Monolithically multi-color lasing from an InGaN microdisk on a Si substrate

An optically pumped multi-color laser has been achieved using an InGaN/GaN based micro-disk with an undercut structure on a silicon substrate. The micro-disk laser has been fabricated by means of a combination of a cost-effective microsphere lithography technique and subsequent dry/wet etching processes. The microdisk laser is approximately 1 μm in diameter. The structure was designed in such a way that the vertical components of the whispering gallery (WG) modes formed can be effectively suppressed. Consequently, three clean lasing peaks at 442 nm, 493 nm and 522 nm have been achieved at room temperature by simply using a continuous-wave diode laser as an optical pumping source. Time–resolved micro photoluminescence (PL) measurements have been performed in order to further confirm the lasing by investigating the excitonic recombination dynamics of these lasing peaks. A three dimensional finite-difference-time-domain (FDTD) simulation has been used for the structure design

Silicon Mie Resonators for Highly Directional Light Emission from monolayer MoS2

Controlling light emission from quantum emitters has important applications ranging from solid-state lighting and displays to nanoscale single-photon sources. Optical antennas have emerged as promising tools to achieve such control right at the location of the emitter, without the need for bulky, external optics. Semiconductor nanoantennas are particularly practical for this purpose because simple geometries, such as wires and spheres, support multiple, degenerate optical resonances. Here, we start by modifying Mie scattering theory developed for plane wave illumination to describe scattering of dipole emission. We then use this theory and experiments to demonstrate several pathways to achieve control over the directionality, polarization state, and spectral emission that rely on a coherent coupling of an emitting dipole to optical resonances of a Si nanowire. A forward-to-backward ratio of 20 was demonstrated for the electric dipole emission at 680 nm from a monolayer MoS2 by optically coupling it to a Si nanowire

A quantitative mass spectrometry-based approach to monitor the dynamics of endogenous chromatin-associated protein complexes.

Understanding the dynamics of endogenous protein-protein interactions in complex networks is pivotal in deciphering disease mechanisms. To enable the in-depth analysis of protein interactions in chromatin-associated protein complexes, we have previously developed a method termed RIME (Rapid Immunoprecipitation Mass spectrometry of Endogenous proteins). Here, we present a quantitative multiplexed method (qPLEX-RIME), which integrates RIME with isobaric labelling and tribrid mass spectrometry for the study of protein interactome dynamics in a quantitative fashion with increased sensitivity. Using the qPLEX-RIME method, we delineate the temporal changes of the Estrogen Receptor alpha (ERα) interactome in breast cancer cells treated with 4-hydroxytamoxifen. Furthermore, we identify endogenous ERα-associated proteins in human Patient-Derived Xenograft tumours and in primary human breast cancer clinical tissue. Our results demonstrate that the combination of RIME with isobaric labelling offers a powerful tool for the in-depth and quantitative characterisation of protein interactome dynamics, which is applicable to clinical samples

Energy Frontier Research Center for Solid-State Lighting Science: Exploring New Materials Architectures and Light Emission Phenomena

The Energy Frontier Research Center (EFRC) for Solid-State Lighting Science (SSLS) is one of 46 EFRCs initiated in 2009 to conduct basic and use-inspired research relevant to energy technologies. The overarching theme of the SSLS EFRC is the exploration of energy conversion in tailored photonic structures. In this article we review highlights from the research of the SSLS EFRC. Major research themes include: studies of the materials properties and emission characteristics of III-nitride semiconductor nanowires; development of new phosphors and II−VI quantum dots for use as wavelength downconverters; fundamental understanding of competing radiative and nonradiative processes in current-generation, planar light-emitting diode architectures; understanding of the electrical, optical, and structural properties of defects in InGaN materials and heterostructures; exploring ways to enhance spontaneous emission through modification of the environment in which the emission takes place; and investigating routes such as stimulated emission that might outcompete nonradiative processes

Living near the water. Environment, wetland economy and fishing techniques of the Mesolithic site Galgenbühel/Dos de la Forca in the Adige Valley (South Tyrol, Italy)

The Mesolithic faunal record recovered from the Galgenbühel/Dos de la Forca rock-shelter at Salorno/Salurn (Bolzano/South Tyrol, Italy, Eastern Alps) allows the reconstruction of the landscape and local environmental conditions in the Adige valley bottom during the Early Holocene thanks to the analysis of the species ecology. The predominance of a highly differentiated spectrum of species related to wetland contexts, largely the result of human predation, indicates a reduced catchment area with a high biodiversity exploited by the Sauveterrian fisher-hunter-gatherer groups repeatedly occupying the site. Data converge towards a habitat of slack and slow moving waters, bordered by abundant submerged and shore vegetation, and surrounded by forested areas. The intensive exploitation of some fauna such as the pike, the Cyprinidae, small mammals as the beaver and the wild cat as well as Unionidae and Emys orbicularis suggests specialized activities practiced near and on the site. Some particular choices, as the increasing preference for the pike rather than for the Cyprinidae, could possibly be related to consumption habits

Cistromic Reprogramming of the Diurnal Glucocorticoid Hormone Response by High-Fat Diet

The glucocorticoid receptor (GR) is a potent metabolic regulator and a major drug target. While GR is known to play integral roles in circadian biology, its rhythmic genomic actions have never been characterized. Here we mapped GR's chromatin occupancy in mouse livers throughout the day and night cycle. We show how GR partitions metabolic processes by time-dependent target gene regulation and controls circulating glucose and triglycerides differentially during feeding and fasting. Highlighting the dominant role GR plays in synchronizing circadian amplitudes, we find that the majority of oscillating genes are bound by and depend on GR. This rhythmic pattern is altered by high-fat diet in a ligand-independent manner. We find that the remodeling of oscillatory gene expression and postprandial GR binding results from a concomitant increase of STAT5 co-occupancy in obese mice. Altogether, our findings highlight GR's fundamental role in the rhythmic orchestration of hepatic metabolism