Wrinkle Formation Research Articles

Study of Parameters Influencing Wrinkles in the Deep Drawing of Fiber-Based Materials Using Automatic Image Detection

The evaluation of wrinkles in deep-drawn fiber-based materials is crucial for the assessment of product quality and the optimization of manufacturing processes. Wrinkling is a common phenomenon in the deep-drawing process and is caused by tangential compressive stresses on the flanges of the blank. This phenomenon is particularly prevalent for fiber-based materials with high tensile depths and can seriously affect the appearance and mechanical properties of the final product. The objective of this study is to identify the key process parameters affecting wrinkling and to deepen the understanding of their roles and interactions using wrinkle data for deep-drawn paper products. Image analysis techniques are employed, supported by a specially constructed darkroom platform to ensure uniform light intensity for capturing photographs. An automated program is developed for the detection and evaluation of wrinkle characteristics and distribution, which allows the free choice of the region to be detected and the representation of the wrinkle geometry not limited by the number. To enhance the precision of this program, the ellipticity is initially rectified for products without flanges, specifically cup-shaped deep-drawn products. The ellipticity is caused by the pronounced springback effect of the paperboard. The approach is employed to investigate the impact of material properties, blank holder force, drawing depth, drawing clearance, and punch speed on wrinkling formation after the deep-drawing process. The findings reveal that the blank holder force and drawing clearance are critical factors in wrinkle formation, with higher blank holder force generally leading to increased wrinkle numbers.

Computational Approach to Identifying New Chemical Entities as Elastase Inhibitors with Potential Antiaging Effects.

In the aging process, skin morphology might be affected by wrinkle formation due to the loss of elasticity and resilience of connective tissues linked to the cleavage of elastin by the enzymatic activity of elastase. Little information is available about the structural requirements to efficiently inhibit elastase 1 (EC 3.4.21.36) expressed in skin keratinocytes. In this study, a structure-based approach led to the identification to the pharmacophoric hypotheses that described the main structural requirements for binding to porcine pancreatic elastase as a valuable tool for the development of skin therapeutic agents due to its similarity with human elastase 1. The obtained models were subsequently refined through the application of computational alanine-scanning mutagenesis to evaluate the effect of single residues on the binding affinity and protein stability; in turn, molecular dynamic simulations were carried out; these procedures led to a simplified model bearing few essential features, enabling a reliable collection of chemical features for their interactions with elastase. Then, a virtual screening campaign on the in-house library of synthetic compounds led to the identification of a nonpeptide-based inhibitor (IC50 = 60.4 µM) belonging to the class of N-substituted-1H-benzimidazol-2-yl]thio]acetamides, which might be further exploited to obtain more efficient ligands of elastase for therapeutic applications.

Enhanced SIRT1 Activity by Galangin Mitigates UVB-Induced Senescence in Dermal Fibroblasts via p53 Acetylation Regulation and Activation.

Human skin aging, a complex process influenced by intrinsic aging and extrinsic photoaging, is marked by the accumulation of reactive oxygen species (ROS) that cause DNA damage, impaired dermal fibroblast function, and wrinkle formation. External stressors, such as ultraviolet (UV) radiation, can trigger cellular senescence. Sirtuin-1 (SIRT1), an NAD+-dependent enzyme in the sirtuin family, plays a crucial role in deacetylating p53, thereby inhibiting its nuclear translocation and reducing skin senescence. Galangin, a flavonoid found in honey and Alpinia officinarum root, has antioxidant and anti-inflammatory properties. This study investigates the protective mechanism of galangin against UVB-induced senescence in human dermal fibroblasts (HDFs) by examining its effects on SIRT1 and its target, acetylated-p53. An in vitro model of UVB-induced senescence using HDFs and an in vivo model using nude mice were employed to assess the dermal protective effects of galangin. The results demonstrate that while UVB exposure does not decrease SIRT1 protein levels, it impairs its enzymatic function. However, galangin treatment counteracts these adverse effects. Additionally, UVB exposure significantly reduces cell viability and upregulates senescence markers like p16, p21, and p53 nuclear transactivation. An increase in senescence-associated β-galactosidase (SA-β-gal) positive cells was observed in UVB-exposed dermal fibroblasts. Galangin treatment mitigates UVB-induced cellular senescence by enhancing SIRT1-mediated p53 deacetylation, thereby inhibiting nuclear translocation and reducing dermal senescence. These findings suggest that galangin is a promising agent for alleviating UVB-induced skin aging and could be a potential component in antiaging cosmetic formulations.

