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The development of cracks in reinforced concrete structures can accelerate structural deterioration and reduce service life. A numerical model was established to analyse steel bar corrosion in chloride-contaminated concrete with transverse cracks. In the model, the dynamic distinction between anode and cathode regions on the steel surface is considered by introducing an empirical formula for the anodic Tafel slope related to chloride concentration. The time-dependent characteristics of the corroded region were examined using the proposed corrosion prediction model and the corrosion process of steel bars in cracked concrete was revealed. The effects of crack width and crack spacing on steel corrosion were analysed in detail in terms of the corrosion area and corrosion rate. The results showed a variation in the corrosion area adjacent to cracks over time and a positive correlation between corrosion area and the square root of time. According to the micro-cell and macro-cell contributions to the corrosion rate, the process of steel bar corrosion was determined to occur in three stages. The effects of transverse cracks on the corrosion rate were found to vary with exposure time and to depend on the control steps of the micro- or macro-cells.

With the application of wireless sensor network (WSN) in healthcare field, online sharing of medical data has attracted more and more attention. However, wearable sensor nodes in WSN are limited in energy, storage space and data processing capacity, which largely restricts their deployment in resource demand application scenarios. Fortunately, cloud storage services can enrich the capabilities of wearable sensors and provide an effective method for people to share data within a group. However, as medical data directly relates to patients' health and privacy information, ensuring the integrity and privacy of medical records stored in cloud servers becomes a key issue to be urgently solved. Many public data auditing schemes have been put forward to address the above issues. Unfortunately, most of them have security vulnerabilities or poor functionality and performance. In this paper, we come up with a secure and efficient certificateless public auditing scheme for cloud-assisted medical WSNs, which not only supports dynamic data sharing and privacy protection, but also achieves efficient group user revocation. Security analysis and performance evaluation demonstrate that our scheme significantly reduce the total computation cost while achieving a higher security level. Compared with other related schemes, our new proposal is more suitable for group user data sharing in cloud-assisted medical WSNs.

Background: Angiogenesis is a promising strategy for those with peripheral artery disease. Macrophage-centered inflammation is intended to govern the deficiency of the angiogenic response after hindlimb ischemia. However, little is known about the mechanism of macrophage activation beyond signals from cytokines and chemokines. We sought to identify a novel mechanical signal from the ischemic microenvironment that provokes macrophages and the subsequent inflammatory cascade and to investigate the potential role of Piezo-type mechanosensitive ion channels (Piezo) on macrophages during this process. Methods: Myeloid cell-specific Piezo1 (Piezo-type mechanosensitive ion channel component 1) knockout ( Piezo1 ΔMΦ ) mice were generated by crossing Piezo1 fl/fl ( LysM-Cre −/− ; Piezo1 flox/flox ) mice with LysM-Cre transgenic mice to assess the roles of Piezo1 in macrophages after hindlimb ischemia. Furthermore, in vitro studies were carried out in bone marrow–derived macrophages to decipher the underlying mechanism. Results: We found that tissue stiffness gradually increased after hindlimb ischemia, as indicated by Young’s modulus. Compared to Piezo2, Piezo1 expression and activation were markedly upregulated in macrophages from ischemic tissues in concurrence with increased tissue stiffness. Piezo1 ΔMΦ mice exhibited improved perfusion recovery by enhancing angiogenesis. Matrigel tube formation assays revealed that Piezo1 deletion promoted angiogenesis by enhancing FGF2 (fibroblast growth factor-2) paracrine signaling in macrophages. Conversely, activation of Piezo1 by increased stiffness or the agonist Yoda1 led to reduced FGF2 production in bone marrow–derived macrophages, which could be blocked by Piezo1 silencing. Mechanistically, Piezo1 mediated extracellular Ca 2+ influx and activated Ca 2+ -dependent CaMKII (calcium/calmodulin-dependent protein kinase II)/ETS1 (ETS proto-oncogene 1) signaling, leading to transcriptional inactivation of FGF2. Conclusions: This study uncovers a crucial role of microenvironmental stiffness in exacerbating the macrophage-dependent deficient angiogenic response. Deletion of macrophage Piezo1 promotes perfusion recovery after hindlimb ischemia through CaMKII/ETS1-mediated transcriptional activation of FGF2. This provides a promising therapeutic strategy to enhance angiogenesis in ischemic diseases.

