How does exosome cause diabetes?

Exosomes are extracellular vesicles that are widely distributed in multiple cell types and circulating body fluids. They have a specific effect on the target cells by releasing different vesicle contents. They have recently been recognized as important means of intercellular communication, being involved, for example, in the development of diabetes by increasing ß-cell apoptosis, activating autoimmunity, and regulating cytokines to affect islet ß-cell function and insulin sensitivity. An in-depth study of the role of exosome in the pathogenesis of diabetes may therefore provide a novel means of diagnosing and treating diabetes. In this review, we detail how exosome is involved in the development of diabetes.

Exact mobility edges in quasiperiodic systems without self-duality.

Mobility edge (ME), a critical energy separating localized and extended states in spectrum, is a central concept in understanding localization physics. However, there are few models with exact MEs, and their presences are fragile against perturbations. In the paper, we generalize the Aubry-André-Harper model proposed in (Ganeshanet al2015Phys. Rev. Lett.114146601) and recently realized in (Anet al2021Phys. Rev. Lett.126040603), by introducing a relative phase in the quasiperiodic potential. Applying Avila's global theory, we analytically compute localization lengths of all single-particle states and determine the exact expression of ME, which both significantly depend on the relative phase. They are verified by numerical simulations, and physical perception of the exact expression is also provided. We show that old exact MEs, guaranteed by the delicate self-duality which is broken by the relative phase, are special ones in a series controlled by the phase. Furthermore, we demonstrate that out of expectation, exact MEs are invariant against a shift in the quasiperiodic potential, although the shift changes the spectrum and localization properties. Finally, we show that the exact ME is related to the one in the dual model which has long-range hoppings.

Entanglement entropy of non-Hermitian free fermions.

We study the entanglement properties of non-Hermitian free fermionic models with translation symmetry using the correlation matrix technique. Our results show that the entanglement entropy has a logarithmic correction to the area law in both one-dimensional and two-dimensional systems. For any one-dimensional one-band system, we prove that each Fermi point of the system contributes exactly 1/2 to the coefficientcof the logarithmic correction. Moreover, this relation betweencand Fermi point is verified for more general one-dimensional and two-dimensional cases by numerical calculations and finite-size scaling analysis. In addition, we also study the single-particle and density-density correlation functions.

Advances in Perovskite Light-Emitting Diodes Possessing Improved Lifetime.

Recently, perovskite light-emitting diodes (PeLEDs) are seeing an increasing academic and industrial interest with a potential for a broad range of technologies including display, lighting, and signaling. The maximum external quantum efficiency of PeLEDs can overtake 20% nowadays, however, the lifetime of PeLEDs is still far from the demand of practical applications. In this review, state-of-the-art concepts to improve the lifetime of PeLEDs are comprehensively summarized from the perspective of the design of perovskite emitting materials, the innovation of device engineering, the manipulation of optical effects, and the introduction of advanced encapsulations. First, the fundamental concepts determining the lifetime of PeLEDs are presented. Then, the strategies to improve the lifetime of both organic-inorganic hybrid and all-inorganic PeLEDs are highlighted. Particularly, the approaches to manage optical effects and encapsulations for the improved lifetime, which are negligibly studied in PeLEDs, are discussed based on the related concepts of organic LEDs and Cd-based quantum-dot LEDs, which is beneficial to insightfully understand the lifetime of PeLEDs. At last, the challenges and opportunities to further enhance the lifetime of PeLEDs are introduced.

Recent Developments in Tandem White Organic Light-Emitting Diodes.

Tandem white organic light-emitting diodes (WOLEDs) are promising for the lighting and displays field since their current efficiency, external quantum efficiency and lifetime can be strikingly enhanced compared with single-unit devices. In this invited review, we have firstly described fundamental concepts of tandem device architectures and their use in WOLEDs. Then, we have summarized the state-of-the-art strategies to achieve high-performance tandem WOLEDs in recent years. Specifically, we have highlighted the developments in the four types of tandem WOLEDs (i.e., tandem fluorescent WOLEDs, tandem phosphorescent WOLEDs, tandem thermally activated delayed fluorescent WOLEDs, and tandem hybrid WOLEDs). Furthermore, we have introduced doping-free tandem WOLEDs. In the end, we have given an outlook for the future development of tandem WOLEDs.

