2,393 research outputs found
Disrupted functional brain network organization in patients with obstructive sleep apnea.
IntroductionObstructive sleep apnea (OSA) subjects show impaired autonomic, affective, executive, sensorimotor, and cognitive functions. Brain injury in OSA subjects appears in multiple sites regulating these functions, but the integrity of functional networks within the regulatory sites remains unclear. Our aim was to examine the functional interactions and the complex network organization of these interactions across the whole brain in OSA, using regional functional connectivity (FC) and brain network topological properties.MethodsWe collected resting-state functional magnetic resonance imaging (MRI) data, using a 3.0-Tesla MRI scanner, from 69 newly diagnosed, treatment-naïve, moderate-to-severe OSA (age, 48.3 ± 9.2 years; body mass index, 31 ± 6.2 kg/m(2); apnea-hypopnea index (AHI), 35.6 ± 23.3 events/h) and 82 control subjects (47.6 ± 9.1 years; body mass index, 25.1 ± 3.5 kg/m(2)). Data were analyzed to examine FC in OSA over controls as interregional correlations and brain network topological properties.ResultsObstructive sleep apnea subjects showed significantly altered FC in the cerebellar, frontal, parietal, temporal, occipital, limbic, and basal ganglia regions (FDR, P < 0.05). Entire functional brain networks in OSA subjects showed significantly less efficient integration, and their regional topological properties of functional integration and specialization characteristics also showed declined trends in areas showing altered FC, an outcome which would interfere with brain network organization (P < 0.05; 10,000 permutations). Brain sites with abnormal topological properties in OSA showed significant relationships with AHI scores.ConclusionsOur findings suggest that the dysfunction extends to resting conditions, and the altered FC and impaired network organization may underlie the impaired responses in autonomic, cognitive, and sensorimotor functions. The outcomes likely result from the prominent structural changes in both axons and nuclear structures, which occur in the condition
El contrato de hechura de un Nazareno de Bernabé de Gaviria para Motril
Bemabé de Gaviria is a key figure in the Granada artistic world, since he consolidated the style first established by Pablo de Rojas at the end of the 16th century. The commission for a Nazarene given by the town of Motril (Granada) is unusual, and offers an example of the importance of this artist at the beginning of the 17th century. The work, whose present whereabouts is unfortunately unknown, conforms to the stipulations of the Council of Trent and falls in with the tastes and the ' needs' of the epoch.La figura de Bernabé de Gaviria dentro del panorama artístico granadino podemos definirla como clave ya que se nos muestra como un artista que consolida los modelos propuestos, principalmente _por su maestro Pablo de Rojas, a finales del s. XVI. El contrato del Nazareno para la localidad granadina de Motril, aparte de novedoso, es ejemplo claro de la importancia que adquiere nuestro artista a comienzos del Setecientos. La imagen, de la que por desgracia no tenemos noticia de su paradero, se ajusta perfectamente a lo dictado en Trento, respondiendo a los gustos y las necesidades de la época
Two-dimensional tunneling in a SQUID
Traditionally quantum tunneling in a static SQUID is studied on the basis of
a classical trajectory in imaginary time under a two-dimensional potential
barrier. The trajectory connects a potential well and an outer region crossing
their borders in perpendicular directions. In contrast to that main-path
mechanism, a wide set of trajectories with components tangent to the border of
the well can constitute an alternative mechanism of multi-path tunneling. The
phenomenon is essentially non-one-dimensional. Continuously distributed paths
under the barrier result in enhancement of tunneling probability. A type of
tunneling mechanism (main-path or multi-path) depends on character of a state
in the potential well prior to tunneling.Comment: 9 pages, 8 figure
Desarrollo y empleo de juegos educativos on-line destinados al auto-entrenamiento y auto-evaluación
La implantación del EEES, está originando cambios
en el modelo docente, cada vez más orientado al trabajo
autónomo del alumno. Los contenidos electrónicos
que apoyan el proceso de aprendizaje también
deben, por tanto, orientarse a facilitar el aprendizaje
autónomo, como por ejemplo los procesos de autoevaluación
y auto-entrenamiento por parte del estudiante.
Por ello, parece adecuado desarrollar contenidos
electrónicos que motiven y a la vez entretengan
de forma amena al alumnado durante su aprendizaje
autónomo. En esta contribución, proponemos
una serie de juegos educativos electrónicos como herramienta
que haga de la auto-evaluación y del autoentrenamiento
un proceso ameno y entretenido.Peer Reviewe
Light-induced instabilities in photo-oriented liquid crystal cells
In a planar liquid crystal sample sandwiched between a photosensitive and a
reference plate instabilities occurred, when the cell was illuminated from the
reference side. The instabilities were induced both by polarized white light
source and monochromatic laser beams. Static and dynamic regimes were found;
for laser irradiation dynamic instability was found only in a range of
polarization directions. A model, developed for monochromatic excitation,
predicts that at certain thicknesses dynamic instability is forbidden.
Experiments on a wedge-like cell confirmed this conclusion.Comment: to appear in Mol. Cryst. Liq. Crys
Surface nanopatterning by ion beam irradiation: compositional effects
Surface nanopatterning induced by ion beam irradiation (IBI) has emerged as an effective nanostructuring technique since it induces patterns on large areas of a wide variety of materials, in short time, and at low cost. Nowadays, two main subfields can be distinguished within IBI nanopatterning depending on the irrelevant or relevant role played by the surface composition. In this review, we give an up-dated account of the progress reached when surface composition plays a relevant role, with a main focus on IBI surface patterning with simultaneous co-deposition of foreign atoms. In addition, we also review the advances in IBI of compound surfaces as well as IBI systems where the ion employed is not a noble gas species. In particular, for the IBI with concurrent metal co-deposition, we detail the chronological evolution of these studies because it helps us to clarify some contradictory early reports. We describe the main patterns obtained with this technique as a function of the foreign atom deposition pathway, also focusing in those systematic studies that have contributed to identify the main mechanisms leading to the surface pattern formation and development. Likewise, we explain the main theoretical models aimed at describing these nanopattern formation processes. Finally, we address two main special features of the patterns induced by this technique, namely, the enhanced pattern ordering and the possibility to produce both morphological and chemical patterns.This work was supported by Ministerio de Economía, Industria y Competitividad (MINECO, Spain), Agencia Estatal de Investigación (AEI, Spain), and Fondo Europeo de Desarrollo Regional (FEDER, EU) through Grant No. PGC2018-094763-B-I00, and by Comunidad de Madrid (Spain) under the Multiannual Agreement with UC3M in the line of Excellence of University Professors, No. EPUC3M23, in the context of the V Plan Regional de Investigación Científica e Innovación Tecnológica (PRICIT), as well as under the TRANSNANOAVANSENS program (S2018-NMT-4349)
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