Search results for "Spectrum"
showing 10 items of 2043 documents
Equal opportunities to social inclusion for autistic Children
2014
La tasa de prevalencia de los trastornos del espectro del autismo (TEA) se ha incrementado dramáticamente en los últimos años. El Centro para el Control y la Prevención de Enfermedades de Atlanta estima que aproximadamente 1 de cada 68 niños ha sido identificado con TEA. Los niños con TEA presentan problemas en las habilidades sociales, emocionales, de comunicación y de la vida diaria. Por otra parte, presentan dificultades desde la primera infancia en áreas clave para el aprendizaje y para su desarrollo. Debido a estas características la mayoría de los niños con TEA necesitan programas específicos de inclusión educativa; en este sentido, la acción y la atención temprana es muy importante p…
Spectroscopic signatures for planar equilibrium geometries in methyl-substituted oligothiophenes
2009
In recent studies it was demonstrated that temperature-dependent optical spectroscopy is a valuable tool for revealing the differences in the geometries of flexible molecules like oligothiophenes (OTs) in the ground (S0) and first excited (S1) electronic states, by examining the symmetry relations between the absorption and emission spectra: while at low temperature the spectra show mirror symmetry, pointing to planar geometries in S0 and S1, the symmetry relation breaks down at ambient temperature due to thermal population of torsional modes. In the present joint spectroscopic and theoretical study, we demonstrate that this behavior is also observed for di- and tetramethyl-substituted OTs,…
Origin of the Red Sites and Energy Transfer Rates in Single MEH-PPV Chains at Low Temperature
2011
Single poly[2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) molecules dispersed in thin poly(methylmethacrylate) films have been investigated by fluorescence emission, excitation and time-resolved spectroscopy at 1.2 K. For the molecular weight studied (∼200 kDa) a bimodal distribution of emission maxima is observed. Based on a comparison of the spectroscopic properties of blue and red sites and on polarisation-resolved measurements, we argue in agreement with recent quantum-chemical calculations that the red subpopulation most probably does not arise from interchromophoric excitation delocalisation but is to be attributed to longer chromophoric units originating from orde…
Origin of the large spectral shift in electroluminescence in a blue light emitting cationic iridium(III) complex
2007
A new, but archetypal compound [ Ir( ppy- F-2) (2)Me(4)phen] PF6, where ppy- F2 is 2-(2',4'- fluorophenyl) pyridine and Me(4)phen is 3,4,7,8- tetramethyl- 1,10- phenanthroline, was synthesized and used to prepare a solid-state light-emitting electrochemical cell (LEEC). This complex emits blue light with a maximum at 476 nm when photoexcited in a thin film, with a photoluminescence quantum yield of 52%. It yields an efficient single-component solid-state electroluminescence device with a current efficiency reaching 5.5 cd A(-1) and a maximum power efficiency of 5.8 Lm Watt(-1). However, the electroluminescence spectrum is shifted with respect to the photoluminescence spectrum by 80 nm resul…
Interacción social y comunicación temprana en hermanos de niños con diagnóstico de trastorno del espectro autista: una revisión de la literatura
2017
Los hermanos de niños con trastorno del espectro autista (TEA) tienen un mayor riesgo que la media de la población infantil, entre un 5 y un 10%, de ser después diagnosticados con el trastorno. Por otra parte, algunos de estos hermanos han mostrado, independientemente de ser más tarde diagnosticados, tener dificultades en las interacciones sociales tempranas. ¿Son habituales este tipo de conductas, no necesariamente vinculadas al trastorno, en hermanos de niños con TEA? En el presente trabajo se plantea una revisión bibliográfica para explorar los hallazgos más recientes en respuesta a este interrogante. Las principales conclusiones apuntan a un patrón de comunicación temprana diferente, o …
Mössbauer Emission Spectroscopy of Mixed-Valency after Nuclear Decay in Iron Complexes
1991
The population of anomalous spin states and aliovalent charge states of iron induced by the 57 Co(EC)57 Fe nuclear decay in polycristalline transition metal compounds was studied by means of Coincidence Mossbauer Emission Spectroscopy (CMES), that is Time-Differential Mossbauer Emission Spectroscopy (TDMES) as well as γ/Xray-Coincidence Mossbauer Emission Spectroscopy (γ/X-CMES). By use of time-integral Mossbauer emission spectroscopy (TIMES) we have observed anomalous high spin (S = 2) states of 57 Fe(II) in the system [57Co/Co(phen)3(ClO 4)2 with increasing intensities on lowering the temperature. With TDMES we followed quantitatively the high spin-low spin relaxation kinetics in this com…
Il Protocollo RE4BES per il potenziamento delle abilità cognitive, emotive e sociali di un bambino con disturbo dello spettro autistico
2020
The study reports an intervention study on a child with Autism Spectrum Disorder. The intervention was conducted using some activities included in the RE4BES protocol, a collection of guidelines for the implementation of educational robots intervention for children and young people with special educational eeeds. To assess the efficacy of the intervention, an A-B-A quasi-experimental design was used, in which the involved child was repeatedly evaluated before, during and after treatment. The results showed that robotics activities produced significant changes in his fine motor skills, verbal and preverbal skills, social reciprocity and emotional expression. Furthermore, it was possible to o…
Search for magnetically-induced signatures in the arrival directions of ultra-high-energy cosmic rays measured at the Pierre Auger Observatory
2020
We search for signals of magnetically-induced effects in the arrival directions of ultra-high-energy cosmic rays detected at the Pierre Auger Observatory. We apply two different methods. One is a search for sets of events that show a correlation between their arrival direction and the inverse of their energy, which would be expected if they come from the same point-like source, they have the same electric charge and their deflection is relatively small and coherent. We refer to these sets of events as "multiplets". The second method, called "thrust", is a principal axis analysis aimed to detect the elongated patterns in a region of interest. We study the sensitivity of both methods using a …
Correlative Raman-Electron-Light (CREL) Microscopy Analysis of Lipid Droplets in Melanoma Cancer Stem Cells.
2022
Among all neoplasms, melanoma is characterized by a very high percentage of cancer stem cells (CSCs). Several markers have been proposed for their identification, and lipid droplets (LDs) are among them. Different techniques are used for their characterization such as mass spectrometry, imaging techniques, and vibrational spectroscopies. Some emerging experimental approaches for the study of LDs are represented by correlative light–electron microscopy and by correlative Raman imaging–scanning electron microscopy (SEM). Based on these scientific approaches, we developed a novel methodology (CREL) by combining Raman micro-spectroscopy, confocal fluorescence microscopy, and SEM coupled with an…
Improved calculations of beta decay backgrounds to new physics in liquid xenon detectors
2020
We present high-precision theoretical predictions for the electron energy spectra for the ground-state to ground-state $\beta$ decays of $^{214}$Pb, $^{212}$Pb, and $^{85}$Kr most relevant to the background of liquid xenon dark matter detectors. The effects of nuclear structure on the spectral shapes are taken into account using large-scale shell model calculations. Final spectra also include atomic screening and exchange effects. The impact of nuclear structure effects on the $^{214}$Pb and $^{212}$Pb spectra below $\approx100$ keV, pertinent for several searches for new physics, are found to be comparatively larger than those from the atomic effects alone. We find that the full calculatio…