Strong Light-Matter Interactions in Single Open Plasmonic Nanocavities at the Quantum Optics Limit.

Reaching the quantum optics limit of strong light-matter interactions between a single exciton and a plasmon mode is highly desirable, because it opens up possibilities to explore room-temperature quantum devices operating at the single-photon level. However, two challenges severely hinder the realization of this limit: the integration of single-exciton emitters with plasmonic nanostructures and making the coupling strength at the single-exciton level overcome the large damping of the plasmon mode. Here, we demonstrate that these two hindrances can be overcome by attaching individual J aggregates to single cuboid Au@Ag nanorods. In such hybrid nanosystems, both the ultrasmall mode volume of ∼71 nm^{3} and the ultrashort interaction distance of less than 0.9 nm make the coupling coefficient between a single J-aggregate exciton and the cuboid nanorod as high as ∼41.6 meV, enabling strong light-matter interactions to be achieved at the quantum optics limit in single open plasmonic nanocavities.

Canine distemper virus isolated from a monkey efficiently replicates on Vero cells expressing non-human primate SLAM receptors but not human SLAM receptor.

BACKGROUND: In 2008, an outbreak of canine distemper virus (CDV) infection in monkeys was reported in China. We isolated CDV strain (subsequently named Monkey-BJ01-DV) from lung tissue obtained from a rhesus monkey that died in this outbreak. We evaluated the ability of this virus on Vero cells expressing SLAM receptors from dog, monkey and human origin, and analyzed the H gene of Monkey-BJ01-DV with other strains. RESULTS: The Monkey-BJ01-DV isolate replicated to the highest titer on Vero cells expressing dog-origin SLAM (10(5.2±0.2) TCID50/ml) and monkey-origin SLAM (10(5.4±0.1) TCID50/ml), but achieved markedly lower titers on human-origin SLAM cells (10(3.3±0.3) TCID50/ml). Phylogenetic analysis of the full-length H gene showed that Monkey-BJ01-DV was highly related to other CDV strains obtained during recent CDV epidemics among species of the Canidae family in China, and these Monkey strains CDV (Monkey-BJ01-DV, CYN07-dV, Monkey-KM-01) possessed a number of amino acid specific substitutions (E276V, Q392R, D435Y and I542F) compared to the H protein of CDV epidemic in other animals at the same period. CONCLUSIONS: Our results suggested that the monkey origin-CDV-H protein could possess specific substitutions to adapt to the new host. Monkey-BJ01-DV can efficiently use monkey- and dog-origin SLAM to infect and replicate in host cells, but further adaptation may be required for efficient replication in host cells expressing the human SLAM receptor.

Fatal canine distemper virus infection of giant pandas in China.

We report an outbreak of canine distemper virus (CDV) infection among endangered giant pandas (Ailuropoda melanoleuca). Five of six CDV infected giant pandas died. The surviving giant panda was previously vaccinated against CDV. Genomic sequencing of CDV isolated from one of the infected pandas (giant panda/SX/2014) suggests it belongs to the Asia-1 cluster. The hemagglutinin protein of the isolated virus and virus sequenced from lung samples originating from deceased giant pandas all possessed the substitutions V26M, T213A, K281R, S300N, P340Q, and Y549H. The presence of the Y549H substitution is notable as it is found at the signaling lymphocytic activation molecule (SLAM) receptor-binding site and has been implicated in the emergence of highly pathogenic CDV and host switching. These findings demonstrate that giant pandas are susceptible to CDV and suggest that surveillance and vaccination among all captive giant pandas are warranted to support conservation efforts for this endangered species.

Strong anisotropic lifetime orientation distributions of a two-level quantum emitter around a plasmonic nanorod.

