2,546 research outputs found

    Review of \u3ci\u3eWar of a Thousand Deserts\u3c/i\u3e

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    Among the challenges that battered Mexico in the decades following independence was raiding from independent Indian groups that increasingly found plunder preferable to peace. In this ambitious and erudite work Brian DeLay argues that it was exhaustion from fighting Comanches, Apaches, and Kiowas among northern Mexicans that largely made for the easy victory of the United States in its 1846- 1847 war of conquest against Mexico. As the evidence mounted for American policy makers that the Mexican government was not only unable to develop its northern territories properly but was incapable of defending them, the logic of incorporating Texas into the Union and claiming California and New Mexico became manifest

    La deformabilidad del suelo "in situ". Un método para la interpretación conjunta de los ensayos de laboratorio y de campo

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    Los ensayos de laboratorio y de campo que permiten evaluar la defonnabilidad del terreno conducen generalmente a resultados poco acordes entre sí. La interpretación conjunta de los resultados de ambos tipos de ensayos es un procedimiento habitual para el establecimiento de leyes constitutivas tensióndeformación del suelo "in situ", con validez para estados tensionales variables dentro de límites determinados. El ensayo "in situ" estudiado en este caso (placa de carga) se reproduce de forma numérica utilizando un modelo de cálculo capaz de admitir la ley constitutiva establecida en el laboratorio (modelo hiperbólico) y, posteriormente, se comparan sus resultados con los del ensayo real. Para simular el ensayo de carga se ha desarrollado un modelo simplificado que permite tener en cuenta la respuesta heterogénea del suelo debida a la existencia de presiones de confinamiento variables y la no linealidad entre tensiones y deformaciones para un confinamiento dado. El modelo simplificado se ha desarrollado en lenguaje FORTRAN ("PLACAR"), consiguiéndose un programa de utilización sencilla y coste reducido. Los resultados se han contrastado con un modelo de elementos finitos. Finalmente, se incluyen dos ejemplos de aplicación práctica. En el primero la interpretación conjunta resulta eficaz y se analiza la extrapolación de los resultados a las dimensiones de las cimentaciones reales. En cambio, en el segundo ejemplo la interpretación no tiene utilidad práctica.Peer Reviewe

    Differential activity of Drosophila Hox genes induces myosin expression and can maintain compartment boundaries

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    Compartments are units of cell lineage that subdivide territories with different developmental potential. In Drosophila, the wing and haltere discs are subdivided into anterior and posterior (A/P) compartments, which require the activity of Hedgehog, and into dorsal and ventral (D/V) compartments, needing Notch signaling. There is enrichment in actomyosin proteins at the compartment boundaries, suggesting a role for these proteins in their maintenance. Compartments also develop in the mouse hindbrain rhombomeres, which are characterized by the expression of different Hox genes, a group of genes specifying different structures along their main axis of bilaterians. We show here that the Drosophila Hox gene Ultrabithorax can maintain the A/P and D/V compartment boundaries when Hedgehog or Notch signaling is compromised, and that the interaction of cells with and without Ultrabithorax expression induces high levels of non-muscle myosin II. In the absence of Ultrabithorax there is occasional mixing of cells from different segments. We also show a similar role in cell segregation for the Abdominal-B Hox gene. Our results suggest that the juxtaposition of cells with different Hox gene expression leads to their sorting out, probably through the accumulation of non-muscle myosin II at the boundary of the different cell territories. The increase in myosin expression seems to be a general mechanism used by Hox genes or signaling pathways to maintain the segregation of different groups of cells.Peer Reviewe

    Complexity measurement and characterization of 360-degree content

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    The appropriate characterization of the test material, used for subjective evaluation tests and for benchmarking image and video processing algorithms and quality metrics, can be crucial in order to perform comparative studies that provide useful insights. This paper focuses on the characterisation of 360-degree images. We discuss why it is important to take into account the geometry of the signal and the interactive nature of 360-degree content navigation, for a perceptual characterization of these signals. Particularly, we show that the computation of classical indicators of spatial complexity, commonly used for 2D images, might lead to different conclusions depending on the geometrical domain use

    Complexity measurement and characterization of 360-degree content

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    The appropriate characterization of the test material, used for subjective evaluation tests and for benchmarking image and video processing algorithms and quality metrics, can be crucial in order to perform comparative studies that provide useful insights. This paper focuses on the characterisation of 360-degree images. We discuss why it is important to take into account the geometry of the signal and the interactive nature of 360-degree content navigation, for a perceptual characterization of these signals. Particularly, we show that the computation of classical indicators of spatial complexity, commonly used for 2D images, might lead to different conclusions depending on the geometrical domain use

    Evaluation of adjuvant activity of fractions derived from Agaricus blazei, when in association with the recombinant LiHyp1 protein, to protect against visceral leishmaniasis

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    © 2015 Elsevier Inc. The development of effective prophylactic strategies to prevent leishmaniasis has become a high priority. No less important than the choice of an antigen, the association of an appropriate adjuvant is necessary to achieve a successful vaccination, as the majority of the tested antigens contain limited immunogenic properties, and need to be supplemented with immune response adjuvants in order to boost their immunogenicity. However, few effective adjuvants that can be used against leishmaniasis exist on the market today; therefore, it is possible to speculate that the research aiming to identify new adjuvants could be considered relevant. Recently, Agaricus blazei extracts have proved to be useful in enhancing the immune response to DNA vaccines against some diseases. This was based on the Th1 adjuvant activity of the polysaccharide-rich fractions from this mushroom. In this context, the present study evaluated purified fractions derived from Agaricus blazei as Th1 adjuvants through in vitro assays of their immune stimulation of spleen cells derived from naive BALB/c mice. Two of the tested six fractions (namely F2 and F4) were characterized as polysaccharide-rich fractions, and were able to induce high levels of IFN-γ, and low levels of IL-4 and IL-10 in the spleen cells. The efficacy of adjuvant action against L. infantum was evaluated in BALB/c mice, with these fractions being administered together with a recombinant antigen, LiHyp1, which was previously evaluated as a vaccine candidate, associated with saponin, against visceral leishmaniasis (VL). The associations between LiHyp1/F2 and LiHyp1/F4 were able to induce an in vivo Th1 response, which was primed by high levels of IFN-γ, IL-12, and GM-CSF, by low levels of IL-4 and IL-10; as well as by a predominance of IgG2a antibodies in the vaccinated animals. After infection, the immune profile was maintained, and the vaccines proved to be effective against L. infantum. The immune stimulatory effects in the BALB/c mice proved to be similar when comparing the F2 and F4 fractions with a known Th1 adjuvant (saponin), though animals vaccinated with saponin did present a slight to moderate inflammatory edema on their hind footpads. In conclusion, the F2 and F4 fractions appear to induce a Th1-type immune response and, in this context, they could be evaluated in association with other protective antigens against Leishmania, as well as in other disease models.Instituto Nacional de Ciencia e Tecnologia em Nano-biofarmaceutica (INCT-Nanobiofar), FAPEMIG (CBB-APQ-00496-11 and CBB-APQ-00819-12), and CNPq (APQ-472090/2011-9, RHAE-456287/2012-4, APQ-482976/2012-8 and APQ-488237/2013-0).Peer Reviewe
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