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Recently, triboelectric generator (TEG) has attracted a lot of attention due to its high output voltage and low-cost fabrication rocess. Here, a novel cubic TEG box is designed, which has separated electrodes on different surfaces. Thanks to the specially designed structure, it can scavenge vibration energy from all directions. Firstly the device is investigated through finite element method (FEM) simulation. Then the device is evaluated by experiments. The measuremental results show that this device can generate an amount of 25 nC charge during once shake by charging a 10 nF capacitor. Besides, an output voltage about 100 V is obtained, which is able to directly light up several light-emitting diodes (LEDs) simultaneously. At last, the device is utilized as a self-powered orientation sensor, which shows explicit directivity. This work extends the applications of TEG for ambient vibration energy harvesting techniques and the self-powered orientation sensor.

Blockchain is an innovative application model that integrates distributed data storage, peer-to-peer transmission, consensus mechanisms, digital encryption technology and other computer technologies. It is decentralized, secure, and Information disclosure. In the blockchain, digital encryption technology has a core position. The security of user information and transaction data is a necessary condition for the promotion of blockchain. The development of cryptography technology promotes and restricts the further development of blockchain. This paper outlines the infrastructure of blockchain, including the data layer, network layer, consensus layer, contract layer and application layer. The principles of encryption technology is introduced briefly, such as hash function, asymmetric cryptosystem, digital signature. The application of cryptography in all levels of blockchain is analyzed, including data layer, network layer, consensus layer, etc. It shows that cryptography runs through the whole blockchain system. The existing security problems of blockchain is analyzed, and the future research direction is expected.

Imposing local boundary conditions and mitigating the surface effect at free surfaces in peridynamic (PD) models are often desired. The fictitious nodes method (FNM) “extends” the domain with a thin fictitious layer of thickness equal to the PD horizon size, and is a commonly used technique for these purposes. The FNM, however, is limited, in general, to domains with simple geometries. Here we introduce an algorithm for the mirror-based FNM that can be applied to arbitrary domain geometries. The algorithm automatically determines mirror nodes (in the given domain) of all fictitious nodes based on approximating, at each fictitious node, the “generalized” (or nonlocal) normal vector to the domain boundary. We tested the new algorithm for a peridynamic model of a classical diffusion problem with a flux singularity on the boundary. We show that other types of FNMs exhibit “pollution” of the solution far from the singularity point, while the mirror-based FNM does not and, in addition, shows a significantly faster rate of convergence to the classical solution in the limit of the horizon going to zero. The new algorithm is then used for mirror-based FNM solutions of diffusion problems in domains with curvilinear boundaries and with intersecting cracks. The proposed algorithm significantly improves the accuracy near boundaries of domains of arbitrary shapes, including those with corners, notches, and crack tips. Graphical Abstract

Normally, peridynamic (PD) models for transient heat transfer converge, in the limit of the horizon size going to zero, to the solution of the corresponding PDE-based heat transfer. However, different ways of imposing local boundary conditions have been observed to lead to some interesting properties that may deliver the classical solution at a point in space and time from a series of PD solutions obtained with relatively large horizons. Here, we use analytical derivation of PD solutions to explain how approximations introduced by the one-point Gaussian discretization in space (the so-called “meshfree” PD method) and by specific implementations of boundary conditions lead to the intersection of m -convergence curves at the exact value of the corresponding classical model solution. This leads to a strategy of approximating the local solution better with a sequence of PD models that use relatively large horizons compared to a PD model that uses a small horizon. We analyze this property for transient heat conduction in homogeneous and heterogeneous bars. We find that material interfaces influence the intersection of m -convergence curves for transient heat conduction in a 1D heterogeneous bar.

