Publications by authors named "Chun-Ming Wu"

The rapid emergence of antimicrobial resistant Gram-negative bacteria compromises current antibiotic efficacy, including the last-resort antibiotic polymyxins, emphasizing the urgent need for novel therapeutic strategies. Nanoscale-based antimicrobials exhibit potential as an alternative treatment strategy. In this study, four furoxan-based nitric oxide (NO)-releasing nanoparticles (NPs) were prepared and their antimicrobial efficacy was tested against different Gram-negative bacteria, including: , , , and via minimum inhibitory testing, where NPs exhibited selective activity against lipopolysaccharide (LPS)-deficient strains and LPS-truncated strains tested.

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Two-dimensional (2D) kagome metals offer a unique platform for exploring electron correlation phenomena derived from quantum many-body effects. Here, we report a combined study of electrical magnetotransport and neutron scattering on YbFe_{6}Ge_{6}, where the Fe moments in the 2D kagome layers exhibit an A-type collinear antiferromagnetic order below T_{N}≈500  K. Interactions between the Fe ions in the layers and the localized Yb magnetic ions in between reorient the c-axis-aligned Fe moments to the kagome plane below T_{SR}≈63  K.

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This study reveals the mechanisms behind the ultralow lattice thermal conductivity κ in β-ZnSb single crystals through inelastic neutron scattering (INS). Analyzing phonon behaviors and the interaction between acoustic phonons and rattling modes, the first experimental evidence of avoided crossing in β-ZnSb is provided. The rattler-phonon avoided crossings contribute to the low κ in a β-ZnSb single crystal, enhancing the thermoelectric figure-of-merit (zT).

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Phonon dynamics in organic-inorganic hybrid perovskites (OIHPs) exhibit inherent complexity driven by the intricate interactions between rotatable organic cations and dynamically disordered inorganic octahedra, mediated by hydrogen bonding. This study aims to address this complexity by investigating the thermal transport behavior of MAPbCl as a gateway to the OIHPs family. The results reveal that the ultralow thermal conductivity of MAPbCl arises from a synergistic interplay of exceptionally low phonon velocities, short phonon lifetimes, and phonon mean free paths approaching the Regel-Ioffe limit.

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  • The study explores the crystal and magnetic properties of the van der Waals antiferromagnet α-RuCl using x-ray and neutron diffraction techniques, identifying its crystal structure as monoclinic (C2/m) at room temperature.
  • As the temperature decreases, a phase transition occurs, forming a rhombohedral (R3-) structure with an isotropic honeycomb lattice and three-fold rotational symmetry.
  • Below a critical temperature of around 6-6.6K, a zigzag-type antiferromagnetic order emerges, exhibiting characteristics tied to the Ising model and revealing complex magnetic behaviors influenced by Kitaev spin interactions.
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The extracellular matrix (ECM) is the fundamental acellular element of human tissues, providing their mechanical structure while delivering biomechanical and biochemical signals to cells. Three-dimensional (3D) tissue models commonly use hydrogels to recreate the ECM and support the growth of cells as organoids and spheroids. Collagen-nanocellulose (COL-NC) hydrogels rely on the blending of both polymers to design matrices with tailorable physical properties.

