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Purpose: The purpose of this study is to investigate the influence of varying concentrations of nano-SiO2 particle doping on the structure and properties of the micro-arc oxidation (MAO) coating of 7075 aluminum alloy. This research aims to provide novel insights and methodologies for the surface treatment and protection of 7075 aluminum alloy. Design/methodology/approach: The surface morphology of the MAO coating was characterized using scanning electron microscope. Energy spectrometer was used to characterize the elemental content and distribution on the surface and cross section of the MAO coating. The phase composition of the MAO coating was characterized using X-ray diffractometer. The corrosion resistance of the MAO coating was characterized using an electrochemical workstation. Findings: The results showed that when the addition of nano-SiO2 particles is 3 g/L, the corrosion resistance is optimal. Originality/value: This study investigated the influence of different concentrations of nano-SiO2 particles on the structure and properties of the MAO coating of 7075 aluminum alloy. [ABSTRACT FROM AUTHOR]

This study uses 7075 aluminum alloy as the base material and employs micro arc oxidation technology to prepare ceramic coatings with different concentrations of graphene particles on the surface of the 7075 aluminum alloy. The effects of graphene particle concentration on micro arc oxidation behavior and coating performance were investigated through X‐ray diffraction, scanning electron microscope, electrochemical testing, and other performance characterization methods. The research results show that the addition of graphene particles helps to promote the transformation of metastable γ‐Al2O3 to stable α‐Al2O3, thereby enhancing the corrosion properties of the coating. When the concentration of graphene particles is 3 g/L, the prepared micro arc oxidation coating has the maximum thickness and hardness, which are 17.13 µm and 886.76 HV0.3, respectively, while the porosity and roughness are the smallest, which are .39 µm and 4.79%, respectively. Electrochemical test results show that the self‐corrosion current density is the smallest at this concentration, which is 2.323 × 10−9A/cm2. Therefore, the addition of graphene particles can effectively improve the corrosion properties of 7075 aluminum alloy. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to examine the impact of MoS2 on the microstructure and characteristics of micro-arc oxidized (MAO) ceramic coatings created on ZK60 magnesium alloy through the addition of varying concentrations of MoS2 particles to the electrolyte, aiming to enhance the corrosion resistance of magnesium alloy. Design/methodology/approach: The surface morphology, roughness and phase composition of the coatings were analyzed using scanning electron microscopy, a hand-held roughness tester and an X-ray diffractometer, respectively, and the corrosion resistance of the MAO coatings prepared by the addition of different contents of MoS2 particles was tested and analyzed using an electrochemical workstation. Findings: The results demonstrate that MoS2/MgO composite coatings have been successfully prepared on the surface of magnesium alloys through micro-arc oxidation. Furthermore, the corrosion resistance of the ZK60 magnesium alloy prepared with the addition of 1.0 g/L MoS2 was the best compared to the other samples. Originality/value: MoS2 particles were able to penetrate the coatings successfully during the micro-arc oxidation process, acting as a barrier in the micropores to prevent the corrosion medium from touching the surface, thus improving the corrosion resistance of the sample. The electrochemical workstation was used to study the corrosion resistance of the MoS2/MAO coating on the ZK60 magnesium alloy. [ABSTRACT FROM AUTHOR]

In order to enhance the corrosion and wear resistance of aluminum alloys in complex and variable environments, an Al2O3 ceramic film was prepared on the surface of 7A04 aluminum alloy in a silicate electrolyte system using a micro‐arc oxidation technique. Subsequently, antimony tin oxide (ATO) nanoparticles were used to dope the micro‐arc oxidation film to enhance the protective properties of the 7A04 aluminum alloy. The structural characteristics of the film were investigated by examining the surface and cross‐sectional morphology and the composition of the physical phases. The results show that ATO nanoparticles can promote the micro‐arc oxidation reaction, improve the surface morphology of the film layer, increase the thickness of the film layer and the denseness after sintering, and enter the film layer in the form of melt wrapping, which plays a role in refining the grain. In the study of the wear resistance and corrosion resistance of ATO‐doped ceramic film layers, it was found that the introduction of ATO nanoparticles did not significantly improve the wear resistance of the micro‐arc oxide ceramic film layers but significantly improved the corrosion resistance of the film layers. [ABSTRACT FROM AUTHOR]

Objective To investigate the differential expression levels of Pim1 and Notch1 in breast tissues and their clinical and prognostic significance. Methods qRT-PCR, immunohistochemistry and databases were used to detect the mRNA and protein levels of Pim1 and Notch1 genes in adjacent normal breast tissues (ANBT), usual ductal hyperplasia (UDH), ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC). The relation between Pim1/Notch1 expression and the clinicopathological parameters of breast cancer patients was analyzed. The prognostic value of Pim1 and Notch1 protein in breast cancer was evaluated by Kaplan-Meier Plotter databases. Results The expression of Pim1 mRNA in breast cancer tissues was increased. The expression of Pim1 protein in the breast cancer tissues was significantly decreased. The expression of Pim1 mRNA was markedly associated with lymph node metastasis and advanced TNM stage. The expression of Pim1 protein was significantly decreased in the patients with lymph node metastasis or histological grade 3. The patients with low expression of Pim1 had a shorter relapse-free survival (P=0.000). The expression of Notch1 mRNA and protein in breast cancer were higher than those in normal breast tissues. Notch1 mRNA was closely related to the lymph node metastasis, high grade and advanced stage. Notch1 protein expression in lymph node metastasis group had markedly increased. The overall survival time of patients with high level of Notch1 was shorter (P=0.025). The protein levels of Pim1 and Notch1 were negatively correlated in breast cancer tissues (r=-0.385, P=0.001). Conclusion Low Pim1 expression and high Notch1 expression may promote the carcinogenesis and progression of breast cancer and may be risk factors for poor prognosis. Pim1 and Notch1 may be used as potential biomarkers for clinical evaluation of breast cancer patients.

The genetic mechanisms of osmoregulation accompanied by salinity changes in aquatic crustaceans are still unclear. In this study, two different salinity transition experiments were conducted, and the gene expression profiles of gill tissues between the two salinity transition processes were compared to unveil the genetic basis of osmoregulation and high/low salinity acclimation for Eriocheir sinensis. A total of 910 genes were significantly differentially expressed within the two salinity transition processes. Genes associated with ion transport, signal transduction, immune response, and DNA repair generally showed fluctuated expressions in the two salinity transition processes. Genes associated with the nitrogen compound metabolic process, sexual reproduction system, and ammonium transport, such as AASS, HDAC4, VG, MARF1, VMO1, and RHBG, were upregulated in a high salinity environment. Genes associated with lipid metabolism processes, such as OXCT1, TEX2, DIB, and CHKB, were upregulated in a low salinity environment. Results revealed the common and specific responsive mechanism of osmoregulation and different levels of salinity acclimation within the two salinity transition processes of E. sinensis. This study provides valuable genetic resources and novel insights into the osmoregulation research of crustaceans. KEY WORDS: crustacean, RNA-seq, osmoregulation, salinity acclimation, Eriocheir sinensis, INTRODUCTION Salinity changes are challenges that aquatic species need to adapt to, which is a biological process that several specific species must fulfill to accomplish their reproduction, growth, and development [...]