Fracture and corrosion are two major causes of structure failure. They can interact with each other, leading to faster material degradation. They are also under the influence of environmental conditions. The corrosion rate highly depends on the transportation rate of involving substances, while the fracture can be accelerated significantly due to fluid flow. These complex mechanisms involved in structure failure have troubled classical models for decades. The peridynamic (PD) theory introduced in 2000 has shown great potential in modeling such problems. In this work, we develop novel PD models for fracture, corrosion, mass transport, and viscous flow, which are building blocks to make comprehensive predictions on structure failure. We first introduce a partially-homogenized PD model for concrete fracture. The model links microscale information to macroscale fracture behavior, while costing the same as a fully homogenized model. This model successfully predicts corrosion-induced fracture in concretes with a single or multiple rebars. We then develop a new PD corrosion model which can update the distribution of corrosion rates along arbitrary metal surface, particularly useful for simulating galvanic corrosion. We couple the new PD corrosion model with the PD fracture model and solve a problem under combined electro-chemical attack and mechanical forces to demonstrate the capability of PD models. We also construct PD models for transient advection-diffusion and viscous flow from fundamental conservation principles. The constructive approach in deriving these models allows for future modeling of complex fluid-structure interaction problems in which solid degradation takes place, such as erosion-corrosion and hydraulic fracture. In PD models, boundary conditions (BCs) are naturally nonlocal, but usually only local BCs are available from measurements. The existing mirror-type fictitious nodes method (FNM) can convert local BCs to nonlocal ones, but its application is limited to domains with simple geometries. We introduce a new algorithm to make the mirror-type FNM work autonomously for domains with arbitrary geometries. The algorithm developed is general and should also work for any type of peridynamic model, including corrosion, fracture, and fluid-structure interactions.

Arterial stiffness has been recognized as a predictor of cardiovascular and all-cause mortality in hypertensive patients. However, the impact of continuous positive airway pressure (CPAP) on arterial stiffness in patients with OSA and hypertension remains inconclusive. We performed a meta-analysis to determine whether effective CPAP therapy could decrease arterial stiffness. Two reviewers independently searched PubMed, Embase, Web of Science and Cochrane Library prior to March 5, 2015. Information on characteristics of subjects, study design and pre- and post-CPAP treatment of arterial stiffness was extracted for analysis. Standardized mean difference (SMD) was used to analyze the summary estimates for CPAP therapy. Three articles with 186 patients were included in this meta-analysis, including two observational studies and one randomized controlled study. The meta-analysis showed that CPAP was associated with a statistically significant decrease in arterial stiffness in patients with OSA and hypertension (SMD = −0.65, 95 % confidence interval (CI) = −1.14 to −0.16, z = 2.60, p = 0.009). Our meta-analysis suggested that CPAP among OSA and hypertensive patients was significantly associated with a decrease in arterial stiffness. Further prospective large-scale multicenter RCTs are needed to explore the precise impact of CPAP therapy on arterial stiffness in patients with OSA and hypertension.

Dysregulation of macrophage autophagy plays a critical role in sepsis-induced acute lung injury (ALI); however, its underlying mechanism remains unclear. In this study, we aimed to identify the regulatory pathway involving the PIK3C3-MAPK14 signaling axis that drives ALI progression by controlling autophagy and macrophage polarization. Using machine learning transcriptomic analysis, MAPK14 was identified as a core gene associated with ALI, and multi-omics integration confirmed its upregulated expression in ALI tissues. MAPK14 localization to pro-inflammatory macrophages was determined using single-cell sequencing. Furthermore, we observed a significant positive correlation between MAPK14 and autophagy-related genes. Molecular docking and kinetic simulations revealed high-affinity interactions between PIK3C3 and MAPK14 (ΔG-bind = -127.722 ± 33.269 kJ/mol). In vitro experiments followed by Western Blot(WB) and RT-q polymerase chain reaction (PCR) assays demonstrated that lipopolysaccharide stimulation upregulated MAPK14 expression through downregulation of PIK3C3 expression, resulting in impaired autophagic flux (LC3-II/Ⅰ↓, TOM20↑, P62↑, HSP60↑). Flow cytometry and enzyme-linked immunosorbent assay (ELISA) confirmed a shift toward pro-inflammatory (M1) macrophage polarization. RNA pull-down assay directly captured the PIK3C3-MAPK14 complex, and functional validation showed that PIK3C3 overexpression significantly inhibited MAPK14 protein expression, whereas PIK3C3 knockdown enhanced it. In conclusion, targeting the PIK3C3-MAPK14 axis is a promising therapeutic strategy for ALI.

