to neutralize the real subversive effect inherent in the institutional instances