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The A/H1N1pdm09 influenza virus, which caused the 2009 pandemic, has since become a recurring strain in seasonal influenza outbreaks. Given the ongoing threat of influenza, protein subunit vaccines have garnered significant attention for their safety and effectiveness. This review seeks to highlight the latest developments in protein subunit vaccines that specifically target the A/H1N1pdm09 virus. It will also examine the structure and replication cycle of influenza A viruses and compare different types of influenza vaccines. Additionally, the review will address key aspects of H1N1 protein subunit vaccine development, such as antigen selection, protein expression systems, and the use of adjuvants. The role of animal models in evaluating these vaccines will also be discussed. Despite challenges like antigenic variability and the complexities of vaccine production and distribution, protein subunit vaccines remain a promising option for future influenza prevention efforts. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) is an important signaling molecule involved in regulating plant processes to cope with abiotic stress. S-allyl-L-cysteine (SAC) is known to induce NO synthesis in animals. However, it is unknown whether SAC can trigger NO biosynthesis, regulate Cd transport, or alleviate Cd stress in plants. After being sprayed with 0.2 mM SAC, rice seedlings had a NO content that was 1.8 times higher than that of the control (ctrl) group at the ninth hour, which then gradually decreased. The expressions of Cd uptake and transport genes in the roots (including OsNRAMP5, OsNRAMP1, and OsHMA2) were markedly downregulated by 27.2%, 24.8%, and 49.1%, respectively, 72 h after SAC spraying treatment. The Cd content in seedling roots' cell wall (CW) components significantly increased by 43.5% compared to that of the ctrl group. The Cd content in the shoots and roots decreased by 49.0% and 29.8%, respectively. Cd stress in the seedlings was also substantially alleviated. In conclusion, spraying rice seedlings with SAC triggered an increase in NO synthesis, regulated the expression of genes related to Cd transport, increased Cd fixation in the root CW components, and reduced Cd accumulation in the roots and shoots. [ABSTRACT FROM AUTHOR]

In this study, the microwave dielectric properties of Co2+‐substituted BaZnP2O7 ceramics prepared through conventional solid‐state synthesis were investigated. X‐ray diffraction, Rietveld refinement, energy‐dispersive spectroscopy, and Raman spectroscopy all indicated that BaZn1−xCoxP2O7 ceramics sintered at 875°C were composed of a single phase. The lattice strain and crystallite size were estimated using Williamson–Hall (W–H) method. Both the scanning electron microscopy images and density measurements showed that Co2+ ions had an effect on the grain growth and densification of ceramics. The microwave dielectric properties were influenced by the intrinsic and extrinsic factors that varied with the increase of x value. An optimal performance (εr = 7.62, Q × f = 600 45 GHz, and τf = −74 ppm/°C) was achieved at x =.01. The porosity and relative density played a significant role in the dielectric constant εr: the denser the ceramic structure, the larger the dielectric constant. The Q × f and τf values were negatively correlated with the full width at half maximum of the Raman vibrational peak at approximately 1049 cm−1. Moreover, the Q × f value was improved compared to that of the undoped BaZnP2O7 ceramics. Therefore, cobalt ion substitution is an effective strategy to enhance the performance of microwave dielectric ceramics. [ABSTRACT FROM AUTHOR]

Low‐temperature‐sintered Ni0.5Cu0.125Zn0.375Fe1.98O4 ferrites co‐added with x wt% (x = 0.00‐0.25 wt%) La2O3 and 0.25 wt% Bi2O3 were successfully prepared via conventional solid‐phase reaction method. The phase composition, microstructure, magnetic properties, and especially power loss variation of the samples were systematically studied. The results showed that all samples possessed a single spinel phase structure at a sintering temperature of 900°C, exhibiting high degree of densification and uniform grains. The appropriate amount of La2O3 additive improved the saturation flux density and permeability of NiCuZn ferrites, simultaneously reducing the coercivity and power loss. The maximum permeability and the lowest power loss were achieved at x = 0.15 wt%. The corresponding sample had the homogeneous microstructure and excellent magnetic properties, being a promising low‐temperature co‐fired ferrite candidate for magnetic power components. [ABSTRACT FROM AUTHOR]

A series of Ba1.5Sr1.5Co2+xZrxFe24‐2xO41 hexaferrites (x = 0.00, 0.01, 0.03, 0.05, 0.07, and 0.09) were successfully prepared by the conventional solid‐state reaction method. It was found that as the Co2+ and Zr4+ ions entered the hexaferrite structure, the lattice parameters increased, whereas the relative density increased when x = 0.00‐0.03 and then decreased. A suitable amount of substitution increased the DC resistivity, reduced the magnetic and dielectric losses, and made the μ′$\mu ^{\prime}$ and ε′$\varepsilon ^{\prime}$ closer to each other. At x = 0.03, the relative density and DC resistivity of the samples reached their maxim. Besides, both the magnetic and dielectric losses were lowest within the frequency range of 10 MHz‐1 GHz. Meanwhile, the hexaferrite was impedance matched to free space, and the miniaturization factor was about 15. Therefore, this low‐loss ferrite with almost equal permeability and permittivity could be meaningful for antenna miniaturization and high‐frequency applications. [ABSTRACT FROM AUTHOR]