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Liver fibrosis is a key contributor to hepatic disease-related mortality. Exosomes derived from mesenchymal stem cells (MSCs) have been revealed to improve liver fibrosis. To explore the effect and mechanism of MSC-derived exosomal miR-26a on liver fibrosis, exosomes were separated from bone marrow-derived MSCs (BMSCs) and used to treat with LX2 cells. The miR-26a level was decreased in BMSC-derived exosomes. Treatment with exosomes isolated from human BMSCs transfected with miR-26a mimics (miR-26a mimic-Exo) decreased the 5-ethynyl-2'-deoxyuridine-positive cell rate, the protein level of α-SMA and collagen I, and the glutathione (GSH) level but enhanced the apoptosis rate and the reactive oxide species (ROS) level in LX2 cells, which were reversed by the treatment of deferoxamine. Mechanically, miR-26a directly bound SLC7A11 mRNA and negatively modulated the level of SLC7A11 in LX2 cells. Overexpression of SLC7A11 reversed the miR-26a mimic-Exo-induced alterations in the level of ROS, Fe2+, malonaldehyde, and GSH in LX2 cells. In vivo, miR-26a mimic-Exo decreased the level of SLC7A11 and attenuated CCL4-induced liver fibrosis. Collectively, miR-26a mimic-Exo induced ferroptosis to alleviate liver fibrosis by regulating SLC7A11, which may provide new strategies for the treatment of liver fibrosis, and even other relevant diseases.

AbstractBackground Data on the characteristics and treatment outcomes of super-responders and non-super-responders in psoriasis under adalimumab treatment are limited.Methods A retrospective analysis from psoriatic patients treated with adalimumab was compared to characterize super-responders vs non-super-responders’ groups, identify factors associated with super response, and assess treatment outcomes after switching.Results 15 out of 70 (21.4%) patients were categorized as super-responder. The proportion of patients achieving a PASI 100 response was significantly higher in super-responders than non-super-responders at weeks 12, 24, and 52. Female sex and Charlson Co-morbidity Index were significantly associated with super-responders. A high level of high-density lipoprotein was independently associated with PASI 90 response at weeks 24 and 52. Additionally, nearly 35%–43% of non-super-responders switching to interleukin-17A (IL-17A) inhibitors may achieve a PASI 100 response at week 12. In contrast, all super-responders switching to IL-17A inhibitors achieved a PASI 100 response at week 4.Conclusions Super-responders treated with adalimumab have a higher rate of being female and fewer comorbidities. And super-responders have better PASI responses than non-super-responders, whether the patients were treated with adalimumab or switched to IL-17A inhibitors.

BackgroundThe interplay between teaching engagement and performance has garnered attention in both theoretical and empirical research, primarily due to its influence on student academic achievement, teacher well-being, and the realization of institutional goals. This is especially pertinent in the realm of preschool education, where the scope of learning extends beyond academic content to encompass the broader socialization of children. Drawing from Affective Neuroscience research, this study investigates the role of affective tendencies as mediators in the relationship between work engagement and job performance.ObjectiveThe primary aim of this research is to examine a chain mediation model that hypothesizes the predictive role of teacher engagement. This model posits the intermediary influence of four basic emotions—CARING, SEEKING, ANGER, and FEAR—followed by the mediating effect of job satisfaction on teacher job performance.MethodThe study utilized a sample of 842 Chinese preschool teachers. Data were collected through an online questionnaire, employing a time-lagged design. The analysis was conducted using Model 80 of the PROCESS Macros.ResultsThe findings reveal that both positive and negative emotions significantly predict teachers’ job satisfaction. However, job satisfaction does not influence job performance. The analysis confirmed the direct and total effects of teacher engagement, as well as the indirect effects, particularly through the positive emotion of Caring.ImplicationsThe results are instrumental in informing and refining interventions designed to enhance teacher engagement and performance, underscoring the importance of emotional factors in the educational environment.

