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Electrical current can effectively improve the plasticity of metallic materials. The tensile deformation behavior of Al alloys under the pulsed electrical current assisted quasi-static unidirectional tension (EAT) has been investigated. Materials under the EAT exhibits periodic electro-softening and strain-hardening behaviors, i.e., a ratchet shape mechanical response. However, establishing a constitutive model to accurately predict the ratchet shape mechanical behavior, especially during the EAT interval, and accurately predicting the strain-hardening behavior of materials are critical issues that need to be solved urgently. In this study, based on the Taylor polycrystalline model, thermal activation theory and dislocation density evolution theory, a two-parameter dislocation density electroplasticity constitutive model with forward and reverse dislocation density evolution was developed to describe the periodic coupling effect of the electro-thermal-mechanical fields during EAT. The tensile deformation behaviors of AA 6061-T6 and AA 7075-T6 under the effect of a pulsed electrical current were quantitatively predicted using the proposed constitutive model. The results show that the correlation coefficient between the predicted and experimental results of the constitutive model can reach 0.84–0.99, implying that the proposed constitutive model can accurately predict the complex electroplasticity behavior of Al alloys during EAT.

A novel process involving cold deformation, cyclic solution, and two-step aging is developed for simultaneously improving the strength and plasticity of 18Ni(350) maraging steel. The strengthening and toughening mechanisms are elucidated by microstructural characterization and tensile property measurements. Cold deformation and cyclic solution refine the final martensite grains. In addition, two-step aging ensures the formation of numerous fine precipitates and a small amount of fine reversed austenite. Ultra-high strength is achieved by a combination of solid-solution, grain refinement, dislocation, and precipitation strengthening, with the latter having the largest contribution. Compared with the traditional process, the UTS and elongation are increased by 9.13% and 22.83%, respectively, to 2511 MPa and 5.81%, demonstrating the effectiveness of this novel process.

The urgent need of improving energy efficiency accelerates the development of lightweight magnesium alloy, especially for high-performance wrought magnesium alloy. In this research, multi-degrees of freedom (multi-DoF) forming process as a novel severe plastic deformation technique was applied to the forged-annealed WE43 magnesium alloy plates. The effect of deformation amounts ranging from 10% to 40% on microstructure and mechanical property of the experimental material was investigated in detail. Initially forged-annealed WE43 magnesium alloy is composed of rodlike-shaped Mg12Nd and cuboid-shaped Mg24Y5 at the grain boundaries as well as globular-shaped Mg41Nd5 inside the grains. Multi-DoF forming process results in remarkable microstructure change, which is characterized by increasing dissolution of these second phases, grain refinement, formation of twins and disappearance of basal texture in WE43 magnesium alloy with deformation amounts increasing. Compared with the initial forged-annealed one, the multi-DoF formed WE43 magnesium alloy displays an increasing tensile strength but a decreasing plasticity with deformation amounts increasing. The increasingly improved strength is mainly attributed to the joint contribution of increasing solution strengthening, fine-grained strengthening and work hardening, while the increasingly decreased plasticity is mainly attributed to the increasing dislocation despite the basal texture disappearing. This research will provide a novel method of fabricating high-performance wrought magnesium alloy.

Titanium alloys are extensively utilized in the aerospace industry due to their exceptional strength and resistance to corrosion. However, litmited performance and high dispersion has always existed for the traditional manufacturing process. A novel Electroshock Treatment (EST) procedure proposed by author's team can synergistically improve the mechanical properties and its consistency of titanium alloys under limited temperature rise, but the relevant mechanism is not yet clear. In present work, the effects of various EST conditions on the mechanical characteristics were investigated by uniaxial tensile testing, and the effect mechanism was revealed using multi-scale microstructure characterization of titanium alloys, such as SEM, EBSD and TEM. The uniaxial tensile test results show that, compared with the sample without EST, the average elongation after fracture improved by 12.5%, the strength-plastic product improved by 16.1%, and the consistency of UTS and elongation after fracture improved by 63.4% and 57.1%, respectively, with a slight increase of tensile strength (30 MPa) after appropriate treatment (current density of 0.93 × 108A/m2, and pulse duration of 300 ms). The multi-scale microscopic characterization reveals a more uniform distribution of stress concentration in TC11 titanium alloy following the appropriate EST process. Besides, the entanglement of dislocations is reduced with some dislocations being annihilated. Especially, the remaining dislocations undergoing orderly rearrangement at grain boundaries after EST. The homogenization of local lattice distortion distribution and orderly rearrangement of dislocations at grain boundaries are the primary factors contributing to the comprehensive improvement in the mechanical properties and consistency of TC11 Titanium alloy.