Comprehensive analysis of Hibisci mutabilis Folium extract's mechanisms in alleviating UV-induced skin photoaging through enhanced network pharmacology and experimental validation.

Skin photoaging induced by ultraviolet A (UVA) and ultraviolet B (UVB) radiation manifests as skin roughness, desquamation, pigmentation, and wrinkle formation. Current treatments, such as sunscreen, hormones, and antioxidants, have limitations and side effects. Traditional Chinese Medicine Hibisci Mutabilis Folium (HMF), or Mu-Fu-Rong-Ye in Chinese name, refers to the dried leaves of the plant Hibiscus mutabilis L., which belongs to the Malvaceae family. It has been used traditionally to treat acute mastitis, parotitis, neurodermatitis, burns. The reported activities of HMF include anti-inflammatory and anti-oxidant effects. However, the therapeutic potential of HMF in preventing and treating UV-induced skin photoaging remains unexplored. This study aimed to investigate the protective effects of HMF extract (EHMF) against UV-induced skin photoaging and the underlying mechanisms of action, by using network pharmacology and experimental verification. Network pharmacology was employed to identify the effective chemical components of EHMF. Potential targets were identified via PPI network analysis. Representative compounds were characterized using UPLC-MS/MS. In vitro validation involved assessing HaCaT cell viability, observing live/dead cell staining through fluorescence microscopy, and measuring inflammatory factors using ELISA. For in vivo validation, a UV-induced skin photoaging mice model was treated transdermally with EHMF or Methotrexate daily for 7 days. Dermatitis severity, skin morphology, and collagen fiber pathology were evaluated. Inflammatory cytokine and protein expression in dorsal skin lesions was confirmed using Elisa Kits, Western blot and immunohistochemistry. A total of 22 active ingredients of EHMF were identified. GO enrichment and KEGG pathway analyses revealed a focus on inflammatory signaling pathways. In vitro experiments showed that EHMF significantly reduced UV-induced inflammatory factors in HaCaT cells and improved cell survival rates. In vivo, EHMF alleviated back skin lesions in UV-exposed mice, reducing epidermal and dermal thickening and pathological inflammatory cell infiltration. It also decreased abnormal MMP-9 expression and collagen fiber proliferation, along with levels of inflammatory factors like TNF-α, IL-6, IL-17, and EGFR. Western blot and immunohistochemistry results indicated that the over-activation of the AKT-STAT3 signaling pathway was inhibited. EHMF effectively reduced UV-induced skin damage, inflammation, and wrinkles, providing strong support for its clinical application as a dermatological agent.

Elephants develop wrinkles through both form and function.

The trunks of elephants have prominent wrinkles from their base to the very tip. But neither the obvious differences in wrinkles between elephant species nor their development have been studied before. In this work, we characterize the lifelong development of trunk wrinkles in Asian and African elephants. Asian elephants have more dorsal major, meaning deep and wide, trunk wrinkles (approx. 126 ± 25 s.d.) than African elephants (approx. 83 ± 13 s.d.). Both species have more dorsal than ventral major trunk wrinkles and a closer wrinkle spacing distally than proximally. In Asian elephants, wrinkle density is high in the 'trunk wrapping zone'. Wrinkle numbers on the left and right sides of the distal trunk differed as a function of trunk lateralization, with frequent bending in one direction causing wrinkle formation. Micro-computed tomography (microCT) imaging and microscopy of newborn elephants' trunks revealed a constant thickness of the putative epidermis, whereas the putative dermis shrinks in the wrinkle troughs. During fetal development, wrinkle numbers double every 20 days in an early exponential phase. Later wrinkles are added slowly, but at a faster rate in Asian than African elephants. We discuss the relationship of species differences in trunk wrinkle distribution and number with behavioural, environmental and biomechanical factors.