By dividing encryption as online and offline stages, the online/offline encryption schemes are very suitable to lightweight equipment. For the offline stage, high-performance equipment is used for complex preprocessing calculation, and the online stage the lightweight devices only make some simple calculations. In addition, side channel attacks can disclose some secret information of the cryptosystem, which leads to the destruction of the security of the cryptography schemes. Most of the online/offline identity-based encryption schemes cannot resist side channel attacks. The paper proposes a concrete hierarchical identity-based and online/offline encryption scheme that can resist continuous leakage of secret key. By the dual system encryption technology, we prove that the given scheme is fully secure. Through key updation technology, our proposed scheme resists continual leakage of private key. The relative leakage rate of the private key can reach 1/3. In addition, the presented scheme has the hierarchical function which effectively solves the problem of heavy load in a single key generation center. The given scheme is suitable for applications in distributed environment. &nbsp

Objective. To determine the effects of circSPECC1 (hsa_circ_0000745) on the proliferation and migration of LNCaP prostate cancer cells and to explore the potential molecular mechanism. Methods. Stable circSPECC1 shRNA-expressing and circSPECC1-overexpressing LNCaP cell lines were constructed, and relative gene expression levels were determined by RT-PCR. MTT and clonogenic assays were used to assess proliferative ability while a scratch test was used to analyze cell migration. Western blotting was used to determine protein expression levels. The effects of circSPECC1 on the proliferation of LNCaP prostate cancer cells were observed in vivo. Results. circSPECC1 was found to be derived from the SPECC1 (sperm antigen with calponin homology and coiled-coil domains 1) parent gene and to form a loop. Overexpression of circSPECC1 promoted the proliferation and migration of the LNCaP cells, whereas decreased expression of circSPECC1 inhibited these properties. Overexpression of circSPECC1 promoted the expression of MMP-2, MMP-9, VEGF, vimentin, and N-cad but downregulated the expression of E-cad. Decreased expression of circSPECC1 inhibited the expression of MMP-2, MMP-9, VEGF, vimentin, and N-cad but increased the expression of E-cad. Conclusion. circSPECC1 promotes cell proliferation and migration by affecting the epithelial-mesenchymal transition of LNCaP prostate cancer cells.

In this paper, considering the multifactor influence of the knowledge dissemination process, a new ignorant-knower-spreader-forgetter (IKSF) knowledge dissemination model is proposed, which considers internalization mechanism, degradation mechanism, communication, and willingness, as well as time-varying and uncertain parameters. First, we prove that the knowledge loss equilibrium of the model is globally asymptotically stable when the basic reproduction number R 0 < 1 , and knowledge is permanent when R 0 > 1 . Next, improving the willingness of knower individuals and reducing the knowledge degradation function of spreader individuals can make the best effect of propagation; a hierarchical control strategy is designed. At the upper layer, an effective optimal control mechanism of the IKSF knowledge dissemination model is studied to provide optimal control action and minimization costs. At the lower layer, to guarantee robustness control performance and track the control targets, an intervention optimal guaranteed cost control strategy for the IKSF knowledge dissemination system with uncertain parameters is studied. Converting the controller’s design problem into a minimization problem with linear matrix inequalities, not only the impact of uncertain parameters is reduced but also the propagation effect of the knowledge dissemination model is guaranteed. Simulation results confirm our method.

Diacylglycerol is a potent element of intracellular secondary signaling cascades whose production is enhanced by cell-surface receptor agonism and function is regulated by enzymatic degradation by diacylglycerol kinases (DGKs). In T cells, stringent regulation of the activity of this second messenger maintains an appropriate balance between effector function and anergy. In this article, we demonstrate that DGKα is an indispensable regulator of TCR-mediated activation of CD8 T cells in lymphocytic choriomeningitis virus Clone 13 viral infection. In the absence of DGKα, Clone 13 infection in a murine model results in a pathologic, proinflammatory state and a multicellular immunopathologic host death that is predominantly driven by CD8 effector T cells.

