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AlN is a common buffer layer in GaN‐based light emitting diode (LED) devices. However, application of AlN on industry‐relevant patterned sapphire substrate (PSS) causes unwanted screw dislocations in the epitaxial layer during GaN nucleation. Industry experience suggests that AlON buffer layer improves the quality of GaN epitaxial layer, but the low‐dislocation‐defect epitaxy mechanisms remain unclear. Herein, high‐brightness GaN‐based blue LEDs with the sputtered AlON buffer layer on industry‐grade four‐inch PSS is demonstrated. The effect of oxygen addition to AlN is revealed by growing GaN epitaxial layers on AlON buffer layers with different oxygen contents and testing these GaN layers in LED devices. Compared with conventional AlN, our AlON buffer layer reduces the density of screw dislocations, thereby improving the quality of the GaN epitaxial layers and the performance of GaN‐based LEDs. These insights allow the explanation of the growth mechanisms of GaN on PSS with AlN and AlON buffer layers and can guide the development of next‐generation optoelectronic technologies. [ABSTRACT FROM AUTHOR]

Ga2O3 is a wide bandgap semiconductor suitable for solar‐blind photodetection, but there exist two issues for Ga2O3‐based photodetectors: first, it is difficult to achieve reliable p‐type Ga2O3 and therefore form a homojunction photodetector, and the other is related with the slow response speed of Ga2O3‐based photodetectors. In this work, a self‐powered solar‐blind photodetector with a fast response using a p‐GaN/i‐Ga2O3/n‐Ga2O3 (pin) heterojunction with a fully depleted active region is realized, where i‐Ga2O3 serves as the main light‐absorbing active region. The device exhibits good self‐powered characteristics with a high responsivity of 72 mA W−1, a high photo‐to‐dark current ratio of 18 800, a high specific detectivity of 3.22 × 1012 Jones, and a fast response speed with a rise time/decay time of 7 ms/19 ms, respectively, without an external power supply. A detailed study of the interfacial electronic structure between p‐GaN and i‐Ga2O3 reveals a conduction band offset and valence band offset of 0.16 and 1.37 eV, respectively. Meanwhile, it has a large built‐in potential of 1.03 eV and a wide depletion region width of 235 nm in the i‐Ga2O3 side of heterojunction. It is believed that excellent device performance comes from a suitable energy band structure and wide depletion region. [ABSTRACT FROM AUTHOR]

Early diagnosis, early treatment, and improved prognosis in patients with ischemic stroke are vital requirements. Current clinical practices for the diagnosis of stroke include computed tomography, magnetic resonance imaging, and other traditional imaging methods to quickly check the location, volume, etc, in the hospital; however, diagnosis of the underlying cause of infarction is not effective with these practices. Owing to the coexistence of various etiologies, accurate and timely diagnosis using routine hematology and biochemical tests remains a challenge. Exosomes are membrane vesicles, approximately 30–150 nm in diameter, which fuse with cell membrane and are released into the extracellular space. As one of the research hotspots in the field of medicine in recent years, exosomes can participate in immune response, antigen presentation, cell migration, tumor invasion, and so on. Owing to the important role played by the miRNAs contained in exosomes, the latter have shown great potential in the diagnosis and treatment of ischemic stroke. This article reviews the progress made regarding the exosomal miRNAs as ischemic stroke biomarkers. [ABSTRACT FROM AUTHOR]

We applied organic nanostructures based on thermally activated delayed fluorescent (TADF) emitters for singlet oxygen generation. Due to the extremely small energy gaps between the excited singlet states (S1) and triplet states (T1) of these heavy-metal-free organic nanostructures, intersystem conversion between S1 and T1 can occur easily. This strategy also works well for exciplex-type TADF emitters prepared by mixing suitable donors and acceptors which have no TADF characteristics themselves. [ABSTRACT FROM AUTHOR]