The purpose of this research is to discuss and analyze the extent of the influence of using the bosu ball for squat activities on the lower limb. This research will use a quantitative and descriptive research approach. Surface electromyography will be used to measure different squat positions between 900 and 1400. The measurement compares the squat position without a bosu ball with the squat position using a bosu ball. The results of the surface electromyography recording on muscle activity at 900 on the four muscles indicate that the Rectus Femoris (RF) muscle experienced an increase in the percentage of 18.33%, the Vastus Medialis Oblique (VMO) was 77.92%, the Biceps Femoris (BF) was 24.88%, and the Semitendinosus was 79.63%. Meanwhile, on the 1400 muscle activity, the Rectus Femoris (RF) muscle increased by 31.58%, the Vastus Medialis Oblique (VMO) by 20.19%, the Biceps Femoris (BF) by 28.07%, and the Semitendinosus by 42.93%. This study concludes is that differences in muscles will certainly provide different results as well. In the squat activity at an angle of 900, it shows that the most dominant muscle is the Semitendinosus and the Vastus Medialis Oblique (VMO), while in the squat activity at an angle of 1400, it shows that the most dominant muscle is the Semitendinosus and the Rectus Femoris (RF). So, from the squat angle position, some muscles have their own roles and functions, with the Vastus Medialis Oblique (VMO) muscle having the most dominant result.

Ensuring the safety of tunnel structures in unique underwater environments is of paramount importance. This study focuses on the entrance section of a river-crossing tunnel, characterized by shallow burial depths with significant variations. The tunnel structure faces challenges related to structural weakening, and its deformation response exhibits specific characteristics under seismic loads. Numerical simulation software was employed to model and calculate the deformation response of the shallowly buried entrance section under seismic load conditions, assessing the impact of changes in tunnel structural strength and burial depth. The results reveal the following key findings: (1) As the tunnel structure weakens, structures of varying strengths primarily experience vertical deformation under seismic loads, followed by horizontal deformation. Furthermore, as the tunnel structure’s strength decreases, it exhibits an increasing trend in deformation. Routine maintenance should prioritize locations where the tunnel structure weakens, implementing timely reinforcement measures to ensure adequate load-bearing capacity. (2) Considering the influence of tunnel structural burial depth, lateral deformation values rank in descending order from largest to smallest, including the tunnel bottom, middle carriageway, middle of the tunnel, and tunnel vault, while the overall lateral deformation of the tunnel is not significant, it decreases as the structural burial depth increases. (3) In relation to tunnel structural burial depth, vertical deformation values generally exceed horizontal deformation values. Sections with the highest to lowest deformation values are the tunnel bottom, middle lane of the tunnel, middle of the tunnel, and position of the tunnel vault. With increasing burial depth, the vertical deformation values decrease at a slower rate than horizontal deformation. The tunnel structure demonstrates a higher sensitivity of lateral deformation to changes in burial depth factors.

The traditional RGB-based action recognition method is vulnerable to background factors such as illumination and occlusion, which makes the recognition accuracy and real-time performance low. In order to solve the above problems, a 2D skeleton action recognition method incorporating a hierarchical attention mechanism was proposed. Firstly, the human skeleton joints in the video were extracted using the human pose estimation algorithm OpenPose. Secondly, the missing and abnormal points in the extracted skeleton data were pre-processed by the mean-completion method and exponential smoothing method. Finally, a network model based on CNN-LSTM fused with hierarchical attention mechanism, CNN-HALSTM, was constructed to realize action classification. The results show that the recognition accuracy of this method in interactive motion and KTH data sets is 96.73% and 98.35%, and the model parameters are significantly reduced, which has the advantage of real-time performance and is better than other methods of the same type.

