Franck-Condon Effect in Central Spin System

We study the quantum transitions of a central spin surrounded by a collective-spin environment. It is found that the influence of the environmental spins on the absorption spectrum of the central spin can be explained with the analog of the Franck-Condon (FC) effect in conventional electron-phonon interaction system. Here, the collective spins of the environment behave as the vibrational mode, which makes the electron to be transitioned mainly with the so-called "vertical transitions" in the conventional FC effect. The "vertical transition" for the central spin in the spin environment manifests as, the certain collective spin states of the environment is favored, which corresponds to the minimal change in the average of the total spin angular momentum.Comment: 8 pages, 8 figure

Desempenho de cultivares de mandioca nos Estados da Bahia e de Sergipe entre os anos de 2011 e 2014.

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Extensional flows of polymer solutions in microfluidic converging/diverging geometries

The effects of fluid elasticity in the flow of non-Newtonian fluids in microfluidic converging/diverging geometries are investigated. We investigate the structure and dynamics of inertio-elastic flow instabilities and elastic corner vortices which develop upstream of the contraction plane, and explore their dependence on the relative magnitudes of inertia and elastic stress generated by the high deformation rates in the contraction geometry. The results show that the shape, size and evolution of these flow structures varies with the elasticity number, which is independent of the flow kinematics and is only dependent on fluid properties (viscosity, density and polymer relaxation time) and the characteristic size of the channel

Effect of FMD vaccination schedule of dams on the level and duration of maternally derived antibodies

Vaccination against Foot and Mouth Disease (FMD) in pregnant cows is crucial to produce greater immunity in new born calves, especially in late gestation, as this directly affects neonatal immunity. Therefore, we aimed to investigate how late gestation FMD vaccination of pregnant cows affects the maternally derived antibodies in their offspring. Pregnant cows were vaccinated with and without booster vaccination during the 3rd months (early gestation vaccination, EGV) or the 6.5th months (late gestation vaccination, LGV). Their offspring were investigated for passive immunity transfer, maternal antibody duration, and the first vaccination age of calves (when the maternal antibody has waned sufficiently to allow the first vaccination). Antibody titers were analyzed by a virus neutralization test (VNT). A digital Brix refractometer (% Brix) was used to estimate passive antibody transfer efficiency measuring total protein (TP) content of calf blood sera and also colostrum IgG content. Two linear mixed effects models were fitted: one for the antibody titer values of the dams, and the other for the antibody titer values of calves before the vaccination. A marginal fixed effects model was also fitted to explore the effects of the dam titers on the antibody titers of the calves after their vaccinations. As a result, the average neutralizing antibody titers did not differ between the EGV and LGV groups nor were any differences detected between dams that received a booster and those that were not boosted. However, the LGV calves' mean maternally derived antibody titers were significantly higher (p-values = 0.0001 for both groups) and the duration was longer than that of the EGV calves (120 days in LGV, 60 days in EGV, p 8.4% in both calf groups (9.3 +/- 0.33 in LGV and 8.6 +/- 0.40 in EGV, p > 0.05) indicating that passive immunity transfer had occurred for both groups. In addition, we found that the % Brix mean colostrum IgG content of the LGV (25.8 +/- 1.30) was higher than the EGV (21.8 +/- 0.58) dams (p < 0.01) and a significant positive correlation found between the colostrum density of LGV dams and TP (% Brix) value of their offspring (r = 0.73, p < 0.01). Our results show that vaccination during the late gestation period increased the colostrum IgG content of dams of LGV in addition to the maternally derived antibody duration and potentially provided greater protection of the offspring