Oyster hydrolysate ameliorates UVB-induced skin dehydration and barrier dysfunction

Ultraviolet (UV) exposure triggers skin aging primarily by disrupting skin barrier function, resulting in dry skin and wrinkle formation. Oyster hydrolysate (OH), as a functional food, has been reported for anti-cancer, anti-oxidant and anti-apoptotic effects. This study investigated the underlying mechanism of OH effect on UVB-induced skin aging in SKH1 hairless mice.Mice were exposed to UVB three times per week while they were fed with a normal diet or diet containing OH for 10 weeks. Additionally, a randomized, double-blind, and placebo-controlled clinical trial was performed to investigate the OH effect on human skin moisturizing to evaluate its efficacy and safety.UVB exposure increased parameters of skin aging; dehydration, transepidermal water loss, and macroscopic dorsal skin lesions. OH significantly reduced these features of skin aging. Histological analysis demonstrated that OH decreased skin epidermal and dermal thickness and collagen degradation induced by UVB. OH significantly reduced ROS production, suppressed macrophage activation and neutrophil infiltration, and downregulated pro-inflammatory cytokine production. OH improved skin barrier function by increasing the expression of filaggrin, aquaporin-3, and hyaluronic acid synthesis enzymes and promoting recovery from skin damage. Importantly, the results from a human clinical trial demonstrated that OH improved skin moisturization and integrity with no side effects.Taken together, OH supplementation ameliorates skin damage via anti-oxidant and anti-inflammatory properties and enhances skin hydration and barrier function. OH has a therapeutic potential to skin photoaging.

Protective Effects of Sesame Glycoproteins on Ultraviolet-Induced Skin Aging: In Vitro and In Vivo Studies.

Ultraviolet (UV) radiation is a primary factor in skin photoaging, leading to wrinkles, reduced elasticity, and pigmentation changes due to damage to cellular DNA, proteins, and lipids. Glycoproteins from sesame cake (SPE) have potential protective effects against UV-induced skin aging. This study investigated the anti-photoaging effects of SPE on UV-induced damage in human keratinocyte HaCaT cells and SKH-1 hairless mice. SPE was evaluated for its ability to mitigate UV-induced damage in HaCaT cells by assessing MMP-1 protein and mRNA expression levels, as well as the activity of transcription factors AP-1 and NF-κB. The phosphorylation of AKT and MAPK pathways was also analyzed. In vivo, SKH-1 hairless mice were exposed to UV radiation, and the effects of SPE on wrinkle formation and skin structure were assessed by measuring wrinkle length, area, and volume. SPE significantly inhibited UV-induced MMP-1 protein and mRNA expression in HaCaT cells, indicating suppression of AP-1 and NF-κB transcription factors involved in MMP-1 production. Additionally, SPE reduced UV-induced phosphorylation of AKT and MAPK pathways. In SKH-1 hairless mice, SPE treatment led to significant reductions in wrinkle length, area, and volume, preserving skin structure in UV-exposed mice. The findings demonstrate that SPE has protective effects against UV-induced photoaging by inhibiting key molecular pathways associated with skin aging. SPE shows promise as a natural anti-photoaging agent, providing a foundation for future skincare product development. Further studies are warranted to explore the molecular mechanisms in detail and to validate these effects through clinical trials.

Parallel Concentric Wrinkled Polydimethylsiloxane Patterns and Their Potential Biomedical Applications

AbstractThe objective of this study is to examine microbial behavior by fabricating and applying parallel concentric wrinkled patterns to polydimethylsiloxane (PDMS) substrates. The patterns are generated and subsequently relaxed in a rigid silica layer, resulting in the formation of discernible wrinkles that can be analyzed using electron microscopy and light diffraction. The alignment of E. coli and silica microparticles is facilitated by these structures along the creases. Within these creases, E. coli exhibits enhanced attachment and rotational mobility in regions characterized by hydrophobic cracks. Furthermore, the bacteria demonstrate an increase in velocity when propelled by the PDMS creases, suggesting that these structures are capable of guiding microbial motion. In addition, distinct alignment and growth patterns are observed for E. coli proliferation within the PDMS microchannels under confined conditions. The analysis of bacterial morphology and gene expression in response to chemical stimuli, such as isopropyl‐β‐D‐thiogalactopyranoside (IPTG) gradients, demonstrates that the chemical environment has a substantial impact; filamentous cells aligned along the creases. These results illustrate the efficacy of parallel concentric wrinkled PDMS patterns in establishing regulated conditions for investigating microbial behavior and represent significant contributions to the fields of microbiology and biomedicine.

