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Ubiquitin C‐terminal hydrolase L1 (UCHL1) plays vital roles in cell proliferation, angiogenesis, inflammation and oxidative stress. Nevertheless, it is unclear whether UCHL1 could regulate the biologic behaviour of cells and ultimately influences wound healing. We aim to illustrate the roles and the underlying mechanism of UCHL1 in cutaneous wound healing. Murine full‐thickness excisional wound model was utilised to study the effects of UCHL1 on wound healing through topical administration of the UCHL1 inhibitor LDN57444, followed by assessment of wound areas and histological alterations. Subsequently, ethynyldeoxyuridine, scratch and transwell assays were performed to examine fibroblast migration and proliferation. The extracellular matrix (ECM)‐related genes expression and transforming growth factor‐β (TGF‐β)/Smad signalling pathways activation were investigated by immuno‐fluorescent staining, Western blots and quantitative reverse transcription polymerase chain reaction. We identified elevated UCHL1 expression in non‐healing wound tissues. The UCHL1 expression displayed a dynamic change and reached a peak on Day‐7 post‐wounding during the healing process in mice. Cutaneous administration of LDN57444 promoted wound healing by facilitating collagen deposition, myofibroblast activation and angiogenesis. In vitro experiments demonstrated that UCHL1 concentration dependently inhibited migration, ECM synthesis and activation of human dermal fibroblasts, which was mechanistically related to downregulation of TGF‐β/Smad signalling. Furthermore, these effects could be reversed by TGF‐β inhibitor SB431542. Our findings reveal that UCHL1 is a negative regulator of cutaneous wound healing and considered as a novel prospective therapeutic target for effective wound healing. [ABSTRACT FROM AUTHOR]

X80 steel plays a pivotal role in the development of oil and gas pipelines; however, its welded joints, particularly the heat-affected zone (HAZ), are susceptible to stress corrosion cracking (SCC) due to their complex microstructures. This study investigates the SCC initiation mechanisms of X80 steel welded joints under practical pipeline conditions with varying levels of cathodic protection. The SCC behaviors were analyzed through electrochemical measurements, hydrogen permeation tests, and interrupted slow strain rate tensile tests (SSRTs) conducted in a near-neutral pH environment under different potential conditions (OCP, −1.1 VSCE, −1.2 VSCE). These behaviors were influenced by microstructure type, grain size, martensite/austenite (M/A) constituents, and dislocation density. The sub-zones of the weld exhibited differing SCC resistance, with the fine-grain (FG) HAZ, base metal (zone), welded metal (WM) zone, and coarse-grain (CG) HAZ in descending order. In particular, the presence of coarse grains, low dislocation density, and extensive M/A islands collectively increased corrosion susceptibility and SCC sensitivity in the CGHAZ compared to other sub-zones. The SCC initiation mechanisms of the sub-zones within the X80-steel welded joint were primarily anodic dissolution (AD) under open-circuit potential (OCP) condition, shifting to either hydrogen-enhanced local plasticity (HELP) or hydrogen embrittlement (HE) mechanisms at −1.1 VSCE or −1.2 VSCE, respectively. [ABSTRACT FROM AUTHOR]

Medium-carbon, high-strength steels are widely used in the field of hydrogen energy because of their good mechanical properties, and they can be readily tailored by heat treatment processes such as the normalizing–tempering (N&T) and quenching–tempering (Q&T) methods. The hydrogen embrittlement (HE) susceptibility of a medium-carbon, high-strength steel was investigated utilizing microstructural characterization with scanning electron microscopy (SEM), the electron backscatter diffraction (EBSD) technique, and transmission electron microscopy (TEM). A study was also conducted on the steel's hydrogen transport behavior as affected by the N&T and Q&T treatments. The steel contained more hydrogen traps, such as dislocations, grain boundaries, lath boundaries, and carbide interfaces, after the Q&T process, which was associated with a lower HE sensitivity when comparing the two treatments. In comparison, the N&T process produced larger-size and lesser-density carbides distributed along the grain boundaries, and this resulted in a relatively higher HE susceptibility, as revealed by the slow-strain-rate tensile (SSRT) tests of the hydrogen-charged steels and by the fractographic study of the fracture surface. [ABSTRACT FROM AUTHOR]