Graphene/silicon (Si) heterojunction photodetectors are widely studied in detecting of optical signals from near-infrared to visible light. However, the performance of graphene/Si photodetectors is limited by defects created in the growth process and surface recombination at the interface. Herein, a remote plasma-enhanced chemical vapor deposition is introduced to directly grow graphene nanowalls (GNWs) at a low power of 300 W, which can effectively improve the growth rate and reduce defects. Moreover, hafnium oxide (HfO2) with thicknesses ranging from 1 to 5 nm grown by atomic layer deposition has been employed as an interfacial layer for the GNWs/Si heterojunction photodetector. It is shown that the high-k dielectric layer of HfO2 acts as an electron-blocking and hole transport layer, which minimizes the recombination and reduces the dark current. At an optimized thickness of 3 nm HfO2, a low dark current of 3.85 × 10−10, with a responsivity of 0.19 AW−1, a specific detectivity of 1.38 × 1012 as well as an external quantum efficiency of 47.1% at zero bias, can be obtained for the fabricated GNWs/HfO2/Si photodetector. This work demonstrates a universal strategy to fabricate high-performance graphene/Si photodetectors. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, an nonlinear asymptotically periodic multispecies competition predator–prey system with general functional response is studied. And we obtain sufficient conditions for the uniformly strong persistence of the system. In particular, our result extend the result in [F.Y. Wei, K. Wang, Uniform persistence of asymptotically periodic multispecies competition predator–prey systems with Holling III type of functional response, Appl. Math. Comput., in press]. [Copyright &y& Elsevier]

Abstract: By using the continuation theorem of coincidence degree theory, we obtain a sufficient condition on the existence of positive periodic solutions of a delayed periodic predator–prey system with general functional response. [Copyright &y& Elsevier]

An upper bound Z(2,n) ≤ [n/2]+6[(n-1)/2]+5 is derived for the number of zeros of Abelian integrals Ĩ(h) = ∫γ(h)g(x, y)dx - f(x, y)dy on the open interval (0, 1/6), where λ(h) is an oval lying on the algebraic curve Hλ = (1/3)x3 + (1/2)x2 + λy3 + y2 + h, f(x, y), g(x, y) are polynomials of x and y, and n = max{deg f(x, y), deg g(x, y)}. The proof exploits that expansion of I&(tilde;h) near λ = 0. [ABSTRACT FROM AUTHOR]

In this paper, a one-parameter Hamiltonian system under cubic perturbations is investigated and the upper bound of the number of zeros of the Abelian integral is obtained by using Horozov and Iliev's method. [ABSTRACT FROM AUTHOR]

In this paper, we consider an N-species nonlinear prey–competition system. Using the differential inequality theorem and the V-function method, we obtain some sufficient conditions for the permanence and global asymptotic stability of the system. [Copyright &y& Elsevier]

The periodic Lotka–Volterra model with m-predators and n-preys is considered in this paper. Under the suppose that the intrinsic growth rate of the prey species may be negative while the total intrinsic growth rate in a period are positive, sufficient conditions are obtained for existence and global asymptotic stability of the periodic solution of this model. [Copyright &y& Elsevier]

Liver cancer is a cunning malignancy with a high incidence and mortality rate among cancers worldwide. The NPC gene family members (NPCs: NPC1, NPC2, and NPC1L1) are closely linked to the development of multiple cancers, but their role in liver cancer remains unclear. As a result, we must investigate their functions in liver hepatocellular carcinoma (LIHC). NPCs were significantly differentially expressed between normal and LIHC tissues, with a high mutation frequency in LIHC. The ROC curve analysis revealed that NPC1/NPC2 had high diagnostic and prognostic values in LIHC. NPC1 expression was also found to be negatively correlated with its methylation level. The differentially expressed genes between high and low NPC1 expression groups in LIHC were mainly related to channel activity, transporter complexes, and plasma membrane adhesion molecules. Additionally, NPC1 expression was significantly associated with multiple immune cells and immunization checkpoints. It was hypothesized that a TUG1/SNHG4-miR-148a-3p-NPC1 regulatory axis is associated with hepatocarcinogenesis. Finally, the protein expression of NPC1 in LIHC tissues and paraneoplastic tissues was detected, and NPC1-knockdown HepG2 cells (NPC1KO) inhibited the proliferation, migration, and invasion. This study helped to identify new prognostic markers and potential immunotherapeutic targets for LIHC and revealed the molecular mechanisms underlying NPC1 regulation in LIHC. The NPCs play a key role in the prognosis and diagnosis of LIHC and may be an important indicator for LIHC prognosis and diagnosis; NPC1 might be a potential therapeutic target in LIHC. [ABSTRACT FROM AUTHOR]

