Linking Shade Coffee Certification To Biodiversity Conservation: Butterflies And Birds In Chiapas, Mexico

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/117232/1/eap2004143642.pd

An Index Of Management Intensity For Coffee Agroecosystems To Evaluate Butterfly Species Richness

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/117238/1/eap20031351491.pd

Pulse propagation in decorated granular chains: An analytical approach

We study pulse propagation in one-dimensional chains of spherical granules decorated with small grains placed between large granules. The effect of the small granules can be captured by replacing the decorated chains by undecorated chains of large granules of appropriately renormalized mass and effective interaction between the large granules. This allows us to obtain simple analytic expressions for the pulse propagation properties using a generalization of the binary collision approximation introduced in our earlier work [Phys. Rev. E in print (2009); Phys. Rev. E {\bf 69}, 037601 (2004)]Comment: 10 pages and 12 figure

Observation of two-wave structure in strongly nonlinear dissipative granular chains

In a strongly nonlinear viscous granular chain under conditions of loading that exclude stationary waves (e.g., impact by a single grain) we observe a pulse that consists of two interconnected but distinct parts. One is a leading narrow "primary pulse" with properties similar to a solitary wave in a "sonic vacuum." It arises from strong nonlinearity and discreteness in the absence of dissipation, but now decays due to viscosity. The other is a broad, much more persistent shock-like "secondary pulse" trailing the primary pulse and caused by viscous dissipation. The medium behind the primary pulse is transformed from a "sonic vacuum" to a medium with finite sound speed. When the rapidly decaying primary pulse dies, the secondary pulse continues to propagate in the "sonic vacuum," with an oscillatory front if the viscosity is relatively small, until its eventual (but very slow) disintegration. Beyond a critical viscosity there is no separation of the two pulses, and the dissipation and nonlinearity dominate the shock-like attenuating pulse which now exhibits a nonoscillatory front

Magnetic field-induced insulating behavior in highly oriented pyrolitic graphite

We propose an explanation for the apparent semimetal-insulator transition observed in highly oriented pyrolitic graphite in the presence of magnetic field perpendicular to the layers. We show that the magnetic field opens an excitonic gap in the linear spectrum of the Coulomb interacting quasiparticles, in a close analogy with the phenomenon of dynamical chiral symmetry breaking in the relativistic theories of the 2+1-dimensional Dirac fermions. Our strong-coupling appoach allows for a non-perturbative description of the corresponding critical behavior

NMR C-NOT gate through Aharanov-Anandan's phase shift

Recently, it is proposed to do quantum computation through the Berry's phase(adiabatic cyclic geometric phase) shift with NMR (Jones et al, Nature, 403, 869(2000)). This geometric quantum gate is hopefully to be fault tolerant to certain types of errors because of the geometric property of the Berry phase. Here we give a scheme to realize the NMR C-NOT gate through Aharonov-Anandan's phase(non-adiabatic cyclic phase) shift on the dynamic phase free evolution loop. In our scheme, the gate is run non-adiabatically, thus it is less affected by the decoherence. And, in the scheme we have chosen the the zero dynamic phase time evolution loop in obtaining the gepmetric phase shift, we need not take any extra operation to cancel the dynamic phase.Comment: 5 pages, 1 figur

Spatially extended emission around the Cepheid RS Puppis in near-infrared hydrogen lines. Adaptive optics imaging with VLT/NACO

It has been recently discovered that Cepheids harbor circumstellar envelopes (CSEs). RS Pup is the Cepheid that presents the most prominent circumstellar envelope known, the origin of which is not yet understood. Our purpose is to estimate the flux contribution of the CSE around RS Pup at the one arcsecond scale (~2000 AU) and to investigate its geometry, especially regarding asymmetries, to constrain its physical properties. We obtained near-infrared images in two narrow band filters centered on \lambda = 1.644 and 2.180 \mu m (NB 1.64 and IB 2.18, respectively) that comprise two recombination lines of hydrogen: the 12-4 and 7-4 (Brackett \gamma) transitions, respectively. We used NACO's cube mode observations in order to improve the angular resolution with the shift-and-add technique, and to qualitatively study the symmetry of the spatially extended emission from the CSE with a statistical study of the speckle noise. We probably detect at a 2\sigma level an extended emission with a relative flux (compared with the star in the same filter) of 38 $\pm$ 17% in the NB 1.64 filter and 24 $\pm$ 11% in the IB 2.18 filter. This emission is centered on RS Pup and does not present any detectable asymmetry. We attribute the detected emission to the likely presence of an hydrogen envelope surrounding the star

Parallel

In this paper we present Parallel, a videogame with a powerful story of mystery, suspense and puzzle-solving. Parallel provides an interactive storyline where the actions players take throughout the game will define the course of the story and alter events. The environment created in the game is unique and it was improved from testing with several subjects on a prototype of the tutorial. Parallel’s main potential is the sense of immersion it can provide with its obscure environment, dynamic dialogs using an artificial intelligent agent and its interactive storyline.info:eu-repo/semantics/acceptedVersio

Cooling process for inelastic Boltzmann equations for hard spheres, Part II: Self-similar solutions and tail behavior

We consider the spatially homogeneous Boltzmann equation for inelastic hard spheres, in the framework of so-called constant normal restitution coefficients. We prove the existence of self-similar solutions, and we give pointwise estimates on their tail. We also give general estimates on the tail and the regularity of generic solutions. In particular we prove Haff 's law on the rate of decay of temperature, as well as the algebraic decay of singularities. The proofs are based on the regularity study of a rescaled problem, with the help of the regularity properties of the gain part of the Boltzmann collision integral, well-known in the elastic case, and which are extended here in the context of granular gases.Comment: 41 page