In response to the rapid development of high-performance electronic devices, diamond/Al composites with high thermal conductivity (TC) have been considered as the latest generation of thermal management materials. This study involved the fabrication of diamond/Al composites reinforced with Ti-coated diamond particles using a liquid–solid separation (LSS) method. The interfacial characteristics of composites both without and with Ti coatings were evaluated using SEM, XRD, and EMPA. The results show that the LSS technology can fabricate diamond/Al composites without Al4C3, hence guaranteeing excellent mechanical and thermophysical properties. The higher TC of the diamond/Al composite with a Ti coating was attributed to the favorable metallurgical bonding interface compounds. Due to the non-wettability between diamond and Al, the TC of uncoated diamond particle-reinforced composites was only 149 W/m·K. The TC of Ti-coated composites increased by 85.9% to 277 W/m·K. A simultaneous comparison and analysis were performed on the features of composites reinforced by Ti and Cr coatings. The results suggest that the application of the Ti coating increases the bending strength of the composite, while the Cr coating enhances the TC of the composite. We calculate the theoretical TC of the diamond/Al composite by using the differential effective medium (DEM) and Maxwell prediction model and analyze the effect of Ti coating on the TC of the composite. [ABSTRACT FROM AUTHOR]

Due to corrosion characteristics, there are data scarcity and uneven distribution in corrosion datasets, and collecting high-quality data is time-consuming and sometimes difficult. Therefore, this work introduces a novel data augmentation strategy using a conditional tabular generative adversarial network (CTGAN) for enhancing corrosion datasets of pipelines. Firstly, the corrosion dataset is subjected to data cleaning and variable correlation analysis. The CTGAN is then used to generate external environmental factors as input variables for corrosion growth prediction, and a hybrid model based on machine learning is employed to generate corrosion depth as an output variable. The fake data are merged with the original data to form the synthetic dataset. Finally, the proposed data augmentation strategy is verified by analyzing the synthetic dataset using different visualization methods and evaluation indicators. The results show that the synthetic and original datasets have similar distributions, and the data augmentation strategy can learn the distribution of real corrosion data and sample fake data that are highly similar to the real data. Predictive models trained on the synthetic dataset perform better than predictive models trained using only the original dataset. In comparative tests, the proposed strategy outperformed other data generation methods. [ABSTRACT FROM AUTHOR]

Podocytes are key to the glomerular filtration barrier by forming a slit diaphragm between interdigitating foot processes; however, the molecular details and functional importance of protein folding and degradation in the ER remain unknown. Here, we show that the SEL1L-HRD1 protein complex of ER-associated degradation (ERAD) is required for slit diaphragm formation and glomerular filtration function. SEL1L-HRD1 ERAD is highly expressed in podocytes of both mouse and human kidneys. Mice with podocyte-specific Sel1L deficiency develop podocytopathy and severe congenital nephrotic syndrome with an impaired slit diaphragm shortly after weaning and die prematurely, with a median lifespan of approximately 3 months. We show mechanistically that nephrin, a type 1 membrane protein causally linked to congenital nephrotic syndrome, is an endogenous ERAD substrate. ERAD deficiency attenuated the maturation of nascent nephrin, leading to its retention in the ER. We also show that various autosomal-recessive nephrin disease mutants were highly unstable and broken down by SEL1L-HRD1 ERAD, which attenuated the pathogenicity of the mutants toward the WT allele. This study uncovers a critical role of SEL1L-HRD1 ERAD in glomerular filtration barrier function and provides insights into the pathogenesis associated with autosomal-recessive disease mutants., Introduction The key function of the kidneys is the ultrafiltration of blood in the glomerulus, where podocytes, specialized differentiated epithelial cells, wrap around capillaries of the glomerulus via a unique [...]