Host Material Viscoelasticity Determines Wrinkling of Fungal Films.

Microbial organisms react to their environment and are able to change it through biological and physical processes. For example, fungi exhibit various growth morphologies depending on their host material. Here, we show how the rheological properties of the host material influence the fungal wrinkling morphology. Rheological data of the host material was set in relation to the growth morphology. On host material with high storage modulus, the fungal film was flat, whereas on host material with low storage modulus, the fungus showed a morphology made of folds and wrinkles. We combined our findings with mechanical instability theories and found that the formation of wrinkles and folds is dependent on the storage modulus of the host material. The connection between the wrinkling morphology and the storage modulus of the host material is shown with simple scaling theories. The amplitude, number of wrinkles, and wrinkle length follow geometrical laws, and the mechanical properties of the fungal film are expected to increase with increasing host material elasticity. The obtained results show the connection between living biological films, how they react to their surroundings, and the underlying physical mechanisms. They can provide a framework to further design fungal materials with specific surface morphologies.

Ultra-small platinum nano-enzymatic spray with ROS scavenging and anti-inflammatory properties for photoaging treatment

Photoaging induced by ultraviolet (UV) results in oxidative stress and inflammation. Noble metal nanozymes have strong antioxidant and anti-inflammatory capacity, which are expected to eliminate the excessive reactive oxygen species (ROS) and inflammatory factors in the photoaged skin. Hence, we have synthesized ultrasmall platinum nanoparticles coated with polyvinylpyrrolidone (Pt NPs) with a diameter of nearly 5 nm for photoaging treatment. Thanks to multi-enzymatic capacities (catalase, peroxidase, and superoxide dismutase) of Pt NPs, they can effectively protect fibroblasts from UV-induced ROS attack, relieve fibroblasts from UV-induced cell cycle arrest, downregulate matrix metalloproteinases (MMPs) to regenerate type I collagen, and inhibit M1 macrophage polarization to decrease the expression of inflammatory factors. For photoaged mice treatment, we employ the concept of routine spray skincare and encapsulate Pt NPs solution in a spray bottle. In combination with roller needle, following Pt NPs nano-enzymatic spray given, UV-induced photoaged mice display reduced wrinkle formation in the collagen-depleted dermal tissue of mice and more youthful performance in both appearance and organizational structure. Consequently, multi-enzymatic functions of Pt NPs nano-spray offers a promising avenue for anti-photoaging therapy, providing potential benefits in both preventative and restorative skincare applications.

The effect of degeneration of elastic fibres on loss of elasticity and wrinkle formation.

Skin elasticity, which is vital for a youthful appearance, depends on the elastic fibres in the dermis. However, these fibres deteriorate with ageing, resulting in wrinkles and sagging. Changes that occur in the elastic fibres in living human skin and the relationship between elastic fibres and the state of the skin surface remain unclear. Therefore, it is necessary to verify the relationship between elastic fibres and skin elasticity. In this study, we investigated the association of the elastic fibre structure with skin elasticity and stratum corneum protein content in living human skin. Thirty-five female volunteers aged 25-66 years were included in this study. Elastic fibres were observed using a multiphoton scanning laser biomicroscope. Skin elasticity was measured using a Cutometer, and stratum corneum proteins (Heat-shock protein 27 [HSP27] and galectin-7 [Gal-7]) in tape-stripped samples were analysed using an enzyme-linked immunosorbent assay. Elastic fibres exhibited increased curvature and thickness with increased age, with fragmentation observed in women aged >60 years. Elastin scores, which reflect thinness and curvature, were negatively correlated with age, whereas they were positively correlated with R7 elasticity (recovery ability). In individuals aged 20-30 years, higher levels of inflammatory markers (HSP27 and Gal-7) correlated with lower elastin scores; however, this trend was not observed in older participants. Elastic fibre deterioration worsened after 40 years of age, and this effect correlated with reduced skin recovery and increased wrinkles. In younger individuals, inflammatory markers affected elastic fibres. These findings can guide anti-ageing strategies that focus on elastic fibre preservation and inflammation control.

