Felix Scholarship

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En Espana el voleibol es uno de los deportes cuyos origenes ha sido menos estudiado. Este articulo aporta datos ineditos sobre los antecedentes del voleibol en Espana durante el periodo de 1920 a 1938, en el contexto escolar, militar y civil. El objeto de estudio se centra en averiguar el porque su practica no fue aceptada, asi como sucedio en otros deportes colectivos. Una metodologia sustentada en el analisis documental de fuentes primarias descubre que el voleibol fue un deporte considerado poco viril, es decir, no alcanzaba el ideal de endurecimiento que mostraban otros deportes, en los que el combate directo (cuerpo a cuerpo) con el adversario proporcionaba mayores rasgos de masculinizacion, con lo cual no satisfacia los intereses regeneracionistas del momento

In this work we report on the experimental and theoretical investigations of the progressional complexation of the polycyclic aromatic hydrocarbon (PAH) acenaphthene with itself and with water. In the interstellar medium, PAH complexes are an important link between molecular gas and solid state configurations of carbon, and in the form of grains they are postulated to serve as chemical catalysts. However, no direct detection of PAHs or their (microhydrated) complexes in interstellar space has been achieved as of yet. Therefore, we provide UV and far-infrared ion dip spectra of homogeneous PAH multimers and their hydrated clusters. The far-IR region of the IR spectrum is especially interesting since it contains the most spectral features that arise due to complexation or microhydration. We present microhydrated PAH complexes up to the third order, where we show that the water clusters are locked with little perturbation on the different PAH platforms. Density functional theory (DFT) calculations involving hydrogen bond interactions still seem challenging for predicting the far-IR frequency range, although applying anharmonic corrections leads to slight improvements.

Introduction: Symptomatic internal carotid artery occlusion (ICAO) can lead to subsequent neurologic decline, recurrent stroke, and mortality. We sought to evaluate safety and feasibility of endovascular revascularization for ICAO without tandem intracranial large vessel occlusion (LVO). Methods: This is a retrospective cohort analysis of all patients presenting to a single academic center with ischemic stroke and ipsilateral, cervical ICAO from November 2003 through April 2016. Patients were excluded if pre-procedural angiography demonstrated tandem LVO or if patients were known to have chronic ICAO. Study endpoints included discharge neurologic exam, post-procedural infarct burden, 3-month functional outcomes, and treatment durability. Results: A total of 107 patients with symptomatic, angiographically confirmed cervical ICAO without tandem LVO were identified. Median admission NIHSS was 8 (IQR 11). Baseline radiographic stroke severity was assessed by ASPECT score (median 9; IQR 2), perfusion mismatch (present in 93%), and clinical-diffusion mismatch (42%). Median time from symptom onset to treatment was 25 hours (IQR 61). Successful revascularization was achieved in 92% of patients. At discharge, 83% had stable or improved NIHSS, while at 3-months 65% achieved functional independence (mRS ≤2). The most common complication was distal embolization (22%) of which 16% required intra-arterial treatment. Rate of significant restenosis (≥70%) was 15% at 1-year. Conclusions: Stenting in selected patients at risk of neurological deterioration due to symptomatic ICAO can be performed with high rates of technical success and good clinical outcomes. Because of significant peri-procedural risks and high rates of restenosis, randomized studies are necessary to understand the benefit of this approach.

Proton bonding drives the supramolecular chemistry of a broad range of materials with polar moieties. Proton delocalization and electronic charge redistribution have a profound impact on the structure of proton-bound molecular frameworks, and pose fundamental challenges to quantum chemical modelling. This study provides insights into the structural and spectral signatures of the intramolecular proton bond formed in a benchmark polyazamacrocycle anionophore (cyclen, 1,4,7,10-tetraazacyclododecane). Infrared action spectroscopy is employed to characterize the macrocycle, isolated in protonated form. In its most stable configuration, protonated cyclen adopts an open arrangement of Cs symmetry with a particularly strong NHδ+N bond across the cavity. The quantum chemical analysis of the infrared spectrum reveals intrinsic difficulties for the accurate description of the vibrational modes of the system. The reconciliation of the computational predictions with experiment demands a careful anharmonic treatment of the proton motion, which exposes the limitations of current methods. Best results are obtained with the incorporation of anharmonicity only to the fundamental modes directly related to motions of the proton. However, the full anharmonic treatment of the system fails to describe correctly the vibrations related to the macrocycle backbone. The results should serve as motivation for new developments in the modelling of proton bonded systems.

