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Sleep deprivation (SD) impairs learning and memory. Investigating the role of epigenetic modifications, such as 5-methylcytosine (m5C), in SD is crucial. This study established an SD mouse model and assessed the mRNA levels of m5C-related genes in brain tissue to identify potential candidates. Results indicated a significant elevation of NSUN2 in the SD group. Behavioral assessments using the Morris water maze test revealed cognitive impairments. Notably, inhibiting NSUN2 markedly alleviated these cognitive deficits and reduced autophagy in SD mice. Mechanistically, NSUN2 inhibition led to a pronounced decrease in PTEN levels, and the m5C modification of PTEN, which was increased by SD, was significantly reduced following NSUN2 knockdown. It was found that NSUN2 stabilizes PTEN mRNA through methylation. In the SD group, PTEN protein levels were elevated, and this increase was counteracted by NSUN2 inhibition. Collectively, the upregulation of PTEN may diminish the beneficial effects of NSUN2 inhibition on cognitive function and autophagy in SD mice. This study suggests that targeting NSUN2 and PTEN could be a novel therapeutic approach to ameliorate cognitive impairments and autophagy associated with SD, offering a promising strategy for the clinical management of SD-related cognitive deficits. [ABSTRACT FROM AUTHOR]

In present study, the texture evolution during cold rolling and subsequent annealing of a Fe-24Cr-22Ni-7Mo super austenitic stainless steel was investigated, and new insights into the mechanisms of texture evolution were obtained. The results show that macrotexture evolution during cold rolling can be categorized into two stages. Below 33.3% cold reduction, the material form strong Goss, Copper, and S texture component due to dislocation plane slipping. Above 33.3% reduction, strong Brass, Goss, and Copper-Twin texture components are formed, accompanied by a decrease in Copper and S component content. Moreover, when the cold reduction reaches 66.6%, the strength of the γ-fibre texture suddenly increases. This increase is attributed to the rotation of the Copper-oriented grains and the Copper-Twin-oriented grains in the lamellar twin region to {111} and {111} along < 011>//TD direction, respectively. It is significant to note that twinning plays a dominant role in the formation of the Brass-type texture in the super austenitic stainless steel at large deformation. Additionally, the annealing of cold deformed materials results in the formation of random and scattered recrystallization texture. This may be due to the small difference in deformation energy storage of grains with different orientations after austenite deformation. [ABSTRACT FROM AUTHOR]

Understanding the relationship between dislocation structure evolution and strain hardening behavior is crucial for the development of high-strength and high-ductility alloys. In this work, the strain hardening mechanism of S32654 super-austenitic stainless steel is studied by electron backscatter diffraction and transmission electron microscopy. S32654 is characterized by a constant high strain hardening rate accompanied by 835 ± 10 MPa ultimate tensile strength and 67 ± 3% elongation. Deformation microstructures at different strain levels are investigated in order to unveil the influence of microstructure on mechanical properties. Research results indicate that although the strain hardening curve of S32654 shows similarities to high-strength twinning-induced plasticity (TWIP) steels, deformation-induced twinning is not the primary strain hardening mechanism for S32654. With increasing deformation, the evolution of dislocation structures in S32654 is mainly dominated by the continuous refinement of slip bands. The spacing between slip bands, as a microstructural parameter, can describe the flow stress curve. The TWIP effect only contributes to the strain hardening of S32654 in the later stages of deformation. [ABSTRACT FROM AUTHOR]