Adhesive bonding is widely used in aeronautical carbon fiber-reinforced polymer (CFRP)/titanium (Ti) alloy hybrid structures to satisfy the demands of high-strength and lightweight. The physicochemical properties of adherend surfaces significantly impact the bonding performance. In this study, laser-induced surface reconstruction (LISR) was designed for the reliable joining of Ti alloy and CFRP. A three-level-three-factor central composite design (CCD) approach-based response surface methodology (RSM) analysis was applied to statistically specify parameter optimization of the laser energy output. Surface morphology and wettability of CFRP ablated were studied. Chemical compositions were determined by X-ray photoelectron spectroscopy (XPS). Tensile-shear tests were performed, and fractured surfaces were analyzed. The tensile shear strength with LISR process has been improved by 19.1%, in comparison with that of mechanical grinding treatment. The cross-like texture based on designed geometric configuration was fabricated without damaging the underlying fibers, thus increasing the surface roughness and contact area at interface. The wettability transition mechanism was investigated, demonstrating that the hydrophilicity of reconstructed surfaces primarily attributes to the more polar groups (C–O, CO, etc.) on CF surfaces. This study provides a reliable surface treatment method for fabricating high-performance composite structures by adhesive bonding.

Abstract Meningitis induced by Pasteurella multocida has been substantially described in clinical practice in both human and veterinary medicine, but the underlying mechanisms have not been previously reported. In this study, we investigated the influence of P. multocida infection on the permeability of the blood–brain barrier (BBB) using different models. Our in vivo tests in a mouse model and in vitro tests using human brain microvascular endothelial cell (hBMEC) model showed that P. multocida infection increased murine BBB permeability in mice and hBMEC monolayer permeability. Furthermore, we observed that P. multocida infection resulted in decreased expression of tight junctions (ZO1, claudin-5, occludin) and adherens junctions (E-cadherin) between neighboring hBMECs. Subsequent experiments revealed that P. multocida infection promoted the activation of hypoxia inducible factor-1α (HIF-1α)/vascular endothelial growth factor A (VEGFA) signaling and NF-κB signaling, and suppressed the HIF-1α/VEGFA significantly remitted the decrease in ZO1/E-cadherin induced by P. multocida infection (P

BackgroundElevated plasma homocysteine (Hcy) has been reported as a risk factor for cognitive impairment in the general population. However, there are conflicting results regarding the relationship between Hcy and cognitive impairment across various cognitive domains in Parkinson’s disease (PD).ObjectiveThis study aims to explore the association between plasma Hcy levels, cognitive impairment, and dysfunction in various cognitive domains among PD patients with and without mild cognitive impairment (MCI).MethodsA total of 101 PD patients underwent plasma Hcy measurement, comprising 50 PD-MCI patients and 51 patients with normal cognition (PD-NC). A battery of neuropsychological tests was administered to assess different cognitive domains. Adjusted generalized linear models were used to assess the correlations between Hcy levels and cognitive functions.ResultsAs anticipated, PD-MCI patients demonstrated a significant decline in cognitive function across all five cognitive domains (memory, executive function, attention/working memory, language, and visuospatial function). Elevated plasma Hcy levels (≥ 10 μmol/L) were associated with a higher odds of PD-MCI, even within the normal range of Hcy levels (< 15 μmol/L). After adjusting for confounding factors, a negative correlation was observed between plasma Hcy levels and the performance on specific cognitive tests evaluating executive functions in PD, such as the Stroop Color-Word Test-C (β = −1.123, 95% CI = −1.845 ∼−0.401, p = 0.0023).ConclusionThis study underscores a significant link between plasma Hcy levels and PD-MCI, particularly concerning executive dysfunction, even within the normal range of Hcy levels (< 15 μmol/L).

