Search Results (21)

E-skin is an integrated electronic system that can mimic the perceptual ability of human skin. Traditional analysis methods struggle to handle complex e-skin data, which include time series and multiple patterns, especially when dealing with intricate signals and real-time responses. Recently, deep learning techniques, such as the convolutional neural network, recurrent neural network, and transformer methods, provide effective solutions that can automatically extract data features and recognize patterns, significantly improving the analysis of e-skin data. Deep learning is not only capable of handling multimodal data but can also provide real-time response and personalized predictions in dynamic environments. Nevertheless, problems such as insufficient data annotation and high demand for computational resources still limit the application of e-skin. Optimizing deep learning algorithms, improving computational efficiency, and exploring hardware–algorithm co-designing will be the key to future development. This review aims to present the deep learning techniques applied in e-skin and provide inspiration for subsequent researchers. We first summarize the sources and characteristics of e-skin data and review the deep learning models applicable to e-skin data and their applications in data analysis. Additionally, we discuss the use of deep learning in e-skin, particularly in health monitoring and human–machine interactions, and we explore the current challenges and future development directions. Full article

Humans possess an innate ability to perceive a wide range of objects through touch, which allows them to interact effectively with their surroundings. Similarly, tactile perception in artificial sensory systems enables the acquisition of object properties, human physiological signals, and environmental information. Biomimetic tactile sensors, as an emerging sensing technology, draw inspiration from biological systems and exhibit high sensitivity, rapid response, multimodal perception, and stability. By mimicking biological mechanisms and microstructures, these sensors achieve precise detection of mechanical signals, thereby paving the way for advancements in tactile sensing applications. This review provides an overview of key sensing mechanisms, microstructure designs, and advanced fabrication techniques of biomimetic tactile sensors. The system architecture design of biomimetic tactile sensing systems is also explored. Furthermore, the review highlights significant applications of these sensors in recent years, including texture recognition, human health detection, and human–machine interaction. Finally, the key challenges and future development prospects related to biomimetic tactile sensors are discussed. Full article

Acute kidney injury (AKI) and chronic kidney disease (CKD) represent two frequently observed clinical conditions. AKI is characterized by an abrupt decrease in glomerular filtration rate (GFR), generally associated with elevated serum creatinine (sCr), blood urea nitrogen (BUN), and electrolyte imbalances. This condition usually persists for approximately a week, causing a transient reduction in kidney function. If these abnormalities continue beyond 90 days, the condition is redefined as chronic kidney disease (CKD) or may advance to end-stage renal disease (ESRD). Recent research increasingly indicates that maladaptive repair mechanisms after AKI significantly contribute to the development of CKD. Thus, implementing early interventions to halt the progression from AKI to CKD has the potential to markedly improve patient outcomes. Although considerable research has been conducted, the exact mechanisms linking AKI to CKD are complex, and effective treatments remain limited. Kidney function is influenced by circadian rhythms, with the circadian gene Bmal1 being vital in managing these cycles. Recent research indicates that Bmal1 is significantly involved in the progression of both AKI and CKD. In this study, we conducted a retrospective analysis of Bmal1’s role in AKI and CKD, reviewed recent research advancements, and investigated how Bmal1 influences the pathological mechanisms underlying the progression from AKI to CKD. Additionally, we highlighted gaps in the existing research and examined the potential of Bmal1 as a therapeutic target in kidney disease management. This work aims to provide meaningful insights for future studies on the role of the circadian gene Bmal1 in the transition from AKI to CKD, with the goal of identifying therapeutic approaches to mitigate kidney disease progression. Full article

The rise of the Internet of things has catalyzed extensive research in the realm of flexible wearable sensors. In comparison with conventional sensor power supply methods that are reliant on external sources, self-powered sensors offer notable advantages in wearable comfort, device structure, and functional expansion. The energy-harvesting modes dominated by piezoelectric nanogenerators (PENGs), triboelectric nanogenerators (TENGs), and pyroelectric nanogenerators (PyENGs) create more possibilities for flexible self-powered sensors. This paper meticulously examines the progress in flexible self-powered devices harnessing TENG, PENG, and PyENG technologies and highlights the evolution of these sensors concerning the material selection, pioneering manufacturing techniques, and device architecture. It also focuses on the research progress of sensors with composite power generation modes. By amalgamating pivotal discoveries and emerging trends, this review not only furnishes a comprehensive portrayal of the present landscape but also accentuates avenues for future research and the application of flexible self-powered sensor technology. Full article

