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With the ratification of the Paris climate agreement to avoid the uncompensated effects of climate change, 197 countries will have to dramatically reduce their greenhouse gas emissions in half by 2030. In the case of the urban space, roads are responsible for the consumption of 105M tons of bitumen and 115M tons of the world's greenhouse gas emissions. For this reason, the reduction of the environmental impacts of road construction is becoming an urgent necessity. So far the vast majority of the Life cycle assessment (LCA) has been used to evaluate the environmental burdens of existing roads and new asphalt solutions. However, due to the different LCA methodological choices, recent studies have highlighted the difficulties in comparing the results of cases published in literature. Driven by this knowledge gap, the aim of the present study was to identify key aspects missing in the assessment of urban roads. Through a Systematic Literature Review (SLR), 47 publications have been selected for further investigation. An intensive analysis of these documents clearly demonstrate the heterogeneity of the applied LCA methodological choices as well as the selected approaches regarding i.e. the goal of the studies, functional unit, system boundary, database and stratigraphy of the road pavement. Aiming to harmonize the LCA methodology, we have identified key aspects that require solutions for a robust LCA application. The results are expected to be useful for the National Road Administration (NRA) in assessing the environmental impacts of future urban road projects. As a response to the Paris climate agreement targets, the application of harmonized methods regarding LCA should lead to a more robust and structured process in terms of identifying low carbon urban road solutions and contributing to the SDGs respectively.

Solving the problems of high energy consumption and high emissions generated by the urban road systems is of great importance for the construction of low-carbon cities. Several tools have been developed to establish a method to evaluate the carbon emission related to the life cycle of road pavements. However, the lack of key basic data such as energy consumption, pollutants and carbon emissions, and accurate management policies have hindered the transition of urban roads to clean, low-carbon systems. The HERMES project aims to compile long-term dynamic inventory of urban road energy consumption and environmental emissions and build a life cycle model. The Data Envelopment Analysis model will be used to predict the energy saving and emission reduction potential of urban roads depending on the technological solution, establish a multi-criteria evaluation system that includes energy, environment, and economic parameters, identify the best available technological solution in different cities, and propose a more targeted and effective clean low-carbon management policies. The study will provide an accurate understanding of the environmental impact of urban roads in China and Europe, evaluate the potential for energy saving and emission reduction, and provide theoretical data and decision-making reference for a clean, low-carbon transition.

OBJECTIVE: To determine the role of matrix metalloproteinases (MMPs) in retinoic acid (RetA)-induced degradation of type II collagen in cartilage. METHODS: Bovine nasal cartilage explants were cultured with 1 microM RetA or in 3 nM interleukin-1alpha (IL-1alpha). Release of proteoglycan and type II collagen into the medium was measured by colorimetric assay and immunoassay, respectively. MMP activity in the medium was determined using a quenched fluorescent substrate assay, while specific collagenases were identified by Western immunoblotting. In some cases the effects of low molecular mass synthetic MMP inhibitors and serum on collagen degradation were studied. RESULTS: RetA promoted maximal breakdown of type II collagen after 4 or 5 weeks in culture, compared with 3 weeks in culture with IL-1alpha. In IL-1alpha-stimulated cultures, collagen degradation was coincident with a large increase in MMP activity in the culture medium, whereas in RetA-stimulated cultures, there was only a small increase. In Western immunoblots of culture media containing RetA, prointerstitial collagenase and active collagenase 3 were sometimes detected, but not in all experiments. In IL-1alpha cultures, active interstitial collagenase was always detected, and active collagenase 3 was detectable in some experiments. Neutrophil collagenase was not detected in any cultures. IL-1alpha-stimulated collagen degradation was effectively inhibited by a potent, broad-spectrum inhibitor of MMPs, whereas it was poorly inhibited by a weak MMP inhibitor. The same 2 compounds were both only weak inhibitors of RetA-induced collagen degradation. When fetal calf serum was included in cartilage cultures, MMP activity in the culture medium was reduced to low levels. This resulted in a marked inhibition of IL-1alpha-induced type II collagen degradation, whereas there was no inhibition of RetA-induced collagen degradation. CONCLUSION: Unlike IL-1alpha, RetA induces degradation of type II collagen in cartilage explants by a mechanism that is mainly independent of those MMPs that can be detected in the culture medium.

The IEA EBC Annex 72 focuses on the assessment of the primary energy demand, greenhouse gas emissions and environmental impacts of buildings during production, construction, use (including repair and replacement) and end of life (dismantling), i.e. during the entire life cycle of buildings. In one of its activities, reference buildings (size, materialisation, operational energy demand, etc.) were defined on which the existing national assessment methods are applied using national (if available) databases and (national/regional) approaches. The "be2226" office building in Lustenau, Austria was selected as one of the reference buildings. TU Graz established a BIM model and quantified the amount of building elements as well as construction materials required and the operational energy demand. The building assessment was carried out using the same material and energy demand but applying the LCA approach used in the different countries represented by the participating Annex experts. The results of these assessments are compared in view of identifying major discrepancies. Preliminary findings show that the greenhouse gas emissions per kg of building material differ up to a factor of two and more. Major differences in the building assessments are observed in the transports to the construction site (imports) and the construction activities as well as in the greenhouse gas emissions of the operational energy demand (electricity). The experts document their practical difficulties and how they overcame them. The results of this activity are used to better target harmonisation efforts.

The IEA EBC Annex 72 focuses on the assessment of the primary energy demand, greenhouse gas emissions and environmental impacts of buildings during production, construction, use (including repair and replacement) and end of life (dismantling), i.e. during the entire life cycle of buildings. In one of its activities, reference buildings (size, materialisation, operational energy demand, etc.) were defined on which the existing national assessment methods are applied using national (if available) databases and (national/regional) approaches. The ?be2226? office building in Lustenau, Austria was selected as one of the reference buildings. TU Graz established a BIM model and quantified the amount of building elements as well as construction materials required and the operational energy demand. The building assessment was carried out using the same material and energy demand but applying the LCA approach used in the different countries represented by the participating Annex experts. The results of these assessments are compared in view of identifying major discrepancies. Preliminary findings show that the greenhouse gas emissions per kg of building material differ up to a factor of two and more. Major differences in the building assessments are observed in the transports to the construction site (imports) and the construction activities as well as in the greenhouse gas emissions of the operational energy demand (electricity). The experts document their practical difficulties and how they overcame them. The results of this activity are used to better target harmonisation efforts., IEA -International Association for the Evaluation of Educational Achievement(Slovenia)