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Quantum dot white light-emitting diodes (QD-WLEDs) were fabricated from green- and red-emitting AgInS2/ZnS core/shell QDs coated on GaN LEDs. Their electroluminescence (EL) spectra were measured at different currents, ranging from...
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Quantum dot white light-emitting diodes (QD-WLEDs) were fabricated from green- and red-emitting AgInS2/ZnS core/shell QDs coated on GaN LEDs. Their electroluminescence (EL) spectra were measured at different currents, ranging from 50 mA to 400 mA, and showed good color stability. The modulation bandwidth of previously prepared QD-WLEDs was confirmed to be much wider than that of YAG:Ce phosphor-based WLEDs. These results indicate that the AgInS2/ZnS core/shell QDs are good color-converting materials for WLEDs and they are capable in visible light communication (VLC).
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Orchardgrass (Dactylis glomerata L.), is a well-known perennial forage species; however, rust diseases have caused a noticeable reduction in the quality and production of orchardgrass. In this study, genetic diversity was assessed...
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Orchardgrass (Dactylis glomerata L.), is a well-known perennial forage species; however, rust diseases have caused a noticeable reduction in the quality and production of orchardgrass. In this study, genetic diversity was assessed and the marker-trait associations for rust were examined using 18 EST-SSR and 21 SCoT markers in 75 orchardgrass accessions. A high level of genetic diversity was detected in orchardgrass with an average genetic diversity index of 0.369. For the EST-SSR and SCoT markers, 164 and 289 total bands were obtained, of which 148 (90.24%) and 272 (94.12%) were polymorphic, respectively. Results from an AMOVA analysis showed that more genetic variance existed within populations (87.57%) than among populations (12.43%). Using a parameter marker index, the efficiencies of the EST-SSR and SCoT markers were compared to show that SCoTs have higher marker efficiency (8.07) than EST-SSRs (4.82). The results of a UPGMA cluster analysis and a STRUCTURE analysis were both correlated with the geographic distribution of the orchardgrass accessions. Linkage disequilibrium analysis revealed an average r2 of 0.1627 across all band pairs, indicating a high extent of linkage disequilibrium in the material. An association analysis between the rust trait and 410 bands from the EST-SSR and SCoT markers using TASSEL software revealed 20 band panels were associated with the rust trait in both 2011 and 2012. The 20 bands obtained from association analysis could be used in breeding programs for lineage selection to prevent great losses of orchardgrass caused by rust, and provide valuable information for further association mapping using this collection of orchardgrass.
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SUMMARY High‐affinity phosphate (Pi) transporters (PHTs) PHT1;1 and PHT1;4 are necessary for plant root Pi uptake especially under Pi‐deficient conditions, but how their protein stability is modulated remains elusive. Here, we i...
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SUMMARY High‐affinity phosphate (Pi) transporters (PHTs) PHT1;1 and PHT1;4 are necessary for plant root Pi uptake especially under Pi‐deficient conditions, but how their protein stability is modulated remains elusive. Here, we identified a Ttransfer DNA insertion mutant of Sorting Nexin1 (SNX1), which had more Pi content and less anthocyanin accumulation than the wild type under deficient Pi. By contrast, the snx1‐2 mutant displayed higher sensitivity to exogenous arsenate in terms of seed germination and root elongation, revealing higher Pi uptake rates. Further study showed that SNX1 could co‐localize and interact with PHT1;1 and PHT1;4 in vesicles and at the plasma membrane. Genetic analysis showed that increased Pi content in the snx1‐2 mutant under low Pi conditions could be extensively compromised by mutating PHT1;1 in the double mutant snx1‐2 pht1;1, revealing that SNX1 is epistatic to PHT1;1. In addition, SNX1 negatively controls PHT1;1 protein stability; therefore, PHT1;1 protein abundance in the plasma membrane was increased in the snx1‐2 mutant compared with the wild type under either sufficient or deficient Pi. Together, our study (i) identifies SNX1 as a key modulator of the plant response to low Pi and (ii) unravels its role in the modulation of PHT1;1 protein stability, PHT1;1 accumulation at the plasma membrane, and root Pi uptake.
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Rich tetrapod ichnofaunas, known for more than a decade, from the Huangyangquan Reservoir (Wuerhe District, Karamay City, Xinjiang) have been an abundant source of some of the largest Lower Cretaceous track collections from China....
