Decomposition in bunches of the critical locus of a quasi-ordinary map

A polar hypersurface P of a complex analytic hypersurface germ, f=0, can be investigated by analyzing the invariance of certain Newton polyhedra associated to the image of P, with respect to suitable coordinates, by certain morphisms appropriately associated to f. We develop this general principle of Teissier (see Varietes polaires. I. Invariants polaires des singularites d'hypersurfaces, Invent. Math. 40 (1977), 3, 267-292) when f=0 is a quasi-ordinary hypersurface germ and P is the polar hypersurface associated to any quasi-ordinary projection of f=0. We build a decomposition of P in bunches of branches which characterizes the embedded topological type of the irreducible components of f=0. This decomposition is characterized also by some properties of the strict transform of P by the toric embedded resolution of f=0 given by the second author in a paper which will appear in Annal. Inst. Fourier (Grenoble). In the plane curve case this result provides a simple algebraic proof of the main theorem of Le, Michel and Weber in "Sur le comportement des polaires associees aux germes de courbes planes", Compositio Math, 72, (1989), 1, 87-113

Scene-based imperceptible-visible watermarking for HDR video content

This paper presents the High Dynamic Range - Imperceptible Visible Watermarking for HDR video content (HDR-IVW-V) based on scene detection for robust copyright protection of HDR videos using a visually imperceptible watermarking methodology. HDR-IVW-V employs scene detection to reduce both computational complexity and undesired visual attention to watermarked regions. Visual imperceptibility is achieved by finding the region of a frame with the highest hiding capacities on which the Human Visual System (HVS) cannot recognize the embedded watermark. The embedded watermark remains visually imperceptible as long as the normal color calibration parameters are held. HDR-IVW-V is evaluated on PQ-encoded HDR video content successfully attaining visual imperceptibility, robustness to tone mapping operations and image quality preservation

Gestión ambiental en micro, pequeñas y medianas empresas de hospedaje

Las micro, pequeñas y medianas empresas (MIPyMES) mantienen por su propia naturaleza una posición que generalmente las pone en desventaja frente a los grandes corporativos; en el ámbito turístico, éstas son concebidas como entidades ausentes de gestión ambiental e innovación tecnológica. Las MIPYMES hoteleras de Ixtapan de la Sal, un destino turístico tradicional ubicado en el centro de México, afrontan una reconfiguración organizacional para conseguir el mejoramiento del sector; por ello, requieren establecer estrategias que les permita ser más rentables y responsables con el ambiente. El propósito del artículo es evaluar las prácticas ambientales que realizan las MIPyMES de hospedaje, identificando limitaciones y oportunidades en torno a la capacitación, comunicación, control, monitoreo e incorporación de tecnologías. Los resultados demuestran que aun cuando son empresas con escasos recursos económicos y humanos sí llevan a cabo prácticas ambientales, no obstante, el nivel de implementación es todavía elemental y requieren de apoyo para su mejora

Mislabelling in megrims: implications for conservation

Mislabelling of fish catch and commercial seafood products is relatively frequent worldwide and can affect fisheries management exploitation when stock estimates are based on landings. In this study we have analyzed genetically 239 commercial lots of two morphologically similar species of megrims (genus Lepidorhombus) that are caught together in mixed fisheries. A high proportion of mislabelling was detected, suggesting enormous underreported exploitation of one of the species, which can be endangered if the problem persists. These results highlight the urgency of applying currently available species-specific molecular tools in fisheries sciences for preventing biodiversity losses in exploited species

