idUS. Depósito de Investigación Universidad de Sevilla
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New insights about the effect of cosolvent on the plasmon of gold nanoparticles of different sizes
No full textA comprehensive study has been carried out on the effect caused on the localized surface plasmon resonance of gold nanoparticles (AuNPs) of different sizes by cosolvents formed by tetrahedral alcohols. Specifically, methanol, ethanol, 2-propanol and tert-butanol at different molar fractions and AuNPs of 5, 15 and 30 nm synthesized following a variant of the Turkevich chemical reduction method and characterized by electron microscopy and spectrophotometry techniques have been used. By applying Mie theory, theoretical absorption spectra have been obtained showing almost a null effect on the plasmon position after the addition of the cosolvent due to changes in the dielectric constant of the medium, exposing the importance of the structure of the medium, since, by increasing the hydrophobicity of the alcohol, a greater aggregation effect on the AuNPs has been found, which is also highlighted by increasing their size. The importance of future research is highlighted to understand the aggregation mechanism found, which could be the result of alcohol-alcohol, alcohol-stabilizer, or alcohol-metal surface interactions
Al margen de la norma. Manifestaciones y representaciones siniestras de lo femenino en el Próximo Oriente antiguo
No full textDesde mediados del siglo XX, el interés por la aplicación de la perspectiva de género ha permitido un acercamiento crítico a las representaciones femeninas y el lugar que ocupan en los textos y el arte del Próximo Oriente antiguo. Siguiendo esta línea de estudio, este libro recoge una serie de aportaciones sobre las representaciones de la mujer en los mundos egipcios, mesopotámico, bíblico y persa, alejadas de los modelos habituales de hija, esposa o madre. Para ello, los autores de cada uno de los capítulos se han acercado a las figuras ominosas de las otras mujeres, presentando aspectos sobre la maternidad, la sexualidad o las corporalidades femeninas. El objetivo es volver la mirada a esos rostros que se convirtieron en una amenaza o un recordatorio del orden impuesto por las jerarquías de género
Association of Physical Exercise With Structural Brain Changes and Cognitive Decline in Patients With Early Parkinson Disease
No full textBackground and Objectives
Accumulating evidence suggests that physical activity is associated with a better clinical and cognitive course in Parkinson disease (PD), yet whether these effects are subserved by structural brain alterations are largely unexplored. The aim of this study was to investigate whether regular physical activity associates with a reduced longitudinal rate of neurodegeneration and slower cognitive decline in PD.
Methods
In this longitudinal, observational cohort study, we used data from the Parkinson's Progression Markers Initiative. We included patients with early PD who had serial assessments of regular physical activity, measured using the Physical Activity Scale for the Elderly, along with serial MRI scans from at least 2 time points over 4 years of follow-up. Regional cortical thickness and subcortical volumes were calculated using established procedures. We used multivariate linear mixed-effects models to analyze the effect of regular physical activity on the progression of MRI parameters over time. We further used mediation models with nonparametric bootstrap to test mediation effects of longitudinal structural brain changes on the association between regular physical activity and longitudinal cognitive functioning.
Results
A total of 120 patients with early PD were included (mean [SD] age = 60.8 [9.3] years; 33% women). Average regular physical activity levels over time were significantly associated with slower cortical thinning in temporoparietal cortical regions, including the lateral temporal cortex, the fusiform gyrus, the parahippocampal gyrus, and the inferior parietal cortex (p < 0.05). Regular physical activity levels over time were also associated with slower volume loss in the hippocampus and the amygdala (p < 0.05). The association of regular physical activity with slower decline in memory and attention functions was mediated by slower decreases in temporoparietal cortical thickness (βPASE-HVLT, = 0.06, p = 0.050; βPASE-SDMT = 0.04, p = 0.017) and hippocampal volume (βPASE-SDMT = 0.03, p = 0.016).
