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We realized the control on the crystal structure of GaAs nanowires (NWs) by silicon (Si) doping and V/III ratio. This viewpoint has been clearly evidenced by Raman spectrum combined with high-resolution transmission electron microscopy (HRTEM). Undoped GaAs NWs generally show a mixture of zinc blende (ZB) and wurtzite (WZ) phases; the addition of Si dopant and high V/III ratio are beneficial for the nucleation of ZB structure. Field effect transistor (FET) devices were fabricated to show that Si-doped GaAs NWs exhibit p-type conductivity in the low V/III ratio of 25.8 and n-type conductivity in the high V/III ratio of 51.6. These results provide a clear route for achieving GaAs NWs phase control and different conductivity types, which is an essential step towards the fabrication of nanoscale devices. • Phase control, formation of p-type and n-type GaAs NWs were designed and fabricated by Si doping and V/III ratio using MBE. • The doping-induced phase control from WZ/ZB mixed phase to the pseudo-pure phase ZB structure in the GaAs NWs were clearly revealed. • Si-doped GaAs NWs exhibit p-type and n-type conductivity with different V/III ratios were determined by FET. [ABSTRACT FROM AUTHOR]

Rationale: Primary cardiac angiosarcomas (PCA) is a rare malignancy with a poor prognosis. Currently, there is no standard treatment protocol for the PCA. We report a case of PCA in a 51-year-old woman., Patient Concerns: A 51-year-old woman initially presented with unexplained palpitations and chest tightness accompanied by nausea and vomiting, which worsened after activity and improved after rest. After symptomatic treatment, the symptoms improved, and the above symptoms recurred 8 months later., Diagnoses: Positron emission tomography-computed tomography revealed multiple lung nodules of varying sizes, some of which exhibited increased glucose metabolism. Furthermore, a soft tissue mass protruding into the pericardial cavity and involving the adjacent right atrium was observed in the right pericardium. The mass exhibited increased glucose metabolism, suggestive of a pericardial tumor with multiple lung metastases. Finally, histopathologic diagnosis of metastatic angiosarcoma was done by computed tomography-guided percutaneous lung and mediastinal biopsy., Interventions: The patient was treated with palliative chemotherapy for the primary cardiac angiosarcomas and hematogenous lung metastasis. One cycle later, the result of Next-Generation Sequencing showed that the microsatellite instability status was determined to be low-level. Based on this result, tislelizumab was added to the original chemotherapy regimen., Outcomes: Unfortunately, the patient with PCA passed away after only 2 cycles of chemotherapy, and the cause of death remained unknown., Lessons: This case report well demonstrates typical imaging findings of a rare cardiac angiosarcomas and emphasizes importance of early investigation for accurate diagnosis and proper management of the cardiac angiosarcomas., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2023 the Author(s). Published by Wolters Kluwer Health, Inc.)

Haploinsufficient mutation in arginine and glutamine-rich protein 1 (Arglu1), a newly identified pre-mRNA splicing regulator, may be linked to neural developmental disorders associated with mental retardation and epilepsy in human patients, but the underlying causes remain elusive. Here we show that ablation of Arglu1 promotes radial glial cell (RG) detachment from the ventricular zone (VZ), leading to ectopic localized RGs in the mouse embryonic cortex. Although they remain proliferative, ectopic progenitors, as well as progenitors in the VZ, exhibit prolonged mitosis, p53 upregulation and cell apoptosis, leading to reduced neuron production, neuronal loss and microcephaly. RNA seq analysis reveals widespread changes in alternative splicing in the mutant mouse embryonic cortex, preferentially affecting genes involved in neuronal functions. Mdm2 and Mdm4 are found to be alternatively spliced at the exon 3 and exon 5 respectively, leading to absence of the p53-binding domain and nonsense-mediated mRNA decay (NMD) and thus relieve inhibition of p53. Removal of p53 largely rescues the microcephaly caused by deletion of Arglu1. Our findings provide mechanistic insights into cortical malformations of human patients with Arglu1 haploinsufficient mutation., (© 2023. The Author(s).)

