Osservare per valutare: la scuola primaria e la sfida del cambiamento

Il contributo pone al centro l’Ordinanza Ministeriale 172/2020, la quale introduce nella scuola primaria il giudizio descrittivo come modalità per esprimere la valutazione periodica e finale. Le novità da essa portate non si limitano a un semplice cambio “di forma” della valutazione, piuttosto ne spostano i significati e le valenze prevalenti: da una valutazione dell’apprendimento a una valutazione per l’apprendimento. Ciò richiede alle scuole di attuare processi di ripensamento e cambiamento delle pratiche progettuali e didattiche. Secondo l’Ordinanza la valutazione scaturisce da 4 dimensioni attraverso le quali è possibile conoscere il processo di apprendimento. A tale fine, assume importanza l’osservazione – abitualmente poco praticata nella scuola - da intendere come una delle necessarie strade per la raccolta di quelle evidenze utili alla redazione del giudizio descrittivo. Il contributo discute un approccio di ricerca-formazione sui temi sollecitati dall’Ordinanza, con particolare riferimento alla pratica osservativa

The Role of the Coagulation System in Peripheral Arterial Disease: Interactions with the Arterial Wall and Its Vascular Microenvironment and Implications for Rational Therapies

Peripheral artery disease (PAD) is a clinical manifestation of atherosclerotic disease with a large-scale impact on the economy and global health. Despite the role played by platelets in the process of atherogenesis being well recognized, evidence has been increasing on the contribution of the coagulation system to the atherosclerosis formation and PAD development, with important repercussions for the therapeutic approach. Histopathological analysis and some clinical studies conducted on atherosclerotic plaques testify to the existence of different types of plaques. Likely, the role of coagulation in each specific type of plaque can be an important determinant in the histopathological composition of atherosclerosis and in its future stability. In this review, we analyze the molecular contribution of inflammation and the coagulation system on PAD pathogenesis, focusing on molecular similarities and differences between atherogenesis in PAD and coronary artery disease (CAD) and discussing the possible implications for current therapeutic strategies and future perspectives accounting for molecular inflammatory and coagulation targets. Understanding the role of cross-talking between coagulation and inflammation in atherosclerosis genesis and progression could help in choosing the right patients for future dual pathway inhibition strategies, where an antiplatelet agent is combined with an anticoagulant, whose role, despite pathophysiological premises and trials' results, is still under debate

Euphorbia characias Extract: Inhibition of Skin Aging-Related Enzymes and Nanoformulation

Plant extracts have long served as important sources of bioactive compounds, and they are currently the focus of extensive research in the development of novel preventive and therapeutic strategies. However, their health benefits are often limited by low bioavailability. Nanoparticle delivery systems can represent a solution to such limitations. Euphorbia characias is a Mediterranean shrub known to have biological activities, such as inhibiting tyrosinase and showing a potential role as a skin-whitening agent. In this study, an ethanolic extract from E. characias leaves was tested for its inhibitory activity on skin-related enzymes, such as elastase, collagenase, and hyaluronidase, and for sun protection factors. Moreover, the extract was formulated in phospholipid vesicles to improve its local bioavailability and applicability. The vesicles were characterized by size, surface charge, storage stability, and entrapment efficiency. The nanoformulation was also evaluated for antioxidant activity and assayed for cytocompatibility and anti-tyrosinase activity in melanoma cells. Our findings demonstrated that the extract has a photo-protective effect and enzyme-inhibitory properties. E. characias nanoformulation was also cytocompatible and improved the extract’s activity in the cells, suggesting a potential skin application for antimelanogenic treatments and confirming the key role of nanotechnological approaches to maximize plant extract’s potentialities

Dynorphin gene expression and release in the myocardial cell.

The expression of the prodynorphin gene was investigated in adult cultured rat ventricular cardiac myocytes by using a sensitive solution hybridization RNase protection assay for the quantitative analysis of prodynorphin mRNA. Myocyte culture in high KCl resulted, after 4 h, in a marked increase in cellular prodynorphin mRNA, while a KCl treatment for 6, 12, or 24 h progressively down-regulated the levels of prodynorphin mRNA below the control value. Immunoreactive dynorphin B, a biologically active end product of the precursor, was found to be present in the culture medium in significantly higher amounts than in the cardiac myocytes. The levels of this biologically active K opioid receptor agonist significantly increased after 4 h of KCl treatment and were markedly reduced following a 24-h exposure of the cardiac myocytes to KCl. These KCl-induced effects were all abolished by cell incubation in the presence of the calcium channel blocker verapamil. In single cardiac myocytes, acute stimulation of K opioid receptors with dynorphin B or with the selective agonist U-50,488H increased the level of cytosolic calcium. This effect was abolished by the specific K opioid receptor antagonist (Mr-1452) and was not affected by the removal of calcium from the bathing medium. These results suggest that an opioid gene may influence the myocardial function in an autocrine or paracrine fashion

