248 research outputs found
El sonido en la arquitectura religiosa de M. Fisac tras el concilio vaticano II. Propuestas de rehabilitación acústica
Tesis descargada desde TESEOEl presente trabajo de investigación realiza un estudio de las condiciones acústicas actuales de las iglesias construidas por Miguel Fisac, con posterioridad al Concilio Vaticano II. Por la importancia que este evento religioso otorgó a la liturgia de la palabra, la acústica será una constante que Fisac tratará de resolver en su arquitectura eclesial postconciliar. A partir de las condiciones sonoras existentes de todas sus iglesias posteriores al año 1965, y que siguen manteniendo uso cultual, se realizan propuestas de rehabilitación acústica y se valoran las condiciones sonoras previsibles en las mismas.
El trabajo comienza con un recorrido histórico de la iglesia cristiana, desde su origen en tiempos de Jesucristo hasta la segunda mitad del siglo XX, analizando su arquitectura, la relación de ésta con la liturgia y realizando consideraciones generales sobre su acústica. A continuación, se analizan los principales aspectos de la reforma litúrgica del Concilio Vaticano II y su repercusión en el proyecto arquitectónico de las iglesias.
Las consideraciones generales de la arquitectura y la trayectoria profesional de Miguel Fisac constituyen el preámbulo para el estudio de sus intervenciones religiosas, realizadas tanto antes como después del concilio.
Con el objeto de enmarcar en contexto este trabajo de investigación, se presentan algunos de los estudios acústicos más relevantes, realizados en recintos de culto de diversas ciudades europeas y de oriente próximo, destacando la labor científica desarrollada en esta materia, por grupos y proyectos de investigación específicos.
El estudio empírico comienza con la especificación de los objetivos de la investigación y la justificación de la elección de la muestra de estudio (las seis iglesias postconciliares de Fisac en uso actualmente), continuando con la descripción del método del trabajo de investigación, el cual persigue los siguientes propósitos: a) el análisis y valoración sonora actual de cada iglesia, a partir de las mediciones acústicas realizadas in situ; b) elaboración de un modelo informático que reproduzca el campo sonoro actual con suficiente aproximación y fiabilidad; c) realizar propuestas de rehabilitación acústica que mejoren las condiciones sonoras en el interior de cada iglesia, comprobando la idoneidad de las mismas, mediante la simulación acústica del modelo eclesial con las correcciones propuestas; y, d) el análisis y valoración sonora global de la muestra de iglesias.
Finalmente, se aportan una serie de conclusiones acerca del comportamiento acústico de los recintos eclesiales postconciliares de Fisac, tanto en el estado actual como tras las intervenciones propuestas.
Además, más allá del propio ámbito de estudio, la investigación intenta facilitar a los arquitectos y especialistas en la materia, conocimientos y herramientas para la optimización de la calidad acústica de las iglesias, tanto en los proyectos de nueva planta como en las intervenciones de rehabilitación.
Este trabajo de investigación se enmarca dentro de la línea de investigación experimental sobre acústicas de salas, que vienen desarrollando los grupos de investigación de acústica aplicada adscritos al Instituto Universitario de Arquitectura y Ciencias de la Construcción (IUACC) de la Universidad de Sevilla
Factorial structure and psychometric properties of the spanish version of the Pittsburgh sleep quality index in non-professional caregivers
Although sleep issues are among the symptoms commonly experienced by the nonprofessional
caregiver population, and the Pittsburgh Sleep Quality Index (PSQI) is the most widely
used instrument for the assessment of sleep quality, this has not been validated specifically for this
population. The objective of this study was to analyze the factorial structure and psychometric
properties of the Spanish version of the PSQI in a sample of Spanish non-professional caregivers.
