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BACKGROUND: Leucine (Leu) is an essential amino acid that facilitates skeletal muscle satellite cell differentiation, yet its mechanism remains underexplored. Sestrin2 (SESN2) serves as a Leu sensor, binding directly to Leu, while ribophorin II (RPN2) acts as a signaling factor in multiple pathways. This study aimed to elucidate Leu's impact on mouse C2C12 cell differentiation and skeletal muscle injury repair by modulating RPN2 expression through SESN2, offering a theoretical foundation for clinical skeletal muscle injury prevention and treatment. RESULTS: Leu addition promoted C2C12 cell differentiation compared to the control, enhancing early differentiation via myogenic determinant (MYOD) up‐regulation. Sequencing revealed SESN2 binding to and interacting with RPN2. RPN2 overexpression up‐regulated MYOD, myogenin and myosin heavy chain 2, concurrently decreased p‐GSK3β and increased nuclear β‐catenin. Conversely, RPN2 knockdown yielded opposite results. Combining RPN2 knockdown with Leu rescued increased p‐GSK3β and decreased nuclear β‐catenin compared to Leu absence. Hematoxylin and eosin staining results showed that Leu addition accelerated mouse muscle damage repair, up‐regulating Pax7, MYOD and RPN2 in the cytoplasm, and nuclear β‐catenin, confirming that the role of Leu in muscle injury repair was consistent with the results for C2C12 cells. CONCLUSION: Leu, bound with SESN2, up‐regulated RPN2 expression, activated the GSK3β/β‐catenin pathway, enhanced C2C12 differentiation and expedited skeletal muscle damage repair. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Mental fatigue impairs performance across several sports domains. However, a systematic review on its effects on racket sports performance has been lacking due to the previous scarcity of studies. This review aims to provide a comprehensive review the effects of mental fatigue on racket players' performance, with a discussion of the underlying mechanisms. A thorough search was conducted across five databases, including Web of Science, PubMed, SCOPUS, SPORTDiscus (via EBSCOhost), and the Psychological and Behavioral Science Collection (via EBSCOhost). The PICOS framework established the inclusion criteria: (1) healthy racket sports players; (2) induction of mental fatigue in both field and laboratory settings; (3) comparison of mental fatigue interventions with a control group (e.g., watching a movie or reading a magazine); (4) assessment of performance outcomes, including physical performance, skilled performance, and perceptual-cognitive performance; and (5) randomized controlled trials (RCTs), non-randomized controlled trials (non-RCTs), and non-randomized non-controlled trials. Mental fatigue manipulation, subjective evaluation, and (neuro)physiological markers were synthesized to support the successful induction of mental fatigue. Performance was categorized into tennis, table tennis, badminton, and padel based on the characteristics of specific racket sports domains. Secondary outcomes, such as the rate perception of effort (RPE) and motivation, were synthesized to explain the mechanisms based on the prominent theory of the Psychobiological model of endurance performance. Six studies revealed that mental fatigue impacts stroke performance in table tennis, affecting speed, accuracy, faults, and only second-serve accuracy in tennis. The response time of psychomotor performance increased in table tennis, padel, and badminton. Meanwhile, mental fatigue increased the RPE and remained unchanged in heart rate, blood glucose, and lactate, consistent with the Psychobiological model of endurance performance. Additionally, attention is suggested as a significant underlying psychobiological factor. [ABSTRACT FROM AUTHOR]

We construct a sequence of explicit blow-ups and blow-downs on an irreducible compact Hermitian symmetric spaces |$X$| which transforms it into a projective space of the same dimension. Moreover, this resolves a birational map given by Landsberg and Manivel. Centers of the blow-ups for |$X$| are constructed by loci of chains of minimal rational curves and centers of the blow-ups for the projective space are constructed from the variety of minimal rational tangents of |$X$| and its higher secant varieties. The result was known in the special case where |$X$| is of rank 2 and could be found in Zak's monograph "Tangents and secants of algebraic varieties." [ABSTRACT FROM AUTHOR]

