Chronic heart block in dogs; a method for producing experimental heart failure

A method is described for the production of chronic atrioventricular block in dogs, by incision of the region of the bundle of His through the open right atrium during temporary caval occlusion. Exercise tolerances, chest x-ray films, electrocardiograms, phonocardiograms, cardiac outputs, intracardiac pressures, femoral pressures, and left ventricular coronary flows were obtained preoperatively and from 1 to 10 months postoperatively. The majority of the animals developed clinical, laboratory, and pathological evidence of congestive heart failure. All animals had generalized myocardial hypertrophy

Life cycle assessment applied to recycled aggregate concrete

The role of the concrete industry in the growth of modern society and economy is indisputable, as is its contribution to the degradation of the environment. The construction sector has great relevance in the growth of the European economic and social activities. Despite the effects of the 200708 economic crisis, the construction sector contributes to around 9% of the gross domestic product and provides 18 million direct jobs in around three million enterprises in the European Union (EBC, 2017). However, the construction industry is not an environmentally friendly activity. Indeed, it is a major contributor in the degradation of the environment (Bossink and Brouwers, 1996). Negative impacts that have been cited include: land depletion and deterioration, energy consumption, solid waste generation, dust and gas emission, noise pollution and consumption of nonrenewable natural resources (Ofori, 1992). The European construction industry exhausts more than 50% of European natural resources (Schultmann et al., 2010), is responsible for 40% of the total European energy consumption (Zabalza Bribia´n et al., 2009) and generates 34% of the waste produced annually (Eurostat, 2018). Since the first alarm in the 1970s, the reconciliation of economic development with the preservation of the environment has become a major global challenge. Ofthe many environmental impacts of development, those caused by the construction industry have triggered considerable public and governmental concerns that have led to research ways to consume less energy and natural resources and generate less waste. Environmental protection has become an issue of global importance. Within the sustainable measures adopted by the construction industry, the construction and demolition waste (CDW) management and its recycling as secondary aggregates for concrete manufacturing has been studied as a possible way to reduce the environmental pressure on natural resources and to decrease waste generation. Despite the New Trends in Eco-efficient and Recycled Concrete. numerous methods for the evaluation of the environmental impacts, a life cycle assessment (LCA) is one of the most widely employed techniques due to its proficiency to calculate the potential effects that a product, process or service has on the environment over the entire period of its life cycle. This chapter focuses on the particularities of the ecological profile of concrete with recycled aggregates from CDW as assessed using LCA