Trained clinical psychologists assessed sleep quality using the PSQI, as well as caregiver burden
and psychological distress in 201 non-professional caregivers (87.1% female, Mage = 56.2 years). The
internal consistency of the PSQI was 0.75. The two-factor model (Sleep quality and Disturbances) had
an acceptable fit to the data, was found to be superior to the one-factor model, and more parsimonious
than the three-factor model. There was a significant correlation between the PSQI and caregiver
burden, as well as between the PSQI and psychological distress (p < 0.001 in all cases). A total
score 9 allowed the identification of caregivers with possible anxiety and depression disorders
(sensitivity 70.5%, specificity 71.9%). The results show that the PSQI is a reliable and valid instrument
for the assessment of sleep quality in caregiversThis research was funded by a Spin-off of the University of Santiago de Compostela (Santiago de Compostela, Spain) “Xuntos. Psychological and Psychiatric Care” (2019-CE081-6)S
Microbiota-liver-bile salts axis, a novel mechanism involved in the contrasting effects of sodium selenite and selenium-nanoparticle supplementation on adipose tissue development in adolescent rats
Adolescence is a period during which body composition changes deeply. Selenium (Se)
is an excellent antioxidant trace element related to cell growth and endocrine function. In adolescent rats, low Se supplementation affects adipocyte development differently depending on its
form of administration (selenite or Se nanoparticles (SeNPs). Despite this effect being related to
oxidative, insulin-signaling and autophagy processes, the whole mechanism is not elucidated. The
microbiota–liver–bile salts secretion axis is related to lipid homeostasis and adipose tissue development. Therefore, the colonic microbiota and total bile salts homeostasis were explored in four
experimental groups of male adolescent rats: control, low-sodium selenite supplementation, low
SeNP supplementation and moderate SeNPs supplementation. SeNPs were obtained by reducing
Se tetrachloride in the presence of ascorbic acid. Supplementation was received orally through
water intake; low-Se rats received twice more Se than control animals and moderate-Se rats tenfold
more. Supplementation with low doses of Se clearly affected anaerobic colonic microbiota profile
and bile salts homeostasis. However, these effects were different depending on the Se administration form. Selenite supplementation primarily affected liver by decreasing farnesoid X receptor
hepatic function, leading to the accumulation of hepatic bile salts together to increase in the ratio
Firmicutes/Bacteroidetes and glucagon-like peptide-1 (GLP-1) secretion. In contrast, low SeNP
levels mainly affected microbiota, moving them towards a more prominent Gram-negative profile
in which the relative abundance of Akkermansia and Muribaculaceae was clearly enhanced and the
Firmicutes/Bacteroidetes ratio decreased. This bacterial profile is directly related to lower adipose
tissue mass. Moreover, low SeNP administration did not modify bile salts pool in serum circulation.
In addition, specific gut microbiota was regulated upon administration of low levels of Se in the forms
of selenite or SeNPs, which are properly discussed. On its side, moderate-SeNPs administration led
to great dysbiosis and enhanced the abundance of pathogenic bacteria, being considered toxic. These
results strongly correlate with the deep change in adipose mass previously found in these animals,
indicating that the microbiota–liver–bile salts axis is also mechanistically involved in these changes.Junta de Andalucía y proyectos FEDER Andalucía de la Unión Europea - US-1380878Ministerio de Ciencia, Innovación y Universidades de Epaña - PID2019-109371GB-I00VII Plan Propio de Investigación y Transferencia de la Universidad de Sevilla US 2022 - 2022/00000332 y 2022/0000027
Acceso personalizado a materiales educativos de calidad, creados entre iguales, en una plataforma de aprendizaje en línea
El aprendizaje personalizado, que ahora es posible con ayuda de herramientas tecnológicas, es un tema de gran interés y es aplicado en todos los niveles educativos. Aquí se propone un modelo de aprendizaje que, partiendo de materiales audiovisuales creados por el mismo alumnado bajo unos criterios de calidad establecidos, los organiza y ofrece al alumnado bajo aspectos que requieren atención personalizada. Estos son su nivel de conocimientos, características de su perfil y su ritmo de aprendizaje. Todo ello implementado en una plataforma de aprendizaje como Moodle. Así mismo, la opinión de un grupo de estudiantes, antes y después de la creación de materiales audiovisuales durante un trabajo en equipo, avalan la necesidad de aplicar el modelo propuesto, con una ontología que facilitará tanto la creación, organización y búsqueda de esos materiales, dependiendo de las características del alumnado
New Insights into the Medieval Hispano-Muslim Panel Painting: The Alfarje Found in a Balearic Casal (Spain)