A structural spproach to the strength evaluation of linear chalcogen bonds

The experimental structural features of chalcogen bonding (ChB) interactions in over 34,000 linear fragments R–Ch⋯A (Ch = S, Se, Te; R = C, N, O, S, Se, Te; A = N, O, S, Se, Te, F, Cl, Br, I) were analyzed. The bond distances dR–Ch and the interaction distances dCh⋯A were investigated, and the functions δR–Ch and δCh⋯A were introduced to compare the structural data of R–Ch⋯A fragments involving different Ch atoms. The functions δR−Ch and δCh⋯A were calculated by normalizing the differences between the relevant bond dR–Ch and ChB interaction dCh⋯A distances with respect to the sum of the relevant covalent (rcovR + rcovCh) and the van der Waals (vdW) radii (rvdWCh + rvdWA), respectively. A systematic comparison is presented, highlighting the role of the chalcogen involved, the role of the R atoms covalently bonded to the Ch, and the role of the A species playing the role of chalcogen bond acceptor. Based on the results obtained, an innovative approach is proposed for the evaluation and categorization of the ChB strength based on structural data

Large-FSR Thermally Tunable Double-Ring Filters for WDM Applications in Silicon Photonics

International audience; We present the design procedure and experimental results of thermally tunable double ring resonators for integrated wavelength division multiplexing applications. A detailed analytical model specific for double rings is described, and a modified racetrack geometry using Bezier bends is used to reduce bending loss. We demonstrate devices with a free-spectral-range up to 2.4 THz ( 19 nm) around 1550 nm and nonadjacent channel rejection higher than 35 dB. The experimental results of thermally tunable double ring resonators is also presented with doped silicon integrated heaters, allowing the device to be used as a tunable filter or a switch

A Liposomal Formulation to Exploit the Bioactive Potential of an Extract from Graciano Grape Pomace

Antioxidant compounds with health benefits can be found in food processing residues, such as grape pomace. In this study, antioxidants were identified and quantified in an extract obtained from Graciano red grape pomace via a green process. The antioxidant activity of the extract was assessed by the DPPH and FRAP tests, and the phenolic content by the Folin–Ciocalteu test. Furthermore, nanotechnologies were employed to produce a safe and effective formulation that would exploit the antioxidant potential of the extract for skin applications. Anthocyanins, flavan-3-ols and flavanols were the main constituents of the grape pomace extract. Phospholipid vesicles, namely liposomes, were prepared and characterized. Cryo-TEM images showed that the extract-loaded liposomes were predominantly spherical/elongated, small, unilamellar vesicles. Light scattering results revealed that the liposomes were small (~100 nm), homogeneously dispersed, and stable during storage. The non-toxicity of the liposomal formulation was demonstrated in vitro in skin cells, suggesting its possible safe use. These findings indicate that an extract with antioxidant properties can be obtained from food processing residues, and a liposomal formulation can be developed to exploit its bioactive value, resulting in a promising healthy product

Anti-aging potential of extracts from Washingtonia filifera seeds

The aim of this study was to test the inhibitory effect of fruit extracts from Washingtonia filifera on skin aging-related enzymes. The pulp extracts did not exert a significant enzyme inhibition while seed extracts from W. filifera exhibit anti-elastase, anti-collagenase, and anti-tyrosinase activities. Tyrosinase was mildly inhibited while a stronger effect was observed with respect to elastase and collagenase inhibition. Alcoholic extracts provided better results than aqueous extracts. Among them, methanol extracts showed the prominent enzyme inhibitory activities being IC50 value for elastase and collagenase comparable and even better than the reference compound. The inhibition mode of the most active extracts was investigated by Lineweaver-Burk plot analysis. Seed extracts from W. filifera were also investigated for their photo-protective effect by Mansur equation and the antioxidant activity of W. filifera extract was evaluated in oxidative-stressed cells. To evaluate the safety of the extract, the effect on cell viability of human keratinocytes cells was analyzed. Methanol extract presented the best photo-protective effect and exerted an antioxidant activity in a cellular system with no cytotoxic effect. The overall results demonstrate that W. filifera extracts are promising sources of bioactive compounds that could be used in cosmetic and pharmaceutical preparation