Magnetic reconfiguration of MnAs/GaAs(001) observed by Magnetic Force Microscopy and Resonant Soft X-ray Scattering

We investigated the thermal evolution of the magnetic properties of MnAs epitaxial films grown on GaAs(001) during the coexistence of hexagonal/orthorhombic phases using polarized resonant (magnetic) soft X-ray scattering and magnetic force microscopy. The results of the diffuse satellite X-ray peaks were compared to those obtained by magnetic force microscopy and suggest a reorientation of ferromagnetic terraces as temperature rises. By measuring hysteresis loops at these peaks we show that this reorientation is common to all ferromagnetic terraces. The reorientation is explained by a simple model based on the shape anisotropy energy. Demagnetizing factors were calculated for different configurations suggested by the magnetic images. We noted that the magnetic moments flip from an in-plane mono-domain orientation at lower temperatures to a three-domain out-of-plane configuration at higher temperatures. The transition was observed when the ferromagnetic stripe width L is equal to 2.9 times the film thickness d. This is in good agreement with the expected theoretical value of L = 2.6d.Comment: 16 pages in PD

Measurement of interaction energy near a Feshbach resonance in a 6Li Fermi gas

We investigate the strongly interacting regime in an optically trapped $^6$Li Fermi mixture near a Feshbach resonance. The resonance is found at $800(40)$G in good agreement with theory. Anisotropic expansion of the gas is interpreted by collisional hydrodynamics. We observe an unexpected and large shift ($80$G) between the resonance peak and both the maximum of atom loss and the change of sign of the interaction energy.Comment: 4 pages, 4 figure

Avaliação de leguminosas arbóreas e arbustivas de mútiplo uso em Rondônia

Selecao de leguminosas arboreas e arbustivas de multiplos propositos (Acacia angustissima, Albizia saman, A. lebbek, Desmodium gynoides, Sesbania sesban, Calliandra calothyrsus, Leucaena leucocephala, L. hybrid x1, L. hybrid x2, L. hybrid x3, Inga edulis, Clitoria racemosa, anandenanthera pavonina, Caesalpina peltephoroides), em parcelas experimentais com 16 plantas sem repeticoes. Foi avaliada taxa de sobrevivencia, diametro e altura aos 6, 12, 18 e 24 meses. A taxa de sobrevivencia foi de 100% aos seis meses de idade. Os maiores DAPs aos seis e doze meses foram para A. angustissima, I. edulis, a. pavonina. Considerando-se os parametros avaliados, as especies mais promissoras, principalmente para compor sistemas agroflorestais, foram: A. angustissima, I. edulis, A. saman e A. pavonina.bitstream/item/84465/1/FOL-5342-0001.pd

Germinação de urediniósporos de Phakopsora euvitis sob diferentes aumentos da temperatura.

Suplemento. Edição dos Resumos do 44 Congresso Brasileiro de Fitopatologia, Bento Gonçalves, ago. 2011

Three-vortex configurations in trapped Bose-Einstein condensates

We report on the creation of three-vortex clusters in a $^{87}Rb$ Bose-Einstein condensate by oscillatory excitation of the condensate. This procedure can create vortices of both circulation, so that we are able to create several types of vortex clusters using the same mechanism. The three-vortex configurations are dominated by two types, namely, an equilateral-triangle arrangement and a linear arrangement. We interpret these most stable configurations respectively as three vortices with the same circulation, and as a vortex-antivortex-vortex cluster. The linear configurations are very likely the first experimental signatures of predicted stationary vortex clusters.Comment: 4 pages, 4 figure

Características subjetivas e sensoriais da carne de cordeiros mestiços terminados em confinamento.

Resumo: A avaliação das características qualitativas da carcaça bem como a análise sensorial, são parâmetros que vem somar no intuito de completar a avaliação do desempenho animal. O presente estudo foi conduzido para avaliar as características subjetivas e sensoriais da carne de cordeiro (½ Santa Inês-SI x ½ SPRD e ½ Somalis Brasileira-SB x ½ SPRD) terminados em confinamento. Foram utilizados dezesseis cordeiros, machos, inteiros com peso corporal médio inicial de 19,7±2,0kg. Os animais foram alojados em baias coletivas (15,25 m2) com piso de chão batido. O delineamento utilizado foi em blocos ao acaso. Utilizou-se o software SAS® 9.1 para as análises estatísticas. As carcaças foram refrigeradas a 4oC por 24 horas e, em seguida foram extraído os Longissimus dorsi para a mensuração das variáveis subjetivas como também para as características sensoriais. Na avaliação subjetiva foi verificado que houve efeito significativo entre os genótipos avaliados para a quantidade de marmoreio e distribuição da gordura de marmoreio, sendo maiores para o genótipo ½ SB x ½ SPRD. O fato da raça Somalis Brasileiro apresentar uma tendência ao acúmulo de gordura na carcaça, pode ter influenciado essas variáveis. Em relação à análise sensorial foi observada diferença apenas para cor. Os diferentes genótipos apresentaram uma carne de boa qualidade e aceitação. No entanto, quando se desejar obter uma carne com maior quantidade de gordura intramuscular, o genótipo ½ SB x ½ SPRD é mais satisfatório. [Subjective and sensory characteristics of meat crossbred lambs finished feedlot]. Abstract: The present study was led to evaluate the subjective and sensory characteristics of the lamb meat (½ Santa Inês-SI x ½ undefined breed and ½ Somalis Brazileira-SB x ½undefined breed) finished in feedlot. Sixteen lambs were used, males, non-castrated with initial body weight of 19,7±2,0kg.The animals were housed in collective cages (15,25 m2) with dirt floor. The experimental design was in randomized blocks with statistical analysis using the program SAS®. Slaughter of the animals occurred mechanically with desensitization of the atlanto-occipital region. Carcasses were refrigerated to 4oC for 24 hours. The Longissimus dorsi were extracted for measurement of subjective variables as well as to the sensory characteristics. In the subjective evaluation it was verified that there was significant effect among the appraised genotype for marbling score and distribution of fat marbling, were higher for genotype ½ Somalis Brazileira x ½undefined breed. The fact of breed Somalis Brazileira to present a tendency to accumulate fat in the carcass, can have influenced those variables. In relation to the sensorial analysis was observed differentiates just for color. The different genotypes presented a meat of good quality. When if want to get a meat with higher quantity of fat marbling, the genotype ½ Somalis Brazileira x ½undefined breed is more suitable