Temperature Dependence of Blue Phosphorescent Cyclometalated Ir(III) Complexes

The photophysical properties for a series of facial (fac) cyclometalated Ir(III) complexes (fac-Ir(C^N)_3 (C^N = 2-phenylpyridyl (ppy), 2-(4,6-difluorophenyl)pyridyl (F2ppy), 1-phenylpyrazolyl (ppz), 1-(2,4-difluorophenyl)pyrazolyl) (F2ppz), and 1-(2-(9,9′-dimethylfluorenyl))pyrazolyl (flz)), fac-Ir(C^N)_2(C^N′) (C^N = ppz or F2ppz and C^N′ = ppy or F2ppy), and fac-Ir(CC′)_3 (C^C′ = 1-phenyl-3-methylbenzimidazolyl (pmb)) have been studied in dilute 2-methyltetrahydrofuran (2-MeTHF) solution in a temperature range of 77−378 K. Photoluminescent quantum yields (Φ) for the 10 compounds at room temperature vary between near zero and unity, whereas all emit with high efficiency at low temperature (77 K). The quantum yield for fac-Ir(ppy)_3 (Φ = 0.97) is temperature-independent. For the other complexes, the temperature-dependent data indicates that the luminescent efficiency is primarily determined by thermal deactivation to a nonradiative state. Activation energies and rate constants for both radiative and nonradiative processes were obtained using a Boltzmann analysis of the temperature-dependent luminescent decay data. Activation energies to the nonradiative state are found to range between 1600 and 4800 cm^−1. The pre-exponential factors for deactivation are large for complexes with C^N ligands (1011−1013 s^−1) and significantly smaller for fac-Ir(pmb)_3 (109 s^−1). The kinetic parameters for decay and results from density functional theory (DFT) calculations of the triplet state are consistent with a nonradiative process involving Ir−N (Ir−C for fac-Ir(pmb)_3) bond rupture leading to a five-coordinate species that has triplet metal-centered (^3MC) character. Linear correlations are observed between the activation energy and the energy difference calculated for the emissive and ^3MC states. The energy level for the ^3MC state is estimated to lie between 21700 and 24000 cm^−1 for the fac-Ir(C^N)_3 complexes and at 28000 cm^−1 for fac-Ir(pmb)_3

POLY-METHYL VINYL ETHER-CO-MALEIC ANHYDRIDE NANOPARTICLES AS ANTIGEN DELIVERY AND ACTIVATING SYSTEMS

The incorporation of antigens into poly-methyl vinyl ether-co-maleic anhydride nanoparticles (NP) has demonstrated to enhance the immune responses in terms of a potent Th1-adjuvant capacity. This fact may be explained by the implemented possibilities that NP render to the antigen: controlled release from the vehicle and chemotaxis for APC recruitment. Besides, after oral administration, it was reported that the bioadhesive nature of the polymer enhanced the interaction of the particulate-adjuvant to the gut mucosa. Moreover, these NP allow the adhesion of antigens and ligands to its outer shell, creating high antigen density surfaces that increase the possibilities of antigen recognition and/or capture by the APCs. Taken together, from the ability of NP to induce potent immune responses our hypothesis was that NP are able to trigger determined elements of the immune system. Explicitly, due to their particulate nature, NPs would interact with APCs, specifically DCs, through PRRs, including TLR. Our results revealed that poly(anhydride) NPs act as agonists of various TLRs (2, 4 and 5), triggering a Th1 profile cytokine release (IFN-γ: 478 pg/mL; IL12: 40 pg/mL) and, after incubation with dendritic cells, induce a 2.5 to 3.5 fold increase of CD54 and CD86 costimulatory molecule expression. Furthermore, in vivo studies suggest that NPs actively elicit a CD8+ T cell response. Taken together our results provide a better understanding of how NPs act as active Th1 adjuvants in immunoprophylaxis and immunotherapy through TLR exploitation. Acknowledgements This work was supported by grants from the Instituto de Salud Carlos III - FIS (PI070326) in Spain. References Arbos P, Wirth M, Arangoa MA, Gabor F, Irache JM. Gantrez AN as a new polymer for the preparation of ligand-nanoparticle conjugates. J Control Release 2002;83(3):321-30. Gomez S, Gamazo C, Roman BS, Ferrer M, Sanz ML, Irache JM. Gantrez AN nanoparticles as an adjuvant for oral immunotherapy with allergens. Vaccine 2007;25(29):5263-71. Irache JM, Salman HH, Gomez S, Espuelas S, Gamazo C. Poly(anhydride) nanoparticles as adjuvants for mucosal vaccination. Frontiers in Bioscience 2009. Ochoa J, Irache JM, Tamayo I, Walz A, DelVecchio VG, Gamazo C. Protective immunity of biodegradable nanoparticle-based vaccine against an experimental challenge with Salmonella Enteritidis in mice. Vaccine 2007;25(22):4410-9. Salman HH, Irache JM, Gamazo C. Immunoadjuvant capacity of flagellin and mannosamine-coated poly(anhydride) nanoparticles in oral vaccination. Vaccine 2009;27(35):4784-90

