942 research outputs found

    Pattern of degeneration of the rat inferior olivary complex after the early postnatal axotomy of the olivocerebellar projection

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    Neuronal death of inferior olivary neurons after early axotomy of the olivocerebellar tract was studied in newborn (Pl) hemicerebellectomized rats during the first six days after lesion. The degeneration of the inferior olive showed a topographic pattem from one (P2) to six days after axotomy (P7), after which this complex had almost completely disappeared. The first degenerative changes were observed in the principal olive (P2), while the media1 accessory olive was the later-degenerated area (P5). The analysis of these degenerative changes provides a reference for future experimental studies. Furthermore, the topographic study of the degenerative process demonstrated that: i) the most vulnerable neurons were dorsolaterally located, whereas the most resistant ones occupied the media1 aspect of the inferior olivary complex, ii) the comparison between the topographical arrangement of the inferior olivary neurons according to their birth dates, and the rate of degenerative changes observed after hemicerebellectomy, open the possibility that the neurona1 generation date and the response to the axotomy of the inferior olivary neurons could be related

    Social Services in Times of Economic and Social Crisis: The case of Spain

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    The financial and economic crisis which originated in 2008 has had a severe impact on the population of the Southern European countries. The economic policies of austerity and public deficit control, as well as the neo-liberal and conservative social policies are redefining the public social protection systems, in particular the Social Services. In order to get to understand the current situation, we shall explain how the Social Services were developed in Spain and analyse the causes and consequences of the economic crisis. The working hypothesis is that the greater the increase on the population’s needs, the more developed the Social Services should be. We carried out a descriptive analysis of the situation as far as the social impacts of the crisis per region are concerned. We tested the hypothesis through a parametric model of analysis of variance (one-way ANOVA) triangulating with the non-parametric Kruscal-Wallis test. The working hypothesis failed. The regions with better developed Social Services show a lower level of poverty and social exclusion. The challenges that the public Social Services system faces in times of crisis is three-fold: 1) re-modelling of local administration and transferring of the municipal Social Services responsibilities to the regional administration; 2) an increase of the population at risk of poverty and social exclusion 3) impact on social policies.The research leading to these results has received funding from the European Union Seventh Framework Programme FP7-PEOPLE-2012-IRSES under grant agreement No 318938

    Influence of conical projectile diameter on perpendicular impact oh thin steel plate

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    A numerical study of conical projectiles for perpendicular impact on a thin steel plate is reported. The target material considered, Weldox 460 E steel, is frequently used for this kind of application and several results of experiments are available in the international literature to verify numerical simulations. The Johnson-Cook constitutive relation coupled with the Johnson-Cook failure criterion have been applied to analyse penetration of the target and also the failure process. The analysis has been focussed on the influence of the projectile diameter on the perforation process, assuming the same projectile mass. The aim was to preserve the same initial kinetic energy and identical nose angle. The goal is to estimate the ballistic limit, the residual velocity, the plastic work, and the temperature levels produced during the penetration process. The analysis has shown a linear increase of the ballistic limit with the projectile diameter.Publicad

    Stellar populations of galaxies in the ALHAMBRA survey up to z1z \sim 1. II. Stellar content of quiescent galaxies within the dust-corrected stellar mass-colour and the UVJUVJ colour-colour diagrams

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    Our aim is to determine the distribution of stellar population parameters (extinction, age, metallicity, and star formation rate) of quiescent galaxies within the rest-frame stellar mass-colour and UVJUVJ colour-colour diagrams corrected for extinction up to z1z\sim1. These novel diagrams reduce the contamination in samples of quiescent galaxies owing to dust-reddened galaxies, and they provide useful constraints on stellar population parameters. We set constraints on the stellar population parameters of quiescent galaxies combining the ALHAMBRA multi-filter photo-spectra with our SED-fitting code MUFFIT, making use of composite stellar population models. The extinction obtained by MUFFIT allowed us to remove dusty star-forming (DSF) galaxies from the sample of red UVJUVJ galaxies. The distributions of stellar population parameters across these rest-frame diagrams are revealed after the dust correction and are fitted by the LOESS method to reduce uncertainty effects. Quiescent galaxy samples defined via classical UVJUVJ diagrams are typically contaminated by a 20\sim20% fraction of DSF galaxies. A significant part of the galaxies in the green valley are actually obscured star-forming galaxies (3065\sim30-65%). Consequently, the transition of galaxies from the blue cloud to the red sequence, and hence the related mechanisms for quenching, seems to be much more efficient and faster than previously reported. The rest-frame stellar mass-colour and UVJUVJ colour-colour diagrams are useful for constraining the age, metallicity, extinction, and star formation rate of quiescent galaxies by only their redshift, rest-frame colours, and/or stellar mass. Dust correction plays an important role in understanding how quiescent galaxies are distributed in these diagrams and is key to performing a pure selection of quiescent galaxies via intrinsic colours.Comment: (37 pages, 29 figures, accepted for publication in A&A

