Publications by authors named "Li Mei Xu"

Arginine kinase (AK) from the phosphagen kinase family is a cross-reactive shellfish allergen. Structurally related cross-reactive allergens are involved in the pathogenesis of allergic symptoms. This study aimed to unravel the cross-reactivity of AK from a structural perspective.

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Low-dimensional water transport can be drastically enhanced under atomic-scale confinement. However, its microscopic origin is still under debate. In this work, we directly imaged the atomic structure and transport of two-dimensional water islands on graphene and hexagonal boron nitride surfaces using qPlus-based atomic force microscopy.

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Ice surfaces are closely relevant to many physical and chemical properties, such as melting, freezing, friction, gas uptake and atmospheric reaction. Despite extensive experimental and theoretical investigations, the exact atomic structures of ice interfaces remain elusive owing to the vulnerable hydrogen-bonding network and the complicated premelting process. Here we realize atomic-resolution imaging of the basal (0001) surface structure of hexagonal water ice (ice Ih) by using qPlus-based cryogenic atomic force microscopy with a carbon monoxide-functionalized tip.

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The permeability and selectivity of biological and artificial ion channels correlate with the specific hydration structure of single ions. However, fundamental understanding of the effect of ion-ion interaction remains elusive. Here, via non-contact atomic force microscopy measurements, we demonstrate that hydrated alkali metal cations (Na and K) at charged surfaces could come into close contact with each other through partial dehydration and water rearrangement processes, forming one-dimensional chain structures.

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Article Synopsis
  • The study focuses on how ions interact with water at solid surfaces, which is crucial for understanding electrical double layers and ion transport.
  • Direct observations were made using advanced microscopy techniques to analyze alkali metal cations in a water environment on different surfaces (graphite and graphene).
  • The research shows that on hydrophobic surfaces like graphite, ions become disordered, while on hydrophilic surfaces like graphene, they align in a structured way, indicating that surface characteristics heavily influence ion behavior and arrangement.
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The nature of hydrated proton on solid surfaces is of vital importance in electrochemistry, proton channels, and hydrogen fuel cells but remains unclear because of the lack of atomic-scale characterization. We directly visualized Eigen- and Zundel-type hydrated protons within the hydrogen bonding water network on Au(111) and Pt(111) surfaces, using cryogenic qPlus-based atomic force microscopy under ultrahigh vacuum. We found that the Eigen cations self-assembled into monolayer structures with local order, and the Zundel cations formed long-range ordered structures stabilized by nuclear quantum effects.

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The hydrogen-bonding networks of water have strong intra- and intermolecular vibrational coupling which influences the energy dissipation and proton transfer in water. Disentangling and quantitative characterization of different coupling effects in water at a single-molecular level still remains a great challenge. Using tip-enhanced inelastic electron tunneling spectroscopy (IETS) based on low-temperature scanning tunneling microscopy, we report the direct quantitative assessment of the intermolecular coupling constants of the OH-stretch vibrational bands of an isolated water tetramer adsorbed on a Au(111)-supported NaCl(001) bilayer film.

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Background: Continuous positive airway pressure (CPAP) is a major treatment strategy for severe chronic obstructive pulmonary disease (COPD), especially with respiratory failure. However, it remains inconclusive whether CPAP affects respiratory mechanics and neural drive in stable COPD patients without respiratory failure.

Methods: Twenty-two COPD patients without respiratory failure received CPAP starting from 4 to 10 cmHO in 1 cmHO increments.

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Article Synopsis
  • * Using noncontact atomic-force microscopy with a CO-terminated tip, researchers successfully imaged fragile edge structures, revealing both armchair and zigzag types during growth.
  • * Findings suggest that zigzag growth occurs through the addition of water molecules, while armchair growth involves local seeding, challenging traditional beliefs about 2D ice growth mechanisms.
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The objective of this study was to investigate the evolution of antibiotic resistance phenotypes, antibiotic resistance genes (ARGs) and Class 1 integron of Salmonella in municipal wastewater treatment plants (WWTPs). A total of 221 Salmonella strains were isolated from different stages of three WWTPs. After the susceptibility testing, high frequency of resistance was observed for tetracycline (TET, 47.

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Objective: Compared with the 2011 Global Initiative for Chronic Obstructive Lung Disease (GOLD), there have been significant changes in the 2017 GOLD classification. The purpose of this study was to analyze the changes in clinical characteristics of the new A-B-C-D system and to explore its role in comprehensive assessment of COPD.

Subjects And Methods: A total of 631 stable COPD patients were included in a cross-sectional survey.

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In this Letter, the links to Supplementary Videos 5, 7, 9 and 10 were incorrect, and there were some formatting errors in the Supplementary Video legends. These errors have been corrected online.

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To illustrate the species and characteristics of filamentous microorganisms in bulking sludge, culture method, microscopic examination and molecular biological analysis were conducted to isolate and identify the filamentous microorganisms existing in bulking sludge collected from municipal wastewater treatment plant. Filamentous microorganisms isolated by Gause's synthetic agar medium and starch agar fell into 18 genera, among which and belong to bacterial phylum Actinobacteria, all other isolates were classified into fungi. and were the fungi with high occurrence frequency in culture medium.

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Ion hydration and transport at interfaces are relevant to a wide range of applied fields and natural processes. Interfacial effects are particularly profound in confined geometries such as nanometre-sized channels, where the mechanisms of ion transport in bulk solutions may not apply. To correlate atomic structure with the transport properties of hydrated ions, both the interfacial inhomogeneity and the complex competing interactions among ions, water and surfaces require detailed molecular-level characterization.

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We chose () and poliovirus as a typical pathogenic bacterium and virus, respectively. The effects of two typical disinfectants (chlorine and ultraviolet) on each of them were investigated based on microbial culture and quantitative PCR methods. The results showed that Poliovirus was appreciably more resistant to chlorine (required disinfection dose for 1-log microbial reduction:10.

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Article Synopsis
  • Domestic wastewater contains various pathogens, particularly viruses, which can lead to severe waterborne diseases if not adequately treated.
  • * Research focuses on understanding virus behavior in water and improving elimination methods at wastewater treatment plants.
  • * The paper reviews virus detection methods, the effectiveness of treatment processes like coagulation and UV disinfection, and highlights the need for advanced technologies for better viral pathogen control.
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Objective: To investigate the safety and efficacy of transvaginal hydrolaparoscopic pelvic adhesiolysis (THLPA) treatment in the infertile women.

Methods: From May 2007 to Sep. 2008, 30 infertile patients underwent THLPA.

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To explore the basis of metastasis, we compared the human breast cancer lines MCF-7 and MDA-MB453, which have low invasive ability, with their sublines MCF7-I4 and MDA-MB453-I4 with high invasive ability for gene expression and signaling pathways. We previously showed that the I4 lines had dramatically elevated levels of Twist compared with their parental lines. In this study, we observed significantly increased STAT3 Tyr(705) phosphorylation, but not the STAT3 protein levels, in the I4 lines.

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Objective: To investigate the advantages of fertiloscopy in the examination and therapy of infertile women.

Methods: One hundred and fifteen infertile patients underwent fertiloscopy including transvaginal hydrolaparoscopy (THL), conventional dye-test, hysteroscopy, and dye-test using catheterization of the tubal ostium by hysteroscopy from May 2003 to Mar 2005. Access to the pouch of Douglas was achieved in 110 patients (95.

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