2,662 research outputs found
PEDESTRIAN PATHFINDING in URBAN ENVIRONMENTS: PRELIMINARY RESULTS
With the rise of urban population, many initiatives are focused upon the smart city concept, in which mobility of citizens arises as one of the main components. Updated and detailed spatial information of outdoor environments is needed to accurate path planning for pedestrians, especially for people with reduced mobility, in which physical barriers should be considered. This work presents a methodology to use point clouds to direct path planning. The starting point is a classified point cloud in which ground elements have been previously classified as roads, sidewalks, crosswalks, curbs and stairs. The remaining points compose the obstacle class. The methodology starts by individualizing ground elements and simplifying them into representative points, which are used as nodes in the graph creation. The region of influence of obstacles is used to refine the graph. Edges of the graph are weighted according to distance between nodes and according to their accessibility for wheelchairs. As a result, we obtain a very accurate graph representing the as-built environment. The methodology has been tested in a couple of real case studies and Dijkstra algorithm was used to pathfinding. The resulting paths represent the optimal according to motor skills and safety
Tensorial perturbations in the bulk of inflating brane worlds
In this paper we consider the stability of some inflating brane-world models
in quantum cosmology. It is shown that whereas the singular model based on the
construction of inflating branes from Euclidean five-dimensional anti-de Sitter
space is unstable to tensorial cosmological perturbations in the bulk, the
nonsingular model which uses a five-dimensional asymptotically anti-de Sitter
wormhole to construct the inflating branes is stable to these perturbations.Comment: 4 pages, RevTex, to appear in Phys. Rev.
Pasture Production After Sewage Sludge and Liming Application on Highlands in North West Spain
In recent years, a sewage sludge surplus has been created in the EU countries, due to the Urban Waste Water Treatment Directive 91/271/CEE. Therefore, it is necessary to find adequate disposal for these residues in accordance with EU policy. Organic matter and nutrient sewage sludge contain principally N, indicating that it could be used as fertiliser. The main risk of this residue is its heavy metal content, whose solubility is usually increased as soil pH declines. The objective of this experiment was to determine the effect of liming and sewage sludge application on pasture production in a silvopastoral system located on acid soi
Genomic Evolution of Two Acinetobacter baumannii Clinical Strains from ST-2 Clones Isolated in 2000 and 2010 (ST-2_clon_2000 and ST-2_clon_2010)
Acinetobacter baumannii is a successful nosocomial pathogen due to its ability to persist in hospital environments by acquiring
mobile elements such as transposons, plasmids, and phages. In this study, we compared two genomes of A. baumannii clinical
strains isolated in 2000 (ST-2_clon_2000) and 2010 (ST-2_clon_2010) from GenBank project PRJNA308422
Heterologous expression of AtNPR1 gene in olive for increasing fungal tolerance
The NPR1 gene encodes a key component of SAR signaling mediated by salicylic acid (SA). After a pathogen infection, the accumulation of SA releases NPR1 monomers in the cytosol that are translocated to the nucleus, activating the expression of pathogenesis-related (PR) genes. Overexpression of NPR1 has conferred resistance to fungal, viral and bacterial pathogens in several plant species. The aim of this research was to generate transgenic olive plants expressing the gene AtNPR1 from Arabidopsis thaliana to obtain material resistant to fungal pathogens. Three transgenic lines expressing AtNPR1 gene under the control of the constitutive promoter CaMV35S were obtained following the protocol of Torreblanca et al. (2010), using an embryogenic line derived from a seed of cv. Picual. Level of AtNPR1 expression in transgenic calli varied greatly among the different lines, being higher in the line NPR1-780. The elicitation of embryogenic calli in liquid medium with AS did not increase endochitinase activity, a PR protein. However, jasmonic acid induced a transient increase in chitinase activity after 24 h of treatment in all the lines, being the increment higher in transgenic NPR1 than in control. After maturation and germination of transgenic somatic embryos, plants were micropropagated and acclimated to ex vitro conditions. The expression of AtNPR1 did not alter the growth of transgenic plants neither in vitro nor in the greenhouse. Experiments are in progress to determine the resistance of transgenic AtNPR1 plants to V. dalihae and R. necatrix.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech.
Research projects: Plan Nacional AGL2014-52518-C2-1-R; AGL2017-83368-C2-1-R and Junta de Andalucía P11-AGR799
Supporting autonomy in physical education: Perception versus reality.