To investigate the desorption behavior of O2 through CO2/N2 injection in the gob of a gassing mine, we focused on the adsorption configuration of coal containing O2–CH4. The mechanism underlying the enhancement of O2 desorption in coal due to CO2/N2 injection was elucidated using the Grand Canonical Ensemble Monte Carlo (GCMC) and Molecular Dynamics (MD) methods. Furthermore, the impact of CH4 on O2 desorption was unveiled by detailed calculations and studies of energy variation, concentration distribution, and diffusion coefficients of oxygen.Our findings indicate the following: (1) CO2 and N2 facilitate the displacement of oxygen primarily by occupying adsorption sites. The CO2–O2 model exhibits a significantly higher concentration of free O2 molecules compared to the N2–O2 model, and the CO2–O2–CH4 model surpasses the N2–O2–CH4 model in free O2 molecules. (2) The total energy of the CO2–O2 model is lower than that of the N2–O2 model, indicating greater stability in the former. Similarly, the total energy of the CO2–O2–CH4 model is lower than that of the N2–O2–CH4 model, highlighting its superior stability. It is concluded that CO2 injection is more effective in promoting oxygen desorption than N2, regardless of the presence of methane. (3) Under equivalent injection pressure, the root mean square displacement of O2 in the CO2–O2 system surpasses that in the N2–O2 system. Furthermore, compared to the N2–O2–CH4 system, the CO2–O2–CH4 system exhibits a larger root mean square displacement of O2, signifying higher O2 molecule activity. The diffusion coefficient of O2 in the CO2–O2 system is higher, underscoring the superior effectiveness of CO2 in promoting O2 desorption.In summary, our research outcomes offer valuable theoretical insights for fire prevention technology in goaf. [ABSTRACT FROM AUTHOR]

With the acceleration of urbanisation, urban areas are subject to the combined effects of the accumulation of various natural factors, such as changes in temperature leading to the thermal expansion or contraction of surface materials (rock, soil, etc.) and changes in precipitation and humidity leading to an increase in the self-weight of soil due to the infiltration of water along the cracks or pores in the ground. Therefore, the subsidence of urban areas has now become a serious geological disaster phenomenon. However, the use of traditional neural network prediction models has limitations when examining the causal relationships between time series surface deformation data and multiple influencing factors and when applying multiple influencing factors for predictive analyses. To this end, Sentinel-1A data from March 2017 to February 2023 were used as the data source in this paper, based on time series deformation data acquired using the small baseline subset interferometric synthetic aperture radar (SBAS-InSAR) technique. A sparrow search algorithm–convolutional neural network–long short-term memory (SSA-CNN-LSTM) neural network prediction model was built. The six factors of temperature, humidity, precipitation, and ground temperature at three different depths below the surface (5 cm, 10 cm, and 15 cm) were taken as the input of the model, and the surface deformation data were taken as the output of the neural network model. The correlation between the spatial and temporal evolution characteristics of the ground subsidence in urban areas and various influencing factors was analysed using grey correlation analysis, which proved that these six factors contribute to some extent to the deformation of the urban surface. The main urban area of Hohhot City, Inner Mongolia Autonomous Region, was used as the study area. In order to verify the efficacy of this neural network prediction model, the prediction effects of the multilayer perceptron (MLP), backpropagation (BP), and SSA-CNN-LSTM models were compared and analysed, with the values of the correlation coefficients of the feature points of A1, B1, and C1 being in the range of 0.92, 0.83, and 0.93, respectively. The results show that compared with the traditional MLP and BP neural network models, the SSA-CNN-LSTM model achieves a higher performance in predicting time series surface deformation data in urban areas, which provides new ideas and methods for this area of research. [ABSTRACT FROM AUTHOR]

Aiming at the problems of small chaotic space and weak chaotic ability of existing chaotic mapping models, a new three-dimensional chaotic mapping model is designed by coupling two-dimensional Henon chaotic mapping model and Sine chaotic mapping model. Aiming at the problem that the security of encryption system will be reduced if the key is reused, this paper designs a new key generation method using Chebyshev mapping and plaintext image. Using the 3D chaotic mapping and key generation method designed in this paper, a color image encryption method is proposed. The results show that the method can encrypt images safely and effectively and protect the security of image information. [ABSTRACT FROM AUTHOR]

