Materials (Basel)
November 2024
The fracture position of a friction plug welding (FPW) joint is typically located at or near the thermo-mechanically affected zone (TMAZ). Here, we found that microcracks in all FPW specimens initiate at the deformed plug center (DPC) zone and then propagate through the plug center along 45° shear surfaces, because the lowest hardness occurs at the DPC zone rather than the TMAZ or other zones, and the DPC zone presents a tilt fiber-like microstructure. Such a tilt microstructure stimulates formations and deformations of microvoids and propagation of microcracks along 45° shear surfaces.
View Article and Find Full Text PDFAims: This study aims to reveal transcriptome-wide intronic polyadenylation (IPA) events associated with Pre-eclampsia (PE).
Background: Pre-eclampsia (PE) is a potentially life-threatening complication of pregnancy, affecting both maternal and fetal health. However, our understanding of the underlying molecular mechanisms of PE remains limited.
Background: In recent years, we have observed the pivotal role of immunotherapy in improving survival for patients with non-small cell lung cancer (NSCLC). However, the effectiveness of immunotherapy in the perioperative (neoadjuvant + adjuvant) treatment of resectable NSCLC remains uncertain. We conducted a comprehensive analysis of its antitumor efficacy and adverse effects (AEs) by pooling data from the KEYNOTE-671, NADIM II, and AEGEAN clinical trials.
View Article and Find Full Text PDFRecent millimetre-scale studies proposed that ultrasonic vibrations (UVs) promote material flow in welding joints acting on dislocations. Here, we report atomic-scale results from molecular dynamics simulations of Mg-Al nanolayers joined by two means: only heat and heat accompanied by UVs (vibration amplitude, = 0.1-10 nm and vibration frequency, = 5.
View Article and Find Full Text PDFExtracellular vesicles (EVs) can intercellularly transmit a wide range of bioactive molecules, and these cargoes may potentially serve as therapeutic biomarkers for preeclampsia. Herein, the current study aims to elucidate the mechanism underlying the human trophoblast cell-derived EV-mediated miRNA-mRNA network that could potentially influence the development of preeclampsia based on microarray datasets from publicly available GEO databases. Preeclampsia-related genes were retrieved from the GeneCards and CTD databases, which were then subjected to GO and KEGG enrichment analyses in an effort to identify key pathways in preeclampsia.
View Article and Find Full Text PDFThermal diffusion plays an important role in the determination of the structures and properties of interfaces and nanolayers. Here we report results from molecular dynamics simulations of the tensile behavior of Al-Mg-Al nanolayers with their Al/Mg interfaces being joined by the thermal diffusion of atoms. We find that a different deformation mechanism applies in each case: low thermal diffusion temperatures (300 ≤ 1 < 664 K) and high thermal diffusion temperatures (664 ≤ 1 ≤ 846 K).
View Article and Find Full Text PDFNanotechnology
January 2022
The melting at the magnesium/aluminum (Mg/Al) interface is an essential step during the fabrications of Mg-Al structural materials and biomaterials. We carried out molecular dynamics simulations on the melting at the Mg/Al interface in a Mg-Al-Mg nanolayer via analyzing the changes of average atomic potential energy, Lindemann index, heat capacity, atomic density distribution and radial distribution function with temperature. The melting temperatures (Tm) of the nanolayer and the slabs near the interface are significantly sensitive to the heating rate (vh) over the range ofvh ≤ 4.
View Article and Find Full Text PDFControlling droplet dynamics via wettability or movement at the nanoscale is a significant goal of nanotechnology. By performing molecular dynamics simulations, we study the wettability and spontaneous coalescence of Cu droplets confined in two carbon walls. We first focus on one drop in the two-wall confinement to reveal confinement effects on wettability and detaching behavior of metallic droplets.
View Article and Find Full Text PDFThe solidification of two-dimensional liquid silicon confined to a slit nanopore has been studied using molecular dynamics simulations. The results clearly show that the system undergoes an obvious transition from liquid to multilayer hexagonal film with the decrease of temperature, accompanied by dramatic change in potential energy, atomic volume, coordination number and lateral radial distribution function. During the cooling process, some hexagonal islands randomly appear in the liquid first, then grow up to grain nuclei, and finally connect together to form a complete polycrystalline film.
View Article and Find Full Text PDFThe behavior of water droplets located on graphene in the presence of various external electric fields (E-fields) is investigated using classical molecular dynamics (MD) simulations. We explore the effect of E-field on mass density distribution, water polarization as well as hydrogen bonds (H-bonds) to gain insight into the wetting properties of water droplets on graphene and their interfacial structure under uniform E-fields. The MD simulation results reveal that the equilibrium water droplets present a hemispherical, a conical and an ordered cylindrical shape with the increase of external E-field intensity.
View Article and Find Full Text PDFMolecular dynamics (MD) simulations are carried out to study the coalescence of identical adjacent and nonadjacent water films on graphene (G), vertically or horizontally stacked carbon nanotube arrays (VCNTA and HCNTA respectively). We highlight the key importance of carbon-based substrates in the growth of the liquid bridge connecting the two water films. This simulation provides reliable evidence to confirm a linear increase of the liquid bridge height, which is sensitive to the surface properties and the geometric structure.
View Article and Find Full Text PDFThe structure of quasi-2D liquid silicon confined to slit nanopores has been investigated using molecular dynamics (MD) simulations. An obvious structural change from a low-density low-coordinated liquid to a high-density highly coordinated liquid has been found in the confined silicon with the increase of the slit size. This kind of structural transition results from layering in the confined silicon, which disappears with the increase of temperature.
View Article and Find Full Text PDFIn this work, we report simulation evidence that the graphene surface decorated by carbon nanotube pillars shows strong dewettability, which can give it great advantages in dewetting and detaching metallic nanodroplets on the surfaces. Molecular dynamics (MD) simulations show that the ultrathin liquid film first contracts then detaches from the graphene on a time scale of several nanoseconds, as a result of the inertial effect. The detaching velocity is in the order of 10 m/s for the droplet with radii smaller than 50 nm.
View Article and Find Full Text PDFMolecular dynamics simulations are performed to study the cooling process of quasi-2D liquid carbon. Our results show an obvious liquid-liquid phase transition (LLPT) from the twofold coordinated liquid to the threefold coordinated liquid with the decrease of temperature, followed by a liquid-solid phase transition (LSPT). The LLPT can be regarded as the preparation stage of LSPT.
View Article and Find Full Text PDFObjective: To identify the resources of Gynostemma pentaphyllum and its spurious breed plant Cayratia japonica at level of DNA.
Methods: Two random primers ( WGS001, WGS004) screened were applied to do random amplification with genomic DNA extracted from Gynostemma pentaphyllum and Cayratia japonica which were collected from different habitats. After amplificated with WGS004, one characteristic fragment about 500 bp which was common to all Gynostemma pentaphyllum samples studied but not to Cayratia japonica was cloned and sequenced.
Objective: To analyze the DNA molecular characters of Centella asiatica with RAPD technology.
Methods: With the genomic DNA as templates extracted from various source of Centella asiatica samples, optimized RAPD PCR reaction systems had been used. The random promers had been screened to amplify the specific molecular fragments of Centella asiatica.