Perovskite materials with excellent optical and electronic properties have huge potential in the research field of photodetectors. Constructing heterojunctions and promoting carrier transportation are significant for the development of perovskite-based optoelectronics devices with high performances. Herein, we demonstrated a CsPbBr 3 /SnO 2 heterojunction photodetector and improved the device performances through post-annealing treatment of SnO 2 film. The results indicated that the electrical properties of SnO 2 films will make an important impact on carrier extraction, especially for type-II heterojunction. As the electrons transfer layer in CsPbBr 3 /SnO 2 type-II heterojunction, defects related to oxygen vacancy should be the key factor to affect carrier concentration, induce carriers' limitation and recombination rate. Under proper annealing temperature for SnO 2 layer, the recombination rate can decrease to 1.37 × 10 21 cm 3 s and the spectral responsivity will be highly increased. This work can enhance the understanding on the photoresponse of perovskite photodetectors, and will be helpful for the further optimization and design of optoelectronic devices based on the perovskite heterojunction., (© 2023 IOP Publishing Ltd.)

The band gap of lateral heterojunctions (LHSs) can be continuously tuned by changing the widths of their components. In this work, Sb/Bi LHSs based on monolayer Sb and Bi atoms with armchair and zigzag interfaces are constructed, respectively. It exhibits an atom's number in planner-dependent tunable band gap and near-infrared range absorption characteristics. They are systematically studied by first-principles calculations. The widths are represented by the number (n) of Sb or Bi atom chains. When n increases from 2 to 8, the bandgaps of armchair Sb n /Bi n LHSs decrease from 0.89 to 0.67 eV, and the band gaps of zigzag Sb n /Bi n LHSs decrease from 0.92 to 0.76 eV. The partial density of states spectra indicate that the occupied states of the valence band are mainly provided by the Bi 6 p orbitals. Additionally, the unoccupied states of the conduction band are always provided by the Sb 5 p orbitals and Bi 6 p orbitals. For Sb n /Bi n LHSs, the absorption edge along XX and YY directions move toward the long wavelength direction. These results provide an approach for the applications of two-dimensional materials in near-infrared devices., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhan, Fang, Wang, Fang, Li, Li and Wang.)

In recent years, rare-earth metals with triply oxidized state, lanthanide ions (Ln 3+ ), have been demonstrated as dopants, which can efficiently improve the optical and electronic properties of metal halide perovskite materials. On the one hand, doping Ln 3+ ions can convert near-infrared/ultraviolet light into visible light through the process of up-/down-conversion and then the absorption efficiency of solar spectrum by perovskite solar cells can be significantly increased, leading to high device power conversion efficiency. On the other hand, multi-color light emissions and white light emissions originated from perovskite nanocrystals can be realized via inserting Ln 3+ ions into the perovskite crystal lattice, which functioned as quantum cutting. In addition, doping or co-doping Ln 3+ ions in perovskite films or devices can effectively facilitate perovskite film growth, tailor the energy band alignment and passivate the defect states, resulting in improved charge carrier transport efficiency or reduced nonradiative recombination. Finally, Ln 3+ ions have also been used in the fields of photodetectors and luminescent solar concentrators. These indicate the huge potential of rare-earth metals in improving the perovskite optoelectronic device performances.

In this work, the electronic structure, and optical properties of As/Sb and Sb/Bi lateral heterostructures (LHS) along armchair and zigzag interfaces affected by strain were investigated by density functional theory. The LHSs presented strain-dependent band transformation characteristics and sensitivity features. And a reduction and transition of the bandgap was observed when the As/Sb and Sb/Bi LHS existed under compressive strain. The density of states and the conduction band minimum-valence band maximum characteristics exhibited corresponding changes under the strain. Then a spatial charge-separation phenomenon and strong optical absorption properties in the mid-infrared range can also be observed from calculated results. Theoretical research into As/Sb and Sb/Bi LHSs has laid a solid foundation for As/Sb and Sb/Bi LHS device manufacture., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

Rapid thermal annealing is an effective way to improve the optical properties of semiconductor materials and devices. In this paper, the emission characteristics of GaAs 0.92 Sb 0.08 /Al 0.3 Ga 0.7 As multiple quantum wells, which investigated by temperature-dependent photoluminescence, are adjusted through strain and interfacial diffusion via rapid thermal annealing. The light-hole (LH) exciton emission and the heavy-hole (HH) exciton emission are observed at room temperature. After annealing, the LH and HH emission peaks have blue shift. It can be ascribed to the variation of interfacial strain at low annealing temperature and the interfacial diffusion between barrier layer and well layer at high annealing temperature. This work is of great significance for emission adjustment of strained multiple quantum wells.

