86,578 research outputs found
Economia circular, responsabilidad social, formacion para la sostenibilidada: cuestiones emblematicas
No full textLos escenarios de la crisis económica y de la degradación medioambiental están estrechamente relacionados: las inversiones en la sostenibilidad y en la seguridad constituyen un potencial empuje para el restablecimiento y el crecimiento. La cuestión educativa, que a través la convivencia actual, designa las ambigüedades de una concepción de progreso voraz y rapaz, sin respeto para los recursos humanos y naturales. Entre relevantes diferencias semánticas, los términos emergencia, desafío, necesidad se refieren a la importancia crucial de aquel bien colectivo que es la educación. En esta perspectiva es susceptible de análisis crítica la Corporate Social Responsibility, como elección estratégica por parte de la empresa. El discurso pedagógico está llamado a considerar la implicación formativa de la organización, la dimensión de planificación de la noción de la responsabilidad en vista de la construcción de la sociedad civil y del cumplimiento integral del hombre
Formare i giovani per edificare il futuro, tra ecologia integrale e transizione ecologica
No full textLa complicata situazione attuale, che coinvolge l’ambiente in diverse forme, è dovuta ad una erronea idea di progresso tecnologico ed economico oltre ad un dilagante sfruttamento indiscriminato delle risorse e all’incapacità di cogliere la necessità di agire in modo rispettoso verso l’altro, lato sensu. Di fronte alla criticità della salute del pianeta, ciascuno è chiamato a conoscere
quanto sta accadendo e ad affrontare le sfide contemporanee con tenacia e lungimiranza per migliorare le condizioni delle persone e degli ecosistemi. È il senso di responsabilità verso le generazioni future che richiede una conversione ecologica globale e sollecita le scienze, in modo peculiare la pedagogia, a riflettere sul rapporto tra educabilità e tecnologia, ricerca del benessere e autenticità degli stili di vita
Tolerance and accumulation of thallium in three geographically distant populations of Biscutella laevigata L. subsp. laevigata Mant.
No full textPlantlets of two metallicolous and one nonmetallicolous populations of Biscutella laevigata subsp. laevigata were grown hydroponically for eight days at increasing concentrations of Tl: control, 1, 10 or 100 ppm Tl. Population tolerance to excess Tl was evaluated using a root elongation test. Tl concentration in shoots and roots was used as additional evaluation criteria. Based on the indicators used we confirmed the tolerance of population from Les Malines (F) (Lem) and demonstrate the tolerance of population from Cave del Predil (I) (Cap) and its capacity to accumulate Tl in shoots and roots (up to 28,745 mg kg-1 in shoots). Moreover the genetic structure was investigated using Amplified Fragment Length Polymorphism (AFLP) markers. All the results indicate that Cap population property of tolerance and accumulation of Tl is not a mere environmental effect but has also genotype bases and it is probably a constitutive and adaptive trait
Alta Formazione per l'ecologia integrale. Green Jobs, imprese, educazione
No full textGli ultimi decenni sono stati connotati da fenomeni che hanno posto in luce temi fondamentali per la custodia del pianeta; green economy e sostenibilità sono concetti che hanno assunto una considerevole popolarità e attirato una crescente attenzione da parte dell’opinione pubblica e della ricerca scientifica. Sviluppo umano e ambiente, valori e governance politica sono strettamente connessi. Una coscienza ecologica costituita sulla speranza per il futuro delle società ridefinisce il progresso che, per essere autentico, dev’essere ‘integrale’. La pedagogia nel considerare i contesti educativi e formativi, avvalora la categoria del lavoro, quale occasione in cui l’adulto può esprimere la propria creatività e generatività sotto forma di idee, azioni, prodotti e l’organizzazione quale spazio di promozione dell’humanum e della sostenibilità. Per l’alta Formazione promuovere competenze “verdi” deve significare sostenere lo sviluppo di professionalità che mettano a tema la qualità della vita, il rispetto dell’ambiente in ogni sua declinazione per un benessere duraturo. La formazione si pone al servizio dell’umano e dell’ambiente come strumento per educare ad una nuova fraternità
Field-Effect Controllable Metallic Josephson Interferometer
No full textGate-tunable Josephson junctions (JJs) are the backbone of superconducting classical and quantum computation. Typically, these systems exploit low-charge-concentration materials and present technological difficulties limiting their scalability. Surprisingly, electric field modulation of a supercurrent in metallic wires and JJs has been recently demonstrated. Here, we report the realization of titanium-based monolithic interferometers which allow tuning both JJs independently via voltage bias applied to capacitively coupled electrodes. Our experiments demonstrate full control of the amplitude of the switching current (Is) and of the superconducting phase across the single JJ in a wide range of temperatures. Astoundingly, by gate-biasing a single junction, the maximum achievable total Is is suppressed down to values much lower than the critical current of a single JJ. A theoretical model including gate-induced phase fluctuations on a single junction accounts for our experimental findings. This class of quantum interferometers could represent a breakthrough for several applications such as digital electronics, quantum computing, sensitive magnetometry, and single-photon detection