Numerical Simulation of Nano Scanning in Intermittent-Contact Mode AFM under Q control

We investigate nano scanning in tapping mode atomic force microscopy (AFM) under quality (Q) control via numerical simulations performed in SIMULINK. We focus on the simulation of whole scan process rather than the simulation of cantilever dynamics and the force interactions between the probe tip and the surface alone, as in most of the earlier numerical studies. This enables us to quantify the scan performance under Q control for different scan settings. Using the numerical simulations, we first investigate the effect of elastic modulus of sample (relative to the substrate surface) and probe stiffness on the scan results. Our numerical simulations show that scanning in attractive regime using soft cantilevers with high Qeff results in a better image quality. We, then demonstrate the trade-off in setting the effective Q factor (Qeff) of the probe in Q control: low values of Qeff cause an increase in tapping forces while higher ones limit the maximum achievable scan speed due to the slow response of the cantilever to the rapid changes in surface profile. Finally, we show that it is possible to achieve higher scan speeds without causing an increase in the tapping forces using adaptive Q control (AQC), in which the Q factor of the probe is changed instantaneously depending on the magnitude of the error signal in oscillation amplitude. The scan performance of AQC is quantitatively compared to that of standard Q control using iso-error curves obtained from numerical simulations first and then the results are validated through scan experiments performed using a physical set-up

Innovación curricular con el aprendizaje basado en problema en estudios universitarios : estudio de caso

Este artículo presenta una investigación cuyo objetivo general ha sido estudiar la cultura de la Escuela Universitaria de Enfermería Vall d'Hebron en la que se ha llevado a cabo una innovación organizativa y curricular fundamentada en el Aprendizaje Basado en Problemas (ABP) como metodología de enseñanza-aprendizaje. Los objetivos específicos han sido: 1) estudiar qué elementos característicos de la cultura innovadora se dan en dicha innovación y 2) contrastar la percepción que tienen los diferentes agentes implicados sobre las fases de la innovación. La metodología de investigación ha sido cualitativa y en el estudio de caso. Se han elaborado dos instrumentos de recogida de información que son las entrevistas en profundidad y el Focus Grup en el que han participado todo el profesorado de la Escuela. Los resultados indican que la autonomía que disponía la Escuela, tanto para la toma de decisiones, como para la gestión económica era una característica fundamental que explica el éxito de la innovación. El liderazgo ejercido por la dirección de la Escuela así como la tradición de trabajo en equipo del profesorado se ha considerado factores imprescindibles. La motivación de todo el equipo para llevar adelante el ABP para erigirse como un centro de referencia también ha sido decisiva así como el continuo asesoramiento de un experto externo durante todo el proceso de cambioThis research has been focused on the curricular innovation within the university framework. The general aim of the research has been the study of the innovation culture in the Escuela Universitaria de Enfermería Vall d'Hebron, using the Problem Based Learning (PBL) methodology. The specific objectives have been: 1) to study those elements of the innovation culture presents in the innovation and 2) to contrast the perception of the different agents implicated in the innovation phases. The research design has been based on the case study. Personal deep interviews and the Focus Group analysis have been used for data collection. The main results of this study have been: 1)the autonomy of the center for making decisions and for economical management 2) the institutional decision favorable to the change supported by the director of the center 3) the work as a team of all the professors of the center, absolutely necessary for make possible the change 4) the interest to be a reference center among other possible competitors 5)to have an external expert during all the process of the change. The teaching experience described in this paper aims to strengthen various aspects of competence of students through a dynamic learning method. The main aim of the experience is none other than making that students learn the basics of the subject, while developing different jurisdictional issues aligned with the student's imminent accession to the labor market. Teaching experience presents a co-assessment system linked to role playing by the student, that make it an appealing and efficient experience from the point of view of learning and skills development of the student. This work provides also a comparison between the results of teaching experience based on peer-assessment and role play with the traditional teaching of the same content during the previous academic year in the same subject but taught with traditional teaching methodolog

Morphology and mobility as tools to control and unprecedentedly enhance X-ray sensitivity in organic thin-films

Organic semiconductor materials exhibit a great potential for the realization of large-area solution-processed devices able to directly detect high-energy radiation. However, only few works investigated on the mechanism of ionizing radiation detection in this class of materials, so far. In this work we investigate the physical processes behind X-ray photoconversion employing bis-(triisopropylsilylethynyl)-pentacene thin-films deposited by bar-assisted meniscus shearing. The thin film coating speed and the use of bis-(triisopropylsilylethynyl)-pentacene:polystyrene blends are explored as tools to control and enhance the detection capability of the devices, by tuning the thin-film morphology and the carrier mobility. The so-obtained detectors reach a record sensitivity of 1.3 \ub7 104 \ub5C/Gy\ub7cm2, the highest value reported for organic-based direct X-ray detectors and a very low minimum detectable dose rate of 35 \ub5Gy/s. Thus, the employment of organic large-area direct detectors for X-ray radiation in real-life applications can be foreseen

El desarrollo profesional del docente de Educación Secundaria a partir del análisis de la cultura docente compartida