Chikusetsusaponin IVa from Dolichos lablab Linne attenuates UVB-induced skin photoaging in mice by suppressing MAPK/AP-1 signaling

Ultraviolet-B (UVB) radiation-induced photoaging of the skin is characterized by amplified expression of matrix metalloproteinase-1 (MMP-1) and reduced collagen fibers, both of which contribute to skin wrinkle formation. Edible natural products can protect against skin photoaging. Here, we investigate the protective effect of Dolichos lablab Linne (DLL) water extract against UVB radiation-prompted skin damage and attempt to uncover its fundamental mechanisms in human keratinocytes (HaCaT) and HR-1 hairless mouse. We found DLL extract rescued the reduction in cell viability associated with UVB exposure without any associated cytotoxic effects. It also protected against skin photoaging by inhibiting mitogen-activating protein kinase (MAPK) signaling, thereby preventing the UVB-associated increase in MMP-1 and -9 expression. DLL extract also increased the expression of both superoxide dismutase 1 (SOD1) and catalase (CAT). We identified chikusetsusaponin IVa, soyasaponin Bb, and sandosaponin A as bioactive components of DLL. Although we have not yet identified the mechanisms by which these compounds reduce the effects of photoaging, we have demonstrated that chikusetsusaponin IVa, soyasaponin Bb, and sandosaponin A reduce MMP-1, MMP-9, p–c-Fos, and p–c-Jun expression, while also avoiding any cytotoxicity. We found oral administration of DLL extract effectively alleviated dorsal epidermal thickening and skin dehydration in HR-1 hairless mouse visible to UVB. DLL extract also prevents UVB-induced activation of the MAPK/AP-1 signaling pathway, thereby reducing the expression of MMPs in dorsal mouse skin. Our results indicate that chikusetsusaponin IVa, soyasaponin Bb, and sandosaponin A are bioavailable components of DLL extract that can reduce UVB-induced skin damage via MMPs by deactivating the MAPK/AP-1 signaling pathway. These findings suggest DLL extract can be used as a skin anti-photoaging agent.

Actinidia chinensis Planch Ameliorates Photoaging in UVB-Irradiated NIH-3T3 Cells and SKH-1 Hairless Mice by Controlling the Reactive Oxygen Species/AKT Pathway.

In this study, we evaluated the antiphotoaging properties of Actinidia chinensis Planch (ACP) and the molecular mechanisms underlying its ability to prevent UVB-mediated photoaging. Administration of the ethanolic extract of ACP (EEACP) to the dorsal area of hairless mice effectively ameliorated UVB-mediated wrinkle formation, epidermal thickening, and loss of lipid droplets in the epidermis. Additionally, the UVB-induced loss of collagen content in the epidermis was significantly attenuated in mouse skin treated with EEACP. The expression of procollagen type 1 and metalloproteinase-1a, which are related to collagen content in the epidermis, was restored by EEACP treatment in UVB-irradiated mice and NIH-3T3 mouse skin fibroblast cells. Interestingly, EEACP effectively ameliorated UVB-induced reactive oxygen species overproduction. Furthermore, the activation/phosphorylation of AKT, rather than mitogen-activated protein kinases, has been identified as a major target of EEACP in preventing UVB-mediated photoaging. Additionally, N-(1 deoxy-1-fructosyl) valine and phenethylamine glucuronide were identified as analytical indicators of EEACP using high-performance liquid chromatography/mass spectrometry. These results suggest that EEACP can be developed as a functional natural agent capable of preventing photoaging by attenuating UVB-induced activation of the reactive oxygen species/AKT pathway.