The coronavirus disease 2019 (COVID-19) pandemic has caused immense losses in human lives and the global economy and posed significant challenges for global public health. As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, has evolved, thousands of single nucleotide variants (SNVs) have been identified across the viral genome. The roles of individual SNVs in the zoonotic origin, evolution, and transmission of SARS-CoV-2 have become the focus of many studies. This review summarizes recent comparative genomic analyses of SARS-CoV-2 and related coronaviruses (SC2r-CoVs) found in non-human animals, including delineation of SARS-CoV-2 lineages based on characteristic SNVs. We also discuss the current understanding of receptor-binding domain (RBD) evolution and characteristic mutations in variants of concern (VOCs) of SARS-CoV-2, as well as possible co-evolution between RBD and its receptor, angiotensin-converting enzyme 2 (ACE2). We propose that the interplay between SARS-CoV-2 and host RNA editing mechanisms might have partially resulted in the bias in nucleotide changes during SARS-CoV-2 evolution. Finally, we outline some current challenges, including difficulty in deciphering the complicated relationship between viral pathogenicity and infectivity of different variants, and monitoring transmission of SARS-CoV-2 between humans and animals as the pandemic progresses.

Second harmonic generation through nonlinear nano-photonic structures is important in both classical and quantum applications. It is commonly expected that the second harmonic frequency can always be generated as long as appropriate quadratic nonlinearity is provided by the material and the phase-matching condition is satisfied. Here, we present an anomaly to this common wisdom by showing that second-harmonic dipoles generated in a nonlinear photonic crystal slab can be completely nonradiative. As a result, no energy is transferred from the fundamental frequency to the second harmonic even when the phase-matching condition is satisfied – a phenomenon we call “resonance-forbidden second-harmonic generation”. Through numerical simulation, we identify two mechanisms that can achieve this phenomenon: symmetry protection and parameter tuning. The finite-size effect and the topological origin of this phenomenon are also discussed.

Climate change and human activity are two linked factors that alter the spatiotemporal distribution of the available water. Assessing the relative contribution of the two factors on runoff changes can help the planners and managers to better formulate strategies and policies regarding regional water resources. In this work, using two typical sub-basins of the Yellow River as the study area, we first detected the trend and the breakpoint in the annual streamflow data with the Pettitt test during the period 1964–2011. Next, a Budyko-based climate elasticity model and a monthly hydrological model were employed as an integrated method to distinguish the relative contributions of climate change and human activities to the long-term changes in runoff. The results showed that a significant decline in the annual runoff occurred in the two sub-basins during the study period, and the abrupt change point in the annual runoff at the two sub-basins both occurred in 1997. The conceptual hydrological model performed well in reproducing monthly runoff time series at the two sub-basins. The Nash-Sutcliffe efficiency (NSE) between observed and simulated runoff during the validation period exceeds 0.83 for the two sub-basins. Climate elasticity method and hydrological model give consistent attribution results: human activities are the major drivers responsible for the decreased annual runoff in the Ten Great Gullies Basin. The relative contributions of climate change and human activities to the changes in the annual runoff were 22–32% and 68–78%, respectively.

This paper aims to investigate the internal mechanisms of bottlenecks in bike-sharing travel. We perform kernel density analysis to obtain analysis points and areas designated by buffer areas. Additionally, we improve the spatial lag model through Tobit regression, so as to avoid the interference of autocorrelation and to set reasonable constraints for dependent variables. The proposed model distinguishes between bike-sharing demand determined by land use and other built environmental factors, which helps to define and identify bottlenecks in bike-sharing travel. Based on a Bayesian network fault tree, we define the diagnosis mode of evidence nodes to calculate the posterior probabilities and to determine the most sensitive factors for bottlenecks. We use Beijing city as the case study. The results show that the most sensitive factors that induce bottlenecks in bike-sharing travel are few subway stations, few bus stops, few bus lines, a low density of bike lanes, and more serious home–work separation. The findings presented here can enhance the generation of bike-sharing trips in response to bike-sharing development and contribute to adjusting the urban structure and reconstructing the green infrastructure layout.