Supercapacitors (SCs) based on carbon nanofibers (CNFS) are being paid much attention due to their fast charge–discharge rate, high power density, and excellent cyclic stability. Herein, a kind of preferred hydroxyl‐containing poly(amic acid) solution is first synthesized by using 2,2‐bis(3‐amino‐4‐hydroxyphenyl)hexafluoropropane and pyromellitic dianhydride as monomers, and electrospun to prepare nanofiber membranes. Then, thermal imidization, thermally rearranged treatment, and carbonization are employed to successfully fabricate the corresponding hydroxyl‐containing polyimide (HPI)‐CNFs. Next, the activated CNFS are obtained through a simple activation treatment with KOH. After optimizing the concentration of KOH solution, the self‐standing and binder‐free CNF electrode A–HPI–CNFs–1/3 exhibits a maximum specific surface area of 2058 m2 g−1 and pore volume of 1.04 cm3 g−1, leading to a high specific capacitance of 387.7 F g−1 at 0.5 A g−1 and rate capability of 70% at 10 A g−1. In addition, the assembled symmetrical SC device shows outstanding cycle stability performance after 50000 runs of charge–discharge with a specific capacitance retention of 99.93% at 1 A g−1. Finally, the SC demonstrates a specific power of 12.7 Wh kg−1 at a specific energy of 250.0 W kg−1, suggesting potential application prospects in the field of SCs. [ABSTRACT FROM AUTHOR]

Externally physical fields such as stress field, electric field and magnetic field have been demonstrated influence the equilibria and kinetics of solid-state transformations in metals and alloys. This review focuses on the effects of externally physical fields on the aging precipitation of aerospace Al alloys including 2xxx Al-Cu alloys, 7xxx Al-Zn-Mg alloys as well as the advanced Al-Li alloys. While the η' phase in Al-Zn-Mg alloy and the T1 phase in Al-Li alloy showed no obvious stress-orientating effect, the precipitation of θ' phase in Al-Cu alloy showed obvious stress-orientating effect depending on the applied stress direction. Regarding precipitation kinetics, aging under stress field, electric field and magnetic field all can enhance the aging precipitation of aerospace Al alloys. The understanding of the effects of externally physical field on the aging precipitation in Al alloys is very preliminary. It appears that while the stress field acts on the thermally activated transformation, the athermal effect associating with electromigration of electromagnetic field has been considered responsible for the enhanced aging precipitat ion. [ABSTRACT FROM AUTHOR]

Summary: Fusarium head blight (FHB), caused by Fusarium graminearum, is a devastating disease in wheat (Triticum aestivum) that results in substantial yield losses and mycotoxin contamination. Reliable genetic resources for FHB resistance in wheat are lacking. In this study, we characterized glycoside hydrolase 12 (GH12) family proteins secreted by F. graminearum. We established that two GH12 proteins, Fg05851 and Fg11037, have functionally redundant roles in F. graminearum colonization of wheat. Furthermore, we determined that the GH12 proteins Fg05851 and Fg11037 are recognized by the leucine‐rich‐repeat receptor‐like protein RXEG1 in the dicot Nicotiana benthamiana. Heterologous expression of RXEG1 conferred wheat responsiveness to Fg05851 and Fg11037, enhanced wheat resistance to F. graminearum and reduced levels of the mycotoxin deoxynivalenol in wheat grains in an Fg05851/Fg11037‐dependent manner. In the RXEG1 transgenic lines, genes related to pattern‐triggered plant immunity, salicylic acid, jasmonic acid, and anti‐oxidative homeostasis signalling pathways were upregulated during F. graminearum infection. However, the expression of these genes was not significantly changed during infection by the deletion mutant ΔFg05851/Fg11037, suggesting that the recognition of Fg05851/Fg11037 by RXEG1 triggered plant resistance against FHB. Moreover, introducing RXEG1 into three other different wheat cultivars via crossing also conferred resistance to F. graminearum. Expression of RXEG1 did not have obvious deleterious effects on plant growth and development in wheat. Our study reveals that N. benthamiana RXEG1 remains effective when transferred into wheat, a monocot, which in turn suggests that engineering wheat with interfamily plant immune receptor transgenes is a viable strategy for increasing resistance to FHB. [ABSTRACT FROM AUTHOR]

Fe-20Cr-25Ni-Nb steel is an important material for developing highly compact and efficient nuclear power systems by using the supercritical CO2 Brayton cycle. The in-core materials should possess excellent oxidation resistance in a high-temperature CO2 environment. In this work, a new 20Cr-25Ni-Nb steel with a minor Mo addition was developed, and its oxidation behavior was investigated in a pure CO2 environment at 650 °C under 3.5 MPa. The experimental results show that the oxidation kinetics of the steels followed the parabolic law with the test time, and the oxidation process was controlled by diffusion. The 20Cr-25Ni-Nb steel showed better oxidation resistance after Mo addition, which was attributed to the synergistic effects of Nb and Mo during the oxide scale formation process. In a high-temperature environment, the volatilization of Mo promoted the outward diffusion of Nb, resulting in the formation of an Nb-rich layer at the oxide/metal interface, which slowed the outward diffusion of Fe for the formation of the outermost Fe-oxide layer. Although the volatile nature of Mo at high temperatures promoted the outward diffusion of Nb, the addition of Mo had no significant influence on the overall structure of the oxide scales, which consisted of an outer Cr-rich oxide layer and an inner spinel oxide layer. [ABSTRACT FROM AUTHOR]