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  • PNIPAM-grafted cellulose nanofibers (CNFs) are being explored as new thermo-responsive hydrogels, with their effectiveness and gel strength associated with how PNIPAM interacts with CNFs.
  • Experiments involving different synthesis methods showed how temperature affects the structure and behavior of these hydrogels, with specific measurements taken using small angle neutron scattering techniques.
  • The study found that grafting PNIPAM onto CNFs alters their temperature response, shifting the lower critical solution temperature and impacting how the hydrogel behaves in response to temperature changes, which is significant for future biomedical applications.
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  • Supercapacitors have significant potential for sustainable energy solutions, driving extensive research to enhance their performance amid growing energy demands due to technological advancements.
  • Key developments focus on improving materials for supercapacitor components, including electrodes, electrolytes, current collectors, and separators, particularly through the use of water-in-salt (WIS) and deep eutectic solvents (DES).
  • The review highlights the role of two-dimensional nanomaterials like graphene and MXenes in supercapacitors, detailing their synthesis, characterization, electrochemical performance, and the associated challenges and opportunities for future devices.
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  • Nanomedicine is gaining traction for improving drug delivery methods, particularly in treating diseases, with a focus on smart supermagnetic nanocomposites made from iron oxide nanoparticles for targeted delivery of doxorubicin (DOX) to tumors.
  • X-ray diffraction (XRD) analysis confirmed that the structure of iron oxide remained unchanged during the coating process, and the developed nanocomposites showed high drug loading efficiency and capacity, especially under acidic conditions, which is beneficial for targeting tumor environments.
  • The in vitro studies indicated that these nanocomposites notably inhibited the survival of liver cancer cells, demonstrating their potential to enhance treatment outcomes compared to traditional methods.
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  • Group A Streptococcus (GAS) uses a unique combination of two proteins, NADase and Streptolysin O (SLO), to enhance its ability to cause disease.
  • Researchers used advanced techniques like X-ray crystallography and small-angle scattering to unveil the structure and function of the NADase/SLO complex, focusing on how these proteins interact at an atomic level.
  • Their findings highlight the significance of a specific salt-bridge interaction between NADase and SLO, which is crucial for GAS's virulence and survival against the host's immune responses, validated through experiments in mice.
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A depleted antimicrobial drug pipeline combined with an increasing prevalence of Gram-negative 'superbugs' has increased interest in nano therapies to treat antibiotic resistance. As cubosomes and polymyxins disrupt the outer membrane of Gram-negative bacteria via different mechanisms, we herein examine the antimicrobial activity of polymyxin-loaded cubosomes and explore an alternative strategy via the polytherapy treatment of pathogens with cubosomes in combination with polymyxin. The polytherapy treatment substantially increases antimicrobial activity compared to polymyxin B-loaded cubosomes or polymyxin and cubosomes alone.

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  • - The study presents evidence of non-conventional pairing in In and Sn nanoparticle assemblies, highlighting spontaneous magnetizations that emerge as the nanoparticles transition into a superconducting state.
  • - Researchers observed that introducing an external magnetic field or magnetic Ni nanoparticles raised the superconducting transition temperature (T) for In and Sn nanoparticles, revealing a complex interaction between magnetism and superconductivity.
  • - A specific critical magnetic field and Ni composition are necessary to suppress superconductivity, suggesting a unique pairing mechanism where spin-parallel pairs form at the surfaces and spin-antiparallel pairs in the core of the nanoparticles.
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  • The study investigates the arrangement of polymer chains in blend films made from polystyrene (PS), deuterated polystyrene (dPS), and poly(methyl methacrylate) (PMMA) under specific conditions.
  • It finds that by adjusting the blend composition and annealing temperature, the films primarily form layers with dPS preferentially located at surfaces and within PS layers at 230 °C.
  • At 270 °C, dPS still prefers to be near the surfaces in thin films, but this surface segregation is not observed in thicker films.
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  • * This study designed a system using cubosomes—tiny particles—to deliver the neurotrophic factor LM22A-4 specifically to damaged RGCs in a mouse model with elevated IOP, testing different concentrations for optimal effectiveness.
  • * Results indicated that the cubosome formulation with 17% LM22A-4 showed superior interaction with cell membranes and effectively targeted the retina and optic nerve, preventing RGC loss and enhancing visual function, suggesting this
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  • The BAM complex in Gram-negative bacteria assembles β-barrel proteins essential for various functions, including nutrient uptake and toxin export, but its assembly mechanism is not fully understood.
  • Researchers reconstituted BAM subunits into a biomimetic membrane and used QCM-D and neutron reflectometry to study their interactions and structural changes.
  • Results indicated that BamE or a BamDE dimer interacts with BamA, causing conformational changes, whereas BamB or BamD alone does not, and unfolded substrate proteins extend the POTRA domains of BamA to assist in membrane folding.
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Treatment of multidrug-resistant (MDR) bacterial infections increasingly relies on last-line antibiotics, such as polymyxins, with the urgent need for discovery of new antimicrobials. Nanotechnology-based antimicrobials have gained significant importance to prevent the catastrophic emergence of MDR over the past decade. In this study, phytantriol-based nanoparticles, named cubosomes, were prepared and examined by minimum inhibitory concentration (MIC) and time-kill assays against Gram-negative bacteria: , , and .