Additive manufacturing, commonly known as 3D printing technology, has become a prominent topic of research globally in recent years and is playing an increasingly important role in various industries. Particularly within the healthcare sector, the use of 3D printing technology is gaining prominence, with a special focus on the manufacturing and application of dental implants. As research in this field progresses, the preparation methods, material selection, and technological innovations for dental implants are evolving, promising a future where the manufacturing process of dental implants becomes even more refined and efficient. Through thorough research in materials science, it is possible to develop dental implant materials that have better biocompatibility with the human body and improved mechanical properties. Additionally, advancements in surface modification technology can further enhance the strength and stability of the bond between dental implants and bone tissue. These advancements not only expand treatment options for patients but also greatly improve the long-term success rate of dental implants. In the field of dental implants, the success of the implant depends on the interactions between the materials used, the cells involved, and the bone tissue. Therefore, there is an urgent need to explore the molecular mechanisms of such interactions in depth. In this study, we provide a comprehensive review of the application of 3D printing technology in the fabrication of dental implants. This includes an examination of the process methods, surface coating technology, and a comparison of the shapes and structures of different dental implants, along with their advantages and disadvantages. Furthermore, this paper analyzes the intrinsic mechanisms of successful dental implant placement in clinical practice, and it highlights the latest progress in the clinical application of 3D-printed dental implants. Undeniably, the use of 3D-printed dental implants not only offers patients more precise and personalized treatment plans but also brings revolutionary changes to the development of the medical industry. Full article

This study undertakes a comprehensive examination of the intricate link between diet nutrition, age, and metabolic syndrome (MetS), utilizing advanced artificial intelligence methodologies. Data from the National Health and Nutrition Examination Survey (NHANES) spanning from 1999 to 2018 were meticulously analyzed using machine learning (ML) techniques, specifically extreme gradient boosting (XGBoost) and the proportional hazards model (COX). Using these analytic methods, we elucidated a significant correlation between age and MetS incidence and revealed the impact of age-specific dietary patterns on MetS. The study delineated how the consumption of certain dietary components, namely retinol, beta-cryptoxanthin, vitamin C, theobromine, caffeine, lycopene, and alcohol, variably affects MetS across different age demographics. Furthermore, it was revealed that identical nutritional intakes pose diverse pathogenic risks for MetS across varying age brackets, with substances such as cholesterol, caffeine, and theobromine exhibiting differential risks contingent on age. Importantly, this investigation succeeded in developing a predictive model of high accuracy, distinguishing individuals with MetS from healthy controls, thereby highlighting the potential for precision in dietary interventions and MetS management strategies tailored to specific age groups. These findings underscore the importance of age-specific nutritional guidance and lay the foundation for future research in this area. Full article

As a biomedical material, porous titanium alloy has gained widespread recognition and application within the field of orthopedics. Its remarkable biocompatibility, bioactivity, and mechanical properties establish it as a promising material for facilitating bone regeneration. A well-designed porous structure can lower the material’s modulus while retaining ample strength, rendering it more akin to natural bone tissue. The progression of additive manufacturing (AM) technology has significantly propelled the advancement of porous implants, simplifying the production of such structures. AM allows for the customization of porous implants with various shapes and sizes tailored to individual patients. Additionally, it enables the design of microscopic-scale porous structures to closely mimic natural bone, thus opening up avenues for the development of porous titanium alloy bone implants that can better stimulate bone regeneration. This article reviews the research progress on the structural design and preparation methods of porous titanium alloy bone implants, analyzes the porous structure design parameters that affect the performance of the implant, and discusses the application of porous medical titanium alloys. By comparing the effects of the parameters of different porosity, pore shape, and pore size on implant performance, it was concluded that pore diameters in the range of 500~800 μm and porosity in the range of 70%–90% have better bone-regeneration effects. At the same time, when the pore structure is a diamond, rhombohedral, or cube structure, it has better mechanical properties and bone-regeneration effects, providing a reference range for the application of clinical porous implants. Full article

