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In living cells and biomimetic systems alike, multivalent ligands in solution can induce clustering of membrane receptors. The link between the receptor clustering and the ligand binding remains, however, poorly defined. Using minimalist divalent ligands, we develop a model that allows quantifying the modulation of receptor clustering by binding of ligands with any number of binding sites. The ligands, with weak binding affinity for the receptor and with binding sites held together by flexible linkers, lead to nearly quantitative clustering upon binding in a wide range of experimental conditions, showing that efficient modulation of receptor clustering does not require pre-organization or large binding affinities per binding site. Simulations show that, in the presence of ligands with five or more binding sites, an on/off clustering response follows a very small change in receptor density in the membrane, which is consistent with the highly cooperative behavior of multivalent biomolecular systems.

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To the non-specialist, the concept of geological natural hazard usually refers to natural processes affecting the geosphere that produce far-reaching and intense effects, involving significant transfers of matter and energy, in a relatively short time when compared to the human timescale. Usually, these processes are also associated with abrupt and destructive effects involving human activities and lives.From the geoscientific point of view, slower and more gradual processes, which produce small scale effects, can also pose a hazard, for example when the process results in the loss of scientific information or in the destruction of evidence of past events that cannot be reproduced, such as those related to the history of life, or when spectacular examples of particular aesthetic value are destroyed.Only widespread education and good quality communication, both rigorous and effective, can increase people's awareness and sensitivity to the need for protection of the geological heritage and for adopting geoethic attitudes. This paper presents some case studies in the Piedmont region (NW Italy) that involved students of primary and secondary schools in an active and participatory way and that represented a training opportunity for their teachers.

A geoethical approach to geodiversity allows better understanding of the value of abiotic nature and enhances its conservation and development. Our basic assumption is that even during an economical crisis, geoheritage sites can serve both public and private interests. A set of nine strategic geothematic areas were chosen to represent the geodiversity of the Piemonte region, north-western Italy, each of which is characterized by great potential for scientific studies, enhancement of public understanding of science, recreational activities, and economic support to the local communities. Specialized research teams individuated critical aspects to advance our knowledge of the geological history of the Piemonte region, through climate and environmental changes, natural hazards, soil processes, and georesources. The scientific concepts and techniques were coupled with geodiffusion actions and products: not only geosites, but also museum collections, evidence of mining and quarrying activities, science exhibitions, and nature trails. The preliminary results have allowed action plans to be developed with local partners, to assess the geoheritage management requirements. A series of investigations were carried out to improve the visual representation of the geological processes and the evolutionary scenarios. Further outcomes of the project will include didactic tools for educators, schools, and the public in general. Methods and stages of the 'PROGEO-Piemonte' research programFrom a geoethical perspective, the multidisciplinary research project known as 'PROGEO-Piemonte' (PROactive management of the GEOlogical heritage in the Article history

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The sudden event of the spread of dengue fever (or break-bone fever) that appeared for the first time in Cape Verde in 2009 revealed that inappropriate management of waste can be considered a major cause of the spread of this disease. Dengue fever is a tropical infectious disease that is caused by the dengue virus. Its vector, the mosquito Aedes aegypti, found an optimal environment for its life cycle in the context of Cape Verde, with the persistence of water in abandoned waste objects. The connection between the topics of Earth sciences and the spread of this disease is not obvious, but it was explored and illustrated in a school partnership. Activities with pupils and students provided an opportunity to investigate how some global phenomena, like climate change (with an increase in local rainfall and higher temperatures), are related to local events, such as the spread of dengue fever. Preventive strategies are conditioned by the geomorphology of the territory and by the complex relationships that connect the geosphere and the biosphere. For this reason, it is important to be aware of the risk of breaking these delicate balances, and hence activating unexpected consequences. The roles played by both partners linked knowledge about the natural dynamics of our planet with the development of appropriate behavior, thus contributing to the formation of responsible citizenship, to preserve and protect the environment. The partnership encouraged students to develop sustainable management strategies against dengue fever, and consequently against waste, actively involving them at school, at home, and in their community. In this study, we present a case study of the role of a school partnership in a complex problem, such as the spread of dengue fever and environmental pollution.