El artículo presenta algunos de los resultados obtenidos en un estudio sobre la cultura organizacional y docente de cuatro Institutos de Educación Secundaria de la provincia de Barcelona. Pone de relieve la necesaria modificación de la cultura docente para hacer frente a los retos educativos de la sociedad del siglo XXI. A partir de la adaptación de un cuestionario previamente elaborado para la Universidad por el equipo de investigación sobre "El cambio de cultura de las universidades catalanas al inicio del siglo XXI (CCUC, 2004) se averigua la percepción del profesorado respecto el perfil del profesorado, las metodologías docentes utilizadas, la concepción que tienen del alumnado, las estrategias y formas de evaluar el aprendizaje y la labor docente. Todo ello respecto el presente y lo que para ellos debería ser en un futuro. El estudio pone claramente de manifiesto que existe una insatisfacción del profesorado respecto a cada uno de los aspectos señalados y que ven necesaria una transformación de los IES.This article presents some of the results obtained in a study on the organizational and teaching culture of four high schools. The research, which has been carried out with the support of the DURSI at the province of Barcelona, emphasizes the need to transform the teaching culture so that the educational challenges of the 21st century society can be met. Data are obtained from an adapted version of a questionnaire which was previously designed for the university context by the research team CCUC (2004), and refer to teachers' perception on their teaching profile, teaching methodologies, their approach to students, and the assessment strategies and procedures concerning both teaching and learning. All these issues are explored in relation to both their actual state and their ideal prospects in the future. The research highlights teachers' discomfort with each of these issues as well as their perception on the need to transform high schools

Análisis de los saques de lateral del Torneo de Rugby Seis Naciones 2013

El saque de lateral es una de las formas de reinicio del juego o fases de conquista en un partido de rugby cuantitativa y cualitativamente importante. En este artículo se realizó un estudio descriptivo de los saques de lateral en un torneo internacional de alto nivel. En segundo lugar, se estudiaron las diferencias en esta fase de juego entre los distintos equipos participantes y, finalmente, determinamos las variables que inciden en la conquista de la pelota. A partir de un conjunto inicial de variables se desarrolló, mediante la validación con expertos, una herramienta para la observación de los factores clave. La muestra estuvo constituida por 358 saques de lateral del Torneo Seis Naciones de 2013 que se investigaron mediante análisis de vídeo. Los resultados han mostrado información relevante sobre las variables estudiadas (partido, equipo, casa/fuera, número del saque lateral, iluminación, lluvia, viento, tiempo, resultado, lado, zona, número de jugadores, estructura previa, estructura de salto, posición saltador, cambio de posición, movimiento, amague, ángulo, velocidad, tiempo vuelo, distancia, altura y conquista). Se encontraron diferencias entre los equipos en: el número de jugadores, el ángulo, el tiempo de vuelo y la altura. Por último, entre todas las variables investigadas, encontramos que hay una mayor probabilidad de conquista cuando el tiempo de vuelo dura entre 0,36 y 0,84 s, y la distancia es entre 5 y 10 m

Anàlisi dels serveis de toc del Torneig de Rugbi Sis Nacions 2013

El servei de toc és una de les formes de reinici del joc o fases de conquesta en un partit de rugbi quantitativament i qualitativament important. En aquest article es va fer un estudi descriptiu dels serveis de toc en un torneig internacional d’alt nivell. En segon lloc, es van estudiar les diferències en aquesta fase de joc entre els diferents equips participants i, finalment, es van determinar les variables que incidien en la conquesta de la pilota. A partir d’un conjunt inicial de variables es va desenvolupar, mitjançant la validació amb experts, una eina per a l’observació dels factors clau. La mostra va estar constituïda per 358 serveis de toc del Torneig Sis Nacions de 2013 que es van investigar mitjançant anàlisi de vídeo. Els resultats han mostrat informació rellevant sobre les variables estudiades (partit, equip, casa/fora, número del servei de toc, il·luminació, pluja, vent, temps, resultat, costat, zona, nombre de jugadors, estructura prèvia, estructura de salt, posició saltador, canvi de posició, moviment, finta, angle, velocitat, temps de vol, distància, alçada i conquesta). Es van trobar diferències entre els equips en: el nombre de jugadors, l’angle, el temps de vol i l’alçada. Per últim, entre totes les variables investigades, trobem que hi ha una major probabilitat de conquesta quan el temps de vol dura entre 0,36 i 0,84 s, i la distància és entre 5 i 10 m

Mean Field Behavior of Cluster Dynamics

The dynamic behavior of cluster algorithms is analyzed in the classical mean field limit. Rigorous analytical results below $T_c$ establish that the dynamic exponent has the value $z_{sw}=1$ for the Swendsen-Wang algorithm and $z_{uw}=0$ for the Wolff algorithm. An efficient Monte Carlo implementation is introduced, adapted for using these algorithms for fully connected graphs. Extensive simulations both above and below $T_c$ demonstrate scaling and evaluate the finite-size scaling function by means of a rather impressive collapse of the data.Comment: Revtex, 9 pages with 7 figure