Abstract In this contribution the modelling of electromechanical interactions in electrical machines is revised and analysed. Based on Lagrange's equations of the second kind, approaches from literature are classified concerning the coupling between mechanical motion and electrical system behaviour. It is shown, that the modelling has a significant influence on the assessment of oscillations. This circumstance is shown investigating self‐excited oscillations in a 2‐pole asynchronous machine. (© 2017 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)

The hip-joint capsule is exposed to increased tension forces during canine hip dysplasia, resulting in inflammation of the capsular tissue. It has been postulated that inflammation is associated with an increased nerve-distribution density. Therefore, it could be supposed that the nerve-distribution density in the hip-joint capsule is higher in dogs with dysplastic hip compared to healthy dogs. In 16 Labrador Retriever dogs that had been euthanised due to unrelated reasons, the hip joints were classified as normoplastic (group 1, n=18) or dysplastic (group 2, n=14) based on radiography. Following staining of the capsular nerve fibres by the Sihler method, histological specimens of the hip-joint capsules were scanned. By subdividing each specimen into 10 quadrants numbered from dorsomedial (Q01) to craniodorsolateral (Q10), the ratio of black to white pixels was calculated digitally for each specimen and each quadrant by using a semiautomatic image analysis. Statistical analysis was performed using an independent t-test. Comparison of the mean values of each quadrant showed a significantly higher (p<0.03) nerve distribution density for the craniodorsolateral quadrant (Q10) in group 2 when compared to group 1. Mean nerve-distribution density for all quadrants combined was not significantly different between the two groups. The increase in nerve-distribution density of the craniodorsal region of the hip-joint capsule in dogs with dysplastic hip could be the result of increased tension forces on this area following hip-joint dysplasia. The craniodorsal region of the hip-joint capsule is an important origin of pain and coxarthrosis in canine hip dysplasia. The results provide the pathophysiological basis for the efficacy of hip-joint denervation. Denervation of the cranial region of the acetabular rim is essential to reduce capsular inflammation and joint-related pain in canine hip dysplasia.

The fundamental origins surrounding the dynamics of disordered solids near their characteristic glass transitions continue to be fiercely debated, even though a vast number of materials can form amorphous solids, including small-molecule organic, inorganic, covalent, metallic, and even large biological systems. The glass-transition temperature, Tg, can be readily detected by a diverse set of techniques, but given that these measurement modalities probe vastly different processes, there has been significant debate regarding the question of why Tg can be detected across all of them. Here we show clear experimental and computational evidence in support of a theory that proposes that the shape and structure of the potential-energy surface (PES) is the fundamental factor underlying the glass-transition processes, regardless of the frequency that experimental methods probe. Whilst this has been proposed previously, we demonstrate, using ab initio molecular-dynamics (AIMD) simulations, that it is of critical importance to carefully consider the complete PES - both the intra-molecular and inter-molecular features - in order to fully understand the entire range of atomic-dynamical processes in disordered solids. Finally, we show that it is possible to utilise this dependence to directly manipulate and harness amorphous dynamics in order to control the behaviour of such solids by using high-powered terahertz pulses to induce crystallisation and preferential crystal-polymorph growth in glasses. Combined, these findings provide compelling evidence that the PES landscape, and the corresponding energy barriers, are the ultimate controlling feature behind the atomic and molecular dynamics of disordered solids, regardless of the frequency at which they occur.

Saligenin (2-(hydroxymethyl)phenol) exhibits both strong and weak intramolecular electrostatic interactions. The bonds that result from these interactions compete with intermolecular hydrogen bonds once saligenin binds to one or more water molecules. Infrared (IR) ultraviolet (UV) ion-dip spectroscopy was used to study isolated saligenin-(H2O)n clusters (n = 1-3) in the far- and mid-IR regions of the spectrum. Both harmonic and anharmonic (coupled local modes and Born-Oppenheimer molecular dynamics) quantum chemical calculations were applied to assign cluster geometries to the measured spectra, and to assign vibrational modes to all spectral features measured for each cluster. The hydrated clusters with n = 1 and 2 have geometries that are quite similar to benzyl alcohol-water clusters, whereas the larger clusters with n = 3 show structures equivalent to the isolated water pentamer. Systematic shifts in the frequencies of three hydrogen bond (H-bond) deforming modes, namely OH stretching, OH torsion and H-bond stretching, were studied as a function of the hydrogen bond strength represented by either the OH bond length or the H-bond length. The shifts of the frequencies of these three modes correlate linearly to the OH length, despite both intra- and intermolecular H-bonds being included in this analysis. The OH torsion vibration displays the largest frequency shift when H-bonded, followed by the OH stretching vibrations and finally the H-bond stretching frequency. The frequency shifts of these H-bond deforming modes behave non-linearly as a function of the H-bond length, asymptotically approaching the frequency expected for the non H-bonded modes. The nonlinear behavior was quantified using exponential functions.