Purpose In armored vehicles integrated transmissions, residual life prediction based on oil spectrum data is crucial for condition monitoring and reliability assessment. This paper aims to use the advantages of real-time and accurate prediction of binary Wiener process, the residual life prediction of clutch is studied. Design/methodology/approach First, combined with the wet clutch life test, the indicator elements Cu and Pb and the failure threshold of the residual life prediction of the clutch are extracted through the oil replacement correction of the spectral data of the whole life cycle; second, the correlation characteristics of indicating elements are analyzed by MATLAB Copula function, then the correlation function of residual life will be derived; third, according to the inverse Gaussian principle, the performance degradation mathematical models of the unary and binary Wiener processes of the above two indicator elements are established; finally, the maximum likelihood estimation method is used to estimate the parameters, and the monadic and binary performance degradation mathematical models are used to predict the residual life of the tested clutch. Findings By comparing the prediction results with the test results, with the passage of time, 81.25% of the predicted value error of the residual life prediction method based on the binary Wiener process is controlled within 20%, while 56.25% of the predicted value error of the residual life prediction method based on the unitary Wiener process is controlled within 20%. At the same time, the prediction accuracy of the binary prediction model is 2%–16.7% higher than that of the unitary prediction model. Originality/value This paper studies the residual life prediction theory of wet clutch, which can develop the theory and method of comprehensive transmission health monitoring, and provide theoretical and technical support for the construction of a reliable health management system for high-speed tracked vehicles.

Functionalization of alkenes/alkynes is a highly effective route to achieve molecular complexity. This review summarizes recent progresses on the 1,2-difunctionalization/hydrofunctionalization of unactivated alkenes/alkynes with C−S bond formation.

We present the synthesis of unsymmetrical disulfides where the homo-coupling of the thiols is inhibited by adding the thiols sequentially via rapid oxidation using bromodimethylsulfonium bromide.

Novel nano spinel-phase high-entropy oxide catalyst was synthesized by a polyol hydrothermal-calcination method, and first used in ESR hydrogen production. Self-reorganization was favored for oxygen vacancy generation promoting catalytic activity.

Silicate-based biomaterials—clinically applied fillers and promising candidates—can act as a highly biocompatible substrate for osteostimulative osteogenic cell growth in vitro and in vivo.

It is crucially important to explore the additional metal-endowed functions of supramolecular organic frameworks (SOFs) for expanding their applications.

A bilayer dressing based on aerogel/electrospun mats with self-catalytic hydrogen sulfide generation and enhanced antioxidant ability was fabricated. The dressing could reduce inflammation and accelerate wound healing.

A new probe DBTD was prepared and showed dual-channel colorimetric detection of N2H4 with a minimum detection limit of 0.438 μM which can be successfully applied to the detection of N2H4 in steam, water, cells and zebrafish.

The advanced lithium storage performance of the P-doped self-assembled V2C MXene/NiCo-LDH hybrid benefits from high capacitive contribution, high electrical conductivity, and good structural stability.

Depression is a severe psychiatric illness that causes emotional and cognitive impairment and has a considerable impact on patients' thoughts, behaviors, feelings and well-being. Moreover, methods for recognizing and treating depression are lacking in clinical practice. Electroencephalogram (EEG) signals, which objectively reflect the internal workings of the brain, is a promising and objective tool for recognizing and diagnosing of depression and enhancing clinical effects. However, previous EEG feature extraction methods have not performed well when exploring the intrinsic characteristics of highly complex and non-stationary EEG signals. To address this issue, we propose a regularization parameter-based improved intrinsic feature extraction method of EEG signals via empirical mode decomposition (EMD), which mines the intrinsic patterns in EEG signals, for depression recognition. Furthermore, our method can effectively solve the problem that EMD fails to extract intrinsic features. In this method, we first select an appropriate regularization parameter to generate the regularization matrix. Next, we calculate the sum of the matrix products of the IMFs and the regularization matrix and leverage the inverse of this matrix to extract the intrinsic features. The classification results of our method on four EEG datasets reached 0.8750, 0.8850, 0.8485 and 0.7768, respectively. In addition, compared with the iEMD method, our method requires less computational costs. These results support our claim that our method can effectively strengthen the depression recognition performance, and our method outperforms state-of-the-art feature extraction approaches.