Watermarking of HDR images in the spatial domain with HVS-imperceptibility

This paper presents a watermarking method in the spatial domain with HVS-imperceptibility for High Dynamic Range (HDR) images. The proposed method combines the content readability afforded by invisible watermarking with the visual ownership identification afforded by visible watermarking. The HVS-imperceptibility is guaranteed thanks to a Luma Variation Tolerance (LVT) curve, which is associated with the transfer function (TF) used for HDR encoding and provides the information needed to embed an imperceptible watermark in the spatial domain. The LVT curve is based on the inaccuracies between the non-linear digital representation of the linear luminance acquired by an HDR sensor and the brightness perceived by the Human Visual System (HVS) from the linear luminance displayed on an HDR screen. The embedded watermarks remain imperceptible to the HVS as long as the TF is not altered or the normal calibration and colorimetry conditions of the HDR screen remain unchanged. Extensive qualitative and quantitative evaluations on several HDR images encoded by two widely-used TFs confirm the strong HVSimperceptibility capabilities of the method, as well as the robustness of the embedded watermarks to tone mapping, lossy compression, and common signal processing operations

The Quantum Transverse Field Ising Model on an Infinite Tree from Matrix Product States

We give a generalization to an infinite tree geometry of Vidal's infinite time-evolving block decimation (iTEBD) algorithm for simulating an infinite line of quantum spins. We numerically investigate the quantum Ising model in a transverse field on the Bethe lattice using the Matrix Product State ansatz. We observe a second order phase transition, with certain key differences from the transverse field Ising model on an infinite spin chain. We also investigate a transverse field Ising model with a specific longitudinal field. When the transverse field is turned off, this model has a highly degenerate ground state as opposed to the pure Ising model whose ground state is only doubly degenerate.Comment: 28 pages, 23 figures, PDFlate

Bacterial outer membrane vesicles and vaccine applications

Vaccines based on outer membrane vesicles (OMV) were developed more than 20 years ago against Neisseria meningitidis serogroup B. These nano-sized structures exhibit remarkable potential for immunomodulation of immune responses and delivery of “self” meningococcal antigens or unrelated antigens incorporated into the vesicle structure. This paper reviews different applications in OMV Research and Development (R&D) and provides examples of OMV developed and evaluated at the Finlay Institute in Cuba. A Good Manufacturing Practice (GMP) process was developed at the Finlay Institute to produce OMV from N. meningitidis serogroup B (dOMVB) using detergent extraction. Subsequently, OMV from N. meningitidis, serogroup A (dOMVA), serogroup W (dOMVW) and serogroup X (dOMVX) were obtained using this process. More recently, the extraction process has also been applied effectively for obtaining OMV on a research scale from Vibrio cholerae (dOMVC), Bordetella pertussis (dOMVBP), Mycobacterium smegmatis (dOMVSM) and BCG (dOMVBCG). The immunogenicity of the OMV have been evaluated for specific antibody induction, and together with functional bactericidal and challenge assays in mice have shown their protective potential. dOMVB has been evaluated with non-self neisserial antigens, including with a herpes virus type 2 glycoprotein, ovalbumin and allergens. In conclusion, OMV are proving to be more versatile than first conceived and remain an important technology for development of vaccine candidates. - See more at: http://journal.frontiersin.org/Journal/10.3389/fimmu.2014.00121/abstract#sthash.MwqUyZQ1.dpu

Criticality without frustration for quantum spin-1 chains

Frustration-free (FF) spin chains have a property that their ground state minimizes all individual terms in the chain Hamiltonian. We ask how entangled the ground state of a FF quantum spin-s chain with nearest-neighbor interactions can be for small values of s. While FF spin-1/2 chains are known to have unentangled ground states, the case s=1 remains less explored. We propose the first example of a FF translation-invariant spin-1 chain that has a unique highly entangled ground state and exhibits some signatures of a critical behavior. The ground state can be viewed as the uniform superposition of balanced strings of left and right parentheses separated by empty spaces. Entanglement entropy of one half of the chain scales as log(n)/2 + O(1), where n is the number of spins. We prove that the energy gap above the ground state is polynomial in 1/n. The proof relies on a new result concerning statistics of Dyck paths which might be of independent interest.Comment: 11 pages, 2 figures. Version 2: minor changes in the proof of Lemma