Is an Hyperloop System A Megaproject? An Italian Case Study Between the Cities of Milan and Rome
No full textThis paper analyzes the potential of implementing an Hyperloop transportation system between Milan and Rome in Italy, exploring its feasibility as a megaproject. The two cities, about 530 km apart, are home to some of the country’s largest institutions and multinational companies, making them important generators and attractors of mobility demand . The Hyperloop system, introduced by Elon Musk in 2013, utilizes magnetic levitation and a vacuum tube to transport passengers and goods at speeds exceeding 1000 km/h. Given the scale and complexity of such a project, it can be classified as a megaproject, which involves significant capital investment, multiple stakeholders, and substantial socio-economic impacts. The study includes a cost analysis of both CAPital EXpenditure (CAPEX) estimated around € 20.5 billion and OPerational EXpenditure (OPEX) estimated around 187 million €/y (euro/year) and examines different revenue scenarios. The first scenario (Maximum revenue scenario) maximizes revenue for the infrastructure operator, the second (Maximum transport demand) maximizes demand and therefore the service offered, and the third (Elon Musk scenario) sets the ticket price at €20. Among the scenarios analyzed, it was found that the first profits from the Hyperloop would be generated starting from the 21st year, with a profit of €2.5 billion beginning in the 48th year, assuming maximum revenue. The results highlight that, despite the high initial costs, the system could provide long-term economic benefits, particularly through a public-private partnership model. The conclusion underscores the potential of the Hyperloop to revolutionize mobility between Milan and Rome, making it a competitive alternative to current transportation options. Future research could further explore cost optimization and sustainability improvements
NUCLEAR AND PLASTID SEQUENCES FOR IDENTIFICATION OF SPECIES OF FLOWERING PLANTS (DNA BARCODING)
No full textElectron Cooling with Graphene-Insulator-Superconductor Tunnel Junctions for Applications in Fast Bolometry
No full textElectronic cooling in hybrid normal-metal-insulator-superconductor junctions is a promising technology for the manipulation of thermal loads in solid-state nanosystems. One of the main bottlenecks for efficient electronic cooling is the electron-phonon coupling, as it represents a thermal leakage channel to the phonon bath. Graphene is a two-dimensional material that exhibits a weaker electron-phonon coupling compared to standard metals. For this reason, we study the electron cooling in graphene-based systems consisting of a graphene sheet contacted by two insulator-superconductor junctions. We show that, by properly biasing the graphene, its electronic temperature can reach base values lower than those achieved in similar systems based on metallic ultrathin films. Moreover, the lower electron-phonon coupling is mirrored in a lower heat power pumped into the superconducting leads, thus avoiding their overheating and preserving the cooling mechanisms. Finally, we analyze the possible application of cooled graphene as a bolometric radiation sensor. We study its main figures of merit, i.e., responsivity, noise equivalent power, and response time. In particular, we show that the built-in electron refrigeration allows reaching a responsivity of the order of 50nA/pW and a noise equivalent power of order of 10-18WHz-1/2 while the response speed is about 10 ns corresponding to a thermal bandwidth in the order of 20 MHz
Preliminary Technical Analysis of a Hyperloop Line for Freight Transport: Case Study from Italy
No full textThe issue of environmental sustainability in freight transport has become increasingly important, and the use of road transport has resulted in increased air pollution. To address this, the hyperloop system is proposed as a sustainable alternative for transporting large quantities of goods in a short time. This work proposes a methodology for pre-sizing a hyperloop system dedicated to freight transport. An iterative model is used to compare different scenarios for maximizing the quantity
of transportable goods and optimizing the power absorbed by the system. The terminal characteristics are defined based on the handling operations for loading and
unloading goods and their respective times. The scenarios developed consider the number of containers per capsule, speed, and acceleration, and identify the solution
that maximizes the quantity of goods transported and optimizes the power absorbed by the system. The methodology is applied to a case study in Italy for transversely
connecting northern Italy and the European TEN-T corridors starting from the Venice interport and connecting Verona, Piacenza, Mortara, and Orbassano. The proposed methodology can help in designing a sustainable and efficient hyperloop system for freight transport
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