Taking shallow groundwater in Jinjiang city, Fujian Province for example, it was found that the classical element-matter analysis shows deficiency in calculation of correlation function, so the improved matter-element method was applied for the comprehensive assessment of shallow groundwater in Jinjiang City, and the spatial distribution was shown in maps. The assessment results demonstrated that ground water quality of most regions in the study area belonged to Glade I and II, thus the overall quality of shallow groundwater was good. The groundwater of Grade IV and V (relatively poor and extremely poor) was mainly distributed in Dongshi Town, Chendi Town, Zimao Town, and Shenhu Town, major exceeding-standard factors that influence shallow groundwater quality in the local area included TDS, Mn2+, NO3-, NO2-, NH4+ and Cl--, which mainly owed to invasion of seawater, original geological conditions, industrial and agricultural discharge, and human life. [ABSTRACT FROM AUTHOR]

This work reports the fabrication of high performance solar‐blind deep‐UV photodetectors using (InxGa1−x)2O3 thin films grown on Al2O3 (0001) substrates. The In contents in (InxGa1−x)2O3 are controlled at x = 0, 0.1 and 0.2, whereas a higher In content leads to phase segregation of Ga2O3 and In2O3. The bandgaps of (InxGa1−x)2O3 films are tuned from 4.93 eV for Ga2O3 to 4.67 eV for (In0.2Ga0.8)2O3. Schottky‐type photodetectors based on metal−semiconductor−metal structure were fabricated. The (In0.1Ga0.9)2O3 photodetector is highly sensitive to solar‐blind UV spectrum and achieves a large on/off current ratio of over 108, a remarkable specific detectivity of 4.5 × 1016 Jones with a prominent responsivity of 23.3 A W−1. Such enhanced performance compared to Ga2O3 is associated with In modulated optical and electronic properties. High‐resolution X‐ray photoemission spectroscopy was used to study the interfacial electronic structure at the semiconductor−metal interface. A large Schottky barrier height of 1.31 eV was found for (In0.1Ga0.9)2O3 devices, accounting for the low dark current. More importantly, the incorporation of In introduces In 4d states hybridizing with O 2p at top of the valence band of (In0.1Ga0.9)2O3, which increases the optical absorption to generate a higher density of photocarriers, and therefore results in greater photocurrents. [ABSTRACT FROM AUTHOR]

This paper deals with Liénard equations of the form &xdot;=y,&ydot;=P(x)+yQ(x,y), with P and Q polynomial of degree 5 and 4, respectively. Attention goes to perturbations of the Hamiltonian vector fields with an elliptic Hamiltonian of degree six, exhibiting a double figure eight-loop. It is proved that the Hopf cyclicity is two, and it is also given by the new configurations of the limit cycles bifurcated from the homoclinic loop or heteroclinic loop for quintic system with quintic perturbations by using the methods of bifurcation theory and qualitative analysis. [Copyright &y& Elsevier]

• miR-181d-5p expression was downregulated in PBMCs of LN patients and MRL/lpr mice. • miR-181d-5p can directly target binding to MAPK8. • Overexpression of miR-181d-5p inhibited the phosphorylation of p38 and p44/42 in the THP-1 cells. • Overexpression of miR-181d-5p elevated THP-1 cell viability and decreased the inflammatory response. • Overexpression of miR-181d-5p decreased antinuclear antibodies and fibrosis levels in MRL/lpr mice. Lupus nephritis (LN) is a common immune disease. The microRNA (miR)-181d-5p is a potential target for treating kidney injury. However, the therapeutic role of miR-181d-5p in LN has not been investigated. This study aimed to investigate the role of miR-181d-5p in targeting mitogen-activated protein kinase 8 (MAPK8) and stimulating the MAPK signaling pathway in LN. RT-qPCR was performed to identify the variations in miR-181d-5p expression in peripheral blood mononuclear cells (PBMCs) obtained from 42 LN patients, 30 healthy individuals, 6 MRL/lpr mice and 6 C57BL/6 mice. Western blot was used to detect the effect of miR-181d-5p on the MAPK signaling pathway in THP-1 cells and MRL/lpr mice. Enzyme-linked immunosorbent assay (ELISA) was utilized to detect the effect of miR-181d-5p on antinuclear antibodies and inflammatory factors. A dual-luciferase reporter assay was used to verify whether miR-181d-5p directly targets MAPK8. Flow cytometry was performed to evaluate apoptosis rates in transfected THP-1 cells. miR-181d-5p expression was downregulated in PBMCs of LN patients (P < 0.01) and MRL/lpr mice (P < 0.05). A dual luciferase reporter assay demonstrated that miR-181d-5p inhibits MAPK8 (P < 0.01). Overexpression of miR-181d-5p inhibited the phosphorylation of p38 (P < 0.001) and p44/42 (P < 0.01). Moreover, miR-181d-5p decreased the apoptosis rate of THP-1 cells (P < 0.001), and reduced the secretion of IL-6 (P < 0.01) and TNF-α (P < 0.01). Furthermore, overexpression of miR-181d-5p decreased anti-dsDNA antibody (P < 0.05), anti-Sm antibody (P < 0.01), and fibrosis levels in MRL/lpr mice. Upregulation of miR-181d-5p showed anti-inflammatory and anti-apoptotic effects on THP-1 cells in vitro and kidney injury in vivo. These effects were achieved by miR-181d-5p targeting MAPK8 to inhibit phosphorylation of p38 and p44/42. These results may offer new insights for improving therapeutic strategies against lupus nephritis. [ABSTRACT FROM AUTHOR]

