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Vision is the sense that provides precise information about one’s position in the environment in relation to objects. The visual system is essential to guide people safely when moving around in the environment. The perception that an individual gets from a particular scene of her/his surroundings is accomplished by eye movements. The current study aims to identify differences in visual strategies between 15 women and 15 men within the age range of 18-24 years, who have been given a task to walk through an obstacle course drawn on the laboratory´s floor. They should start and finish at a predefined location. Twelve pylons were used as obstacles to be avoided during the walking.The participants' eye movements were recorded using the Mobile Eye model 1.35. The Wilcoxon-Mann-Whitney Test was used for the statistical analysis. Significant differences occurred between men and women, in the duration of fixations: the men spend more time observing the finishing area than women (z=-1.929, p=.054); and in the number of fixations: before starting the task, the men fixate more often the middle phase of the obstacle course (z=-2.085, p=.037). Once they commence, the women fixate more the points outside the obstacle course than the men (z=-2.093, p=.036).

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Este trabajo tiene como objetivo definir la nueva concepción y práctica de la comunicación popular alternativa, particularmente en las instituciones del Ecuador, a partir del estudio y comprensión de las transformaciones experimentadas en las últimas décadas. De una comunicación lineal y manipuladora, que otorga absoluto poder a los medios, de una comunicación politizada e inscrita en la lucha de clases, se advierte el cambio a una comunicación plural y ciudadana que recupera al sujeto y que reconoce en él las múltiples mediaciones sociales y culturales. La investigación sobre los determinantes teóricos e históricos que propiciaron dicho cambio es lo que sustenta este trabajo. La autora indaga sobre la manera en que la comunicación popular fue recorriendo tres paradigmas -cuya configuración, sin ser rígida y mucho menos la única, obedece a fines de esta investigación-: el del cambio social y modernización de los pueblos, el de dominación-subordinación, y el de las mediaciones sociales y culturales. Este recorrido obliga a preguntarnos qué es actualmente la comunicación popular y cómo se desarrollan las prácticas comunicativas en un nuevo contexto caracterizado por las crecientes urbanizaciones, la globalización de la cultura, la reorientación del modelo económico, la irrupción de nuevas tecnologías, y sus consecuencias expresadas en la conformación de comunidades "desterritorializadas", la revitalización de los particularismos y la fragilidad de las monoidentidades.

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Trace elements may present an environmental hazard in the vicinity of mining and smelting activities. However, the factors controlling trace element distribution in soils around ancient and modem mining and smelting areas are not always clear. Tharsis, Riotinto and Huelva are located in the Iberian Pyrite Belt in SW Spain. Tharsis and Riotinto mines have been exploited since 2500 B.C., with intensive smelting taking place. Huelva, established in 1970 and using the Flash Furnace Outokumpu process, is currently one of the largest smelter in the world. Pyrite and chalcopyrite ore have been intensively smelted for Cu. However, unusually for smelters and mines of a similar size, the elevated trace element concentrations in soils were found to be restricted to the immediate vicinity of the mines and smelters, being found up to a maximum of 2 kin from the mines and smelters at Tharsis, Riotinto and Huelva. Trace element partitioning (over 2/3 of trace elements found in the residual immobile fraction of soils at Tharsis) and soil particles examination by SEM-EDX showed that trace elements were not adsorbed onto soil particles, but were included within the matrix of large trace element-rich Fe silicate slag particles (i.e. 1 min circle divide at least 1 wt.% As, Cu and Zn, and 2 wt.% Pb). Slag particle large size (I mm 0) was found to control the geographically restricted trace element distribution in soils at Tharsis, Riotinto and Huelva, since large heavy particles could not have been transported long distances. Distribution and partitioning indicated that impacts to the environment as a result of mining and smelting should remain minimal in the region. (c) 2006 Elsevier B.V. All rights reserved.

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Mineralised organic remains (including apple pips and cereal grains) collected during the ongoing excavations of Insula IX at the Roman town of Silchester, Hampshire have been analysed by a combination of SEM-EDX, powder XRD and IR spectroscopy. The experiments included mapping experiments using spatially resolved versions of each technique. IR and powder XRD mapping have been carried out utilising the synchrotron source at The Daresbury Laboratory oil stations 11.1 and 9.6. It is concluded that these samples are preserved by rapid mineralisation in the carbonate-substituted calcium phosphate mineral, dahllite. The rapid mineralisation leads to excellent preservation of the samples and a small crystal size. The value of IR spectroscopy in studying materials like this where the crystal size is small is demonstrated. A comparison is made between the excellent preservation seen in this context and the much poorer preservation of mineralised remains seen in Context 5276 or Cesspit 5251. Comments on the possible mechanism of mineralisation of these samples are made. (C) 2008 Elsevier B.V.. All rights reserved.

