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We define and model research production at Embrapa, the major Brazilian institution responsible for applied agricultural research. The main theoretical framework we use is Data Envelopment Analysis – DEA. We explore the economic interpretation of these models to assess scale, congestion and cost efficiencies. We use efficiency results to test for(More)
The generation of dc magnetic fields in unmagnetized electron-ion shear flows is shown to be associated to either initial thermal effects or the onset of electron-scale shear instabilities, in particular the cold Kelvin-Helmholtz instability. This mechanism, intrinsic to shear gradients on the electron scale, is described through a kinetic model that(More)
Ensuring food security for the worlds population over the coming decades will face the challenges of a larger world population, greater urbanization, limited natural resources, higher levels of income, and stronger links between the agricultural and biofuel markets. Overcoming the challenges these represent will require, among other efforts, promoting(More)
Electron-scale surface waves are shown to be unstable in the transverse plane of a sheared flow in an initially unmagnetized collisionless plasma, not captured by (magneto)hydrodynamics. It is found that these unstable modes have a higher growth rate than the closely related electron-scale Kelvin-Helmholtz instability in relativistic shears.(More)
We study the conductance statistical features of ballistic electrons flowing through a chaotic quantum dot. We show how the temperature affects the universal conductance fluctuations by analyzing the influence of dephasing and thermal smearing. This leads us to two main findings. First, we show that the energy correlations in the transmission, which were(More)
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