The advancement of 5G communication technology and Internet of Things (IoT) technology has promoted the rapid development of Mobile Edge Computing (MEC). In mobile edge, all IoT devices adopt wireless communication technology. Therefore, it is particularly important to ensure the data security and the privacy of the sender in the process of data transmission. At present, a lot of researchers have proposed a large number of schemes for the authentication of the user in MEC. However, there is no effective and lightweight solution for authentication among users, edge devices and cloud server. In this paper, an efficient three-party authentication and key agreement protocol without using bilinear pairings is designed. The proposed protocol realized authentication among users, edge devices and cloud server, and at the same time, three parties conduct key agreement to obtain a common session key. The security analysis shows that our protocol is secure and meets the security attributes such as session-key security, forward secrecy. The experiment shows that the computation cost is low in this protocol. &nbsp

Nitric oxide (NO) releasing vascular graft is promising due to its merits of thromboembolism reduction and endothelialization promotion. In this study, keratin-based NO donor of S-nitrosated keratin (KSNO) was blended with poly(vinyl alcohol) (PVA) and further crosslinked with sodium trimetaphosphate (STMP) to afford PVA/KSNO biocomposite films. These films could release NO sustainably for up to 10 days, resulting in the promotion of HUVECs growth and the inhibition of HUASMCs growth. In addition, these films displayed good blood compatibility and antibacterial activity. Taken together, these films have potential applications in vascular grafts.

The exploration of multifunctional nanomedicine has prompted interest in improving glioblastoma (GBM) prognosis. In this study, we constructed tumor microenvironment (TME)-responsive magnetic therapeutic nanoparticles (BK@MTNPs) as a multifunctional drug delivery platform. It contains the following components. [Des-arg(Sheets et al., 2020 [9])]bradykinin (BK), which contributes to the transient opening of the blood-brain barrier (BBB) and targeting of GBM cells; nanoparticles (NPs) encapsulated in MTNPs, which act as an in vivo magnetic resonance (MR) imaging agent; crizotinib, which is an inhibitor of protein kinase c-Met; and the immune drug anti-PDL1 antibody. These components were loaded into BK@MTNPs for complete tumoricidal effects. Abundant glutathione in the TME can promote BK@MTNP degradation by interrupting the disulfide bonds between cysteine residues. Such BK@MTNPs support a synergistic tumoricidal effect by inducing DNA damage, activating the transcription of the tumor suppressor gene PTEN, inhibiting glioblastoma stem cell function, activating cytotoxic T lymphocytes, and reprogramming tumor-associated macrophages. BK@MTNPs showed a significant increase in antitumor activity compared with free drugs in vitro. Furthermore, in mice bearing orthotopic GBM, treatment with BK@MTNPs resulted in marked tumor inhibition and greatly extended survival time with minimal side effects. This study demonstrates the advantages of chemo-immunotherapeutic NPs accumulated in the GBM area and their effective inhibition of GBM growth, thus establishing a delivery platform to promote antitumor immunity against GBM.

The development of school education depends on the quality of the education provided, and it is a key metric for assessing the effectiveness of schools in developing talent. Building specialized, intelligent education quality monitoring (EQM) databases is crucial for speeding EQM progress in the big data era. This article examines the development of regional EQM databases in the areas of operational procedure and logical structure based on the idea of data lakes by using the development of databases for the EQM data analysis system (DAS) in Suzhou City as a case study. The goal of this study is to assist in addressing the current issues with regional EQM data processing and ensuring EQM’s successful implementation.

Many studies have explored new methods to cure acute lung injury (ALI); however, none of those methods could significantly change the high mortality rate of ALI. Shenfu is a Chinese traditional medicine that might be effective against ALI.Our study explores the therapeutic potential of Shenfu in ALI.Male C57BL/6 mice were assigned to control, lipopolysaccharide (LPS) (500 µg/100 μL per mouse), and LPS + Shenfu (30 mL/kg) groups. Shenfu (10 µL/mL) was added to LPS (10 µg/mL) treated MLE-12 cells for 48 hCompared with the ALI group, Shenfu reduced wet/dry weight ratio (19.8%, 36.2%), and reduced the IL-2 (40.9%, 61.6%), IFN-γ (43.5%, 53.3%) TNF-α (54.1%, 42.1%), IL-6 (54.8%,70%), and IL-1β (39.9%, 65.1%), reduced serum uric acid (18.8%, 48.7%) and creatinine (17.4%, 41.1%). Moreover, Shenfu enhanced cell viability (17.2%, 59.9%) and inhibited cell apoptosis (63.0%) and p38/ERK phosphorylation inTaken together, the results revealed the therapeutic effect and the underlying mechanism of Shenfu injection in an ALI in mouse model, indicating its clinical potential to treat patients with ALI.