Sun Yat-sen University

About: Sun Yat-sen University is a education organization based out in Guangzhou, Guangdong, China. It is known for research contribution in the topics: Population & Cancer. The organization has 115149 authors who have published 113763 publications receiving 2286465 citations. The organization is also known as: Zhongshan University & SYSU.

A solid-state source of strongly entangled photon pairs with high brightness and indistinguishability.

Abstract: The generation of high-quality entangled photon pairs has been a long-sought goal in modern quantum communication and computation. So far, the most widely used entangled photon pairs have been generated from spontaneous parametric down-conversion (SPDC), a process that is intrinsically probabilistic and thus relegated to a regime of low rates of pair generation. In contrast, semiconductor quantum dots can generate triggered entangled photon pairs through a cascaded radiative decay process and do not suffer from any fundamental trade-off between source brightness and multi-pair generation. However, a source featuring simultaneously high photon extraction efficiency, high degree of entanglement fidelity and photon indistinguishability has been lacking. Here, we present an entangled photon pair source with high brightness and indistinguishability by deterministically embedding GaAs quantum dots in broadband photonic nanostructures that enable Purcell-enhanced emission. Our source produces entangled photon pairs with a pair collection probability of up to 0.65(4) (single-photon extraction efficiency of 0.85(3)), entanglement fidelity of 0.88(2), and indistinguishabilities of 0.901(3) and 0.903(3) (brackets indicate uncertainty on last digit). This immediately creates opportunities for advancing quantum photonic technologies.

Dual function of Arabidopsis ATAF1 in abiotic and biotic stress responses.

Abstract: NAC family genes encode plant-specific transcription factors involved in diverse biological processes. In this study, the Arabidopsis NAC gene ATAF1 was found to be induced by drought, high-salinity, abscisic acid (ABA), methyl jasmonate, mechanical wounding, and Botrytis cinerea infection. Significant induction of ATAF1 was found in an ABA-deficient mutant aba2 subjected to drought or high salinity, revealing an ABA-independent mechanism of expression. Arabidopsis ATAF1-overexpression lines displayed many altered phenotypes, including dwarfism and short primary roots. Furthermore, in vivo experiments indicate that ATAF1 is a bona fide regulator modulating plant responses to many abiotic stresses and necrotrophic-pathogen infection. Overexpression of ATAF1 in Arabidopsis increased plant sensitivity to ABA, salt, and oxidative stresses. Especially, ATAF1 overexpression plants, but not mutant lines, showed remarkably enhanced plant tolerance to drought. Additionally, ATAF1 overexpression enhanced plant susceptibility to the necrotrophic pathogen B. cinerea, but did not alter disease symptoms caused by avirulent or virulent strains of P. syringae pv tomato DC3000. Transgenic plants overexpressing ATAF1 were hypersensitive to oxidative stress, suggesting that reactive oxygen intermediates may be related to ATAF1-mediated signaling in response to both pathogen and abiotic stresses.

Iron-Based Supercapacitor Electrodes: Advances and Challenges

Abstract: Supercapacitors (SCs) have great promise as the state-of-the-art power source in portable electronics and hybrid vehicles. The performance of SCs is largely determined by the properties of the electrode material, and numerous efforts have been devoted to the explorations of novel electrode materials. Recently, iron-based materials, including Fe2O3, Fe3O4, FeOOH, FeOx, CoFe2O4, and MnFe2O4, have received considerable attention as very promising electrode materials for SCs due to their high theoretical specific capacitances, natural abundance, low cost, and non-toxicity. However, most of these Fe-based SC electrodes suffer from poor conductivity and/or electrochemical instability, which seriously impede their implementation as high-performance electrodes for SCs. To settle these issues, substantial efforts have been made in improving their conductivity and cycling stability, and great processes have been achieved. Here, recent research advances in the rational design and synthesis of diverse Fe-based nanostructured electrodes and their capacitive performance for SCs are presented. Besides, challenges and prospects of Fe-based materials as advanced negative electrodes for SCs are also discussed.

Addition of multiple limiting resources reduces grassland diversity

Abstract: Niche dimensionality provides a general theoretical explanation for biodiversity-more niches, defined by more limiting factors, allow for more ways that species can coexist. Because plant species compete for the same set of limiting resources, theory predicts that addition of a limiting resource eliminates potential trade-offs, reducing the number of species that can coexist. Multiple nutrient limitation of plant production is common and therefore fertilization may reduce diversity by reducing the number or dimensionality of belowground limiting factors. At the same time, nutrient addition, by increasing biomass, should ultimately shift competition from belowground nutrients towards a one-dimensional competitive trade-off for light. Here we show that plant species diversity decreased when a greater number of limiting nutrients were added across 45 grassland sites from a multi-continent experimental network. The number of added nutrients predicted diversity loss, even after controlling for effects of plant biomass, and even where biomass production was not nutrient-limited. We found that elevated resource supply reduced niche dimensionality and diversity and increased both productivity and compositional turnover. Our results point to the importance of understanding dimensionality in ecological systems that are undergoing diversity loss in response to multiple global change factors.