Dispersal in the Desert: Genetic Diversity and Population Structure of the Guinea Baboon (Papio papio) in Mauritania

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Deforming tachyon kinks and tachyon potentials

In this paper we investigate deformation of tachyon potentials and tachyon kink solutions. We consider the deformation of a DBI type action with gauge and tachyon fields living on D1-brane and D3-brane world-volume. We deform tachyon potentials to get other consistent tachyon potentials by using properly a deformation function depending on the gauge field components. Resolutions of singular tachyon kinks via deformation and applications of deformed tachyon potentials to scalar cosmology scenario are discussed.Comment: To appear in JHEP, 19 pages, 5 eps figures, minor changes and one reference adde

Ferramentas Educacionais e Análise Intervencional da Aprendizagem Significativa: Es tudos de Casos Aplicados no Ensino da Física Acústica na Disciplina de Conforto Ambiental

It is of fundamental importance the mastery of Physics contents for the understanding of Acoustic Comfort. In this sense, it is up to the teacher to become aware of students' prior knowledge, to give a new meaning to the cognitive structures that make it possible to transform their difficulties into learning potential. In this work, educational teaching / learning interventions were developed and focused on the Theory of Meaningful Learning. These case studies were carried out with several students in different classes in the same program. In addition to the pre- and post-intervention questionnaire, Computational Educational Tools were used in order to assess the previous concepts and the effectiveness and efficiency of the provided pedagogical intervention. Satisfactory results were obtained with a reduction of about 250% in terms of alternative conceptions to the scientific knowledge previously detected in the participating volunteer students. The analysis was based on the approach of Ausubel and collaborators' Meaningful Learning theories, contextualized to the content of Acoustic Physics and applied in the classes of the Environmental Comfort course in the Civil Engineering and Civil Construction Technology programs from 2012 to 2018

Numerical Model of Constrained Wave Energy Hyperbaric Converter under Full-Scale Sea Wave Conditions

Funding Information: This research was funded by Fundação para a Ciência e a Tecnologia (FCT.IP) through the grant UIDB/00667/2020 (UNIDEMI). This work was also supported by the project SURVIWEC PID2020-113245RB-I00 and by the project ED431C 2021/44 “Programa de Consolidación e Estructuración de Unidades de Investigación Competitivas”. This study forms part of the Marine Science programme (ThinkInAzul) supported by Ministerio de Ciencia e Innovación and Xunta de Galicia with funding from the European Union NextGenerationEU (PRTR-C17.I1) and European Maritime and Fisheries Fund. Funding Information: The authors acknowledge Fundação para a Ciência e a Tecnologia (FCT.IP) for its financial support through the grant UIDB/00667/2020 (UNIDEMI). This work was also supported by the project SURVIWEC PID2020-113245RB-I00 financed by MCIN/AEI/10.13039/501100011033 and by the project ED431C 2021/44 ”Programa de Consolidación e Estructuración de Unidades de Investigación Competitivas” financed by Xunta de Galicia, Consellería de Cultura, Educación e Universidade. This study forms part of the Marine Science programme (ThinkInAzul) supported by Ministerio de Ciencia e Innovación and Xunta de Galicia with funding from the European Union NextGenerationEU (PRTR-C17.I1) and European Maritime and Fisheries Fund. Publisher Copyright: © 2022 by the authors.A 2D numerical investigation of the power absorption of a constrained wave energy hyperbaric converter (WEHC) under full-scale sea wave conditions is presented. A fully non-linear numerical model DualSPHysics, based on the coupling of a smoothed particle hydrodynamics (SPH) fluid solver with a multibody dynamics solver, is used to model the interaction between wave and WEHC sub-systems. The numerical model was first validated against experimental data for a similar device, with a good accordance between PTO position and velocity. The model is then employed to study the hydrodynamics of a constrained WEHC considering several sea states, different hydraulic power take-off (PTO) damping and breakwater geometries. It is observed that the capture width ratio (CWR) is particularly sensitive to variations in the PTO damping, although the CWR absolute maximum is less sensitive considering mild variations applied to the PTO damping. Both wave height and wave period have an important effect on the CWR. The breakwater geometry is also essential for the performance of the WEHC, with a decrease in maximum CWR of about 15% for porous breakwater. These results are necessary to understand the full-scale behaviour of WEHC.publishersversionpublishe

A survey on Anthozoa and its habitats along the Northwest African coast and some islands: new records, descriptions of new taxa and biogeographical, ecological and taxonomical comments. Part I