In this study, a novel genotyping point-of-care testing (POCT) rapid detection device, the locked nucleic acid (LNA)-amplification refractory mutation system (ARMS)-recombinase polymerase amplification (RPA)-GoldMag lateral flow assay (LFA) platform, was provided by mining and synthesis based on prior technology. Research methods based on system-integrated innovation and knowledge-integrated generation have become a new trend in technology development. Here, we exploit the combination of LNA-coupled ARMS-RPA and gold nanoparticle probe technology for detection signal amplification, thus pioneering a new tool for accurate, rapid, and cost-effective genotyping. We also performed SNP typing detection and clinical validation of this new assay platform using common glucose-6-phosphate dehydrogenase (G6PD) gene single nucleotide polymorphism (SNP) loci, and the results demonstrated the high sensitivity, specificity, stability, accuracy and feasibility of the LNA-ARMS-RPA-GoldMag lateral flow assay platform. It is hoped that this new technology will make a significant contribution to the field of POCT rapid diagnosis and aim to expand the application space, reflecting its clinical application value and development prospects. • Constructed a genotyping POCT detection device: LNA-enhanced ARMS-RPA-GoldMag LFA platform. • Innovative combination of LNA, ARMS-RPA and GoldMag technology amplifies the detection signal. • SNP loci of the G6PD typing assay demonstrate the superiority and feasibility of the LARGL platform. [ABSTRACT FROM AUTHOR]

[Display omitted] • Plasma-enhanced thermal oxidation first-time applied for high-rate Ga 2 O 3 growth. • Ga 2 O 3 features low roughness and growth with preferential ( 2 ¯ 01) crystal plane. • Plasma-specific effects and surface defects define β-Ga 2 O 3 growth mechanism. • Photodetector has a high solar blind-to-UV rejection ratio and low response time. Almost all reported high-performance β-Ga 2 O 3 thin films are grown by molecular beam epitaxy, metal–organic chemical vapor deposition, and pulsed laser deposition at a very high cost and low throughput. To explore the fast growth method for β-Ga 2 O 3 with high quality and low cost, a custom-made plasma-enhanced chemical vapor deposition is designed for innovative thermal oxidation of gallium nitride. It is shown that the growth rate of gallium oxide thin films prepared by the plasma-enhanced thermal oxidation (PETO) is 2 to 5 times higher than that of thermal oxidation process under similar growth conditions. For β-Ga 2 O 3 thin films prepared by the PETO, the high-rate growth, low root-mean-square roughness, and growth with the orientation along ( 2 ¯ 01) lattice plane are achieved. The developed growth mechanism elucidates the role of the O 2 and Ar + O 2 plasma-surface interactions in the β-Ga 2 O 3 growth process. Solar-blind photodetectors based on the β-Ga 2 O 3 films grown by the PETO with a high solar blind-to-UV rejection ratio (R 245 nm /R 360 nm = 10.2), a low rise time of 0.17 s, and a low fall time of 0.2 s are demonstrated. The plasma-surface interaction effects are generic and are applicable to a broader range of materials systems and devices for diverse applications. [ABSTRACT FROM AUTHOR]