Pyrite (FeS2) is considered to be an excellent electrode material candidate for energy storage devices because of its abundant resources, cost effectiveness, environmental friendliness and high theoretical capacity of 894 mA·h·g-1 based on conversiontype reactions.However, transition metal sulfides (TMSs), includingFeS2, suffer from low electronic conductivity, sluggish Li ion transfer kinetics, and severe volume change while charging and discharging, which contribute to the sharp decline in capacity as well as limit its application as electrode material for secondary batteries.Downsizing TMS powders to the nanoscale becomes a common strategy to mitigate the volume change and maximize the proportion of active material involved in the electrochemical process.However, nanostructures lead to a serious interphase detrimental reaction, dissolution of the polysulfide intermediates, and low volumetric energy density.Therefore, micron particles are critical to the design of high energy density active material in view of industrial applications.In this study, a facile hydrothermal method has been successfully developed to synthesize a novel mesoporous composite of core-shell FeS2 micron spheres with multi-walled carbon nanotubes (C-S-FeS2@ MWCNT).The protective layer is constructed on FeS2 micron spheres consisting of the approximately 350 nm-thickness shell stacked by nanosheet FeS2 particles and the reticular MWCNTs anchored via chemical binding.The FeS2 content is determined using thermogravimetric analysis to be 73.4% of the C-S-FeS2@ MWCNT composite, which is higher than the value of the reported compound material with nanopowder.The unique architecture with abundant functional groups and pore structures not only provides the Li+ ion diffusion pathway but also buffers volume expansion during cycling.The galvanostatic circulation tests indicate that the C-S-FeS2@ MWCNT electrode delivers a high reversible capacity of 638 mA·h·g-1 in 250 cycles at a current density of 200 mA·g-1 and exhibits a significantly improved rate performance.This work demonstrates a new method to develop TMSmicron electrode material with high volumetric energy density.

Aiming at of solving the cracking problem of an alternator bracket. Firstly, the engine time domain-acceleration curve were tested, and they were converted to frequency domain acceleration curve. The alternator bracket was frequency response analyzed based on the frequency domain acceleration curve, the analysis results show that the maximum stress value exceeded the yield strength of the material. Secondly, the alternator bracket was vibration fatigue analyzed by adopting power spectrum density function, the analysis results show that the minimum life was lower than target, and it was consistent with the strength analysis weak region and actual failure position. Thirdly, the alternator bracket was optimal designed by adopting large scale generalized reduced gradient algorithm, it can meet fatigue and strength performance requirements after optimization. Lastly, the alternator bracket optimization scheme was certificated by vehicle road test, the test results show that the alternator bracket vibration amplitude is obviously decreased, and the alternator bracket cracking is avoided, so the cracking problem is effectively solved. A scientific references are provided for the high frequency response bracket failure solution by the analysis method and its optimization method.

Underground gas storage as the main system of natural gas peak regulation, its construction demand continues to grow in the world. Different from other common oil and gas well strings, the service time of the gas storage string is longer and the service environment is worse, which poses a greater challenge to the integrity design of the string joint. In this paper, starting from the most important connection and sealing performance of the pipe string joint, aiming at the special threaded joint suitable for the gas storage pipe string, based on the analysis of the force and deformation of the gas storage pipe string, the joint connection strength and sealing performance of the pipe string joint under the axial load, internal and external pressure and long-term alternating load are considered. Based on the FINITE element model of VAM TOP special threaded joint, the deformation and sealing behavior of the joint under different composite loads were numerically simulated, and the variation law of joint connection stress and sealing contact pressure with load was obtained, and the most vulnerable failure position and the most dangerous working condition were analyzed.