Hypoxic-ischemic brain damage (HIBD) is a familiar neurological disorder. Emerging reports manifest that microRNAs (miRs) are related to the progression of HIBD. The goal of this study is to explore the mechanism of miR-192-5p in HIBD via regulation of Yes-associated protein 1 (YAP1)-mediated Hippo signaling pathway. The miR-192-5p, YAP1, and Hippo pathway-related factors Phospho (p)-Triaminoguanidinium azide (TAZ) in hippocampal tissues and neurons were detected. The regulatory relationship between miR-192-5p and YAP1 was verified. Neonatal hypoxic ischemia and oxygen–glucose deprivation (OGD) were used to simulate HIBD in vivo and in vitro. The neurobehavioral impairment, neuronal damage and vascular endothelial growth factor (VEGF) expression of neonatal rats in each group were detected. The viability, apoptosis and VEGF expression of hippocampal neurons in each group were also examined. MiR-192-5p expression was elevated while YAP1 expression was reduced in hippocampal tissues of HIBD rats in vivo and OGD neurons in vitro. MiR-192-5p had a targeting relation with YAP1. Suppressed miR-192-5p or overexpressed YAP1 in HIBD rats alleviated neurobehavioral impairment and neuronal damage, and decreased the expression levels of p-TAZ and VEGF expression in vivo. Reduced miR-192-5p or augmented YAP1 decelerated the neuron apoptosis, decreased the p-TAZ level and VEGF level and promoted cell viability of OGD hippocampal neurons in vitro. The study highlights that inhibited miR-192-5p protects against HIBD via regulation of YAP1 and Hippo signaling pathway, which is beneficial for HIBD treatment. [ABSTRACT FROM AUTHOR]

A new water-soluble calcia-based ceramic core of using epoxy resin binder was developed for investment casting by aqueous gel casting. The influences of dispersant addition and solid loading on the rheological property of the slurries were investigated. The low-shrinkage and high-strength ceramic body was obtained by adjusting binder addition and solid loading. The water-soluble behavior of the calcia-based ceramic core and its solution mechanism were studied. The results show that the 48 vol% slurry composing of 6 wt% dispersant content, 16 wt% binder content, and 20 wt% hardener content can prepare a stable and fluidic slurry, and the bending strength of the dried green body is 29.5 ± 1.4 MPa, the linear shrinkage is 3.62 %, and the green relative density is 58.5 % with a homogeneous microstructure. After sintering at 1300 °C, the ceramic core exhibits a uniform microstructure with a bending strength of 25 ± 1.2 MPa, a sintered shrinkage of 11.31 %, a relative density of 92.3 %, and an apparent porosity of 30.5 %. The solubility rate of the ceramic core is 2.83 kg/min m, and the dissolution of the ceramic core in water is exothermal. The water-soluble calcia-based ceramic core fabricated by aqueous gel casting using epoxy resin could overcome the poor leachability of the common ceramic core and enhanced the production efficiency. [ABSTRACT FROM AUTHOR]

Zn has been added to the Al-12.5wt%Si-2wt%Cu-1wt%Mg (abbrev Al-12.5Si-2Cu-Mg) alloy. By utilizing optical microscope (OM), X-ray diffraction (XRD), and scanning electron microscope (SEM), the microstructure and phase structure of the alloy were investigated. The alloy's mechanical properties and wear resistance were evaluated. The results demonstrate that the as-cast microstructure of Al-12.5Si-xZn-2Cu-1Mg alloy consists of (α-Al + Si) eutectic, a minor amount of primary Si, θ-Al2Cu phase, Q-Al5Cu2Mg8Si6 phase, and π-Al8Mg3FeSi6 phase. In the final solidification zone of an alloy with a Zn content greater than 2%, a Zn-rich granular phase is observed. With an increase in Zn content, the size of the Si phase decreases and the number of θ-Al2Cu phase decreases. Zn slightly raises the formation temperature of primary Si, decreases the (α-Al + Si) eutectic transition temperature, and significantly decreases the formation temperatures of θ-Al2Cu and Q-Al5Cu2Mg8Si6 phases. The yield strength and hardness of the as-cast alloy raise with increasing Zn content, whereas the elongation decreases and the tensile strength first increases and then decreases slightly. The tensile strength is the greatest when the weight percentage of Zn is 2wt%. After T6 treatment, the tensile strength, yield strength, and hardness of the alloy rise in proportion to the alloy's Zn content, and its resistance to wear is greatly enhanced. [ABSTRACT FROM AUTHOR]