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Rich tetrapod ichnofaunas, known for more than a decade, from the Huangyangquan Reservoir (Wuerhe District, Karamay City, Xinjiang) have been an abundant source of some of the largest Lower Cretaceous track collections from China. They originate from inland lacustrine clastic exposures of the 581–877 m thick Tugulu Group, variously divided into four formations and subgroups in the northwestern margin of the Junggar Basin. The large Huangyangquan track assemblages occur in the Lower layer/Subgroup II. Similarly-composed track assemblages also occur at the smaller Asphaltite site in the Upper Layer/Subgroup III. The Huangyangquan assemblages have yielded more than 1,500 identified tracks including abundant tracks of avian and non-avian theropods, pterosaurs and turtles and less abundant tracks of stegosaurs. Previous avian track identifications have been reassessed to conclude that Moguiornipes robustus is a taphotaxon and Koreanaornis dodsoni might be better accommodated in the ichnogenus Aquatilavipes which appears to be the dominant avian ichnotaxon. The avian track Ignotornis is also recognized and represents the first occurrence of this ichnogenus in China. Although the Huangyangquan assemblages lack some of the larger components (e.g., sauropodan and ornithopodan tracks) known from other Lower Cretaceous localities, the association of abundant tracks of smaller tetrapods (avian and non-avian theropods, pterosaurs and turtles) appears to be representative of lacustrine basin faunas of this region, and are an excellent example of the shorebird ichnocoenosis/ichnofacies concept. This is the first comprehensive review and re-analysis of an important Lower Cretaceous ecosystem.
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Piezocatalysis, an evolving catalytic technology built on the piezoelectric properties of catalysts, breaks down the barrier between mechanical energy and chemical energy. The potential difference that arises from the mechanical d...
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Piezocatalysis, an evolving catalytic technology built on the piezoelectric properties of catalysts, breaks down the barrier between mechanical energy and chemical energy. The potential difference that arises from the mechanical deformation of a piezoelectric material is commonly termed 'piezopotential'. Piezopotential has been demonstrated to facilitate the manipulation of band structure and/or charge carrier separation. Despite significant efforts to design materials and understand the mechanism of piezoelectrically enhanced chemistry through semiconductor physics, there remains an opportunity to review the relationships between catalytic performance and piezo/ferroelectric properties. Herein, we provide a comprehensive summary of the catalytic mechanisms and correlated piezo/ferroelectric physical mechanism in the field of piezocatalysis. A fundamental understanding of piezo/ferroelectric structural design based on solid-state physics can be used to shed light on the future development of piezocatalysis. In addition, the types of piezoelectric materials, the design strategies for catalysis efficiency enhancement, and the up-to-date applications in environment remediation, renewable energy conversion, biomedicine and biotechnology are discussed. Finally, future perspectives for designing and developing highly active piezocatalysts using the guidelines of physicochemical relationships are proposed.
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The rapid development of two-dimensional (2D) transition-metal dichalcogenides has been possible owing to their special structures and remarkable properties. In particular, palladium diselenide (PdSe2) with a novel pentagonal stru...
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The rapid development of two-dimensional (2D) transition-metal dichalcogenides has been possible owing to their special structures and remarkable properties. In particular, palladium diselenide (PdSe2) with a novel pentagonal structure and unique physical characteristics have recently attracted extensive research interest. Consequently, tremendous research progress has been achieved regarding the physics, chemistry, and electronics of PdSe2. Accordingly, in this review, we recapitulate and summarize the most recent research on PdSe2, including its structure, properties, synthesis, and applications. First, a mechanical exfoliation method to obtain PdSe2 nanosheets is introduced, and large-area synthesis strategies are explained with respect to chemical vapor deposition and metal selenization. Next, the electronic and optoelectronic properties of PdSe2 and related heterostructures, such as field-effect transistors, photodetectors, sensors, and thermoelectric devices, are discussed. Subsequently, the integration of systems into infrared image sensors on the basis of PdSe2 van der Waals heterostructures is explored. Finally, future opportunities are highlighted to serve as a general guide for physicists, chemists, materials scientists, and engineers. Therefore, this comprehensive review may shed light on the research conducted by the 2D material community.
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This paper investigates how industry peer firms influence the voluntary disclosure strategies of individual firms. Our 2SLS regressions on an empirical sample of management earnings forecasts show that the disclosure strategies of...
