Near-field light emission from semiconductor macroatoms

We present a microscopic theoretical analysis of time and spatially resolved photoluminescence of naturally occurring quantum dots induced by monolayer fluctuations in the thickness of semiconductor quantum wells. In particular we study the carrier dynamics and the emission properties of a semiconductor quantum dot under both continuous-wave and pulsed excitations resonant with the barrier energy levels. We show that collection-mode near-field optical microscopy allows the detection of light emission from excitonic dark states. We find that, at low temperature, the second (dark) energy level displays a carrier density significantly larger than that of the lowest energy level. This behaviour is a consequence of carrier trapping due to the symmetry-induced suppression of radiative recombination

Psychology for the Common Good: The Interdependence of Citizenship, Justice, and Well-being across the Globe

Ye

ETV5 links the FGFR3 and Hippo signalling pathways in bladder cancer

Activating mutations of fibroblast growth factor receptor 3 (FGFR3) are common in urothelial carcinoma of the bladder (UC). Silencing or inhibition of mutant FGFR3 in bladder cancer cell lines is associated with decreased malignant potential, confirming its important driver role in UC. However, understanding of how FGFR3 activation drives bladder malignant transformation remains limited. We have previously shown that mutant FGFR3 alters the cell-cell and cell-matrix adhesion properties of urothelial cells, resulting in loss of contact-inhibition of proliferation. In this study, we investigate a transcription factor of the ETS-family, ETV5, as a putative effector of FGFR3 signalling in bladder cancer. We show that FGFR3 signalling induces a MAPK/ERK-mediated increase in ETV5 levels, and that this results in increased level of TAZ, a co-transcriptional regulator downstream of the Hippo signalling pathway involved in cell-contact inhibition. We also demonstrate that ETV5 is a key downstream mediator of the oncogenic effects of mutant FGFR3, as its knockdown in FGFR3-mutant bladder cancer cell lines is associated with reduced proliferation and anchorage-independent growth. Overall this study advances our understanding of the molecular alterations occurring during bladder malignant transformation and indicates TAZ as a possible therapeutic target in FGFR3-dependent bladder tumours

Simultaneous biochemical and physiological responses of the roots and leaves of pancratium maritimum (Amaryllidaceae) to mild salt stress

Pancratium maritimum (Amaryllidaceae) is a bulbous geophyte growing on coastal sands. In this study, we investigated changes in concentrations of metabolites in the root and leaf tissue of P. maritimum in response to mild salt stress. Changes in concentrations of osmolytes, glutathione, sodium, mineral nutrients, enzymes, and other compounds in the leaves and roots were measured at 0, 3, and 10 days during a 10‐day exposure to two levels of mild salt stress, 50 mM NaCl or 100 mM NaCl in sandy soil from where the plants were collected in dunes near Cuma, Italy. Sodium accumulated in the roots, and relatively little was translocated to the leaves. At both concentrations of NaCl, higher values of the concentrations of oxidized glutathione disulfide (GSSG), compared to reduced glutathione (GSH), in roots and leaves were associated with salt tolerance. The concentration of proline increased more in the leaves than in the roots, and glycine betaine increased in both roots and leaves. Differences in the accumulation of organic osmolytes and electron donors synthesized in both leaves and roots demonstrate that osmoregulatory and electrical responses occur in these organs of P. maritimum under mild salt stress

Characterisation of microstructure and creep properties of alloy 617 for high-temperature applications

Current energy drivers are pushing research in power generation materials towards improved efficiency and improved environmental impact. In the context of new generation ultra-supercritical (USC) power plant, this is represented by increased efficiency, service temperature reaching 750. °C, pressures in the range of 35-37.5. MPa and associated carbon capture technology. Ni base alloys are primary candidate materials for long term high temperature applications such as boilers. The transition from their current applications, which have required lower exposure times and milder corrosive environments, requires the investigation of their microstructural evolution as a function of thermo-mechanical treatment and simulated service conditions, coupled with modelling activities that are able to forecast such microstructural changes. The lack of widespread microstructural data in this context for most nickel base alloys makes this type of investigation necessary and novel. Alloy INCONEL 617 is one of the Ni-base candidate materials. The microstructures of four specimens of this material crept at temperatures in the 650-750. °C range for up to 20,000. h have been characterised and quantified. Grain structure, precipitate type and location, precipitate volume fraction, size and inter-particle spacing have been determined. The data obtained are used both as input for and validation of a microstructurally-based CDM model for forecasting creep properties

