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Al2O3 binders of various particle sizes were used to formulate a zeolite Y-based catalyst, and the acidity of catalysts increases with decreasing Al2O3 particle size. Characterization results showe...

The modulation bandwidth of white light emitting diodes (LEDs) is an important factor in visible light communication (VLC) system, which is mainly limited by the down-conversion materials. The broad spectrum and long lifetime of conventional light conversion materials represent an obstacle to future technological developments. Here, we show that inorganic semiconductor perovskite nanocrystals offer a promising alternative nanomaterial. Anion exchange between different perovskite nanocrystals by post-synthesis is a highly efficient protocol to tune the chemical composition and optoelectronic properties of lead halide perovskite nanocrystals. The fine-tuning of the nanocrystal fluorescence is achieved by 2 blending colloidal solutions of CsPb(Br/I)3 lead halide perovskites with different content of halide. The tunable optical emission and short fluorescence lifetime (< 5 ns) of the nanocrystals are exploited to realize white LEDs with a high modulation bandwidth (0.7 GHz), offering a potential route towards fast, energy efficient visible light communication.

While named entity recognition (NER) is a key task in natural language processing, most approaches only target flat entities, ignoring nested structures which are common in many scenarios. Most existing nested NER methods traverse all sub-sequences which is both expensive and inefficient, and also don't well consider boundary knowledge which is significant for nested entities. In this paper, we propose a joint entity mention detection and typing model via prior boundary knowledge (BoningKnife) to better handle nested NER extraction and recognition tasks. BoningKnife consists of two modules, MentionTagger and TypeClassifier. MentionTagger better leverages boundary knowledge beyond just entity start/end to improve the handling of nesting levels and longer spans, while generating high quality mention candidates. TypeClassifier utilizes a two-level attention mechanism to decouple different nested level representations and better distinguish entity types. We jointly train both modules sharing a common representation and a new dual-info attention layer, which leads to improved representation focus on entity-related information. Experiments over different datasets show that our approach outperforms previous state of the art methods and achieves 86.41, 85.46, and 94.2 F1 scores on ACE2004, ACE2005, and NNE, respectively., Work performed at Microsoft Research Asia between 2019/2020

Inorganic perovskite nanocrystals (NCs) have demonstrated a number of unique optical and electronic properties for optoelectronic applications. However, the physical properties of these nanostructures, such as the dynamics of charge carriers on different timescales and their effect on the optical recombination of carriers, are not yet fully understood. This work reports on a slow (>1s) reversible quenching of the NC photoluminescence due to a light-induced Stark effect involving defects on the surface of the NCs and the redistribution of photoexcited carriers onto the NC surface. This phenomenon can influence the operation of optoelectronic devices based on these NCs, including hybrid photosensors based on graphene decorated with inorganic perovskite NCs, revealing their prospects and limitations.

Different amounts of SiO2 were added to the Al2O3 binders to investigate the binder effect on zeolite Y-based catalysts. The added SiO2 improved the mesopore volume and acidity of the catalysts. Characterization results showed that the catalysts' acid amount increased with increasing the SiO2 amount in the binder, which achieved maximum value when 12% SiO2 was added to the binder. The doped SiO2 in Al2O3 binders improved the Al2O3 phase transformation temperature, which is crucial for Al species to break out of the phase energy and migrate into the zeolite. The lifetime of catalyst Y-Al2O3-12SiO2 is 3.7 times higher than that of Y-Al2O3-0SiO2, and the selectivity of the target products simultaneously improved by 7 percentage point. This work should bring some inspiration to the design and application of zeolite-based catalysts.

Ya Feng, Wuchao Liu, Lizhen Pan, Cong Jiang, Chengxi Zhang, Yuxuan Lu, Zhiyu Nie, Lingjing Jin Department of Neurology, Shanghai Tongji Hospital, Tongji University School of Medicine, Shanghai, People’s Republic of China Abstract: Four botulinumtoxin type A (BoNT/A) products, onabotulinumtoxinA (A/Ona), incobotulinumtoxinA (A/Inco), lanbotulinumtoxinA (A/Lan) and chinbotulinumtoxinA (A/Chin), are applied in the present study, among which A/Chin is newly produced. We aimed to compare the neurotoxic potency of these toxins by the gauge of muscle strength reduction. Furthermore, potential molecular and cellular mechanisms were also explored. According to our data, muscle strengths in the four toxin groups were all significantly decreased after injection for 1week. A/Chin achieved the most obvious reduction in muscle strength as compared to the other three products at the dose of 0.5U. However, there was no difference between the four toxins when increased to 2U. As the toxins wore off, muscle strength recovered to basal level 12 weeks postinjection. We further measured the expression levels of key factors involved in neuromuscular junction stabilization and muscle genesis. Our results showed that nicotinic acetylcholine receptor, myogenic regulatory factors and muscle-specific receptor tyrosine kinase were all significantly upregulated upon BoNT/A treatment. Consistent with the result of muscle strength, A/Chin had the most obvious induction of gene expression. Moreover, we also found local inflammation response following BoNT/A injection. Owing to lack of complexing proteins, both A/Inco and A/Chin stimulated relatively lighter inflammation compared to that of A/Ona and A/Lan groups. In conclusion, our study provided evidence for the efficacy of the novel A/Chin and its similar functional mode to that of A/Ona, A/Inco and A/Lan. In addition, A/Chin has superiority in inducing muscle paralysis and inflammation stimulation, which may indicate faster onset and longer duration of this novel A/Chin. Keywords: A/Chin, A/Lan, A/Ona, A/Inco, neurotoxic potency

This paper examines whether foreign direct investment (FDI) affects economic growth in developing countries within the standard neoclassical growth framework, based on data for 127 developing countries over the period 1970-2004. Both Ordinary Least Squares (OLS) and dynamic panel data estimation with fixed effects are used to assess this relationship. The results suggest that FDI does have direct positive effects on economic growth, and the effects of FDI are not contingent on the “absorptive capacity” of recipient countries.