On the Estimation of Euler Equations in the Presence of a Potential Regime Shift

The concept of a peso problem is formalized in terms of a linear Euler equation and a nonlinear marginal model describing the dynamics of the exogenous driving process. It is shown that, using a threshold autoregressive model as a marginal model, it is possible to produce time-varying peso premia. A Monte Carlo method and a method based on the numerical solution of integral equations are considered as tools for computing conditional future expectations in the marginal model. A Monte Carlo study illustrates the poor performance of the generalized method of moment (GMM) estimator in small and even relatively large samples. The poor performance is particularly acute in the presence of a peso problem but is also serious in the simple linear case.peso problem; Euler equations; GMM; threshold autoregressive models

Response to Comment on `Undamped electrostatic plasma waves' [Phys. Plasmas 19, 092103 (2012)]

Numerical and experimental evidence is given for the occurrence of the plateau states and concomitant corner modes proposed in \cite{valentini12}. It is argued that these states provide a better description of reality for small amplitude off-dispersion disturbances than the conventional Bernstein-Greene-Kruskal or cnoidal states such as those proposed in \cite{comment

Radial evolution of the solar wind in pure high-speed streams: HELIOS revised observations

Spacecraft observations have shown that the proton temperature in the solar wind falls off with radial distance more slowly than expected for an adiabatic prediction. Usually, previous studies have been focused on the evolution of the solar-wind plasma by using the bulk speed as an order parameter to discriminate different regimes. In contrast, here, we study the radial evolution of pure and homogeneous fast streams (i.e. well-defined streams of coronal-hole plasma that maintain their identity during several solar rotations) by means of re-processed particle data, from the HELIOS satellites between 0.3 and 1 au. We have identified 16 intervals of unperturbed high-speed coronal-hole plasma, from three different sources and measured at different radial distances. The observations show that, for all three streams, (i) the proton density decreases as expected for a radially expanding plasma, unlike previous analysis that found a slower decrease; (ii) the magnetic field deviates from the Parker prediction, with the radial component decreasing more slowly and the tangential more quickly than expected; (iii) the double-adiabatic invariants are violated and an increase of entropy is observed; (iv) the collisional frequency is not constant, but decreases as the plasma travels away from the Sun. This work provides an insight into the heating problem in pure fast solar wind, fitting in the context of the next solar missions, and, especially for Parker Solar Probe, it enables us to predict the high-speed solar-wind environment much closer to the Sun

investigation of integrated organic rankine cycles and wind turbines for micro scale applications

Abstract The aim of this work is the investigation of the performance of an innovative biomass/wind energy integrated system for Combined Heat and Power (CHP) generation in small-scale applications. The system is based on an Organic Rankine Cycle (ORC) fed with biomass and a wind turbine (WT). The ORC and WT sub-systems operate in parallel to produce the required electrical energy and an auxiliary boiler provides thermal energy if the CHP output is low. A preliminary investigation is performed to define the proper size of the wind turbine. Afterwards, the analysis is focused on the integrated system. In particular, the application to the Italian residential sector is analysed. Results illustrate that hybridisation improves the global conversion efficiency, by reducing the biomass consumption and overcoming the intermittency of the wind source. When the wind source is significant, the ORC system can be switched off or operated at partial load

Alpha particle thermodynamics in the inner heliosphere fast solar wind

Context. Plasma processes occurring in the corona and solar wind can be probed by studying the thermodynamic properties of different ion species. However, most in-situ observations of positive ions in the solar wind are taken at 1 AU, where information on their solar source properties may have been irreversibly erased. Aims. In this study we aimed to use the properties of alpha particles at heliocentric distances between 0.3 and 1 AU to study plasma processes occurring at the points of observation, and to infer processes occurring inside 0.3 AU by comparing our results to previous remote sensing observations of the plasma closer to the Sun. Methods. We reprocessed the original Helios positive ion distribution functions, isolated the alpha particle population, and computed the alpha particle number density, velocity, and magnetic field perpendicular and parallel temperatures. We then investigated the radial variation of alpha particle temperatures in fast solar wind observed between 0.3 and 1 AU. Results. Between 0.3 and 1 AU alpha particles are heated in the magnetic field perpendicular direction, and cooled in the magnetic field parallel direction. Alpha particle evolution is bounded by the alpha firehose instability threshold, which provides one possible mechanism to explain the observed parallel cooling and perpendicular heating. Closer to the Sun our observations suggest that the alpha particles undergo heating in the perpendicular direction, whilst the large magnetic field parallel temperatures observed at 0.3 AU may be due to the combined effect of double adiabatic expansion and alpha particle deceleration inside 0.3 AU

Analysis of multi-source energy system for small-scale domestic applications. Integration of biodiesel, solar and wind energy

The paper aims at analysing the energy performance of an innovative multi-source energy system for residential small-scale combined heat and power (CHP) applications. The integrated system is based on an Organic Rankine Cycle (ORC) fuelled by biodiesel, a wind turbine, and a photovoltaic unit. The application refers to the Italian residential sector. The ORC system operates in order to satisfy the thermal demand of domestic users while wind and solar based sub-systems work in parallel to increase the electric self-consumption rate. An auxiliary boiler provides thermal energy when the CHP thermal output is low. Furthermore, when the solar and/or wind sources are significant, the ORC can be switched-off or operated at partial load.A preliminary investigation is performed to define the proper size of the ORC unit. Afterwards, the analysis is focused on a multi-variable optimisation of the integrated system. In particular, the nominal power of the wind turbine and photovoltaic units have been found in order to guarantee a proper trade-off between electric self-consumed and surplus energy. Keywords: Biodiesel, Combined heat and power, Multi-source generation, Organic Rankine cycle, Solar, Win

Molecular complexity of diffuse large B-cell lymphoma: Can it be a roadmap for precision medicine?

Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma; it features extreme molecular heterogeneity regardless of the classical cell-of-origin (COO) classification. Despite this, the standard therapeutic approach is still immunochemotherapy (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone—R-CHOP), which allows a 60% overall survival (OS) rate, but up to 40% of patients experience relapse or refractory (R/R) disease. With the purpose of searching for new clinical parameters and biomarkers helping to make a better DLBCL patient characterization and stratification, in the last years a series of large discovery genomic and transcriptomic studies has been conducted, generating a wealth of information that needs to be put in order. We reviewed these researches, trying ultimately to understand if there are bases offering a roadmap toward personalized and precision medicine also for DLBCL