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The mechanism of steel corrosion in recycled brick powder (RBP)–incorporated concrete remains unclear considering the potential utilization of active RBP for low-carbon design in engineering structures. This study aimed to point the influence of RBP on the corrosion behavior of reinforced concrete under the action of chloride or carbonation. Mortar containing RBP (RBPM) was used in this study to concentrate on the effect of RBP and limit the effect of coarse aggregate. The mechanical, chloride penetration, and carbonation properties of RBPM were first investigated. Then the steel corrosion in reinforced RBPM under the action of chloride or carbonation was evaluated by different electrochemical tests. The underlying mechanisms were elucidated by the chemical composition, pH value, and pore structures of RBPM. The results showed that the compressive strength of mortar decreased 21.7% when 30% RBP was used. The addition of RBP reduced the chloride ion permeability but increased the carbonation depth of RBPM. The corrosion caused by chloride penetration in reinforced RBPM was reduced with a higher corrosion potential and lower corrosion current density, which resulted in an approximately 20% lower mass loss with 30% RBP. However, compared with normal concrete, RBPM suffered an increase in corrosion after carbonation. The corrosion current density and mass loss were greatly increased with increasing the RBP content. When the replacement ratio of RBP was 20%, the mortar was in low corrosion state after carbonation curing for 56 days. This was because a combination of the pozzolanic, filling, and nucleation effect of RBP contributed to a 16.28% lower cumulative pore volume and lower pH of RBPM. Considering the effect of RBP on the mechanical properties and corrosion of reinforce mortar, this study suggested a utilization ratio of 20% for RBP in the practical project. [ABSTRACT FROM AUTHOR]

The virtual load method is studied in this paper for damage assessment of beam type structures. The main advantage of this technique is that damage assessment can be accomplished by using only the vibration modes of the current structure. A series of virtual load vectors are constructed to obtain the same pure bending states for different segments of the beam. And then the curvatures of these segments loaded in pure bending are compared to identify the damage locations and extents. It was found that the proposed method is very suitable for damage assessment of those existing beam type structures.

The intersection of neutral layer and the transverse section is called neutral axis. The position of neutral-axis will be changed when the corresponding beam structure is damaged. In this work, the static loading test of recycled concrete beam is carried out to verify the damage detection method based on neutral axis position. Experimental results show that structural damage can be detected by the change of the neutral-axis position.

The flexibility-based damage identification methods have attracted much attention in structural engineering field in recent years. In this paper,three derived sensitivity methods based on structural flexibility are presented for damage identification,namely,the diagonal sensitivity,the principal eigenvector sensitivity and the unfavorable unit load distribution sensitivity. Compared with the original flexibility sensitivity technique,the effect of truncating higher-order modes can be partly reduced in the derived sensitivity methods. A three-span continuous beam was used to illustrate the feasibility and superiority of the derived sensitivity methods for structural damage detection. Results obtained by the first four modes and only the first mode are both given for comparison. When the first four modes are used,it is found that the principal eigenvector sensitivity and the flexibility sensitivity methods can achieve more accurate results than those obtained by the diagonal sensitivity and the unfavorable unit load distribution sensitivity techniques. When only the first mode is used,one can see that the principal eigenvector sensitivity and the unfavorable unit load distribution sensitivity techniques are more effective than the flexibility sensitivity and the diagonal sensitivity methods. Consequently,it is necessary to chose suitable sensitivity technique for the specific engineering problem to get satisfactory detection results.

Glioma proliferation is a multistep process during which a sequence of genetic and epigenetic alterations randomly occur to affect the genes controlling cell proliferation, cell death and genetic stability. microRNAs are emerging as important epigenetic modulators of multiple target genes, leading to abnormal cellular signaling involving cellular proliferation in cancers.In the present study, we found that expression of miR-195 was markedly downregulated in glioma cell lines and human primary glioma tissues, compared to normal human astrocytes and matched non-tumor associated tissues. Upregulation of miR-195 dramatically reduced the proliferation of glioma cells. Flow cytometry analysis showed that ectopic expression of miR-195 significantly decreased the percentage of S phase cells and increased the percentage of G1/G0 phase cells. Overexpression of miR-195 dramatically reduced the anchorage-independent growth ability of glioma cells. Furthermore, overexpression of miR-195 downregulated the levels of phosphorylated retinoblastoma (pRb) and proliferating cell nuclear antigen (PCNA) in glioma cells. Conversely, inhibition of miR-195 promoted cell proliferation, increased the percentage of S phase cells, reduced the percentage of G1/G0 phase cells, enhanced anchorage-independent growth ability, upregulated the phosphorylation of pRb and PCNA in glioma cells. Moreover, we show that miR-195 inhibited glioma cell proliferation by downregulating expression of cyclin D1 and cyclin E1, via directly targeting the 3'-untranslated regions (3'-UTR) of cyclin D1 and cyclin E1 mRNA. Taken together, our results suggest that miR-195 plays an important role to inhibit the proliferation of glioma cells, and present a novel mechanism for direct miRNA-mediated suppression of cyclin D1 and cyclin E1 in glioma.

Tissue-resident memory T (TRM) cells infiltrating solid tumors could influence tumor progression and the response to immune therapies. However, the proportion and prognostic value of TRM cells in the bone marrow (BM) of patients with acute myeloid leukemia (AML) are unclear. In this study, we used flow cytometry to assay the phenotype of 49 BM samples from patients newly diagnosed with AML (ND-AML). We found that the BM CD8 + effector memory (TEM) cells highly expressed CD69 (CD8 + TRM-like T cells), and their percentage was significantly increased in patients with ND-AML compared with that in healthy individuals (HI). The high percentage of CD8 + TRM-like subset was associated with poor overall survival in our ND-AML cohort. The Kaplan-Meier Plotter database verified a significantly reduced survival rate among patients with high expression of CD8 + TRM-like T cell characteristic genes ( CD8A , CD69 , and TOX ), especially the M4 and M5 subtypes. Phenotypic analysis revealed that the BM CD8 + TRM-like subpopulation exhibited exhausted T cell characteristics, but its high expression of CD27 and CD28 and low expression of CD57 suggested its high proliferative potential. The single-cell proteogenomic dataset confirmed the existence of TRM-like CD8 + T cells in the BM of patients with AML and verified the high expression of immune checkpoints and costimulatory molecules. In conclusion, we found that the accumulation of BM CD8 + TRM-like cells could be an immune-related survival prediction marker for patients with AML., Competing Interests: Conflict of interest: The authors declare that they have no conflict of interest., (Copyright © 2024 The Authors. Published by Wolters Kluwer Health Inc., on behalf of the Chinese Medical Association (CMA) and Institute of Hematology, Chinese Academy of Medical Sciences & Peking Union Medical College (IHCAMS).)