Towards a more sustainable environmentally production system for the treatment of recycled aggregates in the construction industry: An experimental study.

The reuse and recycling of construction and demolition waste is becoming an advisable choice to reduce the consumption of key raw materials and the environmental impact generated by the construction of new buildings. This study proposes the introduction of two new stages of recycled aggregate processing that allow redesigning the production process of recycled aggregates towards a more sustainable and eco-friendly system: sieving with secondary crushing and washing. Based on an experimental study, our findings show that the new stages reduce significantly the content of impurities and the water absorption of recycled aggregates, obtaining a better final product (i.e. cement mortar) for buildings. Moreover, the new final product made with treated recycled aggregates also experiences significant improvements in their physical and mechanical properties (i.e.: increased on average, 5% in flexural strength, 6% in compression strength and reduced shrinkage by 2%), in turn reducing both the costs associated with the manufacture of the new product and its environmental impact compared to other products that solely include untreated recycled aggregates. The potential economic and solid waste management implications for firms that choose to deploy the new production system depicted are also discussed.

How reactive is investment in US green bonds and ESG-eligible stocks in times of crisis? Exploring the COVID-19 crisis.

This study examines how green bonds and environmental, social and governance (ESG) stock market returns have reacted to the COVID-19 crisis in the US. Unlike the Standard and Poor's (S&P) 500 index, the response of green bonds and ESG markets to pandemic progress is nonlinear: A low (large) level of confirmed new cases of COVID-19 has a positive (negative) impact. Furthermore, the implemented containment policies (stringency measures and vaccination campaigns) are positively valued, but their simultaneous use is perceived by investors as a bad signal. Overall, our findings question the resilience of investments in green bonds and ESG markets.

The female presence in different organisational positions and performance in secondary schools: Does a woman leader function as mediator?

This study examines the relationship between female representation in different organisational positions and performance using a sample of Spanish secondary schools. These organizations have been usually depicted as 'feminised environments' although women in managerial positions are still underrepresented. Based on different theoretical approaches, we separately investigate the relationship between a greater female presence and school performance in three positions: a) as principal; b) on the management team; and c) as teachers. We also investigate if having a female leader exerts a significant mediator role on the relationship between greater female representation on the management team and teachers, respectively, and school performance. Our results reveal a positive and significant relationship between having a woman principal or a greater proportion of women teachers and school performance. However, the relationship between a high proportion of women on the management team and school performance is negative. We also find that a female principal does not play a significant role as mediator in the relationship between having a greater proportion of women on the management team and as teachers and school performance.