Search Results (215)

Deployable thin-film antennas deliver large aperture gains and high stowage efficiency for spaceborne phased arrays but suffer wrinkling-induced planarity loss and radiation distortion. To bridge the lack of electromechanical coupling models for tensioned thin-film patch antennas, we present a unified framework combining structural deformation and electromagnetic simulation. We derive a coupling model capturing the increased bending stiffness of stepped-thickness membranes, formulate a wrinkling analysis algorithm to compute tension-induced displacements, and fit representative unit-cell deformations to a dual-domain displacement model. Parametric studies across stiffness ratios confirm the framework’s ability to predict shifts in pattern, gain, and impedance due to wrinkling. This tool supports the optimized design of wrinkle-resistant thin-film phased arrays for reliable, high-performance space communications. Full article

This study investigates the shell hydroforming of 1.2 mm-thick AA5052 aluminum alloy sheets to produce hemispherical domes which possess inherent spatial symmetry about their central axis. Shell hydroforming is widely used in fabricating lightweight, high-strength components for aerospace, automotive, and energy applications. The forming process was driven by a spatially symmetrical internal pressure distribution applied uniformly across the blank to maintain balanced deformation and minimize geometrical distortion. Experimental trials aimed at achieving a dome depth of 50 mm revealed wrinkle formation at the blank periphery caused by circumferential compressive stresses symmetrical in nature with respect to the dome’s central axis. To better understand the forming behavior, a validated 3D finite element (FE) model was developed, capturing key phenomena such as material flow, strain rate evolution, hydrostatic stress distribution, and wrinkle development under symmetric boundary conditions. The effects of the internal pressure (IP), blank holding force (BHF), coefficient of friction (CoF), and flange radius (FR) were systematically studied. A strain rate of 0.1 s⁻¹ in the final stage improved material flow, while a symmetric tensile hydrostatic stress of 160 MPa facilitated dome expansion. Although tensile stresses can induce void growth, the elevated strain rate helped suppress it. An optimized parameter set of IP = 5.43 MPa, BHF = 140 kN, CoF = 0.04, and FR = 5.42 mm led to successful formation of the 50 mm dome with 19.38% thinning at the apex. Internal pressure was identified as the most critical factor influencing symmetric formability. A process window was established to predict symmetric failure modes such as wrinkling and bursting. Full article

Squalane (SQ, a saturated, sebum-mimetic hydrocarbon), oleic acid (OA, a monounsaturated fatty acid), and linoleic acid (LA, a polyunsaturated essential fatty acid) belong to the category of “lipids and fats” in cosmetic materials, and are widely employed as skin-conditioning emollients. However, they present differences in UV stress. In this study, we compared their effects on UV-induced oxidative damage, inflammation, and lipid metabolism using a mouse model and human sebaceous gland cells (SZ95). Results showed that 10% SQ did not worsen oxidative damage or inflammation after 6 weeks of UV exposure. In contrast, the 5% and 10% OA/LA groups showed increased skin wrinkling (p < 0.01), epidermal thickening (p < 0.05), and sebaceous gland atrophy. Transcriptome analysis indicated OA/LA upregulated arachidonic acid-related cytokine pathways (PTGS2/IL-1β; p < 0.001). In SZ95 cells, 0.006% OA/LA significantly increased lipid droplet formation (p < 0.001), free fatty acid (FFA) levels (p < 0.001), and pro-inflammatory gene expression (p < 0.001). Conversely, SQ neither promoted lipid droplet/FFA secretion nor induced oxidative stress. These findings suggest that high concentrations of unsaturated fatty acids in skincare may worsen lipid dysregulation and inflammation, while formulations based on saturated hydrocarbons like SQ could provide superior photoaging management by stabilizing skin barrier function. Full article

