Search

Marek's disease (MD), an immunosuppressive disease induced by the Marek's disease virus (MDV), is regarded as an ideal model for lymphoma research to elucidate oncogenic and anti-oncogene genes. Using this model, we found that circRUNX2.2, derived from exon 6 of RUNX2, was significantly upregulated in MDV-infected tumorous spleens. In this study, we deeply analyzed the potential role of circRUNX2.2 in lymphoma cells. An open reading frame (ORF) in circRUNX2.2 with no stop codon was predicted, and small peptides (named circRUNX2.2-rt) presenting multiple ladder-like bands with different molecular weights encoded by circRUNX2.2 were detected via Western blotting assay. The polysome fraction assay reconfirmed the translation ability of circRUNX2.2, which could be detected in polysome fractions. Subsequent analysis verified that it translated in a rolling circle manner, rather than being assisted by the internal ribosome entry site (IRES) or m6A-mediated mechanism. Furthermore, we found that circRUNX2.2-rt was potently induced in MSB1 cells treated with sodium butyrate (NaB), which reactivated MDV and forced the MDV transition from the latent to reactivation phase. During this phase, MDV particles were clearly observed by electron microscopy, and the viral gene pp38 was also significantly upregulated. A biological function study showed that circRUNX2.2-rt promoted cell proliferation and cell cycle transition from the S to G2 phase and inhibited the apoptosis of MSB1. Further immunoprecipitation and mass spectrometry assays showed that 168 proteins potentially interacting with circRUNX2.2-rt were involved in multiple pathways related to cell cycle regulation, which proved that circRUNX2.2-rt could bind or recruit proteins to mediate the cell cycle. [ABSTRACT FROM AUTHOR]

The chicken infectious anemia virus (CIAV) has been reported in major poultry-producing countries and poses a significant threat to the poultry industry worldwide. In this study, two Marek's disease virus (MDV) recombinants, rMDV-CIAV-1 and rMDV-CIAV-2, were generated by inserting the CIAV VP1 and VP2 genes into the MDV vaccine strain 814 at the US2 site using the fosmid-based rescue system. For rMDV-CIAV-1, an internal ribosome entry site was inserted between VP1 and VP2, so that both proteins were produced from a single open reading frame. In rMDV-CIAV-2, VP1 and VP2 were cloned into different open reading frames and inserted into the MDV genome. The recombinant viruses simultaneously expressed VP1 and VP2 in infected chicken embryo fibroblasts and exhibited growth kinetics similar to those of the parent MDV. The two recombinant viruses induced antibodies against CIAV in chickens. A single dose of the recombinant viruses provided strong protection against CIAV-induced anemia in chickens. These recombinant VP1- and VP2-expressing MDVs are potential vaccines against CIAV in chickens. [ABSTRACT FROM AUTHOR]

The subgroup J avian leukosis virus (ALV-J), a retrovirus, uses its gp85 protein to bind to the receptor, the chicken sodium hydrogen exchanger isoform 1 (chNHE1), facilitating viral invasion. ALV-J is the main epidemic subgroup and shows noteworthy mutations within the receptor-binding domain (RBD) region of gp85, especially in ALV-J layer strains in China. However, the implications of these mutations on viral replication and transmission remain elusive. In this study, the ALV-J layer strain JL08CH3-1 exhibited a more robust replication ability than the prototype strain HPRS103, which is related to variations in the gp85 protein. Notably, the gp85 of JL08CH3-1 demonstrated a heightened binding capacity to chNHE1 compared to HPRS103-gp85 binding. Furthermore, we showed that the specific N123I mutation within gp85 contributed to the enhanced binding capacity of the gp85 protein to chNHE1. Structural analysis indicated that the N123I mutation primarily enhanced the stability of gp85, expanded the interaction interface, and increased the number of hydrogen bonds at the interaction interface to increase the binding capacity between gp85 and chNHE1. We found that the N123I mutation not only improved the viral replication ability of ALV-J but also promoted viral shedding in vivo. These comprehensive data underscore the notion that the N123I mutation increases receptor binding and intensifies viral replication. Author summary: Attachment is a critical initial step in retroviral infections. The RBD of gp85 in ALV-J is critical for binding to the cell membrane receptor, chNHE1. This investigation establishes a strong link between the heightened replication ability of the layer strain JL08CH3-1 and the enhanced binding capacity exhibited by gp85 toward chNHE1 compared to the prototype strain HPRS103. We found for the first time that the N123I mutation within the RBD region of gp85 increased the binding capacity between gp85 and chNHE1 and enhanced the replication ability of ALV-J. Our results provide important information on the implications of mutations within the RBD region of gp85 and highlight the importance of monitoring variations in the RBD region of ALV-J to prevent future outbreaks. [ABSTRACT FROM AUTHOR]