Objective To explore the role of high mobility group B1 （HMGB1） protein in the post-traumatic endoplasmic reticulum stress （ERS） in rat lung tissues. Methods The rat model of acute lung injury was established by crushing the hind limbs of rats with standard weight. The first experiment was to divide rats into postural control group and crush groups （6 h, 18 h and 30 h after crushing）. The second experiment was to divide rats into postural control group, 18 h crush group, HMGB1 inhibitor sodium butyrate （SB） group and 18 h crush+SB group. The protein expression changes of HMGB1 and ERS- related proteins （GRP78, caspase-12, CHOP and IRE1α） in rat lung tissues were detected with Western blotting. Meanwhile, the pathological changes of rat lungs were observed by HE stain. Results Compared with the postural control group, the expression levels of ERS-related proteins （GRP78, caspase-12, CHOP and IRE1α） and HMGB1 protein in rat lung tissues by crushing the hind limbs of rats were obviously increased. The protein levels reduced at 30 h after crushing but were still higher than those of postural control group and obvious pathological changes of acute lung injury were observed simultaneously in rats. Compared with the 18 h crush group, the expression levels of the ERS-related proteins and HMGB1 protein in rat lung tissues were attenuated in 18 h crush+SB group, and the pathological changes of rat lung injury began to alleviate. Conclusion HMGB1-ERS pathway activated by traumatic stress can lead to acute lung injury in rats.

To study the fractal characteristics of stylolite and its influence on the strength of limestone, the fractal dimension of horizontal stylolite and vertical stylolite was analyzed using the power spectral density method and the digital image box dimension method based on digital image processing technology. The influence of the stylolite on the limestone strength and the crack evolution process of the limestone were studied through experimental tests and numerical simulations. The results show that the fractal dimension of stylolite lies between 1 and 2, indicating that the stylolite is a self-affine fractal structure in nature, and the vertical stylolite has a large roughness. The stylolite weakens the strength of limestone by about 20% on average, the strength of limestone with different inclinations of stylolite shows less obvious anisotropy and stylolite has negligible effect on the elastic modulus of limestone. In the failure process of limestone, crack initiation and propagation in limestone is closely related to the stylolite, and the stylolite accelerates the damage and failure of the limestone. Numerical simulations show that the thickness, position, numbers, and fractal dimension of the stylolite have significant effect on the strength of the limestone.

Atmospheric rivers (ARs), intrusions of warm and moist air, can effectively drive weather extremes over the Arctic and trigger subsequent impact on sea ice and climate. What controls the observed multi-decadal Arctic AR trends remains unclear. Here, using multiple sources of observations and model experiments, we find that, contrary to the uniform positive trend in climate simulations, the observed Arctic AR frequency increases by twice as much over the Atlantic sector compared to the Pacific sector in 1981-2021. This discrepancy can be reconciled by the observed positive-to-negative phase shift of Interdecadal Pacific Oscillation (IPO) and the negative-to-positive phase shift of Atlantic Multidecadal Oscillation (AMO), which increase and reduce Arctic ARs over the Atlantic and Pacific sectors, respectively. Removing the influence of the IPO and AMO can reduce the projection uncertainties in near-future Arctic AR trends by about 24%, which is important for constraining projection of Arctic warming and the timing of an ice-free Arctic.

The process of electroless copper plating in an EDTA/THPED dual-ligand system using sodium 3,3'-dithiodipropane sulfonate (SPS) as an additive was studied by the electrochemical method. The mixed potential of the system was measured as a function of time, and results indicate that addition of SPS gradually shifts the mixed potential toward the negative direction without saltation. The dual-ligand electroless copper system was then tested by linear sweep voltammetry, and SPS is found to accelerate both cathodic and anodic polarization. The additive mainly influences the anodic polarization of the formaldehyde oxidation process and the rate of copper deposition is improved to a certain extent. The surface morphology and texture of the resulting plated copper were also analyzed by scanning electron microscope, energy dispersive spectrometer and X-ray diffraction, and a high-purity product without Cu2O inclusions is confirmed. Moreover, the X-ray diffraction results of the electroless copper layers show that addition of SPS favors the formation of the preferred orientation on the (200) lattice plane.