Facial wrinkles are a key indicator of aging and hold significant importance in skincare, cosmetics, and cosmetology. Their formation is closely linked to mechanical deformation, yet the underlying processes remain complex. This study integrates the Facial Action Coding System (FACS) with three-dimensional digital image correlation (3D-DIC) to dynamically capture and quantitatively analyze skin deformation during facial expression. Principal strains and their orientation are introduced as important parameters to investigate the relationship between mechanical behavior and wrinkle formation. To further explore these interactions, a four-layer finite element (FE) model incorporating a muscle layer is developed, simulating muscle contraction and its influence on skin deformation. The findings provide a mechanobiological framework for understanding wrinkle formation and may inspire the development of strain-sensitive sensors for real-time detection of microstructural deformations. Full article

Previous models of extraocular mechanics have often assumed isotropic properties for ocular tissues, despite evidence indicating anisotropy in the optic nerve sheath (ONS). To investigate this further, we developed a finite element model (FEM) of horizontal eye rotation using MRI data from a living subject with normal tension glaucoma. Mechanical properties were derived from tensile tests on 17 post-mortem human eyes, revealing previously unrecognized anisotropic characteristics in the ONS. We simulated ±32° horizontal eye rotations and compared isotropic versus anisotropic ONS properties using the Holzapfel model. Strain distributions in the optic nerve (ON) were analyzed using ABAQUS 2024 software. During 32° adduction, stress and strain were concentrated at the ONS-sclera junction, reaching 8 MPa and 40% with isotropic properties, and 15 MPa and 30% with anisotropic properties. In contrast, during 32° abduction, stress was lower and strain was higher in the isotropic case (6 MPa and 30%) compared to the anisotropic case (12 MPa and 25%). Increased intraocular and intracranial pressures had minimal impact on the mechanical responses. These findings suggest that the anisotropic properties of the ONS increase stress concentration at the optic disc while reducing strain during eye movements, offering new insights into ocular biomechanics. A novel phenomenon emerged from the simulations: during larger ductions, the peripapillary Bruch’s membrane is predicted to wrinkle, forming undulations with an approximately 20 μm amplitude and 100 μm wavelength at its interface with the retina and choroid. Full article

To solve the manufacturing problem of the efficient removal of multi-scale surface defects (wrinkles, cracks, scratches, etc.) on the inner wall of MP35N cobalt–chromium alloy vascular stents, this study proposes a collaborative optimization strategy of magnetic abrasive polishing (MAF) based on a new type of magnetic abrasive. In response to the unique requirements for the inner wall processing of high aspect ratio microtubes, metal-based Al₂O₃ magnetic abrasives with superior performance were prepared by the plasma melt powder spraying method. A special MAF system for the inner wall of the bracket was designed and constructed. The four-factor and three-level Box–Behnken response surface method was adopted to analyze the influences and interactions of tube rotational speed, magnetic pole feed rate, abrasive filling amount, and processing clearance on surface roughness (Ra). The significance order of each parameter for Ra is determined as follows: processing clearance > tube rotational speed > abrasive filling amount > magnetic pole feed rate. Using the established model and multiple regression equations, the optimal parameters were determined as follows: a tube rotational speed of 600 r/min, a magnetic pole feed rate of 150 mm/min, an abrasive filling amount of 0.50 g, and a processing clearance of 0.50 mm. The optimized model predicted an Ra value of 0.104 μm, while the average Ra value verified experimentally was 0.107 μm, with the minimum error being 2.9%. Compared with the initial Ra of 0.486 μm, directly measured by the ultra-depth-of-field 3D microscope of model DSX1000, the surface roughness was reduced by 77.98%. MAF effectively eliminates the surface defects and deteriorated layers on the inner wall of MP35N tubes, significantly improving the surface quality, which is of great significance for the subsequent preparation of high-quality vascular stents and their clinical applications. Full article