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Ecological indicators are taxa that are affected by, and indicate effects of, anthropogenic environmental stress or disturbance on ecosystems. There is evidence that some species of soil macrofauna (i.e. diameter > 2 min) constitute valuable biological indicators of certain types of soil perturbations. This study aims to determine which level of taxonomic resolution, (species, family or ecological group) is the best to identify indicator of soil disturbance. Macrofauna were sampled in a set of sites encompassing different land-use systems (e.g. forests, pastures, crops) and different levels of pollution. Indicator taxa were sought using the IndVal index proposed by Dufrene and Legendre [Dufrene, M., Legendre, P., 1997. Species assemblages and indicator species: the need for a flexible asymetrical approach. Ecological Monographs 67, 345-3661. This approach is based on a hierarchical typology of sites. The index value changes along the typology and decreases (increases) for generalist (specialist) faunal units (species, families or ecological groups). Of the 327 morphospecies recorded, 19 were significantly associated with a site type or a group of sites (5.8%). Similarly, species were aggregated to form 59 families among which 17 (28.8%) displayed a significant indicator value. Gathering species into 28 broad ecological assemblages led to 14 indicator groups (50%). Beyond the simple proportion of units having significant association with a given level of the site typology, the proportion of specialist and generalist groups changed dramatically when the level of taxonomic resolution was altered. At the species level 84% of the indicator units were specialist, whereas this proportion decreased to 70 and 43% when families and ecological groups were considered. Because specialist groups are the most interesting type of indicators either in terms of conservation or for management purposes we come to the conclusion that the species level is the most accurate taxonomic level in bioindication studies although it requires a high amount of labour and operator knowledge and is time-consuming. (c) 2005 Published by Elsevier Ltd.

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Seeds of 39 seed lots of a total of twelve different crops were stored hermetically in a wide range of air-dry environments (2-25% moisture content at 0-50 degrees C), viability assessed periodically, and the seed viability equation constants estimated. Within a species, estimates of the constants which quantify absolute longevity (K-E) and the relative effects on longevity of moisture content (C-W) and temperature (C-H and C-Q) did not differ (P >0.05 to P >0.25) among lots. Comparison among the 12 crops provided variant estimates of K-E and C-W (P< 0.01), but common values of C-H and C-Q (0.0322 and 0.000454, respectively, P >0.25). Maize (Zea mays) provided the greatest estimate of K-E (9.993, s.e.= 0.456), followed by sorghum (Sorghum bicolor) (9.381, s.e. 0.428), pearl millet (Pennisetum typhoides) (9.336, s.e.= 0.408), sugar beet (Beta vulgaris) (8.988, s.e.= 0.387), African rice (Oryza glaberrima) (8.786, s.e.= 0.484), wheat (Triticum aestivum) (8.498, s.e.= 0.431), foxtail millet (Setaria italica) (8.478, s.e.= 0.396), sugarcane (Saccharum sp.) (8.454, s.e.= 0.545), finger millet (Eleusine coracana) (8.288, s.e.= 0.392), kodo millet (Paspalum scrobiculatum) (8.138, s.e.= 0.418), rice (Oryza sativa) (8.096, s.e.= 0.416) and potato (Solanum tuberosum) (8.037, s.e.= 0.397). Similarly, estimates of C-W were ranked maize (5.993, s.e.= 0.392), pearl millet (5.540, s.e.= 0.348), sorghum (5.379, s.e.=0.365), potato (5.152, s.e.= 0.347), sugar beet (4.969, s.e.= 0.328), sugar cane (4.964, s.e.= 0.518), foxtail millet (4.829, s.e.= 0.339), wheat (4.836, s.e.= 0.366), African rice (4.727, s.e.= 0.416), kodo millet (4.435, s.e.= 0.360), finger millet (4.345, s.e.= 0.336) and rice (4.246, s.e.= 0.355). The application of these constants to long-term seed storage is discussed.

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Platelet endothelial cell adhesion molecule-1 (PECAM-1) inhibits platelet response to collagen and may also inhibit two other major platelet agonists ADP and thrombin although this has been less well explored. We hypothesized that the combined effect of inhibiting these three platelet activating pathways may act to significantly inhibit thrombus formation. We demonstrate a negative relationship between PECAM-1 surface expression and platelet response to cross-linked collagen related peptide (CRP-XL) and ADP, and an inhibitory effect of PECAM-1 clustering on platelet response to CRP-XL, ADP and thrombin. This combined inhibition of multiple signaling pathways results in a marked reduction in thrombus formation. (C) 2009 Federation of European Biochemical Societies. Published by Elsevier B. V. All rights reserved.

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It has previously been shown that experimental infections of the parasitic trematode Schistosoma mansoni, the adult worms of which reside in the blood stream of the mammalian host, significantly reduced atherogenesis in apolipoprotein E gene knockout (apoE(-/-)) mice. These effects occurred in tandem with a lowering of serum total cholesterol levels in both apoE(-/-) and random-bred laboratory mice and a beneficial increase in the proportion of HDL to LDL cholesterol. To better understand how the parasitic infections induce these effects we have here investigated the involvement of adult worms and their eggs on lipids in the host. Our results indicate that the serum cholesterol-lowering effect is mediated by factors released from S. mansoni eggs, while the presence of adult worms seemed to have had little or no effect. It was also observed that high levels of lipids, particularly triacylglycerols and cholesteryl esters, present in the uninfected livers of both random-bred and apoE(-/-) mice fed a high-fat diet were not present in livers of the schistosome-infected mice. (C) 2009 Elsevier Ireland Ltd. All rights reserved.