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The sustainable management of agricultural residues is a pivotal element in ensuring the sustainable development of agriculture. This is based on strategies that include the reutilization of residues as a substrate for the cultivation of economically significant mushroom species. The primary aim of this investigation is to assess the viability of utilizing two of the most prevalent agricultural residues in Ecuador as a substrate for the cultivation of hybrids within the Pleurotus genus. This assessment includes an evaluation of the nutritional and productivity parameters exhibited by the resulting mushrooms, employing multivariate statistical methodologies. The hybrid strains were developed by crossing compatible neohaplonts obtained through chemical dedikaryotization. A total of five neohaplonts of Pleurotus ostreatus as parental strain P1 and five monokaryons of Pleurotus djamor as parental strain P2 were randomly crossed in all possible combinations. Two parental hybrid strains, H1 and H2, were produced. These hybrids were cultivated using agricultural waste substrates, specifically, green banana leaves (GBL) and sugarcane bagasse (SB). Two distinct treatments or mixtures were tested: M1 (composed of 80% SB and 20% GBL) and M2 (composed of 20% SB and 80% GBL). It was found that the M1 blend promotes mushroom growth, yielding superior properties attributable to the higher proportion of nutritional content derived from sugarcane bagasse.

We introduce a field survey method to assess the conservation condition of landscapes. Using a popular rapid assessment format, this study defines observable “stressed states” identified through the use of general metrics to gauge landscape degradation. Fifteen metrics within six thematic categories were selected through a literature review and extensive field trials. Field tests on the Greek island of Samothraki show a strong correlation between a single expert’s scores and five assessor’s scores at 35 landscape sites. Only three of the metrics did not maintain a high consistency among assessors; however, this is explained by the difficulty of interpreting certain anthropogenic stressors (such as livestock grazing) in Mediterranean semi-natural landscapes with culturally-modified vegetation patterns. The protocol and proposed index, with five conservation condition classes, identified areas of excellent and good quality, and reliably distinguished the most degraded landscape conditions on the island. Uncertainties and difficulties of the index are investigated, and further research and validation are proposed. The protocol effectively goes beyond a traditional visual aesthetic assessment; it can be used both by experts and non-scientists as a conservation-relevant multi-disciplinary procedure to support a holistic landscape diagnosis. The combination of an on-site experiential survey and its simple integrative format may be useful as a screening-level index, and for promoting local participation, landscape literacy and educational initiatives.

Solar photovoltaic (PV) energy systems are one of the most widely deployed renewable technologies in the world. The efficiency of solar panels has been studied during the last few decades, and, to date, it has not been possible to displace the production of energy using crystalline silicon wafer-based technology whose efficiency has reached values around 26.1%. Moreover, using solar tracking PV systems has become a feasible alternative to increase the electric output of PV silicon technologies instead of using the conventional fixed PV installation on a flat or sloping surface. The following study has compared fixed and dual-axis sun-tracking PV panels in order to quantify the enhancement associated with the amount of energy harvested when using dual-axis tracking PV systems in the city of Manta, located in a coastal region of Ecuador. In order to carry out this study, an IoT monitoring system based on Raspberry Pi3 and Arduino platforms was used. Measurements of solar radiation (W/m2), light intensity (Lux), temperature (°C), short-circuit current (A), and open-circuit voltage (V) were taken every minute for both systems. The results prove that the dual-axis tracking PV system produces, on average, 19.62% more energy than the static PV system. These results present an 8.62% energy increase with respect to a previous study carried out in an equatorial region with similar characteristics to those of the city of Manta, where a one-axis tracking PV system was used.

Building-integrated greenery (BIG) systems, which include green roofs and green facades, are well-established nature-based solutions (NBS) with proven scientific benefits. However, initial costs and economic apprehensions stemming from potential negative outcomes act as adoption barriers. Furthermore, the lack of standardized indicators and assessment methodologies for evaluating the city-level impacts of BIG systems presents challenges for investors and policy makers. This paper addresses these issues by presenting a comprehensive set of indicators derived from widely accepted frameworks, such as the Common International Classification of Ecosystem Services (CICES) and the NBS impact evaluation handbook. These indicators contribute to the creation of a ‘sustainability factor’, which facilitates cost–benefit analyses for BIG projects using locally sourced data. The practical application of this factor to a 3500 m2 green roof in Lleida, Catalonia (Spain) demonstrates that allocating space for urban horticultural production (i.e., food production), CO2 capture, and creating new recreational areas produces benefits that outweigh the costs by a factor value of nine during the operational phase of the green roof. This cost–benefit analysis provides critical insights for investment decisions and public policies, especially considering the significant benefits at the city level associated with the implementation of BIG systems.

Higher Education Institutions are facing a challenging situation: how to introduce concepts such as Sustainability or the Circular Economy into their curricula. This study presents how to organize a Computer Reuse Program, an educational proposal for the Reuse, Repair, Refurbishment, Remanufacture and Recycling of computers into a Curriculum and a case study. The proposal is based in the Service-Learning methodology, by which students develop technical and professional skills while undertaking a project that has a direct and real impact on society. Students work on old or broken computers provided by donors, thereby acquiring technical skills. These now flawlessly functioning computers are donated to NGOs and other non-profit organizations, thus endowing the equipment with a much longer life as well as reducing e-waste, one of the fastest-growing waste streams in the world. As a case study, this paper presents the UPC Computer Reuse Program, carried out at Universitat Politècnica de Catalunya UPC-BarcelonaTech. Since the program started in 2004, some 2500 computers have been donated to 359 different organizations in 29 countries, and more than 5200 students have participated. The paper analyzes the impact of the program on society, on the reduction of e-waste, on the environment and on student awareness regarding social justice and sustainability.

(1) The amount of plastic discharges in the environment has drastically increased in the last decades negatively affecting aquatic ecosystems, societies, and the world economy. The policies initiated to deal with this problem are insufficient and there is an urgency to initiate local actions based on a deep understanding of the factors involved. (2) This paper investigates the potential of massive open online courses (MOOCs) to spread environmental education. Therefore, the conclusions drawn from the implementation of a MOOC to combat the problem of marine litter in the world are presented. (3) This work describes the activity of 3632 participants from 64 countries taking an active role presenting useful tools, connecting them with the main world associations, and defining applied action plans in their local area. Pre- and post-questionnaires explore behavioral changes regarding the actions of participants to combat marine litter. The role of MOOCs is contrasted with social media, formal education, and informal education. (4) Findings suggest that MOOCs are useful instruments to promote environmental activism, and to develop local solutions to global problems, for example, clean beaches, supplanting plastic bottles, educational initiatives, and prohibition of single-use plastic.

Various studies have investigated the business model (BM) in different dimensions. However, bibliometric analyses in this discipline are still limited. This study aims to conduct a bibliometric analysis of business model research, identifying the state of the art, trends, and other indicators by analyzing articles published on the Web of Science (WoS) platform from 2017 to 2022. The present study examines the simultaneous occurrence of publications by year, keyword trends, bibliographic coupling, analysis of co-authorship, cities, and institutions, and finds that the literature on business models rapidly expanded between 2017 and 2020. A total of 14,881 articles were obtained as samples. The present study employs VOSviewer software to analyze the data. A considerable amount of literature has been produced on BMs, but researchers have stopped developing further literature which is thought-provoking. Based on the findings of this study, it is concluded that there is a need to research BMs in different domains such as sustainability and digitalization.