The advent of three-dimensional (3D) printing technology has revolutionized the production of customized titanium (Ti) alloy implants. The success rate of implantation and the long-term functionality of these implants depend not only on design and material selection but also on their surface properties. Surface modification techniques play a pivotal role in improving the biocompatibility, osseointegration, and overall performance of 3D-printed Ti alloy implants. Hence, the primary objective of this review is to comprehensively elucidate various strategies employed for surface modification to enhance the performance of 3D-printed Ti alloy implants. This review encompasses both conventional and advanced surface modification techniques, which include physical–mechanical methods, chemical modification methods, bioconvergence modification technology, and the functional composite method. Furthermore, it explores the distinct advantages and limitations associated with each of these methods. In the future, efforts in surface modification will be geared towards achieving precise control over implant surface morphology, enhancing osteogenic capabilities, and augmenting antimicrobial functionality. This will enable the development of surfaces with multifunctional properties and personalized designs. By continuously exploring and developing innovative surface modification techniques, we anticipate that implant performance can be further elevated, paving the way for groundbreaking advancements in the field of biomedical engineering. Full article

The potential association between calcium oxalate stones and renal fibrosis has been extensively investigated; however, the underlying mechanisms remain unclear. Ferroptosis is a novel form of cell death characterized by iron-dependent lipid peroxidation and regulated by acyl coenzyme A synthase long-chain family member 4 (ACSL4). Yes-associated protein (YAP), a transcriptional co-activator in the Hippo pathway, promotes ferroptosis by modulating ACSL4 expression. Nevertheless, the involvement of YAP–ACSL4 axis-mediated ferroptosis in calcium oxalate crystal deposition-induced renal fibrosis and its molecular mechanisms have not been elucidated. In this study, we investigated ACSL4 expression and ferroptosis activation in the kidney tissues of patients with calcium oxalate stones and in mice using single-cell sequencing, transcriptome RNA sequencing, immunohistochemical analysis, and Western blot analysis. In vivo and in vitro experiments demonstrated that inhibiting ferroptosis or ACSL4 mitigated calcium oxalate crystal-induced renal fibrosis. Furthermore, YAP expression was elevated in the kidney tissues of patients with calcium oxalate stones and in calcium oxalate crystal-stimulated human renal tubular epithelial cell lines. Mechanistically, in calcium oxalate crystal-stimulated human renal tubular epithelial cell lines, activated YAP translocated to the nucleus and enhanced ACSL4 expression, consequently inducing cellular ferroptosis. Moreover, YAP silencing suppressed ferroptosis by downregulating ACSL4 expression, thereby attenuating calcium oxalate crystal-induced renal fibrosis. Conclusively, our findings suggest that YAP–ACSL4-mediated ferroptosis represents an important mechanism underlying the induction of renal fibrosis by calcium oxalate crystal deposition. Targeting the YAP–ACSL4 axis and ferroptosis may therefore hold promise as a potential therapeutic approach for preventing renal fibrosis in patients with kidney stones. Full article

Wearable sensors open unprecedented opportunities for long-term health monitoring and human–machine interaction. Electrospinning is considered to be an ideal technology to produce functional structures for wearable sensors because of its unique merits to endow devices with highly designable functional microstructures, outstanding breathability, biocompatibility, and comfort, as well as its low cost, simple process flow, and high productivity. Recent advances in wearable sensors with one-, two-, or three-dimensional (1D, 2D, or 3D) electrospun microstructures have promoted various applications in healthcare, action monitoring, and physiological information recognition. Particularly, the development of various novel electrospun microstructures different from conventional micro/nanofibrous structures further enhances the electrical, mechanical, thermal, and optical performances of wearable sensors and provides them with multiple detection functions and superior practicality. In this review, we discuss (i) the principle and typical apparatus of electrospinning, (ii) 1D, 2D, and 3D electrospun microstructures for wearable sensing and their construction strategies and physical properties, (iii) applications of microstructured electrospun wearable devices in sensing pressure, temperature, humidity, gas, biochemical molecules, and light, and (iv) challenges of future electrospun wearable sensors for physiological signal recognition, behavior monitoring, personal protection, and health diagnosis. Full article

