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InGaN micro-LEDs (μ LEDs) with their potential high-volume applications have attracted substantial research interest in the past years. In comparison to other III–V semiconductors, InGaN exhibits a reduced susceptibility toward non-radiative surface recombination. However, efficiency degradation becomes more prominent as dimensions shrink to a few μ m or less. Due to the high surface-to-volume ratio of the miniaturized devices, the non-radiative recombination increases and reduces the internal quantum efficiency. While many groups focus on surface passivation to mitigate surface defects, the influence of crystallographic orientation of the μ LED sidewall on the efficiency remains unexplored. This study addresses this gap by investigating the impact of crystallographic orientation of the sidewalls on the emission properties of the μ LEDs. Hexagonal and elongated μ LEDs with dimensions as small as 3.5 μ m and sidewalls with crystallographically well-defined m- and a-planes were fabricated. Electrical and optical properties were investigated using photo- and electroluminescence. External quantum efficiency (EQE) is assessed based on well-known carrier recombination models. It can be shown that μ LED performance intrinsically depends on the crystallographic orientation of the sidewalls. Comparing hexagonal μ LED structures with a-plane and m-plane sidewalls, an increase in the EQE by 33 % was observed for structures with a-plane sidewalls, accompanied by reduction in the current density of the peak EQE by a nearly two orders of magnitude compared to structures with m-plane sidewalls. By analyzing the EQE characteristics at the μ LED center and near the sidewalls, the improvements can be directly attributed to the increased radiative recombination from sidewalls with a-plane orientation. [ABSTRACT FROM AUTHOR]

Dothideomycetes is the largest class of kingdom Fungi and comprises an incredible diversity of lifestyles, many of which have evolved multiple times. Plant pathogens represent a major ecological niche of the class Dothideomycetes and they are known to infect most major food crops and feedstocks for biomass and biofuel production. Studying the ecology and evolution of Dothideomycetes has significant implications for our fundamental understanding of fungal evolution, their adaptation to stress and host specificity, and practical implications with regard to the effects of climate change and on the food, feed, and livestock elements of the agro-economy. In this study, we present the first large-scale, whole-genome comparison of 101 Dothideomycetes introducing 55 newly sequenced species. The availability of whole-genome data produced a high-confidence phylogeny leading to reclassification of 25 organisms, provided a clearer picture of the relationships among the various families, and indicated that pathogenicity evolved multiple times within this class. We also identified gene family expansions and contractions across the Dothideomycetes phylogeny linked to ecological niches providing insights into genome evolution and adaptation across this group. Using machine-learning methods we classified fungi into lifestyle classes with >95 % accuracy and identified a small number of gene families that positively correlated with these distinctions. This can become a valuable tool for genome-based prediction of species lifestyle, especially for rarely seen and poorly studied species.

Livestock production has a variety of environmental impacts such as greenhouse gas emissions, water pollution, acidification, and primary energy consumption. The demand for livestock products is expected to grow substantially, creating even more environmental pressure. The use of specialty feed ingredients (SFI) such as supplemented AA and phytase can reduce nutrient input into the system without compromising productivity and consequently can reduce emissions. The global change impact of using SFI in pig and broiler production systems in Europe and North and South America was studied. A life cycle assessment according to international standards (ISO 14040/44) analyzed contributions from producing SFI and animals to global change. Three different alternatives were analyzed. In addition, partial sensitivity analysis was conducted using 5 scenarios for each region for both production systems. Specialty feed ingredient supplementation in pig and broiler diets reduced greenhouse gas emissions (cradle to farm gate) by 56% and 54% in Europe, 17% and 15% in North America, and 33% and 19% in South America, respectively, compared to an unsupplemented diet. A total of 136 Mt CO equivalent (CO eq) was saved in 2012, rising to 146 Mt CO eq in 2050 on the basis of United Nations population projections. Considerable benefits of supplementation with SFI were apparent in European and South American diets when direct land use change was considered because of the reduced demand for soybean meal. The eutrophication potential of unsupplemented diets was reduced by up to 35% in pig and 49% in broiler production systems compared to supplemented alternatives. The acidification potential of supplemented strategies was reduced by up to 30% in pig and 79% in broiler production systems. The primary energy demand was similar in all alternatives, and this could be an area where the SFI industry can improve. Overall, SFI supplementation substantially reduced the global warming, eutrophication, and acidification potentials in all regions studied.

Building on evidence that Latino voters participate at higher rates when co-ethnic candidates appear on the ballot, we report the results from a field experiment examining whether co-ethnic policy leadership can produce similar mobilization in direct democracy elections. The study features a direct-mail campaign conducted during California’s 2010 statewide primary election aimed at mobilizing Latino voters. The experiment included variation in the language of the message sent to voters and the extent to it emphasized the pivotal role played by a prominent Latino official in placing the policy on the ballot. We find that mobilization messages are most effective when they target voters using their preferred language, at least for English-dominant Latinos. By contrast, our experiment yielded no evidence that co-ethnic policy leadership increased voter turnout, although we do show that female voters participate at higher rates when the mobilization campaign prominently features a high-profile female official. These divergent effects provide lessons for the study of ethnic political participation and for the design of effective mobilization campaigns aimed at boosting Latino turnout.