Exosomal miR-494 from Bone Marrow Mesenchymal Stem Cells Attenuates Ferroptosis and Enhances Spinal Cord Injury Repair by Modulating the SIRT1/HO-1 Pathway.

Spinal cord injury (SCI) is a severe traumatic disorder of the central nervous system, often resulting in partial or complete loss of sensory and motor functions. Ferroptosis, a lipid peroxidation-driven apoptotic process triggered by iron overload, has emerged as a novel form of programmed cell death and a focal point in post-SCI cell death research. Exosomes (Exo), as delivery vehicles, exhibit multiple advantages, including superior encapsulation capacity, high targeting efficiency, and enhanced blood-brain barrier penetration to reach the central nervous system.

Loss-free tensile ductility of dual-structure titanium composites via an interdiffusion and self-organization strategy.

The deformation-coordination ability between ductile metal and brittle dispersive ceramic particles is poor, which means that an improvement in strength will inevitably sacrifice ductility in dispersion-strengthened metallic materials. Here, we present an inspired strategy for developing dual-structure-based titanium matrix composites (TMCs) that achieve 12.0% elongation comparable to the matrix Ti6Al4V alloys and enhanced strength compared to homostructure composites.

Parallel Frequency Function-Deep Neural Network for Efficient Approximation of Complex Broadband Signals.

In recent years, with the growing popularity of complex signal approximation via deep neural networks, people have begun to pay close attention to the spectral bias of neural networks-a problem that occurs when a neural network is used to fit broadband signals. An important direction taken to overcome this problem is the use of frequency selection-based fitting techniques, of which the representative work is called the PhaseDNN method, whose core idea is the use of bandpass filters to extract frequency bands with high energy concentration and fit them by different neural networks. Despite the method's high accuracy, we found in a large number of experiments that the method is less efficient for fitting broadband signals with smooth spectrums.

Dual attention enhancement feature fusion network for segmentation and quantitative analysis of paediatric echocardiography.

Paediatric echocardiography is a standard method for screening congenital heart disease (CHD). The segmentation of paediatric echocardiography is essential for subsequent extraction of clinical parameters and interventional planning. However, it remains a challenging task due to (1) the considerable variation of key anatomic structures, (2) the poor lateral resolution affecting accurate boundary definition, (3) the existence of speckle noise and artefacts in echocardiographic images.

Scaling laws of electroconvective flow with finite vortex height near permselective membranes.

In a steady state, the linear scaling laws are confirmed between the intensity characteristics of electroconvective (EC) vortex (including the vortex height and electroosmotic slip velocity) and the applied voltage for the nonshear EC flow with finite vortex height near permselective membranes. This finding in the nonshear EC flow is different from the shear EC flow [Kwak et al., Phys.

Shear electroconvective instability in electrodialysis channel under extreme depletion and its scaling laws.

The electroconvective instability (ECI) in an electrodialysis channel under a strong electric field is studied here. The phenomenon of ECI with extreme depletion (ECI-HD) is reported; that is, the overlapping vortices cause the extreme depletion zone to propagate in the horizontal direction. Using scaling theory and direct numerical simulation, we indicate a series of features under the ECI-HD.

[Study on the epidemic development of COVID-19 in Hubei province by a modified SEIR model].

Objective: To establish a SEIR epidemic dynamics model that can be used to evaluate the COVID-19 epidemic, and to predict and evaluate the COVID-19 epidemic in Hubei province using the proposed model.

Methods: COVID-19 SEIR transmission dynamics model was established, which took transmission ability in latent period and tracking quarantine interventions into consideration. Based on the epidemic data of Hubei province from January 23, 2020 to February 24, 2020, the parameters of the newly established modified SEIR model were fitted.

Stress Concentration and Damage Factor Due to Central Elliptical Hole in Functionally Graded Panels Subjected to Uniform Tensile Traction.

Functionally graded material (FGM) can optimize the mechanical properties of composites by designing the spatial variation of material properties. In this paper, the stress distribution of functionally graded panel with a central elliptical hole under uniaxial tensile load is analyzed. Based on the inhomogeneity variation and three different gradient directions, the effects of the inhomogeneity on the stress concentration factor and damage factor are discussed.

Length-dependent dual-mechanism-controlled failure modes in silver penta-twinned nanowires.

A series of molecular dynamics simulations on silver penta-twinned nanowires are performed to reveal the tensile failure mechanisms that are responsible for the different failure modes and morphologies of fracture surfaces observed in various experimental reports. The simulations show that a ductile-to-brittle transition in failure mode occurs with increasing length of the nanowires. Short nanowires have ductile-like plasticity with flat-like fracture surfaces, while long nanowires show brittle-like fractures with cone-like failure surfaces.

Size-dependent melting modes and behaviors of Ag nanoparticles: a molecular dynamics study.

The size-dependent melting behaviors and mechanisms of Ag nanoparticles (NPs) with diameters of 3.5-16 nm were investigated by molecular dynamics (MD). Two distinct melting modes, non-premelting and premelting with transition ranges of about 7-8 nm, for Ag NPs were demonstrated via the evolution of distribution and transition of atomic physical states during annealing.