Hispano-Muslim culture flourished during the Middle Ages in the Iberian Peninsula and Balearic Islands. During the restoration of a Balearic nobiliary building (casal), several panels with polychrome decoration on the back side were found. They were part of an old Muslim wooden ceiling (alfarje). A multi-technique strategy including optical microscopy, infrared and μRaman spectroscopies, field emission scanning electron microscopy-X-ray microanalysis (FESEM-EDX), focused ion beam (FIB-FESEM-EDX), atomic force microscopy nanoindentation (AFM-NI), and gas chromatography-mass spectrometry (GC-MS) has been applied in the analysis of these panel paintings and has provided morphological and compositional data that have led to the identification of the materials and artistic technique as well as the alteration mechanisms due to the natural aging and the adverse conditions of conservation. As a novelty, this study has confirmed the use of indigo as a blue pigment, an unusual material in Hispano-Muslim panel painting. Apart from the notable change in the visual appearance observed in the paintings, the study has also confirmed a change in the mechanical resistance in the paint layers. These changes have been induced by the combination of the chemical and microbiological alteration mechanisms identified
Estudio de materiales y técnica de ejecución de los restos de pintura mural romana hallados en una excavación arqueológica de Guadix (Granada)
Este artículo da a conocer unos restos de pintura mural romana encontrados en Guadix, tanto desde el punto de vista arqueológico como analítico. Estos fragmentos de pintura mural constituían parte del material de relleno de una canalización romana, cuya cronología pudo precisarse con exactitud, que posiblemente formaría parte de la red hidráulica de la antigua ACCIS. Ateniéndonos a las características de los fragmentos, se seleccionaron muestras de los colores más frecuentes para determinar los pigmentos utilizados y la técnica de ejecución empleada en su construcción.This article makes Known the remains of Román wall painting found in Guadix, botti fron au archaeological and analytical point of view. These fragments of wall painting constituted part of ttie filling material used in a Román channelling, whose chronology was accurately established, which would probably be part of the hydraulic system in ancient ACCIS. Keeping in mind the characteristics of the fragments, samples of the most frecuent colours were chosen to determine the pigments used and the execution technique employed in its construction
Uraemic toxins impair skeletal muscle regeneration by inhibiting myoblast proliferation, reducing myogenic differentiation, and promoting muscular fibrosis
17 p.Uraemic toxins increase in serum parallel to a decline in the glomerular filtration rate and the development of sarcopenia in patients with chronic kidney disease (CKD). This study analyses the role of uraemic toxins in sarcopenia at different stages of CKD, evaluating changes in the muscular regeneration process. Cultured C2C12 cells were incubated with a combination of indoxyl sulphate and p-cresol at high doses (100 mu g/mL) or low doses (25 mu g/mL and 10 mu g/mL) resembling late or early CKD stages, respectively. Cell proliferation (analysed by scratch assays and flow cytometry) was inhibited only by high doses of uraemic toxins, which inactivated the cdc2-cyclin B complex, inhibiting mitosis and inducing apoptosis (analysed by annexin V staining). By contrast, low doses of uraemic toxins did not affect proliferation, but reduced myogenic differentiation, primed with 2% horse serum, by inhibiting myogenin expression and promoting fibro-adipogenic differentiation. Finally, to assess the in vivo relevance of these results, studies were performed in gastrocnemii from uraemic rats, which showed higher collagen expression and lower myosin heavy chain expression than those from healthy rats. In conclusion, uraemic toxins impair the skeletal muscular regeneration process, even at low concentrations, suggesting that sarcopenia can progress from the early stages of CKD.Instituto de Salud Carlos II
Endothelin-1 induces cellular senescence and fibrosis in cultured myoblasts. A potential mechanism of aging-related sarcopenia
Endothelial dysfunction, with increased endothelin-1 (ET-1) synthesis, and sarcopenia, characterized by the loss of muscular mass and strength, are two aging-related conditions. However, a relationship between them has not been already established. The aim of this study was to determine whether ET-1 induces senescence and fibrosis in cultured murine myoblasts, which could be involved in the development of sarcopenia related to aging. For this purpose, myoblasts were incubated with ET-1 to assess cellular senescence, analyzed by senescence associated beta-galactosidase activity and p16 expression; and fibrosis, assessed by fibronectin expression. ET-1 induced myoblast senescence and fibrosis through ETA receptor. The use of antioxidants and several antagonists revealed that ET-1 effect on senescence and fibrosis depended on ROS production and activation of PI3K-AKT-GSK pathway. To stress the in vivo relevance of these results, circulating ET-1, muscular strength, muscular fibrosis and p16 expression were measured in male C57Bl6 mice from 5-18-24-months-old. Old mice shown high levels of ET-1 correlated with muscular fibrosis, muscular p16 expression and loss of muscle strength. In conclusion, ET-1 promotes fibrosis and senescence in cultured myoblasts, similar results were found in old mice, suggesting a potential role for ET-1 in the development of sarcopenia related to aging
Aging-related hyperphosphatemia impairs myogenic differentiation and enhances fibrosis in skeletal muscle
14 p.Background Hyperphosphatemia has been related to the development of sarcopenia in aging mice. We describe the
intracellular mechanisms involved in the impairment of the myogenic differentiation promoted by hyperphosphatemia
and analyse these mechanisms in the muscle from older mice.