Downregulation of carnitine acetyltransferase by promoter hypermethylation regulates ultraviolet-induced matrix metalloproteinase-1 expression in human dermal fibroblasts

BackgroundOverexposure to ultraviolet (UV) radiation accelerates skin aging, resulting in wrinkle formation, reduced skin elasticity, and hyperpigmentation. UV irradiation induces increased matrix metalloproteinases (MMPs) that degrade collagen in the extracellular matrix. Skin aging is also accompanied by epigenetic alterations such as promoter methylation by DNA methyltransferases, leading to the activation or suppression of gene expression. Although carnitine acetyltransferase (CRAT) is implicated in aging, the effect of UV on the expression of CRAT and regulatory mechanisms of UV-induced MMP-1 expression remain unknown. ObjectiveWe investigated changes in CRAT expression upon UV irradiation and its effect on MMP-1 expression. MethodsPrimary human dermal fibroblasts were UV irradiated with either control or 5-AZA-dC. CRAT knockdown or overexpression was performed to investigate its effect on MMP-1 expression. The mRNA level was analyzed by quantitative real-time PCR, and protein level by western blotting. ResultsThe expression of CRAT was decreased in UV-irradiated human skin in vivo and in human dermal fibroblasts in vitro. CRAT was downregulated upon UV irradiation by hypermethylation, and treatment with 5-Aza-2′-deoxycytidine, a DNA methyltransferase inhibitor, reversed UV-induced downregulation of CRAT. CRAT knockdown activated the JNK, ERK, and p38 MAPK signaling pathways, which increased MMP-1 expression. Stable overexpression of CRAT alleviated UV-induced MMP-1 induction. ConclusionCRAT downregulation caused by promoter hypermethylation may play an important role in UV-induced skin aging via upregulation of MMP-1 expression.

Promoting grain refinement and nanocrystal generation in surface nanomachining by means of overlapping collisions

Surface nanostructuring effectively improves the mechanical properties and wear resistance of the moving parts, yet a thorough understanding of its formation mechanism remains elusive. This study examined the microstructure evolution of pure copper under various linear overlapping ratios (φ) using a self-made impact wear tester. The results revealed that high Smid factor grains activate the basal slip system to handle deformation during repeated impacts. Still, overlapping impacts can intensify plastic deformation by activating multiple slip systems and boosting dislocation proliferation. Moreover, overlapping collisions will generate Frank's incomplete dislocations, hindering dislocation slip and generating cross slip trajectories, resulting in the bending of slip-trajectories, the formation of uneven wrinkles, and the refinement of superficial grains.

Preventive effects of dietary fucoxanthin on ultraviolet A induced photoaging in hairless mice.

Repeated exposure to ultraviolet A (UVA) irradiation, which can penetrate the epidermis and reach the dermis, is one of the major causes of skin photoaging. Photoaged skin is characterized clinically by generalized wrinkling, a dry and loose appearance, and seborrheic keratoses, along with skin barrier dysfunction. Fucoxanthin, a xanthophyll carotenoid with a specific allenic bond and 5,6-monoepoxide in its structure, has been found to serve various functions as a food supplement. In the present study, the protective effects of orally administered fucoxanthin at relatively low concentrations (0.001% and 0.01%) against UVA induced photoaging were evaluated in vivo using hairless mice. Oral supplementation of 0.001% fucoxanthin was sufficient for its metabolites to accumulate in the skin, thereby inhibiting pathological changes induced by UVA irradiation, including impaired skin barrier function and accelerated wrinkle formation. Analysis of gene expression revealed that dietary fucoxanthin exerted antiphotoaging effects, possibly by modulating natural moisturizing factor (NMF) synthesis, desquamation, and ceramide composition in the epidermis, and by inhibiting the UVA induced degradation of collagen fibers and inflammation in the dermis. Taken together, our data indicate the potential application of dietary fucoxanthin as a novel ingredient in nutricosmetics for skin care against photoaging. © 2024 Society of Chemical Industry.

Phase-Change Stamp with Highly Switchable Adhesion and Stiffness for Damage-Free Multiscale Transfer Printing.

