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Estrogen is an essential sex steroid that functions in numerous biological systems including female reproduction, neuroendocrine, vascular, skeletal, and immune systems. The synthesis of estrogen is controlled by the rate-limiting enzyme, which has been confirmed to exist in two different forms, named brain aromatase and ovary aromatase, and encoded by cyp19a1a and cyp19a1b respectively in teleosts. However, existing studies have primarily focused on the expression and function of cyp19a1b in the brain and cyp19a1a in the gonad, the roles of cyp19a1b in the female gonad of teleosts are largely unknown. In our previous study, we cloned the full length of the cyp19a1b gene from a natural triploid teleost Qi River crucian carp (Carassius auratus), andthe spatial and temporal expression patterns of cyp19a1b mRNA were detected. To further clarify the roles of cyp19a1b in the ovarian differentiation of Qi River crucian carp, we produced a polyclonal antibody of Cyp19a1b in this study. Western blotting results showed that Cyp19a1b was mainly expressed in the brain and then in the ovary, heart, liver, and muscle. During embryogenesis, Cyp19a1b was abundantly expressed in the neurula stage. Immunohistochemistry demonstrated that Cyp19a1b was expressed in the radioactive glial cells (RGCs) of the brain from 20 days after hatching (dah) and the somatic cells of the ovaries from 30 dah, the critical period of ovarian differentiation in Qi River crucian carp. With the treatment of letrozole, an inhibitor of the aromatase, the expression of Cyp19a1b was downregulated both in the brain and gonad. Our results suggested that Cyp19a1b might be involved in the development of the nervous system and also participate in the ovarian differentiation of Qi River crucian carp. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) have emerged as a promising alternative to lithium-ion batteries (LIBs) due to the abundant availability of sodium, lower costs, and comparable electrochemical performance characteristics. A thorough understanding of their performance features is essential for the widespread adoption and application of SIBs. Therefore, in this study, we investigate the output characteristics and electrochemical impedance spectroscopy (EIS) features of sodium-ion batteries (SIBs) under various states. The research results show that, unlike conventional lithium iron phosphate (LFP) batteries, SIBs exhibit a strong linear relationship between state of charge (SOC) and open-circuit voltage (OCV) across various SOC and temperature conditions. Additionally, the discharge capacity of the battery remains relatively stable within a temperature range of 15 °C to 35 °C; when the temperatures are outside this range, the available capacity of the sodium-ion battery reduces significantly. Moreover, the EIS profiles in the high-frequency region are predominantly influenced by the ohmic internal resistance, which remains largely unaffected by SOC variations. In contrast, the low-frequency region demonstrates a significant correlation between SOC and impedance, with higher SOC values resulting in reduced impedance, indicated by smaller semicircle radii in the EIS curves. This finds highlights that EIS profiling can effectively monitor SOC and state of health (SOH) in SIBs, offering a clear correlation between impedance parameters and the battery's operational state. The research not only advances our understanding of the electrochemical properties of SIBs but also provides a valuable reference for the design and application of sodium-ion battery systems in various scenarios. [ABSTRACT FROM AUTHOR]

Based on the traditional re-entrant honeycomb, a novel re-entrant octagon honeycomb (ROH) is proposed. The deformation mode of the honeycomb under quasi-static compression is analyzed by numerical simulation, and the results are in good agreement with the experimental ones. The deformation modes, mechanical properties, and energy absorption characteristics of ROH along the impact and perpendicular directions gradient design are investigated under different velocities. The results indicated that the deformation mode of ROH is affected by gradient design along the direction of impact and impact speed. In addition, gradient design along the direction of impact can increase the initial peak stress of ROH and accelerate its densification phase. Gradient design perpendicular to the impact direction can enhance the energy absorption performance of ROH, especially for ROH, with wall thickness increasing from the inside outwards. Compared to ROH with uniform wall thickness at the same relative density, ROH with a gradient design can increase the plateau stress by over half. With the elevation of impact velocity, the plateau stress and specific energy absorption exhibit an upward trend, aligning with the dynamic performance pattern observed in conventional honeycombs. The results can be used as a reference for the design and application of honeycomb and provide a new idea for developing more efficient and reliable energy-absorbing materials. [ABSTRACT FROM AUTHOR]