Expresión de p53, proteína bcl-2 y ki-67 en carcinomas basocelulares

Objetivo: Determinar la expresión de las proteínas p53, bcl-2 y Ki-67 en distintas variantes histológicas del carcinoma basocelular. Diseño del estudio: Estudio piloto de variables inmunohistoquímicas (p53, Bcl-2 y ki67) en 20 carcinomas basocelulares diagnosticados y tratados a lo largo de un periodo de 9 meses. Resultados: La inmunotinción fue positiva en el 35% de los casos para la proteína p53 y en el 70% para la proteína Bcl-2. La expresión proteica de Ki-67 osciló entre un mínimo de 0% y un máximo de 60%. Conclusiones: Podríamos concluir que el índice de proliferación celular medido con el anticuerpo Ki-67 es negativa en las formas nodulares y positiva en las no nodulares, la expresión de la proteína Bcl-2 es débilmente positiva en las variantes no nodulares y por último la expresión de p53 mutado si bien se ve en ambos grupos, tiene mayor expresión en las formas no nodulares. Se necesitarían estudios con mayor volumen de pacientes y grupo control para que estos resultados sean estadísticamente significativos

High-power corrugates waveguide components for mm-wave fusion heating systems

Considerable progress has been made over the last year in the U.S., Japan, Russia, and Europe in developing high power long pulse gyrotrons for fusion plasma heating and current drive. These advanced gyrotrons typically operate at a frequency in the range 82 GHz to 170 GHz at nearly megawatt power levels for pulse lengths up to 5 s. To take advantage of these new microwave sources for fusion research, new and improved transmission line components are needed to reliably transmit microwave power to plasmas with minimal losses. Over the last year, General Atomics and collaborating companies (Spinner GmbH in Europe and Toshiba Corporation in Japan) have developed a wide variety of new components which meet the demanding power, pulse length, frequency, and vacuum requirements for effective utilization of the new generation of gyrotrons. These components include low-loss straight corrugated waveguides, miter bends, miter bend polarizers, power monitors, waveguide bellows, de breaks, waveguide switches, dummy loads, and distributed windows. These components have been developed with several different waveguide diameters (32, 64, and 89 mm) and frequency ranges (82 GHz to 170 GHz). This paper describes the design requirements of selected components and their calculated and measured performance characteristics

Estudio clínico y epidemiológico de las enfermedades ampollosas autoinmunes en la Cátedra de Dermatología de la Facultad de Ciencias Médicas de la Universidad Nacional de Asunción. Años 2002 – 2007

Introducción: Las enfermedades ampollosas autoinmunes constituyen un grupo de entidades relativamente infrecuentes caracterizadas por la presencia de ampollas y originadas por un mecanismo autoinmune. Se clasifican en intraepidérmicas y subepidérmicas. Objetivo: Describir la frecuencia y las características clínicas de los pacientes con enfermedades ampollares autoinmunes en la Cátedra de Dermatología del Hospital de Clínicas. FCM - UNA. Clasificar y subclasificar los tipos de enfermedades ampollares autoinmunes. Material y Método: El presente trabajo es un estudio descriptivo de corte trasversal, retrospectivo de 3000 consultas de la Cátedra de Dermatología del Hospital de Clínicas en el periodo 2002-2007. Resultado: Se encontraron 71 pacientes con enfermedades ampollares autoinmunes que hacen un 2,73% de frecuencia. Siendo el Pénfigo Foliáceo más frecuentes con 36 pacientes que hacen un 56,7%. Conclusión: Las enfermedades ampollares constituyeron una patología de consulta importante en la Cátedra de Dermatología del Hospital de Clínicas