Transfer printing is a technology widely used in the production of flexible electronics and vertically stacked devices, which involves the transfer of predefined electronic components from a rigid donor substrate to a receiver substrate with a stamp, potentially avoiding the limitations associated with lithographic processes. However, the stamps typically used in transfer printing have several limitations related to unwanted organic solvents, substantial loading, film damage, and inadequate adhesion switching ratios. This study introduces a thermally responsive phase-change stamp for efficient and damage-free transfer printing inspired by the adhesion properties observed during water freezing and ice melting. The stamp employs phase-change composites and simple fabrication protocols, providing robust initial adhesion strength and switchability. The underlying mechanism of switchable adhesion is investigated through experimental and numerical studies. Notably, the stamp eliminates the need for extra preload by spontaneously interlocking with the ink through in situ melting and crystallization. This minimizes ink damage and wrinkle formation during pickup while maintaining strong initial adhesion. During printing, the stamp exhibits a sufficiently weak adhesion state for reliable and consistent release, enabling multiscale, conformal, and damage-free transfer printing, ranging from nano- to wafer-scale. The fabrication of nanoscale short-channel transistors, epidermal electrodes, and human-machine interfaces highlights the potential of this technique in various emerging applications of nanoelectronics, nano optoelectronics, and soft bioelectronics.

Characterization and Modeling of Out-of-Plane Behavior of Fiber-Based Materials: Numerical Illustration of Wrinkle in Deep Drawing.

The characterization and modeling of the out-of-plane behavior of fiber-based materials is essential for understanding their mechanical properties and improving their performance in various applications, especially in the forming process. Despite this, research on paper and paperboard has mainly focused on its in-plane behavior rather than its out-of-plane behavior. However, for accurate material characterization and modeling, it is critical to consider the out-of-plane behavior. In particular, delamination occurs during forming processes such as creasing, folding, and deep drawing. In this study, three material models for paperboard are presented: a single all-material continuum model and two composite models using different cohesion methods. The two composite models decouple in-plane and out-of-plane behavior and consist of continuum models describing the behavior of individual layers and cohesive interface models connecting the layers. Material characterization experiments are performed to derive the model parameters and verify the models. The models are validated using three-point bending and bulge tests and show good agreement. A case study is also conducted on the application of the three models in the simulation of a deep drawing process with respect to wrinkle formation. By comparing the simulation results of wrinkle formation in the deep drawing process, the composite models, especially the cohesive interface composite model, show greater accuracy in replicating the experimental results, indicating that a single continuum model can also be used to represent wrinkles.

Efficacy of SGPP2 Modulation-Mediated Materials in Ameliorating Facial Wrinkles and Pore Sagging.

Skin aging is a complex process with internal and external factors. Recent studies have suggested that enlargement and elongation of skin pores may be early signs of aging in addition to wrinkles and loss of elasticity. This study explores the potential of targeting the SGPP2 gene in keratinocytes to address these emerging concerns. Using siRNA knockdown, we demonstrated that SGPP2 modulates the production of inflammatory cytokines (interleukin (IL)-1β and IL-8). Furthermore, conditioned media experiments revealed that keratinocytes with high SGPP2 expression indirectly influence fibroblast extracellular matrix remodeling, potentially contributing to enlarged pores and wrinkle formation. Based on these findings, we explored a complex formulation containing four SGPP2-modulating compounds. In vitro and in vivo experiments demonstrated the efficacy of the formulation in mitigating fine wrinkles and pore enlargement. This study highlights the significant implications of developing a more effective antiaging cosmetic formulation by targeting underlying inflammatory processes that drive skin aging.

Ultraflat single-crystal hexagonal boron nitride for wafer-scale integration of a 2D-compatible high-κ metal gate.

Hexagonal boron nitride (hBN) has emerged as a promising protection layer for dielectric integration in the next-generation large-scale integrated electronics. Although numerous efforts have been devoted to growing single-crystal hBN film, wafer-scale ultraflat hBN has still not been achieved. Here, we report the epitaxial growth of 4 in. ultraflat single-crystal hBN on Cu0.8Ni0.2(111)/sapphire wafers. The strong coupling between hBN and Cu0.8Ni0.2(111) suppresses the formation of wrinkles and ensures the seamless stitching of parallelly aligned hBN domains, resulting in an ultraflat single-crystal hBN film on a wafer scale. Using the ultraflat hBN as a protective layer, we integrate the wafer-scale ultrathin high-κ dielectrics onto two-dimensional (2D) materials with a damage-free interface. The obtained hBN/HfO2 composite dielectric exhibits an ultralow current leakage (2.36 × 10-6 A cm-2) and an ultrathin equivalent oxide thickness of 0.52 nm, which meets the targets of the International Roadmap for Devices and Systems. Our findings pave the way to the synthesis of ultraflat 2D materials and integration of future 2D electronics.