Discussion
Regular physical activity is associated with a slower rate of neurodegeneration in the temporoparietal cortex and limbic areas in PD, which contributes to preserved cognitive function and improved long-term outcomes. This supports regular physical activity as a key intervention to delay disease progression and improve quality of life in patients with PD
In vitro toxicity of two functionalized reduced graphene oxide materials with potential application in food packaging
No full textFunctionalized graphene materials have been proposed as nanofillers in food packaging applications as they improve the characteristics of the resulting nanocomposites. But food contact materials require a toxicity evaluation previous their authorization and use. In this sense, reduced graphene oxide functionalized with dodecyl amine (DA-rGO), and [2-(methacryloyloxy) ethyl] trimethylammonium chloride (MTAC-rGO) were characterized and their internalization and cytotoxicity in Caco-2 and HepG2 cultures evaluated. Cell viability decreased from 100 μg/mL in all experimental trials, and oxidative stress by means of a reduction in glutathione levels was evidenced as one of the potential toxicity mechanisms involved. Moreover, both materials were subjected to an in vitro digestion process to investigate their potential changes along the gastrointestinal tract. Digested samples were characterized, and the cytotoxicity also evaluated showing an exacerbation. These results raise concerns about the impact of these materials after oral exposure, and therefore further research is necessary
Responsables de las infracciones administrativas
No full textCometida una infracción administrativa, ¿a quién hay que sancionar?: ¿a la empresa por lo que ha hecho su empleado?, ¿al propietario del bien en el que o con el que se ha cometido?, ¿a las administraciones que incurren en ella?, ¿a los administradores de las personas jurídicas?; y, si las personas jurídicas se extinguen, ¿a quién se puede sancionar? A preguntas similares a las anteriores se da respuesta en esta obra con un análisis de cientos de sentencias y leyes. Se hace atendiendo especialmente al principio de responsabilidad personal, que se proclama siempre, pero que con frecuencia se ve erosionado hasta hacerlo casi irrelevante. Frente a ello, en el volumen ese principio se reafirma y se combaten las desviaciones que son admitidas sin justificación suficiente
Asymptotic analysis of the Navier-Stokes equations in a thin domain with power law slip boundary conditions
No full textThis theoretical study deals with the Navier-Stokes equations posed in a 3D thin domain with thickness 0 γs∗ corresponds to a limit boundary condition of type perfect slip. The subcritical case γ < γs∗ corresponds to a limit boundary condition of type no-slip
The effectiveness of pharmaceutical tenders as a cost containment mechanism: analysis through the Synthetic Control Method. The case of Andalusia (Spain)
No full textBackground: Outpatient pharmaceutical tenders are not a widespread measure. In Spain, the sub-central gov-
ernment of the Andalusian region is the only Spanish health administration to have applied them.
Objective: This work aims to evaluate the effectiveness of this measure in reducing public pharmaceutical
expenditure during the period it was in force –from June 2012 to December 2020.
Methods: We use the Synthetic Control Method (SCM), which estimates a counterfactual (synthetic) value for our
variable of interest (outpatient pharmaceutical expenditure per capita) based on a set of predictor variables from
a combination of units from the potential control group (in this case, the rest of the regions in Spain).
Results: The results of the SCM show no evidence that the pharmaceutical tender implemented in Andalusia
reduced pharmaceutical spending. Statistical tests show that the null hypothesis of no differential effect of the
measure on pharmaceutical spending during the period in which it was in force cannot be rejected. These results
are robust to various robustness tests.
Conclusions: Public tenders for outpatient pharmaceuticals in Andalusia did not prove effective as a mechanism
for controlling public expenditure during the period it was in force and failed to lead to a reduction in expen-
diture when compared to the rest of the regions in Spain, which did not apply it
Bayesian semi-parametric approaches to normal/independent and elliptical distributions
No full textThis article introduces a novel, Bayesian, semi-parametric approach to inference for both elliptical and normal/independent distributions. The location and scale parameters are modelled parametrically and a suitable transformation of the modular variable is modelled using Dirichlet process mixtures. A feature of our approach is that the partial lack of identifiability inherent in both elliptical and normal/independent distributions can be accounted for by incorporating a restriction on the diagonal elements of the scale matrix. Posterior computation is carried out using a Markov chain Monte Carlo algorithm.A novel technique for model selection, based on an approximation of the deviation information criterion, is introduced. As shown by a numerical study based on simulation, the approach can be used to discriminate between elliptical, and normal/independent distributions. Finally, our methodology is illustrated with both simulated and real data
Workplace-based physiotherapy of elderly-care workers with non-specific chronic neck pain: a randomized controlled trial
No full textObjective: To analyze the clinical efficacy of a multimodal physical therapy program combined with pain neuroscience education (PNE) in elderly care workers with non-specific chronic neck pain (NSCNP).
Methods: A sample of 50 elderly care workers was randomly assigned to an Intervention Group (IG; n = 25), which received a multimodal physiotherapy program combined with PNE, and a Control Group (IG; n = 25). Self-reported pain intensity (VAS), pressure pain threshold (PPT), cervical disability (CDU), active cervical range of motion (CRoM), and health-related quality of life (HRQL), were analyzed.
Results: Significant results were observed for IG in the variables analyzed p < 0.001. Improvements were maintained with large effect sizes (d ≥ 0.9) after a 4-week follow up.
Conclusion: Five weeks of workplace-based physiotherapy combined with PNE reduced self-reported pain intensity and increase PPT and CRoM in caregivers with NSCNP
A Delay Nonlocal Quasilinear Chafee–Infante Problem: An Approach via Semigroup Theory
No full textIn this work we study a dissipative one dimensional scalar parabolic problem with non-local nonlinear diffusion with delay. We consider the general situation in which the functions involved are only continuous and solutions may not be unique. We establish conditions for global existence and prove the existence of global attractors. All results are presented only in the autonomous since the non-autonomous case follows in the same way, including the existence of pullback attractors. A particularly interesting feature is that there is a semilinear problem (nonlocal in space and in time) from which one can obtain all solutions of the associated quasilinear problem and that for this semilinear problem the delay depends on the initial function making its study more involved