Signatures of quantum phase transitions in parallel quantum dots: Crossover from local-moment to underscreened spin-1 Kondo physics

We study a strongly interacting "quantum dot 1" and a weakly interacting "dot 2" connected in parallel to metallic leads. Gate voltages can drive the system between Kondo-quenched and non-Kondo free-moment phases separated by Kosterlitz-Thouless quantum phase transitions. Away from the immediate vicinity of the quantum phase transitions, the physical properties retain signatures of first-order transitions found previously to arise when dot 2 is strictly noninteracting. As interactions in dot 2 become stronger relative to the dot-lead coupling, the free moment in the non-Kondo phase evolves smoothly from an isolated spin-one-half in dot 1 to a many-body doublet arising from the incomplete Kondo compensation by the leads of a combined dot spin-one. These limits, which feature very different spin correlations between dot and lead electrons, can be distinguished by weak-bias conductance measurements performed at finite temperatures.Comment: 7 pages, 7 figures. Accepted for publication in Phys. Rev.

Qualidade fisiológica da semente e estabelecimento de plantas de hortaliças no campo.

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Comparison of the C-mediating killing activity and C-activating properties of mouse monoclonal and polyclonal antibodies against Trypanosoma cruzi

A Mouse polyclonal antiserum against Trypanosoma cruzi or its IgG and IgM fractions and five monoclonal antibodies (two IgM, two IgG1 and one IgG2a) recognize and combine with membrane components of trypomastigote forms of the parasite as revealed by immunofluorescence. Although all these antibodies sensitize trypomastigotes and prepare them to activate the complement (C) system, as measured by consumption of total C, C4, B and C3, only the polyclonal antiserum or its IgG, IgM and Fabμ fragments were able to induce trypanosome lysis by the alternative C pathway

Exchange interaction effects in the thermodynamic properties of quantum dots

We study electron-electron interaction effects in the thermodynamic properties of quantum-dot systems. We obtain the direct and exchange contributions to the specific heat C_v in the self-consistent Hartree-Fock approximation at finite temperatures. An exchange-induced phase transition is observed and the transition temperature is shown to be inversely proportional to the size of the system. The exchange contribution to C_v dominates over the direct and kinetic contributions in the intermediate regime of interaction strength (r_s ~ 1). Furthermore, the electron-electron interaction modifies both the amplitude and the period of magnetic field induced oscillations in C_v.Comment: 4 pages, 4 figures; To appear in Phys. Rev.

Production and economic viability of Kent mango subjected to regulated deficit irrigation in the semi-arid.

Mango (Mangifera indica L.) production has great importance for Brazilian agriculture, being concentrated in the states of Bahia and Pernambuco. Although mango is a drought-tolerant crop, inadequate irrigation management reduces its yield. Thus, the objective was to evaluate production parameters and economic viability of ‘Kent’ mango subjected to controlled water deficit in the phenological stages of flowering, fruit growth and maturation. The experiment was conducted in the municipality of Petrolina/PE, semi-arid region of the São Francisco Valley, in a ultisol. The experimental design was randomized blocks, in a triple factorial scheme, with application of four irrigation depths (40, 60, 80 and 100% of crop evapotranspiration -ETc), three phenological stages (F1 -flowering, F2 -fruit growth, F3 -fruit maturation) and two production cycles (2018 and 2019 seasons), with four replicates, each of which consisting of four plants. The irrigation with 40% ETc in the flowering stage and 80% of the ETc in the growing and ripening of fruits phases promoted higher yield, water use efficiency and benefit/cost ratio in the cultivation of ‘Kent’ mango in the Brazilian semi-arid region