Farm Income Stabilization: A Central Goal for American and European Policies

The central thesis developed in this paper is that snapshot views of the global measures of agricultural support mask what is really happening in U.S. and E.U. agricultural policies. We demonstrate that American and European farmers are effectively protected from market risk by these policies. The level of PSE is largely determined by the level of world price. Most economists do not pay much attention to the role of agricultural policies in income stability. Yet farm income stability is clearly a prime objective of government policy both in the E.U. and the U.S. and probably elsewhere. We need to turn out attention to this objective if we are to produce policy analysis relevant to real world policy decisions.agricultural policy, market risks, agricultural income, U.S., E.U., agricultural and natural resource economics, Agricultural and Food Policy,

Information geometry in a reduced model of self-organised shear flows without the uniform coloured noise approximation

We investigate information geometry in a toy model of self-organised shear flows, where a bimodal PDF of x with two peaks signifying the formation of mean shear gradients is induced by a finite memory time γ⁻¹ of a stochastic forcing f . We calculate time-dependent probability density functions (PDFs) for different values of the correlation time γ⁻¹ and amplitude D of the stochastic forcing, and identify the parameter space for unimodal and bimodal stationary PDFs. By comparing results with those obtained under the uniform coloured noise approximation (UCNA) in Jacquet et al (2018 Entropy 20 613), we find that UCNA tends to favor the formation of a bimodal PDF of x for given parameter values γ⁻¹ and D. We map out attractor structure associated with unimodal and bimodal PDFs of x by measuring the total information length L∞ = L(t → ∞) against the location x₀ of a narrow initial PDF of x. Here L(t) represents the total number of statistically different states that a system passes through in time. We examine the validity of the UCNA from the perspective of information change and show how to fine-tune an initial joint PDF of x and f  to achieve a better agreement with UCNA results

Picoheterotroph (Bacteria and Archaea) biomass distribution in the global ocean

We compiled a database of 39 766 data points consisting of flow cytometric and microscopical measurements of picoheterotroph abundance, including both Bacteria and Archaea. After gridding with 1° spacing, the database covers 1.3% of the ocean surface. There are data covering all ocean basins and depths except the Southern Hemisphere below 350m or from April until June. The average picoheterotroph biomass is 3.9 ± 3.6 µg Cl-1 with a 20-fold decrease between the surface and the deep sea. We estimate a total ocean inventory of about 1.3 × 1029 picoheterotroph cells. Surprisingly, the abundance in the coastal regions is the same as at the same depths in the open ocean. Using an average of published open ocean measurements for the conversion from abundance to carbon biomass of 9.1 fg cell-1, we calculate a picoheterotroph carbon inventory of about 1.2 Pg C. The main source of uncertainty in this inventory is the conversion factor from abundance to biomass. Picoheterotroph biomass is ? 2 times higher in the tropics than in the polar oceans

Spin-polarized tunneling spectroscopy in tunnel junctions with half-metallic electrodes

We have studied the magnetoresistance (TMR) of tunnel junctions with electrodes of La2/3Sr1/3MnO3 and we show how the variation of the conductance and TMR with the bias voltage can be exploited to obtain a precise information on the spin and energy dependence of the density of states. Our analysis leads to a quantitative description of the band structure of La2/3Sr1/3MnO3 and allows the determination of the gap delta between the Fermi level and the bottom of the t2g minority spin band, in good agreement with data from spin-polarized inverse photoemission experiments. This shows the potential of magnetic tunnel junctions with half-metallic electrodes for spin-resolved spectroscopic studies.Comment: To appear in Physical Review Letter

Optics Measurements and Matching of TT2-TT10 Line for Injection of the LHC Beam in the SPS

A well matched injection in the SPS is very important for preserving the emittance of the LHC beam. The paper presents the algorithms used for the analysis and the results of the optics measurements done in the transfer line TT2-TT10 and in the SPS. The dispersion is computed by varying the beam momentum and recording the offsets at the BPMs, while the Twiss parameters and emittance measurements in TT2-TT10 are performed with beam profile monitors equipped with OTR screens. These results are completed by those obtained with a matching monitor installed in the SPS as a prototype for the LHC. This device makes use of an OTR screen and a fast acquisition system, to get the turn by turn beam profiles right at injection in the ring, from which the beam mismatch is computed and compared with the results obtained in the line. Finally, on the basis of such measurements, a betatron and dispersion matching of TT2-TT10 for injection in the SPS has been performed and successfully put in operation