Background and Aim: Hepatotoxicity is a well‐defined reaction to methotrexate (MTX), a drug commonly used for the treatment of rheumatoid arthritis and various tumours. We sought to elucidate the mechanism underlying MTX‐induced hepatotoxicity and establish a potentially effective intervention strategy. Methods: We administered MTX to liver cells and mice and assessed hepatotoxicity by cell viability assay and hepatic pathological changes. We determined ferroptosis and ferritinophagy by detecting ferroptosis‐related markers and autophagic degradation of ferritin heavy chain 1 (FTH1). Results: We have shown that hepatocytes treated with MTX undergo ferroptosis, and this process can be attenuated by ferroptosis inhibitors. Interestingly, NCOA4‐mediated ferritinophagy was found to be involved in MTX‐induced ferroptosis, which was demonstrated by the relief of ferroptosis through the inhibition of autophagy or knockdown of Ncoa4. Furthermore, MTX treatment resulted in the elevation of high‐mobility group box 1 (HMGB1) expression. The depletion of Hmgb1 in hepatocytes considerably alleviated MTX‐induced hepatotoxicity by limiting autophagy and the subsequent autophagy‐dependent ferroptosis. It is noteworthy that glycyrrhizic acid (GA), a precise inhibitor of HMGB1, effectively suppressed autophagy, ferroptosis and hepatotoxicity caused by MTX. Conclusion: Our study shows the significant roles of autophagy‐dependent ferroptosis and HMGB1 in MTX‐induced hepatotoxicity. It emphasizes that the inhibition of ferritinophagy and HMGB1 may have potential as a therapeutic approach for preventing and treating MTX‐induced liver injury. [ABSTRACT FROM AUTHOR]

As urban economies flourish and populations become increasingly concentrated, urban surface deformation has emerged as a critical factor in city planning that cannot be overlooked. Surface deformation in urban areas can lead to deformations in structural supports of infrastructure such as road bases and bridges, thereby posing a serious threat to public safety and creating significant safety hazards. Consequently, research focusing on the monitoring of urban surface deformation holds paramount importance. Interferometric synthetic aperture radar (InSAR), as an important means of earth observation, has all-day, wide-range, high-precision, etc., characteristics and is widely used in the field of surface deformation monitoring. However, traditional solitary InSAR techniques are limited in their application scenarios and computational characteristics. Additionally, the manual selection of ground control points (GCPs) is fraught with errors and uncertainties. Permanent scatterers (PS) can maintain high interferometric coherence in man-made building areas, and distributed scatterers (DS) usually show moderate coherence in areas with short vegetation; the combination of DS and PS solves the problem of manually selecting GCPs during track re-flattening and regrading, which affects the monitoring results. In this paper, 45 Sentinel-1B data from 16 February 2019 to 14 December 2021 are used as the data source in the urban area of Horqin District, Tongliao City, Inner Mongolia Autonomous Region, for example. A four-threshold (coherence coefficient threshold, FaSHPS adaptive threshold, amplitude divergence index threshold, and deformation velocity interval) GCPs point screening method for PS-DS, as well as a Small Baseline Subset-Permanent Scatterers-Distributed Scatterers-Interferometric Synthetic Aperture Radar (SBAS-PS-DS-InSAR) method for selecting PS and DS points as ground control points for orbit refinement and re-flattening, are proposed. The surface deformation results obtained using the Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) and the SBAS-PS-DS-InSAR proposed in this paper were comparatively analysed and verified. The maximum cumulative line-of-sight settlements were −90.78 mm and −83.68 mm, and the maximum cumulative uplifts are 74.94 mm and 97.56 mm, respectively; the maximum annual average line-of-sight settlements are −35.38 mm/y and −30.38 mm/y, and the maximum annual average uplifts are 25.27 mm/y and 27.92 mm/y. The results were evaluated and analysed in terms of correlation, mean absolute error (MAE), and root mean square error (RMSE). The deformation results of the two InSAR methods were evaluated and analysed in terms of correlation, MAE, and RMSE. The errors show that the Pearson correlation coefficients between the vertical settlement results obtained using the SBAS-PS-DS-InSAR method and the GPS monitoring results were closer to 1. The maximum MAE and RMSE were 13.7625 mm and 14.8004 mm, respectively, which are within the acceptable range; this confirms that the monitoring results of the SBAS-PS-DS-InSAR method were better than those of the original SBAS-InSAR method. SBAS-InSAR method, which is valid and reliable. The results show that the surface deformation results obtained using the SBAS-InSAR, SBAS-PS-DS-InSAR, and GPS methods have basically the same settlement locations, extents, distributions, and temporal and spatial settlement patterns. The deformation results obtained using these two InSAR methods correlate well with the GPS monitoring results, and the MAE and RMSE are within acceptable limits. By comparing the deformation information obtained using multiple methods, the surface deformation in urban areas can be better monitored and analysed, and it can also provide scientific references for urban municipal planning and disaster warning. [ABSTRACT FROM AUTHOR]