Background/Objectives: Facial analysis is critical for preoperative planning in facial plastic surgery, but traditional methods can be time consuming and subjective. This study investigated the potential of Artificial Intelligence (AI) for objective and efficient facial analysis in plastic surgery, with a specific focus on Multimodal Large Language Models (MLLMs). We evaluated their ability to analyze facial skin quality, volume, symmetry, and adherence to aesthetic standards such as neoclassical facial canons and the golden ratio. Methods: We evaluated four MLLMs—ChatGPT-4o, ChatGPT-4, Gemini 1.5 Pro, and Claude 3.5 Sonnet—using two evaluation forms and 15 diverse facial images generated by a Generative Adversarial Network (GAN). The general analysis form evaluated qualitative skin features (texture, type, thickness, wrinkling, photoaging, and overall symmetry). The facial ratios form assessed quantitative structural proportions, including division into equal fifths, adherence to the rule of thirds, and compatibility with the golden ratio. MLLM assessments were compared with evaluations from a plastic surgeon and manual measurements of facial ratios. Results: The MLLMs showed promise in analyzing qualitative features, but they struggled with precise quantitative measurements of facial ratios. Mean accuracy for general analysis were ChatGPT-4o (0.61 ± 0.49), Gemini 1.5 Pro (0.60 ± 0.49), ChatGPT-4 (0.57 ± 0.50), and Claude 3.5 Sonnet (0.52 ± 0.50). In facial ratio assessments, scores were lower, with Gemini 1.5 Pro achieving the highest mean accuracy (0.39 ± 0.49). Inter-rater reliability, based on Cohen’s Kappa values, ranged from poor to high for qualitative assessments (κ > 0.7 for some questions) but was generally poor (near or below zero) for quantitative assessments. Conclusions: Current general purpose MLLMs are not yet ready to replace manual clinical assessments but may assist in general facial feature analysis. These findings are based on testing models not specifically trained for facial analysis and serve to raise awareness among clinicians regarding the current capabilities and inherent limitations of readily available MLLMs in this specialized domain. This limitation may stem from challenges with spatial reasoning and fine-grained detail extraction, which are inherent limitations of current MLLMs. Future research should focus on enhancing the numerical accuracy and reliability of MLLMs for broader application in plastic surgery, potentially through improved training methods and integration with other AI technologies such as specialized computer vision algorithms for precise landmark detection and measurement. Full article

Background: Skin photoaging caused by ultraviolet B (UV-B) irradiation leads to the formation of wrinkles. A method to lessen wrinkles is the application of Polydioxanone (PDO) lifting threads. HanDam (Twist) is a PDO lifting thread with a unique morphological twisted shape. Objective: The aim of this study was to evaluate the wrinkle improvement ability of HanDam (Twist) on UV-B irradiation-induced skin photoaging in a hairless mouse model. Methods: Wrinkles were induced by UV-B irradiation to the backs of female hairless mice for six weeks. After induction, the wrinkles were treated with threads, and the mice were monitored for six weeks post-treatment. Results: Our results showed that treatment with HanDam (Twist) effectively ameliorated UV-B irradiation-induced wrinkle depth and significantly increased collagen density by 13% compared to HanDam (non-Twist) in the histological analysis. In measuring protein expression related to collagen production, HanDam (Twist) significantly increased transforming growth factor beta (TGF-β) and collagen type 1 (COL1) by 46% and 67% compared to HanDam (non-Twist). Matrix metalloproteinase-1 (MMP-1) protein expression showed similar density and no significance compared to HanDam (non-Twist). Conclusions: These findings suggest that HanDam (Twist) improves the effectiveness of lifting threads for skin care compared to that of existing products. Full article

To address the issues of manual inspection and low precision in the detection and recognition of defects in existing animal leather, this study first establishes a leather image dataset and applies an improved Gabor filtering algorithm for image preprocessing. Specifically, the weighted average method is adopted to grayscale the image, and the algorithm parameters are designed and improved to ensure that most of the key texture information of the leather images is obtained, meeting the requirements for texture feature information in subsequent feature extraction. Next, it explores statistical feature extraction algorithms based on the gray-level co-occurrence matrix and the statistical feature extraction algorithm based on gray-level distribution, forming a combination of features for the dataset. The leather defects mainly include warble fly holes, neck wrinkles, and scars. In the processing process, there are also defects such as scratches, holes, and stains. Finally, a leather defect image classification model is proposed based on a multilayer perceptron algorithm, using the ReLU activation function and a SoftMax classifier to classify surface defects in 1280 samples. The classification time is 0.0854 s, and the average precision, recall, and accuracy for leather defect image classification are all 99.53%. This solution innovatively integrates the improved Gabor filtering with the adaptive multilayer perceptron architecture to construct a multi-modal leather defect classification model, which significantly improves the detection accuracy of three types of defects, namely holes, scratches, and stains. It provides a theoretical reference for the automation of the leather processing process. Full article

