375 research outputs found

    An Experience on Environmental Education based on Respect-Reduce-Reuse-Recycle in a Village Primary School in the Marche Region, in Italy

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    T he importance of environmental educatio n is widely recognized worldwide: an important objective is that the citizens are accustomed to apply the best available practices in their life , while ask ing the administration and the government to gradually enforce measures lead ing to a reduction of the environmental impact and to a more sustainable lifestyle. This requires a formation starting at an early age: however, in Italy the relevant indications from the National Curriculum are still limited and do not suggest explicitly the performance of any pr actical activity , tailored on the specific school setting . This inadequacy of the Curriculum becomes particularly apparent in cases where other concerns are present, for example the areas in the Marche region affected by the 2016 earthquake : here, the need to resum e a day by day routine put a kind of \u201cdamper\u201d on other questions, such as environmental issues . This had an effect also i n children\u2019s life on this question, school needs to take a stand , which is the objective of this study . This work concerns an approach to environmental education in a multi classes primary school context (age 6 10) in a small village school, located in the Central Apennine in Italy. This is performed through an experience carried out by investigating the behavior towards waste p roduction of the community, as perceived by children at school. It is therefore articulated through the application of 4R (Respect, which encompasses Reduce, Reuse and Recycle) applying and extending the indications from the Italian National Curriculum. Th e project leads also to an experience of self production of objects by the use of waste, to improve their awareness of the possibilities included in their upcycling. Feedback on the experience is finally acquired from the children and discussed, especially in the sense of creating future citizens with a more sensible and reasonable behavior towards the environment and leading possibly to zero waste strategies in their family and work setting. The data were analy z ed using thematic analysis and different them es about waste production were singled out

    Euplotes pheromones

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    Species of Euplotes secrete protein signals (pheromones) in relation with their mating-type mechanisms of self-nonself recognition. Significant numbers of these pheromones have been characterized to varied extents of structural complexity in E. raikovi, E. nobilii, and E. octocarinatus. In every case, they form species-specific families of structurally homologous, cysteine-rich proteins. In E. raikovi, these proteins have been shown to share a common architecture based on a three-helix bundle, that permits them to bind to cells in competition with one another and elicit varied, context-dependent responses

    Structural characterization of En-1, a cold-adapted protein pheromone isolated from the Antarctic ciliate Euplotes nobilii.

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    The second of two diffusible cell signal proteins (pheromones) purified from a wild-type strain of the Antarctic ciliate, Euplotes nobilii, has been determined by automated Edman degradation of the whole molecule and peptides generated by its chymotryptic digestion. The proposed sequence of 52 amino acids of this new pheromone, designated En-1, is: NPEDWFTPDT10CAYGDSNTAW20TTCTTPGQTC30YTCCSSCFDV40VGEQACQMSA50QC. In common with the previously determined 60-amino-acid sequence of the other pheromone, En-2, it bears eight cysteines in conserved positions (presumably linked into four conserved intrachain disulfide bonds), and physicochemical features of potential significance for cold adaptation, such as a reduced hydrophobicity, an increased solvent accessibility, and an improved local backbone flexibility. However, En-1 diverges from En-2 for having evolved a threonine cluster in the place of a glycine cluster to apparently make more flexible a region that is likely functionally important

    Structural characterization of a protein pheromone from a cold-adapted (Antarctic) single-cell eukaryote, the ciliate Euplotes nobilii

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    Free-living species of ciliated Protozoa control their vegetative (mitotic) proliferation and mating (sexual) processes by diffusible, cell type-specific protein signals (pheromones). One of these molecules, designated En-2, was isolated from a species, Euplotes nobilii, living in the stably cold marine waters of Antarctica, and its complete amino acid sequence of 60 residues was determined by automated Edman degradation of the whole protein and peptides generated by trypsin digestion. The proposed sequence is : DIEDFYTSETCPYKNDSQLA20- WDTCSGGTGNCGTVCCGQCF40SFPVSQSCAGMADSNDCPNA60. The En-2 structure appears to be characterized by an adaptive insertion of a glycine-rich motif potentially capable to confer more flexibility to a functionally critical region of the molecule

    Natural function and structural modification of climacostol, a ciliate secondary metabolite

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    The review highlights the main results of two decades of research on climacostol (5-[(2Z)-non-2-en-1-yl]benzene-1,3-diol), the resorcinolic lipid produced and used by the ciliated protozoan Climacostomum virens for chemical defense against a wide range of predators, and to assist its carnivorous feeding. After the first studies on the physiological function of climacostol, the compound and some analogues were chemically synthesized, thus allowing us to explore both its effect on different prokaryotic and eukaryotic biological systems, and the role of its relevant structural traits. In particular, the results obtained in the last 10 years indicate climacostol is an effective antimicrobial and anticancer agent, bringing new clues to the attempt to design and synthesize additional novel analogues that can increase or optimize its pharmacological properties

    Chemical defence by sterols in the freshwater ciliate Stentor polymorphus

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    Heterotrich ciliates typically retain toxic substances in specialized ejectable organelles, called extrusomes, which are used in predator-prey interactions. In this study, we analysed the chemical defence strategy of the freshwater heterotrich ciliate Stentor polymorphus against the predatory ciliate Coleps hirtus, and the microturbellarian flatworm Stenostomum sphagnetorum. The results showed that S. polymorphus is able to defend itself against these two predators by deploying a mix of bioactive sterols contained in its extrusomes. Sterols were isolated in vivo and characterized by liquid chromatography-mass spectrometry (LC-MS), and nuclear magnetic resonance (NMR), as ergosterol, 7-dehydroporiferasterol, and their two peroxidized analogues. The assessment of the toxicity of ergosterol and ergosterol peroxide against various organisms, indicated that these sterols are essential for the effectiveness of the chemical defence in S. polymorphus

    Design of pressure-sensitive adhesive suitable for the preparation of transdermal patches by hot-melt printing

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    This work aimed to design low-melting pressure sensitive adhesives and to demonstrate the feasibility of the preparation of (trans)dermal patches by hot-melt ram extrusion printing. This approach allows defining both the geometry of (trans)dermal patch and the drug strength easily according to patient needs. The preparation steps are the mixing of a poly-ammonium methacrylate polymer (i.e. Eudragit RL and RS) with a suitable amount of plasticizer (triacetin or tributyl citrate) and drug (ketoprofen or nicotine), the melting in the ram extruder, and the printing on the backing layer foil. The formulations were characterized in terms of rheological and adhesive properties, in vitro drug release and skin permeation profiles. The (trans)dermal patches made of Eudragit RL or Eudragit RS plasticized with the 40% triacetin could be printed at 90 \ub0C giving formulations with suitable adhesive properties and without cold flow after 1 month of storage at 40 \ub0C. Furthermore, the overall results showed that the performances of printed (trans)dermal patches overlapped those made by solvent casting, suggesting that the proposed solvent-free technology can be useful to treat cutaneous pathologies when the availability of (trans)dermal patches with size and shape that perfectly fit with the skin area affected by the disease improves the safety of the pharmacological treatment
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