Accumulation of pathological tau is one of the primary causes of Primary Progressive Aphasia (PPA). The glymphatic system is crucial for removing metabolite waste from the brain whereas impairments in glymphatic clearance in PPA are poorly understood. Thus, this study aims to investigate the role of dysregulated macroscopic cerebrospinal fluid (CSF) movement in PPA. Fifty-six PPA individuals and ninety-four healthy controls were included in our analysis after excluding those with excessive head motions during the scan. The coupling strength between blood-oxygen-level-dependent (BOLD) signals in the gray matter and CSF flow was calculated using Pearson correlation and compared between the groups. Its associations with clinical characteristics including scores from Clinical Dementia Rating (CDR), Mini-Mental State Exam, Geriatric Depression Scale and with morphological measures in the hippocampus and entorhinal cortex were examined. PPA subjects exhibited weaker global BOLD-CSF coupling compared to HCs, indicating impairments in glymphatic function in the patients (p = 0.01). In the PPA but not HC group, global BOLD-CSF coupling correlated with the CDR scores (p = 0.04) and hippocampal volume (p = 0.009). The observed decoupling between global brain activity and CSF flow and its association with symptomatology and brain structural changes in PPA converges with previous reports on the same measure in other neurodegenerative diseases. These findings support the potential role of global BOLD-CSF coupling as a noninvasive marker for glymphatic dysregulation in PPA.

The evolution of lattice dislocations in metals can be induced by electric current. However, the effect of electric current on the interaction between lattice dislocations and grain boundaries (GBs) remains unclear. Herein, we investigate the evolution of lattice dislocations and grain boundary dislocations (GBDs) induced by electric current in M50 steel via in-situ TEM characterization, density functional theory (DFT) calculations, and molecular dynamics (MD) simulations. Our findings reveal that electric current induces the directional slip of lattice dislocations towards GBs, while the reduction of GB contrast is attributed to the decomposition and reorganization of GBDs. DFT calculations demonstrate that electric current enhances the force on atoms in defect regions. These in-situ TEM observations are well reproduced by MD simulations incorporating electric current, which include a virtual temperature rise at defect regions to reflect the electric current force on defect atoms. Based on these observations, we propose a novel GB accommodation model under electric current. These results provide valuable insights into the mechanisms by which electric current tailors lattice dislocation behavior and enhances GBDs ordering in metallic materials.

Al7075 sheets are usually manufactured by plastic deformation process owing to its effective strength enhancement, but the high strength and low plasticity restrict the application of plastic deformed Al7075 sheets. This study applies hot multi-DoF (degrees of freedom) forming process to manufacturing Al7075 sheets, and investigates the microstructure and mechanical property evolution of Al7075 sheets during the forming process. The results show that grain size decreases from 21.37 μm to 7.27 μm, which is mainly because that the strong multi-directional metal flow could lead to intensive lattice rotation and dislocation movement throughout all matrix grains and cause rapid grain boundary formation. The Cube texture and Goss texture mutually transform in initial deformation stage and both textures ultimately transform into Copper texture in final deformation stage. The 50% deformation amount is the turning point of mechanical property transformation: (1) When deformation amount is below 50%, tensile strength/yield strength linearly increases and plasticity linearly decreases, which is due to the severe dislocation multiplication and dominant work hardening in this deformation stage. (2) When deformation amount exceeds 50%, the strength-plasticity collaboratively improve, which is mainly because that on one hand, effective grain refinement promotes strong grain boundary strengthening, and on the other hand, increasing grain boundaries promote the coordinated deformation between matrix grains and delay crack initiation and propagation during tensile deformation.

IntroductionUrinary incontinence (UI) significantly impairs women’s quality of life. Identifying its risk factors is essential for developing effective interventions. Sarcopenia, characterized by the accelerated loss of muscle mass and function, is an emerging concern often linked to obesity and abnormal metabolic status, exacerbating various adverse health outcomes. This population-based study aimed to explore the independent and joint associations of sarcopenia, obesity, and metabolic health with UI risk, as well as to evaluate the mediating role of metabolic indicators in these associationsMethodsA total of 3,557 women aged ≥20 years from the National Health and Nutrition Examination Survey were included. Sarcopenia was assessed using the appendicular lean mass index (ALMI), and obesity was defined by body mass index and waist circumference. Metabolic health was evaluated using revised criteria from the National Cholesterol Education Program-Adult Treatment Panel III. UI was identified through responses to the “Kidney Conditions-Urology” questionnaire and classified into stress UI (SUI), urgency UI (UUI), and mixed UI (MUI). Multivariable logistic regression and restricted cubic spline models were used to evaluate the associations and visualize the relationship between ALMI and UI. Mediation models were constructed to assess the mediating role of metabolic indicators.ResultsWe found that sarcopenia was significantly associated with an increased risk of MUI in the general population. Age-specific analysis revealed that sarcopenia is an independent risk factor for SUI in women aged ≥60, and for MUI in women aged 40–59 years. Sarcopenic obesity, particularly under central obesity criteria, further elevated the risk of UI. Notably, women with the metabolically unhealthy obese phenotype with sarcopenia were at the highest risk for both SUI and MUI. Metabolically unhealthy status, glycohemoglobin, vitamin D, and serum albumin levels were partial mediators of these associations.ConclusionOur findings elucidated the complex interactions between sarcopenia, obesity, and metabolic health, underscoring the critical need for integrated therapeutic strategies that address both metabolic health and targeted nutritional interventions, aiming to enhance muscular health and effectively manage and prevent UI.

