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The numerical results demonstrate that double excitation Shilinikov multi-pulse jumping chaotic and small metastable chaotic vibrations coexist in the bistable asymmetric laminated composite square panel. It is found that the external excitation changes the complexity of the chaos, while the parameter excitation changes the type of chaos. It is verified that the bistable asymmetric laminated composite square panel with small damping is easier to produce double excitation Shilinikov multi-pulse jumping chaotic vibrations.In hydrophobic mini- and microchannels, slug flow with moving contact lines is typically generated under various two-phase flow conditions. There is a significant pressure drop in this flow pattern with moving contact lines, which is closely related to the dynamic contact angles. Researchers have investigated dynamic contact angles experimentally for decades, but due to the limitations of visualization techniques, these experiments have typically been conducted in low Weber number regions (We less then 10-3). In this study, we clearly visualized the dynamic contact angles of a liquid slug in high Weber number regions (10-3 less then We less then 1) via synchrotron X-ray imaging with high temporal (∼1000 fps) and spatial (∼2 μm/pixel) resolutions. We precisely measured the pressure drop with moving contact lines in a hydrophobic minichannel (inner diameter = 1.018 mm). On the basis of our experimental data, we verified previous correlations for dynamic contact angles and explored the relationship between pressure drop with moving contact lines and dynamic contact angles.2D systems that host 1D helical states are advantageous from the perspective of scalable topological quantum computation when coupled to a superconductor. Graphene is particularly promising for its high electronic quality, its versatility in van der Waals heterostructures, and its electron- and hole-like degenerate 0th Landau level. Here we study a compact double-layer graphene SQUID (superconducting quantum interference device), where the superconducting loop is reduced to the superconducting contacts connecting two parallel graphene Josephson junctions. Despite the small size of the SQUID, it is fully tunable by the independent gate control of the chemical potentials in both layers. Furthermore, both Josephson junctions show a skewed current-phase relationship, indicating the presence of superconducting modes with high transparency. In the quantum Hall regime, we measure a well-defined conductance plateau of 2e2/h indicative of counter-propagating edge channels in the two layers.The Proteomics Society, India (PSI), hosted the Metabolomics workshop on experimental and data analysis training for untargeted metabolomics in December 2019. The workshop included six tutorial lectures and hands-on data analysis training sessions presented by seven speakers from across the globe. The tutorials and hands-on data analysis sessions focused on workflows for liquid chromatography-mass spectrometry (LC-MS) based on untargeted metabolomics. We review here three main topics from the workshop, which were uniquely identified as bottlenecks for new researchers (a) experimental design, (b) quality controls during sample preparation and instrumental analysis, and (c) data quality evaluation using open source tools. Our objective here is to present common challenges faced by novice researchers and present guidelines to address them. We provide resources and good practices for researchers who are at the initial stage of setting up metabolomics workflows in their laboratories.Atherosclerosis is the major contributor to cardiovascular diseases. It is a spatially and temporally complex inflammatory disease, in which intravascular accumulation of a plethora of lipids is considered to play a crucial role. To date, both the composition and local distribution of the involved lipids have not been thoroughly mapped yet. Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) enables analyzing and visualizing hundreds of lipid molecules within the plaque while preserving each lipid's specific location. In this study, we aim to identify and verify aortic plaque-specific lipids with high-spatial-resolution 2D and 3D MALDI-MSI common to high-fat-diet-fed low-density lipoprotein receptor deficient (ldlr -/- ) mice and chow-fed apolipoprotein E deficient (apoe-/-) mice, the two most widely used animal models for atherosclerosis. A total of 11 lipids were found to be significantly and specifically colocalized to the plaques in both mouse models. These were identified and belong to one sphingomyelin (SM), three lysophosphatidic acids (LPA), four lysophosphatidylcholines (LPC), two lysophosphatidylethanolamines (LPE), and one lysophosphatidylinositol (LPI). While these lysolipids and SM 340;2 were characteristic of the atherosclerotic aorta plaque itself, LPI 180 was mainly localized in the necrotic core of the plaque.The work presented here follows several others in investigating what capabilities, if any, ambient mass spectrometry might have toward the analysis of compounds commonly associated with smokeless propellant powders. This family of instrumental techniques has attracted curiosity from the field of forensic science due to its desirable properties such as rapid collection of information-rich data, combined with minimal requirements for sample mass and preparation. Experiments were conducted with a "Direct Sample Analysis" ion source integrated with a time-of-flight mass spectrometer. The ionization behaviors of nitroglycerin, methyl and ethyl centralite, akardite, diphenylamine, nitrosodiphenylamine, and nitrated diphenylamine derivatives were investigated specifically, with accurate-mass data presented for each. Diphenylamine standards were used to demonstrate the performance of this instrument, which exhibited good response linearity across 1 order of magnitude and sub-nanogram detection limits. [https://www.selleckchem.com/products/mk-0159.html MK0159] Thirty smokeless powder extracts, recovered from ammunition potentially in circulation within Australia, were analyzed to determine whether the technique is appropriate for rapid analysis of smokeless powder particles. Results demonstrated that the technique might be applied to compare individual particles with each other or to a database. Such a capability may be of value in the examination of explosive devices containing smokeless powder, postblast residues therefrom, or muzzle discharge from a close-range shooting. However, when efforts were made to detect residues from the hands of a volunteer shooter, only some returned positive results, and a high background signal from the sample collection stub indicates that detection using this instrument is thus far insufficiently reliable.