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This paper investigates how industry peer firms influence the voluntary disclosure strategies of individual firms. Our 2SLS regressions on an empirical sample of management earnings forecasts show that the disclosure strategies of individual firms are significantly influenced by their peer firms' disclosure behaviors. Specifically, the increased disclosure frequency and disclosure horizon of their industry peers encourage individual firms to increase their disclosure frequency and disclosure horizon. Moreover, firms with S&P credit ratings, higher profitability, larger size, and/or a higher market-to-book ratio tend to be more sensitive to their peer firms' voluntary disclosure frequency, and react more strongly to peer firms that are of dissimilar size or profitability. Finally, we find that the leader-follower relation does not influence the effects of peer firms' disclosure strategies. Additional tests suggest that signaling theory and litigation risk provide stronger explanations of why firms mimic their peers than herding theory and free rider theory. This paper contributes to the accounting literature by providing new evidence on the effects of voluntary disclosure. Our findings are also of relevance to industry practitioners, and they shed light on the recently proposed voluntary disclosure regulations.
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Brain signals refer to the biometric information collected from the human brain. The research on brain signals aims to discover the underlying neurological or physical status of the individuals by signal decoding. The emerging dee...
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Brain signals refer to the biometric information collected from the human brain. The research on brain signals aims to discover the underlying neurological or physical status of the individuals by signal decoding. The emerging deep learning techniques have improved the study of brain signals significantly in recent years. In this work, we first present a taxonomy of non-invasive brain signals and the basics of deep learning algorithms. Then, we provide the frontiers of applying deep learning for non-invasive brain signals analysis, by summarizing a large number of recent publications. Moreover, upon the deep learning-powered brain signal studies, we report the potential real-world applications which benefit not only disabled people but also normal individuals. Finally, we discuss the opening challenges and future directions.
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Recently, the newly-emerging lead-free metal-halide materials with less
toxicity and superior optoelectronic properties have received wide attention as
the safer and potentially more robust alternatives to lead-based perovskite
...
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Recently, the newly-emerging lead-free metal-halide materials with less
toxicity and superior optoelectronic properties have received wide attention as
the safer and potentially more robust alternatives to lead-based perovskite
counterparts. Among them, ternary copper halides (TCHs) have become a
vital group due to their unique features, including abundant structural
diversity, ease of synthesis, unprecedented optoelectronic properties, high
abundance, and low cost. Although the recent efforts in this field have made
certain progresses, some scientific and technological issues still remain
unresolved. Herein, a comprehensive and up-to-date overview of recent
progress on the fundamental characteristics of TCH materials and their
versatile applications is presented, which contains topics such as: i) crystal
and electronic structure features and synthesis strategies; ii) mechanisms of
self-trapped excitons, luminescence regulation, and environmental stability;
and iii) their burgeoning optoelectronic devices of phosphor-converted white
light-emitting diodes (WLEDs), electroluminescent LEDs, anti-counterfeiting,
X-ray scintillators, photodetectors, sensors, and memristors. Finally, the
current challenges together with future perspectives on the development of
TCH materials and applications are also critically described, which is
considered to be critical for accelerating the commercialization of these
rapidly evolving technologies.
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There has been a burgeoning Fintech literature in the past years, especially on cryptocurrencies. However, there is lack of research handling cryptocurrencies in a mainstream macroeconomic model. To bridge the gap, we develop a mo...
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There has been a burgeoning Fintech literature in the past years, especially on cryptocurrencies. However, there is lack of research handling cryptocurrencies in a mainstream macroeconomic model. To bridge the gap, we develop a model for Bitcoin-like cryptocurrency as risky and costly bubbles in an infinite-horizon production economy. This model is consistent with the following facts: (1) the surging Bitcoin market presents enormous volatility, (2) its price dynamics are significantly sensitive to both market sentiment and policy stances. Entrepreneurial firms choose to hold Bitcoins as liquid assets to buffer idiosyncratic investment distortions. The intrinsically worthless Bitcoins can emerge as rational bubbles when the market sentiment is optimistic enough. On the one hand, bubbly Bitcoins provide market liquidity to facilitate investment in the real sector, while on the other hand, they deteriorate the investment efficiency and crowd out aggregate production. Our quantitative exercise produces various cyclical features of Bitcoin bubbles and find that the collapse of Bitcoin bubbles can improve social welfare by decreasing distortion-driven real investment.
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