Esta investigación se centró, por una parte en la percepción de apoyo a la autonomía en las clases de Educación física, que tienen tanto el alumnado como el profesorado, y por otra, en la coherencia entre percepción y la realidad observada en las clases. Se aplicaron dos escalas al profesorado y al alumnado con el objeto de conocer con qué frecuencia se producen comportamientos instructivos favorables al desarrollo de la autonomía, y se observaron y grabaron en video clases impartidas por el profesorado. Los resultados muestran que la frecuencia de los comportamientos instructivos de apoyo a la autonomía durante la intervención de enseñanza es significativamente menor que la percibida por el alumnado y el profesorado. La realidad observada muestra un perfil de profesorado con gran margen de mejora en comportamientos como: calidad de la comunicación, funcionalidad de las tareas, fomento del pensamiento del alumnado, situaciones en las que el alumnado pueda expresar su opinión sobre las tareas y motivación intrínsecaThis investigation, on the one hand it focuses on students´ and teachers´ perception about autonomy support during Physical Education instruction, and on the other hand, in the coherence between perception and reality observed in the classes. Two scales were administered to determine the frequency of instructional behaviors favoring the development of autonomy, and teacher´s classes were observed and videotaped. The results show that the observed frequency of instructional behavior favoring autonomy support during classes is significantly lower than that perceived by students and teachers. The observed reality reveals a teacher profile with room for improvement in behaviors such as: communication quality, task functionality, promotion of students’ thinking, creation of situations in which students can express their opinions of the tasks, and increasing intrinsic motivationEl presente artículo forma parte del estudio realizado con la financiación del proyecto SEJ2007-672687/EDU del Ministerio de Ciencia e Innovació
(−)-Istanbulin A
The title compound (systematic name: 9a-hydroxy-3,4a,5-trimethyl-4a,6,7,8a,9,9a-hexahydro-4H,5H-naphtho[2,3-b]furan-2,8-dione), C15H20O4, is a sesquiterpene lactone showing the typical eremophilanolide skeleton, which has been isolated from the plant Senecio candidans collected in the Chilean Magallanes region. The present study confirms the atomic connectivity assigned on the basis of 1H and 13C NMR spectroscopy, as well as the relative stereochemistry of the 4α-methyl,5α-methyl,8β-hydroxy,10β-H unit. The crystal structure is stabilized by intermolecular O—H⋯O hydrogen bonds involving the hydroxy group as donor and the oxo group as acceptor, giving chains along the a axis. The absolute structure was not determined because of the lack of suitable anomalous scatters
Mulching and seeding treatments for post-fire stabilization techniques in Laza (NW Spain): medium-term effects on soil quality and effectiveness
The impact of fire and different post-fire stabilisation treatments like mulching and seeding on some selected physical, chemical biochemical and microbiological properties as well as the efficacy of these treatments on control of post-fire erosion was evaluated in a burnt area affected by a high severity wildfire located in Laza (NW Spain). Soil samples were collected from the A horizon (0-2 cm) of the burnt soil 8 and 12 months after the wildfire as well as from the unburnt soil located in an adjacent plot used as control; sediments were periodically collected after precipitation events in the burnt soil with and without different post-fire stabilisation treatments. The results clearly showed that a significant medium-term impact of the wildfire on most soil properties analyzed was still observed 12 months after the fire event and that mulching and seeding treatments did not affect the overall soil quality (physical, chemical, biochemical and microbiological properties) of this burned soil. Sediments data indicated that both stabilisation treatments were effective to control post-fire erosion since, compared to the burnt control, soil losses were reduced by 85% in the mulching treatment and by 30% in the seeding treatment
Recovery of a soil under different vegetation one year after a high intensity wildfire
Studies on soil recovery in fragile ecosystems following high intensity wildfires are scarce. The aim of the present investigation is to evaluate the impact of a high intensity wildfire in an ecosystem under different vegetation (shrubland and pinewood) located at Vilardevós (Galicia, NW Spain) and highly susceptible to suffer soil erosion due to the steep relief and high erositivity of the rainfall. Soil samples were collected from the A horizon (0-5 cm) 1 year after the fire and soil quality was evaluated by analysis of several physical, chemical and biochemical properties measured in the fraction < 2 mm. The results showed marked effects of the wildfire on most properties analyzed even 1 year after the fire; however, a different effect both in the trend (positive, negative) and magnitude were observed, depending on the soil property analyzed. In general, the sensitivity to detect fire induced changes followed the order: biochemical properties > chemical properties > physical properties. The data also showed that the fire impact was different depending on the soil vegetation considered (shrubland and pinewood). Moreover, the data confirmed the slow soil recovery in this fragile ecosystem and, therefore, the need of adopting post-fire stabilisation and rehabilitation treatments in order to minimize the post-fire erosion and soil degradation
Testing models with non-minimal Higgs sector through the decay t->q+WZ
We study the contribution of charged Higgs boson to the rare decay of the top
quark t->q+WZ (q=d,s,b) in models with Higgs sector that includes doublets and
triplets. Higgs doublets are needed to couple charged Higgs with quarks,
whereas the Higgs triplets are required to generate the non-standard vertex HWZ
at tree-level. It is found that within a model that respect the custodial SU(2)
symmetry and avoids flavour changing neutral currents by imposing discrete
symmetries, the decay mode t->b+WZ, can reach a branching ratio of order
0.0178, whereas the decay modes t->(d,s)+WZ, can reach a similar branching
ratio in models where flavour changing neutral currents are suppressed by
flavour symmetries.Comment: Typeset using REVTEX and EPSF, 5 pag, 2 figure
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