41,571 research outputs found
Chronicle of a Pandemic Foretold. CEPS Policy Insights No 2020-05 / March 2020
In just a few weeks, COVID-19 appeared in China and quickly spread to the rest of the world,
including Europe and the United States. Many have rushed to describe the outbreak as a âblack
swanâ â an unpredictable event with extremely severe consequences. However, COVID-19 was not
only predictable ex post: it was amply predicted ex ante. This allows us to draw some preliminary
lessons:
âą First, economic policy will need to shift from its current focus on efficiency, towards a greater
emphasis on resilience and sustainability.
âą Second, a more centralised governance to address health emergencies is needed.
âą Third, Europe should create a centre for the prevention of large-scale risks.
âą Fourth, digital technologies, if handled with care, can be an important part of both a mitigation
and a response strategy.
âą Fifth, Europe should improve its science advice and communication functions.
Finally, there are many ways to pursue enhanced resilience and responsiveness, but not all of them
are compatible with sustainability and democratic values. The challenge is to find an adequate
policy mix, which safeguards individual rights and liberties, protects the economy, and at the same
time strengthens government preparedness for cases of epidemics and pandemics
Phosphorus retention capacity in red ferralitic soil
In this study the main physical-chemical characteristics of red ferralitic soil to use as substrate in subsurface wetlands was determined. The P-removal was evaluated in a short-term isotherm batch experiment and in a column percolation experiment. The acid characteristic and high content of iron minerals in the red ferralitic soil facilitated the phosphorus removal. Also the sorption isotherms at two different temperatures were obtained. The results showed that the sorption capacity increases with an increase in solution temperature from 25 to 35 degrees C. The experimental data were fitted to Langmuir and Freundlich models, having a better fit to the Freundlich isotherms. The maximum P-sorption capacities estimated using the Langmuir isotherm were 0.96 and 1.13 g/kg at 25 and 35 degrees C respectively. Moreover a column experiment was carried out at two different flows. Sequential extractions of the phosphorus-saturated soil indicated that phosphorus is mainly bound with iron or aluminum minerals. The results have demonstrated a good potential for red ferralitic soil for phosphorus removal from urban wastewater
Estimation of Nonparametric Functions in Simultaneous Equations Models, with an Application to Consumer Demand
We present a method for consistently estimating nonparametric functions and distributions in simultaneous equations models. This method is used to identify and estimate a random utility model of consumer demand. Our identification conditions for this particular model extend the results of Houthakker (1950), Uzawa (1971) and Mas-Colell (1977), where a deterministic utility function is uniquely recovered from its deterministic demand function.
Axial and Vector Correlator Mixing in Hot and Dense Hadronic Matter
We study the manifestations of chiral symmetry restoration which have a
significance for the parity mixing. Restricting to pions and nucleons we
establish a formalism for the expression of the vector correlator, which
displays the mixing of the axial correlator into the vector one and unifies the
cases of the heat bath and the dense medium. We give examples of mixing
cross-sections. We also establish a link between the energy integrated mixing
cross-sections and the pion scalar density which governs the quenching factors
of coupling constants, such as the pion decay one, as well as the quark
condensate evolution.Comment: 12 pages, Latex, 4 PostScript Figure
Bounds on Cubic Lorentz-Violating Terms in the Fermionic Dispersion Relation
We study the recently proposed Lorentz-violating dispersion relation for
fermions and show that it leads to two distinct cubic operators in the
momentum. We compute the leading order terms that modify the non-relativistic
equations of motion and use experimental results for the hyperfine transition
in the ground state of the ion to bound the values of the
Lorentz-violating parameters and for neutrons. The resulting
bounds depend on the value of the Lorenz-violating background four-vector in
the laboratory frame.Comment: Revtex 4, four pages. Version to match the one to appear in Physical
Review
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