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690 697 27 3 ; S ; [EN] In Physics, many quantities are vectors, and their use requires typical operations such as addition, subtraction, scalar multiplication, scalar product (dot product), vector product (cross product), and scalar triple product. This is a very basic topic in all General Physics courses for Engineering degrees. However, we have detected that some students lack a deep understanding of vector operations and their properties. In this study, we present a virtual laboratory (developed using the tool Easy Java Simulations) for the study and understanding of these topics. The user can introduce the components of the input vectors and gets a three-dimensional representation, which can be scaled and rotated for better visualization. Any of the aforementioned operations can be selected, and the result is shown both numerically and graphically. The user can also modify any represented vector. In this way, the virtual lab provides a real-time visualization of how the change affects the result. The possibility of limiting the changes to either magnitude or direction is also included. The efficiency of the virtual laboratory has been tested analyzing the results obtained in two groups of students (virtual laboratory vs traditional resources). A satisfaction survey has been also carried out. Salinas Marín, I.; Gimenez Valentin, MH.; Cuenca Gotor, VP.; Seiz Ortiz, R.; Monsoriu Serra, JA. (2019). Design and evaluation of a three-dimensional virtual laboratory on vector operations. Computer Applications in Engineering Education. 27(3):690-697. https://doi.org/10.1002/cae.22108 Vidaurre, A., Riera, J., Giménez, M. H., & Monsoriu, J. A. (2002). Contribution of digital simulation in visualizing physics processes. Computer Applications in Engineering Education, 10(1), 45-49. doi:10.1002/cae.10016 Depcik, C., & Assanis, D. N. (2005). Graphical user interfaces in an engineering educational environment. Computer Applications in Engineering Education, 13(1), 48-59. doi:10.1002/cae.20029 Jimoyiannis, A., & ...

14 pages, 4 figures, 1 table, supplementary data https://doi.org/10.1016/j.scitotenv.2021.151359 ; The metabolism of contemporary industrialized societies, that is their energy and material flows, leads to the overconsumption and waste of natural resources, two factors often disregarded in the global ecological equation. In this Discussion article, we examine the amount of natural resources that is increasingly being consumed and wasted by humanity, and propose solutions to reverse this pattern. Since the beginning of the 20th century, societies, especially from industrialized countries, have been wasting resources in different ways. On one hand, the metabolism of industrial societies relies on non-renewable resources. On the other hand, yearly, we directly waste or mismanage around 78% of the total water withdrawn, 49% of the food produced, 31% of the energy produced, 85% of ores and 26% of non-metallic minerals extracted, respectively. As a consequence, natural resources are getting depleted and ecosystems polluted, leading to irreversible environmental changes, biological loss and social conflicts. To reduce the anthropogenic footprint in the planet, and live in harmony with other species and ourselves, we suggest to shift the current economic model based on infinite growth and reduce inequality between and within countries, following a degrowth strategy in industrialized countries. Public education to reduce superfluous consumption is also necessary. In addition, we propose a set of technological strategies to improve the management of natural resources towards circular economies that, like ecosystems, rely only upon renewable resources ; This study received Portuguese national funds from FCT (Foundation for Science and Technology) through project UID/04326/2020 and the Stimulus of Scientific Employment, Individual Support Call, 2017 (CEECIND/03072/2017). It also received funds from the Centre d'Estudis Antoni de Capmany and the Spanish government through the 'Severo Ochoa Centre of Excellence' accreditation (CEX2019-000928-S). Federico Demaria is a Serra Hunter fellow and acknowledges support from the Maria de Maeztu Unit of Excellence ICTA UAB (CEX2019-0940-M), and the projects 'EnvJustice' (GA 695446) and PROSPERA (GA 947713), both funded by the European Research Council (ERC). Claudia Ofelio is Research Associate at Hamburg University within the framework of the project CUSCO (FKZ:03F0813B). The Thermal Engineering and Energy Systems (GITSE) research group T55_20R received funds from the Aragonese Government (Department of Science, University and Knowledge Society) ; Peer reviewed