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  • The study focuses on Fe-doped NiO nanoparticles created through a co-precipitation method, which exhibit improved ferromagnetic properties at room temperature.
  • Neutron powder diffraction indicates that the magnetic moment of 3 ions increases with higher Fe concentrations, suggesting enhanced magnetic interactions within the particles.
  • These enhanced interactions lead to additional magnetic energy barriers, contributing to the potential for room temperature magnetic memory and promising applications in spintronic devices and fundamental physics research.
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Magnetic properties of fully oxygenated bare CuO nanoparticles have been investigated using magnetization, X-ray diffraction, neutron diffraction, and Raman scattering measurements. The Langevin field profile is clearly revealed in the isothermal magnetization of 8.8 nm CuO nanoparticle assembly even at 300 K, revealing a 172 times enhancement of the ferromagnetic responses over that of bulk CuO.

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Hypothesis: The water absorption capacity of nanocellulose (NC) foam is tailored by crosslinking with polyethyleneimine (PEI) and hexamethylenediamine (HMDA). The interaction of amine groups in PEI and HMDA with the carboxylic groups (COO) of NC affects the foam structure which reduces its swelling capacity.

Experiments: Functionalised NC foams were prepared by TEMPO (2,2,6,6,-tetramethylpiperidine-1-oxyl) oxidation of bleached pulp, followed by fibrillation into a hydrogel, adding a crosslinker and freeze drying the hydrogel into a foam.

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Ultraviolet irradiation (UVI) of varied duration caused cross-linking and neutralization of polystyrene (PS) homopolymers of molar mass () from 6 to 290 kg mol on a silicon-oxide surface. An optimal neutral skin layer on the surface of the PS was obtained via brief UVI in air (UVIA), by which the PS had no preferential interaction with either block in the copolymer. UVI in an inert environment (gaseous dinitrogen) (UVIN) stabilized the PS layers via cross-linking and enabled the PS networks to have an effective adhesive contact with the underlying substrate.

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is a notorious human bacterial pathogen with considerable capacity to develop antibiotic resistance. We have observed that human infections caused by highly drug-resistant are more prolonged, complicated, and difficult to eradicate. Here we describe a metabolic adaptation strategy used by clinical strains that leads to resistance to the last-line antibiotic, daptomycin, and simultaneously affects host innate immunity.

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We investigated the relationship between the self-assembled morphology of poly( tert-butyl acrylate)- block-poly(6-[4-(4'-methoxyphenylazo)phenoxy]hexyl methacrylate) (P tBA- b-PAzoMA) block copolymers and their photoresponsive and fluorescence behaviors. The morphology of P tBA- b-PAzoMA copolymers was manipulated by dissolving them in mixed dimethylformamide (DMF)/hexanol solvents. When P tBA- b-PAzoMA was dissolved in DMF-rich (neutral) solvents, a favorable interaction between the DMF molecules and both blocks resulted in a random-coiled conformation.

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A large enhancement of the Ni and Cr ferromagnetic moments under UV-light irradiation has been detected in 55 nm thick KNi[Cr(CN)][(HO)]·0.11HO Prussian blue analogues coated on 240 nm RbCo[Fe(CN)][(HO)]·0.56HO nanocubes.

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The interactions between ions and phospholipids are closely associated with the structures and functions of cell membrane. Instead of conventional aqueous systems, we systematically investigated the effects of inorganic ions on the self-assembly of lecithin, a zwitterionic phosphatidylcholine, in cyclohexane. Previous studies have shown that addition of inorganic salts with specific divalent and trivalent cations can transform lecithin organosols into organogels.

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Background: Glioblastoma (GBM) is the most common and most aggressive form of brain cancer. After surgery, radiotherapy is the mainstay of treatment for GBM patients. Unfortunately, the vast majority of GBM patients fail responding to radiotherapy because GBM cells remain highly resistant to radiation.

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