Methods C2C12 cells were grown in 2% horse serum in order to promote myogenic differentiation, in the presence or
absence of 10 mM beta-glycerophosphate (BGP) for 7 days. Troponin T, paired box 7 (Pax-7), myogenic factor 5 (Myf5),
myogenic differentiation 1 (MyoD), myogenin (MyoG), myocyte enhancer factor 2 (MEF2C), P300/CBP-associated factor
(PCAF), histone deacetylase 1 (HDAC1), fibronectin, vimentin, and collagen I were analysed at 48, 72, and 168 h, by
western blotting or by immunofluorescence staining visualized by confocal microscopy. Studies in mice were performed
in 5- and 24-month-old C57BL6 mice. Three months before sacrifice, 21-month-old mice were fed with a standard diet or
a low phosphate diet, containing 0.6% or 0.2% phosphate, respectively. Serum phosphate concentration was assessed by
a colorimetric method and forelimb strength by a grip test. Fibrosis was observed in the tibialis anterior muscle by Sirius
Red staining. In gastrocnemius muscle, MyoG, MEF2C, and fibronectin expressions were analysed by western blotting.
Results Cells differentiated in the presence of BGP showed near five times less expression of troponin T and kept
higher levels of Pax-7 than control cells indicating a reduced myogenic differentiation. BGP reduced Myf5 about
50% and diminished MyoD transcriptional activity by increasing the expression of HDAC1 and reducing the expression
of PCAF. Consequently, BGP reduced to 50% the expression of MyoG and MEF2C. A significant increase in the expression
of fibrosis markers as collagen I, vimentin, and fibronectin was found in cells treated with BGP. In mice, serum
phosphate (17.24 ± 0.77 mg/dL young; 23.23 ± 0.81 mg/dL old; 19.09 ± 0.75 mg/dL old with low phosphate diet)
correlates negatively (r = 0.515, P = 0.001) with the muscular strength (3.13 ± 0.07 gf/g young; 1.70 ± 0.12 gf/
g old; 2.10 ± 0.09 gf/g old with low phosphate diet) and with the expression of MyoG (r = 0.535, P = 0.007) and
positively with the expression of fibronectin (r = 0.503, P = 0.001) in gastrocnemius muscle. The tibialis anterior muscle
from old mice showed muscular fibrosis. Older mice fed with a low phosphate diet showed improved muscular parameters
relative to control mice of similar age.
Conclusions Hyperphosphatemia impairs myogenic differentiation, by inhibiting the transcriptional activity of MyoD,
and enhances the expression of fibrotic genes in cultured myoblasts. Experiments carried out in older mice demonstrate
a close relationship between age-related hyperphosphatemia and the decrease in the expression of myogenic factors
and the increase in factors related to muscle fibrosis.Instituto de Salud Carlos IIIPrincipado de AsturiasComunidad de Madri
Hyperphosphatemia-Induced Oxidant/Antioxidant Imbalance Impairs Vascular Relaxation and Induces Inflammation and Fibrosis in Old Mice
Aging impairs vascular function, but the mechanisms involved are unknown. The aim of this study was to analyze whether aging-related hyperphosphatemia is implied in this effect by elucidating the role of oxidative stress. C57BL6 mice that were aged 5 months (young) and 24 months (old), receiving a standard (0.6%) or low-phosphate (0.2%) diet, were used. Isolated mesenteric arteries from old mice showed diminished endothelium-dependent vascular relaxation by the down-regulation of NOS3 expression, increased inflammation and increased fibrosis in isolated aortas, compared to those isolated from young mice. In parallel, increased Nox4 expression and reduced Nrf2, Sod2-Mn and Gpx1 were found in the aortas from old mice, resulting in oxidant/antioxidant imbalance. The low-phosphate diet improved vascular function and oxidant/antioxidant balance in old mice. Mechanisms were analyzed in endothelial (EC) and vascular smooth muscle cells (SMCs) treated with the phosphate donor ss-glycerophosphate (BGP). In EC, BGP increased Nox4 expression and ROS production, which reduced NOS3 expression via NF kappa B. BGP also increased inflammation in EC. In SMC, BGP increased Collagen I and fibronectin expression by priming ROS production and NF kappa B activity. In conclusion, hyperphosphatemia reduced endothelium-dependent vascular relaxation and increased inflammation and vascular fibrosis through an impairment of oxidant/antioxidant balance in old mice. A low-phosphate diet achieved improvements in the vascular function in old mice
- …