Spontaneous emission lifetime orientation distributions of a two-level quantum emitter in metallic nanorod structures are theoretically investigated by the rigorous electromagnetic Green function method. It was found that spontaneous emission lifetime strongly depended on the transition dipole orientation and the position of the emitter. The anisotropic factor defined as the ratio between the maximum and minimum values of the lifetimes along different dipole orientations can reach up to 10(3). It is much larger than those in dielectric structures which are only several times usually. Our results show that the localized plasmonic resonance effect provides a new degree of freedom to effectively control spontaneous emission by the dipole orientation of the quantum emitters.

Vacuum Rabi splitting in a coupled system of single quantum dot and photonic crystal cavity: effect of local and propagation Green's functions.

We investigate the light emission characteristics for single two level quantum dot (QD) in a realistic photonic crystal (PC) L3 cavity based upon the local coupling strength between the QD and cavity together with the Green's function in which the propagation function related to the position of the detector is taken into account. We find for a PC cavity that the line shape of the propagation function in frequency domain is identical to that of the cavity and independent on the detector's position. We confirm that this identity is not influenced by the horizontal decay of the cavity. Furthermore, it is revealed that the vacuum fluorescence spectrum of the coupled system never give the triplet in strong coupling regime. Our work demonstrates that the experimental spectral-triplet in coupled system of single QD and PC cavity cannot be individually understood by vacuum Rabi splitting without including other physics mechanism.

Identification and characterization of porcine kobuvirus variant isolated from suckling piglet in Gansu province, China.

Kobuviruses comprise three species, the Aichivirus A, Aichivirus B, and Aichivirus C (porcine kobuvirus). Porcine kobuvirus is endemic to pig farms and is not restricted geographically but, rather, is distributed worldwide. The complete genomic sequences of four porcine kobuvirus strains isolated during a diarrhea outbreak in piglets in the Gansu province of China were determined. Two of these strains exhibited variations relative to the traditional strains. The potential 3C/3D cleavage sites of the variant strains were Q/C, which differed from the Q/S in the traditional porcine kobuvirus genome. A 90-nucleotide deletion in the 2B protein and a single nucleotide insertion in the 3'UTR were found in the variant strains. The VP1 regions of all four porcine kobuviruses in our study were highly variable (81%-86%). Ten common amino acid mutations were found specifically at certain positions within the VP1 region. Significant recombination sites were identified using SimPlot scans of whole genome sequences. Porcine kobuviruses were also detected in pig serum, indicating that the virus can escape the gastrointestinal tract and travel to the circulatory system. These findings suggest that mutations and recombination events may have contributed to the high level of genetic diversity of porcine kobuviruses and serve as a driving force in its evolution.

Plasmon-mediated resonance energy transfer by metallic nanorods.

We investigate the enhancement of the resonance energy transfer rate between donor and acceptor associated by the surface plasmons of the Ag nanorods on a SiO2 substrate. Our results for a single nanorod with different cross sections reveal that the cylinder nanorod has the strongest ability to enhance the resonance energy transfer rate. Moreover, for donor and acceptor with nonparallel polarization directions, we propose simple V-shaped nanorod structures which lead to the remarkable resonance energy transfer enhancement that is ten times larger than that by the single nanorod structure. We demonstrate that these structures have good robustness and controllability. Our work provides a way to improve the resonance energy transfer efficiency in integrated photonic devices. PACS: 78.67.Qa, 73.20.Mf, 42.50.Ex.

Slab thickness tuning approach for solid-state strong coupling between photonic crystal slab nanocavity and a quantum dot.

The quality factor and mode volume of a nanocavity play pivotal roles in realizing the strong coupling interaction between the nanocavity mode and a quantum dot. We present an extremely simple method to obtain the mode volume and investigate the effect of the slab thickness on the quality factor and mode volume of photonic crystal slab nanocavities. We reveal that the mode volume is approximatively proportional to the slab thickness. As compared with the previous structure finely optimized by introducing displacement of the air holes, via tuning the slab thickness, the quality factor can be enhanced by about 22%, and the ratio between the coupling coefficient and the nanocavity decay rate can be enhanced by about 13%. This can remarkably enhance the capability of the photonic crystal slab nanocavity for realizing the strong coupling interaction. The slab thickness tuning approach is feasible and significant for the experimental fabrication of the solid-state nanocavities.