Modelling Health Impacts of Air Pollution and Their Valuation: An Application to Santiago, Chile

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TEMPERED RELAXATION EQUATION AND RELATED GENERALIZED STABLE PROCESSES

Fractional relaxation equations, as well as relaxation functions time-changed by independent stochastic processes have been widely studied (see, for example, MAI, STAW and GAR). We start here by proving that the upper-incomplete Gamma function satisfies the tempered-relaxation equation (of index ρ∈(0,1)); thanks to this explicit form of the solution, we can then derive its spectral distribution, which extends the stable law. Accordingly, we define a new class of selfsimilar processes (by means of the n-times Laplace transform of its density) which is indexed by the parameter ρ: in the special case where ρ=1, it reduces to the stable subordinator. Therefore the parameter ρ can be seen as a measure of the local deviation from the temporal dependence structure displayed in the standard stable case

Robust estimates of value of a statistical life for developing economies

Environmental economists use the value-of-statistical-life (VSL) approach to value mortality changes resulting from environmental improvement. Because of scarce data, VSL estimates are unavailable for most developing countries. Using robust regression techniques, we conduct a meta-analysis of VSL studies in industrialized countries to derive a VSL prediction function for developing economies accounting for differences in risk, income, human capital levels, and other demographic characteristics of these economies. We apply our estimated VSL to assess the willingness to pay for reduction in mortality linked to air pollution in Santiago, Chile. We find willingness-to-pay estimates in the range of 1992 purchasing power parity (PPP) $519,000–675,000 per life

Conditional maximal distributions of processes related to higher-order heat-type equations

The conditional Feynman-Kac functional is used to derive the Laplace transforms of conditional maximum distributions of processes related to third- and fourth-order equations. These distributions are then obtained explicitly and are expressed in terms of stable laws and the fundamental solutions of these higher-order equations. Interestingly, it is shown that in the third-order case, a genuine non-negative real-valued probability distribution is obtained. (C) 2000 Elsevier Science B.V. All rights reserved

Impact of the Berlin Accord and European Enlargement on Dairy Markets, The

Using a world agricultural model, we analyze the impact on dairy markets of the Berlin Accord on the European Union (EU) Common Agricultural Policy (CAP) Reforms. We also investigate the consequences of enlargement of the EU to include the Czech Republic, Hungary and Poland for the same markets. We produce a market outlook up to 2010 for these two scenarios. The Berlin Accord induces lower EU milk and dairy prices. A change in relative prices between cheese and butter-skim milk powder (SMP) occurs after 2005 and induces an expansion of cheese production, consumption and exports at the expense of the butterï¾–SMP sector. Accession of the three central and eastern European countries (CEECs) leads to a permanent but moderate decrease in EU prices of milk and dairy products. For the three acceding CEECs, domestic prices increase dramatically. Their final consumption of milk decreases and dairy product consumption drops considerably. The derived demand of milk in dairy production increases, however, because of the higher prices for dairy products, benefiting dairy producers in these CEECs. Dairy exports of the three acceding countries to the EUï¾–15 increase by one to three orders of magnitude, despite building large inventories. The impact of accession on world markets is small.

The impact of COVID-19 and associated policy responses on global food security

We analyze the impact of the COVID-19 pandemic and associated policy responses on the global economy and food security in 80 low- and middle-income countries. We use a global economy-wide model with detailed disaggregation of agricultural and food sectors and develop a business-as-usual baseline for 2020 and 2021 called “But-for-COVID” (BfC). We then shock the model with aggregate income shocks derived from the IMF World Economic Outlook for 2020 and 2021. We impose total-factor productivity losses in key sectors as well as consumption decreases induced by social distancing. The resulting shocks in prices and incomes from the CGE model simulations are fed into the USDAERS International Food Security Assessment (IFSA) model to derive the impact of the pandemic on food security in these 80 countries. The main effect of the pandemic was to exacerbate the existing declining trend in food security. Food insecurity increases considerably in countries in Asia through income shocks rather than prices effects.We also review trade policies that were put in place to restrict imports and exports of food, and we evaluate their potential for further disruption of markets focusing on the food-security implications

The Impact of The European Enlargement and CAP Reforms on Agricultural Markets. Much Ado about Nothing?

We analyze the effects of the 2004 CAP reform and EU enlargement on European and world agricultural markets. We compare the results from a CAP reform only and a CAP reform plus enlargement scenarios to a no-enlargement baseline implementing Agenda 2000 CAP policies. We utilize the Food and Agricultural Policy Research Institute's policy analysis model to simulate the effects of CAP reform and EU enlargement on production, consumption, and trade for the EU, its New Member States (NMS), and major players in world agricultural markets. The model is a partial-equilibrium model of world agricultural markets including important producer and consumer countries in world livestock and products, dairy, grains, oilseeds and products, cotton and sugar markets. Each country's commodity sectors are modeled with structural equations which incorporate all important policy parameters. With prices in most commodities in the NMS historically below EU-15 prices accession leads to substantial price increases for many commodities in the NMS. Higher prices stimulate production and dampen consumption in the NMS, and trade between the new members and the EU-15 increases. Prices in the EU-15 decrease moderately. The impact of the two reforms on world markets is negligible. The CAP reforms have their greatest impact in the EU-15 markets for meats, rice, rapeseed, and dairy products. CAP reforms without enlargement generate a small increase in world and EU commodity prices.CAP, trade reform, policy reform, enlargement, new member states, European Union, Agricultural and Food Policy, Marketing, F1, Q17, Q18,

Microfossils from the late Mesoproterozoic - early Neoproterozoic Atar/EI Mreiti Group, Taoudeni Basin, Mauritania, northwestern Africa

The well-preserved Meso-Neoproterozoic shallow marine succession of the Atar/EI Mreiti Group, in the Taoudeni Basin, Mauritania, offers a unique opportunity to investigate the mid-Proterozoic eukaryotic record in Western Africa. Previous investigations focused on stromatolites, biomarkers, chemostratigraphy and palaeoredox conditions. However, only a very modest diversity of organic-walled microfossils (acritarchs) has been documented. Here, we present a new, exquisitely well-preserved and morphologically diverse assemblage of organic-walled microfossils from three cores drilled through the Atar/El Mreiti Group. A total of 48 distinct entities including 11 unambiguous eukaryotes (ornamented and process-bearing acritarchs), and 37 taxonomically unresolved taxa (including 9 possible eukaryotes, 6 probable prokaryotes, and 22 other prokaryotic or eukaryotic taxa) were observed. Black shales preserve locally abundant fragments of organic-rich laminae interpreted as benthic microbial mats. We also document one of the oldest records of Leiosphaeridia kulgunica, a species showing a circular opening interpreted as a sophisticated circular excystment structure (a pylome), and one of the oldest records of Trachyhystrichosphaera aimika and T. botula, two distinctive process-bearing acritarchs present in well dated 1.1 Ga formations at the base of the succession. The general assemblage composition and the presence of three possible index fossils (A. tetragonala, S. segmentata and T. aimika) support a late Mesoproterozoic to early Neoproterozoic (Tonian) age for the Atar/El Mreiti Group, consistent with published lithostratigraphy, chemostratigraphy and geochronology. This study provides the first evidence for a moderately diverse eukaryotic life, at least 1.1 billion years ago in Western Africa. Comparison with coeval worldwide assemblages indicates that a broadly similar microbial biosphere inhabited (generally redox-stratified) oceans, placing better time constraints on early eukaryote palaeogeography and biostratigraphy