A long-range and long-life telemetry data-acquisition system for heart rate and multiple body temperatures from free-ranging animals

The system includes an implantable transmitter, external receiver-retransmitter collar, and a microprocessor-controlled demodulator. The size of the implant is suitable for animals with body weights of a few kilograms or more; further size reduction of the implant is possible. The ECG is sensed by electrodes designed for internal telemetry and to reduce movement artifacts. The R-wave characteristics are then specifically selected to trigger a short radio frequency pulse. Temperatures are sensed at desired locations by thermistors and then, based on a heartbeat counter, transmitted intermittently via pulse interval modulation. This modulation scheme includes first and last calibration intervals for a reference by ratios with the temperature intervals to achieve good accuracy even over long periods. Pulse duration and pulse sequencing are used to discriminate between heart rate and temperature pulses as well as RF interference

Pd/Cu Site Interchange and Non-Fermi-Liquid Behavior in UCu_4Pd

X-ray-absorption fine-structure measurements of the local structure in UCu_4Pd are described which indicate a probable lattice-disorder origin for non-Fermi-liquid behavior in this material. Short Pd-Cu distances are observed, consistent with 24 +/- 3% of the Pd atoms occupying nominally Cu sites. A "Kondo disorder" model, based on the effect on the local Kondo temperature T_K of this interchange and some additional bond-length disorder, agrees quantitatively with previous experimental susceptibility data, and therefore also with specific heat and magnetic resonance experiments.Comment: 4 pages, 3 PostScript figures, to be published in PR

Umbuzeiro (Spondias tuberosa Arruda): planta nativa da caatinga, importante repositório natural de moscas-das-frutas.

O objetivo desse trabalho foi conhecer as espécies de moscas-das-frutas no umbuzeiro e o índice de infestação natural, no município de Petrolina, Pernambuco

Periodically rippled graphene: growth and spatially resolved electronic structure

We studied the growth of an epitaxial graphene monolayer on Ru(0001). The graphene monolayer covers uniformly the Ru substrate over lateral distances larger than several microns reproducing the structural defects of the Ru substrate. The graphene is rippled with a periodicity dictated by the difference in lattice parameter between C and Ru. The theoretical model predict inhomogeneities in the electronic structure. This is confirmed by measurements in real space by means of scanning tunnelling spectroscopy. We observe electron pockets at the higher parts of the ripples.Comment: 5 page

Quintais agroflorestais e segurança alimentar de agricultores familiares no Baixo Irituia, Nordeste paraense.

Os quintais agroflorestais são compostos de uma variedade de espécies vegetais e de pequenos animais, disponibilizando produtos que contribuem para uma dieta diversificada e saudável. O objetivo da pesquisa foi avaliar a contribuição dos quintais agroflorestais para a segurança alimentar em unidades agrícolas familiares no Baixo Irituia, Nordeste Paraense. Através das técnicas de entrevista estruturada e semi-estruturada, turnê guiada, observação direta e recall 24 horas foram realizados um levantamento das espécies (vegetais e animais) nos 18 quintais agroflorestais e a verificação dos alimentos consumidos pelos 30 agricultores familiares, tanto daqueles produzidos nos quintais agroflorestais ou não, quanto daqueles de origem industrializadas. Das 130 espécies, 70 foram plantas alimentícias (das quais 44 frutíferas, 21 hortaliças e 5 de lavoura branca); 31 medicinais; 17 madeireiras; 7 ornamentais e 5 animais alimentícios. Das 70 alimentícias, 94% foram consumidas, especialmente as frutíferas (59%), seguidas das hortaliças (30%) e das de lavoura branca (11%). Os agricultores com quintais agroflorestais tiveram acesso a uma melhor condição nutricional ao consumirem maior quantidade e variedade de alimentos oriundos dos quintais, especialmente as frutas. Produtos industrializados como mortadela, suco artificial e galinha de granja foram consumidos em porcentagens maiores pelos agricultores nos espaços sem quintais agroflorestais. Através da aplicação do teste Student, mostrou-se diferença estatisticamente significativa nas médias da quantidade de alimentos consumidos dos quintais e os industrializados pelos dois grupos de agricultores familiares. Os quintais agroflorestais foram importantes para introduzir variações na dieta alimentar, pois contribuíram na diversificação e complementação alimentar.Editores técnicos: Roberto Porro, Milton Kanashiro, Maria do Socorro Gonçalves Ferreira, Leila Sobral Sampaio e Gladys Ferreira de Sousa

Gravity-driven instability in a spherical Hele-Shaw cell

A pair of concentric spheres separated by a small gap form a spherical Hele-Shaw cell. In this cell an interfacial instability arises when two immiscible fluids flow. We derive the equation of motion for the interface perturbation amplitudes, including both pressure and gravity drivings, using a mode coupling approach. Linear stability analysis shows that mode growth rates depend upon interface perimeter and gravitational force. Mode coupling analysis reveals the formation of fingering structures presenting a tendency toward finger tip-sharpening.Comment: 13 pages, 4 ps figures, RevTex, to appear in Physical Review

Free Magnetic Moments in Disordered Metals

The screening of magnetic moments in metals, the Kondo effect, is found to be quenched with a finite probability in the presence of nonmagnetic disorder. Numerical results for a disordered electron system show that the distribution of Kondo temperatures deviates strongly from the result expected from random matrix theory. A pronounced second peak emerges for small Kondo temperatures, showing that the probability that magnetic moments remain unscreened at low temperatures increases with disorder. Analytical calculations, taking into account correlations between eigenfunction intensities yield a finite width for the distribution in the thermodynamic limit. Experimental consequences for disordered mesoscopic metals are discussed.Comment: RevTex 4.0, 4.3 pages, 4 EPS figures; typos fixed, reference added, final published versio