    Formulation and optimization of polymeric nanoparticles loaded with riolozatrione: a promising nanoformulation with potential anti-herpetic activity

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    Riolozatrione (RZ) is a diterpenoid compound isolated from a dichloromethane extract of the Jatropha dioica root. This compound has been shown to possess moderate anti-herpetic activity in vitro. However, because of the poor solubility of this compound in aqueous vehicles, generating a stable formulation for potential use in the treatment of infection is challenging. The aim of this work was to optimize and physiochemically characterize Eudragit® L100-55-based polymeric nanoparticles (NPs) loaded with RZ (NPR) for in vitro anti-herpetic application. The NPs formulation was initially optimized using the dichloromethane extract of J. dioica, the major component of which was RZ. The optimized NPR formulation was stable, with a size of 263 nm, polydispersity index < 0.2, the zeta potential of –37 mV, and RZ encapsulation efficiency of 89 %. The NPR showed sustained release of RZ for 48 h with release percentages of 95 and 97 % at neutral and slightly acidic pH, respectively. Regarding in vitro anti-herpetic activity, the optimized NPR showed a selectivity index for HSV-1 of ≈16 and for HSV-2 of 13

    Classical and semi-classical energy conditions

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    The standard energy conditions of classical general relativity are (mostly) linear in the stress-energy tensor, and have clear physical interpretations in terms of geodesic focussing, but suffer the significant drawback that they are often violated by semi-classical quantum effects. In contrast, it is possible to develop non-standard energy conditions that are intrinsically non-linear in the stress-energy tensor, and which exhibit much better well-controlled behaviour when semi-classical quantum effects are introduced, at the cost of a less direct applicability to geodesic focussing. In this article we will first review the standard energy conditions and their various limitations. (Including the connection to the Hawking--Ellis type I, II, III, and IV classification of stress-energy tensors). We shall then turn to the averaged, nonlinear, and semi-classical energy conditions, and see how much can be done once semi-classical quantum effects are included.Comment: V1: 25 pages. Draft chapter, on which the related chapter of the book "Wormholes, Warp Drives and Energy Conditions" (to be published by Springer), will be based. V2: typos fixed. V3: small typo fixe

    J-PLUS: A wide-field multi-band study of the M15 globular cluster. Evidence of multiple stellar populations in the RGB

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    The Javalambre Photometric Local Universe Survey (J-PLUS) provides wide field-of-view images in 12 narrow, intermediate and broad-band filters optimized for stellar photometry. Here we have applied J-PLUS data for the first time for the study of Galactic GCs using science verification data obtained for the very metal-poor GC M\,15. Our J-PLUS data provide low-resolution spectral energy distributions covering the near-UV to the near-IR, allowing us to search for MPs based on pseudo-spectral fitting diagnostics. J-PLUS CMDs are found to be particularly useful to search for splits in the sequences formed by the upper red giant branch (RGB) and asymptotic giant branch (AGB) stars. We interpret these split sequences as evidence for the presence of MPs. This demonstrates that the J-PLUS survey will have sufficient spatial coverage and spectral resolution to perform a large statistical study of GCs through multi-band photometry in the coming years.Comment: 11 pages, 11 figures. Accepted for publication @ A&

    Increasing the quantum efficiency of InAs/GaAs QD arrays for solar cells grown by MOVPE without using strain-balance technology

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    Research into the formation of InAs quantum dots (QDs) in GaAs using the metalorganic vapor phase epitaxy technique ispresented. This technique is deemed to be cheaper than the more often used and studied molecular beam epitaxy. The bestconditions for obtaining a high photoluminescence response, indicating a good material quality, have been found among awide range of possibilities. Solar cells with an excellent quantum ef?ciency have been obtained, with a sub-bandgapphoto-response of 0.07 mA/cm2per QD layer, the highest achieved so far with the InAs/GaAs system, proving the potentialof this technology to be able to increase the ef?ciency of lattice-matched multi-junction solar cells and contributing to abetter understanding of QD technology toward the achievement of practical intermediate-band solar cells

    Self-reported daily walking time in COPD: relationship with relevant clinical and functional characteristics

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    Background: Quantifying physical activity in chronic obstructive pulmonary disease (COPD) is important as physical inactivity is related to poor health outcomes. This study analyzed the relationship between patients' self-reported daily walking time and relevant characteristics related to COPD severity. Methods: Pooled analysis was performed on data from four observational studies on which daily walking time was gathered from a personal interview. Patients were classified as physically inactive if walking time was 3, post-bronchodilator forced expiratory volume in the first second 4, and CAT score >30. Conclusion: Lower self-reported walking times are related to worse markers of disease severity in COPD
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