Due to the exist of the inevitable dimensional tolerance and assembling errors in the ball bearing, the interference amounts between the inner ring and the connected shaft are uncertain but bounded, which could directly affect the dynamics performance of the rotor-ball bearing system. Whereas, most of the works on the field of dynamics in a ball bearing have considered the varying compliance (VC) vibration as deterministic vibration and there are few quantitative studies considering the uncertain factors. Therefore, in this paper, an uncertain ball bearing-rotor dynamic model is presented based on the Chebyshev interval method. Firstly, the uncertain interference amounts between the bearing inner ring and the connected shaft are modeled by the Chebyshev interval method. Then the radial clearance and actual interference amounts of ball bearing are derived by the bearing-shaft interference fit model. The time-dependent ball-raceway contact probability is formulated and the influence of the average and deviation coefficient of the initial interference amounts on the vibration behaviors of the rotor under various rotational speeds are investigated based on the double degrees of freedom (2-DOF) ball bearing system. The numerical cases show that the amounts of the bearing-shaft interference fit are uncertain and could be affected by rotational speed, which have an obvious influence on the dynamic performance of the rotor-ball bearing system. Reasonable design of the interference amounts could reduce the dispersion of the displacement and time-varying stiffness. The numerical results obtained by the present study are compared to the Monte Carlo simulation (MCS), which show the validity of the study. [ABSTRACT FROM AUTHOR]

The counterrotating compressor of Rotor-Rotor-Stator (R/R/S) layout is considered to be a crucial technical path for engine thrust-to-weight improvement because it can achieve a high-pressure rise level with low weight and a short axial length. To guide the selection of key aerodynamic parameters in counterrotating compressor design schemes, a zero-dimensional physics–based model is proposed, which can calculate kinetic energy variation across the compressor rotor passages based on enthalpy rise and velocity triangles. Numerical investigations on two counterrotating compressors with different pressure ratios have been conducted employing the Reynolds-averaged Navier-Stokes (RANS) method to validate and support the physics-based model. It was found that the model prediction results and CFD numerical results of two counterrotating compressors showed a global agreement, with the deviations in relative kinetic energy variation coefficient less than 3%, implying the accuracy of the proposed model. This model can be used for the loop iteration between the one-dimensional (1D) and two-dimensional (2D) preliminary design schemes of a counterrotating compressor. [ABSTRACT FROM AUTHOR]

Pico‐projection displays are the main developing direction for future projection displays, but the balance between the optical efficiency and the system size is still a big concern. This paper presents a pico‐projector design based on micro‐LED (μLED) light sources. Firstly, based on the analysis of the characteristics of μLED, a highly integrated microlens array is designed to improve the system efficiency by reshaping the spatial light distribution. In addition, the matching relationship between the aperture angle of projection lens and the divergence angle of μLED is studied, and on this basis, a set of four‐piece spherical lens group is proposed to achieve compact size. Simulation results show that the μLED equipped with the microlens array can concentrate about 86% of the light energy within a dispersion angle of ±20°, thus increasing the light energy utilization by about 3.5 times and reducing the size of the pico‐projector to 30.18 mm3. The designed pico‐projector has high performance and compact size with great potential for future applications. [ABSTRACT FROM AUTHOR]

Hepatitis B virus (HBV) only infects humans and chimpanzees, posing major challenges for modeling HBV infection and chronic viral hepatitis. The major barrier in establishing HBV infection in non-human primates lies at incompatibilities between HBV and simian orthologues of the HBV receptor, sodium taurocholate co-transporting polypeptide (NTCP). Through mutagenesis analysis and screening among NTCP orthologues from Old World monkeys, New World monkeys and prosimians, we determined key residues responsible for viral binding and internalization, respectively and identified marmosets as a suitable candidate for HBV infection. Primary marmoset hepatocytes and induced pluripotent stem cell-derived hepatocyte-like cells support HBV and more efficient woolly monkey HBV (WMHBV) infection. Adapted chimeric HBV genome harboring residues 1–48 of WMHBV preS1 generated here led to a more efficient infection than wild-type HBV in primary and stem cell derived marmoset hepatocytes. Collectively, our data demonstrate that minimal targeted simianization of HBV can break the species barrier in small NHPs, paving the path for an HBV primate model. Hepatitis B virus is an almost uniquely human-tropic pathogen for which model systems are scarce. Here, the authors determine key residues within the HBV receptor that form a barrier in the HBV life cycle in primates and identify marmosets as a model candidate for infection with simian-tropic HBV. [ABSTRACT FROM AUTHOR]