The charge generation process of hexaazatriphenylene hexacarbonitrile-based intermediate connectors (ICs) in blue tandem organic light-emitting diodes (OLEDs) is investigated via photoelectron spectroscopic and device studies. Though 1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile (HATCN) is well-known to be a p-type hole-injection layer, our photoelectron spectroscopic results indicate that HATCN becomes the n-type when it is sandwiched between Li-doped 4,7-diphenyl-1,10-phenanthroline (BPhen) and N,N″-diphenyl-N,N″-bis(1-naphthyl)-(1,1′-biphenyl)-4,4′-diamine (NPB) layers, and the charge generation and separation at the Li:BPhen/HATCN/NPB interfaces become energetically favorable, as depicted by their energy level alignments. This explains the superior device performance when Li:BPhen/HATCN/NPB is used as a connecting unit in tandem devices. • Different intermediate connectors were investigated via photoelectron spectroscopic and device studies. • Li-doped BPhen layer in the intermediate connector facilitates electron injection from HATCN to the ETL of adjacent EL unit. • Li-doped BPhen layer also blocks the leakage of holes across the intermediate connector to the HTL of the adjacent EL unit. [ABSTRACT FROM AUTHOR]

• NSCs derived exosomes inhibit the apoptosis while promoting the proliferation of neural cells both in vivo and in vitro. • miR-150-3p was the most abundantly expressed miRNA in exosomes compared to their parent NSCs. • NSC derived exosomes facilitate the neuroprotective effects via transfer of miR-150-3p which targets CASP2, thus suppressing neuronal apoptosis after brain injury. Brains are vulnerable to ischemic/hypoxic damage, which are directly caused by stroke, hypoxic-ischemic encephalopathy and other cerebral diseases. Currently, therapeutic strategies against cerebral ischemia and hypoxia are extremely limited. Recent studies have indicated that stem cell-derived exosomes play a neuroprotective role in hypoxic-ischemic brain injury. However, the treatment mechanism remains unclear. In this study, we cultured neural stem cells (NSCs) in vitro successfully. Exosomes isolated from NSCs (NSCs-Ex) inhibited the apoptosis while promoting the proliferation of SH-SY5Y cells both in normal and oxygen-glucose deprivation (OGD) culture conditions. Moreover, in vivo studies demonstrated that NSCs-Ex significantly reduced the infarction area in the middle cerebral artery occlusion (MCAO) model and suppressed the apoptosis of neurons. Furthermore, miR-150-3p was identified as the most abundantly expressed miRNA in exosomes compared to their parent NSCs. The miR-150-3p mimic displayed neuroprotective effects while miR-150-3p inhibitor exacerbated nerve injury both in vivo and in vitro. We further identified CASP2 as a miR-150-3p target. Thus, our data indicate that NSC-Ex facilitate the neuroprotective effects via transfer of miR-150-3p which targets CASP2, thus suppressing neuronal apoptosis after brain injury. Our results suggest that NSCs-Ex prevent cerebral injury by transferring miR-150-3p which promotes neurons proliferation by inhibiting CASP2 signaling pathway. [ABSTRACT FROM AUTHOR]

Multifunctional donor-acceptor compound 4,4′-bis(dibenzothiophene- S,S-dioxide-2-yl)triphenylamine ( DSTPA) was obtained by linking a strongly electron-withdrawing core and a strongly electron-donating core with a biphenyl bridge in linear spatial alignment. DSTPA not only has suitable HOMO and LUMO levels for easily accepting both holes and electrons, it was also demonstrated to have a high fluorescence quantum yield of 0.98 and a high triplet energy level of 2.39 eV. Versatile applications of DSTPA for bipolar transport, green fluorescent emission, and sensitizing a red phosphor were systematically investigated in a series of multi- and single-layer organic light-emitting devices. In traditional multilayer devices, it shows excellent performance both in an undoped fluorescent device (used as a green emitter and achieving maximum current and power efficiencies (CE and PE) of 12.6 cd A−1 and 9.4 Lm W−1, respectively) and in a red phosphorescent device (used as a host and achieving maximum CE and PE of 26.4 cd A−1 and 26.3 Lm W−1, respectively). Furthermore, DSTPA was also simultaneously used as an emitter, a hole transporter, and an electron transporter in a single-layer device showing CE and PE of 5.1 cd A−1 and 4.7 Lm W−1, respectively. A single-layer red phosphorescent device with efficiencies of 11.7 cd A−1 and 12.6 Lm W−1 was obtained by doping DSTPA with a red phosphor. The performances of all of the devices in this work are comparable to the best of their corresponding classes in the literature. [ABSTRACT FROM AUTHOR]