Structural manipulation of electroactive β-phase of poly(vinylidene fluoride-co-hexafluoropropylene) [P(VDF-HFP)] is of great importance in high-energy-density polymer devices. In this Letter, an efficient way to improve dielectric and energy storage properties of P(VDF-HFP) films by inducing a high β-phase content and lowering the crystallite size through repetitive unipolar nanosecond electric pulses (nsEP) is proposed. It is found that the percentage of the β-phase in P(VDF-HFP) can be significantly enhanced to ∼84% under a low unipolar nsEP of 5 V/mm vs only 35% in pristine P(VDF-HFP). Meanwhile, the orientation of the amorphous chains is also achieved, which improves the dielectric constant, electric breakdown, and energy storage properties of P(VDF-HFP). Specifically, the P(VDF-HFP) film processed under nsEP of 5 V/mm exhibits a high breakdown field of 541 MV/m, and discharged energy density of 14 J/cm3, which is 28.8% and 127% higher than those of the pristine polymer, respectively. This work provides a facile approach to optimize the crystalline morphology of P(VDF-HFP) polymers for dielectric energy storage applications. [ABSTRACT FROM AUTHOR]

Introduction: There is limited basic research on carbon dioxide (CO2) fractional laser, indicating blind spots in CO2 fractional laser treatment of certain diseases. This study aimed to organize previous literature, summarize the current research, and speculate on possible future development. Methods: We searched document data on fractional CO2 lasers from the Web of Science core collection database and retrieved 928 articles from 2004 to 2021. CiteSpace software was used to analyze the main institutions, authors, subject hotspots, and research frontiers in global CO2 fractional laser research. Results: The results revealed that 928 related papers were published in the past 18 years (2004–2021), and the number has increased annually. The publications were written by 3239 authors from 626 institutions in 60 countries/regions. The United States (US) dominates this field (312 documents), followed by Italy (289), and South Korea (88). Lasers in Surgery and Medicine is the journal with the most publications and citations, and Uebelhoer is the central author. The main research hotspots include vulvovaginal atrophy, fractional photothermolysis, keloids, drug delivery, gene expressions, facial acne scarring, resurfacing, vitiligo, and photo damage. Conclusion: Using CiteSpace, this paper draws a map of authors, institutions, and keywords in fractional CO2 laser from 2004 to 2021; summarizes the main authors, institutions, research hotspots, and cutting‐edge topics of global fractional CO2 laser technology in recent years; and summarizes the current application status of global fractional CO2 laser in disease treatment. It also provides new ideas for the future application and research of fractional CO2 lasers. [ABSTRACT FROM AUTHOR]

Polymer materials with excellent physicochemical and electrical properties are desirable for energy storage applications in advanced electronics and power systems. Here, Al2O3@ZrO2 nanoparticles (A@Z) with a core-shell structure are synthesized and introduced to a P(VDF-HFP) matrix to fabricate P(VDF-HFP)/A@Z nanocomposite films. Experimental and simulation results confirm that A@Z nanoparticles increase the crystallinity and crystallization temperature owing to the effect of the refined crystal size. The incorporation of A@Z nanoparticles leads to conformational changes of molecular chains of P(VDF-HFP), which influences the dielectric relaxation and trap parameters of the nanocomposites. The calculated total trapped charges increase from 13.63 μC of the neat P(VDF-HFP) to 47.55 μC of P(VDF-HFP)/5 vol%-A@Z nanocomposite, indicating a substantial improvement in trap density. The modulated crystalline characteristic and interfaces between nanoparticles and polymer matrix are effective in inhibiting charge motion and impeding the electric conduction channels, which contributes to an improved electrical property and energy density of the nanocomposites. Specifically, a ~200% and ~31% enhancement in discharged energy density and breakdown strength are achieved in the P(VDF-HFP)/5 vol%-A@Z nanocomposite. [ABSTRACT FROM AUTHOR]