ZnO nanowires play a very important role in optoelectronic devices due to the wide bandgap and high exciton binding energy. However, for one-dimensional nanowire, due to the large surface to volume ratio, surface traps and surface adsorbed species acts as an alternate pathway for the de-excitation of carriers. Ar plasma treatment is a useful method to enhance the optical property of ZnO nanowires. It is necessary to study the optical properties of ZnO nanowires treated by plasma with different energies. Here, we used laser spectroscopy to investigate the plasma treatments with various energies on ZnO nanowires. Significantly improved emission has been observed for low and moderate Ar plasma treatments, which can be ascribed to the surface cleaning effects and increased neutral donor-bound excitons. It is worth mentioning that about 60-folds enhancements of the emission at room temperature can be achieved under 200 W Ar plasma treatment. When the plasma energy exceeds the threshold, high-ion beam energy will cause irreparable damage to the ZnO nanowires. Thanks to the enhanced optical performance, random lasing is observed under optical pumping at room temperature. And the stability has been improved dramatically. By using this simple method, the optical property and stability of ZnO nanowires can be effectively enhanced. These results will play an important role in the development of low dimensional ZnO-based optoelectronic devices.

The enhancement of optical properties via thermal annealing on InP/ZnS core/shell quantum dot (QD) film was investigated in this work. The increase of emission intensities of the QD films was observed after thermal annealing at 180 °C for 5 min. Through temperature dependence photoluminescence (TDPL) and power dependence photoluminescence (PL) measurement, the peak located at the low-energy shoulder was confirmed to be localized state emission and the high energy one comes from free-carrier emission. Moreover, from the TDPL spectra of the sample annealed at 180 °C for 5 min, the full width at half maximum (FWHM) of localization state emission was nearly the same before which is 250 K and then decreased with increasing temperature. However, the FWHM was decreased significantly when temperature increased in the untreated sample. We conclude that the escape of localization states with increasing temperature contributes to this anomaly phenomenon. Our studies have significance on the application of QDs in electroluminescence devices and down-conversion light-emitting devices.

Esophageal squamous cell carcinoma (ESCC) is widely regarded as one of the most lethal types of cancer around the world. The fact that early detection of ESCC could dramatically improve the treatment outcome of the patients has sparked considerable interest in searching for reliable and accurate diagnostic biomarkers. Recently, circular RNAs (circRNA) have emerged as a new type of non-coding RNAs with significant RNase resistance, wide abundance and remarkable internal diversity. There is also increasing evidence suggesting that circRNAs could be implicated in the pathogenesis of cancer and other diseases. In this study, we performed a comparative analysis of the global circRNA expression profiles in normal and malignant esophageal epithelial cell lines by a combination of RNA sequencing and bioinformatics analysis. We identified 813 significantly up-regulated and 445 down-regulated circRNA candidates, of which 32 were subsequently validated by quantitative real-time reverse transcription polymerase chain reaction analysis. The differentially expressed circRNAs were found to be associated with pathways involved in metabolism, cell apoptosis, proliferation and migration, which are commonly altered in cancer cells. Based on the obtained data, we constructed a circRNA-miRNA interaction network, in which circRNA9927-NBEAL1 represented the biggest node. Our study could lay the groundwork for further investigation concerning the pathological roles of circRNAs in ESCC., Competing Interests: None.

With special quasirandom structure approach and cluster expansion method combined with first-principle calculations, we explore the structure and electronic properties of monolayer Mo 1-x W x S 2 alloy with disordered phase and ordered phase. The phase transition from ordered phase to disordered phase is found to happen at 41 K and 43 K for x = 1/3 and x = 2/3, respectively. The band edge of VBM is just related with the composition x, while the band edge of CBM is sensitive to the degree of order, besides the concentration of W. Near the CBM band edge, there are two bands with the Mo-character and W-character, respectively. It is found that in disordered phase the Mo-character band is mixed with the W-character band, while the opposite happens in ordered phase. This result leads to that the splitting of two bands near CBM in ordered phase is larger than in disordered phase and gives rise to the smaller band gap in ordered phase compared to the disordered phase. The electron effective mass in ordered phase is smaller than in disordered phase, while the heavy hole effective mass in ordered phase is larger than that in disordered phase.