Microfluidics has recently received more and more attention in applications such as biomedical, chemical and medicine. With the development of microelectronics technology as well as material science in recent years, microfluidic devices have made great progress. Porous structures as a discontinuous medium in which the special flow phenomena of fluids lead to their potential and special applications in microfluidics offer a unique way to develop completely new microfluidic chips. In this article, we firstly introduce the fabrication methods for porous structures of different materials. Then, the physical effects of microfluid flow in porous media and their related physical models are discussed. Finally, the state-of-the-art porous microfluidic chips and their applications in biomedicine are summarized, and we present the current problems and future directions in this field. Full article

Objective: Polyetheretherketone (PEEK) is widely used as an orthopedic implant material owing to its good biocompatibility and mechanical strength; however, PEEK implants are biologically inert, resulting in suboptimal cellular responses after implantation. The aim of this study was to enhance the biological activity of PEEK through sulfonation treatment. Methods: In this study, distal phalangeal implants of PEEK were customized by fused deposition modeling (FDM) printing technology and soaked in concentrated sulfuric acid at different times to obtain sulfonated PEEK (SPEEK). The groups were divided into five groups according to the sulfonation time as follows: 0 min (control group), 1 min (group SPEEK1), 2 min (group SPEEK2), 4 min (group SPEEK4), and 8 min (group SPEEK8). Then the physicochemical characteristics of implants were determined by SEM, XRD, EDS, etc. The implants were co-cultured with stem cells from human exfoliated deciduous teeth (SHED), and then the cell proliferation, adhesion, alkaline phosphatase (ALP) activity, and alizarin red staining were performed to detect the biological activity, biocompatibility, and osteogenic activity of the SPEEK implants. Results: The sulfonation time range of 1 to 8 min could promote the formation of micropores on the surface of PEEK implants, while slightly affecting the composition and compression performance of the implants. Compared with the control group, the hydrophilicity of PEEK materials was not improved after sulfonation treatment. Tests for adhesion and proliferation of SHED indicated that SPEEK2 showed superior biocompatibility. Furthermore, ALP activity and semi-quantitative analysis of Alizarin red staining showed that the osteogenic activity of SPEEK2 phalanges exhibited significantly stronger osteogenic activity than the other groups. Conclusions: The method presented here provides a promising approach to improve the surface bioactivity of PEEK implants prepared by FDM, providing a shred of primary evidence to support the application of SPEEK in orthopedics. Full article

The dry matter test of mango has important practical significance for the quality classification of mango. Most of the common fruit and vegetable quality nondestructive testing methods based on fluorescence hyperspectral imaging technology use a single algorithm in algorithms such as Uninformative Variable Elimination (UVE), Random Frog (RF), Competitive Adaptive Reweighted Sampling (CARS) and Continuous Projection Algorithm (SPA) to extract feature spectral variables, and the use of these algorithms alone can easily lead to the insufficient stability of prediction results. In this regard, a nondestructive detection method for the dry matter of mango based on hyperspectral fluorescence imaging technology was carried out. Taking the ‘Keitt’ mango as the research object, the mango samples were numbered in sequence, and their fluorescence hyperspectral images in the wavelength range of 350–1100 nm were collected, and the average spectrum of the region of interest was used as the effective spectral information of the sample. Select SPXY algorithm to divide samples into a calibration set and prediction set, and select Orthogonal Signal Correction (OSC) as preprocessing method. For the preprocessed spectra, the primary dimensionality reduction (UVE, SPA, RF, CARS), the primary combined dimensionality reduction (UVE + RF, CARS + RF, CARS + SPA), and the secondary combined dimensionality reduction algorithm ((CARS + SPA)-SPA, (UVE + RF)-SPA) and other 12 algorithms were used to extract feature variables. Separately constructed predictive models for predicting the dry matter of mangoes, namely, Support Vector Regression (SVR), Extreme Learning Machine (ELM), and Back Propagation Neural Network (BPNN) model, were used; The results show that (CARS + RF)-SPA-BPNN has the best prediction performance for mango dry matter, its correlation coefficients were R_C² = 0.9710, R_P² = 0.9658, RMSEC = 0.1418, RMSEP = 0.1526, this method provides a reliable theoretical basis and technical support for the non-destructive detection, and precise and intelligent development of mango dry matter detection. Full article

