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A high-quality β-Ga2O3 film was grown on a (111) GaAs substrate using the metal organic chemical vapor deposition method. The band alignment of the β-Ga2O3/GaAs heterojunction interface was determined by x-ray photoelectron spectroscopy. The energy-band structure of β-Ga2O3/GaAs was constructed based on the binding energies of Ga 3d and As 3d core levels as well as valence band maximum values. The valence band offset was determined to be 3.50 ± 0.05 eV. As a consequence, a type-ΙΙ heterojunction with a conduction band offset of 0.12 ± 0.05 eV was determined in the present study. The accurate determination of the band alignment of the β-Ga2O3/GaAs heterojunction provided useful information for the application in β-Ga2O3/GaAs-based devices. [ABSTRACT FROM AUTHOR]

Proteins of the alkylation B (AlkB) superfamily show RNA demethylase activity removing methyl adducts from N6‐methyladenosine (m6A). m6A is a reversible epigenetic mark of RNA that regulates human virus replication but has unclear roles in plant virus infection. We focused on Potyvirus—the largest genus of plant RNA viruses—and report here the identification of AlkB domains within P1 of endive necrotic mosaic virus (ENMV) and an additional virus of a putative novel species within Potyvirus. We show that Nicotiana benthamiana m6A levels are reduced by infection of plum pox virus (PPV) and potato virus Y (PVY). The two potyviruses lack AlkB and the results suggest a general involvement of RNA methylation in potyvirus infection and evolution. Methylated RNA immunoprecipitation sequencing of virus‐infected samples showed that m6A peaks are enriched in plant transcript 3′ untranslated regions and in discrete internal and 3′ terminal regions of PPV and PVY genomes. Down‐regulation of N. benthamiana AlkB homologues of the plant‐specific ALKBH9 clade caused a significant decrease in PPV and PVY accumulation. In summary, our study provides evolutionary and experimental evidence that supports the m6A implication and the proviral roles of AlkB homologues in Potyvirus infection. [ABSTRACT FROM AUTHOR]

Nitrogen (N) doping engineering is considered a promising approach to achieve p-type conductivity of Ga2O3 films. However, the defect self-compensation effect has been a major obstacle in this field. In this work, we propose a straightforward and environmentally friendly strategy to obtain a doped surface on β-Ga2O3 films via nonthermal N plasma-based treatment. By substituting nitrogen with oxygen, acceptor impurity levels are formed near the valence band, and self-trapped exciton recombination occurs, thereby enhancing the luminescence effect related to acceptor defects. Meanwhile, although achieving stable p-type conduction with N dopant acceptors remains challenging, the surface conductive properties are enhanced by the defect compensation of oxygen vacancy (VO) donor defects. Therefore, detailed investigations into the surface defect compensation of N-doped Ga2O3 thin films are of great research potential for device applications. [ABSTRACT FROM AUTHOR]

Doping technology with stable carrier concentration regulation is a guarantee for optimizing β -Ga 2 O 3 -based high-power electronic devices and optoelectronic devices. In this study, β -Ga 2 O 3 homoepitaxial epitaxial films with stable and tunable electron concentrations were grown on Fe-doped (010)-oriented β -Ga 2 O 3 substrates by using metal-organic chemical vapor deposition (MOCVD). XRD shows that the basic bulk properties of β -Ga 2 O 3 film, i. e. the structure and crystal orientation, are stable with low Si-doping, however, its electrical properties vary remarkably depending on concentrations of Si ions incorporated by Si source flow rate during the film growth process. Hall measurement is utilized to confirm high-quality β -Ga 2 O 3 films with tunable electron concentration of 1017–1019 cm−3. As a consequence, the electron concentration-dependent behavior of β -Ga 2 O 3 Schottky barrier diodes (SBDs) was studied. The β -Ga 2 O 3 SBDs exhibited better forward current output electrical performance with reduction in built-in potential difference (V bi) from 2.4 V to 0.3 V and on-resistance (R on) from 257 Ω cm to 26 Ω cm. Our results suggest that stable and tunable electron concentration provides high-quality material assurance for constructing power electronic devices of Ga 2 O 3. • We achieved high-quality β -Ga 2 O 3 films with tunable electron concentrations of 1017–1019 cm−3 by using MOCVD. • We constructed high-performance lateral β -Ga 2 O 3 SBDs with tunable electronic properties. • The doped films exhibit good forward current output characteristics and a relatively fast current growth rate. [ABSTRACT FROM AUTHOR]