The protein 4.1R is an essential component of the erythrocyte membrane skeleton, serving as a key structural element and contributing to the regulation of the membrane's physical properties, including mechanical stability and deformability, through its interaction with spectrin–actin. Recent research has uncovered additional roles of 4.1R beyond its function as a linker between the plasma membrane and the membrane skeleton. It has been found to play a crucial role in various biological processes, such as cell fate determination, cell cycle regulation, cell proliferation, and cell motility. Additionally, 4.1R has been implicated in cancer, with numerous studies demonstrating its potential as a diagnostic and prognostic biomarker for tumors. In this review, we provide an updated overview of the gene and protein structure of 4.1R, as well as its cellular functions in both physiological and pathological contexts. [ABSTRACT FROM AUTHOR]

A new aminosilane external donor named piperidine methyl dimethoxysilane (Donor-PMe) was firstly synthesized, and then was used as external donor on propylene polymerization with MgCl2-supported Ziegler-Natta catalyst. The effects of Donor-PMe on the catalytic activity, isotacticity, molecular weight distribution, isotactic sequence length, isotactic sequence distribution of polypropylene were studied by differential scanning calorimetry (DSC), gel permeation chromatography (GPC), and self-nucleation and annealing (SSA), respectively. It was found that it was conducive to improving the activity and stereoregularity of catalyst when the new aminosilane Donor-PMe was used as external donor with MgCl2-supported Ziegler-Natta catalyst. The catalytic activity of the Ziegler-Natta catalyst and the isotacticity of PP prepared by Donor-PMe increased with the increase of Si/Ti ratio on propylene polymerization.The GPC results showed that the molecular weight distribution of polypropylene was about 6.7, which was broader than that of industrial homo-polypropylene about 3.0. The SSA results showed that the relative contents of the highest isotactic component and the lamellar thickness in the PP chain gradually increased with the increase of Si/Ti of Donor-PMe, indicating the isotactic sequence length of polypropylene got longer with the increase of Si/Ti ratio of Donor-PMe. Meanwhile, the lamellar thickness distribution of polypropylene became broader, revealing the isotactic sequence length distribution of polypropylene got broader, indicating there were more higher isotactic sequence length in PP chain. [ABSTRACT FROM AUTHOR]

Straw biochar, as an emerging adsorbent, boasts advantages such as abundant availability, renewability, and cost-effectiveness, making it highly promising in treating heavy metal wastewater. This paper presents a comprehensive review of the preparation methods for straw biochar materials, delves into the adsorption mechanism of straw biochar for heavy metals, discusses its application in heavy metal wastewater treatment, and also highlights areas for further in-depth research, including the adsorption mechanism, adsorption capacity, and regeneration performance, in lights of existing challenges in their preparation and application. This paper deepens the scientific understanding of the action mechanism of straw biochar in heavy metal wastewater treatment, and provides an important reference for the development of straw biochar materials and application of straw biochar materials in the purification of heavy metal wastewater. [ABSTRACT FROM AUTHOR]