Yarrow has long been known as a medicinal plant and has recently been gaining in importance as a cosmetic plant. The purpose of the study was to perform a phytochemical evaluation of extracts from yarrow herb of the Paprika cultivar, which has not previously been studied in this regard, and to determine its protective, antioxidant, and antimicrobial properties. Comparative analysis of two types of extracts, obtained by ultrasound-assisted extraction (UAE) and supercritical fluid extraction (SFE), showed that the former had higher content of bioactive compounds, including polyphenols, flavonoids, phenolic acids, and condensed tannins, as well as better antioxidant properties, as determined by spectrophotometric methods (DPPH and FRAP). The biological properties of the water–ethanol yarrow herb extract obtained by UAE was tested in vitro on 15 microbial strains (14 bacterial strains and one fungal strain), as well as on two lines of skin cells: HaCaT keratinocytes and HDF fibroblasts. In addition, the sun protection factor and rheological characteristics of a model cosmetic cream based on the extract were determined. Yarrow extract was shown to exhibit a number of important activities for cosmetic ingredients, including antimicrobial, antioxidant, photoprotective, and anti-ageing activity. The results of the study indicate that this material has potential applications in cosmetics, e.g., in products for mature skin with signs of ageing such as wrinkles or hyperpigmentation. Full article

Advanced glycation end-products (AGEs) cause blood vessel damage and induce diabetic complications in various organs, such as the eyes, kidneys, nerves, and skin. As glycation stress causes aesthetic, physical, and functional changes in the skin, glycation-targeting skin anti-aging strategies are attracting attention in cosmetology and dermatology. The primary goal of this review is to understand the significance of glycation-induced skin aging and to examine the therapeutic potential of glycation-targeting strategies. This study covers experimental and clinical studies exploring various interventions to attenuate glycation-induced skin aging. Glycation stress decreases the viability of cells in culture media, the cell-mediated contraction of collagen lattices in reconstructed skin models, and the expression of fibrillin-1 at the dermo-epidermal junction in the skin explants. It also increases cross-links in tail tendon collagen in animals, prolonging its breakdown time. However, these changes are attenuated by several synthetic and natural agents. Animal and clinical studies have shown that dietary or topical administration of agents with antiglycation or antioxidant activity can attenuate changes in AGE levels (measured by skin autofluorescence) and skin aging parameters (e.g., skin color, wrinkles, elasticity, hydration, dermal density) induced by chronological aging, diabetes, high-carbohydrate diets, ultraviolet radiation, or oxidative stress. Therefore, the accumulating experimental and clinical evidence supports that dietary supplements or topical formulations containing one or more synthetic and natural antiglycation agents may help mitigate skin aging induced by AGEs. Full article

The draping of textile semi-finished products for complex geometries is still prone to errors, e.g., wrinkles, gaps, and fiber undulations, leading to reduced mechanical properties of the composite. Reinforcing textiles made from carbon fiber (CF) rovings (i.e., endless continuous fibers) can be draped mainly based on their ability to deform under in-plane shearing. However, CF rovings are hardly stretchable in the fiber direction. These limited degrees of freedom make the production of complex shell-shaped geometries from standard CF-roving fabrics challenging. Contrary to continuous rovings, this paper investigates the processing of spun yarns made of recycled carbon fibers (rCFs), which are discontinuous staple fibers with defined lengths. rCFs are obtained from end-of-life composites or production waste, making them a sustainable alternative to virgin carbon fibers in the high-performance components of, e.g., automobiles, boats, or sporting goods. These staple fiber-spun yarns are considerably more stretchable, which is due to the ability of the individual fibers to slide against each other when deformed, resulting in improved formability of fabrics made from rCF yarns, enabling the draping of much more complex structures. This study aims to develop and characterize woven fabrics based on previous studies of rCF yarns for thermoset composites. In order to investigate staple fiber-spun yarns, a previous micro-scale modeling approach is extended. The formability of fabrics made from those rCF yarns is investigated through experimental forming tests and meso-scale simulations. Full article