A new barium aluminoborate, Ba 6 Al 4 B 14 O 33 , has been synthesized by the high-temperature solution reaction at 700 °C. The single-crystal XRD analysis showed that it crystallizes in a new structure type with space group P 1 ¯ , a =7.0070(14) Å, b =13.880(3) Å, c =14.702(3) Å, α= 86.48(3)°, β= 88.99(3)°, γ= 83.46(3)°, V =1417.8(5) Å 3 , and Z =2. The fundamental building blocks in this structure are AlO 4 tetrahedra, BO 3 triangles, [Al 4 O 14 ] 16− groups composed of two AlO 4 tetrahedra and two AlO 5 trigonal bipyramids, [B 6 O 14 ] 10− groups formed by one BO 3 triangle bonded to one [B 5 O 12 ] 9− double ring, and [B 6 O 13 ] 8− groups consisting of one BO 3 triangle linked to one [B 5 O 11 ] 7− double ring. They are held together via common O atoms to form a 3D network, with intersecting open channels accommodating Ba 2+ cations. The existence of both BO 3 and BO 4 groups is confirmed by FT-IR spectrum and an optical band gap of 3.44 eV is obtained from UV–VIS diffuse reflectance spectrum. Solid-state fluorescence spectrum has also been studied exhibiting the maximum emission peak at around 527 nm. Band structure calculations by the density functional theory method indicate that it is a direct band-gap insulator. [ABSTRACT FROM AUTHOR]

The influences of low growth temperatures (420–490 °C) on phase transition of Ga 2 O 3 films grown on Al 2 O 3 substrates by means of metal-organic chemical vapor deposition (MOCVD) are investigated here. The changes of crystal structure, phase composition, surface and cross-sectional morphologies are carried out by X-ray diffraction, atomic force microscope and field-emission scanning electron microscope to reveal the detail evolution from ε -phase to β -phase in Ga 2 O 3 films. The fluctuant Gibbs free energy change relying on growth temperature induces different growth mechanism of Ga 2 O 3 films. Furthermore, the ultraviolet photoresponse properties of different phase compositions for Ga 2 O 3 films are compared by constructing metal-semiconductor-metal photodetectors. It is found that mixture phase Ga 2 O 3 films express better photodetection performance than pure phase Ga 2 O 3 films due to the formation of built-in field within phase junction. This proposed regulation principle of Ga 2 O 3 phase transition provides a new route to high-performance photoelectric material. • Phase transition from ε -Ga 2 O 3 to β -Ga 2 O 3 was captured in a low growth temperature window of 420–490 °C by MOCVD. • Different Ga 2 O 3 phase compositions resulted in varying crystal structures, surface morphologies and UV sensing properties. • Ga 2 O 3 films with mixture phases demonstrated better photoresponse due to the formation of built-in field within phase junction. [ABSTRACT FROM AUTHOR]

• A β-Ga 2 O 3 /CuBiI 4 heterojunction deep-ultraviolet photodetector was constructed. • The fabricated device exhibited responsivity of 20.68 A/W and detectivity of 3.72 × 1015 Jones. • The detector could display self-powered operation. Herein, a β-Ga 2 O 3 /CuBiI 4 heterojunction deep-ultraviolet (DUV) photodetector was constructed based on metal-organic chemical vapor deposition grown β-Ga 2 O 3 film and spin-coated CuBiI 4 film. In which, we prepared the pure and well-crystallized CuBiI 4 film from environment-friendly materials under optimized experimental conditions. The fabricated device exhibited a large responsivity of 20.68 A/W, a high specific detectivity of 3.72 × 1015 Jones, a high photo-to-dark current ratio of 5.62 × 106, a low dark current of 0.385 pA, and an ultrahigh UV/visible rejection ratio (R 250 nm / R 400 nm) of 1.14 × 104 under 254 nm UV light illumination at 5 V. In all, the device can sensitively monitor a wide range of UV light (254 nm) intensities from 0.1 to 2000 μW/cm2. Moreover, the potential of the device operating under self-powered mode has been verified, and the intrinsic physical mechanism of the heterojunction photodetector was analyzed via energy-band alignment. Overall, this work would present a promising route to realize high-performance and cost-effective DUV photodetector. [ABSTRACT FROM AUTHOR]