Electricity theft detection is very important for the economic benefits of power companies and the effectiveness of safe operation of power systems. At present, the traditional power theft detection method can only identify whether the user has power theft, but cannot perform rapid and accurate inspections for various types of power theft users. Aiming at the characteristics of medium-voltage users with large power consumption and regular power consumption, this paper proposed a method for detecting the type of power theft in medium-voltage distribution lines based on robust regression and convolutional neural network. Firstly, considering the existence of abnormal data due to factors such as communication delay interruption, a robust regression algorithm is used to reduce its impact and improve the accuracy of regression analysis. Secondly, the correction coefficient and error term of each user obtained by regression are taken as the characteristics of user stealing electricity, and input into the convolutional neural network model for training to complete the identification of stealing electricity type. Finally, the method is verified by simulation and measured data. The results show that under different disturbance conditions, the proposed method can accurately identify different types of power stealing behaviors, which can better assist on-site investigation, narrow the investigation scope and improve the verification rate.

Internet gaming disorder (IGD) prompts inquiry into how feedback from prior gaming rounds influences subsequent risk-taking behavior and potential neural mechanisms. Forty-two participants, including 15 with IGD and 27 health controls (HCs), underwent a sequential risk-taking task. Hierarchy Bayesian modeling was adopted to measure risky propensity, behavioral consistence, and affection by emotion ratings from last trial. Concurrent electroencephalogram and functional near-infrared spectroscopy (EEG-fNIRS) recordings were performed to demonstrate when, where and how the previous-round feedback affects the decision making to the next round. We discovered that the IGD illustrated heightened risk-taking propensity as compared to the HCs, indicating by the computational modeling (p = 0.028). EEG results also showed significant time window differences in univariate and multivariate pattern analysis between the IGD and HCs after the loss of the game. Further, reduced brain activation in the prefrontal cortex during the task was detected in IGD as compared to that of the control group. The findings underscore the importance of understanding the aberrant decision-making processes in IGD and suggest potential implications for future interventions and treatments aimed at addressing this behavioral addiction.

ABSTRACT Interaction between viruses and bacteria during the development of infectious diseases is a complex question that requires continuous study. In this study, we explored the interactions between pseudorabies virus (PRV) and Pasteurella multocida (PM), which are recognized as the primary and secondary agents of porcine respiratory disease complex (PRDC), respectively. In vivo tests using mouse models demonstrated that intranasal inoculation with PRV at a sublethal dose induced disruption of murine respiratory barrier and promoted the invasion and damages caused by PM through respiratory infection. Inoculation with PRV also disrupted the barrier function of murine and porcine respiratory epithelial cells, and accelerated the adherence and invasion of PM to the cells. In mechanism, PRV infection resulted in decreased expression of tight junction proteins (ZO-1, occludin) and adherens junction proteins (β-catenin, E-cadherin) between neighboring respiratory epithelial cells. Additionally, PRV inoculation at an early stage downregulated multiple biological processes contributing to epithelial adhesion and barrier functions while upregulating signals beneficial for respiratory barrier disruption (e.g., the HIF-1α signaling). Furthermore, PRV infection also stimulated the upregulation of cellular receptors (CAM5, ICAM2, ACAN, and DSCAM) that promote bacterial adherence. The data presented in this study provide insights into the understanding of virus-bacteria interactions in PRDC and may also contribute to understanding the mechanisms of secondary infections caused by different respiratory viruses (e.g., influenza virus and SARS-CoV-2) in both medical and veterinary medicine.IMPORTANCECo-infections caused by viral and bacterial agents are common in both medical and veterinary medicine, but the related mechanisms are not fully understood. This study investigated the interactions between the zoonotic pathogens PRV and PM during the development of respiratory infections in both cell and mouse models, and reported the possible mechanisms which included: (i) the primary infection of PRV may induce the disruption and/or damage of mammal respiratory barrier, thereby contributing to the invasion of PM; (ii) PRV infection at early stage accelerates the transcription and/or expression of several cellular receptors that are beneficial for bacterial adherence. This study may shed a light on understanding the mechanisms on the secondary infection of PM promoted by different respiratory viruses (e.g., influenza virus and SARS-CoV-2) in both medical and veterinary medicine.