The real-time detection of facial skin problems is crucial for improving dermatological health, yet its practical implementation remains challenging. Early detection and timely intervention can significantly enhance skin health while reducing the financial burden associated with traditional dermatological treatments. This paper introduces EM-YOLO, an advanced deep learning framework designed for embedded and distributed environments, leveraging improvements in YOLO models (versions 5, 7, and 8) for high-performance, real-time skin condition detection. The proposed architecture incorporates custom layers, including Squeeze-and-Excitation Block (SEB), Depthwise Separable Convolution (DWC), and Residual Dropout Block (RDB), to optimize feature extraction, enhance model robustness, and improve computational efficiency for deployment in resource-constrained settings. The proposed EM-YOLO model architecture clearly delineates the role of each architectural component, including preprocessing, detection, and postprocessing phases, ensuring a structured and modular representation of the detection pipeline. Extensive experiments demonstrate that EM-YOLO significantly outperforms traditional YOLO models in detecting facial skin conditions such as acne, dark circles, enlarged pores, and wrinkles. The proposed model achieves a precision of 82.30%, recall of 71.50%, F1-score of 76.40%, and mAP@0.5 of 68.80%, which are 23.52%, 32.7%, 29.34%, and 24.68% higher than standard YOLOv8, respectively. Furthermore, the enhanced YOLOv8 custom layers significantly improve system efficiency, achieving a request rate of 15 Req/s with an end-to-end latency of 0.315 s and an average processing latency of 0.021 s, demonstrating 51.61% faster inference and 200% improved throughput compared to traditional SCAS systems. These results highlight EM-YOLO’s superior precision, robustness, and efficiency, making it a highly effective solution for real-time dermatological detection tasks in embedded and distributed computing environments. Full article

In recent years there has been a resurgent interest in plant products as substitutes for animal-derived food products, in which legumes, including peas, feature highly. Here, we report on a set of Pisum sativum L. (pea) near-isolines, comprising 24 unique mutants at five loci, where the impact of the mutations on the corresponding enzymes of the starch pathway confers a wrinkled-seeded phenotype. Together with a set of round-seeded mutants impacted at a sixth locus, all 27 mutants show variation for starch composition and protein content. The mutations have been mapped onto three-dimensional protein models to examine potential effects on the corresponding enzyme structures and their activities, and to guide targeted mutagenesis. The mutant lines represent a unique suite of alleles for rapid introduction into elite pea varieties to create new materials for the food and feed markets and industrial applications. Full article

In regard to both natural aging and photoaging caused by UV radiation, a decrease in skin collagen and elastin fibers results in the loss of soft tissue volume. Biodegradable polymer fillers have been used to overcome this problem, but the slow rate of reconstruction and particle agglomeration has limited this approach. The DMSB01 filler, which consists of poly d-l-lactic acid (PDLLA) with a methoxy polyethylene glycol (mPEG) initiator, was created to address this issue. In this study, we assessed the reconstruction and dispersion of the DMSB01 filler in vitro, as well as its effect on collagen expression in rats. DMSB01 showed rapid reconstruction and excellent dispersion stability; gelation occurred within 5 min at 37 °C and remained stable. In an animal model, DMSB01 induced M2 macrophages, Transforming growth factor beta (TGF-β) expression, and significantly increased collagens I and III. Collagen recovery and wrinkle improvement were confirmed by the aging and photoaging models, and hematoxylin and eosin (H&E) staining was used to demonstrate the safety and biodegradability of DMSB01. DMSB01 was effective in terms of inducing collagen production and improving skin aging, and shows promise as an innovative ingredient to overcome the limitations of existing fillers. Full article