• Solution processed VOx films obtain changeable conductivities in 2 orders of magnitude range. • Regulable conductivity of VO x enables effective hole-transport engineering in VO x /Ga 2 O 3 heterojunction. • Optimized VO x /Ga 2 O 3 photodetector demonstrates enhanced self-powered ultraviolet photodetection performance. The self-powered photodetection performance of the VO x /Ga 2 O 3 heterojunction photodetector could be effectively and positively regulated via the VO x hole transport layer by charge-carrier engineering, inducing the record PDCR of 1.08 × 108 and superhigh on/off ratio of 1.23 × 106. [Display omitted] As the carrier behavior is crucial to the photoelectric conversion process, the charge-carrier engineering could provide feasible strategy for high-performance photodetector (PD). Herein, self-powered ultraviolet PDs were constructed on VO x /Ga 2 O 3 (VGO) heterojunctions by adopting the solution processed VO x films as hole transport layer (HTL). Treated with different annealing ambients, the HTL demonstrated changeable conductivities due to the regulated crystallinities, phase structures and chemical valences, which further exerted influences on the VGO PDs inducing controllable photodetection properties. With effective hole transportation, low valence band barrier and large built-in field, the modulated VGO PDs achieved enhanced self-powered photodetection performance with photo-to-dark current ratio of 1.08 × 108, on/off ratio of 1.23 × 106, rejection ration (R 245 / R 400) of 3.12 × 104, responsivity of 28.9 mA/W and detectivity of 1.13 × 1014 Jones as well as rise/decay time of 57/74 ms. In consideration of the carrier-transport problems are commonly ubiquitous and particularly vital, our proposed HTL engineering method could open the high-performance route for self-powered ultraviolet PDs. [ABSTRACT FROM AUTHOR]

Simple Summary: N6-methyladenosine (m6A) is the most prevalent modification in the mRNAs of many eukaryotic species. The abundance and effects of m6A are determined by dynamic interactions between its methyltransferases ("writers"), demethylases ("erasers"), and binding proteins ("readers"). It has been indicated that there is a strong correlation between m6A and virus infection in mammals. In the case of plant virus infection, it appears that m6A plays a dual role. On the one hand, m6A acts as a plant immune response induced by virus infection, inhibiting viral replication or translation through methylation of viral genome RNAs. On the other hand, m6A acts as part of an infection strategy employed by plant viruses to overcome the host immune system by interacting with m6A-related proteins. We proposed that antagonists of m6A-related proteins might be used to design new strategies for plant virus control in the future. In recent years, m6A RNA methylation has attracted broad interest and is becoming a hot research topic. It has been demonstrated that there is a strong association between m6A and viral infection in the human system. The life cycles of plant RNA viruses are often coordinated with the mechanisms of their RNA modification. Here, we reviewed recent advances in m6A methylation in plant viruses. It appears that m6A methylation plays a dual role during viral infection in plants. On the one hand, m6A methylation acts as an antiviral immune response induced by virus infection, which inhibits viral replication or translation through the methylation of viral genome RNAs. On the other hand, plant viruses could disrupt the m6A methylation through interacting with the key proteins of the m6A pathway to avoid modification. Those plant viruses containing ALKB domain are discussed as well. Based on this mechanism, we propose that new strategies for plant virus control could be designed with competitive antagonists of m6A-associated proteins. [ABSTRACT FROM AUTHOR]

Gallium oxide (Ga2O3) is a representative of ultra-wide bandgap semiconductors, with a band gap of about 4.9 eV. In addition to a large dielectric constant and excellent physical and chemical stability, Ga2O3 has a theoretical breakdown electric field strength of more than 8 MV cmâˆ'1, which is 27 times more than that of Si and about twice as large as that of SiC and GaN. It is guaranteed that Ga2O3 has irreplaceable applications in ultra-high-power (1â€"10 kW) electronic devices. Unfortunately, due to the difficulty of p-type doping of Ga2O3, the full Ga2O3-based bipolar devices face more difficulties, and the unipolar Ga2O3 power Schottky diodes are feasible, but substantial progress has been made in recent years. In this article, we review the advanced progress and important achievements of the state-of-the-art Ga2O3-based power Schottky barrier diodes, and provide staged guidance for the further development of Ga2O3 power devices. Multiple types of device architectures, including basic structure, edge terminal processing, field-plated, trench and heterojunction pâ€"n structure, will be discussed in detail. [ABSTRACT FROM AUTHOR]

Fusarium wilt of potato is one of the most common diseases of potato in China, and is becoming a serious threat in potato production. It has been reported that osthole from Cnidium monnieri (L.) Cusson can inhibit plant pathogens. Here, we test the anti-fungal activity of C. monnieri osthole against Fusarium oxysporum in potatoes. The results showed that at a concentration of 5 mg/mL, osthole was able to obviously inhibit mycelial growth of F. oxysporum. We found that osthole caused changes of mycelial morphology, notably hyphal swelling and darkening. Osthole significantly reduced the spore germination of Fusarium by 57.40%. In addition, osthole also inhibited the growth of other pathogens such as Fusarium moniliforme J. Sheld, Thanatephorus cucumeris Donk, and Alternaria alternata (Fr.) Keissl, but not Alternaria solani Jonesetgrout and Valsa mali Miyabe and G. Yamada. Our results suggest that osthole has considerable potential as an agent for the prevention and treatment of potato Fusarium wilt. [ABSTRACT FROM AUTHOR]