Varias especies de Actiniarios y Escleractinias han sido recolectadas y estudiadas a lo largo de la costa noroeste africana y algunos de sus archipiélagos. Esta es la primera parte de un artículo más extenso que está centrado en Marruecos y Cabo Verde pero que también incluye información de otras zonas geográficas (Islas Canarias, Madeira, Gabón y Mauritania). La segunda parte incluirá bastante material del Golfo de Guinea. Cuatro nuevas especies y un nuevo género son descritos además de cinco nuevos registros de especies para la región estudiada. Bellactis caeruleus, Tubastrea caboverdiana, Thalamophyllia wirtzi y Africana wirtzi son las cuatro especies y el nuevo género descrito para la ciencia. Se han completado algunas descripciones de especies que de una forma y otra no estaban bien estudiadas.Several species of Actiniaria and Scleractinia have been searched and collected along the Western African coast and some of its archipelagos. This paper constitutes the first part of an extensive paper and it is focused on Morocco and Cape Verde, although some material and images from other spots (Canary Islands, Madeira, Gabon or even Mauritania) are included. The second part will also include some material from Gulf of Guinea. Four new species and a new genus are described, and five new records are also included in the paper. Bellactis caeruleus, Tubastrea caboverdiana, Thalamophyllia wirtzi and Africana wirtzi are the four new species and the new genus described. Some species, due to previous lack of good descriptions, are presented more deeply from the point of view of the descriptive aspect

Sliding blocks with random friction and absorbing random walks

With the purpose of explaining recent experimental findings, we study the distribution $A(\lambda)$ of distances $\lambda$ traversed by a block that slides on an inclined plane and stops due to friction. A simple model in which the friction coefficient $\mu$ is a random function of position is considered. The problem of finding $A(\lambda)$ is equivalent to a First-Passage-Time problem for a one-dimensional random walk with nonzero drift, whose exact solution is well-known. From the exact solution of this problem we conclude that: a) for inclination angles $\theta$ less than \theta_c=\tan(\av{\mu}) the average traversed distance \av{\lambda} is finite, and diverges when $\theta \to \theta_c^{-}$ as \av{\lambda} \sim (\theta_c-\theta)^{-1}; b) at the critical angle a power-law distribution of slidings is obtained: $A(\lambda) \sim \lambda^{-3/2}$. Our analytical results are confirmed by numerical simulation, and are in partial agreement with the reported experimental results. We discuss the possible reasons for the remaining discrepancies.Comment: 8 pages, 8 figures, submitted to Phys. Rev.

The significance of using satellite imagery data only in Ecological Niche Modelling of Iberian herps

The environmental data used to calculate ecological niche models (ENM) are obtained mainly from ground-based maps (e.g., climatic interpolated surfaces). These data are often not available for less developed areas, or may be at an inappropriate scale, and thus to obtain this information requires fieldwork. An alternative source of eco-geographical data comes from satellite imagery. Three sets of ENM were calculated exclusively with variables obtained (1) from optical and radar images only and (2) from climatic and altitude maps obtained by ground-based methods. These models were compared to evaluate whether satellite imagery can accurately generate ENM. These comparisons must be made in areas with well-known species distribution and with available satellite imagery and ground-based data. Thus, the study area was the south-western part of Salamanca (Spain), using amphibian and reptiles as species models. Models' discrimination capacity was measured with ROC plots. Models' covariation was measured with a Spatial Spearman correlation. Four modelling techniques were used (Bioclim, Mahalanobis distance, GARP and Maxent). The results of this comparison showed that there were no significant differences between models generated using remotely sensed imagery or ground-based data. However, the models built with satellite imagery data exhibited a larger diversity of values, probably related to the higher spatial resolution of the satellite imagery. Satellite imagery can produce accurate ENM, independently of the modelling technique or the dataset used. Therefore, biogeographical analysis of species distribution in remote areas can be accurately developed only with variables from satellite imagery

UPLC-MS-ESI-QTOF analysis and antifungal activity of the spondias tuberosa arruda leaf and root hydroalcoholic extracts

The aim of this study was to identify and evaluate the chemical compositions and effects of the S. tuberosa leaf and root hydroalcoholic extracts (HELST and HERST) against different strains of Candida. Chemical analysis was performed by Ultra-Performance Liquid Chromatography Coupled to Quadrupole/Time of Flight System (UPLC-MS-ESI-QTOF). The Inhibitory Concentration of 50% of the growth (IC50) as well as the intrinsic and combined action of the extracts with the antifungal fluconazole (FCZ) were determined by the microdilution method while the minimum fungicidal concentrations (MFCs) and the effect on fungal morphological transitions were analyzed by subculture and in humid chambers, respectively. From the preliminary phytochemical analysis, the phenols and flavonoids were the most abundant. The intrinsic IC50 values for HELST ranged from 5716.3 to 7805.8 \ub5g/mL and from 6175.4 to 51070.9 \ub5g/mL for the HERST, whereas the combination of the extracts with fluconazole presented IC50 values from 2.65 to 278.41 \ub5g/mL. The MFC of the extracts, individually, for all the tested strains was 6516384 \ub5g/mL. When fluconazole was combined with each extract, the MFC against CA URM 5974 was reduced (HELST: 2048 and HERST: 4096 \ub5g/mL). Synergism was observed against standard C. albicans (CA) and C. tropicalis (CT) strains and with the root extract against the CT isolate. The leaf extract inhibited the morphological transition of all strains while the root extract inhibited only CT strains