Retinoids, defined as synthetic or natural derivatives of vitamin A, have been extensively studied as anti-aging molecules that are widely applied in cosmetics. However, due to their physicochemical property, retinoids are highly unstable and extremely sensitive to light, oxygen, and temperature. Moreover, topical application of retinoids often leads to cutaneous irritation. These instabilities and irritant properties of retinoids limit their application in cosmetic and pharmaceutical products. Our study aimed to provide a systematic review to summarize the mechanisms underlying the instability and irritant properties of retinoids, as well as recent developments in addressing these challenges. A comprehensive PubMed search was conducted using the following keywords: retinoids, chemical instability, skin irritation, retinoid derivatives, nano lipid-based carriers, liposomes, penetration-enhancer vesicles, ethosomes, niosomes, nanoemulsions, solid lipid nanoparticles, vitamins, soothing and hydrating agents, antioxidants and metal chelator and retinol combinations. Relevant researches published between 1968 and 2023 and studies related to these reports were reviewed. The development of new retinoid derivatives, the utilization of new delivery systems like nano lipid-based carriers and the combination with other compounds like vitamins, soothing agents, antioxidants and metal chelator have been explored to improve the stability, bioavailability, and toxicity of the retinoid family. Through advancements in formulation techniques, structure modification of retinoid derivatives and development of novel nano lipid-based carriers, the chemical instability and skin irritation of retinoids has been mitigated, ensuring their efficacy and potency over extended periods.

Osteoarthritis (OA) is a degenerative disease that often causes cartilage lesions and even osteochondral damage. Osteochondral defects induced by OA are accompanied by an inflammatory arthrosis microenvironment with overproduced reactive oxygen species (ROS), resulting in the exacerbation of defects and difficulty regenerating osteochondral tissues. Therefore, it is urgently needed to develop osteochondral scaffolds that can not only promote the integrated regeneration of cartilage and subchondral bone, but also possess ROS‐scavenging ability to protect tissues from oxidative stress. Herein, zinc‐cobalt bimetallic organic framework (Zn/Co‐MOF) functionalized bioceramic scaffolds are designed for repairing osteochondral defects under OA environment. By functionalizing Zn/Co‐MOF on the 3D‐printed beta‐tricalcium phosphate (β‐TCP) scaffolds, the Zn/Co‐MOF functionalized β‐TCP (MOF‐TCP) scaffolds with broad‐spectrum ROS‐scavenging ability are successfully developed. Benefiting from its catalytic active sites and degradation products, Zn/Co‐MOF endows the scaffolds with excellent antioxidative and anti‐inflammatory properties to protect cells from ROS invasion, as well as dual‐bioactivities of simultaneously inducing osteogenic and chondrogenic differentiation in vitro. Furthermore, in vivo results confirm that MOF‐TCP scaffolds accelerate the integrated regeneration of cartilage and subchondral bone in severe osteochondral defects. This study offers a promising strategy for treating defects induced by OA as well as other inflammatory diseases. Zinc‐cobalt bimetallic organic framework (Zn/Co‐MOF) functionalized bioceramic scaffolds are developed by functionalizing Zn/Co‐MOF on the 3D‐printed beta‐tricalcium phosphate (β‐TCP) scaffolds. The Zn/Co‐MOF functionalized β‐TCP (MOF‐TCP) scaffolds possess the ability to protect cells from reactive oxygen species invasion, the immunomodulatory activity, as well as the dual bioactivity of simultaneously promoting osteogenesis and chondrogenesis, exhibiting great potential for treating osteochondral defects.

Ultraviolet B (UVB) rays are a type of ultraviolet radiation emitted by the sun, primarily responsible for skin photodamage. These rays mainly affect the epidermis, leading to direct damage to DNA and contributing to skin cancer development. Retinol and its derivatives are effective in combating skin aging and photodamage, but they often cause skin intolerance, limiting their use despite their potent effects. Therefore, investigating optimal compositions of retinoids is essential to enhance their efficacy against photodamage. In this study, we investigated the synergistic effects of retinol (ROL) and retinyl palmitate (RPalm) in alleviating UVB-induced DNA damage in human keratinocytes (HaCaT) and reconstructed human epidermis. The ROL+RPalm combination was applied after UVB exposure. We utilized bulk mRNA sequencing, comet assays, Western blotting, immunofluorescence, and flow cytometry to evaluate the level of DNA damage and repair. The application of the ROL+RPalm combination significantly reduced inflammation and apoptosis while promoting collagen synthesis compared to individual treatments with ROL or RPalm. Our findings indicated that the ROL+RPalm synergy primarily mediates DNA damage repair. Additionally, we elucidated that the molecular mechanism involves the activation of RARβ, which triggers the ATM-CHK2-p53 signaling pathway and increases the expression of homologous recombination (HR)-associated repair genes. This combination of ROL and RPalm presents a potential therapeutic strategy for UVB-induced photodamage and emphasizes the synergistic effects in alleviating UVB-induced DNA damage.