Micro‐LED is one of the most promising display devices, which has Micron‐sized inorganic structure. The miniaturized size of Micro‐LED leads to a large amount of sidewall emission, which causes crosstalk for display devices. To solve the problem, this paper proposes a novel Micro‐LED structure by designing a sidewall light guide structure where SiO2 and TiO2 layers are successively added to the Micro‐LED's sidewall to form a total reflection layer. Thereby, large part of the light emitting from sidewall can be guided to the front of this structure. The simulation results show that RGB Micro‐LEDs with the sidewall light guide structure can improve the efficiency of front emission in the range of sidewall inclination degree from 0° to 50°. Further, the ratio of front emission to the total emission can be improved to 68%. [ABSTRACT FROM AUTHOR]

For some flight missions, such as autonomous landing on mobile platforms, the demands on indicators such as target-tracking accuracy and so on are relatively high. To achieve this, a guidance system with excellent precision is necessary. An asymmetric tracking differentiator based on a tracking differentiator is proposed to establish the guidance system. On the basis of the proposed asymmetric tracking differentiator, an altitudinal and horizontal helicopter guidance system structure is designed. In this paper, a guidance law is designed in order to meet the accuracy and precision requirements in the autonomous landing and transition process. Apart from that, a plane-motion-guidance law is also designed to realize static and dynamic point tracking, linear route tracking and circular route tracking to improve the trajectory smoothness and accuracy. Finally, simulations of the autonomous landing process on moving platforms, including three stages, namely approaching, tracking and landing, are completed. The application effects and precision of the autonomous landing guidance algorithm under different wave heights and period conditions are analyzed through the obtained simulation curves. [ABSTRACT FROM AUTHOR]

A localized surface plasmon (LSP) coupling nanorod $\mu $ LED using graphene as a transparent conductive electrode structure was demonstrated. The optical performance of the $\mu $ LED with LSP coupling is enhanced by about 36% in external quantum efficiency and 84% in photoluminescence measurements as compared with the LSP-free sample. This LSP coupling enhancement relies on the very large sidewall area provided by the nanorod structure and the zero distance contact between the nanoparticles and nanorods. This work provides a broad prospect for the application of LSP in the $\mu $ LED field. [ABSTRACT FROM AUTHOR]

• Evaluation of making up ChatGPT4o in the preliminary pathological diagnosis of bone tumors. • ChatGPT-4o's proficiency in analyzing pathological images and providing initial diagnoses of bone tumor characteristics is comparable to that of senior pathologists in the Tertiary hospital doctors group, with both surpassing the Remote grassroots doctors group. • AI, like ChatGPT-4o, has the potential to enhance diagnostic capabilities for remote grassroots doctors and improve sensitivity to reduce missed diagnosis rates among tertiary hospital doctors in identifying bone tumors. [ABSTRACT FROM AUTHOR]

Al-Si-Mg-Cu-Ni alloy is widely used in the manufacture of high-performance car engine parts. Coarse, dendritic α-Al and large primary Si are common in Al-Si-Mg-Cu-Ni alloy DC casting billet, which is harmful to the performance of the final product. In this paper, a pulsed magnetic field melt treatment technique was applied to the melt in the launder of a DC casting platform to modify the α-Al and primary Si in the billet. A transient numerical model was established to analyze the electromagnetic field, flow field and temperature field in the melt during the pulsed magnetic field treatment. The effect of the magnetic energy on the clusters in the melt was analyzed. We found that during the pulsed magnetic field melt treatment, the number of clusters close to the critical size was increased due to the cluster formation work being reduced by the magnetic energy, which facilitated nucleation and refined the solidification structure. Furthermore, the flow velocity increased, and temperature homogenized in the melt during the pulsed magnetic field melt treatment, which benefitted the clusters close to the critical size distributed and maintained in the melt uniformly. The experimental results show that the α-Al and primary Si were small and homogeneous following the pulsed magnetic field melt treatment. The size of α-Al and primary Si was reduced by 25.6–44.4% and 32.2–54.1%, respectively, in the billet center compared to the conventional process. [ABSTRACT FROM AUTHOR]