Trauma and bone loss from infections, tumors, and congenital diseases make bone repair and regeneration the greatest challenges in orthopedic, craniofacial, and plastic surgeries. The shortage of donors, intrinsic limitations, and complications in transplantation have led to more focus and interest in regenerative medicine. Structures that closely mimic bone tissue can be produced by this unique technology. The steady development of three-dimensional (3D)-printed bone tissue engineering scaffold therapy has played an important role in achieving the desired goal. Bioceramic scaffolds are widely studied and appear to be the most promising solution. In addition, 3D printing technology can simulate mechanical and biological surface properties and print with high precision complex internal and external structures to match their functional properties. Inkjet, extrusion, and light-based 3D printing are among the rapidly advancing bone bioprinting technologies. Furthermore, stem cell therapy has recently shown an important role in this field, although large tissue defects are difficult to fill by injection alone. The combination of 3D-printed bone tissue engineering scaffolds with stem cells has shown very promising results. Therefore, biocompatible artificial tissue engineering with living cells is the key element required for clinical applications where there is a high demand for bone defect repair. Furthermore, the emergence of various advanced manufacturing technologies has made the form of biomaterials and their functions, composition, and structure more diversified, and manifold. The importance of this article lies in that it aims to briefly review the main principles and characteristics of the currently available methods in orthopedic bioprinting technology to prepare bioceramic scaffolds, and finally discuss the challenges and prospects for applications in this promising and vital field. Full article

Objective: The objective of this study is to compare the bone induction of five kinds of calcium phosphate (Ca-P) biomaterials implanted in mice and explore the vascularization and particle-size-related osteoinductive mechanism. Methods: The following five kinds of Ca-P biomaterials including hydroxyapatite (HA) and/or tricalcium phosphate (TCP) were implanted in the muscle of 30 BALB/c mice (n = 6): 20 nm HA (20HA), 60 nm HA (60HA), 12 µm HA (12HA), 100 nm TCP (100TCP) and 12 µm HA + 100 nm TCP (HATCP). Then, all animals were put on a treadmill to run 30 min at a 6 m/h speed each day. Five and ten weeks later, three mice of each group were killed, and the samples were harvested to assess the osteoinductive effects by hematoxylin eosin (HE), Masson’s trichrome and safranine–fast green stainings, and the immunohistochemistry of the angiogenesis and osteogenesis markers CD31 and type I collagen (ColI). Results: The numbers of blood vessels were 139 $\pm$ $29, 118 \pm 25, 78 \pm 15, 65 \pm 14$ in groups HATCP, 100TCP, 60HA and 20HA, respectively, which were significantly higher than that of group 12HA (12 $\pm$ 5) in week 5 (p < 0.05). The area percentages of new bone tissue were (7.33 $\pm$ 1.26)% and (8.49 $\pm 1.38)\%$ in groups 100TCP and HATCP, respectively, which were significantly higher than those in groups 20HA (3.27 $\pm 0.38)\%$ and 60HA (3.43 $\pm 0.27)\%$ (p < 0.05); however, no bone tissue was found in group 12HA 10 weeks after transplantation. The expression of CD31 was positive in new blood vessels, and the expression of ColI was positive in new bone tissue. Conclusions: Nanoscale Ca-P biomaterials could induce osteogenesis in mice muscle, and the osteoinductive effects of TCP were about 124% higher than those of 20HA and 114% higher than those of 60HA. The particle size of the biomaterials affected angiogenesis and osteogenesis. There was a positive correlation between the number of blood vessels and the area percentage of new bone tissue; therefore, osteoinduction is closely related to vascularization. Our results provide an experimental basis for the synthesis of calcium–phosphorus matrix composites and for further exploration of the osteoinductive mechanism. Full article