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The Paris Agreement introduces long-term strategies as an instrument to inform progressively more ambitious emission reduction objectives, while holding development goals paramount in the context of national circumstances. In the lead up to the twenty-first Conference of the Parties, the Deep Decarbonization Pathways Project developed mid-century low-emission pathways for 16 countries, based on an innovative pathway design framework. In this Perspective, we describe this framework and show how it can support the development of sectorally and technologically detailed, policy-relevant and country-driven strategies consistent with the Paris Agreement climate goal. We also discuss how this framework can be used to engage stakeholder input and buy-in; design implementation policy packages; reveal necessary technological, financial and institutional enabling conditions; and support global stocktaking and increasing of ambition.The Deep Decarbonization Pathways Project develops a framework to design low-emission development pathways. This Perspective discusses the framework and how it can support the development of national strategies to meet climate targets, as well as help achieve stakeholder engagement.

The main objective of the project is to quantify, in the Italian context, some relationships among technology, energy and the economy, which can be used in an existing modeling framework to simulate the impact of atmospheric pollution control policies on the economic system. The framework consists of an Input-Output model with variable coefficients (the PFE model), and a Linear Programming model (MARKAL-Italy), linked by a two-way feedback. The specific object of this project is to expand the energy section of the I/O model to include inter-energy substitution elasticities. For this purpose, econometric models of translog input-demand equations are estimated for thirteen final energy consumption sectors and five energy commodity groups. As a necessary step, a data-base on energy consumption and prices for the various sectors covering the period 1966-1992 is created. A trend decomposition analysis, separating energy consumption in a growth component, an activity mix component and a technological change component, is performed on these data to obtain some insight on the evolution of final energy use. A better understanding of these processes is obtained through a review of energy and environmental policies in Italy over the period considered. Both the quantitative and the descriptive analyses stress the role of fiscal policy on energy products, carried out by the Italian governments, in shaping energy consumption patterns. The effect of including the estimated elasticities in the existing modeling framework is then tested in an experiment in which the technological and economic response of the energy system to changes in CO2 emissions standards is simulated via the LP model MARKAL, and the resulting changes in energy prices are used as inputs into the expanded I/O model. The latter, in turn, measures the impacts of each environmental tax policy scenario on total output, value added, final demand, imports, exports and prices. The results of this experiment, which assumes an explicit tax redistribution scheme, help define the feasibility margin for policy action on CO2 emission standards in the Italian context, indicating the structural changes that would take place as control policies tighten.

Sulphuric acid obtained as a byproduct of non-ferrous metal ore smelting is often the mandatory result of stringent environmental policies adopted in the industrialized countries to limit sulphur dioxide emissions. For the primary copper industry in the southwestern U.S., improvement of sulphuric acid marketing and distribution economies is a critical factor. In this thesis, through a comparison of the European and U.S. sulphuric acid market structure and organization, both the opportunity and the implications of adopting European acid marketing practices are discussed. A more centralized system of acid distribution, as in the European model, if applied to the U.S. smelter acid market, proves to be potentially beneficial for net revenue enhancement. A rationalization of the logistic aspects could substantially reduce acid transportation costs, allow repayment of at least average variable costs of production and improve southwestern smelter acid competitiveness in the domestic markets.

In healthy conditions, the endothelium plays a pivotal role in maintaining vascular homeostasis, mainly by the production of the relaxing factor nitric oxide (NO), which protects the vessel wall from those mechanisms favouring the development of vascular atherosclerosis. Aging is a powerful cardiovascular risk factors associated with endothelial dysfunction. In details, an alteration in the NO substrate l -arginine is the major factor responsible for endothelial dysfunction with advancing age, while reactive oxygen species (ROS) excess generation, which in turn reduce NO availability, plays a role in oldest individuals only. NO inhibition by ROS excess is the main cause of endothelial dysfunction which occurs in many other clinical conditions including arterial hypertension. Although hypertension induces early vascular aging in several arterial districts, however vascular features of physiological aging and hypertension are not necessarily similar. While an impaired NO availability represents the common final effect, aging and hypertension seem to adopt different mechanisms, at least at the level of microcirculation. Indeed, physiological aging shows a progressive reduced NO availability, while in advanced age some degree of oxidative stress emerges. In hypertensive patients, NO availability is early reduced, but the progression rate with age appears to be similar. Whether the hypertensive- and age-related vascular alterations represent only a mere additive effect of two independent risk factors resulting in endothelial dysfunction awaits further clarification.

Central blood pressure is dependent on the stiffness of large arteries and pulse wave reflection. These parameters are very important in the development of hypertensive target organ disease. Moreover, recent clinical studies have shown their independent predictive value for cardiovascular morbidity and mortality. Therefore, 2007 guidelines for the management of hypertension inserted the evaluation of central arterial stiffness as an important component for assessing total cardiovascular risk. Differences in the way various antihypertensive drugs affect arterial stiffness and central hemodynamics may explain the greater cardiovascular protection provided by newer drugs (eg, renin-angiotensin system blockers or calcium channel blockers) independent of peripheral blood pressure reduction, as shown by recent clinical studies. However, the predictive value of the attenuation of arterial stiffness, wave reflections, and central blood pressure still needs to be confirmed in prospective, long-term, large-scale therapeutic trials. Thus, whether these measurements should be routinely performed as a diagnostic or therapeutic indicator remains debatable.