Quantum radiation pressure on a moving mirror at finite temperature

We compute the radiation pressure force on a moving mirror, in the nonrelativistic approximation, assuming the field to be at temperature $T.$ At high temperature, the force has a dissipative component proportional to the mirror velocity, which results from Doppler shift of the reflected thermal photons. In the case of a scalar field, the force has also a dispersive component associated to a mass correction. In the electromagnetic case, the separate contributions to the mass correction from the two polarizations cancel. We also derive explicit results in the low temperature regime, and present numerical results for the general case. As an application, we compute the dissipation and decoherence rates for a mirror in a harmonic potential well.Comment: Figure 3 replaced, changes mainly in Sections IV and V, new appendix introduced. To appear in Physical Review

Molecular Dynamics of Film Formation of Metal Tetrasulfonated Phthalocyanine and Poly Amidoamine Dendrimers

We performed molecular dynamics computer simulations to elucidate the behavior and properties of the metal tetrasulfonated phthalocyanine molecule and the poly(amidoamine) dendrimers in self-assembly depositions, respectively, on poly(allylamine hydrochloride) polymer and on film formed by metal tetrasulfonated phthalocyanine with poly(allylamine hydrochloride). Important physical properties of phthalocyanines were obtained such as the kinetic energy and temperature in situ. By the semiempirical model, we also obtained the UV-Vis absorption spectrum of the film formed by cobalt tetrasulfonated phthalocyanine deposited on poly(allylamine hydrochloride). We performed a study with poly(amidoamine) dendrimers on their deposition time on metal tetrasulfonated phthalocyanine, poly(allylamine hydrochloride) film, and we show the relationship of deposition time with the electrical charge and molecular mass of phthalocyanines. The deposition times of the dendrimers, as a function of their mass, were also elucidated

Inertial forces in the Casimir effect with two moving plates

We combine linear response theory and dimensional regularization in order to derive the dynamical Casimir force in the low frequency regime. We consider two parallel plates moving along the normal direction in $D-$dimensional space. We assume the free-space values for the mass of each plate to be known, and obtain finite, separation-dependent mass corrections resulting from the combined effect of the two plates. The global mass correction is proportional to the static Casimir energy, in agreement with Einstein's law of equivalence between mass and energy for stressed rigid bodies.Comment: 9 pages, 1 figure; title and abstract changed; to appear in Physical Review

Reactivity, performance, color and tenderness of meat from Zebu cattle finished in feedlot.

The objective of this study was to study the animal reactivity and correlate it with performance and meat quality of cattle finished in feedlots. A total of 20 animals of the Tabapuã breed and 20 animals of the Nellore breed were confined for 112 days: 28 days of adaptation and 84 days of data collection. Performance was determined by the average daily weight gain (ADG) and average dry matter intake (DMI) estimated through the use of indicators. On the 1st, 42nd and 84th days of the experiment, two methods were used to measure the animal reactivity: animal reactivity in mobile cage and visual reactivity during handling. The characteristics of meat quality were evaluated by the color, shear force and pH24 after slaughter (pH24). Through the study of correlation, the degree and direction of linear association on animal reactivity, performance and meat quality were established. Regression equations were generated for the parameters evaluated according to the values of animal reactivity. Correlations between mobile cage and visual reactivity were 0.77, 0.56 and 0.45 in the 1st, 2nd and 3rd evaluations, respectively. There was no correlation between animal reactivity and DMI. The correlations between ADG, pH24, and color with animal reactivity were -0.31, 0.40, 0.47 and -0.34, and -0.33 for mobile cage, 0.74, 0.71 and -0.51, for visual reactivity, respectively. The parameters of meat quality varied according to the reactivity. Undesirable values of pH24, animal reactivity and color were found when mobile cage reactivity was higher than 780, 590 and 540, respectively. In general, animals that show greater reactivity tend to have lower daily weight gain and lower meat quality. The reactivity can be used in animal breeding programs, in order to improve performance and meat quality of Zebu cattle finished in feedlot

Criação de abelhas (apicultura).

Elaboradas em linguagem simples e objetiva, as publicações abordam temas relacionados à agropecuária e mostram como otimizar a atividade rural. A criação de animais, técnicas de plantio, práticas de controle de pragas e doenças, adubação alternativa e fabricação de conservas de frutas são alguns dos assuntos tratados.bitstream/item/11943/2/00081610.pdfProjeto Minibibliotecas

Relationship between feed efficiency indexes and performance, body measurements, digestibility, energy partitioning, and nitrogen partitioning in pre-weaning dairy heifers.

Abstract The objectives of this study were: 1) to classify animals into groups of high and low feed efficiency using two feed efficiency indexes (Residual feed intake (RFI) and residual feed intake and body weight gain (RIG)), and 2) to evaluate if pre-weaning heifer calves divergent for feed efficiency indexes exhibit differences in performance, body measurements, digestibility, energy partitioning, and nitrogen partitioning. A total of 32 Gyr heifer calves were enrolled in a 63-d trial and classified into two feed efficiency (FE) groups based on RFI and RIG (mean ± 0.5 SD). The groups were classified as high efficiency (HE) RFI (HE RFI, n = 9; HE RIG, n = 10), and low efficiency (LE) RFI (LE RFI, n = 10; LE RIG, n = 11). The remaining animals were classified as intermediate (n = 13 (RFI) and n = 11 (RIG)). HE and LE calves had RFI values of?0.052 and 0.049 kg/d (P < 0.05), respectively. The HE RFI group consumed 8.9% less solid diet than the LE RFI group. HE RFI animals exhibited an increased digestibility of crude protein and ether extract and tended to have greater total dry and organic matter digestibility. LE RFI animals had greater gross energy and nitrogen intake, though greater fecal losses resulted in a tendency to reduce energy and nitrogen use efficiency. HE and LE calves had RIG values of 0.080 and -0.077kg/d (P ? 0.01), respectively. HE RIG animals exhibited greater average daily gain (9.4%), body weight (BW), and heart girth, though HE RIG group exhibited narrower hip width. HE RIG animals tended to have greater ether extract digestibility but greater methane losses (% of gross energy). HE RFI in pre-weaning heifers seems to be related to differences in digestibility. Divergent animals for RIG during the assessed phase appear to differ in body measurements, which may be related to differences in the composition of the gain

Search for low-mass WIMPs in a 0.6 kg day exposure of the DAMIC experiment at SNOLAB

We present results of a dark matter search performed with a 0.6 kg day exposure of the DAMIC experiment at the SNOLAB underground laboratory. We measure the energy spectrum of ionization events in the bulk silicon of charge-coupled devices down to a signal of 60 eV electron equivalent. The data are consistent with radiogenic backgrounds, and constraints on the spin-independent WIMP-nucleon elastic-scattering cross section are accordingly placed. A region of parameter space relevant to the potential signal from the CDMS-II Si experiment is excluded using the same target for the first time. This result obtained with a limited exposure demonstrates the potential to explore the low-mass WIMP region (<10 GeV/$c^{2}$) of the upcoming DAMIC100, a 100 g detector currently being installed in SNOLAB.Comment: 11 pages, 11 figure