NiCoCrAl coatings containing Y and Y oxide were made using vacuum plasma deposition and high-velocity oxygen fuel respectively, high temperature oxidation dynamics and cross-section microstructures of NiCoCrAl+Y and NiCoCrAl+Y(O) coatings in Ar-16.7%O2, Ar-3.3%H2O and Ar-0.2%H2-0.9%H2O at 1100℃ were investigated by differential thermal analysis (DTA) and optical and electron microscope. The influencing mechanism of Y oxide on the oxidation of coatings at different atmosphere was compared by computation using First-Principles. The results show that Al2O3 layer on NiCoCrAl+Y coatings has more holes for internal oxidation on account of the element Y diffusion and enrichment on the interface. In addition, steam can promote the internal oxidation. While a thinner and uniform alumina form on NiCoCrAl+Y(O) coatings because element Y is pinned by oxygen atoms during the preparation of coatings. Water vapor has less influence on protective alumina formation on the NiCoCrAl+Y(O) coating. Therefore, oxidation behavior of NiCoCrAl coatings vary in composition and structure in different oxidizing atmosphere. Besides, Y and Y-enrichment oxides have key influences on the microstructure and the growth rate.

Mammalian target of rapamycin (mTOR) is a serine/threonine protein kinase and activation of its signal pathway plays an important role in regulating protein growth and synthesis as well as cell proliferation and survival. In the present study, we examined the contribution of mTOR and its downstream products to brain injuries and neurological deficiencies after cardiac arrest (CA) induced-transient global ischemia. CA was induced by asphyxia followed by cardiopulmonary resuscitation (CPR) in rats. Our results showed that expression of p-mTOR, mTOR-mediated phosphorylation of 4E-binding protein 4 (4E-BP1) and p70 ribosomal S6 protein kinase 1 (S6K1) pathways were amplified in CA rats compared to their controls. Blocking mTOR using rapamycin attenuated upregulation of pro-inflammatory cytokines (namely IL-1β, IL-6 and TNF-α), and Caspase-3, indicating cell apoptosis and also promoting the levels of vascular endothelial growth factor (VEGF) and its subtype receptor VEGFR-2 in the hippocampus. Moreover, the effects of rapamycin were linked to improvement of neurological deficits and increased brain water content observed in CA rats. In conclusion, activation of mTOR signal is engaged in pathophysiological process during CA-induced transient global ischemia and blocking mTOR pathway plays a beneficial role in regulating injured neuronal tissues and neurological deficits via PIC, apoptotic Caspase-3 and VEGF mechanisms. Targeting one or more of these specific mTOR pathways and its downstream signaling molecules may present new opportunities for neural dysfunction and vulnerability related to transient global ischemia.

Firstly，DFIG basic structure of grid side converter was analyzed according to basic principles of voltage converter, and a mathematical model of grid side converter was established in the three-phase stationary coordinate system and the two-phase rotating coordinate system respectively. Then use the grid voltage oriented vector control strategy based On dq coordinate model of the grid side converter and its essential principles and realization scheme were introduced. Finally，SVPWM，Park，control systems and other power electronics model were built in matlab/simulink，converter was simulated based On vector control strategy under rectifier state and inverter state respectively. The simulation results show that the control strategy has a good dynamic response，and by choosing the appropriate inductance，capacitance，the network side current will reach stable state quickly with smooth waveform and small harmonic，while the DC voltage will reach stable value quickly with small overshoot.

In order to research the shiftability of a transmission synchronizer,the synchronizer model,shifting control mechanism model and shifting robot model are built by adopting Simulation X integrated ADAMS,ABAQUS and CATIA based on shifting control and test specification of synchronous durability test bench,two kinds of shifting process conditions of 1-2 upshift and 2-1 downshift are simulated,so the shifting force,shifting displacement and input shaft speed are obtained. The simulation data are compared with test data,the analysis results show that they are basically identical,the difference is that the simulation shifting time is slightly ahead of the bench test time,the feasibility and accuracy of simulation results are verified.